JP6951926B2 - Exposure device - Google Patents

Description

The present invention relates to an exposure apparatus that projects a pattern onto a substrate on which a photoresist layer (photosensitive material) is formed on a surface using a photomask, a light modulation element array, or the like, and more particularly to a configuration of an illumination optical system.

In a projection exposure device (stepper or the like), a maskless exposure device, or the like, light emitted from a light source is guided to a photomask, a light modulation element array, or the like through an illumination optical system. The light transmitted or reflected through the photomask and the light modulation element array is imaged on the substrate surface by the projection optical system, and the pattern light is projected onto the substrate. As the light source, for example, a discharge lamp can be applied.

The sensitivity characteristics of the photoresist formed on the substrate surface differ depending on the material of the photoresist and the like. Therefore, if the substrate is irradiated with light including a specific wavelength range, the pattern resolution or the like may be hindered. However, the light emitted from the discharge lamp generally has a continuous and wide spectral distribution with peaks (bright lines) at 436 nm (g line), 405 nm (h line), and 365 nm (i line), respectively.

Therefore, it is known that an optical filter for reducing the intensity of ultraviolet rays in a specific wavelength range is provided in the illumination optical system. By arranging the optical filter on the optical path, patterned light having a light intensity distribution suitable for the sensitivity characteristics of the photoresist is projected on the substrate (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2001-296666

When the light is incident on the filter in a converged or diffused state, the incident angle on the filter surface greatly differs depending on the incident position. As a result, the attenuation wavelength range shifts due to the incident angle dependence of the filter, and the wavelength shift balance changes. In particular, when having a continuous light intensity distribution having a plurality of emission lines, wavelength shift is likely to occur. As a result, a light intensity distribution suitable for the photoresist cannot be obtained, resulting in a decrease in pattern resolution.

Therefore, there is a need for an illumination optical system capable of obtaining a light intensity distribution suitable for a photoresist by using a filter that reduces the light intensity in a specific wavelength range.

The exposure apparatus of the present invention can be configured as a maskless exposure apparatus, a projection exposure apparatus (stepper, etc.), and a contact exposure apparatus, and includes a light source that emits light having a continuous light intensity distribution and a light source having an elliptical mirror. A unit and an illumination optical system that illuminates the irradiation surface with light from the light source unit are provided.

The illumination optical system of the present invention includes a condensing optical system that condenses light from the light source unit, an illuminance uniforming optical system that makes the illuminance uniform by incident light from the condensing optical system, and the above-mentioned collection. The condensing optical system is provided with an optical filter that is arranged closer to the light source portion than the optical optical system, is movable between the optical path and the outside of the optical path, and attenuates the light intensity in a predetermined wavelength region, and the condensing optical system is the ellipse. It is arranged closer to the light source than the second focal position of the mirror.

The condensing optical system can be configured as a refraction type optical system, for example, a convex lens. Further, the illuminance uniform optical system can include a rod lens. The discharge lamp emits light including, for example, g-line, h-line, and i-line, and the optical filter attenuates the light intensity in the wavelength range including at least one emission line of g-line, h-line, and i-line.

The maximum incident angle Θa formed by the optical axis of the illumination optical system when light is incident on the optical filter is smaller than the maximum incident angle Θb formed by the optical axis when light is incident on the illuminance uniform optical system. It can be configured as follows. Further, the focusing angle of the focusing optical system can be made larger than the NA of the illumination optical system. Alternatively, the distance between the condensing optical system and the incident surface of the illuminance equalizing optical system can be made shorter than the focal length of the condensing optical system.

It is possible to provide a relay optical system that is arranged between the illuminance uniform optical system and the irradiation surface and projects an image of the emission surface of the illuminance uniform optical system onto the irradiation surface. The relay optical system can illuminate the irradiation surface at the same magnification or at a predetermined magnification with respect to the emission surface of the illuminance uniform optical system.

The optical filter can be composed of a plurality of optical filters that attenuate light in different wavelength ranges, and includes a filter insertion amount adjusting unit for adjusting the amount of the plurality of optical filters inserted into the optical path. Can be done. Then, the optical filter having a relatively short reduced wavelength region among the plurality of optical filters can be arranged closer to the light source portion than the optical filter having a relatively long reduced wavelength region. For example, a plurality of optical filters can be arranged from the light source side in ascending order of the reduced wavelength range.

When a plurality of optical filters are arranged, the reflected light hits the other optical filters and causes deterioration. In order to prevent this, deterioration can be suppressed by arranging an optical filter that reduces light having a shorter wavelength on the light source side. This can also be realized by an exposure apparatus provided with the following illumination optical system.

That is, the exposure apparatus includes a light source unit that emits light having a continuous light intensity distribution and an illumination optical system that illuminates the irradiation surface with light from the light source unit, and the illumination optical systems have different wavelength ranges from each other. It is provided with a plurality of optical filters for attenuating the light of the light and a filter insertion amount adjusting unit for adjusting the insertion amount of the plurality of optical filters on the optical path. However, it is arranged on the light source side of the optical filter having a relatively long reduced wavelength range.

The exposure apparatus according to another aspect of the present invention includes a light source that emits light having a continuous light intensity distribution, a light source unit provided with a parabolic mirror, and illumination that illuminates the irradiation surface with light from the light source unit. An illumination optical system including an optical system, the illumination optical system condenses the light from the light source unit, and the light from the condensing optical system is incident to make the illuminance uniform. And an optical filter that is arranged closer to the light source portion than the condensing optical system, is movable between the optical path and the outside of the optical path, and attenuates the light intensity in a predetermined wavelength region.

According to the present invention, in an exposure apparatus provided with a discharge lamp, a mask, a light modulation element array, and the like can be illuminated with light having a desired spectral distribution without impairing the resolution.

It is a block diagram which shows the whole structure of the exposure apparatus by 1st Embodiment. It is a figure which showed the structure of the illumination optical system. It is a figure which showed the relationship between the insertion distance of an optical filter, and the apparent incident angle of the light incident on an optical filter. It is a figure which showed the relationship between the insertion distance of an optical filter, and the apparent incident angle of the light incident on an optical filter, with the insertion distance different from FIG. 3A. It is a figure which showed the spectral distribution curve of the light emitted from a light source part. It is a figure which showed the spectral distribution when one optical filter is inserted. It is a figure which showed the spectral distribution when another optical filter was inserted. It is a figure which showed the spectrum distribution when the rest of the optical filters were inserted. It is a block diagram of the exposure apparatus which is a 2nd Embodiment. It is a block diagram of the exposure apparatus which is a 3rd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an overall configuration of an exposure apparatus according to the first embodiment.

The exposure apparatus 1 is a direct (maskless) exposure apparatus that exposes a pattern on a substrate W on which a photosensitive material such as a photoresist is formed on the surface. The exposure apparatus 1 includes a light source unit 20 composed of a plurality of discharge lamps (not shown here) and a plurality of exposure heads 10 for projecting pattern light onto the substrate W, respectively. Here, only the light source unit 20 and the exposure head 10 of one system are shown.

The discharge lamp 20D of the light source unit 20 is a high-pressure or ultra-high pressure mercury lamp, and contains, for example, 0.2 mg / mm ³ or more of mercury. The light emitted by the discharge lamp is light including emission lines of g-line (436 nm), h-line (405 nm), and i-line (365 nm), and has a continuous spectral distribution in the range of about 330 nm to 480 nm. The discharge lamp 20D is lit by the lamp power supply 21.

The exposure head 10 includes an illumination optical system 11, a DMD 22 (optical modulation element array) in which a plurality of minute micromirrors are arranged in a matrix, and an imaging optical system 23, and other exposure heads are similarly configured. ing. When CAD / CAM data composed of vector data or the like is transmitted to the exposure apparatus 1, the raster conversion circuit 26 converts the vector data into raster data and sends it to the DMD drive circuit 24.

Each micromirror of the DMD 22 can selectively switch the light reflection direction by changing the posture, and the DMD drive circuit 24 controls each micromirror ON / OFF according to the raster data. As a result, light corresponding to the pattern is projected onto the surface of the substrate W by the imaging optical system 23.

The exposure operation of the exposure apparatus 1 is controlled by the controller (exposure operation control unit) 30. The exposure stage drive mechanism 19 moves the exposure stage 18 on which the substrate W is mounted relative to the exposure head 10 according to the control signal from the controller 30. The position measurement unit 27 calculates the exposure position on the surface of the substrate W based on the signal sent from the exposure stage drive mechanism 19. The direction along the moving path of the stage is defined as the main scanning direction X, and the direction orthogonal to the direction along the moving path is defined as the sub-scanning direction Y.

During the exposure operation, the exposure stage 18 moves at a constant speed along the scanning direction X. The projection area (hereinafter referred to as an exposure area) by the entire DMD 22 moves relatively on the surface of the substrate W as the substrate W moves. The exposure operation is performed according to a predetermined exposure pitch, and the micromirror is controlled to project the light of the pattern exposure according to the exposure pitch.

FIG. 2 is a diagram showing the configuration of the illumination optical system 11. Hereinafter, the configuration of the illumination optical system 11 will be described in detail. However, only the optical element corresponding to one discharge lamp is shown.

An elliptical mirror 20M that reflects the light emitted from the discharge lamp 20D in a predetermined direction and collects the light is attached to the light source unit 20 together with the discharge lamp 20D that emits light radially. The discharge lamp 20D is arranged so that its center is near the first focal position of the elliptical mirror 20M.

On the optical path of the illumination optical system 11 from the light source unit 20 to the DMD incident surface 22P, a wavelength adjustment mechanism 12, a condenser lens (condensing optical system) 14, and a rod lens (illumination uniformizing optical system) 15 are provided. The relay optical system 16 is arranged along the optical axis X in order from the light source unit 20 side. However, the optical axis X represents a straight line connecting the focal point of the elliptical mirror 20M and the center of the rod lens 15.

The wavelength adjustment mechanism 12 is a filter mechanism that selectively attenuates the spectral distribution (light intensity) of the illumination light, and includes optical filters 13A, 13B, and 13C that attenuate the light intensity in different wavelength regions. The optical filters 13A, 13B, and 13C are installed so as to be inserted into the light flux on the optical path of the illumination optical system 11. The optical filter 13A attenuates the wavelength region of 300 nm to 380 nm, the optical filter 13B attenuates the wavelength region of 380 nm to 420 nm, and the optical filter 13C attenuates the wavelength region of 420 nm to 500 nm.

The condenser lens 14 collects the light reflected by the elliptical mirror 20M, and is composed of a convex lens having a positive power here. The rod lens 15 equalizes the illuminance of the light incident on the incident surface 15M. The positions of the incident surface 15M of the condenser lens 14 and the rod lens 15 are set so as to be closer to the light source portion than the second focal position of the elliptical mirror 20M.

That is, the distance A from the first focal position of the elliptical mirror 20M to the condenser lens 14 and the distance B to the rod lens incident surface 15M are shorter than the distance C to the second focal position. Further, the position of the rod lens incident surface 15M is determined so that the distance interval E between the condensing lens 14 (center) and the rod lens incident surface 15M is shorter than the focal length f of the condensing lens 14. The condensing angle θ of the condensing lens 14 is larger than the NA of the light emitted from the illumination optical system 11 (hereinafter referred to as the illumination NA). However, the focusing angle θ represents Arctan (lens diameter / distance from the focusing lens 14 to the rod lens 15).

The relay optical system 16 is an optical system that projects the light emitted from the rod lens emitting surface 15N onto the DMD incident surface 22P, and the rod lens emitting surface 15N and the DMD incident surface 22P are in a conjugate relationship with each other. Further, the relay optical system 16 includes an aperture diaphragm 16A that determines the NA (illumination NA) of the light emitted from the illumination optical system 11. The aperture diameter of the diaphragm 16A is set so that the projection area of the DMD incident surface 22P is expanded to an area equal to or larger than the area of the rod lens ejection surface 15N.

The optical filters 13A, 13B, and 13C are held by holding members (not shown) in this order from the light source side. The holding member is connected to a filter driving unit 17 that advances and retreats each optical filter in the direction orthogonal to the optical axis X. The operation of the filter driving unit 17 is controlled by the controller 30, and the insertion distance (that is, the amount of attenuation of the illumination light) of the optical filters 13A, 13B, and 13C with respect to the luminous flux on the optical path can be adjusted.

3A and 3B are diagrams showing the relationship between the insertion distance of the optical filter 13A and the apparent incident angle of the light incident on the optical filter.

Assuming that the angle of light rays passing through the center of the light flux portion blocked by the optical filter 13A is the apparent incident angle Θx, the apparent angle Θx changes according to the insertion distance of the optical filter 13A. FIG. 3A shows the case where the optical filter is inserted up to the position of 3/4 of the luminous flux, and FIG. 3B shows the case where the optical filter is inserted up to the position of 1/3 of the luminous flux.

The optical filter 13A, which is a dielectric multilayer interference filter, has an angle dependence. Therefore, when the apparent angle Θx of the light incident on the optical filter 13A changes, the spectral distribution of the light integrated (combined) by the rod lens 15 changes. In order to suppress the change in the spectral distribution of the illumination light, it is desirable that the angle of incidence Θa of the light on the optical filter 13A is as small as possible (close to perpendicular to the filter surface). However, the incident angle Θa represents the maximum angle formed by the light incident on the optical filter 13A with the optical axis X of the illumination optical system 11.

On the other hand, in order to increase the illumination NA of the illumination optical system 11, it is necessary to perform sufficient integration with the rod lens 15. Therefore, the condenser lens 14 is provided so that the incident angle Θa and the maximum incident angle Θb (see FIG. 2) formed by the optical axis X when light is incident on the rod lens 15 satisfy the relationship of Θa <Θb. ing. The optical filters 13B and 13C are also provided so as to satisfy the same conditions as the optical filters 13A.

The insertion direction (movement direction of the optical filter) Mf of each of the optical filters 13A to 13C corresponds to the direction opposite to the scanning direction at the time of exposure, that is, the direction equal to or close to the relative movement direction Mx (see FIG. 1) of the substrate W. doing. That is, when any of the optical filters 13A to 13C is inserted, the insertion direction Mf is determined so that the attenuation of the light intensity starts from the first side in the scanning direction of the exposure area.

When any of the optical filters 13A to 13C is inserted, a minute difference occurs in the illuminance distribution in the exposure area. Even in such a case, the moving direction Mf of the optical filter is along the relative moving direction Mx of the substrate W, so that the exposure amount is averaged by multiple exposures by the micromirrors that sequentially pass through predetermined locations, and the pattern is made uniform. It can be exposed and formed.

When the holding member moves to the optical path side and the optical filters 13A (13B, 13C) are inserted into the light flux on the optical path, a part of the light flux passes through the optical filters 13A (13B, 13C). A predetermined wavelength region (for example, 300 nm to 380 nm) of the light that has passed through the optical filter is attenuated with respect to the light intensity of the other wavelength region. As a result, the spectral distribution of the exposure light applied to the surface of the substrate W is adjusted.

FIG. 4 is a diagram showing a spectral distribution curve of light emitted from the light source unit 20.

As shown in FIG. 4, the discharge lamp 20D emits continuous spectral light including emission lines of g-line (436 nm), h-line (405 nm), and i-line (365 nm). The user controls the positions of the optical filters 13A to 13C of the wavelength adjustment mechanism 12 in order to correct the spectral distribution to be suitable for the photosensitive characteristics of the resist film and the like.

In adjusting the spectrum distribution, a correction table is created by measuring the relationship between the insertion distance of the optical filter and the amount of attenuation of the light intensity of a predetermined wavelength of the exposure light in advance, and the data is stored in the memory 32 in advance. There is. The controller 30 refers to the correction table of the memory 32, and moves the optical filters 13A, 13B, and 13C by the filter driving unit 17 so that the spectrum distribution is such that the reaction of the resist film by the irradiation of the exposure light is properly performed. ..

FIG. 5 is a diagram showing a spectral distribution when the optical filter 13A is inserted. Here, the optical filter 13A is inserted into the optical path to a predetermined distance. The other optical filters 13B and 13C are arranged outside the optical path. The spectral distribution SP is modified to the spectral distribution SP1 in which the light intensity is substantially halved in the range of approximately 350 to 400 nm in the short wavelength region.

FIG. 6 is a diagram showing a spectral distribution when the optical filter 13C is inserted. Here, the optical filter 13C is inserted into the optical path to a predetermined distance. The other optical filters 13A and 13B are arranged outside the optical path. The spectral distribution SP is modified to the spectral distribution SP2 in which the light intensity is approximately halved in the range of approximately 420 to 450 nm in the short wavelength region.

FIG. 7 is a diagram showing a spectral distribution when the optical filter 13B is inserted. Here, the optical filter 13B is inserted into the optical path to a predetermined distance. The other optical filters 13A and 13C are arranged outside the optical path. The spectral distribution SP is modified to the spectral distribution SP3 in which the light intensity is substantially halved in the range of approximately 390 to 425 nm in the short wavelength region.

Although FIGS. 5 to 7 show the spectral distribution when any of the optical filters 13A to 13C is inserted on the optical path, it is also possible to insert two or three optical filters on the optical path. The degree of reduction in light intensity is not limited to half, and the target optical filter may be inserted only by the insertion distance according to the desired amount of light intensity attenuation.

As described above, according to the present embodiment, in the exposure apparatus 1 provided with the light source unit 20 provided with the discharge lamp 20D and the elliptical mirror 20M, and the illumination optical system 11, the illumination optical system 11 is the optical filters 13A to 13C. It is composed of a condenser lens 14, a rod lens 15, and a relay optical system 16, and is arranged in this order from the light source side.

In the present embodiment, the condenser lens 14 is provided at a position sufficiently closer to the light source portion side than the second focal position of the elliptical mirror 20M, and the position of the incident surface 15M of the rod lens 15 is also sufficiently closer to the light source side than the second focal position. close. By arranging the condenser lens 14 on the rear side (ejection surface) side of the optical filters 13A to 13C, the incident angle Θa of the light incident on the optical filters 13A to 13C is reduced with respect to the optical axis X, and the optical filters 13A to 13A to 13C. Light can be incident at an angle substantially perpendicular to the incident surface of 13C. As a result, it is possible to suppress the occurrence of wavelength shift due to the difference in incident angle.

On the other hand, by condensing light with the condensing lens 14 and equalizing the illuminance with the rod lens 15, even if the optical filters 13A to 13C are inserted into the optical path, the change in the illumination NA of the illumination optical system 11 is suppressed. be able to. Therefore, the spectral distribution of light can be changed by the optical filters 13A to 13C without affecting the resolution.

Further, since the condensing angle θ of the condensing lens f is sufficiently larger than that of the illumination NA, the number of internal reflections of the light incident on the rod lens 15 increases, and the illuminance distribution unevenness does not occur. As a result, the resolution of the relay optical system 16 is not affected.

Further, in order to satisfy Θa <Θb, the light is integrated on the exit surface of the rod lens 15 regardless of the insertion distance of the optical filters 13A to 13C (regardless of the light state of the incident surface), and the illuminance distribution is uniform and uniform. It becomes the light distribution angle. By installing the aperture diaphragm 16A at the pupil position of the relay optical system 16, the illumination NA can be determined.

In the conventional configuration in which the fly-eye lens is arranged, the light is integrated on the irradiation surface, so that uneven shading (attenuation) at the pupil position on the fly-eye exit surface affects the illumination NA. However, according to the present embodiment in which the fly-eye lens is not used, since the NA is determined by the pupil surface after the light is sufficiently integrated, the illumination NA of the illumination optical system 11 is determined regardless of the insertion amount of the optical filter. It becomes possible to make it constant.

In the present embodiment, the optical filters 13A, 13B, and 13C are arranged in this order from the light source unit 20 toward the condenser lens 14, and are configured to be movable between the optical path and the outside of the optical path. As a result, it is not necessary to replace the filter, and it is possible to correspond to the spectral distribution that changes depending on the exposure environment.

Further, in the present embodiment, a filter having a relatively short wavelength range (attenuation wavelength) for reducing light intensity is arranged on the light source side of the filter having a relatively long attenuation wavelength. Thereby, deterioration of ultraviolet rays can be prevented.

For example, when the optical filters 13A and 13C are inserted on the optical path, the filters adopt 100% reflective filters, respectively, so that the light (i-line, g-line) reflected by the optical filters 13A and 13C is the light source unit 20. Proceed towards. Therefore, the reflected light (g line) of the optical filter 13C irradiates the optical filter 13A.

Ultraviolet rays cause deterioration of optical components in the long term, and shorter wavelengths have a greater influence on deterioration. The optical filter 13A reflects the i-line that has the greatest influence on deterioration, but since the optical filter is not arranged on the light source side of the optical filter 13A, deterioration of the optical filter can be prevented. Further, since the g-ray having a relatively long wavelength irradiates the optical filter 13A, the optical filter 13A is not so affected by the deterioration.

As described above, in the present embodiment, the predetermined wavelength region is attenuated by the plurality of optical filters 13A, 13B, 13C, but the number of optical filters may be one. Further, although a rod lens is used as the illuminance uniformizing means, a random bundle fiber in which a large number of optical fibers are bundled so that the emission positions are random may be used. Further, as the illuminance uniform optical system, a fly-eye lens may be provided instead of the rod lens. Further, a parabolic mirror may be used instead of the elliptical mirror, and a condensing mirror may be used instead of the condensing lens.

As the discharge lamp, a discharge lamp other than the above can be used, and the discharge lamp has a continuous spectrum distribution and emits g-line, h-line, and i-line in a continuous spectrum including an emission line. Applicable. Alternatively, a discharge lamp that emits continuous spectral light containing a plurality of other emission lines may be used.

In the above embodiments, an exposure apparatus that exposes a pattern to a substrate using a DMD (spatial light modulation element) has been described, but the present invention is similarly applied to an exposure apparatus that exposes a pattern to a substrate using a photomask. can do.

FIG. 8 is a block diagram of the exposure apparatus according to the second embodiment. The exposure apparatus 1'is configured as a projection exposure apparatus that projects pattern light onto the substrate W using a photomask 22'. FIG. 9 is a block diagram of the exposure apparatus according to the third embodiment. The exposure apparatus 1 "is configured as a contact exposure apparatus that projects pattern light onto the substrate W using a photomask 22". In each of the exposure devices 1'and 1 ", the illumination optical system 11 similar to that of the first embodiment is configured.

1 Exposure device 10 Exposure head 11 Illumination optical system 13A Optical filter 13B Optical filter 13C Optical filter 14 Condensing lens 15 Rod lens 16 Relay optical system 16A Aperture aperture 20 Light source 20D Discharge lamp 20M Elliptical mirror W substrate

Claims (11)

A light source that emits light with a continuous light intensity distribution, a light source unit with an elliptical mirror, and
It is provided with an illumination optical system in which the center of the light source is arranged near the first focal position of the elliptical mirror and the irradiation surface is illuminated by the light from the light source unit.
The illumination optical system
A condensing optical system that condenses light from the light source unit,
Light from the condensing optical system is incident to make the illuminance uniform, and an illuminance uniforming optical system composed of a rod lens or a random fiber bundle is used.
It is provided with an optical filter that is arranged on the light source side of the condensing optical system, is movable between the optical path and the outside of the optical path, and attenuates the light intensity in a predetermined wavelength region.
The exit surface of the illuminance uniforming optical system is arranged closer to the light source portion than the second focal position of the elliptical mirror .
An exposure apparatus characterized in that the optical filter is arranged in an optical path so that light from the light source unit is incident at an angle substantially perpendicular to the incident surface of the optical filter. The maximum incident angle Θa formed by the optical axis of the illumination optical system when light is incident on the optical filter is smaller than the maximum incident angle Θb formed by the optical axis when light is incident on the illuminance uniform optical system. The exposure apparatus according to claim 1. The exposure apparatus according to claim 1 or 2, wherein the focusing angle of the focusing optical system is larger than the NA of the illumination optical system. The exposure apparatus according to any one of claims 1 to 3, wherein the distance between the condensing optical system and the incident surface of the illuminance uniforming optical system is shorter than the focal length of the condensing optical system. .. A relay optical system that is arranged between the illuminance uniformizing optical system and the irradiation surface and projects an image of the emission surface of the illuminance uniforming optical system onto the irradiation surface is further provided.
The exposure apparatus according to any one of claims 1 to 4, wherein the relay optical system illuminates the irradiation surface at the same magnification or at a predetermined magnification with respect to the emission surface of the illuminance uniform optical system. .. The optical filter is composed of a plurality of optical filters that attenuate light in different wavelength regions.
The exposure apparatus according to any one of claims 1 to 5, further comprising a filter insertion amount adjusting unit for adjusting the insertion amount of the plurality of optical filters into the optical path. The exposure apparatus according to claim 6, wherein the optical filter having a relatively short attenuation wavelength among the plurality of optical filters is arranged closer to the light source portion than the optical filter having a relatively long attenuation wavelength. .. The exposure apparatus according to claim 6 or 7, wherein the plurality of optical filters are arranged from the light source side in ascending order of attenuation wavelength. The exposure apparatus according to any one of claims 1 to 8, wherein the illuminance uniforming optical system is composed of a rod lens. The discharge lamp emits light including g-line, h-line, and i-line.
The exposure apparatus according to any one of claims 1 to 9, wherein the optical filter attenuates light intensity in a wavelength region including at least one emission line of g-line, h-line, and i-line. A light source that emits light with a continuous light intensity distribution, a light source unit that includes a parabolic mirror, and a light source unit.
It is provided with an illumination optical system that illuminates the irradiation surface with the light from the light source unit.
The illumination optical system
A condensing optical system that condenses light from the light source unit,
An illuminance uniforming optical system in which light from the condensing optical system is incident to make the illuminance uniform,
An exposure device that is arranged closer to the light source portion than the condensing optical system, is movable between the optical path and the outside of the optical path, and is provided with an optical filter that attenuates the light intensity in a predetermined wavelength range. ..

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