JP2001194803A - Device and method for illumination - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize illumination suitable for an exposure device by which a pattern is transferred without lowering a throughput even in the case of a large exposure area. SOLUTION: An illuminator combined with the exposure device to transfer the pattern on a first object to a second object and to illuminate the first object is provided with a light source to supply illuminating light, an illumination branching means to branch the illuminating light from the light source into plural illuminating light beams and a light-guiding means to respectively guide the plural illuminating light beams branched by the illumination branching means to plural illuminating areas on the first object.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an illumination device and method suitable for an exposure apparatus.

[0002]

2. Description of the Related Art In recent years, liquid crystal display panels have been frequently used as display elements for word processors, personal computers, televisions, and the like. A liquid crystal display panel is manufactured by patterning a transparent thin-film electrode on a glass substrate into a desired shape by a photolithography technique. As an apparatus for the lithography, a mirror projection type aligner that exposes an original pattern formed on a mask to a photoresist layer on a glass substrate via a projection optical system is used. As such an aligner, for example, FIG.
The one shown in (b) is known. FIG. 14A is a perspective view showing a configuration of a conventional aligner, and FIG.
It is a lens sectional view of the projection optical system of an aligner.

In FIG. 14A, a mask 71c is illuminated by an illumination optical system (not shown) in an arcuate illumination field 72a. As shown in FIG. 14B, the image 72b of the illumination field 72a has its optical path deflected by 90 ° at the reflection surface 73a of the trapezoidal mirror 73, and is reflected again by the concave mirror 74 via the concave mirror 74 and the convex mirror 75. You. The light from the concave mirror 74 has its optical path deflected by 90 ° on the reflection surface 73b of the trapezoidal mirror 73, and forms an image of the mask 71c on the plate 76. And
In this aligner, a plate 76 and a mask 71
The circuit pattern on the mask 71c was transferred onto the plate 76 by performing scanning exposure on the substrate 71c, that is, performing exposure while moving the substrate 71 along the X direction in the figure.

Recently, it has been desired to increase the size of a liquid crystal display panel. Along with that, even in the aligner as described above,
It is desired to enlarge the exposure area.

[0005]

In the projection exposure apparatus as described above, in order to enlarge the exposure area, the exposure area is divided and exposed. Specifically, as shown in FIG. 14A, the regions 76a, 76b, 76
c and 76d, the mask 71a and the region 7
6a is exposed by scanning to transfer the circuit pattern of the mask 71a onto the region 76a. Next, while replacing the mask 71a with the mask 71b, the plate 76 is moved stepwise in the XY plane in the figure so that the exposure area of the projection optical system and the area 76b overlap. Then, the mask 71b and the plate 76 are scanned and exposed, and the circuit pattern of the mask 71b is transferred onto the region 76b. Similarly, the circuit patterns of the masks 71c and 71d are respectively replaced with the regions 76c and
76d.

As described above, in the case of performing the exposure in a divided manner, the exposure (the amount of the substrate that can be exposed per unit time) is reduced because the exposure is performed many times.
Further, in order to collectively transfer a large exposure area, it is conceivable to increase the size of the projection optical system. However, in order to increase the size of the projection optical system, it is necessary to manufacture a large-sized optical element with extremely high precision, which causes a problem that the manufacturing cost increases and the size of the apparatus increases. Also, there is a problem that the aberration increases due to the enlargement of the projection optical system.

It is an object of the present invention to provide an illuminating apparatus and method suitable for an exposing apparatus capable of transferring a circuit pattern with good imaging performance without reducing throughput even when the exposure area is large. With the goal.

[0008]

In order to achieve the above object, an exposure apparatus according to the present invention has the following arrangement. The invention according to claim 1 is an illumination device that illuminates the first object in combination with an exposure device that transfers a pattern on a first object to a second object, and a light source that supplies illumination light;
Illumination branching means for branching illumination light from the light source into a plurality of illumination lights; and light guide means for guiding the plurality of illumination lights branched by the illumination branching means to a plurality of illumination areas on the first object, respectively. And;

According to a second aspect of the present invention, in the configuration of the first aspect, another light source different from the light source is further provided,
The illumination light from the another light source is guided to the illumination branching means. The invention according to claim 3 is based on claim 2
Wherein the illumination branching unit has a light guide for guiding light from a plurality of incident ends to a plurality of exit ends.

The invention according to claim 4 is the invention according to claim 1. The illumination branching means has a light guide for guiding light from an incident end to a plurality of exit ends. According to a fifth aspect of the present invention, in the configuration of the third or fourth aspect, the light guide includes an optical fiber bundled at random.

According to a sixth aspect of the present invention, in the configuration according to any one of the first to fifth aspects, the plurality of illumination areas on the first object have a trapezoidal shape. According to a seventh aspect of the present invention, in the configuration according to any one of the first to sixth aspects, an illumination field stop arranged conjugate with the first object is provided.

According to an eighth aspect of the present invention, in the configuration according to any one of the first to sixth aspects, the pattern on the first object is formed while moving the first object and the second object along the scanning direction. It is characterized in that it is combined with an exposure device for transferring to the second object. According to a ninth aspect of the present invention, in the configuration of the eighth aspect, the plurality of illumination regions include a first illumination region and a second illumination region different from the first illumination region,
The first and second illumination areas are formed at different positions in the scanning direction.

According to a tenth aspect of the present invention, in the configuration of the ninth aspect, the plurality of illumination areas include the first and second illumination areas.
And a third illumination area different from the second illumination area in the scanning direction.

According to an eleventh aspect of the present invention, in the configuration of the eighth aspect, the plurality of illumination regions include a first illumination region and a second illumination region different from the first illumination region.
The first and second illumination areas are formed at different positions in a non-scanning direction.

According to a twelfth aspect of the present invention, in the configuration of the eleventh aspect, the plurality of illumination areas include a third illumination area different from the first and second illumination areas, and
Is formed at a position different from the first and second illumination regions in the scanning direction.

The invention according to claim 13 is the invention according to claims 1 to 1.
3. The configuration according to claim 2, wherein the exposure apparatus is combined with an exposure apparatus including a plurality of projection optical systems for forming an image of the first object on a second object. According to a fourteenth aspect of the present invention, in the configuration of the thirteenth aspect, the plurality of projection optical systems have a plurality of viewing areas on the first object, and the plurality of illumination areas are similar to the plurality of viewing areas. There is a feature.

According to a fifteenth aspect of the present invention, in the configuration of the fourteenth aspect, the plurality of projection optical systems have no field stop. The invention according to claim 16 is an illumination method for illuminating a mask on which a predetermined pattern is formed, wherein illumination light is supplied from a light source, and the illumination light from the light source is split into a plurality of illumination lights. A plurality of branched illumination lights are respectively guided to a plurality of illumination regions on the mask.

According to a seventeenth aspect of the present invention, in the configuration of the sixteenth aspect, illumination light from another light source different from the light source is supplied, and the illumination light from the another light source is supplied to a plurality of illumination sources. It is characterized by branching into light. According to an eighteenth aspect of the present invention, in the configuration of the seventeenth aspect, when the illumination light is branched into the plurality of illumination lights, a light guide that guides light from a plurality of incident ends to a plurality of emission ends is used. Features.

According to a nineteenth aspect of the present invention, in the configuration of the sixteenth aspect, when the illumination light is split into the plurality of illumination lights, a light guide for guiding light from an incident end to a plurality of emission ends is used. It is characterized by. According to a twentieth aspect of the present invention, in the configuration of the eighteenth or nineteenth aspect, a randomly bundled optical fiber is used as the light guide.

The invention according to claim 21 is the invention according to claims 16 to
20. The configuration according to claim 20, wherein a plurality of trapezoidal illumination areas are formed on the first object.
The invention according to claim 22 is characterized in that, in the configuration according to any one of claims 16 to 21, a step of guiding light to an illumination field stop disposed conjugate with the first object is provided.

According to a twenty-third aspect of the present invention, in the configuration of the sixteenth aspect, the plurality of illumination areas have a first illumination having a side coinciding with an edge of an area on the first object on which the pattern is formed. It has a region. In the invention according to claim 24, in the configuration according to claim 23, the plurality of illumination regions are different from the first illumination region in a second illumination region.
Wherein the second illumination region has a trapezoidal shape or a hexagonal shape.

According to a twenty-fifth aspect of the present invention, in the exposure method for transferring a pattern on the first object to the second object, the first method uses the illumination method according to any one of the sixteenth to twenty-fourth aspects. A plurality of illumination areas on the object are illuminated. The invention according to claim 26 is an exposure method for transferring a pattern on the first object to the second object while moving the first object and the second object along a scanning direction. A plurality of illumination areas on the first object are illuminated using the illumination method according to any one of the preceding claims.

According to a twenty-seventh aspect of the present invention, in the constitution of the twenty-fifth or twenty-sixth aspect, an image of a pattern on the first object is formed on the second object. The invention according to claim 28 is characterized in that, in the constitution according to claim 25 or 26, an image of the pattern on the first object is formed in a plurality of regions on the second object.

According to a twenty-ninth aspect of the present invention, there is provided an illumination method for illuminating a mask on which a predetermined pattern is formed, wherein the illuminating device according to any one of the first to fifteenth aspects uses A plurality of illumination regions are formed. Here, in the present invention, an erect image refers to an image in which the horizontal magnification in the up, down, left, and right directions is positive.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of an exposure apparatus according to the present invention. In FIG. 1, the direction (scanning direction) in which the mask 8 on which a predetermined circuit pattern is provided and the plate 9 on which a resist is applied on a glass substrate is transported is indicated by X.
A coordinate system is used in which the axis and the direction orthogonal to the X axis in the plane of the mask 8 are the Y axis, and the normal direction of the mask 8 is the Z axis.

In FIG. 1, the exposure light from the illumination optical system 10 uniformly illuminates the mask 8 in the XY plane in the figure. The illumination optical system 10 preferably has, for example, a configuration as shown in FIG. FIG. 2 shows the illumination optical system 1 shown in FIG.
FIG. 3 is a diagram illustrating an example of a specific configuration of 0. In FIG. 2, a light source such as a mercury lamp that supplies g-line (435 nm) or i-line (365 nm) exposure light is provided inside the elliptical mirror 102. The light is condensed by the elliptical mirror 102 and forms a light source image at the incident end of the light guide 103. The light guide 103 forms a secondary light source surface having a uniform light intensity distribution at its emission ends 103a and 103b. Note that the light guide 103 is desirably composed of randomly bundled optical fibers.

The light beam emitted from the light guide 103 is
The light reaches the fly-eye lenses 105a and 105b via the relay lenses 104a and 104b, respectively. On the exit surface side of these fly-eye lenses 105a and 105b,
A plurality of secondary light sources are formed. Light from a plurality of secondary light sources passes through condenser lenses 106a and 106b provided such that a front focal point is located at a secondary light source forming position.
Field stop 1 having rectangular openings 107a and 107b
07 is illuminated uniformly. Exposure light passing through the field stop 107 has its optical path deflected by 90 ° by mirrors 109a and 109b via lenses 108a and 108b, respectively.
The lenses reach the lenses 110a and 110b. Here, lens 1
08a, 110a and lenses 108b, 110b are a relay optical system that conjugates the field stop 107 and the mask 8, and the exposure light passing through the lenses 110a, 110b transmits the image of the openings 107a, 107b of the field stop 107. Are formed as illumination regions 111a and 111b.

The apertures 107a, 1 of the field stop 107 are provided.
The shape of 07b is not limited to a rectangular shape. It is desirable that the shape of the illumination area be as similar as possible to the shape of the field of view of the projection optical system. Also, in FIG.
In order to simplify the description, the illumination areas 111c to 111g
Are shown only on the optical axis.
Although not shown in FIG. 2, the light guide 1
The exit end of 03 is provided corresponding to the number of illumination areas, and exposure light from the exit end of the light guide 103 (not shown) is supplied to these illumination areas 111c to 111g.

Further, as shown in FIG. 2, when the light quantity is insufficient with one light source, a configuration as shown in FIG. 3 may be applied. FIG. 3 is a diagram schematically illustrating a main part of a modification of the illumination optical system, and includes light sources 201 a to 201 such as mercury lamps.
The exposure light from c is converged by the elliptical mirrors 202a to 202c to form a light source image. The light guide 203 is provided such that the incident end is located at the light source image forming position, and the exposure light passing through the light guide 203 is distributed to the plurality of exit ends 203a to 203e with a uniform light intensity distribution.
The next light source surface is formed. It is desirable that the light guide 203 be configured by randomly bundling optical fibers similarly to the light guide 103 of FIG. Injection ends 203a-2
The optical path from 03e to the mask 8 is the same as the illumination optical system shown in FIG.

The plurality of illumination areas 111a as described above
Instead of a plurality of illumination optical systems forming ~ 111g, an illumination optical system which illuminates the mask 8 with one rectangular area extending in a direction (Y direction) orthogonal to the scanning direction (X direction) is applied. Is also good. As such an optical system, a system using a rod-shaped light source extending in the Y direction is conceivable. Now, below the mask 8, a plurality of projection optical systems 2a to 2g are arranged. Hereinafter, referring to FIG. 4, the projection optical systems 2a to 2g
Will be described. Since the projection optical systems 2a to 2g have the same configuration, only the projection optical system 2a will be described for the sake of simplicity.

FIG. 4 is a lens configuration diagram of the projection optical system 2a. The projection optical system 2a has a configuration in which two sets of Dyson optical systems are combined. 4, the projection optical system 2a includes first partial optical systems 21 to 24 and a field stop 25.
And second partial optical systems 26 to 29.
These first and second partial optical systems are respectively modifications of the Dyson optical system.

The first partial optical system is provided with 4
Right-angle prism 21 with reflecting surface arranged at an inclination of 5 °
And a plano-convex lens component 22 having an optical axis along the in-plane direction of the mask 8 and having a convex surface facing the opposite side of the right-angle prism 21
And a lens component 23 having a reflective surface with a meniscus shape as a whole and a concave surface facing the plano-convex lens component 22 side.
And a right-angle prism 24 having a reflection surface orthogonal to the reflection surface of the right-angle prism 21 and arranged at an angle of 45 ° with respect to the mask 8 surface.

The light from the illumination optical system through the mask 8 is deflected by 90 ° in the optical path by the right-angle prism 21, and the plano-convex lens component 22 joined to the right-angle prism 21
Incident on. A lens component 23 made of a glass material different from the plano-convex lens component 22 is joined to the lens component 22. Light from the right-angle prism 21 is refracted at a joining surface 22 a of the lens components 22 and 23. Reaches the reflection surface 23a on which the reflection film is deposited. The light reflected by the reflection surface 23a is refracted by the joint surface 22a and reaches the right-angle prism 24 joined to the lens component 22. The light from the lens component 22 is deflected by 90 ° in the optical path by the right-angle prism 24 to form a primary image of the mask 8 on the exit surface side of the right-angle prism 24. Here, the first partial optical systems 21 to 24
The primary image formed by the mask 8 is an equal-magnification image having a positive lateral magnification in the X direction (optical axis direction) and a negative lateral magnification in the Y direction.

The light from the primary image passes through the second partial optical system 26 to
Via 29, a secondary image of the mask 8 is formed on the plate 9. Note that the configuration of the second partial optical system is the same as that of the first partial optical system, and will not be described. Like the first partial optical system, the second partial optical systems 26 to 29 form the same magnification image having a lateral magnification in which the X direction is positive and the Y direction is negative. Therefore, the secondary image formed on the plate 9 is an erect image of the same magnification of the mask 8 (image having a positive horizontal magnification in the vertical and horizontal directions). Here, the projection optical system 2a (first and second partial optical systems) is a double-sided telecentric optical system.

The first and second partial optical systems described above include:
The reflecting surfaces 23a and 28a are configured to be in the same direction. This makes it possible to reduce the size of the entire projection optical system. The first and second partial optical systems according to the present embodiment include plano-convex lens components 22 and 27 and reflecting surfaces 23a and 23a.
8a is filled with a glass material in the optical path.
Thereby, the plano-convex lens components 22 and 27 and the reflecting surface 23
There is an advantage that eccentricity with the a and 28a does not occur.

As shown in FIG. 5, the first and second partial optical systems include plano-convex lens components 22, 27 and a reflecting surface 23.
The so-called Dyson-type optical system itself may be configured by using air between the a and 28a. For such a Dyson-type optical system, refer to JOSA vol. 49 (1959)
P713 to P716. In the present embodiment, the field stop 25 is arranged at the position of the primary image formed by the first partial optical system. The field stop 25 is, for example, as shown in FIG.
It has a trapezoidal opening as shown in FIG. The field stop 25 defines an exposure area on the plate 9 in a trapezoidal shape. Here, as shown by the broken line in FIG. 6B, in the Dyson optical system of the present embodiment, the lens component 22
Since the cross-sectional shape (YZ plane) of each of 23, 27, and 28 is circular, the region of the maximum possible visual field becomes substantially semicircular. At this time, the trapezoidal viewing region 8a defined by the field stop 25 preferably has a short side of the pair of parallel sides facing the arc side of a semicircular region (region of the largest field of view). Thereby, the width of the visual field region in the scanning direction (X direction) can be maximized with respect to the maximum visual field region that the Dyson optical system can take, and the scanning speed can be improved.

As shown in FIG. 6C, the field stop 25 may have a hexagonal opening. At this time, as shown in FIG. 6D, the size of the hexagonal opening is within the range of the maximum visual field area indicated by the broken line in the figure. 6 (b) and 6 (d), the maximum visual field area indicated by the broken line indicates that the outermost light beam among the off-axis light beams passing through the first and second partial optical systems without vignetting. This is an area surrounding a point passing on the mask 8.

Returning to FIG. 1, the arrangement of the projection optical systems 2a to 2g will be described. In FIG. 1, the projection optical system 2a
2g have field regions 8a to 8g defined by a field stop in the projection optical system. These viewing areas 8
The images a to 8g are formed as the same-size erect images on the exposure regions 9a to 9g on the plate 9. Here, the projection optical systems 2a to 2d are provided such that the field regions 8a to 8d are arranged along the Y direction in the drawing. Further, the projection optical systems 2e to 2g are provided at positions different from the viewing regions 8a to 8d in the X direction in the drawing so that the viewing regions 8e to 8g are arranged along the Y direction. At this time, the projection optical system 2
a to 2d and the projection optical systems 2e to 2g are provided such that their right-angle prisms are located extremely close to each other. Note that, in the X direction, the projection optical system 2 is configured to widen the interval between the visual field regions 8a to 8d and the visual field regions 8e to 8g.
Although a to 2 g may be arranged, at this time, the scanning amount (moving amount of the mask 8 and the plate 9) for performing the scanning exposure increases, which is not preferable because the throughput is reduced.

On the plate 9, projection optical systems 2a to 2d
The exposure regions 9a arranged along the Y direction in the drawing
9d are formed, and the projection optical systems 2e to 2g form exposure regions 9e to 9g arranged along the Y direction at positions different from the exposure regions 9a to 9d. These exposure areas 9a to 9g are erect images of the same size as the viewing areas 8a to 8d.

Here, the mask 8 is mounted on a mask stage (not shown), and the plate 9 is mounted on a plate stage 60. Here, the mask stage and the plate stage move synchronously in the X direction in the figure. As a result, the image of the mask 8 illuminated by the illumination optical system 10 is sequentially transferred onto the plate 9, and so-called scanning exposure is performed. The movement of the mask 8 causes the viewing area 8
When the scanning of the entire surface of the mask 8 by a to 8g is completed, the image of the mask 8 is transferred over the entire surface of the plate 9.

On the plate stage 60, a reflecting member 61 having a reflecting surface along the Y axis and a reflecting member 62 having a reflecting surface along the X axis are provided. On the side of the exposure apparatus main body, for example, He-Ne (633
nm), and a beam splitter 6 that divides the laser light from the laser light source 63 into laser light for X-direction measurement and laser light for Y-direction measurement.
4. The laser beam from the beam splitter 64 is reflected by the reflection member 6
A prism 65 for projecting the laser beam to the first member 1 and prisms 66 and 67 for projecting the laser beam from the beam splitter 64 to two points on the reflecting member 62 are provided. Thus, the position of the stage in the X direction, the position in the Y direction, and the rotation in the XY plane can be detected. In FIG. 1, a detection system for detecting the laser light reflected by the reflection members 61 and 62 and the reference laser light after making the laser light interfere with each other is not shown.

Next, the arrangement of the visual field regions according to the present embodiment will be described with reference to FIG. FIG. 7 shows a projection optical system 2a.
FIG. 9 is a diagram showing a planar positional relationship between the visual field regions 8a to 8g and the mask 8 by 2g. In FIG. 7, the mask 8
A circuit pattern PA is formed thereon, and a light-shielding portion LSA is provided so as to surround a region of the circuit pattern PA. The illumination optical system shown in FIG. 2 uniformly illuminates the illumination regions 111a to 111g surrounded by broken lines in the drawing. The visual field regions 8a to 8g described above are arranged in the illumination regions 111a to 111g. These field regions 8a to 8g have a substantially trapezoidal shape due to the field stop in the projection optical systems 2a to 2g. Here, the viewing area 8
The upper sides a to 8d (short sides of a pair of parallel sides) and the upper sides of the viewing areas 8e to 8g (short sides of a pair of parallel sides) are arranged to face each other. Here, the shapes of the viewing areas 8a and 8d along the light-shielding portion LSA are defined such that the oblique sides (the sides other than the pair of parallel sides) on the light-shielding portion LSA side coincide with the edges of the area of the circuit pattern PA. . Note that the shape may be such that the visual field regions 8a and 8d overlap the light shielding portion LSA of the mask 8.

In this embodiment, the projection optical systems 2a to 2a
Since g is a two-sided telecentric optical system, the area occupied by the projection optical systems 2a to 2g in the XY plane is larger than the area occupied by the visual field areas 8a to 8g, respectively. Therefore, the arrangement of the visual field regions 8a to 8d has to be configured so as to have an interval between the respective regions 8a to 8d. In this case, if scanning exposure is performed using only the visual field areas 8a to 8d, the area on the mask 8 between the visual field areas 8a to 8d cannot be projected and transferred onto the plate 9. Therefore, in the present embodiment, the visual field regions 8a to 8d
In order to perform the scanning exposure on the area between, the projection optical systems 2e to 2g are provided to provide the field areas 8e to 8g.

At this time, it is desirable that the sum of the widths of the visual field regions 8a to 8g (or the exposure regions 9a to 9g) along the scanning direction (X direction) is always constant at any position in the Y direction. Hereinafter, description will be made with reference to FIG. FIG.
(a) and (b) show the distribution of the exposure amount in the Y direction on the plate 9, in which the vertical axis shows the exposure amount E and the horizontal axis shows the position of the plate 9 in the Y direction. In FIG. 8A, on the plate 9, exposure dose distributions 90a to 90g corresponding to trapezoidal exposure regions 9a to 9g are obtained. Here, in the scanning exposure, since the sum of the widths of the exposure regions 9a to 9g in the X direction is defined to be constant, the same exposure amount is always obtained for the region where the exposure regions 9a to 9g overlap. For example, the exposure amount distribution 90a corresponding to the exposure region 9a and the exposure amount distribution 9 corresponding to the exposure region 9e
0e, the sum of the width of the exposure region 9a in the X direction and the width of the exposure region 9e in the X direction is constant. Therefore, the sum of the exposure amount of the overlapping region is the exposure amount of the non-overlapping region. Is the same exposure amount. Therefore, a uniform exposure distribution 91 is obtained on the entire surface of the plate 9. In the above description, the case where the exposure region has a trapezoidal shape is described. However, the combination of the exposure regions for obtaining a uniform exposure amount distribution is not limited to the trapezoidal shape.
For example, when a plurality of hexagonal exposure regions are formed by the field stop 25 as shown in FIG. 6C, each exposure region is defined such that the width of each exposure region in the scanning direction is always constant. Thereby, a uniform exposure amount distribution can be obtained over the entire surface of the plate 9.

Next, with reference to FIG. 9, a desirable arrangement relationship of the projection optical system in this embodiment will be described. FIG.
Is a plan view for explaining the arrangement of the projection optical system,
The projection optical systems D1, D2, and D3 are viewed from the mask 8 side (object side). 9, the projection optical system D1 comprises a plano-convex lens component L1 and a concave mirror M1, the projection optical system D2 comprises a plano-convex lens component L2 and a concave mirror M2, and the projection optical system D3 comprises a plano-convex lens component L3. And a concave mirror M3. Here, each projection optical system D1, D2,
The configuration of D3 is the same. In FIG. 9, for the sake of simplicity, the optical path of each of the projection optical systems D1, D2, and D3 is only the optical path from the object to the concave mirrors (reflecting mirrors) M1, M2, and M3. The right-angle prism that deflects the light to the right side is not shown.

Now, the maximum width of the visual field in the Y direction of the projection optical system D1 in the Y direction is φF1, the maximum width of the visual field in the Y direction of the projection optical system D2 is φF2, and the maximum width of the projection optical system D3 is φF2. The width of the largest viewing area in the Y direction is φF3. The widths φF1 to φF3 of these visual field areas in the Y direction correspond to the radial lengths of the maximum visual field areas indicated by broken lines in FIGS. 6B and 6D, respectively.

At this time, assuming that the distance between the optical axes of the projection optical systems D1, D3 arranged adjacently in the Y direction is K,

[0048]

It is desirable that the following formula is satisfied: φF1 / 2 + φF2 + φF3 / 2> K (1) Where φF1 = φF2 = φF3
Assuming that = φF (where φF is the maximum width of the field of view of each projection optical system in the Y direction), the above equation (1) can be rewritten as follows.

[0049]

2φF> K (2) That is, Y of the maximum field of view that each projection optical system can take
The width in the direction is preferably at least half the distance between the optical axes in the Y direction of each projection optical system. Here, it is not preferable that the arrangement of the projection optical systems deviates from the range of the above formula (1) or (2), since the respective viewing areas may not overlap in the Y direction.

The diameters (lengths in the Y direction) of the plano-convex lens components L1 to L3 are φL1 to φL3, and the diameters (lengths in the Y direction) of the concave mirrors M1 to M3 are φM1 to φM3. The larger diameter (ie, the projection optics D1, D2, D3)
Is the maximum value of the outer diameter of φD1 to φD3. Here, since the configuration of each projection optical system D1, D2, D3 is the same,

[0051]

## EQU3 ## The following holds: φL1 = φL2 = φL3, φM1 = φM2 = φM3, φD1 = φD2 = φD3 = φD. At this time, assuming that the maximum width of the field of view of each projection optical system in the Y direction is φF,

[0052]

It is desirable to satisfy the following expression: φF> φD / 2 (4) Here, each projection optical system D1
When D3 does not satisfy the above expression (4), that is, when the maximum width .phi.F in the Y direction of the maximum field of view that each projection optical system can take is not more than half of the maximum value .phi.D of the outer diameter of each projection optical system. ,
It is not preferable because the projection optical systems D1 and D3 arranged adjacent to each other in the Y direction may interfere with each other. When the maximum value of the outer diameter of the projection optical system is determined by the right-angle prism which deflects the optical path by 90 °, the maximum value φD of the outer diameter may be the length of the right-angle prism in the Y direction. Further, the relations of the above equations (1) to (4) are not limited to the Dyson-type optical system but can be applied to the Offner-type optical system.

In the above embodiment, two sets of optical systems are combined as the projection optical system.
The optical system shown in FIGS. 10 and 11 may be applied. FIG.
Numeral 0 indicates that a right-angle roof prism 34 having a roof surface is applied instead of the right-angle prism of the Dyson optical system. 10, a right-angle prism 31, a plano-convex lens component 32, and a lens component 33 having a reflection surface 33a are respectively a right-angle prism 21, a plano-convex lens component 22 shown in FIG.
Since it has the same function as the lens component 23, the description is omitted here. In a Dyson-type optical system having two sets of right-angle prisms, the lateral magnification in the direction along the optical axis is positive and the direction orthogonal to the optical axis (the direction along the object plane and the image plane).
An image having a negative lateral magnification is formed. In the Dyson optical system having the right-angle roof prism 34 as shown in FIG. 10, the image direction in the direction perpendicular to the optical axis (perpendicular to the paper plane) in the object plane and the image plane is reversed by the roof plane. (X direction) and a direction orthogonal to the optical axis in the object plane and the image plane (Y
Direction), an erect image in which both lateral magnifications are positive can be formed.

FIG. 11 is a lens configuration diagram of an example of a Dyson-type optical system provided with a reflecting surface for turning an optical path.
In FIG. 11, the light from the mask 8 is applied to a semi-reflective surface 41 inclined at 45 ° to the light incident direction (Z-axis direction).
By a, the optical path is deflected by 90 ° and enters the plano-convex lens component. The plano-convex lens component 4 shown in FIG.
2 and a lens component 43 joined to the plano-convex lens component 42
Have the same functions as the plano-convex lens component 22 and the lens component 23 of FIG. 4, respectively.

Then, the light incident on the plano-convex lens component 42 is reflected by the reflection surface 43a, and is again reflected by the plano-convex lens component 4.
2, a primary image of the mask 8 is formed on the exit side of the plano-convex lens component 42. The reflection surface 4 is located at the primary image forming position.
1b is provided. Here, the semi-reflective surface 41a and the reflective surface 41b are provided on the reflective member 41. The light from the primary image on the reflection surface 41b travels in the original optical path backward, passes through the plano-convex lens component 42 and the lens component 43, and then passes through the semi-reflection surface 41a. The transmission direction of the semi-reflective surface 41a is 1
The reflecting surface 44a inclined at 12.5 ° and the reflecting surface 4
A reflection member 44 having a reflection surface 44b inclined at 45 ° to 4a is provided. Here, the reflection surface 44
Since the light beams a and 44b have the function of a pentaprism, the light incident on the reflection member 44 is deflected by 90 ° in the optical path by the reflection on the reflection surfaces 44a and 44b.

The light reflected by the reflecting surfaces 44a and 44b is
A secondary image of the mask 8 is formed on the exit side of the reflection member 44.
Here, this secondary image is an erect image of the same magnification. In FIG. 11, the optical path length from the mask 8 to the reflecting surface 41b is equal to the optical path length from the reflecting surface 41b to the plate 9. Here, in the projection optical system shown in FIG. 11, the shape of the reflecting surface 41b becomes the shape of the field stop. For example, when the trapezoidal reflection surface 41b whose short side is on the upper side of the paper surface in the YZ plane, the viewing region and the exposure region are trapezoidal regions in which the short side is located on the right side of the paper surface on the XY plane. In the projection optical system of FIG.
The light flux passing near the optical axis of the plano-convex lens component 42 and the lens component 43 does not reach the reflecting surface 41b and does not contribute to image formation. However, from the semi-reflective surface 41a to the reflective surface 43
In order to avoid mixing of the optical path going to the reflecting surface 41b and the optical path going from the reflecting surface 41b to the reflecting surface 43a, the plano-convex lens component 4
It is rare to use a light beam passing on and near the optical axis of the lens component 2 and the lens component 43. Therefore, as shown in FIG.
Even if the light beam passing near the optical axis of the plano-convex lens component 42 and the lens component 43 is shielded, there is no problem in practice.

It is needless to say that the projection optical system shown in FIGS. 10 and 11 may have a configuration in which the object side and the image side are reversed. In the projection optical system shown in FIG. 11 as described above, two reflecting surfaces 44a and 44b having the same function as the pentaprism are applied. Instead, as shown in FIG. 12, a reflecting surface for turning back the optical path is used. May be composed of two reflecting surfaces. In FIG. 12, a different point from the projection optical system of FIG. 11 is that two reflection surfaces 51 forming a roof surface having a ridge line along the Y direction (perpendicular to the paper surface) are provided.
b and 51c are provided instead of the reflecting surface 41b for turning back the optical path, and a reflecting surface 54a inclined at 45 with respect to the surface of the plate 9 is provided instead of the two reflecting surfaces 44a and 44b. In FIG. 12, the plano-convex lens component 52
The lens component 53 having the reflection surface 53a has the same function as the plano-convex lens component 42 and the lens component 43 of FIG. 11, respectively.

In FIG. 12, the light path from the mask 8 is deflected by 90 ° at the semi-reflective surface 51a, and the light is reflected by the reflective surfaces 51b and 51 via the plano-convex lens component 52 and the lens component 53.
c and a primary image of the mask 8 is formed. This primary image is turned upside down by the reflecting surfaces 51b and 51c,
Again through the plano-convex lens component 52 and the lens component 53,
The light passes through the semi-reflective surface 51a. The light transmitted through the semi-reflective surface 51a is deflected by 90 ° in the optical path at the reflective surface 54a, exits from the reflective member 54, and forms a secondary image of the mask 8. Here, this secondary image is an erect image of the same magnification.

In the above embodiment, a Dyson-type optical system having a plano-convex lens component and a concave mirror is applied as a projection optical system for obtaining an erect image at the same magnification. It is not limited to. For example, as shown in FIG. 13, an Offner-type optical system in which a concave mirror, a convex mirror, and a concave mirror are sequentially arranged can be applied. FIG. 13 shows an application of the Offner type optical system shown in FIG. 14 (b) as the first and second partial optical systems. For simplicity, the same members as those shown in FIG. 14 (b) are used. Members having functions are given the same reference numerals. In FIG. 13, a field stop 25 having an arc-shaped opening is provided at a primary image forming position of the mask 8 formed by the first partial optical system. Even with such two sets of Offner-type optical systems, it is possible to obtain a projection optical system that is telecentric on both sides (object side and image side) and forms an erect image of the same size as an object.

From the above, it can be seen that the projection optical system for obtaining an erect image of the same magnification can have various configurations. In addition,
In a projection optical system that does not form an intermediate image (primary image) as shown in FIG. 10 or an optical system in which a field stop cannot be arranged at an intermediate image forming position as shown in FIG. 12, the shape of the illumination area by the illumination optical system is desired. May be made similar to the shape of the visual field region. For example, the field stop 10 of the illumination optical system shown in FIG.
If the shapes of the openings 107a and 107b are trapezoidal, a trapezoidal illumination area can be obtained.

As described above, according to the exposure apparatus of this embodiment, since a plurality of projection optical systems form an exposure area having a wide width orthogonal to the scanning direction, each projection optical system is enlarged. This makes it possible to cope with an increase in the screen size of the exposure area without any problem. Here, in the present embodiment, since the projection optical system does not increase in size, there is an advantage that an increase in aberration due to proportional enlargement can be prevented.

Further, in the present embodiment, since exposure of a large screen can be performed by one exposure without repeating the screen, there is an advantage that the throughput can be improved and that there is no seam of the screen.

[0063]

As described above, according to the present invention, it is possible to provide an illumination apparatus and method suitable for an exposure apparatus capable of transferring a circuit pattern without reducing throughput even when the exposure area is large.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of the present invention.

FIG. 2 is a perspective view showing an example of an illumination optical system applied to the exposure apparatus according to the present invention.

FIG. 3 is a diagram schematically showing a modification of the illumination optical system.

FIG. 4 is a lens configuration diagram of a projection optical system applied to the exposure apparatus according to the present invention.

FIG. 5 is a lens configuration diagram showing a modification of the projection optical system.

FIG. 6 is a plan view for explaining the shape of a field stop.

FIG. 7 is a diagram illustrating a planar positional relationship between a field of view and a mask by a projection optical system.

FIG. 8 is a diagram showing an exposure amount distribution on a plate.

FIG. 9 is a plan view for explaining an arrangement relationship of a plurality of projection optical systems.

FIG. 10 is a lens configuration diagram showing a modification of the projection optical system.

FIG. 11 is a lens configuration diagram showing a modification of the projection optical system.

FIG. 12 is a lens configuration diagram showing a modification of the projection optical system.

FIG. 13 is a lens configuration diagram when an Offner-type optical system is applied as a projection optical system.

FIG. 14 is a perspective view showing an example of a conventional exposure apparatus.

[Explanation of symbols]

 2a to 2g: projection optical system, 8: mask, 9: plate, 10: illumination optical system,

Claims (29)

[Claims] An illumination device for illuminating the first object in combination with an exposure device for transferring a pattern on a first object to a second object; and a light source for supplying illumination light; and an illumination light from the light source. And a light guiding unit that guides the plurality of illumination lights branched by the illumination branching means to a plurality of illumination regions on the first object, respectively. Lighting device characterized by the following. 2. The illumination device according to claim 1, further comprising another light source different from the light source, wherein illumination light from the another light source is guided to the illumination branching unit. 3. The illumination device according to claim 2, wherein the illumination branching unit has a light guide that guides light from a plurality of incident ends to a plurality of exit ends. 4. The illumination device according to claim 1, wherein the illumination branching unit has a light guide for guiding light from an incident end to a plurality of exit ends. 5. The lighting device according to claim 3, wherein the light guide has an optical fiber bundled at random. 6. The lighting device according to claim 1, wherein the plurality of illumination areas on the first object have a trapezoidal shape. 7. The illumination device according to claim 1, further comprising an illumination field stop disposed conjugate with the first object. 8. An exposure apparatus for transferring a pattern on the first object to the second object while moving the first object and the second object along a scanning direction. The lighting device according to any one of claims 7 to 7. 9. The plurality of illumination areas include a first illumination area and a second illumination area different from the first illumination area, wherein the first and second illumination areas are arranged in the scanning direction. The lighting device according to claim 8, wherein the lighting device is formed at different positions. 10. The plurality of illumination areas include a third illumination area different from the first and second illumination areas, wherein the third illumination area is different from the second illumination area in the scanning direction. 10. The lighting device according to claim 9, wherein the light sources are formed at different positions. 11. The plurality of illumination areas include a first illumination area and a second illumination area different from the first illumination area, wherein the first and second illumination areas are in a non-scanning direction. The lighting device according to claim 8, wherein the lighting device is formed at different positions. 12. The plurality of illumination areas include a third illumination area different from the first and second illumination areas, wherein the third illumination area has the first and second illumination areas in the scanning direction. The lighting device according to claim 11, wherein the lighting device is formed at a position different from a lighting area. 13. The illumination device according to claim 1, wherein the illumination device is combined with an exposure device including a plurality of projection optical systems that form an image of the first object on a second object. . 14. The plurality of projection optical systems have a plurality of viewing areas on the first object, and the plurality of illumination areas are similar to the plurality of viewing areas. Lighting equipment. 15. The illumination device according to claim 14, wherein the plurality of projection optical systems have no field stop. 16. An illumination method for illuminating a mask on which a predetermined pattern is formed, comprising: supplying illumination light from a light source; branching the illumination light from the light source into a plurality of illumination lights; An illumination method, wherein the illumination light is guided to a plurality of illumination areas on the mask. 17. The lighting device according to claim 16, wherein illumination light from another light source different from the light source is supplied, and the illumination light from the light source and the another light source is split into a plurality of illumination lights. Lighting method. 18. The illumination method according to claim 17, wherein when the illumination light is split into the plurality of illumination lights, a light guide for guiding light from a plurality of incident ends to a plurality of emission ends is used. . 19. The illumination method according to claim 16, wherein when the illumination light is split into the plurality of illumination lights, a light guide for guiding light from an incident end to a plurality of emission ends is used. 20. The illumination method according to claim 18, wherein a randomly bundled optical fiber is used as the light guide. 21. The illumination method according to claim 16, wherein a plurality of trapezoidal illumination areas are formed on the first object. 22. The illumination method according to claim 16, further comprising a step of guiding light to an illumination field stop arranged conjugate with the first object. 23. The method according to claim 16, wherein the plurality of illumination areas have a first illumination area having a side coinciding with an edge of an area on the first object on which the pattern is formed. Lighting method. 24. The light source device according to claim 24, wherein the plurality of illumination areas have a second illumination area different from the first illumination area, and the second illumination area has a trapezoidal shape or a hexagonal shape. 24. The lighting method according to claim 23. 25. The method according to claim 25, wherein the pattern on the first object is the second object.
25. An exposure method for transferring to an object, wherein the illumination method according to claim 16 is used to illuminate a plurality of illumination regions on the first object. 26. A pattern on the first object is moved by the second object while moving the first object and the second object along the scanning direction.
25. An exposure method for transferring to an object, wherein the illumination method according to claim 16 is used to illuminate a plurality of illumination regions on the first object. 27. The exposure method according to claim 25, wherein an image of a pattern on the first object is formed on the second object. 28. An image of a pattern on the first object is formed on a second object.
27. The exposure method according to claim 25, wherein the exposure method is formed in a plurality of regions on the object. 29. An illumination method for illuminating a mask on which a predetermined pattern has been formed, wherein the plurality of illumination regions are formed on the mask using the illumination device according to claim 1. A lighting method characterized by the above-mentioned.