JP6926403B2 - Position detection device and position detection method, exposure device and exposure method, and device manufacturing method - Google Patents

Description

The present invention relates to a technical field of a position detection device and a position detection method capable of detecting the position of a mark formed on an object, an exposure device and an exposure method, and a device manufacturing method.

The exposure apparatus that transfers the device pattern to the substrate detects the position of the alignment mark by irradiating the alignment mark formed on the substrate with the measurement light in order to perform the alignment measurement. The alignment measurement is mainly performed to align the device pattern already formed on the substrate with the device pattern to be newly transferred onto the substrate. However, in some cases, the position of the alignment mark may not be properly detected.

U.S. Patent Publication No. 2004/0033426

The first aspect of the position detection device is a position detection device that detects the position of a mark formed on an object by measuring light from a light source, and at least detects diffracted light of the measurement light through the mark. A detector and a controller that calculates error information regarding a position detection error due to the asymmetry of the mark and the height of the mark using the detection result of the detector, and corrects the position information regarding the detection position of the mark. To be equipped with.

A second aspect of the position detection device is a position detection device that detects the position of a mark formed on an object by measuring light from a light source, and at least detects diffracted light of the measurement light through the mark. A controller that uses the detector and the detection result of the detector to calculate the position information regarding the detection position of the mark and the error information regarding the position detection error due to the asymmetry of the mark and the height of the mark. And.

A third aspect of the position detection device is a position detection device that detects the position of a mark formed on an object with measurement light from a light source, and transmits reflected light and diffracted light of the measurement light through the mark. The position of the mark is based on the first information regarding the relationship between the detector to be detected and the intensity of the two types of diffracted light, and the second information regarding the intensity of at least one of the reflected light and the diffracted light. It is provided with a controller that calculates error information regarding the detection error.

A fourth aspect of the position detection device is a position detection device that detects the position of a mark formed on an object by measuring light from a light source, and of the reflected light and diffracted light of the measurement light via the mark. A damping member that attenuates at least a part of the light, a first reflected light component that is attenuated by the dampening member among the reflected light that has passed through the mark, and a first that is attenuated by the dampening member among the diffracted light that has passed through the mark. The diffracted light component, the second reflected light component of the reflected light passing through the mark whose dampening member is not attenuated, and the second reflected light component of the diffracted light passing through the mark where the dampening member is not attenuated. It includes a detector that detects at least one of the diffracted light components.

A fifth aspect of the position detection device is a position detection device that detects the position of a mark formed on an object by measuring light from a light source, and is a reflected light and diffracted light of the measurement light through the mark. A light-shielding member that partially blocks light and a detector that detects at least one of the reflected light and the diffracted light via the light-shielding member are provided, and the light-shielding member has a shape extending along a first direction. One member, a second member having a shape protruding from one end of the first member along a second direction intersecting the first direction, and the second direction from the other end of the first member. Includes a first light-shielding member including a third member having a shape that projects along and toward the projecting side of the second member.

A sixth aspect of the position detection device is a position detection device that detects the position of a mark formed on an object by measuring light from a light source, and of the reflected light and diffracted light of the measurement light through the mark. A light-shielding member that partially blocks light and a detector that detects each of the reflected light and the diffracted light via the light-shielding member are provided, and the light-shielding member includes the reflected light and the diffracted light via the mark. A first light-shielding region capable of light-shielding a part of the light, and a second light that is adjacent to the first light-shielding region along the first direction and can pass a part of the reflected light and the diffracted light through the mark. A first light passing region and a part of the reflected light and a part of the diffracted light that are adjacent to the first shading region along the second direction intersecting the first direction and through the mark can be passed. The two transmission regions, the reflected light and the diffraction via the mark, adjacent to the first light passing region along the second direction, adjacent to the second light passing region along the first direction, and through the mark. A second light-shielding region capable of blocking a part of light is defined.

A seventh aspect of the position detection device is a position detection device that detects the position of a mark formed on an object with measurement light from a light source, and is a first diffraction generated by the measurement light irradiated on the mark. The position of the mark based on at least the detector that detects the light and the second diffracted light, the information on the intensity of the first diffracted light, and the information on the relationship between the first diffracted light and the second diffracted light. It is provided with a controller that calculates error information regarding the detection error of the above mark and corrects the position information regarding the detection position of the mark.

An eighth aspect of the position detection device is a position detection device that detects the position of a mark formed on an object with measurement light from a light source, and is a first diffraction generated by the measurement light irradiated on the mark. Based on at least the detector for detecting the light and the second diffracted light and the information on the intensity of the first diffracted light and the second diffracted light, the position information regarding the detection position of the mark is calculated and the first diffracted light is calculated. A controller for calculating error information regarding a detection error of the position of the mark is provided based on at least information on the intensity of light and information on the relationship between the first diffracted light and the second diffracted light.

The first aspect of the position detection method is to irradiate a mark formed on an object with measurement light, to detect at least the diffracted light of the measurement light through the mark, and to obtain a detection result of the diffracted light. It includes calculating the error information regarding the detection error of the mark position by using the error information, and correcting the position information about the detection position of the mark by using the error information.

The second aspect of the position detection method is to irradiate the mark formed on the object with the measurement light, to detect at least the diffracted light of the measurement light through the mark, and to obtain the detection result of the diffracted light. It includes calculating the error information regarding the detection error of the position of the mark by using it, and calculating the position information about the detection position of the mark by using the detection result of the diffracted light.

The third aspect of the position detection method is to irradiate a mark formed on an object with measurement light, to detect reflected light and diffracted light of the measurement light through the mark, and to detect two types of diffraction. It includes calculating error information regarding a detection error of the position of the mark based on the first information regarding the intensity of light and the second information regarding the intensity of at least one of the reflected light and the diffracted light.

The fourth aspect of the position detection method is to irradiate the mark formed on the object with the measurement light, to attenuate at least a part of the reflected light and the diffracted light of the measurement light through the mark, and the above-mentioned. Of the reflected light passing through the mark, the first reflected light component attenuated by the attenuation, the first diffracted light component of the diffracted light passing through the mark, which is attenuated by the attenuation, and the mark. At least of the second reflected light component of the reflected light that is not attenuated by the attenuation and the second diffracted light component of the diffracted light that has passed through the mark and is not attenuated by the attenuation. Includes detecting one.

A fifth aspect of the position detection method is to irradiate a mark formed on an object with measurement light, from a first member having a shape extending along a first direction, and from one end of the first member. A second member having a shape protruding along a second direction intersecting the first direction, and a second member having a shape protruding from the other end of the first member toward the side along the second direction and protruding from the second member. The light-shielding member including the first light-shielding member including the third member having a protruding shape is moved to block a part of the reflected light and the diffracted light of the measurement light through the mark, and the light-shielding member. Includes detecting each of the reflected light and the diffracted light via.

The sixth aspect of the position detection method is to irradiate the mark formed on the object with the measurement light, and to reflect the reflected light and the diffracted light of the measurement light through the mark in the optical path of the measurement light through the mark. A first light-shielding region capable of blocking light and a part of the diffracted light, and a part of the reflected light and the diffracted light that are adjacent to the first light-shielding region along the first direction and pass through the mark. It passes through the reflected light and a part of the diffracted light which are adjacent to the first light-shielding region and pass through the mark along the second direction intersecting the first light passing region and the first light passing region which can be made to pass. A second light passing region that can be made to be adjacent to the first light passing region along the second direction, adjacent to the second light passing region along the first direction, and via the mark. Setting a second light-shielding region capable of blocking a part of the reflected light and the diffracted light, and detecting the reflected light and the diffracted light of the measured light through the first and second light passing regions. including.

The seventh aspect of the position detection method is to irradiate the mark formed on the object with the measurement light and to detect the first diffracted light and the second diffracted light generated by the measurement light irradiated to the mark. And, based on at least the information on the intensity of the first diffracted light and the information on the relationship between the first diffracted light and the second diffracted light, the error information on the detection error of the position of the mark is calculated. , The error information is used to correct the position information regarding the detection position of the mark.

The eighth aspect of the position detection method is to irradiate the mark formed on the object with the measurement light, and to detect the first diffracted light and the second diffracted light generated by the measurement light irradiated to the mark. The position information regarding the detection position of the mark is calculated based on at least the information regarding the intensity of the first diffracted light and the second diffracted light, the information regarding the intensity of the first diffracted light, and the first. This includes calculating error information regarding the detection error of the position of the mark based on at least the information regarding the relationship between the diffracted light and the second diffracted light.

The first aspect of the exposure apparatus exposes an object using the measurement result of any one of the first to eighth aspects of the position detection apparatus.

In the first aspect of the exposure method, an object is exposed using the measurement result of any one of the first to eighth aspects of the position detection method.

In the first aspect of the device manufacturing method, the object coated with the photosensitizer is exposed, a desired pattern is transferred to the object, and the exposed photosensitizer is transferred to the object by using the first aspect of the exposure method. It is developed to form an exposure pattern layer corresponding to the desired pattern, and the object is processed through the exposure pattern layer.

FIG. 1 is a configuration diagram showing an example of the configuration of the exposure system of the present embodiment. FIG. 2 is a configuration diagram showing an example of the configuration of the exposure apparatus of the present embodiment. FIG. 3 is a configuration diagram showing an example of the configuration of the position detection device of the present embodiment. 4 (a) to 4 (b) are configuration diagrams showing an example of the configuration of the lighting system, respectively. 5 (a) to 5 (b) are side views showing an example of the irradiation mode of the measurement light, respectively. FIG. 6 is a configuration diagram showing an example of the configuration of the light guide optical system. 7 (a) to 7 (d) are plan views showing an example of the configuration of the diaphragm mechanism, respectively. 8 (a), 8 (c) and 8 (e) are plan views showing an example of the alignment mark, respectively, and FIGS. 8 (b), 8 (d) and 8 (f) are shown. , Each is a plan view showing an example of an aperture (transmission region and shading region) defined by a variable field diaphragm. FIG. 9A is a plan view showing the configuration of the image pickup device, and FIG. 9B is a schematic view schematically showing the light intensity distribution shown by the image captured by the image pickup device. 10 (a) and 10 (b) are graphs showing the intensity distribution of the emitted light from the alignment mark, respectively, and FIG. 10 (c) is a graph showing the template function. 11 (a) to 11 (b) are cross-sectional views showing a model in which the asymmetric shape of the alignment mark is simplified, and FIG. 11 (c) shows the relationship between the bottom step and the first asymmetric parameter. 11 (d) is a graph showing the relationship between the mark step and the second asymmetric parameter. FIG. 12 is a graph showing the relationship between the change in the shape of the alignment mark and the first and second asymmetric parameters. FIG. 13 is a graph showing the relationship between the change in the shape of the alignment mark and the first and second asymmetric parameters. Each of FIGS. 14 (a) and 14 (b) is a plan view showing an example of an opening (transmission region and shading region) defined by the variable field diaphragm. FIG. 15A is a configuration diagram showing an example of the configuration of the exposure system, and FIG. 15B is a graph showing the correlation between the superposition accuracy and the asymmetric parameter. FIG. 16 is a flowchart showing the flow of the device manufacturing method.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments described below.
(1) Configuration of Exposure System SYS First, an example of the configuration of the exposure system SYS of the present embodiment will be described with reference to FIG. As shown in FIG. 1, the exposure system SYS includes an exposure device 1, an alignment device 2, a substrate processing device 3, and a storage device 4.

The exposure apparatus 1 exposes an object. In the following, for convenience of explanation, the object is assumed to be a substrate 141 such as a semiconductor substrate coated with a resist. In this case, the exposure apparatus 1 transfers the device pattern (for example, the semiconductor element pattern) to the substrate 141 by exposing the substrate 141. That is, the exposure apparatus 1 is assumed to be an exposure apparatus for manufacturing a device such as a semiconductor element. However, as will be described later, the exposure apparatus 1 may be any exposure apparatus that exposes an arbitrary object or irradiates an arbitrary object with light.

The alignment device 2 performs an alignment measurement on the substrate 141 before the exposure apparatus 1 exposes the substrate 141. Specifically, the alignment device 2 irradiates the alignment mark M formed on the substrate 141 with the illumination light L21. The alignment device 2 images the alignment mark M irradiated with the illumination light L21. The alignment device 2 detects the alignment mark M based on the imaging result. The alignment device 2 measures the position of the alignment mark M based on the detection result of the alignment mark M and the measurement result of the position of the substrate 141. The alignment device 2 performs an EGA (Enhanced Global Alignment) calculation based on the measurement result of the position of the alignment mark M. As a result, the alignment device 2 has the design position coordinates of each of the plurality of shot regions defined on the substrate 141 and the actual positions of each of the plurality of shot regions (that is, the actually measured alignment mark M). It is possible to calculate the alignment parameter indicating the relationship with the actual position of each shot area that can be calculated from the position of. The alignment parameter calculated by the alignment device 2 determines the alignment between the device pattern already formed on the substrate 141 and the device pattern to be newly transferred onto the substrate 141 when the exposure apparatus 1 exposes the substrate 141. Used to do.

The substrate processing apparatus 3 performs a predetermined process on the substrate 141 exposed by the exposure apparatus 1. For example, the substrate processing apparatus 3 may perform development processing on the substrate 141 exposed by the exposure apparatus 1. For example, the substrate processing apparatus 3 may perform a coating treatment of applying a photosensitive agent (in other words, a resist) to the developed substrate 141. In the following description, it is assumed that the substrate processing apparatus 3 is a coater / developer that performs development processing and coating processing on the substrate 141.

The substrate 141 is transported between the exposure device 1, the alignment device 2, and the substrate processing device 3 by a transfer device (not shown). For example, the transfer device takes out the substrate 141 exposed by the exposure apparatus 1 from the exposure apparatus 1, and conveys the taken out substrate 141 to the substrate processing apparatus 3. For example, the transfer device takes out the substrate 141 that has been developed and coated by the substrate processing device 3 from the substrate processing device 3, and conveys the taken out substrate 141 to the alignment device 2. For example, the transfer device takes out the substrate 141 on which the alignment device 2 has performed the alignment measurement from the alignment device 2, and conveys the taken-out substrate 141 to the exposure device 1.

The storage device 4 can store the alignment parameters specified by the alignment device 2. The alignment parameters stored in the storage device 4 can be appropriately read out by the exposure device 1.

The exposure device 1, the alignment device 2, the substrate processing device 3, and the storage device 4 are connected via a network such as a LAN (Local Area Network). Therefore, the exposure device 1, the alignment device 2, the substrate processing device 3, and the storage device 4 can communicate with each other via the network.
(2) Configuration of Exposure Device 1 Subsequently, an example of the configuration of the exposure apparatus 1 will be described with reference to FIG. In the following description, the positional relationship of the components constituting the exposure apparatus 1 will be described using the XYZ Cartesian coordinate system defined from the X-axis, the Y-axis, and the Z-axis which are orthogonal to each other. In the following description, for convenience of explanation, each of the X-axis direction and the Y-axis direction is a horizontal direction (that is, a predetermined direction in the horizontal plane), and the Z-axis direction is a vertical direction (that is, a direction orthogonal to the horizontal plane). Yes, it is assumed that it is substantially in the vertical direction). Further, the rotation directions (in other words, the inclination direction) around the X-axis, the Y-axis, and the Z-axis are referred to as the θX direction, the θY direction, and the θZ direction, respectively.

As shown in FIG. 2, the exposure apparatus 1 includes a mask stage 11, an illumination system 12, a projection optical system 13, a substrate stage 14, an alignment system 15, and a control device 16.

The mask stage 11 can hold the mask 111 on which the device pattern transferred to the substrate 141 is formed. The mask stage 11 can move along a plane (for example, an XY plane) including an illumination region to which the exposure light EL emitted from the illumination system 12 is irradiated while holding the mask 111. For example, the mask stage 11 is moved by the operation of the drive system 112 including the motor. The mask stage 11 can be moved along at least one of the X-axis direction, the Y-axis direction, the Z-axis direction, and the θX direction, the θY direction, and the θZ direction by the operation of the drive system 112. The position of the mask stage 11 is appropriately measured by the position measuring device 113. The position measuring device 113 includes, for example, at least one of a laser interferometer and an encoder system.

The illumination system 12 emits the exposure light EL. The exposure light EL may be, for example, a bright line (for example, g line, h line, i line, etc.) emitted from a mercury lamp. The exposure light EL may be, for example, far-ultraviolet light (DUV light: Deep Ultra Violet light) such as KrF excimer laser light (wavelength 248 nm) or ArF excimer laser light (wavelength 193 nm). The exposure light EL may be, for example, vacuum ultraviolet light (VUV light: Vacum Ultra Violet light) _{such as F 2 laser light (wavelength 157 nm).} The exposure light EL emitted by the illumination system 12 irradiates a part of the mask 111.

The projection optical system 13 projects the exposure light EL (that is, the image of the device pattern formed on the mask 111) transmitted through the mask 111 onto the substrate 141.

The substrate stage 14 holds the substrate 141. The substrate stage 14 can move along a plane (for example, an XY plane) including a projection region on which the exposure light EL is projected by the projection optical system 13 while holding the substrate 141. For example, the substrate stage 14 is moved by the operation of the drive system 142 including the motor. The substrate stage 14 can be moved along at least one of the X-axis direction, the Y-axis direction, the Z-axis direction, and the θX direction, the θY direction, and the θZ direction by the operation of the drive system 142. The position of the substrate stage 14 is appropriately measured by the position measuring device 143. The position measuring device 143 includes, for example, at least one of a laser interferometer and an encoder system.

The alignment system 15 detects the alignment mark M formed in the mark region MA on the substrate 141. Specifically, the alignment system 15 irradiates the alignment mark M with the illumination light L11. The alignment system 15 captures the alignment mark M by receiving the light from the alignment mark M irradiated with the illumination light L11 (that is, at least one of the reflected light and the diffracted light of the illumination light L11). The alignment system 15 detects the alignment mark M based on the imaging result. Therefore, the alignment system 15 is an image processing method FIA (Field Image Alignment). However, the alignment system 15 may be another type of alignment system. The alignment system 15 outputs the detection result of the alignment mark M to the control device 16.

The alignment system 15 is arranged on the side surface of the projection optical system 13. Therefore, the alignment system 15 irradiates the alignment mark M with the illumination light L11 without going through the projection optical system 13. Further, the alignment system 15 captures the alignment mark M by receiving the light from the alignment mark M without going through the projection optical system 13. That is, the alignment system 15 is an off-axis type alignment system. However, the alignment system 15 may irradiate the alignment mark M with the illumination light L11 via the projection optical system 13. The alignment system 15 may image the alignment mark M by receiving the light from the alignment mark M via the projection optical system 13.

The exposure apparatus 1 may include a single alignment system 15. Alternatively, the exposure apparatus 1 may include a plurality of alignment systems 15. In this case, even if one of the plurality of alignment systems 15 is used as the primary alignment system 15 and the other alignment system 15 of the plurality of alignment systems 15 is used as the secondary alignment system 5. good. Further, the plurality of alignment systems 15 may be arranged along a desired direction (for example, the X-axis direction or the Y-axis direction). An exposure apparatus including a plurality of alignment systems 5 is disclosed in, for example, US Pat. No. 8,054,472.

The alignment mark M includes a grid mark formed at a desired pitch Λ. More specifically, the alignment mark M has a grid mark MY formed so as to line up in the first direction (for example, the Y-axis direction) at a desired pitch ΛY, and a third alignment mark M orthogonal to the first direction at a desired pitch ΛX. Includes a grid mark MX formed so as to line up in two directions (eg, the X-axis direction). However, the alignment mark M may be any mark as long as it is a mark that can be detected by the alignment system 15.

On the substrate 141, one or a plurality of mark regions MA corresponding to each shot region on the substrate 141 are arranged. A single grid mark MX may be formed in each mark region MA, or a plurality of grid marks MX may be formed. A single grid mark MY may be formed in each mark region MA, or a plurality of grid mark MY may be formed.

The control device 16 controls the operation of the entire exposure device 1. The control device 16 outputs a control command for operating each operation block included in the exposure apparatus 1 to each operation block. Each operation block operates according to a control command. For example, the control device 16 includes mask position information indicating the position of the mask stage 111 measured by the position measuring device 113, substrate position information indicating the position of the substrate stage 141 measured by the position measuring device 143, and alignment by the alignment system 15. The mark detection information indicating the detection result of the mark M is acquired. The control device 16 specifies the mark position information indicating the position of the alignment mark M based on the mark detection information and the board position information. Further, the control device 16 acquires the alignment parameters calculated by the alignment device 2 from the storage device 4. The control device 6 performs an EGA calculation based on the acquired mark position information and alignment parameters. As a result, the exposure apparatus 1 can calculate an alignment parameter with higher accuracy than the alignment parameter calculated by the alignment apparatus 2. After that, the control device 16 controls the movement of the mask stage 11 and the substrate stage 14 so that the desired device pattern is transferred to the desired position of the desired shot region on the substrate 141 based on the calculated alignment parameters. ..

(3) Configuration of Alignment Device 2 Subsequently, the configuration of the alignment device 2 will be described with reference to FIG. In the following description, the positional relationship of the components constituting the alignment device 2 will be described using the XYZ Cartesian coordinate system defined from the X-axis, the Y-axis, and the Z-axis which are orthogonal to each other. The XYZ Cartesian coordinate system used in the description of the alignment device 2 is different from the XYZ Cartesian coordinate system used in the description of the exposure device 1. However, the point that each of the X-axis direction and the Y-axis direction is the horizontal direction and the Z-axis direction is the vertical direction may be common to both XYZ Cartesian coordinate systems.

As shown in FIG. 3, the alignment device 2 includes an illumination system 21, a light guide optical system 201, a half prism 202, a light guide optical system 203, a half prism 204, an objective optical system 205, and light guide optics. System 206, image pickup element 22, half prism 207, reflection mirror 208, light guide optical system 23, light guide optical system 24, image pickup element 25, image pickup element 26, substrate stage 27, and control device. 29 and is provided.

The illumination system 21 emits illumination light L21 to be applied to the alignment mark M under the control of the control device 29. The illumination light L21 is light that is applied to the alignment mark M in order to image the alignment mark M mainly for the purpose of calculating the alignment parameter. Further, the illumination system 21 emits the measurement light L22 to be applied to the alignment mark M. The measurement light L22 is light that is applied to the alignment mark M in order to image the alignment mark M mainly for the purpose of calculating the asymmetric parameter. The asymmetric parameter is a parameter indicating an error included in the measurement result of the position of the alignment mark M. Such an error occurs, for example, due to a shape distortion including distortion or deviation of the alignment mark M with respect to the ideal or design shape. In particular, such an error is caused by a shape distortion including the shape asymmetry of the alignment mark M (that is, the asymmetry with the optical axis of the objective optical system 205 for guiding the measurement light L22 to the alignment mark M as the axis of symmetry). Occurs.

The illumination system 21 does not emit the measurement light L22 during the period during which the illumination light L21 is emitted. The illumination system 21 does not emit the illumination light L21 during the period during which the measurement light L22 is emitted. The detailed configuration of the lighting system 21 will be described in detail later (see FIG. 4).

The light guide optical system 201 guides the illumination light L21 and the measurement light L22 from the illumination system 21 to the half prism 202. The light guide optical system 201 is arranged on each of the illumination light L21 and the measurement light L22 from the illumination system 21 to the half prism 202. The light guide optical system 201 may include at least one of a refraction optical element and a reflection optical element. The light guide optical system 201 has a numerical aperture NA and an objective optical system 205 of the illumination optical system corresponding to the σ value (that is, the optical system from the illumination system 21 to the measurement light L22 incident on the objective optical system 205). An optical element for adjusting the numerical aperture NA) may be included.

The half prism 202 reflects at least a part of the illumination light L21 and the measurement light L22 from the light guide optical system 201 toward the light guide optical system 203. The half prism 202 is arranged on each optical path of the illumination light L21 and the measurement light L22 from the light guide optical system 201 to the light guide optical system 203.

The light guide optical system 203 guides the illumination light L21 and the measurement light L22 reflected by the half prism 202 to the half prism 204. The light guide optical system 203 is arranged on each of the illumination light L21 and the measurement light L22 from the half prism 202 to the half prism 204. The light guide optical system 203 may include at least one of a refraction optical element and a reflection optical element.

The half prism 204 reflects at least a part of the illumination light L21 and the measurement light L22 from the light guide optical system 203 toward the objective optical system 205. The half prism 204 is arranged on each optical path of the illumination light L21 and the measurement light L22 from the light guide optical system 203 to the light guide optical system 205.

The objective optical system 205 irradiates the substrate 141 with the illumination light L21 and the measurement light L22 reflected by the half prism 204. As a result, when the alignment mark M is located below the objective optical system 205, the objective optical system 205 irradiates the alignment mark M with the illumination light L21 and the measurement light L22, respectively. The objective optical system 205 is arranged on each optical path of the illumination light L21 and the measurement light L22 from the half prism 204 to the substrate 141 (substrate stage 27). The objective optical system 205 may include at least one of a refraction optical element and a reflection optical element.

From the alignment mark M irradiated with the illumination light L21, the emission light L23 generated due to the irradiation of the illumination light L21 is emitted. Specifically, the illumination light L21 applied to the alignment mark M is reflected by the alignment mark M. Therefore, the 0th-order reflected light L23 (0) of the illumination light L21 is emitted from the alignment mark M as at least a part of the emitted light L23. Further, the illumination light L21 applied to the alignment mark M is diffracted by the alignment mark M. Therefore, from the alignment mark M, the +1st-order diffracted light L23 (+1) of the illumination light L21 and the -1st-order diffracted light L23 (-1) of the illumination light L21 are emitted as at least a part of the emitted light L23. However, from the alignment mark M irradiated with the illumination light L21, in addition to or in place of the ± 1st-order diffracted light L23 (± 1), the + K (where K is an integer of 2 or more) next-order diffracted light L23 (where K is an integer of 2 or more) of the illumination light L21. + K) may be emitted. From the alignment mark M irradiated with the illumination light L21, the −Kth-order diffracted light L23 (−K) of the illumination light L21 may be emitted in addition to or in place of the ± 1st-order diffracted light L23 (± 1).

Similarly, the emission light L24 generated due to the irradiation of the measurement light L22 is emitted from the alignment mark M irradiated with the measurement light L22. Specifically, from the alignment mark M, the 0th-order reflected light L24 (0), the + 1st-order diffracted light L24 (+1), and the -1st-order diffracted light L24 (-1) of the measurement light L22 are at least a part of the emitted light L24. Exit. However, the + Kth-order diffracted light L24 (+ K) of the measurement light L22 may be emitted from the alignment mark M irradiated with the measurement light L22 in addition to or in place of the ± 1st-order diffracted light L24 (± 1). From the alignment mark M irradiated with the measurement light L22, the −Kth-order diffracted light L24 (−K) of the measurement light L22 may be emitted in addition to or in place of the ± 1st-order diffracted light L24 (± 1).

The emitted light L23 from the alignment mark M irradiated with the illumination light L21 is incident on the half prism 204 via the objective optical system 205. The half prism 204 transmits at least a part of the light L23 emitted from the objective optical system 205. The emitted light L23 transmitted through the half prism 204 is incident on the light guide optical system 206. Therefore, the half prism 204 is arranged on the optical path of the emitted light L23 from the objective optical system 205 to the light guide optical system 206.

The light guide optical system 206 guides the emitted light L23 reflected by the half prism 204 to the image sensor 22. The light guide optical system 206 is arranged on the optical path of the emitted light L23 from the half prism 204 to the image pickup device 22. The light guide optical system 206 may include at least one of a refraction optical element and a reflection optical element. The light guide optical system 206 may include an optical element for adjusting the numerical aperture of the light guide optical system 206.

The light emitted from the light guide optical system 206 L23 is incident on the image sensor 22. The image sensor 22 includes a CCD sensor or a COMS sensor. The emitted light L23 forms an image on the image pickup surface of the image pickup device 22. Therefore, the image pickup surface of the image pickup device 22 is arranged at a position optically conjugate with the surface of the substrate 141. The first imaging information indicating the imaging result of the imaging element 22 is output to the control device 29. The control device 29 identifies the mark detection information indicating the detection result of the alignment mark M by analyzing the first imaging information. After that, the control device 29 measures the position of the alignment mark M based on the mark detection information and the board position information indicating the position of the board stage 27 measured by the position measuring device 271. Further, the control device 29 performs the EGA calculation based on the measurement result of the position of the alignment mark M. As a result, the control device 29 can calculate the alignment parameter.

Here, an example of the alignment parameter will be described. As described above, the control device 29 calculates the alignment parameter by performing the EGA calculation. In the present embodiment, the EGA calculation is based on the design position coordinates (X, Y) of each of the plurality of shot regions defined on the substrate 141 and the design position coordinates (X, Y). This is a statistical calculation that specifies a model formula that defines the relationship with the correction amount (deviation amount) (dx, dy) of the actual position coordinates of each shot area. The position coordinates (X, Y) and the correction amount (dx, dy) correspond to the substrate coordinate system with the center of the substrate 141 as the origin. In the present embodiment, as a model formula, dx = a ₀ + a ₁ × X + a ₂ × Y + a ₃ × X ² + a ₄ × XY + a ₅ × Y ² + a ₆ × X ³ + a ₇ × X ² Y + a ₈ × XY ² + a ₉ × Model formula Y ³ ... and dy = b ₀ + b ₁ x X + b ₂ x Y + b ₃ x X ² + b ₄ x XY + b ₅ x Y ² + b ₆ x X ³ + b ₇ x X ² Y + b ₈ x XY ² + b ₉ x A model formula called Y ^{3 ... Is used.} The alignment parameters are the coefficients (a ₀ , a ₁ , a ₂ , a ₃ , a ₄ , a ₅ , a ₆ , a ₇ , a ₈ , a ₉ , ..., b ₀ , b _{1 that define the model formula.} , B ₂ , b ₃ , b ₄ , b ₅ , b ₆ , b ₇ , b ₈ , b ₉ ...).

On the other hand, the emitted light L24 from the alignment mark M irradiated with the measurement light L22 is incident on the half prism 204 via the objective optical system 205. The half prism 204 reflects at least a part of the emitted light L24 toward the light guide optical system 203. The light guide optical system 203 guides the emitted light L24 reflected by the half prism 204 to the half prism 202. The half prism 202 transmits at least a part of the light L24 emitted from the light guide optical system 203. The emitted light L24 transmitted through the half prism 202 is incident on the half prism 207. Therefore, the half prism 202 is arranged on the optical path of the emitted light L24 from the light guide optical system 203 to the half prism 207.

The half prism 207 reflects a part of the light L24 emitted from the half prism 202 toward the light guide optical system 23. The half prism 207 further transmits another part of the light L24 emitted from the half prism 202 toward the reflection mirror 208. Therefore, the half prism 207 is arranged on the optical path of the emitted light L24 from the half prism 202 to the light guide optical system 23 and on the optical path of the emitted light L24 extending from the half prism 202 to the reflection mirror 208.

The light guide optical system 23 guides the emitted light L24 reflected by the half prism 207 to the image pickup device 25. The light guide optical system 23 is arranged on the optical path of the emitted light L24 from the half prism 207 to the image pickup device 25. The light guide optical system 23 may include at least one of a refraction optical element and a reflection optical element. In the light guide optical system 23, under the control of the control device 29, the emitted light L24 from the lattice mark MY is incident on the image sensor 25, while the emitted light L24 from the lattice mark MX and the peripheral region of the alignment mark M are emitted from the peripheral region. The emitted light L24 reflected by the half prism 207 is guided to the image sensor 25 so that unnecessary light does not enter the image sensor 25. Therefore, the light guide optical system 23 includes a light-shielding member capable of blocking a part of the emitted light L24 (see, for example, the variable field diaphragm 231, FIGS. 6 and 7 described later). In addition, the light guide optical system 23 guides both the emitted light L24 that has been attenuated to attenuate the intensity by a predetermined amount or more and the emitted light L24 that has not been attenuated to the image sensor 25. .. Therefore, the light guide optical system 23 includes an attenuation member (for example, Kester prism 233, which will be described later, see FIG. 6) for attenuating a part of the emitted light L24 reflected by the half prism 207. The detailed configuration of the light guide optical system 23 will be described in detail later (see FIGS. 6 to 8).

The above-mentioned light-shielding member capable of light-shielding a part of the emitted light L24 is arranged at a position optically conjugate with the surface of the substrate 141. Therefore, the light-shielding member makes it possible to cut out a necessary region from the alignment mark M. Further, the image pickup surface 25a of the image pickup device 25 is conjugate with the pupil of the objective optical system 205, and is also conjugate with the emission end surface of the light guide 217, which will be described later. A diffracted image in which the diffracted light L24 from the alignment mark M is separated is formed at the pupil position of the objective optical system 205. These diffraction images are diffraction images via the alignment mark M of the measurement light L22 from the ejection ports 217a to 217e (see FIG. 4B) formed on the ejection end face of the light guide 217, which will be described later.

The light emitted from the light guide optical system 23 (that is, the light L24 emitted from the grid mark MY) is incident on the image sensor 25. The second imaging information (Y) indicating the imaging result of the imaging element 25 is output to the control device 29. The detailed configuration of the image sensor 25 will be described in detail later (see FIG. 9).

On the other hand, the reflection mirror 208 reflects the emitted light L24 transmitted by the half prism 207 toward the light guide optical system 24. The reflection mirror 208 is arranged on the optical path of the emitted light L24 from the half prism 207 to the light guide optical system 24.

The light guide optical system 24 guides the emitted light L24 reflected by the reflection mirror 208 to the image sensor 26. The light guide optical system 24 is arranged on the optical path of the emitted light L24 from the reflection mirror 208 to the image pickup element 26. The light guide optical system 24 may include at least one of a refraction optical element and a reflection optical element. Under the control of the control device 29, the light guide optical system 24 does not require the emission light L24 from the lattice mark MY and the peripheral region of the alignment mark M while the emission light L24 from the lattice mark MX is incident on the image sensor 26. The emitted light L24 reflected by the reflection mirror 208 is guided to the image sensor 26 so that the light does not enter the image sensor 26. Therefore, the light guide optical system 24 includes a light-shielding member (for example, see the field diaphragm 231, FIGS. 6 and 7 described later) capable of blocking a part of the emitted light L24. In addition, the light guide optical system 24 guides both the emitted light L24 that has been attenuated to attenuate the intensity by a predetermined amount or more and the emitted light L24 that has not been attenuated to the image sensor 26. .. Therefore, the light guide optical system 24 includes an attenuation member (for example, Kester prism 233, which will be described later, see FIG. 6) for attenuating a part of the emitted light L24 reflected by the reflection mirror 208. The configuration of the light guide optical system 24 may be the same as the configuration of the light guide optical system 23.

The above-mentioned light-shielding member capable of light-shielding a part of the emitted light L24 is arranged at a position optically conjugate with the surface of the substrate 141. Therefore, it is possible to cut out a necessary region from the alignment mark M by the light-shielding member. Further, the image pickup surface of the image pickup device 26 is conjugate with the pupil of the objective optical system 205, and is also conjugate with the emission end surface of the light guide 217, which will be described later. A diffracted image in which the diffracted light L24 from the alignment mark M is separated is formed at the pupil position of the objective optical system 205. These diffraction images are diffraction images via the alignment mark M of the measurement light L22 from the ejection ports 217a to 217e (see FIG. 4B) formed on the ejection end face of the light guide 217, which will be described later.

The light emitted from the light guide optical system 24 (that is, the light L24 emitted from the grid mark MX) is incident on the image sensor 26. The second image pickup information (X) indicating the image pickup result of the image pickup element 26 is output to the control device 29. The configuration of the image sensor 26 may be the same as the configuration of the image sensor 25.

A light guide optical system having at least a part of the functions of the light guide optical systems 23 and 24 may be arranged between the half prism 202 and the half prism 207. Further, a bending mirror or the like such as the reflection mirror 208 can be added to an arbitrary place in the optical system according to the actual installation restrictions of the optical system.

The control device 29 calculates the asymmetry parameter regarding the asymmetry of the grid mark MX based on the second imaging information (X). The control device 29 calculates the asymmetry parameter regarding the asymmetry of the grid mark MY based on the second imaging information (Y). In the present embodiment, the control device 29 calculates the first asymmetric parameter and the second asymmetric parameter as the asymmetric parameter. The first asymmetric parameter is the difference between the intensity of the +1st-order diffracted light L24 (+1) and the intensity of the -1st-order diffracted light L24 (-1) (or an arbitrary coefficient that can be calculated from the difference). The second asymmetric parameter is the ratio of the average value of the intensity of the +1st-order diffracted light L24 (+1) and the intensity of the -1st-order diffracted light L24 (-1) to the intensity of the 0th-order reflected light L24 (0) of the emitted light L24. (Or an arbitrary coefficient that can be calculated from the ratio).

Therefore, by analyzing the second imaging information (X), the control device 29 analyzes the 0th-order reflected light L24 (0), the + 1st-order diffracted light L24 (+1), and the -1st-order diffracted light L24 (-) from the lattice mark MX. Calculate the strength of each of 1). After that, the control device 29 calculates the first and second asymmetry parameters regarding the asymmetry of the grid mark MX based on the calculated intensity. Further, the control device 29 analyzes the second imaging information (Y) to obtain the 0th-order reflected light L24 (0), the + 1st-order diffracted light L24 (+1), and the -1st-order diffracted light L24 (-1) from the lattice mark MY. ) Are calculated. After that, the control device 29 calculates the first and second asymmetry parameters regarding the asymmetry of the grid mark MY based on the calculated intensity.

When the shape of the alignment mark M is asymmetrical, the above-mentioned first imaging information (or mark detection information specified from the first imaging information) may include an error due to the asymmetrical shape of the alignment mark M. There is sex. As an example of a state in which the shape of the alignment mark M is asymmetrical, the cross section of the unit structure (for example, a groove, a wall, etc.) constituting the lattice mark MY including the Z axis is the center of the unit structure on the XY plane. There is an asymmetrical state with respect to. As another example of the state in which the shape of the alignment mark M is asymmetric, the cross section including the Z axis of the unit structure constituting the lattice mark MX is asymmetric with respect to the center of the unit structure on the XY plane. Be done.

Therefore, when the shape of the alignment mark M is asymmetrical, the accuracy of the EGA calculation performed based on the mark position information specified from the first imaging information may deteriorate. Specifically, the calculation accuracy of the alignment parameter may deteriorate. Therefore, in the present embodiment, the control device 29 acquires the second imaging information (X) and the second imaging information (Y) in addition to the first imaging information, and the second imaging information (X) and the second imaging information (X). 2 Based on the imaging information (Y), the asymmetric parameter regarding the asymmetric shape of the alignment mark M is acquired. After that, the alignment device 2 can correct the mark position information based on the asymmetry parameter to remove an error component that may remain in the mark position information due to the asymmetry of the shape of the alignment mark M. .. As a result, a relatively highly accurate alignment parameter is calculated as compared with the case where the mark position information is not corrected based on the asymmetric parameter.

The substrate stage 27 holds the substrate 141. The substrate stage 27 can move along a plane (for example, an XY plane) including an irradiation region where the illumination light L21 and the measurement light L22 are each irradiated by the objective optical system 205 while holding the substrate 141. For example, the substrate stage 27 moves by the operation of a drive system (not shown) including a motor. The substrate stage 27 can be moved along at least one of the X-axis direction, the Y-axis direction, the Z-axis direction, and the θX direction, the θY direction, and the θZ direction by the operation of the drive system. The position of the substrate stage 27 is appropriately measured by the position measuring device 271. The position measuring device 271 includes, for example, at least one of a laser interferometer and an encoder system.
(3-2) Configuration of Illumination System 21 Included in Alignment Device 2 Subsequently, the configuration of the illumination system 21 will be described with reference to FIGS. 4 (a) to 4 (b). In this embodiment, an example in which an LD (Laser Video) element is used as a laser light source which is a light source having a high light source brightness and a short wavelength range will be described. A light source having a narrow range, a light source having a narrow wavelength range cut out from a light source having a wide wavelength range such as an Xe lamp, or the like can also be adopted. However, when a laser light source is adopted as the light source, since the coherency of the laser light is high, when the XY measurement is performed at the same time (that is, both the grid mark MX and MY are simultaneously irradiated with the laser light), the XY measurement result (that is, that is) , The second imaging information (X) and the second imaging information (Y)) may be mixed with the interaction component. Therefore, an example using two light sources for X measurement and Y measurement is shown. Further, in this embodiment, an optical system capable of high-speed measurement and high-luminance relay is shown.

As shown in FIG. 4A, the illumination system 21 includes an LD (Laser Diode) element 211a, an LD element 211b, a wideband wavelength switching light source 211c, a light guide fiber 212a, a light guide fiber 212b, and a light guide. Fiber 212c, fiber repeater 213a1, fiber repeater 213a2, fiber repeater 213b, 3-branch light guide fiber 214abd, 2-branch light guide fiber 214ce, double-structured light guide fiber 214f, and optical shutter. 215a, optical shutter 215b, optical shutter 215c, optical shutter 215d, optical shutter 215e, light guide branch 216a, light guide branch 216b, light guide branch 216c, and light guide branch 216d. , A light guide branching portion 216e is provided. The light guide branching portions 216a to 216e and the light guide fiber 214f constitute a light guide 217 that combines these six light guides.

Each of the LD elements 211a and 211b emits a laser beam having a desired wavelength as the measurement light L22. Each of the LD elements 211a and 211b may be capable of emitting a plurality of types of laser light having different wavelengths, or may be capable of emitting a single type of laser light having a single wavelength. When the LD elements 211a and 211b can emit a plurality of types of laser light having different wavelengths, the LD elements 211a and 211b each have a pitch Λ of the alignment mark M under the control of the control device 29. Depending on the situation, the wavelength of the laser beam emitted as the measurement light L22 may be selected. Specifically, the diffraction angle of the ± primary diffracted light L24 (± 1) from the alignment mark M changes according to the wavelength and pitch Λ of the laser beam used as the measurement light L22. Therefore, each of the LD elements 211a and 211b is a laser beam having a wavelength capable of realizing a state in which ± primary diffracted light L24 (± 1) is appropriately incident on each of the image pickup elements 25 and 26 according to the pitch Λ. May be emitted as the measurement light L22. Further, the measurement light L22 has a characteristic that the amount of diffracted light changes depending on a complicated substance structure (for example, a transparent layer, a metal layer, etc.) constituting the alignment mark M. Therefore, the measurement light L22 having a wavelength in which the amount of diffracted light is relatively large (for example, the amount of diffracted light becomes a predetermined amount or more) may be used.

The wideband wavelength switching light source 211c emits light having a desired wavelength as illumination light L21.

Each of the light guide fibers 212a and 212b includes an optical fiber. Each of the light guide fibers 212a and 212b is a single-core type light amount transmission type, and the polarization plane holding type is not necessarily assumed. The light guide fibers 212a and 212b guide the measurement light L22 emitted by the LD elements 211a and 211b to the fiber repeater 213a, respectively. The light guide fiber 212c transmits the amount of light by a bundled light guide including an optical fiber. The light guide fiber 212c guides the illumination light L21 emitted by the broadband wavelength switching light source 211c to the fiber repeater 213b.

The fiber repeaters 213a1 and 213a2 guide the measurement light L22 emitted by the LD elements 211a and 211b to the 3-branch light guide 214abd and the 2-branch light guide 214ce, respectively. Inside each of the fiber repeaters 213a1 and 213a2, a light guide lens that performs at least one of the diffusion processing and the shaping processing of the laser light (that is, the measurement light L22) may be installed. The three-branch light guide 214abd includes write guide branch portions 214a, 214b and 214d. Each of the light guide branch portions 214a, 214b and 214d is a bundle type light guide including an optical fiber. By branching the strand bundle of the three-branched light guide 214abd, the light guide branch portions 214a, 214b and 214d are formed. The minimum number of strands in the bundle of the 3-branch write guide 214abd is 3, but the larger the number of strands, the more the mixing effect of reducing the unevenness of the light source can be expected. Similarly, the two-branch write guide 214ce includes write guide branch portions 214c and 214e. Each of the light guide branch portions 214c and 214e is a bundle type light guide including an optical fiber. The light guide branch portions 214c and 214e are formed by branching the wire bundle of the two-branch light guide 214ce. The minimum number of strands in the bundle of the two-branch light guide 214ce is two, but the larger the number of strands, the more the mixing effect of reducing the unevenness of the light source can be expected.

The light guide branching portion 214a guides the first measurement light L22a out of the five measurement lights L22 obtained by the branching operation to the light shutter 215a. The light guide branch portion 214b guides the second measurement light L22b out of the five measurement lights L22 obtained by the branch operation to the light shutter 215b. The light guide branching portion 214c guides the third measurement light L22c out of the five measurement lights L22 obtained by the branching operation to the light shutter 215c. The light guide branching portion 214d guides the fourth measurement light L22d out of the five measurement lights L22 obtained by the branching operation to the optical shutter 215d. The light guide branching portion 214e guides the fifth measurement light L22e out of the five measurement lights L22 obtained by the branching operation to the optical shutter 215e.

The fiber relay unit 213b guides the incident illumination light L21 to the light guide 217, which is a composite of the six light guides, via the double-structured light guide fiber 214f.

The optical shutter 215a is arranged in the optical path of the first measurement light L22a. The state of the optical shutter 215a can be switched between a state in which the optical shutter 215a blocks the first measurement light L22a and a state in which the optical shutter 215a does not block the first measurement light L22a under the control of the control device 29. .. When the light shutter 215a does not block the first measurement light L22a, the first measurement light L22a is incident on the light guide 217 via the light guide branch portion 216a.

The optical shutter 215b is arranged in the optical path of the second measurement light L22b. The state of the optical shutter 215b can be switched between a state in which the optical shutter 215b blocks the second measurement light L22b and a state in which the optical shutter 215b does not block the second measurement light L22b under the control of the control device 29. .. When the light shutter 215b does not block the second measurement light L22b, the second measurement light L22b is incident on the light guide 217 via the light guide branch portion 216b.

The optical shutter 215c is arranged in the optical path of the third measurement light L22c. The state of the optical shutter 215c can be switched between a state in which the optical shutter 215c blocks the third measurement light L22c and a state in which the optical shutter 215c does not block the third measurement light L22c under the control of the control device 29. .. When the light shutter 215c does not block the third measurement light L22c, the third measurement light L22c is incident on the light guide 217 via the light guide branch portion 216c.

The optical shutter 215d is arranged in the optical path of the fourth measurement light L22d. The state of the optical shutter 215d can be switched between a state in which the optical shutter 215d blocks the fourth measurement light L22d and a state in which the optical shutter 215d does not block the fourth measurement light L22d under the control of the control device 29. .. When the light shutter 215d does not block the fourth measurement light L22d, the fourth measurement light L22d is incident on the light guide 217 via the light guide branch portion 216d.

The optical shutter 215e is arranged in the optical path of the fifth measurement light L22e. The state of the optical shutter 215e can be switched between a state in which the optical shutter 215e blocks the fifth measurement light L22e and a state in which the optical shutter 215e does not block the fifth measurement light L22e under the control of the control device 29. .. When the light shutter 215e does not block the fifth measurement light L22e, the fifth measurement light L22e is incident on the light guide 217 via the light guide branch portion 216e.

Each of the optical shutters 215a to 215e has any configuration as long as it is possible to switch the state between the state in which the corresponding measurement light L22 is shielded and the state in which the corresponding measurement light L22 is not shielded. You may be. Each of the optical shutters 215a to 215e may include a light-shielding plate that can be inserted into and removed from the optical path of the corresponding measurement light L22, and an actuator that drives the light-shielding plate. Each of the optical shutters 215a to 215e may be a liquid crystal shutter.

The light guide 217, which is a combination of the six light guides, emits at least one of the first measurement light L22a to the fifth measurement light L22e as the measurement light L22. As shown in FIG. 4 (b), on the injection end surface of the light guide 217, an injection port 217a for emitting the first measurement light L22a, an injection port 217b for emitting the second measurement light L22b, and a second An injection port 217c for emitting the 3 measurement light L22c, an injection port 217d for emitting the 4th measurement light L22d, and an injection port 217e for emitting the 5th measurement light L22e are formed. The injection port 217a is an end face of another optical fiber optically connected to the light guide branch portion 216a or the light guide branch portion 216a. The injection port 217b is an end face of another optical fiber optically connected to the light guide branch portion 216b or the light guide branch portion 216b. The outlet 217c is an end face of another optical fiber optically connected to the light guide fiber 216c or the light guide branch 216c. The outlet 217d is an end face of another optical fiber optically connected to the light guide branch 216d or the light guide branch 216d. The injection port 217e is an end face of another optical fiber optically connected to the light guide branch portion 216e or the light guide branch portion 216e. The injection port 217a is formed at the center (or near the center) of the injection end face of the light guide 217. The ejection ports 217b to 217e are formed concentrically and at equal angular intervals along the outer edge of the ejection end face of the light guide 217.

The injection port 217a emits the measurement light L22 that can be incident perpendicularly to the surface of the substrate 141. In this case, as shown in FIG. 5A, the 0th-order reflected light L24 (0), the + 1st-order diffracted light L24 (+1), and the -1st-order diffracted light L24 (-1) are emitted from the alignment mark M. Therefore, when the emission port 217a emits the measurement light L22, the alignment device 2 irradiates the alignment mark M with the measurement light L22 once to generate the 0th-order reflected light L24 (0) and the + 1st-order diffracted light. Images of L24 (+1) and -1st order diffracted light L24 (-1) can be imaged. That is, if the alignment device 2 irradiates the grid mark MY with the measurement light L22 once, the 0th-order reflected light L24 (0), the + 1st-order diffracted light L24 (+1), and the -1st-order diffracted light L24 from the grid mark MY. The strength of each of (-1) can be calculated. Similarly, when the alignment device 2 irradiates the grid mark MX with the measurement light L22 once, the 0th-order reflected light L24 (0), the + 1st-order diffracted light L24 (+1), and the -1st-order diffracted light from the grid mark MX. The strength of each of L24 (-1) can be calculated.

On the other hand, each of the injection ports 217b and the injection port 217e emits the measurement light L22 capable of obliquely incident on the surface of the substrate 141. That is, each of the injection port 217b and the injection port 217e emits the measurement light L22 capable of incident on the substrate 141 at an incident angle larger than 0 degrees and less than 90 degrees. In this case, as shown in FIG. 5B, the 0th-order reflected light L24 (0) and one of the + 1st-order diffracted light L24 (+1) and the + 1st-order diffracted light L24 are emitted from the alignment mark M. (However, depending on the pitch Λ of the alignment mark M and the wavelength of the measurement light L22, both the + 1st-order diffracted light L24 (+1) and the + 1st-order diffracted light L24 may be emitted, and further, + K of the measurement light L22 (however, however, K is an integer of 2 or more) The next diffracted light L24 (+ K) and the −Kth diffracted light L24 (−K) of the measurement light L22 may be emitted). Therefore, when each of the ejection ports 217e emits the measurement light L22 from the ejection port 217b, the alignment device 2 irradiates the same alignment mark M with the measurement light L22 at least twice, so that the 0th-order reflected light is reflected. Images of L24 (0), +1st-order diffracted light L24 (+1), and -1st-order diffracted light L24 (-1) can be imaged. That is, as shown on the left side of FIG. 5B, the alignment device 2 irradiates the grid mark MY with the measurement light L22 once through the injection port 217b, so that the alignment device 2 reflects the 0th order from the grid mark MY. The intensities of the light L24 (0) and the + 1st-order diffracted light L24 (+1) are calculated. Further, as shown on the right side of FIG. 5B, the alignment device 2 has the measurement light L22 with respect to the lattice mark MY via the ejection port 217d arranged at an angular interval of 180 degrees from the ejection port 217b. By irradiating once, the intensities of the 0th-order reflected light L24 (0) and the -1st-order diffracted light L24 (-1) from the lattice mark MY are calculated. Similarly, the alignment device 2 irradiates the grid mark MX with the measurement light L22 once through the ejection port 217c, so that the 0th-order reflected light L24 (0) and the + 1st-order diffracted light L24 (1st-order diffracted light L24) from the grid mark MX ( Calculate the strength of each of +1). Further, the alignment device 2 irradiates the lattice mark MX with the measurement light L22 once through the emission port 217e arranged at an angle interval of 180 degrees from the emission port 217c, thereby causing the lattice mark MX to be used. The intensities of the 0th-order reflected light L24 (0) and the -1st-order diffracted light L24 (-1) are calculated.

The injection port 217a emits the measurement light L22 when the pitch Λ of the alignment mark M is relatively large (for example, at least a predetermined pitch). On the other hand, each of the ejection ports 217b to 217e emits the measurement light L22 when the pitch Λ of the alignment mark M is relatively small (for example, equal to or less than a predetermined pitch).

By controlling the optical shutters 215a to 215e, the control device 29 can determine which of the ejection ports 217a to 217e is used as the ejection port for emitting the measurement light L22. When the emission port 217a emits the measurement light L22, the control device 29 does not block the first measurement light L22a from the optical shutter 215a, while the optical shutters 215b to 215e measure the second measurement light L22b to the fifth measurement light L22b, respectively. The optical shutters 215a to 215e are controlled so as to block the light L22e. When the emission port 217b emits the measurement light L22, in the control device 29, the optical shutter 215b does not block the second measurement light L22b, while the optical shutters 215a and 215c to 215e are the first measurement light L22a and the first measurement light L22a, respectively. The optical shutters 215a to 215e are controlled so as to block the fifth measurement light L22e from the measurement light L22c. When the emission port 217c emits the measurement light L22, in the control device 29, the optical shutter 215c does not block the third measurement light L22c, while the optical shutters 215a to 215b and 215d to 215e each emit the first measurement light L22a. The optical shutters 215a to 215e are controlled so as to block the second measurement light L22b and the fourth measurement light L22d to the fifth measurement light L22e. When the emission port 217d emits the measurement light L22, the control device 29 does not block the fourth measurement light L22d from the light shutter 215d, while the optical shutters 215a to 215c and 215e are the first measurement light L22a to the first measurement light L22a, respectively. The optical shutters 215a to 215e are controlled so as to block the 3rd measurement light L22c and the 5th measurement light L22e. When the emission port 217e emits the measurement light L22, the control device 29 does not block the fifth measurement light L22e from the optical shutter 215e, while the optical shutters 215a to 215d measure the first measurement light L22a to the fourth measurement light L22a, respectively. The optical shutters 215a to 215e are controlled so as to block the light L22d.

Further, in this embodiment, since the illumination system 21 includes two LD elements 211a and 211b as the light source, it is possible to measure (detect) the grid mark MX and the grid mark MY at the same time. In this case, when the emission ports 217b and 217d emit the measurement light L22, the control device 29 does not block the second measurement light L22b and the fourth measurement light L22d, respectively, while the optical shutters 215b and 215d do not block the second measurement light L22b and the fourth measurement light L22d. The optical shutters 215a to 215e are controlled so that the 215a, 215c, and 215e block the first measurement light L22a, the third measurement light L22c, and the fifth measurement light L22e, respectively. When the emission ports 217c and 217e emit the measurement light L22, the control device 29 does not block the third measurement light L22c and the fifth measurement light L22e, respectively, while the optical shutters 215c and 215e do not block the light shutters 215a and 215b, respectively. And 215d control the optical shutters 215a to 215e so as to block the first measurement light L22a, the second measurement light L22b, and the fourth measurement light L22d, respectively. Even if the XY measurements are performed at the same time, since different LD elements 211a and 211b are used as the light sources, the laser light irradiated to the alignment mark M does not interfere and the measurement is possible.

The light guide 217 further emits illumination light L21. As shown in FIG. 4B, the emission end face of the light guide 217 includes a first emission region 217f-1 and a second emission region 217f-2 as an emission region for emitting the illumination light L21. The first injection region 217f-1 is a circular region including the center of the injection end face of the light guide 217. The second injection region 217f-2 is an annular region surrounding the first injection region 217f-2. Each of the first injection regions 217f-1 and 217f-2 corresponds to the end face of the bundle fiber obtained by bundling a plurality of optical fibers.

The first emission region 217f-1 emits illumination light L21 when the numerical aperture of the objective optical system 205 is relatively large (for example, a predetermined number or more) to realize imaging by bright-field illumination. The area. The second emission region 217f-2 is an region that emits illumination light L21 when the numerical aperture of the objective optical system 205 is relatively small (for example, a predetermined number or less) to realize image formation by dark field illumination. Is. Therefore, the control device 29 provides an optical switch (not shown), a switching mirror, or the like that switches the output destination of the illumination light L21 from the light guide fiber 214f between the first emission region 217f-1 and the second emission region 217f-2. You may control it. As a result, when the output destination of the illumination light L21 from the light guide fiber 214f is set to the first emission region 217f-1, the first emission region 217f-1 emits the illumination light L21, while the first emission region 217f-1 is emitted. 2 The emission region 217f-2 does not emit the illumination light L21. On the other hand, when the output destination of the illumination light L21 from the light guide fiber 214f is set to the second emission region 217f-2, the second emission region 217f-2 emits the illumination light L21, while the second emission region 217f-2 emits the illumination light L21. 1 The emission region 217f-1 does not emit the illumination light L21. Further, as described above, when the light guide optical system 201 includes an optical element such as a variable σ diaphragm for adjusting the σ value, for example, the first emission region 217f-1 and the first emission region 217f-1 of the output destination of the illumination light L21. It is also possible to realize various lighting conditions including special lighting by using it in combination with switching between the two emission regions 217f-2.
(3-3) Configuration of Light Guide Optical System 23 Included in Alignment Device 2 Subsequently, the configuration of the light guide optical system 23 will be described with reference to FIG. As shown in FIG. 6, the light guide optical system 23 includes a variable field diaphragm 231, a relay lens 232, and a Kester prism 233.

The variable field diaphragm 231 reflects the emitted light reflected by the half prism 207 so that the emitted light L24 from the lattice mark MY is incident on the image sensor 25 while the emitted light L24 from the lattice mark MX is not incident on the image sensor 25. A part of L24 is shielded from light. In order to block a part of the emitted light L24, the variable field diaphragm 231 includes the diaphragm mechanism 2311 shown in FIG. 7A, the diaphragm mechanism 2312 shown in FIG. 7B, and the diaphragm mechanism 2313 shown in FIG. 7C. And the diaphragm mechanism 2314 shown in FIG. 7 (d) is provided. 7 (a) to 7 (d) show the diaphragm mechanisms 2311 to 2314 along the plane orthogonal to the optical path of the emitted light L24, respectively. Further, for convenience of explanation, it is assumed that the horizontal direction of the paper surface and the vertical direction of the paper surface of FIGS. 7 (a) to 7 (d) correspond to the X-axis direction and the Y-axis direction on the substrate 141, respectively.

As shown in FIG. 7A, the diaphragm mechanism 2311 includes a diaphragm blade 2311a and a diaphragm blade 2311b. Each of the diaphragm blades 2311a and 2311b has a shape extending along the X-axis direction (that is, the X-axis direction is the longitudinal direction). The diaphragm blades 2311a and 2311b are arranged at desired intervals along the Y-axis direction. The diaphragm blades 2311a and 2311b define an opening through which the emitted light L24 can pass in the gap between the diaphragm blades 2311a and the diaphragm blades 2311b (see the dotted line region in FIG. 7A). Each of the diaphragm blades 2311a and 2311b can be moved along the Y-axis direction (or any direction intersecting the X-axis) by the operation of an actuator (not shown) controlled by the control device 29. Therefore, the aperture mechanism 2311 can adjust the size of the opening along the Y-axis direction.

As shown in FIG. 7B, the diaphragm mechanism 2312 includes a diaphragm blade 2312a and a diaphragm blade 2312b. Each of the diaphragm blades 2312a and 2312b has a shape extending along the Y-axis direction (that is, the Y-axis direction is the longitudinal direction). The diaphragm blades 2312a and 2312b are arranged at desired intervals along the X-axis direction. The diaphragm blades 2312a and 2312b define an opening through which the emitted light L24 can pass in the gap between the diaphragm blades 2312a and the diaphragm blades 2312b (see the dotted line region in FIG. 7B). Each of the diaphragm blades 2312a and 2312b can be moved along the X-axis direction (or any direction intersecting the Y-axis) by the operation of an actuator (not shown) controlled by the control device 29. Therefore, the aperture mechanism 2312 can adjust the size of the opening along the X-axis direction.

As shown in FIG. 7C, the diaphragm mechanism 2313 includes a diaphragm blade 2313a and a diaphragm blade 2313b. Each of the diaphragm blades 2313a and 2313b has a shape extending along the X-axis direction (that is, the X-axis direction is the longitudinal direction). In the diaphragm blades 2313a and 2313b, at least a part of the diaphragm blades 2313a overlaps with at least a part of the diaphragm blades 2313b along the optical path of the emitted light L24 (that is, along the direction perpendicular to the paper surface of FIG. 7C). It is arranged like this. The diaphragm blades 2313a and 2313b have openings (dotted lines in FIG. 7 (c)) through which the emitted light L24 can pass on both sides of the diaphragm blades 2313a and 2313b (that is, the + Y side and the −Y side of the diaphragm blades 2313a and 2313b). Area) is specified. Each of the diaphragm blades 2313a and 2313b can be moved along the Y-axis direction (or any direction intersecting the X-axis) by the operation of an actuator (not shown) controlled by the control device 29. Each of the diaphragm blades 2313a and 2313b can be moved along the Y-axis direction by the operation of an actuator (not shown) controlled by the control device 29. Therefore, the diaphragm mechanism 2313 can adjust the distance between the two openings arranged along the Y-axis direction.

As shown in FIG. 7D, the diaphragm mechanism 2314 includes a diaphragm blade 2314a and a diaphragm blade 2314b. The diaphragm blade 2314a includes a first blade portion 2314a-1, a second blade portion 2314a-2, and a third blade portion 2314a-3. The first blade portion 2314a-1 has a shape extending along the Y-axis direction. The second blade portion 2314a-2 has a shape protruding from one end of the first blade portion 2314a-1 along the Y-axis direction along the X-axis direction and toward the throttle blade 2314b. The third blade portion 2314a-3 has a shape protruding from the other end of the first blade portion 2314a-1 along the Y-axis direction along the X-axis direction and toward the drawing blade 2314b. The diaphragm blade 2314b includes a first blade portion 2314b-1, a second blade portion 2314b-2, and a third blade portion 2314b-3. The first blade portion 2314b-1 has a shape extending along the Y-axis direction. The second blade portion 2314b-2 has a shape protruding from one end of the first blade portion 2314b-1 along the Y-axis direction along the X-axis direction and toward the drawing blade 2314a. The third blade portion 2314b-3 has a shape protruding from the other end of the first blade portion 2314b-1 along the Y-axis direction along the X-axis direction and toward the drawing blade 2314a. That is, each of the diaphragm blades 2314a and 2314b has a U-shape. The diaphragm blades 2314a and 2314b define an opening through which the emitted light L24 can pass (see the dotted area in FIG. 7D) at a position surrounded by the diaphragm blades 2314a and the diaphragm blades 2314b. Specifically, the diaphragm blades 2314a and 2314b are surrounded by the first blade portion 2314a-1, the second blade portion 2314a-2, the third blade portion 2314a-3, and the third blade portion 2314b-3. Define an opening in the gap. Further, the diaphragm blades 2314a and 2314b are formed in a gap surrounded by the first blade portion 2314b-1, the second blade portion 2314b-2, the third blade portion 2314b-3, and the third blade portion 2314a-3. Define the opening. Therefore, the aperture mechanism 2314 has a first light-shielding region (for example, a region corresponding to the third blade portion 2314a-3 in FIG. 7D) capable of blocking the emitted light L24, and a first light-shielding region along the Y-axis direction. Adjacent to the first light passing region (for example, the region corresponding to the upper left opening in FIG. 7 (d)) adjacent to the light blocking region and through which the emitted light 24 can pass, and adjacent to the first light blocking region along the X-axis direction. The second light passing region through which the emitted light L24 can pass (for example, the region corresponding to the lower right opening in FIG. 7D) and the first light passing region along the X-axis direction are adjacent to each other. A second light-shielding region (for example, a region corresponding to the third blade portion 2314b-3 in FIG. 7D) that is adjacent to the second light passing region along the Y-axis direction and can block the emitted light L24 is defined. do. That is, the diaphragm mechanism 2314 defines two openings arranged along the directions intersecting both the X-axis direction and the Y-axis direction. Each of the diaphragm blades 2314a and 2314b can be moved along the Y-axis direction by an actuator (not shown) controlled by the control device 29. Therefore, the diaphragm mechanism 2314 can adjust at least one of the distance and size of the two openings arranged along the intersecting directions in the X-axis direction and the Y-axis direction.

The variable field diaphragm 231 uses at least one of such diaphragm mechanisms 2311 to 2314 to pass the emission light L24 from the grid mark MY to the arbitrary alignment mark M and from the grid mark MX. A field diaphragm that blocks the emitted light L24 is defined. For example, with respect to the alignment mark M (see FIG. 8A) in which the grid mark MX is arranged in the first quadrant and the third quadrant and the grid mark MY is arranged in the second and fourth quadrants, FIG. As shown in 8 (b), the variable field aperture 231 uses the aperture mechanisms 2311 and 2314 to pass the emission light L24 from the quadrant mark MY and block the emission light L24 from the lattice mark MX. It can be specified. For example, with respect to the alignment mark M (see FIG. 8C) in which the grid mark MY is arranged in the first quadrant and the third quadrant and the grid mark MX is arranged in the second quadrant and the fourth quadrant, FIG. As shown in 8 (d), the variable field aperture 231 uses the aperture mechanisms 2311 and 2314 to pass the emission light L24 from the quadrant mark MY and block the emission light L24 from the lattice mark MX. It can be specified. The variable field diaphragm 231 shown in FIG. 8 (b) is switched to the variable field diaphragm 231 shown in FIG. 8 (d) when the diaphragm blades 2314a and 2314b move along the Y-axis direction. For example, grid mark MX, grid mark MY, and grid mark, respectively, in three regions each extending along the first direction (for example, the Y-axis direction) and lining up along the second direction (for example, the X-axis direction). For the alignment mark M on which the MX is formed (see FIG. 8 (e)), as shown in FIG. 8 (f), the variable field aperture 231 uses the aperture mechanisms 2311 and 2312 to form the grid mark MY. It is possible to define an opening that allows the light emitted from the L24 to pass through and blocks the light L24 emitted from the grid mark MX. For example, grid mark MY, grid mark MX, and grid mark, respectively, in three regions extending along the first direction (for example, the Y-axis direction) and lining up along the second direction (for example, the X-axis direction), respectively. For the alignment mark M on which the MY is formed (see FIG. 8 (g)), as shown in FIG. 8 (h), the variable field aperture 231 uses the aperture mechanisms 2311 to 2313 to form the grid mark MY. It is possible to define an opening that allows the light emitted from the L24 to pass through and blocks the light L24 emitted from the grid mark MX.

Again, in FIG. 6, the emitted light L24 that has passed through the variable field diaphragm 231 (that is, the emitted light L24 from the grid mark MY) is incident on the first optical surface 233a of the Kester prism 233 via the relay lens 232. The emitted light L24 incident on the first optical surface 233a passes through the first optical surface 233a and is incident on the second optical surface 233b of the Kester prism 233.

A part of the emitted light L24 incident on the second optical surface 233b is reflected by the second optical surface 233b. The emitted light L24 reflected by the second optical surface 233b is incident on the reflection region 233a-1 formed on the first optical surface 233a. The emitted light L24 incident on the reflection region 233a-1 is reflected by the reflection region 233a-1. The emitted light L24 reflected by the reflection region 233a-1 is incident on the third optical surface 233c of the Kester prism 233. The emitted light L24 incident on the third optical surface 233c passes through the third optical surface 233c and is incident on the image sensor 25.

On the other hand, the other part of the emitted light L24 incident on the second optical surface 233b passes through the second optical surface 233b. That is, the second optical surface 233b branches the optical path of the emitted light L24 incident on the Kester prism 233 into a plurality of optical paths. The emitted light L24 transmitted through the second optical surface 233b is incident on the reflection region 233d-1 formed on the fourth optical surface 233d of the Kester prism 233. The emitted light L24 incident on the reflection region 233d-1 is reflected by the reflection region 233d-1. However, the reflectance of the reflection region 233d-1 is smaller than the reflectance of the reflection region 233a-1. For example, the reflectance of the reflection region 233d-1 is 1 / P (where P> 1 and, for example, P = 10) of the reflectance of the reflection region 233a-1. Therefore, it can be said that the reflection region 233d-1 substantially attenuates the emitted light L24 by a predetermined amount or more by reflecting the emitted light L24. The emitted light L24 reflected by the reflection region 233d-1 passes through the third optical surface 233d and is incident on the image sensor 25. Therefore, both the emitted light L24 attenuated by the reflection region 233d-1 and the emitted light L24 not attenuated by the reflection region 233d-1 are incident on the image sensor 25.

Since the configuration of the light guide optical system 24 is the same as the configuration of the light guide optical system 23 as described above, the description of the light guide optical system 23 described above corresponds to the light guide optical system 23 in the description. By substituting the wording with the wording corresponding to the light guide optical system 24, it substantially corresponds to the explanation of the configuration of the light guide optical system 24.
(3-4) Configuration of Image Sensor 25 Included in Alignment Device 2 Subsequently, the configuration of the image sensor 25 will be described with reference to FIGS. 9 (a) and 9 (b). As shown in FIG. 9A, the image pickup surface 25a of the image pickup device 25 includes a first image pickup area 25a-1 and a second image pickup area 25a-2. The first imaging region 25a-1 is a region where the emitted light L24, which is not attenuated by the reflection region 233d-1, is incident. On the other hand, the second imaging region 25a-2 is a region where the emitted light L24 attenuated by the reflection region 233d-1 is incident.

Therefore, as shown in FIG. 9B, the image sensor 25 uses the first image pickup region 25a-1 and has the 0th-order reflected light L24 (0) and ± 1 which are not attenuated by the reflection region 233d-1. The image obtained by forming an image of the next diffracted light L24 (± 1) can be imaged. Further, the image sensor 25 uses the second image pickup region 25a-2 to form an image of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1) attenuated by the reflection region 233d-1. It is possible to image the image obtained in. The image obtained by forming the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1) is the image of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1). The image corresponds to the intensity distribution. FIG. 9B schematically shows the intensity distribution of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1).

Since the image pickup surface 25a includes the first image pickup area 25a-1 and the second image pickup area 25a-2, the intensity of the 0th-order reflected light L24 (0) not attenuated by the reflection area 233d-1 is high. Even when the peak value does not fall within the dynamic range of the image sensor 25a, the alignment device 2 can calculate the intensity of the 0th-order reflected light L24 (0).

Since the configuration of the image sensor 26 is the same as the configuration of the image sensor 25 as described above, the description of the image sensor 25 described above corresponds to the wording corresponding to the image sensor 25 in the description. By substituting the wording, it substantially corresponds to the explanation of the configuration of the image sensor 26.
(4) Flow of Alignment Measurement by Exposure Device 1 and Alignment Device 2 Next, a flow of alignment measurement by the exposure device 1 and alignment device 2 will be described. As described above, the alignment device 2 performs alignment measurement on the substrate 141 before the exposure apparatus 1 exposes the substrate 141. After that, the exposure apparatus 1 performs the alignment measurement with respect to the substrate 141 by using the alignment parameters obtained by the alignment measurement performed by the alignment apparatus 2. Therefore, in the following, after explaining the flow of the alignment measurement performed by the alignment device 2, the flow of the alignment measurement performed by the exposure device 1 will be described.

When the alignment device 2 performs the alignment measurement, the control device 29 controls the illumination system 21 and the substrate stage 27 so as to irradiate the alignment mark M on the substrate 141 with the illumination light L21. In the present embodiment, the alignment device 2 acquires mark position information indicating the positions of one or a plurality of alignment marks M corresponding to each shot region for all of the plurality of shot regions on the substrate 141. Therefore, the control device 29 controls the illumination system 21 and the substrate stage 27 so as to irradiate the illumination light L21 to one or a plurality of alignment marks M corresponding to each of the plurality of shot regions. However, the alignment device 2 targets a part of the plurality of shot regions on the substrate 141 (for example, targets a plurality of sample shot regions), and positions one or a plurality of alignment marks M corresponding to each shot region. The mark position information shown may be acquired.

When the illumination light L21 is irradiated, the image sensor 22 images the alignment mark M irradiated with the illumination light L21. As a result, the control device 29 acquires the first imaging information. After that, the control device 29 acquires the mark detection information by analyzing the first imaging information. In parallel with the acquisition of the mark detection information, the control device 29 acquires the substrate position information indicating the position of the substrate stage 27 (that is, the position of the substrate 141) from the position measuring device 271. After that, the control device 29 specifies the mark position information indicating the position of the alignment mark M irradiated with the illumination light L21 based on the mark detection information and the substrate position information.

When another alignment mark M corresponding to the same shot area exists, the alignment device 2 performs the above-described operation on the other alignment mark M to indicate the position of the other alignment mark M. Identify location information.

After that, the control device 29 switches the light emitted by the illumination system 21 from the illumination light L21 to the measurement light L22. As a result, the measurement light L22 is irradiated to the alignment mark M that has been irradiated with the illumination light L21 instead of the illumination light L21. When the pitch Λ of the alignment mark M corresponding to each shot region is relatively large, the control device 29 emits the measurement light L22 (that is, the measurement L22 perpendicularly incident on the substrate 141) through the injection port 217a. The lighting system 21 is controlled so as to do so. On the other hand, when the pitch Λ of the alignment mark M corresponding to each shot region is relatively small, the control device 29 measures the measurement light L22 (that is, obliquely incident on the substrate 141) via the injection port 217b to 217e. The lighting system 21 is controlled so as to emit L22). In this case, the control device 29 uses the measurement light L22 via the emission port 217b (that is, the measurement light L22 that irradiates the grid mark MY from the first direction) and the measurement light L22 via the emission port 217d (that is, the first measurement light L22). The measurement light L22 that irradiates the lattice mark MY from the second direction opposite to the direction of 1 is emitted, and then the measurement light L22 (that is, the lattice mark MX is emitted from the third direction) through the injection port 217c. The measurement light L22) radiated to the grid mark MX and the measurement light L22 (that is, the measurement light L22 radiated to the grid mark MX from the fourth direction opposite to the third direction) are emitted through the ejection port 217e. In addition, the lighting system 21 is controlled. However, the alignment system 2 may speed up the alignment measurement by duplicating the measurement of the grid marks MX and MY. In this case, the control device 29 uses the measurement light L22 via the emission port 217b (that is, the measurement light L22 that irradiates the grid mark MY from the first direction) and the measurement light L22 via the emission port 217c (that is, the first measurement light L22). The measurement light L22 irradiating the grid mark MX from the third direction is simultaneously emitted, and then the measurement light L22 (that is, the grid mark from the second direction opposite to the first direction) is emitted through the injection port 217d. The measurement light L22) emitted to the MY and the measurement light L22 (that is, the measurement light L22 irradiated to the grid mark MX from the fourth direction opposite to the third direction) are simultaneously emitted through the emission port 217e. The lighting system 21 is controlled so as to do so.

In addition, in the control device 29, based on the pattern of the alignment mark M irradiated with the measurement light L22, the emission light L24 from the lattice mark MY is incident on the image sensor 25, while the emission light L24 from the lattice mark MX is emitted. The variable field diaphragm 231 included in the light guide optical system 23 is controlled so as not to enter the image sensor 25. Further, in the control device 29, based on the pattern of the alignment mark M irradiated with the measurement light L22, the emission light L24 from the lattice mark MX is incident on the image sensor 26, while the emission light L24 from the lattice mark MY is imaged. The variable field diaphragm 231 included in the light guide optical system 24 is controlled so as not to enter the element 26.

As a result, the light emitted from the lattice mark MY irradiated with the measurement light L22 is incident on the image sensor 25. Therefore, the control device 29 acquires the second image pickup information (Y) from the image pickup element 25. Similarly, the light emitted from the lattice mark MY irradiated with the measurement light L22 is incident on the image sensor 26. Therefore, the control device 29 acquires the second image pickup information (X) from the image pickup element 26.

The control device 29 calculates the light intensity distribution on the image pickup surface 25a of the image pickup device 25 (that is, the intensity distribution of the light incident on the image pickup surface 25a) based on the second image pickup information (Y). As a result, as shown in FIG. 10A, the control device 29 acquires a light intensity distribution that shows the intensity distribution of the emitted light L24 from the grid mark MY in a so-called three-dimensional manner. Further, the control device 29 calculates the light intensity distribution on the image pickup surface of the image pickup device 26 (that is, the intensity distribution of the light incident on the image pickup surface) based on the second image pickup information (X). As a result, as shown in FIG. 10B, the control device 29 acquires a light intensity distribution that shows the intensity distribution of the emitted light L24 from the grid mark MX in a so-called three-dimensional manner. In addition, each of FIG. 10A and FIG. 10B is an example of a light intensity distribution including an intensity distribution corresponding to each of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1). Shown. Actually, since the imaging surface 25a includes the first imaging region 25a-1 and the second imaging region 25a-2, the control device 29 receives the 0th-order reflected light L24 (0) in which the reflection region 233d-1 is attenuated. ) And ± 1st-order diffracted light L24 (± 1), respectively, and 0th-order reflected light L24 (0) and ± 1st-order diffracted light L24 (± 1) in which the reflection region 233d-1 is not attenuated, respectively. The light intensity distribution including both the intensity distribution corresponding to is acquired.

Here, the acquired light intensity distribution includes not only the intensity distribution corresponding to the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1), but also the intensity distribution corresponding to the noise light. there is a possibility. Therefore, the control device 29 has a fitting process (in other words, a degree of freedom in the overall intensity) in order to extract the intensity distribution corresponding to each of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1). Perform a certain template matching process)). Specifically, the control device 29 performs a fitting process on the acquired light intensity distribution using a template function indicating an ideal or design intensity distribution of the 0th-order reflected light L24 (0). As a result, the control device 29 can extract the intensity distribution corresponding to the 0th-order reflected light L24 (0) from the light intensity distribution. Therefore, the control device 29 can calculate the intensity of the 0th-order reflected light L24 (0) based on the intensity distribution corresponding to the extracted 0th-order reflected light L24 (0). The same applies to the calculation of the intensity of ± 1st-order diffracted light L + 24 (± 1).

The intensities of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1) change because the structure of the alignment mark M changes depending on the semiconductor process. Therefore, by fitting by changing the size using the template function whose shape is almost fixed, the control device 29 has an intensity distribution of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1). Using the whole, it is possible to extract the corresponding intensities for each. This process is not limited to this method, and various methods such as weighted averaging can be applied because the imaging position of the diffracted light can be predicted in advance from the pitch Λ of the alignment mark M and the like.

When another alignment mark M corresponding to the same shot region exists, the alignment device 2 performs the above-described operation on the other alignment mark M to perform 0th-order reflection from the other alignment mark M. The intensities of the light L24 (0) and the ± primary diffracted light L24 (± 1) are calculated.

The alignment device 2 performs the mark position information acquisition operation and the intensity calculation operation of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1) described above for all shot regions. Repeat. As a result, the control device 29 receives the mark position information, the 0th-order reflected light L24 (0) from the grid mark MY, and the ± 1st-order diffracted light L24 (± 1) for each of the plurality of shot regions on the substrate 141. The intensity and the intensity of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1) from the grid mark MX can be obtained.

After that, the control device 29 calculates the asymmetry parameter regarding the asymmetry of the grid mark MY based on the respective intensities of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1) from the grid mark MY. .. The control device 29 calculates the asymmetry parameter regarding the asymmetry of the grid mark MX based on the intensities of the 0th-order reflected light L24 (0) and the ± 1st-order diffracted light L24 (± 1) from the grid mark MX.

The control device 29 calculates the first asymmetric parameter using Equation 1. In Equation 1, the first asymmetric parameter is P1, the intensity of the ₊ 1st-order diffracted light L24 (+1) in which the reflection region 233d-1 is not attenuated is I 1+, and the reflection region 233d-1 is not attenuated -1. Let the intensity of the next diffracted light L24 (-1) be I _1- . However, the intensity of the +1st-order diffracted light L24 (+1) _{in which the reflection region 233d-1 is attenuated may be I 1+,} and the intensity of the -1st-order diffracted light L24 (-1) in which the reflection region 233d-1 is attenuated may be _{I 1-.} ..

数式１に示す第１非対称パラメータは、アライメントマークＭ毎に算出される。ここで、計測光Ｌ２２の強度のばらつきが発生する場合には、一のアライメントマークＭに照射された計測光Ｌ２２の強度と他のアライメントマークＭに照射された計測光Ｌ２２の強度とが一致しない可能性がある。このため、第１非対称パラメータが単に＋１次回折光Ｌ２４（＋１）の強度Ｉ_１＋と−１次回折光Ｌ２４（−１）の強度Ｉ_１＋との差分である場合には、第１非対称パラメータは、アライメントマークＭの非対称性に起因することなく、計測光Ｌ２２の強度のばらつきに起因して変動してしまう可能性がある。つまり、一のアライメントマークＭに対応する第１非対称パラメータと他のアライメントマークＭに対応する第１非対称パラメータとが、計測光Ｌ２２の強度のばらつきに起因して、適切に比較可能なパラメータにならない可能性がある。しかるに、本実施形態では、第１非対称パラメータは、＋１次回折光Ｌ２４（＋１）の強度Ｉ_１＋と−１次回折光Ｌ２４（−１）の強度Ｉ_１＋との差分を、＋１次回折光Ｌ２４（＋１）の強度Ｉ_１＋と−１次回折光Ｌ２４（−１）の強度Ｉ_１＋との総和によって正規化することで算出される。このため、第１非対称パラメータから計測光Ｌ２２の強度のばらつきによる影響が排除される。

The first asymmetric parameter shown in Equation 1 is calculated for each alignment mark M. Here, when the intensity of the measurement light L22 varies, the intensity of the measurement light L22 irradiated on one alignment mark M and the intensity of the measurement light L22 irradiated on the other alignment mark M do not match. there is a possibility. _{Therefore, if the first asymmetric parameter is simply the difference between the intensity I 1+} of the +1st order diffracted light L24 (+1) and the intensity I ₁₊ of the -1st order diffracted light L24 (-1), the first asymmetric parameter is aligned. There is a possibility that the measurement light L22 will fluctuate due to the variation in intensity, not due to the asymmetry of the mark M. That is, the first asymmetric parameter corresponding to one alignment mark M and the first asymmetric parameter corresponding to the other alignment mark M cannot be appropriately comparable parameters due to the variation in the intensity of the measurement light L22. there is a possibility. _{However, in the present embodiment, the first asymmetric parameter is the difference between the intensity I 1+} of the +1st-order diffracted light L24 (+1) and the intensity I ₁₊ of the -1st-order diffracted light L24 (-1), and the +1st-order diffracted light L24 (+1). intensity _{I 1+} and -1 are calculated by normalizing the sum of the intensities _{I 1+} order diffracted light L24 (-1). Therefore, the influence of the variation in the intensity of the measurement light L22 is excluded from the first asymmetric parameter.

On the other hand, as described above, when the measurement light L22 is obliquely incident on the substrate 141, the measurement light L22 is irradiated twice in order to emit ± primary diffracted light L24 (± 1) from the alignment mark M. Will be done. Therefore, when the intensity of the measurement light L22 varies, the intensity of the measurement light L22 irradiated when the +1st-order diffracted light L24 (+1) is emitted from the alignment mark M is changed to the -1st-order diffracted light L24 (-1). ) May not match the intensity of the emitted measurement light L22 when emitted from the alignment mark M. Therefore, when the measurement light L22 is obliquely incident on the substrate 141, the control device 29 uses the formula 2 instead of the formula 1 in order to eliminate the influence of the variation in the intensity of the measurement light L22. 1 Asymmetric parameters may be calculated. In Equation 2, the intensity of the 0th-order reflected light L24 (0) emitted from the alignment mark M together with the + 1st-order diffracted light L24 (+1) and the reflection region 233d-1 is attenuated is set to I ₀₊ , and the -1st-order diffracted light L24 ( The intensity of the 0th-order reflected light L24 (0) emitted from the alignment mark M together with -1) and the reflected region 233d-1 being attenuated is set to I _{0 −} . However, the intensity of the 0th-order reflected light L24 (0) emitted from the alignment mark M together with the + 1st-order diffracted light L24 (+1) and the reflection region 233d-1 is not attenuated is set to I ₀₊ , and the -1st-order diffracted light L24 (-1). The intensity of the 0th-order reflected light L24 (0) emitted from the alignment mark M and the reflected region 233d-1 is not attenuated may be set _{to I 0 −.}

数式２では、±１次回折光Ｌ２４（±１）の夫々の強度が、０次反射光Ｌ２４（０）の強度によって正規化されている。その結果、計測光Ｌ２２の強度のばらつきによる影響が排除される。

In Equation 2, the intensity of each of the ± 1st-order diffracted light L24 (± 1) is normalized by the intensity of the 0th-order reflected light L24 (0). As a result, the influence of the variation in the intensity of the measurement light L22 is eliminated.

In addition, in the formula 2, when the strength I ₀₊ = the strength I _{0 −} , the formula 2 corresponds to the formula 1. Therefore, even in Equation 1, the influence of the variation in the intensity of the measurement light L22 is still excluded. That is, in the present embodiment, the difference between the intensity of the +1st-order diffracted light L24 (+1) and the intensity of the -1st-order diffracted light L24 (-1) is normalized to the normalized intensity of the +1st-order diffracted light L24 (+1). It is equivalent to the difference from the intensity of the first-order diffracted light L24 (-1). As a result, for example, the intensity of the measurement light L22 irradiated on one alignment mark M and the intensity of the measurement light L22 irradiated on the other alignment mark M do not match due to the variation in the intensity of the measurement light L22. Even in this case, the influence of the variation in the intensity of the measurement light L22 is excluded from the first asymmetric parameter. Alternatively, for example, due to the variation in the intensity of the measurement light L22, the intensity of the measurement light L22 irradiated on the alignment mark M corresponding to one shot region and the alignment mark M corresponding to the other shot region were irradiated. Even when the intensity of the measurement light L22 does not match, the influence of the variation in the intensity of the measurement light L22 is excluded from the first asymmetric parameter.

Further, the control device 29 calculates the second asymmetric parameter using the mathematical formula 3. Note that in Equation 3, the second asymmetry parameter and P2, the strength of the reflection area 233 d-1 is attenuated (or not attenuated) zero-order reflected light L24 (0) and _{I 0.} However, when the measurement light L22 is obliquely incident on the substrate 141, the control device 29 uses the formula 4 instead of the formula 3 in order to eliminate the influence of the variation in the intensity of the measurement light L22. 2 Asymmetric parameters may be calculated. In addition, in the formula 4, when the strength I ₀₊ = the strength I _{0 −} , the formula 4 corresponds to the formula 3. Therefore, even in Equation 4, the influence of the variation in the intensity of the measurement light L22 is still excluded. In both Equations 3 and 4, the second asymmetric parameter is the average of the intensity of the normalized + 1st-order diffracted light L24 (+1) and the intensity of the normalized -1st-order diffracted light L24 (-1). It shows that it is equivalent to.

このように算出された第１及び第２非対称パラメータは、アライメントマークＭの非対称性の度合いを示すパラメータとなる。以下、図１１（ａ）から図１１（ｄ）を参照しながら、第１及び第２非対称パラメータとアライメントマークＭの非対称性との関係について説明する。

The first and second asymmetry parameters calculated in this way are parameters indicating the degree of asymmetry of the alignment mark M. Hereinafter, the relationship between the first and second asymmetry parameters and the asymmetry of the alignment mark M will be described with reference to FIGS. 11 (a) to 11 (d).

11 (a) and 11 (b) show that the asymmetry (shape distortion) of the alignment mark M can be replaced with a simple model. Specifically, as shown in FIG. 11A, as an example of the asymmetrical alignment mark M, there is an alignment mark M in which the shape of the bottom surface (bottom) of the groove is distorted (that is, it is not horizontal). As shown in the lowermost part of FIG. 11A, the shape of such a bottom surface can be replaced with a model having two horizontal bottom surfaces having different depths. Similarly, as shown in FIG. 11B, as an example of the asymmetrical alignment mark M, the alignment mark M in which the shape of the top surface (top) of the wall (mountain) is distorted (that is, it is not horizontal) is given. Be done. Such a top surface shape can be replaced with a model having two horizontal top surfaces having different heights, as shown in the lowermost part of FIG. 11B. In addition, the distortion of the shape of the side surface of the groove and the distortion of the shape of the side surface of the wall (furthermore, the distortion of any shape related to the groove and the wall) can be replaced with the models shown in FIGS. 11 (a) and 11 (b). be. Each of these distortions corresponds to a shape distortion including asymmetry with the optical axis of the objective optical system 205 as the axis of symmetry.

The actual alignment mark M has a mark structure depending on the semiconductor process. For example, the alignment mark M is not only a structure corresponding to a groove in which the shape of the bottom surface is distorted and a structure corresponding to a wall in which the shape of the top surface is distorted, but also a part of a metal layer formed in the groove or the like. It may have a structure or the like in which a transparent pattern portion is formed on the surface. Even in this case, the transparent pattern portion exhibits the same effect as the above-mentioned step (for example, the above-mentioned bottom surface having a different depth and the above-mentioned top surface having a different height). That is, in this case, the shape of the bottom surface or the top surface of the transparent pattern portion is distorted.

In the present embodiment, as parameters indicating the degree of asymmetry of the alignment mark M, a parameter called a bottom step (top step) corresponding to the difference in depth between the two bottom surfaces or the difference in height between the two top surfaces and 2 Pay attention to the parameter of the mark step corresponding to the average depth of one bottom surface or the average height of two top surfaces. For example, the bottom step and the mark step of a model having a bottom surface having a depth of A and a bottom surface having a depth of B (however, B> A) are "BA" and "(A + B) / 2, respectively. ". For example, the bottom step (top step) and the mark step of a model having a top surface having a height of A and a top surface having a height of B (however, B> A) are "BA" and mark, respectively. It becomes "(A + B) / 2".

As shown in FIG. 11C, the bottom step correlates with the first asymmetric parameter (that is, the difference between the intensity of the +1st-order diffracted light L24 (+1) and the intensity of the -1st-order diffracted light +24 (-1)). It becomes a parameter. That is, it can be said that the first asymmetry parameter substantially indicates the bottom step indicating the degree of asymmetry of the alignment mark M. Further, as shown in FIG. 11D, the mark step has the intensity of the +1st-order diffracted light L24 (+1) and the -1st-order diffracted light L24 (that is, the intensity of the 0th-order reflected light L24 (0) with respect to the intensity of the 0th-order reflected light L24 (0). It is a parameter that has a correlation with -1) the ratio of the average value to the intensity). That is, it can be said that the second asymmetry parameter substantially indicates a mark step indicating the degree of asymmetry of the alignment mark M. Here, the mark step may be referred to as mark height.

Therefore, the first and second asymmetric parameters correspond to information that can identify whether or not the shape of the alignment mark M is asymmetric. Furthermore, it can be said that the first and second asymmetric parameters are information that can estimate to some extent what kind of shape the asymmetric shape of the alignment mark M is.

Conversely, if the first asymmetric parameter is calculated but the second asymmetric parameter is not calculated, it becomes difficult to estimate what the asymmetric shape of the alignment mark M is. there is a possibility. For example, FIG. 12 shows a series of alignment marks M whose shape changes so that the mark step changes while maintaining a state where the bottom step is constant. From such an alignment mark M, the first and second asymmetric parameters shown on the right side of FIG. 12 are calculated. In this case, since the first asymmetric parameter does not change (that is, has a constant value), the first asymmetric parameter is an alignment mark M in which the series of alignment marks M shown on the left side of FIG. 12 all have the same shape. It is shown that. However, in reality, since the shapes of the series of alignment marks M are all different, the position of the alignment mark M and the original alignment mark indicated by the mark position information obtained by the alignment measurement, as shown by the thick line on the left side of FIG. The error from the position of M varies depending on the shape of the alignment mark M. Therefore, it is difficult to suppress the influence of the asymmetry of the alignment mark M on the mark position information by the first asymmetry parameter alone in some cases.

Similarly, if the second asymmetric parameter is calculated but the first asymmetric parameter is not calculated, it may be difficult to estimate what the asymmetric shape of the alignment mark M is. There is. For example, FIG. 13 shows a series of alignment marks M whose shape changes so that the bottom step changes while maintaining a state in which the mark step is constant. From such an alignment mark M, the first and second asymmetric parameters shown on the right side of FIG. 13 are calculated. In this case, since the second asymmetric parameter does not change (that is, has a constant value), the second asymmetric parameter is an alignment mark M in which the series of alignment marks M shown on the left side of FIG. 12 all have the same shape. It is shown that. However, in reality, since the shapes of the series of alignment marks M are all different, the mark position information may include an error that varies depending on the shape of the alignment marks M. Therefore, it is difficult to suppress the influence of the asymmetry of the alignment mark M on the mark position information by the second asymmetry parameter alone in some cases.

However, in the present embodiment, since both the first and second asymmetric parameters are calculated, one of the first and second asymmetric parameters is calculated, but the other of the first and second asymmetric parameters is calculated. It is possible to eliminate the influence of the asymmetry of the alignment mark M on the mark position information as compared with the case where is not calculated.

After calculating the asymmetric parameter, the control device 29 corrects the mark position information based on the calculated asymmetric parameter. Specifically, the control device 29 determines a predetermined value according to the asymmetry parameter so as to reduce or eliminate the error component that may remain in the mark position information due to the asymmetry of the shape of the alignment mark M. The mark position information is corrected by performing the arithmetic processing of the above on the mark position information. After that, the control device 29 performs the EGA calculation based on the corrected mark position information. As a result, the above-mentioned alignment parameters (that is, the coefficients (a ₀ , a ₁ , a ₂ , a ₃ , a ₄ , a ₅ , a ₆ , a ₇ , a ₈ , a ₉ , ... , B ₀ , b ₁ , b ₂ , b ₃ , b ₄ , b ₅ , b ₆ , b ₇ , b ₈ , b ₉ ...)).

After that, the control device 29 transmits the calculated alignment parameter to the storage device 4. The storage device 4 stores the alignment parameter transmitted by the control device 29 together with the identification information for identifying the substrate 141 from which the alignment parameter has been acquired. After that, the substrate 141 is transported from the alignment device 2 to the exposure device 1 by the transfer device.

The control device 16 included in the exposure device 1 to which the substrate 141 is transported acquires the mark position information by using the alignment system 15. The mark position information acquisition operation performed by the alignment system 15 is the same as the mark position information acquisition operation performed by the alignment device 2. Further, the control device 16 acquires the alignment parameter stored in the storage device 4. When the alignment parameter stored in the storage device 4 is acquired, the control device 16 may perform a simple EGA calculation for calculating a part of the alignment parameter. The exposure apparatus 1 can use the alignment parameters calculated by the alignment apparatus 2 as they are for the other part of the alignment parameters.

For example, the control device 16 has coefficients (a ₃ , a ₄ , a ₅ , a ₆ , a ₇ , a ₈ , a ₉ , ..., b ₃ , b ₄ , b) of higher-order components of the alignment parameters. _{For 5} , b ₆ , b ₇ , b ₈ , b ₉ ...), the alignment parameters calculated by the alignment device 2 may be used as they are. Since the coefficient of the high-order component _{(a 3, a 4, a} 5, a 6, a 7, a 8, a 9, ···, b 3, b 4, b 5, b 6, b 7, b ₈ , b ₉ ...) Are components generated mainly due to the deformation of the substrate 141 due to the process, and there is a high possibility that the substrate 141 will not change even if the substrate 141 is transported from the alignment device 2 to the exposure device 1. Because. In this case, if the control device 16 performs a simple EGA operation for calculating _{the coefficients (a 0} , a ₁ , a ₂ , b ₀ , b ₁ , b _{2) of the low-order components of the alignment parameters.} good. The coefficients of the low-order components (a ₀ , a ₁ , a ₂ , b ₀ , b ₁ , b ₂ ) are components that are mainly caused by the deformation of the substrate 141 due to the holding state of the substrate 141 by the substrate stage 14. This is because there is a possibility that the change may occur due to the transition from the state in which the substrate stage 27 of the alignment device 2 holds the substrate 141 to the state in which the substrate stage 14 of the exposure apparatus 1 holds the substrate 141.

As a result of the above operation, the control device 16 acquires the alignment parameter. Here, the alignment parameter includes a parameter component calculated based on the mark position information corrected by the asymmetric parameter. Therefore, the control device 16 can calculate the alignment parameter with relatively high accuracy as compared with the case where the mark position information is not corrected based on the asymmetric parameter.

The configuration of the exposure system SYS described above (for example, the shape, arrangement position, size, function, number, etc. of each device (or each member constituting each device) constituting the exposure system SYS) is It is just an example. Therefore, at least a part of the configuration of the exposure system SYS may be appropriately modified. Hereinafter, some of the modified examples will be described.

When the ± Kth-order diffracted light L24 (± K) is incident on the image pickup element 25, the control device 29 determines the difference between the intensity of the + Kth-order diffracted light L24 (+ K) and the intensity of the −Kth-order diffracted light L24 (−K). Alternatively, an arbitrary coefficient that can be calculated from the difference) may be adopted as the first asymmetric parameter. The control device 29 calculates the ratio of the average value of the intensity of the + Kth-order diffracted light L24 (+ K) to the intensity of the −Kth-order diffracted light L24 (−K) with respect to the intensity of the 0th-order reflected light L24 (0) (or calculated from the ratio). Any possible coefficient) may be adopted as the second asymmetric parameter.

The control device 29 determines the ratio of the intensity of the + 1st-order diffracted light L24 (+1) or the + K-th-order diffracted light L24 (+ K) to the intensity of the 0th-order reflected light L24 (0) (or an arbitrary coefficient that can be calculated from the ratio). It may be adopted as the second asymmetric parameter. The control device 29 is a ratio of the intensity of the -1st-order diffracted light L24 (-1) or the −K-order diffracted light L24 (−K) to the intensity of the 0th-order reflected light L24 (0) (or any ratio that can be calculated from the ratio. Coefficient) may be adopted as the second asymmetric parameter. The control device 29 may adopt the intensity of the 0th-order reflected light L24 (0) itself (or an arbitrary coefficient that can be calculated from the intensity) as the second asymmetric parameter. The control device 29 may adopt the intensity of the + 1st-order diffracted light L24 (+1) or the + K-th order diffracted light L24 (+ K) itself (or an arbitrary coefficient that can be calculated from the intensity) as the second asymmetric parameter. The control device 29 adopts the intensity of the -1st order diffracted light L24 (-1) or the −K order diffracted light L24 (−K) itself (or an arbitrary coefficient that can be calculated from the intensity) as the second asymmetric parameter. May be good.

In the above description, the first and second asymmetric parameters are calculated from the intensity of the normalized +1st order diffracted light L24 (+1) and the intensity of the normalized -1st order diffracted light L24 (-1). However, the first and second asymmetric parameters may be calculated from the intensity of the unnormalized +1st order diffracted light L24 (+1) and the intensity of the unnormalized -1st order diffracted light L24 (-1).

The first asymmetric parameter does not have to be the difference between two types of diffracted light L24 of the same order. The first asymmetric parameter may be a parameter relating to the relationship between two types of diffracted light L24 of the same order. The first asymmetric parameter may be a parameter relating to the relationship between two types (or three or more types) of diffracted light L24 having different orders.

The illumination system 21 may be movable on the emission end face of the light guide 217 along the optical axis of the illumination system 21.

The variable field diaphragm 231 may include other diaphragm mechanisms in addition to or in place of the diaphragm mechanisms 2311 to 2314. For example, the variable field diaphragm 231 may include a diaphragm mechanism capable of adjusting the distance between two openings arranged along the X-axis direction.

The diaphragm blade 2314a included in the diaphragm mechanism 2314 may not include either the second blade portion 2314a-2 or the third blade portion 2314a-3. The diaphragm blade 2314b does not have to include either the second blade portion 2314b-2 or the third blade portion 2314b-3. Even in this case, the diaphragm mechanism 2314 can define two openings arranged along the directions intersecting both the X-axis direction and the Y-axis direction. For example, as shown in FIG. 14A, even when the diaphragm blade 2314a does not include the second blade portion 2314a-2 and the diaphragm blade 2314b does not include the second blade portion 2314b-2. The diaphragm mechanism 2314 can define two openings (openings equivalent to the two openings shown in FIG. 8B) arranged along a direction intersecting both the X-axis direction and the Y-axis direction. For example, as shown in FIG. 14B, even when the diaphragm blade 2314a does not include the third blade portion 2314a-3 and the diaphragm blade 2314b does not include the third blade portion 2314b-3. The diaphragm mechanism 2314 can define two openings (openings equivalent to the two openings shown in FIG. 8D) arranged along a direction intersecting both the X-axis direction and the Y-axis direction.

At least one of the light guide optical systems 23 and 24 does not have to include the variable field diaphragm 231. For example, when the measurement light L22 is not applied to both the grid mark MX and the grid mark MY at the same time, at least one of the light guide optical systems 23 and 24 does not have to include the variable field diaphragm 231.

At least one of the light guide optical systems 23 and 24, in addition to or in place of the Kester prism 233, attenuates a part of the emitted light L24 by a predetermined amount or more, and attenuates a predetermined amount or more of the emitted light L24 and a predetermined amount or more. Any optical element that guides both the unattenuated emitted light L24 to the image pickup element 25 may be provided. At least one of the light guide optical systems 23 and 24 can attenuate the emitted light L24 branched in two directions and the emitted light branched in one direction by a predetermined amount or more instead of the Kester prism 233. It may be provided separately from the optical element.

The light guide optical system 23 does not have to attenuate a part of the emitted light L24 by a predetermined amount or more. While the light guide optical system 23 guides the emitted light L24 that has not been attenuated by a predetermined amount or more to the image pickup device 25, the light guide optical system 23 does not have to guide the emitted light L24 that has been attenuated by a predetermined amount or more to the image pickup element 25. In this case, the image pickup surface 25a of the image pickup device 25 includes the first image pickup area 25a-1, but does not have to include the second image pickup area 25a-2. Alternatively, the light guide optical system 23 does not have to guide the emitted light L24 attenuated by a predetermined amount or more to the image sensor 25, while the emitted light L24 not attenuated by a predetermined amount or more is guided to the image sensor 25. In this case, the image pickup surface 25a of the image pickup device 25 includes the second image pickup area 25a-2, but does not have to include the first image pickup area 25a-1. The same applies to the light guide optical system 24 and the image sensor 26.

The alignment device 2 may not include any light receiving element capable of receiving the emitted light L24 in addition to or in place of at least one of the image pickup elements 25 and 26. The alignment device 2 includes a light receiving element that receives the 0th-order reflected light L24 (0), a light receiving element that receives the + 1st-order diffracted light L24 (+1), and a light receiving element that receives the -1st-order diffracted light L24 (-1). You may have it. In this case, the alignment device 2 determines the light receiving result of each light receiving element as the intensity of the 0th-order reflected light L24 (0), the intensity of the + 1st-order diffracted light L24 (+1), and the intensity of the -1st-order diffracted light L24 (-1), respectively. It may be treated as.

In the above description, the alignment device 2 corrects the mark position information acquired by the alignment measurement performed by the alignment device 2 based on the asymmetric parameter. However, the alignment device 2 may correct the mark detection information or the alignment parameter acquired by the alignment measurement performed by the alignment device 2 based on the asymmetry parameter. Alternatively, in addition to or in place of the alignment device 2, the exposure device 1 may correct the mark detection information, the mark position information, or the alignment parameter acquired by the alignment measurement performed by the exposure device 1 based on the asymmetry parameter. .. In this case, the alignment device 2 may store the calculated asymmetric parameter in the storage device 4. The exposure device 1 may acquire the asymmetric parameter stored in the storage device 4.

As shown in FIG. 15A, the exposure system SYS may include a superposition measuring device 5. The superposition measuring device 5 measures the superposition error of the device pattern transferred by the exposure device 1. The substrate 141 is transported from the substrate processing device 3 to the superposition measuring device 5 by a transport device (not shown). The superposition measurement device 5 detects a measurement mark image formed on a certain layer of the conveyed substrate, and the amount of positional deviation between the detected measurement mark image and the measurement mark image formed on a different layer. (Superposition error) is calculated. Here, as shown in FIG. 15B, there may be a correlation between the superposition error calculated by the superposition measuring device 5 and the asymmetric parameter described above. In this case, it is highly probable that the asymmetry of the alignment mark M affects the accuracy of the alignment measurement performed by the exposure apparatus 1. Therefore, when there is a correlation between the superposition error and the asymmetric parameter, the exposure apparatus 1 may refer to the asymmetric parameter when performing the alignment measurement. That is, the exposure apparatus 1 may correct the mark position information acquired by the alignment measurement performed by the exposure apparatus 1 based on the asymmetric parameter. As a result, since the adverse effect caused by the asymmetry of the alignment mark M is further eliminated, it is possible to further reduce the superposition error having a correlation with the asymmetry of the alignment mark M. Of course, even when there is no correlation between the superposition error and the asymmetric parameter, the exposure apparatus 1 may correct the mark position information acquired by the alignment measurement performed by the exposure apparatus 1 based on the asymmetry parameter. ..

In the above description, the exposure apparatus 1 exposes a substrate 141 such as a semiconductor substrate. However, the exposure apparatus 1 may expose any object such as a glass plate, a ceramic substrate, a film member, or a mask blank. The exposure apparatus 1 may be an exposure apparatus for manufacturing a liquid crystal display element or a display. The exposure apparatus 1 may be an exposure apparatus for manufacturing at least one of a thin film magnetic head, an image pickup device (for example, a CCD), a micromachine, a MEMS, a DNA chip, and a mask 111 (or a reticle). The exposure device EX may be an optical tweezers device that captures an object by using the light trapping force generated in the object by irradiating the object with the exposure light EL.

A device such as a semiconductor device may be manufactured through each step shown in FIG. The steps for manufacturing the device include step S201 for manufacturing the function and performance of the device, step S202 for manufacturing the mask 111 based on the function and performance design, step S203 for manufacturing the substrate 141 which is the base material of the device, and the mask. Step S204 for exposing the substrate 141 with the exposure light EL from the device pattern 111 and developing the exposed substrate 141, step S205 including device assembly processing (processing processing such as dicing processing, bonding processing, packaging processing), and inspection. Step S206 may be included.

The requirements of each of the above embodiments can be combined as appropriate. Some of the requirements of each of the above embodiments may not be used. The requirements of each of the above embodiments can be replaced with the requirements of other embodiments as appropriate. In addition, to the extent permitted by law, the disclosures of all published gazettes and US patents relating to the exposure apparatus and the like cited in each of the above-described embodiments shall be incorporated as part of the description of the main text.

Further, the present invention can be appropriately changed within the scope of the claims and within the range not contrary to the gist or idea of the invention that can be read from the entire specification, and the position detection device and the position detection method, the exposure device and the exposure device accompanied by such a change. The exposure method and the device manufacturing apparatus are also included in the technical idea of the present invention.

1 Exposure device 14 Substrate stage 141 Substrate 143 Position measurement device 15 Alignment system 16 Control device 2 Measuring device 21 Lighting system 23, 24 Guide optical system 231 Variable field aperture 233 Kester prism 25, 26 Imaging element 25a Imaging surface 25a-1, 25a-2 Imaging area 27 Board stage 271 Position measuring device 29 Control device M Alignment mark

Claims (39)

A position detection device that detects the position of a mark formed on an object with the measurement light from a light source.
A detector that detects at least a first-order diffracted light and a second-order diffracted light different from the first-order diffracted light among a plurality of diffracted light of the measured light via the mark.
With a controller that calculates error information regarding position detection error due to the asymmetry of the shape of the mark and the height of the surface of the mark using the detection result of the detector, and corrects the position information regarding the detection position of the mark. A position detector comprising. A position detection device that detects the position of a mark formed on an object with the measurement light from a light source.
A detector that detects at least a first-order diffracted light and a second-order diffracted light different from the first-order diffracted light among a plurality of diffracted light of the measured light via the mark.
Using the detection result of the detector, a controller that calculates the position information regarding the detection position of the mark and also calculates the error information regarding the position detection error due to the asymmetry of the shape of the mark and the height of the surface of the mark. A position detector with and. The position detection device according to claim 1 or 2, wherein the first-order diffracted light and the second-order diffracted light reach positions separated from each other on the detection surface of the detector. The position detection device according to any one of claims 1 to 3, wherein the detector detects the 0th-order light of the measurement light via the mark. The error information is described in any one of claims 1 to 4 regarding the detection error due to the asymmetry of the mark with respect to the axis of symmetry along the optical axis of the light guide optical system that guides the measurement light to the mark. Position detector. The one according to any one of claims 1 to 5, wherein the detector includes first and second detectors that detect at least a part of a plurality of diffracted light of the measurement light via the mark. Position detector. The position detection device according to claim 6, wherein the controller detects the position of the mark using the detection result of the first detector and calculates the error information using the detection result of the second detector. .. The position detection device according to claim 7, wherein the controller uses the error information to change the detection result of the first detector. Any of claims 6 to 8 , wherein the second detector independently detects ± N (where N is an integer of 1 or more) order diffracted light of the measured light as diffracted light of the first order and the second order. The position detection device according to one item. The position detection device according to claim 9 , wherein the controller calculates the error information by using the relationship between the detection result of the + Nth-order diffracted light and the detection result of the −Nth-order diffracted light. The second detector detects the reflected light of the measurement light and
The position detection device according to claim 9 or 10 , wherein the controller calculates the error information by using the relationship between the detection result of the reflected light and the detection result of at least one of the + Nth-order diffracted light and the −Nth-order diffracted light. The detector detects the reflected light of the measurement light, the diffracted light of the first order, and the diffracted light of the second order through the mark.
The controller has at least one of the first information regarding the relationship between the intensity of the diffracted light of the first order and the diffracted light of the second order, the reflected light, the diffracted light of the first order, and the diffracted light of the second order. The position detection device according to any one of claims 1 to 11 , which calculates the error information based on the second information regarding the strength. The position detecting device according to claim 12 , wherein the first information is a difference in intensity of diffracted light between the first order and the second order. The second information is the intensity of the reflected light, the intensity of at least one of the diffracted light of the first order and the second order, and the diffracted light of the first order and the second order normalized by the intensity of the reflected light. The position detecting apparatus according to claim 12 or 13 , relating to at least one intensity and at least one of the intensity of the reflected light normalized by the intensity of at least one of the first-order and second-order diffracted light. .. Any of claims 12 to 14 , wherein the detector detects at least each of + N (where N is an integer of 1 or more) order diffracted light and −N order diffracted light as the diffracted light of the first order and the second order. The position detection device according to one item. An irradiation optical system that irradiates the mark with the measurement light from the light source is further provided.
The position detection device according to any one of claims 1 to 15 , wherein the irradiation optical system can irradiate the object with the measurement light from an oblique direction. Further provided with an attenuation member that attenuates at least a part of the reflected light of the measurement light, the diffracted light of the first order, and the diffracted light of the second order through the mark.
In the detector, the first reflected light component in which the attenuating member is attenuated in the reflected light passing through the mark and the attenuating member in the diffracted light of the first order and the second order through the mark are attenuated. The position detection device according to any one of claims 1 to 16 , which detects the first diffracted light component. The detector uses the second reflected light component in which the attenuating member is not attenuated in the reflected light passing through the mark, and the attenuating member in the diffracted light of the first order and the second order through the mark. The position detecting apparatus according to claim 17 , wherein the second diffracted light component which is not attenuated is detected. The controller comprises first information regarding the intensities of the two types of second diffracted light components detected by the detector, the reflected light detected by the detector, the diffracted light of the first order, and the second diffracted light. The position detecting apparatus according to claim 18 , further comprising calculating the error information based on the second information regarding the intensity of at least one of the diffracted light. The first information relates to the relationship between the intensities of the two types of the second diffracted light components.
The position detection device according to claim 19 , wherein the second information relates to the intensity of the first reflected light component and the intensity of the second diffracted light component. The first information relates to the difference in intensity between the two types of second diffracted light components.
The second information includes the intensity of the second diffracted light component normalized by the intensity of the first reflected light component and the intensity of the first reflected light component normalized by the intensity of the second diffracted light component. The position detection device according to claim 20 , wherein the position detection device relates to at least one of them. The detector has a first detection region for detecting the first reflected light component and the first diffracted light component, and a second detection for detecting the second reflected light component and the second diffracted light component. The position detecting device according to any one of claims 18 to 21 , which includes a region. A branch member for branching the optical path of the reflected light, the diffracted light of the first order, and the diffracted light of the second order through the mark into a plurality of optical paths is provided.
The position detecting device according to any one of claims 17 to 22 , wherein the damping member is arranged in one of the plurality of optical paths. A light-shielding member that shields a part of the reflected light of the measurement light, the diffracted light of the first order, and the diffracted light of the second order through the mark is further provided.
The position detecting device according to any one of claims 1 to 23 , wherein the detector detects the reflected light, the diffracted light of the first order, and the diffracted light of the second order via the light-shielding member. The light-shielding member shields at least a part of the reflected light, the first-order diffracted light, and the second-order diffracted light through the first mark of the marks, while the light-shielding member of the marks. The position detection device according to claim 24 , which does not block the reflected light, the diffracted light of the first order, and the diffracted light of the second order through a second mark different from the first mark. The position detecting device according to claim 24 or 25 , wherein the light-shielding member is movable. An irradiation optical system that irradiates the mark with the measurement light from the light source is further provided.
The irradiation optical system uses a first irradiation unit that irradiates the mark with the measurement light from the light source at a first angle with respect to the normal of the object, and the measurement light from the light source of the object. The position detection device according to any one of claims 1 to 26 , which includes a second irradiation unit that irradiates the mark at a second angle different from the first angle with respect to the normal. The irradiation optical system selects either the first or second irradiation unit as the irradiation unit to irradiate the measurement light, based on the pitch of the lattice pattern constituting the mark to which the measurement light is irradiated. The position detection device according to claim 27. The position detecting device according to claim 27 or 28 , wherein the first angle is 0 degrees and the second angle is larger than 0 degrees. The position detection device according to any one of claims 27 to 29 , wherein the irradiation optical system includes a plurality of the second irradiation units. The position detection device according to claim 30 , wherein the measurement light is sequentially irradiated from the plurality of second irradiation units. The detector, said via said mark measurement light of the reflected light, in any one of claims 1 to 31 comprising an imaging device for imaging the diffracted light of the diffracted light and the second order number of the 1st order The described position detector. The controller
By performing a fitting process on the image pickup result of the image pickup element using a template showing at least one ideal intensity distribution of the reflected light, the first-order diffracted light, and the second-order diffracted light. , The imaging information regarding at least one of the reflected light, the diffracted light of the first order, and the diffracted light of the second order is extracted from the imaging result.
Claim that the intensity of at least one of the reflected light, the diffracted light of the first order and the diffracted light of the second order is calculated based on the extracted imaging information, and the error information is calculated based on the calculated intensity. 32. The position detection device. Further equipped with another detector for detecting other measurement light via the mark from another light source.
The controller calculates the position information using the detection results of the other detectors, and then calculates the position information.
The position detection device according to any one of claims 1 to 33 , wherein the controller corrects the position information based on the error information. The position detecting device according to any one of claims 1 to 34 , wherein the mark is formed of a plurality of grid marks, and the asymmetry of the shape of the mark is an asymmetry of the plurality of grid marks in the pitch direction. The position detecting device according to any one of claims 1 to 35 , wherein the asymmetry of the shape of the mark is an asymmetry in the in-plane direction in which the plurality of diffracted lights travel. An exposure apparatus that exposes an object using the detection result of the position detection apparatus according to any one of claims 1 to 36. An exposure method for exposing an object using the detection result of the position detection device according to any one of claims 1 to 36. The object coated with the photosensitizer is exposed by using the exposure method according to claim 38, and a desired pattern is transferred to the object.
The exposed photosensitizer is developed to form an exposure pattern layer corresponding to the desired pattern.
A device manufacturing method for processing an object through the exposure pattern layer.

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