JP7241564B2 - Exposure apparatus and article manufacturing method - Google Patents

Description

The present invention relates to an exposure apparatus and an article manufacturing method.

2. Description of the Related Art An exposure apparatus that exposes a substrate may be used in a manufacturing process (lithography process) for semiconductor devices and the like. In an exposure apparatus, for example, a shutter having a light shielding member that blocks light from a light source is provided, and the exposure amount of the substrate is controlled by driving the shutter to switch between irradiation and non-irradiation of light to the substrate. be able to.

Japanese Patent Application Laid-Open No. 2004-200000 discloses a method of detecting a half-open shutter due to a shutter drive error such as an encoder miscount or a decrease in air pressure. In the method described in Patent Document 1, a deviation between a counter value (voltage value of a signal from a light receiving element) when shutter closed information is input and a counter value when shutter open information is input is obtained, Half-opening of the shutter is detected by comparing the deviation with a reference value.

JP-A-6-53109

In the shutter of the exposure apparatus, when the light shielding member is irradiated with high-energy light, the light shielding member deteriorates, and an abnormality such as partial loss (damage) or thinning of the light shielding member may occur. In this case, even if the shutter is normally driven so that the light shielding member is arranged in the optical path of the light from the light source, light leaks from a part of the light shielding member that has an abnormality such as a defect or thinning. Such leaked light can make it difficult to control the exposure amount of the substrate with high accuracy in the recent demand for finer circuit patterns. Therefore, in the exposure apparatus, it is desired to detect leakage light from the light shielding member and accurately detect an abnormality of the light shielding member.

However, the cross-sectional area and light intensity of leaked light from a light shielding member that has an abnormality such as a defect or thinning is very small. For this reason, it may be difficult to detect the leaked light in the method of using the deviation of the counter value between when the shutter closed information is input and when the shutter open information is input, as in Patent Document 1.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an exposure apparatus that is advantageous for accurately detecting an abnormality in a light shielding member.

To achieve the above object, an exposure apparatus as one aspect of the present invention is an exposure apparatus for exposing a substrate, comprising a shutter having a first light shielding member for blocking light from a light source, and a light beam passing through the shutter. a detection unit that detects the light; and a control unit that controls exposure processing of the substrate by driving the shutter, wherein the control unit includes the first light shielding member arranged in the optical path of the light. A detection result of the detection unit in a first state, and a detection result of the detection unit in a second state in which the first light blocking member is not arranged in the optical path of the light and the light is blocked from entering the detection unit. An abnormality of the first light shielding member is detected by comparing the detection result.

Further objects or other aspects of the present invention will be made clear by preferred embodiments described below with reference to the accompanying drawings.

According to the present invention, for example, it is possible to provide an exposure apparatus that is advantageous for accurately detecting an abnormality in a light shielding member.

Schematic diagram showing a configuration example of an exposure apparatus FIG. 4 is a diagram showing the relationship between the driving state of the shutter and the illuminance of the light applied to the substrate; FIG. 5 is a diagram showing the correspondence relationship between the drive state of the shutter and the detection result of the detection unit; Flowchart showing a method for detecting an abnormality in the first light shielding member A diagram showing the correspondence relationship between light, the number of times each light blocking member 31 is placed on the road, and the detection result of the detection unit. A diagram showing an exposure apparatus having a second light shielding member 14 is a flowchart showing substrate exposure processing in the fourth embodiment; A diagram showing an example of shutter rotation drive A diagram showing a light shielding member (before change) used for exposure processing of each shot area. A diagram showing a light shielding member (after change) used for exposure processing of each shot area. Flowchart showing substrate exposure processing in the fifth embodiment Flowchart showing substrate exposure processing in the sixth embodiment

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. In addition, the following embodiments do not limit the invention according to the scope of claims. Although multiple features are described in the embodiments, not all of these multiple features are essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant description is omitted.

<First embodiment>
A first embodiment according to the present invention will be described. FIG. 1 is a schematic diagram showing a configuration example of an exposure apparatus 100 of this embodiment. The exposure apparatus 100 is a lithography apparatus used in the manufacturing process (lithography process) of devices such as semiconductor elements, liquid crystal display elements, and thin-film magnetic heads as articles, and forms a pattern on a substrate by exposing the substrate. In this embodiment, the exposure apparatus 100 is a projection exposure apparatus that exposes a substrate by projecting a pattern image of an original (mask or reticle) onto the substrate by a stepper method or a scanning method, and transfers the pattern of the original to the substrate. can be However, the exposure apparatus 100 is not limited to this, and the exposure apparatus 100 exposes the substrate (imprint material) while the mold and the imprint material on the substrate are in contact with each other, thereby curing the imprint material and depositing the imprint material on the substrate. may be an imprint apparatus that forms a pattern of

The exposure apparatus 100 includes an illumination optical system IL that illuminates an original (not shown) with light from a light source unit LS, a projection optical system (not shown) that projects the pattern of the original onto a substrate, a detector 8, and a current driver. 10 , a frequency/voltage converter 11 and a voltage/frequency converter 12 . The exposure apparatus 100 also has a servo amplifier 13 , a multiplier 14 , a position counter 15 , an exposure amount counter 16 and a control section 17 .

The light source unit LS includes a light source 1 (for example, an ultraviolet lamp) that emits light (exposure light) for exposing a substrate, and an elliptical mirror 2 that collects the light from the light source 1 and guides it to the illumination optical system IL. . The illumination optical system IL also has a mechanism for controlling the time for illuminating the original with the light from the light source section LS (that is, the light irradiation time for the substrate). The mechanism includes a shutter 3, a lens 4, a half mirror 5, a motor 6, and an encoder 7, for example.

The shutter 3 is, for example, configured as a rotating body having a plurality of light blocking members 31 (blades, light blocking regions) that block light from the light source unit LS, and allows light to pass through light passing regions 32 between the plurality of light blocking members. The shutter 3 of the present embodiment is composed of three light shielding members 31 arranged at equal intervals (equal angles), but may be composed of two or four or more light shielding members 31, or may be composed of one light shielding member 31. It may be composed of the light shielding member 31 . A motor 6 is a drive source for rotating the shutter 3 . The encoder 7 is a measuring instrument for measuring the rotational position of the shutter 3 . Light passing through the shutter 3 is incident on the half mirror 5 via the lens 4 , and part of the light is guided to the detector 8 by the half mirror 5 . In the example shown in FIG. 1 , part of the light that has passed through the shutter 3 and is reflected by the half mirror 5 is guided to the detector 8 . The detection unit 8 includes a photodetector that detects the intensity of the part of the light guided from the half mirror 5, and its output measures the illuminance (intensity) of the light applied to the substrate and the exposure amount of the substrate. can be used to Here, the exposure amount of the substrate is defined by the time integral of the illuminance of the light with which the substrate is irradiated.

A current driver 10 supplies current to the motor 6 to drive the motor 6 . A frequency voltage converter (FVC) 11 converts a pulse train proportional to the rotation speed of the shutter output from the encoder 7 into a voltage. A voltage/frequency converter (VFC; Voltage Frequency Converter) 12 converts an analog voltage output from the detector 8 and proportional to the exposure amount of the substrate into a pulse train.

The servo amplifier 13 adjusts the actual rotational speed of the shutter 3 and the secondary command value 24 so that the actual rotational speed of the shutter 3 coincides with the secondary command value 24 (the rotational speed of the shutter 3 indicated by). An output proportional to the difference is provided to current driver 10 . A multiplier 14 generates a secondary command value 24 based on a primary command value 21 that indicates the rotation speed of the shutter 3 and the gain control data 20 .

A position counter 15 monitors the rotational position of the shutter 3 and outputs position data 22 . The exposure amount counter 16 counts the pulses output from the VFC 12 to monitor the temporally integrated amount of light incident on the detection unit 8 , that is, the exposure amount of the substrate, and outputs exposure amount data 23 .

The control unit 17 includes a CPU and a memory (storage unit), and comprehensively controls each unit of the exposure apparatus 100 to control exposure processing for each of a plurality of shot areas on the substrate. For example, in the exposure process, the control unit 17 controls irradiation and non-irradiation of light to the substrate by rotationally driving the shutter 3 so that the exposure amount of the substrate becomes the target exposure amount. Specifically, the control unit 17 shifts from the light shielding state in which the light from the light source unit LS is blocked by the light shielding member 31 to the light passing state in which the light from the light source unit LS passes through the light passing region 32. Then, the rotational drive of the shutter 3 is controlled so as to shift to the light shielding state again.

FIG. 2 is a diagram showing the relationship between the driving state of the shutter 3 and the illuminance of light applied to the substrate. In the exposure process, the rotation of the shutter 3 is started from the light shielding state (state (1) in FIG. 2) in which the light shielding member 31 of the shutter 3 is arranged on the optical path of the light from the light source unit LS. When the shutter 3 starts to rotate, light gradually begins to pass through the light passage area 32 of the shutter 3 (state (2) in FIG. 2), and the entire light passes through the light passage area 32. Rotation of the shutter 3 is stopped in the state (state (3) in FIG. 2). Then, the rotation of the shutter 3 is restarted so that the exposure amount of the substrate reaches the target exposure amount (state (4) in FIG. 2). When the shutter 3 starts to rotate, the light is gradually blocked by the light shielding member 31 (state (5) in FIG. 2), and the light shielding member 31 is placed on the optical path (state ( in FIG. 2)). At 6)), the rotation of the shutter 3 is stopped. Here, in the exposure process, the rotation of the shutter 3 is stopped in each of the light blocking state and the light passing state. may be performed continuously without stopping.

In the exposure apparatus 100 configured as described above, when the light shielding member 31 of the shutter 3 is irradiated with high-energy light, the light shielding member 31 is degraded, and part of the light shielding member 31 is lost (damaged) or thinned. There is In this case, even if the shutter 3 is normally driven so that the light shielding member 31 is arranged along the entire optical path of the light from the light source unit LS, the light will not be emitted from the part of the light shielding member 31 that is damaged, thinned, or otherwise damaged. leaks out. Although such leaked light has a very small cross-sectional area and light intensity, it may become difficult to control the exposure amount of the substrate with high accuracy in the recent demand for miniaturization of circuit patterns. Therefore, in the exposure apparatus 100, it is desired to detect leakage light from the light shielding member 31 of the shutter and to detect an abnormality of the light shielding member 31 with high accuracy.

Therefore, in the exposure apparatus 100 (control unit 17) of the present embodiment, the first light blocking member of the shutter 3 is not arranged on the optical path of the light from the light source unit LS, so that the light is blocked from entering the detection unit 8. A detection result of the detection unit 8 in the second state is obtained. Then, the detection result of the detection unit 8 in the first state in which the shutter 3 is driven so that the first light shielding member of the shutter 3 is arranged on the optical path is compared with the detection result of the detection unit 8 in the second state. By doing so, the abnormality of the first light shielding member is detected. Here, the first light shielding member is the light shielding member whose abnormality is to be detected, among the plurality of light shielding members 31 forming the shutter 3 . That is, when an abnormality is detected for each of the plurality of light shielding members 31 forming the shutter 3, each of the plurality of light shielding members 31 can be set as the first light shielding member. In the second state, for example, a light shielding member different from the first light shielding member is placed between the light source unit LS and the detection unit 8 without arranging the first light shielding member of the shutter 3 on the optical path of the light from the light source unit LS. can be generated by placing it on the optical path between In the case of the present embodiment, in the second state, among the plurality of light shielding members 31 constituting the shutter 3, a light shielding member different from the light shielding member (first light shielding member) whose abnormality is to be detected is used to detect the light from the light source unit LS. can be generated by driving the shutter 3 so that it is placed on the optical path of

A method for detecting an abnormality of the light shielding member 31 of the shutter 3 in this embodiment will be described with reference to FIGS. 3 and 4. FIG. In the following, an example in which the shutter 3 is composed of the light shielding members 31A to 31C and the light shielding member 31C has an abnormality (defect or crack) will be described.

First, the correspondence relationship between the drive of the shutter 3 and the light intensity detected by the detector 8 in the exposure process will be described with reference to FIG. FIG. 3 is a diagram showing the correspondence relationship between the drive state of the shutter 3 and the detection result (light intensity) of the detector 8. As shown in FIG. State (1) in FIG. 3 shows a state in which the light blocking member 31A of the shutter 3 is arranged on the optical path. The control unit 17 causes the detection unit 8 to detect light (light intensity) in this state (1), and obtains the detection result (light intensity A01). When starting the exposure processing of the substrate (shot area), the control unit 17 moves the shutter 3 so that the light passing area 32 of the shutter 3 is arranged on the optical path, as shown in state (2) in FIG. to drive. Then, when ending the exposure process, the control unit 17 drives the shutter 3 so that the light blocking member 31B of the shutter 3 is arranged on the optical path as shown in state (3) in FIG. The control unit 17 causes the detection unit 8 to detect light in this state (3), and obtains the detection result (light intensity B01).

When starting exposure processing for the next shot area, the control unit 17 causes the shutter 3 to be positioned so that the light passing area 32 of the shutter 3 is positioned on the optical path, as shown in state (4) in FIG. drive 3; Then, when ending the exposure process, the control unit 17 drives the shutter 3 so that the light shielding member 31C of the shutter 3 is arranged on the optical path as shown in state (5) in FIG. The control unit 17 causes the detection unit 8 to detect light in this state (5), and obtains the detection result (light intensity C01). In the example shown in FIG. 3, since the light shielding member 31C has an abnormality, the light intensity C01 obtained in the state (5) is the light intensity A01 obtained in the state (1) and the light intensity A01 obtained in the state (3). It is higher than the obtained light intensity B01.

Next, a method for detecting an abnormality of the light shielding member 31C (first light shielding member) will be described with reference to FIG. FIG. 4 is a flow chart showing a method of detecting abnormality of the first light shielding member. In the following, an example will be described in which the light shielding member 31C is used as the first light shielding member and an abnormality of the light shielding member 31C is detected. In this example, state (5) of FIG. 3 may correspond to the first state, and states (1) and (3) of FIG. 3 may correspond to the second state. The abnormality detection method described below is not limited to the case where the light shielding member 31C is used as the first light shielding member. can.

In S11, the controller 17 determines whether or not it is in the first state in which the light shielding member 31C (first light shielding member) is arranged on the optical path of the light from the light source unit LS. When the light shielding member 31C is not placed on the optical path, S11 is repeated, and when the light shielding member 31C is placed on the optical path, the process proceeds to S12. In S12, the control unit 17 causes the detection unit 8 to detect light (light intensity) while the light shielding member 31C is arranged on the optical path, and stores the detection result (light intensity C01) in the memory (storage unit). .

In S13, the control unit 17 combines the detection result of the detection unit 8 obtained in S12 and the detection result of the detection unit 8 obtained in the state (second state) in which the other light blocking members 31A and 31B are arranged on the optical path. and find the difference between them. For example, as described above, the control unit 17 causes the detection unit 8 to detect light (light intensity) when the light shielding members 31A to 31B are arranged on the optical path, and the detection results (light intensity A01, light intensity B01). is stored in memory. The control unit 17 reads out the latest one of the detection results from the storage unit, and obtains the difference from the detection result of the detection unit 8 obtained in S12. Specifically, the control unit 17 controls the light intensity C01 obtained by the detection unit 8 when the light shielding member 31C is arranged on the optical path and the light intensity C01 obtained by the detection unit 8 when the light shielding member 31A is arranged on the optical path. Then, the difference (|C01-A01|) from the light intensity A01 obtained is obtained. Similarly, the control unit 17 controls the light intensity C01 obtained by the detection unit 8 when the light shielding member 31C is arranged on the optical path and the light intensity C01 obtained by the detection unit 8 when the light shielding member 31B is arranged on the optical path. A difference (|C01-B01|) from the intensity B01 is obtained.

In S14, the control unit 17 determines whether or not the difference obtained in S13 is greater than or equal to the threshold. The threshold is preferably set to a value capable of separating noise components occurring in the detection result of the detection unit 8 and individual differences of the light shielding member 31, and can be determined by experiments, simulations, or the like. If the difference obtained in S13 is less than the threshold, it is determined that there is no abnormality in the light blocking member 31C, and the process proceeds to S15. In S15, the control unit 17 determines whether or not to terminate the abnormality detection of the light shielding member 31C (first light shielding member). For example, the control unit 17 may determine that detection of the abnormality of the light shielding member 31C is finished when exposure processing is finished for each of a plurality of shot areas on the substrate. If the abnormality detection of the light blocking member 31C is to be continued, the process returns to S11.

On the other hand, in the process of S14, when the difference obtained in S13 is equal to or greater than the threshold value, it is assumed that an abnormality of the light blocking member 31C is detected, and the process proceeds to S16. In S16, the controller 17 notifies that an abnormality of the light blocking member 31C has been detected. As a method of notifying that the abnormality of the light shielding member 31C has been detected, a method of displaying the fact on a display unit (display) provided in the exposure apparatus 100 may be used, or a method of transmitting the fact to the user's computer may be used. It can be a method. In addition to or instead of detecting the abnormality of the light shielding member 31C, the control unit 17 may notify information prompting replacement of the shutter 3. FIG.

As described above, the exposure apparatus 100 of the present embodiment compares the detection results of the detection unit 8 when each of the plurality of light shielding members 31 constituting the shutter 3 is arranged on the optical path, so that each light shielding member 31 abnormalities are detected. For example, the detection result of the detection unit 8 in the first state in which the light shielding member 31C is arranged on the optical path and the detection result of the detection unit 8 in the second state in which the other light shielding members 31A and 31B are arranged on the optical path. Abnormality of the light shielding member 31C can be detected by the comparison. In other words, according to the present embodiment, it is possible to detect an abnormality of the light shielding member with high accuracy by detecting minute light leakage from the light shielding member.

<Second embodiment>
A second embodiment according to the present invention will be described. In this embodiment, the change over time of the detection result of the detection unit 8 in the first state in which the first light shielding member is arranged on the optical path, and the detection unit 8 in the second state in which the incidence of light to the detection unit 8 is blocked. The abnormality of the first light shielding member is detected by comparing the detection result of (1) with the change over time. The present embodiment basically inherits the first embodiment, and descriptions of the same elements as the first embodiment, such as the configuration of the exposure apparatus and definitions of terms, will be omitted here.

A method for detecting an abnormality of the light blocking member 31 of the shutter 3 in this embodiment will be described. The method of detecting an abnormality of the light shielding member 31 in this embodiment can be performed according to the flowchart shown in FIG. 4, but the step of S13 is different from that in the first embodiment. The step of S13, which is different from the first embodiment, will be described below.

In S13 in the present embodiment, the control unit 17 compares the change over time of the detection result of the detection unit 8 obtained in the first state with the change over time of the detection result of the detection unit 8 obtained in the second state. , find the difference between them. Specifically, the control unit 17 changes over time the detection result of the detection unit 8 obtained in the first state in which the light shielding member 31C is arranged on the optical path, and the other light shielding members 31A to 31B are arranged in the optical path. The change over time of the detection result of the detection unit 8 obtained in the second state is compared with the change over time, and the difference between them is obtained. This step will be described with reference to FIG. FIG. 5 shows the number of times each of the plurality of light shielding members 31 constituting the shutter 3 is arranged on the optical path of the light from the light source unit LS (that is, the number of light shielding times) and the detection result (light intensity) of the detection unit 8. It is a figure which shows correspondence. In FIG. 5, each of the plurality of light shielding members 31A to 31C forming the shutter 3 is shielded 11 times, and the light intensity detected by the detector 8 during each light shielding is shown.

For example, with respect to the light shielding member 31C, the control unit 17 determines the light intensity C11 detected by the detection unit 8 at the current (11th) light shielding and the light intensity C10 detected by the detection unit 8 at the previous (10th) light shielding. change ΔC (=C11-C10). In addition, the control unit 17 calculates changes ΔA (=A11−A10) and ΔB (=B11−B10) in light intensity between this time (11th time) and the previous time (10th time) for each of the light shielding members 31A to 31B. Obtained as change over time. Then, the control unit 17 obtains the difference between the obtained changes between the light shielding members. Specifically, the control unit 17 obtains the difference (|ΔC−ΔA|) between the change ΔC for the light shielding member 31C and the change ΔA for the light shielding member 31A. Similarly, the control unit 17 obtains the difference (|ΔC−ΔB|) between the change ΔC for the light shielding member 31C and the change ΔB for the light shielding member 31B.

As described above, in the present embodiment, for each of the plurality of light shielding members 31 constituting the shutter 3, the abnormality of each light shielding member 31 is detected by comparing the change over time of the detection result of the detection unit 8 when the light is shielded. . According to the present embodiment, similarly to the first embodiment, it is possible to detect an abnormality of the light shielding member with high accuracy by detecting minute light leakage from the light shielding member.

<Third Embodiment>
A third embodiment according to the present invention will be described. In the first and second embodiments, the second state in which light is blocked from entering the detection unit 8 is obtained by using a light shielding member different from the first light shielding member among the plurality of light shielding members 31 constituting the shutter 3. I explained how to generate it. In this embodiment, a method of generating the second state using a second light blocking member that is provided apart from the shutter 3 and blocks light from the light source section LS will be described. Here, the present embodiment basically inherits the first and second embodiments, and the basic configuration of the exposure apparatus and definitions of terms, etc., which are the same as those of the first and second embodiments, will be described here. is omitted.

FIG. 6 is a diagram showing the configuration of the exposure apparatus of this embodiment. In this embodiment, a second light blocking member 50 that can be inserted into the optical path between the light source unit LS and the detection unit 8 is provided. The second light shielding member 50 is, for example, a member that blocks light from the light source unit LS, and in the example shown in FIG. be. The control unit 17 inserts the second light shielding member 50 into the optical path to generate a second state in which light is blocked from entering the detection unit 8, and displays the detection result (light strength) is acquired in advance and stored in a memory (storage unit).

A method for detecting an abnormality of the light blocking member 31 of the shutter 3 in this embodiment will be described. The method of detecting an abnormality of the light shielding member 31 in this embodiment can be performed according to the flowchart shown in FIG. In S13 in the present embodiment, the control unit 17 combines the detection result of the detection unit 8 obtained in S12 with the detection unit obtained in advance with the second light shielding member 50 inserted into the optical path (second state). 8 and the difference between them is calculated.

As described above, in this embodiment, the detection result of the detection unit 8 in the first state in which the first light shielding member of the shutter 3 is arranged on the optical path and the detection result in the second state in which the second light shielding member 50 is inserted on the optical path The abnormality of the first light shielding member is detected by comparing the detection result of the detection unit 8 with the detection result of the first light shielding member. As the first light shielding member, each of the plurality of light shielding members 31 forming the shutter 3 can be applied. Also according to the present embodiment, as in the first and second embodiments, it is possible to detect an abnormality of the light shielding member with high accuracy by detecting minute light leakage from the light shielding member.

Here, in the present embodiment, by inserting the second light shielding member 50 into the optical path, the second state in which light is blocked from entering the detection unit 8 is generated, but the present invention is not limited to this. For example, without using the second light shielding member 50, the second state may be generated by turning off the light source unit LS (light source 1). Also in this case, the control unit 17 preferably obtains in advance the detection result (light intensity) of the detection unit 8 in the second state and stores it in the memory (storage unit).

<Fourth Embodiment>
A fourth embodiment according to the present invention will be described. In the present embodiment, a method of controlling driving of the shutter 3 when an abnormality of the first light shielding member is detected will be described. This embodiment basically inherits the first to third embodiments, and descriptions of the same elements as those in the first to third embodiments, such as the configuration of the exposure apparatus and definitions of terms, are omitted here. do.

When an abnormality is detected in the first light shielding member (for example, the light shielding member 31C) among the plurality of light shielding members 31, the exposure apparatus (control unit 17) of the present embodiment detects the light shielding members other than the first light shielding member (for example, the light shielding member 31C). The driving of the shutter 3 is controlled so as to block light using the members 31A and 31B). In other words, when an abnormal light shielding member is detected among the plurality of light shielding members 31 forming the shutter 3, the exposure apparatus of the present embodiment does not use the abnormal light shielding member and uses the remaining light shielding members. to continue exposure processing of the substrate. The exposure processing of the substrate in this embodiment will be described below with reference to FIG. FIG. 7 is a flowchart showing substrate exposure processing in this embodiment.

In S<b>21 , the control unit 17 determines whether or not there is a light shielding member 31 for which an abnormality has been detected among the plurality of light shielding members 31 forming the shutter 3 . Hereinafter, the light shielding member 31 for which an abnormality has been detected may be referred to as an "abnormal light shielding member". If there is an abnormal light shielding member, the process proceeds to S22, and if there is no abnormal light shielding member, the process proceeds to S24. In S22, the control unit 17 determines whether or not the light shielding member 31 scheduled to be used for the next light shielding (the next light shielding member 31) is an abnormal light shielding member. If the next light shielding member 31 is an abnormal light shielding member, the process proceeds to S23, and if the next light shielding member 31 is not an abnormal light shielding member, the process proceeds to S24.

In S<b>23 , the control unit 17 changes the setting of the rotation direction of the shutter 3 . For example, the control unit 17 changes the rotation direction setting of the shutter 3 to a rotation direction opposite to the previous rotation direction. By this process, the exposure processing of the substrate can be continued using the remaining light shielding members excluding the abnormal light shielding members without using the abnormal light shielding members among the plurality of light shielding members 31 constituting the shutter 3 .

In S24, the control unit 17 performs exposure processing on a target shot area (target shot area) to be exposed among the plurality of shot areas on the substrate. Specifically, the control unit 17 rotates the shutter 3 to allow the light from the light source unit LS to pass through the light passage area 32, and then rotates the shutter 3 so that the exposure amount of the substrate reaches the target exposure amount. The light from the light source section LS is blocked by the light blocking member 31 which is rotationally driven. At this time, if the setting of the rotation direction of the shutter 3 has been changed in S23, the control unit 17 rotates the shutter 3 in the changed rotation direction so that the light from the light source unit LS does not pass through. block and control.

In S<b>25 , the control unit 17 detects an abnormality of the light shielding member currently arranged on the optical path of the light from the light source unit LS among the plurality of light shielding members 31 forming the shutter 3 . Specifically, assuming that the light shielding member currently arranged on the optical path is the first light shielding member, the control unit 17 causes the detection unit 8 to emit light ( light intensity) is detected. Then, the control unit 17 compares the detection result of the detection unit 8 in the first state with the detection result of the detection unit 8 in the second state in which the incidence of light to the detection unit 8 is blocked, thereby An abnormality of the first light shielding member is detected. The detection of abnormality of the first light shielding member in this step can be performed according to the flowchart shown in FIG. 4, for example.

In S26, the control unit 17 determines whether or not exposure processing has been performed on all of the plurality of shot areas on the substrate. If there is a shot area that has not been subjected to exposure processing, the process returns to S21, sets the shot area that has not been subjected to exposure processing as the target shot area, and performs exposure processing. On the other hand, if exposure processing has been performed for all shot areas, the process ends.

Next, an example of rotational driving of the shutter 3 in this embodiment will be described with reference to FIG. FIG. 8 is a diagram showing an example of rotational driving of the shutter 3. As shown in FIG. FIG. 8 shows an example in which the light shielding member 31C among the plurality of light shielding members 31 forming the shutter 3 is damaged (cracked) and identified as an abnormal light shielding member.

In the state (1), it is determined in the process of S25 that the light shielding member 31C is abnormal (cracked) (that is, the light shielding member 31C is identified as an abnormal light shielding member). Further, since the light shielding member 31A, which is scheduled to be used for light shielding after the light shielding member 31C, is not an abnormal light shielding member, it is determined as "No" in the process of S22, and the process proceeds to S24 to show the state (2)→(3). , the exposure process is performed by driving the shutter 3 to rotate in the rotation direction thus far. In addition, since the light shielding member B, which is scheduled to be used for light shielding after the light shielding member 31A, is not an abnormal light shielding member, it is judged as "No" in the step of S22, and the process proceeds to S24 to show the state (4)→(5). , the exposure process is performed by driving the shutter 3 to rotate in the rotation direction thus far.

On the other hand, the light shielding member 31C, which is scheduled to be used for light shielding after the light shielding member 31B, is specified as an abnormal light shielding member. Orientation is set. Then, as shown in states (6)→(3), the shutter 3 is rotationally driven in the reverse set rotation direction to perform the exposure process, and the light shielding member 31A shields the light at the end of the exposure process. Further, in the rotation direction of the shutter 3 after the change, the light shielding member 31C specified as the abnormal light shielding member is scheduled to be used next to the light shielding member A for light shielding. Therefore, in the process of S22, it is judged as "Yes", and the process proceeds to S23, and the rotational direction of the shutter 3 is set to be reversed again (that is, the rotational direction of the shutter 3 is returned to its original direction). Then, as shown in states (4)→(5), the shutter 3 is rotationally driven again in the opposite rotational direction to perform the exposure process, and the light shielding member 31B shields the light when the exposure process ends.

As described above, in the present embodiment, when the light shielding member 31C is identified as an abnormal light shielding member, the rotational driving of the shutter 3 is controlled so that the light shielding members 31A and 31B are alternately used to shield light. As a result, the exposure process can be continued using the remaining light shielding members 31A and 31B except for the light shielding member 31C, so that the exposure amount of the substrate can be controlled with high precision, which is advantageous in terms of throughput. sell.

<Fifth Embodiment>
A fifth embodiment according to the present invention will be described. In the present embodiment, a method of controlling driving of the shutter 3 when an abnormality of the first light shielding member is detected will be described. This embodiment basically inherits the first to fourth embodiments, and descriptions of the same elements as those in the first to fourth embodiments, such as the configuration of the exposure apparatus and definitions of terms, are omitted here. do.

Even if an abnormality is detected in the light shielding member 31 of the shutter 3, the influence of light leaking from the light shielding member 31 on the exposure process may be small depending on the target exposure amount set in the exposure process. For example, if the target exposure amount set in the exposure process is much larger than the exposure amount that can be increased by leaked light, an abnormal light shielding member is used as the light shielding member used for shielding light in the exposure process. be able to. However, as described above, the exposure amount of the substrate is defined by the time integral of the illuminance of the light with which the substrate is irradiated. That is, the longer the light shielding member having an abnormality blocks the light, the more the exposure energy due to the leaked light can be accumulated (that is, the greater the increase in the exposure amount due to the leaked light). In this case, overexposure may occur in the exposure process, making it difficult to accurately form a pattern on the substrate.

In particular, among a plurality of shot areas on the substrate, the shot area that is subjected to the last exposure process (hereinafter referred to as the last shot area) has a longer exposure time to the leaked light after the exposure process than the other shot areas. can be long, so the overexposure mentioned above can be significant. For example, in the last shot area, after the exposure process, preparations such as loading and unloading of the substrate and exchange of the original for changing the exposure pattern can be performed. Therefore, it takes time to move the last shot area from the position where the exposure process was performed, and the time of exposure to leaked light after the exposure process can be longer than other shot areas.

Therefore, in the exposure apparatus (control unit 17) of the present embodiment, the light shielding members used at the end of the exposure processing for the last shot area are the remaining light shielding members 31 of the plurality of light shielding members 31 constituting the shutter 3, excluding the abnormal light shielding member. Rotational drive of the shutter is controlled so as to act as a light shielding member. For example, as shown in FIG. 9, among the plurality of shot regions 110 to 116 on the substrate, the light shielding member scheduled to be used when the exposure processing for the last shot region 116 ends is the light shielding member specified as the abnormal light shielding member. 31C. In this case, as in the example shown in FIG. 10, the control unit 17 determines that the light shielding member 31B (or the light shielding member 31A) different from the light shielding member 31C is used when the exposure processing for the last shot region 116 is completed. ), the rotational drive of the shutter 3 is controlled. The exposure processing of the substrate in this embodiment will be described below with reference to FIG. FIG. 11 is a flowchart showing substrate exposure processing in this embodiment.

In S<b>31 , the control unit 17 determines whether or not there is a light shielding member 31 for which an abnormality has been detected (abnormal light shielding member) among the plurality of light shielding members 31 forming the shutter 3 . If there is an abnormal light shielding member, the process proceeds to S32, and if there is no abnormal light shielding member, the process proceeds to S35. In S32, the control unit 17 determines whether the shot area (next shot area) to be exposed next is the last shot area. If the next shot area is the last shot area, the process proceeds to S33, and if the next shot area is not the last shot area, the process proceeds to S35. In S33, the control unit 17 determines whether or not the light shielding member 31 scheduled to be used at the end of the exposure process for the last shot area (light shielding member 31 scheduled to be used last) is an abnormal light shielding member. When the last light shielding member 31 to be used is an abnormal light shielding member, the process proceeds to S34, and when the last light shielding member 31 to be used is not an abnormal light shielding member, the process proceeds to S35.

In S<b>34 , the control unit 17 changes the setting of the rotation direction of the shutter 3 . For example, the control unit 17 changes the rotation direction setting of the shutter 3 to a rotation direction opposite to the previous rotation direction. By this process, the rotational drive of the shutter 3 can be controlled so that the remaining light shielding members excluding the abnormal light shielding member are used for light shielding at the end of the last shot area.

S35 to S37 are the same steps as S24 to S26 in the flow chart shown in FIG. Specifically, in S<b>35 , the control unit 17 performs exposure processing on a shot area to be exposed (target shot area) among the plurality of shot areas on the substrate. In S<b>36 , the control unit 17 detects an abnormality of the light shielding member currently arranged on the optical path of the light from the light source unit LS among the plurality of light shielding members 31 forming the shutter 3 . The detection of abnormality of the first light shielding member in this step can be performed according to the flowchart shown in FIG. 4, for example. Further, in S37, the control unit 17 determines whether or not exposure processing has been performed on all of the plurality of shot areas on the substrate. If there is a shot area that has not been subjected to exposure processing, the process returns to S31, sets the shot area that has not been subjected to exposure processing as the target shot area, and performs exposure processing. On the other hand, if exposure processing has been performed for all shot areas, the process ends.

As described above, in the present embodiment, the rotational drive of the shutter 3 is controlled so that the remaining light shielding members excluding the abnormal light shielding member are used when the exposure processing for the last shot area is completed. As a result, in the last shot area, the influence of leaked light from the abnormal light shielding member can be reduced, and the exposure amount can be controlled with high accuracy.

<Sixth embodiment>
A sixth embodiment according to the present invention will be described. In the above-described fifth embodiment, it is determined whether or not the last light shielding member to be used is an abnormal light shielding member immediately before the exposure processing for the last shot area is performed, and the rotation of the shutter 3 is driven according to the determination result. An example of controlling has been described. However, the present invention is not limited to this, and when it can be grasped in advance that the light shielding member to be used last will be an abnormal light shielding member, the rotational driving of the shutter 3 may be controlled at the time of the grasping. In the present embodiment, an example of controlling the rotational drive of the shutter 3 when it is determined in advance that the light shielding member to be used last will be the abnormal light shielding member will be described with reference to FIG. 12 . FIG. 12 is a flowchart showing substrate exposure processing in this embodiment.

In S<b>41 , the control unit 17 determines whether or not there is a light shielding member 31 for which an abnormality has been detected (abnormal light shielding member) among the plurality of light shielding members 31 forming the shutter 3 . If there is an abnormal light shielding member, the process proceeds to S42, and if there is no abnormal light shielding member, the process proceeds to S44. In S42, the control unit 17 determines whether or not the light shielding member 31 to be used last becomes an abnormal light shielding member when the exposure processing for each shot area is continued while the shutter 3 is rotationally driven. When the last light shielding member 31 to be used becomes an abnormal light shielding member, the process proceeds to S43, and when the last light shielding member 31 to be used does not become an abnormal light shielding member, the process proceeds to S44.

In S<b>43 , the control unit 17 changes the setting of the rotation direction of the shutter 3 . For example, the control unit 17 changes the rotation direction setting of the shutter 3 to a rotation direction opposite to the previous rotation direction. By this process, the rotational drive of the shutter 3 can be controlled so that the remaining light shielding members excluding the abnormal light shielding member are used for light shielding at the end of the last shot area.

S44 to S46 are the same steps as S24 to S26 in the flow chart shown in FIG. Specifically, in S<b>44 , the control unit 17 performs exposure processing on a shot area to be exposed (target shot area) among the plurality of shot areas on the substrate. In S<b>45 , the control unit 17 detects an abnormality of the light shielding member currently arranged on the optical path of the light from the light source unit LS among the plurality of light shielding members 31 forming the shutter 3 . The detection of abnormality of the first light shielding member in this step can be performed according to the flowchart shown in FIG. 4, for example. Also, in S46, the control unit 17 determines whether or not the exposure processing has been performed on all of the plurality of shot areas on the substrate. If there is a shot area that has not been subjected to exposure processing, the process returns to S41, sets the shot area that has not been subjected to exposure processing as the target shot area, and performs exposure processing. On the other hand, if exposure processing has been performed for all shot areas, the process ends.

As described above, in the present embodiment, the rotational drive of the shutter 3 is controlled so that the remaining light shielding members excluding the abnormal light shielding member are used when the exposure processing for the last shot area is completed. As a result, similarly to the fifth embodiment, in the last shot area, the influence of leaked light from the abnormal light shielding member can be reduced, and the exposure amount can be controlled with high precision.

<Embodiment of method for manufacturing article>
The method for manufacturing an article according to the embodiment of the present invention is suitable for manufacturing an article such as a microdevice such as a semiconductor device or an element having a fine structure. The method for manufacturing an article according to the present embodiment includes a step of forming a latent image pattern on a photosensitive agent applied to a substrate using the exposure apparatus (the step of exposing the substrate), and a step of forming the latent image pattern in this step. and developing (processing) the substrate. In addition, such manufacturing methods include other well-known steps (oxidation, deposition, deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The article manufacturing method of the present embodiment is advantageous in at least one of article performance, quality, productivity, and production cost compared to conventional methods.

The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the claims are appended to make public the scope of the invention.

1: light source, 3: shutter, 31: light shielding member, 32: light passing area, 8: detection unit, 17: control unit, 50: second light shielding member, 100: exposure device

Claims (10)

An exposure apparatus for exposing a substrate,
a shutter having a first light blocking member that blocks light from a light source;
a detection unit that detects the light that has passed through the shutter;
a control unit that controls exposure processing of the substrate by driving the shutter;
including
The control unit controls the detection result of the detection unit in a first state in which the first light shielding member is arranged in the optical path of the light, and the detection unit in the state in which the first light shielding member is not arranged in the optical path of the light. and detecting an abnormality of the first light shielding member by comparing the detection result of the detection unit in a second state in which the light is blocked from entering the exposure apparatus. The shutter has a plurality of light shielding members including the first light shielding member, and is configured to allow the light to pass through a light passage region between the plurality of light shielding members,
The control unit controls driving of the shutter so that, in the second state, a light shielding member different from the first light shielding member among the plurality of light shielding members is arranged in the optical path of the light. 2. The exposure apparatus according to claim 1, wherein: The control unit detects an abnormality of the first light shielding member by comparing the change over time of the detection result of the detection unit in the first state with the change over time of the detection result of the detection unit in the second state. 3. The exposure apparatus according to claim 2, wherein the detection is performed. further comprising a second light shielding member spaced apart from the shutter and shielding the light;
2. An exposure apparatus according to claim 1 , wherein said control section inserts said second light blocking member into an optical path between said light source and said detection section in said second state. 2. The exposure apparatus according to claim 1 , wherein said control section turns off said light source in said second state. The shutter has a plurality of light shielding members including the first light shielding member, and is configured to allow the light to pass through a light passage region between the plurality of light shielding members,
The controller drives the shutter so as to block the light using the remaining light shielding members of the plurality of light shielding members excluding the first light shielding member when an abnormality of the first light shielding member is detected. 6. The exposure apparatus according to any one of claims 1 to 5, wherein the exposure apparatus controls The shutter has a plurality of light shielding members including the first light shielding member, and is configured to allow light to pass through a light passage region between the plurality of light shielding members,
the substrate includes a plurality of shot areas where the exposure processing is performed, respectively;
When the controller detects an abnormality of the first light shielding member, the light shielding member used at the end of the exposure process for the last shot area among the plurality of shot areas is the first light shielding member among the plurality of light shielding members. 7. The exposure apparatus according to any one of claims 1 to 6, wherein driving of said shutter is controlled so that the remaining light shielding members except for one light shielding member. The shutter is configured to switch between blocking of the light by each light shielding member and passage of the light by the light passing region by rotating,
8. The exposure apparatus according to claim 6, wherein the control section changes the rotation direction of the shutter as the drive control of the shutter when an abnormality of the first light shielding member is detected. 9. The exposure apparatus according to any one of claims 1 to 8, wherein when detecting an abnormality of the first light shielding member, the control section notifies the abnormality. an exposure step of exposing a substrate using the exposure apparatus according to any one of claims 1 to 9;
and a processing step of processing the substrate exposed in the exposure step,
A method for manufacturing an article, comprising manufacturing an article from the substrate processed in the processing step.

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