JPH1187236A - Lighting optical device and exposure device having lighting optical device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a lighting optical device having the constitution, wherein the illuminance distribution of the surface to be illuminated is hard to receive the effects of the deformation and displacement of each structure, even when the light source and the main body of the device are supported with other structures. SOLUTION: A light source means 1 which is supported by a first structure B, a beam expander optical system 4 which is supported by the first structure B, and lighting optical system 7-10 which are supported by a second structure A, are provided. The lighting optical system has an incident surface, which is conjugate with the specified region of the body to be illuminated and has a specified magnitude, at the incident side of the second beam through the beam expander 4. The beam expander optical system 4 forms a beam, having a cross-sectional shape larger than the incident beam by just the specified amount as the second beam for allowing the fluctuations of the cross-sectional position of the second beam in the specified range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illumination optical apparatus and an exposure apparatus having the illumination optical apparatus, and more particularly to an exposure apparatus using an excimer laser light source and a method for manufacturing a semiconductor device using the exposure apparatus.

[0002]

2. Description of the Related Art Exposure apparatuses for manufacturing semiconductor elements, liquid crystal display elements, and the like are generally quite large apparatuses.
The floor space required for installation is large. In general, a mercury lamp or a laser light source is used as a light source in an illumination optical device of an exposure apparatus. It is. Therefore, especially in an exposure apparatus using an excimer laser light source, it is necessary to arrange the light source apparatus separately from the exposure apparatus body. Therefore, from the viewpoint of effective use of a clean room for a semiconductor manufacturing apparatus, an excimer laser light source having a large occupied area may be installed in a low-clean room below the clean room.

[0003]

In an illumination optical apparatus of an exposure apparatus, an optical integrator is used to uniformly illuminate a mask in a superimposed manner. This optical integrator must be efficiently illuminated with light from a light source. Must. However, as described above, when the excimer laser light source and the illumination optical device main body or the exposure device main body are installed on different floor slabs, the light beam illuminating the optical integrator is displaced due to deformation or displacement of the floor slab. . As a result, the uniformity of the illuminance distribution is deteriorated or the illuminance is reduced on the mask or the photosensitive substrate which is the surface to be illuminated.

The present invention has been made in view of the above-mentioned problem, and even if the light source and the apparatus main body are supported by different structures, the illuminance distribution on the surface to be illuminated will not be affected by the deformation or displacement of each structure. It is an object of the present invention to provide an illumination optical device having a configuration that is hardly affected by the influence, an exposure device having the illumination optical device, and a method for manufacturing a semiconductor device using the exposure device.

[0005]

According to the present invention, there is provided, in the present invention, a light source means supported by a first structure for supplying a first beam, and the first structure. A beam expander optical system for enlarging and shaping the first beam supplied from the light source means into a second beam having a predetermined cross-sectional shape, wherein the beam expander optical system is substantially supported by the first structure. An illumination optical system supported by the isolated second structure, and configured to illuminate a predetermined area of the illuminated object based on the second beam formed via the beam expander optical system; The illumination optical system has an incident surface having a predetermined size conjugate with the predetermined area of the object to be illuminated on an incident side of the second beam via the beam expander optical system, extract And a cross-sectional position of the second beam in a plane including the incident surface due to deformation and displacement of the first structure and the second structure within a predetermined range. Therefore, an illumination optical device is provided, wherein a beam having a cross-sectional shape larger by a predetermined amount than the incident surface is formed as the second beam.

According to a preferred aspect of the present invention, the illumination optical system includes: an optical integrator for forming a plurality of light source images based on the second beam via the beam expander optical system; A condenser optical system for condensing light from the plurality of light source images formed through an integrator to illuminate the illuminated object in a superimposed manner, wherein the incident surface is incident on the optical integrator. Plane.

According to another aspect of the present invention, there is provided the illumination optical device of the present invention as described above, and the illumination optical device illuminates a mask as the object to be illuminated, and is formed on the mask. An exposure apparatus for exposing a predetermined pattern onto a photosensitive substrate is provided. Further, there is provided a method of manufacturing a semiconductor device, comprising an exposure step of exposing a predetermined pattern formed on the mask onto the photosensitive substrate using the exposure apparatus of the present invention as described above. I do.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to a specific configuration of the present invention,
The illumination optical system collects light from the multiple light source images formed via the optical integrator and the optical integrator for forming multiple light source images based on the parallel beam passing through the beam expander optical system. And a condenser optical system for illuminating the object to be illuminated in a superimposed manner. The ideal parallel beam incident on the optical integrator along the optical axis is set to have a predetermined margin with respect to the incidence surface of the optical integrator.

Therefore, for example, the light source is tilted with respect to the optical axis due to deformation and displacement of the first and second structures, and as a result, the optical integrator is tilted with the parallel beam tilted with respect to the optical axis. Even if it is incident on the optical integrator, light may not enter some areas of the optical integrator incident surface unless the amount of displacement of the parallel beam in the plane including the optical integrator incident surface exceeds the set margin. Can be avoided. In other words, according to the present invention, the variation of the cross-sectional position of the parallel beam in a plane including the entrance surface of the optical integrator can be allowed within a predetermined range, so that the illuminance distribution on the surface to be illuminated can be changed or deformed. A configuration that is not easily affected by displacement can be realized. as a result,
With the exposure apparatus of the present invention, a uniform illuminance distribution can be obtained on the surface to be exposed, and stable and favorable exposure can be performed. Also, by using the exposure apparatus of the present invention,
A good semiconductor device can be manufactured.

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a diagram schematically illustrating a configuration of an exposure apparatus including an illumination optical device according to an embodiment of the present invention. In this embodiment, the present invention is applied to a step-and-repeat type exposure apparatus that sequentially transfers a mask pattern to each exposure region by sequentially repeating a process of collectively exposing a mask pattern to each exposure region (shot region) of a wafer. ing.

The exposure apparatus shown in FIG. 1 includes, as light source means, an excimer laser light source 1 for emitting light having a wavelength of, for example, 248 nm or 193 nm. The parallel beam supplied from the excimer laser light source 1 passes through a pair of deflection prisms 2 and a parallel plane plate 3 and then enters a beam expander optical system 4. Beam expander optical system 4
Is composed of a cylinder expander 4A composed of a pair of cylindrical lenses and an expander 4B composed of a pair of spherical lenses. In the beam expander optical system 4, the parallel beam is two-dimensionally expanded in a plane perpendicular to the reference optical axis AX (that is, the optical axis of the beam expander optical system) via the cylinder expander 4A and the expander 4B to a predetermined size. Shape into a cross-sectional shape.

In the exposure apparatus of the step-and-repeat system, since the entire shape of each exposure area is square,
The shape of the incident surface of the optical integrator 7 described later is also square. Therefore, in this embodiment, the cross-sectional shape of the parallel beam enlarged and shaped via the beam expander optical system 4 is a square. At least one of the pair of deflection prisms 2 is configured to be rotatable around the optical axis AX. Therefore, by rotating the pair of deflection prisms 2 around the optical axis AX relatively, the optical axis A
The angle of the parallel beam with respect to X can be adjusted.
That is, the pair of deflection prisms 2 constitute beam angle adjusting means for adjusting the angle of the parallel beam supplied from the excimer laser light source 1 with respect to the optical axis AX.

Further, the plane-parallel plate 3 is configured to be rotatable around two orthogonal axes in a plane perpendicular to the optical axis AX. Therefore, by rotating the parallel plane plate 3 around each axis and tilting it with respect to the optical axis AX, the parallel beam can be moved in parallel with respect to the optical axis AX.
That is, the plane-parallel plate 3 constitutes a beam translation means for translating the parallel beam supplied from the excimer laser light source 1 to the optical axis AX. In this way, the parallel beam from the excimer laser light source 1 via the pair of deflection prisms 2 and the parallel plane plate 3 is enlarged and shaped into a parallel beam having a predetermined cross-sectional shape via the beam expander optical system 4. The light enters the bending mirror M1.

The parallel beams deflected in the vertical direction by the bending mirror M1 are sequentially reflected by the bending mirrors M2 to M5, pass through the opening of the floor slab A on the upper floor, and enter the bending mirror M6. As shown in FIG. 1, the bending mirrors M2 to M5 are arranged such that the parallel beam deflected in the vertical direction by the bending mirror M1 and directed to the bending mirror M6 bypasses the pipe for supplying pure water and the pipe 12 for ventilation. Are located. The beam deflected in the horizontal direction by the bending mirror M6 enters the half mirror 5. The beam reflected by the half mirror 5 is guided to a displacement tilt detection system 6, and the beam transmitted through the half mirror 5 is guided to an optical integrator 7 such as a fly-eye lens.

FIG. 2 is a diagram schematically showing an internal configuration of the position shift inclination detection system of FIG. In FIG. 2, the parallel beam guided to the displacement tilt detection system 6 has a square cross-sectional shape as described above, and is incident on the half mirror 21. The light reflected by the half mirror 21 is
An image is formed on the four-divided sensor 23 via the second sensor 2. Thus, the quadrant sensor 23 can detect the inclination of the parallel beam incident on the optical integrator 7 with respect to the optical axis AX by taking the difference signal of the diagonal region among the four subregions. The output of the quadrant sensor 23 is supplied to the control system 24.

On the other hand, the light transmitted through the half mirror 21 is
Remaining in a parallel beam, it reaches another quadrant sensor 25. In this manner, the four-division sensor 25 can detect the displacement of the parallel beam incident on the optical integrator 7 with respect to the optical axis AX based on the signal of each divided region. The output of the quadrant sensor 25 is supplied to the control system 24. As described above, the half mirror 5, the half mirror 21, the condenser lens 22, and the four-divided sensor 2
Reference numeral 3 denotes an inclination detection system for detecting an inclination of the parallel beam incident on the optical integrator 7 with respect to the optical axis AX. Further, the half mirror 5 and the four-divided sensor 25 constitute a displacement detection system for detecting a displacement of the parallel beam incident on the optical integrator 7 with respect to the optical axis AX.

As described above, the control system 24 includes the optical axis AX of the parallel beam incident on the optical integrator 7.
The inclination information and the displacement information with respect to
And 25 respectively. Control system 24
Controls the drive of the pair of deflection prisms 2 and the plane-parallel plate 3 based on the supplied tilt information and positional deviation information as needed. The inclination of the parallel beam is corrected by adjusting the angle of the parallel beam incident on the optical integrator 7 with respect to the optical axis AX by the relative rotation of the pair of deflection prisms 2, and the optical integrator is driven by the rotation of the parallel plane plate 3. The parallel beam incident on 7 is moved in parallel with respect to the optical axis AX to correct the displacement of the parallel beam.

On the other hand, a light beam transmitted through the half mirror 5 and incident on the optical integrator 7 is two-dimensionally divided by a plurality of lens elements constituting the optical integrator 7, and the same number of lens elements as the number of lens elements at the rear focal position. Is formed. Light beams from a number of light source images formed via the optical integrator 7 enter the condenser lens 8. The luminous flux condensed by the condenser lens 8 is reflected by the bending mirror M
After being reflected by 7, the mask 8 on which a predetermined pattern is formed is illuminated in a superimposed manner. The luminous flux transmitted through the mask 9 forms a pattern image of the mask 9 on a wafer 11 serving as a photosensitive substrate via a projection optical system 10.

The mask 9 is mounted on a mask stage (not shown) in a plane perpendicular to the optical axis of the projection optical system 10. On the other hand, the wafer 11 is placed on a wafer stage (not shown) that can move two-dimensionally in a plane perpendicular to the optical axis of the projection optical system 10. In this way, the exposure is performed while moving the wafer stage and thus the wafer 11 with respect to the projection optical system 10, and thereby the wafer 1 is exposed by the step-and-repeat method.
The pattern of the mask 9 can be sequentially transferred to each of the exposure areas on 1.

In this embodiment, as shown in FIG.
The excimer laser light source 1, the pair of deflection prisms 2, the parallel plane plate 3, the beam expander optical system 4, and the bending mirror M1 are supported by a floor slab B on the lower floor as a first structure. The exposure apparatus main body including the bending mirror M6 and the optical integrator 7 is supported by an upper floor slab A which is a second structure substantially separated from the first structure. Further, the bending mirrors M2 to M5 are supported by a floor slab B on the lower floor or a floor slab A on the upper floor.

FIG. 3 is a developed optical path diagram from the excimer laser light source 1 to the optical integrator 7 in FIG. 1, and is a diagram for explaining the operation of the present invention. In FIG. 3, a pair of deflection prisms 2, a parallel plane plate 3, a folding mirror M
1 to M6 and the half mirror 5 are not shown. In the beam expander optical system 4 of FIG. 3, the expander 4B is omitted for simplification of description, and the parallel beam is expanded only in the plane of FIG. 3 via the cylinder expander 4A.

In FIG. 3, a parallel beam (shown by a solid line in FIG. 3) emitted from the excimer laser light source 1 along the optical axis AX has a positive refractive power on the paper of FIG. The light enters the first cylindrical lens 4a having no refracting power on a plane perpendicular to the paper surface. The beam once focused at a point on the optical axis AX via the first cylindrical lens 4a has a positive refractive power on the paper surface of FIG. 3 and has no refractive power on a surface passing through the optical axis AX and perpendicular to the paper surface. The beam becomes a parallel beam again via the second cylindrical lens 4b.
Thus, the parallel beam enlarged and shaped into a square cross section of a predetermined size via the beam expander optical system 4 enters the optical integrator 7.

As shown in FIG. 3, the incidence surface of the optical integrator 7 has a square cross section with a side length D. The parallel beam incident on the optical integrator 7 has a square cross section with one side being (D + 2W). That is, from the excimer laser light source 1 to the optical axis AX
In an ideal state in which a parallel beam is emitted along the optical integrator 7, the parallel beam incident on the optical integrator 7 along the optical axis AX has a margin W (margin width) on one side with respect to the incidence surface of the optical integrator 7. Is set.

On the other hand, for example, due to the deformation and displacement of the floor slab A on the upper floor and the floor slab B on the lower floor, the excimer laser light source 1
Is slightly inclined with respect to the optical axis AX, a parallel beam (indicated by a broken line in the figure) emitted from the excimer laser light source 1 at an angle of θ with respect to the optical axis AX becomes θ ′ with respect to the optical axis AX. The light reaches the incidence surface of the optical integrator 7 in a state of being tilted only. Here, the inclination θ ′ of the parallel beam incident on the optical integrator 7 with respect to the optical axis AX is obtained by calculating the inclination θ of the parallel beam emitted from the excimer laser light source 1 with respect to the optical axis AX by the angular magnification γ of the beam expander optical system 4. It is a value reduced only by

Then, as shown in FIG. 3, the parallel beam incident on the optical integrator 7 in a state of being inclined by θ ′ with respect to the optical axis AX is transmitted to the optical integrator 7 within a plane including the incident surface of the optical integrator 7. Is shifted from the ideal parallel beam incident along the optical axis AX by a distance Δ. At this time, the positional deviation amount Δ of the parallel beam is calculated from the surface C conjugate with the laser emission surface of the excimer laser light source 1 via the beam expander optical system 4.
Let d be the distance along the optical axis AX to the incident surface of. Δ = d · tanθ '(1)

If the amount of displacement Δ of the parallel beam is larger than the margin W of the parallel beam in an ideal state, a region where light does not enter some lens elements of the optical integrator 7 is generated. as a result,
The uniformity of the illuminance distribution is deteriorated on the mask 9 and the wafer 11 which are the illuminated surfaces, and an exposure error occurs particularly in a step-and-repeat type exposure apparatus. Therefore, in the present embodiment, the following conditional expression (2) needs to be satisfied between the displacement amount Δ and the margin W. Δ = d · tan θ ′ ≦ W (2)

In this embodiment, the cross-sectional shape of the parallel beam emitted from the excimer laser light source 1 is, for example, 17
mm × 4 mm, and the shape of the incident surface of the optical integrator 7 is, for example, 40 mm × 40 m
m square. In this case, the following conditional expression (3) is satisfied between the length D of one side of the incident surface of the optical integrator 7 and the margin W of the ideal parallel beam incident on the optical integrator 7 along the optical axis AX. Is preferably satisfied. 0.1 ≦ W / D ≦ 0.35 (3)

When the value exceeds the upper limit of conditional expression (3), the margin W of the ideal parallel beam incident on the optical integrator 7 becomes large, and the light quantity loss on the incidence surface of the optical integrator 7 becomes large. As a result, the illuminance on the wafer 11 decreases, and the throughput of the exposure apparatus decreases, which is not preferable. If the lower limit of conditional expression (3) is not reached, even if the excimer laser light source 1 is slightly inclined with respect to the optical axis AX, a region where light does not enter some lens elements of the optical integrator 7 is generated, A step-and-repeat type exposure apparatus is not preferable because an exposure error occurs.

As described above, in this embodiment, the ideal parallel beam incident on the optical integrator 7 is set to have a margin W with respect to the incidence surface of the optical integrator 7. Therefore, for example, the excimer laser light source 1 is tilted with respect to the optical axis AX due to deformation or displacement of the floor slab A on the upper floor and the floor slab B on the lower floor, and as a result, the parallel beam is tilted with respect to the optical axis AX. Even if the light enters the optical integrator 7 in this state,
As long as the positional deviation amount Δ of the parallel beam in the plane including the incident surface of the optical integrator 7 does not exceed the margin W, it is possible to avoid a situation where light does not enter a part of the incident surface of the optical integrator 7. it can. In other words, in the present embodiment, the variation of the cross-sectional position of the parallel beam in the plane including the entrance surface of the optical integrator 7 can be allowed within a predetermined range, and the illuminance distribution on the illuminated surface is higher than the floor of the upper floor. A configuration that is less susceptible to deformation and displacement of the plate A and the floor slab B on the lower floor can be realized. Therefore, in the exposure apparatus of this embodiment, a uniform illuminance distribution can be obtained on the surface to be exposed, and stable and good exposure can be performed.

Further, in the present embodiment, the inclination and the displacement of the parallel beam optical axis AX incident on the optical integrator 7 are detected by a displacement detection system and a displacement detection system, and based on the detected inclination information and displacement information,
By driving and controlling each of the pair of deflection prisms 2 and the parallel plane plate 3, the optical integrator 7 is controlled.
The tilt of the parallel beam incident on the optical integrator 7 is corrected by adjusting the angle of the parallel beam incident on the optical axis AX, and the parallel beam incident on the optical integrator 7 is moved in parallel with the optical axis AX to correct the displacement of the parallel beam. can do. Therefore, the excimer laser light source 1 is moved with respect to the optical axis AX by inelastic excessive deformation or displacement of the floor slab A on the upper floor and the floor slab B on the lower floor, or by the maintenance work of the excimer laser light source 1. Even in the case where the tilt and the position are constantly tilted, the constant tilt and the position shift can be appropriately corrected.

Further, in this embodiment, the folding mirror M
1 to M6 can be arranged in the parallel light beam path between the beam expander optical system 4 and the optical integrator 7. In other words, there is no need to dispose the bending mirrors M1 to M6 near the laser beam converging point, and therefore, there is no influence such as damage due to the converging point energy. As a result, the folding mirror can be freely arranged in the parallel light beam path when the apparatus is installed, and the piping for supplying pure water and the piping for ventilation at the site can be appropriately bypassed.

In this embodiment, as a beam angle adjusting means for adjusting the angle of the parallel beam supplied from the excimer laser light source 1 with respect to the optical axis AX, for example, the beam is orthogonal to the pair of deflection prisms 2 instead of the pair of deflection prisms 2. A vibrating mirror rotatable about two axes can be used.
In addition, in the positional deviation inclination detection system 6 of the present embodiment, a CCD camera or the like may be used instead of the four-divided sensors 23 and 25, and the detected image may be processed to obtain inclination information and positional deviation information.

FIG. 4 is a perspective view schematically showing a main part of a modification of the embodiment of FIG. In the modification of FIG. 4, the mask pattern is sequentially transferred to each exposure area of the wafer by repeating the process of scanning and exposing the mask pattern to each exposure area of the wafer while moving the mask and the wafer relative to the projection optical system. The present invention is applied to a step-and-scan type exposure apparatus. In FIG.
Although illustration of components from the excimer laser light source 1 to the half mirror 5 in FIG. 1 is omitted, the configuration from the excimer laser light source 1 to the half mirror 5 is the same as that of the embodiment of FIG.

In the modification shown in FIG. 4, the parallel beam emitted from the excimer laser light source 1 is enlarged and shaped into a predetermined cross-sectional shape via a beam expander optical system 4, and then the incident surface having a rectangular shape as a whole is formed. Incident on the first optical integrator 41 having the same. The light beam incident on the first optical integrator 41 is two-dimensionally divided by a plurality of lens elements constituting the first optical integrator 41, and forms the first optical integrator 41 at the rear focal position of the first optical integrator 41. The same number of light source images as the number of lens elements to be formed are formed.

Light beams from a plurality of light source images formed via the first optical integrator 41 are condensed by, for example, a condensing optical system 42 comprising a pair of lenses, and then have a square incident surface as a whole. The second optical integrator 43 is illuminated in a superimposed manner. The light beam incident on the second optical integrator 43 is two-dimensionally divided by a plurality of lens elements constituting the second optical integrator 43, and forms the first optical integrator 41 at the rear focal position of the second optical integrator 43. The number of light source images equal to the product of the number of lens elements to be formed and the number of lens elements constituting the second optical integrator 43 is formed.

The condensing optical system 42 makes the incident surface of the first optical integrator 41 and the incident surface of the second optical integrator 43 conjugate, and
The exit surface of the optical integrator 41 and the exit surface of the second optical integrator 43 are conjugate. Light beams from a number of light source images formed via the second optical integrator 43 are reflected by the bending mirror M8.
After being reflected in the vertical direction in the figure, the condenser lens 4
4 is incident. The light beam condensed by the condenser lens 44 illuminates the mask 45 on which a predetermined pattern is formed in a superimposed manner. The light beam transmitted through the mask 45 passes through the projection optical system 46 to the wafer 4 positioned on its image plane.
Reach seven. Thus, a pattern image of the mask 45 is formed on the wafer 47 which is a photosensitive substrate.

The wafer 47 is mounted on a wafer stage 48 which can move two-dimensionally in a plane perpendicular to the optical axis AX. On the other hand, the mask 45 is also mounted on a mask stage (not shown) that can move two-dimensionally in a plane perpendicular to the optical axis AX. In this manner, by performing scan exposure while relatively moving the mask 45 and the wafer 47 with respect to the projection optical system 46, the pattern formed in the pattern area of the mask 45 can be sequentially transferred to each exposure area on the wafer 47. it can.

In the step-and-scan type exposure apparatus, since the illumination area on the mask 45 is rectangular, the shape of the incident surface of the first optical integrator 41 is also rectangular. Therefore, in the modification, the cross-sectional shape of the parallel beam emitted from the excimer laser light source 1 is, for example, a rectangular cross section of 17 mm × 4 mm, and the shape of the incident surface of the first optical integrator 41 is, for example, a rectangular shape of 15 mm × 50 mm. in this case,
The following conditional expression (4) is satisfied between the length D1 of the long side of the incident surface of the first optical integrator 41 and the margin W1 in the long side direction of the ideal parallel beam incident on the first optical integrator 41. It is preferable to hold. Further, between the length D2 of the short side of the entrance surface of the first optical integrator 41 and the margin W2 in the short side direction of the ideal parallel beam incident on the first optical integrator 41, the following conditional expression (5) ) Is preferably satisfied. 0.05 ≦ W1 / D1 ≦ 0.35 (4) 0.2 ≦ W2 / D2 ≦ 0.4 (5)

If the upper limits of conditional expressions (4) and (5) are exceeded, the margin W of the ideal parallel beam incident on the first optical integrator 41 increases, and the margin W on the incident surface of the first optical integrator 41 is increased. Light amount loss increases. As a result, the illuminance on the wafer 47 decreases, and the throughput of the exposure apparatus decreases, which is not preferable. If the lower limits of conditional expressions (4) and (5) are not reached, even if the excimer laser light source 1 is slightly inclined with respect to the optical axis AX, light will be transmitted to some lens elements of the first optical integrator 41. This is not preferable because a non-incident region is generated, and an exposure amount unevenness occurs in a step-and-scan type exposure apparatus.

In the embodiment shown in FIG. 1, the parallel beam having a square cross section is reflected by the half mirror 5 and guided to the displacement tilt detection system 6. In the modification, the parallel beam having a rectangular cross section is used to detect the displacement tilt. Guided to the system. Therefore, in the modified example, it is necessary to interpose an expander between the half mirror 5 and the half mirror 21 of the displacement tilt detection system 6 and to shape the cross-sectional shape of the parallel beam guided to the displacement tilt detection system into a square. is there. Alternatively, an expander is interposed in the optical path between the half mirror 21 and the four-split sensor 23 and in the optical path between the half mirror 21 and the four-split sensor 25, and a cross section of the parallel beam guided to the displacement tilt detection system. The shape needs to be shaped into a square.

By the way, the wafer subjected to the exposure step (photolithography step) by the exposure apparatus of the present embodiment and the modified example is subjected to a developing step, an etching step for removing portions other than the developed resist, and a wafer after the etching step. The wafer process ends through a step of removing unnecessary resist and the like. When the wafer process is completed, in the actual assembling process, a dicing process in which the wafer is cut into chips for each printed circuit, a bonding process in which wiring and the like are provided to each chip, and a package in which each chip is packaged Finally, a semiconductor device such as an LSI is manufactured through a process such as a packaging process. In the present embodiment and the modified example, the example in which the semiconductor element is manufactured by the photolithography process using the exposure apparatus has been described. However, the liquid crystal display element, the thin film magnetic head, Other semiconductor devices such as (CCD elements, etc.) can be manufactured favorably.

In the above-described embodiments and modified examples, an example has been described in which an excimer laser that emits a parallel beam having a rectangular cross section is used as the light source means. For example, another light source that emits a parallel beam having a circular cross section is used. The present invention can be applied to the used exposure apparatus. In addition, in the above-described embodiments and modified examples, the present invention is applied to the step-and-repeat type exposure apparatus and the step-and-scan type exposure apparatus. However, the present invention can also be applied to a scan type exposure apparatus that collectively exposes a mask pattern to an entire exposure area of a wafer while moving the wafer and the mask relatively to the projection optical system. Further, in the above-described embodiments and modified examples, the example using the optical integrator including the fly-eye lens is described. However, for example, an internal reflection type rod-type optical integrator may be used instead of the fly-eye lens. .

[0043]

As described above, according to the present invention,
Since the variation of the cross-sectional position of the parallel beam within the plane including the entrance surface of the optical integrator can be tolerated within a predetermined range, the illuminance distribution on the illuminated surface even if the light source and the device main body are supported by different structures. Are not easily affected by deformation or displacement of each structure. As a result, in the exposure apparatus of the present invention, a uniform illuminance distribution can be obtained on the surface to be exposed, and stable and favorable exposure can be performed. Therefore, a good semiconductor device can be manufactured by using the exposure apparatus of the present invention.

[Brief description of the drawings]

FIG. 1 is a diagram schematically illustrating a configuration of an exposure apparatus including an illumination optical device according to an embodiment of the present invention.

FIG. 2 is a diagram schematically showing an internal configuration of a misalignment inclination detection system of FIG. 1;

FIG. 3 is a developed optical path diagram from the excimer laser light source 1 to the optical integrator 7 in FIG. 1, and is a diagram illustrating the operation of the present invention.

FIG. 4 is a perspective view schematically showing a configuration of a main part of a modification of the embodiment of FIG. 1;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 excimer laser light source 2 pair of deflection prisms 3 parallel plane plate 4 beam expander optical system 5, 21 half mirror 6 misalignment tilt detection system 7 optical integrator 8, 44 condenser lens 9, 45 mask 10, 46 projection optical system 11 , 47 Wafer 12 Piping 23, 25 Quadrant sensor 24 Control system 41 First optical integrator 42 Condensing optical system 43 Second optical integrator 48 Wafer stage AX Optical axis M1-M8 Folding mirror A Upper floor slab B Lower floor Floor slab

Claims (6)

[Claims] 1. A light source means supported by a first structure for supplying a first beam; and a first beam supported by the first structure and supplied from the light source means. A beam expander optical system for enlarging and shaping into a second beam having a predetermined cross-sectional shape; and a beam expander optical system supported by a second structure substantially isolated from the first structure. An illumination optical system for illuminating a predetermined area of the object to be illuminated based on the second beam formed through the system, wherein the illumination optical system is configured to transmit the second beam through the beam expander optical system. An incident surface having a predetermined size conjugate with the predetermined region of the object to be illuminated on the incident side of the second beam, wherein the beam expander optical system includes the first structure and the second structure. Structural In order to allow a variation of the cross-sectional position of the second beam in a plane including the incident surface due to a shape or displacement within a predetermined range, a cross-section larger than the incident surface by a predetermined amount as the second beam. An illumination optical device for forming a beam having a shape. 2. The illumination optical system is formed via an optical integrator for forming a large number of light source images based on the second beam via the beam expander optical system, and the optical integrator. A condenser optical system for condensing light from the plurality of light source images and illuminating the illuminated object in a superimposed manner, wherein the incident surface is an incident surface of the optical integrator. The illumination optical device according to claim 1. 3. The light source means has an excimer laser light source, and the beam expander optical system converts the first beam emitted from the excimer laser light source into a parallel beam after being once focused, The illumination optical device according to claim 1, wherein the light is emitted as the second beam. 4. A displacement detection system for detecting a displacement of the second beam with respect to an optical axis of the illumination optical system based on the second beam incident on the incident surface of the illumination optical system. Moving the first beam parallel to the optical axis of the beam expander optical system based on the output of the positional shift detection system to correct the positional shift of the second beam with respect to the optical axis. Beam translation means for causing the illumination optical system to emit light based on the second beam incident on the incident surface of the illumination optical system.
A tilt detection system for tilting the angle of the beam, and a beam expander for the first beam based on an output of the tilt detection system to correct the tilt of the second beam with respect to the optical axis. The illumination optical device according to claim 1, further comprising a beam angle adjustment unit configured to adjust an angle of the optical system with respect to an optical axis. 5. An illumination optical device according to claim 1, wherein the illumination optical device illuminates a mask as the object to be illuminated, and a predetermined pattern formed on the mask is provided. An exposure apparatus for exposing a photosensitive substrate. 6. A method for manufacturing a semiconductor device, comprising a step of exposing a predetermined pattern formed on the mask onto the photosensitive substrate using the exposure apparatus according to claim 5.