TWI828831B - Exposure device - Google Patents

Abstract

The exposure device of the present invention includes: a projection optical system; an illumination optical system that supplies illumination light to the projection optical system; and a scanning stage that relatively scans the exposed substrate and the projection optical system in the scanning direction, and the scanning stage causes the exposed substrate to The illumination optical system or the projection optical system is scanned relative to the projection optical system to expose the substrate to be exposed by overlapping a plurality of scanning exposure fields formed by the projection optical system. The illumination optical system or the projection optical system has an illuminance changing member, and the illuminance changing member is as follows It is set that during exposure, the exposure amount of the non-overlapping portion exposed without overlapping on the exposed substrate is smaller than the exposure amount of the overlapping portion exposed without overlapping on the exposed substrate.

Description

Exposure device

The present invention relates to an exposure device.

As a device for exposing and transferring a pattern master on a mask to a large substrate, there is known a scanning type exposure in which the mask and the substrate are relatively scanned with respect to a projection optical system and exposed. device. There is also known an exposure device that expands the exposure field of view in the scanning direction (scanning direction) by scanning exposure, but in order to further expand the exposure field of view in the direction crossing the scanning direction (non-scanning direction), and The exposure areas are overlapped in the non-scanning direction to perform multiple scanning exposures.

Furthermore, a method is also known in which a plurality of projection optical systems are arranged in parallel in the non-scanning direction, and a part of the exposure field of view exposed by the plurality of projection optical systems is overlapped and exposed simultaneously, thereby exposing electronic circuits in one scan. Transferred to a substrate (for example, Patent Document 1).

[Prior art documents] [Patent Document]

Patent Document 1: Japanese Patent Application Publication No. 2016-54230

According to the first aspect, the exposure device includes: a projection optical system; an illumination light an optical system that supplies illumination light to the projection optical system; and a scanning stage that relatively scans the exposed substrate and the projection optical system along the scanning direction, and the scanning stage makes the exposed substrate relative to the The projection optical system relatively scans to expose the substrate to be exposed by overlapping a plurality of scanning exposure fields formed by the projection optical system, and the illumination optical system or the projection optical system has an illumination changing member, The illumination changing member is set so that, in the exposure, the amount of exposure in the overlapped portion is overlapped and exposed on the exposed substrate, so that the exposed substrate is exposed without overlapping. The exposure of the non-overlapping portion becomes smaller.

1:Light source

2: Elliptical reflector

3, 5: Bending reflector

4, 6: Relay lens

7: Optical fiber

8a~8e: Input lens

9a~9e: Light shielding member holding part

9c1: Slider

10a~10e: Light shielding member (illuminance changing member)

10c1, 10c2: light-shielding member

11a~11e: compound eye lens (optical integrator)

12a~12e: condenser lens

13, 24: Moving mirror

14, 25: Laser interferometer

15: Mask

16: Mask stage

17: Mask stage platform

19a, 19c, 19e, 19F: Projection optical system (first row of projection optical system)

19b, 19d, 19R: Projection optical system (second row projection optical system)

20: Middle image surface

21a~21e: Field of view aperture

21ao~21eo: The opening of the field of view aperture (opening)

22: Substrate (exposed substrate)

23: Position detection optical system

26: Illuminance sensor

27: Scanning stage (substrate stage)

28: Substrate carrier platform

71: The incident side of the optical fiber (incident side)

72a~72e: Exit side of optical fiber (exit side)

100:Exposure device

110: Lens unit

E, E2, E3: cumulative exposure

E1: The value of cumulative exposure

EE: effective photosensitivity

EE1, EE2: the value of the actual photosensitivity

ILa~ILe: illumination optical system

IPIc: area (area corresponding to exposure field of view)

IWs: Width (width) in the Y direction of the portion corresponding to the center area of the exposure field of view in the exposure field of view corresponding area

IXa~IXe: Optical axis (optical axis) of the illumination optical system

MIa~MIe: lighting area

Oa~Od: part (overlapping part)

PIa~PIe: exposure field of view

PIac~PIec: central area

PIal~PIel: left end area

PIar~PIer: right end area

PX: The pitch (pitch) of the arrangement of the lens units in the X direction

PXa~PXe: Optical axis (optical axis) of the projection optical system

Sa~Se: non-overlapping part (part)

SIa~SIe: scanning exposure field of view

W1, W2: Width (width) of the light shielding member in the Y direction

Wo: The length (width) of the left end area and the right end area in the Y direction

Ws: length (width) of the central area in the Y direction

X, Y, Z: direction

FIG. 1 is a side view showing the structure of the exposure device according to the first embodiment.

FIG. 2 is a perspective view showing part of the exposure device according to the first embodiment.

3 is an enlarged perspective view showing the exposure device of the first embodiment from a fly-eye lens to a mask.

4 is a diagram showing the relationship between the visual field on the mask and the visual field on the substrate of the exposure device according to the first embodiment. Figure 4 (a1), Figure 4 (a2) and Figure 4 (a3) respectively show the field of view on the mask of the projection optical system 19c in Figure 1, the field of view aperture in the projection optical system, and the field of view on the substrate. 4 (b1), (b2) and (b3) respectively show the field of view on the mask of the projection optical system 19b in FIG. 1, the field of view aperture in the projection optical system, and the substrate. A diagram of the field of view.

FIG. 5 shows scanning exposure of a substrate using the exposure apparatus according to the first embodiment. This is an example of the exposure energy (energy) irradiated onto the substrate and the effective light exposure amount of the photosensitive material. FIG. 5(a) is a diagram showing the exposure field of view on the substrate of each projection optical system. FIG. 5(b) is a diagram showing the exposure area formed on the substrate 22. FIG. 5(c) is a diagram showing the irradiation area. (d) of FIG. 5 is a graph showing an example of the cumulative exposure amount on the substrate. FIG. 5(d) is a graph showing an example of the effective exposure amount of the photosensitive material.

6 is a view of a fly-eye lens, a light-shielding member, and a light-shielding member holding portion of the exposure device according to the first embodiment as viewed from the light source side.

7 is a diagram showing an example of the exposure energy irradiated onto the substrate and the effective light exposure amount of the photosensitive material when the exposure apparatus according to the first embodiment performs scanning exposure on the substrate. FIG. 7(a) is a diagram showing the exposure field of view on the substrate of each projection optical system, FIG. 7(b) is a diagram showing an example of the cumulative exposure amount irradiated on the substrate, and FIG. 7(c) is a diagram showing A graph showing an example of the effective light sensitivity of a photosensitive material.

(First embodiment of exposure device)

FIG. 1 is a side view showing the exposure device 100 according to the first embodiment. As will be described later, the exposure device 100 includes five projection optical systems 19a to 19e. FIG. 1 shows only two of them, namely, the projection optical system 19a and the projection optical system 19b.

The projection optical systems 19a to 19e are optical systems that form an erect image with a projection magnification (horizontal magnification) + 1 times, and expose and transfer the pattern drawn on the mask 15 to the photosensitive pattern formed on the upper surface of the substrate 22 Material.

The substrate 22 passes through a substrate holder (not shown) via the substrate stage 27 (holder) keep. The substrate stage 27 is scanned in the X direction on the substrate stage platform 28 by a linear motor (not shown) and can move in the Y direction. The position of the substrate stage 27 in the X direction is measured by a laser interferometer 25 via the position of the moving mirror 24 attached to the substrate stage 27 . Similarly, the position of the substrate stage 27 in the Y direction is also measured by a laser interferometer (not shown).

The position detection optical system 23 detects the position of existing patterns such as alignment marks formed on the substrate 22 .

The mask 15 is held by the mask stage 16 . The mask stage 16 is scanned in the X direction on the mask stage platform 17 by a linear motor (not shown) and can move in the Y direction. The X-direction position of the mask stage 16 is measured by the laser interferometer 14 via the position of the moving mirror 13 installed on the mask stage 16 . Similarly, the position of the mask stage 16 in the Y direction is also measured by a laser interferometer (not shown).

A control system (not shown) controls a linear motor (not shown) and the like based on the measurement values of the laser interferometer 14 and the laser interferometer 25 to control the XY positions of the mask stage 16 and the substrate stage 27 . When the mask pattern is exposed to the substrate 22, the control system (not shown) causes the mask 15 and the substrate 22 to maintain the imaging relationship formed by the projection optical systems 19a to 19e relative to the projection optical systems 19a to 19e. The projection optical system 19e relatively scans in the X direction at substantially the same speed.

In this specification, the direction in which the substrate 22 is scanned (X direction) during exposure is also referred to as the "scanning direction." In addition, the direction included in the plane of the substrate 22 and orthogonal to the X direction (Y direction) is also called a “non-scanning direction”. The Z direction is a direction orthogonal to the X direction and the Y direction.

In addition, in FIG. 1 and the following figures, the X direction, Y direction, and Z direction are indicated by arrows, and the direction indicated by the arrows is the + direction.

FIG. 2 is a perspective view showing a portion from the downstream portion of the illumination optical systems ILa to ILe to the substrate 22 of the exposure apparatus 100 according to the first embodiment. Hereinafter, the description will be continued with reference to FIG. 2 as well.

As shown in FIG. 2 , three of the five projection optical systems 19 a to 19 e , namely the projection optical system 19 a , the projection optical system 19 c , and the projection optical system 19 e (hereinafter, are also collectively referred to as or individually referred to as "first The line projection optical systems 19F") are arranged side by side in the Y direction. Moreover, the two projection optical systems 19b and 19d (hereinafter also collectively or individually referred to as the "second row projection optical system 19R") are arranged in the Y direction and are arranged farther than the first row projection optical system. 19F is closer to the +X side.

Each projection optical system of the first row projection optical system 19F is arranged with its optical axis separated by a predetermined interval in the Y direction. Each optical system of the second row projection optical system 19R is also arranged similarly to the first row projection optical system 19F. Moreover, the projection optical system 19b is arranged so that the position of the optical axis in the Y direction coincides with the approximate center of a straight line connecting the optical axes of the projection optical system 19a and the projection optical system 19c. In addition, the projection optical system 19d is also arranged similarly to the projection optical system 19b.

The exposure apparatus 100 of the first embodiment includes a plurality of illumination optical systems ILa to ILe corresponding to each of the projection optical systems 19a to 19e. As an example, as shown in FIG. 1 , the illumination optical system ILa corresponding to the projection optical system 19a includes an input lens 8a, a fly-eye lens 11a, and a condenser lens along the optical axis IXa. )12a. The other illumination optical systems ILb to ILe also include input lenses 8b to 8e, fly eye lenses 11b to fly eye lenses 11e, and condenser lenses 12b to 12e. In addition, as mentioned above, in FIG. 2 , only the fly-eye lenses 11a to 11e and the condenser lenses 12a to 12e in each of the illumination optical systems ILa to ILe are shown.

Furthermore, in the side view of FIG. 1 , the projection optical systems 19 c to 19 e are not shown because they coincide with the positions of the projection optical system 19 a or 19 b in the X direction. Similarly, the illumination optical systems ILc to ILe are not shown because they coincide with the positions of the illumination optical system ILa or ILb in the X direction.

Illumination light supplied from a light source 1 such as a lamp passes through an elliptical mirror 2, a flexural reflector 3, a relay lens 4, a flexural reflector 5, a relay lens 6, and an optical fiber. Light guide optical systems such as fiber)7 are supplied to each of the illumination optical systems ILa to ILe. The optical fiber 7 branches the illumination light incident on one incident side 71 into approximately equal parts, and emits the illumination light toward the five emission sides 72a to 72e. The illumination lights respectively emitted from the five emission sides 72a to 72e of the optical fiber 7 are incident on the input lenses 8a to 8e in the respective illumination optical systems ILa to ILe. Then, the illumination light further passes through the fly-eye lenses 11a to 11e and the condenser lenses 12a to 12e, and is irradiated toward the illumination areas MIa to MIe on the mask 15.

FIG. 3 is an enlarged view of the fly-eye lens 11 c and the condenser lens 12 c included in the illumination optical system ILc, and the illumination area MIc on the mask 15 as an example. three-dimensional view.

In the fly-eye lens 11c, a plurality of lens elements 110 are formed in an array in the X direction and the Y direction. The lens elements 110 have a rectangular cross-sectional shape (XY) that is similar to the illumination area Mic and is long in the Y direction. shape within the plane). Due to the optical system including each lens unit 110 and the condenser lens 12c, the incident surface of each lens unit 110 (the upper surface in FIG. 3, that is, the surface on the +Z side) forms an optical system with respect to the illumination area MIc on the mask 15. conjugate surface. Therefore, it is also a conjugate surface with respect to the exposure field of view PIc on the substrate 22 . The illumination light irradiated toward the incident surface of each lens unit 110 is irradiated so as to overlap the illumination area MIc on the mask 15 . Thereby, the illumination intensity of the illumination light in the illumination area MIc is substantially uniform.

The configurations of the other illumination optical systems ILa to ILe except for the illumination optical system ILc are also the same as those shown in FIG. 3 .

The fly-eye lenses 11a to 11e are an example of an optical integrator that irradiates illumination light to the illumination areas MIa to MIe in an overlapping manner.

Each of the projection optical systems 19a to 19e includes, for example, a secondary imaging optical system in order to form an image of an erect image. In this case, by the optical system constituting the upper half of each projection optical system 19a to 19e, in the direction (Z The intermediate image plane 20 near the middle of the direction) forms an intermediate image of the pattern of the mask 15 . The intermediate image is formed again on the substrate by the optical system constituting the lower half of each projection optical system 19a to 19e. An image of the pattern of the mask 15 is formed on 22 .

Since the intermediate image plane 20 is conjugate with the substrate 22, the visual field aperture 21a to the visual field aperture 21e are respectively disposed on the intermediate image plane 20 in each of the projection optical systems 19a to 19e, whereby the projections on the substrate 22 can be specified. The exposure fields PIa to PIe formed by the optical systems 19a to the projection optical systems 19e.

FIG. 4 is a diagram showing the relationship between the illumination areas MIa to MIe on the mask 15, the visual field apertures 21a to the visual field apertures 21e, and the exposure visual fields PIa to PIe.

FIG. 4(a1) is a diagram showing the illumination area MIc on the mask 15 corresponding to the projection optical system 19c. The illumination area MIc forms a rectangle similar to the cross-sectional shape of the lens unit 110 of the fly-eye lens 11c.

(a2) of FIG. 4 is a diagram showing the visual field aperture 21c in the projection optical system 19c and the illumination light MIc2 irradiated at the visual field aperture 21c. The field of view aperture 21c is illuminated with illumination light MIc2, which is an intermediate image of the illumination area MIc on the mask 15 and is shown by a dotted line. Among the illumination light MIc2, the illumination light that irradiates the light-shielding portion (the portion indicated by hatched lines) of the visual field aperture 21c is blocked by the visual field aperture 21c. On the other hand, the illumination light transmitted through the opening 21co of the field of view aperture 21c is re-imaged on the substrate 22 by the optical system constituting the lower half of the projection optical system 19c, and an exposure field of view PIc is formed on the substrate 22.

(a3) of FIG. 4 is a diagram showing the exposure field of view PIc on the substrate 22.

As an example, when the projection optical systems 19c to 19e include a fully refractive optical system, the intermediate image, that is, the illumination light MIc2 is relative to the illumination area MIc. An inverted image (the X and Y directions of the image are both reversed, rather than a mirrored image), and the exposure field of view PIc forms an inverted image relative to the field of view aperture 21c. Therefore, as shown in FIGS. 4(a2) and 4(a3) , the shape of the opening 21co of the field of view aperture 21c and the shape of the exposure field of view PIc match each other by rotating 180 degrees around the Z axis.

As an example, the exposure field of view PIc is a trapezoid in which the short side of the two sides parallel to the Y direction is located on the +X side and the long side is located on the -X side. Here, a rectangular area in the exposure field of view PIc surrounded by all the short sides on the +X side and part of the long sides on the -X side is called a central area PIcc. On the other hand, the end of the exposure field of view PIc in the +Y direction that is not included in the central area PIcc is called a left end area PIcl, and the end of the exposure field of view PIc in the -Y direction that is not included in the central area PIcc is called a left end area PIcl. Right end area PIcr.

The length (width) of the center area PIcc in the Y direction is called width Ws, and the lengths (widths) of the left end area PIcl and the right end area PIcr in the Y direction are equal, which is called width Wo.

On the other hand, FIGS. 4(b1) to 4(b3) are diagrams respectively showing the illumination area MIb, the visual field aperture 21b, and the exposure visual field PIb on the mask 15 corresponding to the projection optical system 19b. As shown in FIG. 4(b2) , in the projection optical system 19b, the shape of the opening 21bo of the visual field aperture 21b is a shape in which the shape of the opening 21co of the visual field aperture 21c of the projection optical system 19c is inverted in the X direction. As a result, as shown in (b3) of FIG. 4 , the shape of the exposure field of view PIb of the projection optical system 19b is the shape of the exposure field of view PIc of the projection optical system 19c. A shape that is inverted along the X direction.

Like the exposure field of view PIc described above, in the exposure field of view PIb, a rectangular area surrounded by all the short sides on the -X side and part of the long sides on the +X side is also called the central area PIbc. The end of the exposure field of view PIb in the +Y direction that is not included in the central area PIbc is called the left end area PIbl, and the end of the exposure field of view PIb in the -Y direction that is not included in the central area PIbc is called the right end area PIbr.

(a) of FIG. 5 is a diagram showing the respective exposure fields PIa to PIe of the five projection optical systems 19a to 19e on the substrate 22. The exposure fields PIa and PIe of the first row projection optical system 19F, that is, the projection optical systems 19a and 19e, are the two sides parallel to the Y direction, similarly to the exposure field PIc of the projection optical system 19c. A trapezoid with the short side on the +X side and the long side on the -X side. On the other hand, the exposure field of view PId of the second row projection optical system 19R, that is, the projection optical system 19d, is such that the short side of the two sides parallel to the Y direction is located at -X, similarly to the exposure field of view PIb of the projection optical system 19b. A trapezoid with the side and long side on the +X side.

For the exposure fields PIa, PId, and PIe of the projection optical systems 19a, 19d, and 19e, similarly to the exposure fields PIb and PIc described above, the center area PIac, the center area PIac, and the center area PIac can be defined. The area PIdc, the center area PIec, the left end area PIal, the left end area PIdl, the left end area PIel, the right end area PIar, the right end area PIdr, and the right end area PIer. However, the exposure field of view PIa arranged at the end in the -Y direction blocks the illumination light by the field of view aperture 21a so that the end in the -Y direction is parallel to the X direction, so it is not There is a right end area PIar. In addition, since the exposure field PIe arranged at the end in the +Y direction blocks the illumination light by the field of view aperture 21e so that the end in the +Y direction is parallel to the X direction, there is no left end area PIel. Furthermore, the shapes of the visual field aperture 21a and the visual field aperture 21e may be different from the shape of the visual field aperture 21c, or other members may be used to block the illumination light so that there is no right end area PIar in the exposure field of view PIa.

The Y-direction length of each center area PIac~PIec of each exposure field of view PIa~PIe is equal to the width Ws. The lengths of the left end area PIal~left end area PIdl and the right end area PIbr~right end area PIer are all equal to the width Wo. . Moreover, among the two exposure fields of view PIa to PIe that are adjacent in the Y direction, the positions of the adjacent left end areas PIal to PIdl and the right end areas PIbr to PIer in the Y direction are consistent.

This shape of each exposure field of view PIa to exposure field of view PIe is achieved by setting the arrangement positions of the projection optical systems 19a to 19e and the shapes and positions of the openings 21ao to 21eo of the visual field apertures 21a to 21e. and location settings.

(b) of FIG. 5 shows the exposure formed on the substrate 22 when the substrate 22 is scanned in the X direction by the substrate stage and exposed by the exposure field of view PIa to the exposure field of view PIe shown in (a) of FIG. 5 . Area map. The scanning exposure field SIa to the scanning exposure field SIe exposed by the respective exposure fields PIa to PIe by scanning exposure are formed on the substrate 22 . In FIG. 5(b) , the first row projection optical system 19a, the first row projection optical system 19c, and the first row projection optical system 19a are represented by a two-dot chain line. The scanning exposure field of view SIa, the scanning exposure field of view SIc, and the scanning exposure field of view SIe formed by the optical system 19e are represented by a dotted chain line, and the scanning exposure field of view SIb and the scanning field formed by the second row projection optical system 19b and 19d are represented by a dotted chain line. Exposure field SId.

The scanning exposure fields SIa to SIe are the exposure fields PIa to PIe that are extended in the X direction by scanning exposure in the X direction. The Y-direction (non-scanning direction) end portions of each scanning exposure field SIa to SIe overlap with the non-scanning direction end portions of other adjacent scanning exposure fields SIa to SIe. For example, the exposure area formed by the left end area PIal coincides with the exposure area formed by the right end area PIbr. Since the same applies to other exposure areas, description is omitted.

(c) of FIG. 5 is a graph showing the cumulative exposure amount E exposed on the substrate 22 by scanning exposure in the X direction. The vertical axis of the chart is the cumulative exposure, and the horizontal axis is the coordinate in the Y direction. As shown in (a) of FIG. 5 , since the cumulative values of the exposure fields PIa to PIe in the X direction are equal in each minute interval in the Y direction, and the exposure field PIa is affected by the action of the fly-eye lens 11 or the like. ~The illumination within the exposure field of view PIe is uniform, so the cumulative exposure amount E on the substrate 22 is a fixed value E1.

That is, the cumulative exposure amount E in the portion Sa to Se exposed by one of the scanning exposure fields SIa to the scanning exposure field SIe in the Y direction (hereinafter also referred to as a "non-overlapping portion"), and the cumulative exposure amount E in each scanning exposure field of view SIe The cumulative exposure amounts E of the two overlapped and exposed portions Oa to Od of the scanning exposure fields SIe (hereinafter also referred to as "overlapping portions") are equal to each other because the value of the cumulative exposure amounts E is E1.

In photosensitive materials such as photoresists used in the manufacturing steps of electronic devices, the effective sensitive light amount (hereinafter also referred to as "effective light sensitive amount") is directly proportional to the cumulative exposure amount. That is, if the cumulative exposure amount is the same, the effective light exposure amount of the photosensitive material does not change even if the exposure is performed continuously in time or when the exposure is performed in multiple stages in time.

Therefore, the effective amount of light exposure to the photosensitive material also becomes a fixed value.

However, when a part of a photosensitive material is exposed continuously in time, and when the exposure is divided into multiple stages in time, even if the cumulative exposure amount is the same, the effective light exposure amount of the photosensitive material changes. Specifically, when exposure is performed by dividing the exposure time into a plurality of steps, the effective light exposure amount is lower than when the exposure time is continuously performed.

FIG. 5(d) shows that for such a part of the photosensitive material (hereinafter also referred to as "non-additive photosensitive material"), the exposure field of view PIa to the exposure field of view PIe shown in FIG. 5(a) are used in the X direction. A chart of the effective exposure EE of non-additive photosensitive materials during scanning exposure.

The overlapping portions Oa to Od that are overlappingly exposed by the two scanning exposure fields SIa to the scanning exposure fields SIe are first exposed by the first row projection optical system 19a, the first row projection optical system 19c, and the first row projection optical system. 19e is exposed, and is subsequently exposed by the second row projection optical system 19b and the second row projection optical system 19d, so the exposure is performed in a time-divided manner. In other words, the overlapping portions Oa to Od are exposed discretely in time. Therefore, with respect to the non-overlapping portions Sa to non-overlapping portions Sa to which each scanning exposure field of view SIa to scanning exposure field of view SIe are exposed without being divided in time, The effective light sensitivity EE of the portion Se and the effective light sensitivity EE of the overlapping portions Oa to Od decrease. Specifically, the value of the effective photoreceptor amount EE of the non-overlapping portions Sa to Se is EE1, while the value of the effective photoreceptor amount EE of the overlapping portions Oa to Od is smaller than EE1.

As a result, when a non-additive photosensitive material is used for exposure transfer of a pattern, the actual light exposure amount EE is different in the overlapping portion Oa to the overlapping portion Od and the non-overlapping portion Sa to the non-overlapping portion Se. Variations in line width or thickness of printed patterns.

Therefore, in the exposure device 100 of the first embodiment, on the incident surface side of the fly-eye lenses 11a to 11e of the illumination optical systems ILa to ILe, respectively, that is, the input lenses 8a to 8e and the fly-eye lenses 11a to Light-shielding members 10a to 10e are provided at positions between the fly-eye lenses 11e and in the vicinity of the incident surfaces of the fly-eye lenses 11a to 11e. Furthermore, the light-shielding members 10a to 10e are arranged in directions substantially orthogonal to the optical axes IXa to IXe of the respective illumination optical systems ILa to ILe via the light-shielding member holding portions 9a to 9e, that is, Free movement in the X direction is maintained.

FIG. 6 is a view of the fly-eye lens 11c, the light-shielding member 10c, and the light-shielding member holding portion 9c provided in the illumination optical system ILc as viewed from the input lens 8c side. Hereinafter, the light shielding member 10c and the light shielding member holding portion 9c provided in the illumination optical system ILc will be described with reference to FIG. 6 . However, the light shielding members 10a to 10e provided in the other illumination optical systems ILa to ILe, The same applies to the light-shielding member holding portion 9a to the light-shielding member holding portion 9e.

The fly-eye lens 11c has a plurality of lens blocks arranged in the Y direction. The lens block has a plurality of rectangular lens units 110 arranged in the X direction and having a long cross-section in the Y direction. Since each lens unit 110 is a conjugate surface with respect to the exposure field of view PIc formed on the substrate 22, in FIG. 6, in each lens unit 110, a dotted line indicates an area corresponding to the exposure field of view PIc (exposure field of view corresponding area) )IPIc. The width in the Y direction of the portion of the exposure field of view corresponding region IPIc corresponding to the center area PIcc of the exposure field of view PIc is the width IWs.

The two light-shielding members 10c1 and 10c2 constituting the light-shielding member 10c are arranged on the + of one or more lens units 110 arranged on the -X direction side of the lens block with respect to two of the lens blocks. Near the Z side. The width W1 and the width W2 of the light shielding member 10c1 and the light shielding member 10c2 in the Y direction are substantially equal to the width IWs described above.

The light-shielding members 10c1 and 10c2 are held by a slider 9c1 which is a part of the light-shielding member holding part 9c. The slider 9c1 is freely movable in the X direction with respect to the body of the light-shielding member holding part 9c by a control system not shown. . The relative positional relationship between the slider 9c1 and the main body of the light-shielding member holding part 9c is measured by an encoder or the like.

The light-shielding member holding part 9c moves the light-shielding members 10c1 and 10c2 in the X direction, thereby blocking part of the lens unit 110 from light by the light-shielding members 10c1 and 10c2. As mentioned above, since the widths W1 and W2 of the light-shielding members 10c1 and 10c2 in the Y direction are substantially equal to the width IWs, the light-shielding members 10c1 and 10c2 can be directed from a portion of the lens unit 110 toward the substrate 22 The light irradiated by the central area PIcc in the exposure field of view PIc is blocked. Furthermore, By controlling the slider 9c1, the number of lens units 110 blocked by the light shielding member 10c1 and the light shielding member 10c2, and the ratio of the light blocked portion in one lens unit 110 can be changed. Thereby, the illuminance of the central area PIcc in the exposure field of view PIc can be substantially continuously and variably reduced relative to the illuminance of the left end area PIcl and the right end area PIcr.

Therefore, the light shielding member 10 c can be interpreted as an illuminance changing member that reduces the cumulative exposure amount toward the non-overlapping portion on the substrate 22 relative to the cumulative exposure amount toward the overlapping portion.

The light-shielding member 10c may be a metal thin plate or a light-shielding film formed by a light-shielding member on a transparent glass plate. The light-shielding member 10c is not limited to one that completely blocks the illumination light like a filter, but may be a member that blocks and transmits only a part of the illumination light. That is, the light shielding member 10c only needs to be an illumination changing member for changing the illumination.

The light-shielding members 10a to 10e and the light-shielding member holding portions 9a to 9e included in other illumination optical systems ILa to ILe are also different from the light-shielding member 10c and the light-shielding member holding portion 9c. The construction is the same.

7 is a diagram illustrating the results of exposure transfer of a pattern using a non-additive photosensitive material in the exposure apparatus 100 of the first embodiment including the light-shielding members 10a to 10e. FIG. 7(a) shows each exposure field of view PIa to exposure field of view PIe on the substrate 22, similarly to FIG. 5(a). Like FIG. 5(c) , FIG. 7( b ) is a graph showing the cumulative exposure amount E exposed on the substrate 22 by scanning exposure in the X direction.

In the case shown in (b) of FIG. 7 , the light shielding members 10a to 10e The light-shielding member holding portions 9a to 9e are inserted into the incident planes of the fly-eye lenses 11a to 11e. Therefore, compared with the cumulative exposure amount E3 of the overlapping portion Oa to the overlapping portion Od that is overlapped and exposed by two of the scanning exposure fields SIa to SIe, The cumulative exposure amount E2 of the non-overlapping portions Sa to Se is small.

FIG. 7(c) is a graph showing the effective photosensitive amount EE produced by the non-additive photosensitive material based on the cumulative exposure shown in FIG. 7(b). The cumulative exposure amount E2 of the non-overlapping portions Sa to Se that are exposed without being divided in time is compared with the cumulative exposure amount E3 of the overlapping portions Oa to Od that are exposed in time and are divided in time. By reducing, the characteristics of the non-additive photosensitive material can be offset, thereby setting the effective photosensitive amount EE to a roughly fixed value EE2.

Thereby, even when a non-additive photosensitive material is used for exposure transfer of a pattern, it is possible to prevent the overlapping portions Oa to Od from overlapping the scanning exposure fields SIa to the scanning exposure fields SIe, and the non-overlapping portions Sa. ~Changes in line width or thickness of the transferred pattern between non-overlapping portions Se.

Since the light-shielding member 10c is disposed at a predetermined distance away from the incident surface of the fly-eye lens 11c in the Z direction, the XY-direction edges of the light-shielding member 10c are blurredly projected on the incident surface of the fly-eye lens 11c. In other words, how far away from the incident surface of the fly-eye lens 11 c in the Z direction the light shielding member 10 c is appropriately arranged can be based on a parameter that determines the amount of penumbral blur at the edge of the light shielding member 10 c on the substrate 22 , that is, The horizontal magnification between the incident surface of the fly-eye lens 11c and the substrate 22 is determined by the number of openings of the illumination light in the incident surface of the fly-eye lens 11c. Certainly. Furthermore, it can also be determined by adding the width of the overlapping portion Oa to the overlapping portion Od on the substrate 22 in the Y direction. Furthermore, the light-shielding member holding portion 9a to the light-shielding member holding portion 9e may have a structure in which the Z-direction positions of the light-shielding members 10a to 10e with respect to the incident surfaces of the fly-eye lenses 11a to 11e can be changed. , that is, the distance between the light-shielding members 10a to 10e and the fly-eye lenses 11a to 11e in the Z direction can be changed.

As an example, let the width of the overlapping portion Oa to the overlapping portion Od in the Y direction be DW, let the lateral magnification of the substrate 22 with respect to the incident surface of the fly-eye lens 11 c be β, and let the illumination light in the incident surface of the fly-eye lens 11 c be When the number of openings is NA, the distance D in the Z direction from the light-shielding member 10c to the incident surface of the fly-eye lens 11c can be set to 0≦D≦1.2×DW/(β·NA)…(1).

When the distance D satisfies the equation (1), the influence of the exposure change (uneven exposure) on the substrate 22 caused by the edge of the light shielding member 10c can be further reduced, and the overlapping portion Oa to the overlapping portion Od can be prevented. The cumulative exposure is too low.

Furthermore, the relationship between the effective photosensitive amount and the cumulative exposure amount for the time-divided exposure of the non-additive photosensitive material differs among various non-additive photosensitive materials. Therefore, before actual exposure of a specific non-additive photosensitive material, for example, trial exposure can be carried out under various conditions in which the insertion amount (position in the X direction) of the light shielding member 10c is set to several different stages, that is, changed. A trial exposure is performed based on the number of lens units 110 that are blocked by the light shielding member 10c, and the optimal insertion amount is determined based on the results.

In addition, when determining the insertion amount of the light shielding member 10c, it is possible to use the The illumination sensor 26 on the stage 27 determines the illumination while measuring the illumination of the central area PIcc within the exposure field of view PIc.

Furthermore, the +X-direction ends of the two light-shielding members 10c1 and 10c2 constituting the light-shielding member 10c shown in FIG. 6 are respectively shifted by only the pitch of the X-direction arrangement of the lens units 110 of the fly-eye lens 11c. Half of PX. As described above, each lens unit 110 has the exposure field corresponding area IPIc corresponding to the exposure field of view PIc. However, the exposure field corresponding area IPIc does not extend over the entire surface of the lens unit 110 in the X direction. That is, both end portions of the lens unit 110 in the X direction do not correspond to the exposure field of view PIc on the substrate 22 but are projected onto the field of view aperture 21c in the projection optical system 19c and are blocked by the field of view aperture 21c.

Therefore, when the +X-direction ends of the light-shielding members 10c1 and 10c2 are located near both ends of the lens unit 110 in the X-direction, even if the light-shielding members 10c1 and 10c2 are moved in the X-direction, they cannot The accumulated exposure amount on the substrate 22 is changed.

Therefore, in the first embodiment, the ends in the +X direction of each of the two light shielding members 10cl and 10c2 are shifted by only half the pitch PX of the arrangement of the lens units 110 in the X direction.

With this arrangement, when the +X direction end of one of the two light shielding members 10c1 and 10c2 is located near both ends of the lens unit 110 in the X direction, the +X direction end of the other one of the two light shielding members 10c1 and 10c2 The end portion is arranged near the center of the lens unit 110 in the X direction. Therefore, by moving the two light shielding members 10c1 and 10c2 together in the X direction, the cumulative exposure amount on the substrate 22 can always be changed. Furthermore, The lengths of the two light shielding members 10c1 and 10c2 in the X direction may be equal to each other. In this case, it is preferable to adopt a structure in which the light-shielding member 10c1 and the light-shielding member 10c2 are independently moved in the X direction. Thereby, the amount of light shielding can be made different for each lens unit 110 .

Furthermore, the light shielding members 10c1 and 10c2 are not limited to the two mentioned above, and may also be three or more, as long as they are arranged in different lens blocks. Also in this case, it is preferable that if the number of light-shielding members is m (m is a natural number of 2 or more), then the +X-direction end of each light-shielding member is set to be offset by only Shift PX/m.

Furthermore, the light shielding member 10c is arranged at a position separated by a predetermined distance from the incident surface of the fly-eye lens 11c in the Z direction, but it is not limited to this. The light shielding member 10c only needs to be provided on the incident surface of the fly-eye lens 11c, that is, at a position that is the conjugate surface of the substrate. In this case, as long as the shape (width) of the light-shielding member 10c changes in the Y-direction according to the position in the X-direction, or like a filter whose transmittance changes according to the location, the light-shielding rate of the illuminating light depends on the position in the Y-direction. But it can be changed continuously. If the light shielding member 10c completely blocks the illumination light, the ratio of the cumulative exposure amount of the overlapping portions Oa to Od to the cumulative exposure amount of the non-overlapping portions Sa to Se may discontinuously change. This can be prevented. This situation.

(Modification)

In the above first embodiment, it is assumed that there are five projection optical systems 19a to 19e. However, the number of projection optical systems is not limited to five, and may be any number such as three or eight.

Furthermore, in the above first embodiment, there are a plurality of projection optical systems 19a to 19e, and a plurality of scanning exposure fields SIa to scanning exposure formed by each projection optical system are performed by scanning in the X direction once. The fields of view SIe overlap with each other in the Y direction.

However, the projection optical system may be one, and the substrate 22 and the mask 15 may be scanned and exposed in the The exposure fields of view overlap each other in the Y direction. In this case, it is also desirable that the illumination optical system corresponding to one projection optical system has the same configuration as the illumination optical systems ILa to ILe.

Furthermore, a device having a plurality of projection optical systems 19a to 19e like the first embodiment can expose a larger area on the substrate 22 with one scanning exposure, and has excellent processing capabilities.

In the above first embodiment, the plurality of projection optical systems 19a to 19e include a total refractive optical system, but are not limited thereto, and a catadioptric optical system or a total reflection optical system may also be used.

Furthermore, in the above first embodiment, the shapes of the exposure fields PIa to PIe are trapezoidal. However, they are not limited to trapezoids. For example, the shape of the portion corresponding to the center portion may be a circle. The arc includes the right end area and the left end area of the triangle at both ends of the arc.

In the above embodiment, the optical axes PXa to PXe of the projection optical systems 19a to 19e and the illumination optical systems ILa to the illumination light The optical axes IXa to IXe of the optical system ILe are basically set parallel to the Z direction. However, in the case of using a flexural mirror in any optical system, the direction of the optical axis is not parallel to the Z direction.

In addition, when a bending mirror is used in any optical system, the moving direction of the light shielding members 10 a to 10 e is also a direction different from the scanning direction (X direction) of the substrate 22 . However, in this case, the light shielding members 10a to 10e only need to optically correspond to the scanning direction of the substrate 22 based on the conjugate relationship between the substrate 22 including the flexural mirror and the fly eye lens 11a to the fly eye lens 11e. can move freely in the direction.

Furthermore, in the above embodiment, each of the projection optical systems 19a to 19e has two rows of optical systems, the first row projection optical system 19F and the second row projection optical system 19R, arranged in the X direction. However, This is not limited to two rows, and more than three rows of optical systems can also be configured in the X direction.

As an optical integrator, a rod integrator can be used instead of the aforementioned fly-eye lens 11 . When a rod integrator is used, the conjugate surface of the substrate 22 and the mask 15 becomes the exit side of the rod integrator (the mask 15 side), so the light shielding member 10 is also disposed on the exit side of the rod integrator. nearby. Furthermore, the vicinity of the X-side end of the emission surface of the rod-shaped integrator is partially shielded from light.

Instead of arranging the light shielding members 10a to 10e in the illumination optical systems ILa to ILe, they may be arranged near the intermediate image plane 20 of the projection optical systems 19a to 19e. In this case, the light shielding member is also configured near the intermediate image plane 20 and will be connected to the exposure field of view PIa to the exposure field of view PIe. The corresponding parts of the central area PIac ~ the central area PIec are shaded.

Instead of arranging the field of view aperture 21a to the field of view aperture 21e in the projection optical system 19a to 19e, an intermediate image plane (the conjugate plane with respect to the mask 15) may be provided in the illumination optical system ILa to ILe. ), and a field aperture that defines the shapes of the exposure fields PIa to PIe on the substrate 22 is provided at the intermediate image plane in the illumination optical systems ILa to ILe.

In the above embodiment, it is assumed that the projection optical systems 19a to 19e and the illumination optical systems ILa to ILe are fixed, and the substrate 22 is moved by the substrate stage 27. Alternatively, the following method may be used. In this configuration, the projection optical systems 19a to 19e and the illumination optical systems ILa to ILe are installed on the scanning stage, and the substrate 22 is scanned.

In addition, the mask 15 is not limited to a mask formed with a pattern on a glass substrate, and may also be a variable shaping mask including a digital multi-mirror device or a liquid crystal element.

According to the first embodiment and the modified example, the following effects can be obtained.

(1) The exposure device of the first embodiment or modification includes: projection optical systems 19a to 19e; illumination optical systems ILa to ILe, which supply illumination light to the projection optical systems 19a to 19e; and The scanning stage (substrate stage) 27 relatively scans the exposed substrate 22 and the projection optical systems 19a to 19e in the scanning direction, so that the scanning exposure field of view SIa to the projection optical system 19e formed by the projection optical system 19a to 19e is scanned. Exposure field of view SIe in non-scanning The exposed substrate 22 is exposed by overlapping a plurality of drawing directions, and the illumination optical systems ILa to ILe or the projection optical systems 19a to 19e have illumination changing members 10a to 10e. The components are set so that during exposure, compared with the cumulative exposure amount of the overlapping portions Oa to Od that are overlapped and exposed on the exposed substrate 22 , the components are exposed without overlapping on the exposed substrate 22 . The cumulative exposure amount of the non-overlapping portion Sa to Se becomes smaller.

According to the above configuration, the pattern is exposed and transferred using a non-additive photosensitive material in which the effective light exposure amount is reduced when the time is divided into a plurality of steps and the exposure is performed compared to the case where the time is continuously performed. In this case, it is also possible to prevent the line width or thickness of the transferred pattern between the overlapping portions Oa to Od and the non-overlapping portions Sa to Se where the respective scanning exposure fields SIa to SIe overlap. changes.

(2) The illumination optical systems ILa to ILe include optical integrators 11a to 11e, and the illuminance changing members 10a to 10e are light shielding members 10a to 10e provided at the following positions, that is: at The optical integrators 11a to 11e are located near the conjugate surface of the exposed substrate 22 and are separated from the conjugate surface by a predetermined distance in the direction of the optical axes IXa to IXe of the illumination optical systems ILa to ILe. , the predetermined distance is determined according to the width Wo of the overlapping portion Oa to the overlapping portion Od in the non-scanning direction, the lateral magnification of the conjugate plane and the exposed substrate 22, and the number of illumination light openings in the conjugate plane, and has The light-shielding member holding portion 9a to the light-shielding member holding portion 9e connect the light-shielding member 10a to the light-shielding member 10e to the illumination optical system ILa. The optical axes IXa to IXe of the illumination optical system ILe are substantially orthogonal to each other and the first direction optically corresponding to the scanning direction is movably maintained.

According to this structure, by moving the light shielding members 10a to 10e in the first direction, the cumulative exposure amount of the overlapping portions Oa to Od can be adjusted relative to the cumulative exposure amount of the non-overlapping portions Sa to Se. The ratio changes and decreases roughly continuously.

In the above, various embodiments and modifications have been described, but the present invention is not limited to the above. In addition, each of the embodiments and modifications may be applied individually or in combination. Other aspects that can be considered within the technical scope of the present invention are also included in the scope of the present invention.

The following disclosures of the basic priority application are incorporated herein by reference.

Japanese Patent Application No. 2019-002235 (filed on January 9, 2019).

9c: Light shielding member holding part

9c1: Slider

10c1, 10c2: light-shielding member

11c: compound eye lens

110: Lens unit

IPIc: area (area corresponding to exposure field of view)

IWs: Width (width) in the Y direction of the portion corresponding to the center area of the exposure field of view in the exposure field of view corresponding area

PX: The pitch (pitch) of the arrangement of the lens units in the X direction

W1, W2: Width (width) of the light shielding member in the Y direction

Claims (10)

An exposure device includes: a stage holding a substrate; a fly-eye lens including a first lens unit and a second lens unit, and is located at a position where an incident surface where illumination light is incident and the substrate form a conjugate surface; a first light shielding The second light-shielding portion is located on the incident surface side of the fly-eye lens and shields at least a part of the first lens unit; the second light-shielding portion is located on the incident surface side of the fly-eye lens and shields at least part of the first lens unit. A part of the second lens unit blocks light; the aperture is located at a position conjugate to the substrate in the optical path between the fly-eye lens and the substrate, and the illumination area of the substrate is set by the illumination light; and a control system to change the amount of light shielding of the first lens unit by the first light shielding part and the amount of light shielding of the second lens unit by the second light shielding part, so that the third light shielding part A light shielding part and the second light shielding part move in a predetermined direction. In the incident surface, the first lens unit and the second lens unit respectively include a first area and a second area, and the first area corresponds to In the aperture, the second area corresponds to an opening of the aperture, and in the optical axis direction of the fly-eye lens, an end of the first light shielding portion in the predetermined direction is in contact with the first lens. The first area of the unit overlaps but does not overlap with the second area, and an end of the second light-shielding portion in the prescribed direction overlaps with In a state where the second area of the second lens unit overlaps, the control system moves the first light shielding portion and the second light shielding portion in the predetermined direction. The exposure device according to claim 1, wherein the first light shielding part and the second light shielding part are disposed near the incident surface of the fly's eye lens, and the fly's eye lens includes a first lens block and a third lens block. Two lens blocks, the first lens block includes a plurality of the first unit lenses arranged along the first direction, and the second lens block includes a plurality of the first unit lenses arranged along the first direction. A second unit lens, and the first lens block and the second lens block are juxtaposed in a second direction crossing the first direction. With the first light shielding portion and the second light shielding portion part moves in the predetermined direction, in the direction of the optical axis, the number of the first lens units overlapping the first light shielding part and the number of the second lens units overlapping the second light shielding part The first light-shielding portion and the second light-shielding portion are respectively extended toward the predetermined direction by increasing the number of the light-shielding portions. The exposure device according to claim 2, which includes: a projection optical system including the aperture, and the stage moves the substrate along the scanning direction relative to the projection optical system in the following manner, and with the The non-scanning direction where the scanning direction intersects moves, that is, the overlapping portion extending along the scanning direction in the substrate is irradiated multiple times with the light passing through the projection optical system, the first light shielding portion and the third light shielding portion. Two light shielding parts are arranged in the direction of the optical axis A position separated from the incident surface by a predetermined distance, a width of the overlapping portion between the predetermined distance and the non-scanning direction, a lateral magnification of the incident surface and the substrate, and the width of the incident surface within the incident surface. The number of illumination light openings is determined accordingly. The exposure device according to claim 1, wherein the first light shielding part and the second light shielding part are disposed on the incident surface, or are conjugate to the incident surface closer to the light source side than the incident surface. The conjugate position of , or the position away from the conjugate position by a specified distance. The exposure device according to claim 4, wherein the control system independently moves the first light shielding portion and the second light shielding portion toward the prescribed direction. The exposure device according to claim 5, which includes: a projection optical system including the aperture, and the stage moves the substrate along the scanning direction relative to the projection optical system in the following manner, and with the Movement in the non-scanning direction where the scanning direction intersects, that is, irradiating the overlapping portion extending along the scanning direction in the substrate with light passing through the projection optical system multiple times, the first light shielding portion and the second The light shielding portion is provided at a position separated from the incident surface by a predetermined distance in the optical axis direction, and the predetermined distance is consistent with the width of the overlapping portion in the non-scanning direction and the lateral magnification of the incident surface and the substrate. , and the number of openings for illumination light in the incident surface is determined accordingly. The exposure device according to claim 6, wherein the fly-eye lens includes the A plurality of lens blocks of a plurality of lens units in the first direction are arranged in a second direction intersecting the optical axis direction and the first direction, and the light shielding member arranges at least one of the lens blocks in At least part of a portion of one or more lens units on one side in the first direction that is conjugated to a non-overlapping portion other than the overlapping portion is shielded from light. The exposure apparatus according to Claim 7, wherein m pieces of the light shielding member are arranged corresponding to each of m (m is a natural number greater than or equal to 2) lens blocks among the plurality of lens blocks. The exposure device according to claim 8, wherein the end of the other side opposite to the side of the first direction of the m light-shielding members is within the lens block. The arrangement period of the lens units in the first direction is P, and they are set at positions that differ only by P/m in the first direction. The exposure device according to any one of claims 6 to 9, which includes a plurality of the projection optical systems and an illumination optical system including the fly-eye lens in parallel, and a plurality of the projection optical systems and the illumination optical system including the fly-eye lens are exposed through one scanning exposure. The scanning exposure fields performed by the projection optical system overlap a plurality of fields in the non-scanning direction to expose the substrate.