JP7699031B2 - SUBSTRATE PROCESSING APPARATUS, SUBSTRATE PROCESSING METHOD, AND STORAGE MEDIUM - Google Patents

Description

The present disclosure relates to a substrate processing apparatus, a substrate processing method, and a storage medium.

Patent Document 1 discloses an auxiliary exposure device that irradiates a resist film formed on a substrate with ultraviolet light separately from the exposure process, thereby improving the precision or in-plane uniformity of the film thickness or line width of the resist pattern.

JP 2013-186191 A

This disclosure provides a technology that can make the sensitivity during exposure processing uniform across a substrate that uses a resist material suitable for EUV lithography.

A substrate processing apparatus according to one aspect of the present disclosure includes a substrate support section configured to support, while rotating, a substrate on which a resist film made of a resist material for EUV lithography has been formed; a light source that irradiates irradiation light including vacuum ultraviolet light; a shutter that switches between a state in which the irradiation light reaches the substrate and a state in which it does not reach the substrate by moving between an area on the optical path of the irradiation light and an area other than the optical path; a light-transmitting plate that transmits the irradiation light; a light-shielding plate that limits the irradiation range of the irradiation light that reaches the substrate by allowing the irradiation light to pass only through an opening portion; and a shielding section that can be positioned to block the irradiation light irradiated to the center of rotation of the substrate that is supported and rotated by the substrate support section, and the irradiation light is irradiated to a radially continuous area that is a portion of the surface of the substrate.

This disclosure provides a technology that can make the sensitivity during exposure processing uniform across a substrate that uses a resist material suitable for EUV lithography.

FIG. 1 is a diagram illustrating a substrate processing apparatus according to an exemplary embodiment. FIG. 2 is a diagram illustrating the light shielding plate. FIG. 3 is a diagram for explaining the opening portion of the light blocking plate. FIG. 4 is a diagram illustrating the arrangement of the illuminometers. FIG. 5 is a block diagram illustrating an example of a hardware configuration of the controller. FIG. 6 is a graph showing the dose amount for each region in the workpiece. FIG. 7 is a diagram illustrating the operation of the lid portion. FIG. 8 is a flow chart illustrating an example of a substrate processing method. FIG. 9 is a diagram illustrating an operation sequence related to irradiation of VUV light. FIG. 10 is a diagram illustrating a shielding portion according to a modified example. FIG. 11 is a diagram illustrating a light irradiation mechanism according to a modified example. FIG. 12 is a diagram illustrating a light irradiation mechanism according to a modified example. FIG. 13 is a diagram illustrating a light irradiation mechanism according to a modified example.

The following describes the embodiments in detail with reference to the drawings. In the description, the same elements or elements having the same functions are given the same reference numerals, and duplicate descriptions are omitted.

[Configuration of the Substrate Processing Apparatus]
FIG. 1 is a schematic diagram (longitudinal side view) showing a first configuration example of the substrate processing apparatus of this embodiment. The substrate processing apparatus 1 shown in FIG. 1 irradiates processing light onto a workpiece W. For example, the substrate processing apparatus 1 is configured to irradiate light including vacuum ultraviolet light (VUV light: Vacuum Ultra Violet Light) onto a resist film or resist pattern formed on the surface of the workpiece W. The irradiation of light including vacuum ultraviolet light by the substrate processing apparatus 1 can improve the sensitivity of these resist films during exposure. In addition, the irradiation of light including vacuum ultraviolet light can also improve the roughness of the surface of the resist pattern obtained by the exposure and development process.

The workpiece W to be processed is, for example, a substrate, or a substrate on which a film and a circuit, etc. have been formed by performing a specified process. The substrate included in the workpiece W is, for example, a wafer containing silicon. The workpiece W (substrate) is, for example, disk-shaped, but may have a part of the circle cut out or may have a shape other than a circle, such as a polygon. The workpiece W to be processed may be a glass substrate, a mask substrate, an FPD (Flat Panel Display), etc., or may be an intermediate product obtained by performing a specified process on such a substrate, etc.

The substrate processing apparatus 1 has a function of irradiating the surface of the workpiece W with processing irradiation light L1. As an example, a resist film is formed on a silicon-on-carbon (SOC) film on a substrate and a silicon-on-glass (SOG) film on the SOC film, and then a resist pattern of a predetermined pattern is formed by performing exposure and development processing. The resist pattern is a mask pattern for etching the SOC film and SOG film, which are the underlayer films, to form a pattern in these underlayer films. The substrate processing apparatus 1 has a function of improving the roughness of the surface of the resist pattern, for example, by irradiating the surface of the workpiece W on which the resist pattern is formed with processing irradiation light L1. In this embodiment, a case will be described in which the substrate processing apparatus 1 irradiates the workpiece W with processing irradiation light L1 after the resist film is formed and before the exposure and development processing is performed.

In the substrate processing apparatus 1 according to this embodiment, the resist material used to form the resist pattern is a material suitable for EUV lithography using an EUV laser as the exposure light source. An EUV laser (Extreme Ultraviolet) is a laser with a wavelength of 13.5 nm. The substrate processing apparatus 1 is used to irradiate the workpiece W on which a resist film made of a resist material has been formed with light containing the above-mentioned VUV light under specified conditions. As a result, the sensitivity in the subsequent exposure process is improved. Furthermore, the roughness of the resist surface when the resist pattern is formed by the exposure and development process is improved. The roughness of the surface of the pattern resulting from etching using this resist pattern as a mask can also be improved.

The following describes each part of the substrate processing apparatus 1. As shown in FIG. 1, the substrate processing apparatus 1 includes a processing chamber 20, a light irradiation mechanism 40 (light source), a light amount adjustment mechanism 50, a measurement unit 60, and a controller 100 (control unit).

The processing chamber 20 includes a housing 21, a transfer port 22, a rotation support section 25 (substrate support section), a gas supply section 30, a gas exhaust section 32, and an atmosphere adjustment section 34. The housing 21 is, for example, part of a vacuum container provided in an atmospheric atmosphere, and is configured to be able to store a workpiece W transferred by a transfer mechanism (not shown). In other words, the housing 21 functions as a processing container for performing processing related to the workpiece W inside.

In the substrate processing apparatus 1, processing is performed on the workpiece W while the workpiece W is stored in the housing 21. A transfer port 22 is formed in the side wall of the housing 21. The transfer port 22 is an opening for loading and unloading the workpiece W into and from the housing 21. The transfer port 22 is opened and closed by a gate valve 23.

The rotation support unit 25 is configured to be able to support the workpiece W while rotating it based on instructions from the controller 100 in the housing 21. The rotation support unit 25 has, for example, a holding unit 26 and a rotation drive unit 27. The holding unit 26 supports the center portion of the workpiece W arranged horizontally with the surface on which the resist pattern is formed facing up, and holds the workpiece W, for example, by vacuum suction or the like (holding it by the pressure difference with the pressure of the chamber). This allows the workpiece W to be rotated at high speed. The rotation drive unit 27 has a function of rotating the holding unit 26 holding the workpiece W together with the workpiece W around a vertical axis. The rotation drive unit 27 is, for example, a rotation actuator powered by an electric motor. The rotation drive unit 27 has its rotation axis provided at the rotation center A1 of the workpiece W.

The gas supply unit 30 is configured to supply an inert gas (e.g., argon, nitrogen, etc.) into the housing 21 through a through hole 21a formed in the housing 21. The gas supply unit 30 has a gas source 30a, a valve 30b, and a pipe 30c. The gas source 30a stores an inert gas and functions as a supply source of the inert gas. The valve 30b operates based on an operation signal from the controller 100 to open and close the pipe 30c. The pipe 30c connects the gas source 30a, the valve 30b, and the through hole 21a in this order from the upstream side.

The gas exhaust unit 32 exhausts gas from the housing 21 through a through hole 21b formed in the housing 21. The gas exhaust unit 32 has a vacuum pump 32a and a pipe 32c. The vacuum pump 32a exhausts gas from inside the housing 21. The pipe 32c connects the through hole 21b and the vacuum pump 32a.

The atmosphere adjustment unit 34 can adjust the atmosphere inside the housing 21 to the atmospheric atmosphere through a through hole 21c formed in the housing 21. The atmosphere adjustment unit 34 has a valve 34b and a pipe 34c. The valve 34b operates based on an operation signal from the controller 100 to open and close the pipe 34c. The pipe 34c can connect the through hole 21c to the atmospheric atmosphere. In other words, when the valve 34b is opened, the atmosphere inside the housing 21 is adjusted to the atmospheric atmosphere.

The light irradiation mechanism 40 has a light source unit 42 that irradiates irradiation light including vacuum ultraviolet light. The light source unit 42 may be housed in a housing (not shown) provided on the upper part of the housing 21. The light source unit 42 may be turned on and off by a switch (not shown) controlled by the controller 100, for example. In the substrate processing apparatus 1, the irradiation position of the light source unit 42 is configured to be divided into a part of the workpiece W rather than the entire workpiece W, assuming that the workpiece W is rotated by the rotation support unit 25. Specifically, the optical axis center A2 of the light source unit 42 is offset outward along the radial direction of the workpiece W with respect to the rotation center A1 of the workpiece W. In the example shown in FIG. 1, the optical axis center A2 is offset to such an extent that the irradiation light L1 from the light source unit 42 can irradiate one end of the workpiece W (the right end in FIG. 1) while irradiating the vicinity of the center of the workpiece W. In this case, the irradiation light L1 from the light source unit 42 is not irradiated to the entire surface of the workpiece W, so that the distance between the light source unit 42 and the workpiece W can be reduced.

The lamp in the light source unit 42 irradiates light including light in the wavelength range of 115 nm to 400 nm, for example. The lamp is, for example, always on for the stability of the light source. As an example, the light source unit 42 irradiates light having a continuous spectrum of 115 nm to 400 nm. "Light having a continuous spectrum" may include light including continuous spectral components in at least a portion of a band (e.g., a wavelength width of 10 nm or more) included in the wavelength range of 100 nm to 200 nm (corresponding to the wavelength range of vacuum ultraviolet light (VUV light)).

The continuous spectrum refers to a spectrum that spreads continuously in a specific wavelength range (in this embodiment, a wavelength width of 10 nm or more), and is a spectrum that is distinguished from a line spectrum (bright line spectrum) at a specific wavelength. As light that forms a continuous spectrum including a part of the wavelength range of 100 nm to 200 nm, light that forms a continuous spectrum in the above-mentioned wavelength range of 115 nm to 400 nm may be used. Note that the light emitted from the light source unit 42 does not need to be "light that forms a continuous spectrum" in the entire wavelength range, but is light that forms a continuous spectrum in at least a part of the range. As an example, the light emitted from the light source unit 42 forms a continuous spectrum in a wavelength range that overlaps with the wavelength range of 100 nm to 200 nm (corresponding to the wavelength range of vacuum ultraviolet light (VUV light)), and the effect of the light irradiated from the light source unit 42 described below is effectively exerted.

Vacuum ultraviolet light (VUV light) generally has a wavelength in the range of 10 nm to 200 nm. However, the effect of processing by the substrate processing apparatus 1, i.e., the effect of modifying the resist film, can be improved more when the light emitted from the light source unit 42 is VUV light with a long wavelength of 100 nm or more. Light on the short wavelength side (light with a wavelength shorter than 100 nm) does not easily penetrate into the resist film, so it may be difficult to achieve a modifying effect on the entire resist film.

The main wavelength range of the light irradiated from the light source unit 42 may be different from the wavelength of the light used for exposure of the resist film, for example. The wavelength of the light used for exposure is, for example, an EUV laser (Extreme Ultraviolet) which is a laser with a wavelength of 13.5 nm. When light of the wavelength used for exposure of the resist film, i.e., EUV light, is used in the substrate processing apparatus 1, there is a possibility that the exposure process of the workpiece W will proceed at the timing of processing by the substrate processing apparatus 1. Therefore, it is considered that by setting the main wavelength range of the light emitted from the light source unit 42 to 100 nm or more, the effect of light of a wavelength different from exposure by EUV light can be obtained.

The light emitted from the light source unit 42 may contain near-ultraviolet light (near ultraviolet light) having a longer wavelength than VUV light, in addition to VUV light. As an example, the light from the light source unit 42 may be configured to contain light in a wavelength band of 160 nm or less. In this way, the light emitted from the light source unit 42 contains at least light in the wavelength range defined as VUV light.

The lamp provided in the light source unit 42 may be, for example, a deuterium lamp, and may be configured to irradiate VUV light with a wavelength of 200 nm or less. The wavelength of the peak of the continuous spectrum may be, for example, 160 nm or less, or 150 nm or more. In addition, the light from the light source unit 42 has a peak wavelength in the optical spectrum of 248 nm or less, thereby enhancing the effect of the light in the wavelength range of VUV light contained in the light from the light source unit 42. The light from the light source unit 42 may be light that forms a continuous spectrum with multiple sub-peaks. The sub-peaks may be 248 nm or less, for example, 160 nm or less. Note that the light from the light source unit 42 is not limited to a continuous spectrum, and may include light of one or more wavelengths in the wavelength range of 115 nm to 400 nm, for example.

Because the wavelength range of the spectrum of the light irradiated from the light source unit 42 is relatively wide, the resist film on the workpiece W receives the energy of light of various wavelengths. As a result, various reactions occur on the surface of the resist film. Specifically, the sensitivity of the resist film to exposure is increased by breaking chemical bonds at various positions in the molecules that make up the resist film. Therefore, exposure is performed appropriately even with a smaller amount of exposure. In addition, since various compounds are generated by breaking the above-mentioned chemical bonds, the orientation of the molecules that existed in the resist film before the light irradiation is eliminated. As a result, the surface free energy of the resist film is reduced and the internal stress is reduced. In other words, by using the light source unit 42 as a light source, the fluidity of the surface of the resist film is easily increased, and as a result, the effect of improving the roughness of the surface when the resist pattern is formed can be improved.

When irradiating light including VUV light from the light source unit 42, if there is a bias in the light energy received by the resist film on the workpiece W, there is a possibility that a bias in the resist characteristics will occur on the surface of the workpiece W irradiated with VUV light. Therefore, it is required that the light including VUV light is irradiated as evenly as possible over the entire surface of the workpiece W. Also, when adjusting the characteristics of the resist film on the surface of the workpiece W by irradiating light from the light source unit 42, the amount of light irradiation may be important. Therefore, in the substrate processing apparatus 1, the amount of light is adjusted using the light amount adjustment mechanism 50.

As described above, the light amount adjustment mechanism 50 has a function of adjusting the amount of the irradiation light L1 on the optical path of the irradiation light L1 emitted from the light source unit 42. In the example shown in FIG. 1, the light amount adjustment mechanism 50 includes a lamp shutter 51, a rotation center shutter 52 (shielding unit), a light-transmitting plate 53, and a light-shielding plate 54.

The lamp shutter 51 has a function of switching between a state in which the irradiated light L1 from the light source unit 42 reaches the workpiece W and a state in which it does not reach the workpiece W. The lamp shutter 51 has, for example, a shielding plate 51a (shutter) that can be placed on the optical path of the irradiated light L1, and a support part 51b that supports the shielding plate 51a movably (openable and closable). The shielding plate 51a is sized to be able to block all of the irradiated light L1 from the light source unit 42. In addition, the support part 51b movably supports the shielding plate 51a between the optical path and an area other than the optical path, for example, with the shielding plate 51a perpendicular to the optical axis of the irradiated light L1. By moving the shielding plate 51a with the support part 51b, it is possible to switch between a state in which the irradiated light L1 from the light source unit 42 reaches the workpiece W and a state in which it does not reach the workpiece W. That is, the shielding plate 51a moves between the optical path of the irradiated light L1 and an area other than the optical path, thereby switching between a state in which the irradiated light L1 reaches the workpiece W and a state in which it does not reach the workpiece W. The movement of the shielding plate 51a is controlled by, for example, the controller 100. Note that FIG. 1 shows a state in which the shielding plate 51a is disposed on the optical path.

The light-transmitting plate 53 is provided below the lamp shutter 51 (on the side farther from the light source unit 42) and also functions as a so-called partition wall that transmits the irradiation light L1. That is, the light-transmitting plate 53 is arranged so as to divide the space inside the housing 21 into the light source unit 42 side and the work W side. As a result, the space below the light-transmitting plate 53 becomes a closed space independent of the space above. When the gas supply unit 30, the gas exhaust unit 32, and the atmosphere adjustment unit 34 are arranged below the light-transmitting plate 53, the atmosphere in the space below the light-transmitting plate 53 where the work W exists can be appropriately adjusted. The light-transmitting plate 53 may be, for example, glass (for example, magnesium fluoride glass). Note that the entire light-transmitting plate 53 does not need to be substantially 100% transparent to the irradiation light L1, as long as at least the optical path of the irradiation light L1 can transmit the irradiation light L1.

The rotation center shutter 52 is a shielding part configured to be able to transition between a first state in which the part of the irradiation light L1 irradiated to the rotation center A1 of the workpiece W that is supported by the holding part 26 of the rotation support part 25 and rotates, and a second state that is a state other than the first state. The rotation center shutter 52 has, for example, a cover part 52a configured to be arranged so as to cover the rotation center A1 of the workpiece W, and a support part 52b that supports the cover part 52a movably (openable and closable). Here, "arranged so as to cover the rotation center A1 of the workpiece W" means that the cover part 52a is arranged so as to overlap the rotation center A1 when viewed in a plane, and is arranged so as to completely block the part of the irradiation light irradiated to the rotation center A1 of the workpiece W. The support part 52b movably supports the cover part 52a between a position where the irradiation light L1 irradiated to the rotation center A1 is blocked (a position of the first state) and a position where the cover part 52a does not block the irradiation light L1 irradiated to the rotation center A1, for example, in a state where the cover part 52a is perpendicular to the optical axis of the irradiation light L1. The first state and the second state can be switched by moving the lid portion 52a with the support portion 52b. The movement of the lid portion 52a is controlled by, for example, the controller 100. Note that FIG. 1 shows a state in which the lid portion 52a is positioned so as to cover the rotation center A1 of the workpiece W.

The light shielding plate 54 functions as a light shielding member that adjusts the irradiation range of the irradiation light L1 emitted from the light source unit 42 (the range that the irradiation light L1 reaches on the surface of the workpiece W). The light shielding plate 54 includes an opening portion 54a that allows the irradiation light L1 to pass through. The light shielding plate 54 limits (adjusts) the irradiation range of the irradiation light L1 that reaches the workpiece W by only allowing the irradiation light L1 to pass through the opening portion 54a.

The details of the shape of the light shielding plate 54 will be described with reference to Figs. 2 and 3. Fig. 2(a) shows a schematic diagram of the irradiation area AR of the irradiation light L1 on the workpiece W when the light shielding plate 54 is not used. As described above, the irradiation light L1 is irradiated to one end of the workpiece W (the right end in Fig. 2(a)) while being irradiated near the center of the workpiece W. Here, as shown by the shading of the color in the irradiation area in Fig. 2(a), the illuminance of the irradiation light L1 gradually decreases from the central area CA, which is the center of the optical axis, toward the outside, and the illuminance is again high in the outer peripheral area OA. If such an area of high illuminance in the outer peripheral area OA overlaps with the outer peripheral part of the workpiece W, there is a risk that only the outer peripheral part of the workpiece W will be overexposed. In order to avoid such a situation, the irradiation area AR of the irradiation light L1 is set so that the outer peripheral area OA and the outer peripheral part of the workpiece W do not overlap (the irradiation area AR is shifted outward).

In FIG. 1, the shielding plate 51a, the light-transmitting plate 53, the lid portion 52a of the rotating center shutter 52, and the opening portion 54a of the shielding plate 54 are arranged in this order from the light source unit 42 toward the workpiece W. In this way, the shielding plate 51a is located closer to the light source unit 42, while the lid portion 52a is located closer to the workpiece W. This allows the shielding plate 51a to block light that is not diffused very much with a relatively small area, and also makes it possible to switch between shielding and opening (second state) in a correspondingly small space. On the other hand, because the lid portion 52a is closer to the workpiece W, the boundary of the irradiation range of the workpiece W is less likely to become unclear due to diffusion of light, meaning that the irradiation range of the central area of the workpiece W can be set with high precision.

The light-transmitting plate 53 is located closer to the light source 42, while the opening 54a is located closer to the workpiece W. At this time, the light-transmitting plate 53 can transmit the light while the difference in the intensity distribution between the inside and outside of the light is small and the light is not diffused much. Therefore, when the light is attenuated to a certain extent by transmission, the light can be attenuated overall while keeping the bias in the intensity distribution between the inside and outside of the light small. Note that the fact that at least an intensity distribution between the inside and outside of the light occurs can be understood by referring to FIG. 2 described later. On the other hand, the opening 54a determines the overall boundary of the irradiation area on the workpiece W, and since it is located closer to the workpiece W, it is possible to accurately determine the overall irradiation area with little influence of light diffusion.

The light-transmitting plate 53 is provided in a portion that divides the space below it, including the workpiece W, from the space above it, including the light source unit 42. Therefore, by providing the shielding plate 51a closer to the light source unit 42 than the light-transmitting plate 53, the connection between the support unit 51b, which switches between shielding and opening, and the shielding plate 51a is in a position that is divided from the space on the workpiece W side, making it easier to maintain the airtightness of the space on the workpiece W side.

Figure 2(b) shows a schematic diagram of the shape of the opening 54a of the light shielding plate 54. When the light source unit 42 irradiates the workpiece W while rotating the workpiece W at a predetermined rotational speed (angular speed) by the rotation support unit 25, the peripheral speed of the workpiece W is faster at the periphery than near the center. Taking this into consideration, the shape of the opening 54a of the light shielding plate 54 is set so that the irradiation area expands from the center of the workpiece W toward the periphery, as shown in Figure 2(b). The opening 54a is approximately fan-shaped and is defined by two radii 54x, 54x that extend from the center of rotation of the workpiece W toward the periphery (one end) of the workpiece W, and an arc 54y that connects the end points of the radii 54x.

As described above, the irradiation area AR is shifted outward so that the outer peripheral area OA of the irradiation light L1 does not overlap with the outer periphery of the workpiece W, which may cause the outer peripheral area OA of the irradiation light L1 to overlap with the center of rotation of the workpiece W (see FIG. 2(b)). In this case, there is a risk of the exposure amount at the center of rotation being excessive. The exposure amount at the center of rotation is adjusted by the opening and closing operation of the rotation center shutter 52 (details will be described later), but it is preferable to make the exposure amount as uniform as possible regardless of the opening and closing operation of the rotation center shutter 52.

Therefore, in the light shielding plate 54 of the substrate processing apparatus 1 according to this embodiment, the two radii 54x, 54x are not the radii of a straight line relative to the arc 54y (the radii shown by the dashed lines in FIG. 2B), but are recessed inward in the circumferential direction. Such an inward recessed shape is formed at least in the portion close to the center of rotation at the radii 54x, 54x. In this way, by making at least the portion close to the center of rotation at the radii 54x, 54x have an inward recessed shape, it is possible to reduce the amount of irradiation light passing through the light shielding plate 54 in the area close to the center of rotation. This makes it possible to effectively prevent the amount of exposure at the center of rotation from becoming excessive.

Figure 3 is a diagram illustrating the opening 54a of the light shielding plate 54. Now, when the illuminance E of the irradiated light L1 is not uniform and is determined according to the position, the shape of the opening 54a (including the shape of the recessed shape of the radii 54x and 54x described above) is adjusted so that the integral of the illuminance E along the circumferential path C is proportional to the radius r.

The amount of the irradiated light L1 emitted from the light source unit 42 is reduced by passing through the light amount adjustment mechanism 50, resulting in weak light. In this embodiment, "weak light" refers to light that causes a change in the temperature of the workpiece W when the light is irradiated to the workpiece W to be kept to less than 1°C relative to the external temperature (the temperature outside the housing 21, room temperature). In addition, the irradiated light L1 after passing through the light amount adjustment mechanism 50 can be adjusted to weak light in the entire irradiation area AR of the irradiated light L1 on the surface of the workpiece W.

Returning to FIG. 1, the measurement unit 60 has two illuminometers 61, 62 (first illuminometer, second illuminometer) that measure the illuminance of the irradiated light L1. The illuminometer 61 is provided at a position corresponding to the optical axis center A2 of the irradiated light L1 irradiated to the workpiece W that is supported and rotated by the rotation support part 25, more specifically, directly below the optical axis center A2. With this type of illuminometer 61, the illuminance of the optical axis center A2 of the irradiated light L1 is measured, and the deterioration status of the lamp itself of the light source unit 42, for example, can be appropriately identified.

As shown in FIG. 4, the illuminometer 62 is provided on the circumference of a circle Ci (circle Ci shown by a dashed line) centered on the optical axis center A2 and passing through the rotation center A1. That is, the illuminometer 62 is provided at any position where the distance from the optical axis center A2 is the same as that of the rotation center A1. In the example shown in FIG. 4, the illuminometer 62 is provided at a position symmetrical to the rotation center A1 with respect to the optical axis center A2. As will be described in detail later, the exposure amount is easily excessive at the rotation center A1, so the exposure amount is adjusted by opening and closing the rotation center shutter 52. In such an adjustment of the exposure amount, it is important to appropriately obtain the exposure amount (real-time exposure amount) at the rotation center A1 of the work W. However, since the θ axis of the rotation drive unit 27 is provided at the rotation center A1 of the work W (see FIG. 1), it is difficult to provide the illuminometer 62. Here, the illuminance of the irradiation light L1 is generally highest at the optical axis center A2, and the illuminance changes depending on the distance from the optical axis center A2. Therefore, by providing an illuminometer 62 on the circumference of a circle Ci that is centered on the optical axis center A2 and passes through the rotation center A1, it becomes possible to appropriately estimate the exposure amount at the rotation center A1 using the illuminometer 62 provided in an area with an illuminance similar to that at the rotation center A1.

The controller 100 controls the rotation support unit 25, the gas supply unit 30, the gas exhaust unit 32, the atmosphere adjustment unit 34, the light irradiation mechanism 40, and the light intensity adjustment mechanism 50.

The controller 100 is composed of one or more control computers. For example, the controller 100 has a circuit 120 shown in FIG. 5. The circuit 120 has one or more processors 121, a memory 122, a storage 123, and an input/output port 124. The storage 123 has a computer-readable storage medium such as a hard disk. The storage medium stores a program for causing the substrate processing apparatus 1 to execute the substrate processing procedure described below. The storage medium may be a removable medium such as a non-volatile semiconductor memory, a magnetic disk, or an optical disk. The memory 122 temporarily stores the program loaded from the storage medium of the storage 123 and the calculation results by the processor 121. The processor 121 configures each of the above-mentioned functional modules by executing the above-mentioned program in cooperation with the memory 122. The input/output port 124 inputs and outputs electrical signals between each part controlled by the controller 100 according to instructions from the processor 121.

The hardware configuration of the controller 100 is not necessarily limited to configuring each functional module by a program. For example, each functional module of the controller 100 may be configured by a dedicated logic circuit or an ASIC (Application Specific Integrated Circuit) that integrates the dedicated logic circuit.

The controller 100 is configured to execute a first control, a second control, a third control, and a fourth control. The second control is executed during the first control. The third control is executed after the second control. The fourth control is executed after the third control.

In the first control, the controller 100 controls the light irradiation mechanism 40 so that the workpiece W supported by the holding part 26 of the rotation support part 25 and rotating is irradiated with the irradiation light L1 while the rotation center shutter 52 is in the second state. Specifically, the controller 100 controls the light irradiation mechanism 40 so that the irradiation light L1 is irradiated only to a part of the area including the rotation center A1 of the workpiece W and the periphery (one end) of the workpiece W. Here, controlling the light irradiation mechanism 40 means, for example, adjusting the orientation of the light source part 42 so that the irradiation area of the irradiation light L1 becomes the intended area. As described above, the state in which the rotation center shutter 52 is in the second state is a state in which the lid part 52a is arranged in a position that does not block the part of the irradiation light L1 irradiated to the rotation center A1 of the workpiece W. That is, in the first control, the controller 100 controls the support part 52b so that the lid part 52a is arranged in a position that does not block the irradiation light L1 irradiated to the rotation center A1 of the workpiece W.

In the second control, the controller 100 determines whether the exposure amount at the rotation center A1 exceeds the threshold value based on the illuminance of the irradiation light L1 measured by the illuminometer 62 during the first control. As described above, the illuminometer 62 is provided on the circumference of a circle Ci that passes through the rotation center A1 and is centered on the optical axis center A2, and can measure an exposure amount that is close to the exposure amount at the rotation center A1. FIG. 6 is a graph showing an example of the dose amount (exposure amount) for each area of the workpiece W when the workpiece W is irradiated with the irradiation light L1 by the first control. In FIG. 6, the horizontal axis indicates the radial position of the workpiece W, and the vertical axis indicates the dose amount. In the first control described above, the area irradiated with the irradiation light L1 changes continuously in accordance with the rotation of the workpiece W for areas other than the rotation center A1 of the workpiece W, but the rotation center A1 of the workpiece W is always irradiated with the irradiation light L1. As a result, as shown in FIG. 6, only the rotation center A1 of the workpiece W is overexposed, which may result in uneven sensitivity of the workpiece W within its surface during exposure processing performed after irradiation with vacuum ultraviolet light. To avoid this situation, the controller 100 determines whether the amount of exposure at the rotation center A1 exceeds a threshold in the second control, and if it does, performs the third control described below, preventing overexposure of only the rotation center A1 of the workpiece W. This threshold value for the amount of exposure is set to a value that at least does not result in "overexposure of the rotation center A1."

In the third control, the controller 100 transitions the rotation center shutter 52 to the first state when it is determined in the second control that the exposure amount at the rotation center A1 exceeds the threshold value. The state in which the rotation center shutter 52 is in the first state is, as described above, the state in which the lid portion 52a is positioned in a position that always blocks the portion of the irradiation light L1 irradiated to the rotation center A1 of the workpiece W (the state shown in FIG. 1). That is, in the third control, the controller 100 controls the support portion 52b so that the lid portion 52a is positioned in a position that always blocks the irradiation light L1 irradiated to the rotation center A1 of the workpiece W.

Figure 7 is a diagram explaining the operation of the lid portion 52a. Note that the irradiation area AR of the irradiation light L1 shown in Figure 7 shows an example in which the portion around the rotation center A1 is made circular by the mask shape of the light shielding plate 54. During the first control, the lid portion 52a is positioned so as not to block the portion of the irradiation light L1 irradiated to the rotation center A1 as shown in Figure 7 (a). On the other hand, if it is determined in the second control that the exposure amount at the rotation center A1 exceeds the threshold value, the lid portion 52a is moved in the third control to a position where it always blocks the portion of the irradiation light L1 irradiated to the rotation center A1 as shown in Figure 7 (b).

In the fourth control, the controller 100 controls the light source unit 42 of the light irradiation mechanism 40 so that irradiation of the irradiation light L1 onto the workpiece W continues with the cover portion 52a of the rotation center shutter 52 in the first state (see FIG. 7(b)).

[Substrate Processing Method]
Next, a substrate processing method including an operation of the substrate processing apparatus will be described. In the substrate processing method shown in this embodiment, a workpiece W having a resist film formed thereon is irradiated with light including VUV light using the substrate processing apparatus 1 before exposure.

Figure 8 shows a flow diagram of the procedure for forming a resist pattern on the workpiece W.

In step S01, a resist liquid is applied to the surface of the workpiece W to form a resist film. The method for forming the resist film is not particularly limited. An underlayer film or the like may be formed on the surface of the workpiece W before the resist film is formed. At this stage, the resist film is formed on the entire surface of the workpiece W.

In step S02, light including VUV light is irradiated onto the surface of the workpiece W on which a resist film has been formed using the substrate processing apparatus 1. Irradiation light L1 from the light source unit 42 is irradiated onto the workpiece W held in the housing 21 as VUV light. Irradiation light L1 is light including VUV light. The operation of the substrate processing apparatus 1 in step S02 will be described below with reference to FIG. 9.

Figure 9 is a diagram explaining the operation sequence for VUV light irradiation. First, the gas exhaust unit 32 operates to draw a vacuum and reduce the pressure inside the housing 21 (see Figure 9(a)). Then, with the gas supply unit 30 and gas exhaust unit 32 stopped, the workpiece W is carried into the housing 21 by the transport mechanism, and the workpiece W is placed on the holder 26 of the rotation support unit 25 (see Figure 9(b)). After that, the valve 30b of the gas supply unit 30 is opened and N2 purging is performed inside the housing 21.

Next, the N2 purge is stopped and the gate valve 23 is closed to make the inside of the housing 21 airtight (see FIG. 9(c)). At this time, the inside of the housing 21 is set to, for example, an atmospheric atmosphere at standard pressure. After that, the gas exhaust unit 32 operates to perform rough exhaust of the chamber for about 30 seconds, and the pressure inside the housing 21 is reduced (see FIG. 9(d)).

Then, the main chamber exhaust is carried out for about 5 seconds, and the pressure inside the housing 21 is reduced to about 0.02 Pa (see FIG. 9(e)). This reduced pressure state is then continued for about 30 seconds (see FIG. 9(f)).

Then, the valve 30b of the gas supply unit 30 is opened to supply Ar gas into the housing 21 (see FIG. 9(g)). As a result, an Ar gas atmosphere is formed in the housing 21, and the pressure inside the housing 21 increases. The decompression rate and the pressure increase rate can be controlled by the operation of the gas supply unit 30 and the gas exhaust unit 32. The decompression rate and the pressure increase rate may be constant or may be changed midway.

When the pressure inside the housing 21 reaches, for example, 10,000 Pa due to the Ar gas, the lamp shutter 51 is opened (the irradiation light L1 from the light source unit 42 reaches the workpiece W) while maintaining the pressure inside the housing 21 (see FIG. 9 (h)).

Then, while the workpiece W is rotated by the rotation support 25, the light source 42 irradiates the workpiece W with light including VUV light for, for example, about 31 seconds (see FIG. 9(i)). If it is determined during this that the exposure amount at the rotation center A1 exceeds the threshold value, the cover 52a is moved to a position that blocks the irradiation light L1 irradiated to the rotation center A1 of the workpiece W.

After the light source 42 has been irradiated for a predetermined time (e.g., about 31 seconds), the light irradiation is stopped and the lamp shutter 51 is closed (a state in which the irradiated light L1 from the light source 42 does not reach the workpiece W) (see FIG. 9(j)). Then, the operation of the gas supply unit 30 and the gas exhaust unit 32 is stopped. After that, the valve 30b of the gas supply unit 30 is opened to perform N2 purging in the housing 21, and the pressure in the housing 21 is returned to the atmospheric atmosphere (see FIG. 9(k)). Finally, the workpiece W is transported out of the housing 21 (see FIG. 9(l)). With the above, the processing of the workpiece W by the substrate processing apparatus 1 is completed.

The amount of light per unit area when irradiating light containing VUV light (sometimes called cumulative irradiation amount or dose) is made smaller than when irradiating the surface of the workpiece W with light containing VUV light after irradiating a resist pattern. Specifically, compared to when irradiating the surface of the workpiece W with light containing VUV light after forming a resist pattern by exposure and development processing to improve surface roughness, the amount of irradiation of light containing VUV light is adjusted to 1% to 2%. For example, when irradiating a resist pattern with light containing VUV light, the amount of light containing VUV light can be adjusted to 25 mj/cm ² to 100 mj/cm ^2. On the other hand, when irradiating a resist film before exposure processing with light containing VUV light, the amount of light containing VUV light can be adjusted to about 1 mj/cm ² to 2 mj/cm ^2. In this way, when irradiating a resist film before exposure processing with light containing VUV light, the amount of irradiation light can be adjusted to be small.

Returning to FIG. 8, in step S03, a heat treatment is performed on the workpiece W after it has been irradiated with light including VUV light. The heat treatment at this stage is a heat treatment on the unsolidified resist film, and is a heat treatment called PAB (Pre Applied Bake).

In step S04, an exposure process is performed on the workpiece W after the heating process (PAB). In the exposure process, an energy beam is irradiated onto the exposure target portion of the resist film formed on the workpiece W using a method such as immersion exposure.

In step S05, the workpiece W after the exposure process is subjected to a heating process. The heating process at this stage is a heating process for the unsolidified resist film, and is a heating process called PEB (Post Exposure Bake).

In step S06, a development process is performed on the workpiece W after the heat treatment (PEB). In the development process, a developer is applied to the surface of the workpiece W, and then the developer is washed away with a rinse liquid. This forms a predetermined pattern on the surface of the workpiece W. Note that a heat treatment (PB: Post Bake) may be performed again after the development process. Note that the coating process, heating process (PAB, PEB), exposure process, and development process described in steps S01 and S03 to S06 can be performed using, for example, a substrate processing system including a known coating/developing apparatus and exposure apparatus.

By carrying out the above series of processes, the exposure sensitivity of the resist film is improved compared to conventional substrate processing methods, and the roughness of the resist pattern after exposure and development processing is also improved.

[Effect]
In the substrate processing apparatus 1 according to the present embodiment, the irradiation light L1 including vacuum ultraviolet light is irradiated only to a part of the area of the rotating workpiece W including the center of rotation A1 and the periphery (one end) of the workpiece W. Since the workpiece W is rotating, even if the irradiation light L1 is irradiated only to a part of the area of the workpiece W, the irradiation light L1 can be irradiated to substantially the entire area of the workpiece W. In a configuration in which the irradiation light L1 is irradiated only to a part of the area of the workpiece W, the light source unit 42 can be disposed closer to the workpiece W than in a configuration in which the irradiation light L1 is irradiated to the entire area of the workpiece W, so that the chamber volume can be reduced. Here, in a configuration in which the irradiation light L1 is irradiated only to a part of the area of the workpiece W, the area irradiated with the irradiation light L1 continuously changes in accordance with the rotation of the workpiece W with respect to the area other than the center of rotation A1 of the workpiece W. On the other hand, the irradiation light L1 is always irradiated to the center of rotation A1 of the workpiece W. As a result, only the rotation center A1 of the workpiece W is overexposed, and as a result, the sensitivity of the workpiece W may become non-uniform within the surface during exposure processing after irradiation with vacuum ultraviolet light. In this regard, in the substrate processing apparatus 1 according to the present embodiment, the cover portion 52a can be arranged at a position that blocks the irradiation light L1 irradiated to the rotation center, so that overexposure of only the rotation center A1 of the workpiece W is appropriately suppressed. This makes it possible to improve the in-surface uniformity of the irradiation of the irradiation light L1 (light including vacuum ultraviolet light) to the workpiece W before the exposure processing, and as a result, it is possible to improve the in-surface uniformity of the sensitivity during the exposure processing of the workpiece W. As described above, according to the substrate processing apparatus 1 according to the present embodiment, the sensitivity during the exposure processing of the workpiece W using a resist material suitable for EUV lithography can be made uniform within the surface.

In addition, in the substrate processing apparatus 1, based on the illuminance of the irradiation light L1 measured by the illuminometer 62 of the measuring unit 60, it is determined whether the exposure amount at the rotation center A1 of the workpiece W exceeds a predetermined threshold value. If it is determined that the exposure amount exceeds the predetermined threshold value, the cover portion 52a is transitioned to a first state in which the portion of the irradiation light L1 irradiated to the rotation center is blocked, and the irradiation of the irradiation light L1 to the workpiece W is continued in the first state. According to this configuration, when the exposure amount at the rotation center A1 of the workpiece W exceeds the predetermined threshold value, the irradiation light L1 is not irradiated to the rotation center A1 of the workpiece W thereafter. This appropriately prevents excessive exposure only at the rotation center A1 of the workpiece W. This makes it possible to improve the in-plane uniformity of the irradiation of the irradiation light L1 (light including vacuum ultraviolet light) to the workpiece W before the exposure process, and as a result, the in-plane uniformity of the sensitivity during the exposure process of the workpiece W can be improved.

The measuring unit 60 has, as a plurality of illuminometers, an illuminometer 61 provided at a position corresponding to the optical axis center A2 of the irradiation light L1 irradiated in the first control, and an illuminometer 62 provided on the circumference of a circle Ci passing through the rotation center A1 centered on the optical axis center A2. By providing the illuminometer 61 at a position corresponding to the optical axis center A2 of the irradiation light L1, the illuminance of the center of the irradiation light L1 can be measured by the illuminometer 61, so that it is possible to appropriately identify the deterioration state of the light source unit 42 itself based on the illuminance measured by the illuminometer 61. In addition, as described above, it is important to appropriately obtain the exposure amount at the rotation center A1 of the work W, but usually, the rotation drive unit 27 is provided at the rotation center A1 of the work W, making it difficult to provide an illuminometer. Here, the illuminance of the irradiation light L1 is generally highest at the optical axis center A2, and the illuminance changes depending on the distance from the optical axis center A2. Therefore, by providing an illuminometer 62 on the circumference of a circle Ci that is centered on the optical axis center A2 and passes through the rotation center A1, it becomes possible to appropriately estimate the exposure amount at the rotation center A1 using the illuminometer 62 provided in an area with an illuminance similar to that at the rotation center A1.

In the second control, the controller 100 determines whether the exposure amount at the rotation center A1 exceeds the threshold value based on the illuminance of the irradiated light L1 measured by the illuminometer 62 during the first control. With this configuration, it is possible to estimate the exposure amount at the rotation center A1 during the first control, and the first to fourth controls described above can be performed quickly and easily.

The rotation center shutter 52 has a lid portion 52a that can be positioned to cover the rotation center A1, and in the first state, the controller 100 positions the lid portion 52a in a position that blocks the irradiation light L1 irradiated to the rotation center A1. In the second state, the controller 100 positions the lid portion 52a in a position that does not block the irradiation light L1. In this manner, by switching between the first state and the second state by opening and closing the lid, it is possible to realize exposure adjustment at the optical axis center A2 with a simple configuration.

The substrate processing apparatus 1 further includes a light shielding plate 54 that limits the irradiation range of the irradiation light L1 that reaches the workpiece W by passing the irradiation light L1 only through the opening portion 54a. The opening portion 54a of the light shielding plate 54 has a roughly sector shape defined by two radii 54x, 54x that extend from the center of rotation A1 toward the periphery (one end) of the workpiece W, and an arc 54y that connects the end points of the radius 54x. The radius 54x of the opening portion 54a is recessed inward in the circumferential direction, at least in the portion close to the center of rotation A1.

As described above, the illuminance of the irradiated light L1 is generally highest at the optical axis center A2, and the illuminance changes depending on the distance from the optical axis center A2, but there may be an area where the illuminance becomes high again near the outer periphery of the irradiation range. If such a high-illuminance part near the outer periphery of the irradiated light L1 is irradiated to the outer periphery of the workpiece W, which is the periphery (one end) of the workpiece W, there is a risk that only the outer periphery of the workpiece W will be exposed to excessive light. In order to prevent such a situation, for example, it is possible to shift the irradiation range of the irradiated light L1 outward so that the above-mentioned area where the illuminance is high near the outer periphery is not irradiated to the outer periphery of the workpiece W. However, in this case, by shifting the irradiation range of the irradiated light L1 outward, there is a risk that the area where the illuminance is high near the outer periphery of the irradiated light L1 is located at the rotation center A1 of the workpiece W, which may cause a problem of excessive exposure to the rotation center A1. In this regard, the opening 54a of the light shielding plate 54 is formed in a generally sector shape, and the portion of the opening 54a close to the rotation center A1 at the radius 54x, 54x is formed in a shape recessed inward in the circumferential direction. This makes it possible to reduce the amount of irradiation light L1 passing through the light shielding plate 54 in the area close to the rotation center A1, and effectively prevents the amount of exposure at the rotation center A1 from becoming excessive.

[Modification]
Although various exemplary embodiments have been described above, the present invention is not limited to the exemplary embodiments described above, and various omissions, substitutions, and modifications may be made. In addition, elements in different embodiments may be combined to form other embodiments.

For example, the example of the rotation center shutter 52 has been described as a shielding section configured to be able to transition between the first state and the second state, but the shielding section may have other configurations. For example, the shielding section may be a shutter section 152 shown in FIG. 10. As shown in FIG. 10(a), the shutter section 152 is disposed on the upper part of the light shielding plate 54 so as to overlap the light shielding plate 54. Note that the opening portion 54a of the light shielding plate 54 shown in FIG. 10 has a circular portion 54z around the rotation center A1. The shutter section 152 is circular, and an opening 152a is formed in a partial area. The opening 152a is a circular opening. The shutter section 152 is configured to be able to rotate.

In this configuration, the controller 100 controls the shutter section 152 in the first state so that the portions of the shutter section 152 other than the opening 152a block the irradiation light L1 irradiated to the rotation center A1. In this case, the shutter section 152 is, for example, stationary and does not rotate. On the other hand, the controller 100 rotates the shutter section 152 in the second state as shown in FIG. 10(b). This controls the shutter section 152 so that a state in which the irradiation light L1 that passes through the opening 152a is irradiated to the rotation center A1 and a state in which the portions other than the opening 152a block the irradiation light L1 irradiated to the rotation center A1 are alternately repeated.

With this configuration, after it is determined that the exposure amount at the rotation center A1 exceeds the threshold, the irradiated light irradiated to the rotation center A1 is reliably blocked by the parts of the shutter unit 152 other than the opening 152a. On the other hand, in a state (second state) in which it is determined that the exposure amount at the rotation center A1 does not yet exceed the threshold, the shutter unit 152 rotates. As a result, a state in which the irradiated light L1 that has passed through the opening 152a of the shutter unit 152 is irradiated to the rotation center A1 and a state in which the parts other than the opening 152a block the irradiated light L1 irradiated to the rotation center A1 are alternately repeated. As a result, in the second state, it becomes possible to adjust the exposure amount at the rotation center by the rotation speed (number of rotations) of the shutter unit 152, making it possible to adjust the exposure amount more finely.

Also, as shown in FIG. 11(a), the controller 100 may control the light irradiation mechanism 240 (light source) so that the portion of the irradiation light L1 irradiated to the rotation center A1 in the first control is irradiated to the illuminometer 62 when the workpiece W is not supported by the holding unit 26. This control (fifth control) may be performed, for example, before the workpiece W is loaded, or during so-called idle time. As shown in FIG. 11(b), the light irradiation mechanism 240 has a light source unit 42, a motor 201, and a belt 202. The belt 202 is a member that transmits the drive from the motor 201 to the light source unit 42. The motor 201 rotates the light source unit 42 by 180° via the belt 202 by its driving force (changing the orientation of the light source unit 42), thereby changing the irradiation position of the irradiation light L1 irradiated from the light source unit 42. In this configuration, when the first control is not being performed and the workpiece W is not supported by the holder 26, the motor 201 is driven to rotate the light source unit 42, so that the portion of the irradiated light L1 that is irradiated to the rotation center A1 in the first control is irradiated to the illuminometer 62. Then, in the second control, the controller 100 determines whether the exposure amount at the rotation center A1 exceeds the threshold value based on the illuminance of the irradiated light L1 measured by the illuminometer 62 during the fifth control and, for example, the elapsed time from the start of the first control.

As described above, the illuminance of the irradiation light L1 changes roughly according to the distance from the optical axis center A2, but even on the circumference of a circle that passes through the rotation center A1 and the optical axis center A2, the illuminance is not strictly the same at the actual rotation center A1 and other points on the circumference. In this respect, in the fifth control, which is different from the first control, the orientation of the light source unit 42 is adjusted so that the portion of the irradiation light irradiated to the rotation center A1 in the first control is irradiated by the illuminometer 62. This makes it possible to obtain an illuminance closer to the illuminance of the portion of the irradiation light L1 that is actually irradiated to the rotation center A1 in the first control. Then, the exposure amount at the rotation center A1 is estimated based on the illuminance obtained in this way, thereby improving the estimation accuracy of the exposure amount, and as a result, the in-plane uniformity of the irradiation of the irradiation light L1 to the workpiece W before the exposure process can be further improved.

Also, as shown in Figures 12(a) and 12(b), the light source unit 42 may be arranged in a position where the irradiation light L1 is irradiated from an oblique direction onto the workpiece W. With this configuration, compared to a case where the irradiation light L1 is arranged perpendicular to the workpiece W, the light source unit 42 can be brought closer to the workpiece W and the irradiation light can be irradiated onto a larger area. In other words, a configuration in which the irradiation light L1 is irradiated from an oblique direction onto the workpiece W is preferable for irradiating the irradiation light L1 onto a necessary and sufficient area while keeping the chamber volume small.

Furthermore, as shown in FIG. 12(b), the light source unit 42 may be arranged at a position where the distance to one end Wa (one end on the side where the irradiation light L1 is irradiated) which is the periphery of the workpiece W is closer than the distance to the rotation center A1. When the light source unit 42 is arranged so that the irradiation light L1 is irradiated to the workpiece W from an oblique direction, the distance from the light source unit 42 to each area of the workpiece W is not constant. The closer the distance from the light source unit 42, the greater the exposure amount. If the distance from the light source unit 42 to the rotation center A1 is shortened, the exposure amount will be further increased at the rotation center where the irradiation light L1 is always irradiated and the exposure amount is large. In this regard, by making the distance from the light source unit 42 to one end Wa of the workpiece W shorter than the distance from the light source unit 42 to the rotation center A1, it is possible to suppress the exposure amount at the rotation center A1 from becoming excessive.

Also, as shown in FIG. 13(a), a plurality of light source units 542, 642, 742, and 842 may be arranged as the light source unit. In such a configuration, for example, by opening and closing the lamp shutter 351, a state in which the irradiation light L1 from each light source unit 542, 642, 742, and 842 reaches the workpiece W and a state in which it does not reach the workpiece W are switched. As shown in FIG. 13(b), for example, first, the irradiation light L1 is irradiated from the light source unit 542, and the irradiation light L1 that passes through the opening portion 354a of the light shielding plate 354 is irradiated onto the workpiece W. Then, for example, when the lamp of the light source unit 542 becomes unable to irradiate due to its lifespan, the light source unit that irradiates the irradiation light L1 is switched to the light source unit 642, and the irradiation light L1 irradiated by the light source unit 642 is irradiated onto the workpiece W. The lamp is replaced, for example, every three months, and the maintenance cycle for lamp replacement can be extended by arranging a plurality of light source units and switching them as in this configuration.

1...substrate processing apparatus, 25...rotation support section (substrate support section), 40, 240...light irradiation mechanism (light source), 51a...shielding plate (shutter), 52...rotation center shutter (shielding section), 52a...lid section, 53...light-transmitting plate, 54...light-shielding plate, 54a...opening section, 54x...radius, 54y...arc, 60...measuring section, 61, 62...illuminometer (first illuminometer, second illuminometer), 100...controller (control section), 152...shutter section, A1...rotation center, A2...optical axis center, W...work (substrate).

Claims (11)

a substrate support configured to be capable of supporting, while rotating, a substrate on which a resist film made of a resist material for EUV lithography is formed;
a light source that emits irradiation light including vacuum ultraviolet light;
a shutter that switches between a state in which the irradiation light reaches the substrate and a state in which the irradiation light does not reach the substrate by moving between an area on the optical path of the irradiation light and an area other than the optical path;
a light-transmitting plate that transmits the irradiation light;
a light shielding plate that limits an irradiation range of the irradiation light reaching the substrate by allowing the irradiation light to pass through only an opening portion;
a shielding portion that can be arranged at a position to block the irradiation light that is irradiated to a rotation center of the substrate that is supported and rotated by the substrate support portion,
the irradiation light is irradiated onto a part of a surface of the substrate, the part being continuous in a radial direction ;
the shutter, the light-transmitting plate, the shielding portion, and the light-shielding plate are arranged in this order from the light source toward the substrate . a substrate support configured to be capable of supporting, while rotating, a substrate on which a resist film made of a resist material for EUV lithography is formed;
a light source that emits irradiation light including vacuum ultraviolet light;
a shutter that switches between a state in which the irradiation light reaches the substrate and a state in which the irradiation light does not reach the substrate by moving between an area on the optical path of the irradiation light and an area other than the optical path;
a light-transmitting plate that transmits the irradiation light;
a light shielding plate that limits an irradiation range of the irradiation light reaching the substrate by allowing the irradiation light to pass through only an opening portion;
a shielding portion that can be arranged at a position to block the irradiation light that is irradiated to a rotation center of the substrate that is supported and rotated by the substrate support portion,
the irradiation light is irradiated onto a part of a surface of the substrate, the part being continuous in a radial direction;
a measurement unit having one or more illuminometers for measuring the illuminance of the irradiation light;
A control unit,
the shielding unit is configured to be capable of transitioning between a first state in which the shielding unit always blocks a portion of the irradiation light irradiated to a rotation center of the substrate and a second state which is a state other than the first state;
The control unit is
a first control for controlling the light source with the shielding unit in the second state so that the irradiation light is irradiated only onto a partial region of the substrate, the region including a rotation center of the substrate and one end of the substrate, the substrate being supported and rotated by the substrate support unit;
and a second control for determining whether or not an exposure amount at the rotation center exceeds a predetermined threshold based on the illuminance of the irradiation light measured by the illuminometer.
the measurement unit has, as the plurality of illuminometers, a first illuminometer provided at a position corresponding to an optical axis center of the irradiation light irradiated in the first control, and a second illuminometer provided on a circumference of a circle passing through the center of rotation centered on the optical axis center,
In the second control, the control unit determines whether the exposure amount at the center of rotation exceeds the threshold value based on the illuminance of the irradiation light measured by the second illuminometer during the first control. a substrate support configured to be capable of supporting, while rotating, a substrate on which a resist film made of a resist material for EUV lithography is formed;
a light source that emits irradiation light including vacuum ultraviolet light;
a shutter that switches between a state in which the irradiation light reaches the substrate and a state in which the irradiation light does not reach the substrate by moving between an area on the optical path of the irradiation light and an area other than the optical path;
a light-transmitting plate that transmits the irradiation light;
a light shielding plate that limits an irradiation range of the irradiation light reaching the substrate by allowing the irradiation light to pass through only an opening portion;
a shielding portion that can be arranged at a position to block the irradiation light that is irradiated to a rotation center of the substrate that is supported and rotated by the substrate support portion,
the irradiation light is irradiated onto a part of a surface of the substrate, the part being continuous in a radial direction;
a measurement unit having one or more illuminometers for measuring the illuminance of the irradiation light;
A control unit,
the shielding unit is configured to be capable of transitioning between a first state in which the shielding unit always blocks a portion of the irradiation light irradiated to a rotation center of the substrate and a second state which is a state other than the first state;
The control unit is
a first control for controlling the light source with the shielding unit in the second state so that the irradiation light is irradiated only onto a partial region of the substrate, the region including a rotation center of the substrate and one end of the substrate, the substrate being supported and rotated by the substrate support unit;
a second control for determining whether or not an exposure amount at the rotation center exceeds a predetermined threshold based on the illuminance of the irradiation light measured by the illuminometer;
a third control for transitioning the shielding portion to the first state when it is determined in the second control that the exposure amount at the rotation center is greater than the threshold value;
a fourth control for controlling the light source so that the irradiation of the irradiation light onto the substrate is continued with the shielding unit in the first state,
the measurement unit includes, as the plurality of illuminometers, a first illuminometer provided at a position corresponding to an optical axis center of the irradiation light irradiated in the first control, and a second illuminometer provided on a circumference of a circle passing through the center of rotation centered on the optical axis center,
In the second control, the control unit determines whether the exposure amount at the center of rotation exceeds the threshold value based on the illuminance of the irradiation light measured by the second illuminometer during the first control. a substrate support configured to be capable of supporting, while rotating, a substrate on which a resist film made of a resist material for EUV lithography is formed;
a light source that emits irradiation light including vacuum ultraviolet light;
a shutter that switches between a state in which the irradiation light reaches the substrate and a state in which the irradiation light does not reach the substrate by moving between an area on the optical path of the irradiation light and an area other than the optical path;
a light-transmitting plate that transmits the irradiation light;
a light shielding plate that limits an irradiation range of the irradiation light reaching the substrate by allowing the irradiation light to pass through only an opening portion;
a shielding portion that can be arranged at a position to block the irradiation light that is irradiated to a rotation center of the substrate that is supported and rotated by the substrate support portion,
the irradiation light is irradiated onto a part of a surface of the substrate, the part being continuous in a radial direction;
a measurement unit having one or more illuminometers for measuring the illuminance of the irradiation light;
A control unit,
the shielding unit is configured to be capable of transitioning between a first state in which the shielding unit always blocks a portion of the irradiation light irradiated to a rotation center of the substrate and a second state which is a state other than the first state;
The control unit is
a first control for controlling the light source with the shielding unit in the second state so that the irradiation light is irradiated only onto a partial region of the substrate, the region including a rotation center of the substrate and one end of the substrate, the substrate being supported and rotated by the substrate support unit;
a second control for determining whether or not an exposure amount at the rotation center exceeds a predetermined threshold based on the illuminance of the irradiation light measured by the illuminometer;
a third control for transitioning the shielding portion to the first state when it is determined in the second control that the exposure amount at the rotation center is greater than the threshold value;
a fourth control for controlling the light source so that the irradiation of the irradiation light onto the substrate is continued with the shielding unit in the first state,
the measurement unit includes, as the plurality of illuminometers, a first illuminometer provided at a position corresponding to an optical axis center of the irradiation light irradiated in the first control, and a second illuminometer provided on a circumference of a circle passing through the center of rotation centered on the optical axis center,
The control unit is
a fifth control is further performed to control the light source such that a portion of the irradiation light irradiated onto the rotation center in the first control is irradiated onto the second illuminometer in a state in which the substrate is not supported by the substrate support portion;
In the second control, the substrate processing apparatus determines whether or not the exposure amount at the rotation center exceeds the threshold value based on the illuminance of the irradiation light measured by the second illuminometer during the fifth control. 5. The substrate processing apparatus according to claim 2, wherein the shutter, the light-transmitting plate, the shielding portion, and the light-shielding plate are arranged in this order from the light source toward the substrate. the shielding portion has a lid portion configured to be arranged so as to cover the rotation center,
The substrate processing apparatus of any one of claims 2 to 5, wherein the control unit, in the first state, positions the lid portion in a position that blocks the irradiation light irradiated to the center of rotation, and, in the second state, positions the lid portion in a position that does not block the irradiation light. The shielding portion has an opening formed therein and a shutter portion configured to be rotatable,
The substrate processing apparatus of any one of claims 2 to 5, wherein the control unit positions the shutter unit so that, in the first state, portions of the shutter unit other than the opening block the irradiation light irradiated to the center of rotation, and, in the second state, controls the shutter unit by rotating the shutter unit so that a state in which the irradiation light that has passed through the opening is irradiated to the center of rotation and a state in which portions other than the opening block the irradiation light irradiated to the center of rotation are alternately repeated. The substrate processing apparatus according to claim 1 , wherein the light source is disposed at a position where the irradiation light is irradiated from an oblique direction onto the substrate. The substrate processing apparatus according to claim 8 , wherein the light source is disposed at a position closer to one end of the substrate than to the center of rotation. Executing a first control in which irradiation light is applied to a rotating substrate on which a resist film made of a resist material for EUV lithography is formed, only to a partial region of the substrate including a rotation center and one end portion of the substrate;
During the first control, a second control is executed to determine whether or not an exposure amount at the rotation center exceeds a predetermined threshold value based on an illuminance of the irradiation light measured by an illuminometer provided on a circumference of a circle passing through the rotation center centered on an optical axis center of the irradiation light;
disposing a shielding portion to block a portion of the irradiation light irradiated to the rotation center when it is determined that the exposure amount at the rotation center is greater than the threshold value;
and continuing to irradiate the substrate with the irradiation light while the shielding portion is placed. A computer-readable storage medium storing a program for causing an apparatus to execute the substrate processing method according to claim 10 .

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