JP2000150371A - Aligner and manufacture of semiconductor element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly efficiently and uniformly irradiate a surface to be irradiated with light by using zonal luminous flux transforming means which transform exposing light into zonal luminous fluxes and making the outside diameters of the zonal luminous fluxes from the transforming means variable. SOLUTION: A first prism member 20 has a concave conical refracting surface on the entrance side and a convex conical refracting surface on the exit side and can be exchanged with a second prism member 21 by means of a first exchanging means 10. The second prism member 21 has a recessed conical refracting surface on the entrance side and a convex refracting surface on the exit side and the refracting surfaces are formed so that the axial thickness (the distance between apexes) of the member 21 may become smaller than that of the first member 20. The zonal parallel luminous flux transformed by means of the first member 20 has the same zonal width as the zonal parallel luminous flux transformed by means of the second member 21 has, but the outside diameter of the former is larger than that of the latter.

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 for uniformly illuminating a surface to be irradiated, and more particularly to an illumination optical apparatus suitable for an exposure apparatus for manufacturing semiconductors.

[0002]

2. Description of the Related Art Conventionally, the manufacture of semiconductor devices such as LSIs and VLSIs has been performed by a projection exposure apparatus that reduces and projects a circuit pattern formed on a reticle onto a wafer via a projection lens. However, there is a strong desire to transfer a finer pattern onto a wafer, and great efforts have been made to meet this demand. For example, efforts have been made to improve the resolving power of the projection lens due to the shortening of the wavelength of the exposure light and the increase in the numerical aperture (hereinafter, referred to as NA) of the projection lens.
Projection lenses that exceed the standard are realized.

In addition, efforts are being made to improve the resolution and depth of focus of the projection lens by optimizing the illumination conditions based on the minimum line width of the pattern to be exposed. For example, in Japanese Patent Application Laid-Open No. 59-155843, an appropriate balance between the resolution and the contrast of a predetermined pattern is obtained by optimizing the ratio of the NA of the illumination optical system to the NA of the projection lens, that is, the σ value. What has been proposed.

In recent years, a fly-eye lens provided in an illumination optical system for exposure has been developed.
Attempts have been made to further improve the resolving power and depth of focus of the projection lens by changing the shape of the secondary light source, for example, proposed in Japanese Patent Application Laid-Open No. 61-91622. According to this publication, the central portion of the fly-eye lens forming the secondary light source on the emission side is shielded from light by an aperture, and an eccentric light source is formed. Significant improvements have been made.

[0005]

Generally, in this type of illumination optical apparatus for exposure, when a fine pattern is transferred onto a wafer, a mask (or reticle) as an irradiated surface is used to improve throughput. Requires uniform illumination under a higher illuminance. However, JP-A-61-9
In the lighting device proposed in Japanese Patent No. 1622, a ring-shaped 2
In order to obtain the next light source, a stop for shielding the central portion on the emission side of the fly-eye lens is arranged. For this reason, the total amount of irradiation light decreases, and the illuminance on a mask (hereinafter, referred to as a reticle) as a surface to be irradiated is significantly reduced.

As a result, there has been a problem that the exposure time is prolonged and a decrease in throughput is unavoidable. The present invention overcomes the above-mentioned problems and provides a high-performance illumination optical device capable of uniformly illuminating a surface to be illuminated with high illumination efficiency by forming an annular secondary light source without any light shielding. It is intended to be.

[0007]

In order to achieve the above object, the present invention provides a light source means 1 for supplying a substantially parallel light beam and a plurality of parallel light beams from a light source means 2 as shown in FIG. Optical integrator 3 for forming a secondary light source, and the optical integrator 3
A condenser lens 4 for condensing light beams from a plurality of secondary light sources formed by the light source and illuminating the irradiated surface R in a superimposed manner.
And an optical path between the optical integrator 3 and the optical integrator 3. An annular light beam converting means 2 for converting a substantially parallel light beam into an annular light beam is provided, and the annular light beam converting means 2 has an optical member having a conical refracting surface. It was made.

Based on the above basic configuration, the optical member has first and second refraction members (20, 21) having conical refraction surfaces, and the first and second refraction members (2, 21) have a conical refraction surface.
0, 21) is preferably provided so as to be insertable into the parallel optical path. Thereby, the ratio of the inner diameter to the outer diameter of the annular parallel light beam can be changed under high illumination efficiency.

As shown in FIG. 2, the annular luminous flux converting means 2 includes first and second refraction members (22, 2) having at least one surface having a convex conical refraction surface or a concave conical refraction surface.
3) the first and second refraction members (22, 23)
May be provided such that a relative interval is variably provided, and by changing the interval, the orbicular luminous flux diameter is variable. Thus, the ratio of the inner diameter to the outer diameter of the annular parallel light beam can be continuously changed under high illumination efficiency.

Further, as shown in FIG. 3, an afocal variable power optical system 30 may be provided between the annular light beam converting means 2 and the optical integrator 3. By changing the magnification of the afocal variable power optical system, the outer diameter of the orbicular luminous flux can be continuously changed.

[0011]

With the apparatus of the present invention, the parallel light flux from the light source is not blocked at all by the refraction of the annular light flux conversion means (a convex conical refraction surface or a concave conical refraction surface).
The light can be converted into an annular light beam, and as a result, an annular integrator can be formed by the optical integrator. Therefore, since the reticle as the surface to be irradiated can be uniformly illuminated under high illuminance, the throughput does not decrease.

Further, the annular light beam converting means has a plurality of members having a convex conical refracting surface or a concave conical refracting surface, and the plurality of members are replaceable or the interval between the plurality of members is reduced. By being variably provided, the ratio of the inner diameter to the outer diameter of the orbicular parallel light beam, that is, the so-called orbicular zone ratio, can be changed under high illumination efficiency. Therefore, since a secondary light source having an arbitrary ring zone ratio can be formed, a pattern on the reticle R can be transferred onto a wafer with an optimum line width and an optimum depth of focus.

Further, if an afocal variable power optical system is provided in the illumination optical system, the diameter (outside diameter) of the annular parallel light flux is maintained while the ring ratio is kept constant by the variable power of the afocal variable power optical system. ) Can be changed. Therefore, the annular ratio can be changed by the annular luminous flux converting means, and the annular parallel light can be changed by the afocal variable power optical system without changing the annular ratio. Diameter) can be controlled independently.

[0014]

1 shows a configuration according to a first embodiment of the present invention. In FIG. 1, (A) shows a first annular luminous flux conversion state, and (B) shows a second annular luminous flux. The conversion state is shown. Hereinafter, the first embodiment will be described in detail with reference to FIG. As shown in FIG. 1A, a substantially parallel light beam is supplied from the light source unit 1. The light source unit 1 has a mercury arc lamp, an elliptical mirror, and a collimator lens, and light from the mercury arc lamp (for example, light such as g-line (436 nm) and i-line (365 nm)).
Is condensed by an elliptical mirror and then converted into a parallel light beam by a collimator lens. In addition, the light source unit 1 includes a KrF
And a beam expander for shaping the beam diameter, and supplying a collimated light beam from the excimer laser light source via the beam expander.

The substantially parallel light beam supplied from the light source unit 1 is:
As shown by oblique lines, the light passes through the first prism member 20 and is converted into an annular parallel light beam. The first prism member 20 has a concave conical refracting surface on the incident side and a convex conical refracting surface on the exit side, and as shown in FIG. It is provided so as to be replaceable with the member 21. The second prism member 21 has a concave conical refracting surface on the incident side and a convex conical refracting surface on the exit side, and has a smaller axial thickness (distance between vertices) than the first prism member 20. It is configured as follows.

The annular parallel light flux of FIG. 1A converted by the first prism member 20 is compared with the annular parallel light flux of FIG. 1B converted by the first prism member 20. Although the width of the band is constant, the outer diameter of the annular parallel light beam is largely converted. For this reason, each prism member (2
Assuming that the inner and outer diameters of the annular parallel light beam formed by (0, 21) are r ₁ and r ₂ , respectively, the annular parallel light beam converted by the first prism member 20 shown in FIG. The ring ratio (r ₁ / r) is larger than the ring-shaped parallel light flux converted by the second prism member 21 shown in FIG.
r ₂ ) becomes smaller. Therefore, each prism member (20,
It can be seen that the ring zone ratio can be made variable by inserting 21) into the optical path. In the present embodiment, the first prism member 20 and the second prism member 21 constitute the orbicular luminous flux conversion unit 2.

Returning to FIG. 1A, the light beam converted into an orbicular parallel light beam having a predetermined orbicular ratio by the first prism member 20 is formed into an orbicular shape by a fly-eye lens 3 as an optical integrator. A plurality of secondary light sources are formed. The fly-eye lens 3 is constituted by an aggregate of a plurality of rod-shaped lens elements. A secondary light source image is formed, where a substantially annular surface light source is formed. Therefore, the diameter of the parallel luminous flux incident on the fly-eye lens 3 and the ring ratio change by replacing the prism members (20, 21), so that the size and the ring ratio of the secondary light source image in the ring shape are reduced. Be variable.

At a position on the exit side of the fly-eye lens 3 where the annular secondary light source image is formed, there is provided aperture stop means 4 for accurately defining an annular parallel light beam.
The aperture stop means 4 has aperture stops 41 and 42 having a predetermined ring-shaped aperture.
In conjunction with insertion into the prism member 21, the second exchange means 11 is provided so as to be exchangeable with an aperture stop 42 having another annular aperture and annular ratio by the second exchange means 11.

The luminous flux from the secondary light source in the form of an annular zone via the aperture stop 41 is condensed by the condenser lens 5 as shown by oblique lines, and overlaps the pattern area on the reticle R from an oblique direction. Illuminate uniformly. Then, a circuit pattern image on the reticle R is formed on the wafer W by the projection lens 6 (projection optical system). Accordingly, the resist applied on the wafer W is exposed, and the circuit pattern image of the reticle R is transferred here. An aperture stop 6a having a variable aperture is provided at a pupil (entrance pupil) position of the projection optical system 6, and the aperture stop 6a is set to a predetermined aperture by the aperture variable means 12. The aperture stop 6a is provided conjugate with the aperture stop 6 provided on the exit side of the fly-eye lens 3, as shown by the dotted line in FIG.

Next, the operation according to the present embodiment will be described. First, when information relating to various reticles R to be sequentially exposed is input via input means 14 such as a keyboard, the input information is transmitted to the control means 13. Is input to This control means 13 provides an optimum line width for various reticles,
Information such as depth of focus is stored in the internal memory,
First exchange means 10, second exchange means, and diameter varying means 12
Control.

The first exchange means 10, the second exchange means and the aperture varying means 12 include a drive system therein.
Based on the control signal from the control means 13, the optimum line width,
Prism members (20, 21) and aperture stops (40, 41) for annular illumination of reticle R with depth of focus
Is selectively set, and the aperture of the aperture stop 6 is set.

A mark such as a bar code including information such as an optimum line width and depth of focus is formed outside the pattern area of the reticle R, and a mark detecting means for detecting the mark is provided by a peripheral portion where the reticle R is set. And the detection information may be directly input to the control means 13. Thus, the prism members (20, 21) are appropriately replaced,
By changing the size of the annular secondary light source formed on the exit side of the fly-eye lens 3 and the annular ratio to change the annular illumination (or oblique illumination) state, the pattern on the reticle R is optimized. It can be transferred onto a wafer under an appropriate line width and depth of focus.

Here, in order to sufficiently bring out the effect of the annular illumination obtained by the above configuration, the fly-eye lens 3
D ₁ the inner diameter of the secondary light source of the annular shape formed on the exit side of,
When the outer diameter of the ring-shaped secondary light source formed on the exit side of the fly-eye lens 3 is d ₂ , the ring zone satisfies 1/3 ≦ d ₁ / d ₂ ≦ 2/3 (1) It is desirable to set the beam diameter. As a result, the depth of focus of the projection optical system is improved, and a practical improvement in resolution is achieved.

If the lower limit of the condition (1) is exceeded, the inner diameter of the annular light source becomes too small, the effect of the annular illumination according to the present invention is weakened, and it is difficult to improve the depth of focus and the resolution of the projection optical system. Becomes Conversely, when the value exceeds the upper limit of the condition (1), the line width transferred onto the wafer differs depending on the presence or absence of the periodicity even on the reticle, even if the pattern has the same line width. Disappears. Further, since the amount of change in the line width with respect to the change in the exposure amount becomes large, it becomes difficult to form a pattern having a desired line width on the wafer.

Furthermore, in order to maximize the effect of the annular illumination of the present invention, the numerical aperture of the reticle R of the projection lens 3 is determined by NA ₁ and the outer diameter of the secondary annular light source. When the numerical aperture of the illumination optical system is NA ₂ , it is desirable that the following condition (2) is satisfied. 0.45 ≦ NA ₂ / NA ₁ ≦ 0.8 (2) When the lower limit of the condition (2) is exceeded, the angle of incidence of light for obliquely illuminating the reticle by the annular illumination is reduced, and the annular illumination according to the present invention is performed. Can hardly obtain the effect of. For this reason, it is meaningless to perform annular illumination.
Conversely, when the value exceeds the upper limit of the condition (2), the resolution as an aerial image is improved, but the depth of focus is reduced. Moreover,
This is not preferable because the contrast at the best focus is greatly reduced.

As described above, in the first embodiment shown in FIG. 1, in order to form an annular parallel light beam, the annular light beam converting member has a concave conical refracting surface on the incident side and a convex surface on the exit side. The prism members (20, 21) having a conical refracting surface and having different axial thicknesses are exchangeably provided.
As shown in FIG. 6, a prism member 20 having convex conical refraction surfaces on the entrance side and exit side (see FIG. 4A), and a conical refraction surface having a different axial thickness from the entrance side and exit side and convex on the entrance side and exit side. May be provided so as to be interchangeable with each other (see FIG. 4B). Furthermore, a prism member having a concave conical refraction surface on the entrance side and a convex conical refraction surface on the exit side, and a prism member having convex conical refraction surfaces on the entrance side and the exit side can be exchanged. May be provided.

In this embodiment shown in FIG. 1, two prism members are provided so as to be interchangeable with each other. However, two or more prism members may be provided so as to be interchangeable. Ordinary lighting may be performed without being inserted into the inside. Next, a second embodiment according to the present invention will be described with reference to FIG. In the present embodiment, the difference from the first embodiment is that the annular light beam conversion unit 2 is constituted by two prism members with variable intervals.
The point is that the annular ratio of the annular parallel light flux is continuously changed. In FIG. 2, members having the same functions as those in FIG. 1 are denoted by the same reference numerals.

As shown in FIG. 2, the orbicular luminous flux conversion unit 2
A first prism member 22 having a concave conical refracting surface on the incident side and having a flat surface on the exit side, and a second prism member 2 having a flat surface on the incident side and having a convex conical refracting surface on the exit side.
The two prisms are provided so as to be movable by an interval varying means 15. The variable interval means 15 includes a drive system, and is controlled by the control means 13 as in the first embodiment shown in FIG.

Here, both prism members (22, 2)
When the interval of 3) is increased, as shown in FIG. 2A, the parallel luminous flux from the light source unit 1 incident thereon becomes an orbicular parallel luminous flux having a small orbital ratio due to an increase in the outer diameter of the orbicular luminous flux. When the distance between the two prism members (22, 23) is reduced, the parallel light beam from the light source unit 1 incident on the prism member (22, 23) has a small outer diameter of the annular light beam, as shown in FIG. As a result, the light is converted into a ring-shaped parallel light beam having a large ring ratio.

Therefore, by appropriately changing the distance between the prism members (22, 23), the size and the annular ratio of the annular secondary light source formed on the exit side of the fly-eye lens 3 are continuously changed. Then, when the annular illumination (or oblique illumination) state is changed, the pattern on the reticle R can be transferred onto the wafer with an optimum line width and focal depth. Note that also in the present embodiment, the above-mentioned condition (1) is satisfied.
It is desirable that the light flux should be an annular luminous flux that satisfies the condition (2).

As shown in FIG. 5A, the first prism member 22 and the second prism member 23 as the orbicular luminous flux conversion section 2 of the present embodiment are arranged with their respective directions reversed. The distance between the two members may be changed. In this case, as shown in FIG. 5B, if the two prism members are brought close to each other until the interval between them completely disappears, normal illumination can be performed.

The shapes of the first and second prism members are not limited to those described above. As shown in FIG. 6, the second prism member has a convex conical refracting surface on the incident side and a flat surface on the exit side. The second prism member may be configured to have a flat surface on the incident side and a convex conical refracting surface on the exit side. Further, as shown in FIG. May be reversed.

Next, a third embodiment of the present invention will be described with reference to FIG. The present embodiment is different from the second embodiment in that an afocal variable power optical system 30 is disposed between two prism members as the orbicular luminous flux conversion unit 2 and the fly-eye lens 3 so as to provide an orbicular luminous flux. Is that the radius (outer diameter) of the orbicular zone light beam is made continuously variable in addition to continuously changing the orbicular zone ratio. In FIG. 3, members having the same functions as those in FIG. 1 are denoted by the same reference numerals.

As shown in FIG. 3, the afocal variable power optical system 30 includes, in order from the light source side, a first group 30a having a positive refractive power;
It is composed of a second group 30b having a negative refractive power and a third group 30b having a positive refractive power. The second group 30b and the third group 30b are
The second group 30b and the third group 30b are moved by the magnification changing means 31. Note that the scaling means 31 includes a drive system, and like the first embodiment shown in FIGS. 1 and 2,
It is controlled by the control means 13.

Here, when the distance between the second group 30b and the third group 30b is increased (maximum magnification state), as shown in FIG. 3A, the annular parallel light flux incident thereon becomes the annular light flux. The light beam is converted into a light beam having a large outer diameter, and
When the distance from the group 30b is reduced (in the minimum magnification state), FIG.
As shown in (B), the annular luminous flux incident thereon is
The annular light beam is converted into a light beam having a small outer diameter.

Accordingly, by appropriately changing the distance between the second group 30b and the third group 30b, that is, by changing the afocal variable power optical system 30, the secondary light source in the form of an annular zone formed on the exit side of the fly-eye lens 3 can be obtained. The outer diameter can be continuously changed, and the annular zone ratio of the annular secondary light source formed on the exit side of the fly-eye lens 3 can be changed by appropriately changing the interval between the prism members (22, 23). It can be changed continuously. Therefore, the annular ratio of the annular secondary light source and the size (outer diameter) of the annular secondary light source can be continuously and independently controlled, so that the optimal annular illumination (or inclined illumination) state can be freely set. The degree improves. As a result, the pattern on the reticle R can be transferred onto the wafer under a more optimal line width and depth of focus. At this time, also in the present embodiment, it is desirable to change the annular luminous flux so as to satisfy the above-described conditions (1) and (2).

It is needless to say that the afocal variable power optical system 30 of the present embodiment can be applied to the embodiments shown in FIGS. FIG. 8 shows an example of a specific switching mechanism of the aperture stop means 4 provided on the exit side of the fly-eye lens 3 of each embodiment shown in FIGS.
This will be described with reference to FIG.

As shown in FIG. 8, on a circular substrate 400, eight types of diaphragms having transmission areas indicated by oblique lines are provided along the circumferential direction.
Is rotatable about O so that one of the stops is located in the illumination light path. On this substrate 400, three kinds of ring-shaped diaphragms having different ring ratios are formed. The diaphragm 401 has a ring-shaped transmission region having a ring ratio of r ₁₁ / r _21. Has a ring-shaped transmission region having a ring ratio of r ₁₂ / r ₂₂ , and the aperture 405 is provided with r ₁₃ / r _21.
Has a ring-shaped transmission region having a ring-shaped ratio of.

A diaphragm for efficiently forming four eccentric light sources under three different ring zone ratios is formed on the substrate 400, and the diaphragm 402 has a ring of r ₁₁ / r ₂₁ . The aperture 404 has four apertures in the luminous flux with an orbital ratio of r ₁₂ / r ₂₂ ,
The diaphragm 406 has four apertures in the annular light flux having an annular ratio of r ₁₃ / r ₂₁ .

[0040] Further, the substrate 400 on the two diaphragm usually circular bore for performing the illumination is formed, the diaphragm 407 has a circular diameter of 2r _22, aperture 408 is 2r _{It has 21} circular apertures. Therefore, if one of the apertures 401, 403, and 405 is selected and positioned in the illumination optical path, annular luminous fluxes having three different annular zone ratios can be accurately defined (restricted), and the apertures 402, 404 can be defined. And 406 are selected and positioned in the illumination optical path, four eccentric light sources can be efficiently formed under three different ring zone ratios. This makes it possible to perform efficient inclined illumination. Also, the aperture 40
If one of 7 and 408 is selected and positioned in the illumination light path, normal illumination with different σ values can be performed.

FIG. 8 illustrates an example of a turret type switching mechanism in which a plurality of diaphragms are provided along the circumferential direction on the circular substrate and the diaphragm is arbitrarily selected. Aperture stop 41 provided in
May not be exchangeable with the aperture stop 42, but may be provided so that the aperture of the aperture stop 41 itself can be changed. Although the fly-eye lens is used as a means for forming the secondary light source in each of the embodiments shown in FIGS. 1 to 3, a rod-shaped optical member (rod-shaped optical integrator) may be used.

[0042]

As described above, according to the present invention, a high-performance illumination device capable of uniformly illuminating a surface to be irradiated with high illumination efficiency by forming an annular secondary light source without any light shielding. Optical devices can be achieved. Moreover, according to the apparatus shown in each of the embodiments, the size of the annular secondary light source and the annular ratio can be varied under high illumination efficiency, so that the pattern on the reticle R can be adjusted to the optimum line width. Can be transferred onto the wafer under a depth of focus.

According to the device shown in the third embodiment,
Since the annular ratio and the size of the annular secondary light source can be independently varied, the degree of freedom in setting the optimal annular illumination (or oblique illumination) state is improved. As a result, the pattern on the reticle R can be transferred onto the wafer under a more optimal line width and depth of focus.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a second embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a third embodiment of the present invention.

FIG. 4 is a view showing a modification of the first and second prism members according to the first embodiment of the present invention.

FIG. 5 is a view showing a first modification of the first and second prism members according to the second embodiment of the present invention.

FIG. 6 is a view showing a second modification of the first and second prism members according to the second embodiment of the present invention.

FIG. 7 is a view showing a third modification of the first and second prism members according to the second embodiment of the present invention.

FIG. 8 is a diagram showing an example of an aperture stop switching mechanism provided on the exit side of the fly-eye lens 3;

[Explanation of Signs of Main Parts]

 DESCRIPTION OF SYMBOLS 1 ... Light source part 2 ... Annular zone light beam conversion part 3 ... Fly-eye lens 4, 6a ... Aperture stop 5 ... Condenser lens 6 ... Projection lens R ... Reticle W ...・ Wafer

[Procedure amendment]

[Submission date] December 17, 1999 (1999.12.
17)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Patent application title: Exposure apparatus and method for manufacturing semiconductor element

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus suitable for semiconductor manufacturing and a method for manufacturing a semiconductor device using the exposure apparatus.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

As a result, there has been a problem that the exposure time is prolonged and a decrease in throughput is unavoidable. The present invention overcomes the above-mentioned problems and provides an exposure apparatus that can form a secondary light source in a ring shape without blocking any light and that can expose a reticle pattern onto a wafer with high illumination efficiency. It is intended to be. Further, the present invention provides a method for manufacturing a good semiconductor device by forming a secondary light source in the form of an annular zone without any light shielding and exposing a reticle pattern to a wafer under high illumination efficiency. It is also aimed at.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007]

To achieve the above object, an exposure apparatus according to the present invention comprises: a light source for supplying exposure light for illuminating a reticle; and a projection for projecting a pattern of the reticle onto a wafer. An exposure apparatus having an optical system, an optical integrator arranged in an optical path of exposure light supplied from the light source means, a means for condensing a light beam from the optical integrator to illuminate a reticle, and the light source means And an annular light beam converting means for converting the exposure light arranged in the optical path of the optical integrator into an annular light beam, and means for changing the outer diameter of the annular light beam from the annular light beam converting means. And the annular light flux converting means changes the diameter of the annular light flux or the annular ratio of the annular light flux. Based on the above configuration, the annular light beam converting means preferably has two or more members provided so as to be insertable into the optical path, and it is more preferable that each of the two or more members has a conical refraction surface. preferable. Alternatively, based on the above configuration, the orbicular luminous flux converting means may have two members with variable intervals, and at this time, it is desirable that each of the two or more members has a conical refraction surface.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

Further, it is preferable that the light source means has a laser light source, and it is more preferable that the light source means has a beam expander for shaping light from the laser light source. In this case, the laser light source is
An excimer laser light source is even more desirable. Preferably, the optical integrator has a rod-shaped optical member. Further, in a method of manufacturing a semiconductor device according to the present invention, the pattern of the reticle is transferred to the wafer by using the above exposure apparatus.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

Further, another method of manufacturing a semiconductor device according to the present invention is a method of manufacturing a semiconductor device, comprising the steps of illuminating a reticle with exposure light and projecting the reticle pattern onto a wafer. The step of illuminating the reticle has a step of converting the exposure light into an annular light flux to vary the annular ratio of the annular light flux, and a step of varying the outer diameter of the annular light flux. It was done. In another method for manufacturing a semiconductor device according to the present invention as described above, the step of varying the annular ratio of the annular light flux and the step of varying the outer diameter of the annular light flux include the annular zone of the annular light flux. It is preferable that the ratio and the outer diameter of the annular light beam be independently variable.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

Preferably, the step of changing the annular ratio of the annular light flux includes a step of inserting one of the two or more members into an optical path. More preferably, each of the steps of inserting one of the two into the optical path has a conical refractive surface. Alternatively, the step of changing the annular ratio of the annular luminous flux may include a step of changing an interval between two members. In this case, the step of changing the interval between the two members may include: More preferably, it has a conical refractive surface. Further, the step of illuminating the reticle with the exposure light preferably includes a step of supplying light from a laser light source as the exposure light. In this case, the light from the laser light source is beam-shaped using a beam expander. It is more desirable to have a step. Further, it is more preferable that the step of illuminating the reticle with the exposure light includes a step of guiding the illumination light to the reticle via a rod-shaped optical integrator.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

[0011]

In the device according to the present invention, the light flux (almost parallel light flux such as laser light) from the light source is shielded at all by the refraction of the annular light flux conversion means (a convex conical refraction surface or a concave conical refraction surface). Zonal luminous flux (parallel zonal luminous flux)
As a result, a ring-shaped secondary light source can be formed by the optical integrator. Therefore, since the reticle as the irradiated surface can be uniformly illuminated under high illuminance, the resolution and the depth of focus of the projection optical system (projection lens) can be improved without lowering the throughput.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

Further, for example, the annular light beam converting means has a plurality of members having a convex conical refracting surface or a concave conical refracting surface, and the plurality of members can be exchanged or the plurality of members can be replaced. By providing a variable interval,
Under high illumination efficiency, annular luminous flux (annular parallel luminous flux)
The ratio of the inner diameter to the outer diameter, that is, the so-called annular zone ratio, can be changed. Accordingly, since a secondary light source having an arbitrary ring zone ratio can be formed, the pattern on the reticle R can be formed with an optimum line width,
It can be transferred onto a wafer under a depth of focus.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction contents]

Further, if an afocal variable power optical system is provided in the illumination optical system as means for varying the diameter (outer diameter) of the annular light beam by changing the power, the variable power of the afocal variable power optical system is provided. Thus, the diameter (outer diameter) of the orbicular luminous flux (orbicular parallel luminous flux) can be varied while maintaining the orbicular zone ratio constant. Therefore, since the diameter (outer diameter) of the orbicular light beam can be changed without changing the orbicular ratio by the afocal variable power optical system, the orbicular ratio and the diameter (outer diameter) of the orbicular light beam can be controlled independently.

Claims (4)

[Claims] 1. A light source means for supplying a substantially parallel light beam, an optical integrator for forming a plurality of secondary light sources by the parallel light beams from the light source means, and a plurality of secondary light sources formed by the optical integrator. An illumination optical device having a condenser lens that condenses a light beam from a light source and illuminates a surface to be irradiated in a superimposed manner. An illumination optical apparatus, comprising: an annular light beam converting means for converting light; wherein the annular light beam converting means includes an optical member having a conical refraction surface. 2. The optical member according to claim 1, wherein the first member has a conical refractive surface.
The illumination optical device according to claim 1, further comprising: a second refraction member; and one of the first and second refraction members is provided so as to be inserted into the parallel optical path. 3. The optical member has first and second refraction members having conical refraction surfaces, and the first and second refraction members are variably provided with a relative distance, and the distance is changed. The illumination optical device according to claim 1, wherein the diameter of the annular light beam is made variable by causing the diameter of the annular light beam to change. 4. An afocal variable power optical system is provided between the annular light beam converting means and the optical integrator, and the outer diameter of the annular light beam is made variable by changing the power of the afocal variable optical system. The illumination optical device according to claim 1, wherein: