JPH11260708A - Projection exposure apparatus and semiconductor device manufacturing method using the apparatus - Google Patents

Abstract

(57) [Problem] To provide a projection exposure apparatus capable of easily obtaining an optimal light beam shape for various illumination aperture stops. SOLUTION: A light source unit 1 for supplying illumination light, a light beam conversion member 4b for converting the illumination light from the light source unit into a predetermined light beam cross-sectional shape, and a number of light sources based on the illumination light via the light beam conversion member. Main optical integrator 13 that forms
A main condenser optical system 9 for condensing light from a number of light sources formed by the main optical integrator to illuminate the mask; and a light beam converting member for changing the illumination state of the illumination light for illuminating the mask. And a main optical integrator. The optical unit UT is detachably provided between the optical unit and the main optical integrator. The optical unit converts a light beam cross-sectional shape of the illumination light via the light beam converting member into illumination light having a predetermined light beam cross-sectional shape. I do.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection exposure apparatus, particularly a projection exposure apparatus used for forming a pattern for a semiconductor integrated circuit or a liquid crystal device, and an LSI using the apparatus.
The present invention relates to a method for manufacturing a semiconductor device such as a liquid crystal or a CCD.

[0002]

2. Description of the Related Art In general, a conventional projection exposure apparatus for manufacturing a semiconductor element or a liquid crystal device illuminates an original plate called a reticle or mask on which a predetermined pattern is formed with illumination light (exposure light) having uniform illuminance. Then, the pattern of the original plate is projected and exposed on a photosensitive substrate such as a wafer or a glass plate coated with a photoresist. FIG. 5 is a diagram showing a configuration of an optical system of a conventional projection exposure apparatus. First of elliptical mirror 2
A light beam from a short arc type (ultra-high pressure) mercury lamp (Hg lamp, Xe-Hg lamp, etc.) 1 disposed at the focal position is reflected by a mirror 3 and then substantially parallel to the optical axis by a lens 4a. Is converted to Then, the light enters a wavelength selection filter 5 which is a bandpass filter. The light beam whose wavelength has been selected by passing through the wavelength selection filter 5 enters the optical integrator 6. The optical integrator 6 divides the incident wavefront and forms a secondary light source image near the exit surface of the optical integrator 6. The secondary light source surface, which is the collective surface of the secondary light source images,
An aperture stop is provided for determining illumination conditions such as the resolution of the pattern or the depth of focus. Conventionally, an illumination aperture stop for determining illumination conditions has been fixed to one.
Recently, various conditions have been required for the resolution of the pattern, the depth of focus required in the exposure step, and the like. For this reason, for example, Japanese Unexamined Patent Publication No. 59-15584
As disclosed in Japanese Unexamined Patent Publication No. 3 (1999) -1995, a mechanism capable of switching between illumination aperture stops having various aperture shapes has also been proposed. For example, as shown in FIG. 6, aperture stops 7a to 7c for determining the illumination condition of the reticle 10 are arranged on the revolver 7 so as to be selectively switched. Here, the aperture 7a is a circular aperture, 7b is an annular aperture, and 7c is a four-pole (fourth) aperture. By appropriately selecting the illumination aperture stops 7a to 7c, it is possible to change a coherency factor of illumination light, a so-called σ value. The σ value is a value obtained by dividing the size of the secondary light source on the exit side of the optical integrator 6 by the size of the pupil of the projection optical system 11. For example, σ
= 0, coherent illumination, 0 <σ <1, partial coherent illumination, and σ = ∞, incoherent illumination. As described above, the σ value can be changed by selecting the aperture, and the resolution or the depth of focus at the time of exposure can be changed. Therefore, by appropriately selecting an aperture stop according to the pattern shape to be projected and exposed, it is possible to perform projection exposure under optimum conditions. In general, in a photolithography process for manufacturing a semiconductor device, the σ value is equal to 0.3.
It is about 3 to 0.8. The light beams that have passed through the aperture stops 7a to 7c are superimposed on a reticle 10, which is a surface to be irradiated, by a condenser lens 9 to perform uniform illumination of the reticle. The pattern formed on the illuminated reticle 10 is projected and exposed on a wafer 12 via a projection optical system 11.

[0003]

As described in the above prior art, the illumination aperture stop has various aperture shapes.
Therefore, when the light beam cross-sectional shape of the illumination light is circular,
When the aperture 7b for annular illumination or the aperture 7c for quadrupole illumination is selected, a part of the circular illumination light is blocked. Therefore, it is not preferable because inconveniences such as a decrease in the amount of exposure light, a prolonged exposure time, and a decrease in throughput occur. Conventionally, in order to avoid such inconveniences and to minimize the loss of light amount by adjusting the shape of the illumination light in the optical integrator 6 to the shape of the illumination aperture stop, a light transmission optical system from the light source 1 to the optical integrator 6 is provided. The variable magnification relay lens is arranged so that it can be inserted and removed. This is to insert a variable power relay lens into the light beam so as to increase or decrease the diameter of the circular light beam, thereby minimizing the portion blocked by the illumination aperture stop. However, in the insertion / removal / magnification switching of the variable power relay lens system provided in the light transmission optical system, only the diameter of the cross-sectional shape of the luminous flux of the illumination light can be changed. Therefore, the shape of the illumination light cannot be changed efficiently. For this reason, in a projection exposure apparatus that selectively uses a circular aperture, an annular aperture, a quadrupole aperture, and the like, there is a problem that efficient illumination corresponding to each aperture cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a projection exposure apparatus capable of easily obtaining an optimum light beam shape for various illumination aperture stops and efficiently illuminating a reticle and the like. It is an object of the present invention to provide a method of manufacturing a semiconductor device.

[0005]

According to the first aspect of the present invention, an illumination optical system (2-9) for illuminating a mask (10) on which a predetermined pattern is formed is provided.
And illuminating the pattern of the mask with a photosensitive substrate (12).
In a projection exposure apparatus that performs projection exposure on a light source, a light source unit (1) that supplies illumination light, a light beam conversion member (4b) that converts the illumination light from the light source unit into a predetermined light beam cross-sectional shape, and the light beam conversion member A main optical integrator (6) for forming a plurality of light sources based on illumination light passing through the main condenser integrator for condensing light from the plurality of light sources formed by the main optical integrator and illuminating the mask A system (9), and an optical unit (UT) that is detachably provided between the light beam conversion member and the main optical integrator to change an illumination state of the illumination light that illuminates the mask. The optical unit converts the light beam cross-sectional shape of the illumination light via the light beam converting member into illumination light having a predetermined light beam cross-sectional shape.

Further, in the invention according to claim 2, the optical unit is formed by an auxiliary optical integrator (13) for forming a number of light sources based on illumination light passing through the light beam converting member, and the auxiliary optical integrator. And an auxiliary condenser optical system (14) for condensing the light from the multiple light sources and guiding the collected light to the main optical integrator.

According to the third aspect of the present invention, the light beam converting member has a plurality of optical axes decentered with respect to the optical axis of the illumination optical system based on the illumination light from the light source unit. Alternatively, it is characterized in that the light is converted into illumination light having an annular light flux cross section.

According to a fourth aspect of the present invention, the illumination optical system includes a main optical integrator disposed on an exit surface side of the main optical integrator in response to a change in an illumination state of the illumination light for illuminating the mask. The aperture stop has aperture stop means (7a, 7b, 7c) for changing the shape or size of a large number of light sources formed by the integrator, and a first driving device (MT) for driving the aperture stop means. The means includes an annular aperture stop (7b) and a circular aperture stop (7b).
a) and the illumination optical system further comprises:
The optical unit is inserted into the illumination optical path when the circular aperture stop is set in the illumination optical path via the first driving device, and the annular aperture stop is connected to the illumination optical path via the first driving device. And a second driving device (MV) for retracting the optical unit out of the illumination light path when set inside.

Further, according to the invention of claim 5, according to claim 1,
A method for manufacturing a semiconductor device using the projection exposure apparatus according to any one of claims 1 to 4, wherein the step of setting the mask (10) on an object plane of the projection optical system (11); Setting a substrate (12) on the image plane of the projection optical system (11); and projecting a pattern of the mask (10) through the projection optical system (11).
2) a step of exposing on top.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. (First Embodiment) FIGS. 1A and 1B are views showing an outline of an optical system of a projection exposure apparatus according to an embodiment of the present invention. In FIG. 1A, a short arc type (ultra high pressure) mercury lamp (H
A light beam from a g lamp, a Xe-Hg lamp, etc.) 1 is reflected by a mirror 3 and then converted by a collector lens 4a into a light beam substantially parallel to the optical axis. Then, after the luminous flux cross-sectional shape of the illumination light from the light source 1 is converted into an annular shape by the cone prism 4b, in order to match the achromatic condition range of the illumination optical system and the imaging optical system using the illumination light, The light enters the wavelength selection filter 5. The light beam whose wavelength has been selected by passing through the wavelength selection filter 5 enters the main optical integrator 6. Here, in the present embodiment, as shown in FIG. 1B described later, between the wavelength selection filter 5 and the main optical integrator 6, the auxiliary optical integrator 13 housed in the optical unit UT and the auxiliary condenser lens 14 are configured to be insertable into and removable from the light beam by the driving device MV. FIG.
(A) shows a state in which the optical unit UT is out of the position IN in the illumination light path and is at the retreat position OUT.

The main optical integrator 6
Divides the incident wavefront and forms a secondary light source image near the exit surface of the main optical integrator 6. Aperture stops 7a to 7c for determining illumination conditions are provided on the secondary light source surface, which is a collective surface of the secondary light source images. As shown in FIG. 6, these aperture stops are arranged on a revolver 7 such that a circular aperture stop 7a, an annular aperture stop 7b, and a 4-pole aperture stop 7c for determining an illumination condition of the reticle 10 can be selectively switched. I have. Then, the revolver 7 is rotated by the motor MT, and can move a desired aperture stop into the illumination optical path.
By appropriately selecting the illumination aperture stops 7a to 7c, the coherency factor (σ value) of the illumination light can be changed, as described in the above-described related art. In the present embodiment, the σ value is preferably about 0.3 to 0.8. The luminous flux that has passed through the aperture stops 7a to 7c is transmitted by the main condenser lens 9 to the reticle 1 that is the surface to be irradiated.
0, superimpose on 0 to uniformly illuminate the reticle. The illuminated reticle pattern is projected and exposed on a wafer 12 via a projection optical system 11. In the projection exposure apparatus, the entrance surface of the main optical integrator 6, the reticle 10 and the wafer 12 have a conjugate relationship with each other, and the aperture stops 7a to 7c and the pupil of the projection lens 11 have a conjugate relationship. It is configured.

As shown in FIG. 1A, when the auxiliary optical integrator 13 and the auxiliary condenser lens 14 are at the retracted position OUT, the shape of the light beam incident on the main optical integrator 6 is changed by the action of the cone prism 4b. It has a band shape. Therefore, when the annular aperture stop 7b is selected, the reticle 10 can be efficiently illuminated because there are few portions shielded by the aperture stop. Therefore, projection exposure can be performed in a minimum exposure time.

After a series of projection exposure processes using the reticle 10 is completed, if another reticle is to be replaced and further projection exposure is performed, the projection exposure is performed in accordance with the type of the reticle pattern as described above. Often it is necessary to change the resolution or the depth of focus. For example, after the projection exposure by the annular aperture stop 7b shown in FIG.
Further, consider a case where projection exposure is performed using the circular aperture stop 7a. In a state where the auxiliary optical integrator 13 and the auxiliary condenser lens 14 are at the retracted position OUT as shown in FIG. 1A, the shape of the light beam incident on the main optical integrator 6 is an annular shape by the cone prism 4b. In this state, the lighting efficiency is not good.
Therefore, as shown in FIG. 1B, the drive unit MV moves the optical unit UT containing the auxiliary optical integrator 13 and the auxiliary condenser lens 14 from the retreat position OUT to the position IN, thereby causing the unit to move. UT
Into the illumination light path. As a result, by the action of the auxiliary optical integrator 13, the annular light beam can be converted into a circular light beam. Further, the auxiliary condenser lens 14 has a role of appropriately illuminating the light beam transmitted through the auxiliary optical integrator 13 onto the incident surface of the main optical integrator 6. As described above, by inserting the optical unit UT into the position IN in the illumination optical path when the circular aperture stop 7a is selected, the light beam that has passed through the wavelength selection filter 5 is converted into a circular shape, and then converted into the main optical integrator. 6 is incident. Next, the incident light beam is split by the main optical integrator 6 to form a secondary light source image near the exit of the main optical integrator 6. On the secondary light source surface, which is a collective surface of the secondary light source images, there is an illumination circular aperture stop 7a for determining the illumination conditions. At this time, since the light beam cross-sectional shape of the illuminating light is made circular by the auxiliary optical integrator and then enters the circular aperture stop 7a, there is almost no loss of light amount due to the light beam being cut off by the stop. The luminous fluxes of a plurality of secondary light sources that have exited the illumination circular aperture stop 7a are transmitted by the main condenser lens 9 to the reticle 1 that is the surface to be irradiated.
0 is superimposed. The illuminated reticle pattern is projected and exposed on a wafer 12 via a projection optical system 11. Here, it is more preferable to optimize the size and arrangement of the projection exposure apparatus by using a reflecting mirror using a dielectric film or the like.

As described above, in the first embodiment, in the state where the circular illumination aperture stop 7a is selected, FIG.
As shown in (B), the driving device MV moves the optical unit UT from the retreat position OUT to a position IN in the illumination light path.
Thereby, the auxiliary optical integrator 13 and
An auxiliary condenser lens 14 for appropriately illuminating the light beam from the integrator 13 onto the main optical integrator 6 is inserted in the illumination optical path, and the light beam optimized for an illumination aperture stop such as annular illumination until immediately before the auxiliary optical integrator 13. Can be appropriately illuminated in accordance with the shape of the circular illumination aperture stop 7a.

The light source is not limited to the above-described mercury lamp 1 or the like, but may be an excimer laser or the like. When the excimer laser 1 'is used as a light source as shown in FIG. 2, it is preferable to use a beam shaping lens BL instead of the collector lens 4a to perform beam shaping and relay a light source image.

Although the cone prism 4b is used as a light beam converting member for making the cross section of the light beam of the illumination light into an annular shape, the present invention is not limited to this prism. An opening may be used, and the end face on the emission side may be formed in an annular shape.

In the above embodiment, the optical unit U
By inserting T at the position IN in the illumination optical path, the light beam cross-sectional shape is converted from the annular shape to the circular shape, but the present invention is not limited to such conversion. As a light beam conversion member, an element that performs illumination of a plurality of lights decentered with respect to the optical axis AX of the illumination optical system, for example, an element that performs quadrupole illumination is used, and when the optical unit UT is in the retracted position OUT, quadrupole illumination (ie, 4 Optimal illumination may be performed when the extreme aperture stop 7c is selected. In this case, the circular aperture stop 7a
Is selected, the optical unit UT is inserted into the position IN in the illumination optical path to convert the quadrupole illumination light beam into a circular light beam, so that the circular aperture stop 7a can be efficiently illuminated. In the case of performing quadrupole illumination, as the light beam conversion member, a prism whose entrance surface and exit surface are each a quadrangular pyramid (pyramid shape) surface, or an optical fiber bundle whose entrance end surface is circular but whose exit end surface is 4 It is preferable to use one in which the fiber bundle is branched into two circular shapes (corresponding to the opening of the stop 7c).

In this embodiment, by rotating the revolver 7 by the motor MT, predetermined aperture stops 7a to 7
Although c is moved into the illumination light path, in addition to this, for example, a configuration in which various aperture stops can be inserted into the illumination light path by a driving mechanism such as a motor may be used.

(Second Embodiment) In the projection exposure apparatus of the first embodiment, among the aperture stops provided in the revolver 7, only one aperture stop 7a has a circular shape.
The projection exposure apparatus according to the second embodiment selectively uses circular openings of various sizes in addition to the annular shape and the like.
The basic configuration of the apparatus is the same as that of the projection exposure apparatus according to the first embodiment, and a description thereof will be omitted. FIG. 3 is a diagram showing a relationship among auxiliary optical integrators 13a to 13d, auxiliary condenser lenses 14a to 14d, and aperture stops 7a to 7b in the optical unit UT of the projection exposure apparatus according to the present embodiment. Here, the auxiliary optical integrator is provided on the revolver 13 'so that a plurality of auxiliary optical integrators 13a to 13d having different focal lengths can be selectively switched. In addition, the auxiliary condenser lens 14 has a different focal length.
a to 14d are provided on the revolver 14 'so as to be selectively switchable. Further, the illumination aperture stop is similarly provided with a revolver 7 'that can selectively switch between the circular aperture stops 7a, 7a', 7a "and the annular aperture stop 7b having different aperture diameters.
It is provided above. For simplicity, in FIG.
Main optical integrator 6 and each revolver 1
A motor MT as a drive mechanism for rotating 3 ′, 14 ′, and 7 ′ is omitted. A revolver 13 'provided with a plurality of auxiliary optical integrators and a revolver 1 provided with a plurality of auxiliary condenser lenses are provided.
4 ′ is housed in the optical unit UT and includes the driving device MV
With this arrangement, it is possible to integrally move between the position IN in the illumination optical path and the retracted position OUT (not shown).

Next, the auxiliary optical integrator 1
3a to 13d, auxiliary condenser lenses 14a to 14
The optimum combination of d and the aperture stops 7a to 7b will be described.

The focal length of the auxiliary optical integrator 13a and the like is foi, the effective diameter of each element lens constituting the auxiliary optical integrator 13a and the like is φ, the focal length of the auxiliary condenser lens 14a and the like is fcl, and the focal length of the main optical integrator 6 is Assuming that the effective diameter of the illumination area is Ф, the following equation (1) and Φ = φ × (fcl / foi) (1) are satisfied. That is, the effective diameter 照明 of the illumination area on the main optical integrator 6 is equal to the auxiliary condenser lens 1
4a is proportional to the ratio between the focal length fcl of the auxiliary optical integrator 13a and the focal length fcl of the auxiliary optical integrator 13a.

Therefore, when a circular aperture stop having an aperture diameter Φ is selected, if a combination of an auxiliary optical integrator and an auxiliary condenser lens that satisfies the expression (1) is selected, the σ value can be changed easily and efficiently. A circular aperture stop can be illuminated.

FIG. 3 shows an auxiliary optical integrator 13c (effective diameter φ of each element lens, focal length foi),
FIG. 14 is a diagram showing a state where an auxiliary condenser lens 14c (focal length fcl) and an aperture stop 7a ″ (effective diameter Φ) are selected and inserted on the optical axis AX of the illumination optical system.

(Third Embodiment) Next, an example of an operation when a predetermined circuit pattern is formed on a wafer using the projection exposure apparatus of the above embodiment will be described with reference to the flowchart of FIG. In step 1 of FIG. 4, a metal film is deposited on one lot of wafers. In the next step 2, a photoresist is applied to the metal film on the one lot wafer. Then, in step 3, the first
Using the projection exposure apparatus of FIG. 1 having the projection optical system of the embodiment (FIG. 1), the image of the pattern on the reticle 10 is transferred via the projection optical system 11 onto the wafer of one lot of the lot.
Exposure transfer is sequentially performed on each shot area of No. 2. Then, in step 4, after the photoresist on the one lot of wafers is developed, in step 5, etching is performed on the one lot of wafers using the resist pattern as a mask, thereby forming a pattern on the reticle R. Is formed in each shot area on each wafer. Thereafter, a device such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer and the like.

At this time, the projection optical system of this embodiment can use the illumination light efficiently even if the aperture stop for illumination is changed, so that the reticle pattern can be projected and exposed on the wafer in a short exposure time. Therefore, devices such as semiconductors can be manufactured with high throughput.

It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted without departing from the gist of the present invention.

[0027]

As described above, according to the first aspect of the present invention, in order to change the illumination state of the illumination light for illuminating the mask, the illumination light is inserted between the light beam conversion member and the main optical integrator. The optical unit includes a detachable optical unit, and the optical unit converts the light beam cross-sectional shape of the illumination light via the light beam converting member into illumination light having a predetermined light beam cross-sectional shape. Therefore, even when an aperture stop having a different aperture shape is selected, a reticle or the like can be illuminated without loss of illuminance. Therefore, the throughput can be improved by the optimal exposure light amount.

In the invention according to claim 2, the optical unit has an auxiliary optical integrator and an auxiliary condenser optical system. Therefore, the illumination light beam split by the auxiliary optical integrator can be efficiently guided to the main optical integrator.

Further, in the invention according to claim 3, the light beam converting member includes an illumination light having a plurality of lights decentered with respect to an optical axis of the illumination optical system based on the illumination light from the light source unit. The light is converted into illumination light having an annular light flux cross section. Therefore, illumination light of various shapes can be obtained, and illumination conditions such as a value can be easily changed.

According to a fourth aspect of the present invention, when the illumination optical system includes aperture stop means having at least a ring-shaped aperture stop and a circular aperture stop, and the circular aperture stop is set in an illumination optical path. The optical unit is inserted into the illumination optical path, and the optical unit is retracted outside the illumination optical path when the annular aperture stop is set in the illumination optical path. Therefore, when illumination is performed by selecting a circular aperture stop, illumination can be efficiently performed by inserting the optical unit into the illumination optical path.

According to the fifth aspect of the present invention, there is provided the first aspect.
A semiconductor device is manufactured using the projection exposure apparatus according to any one of (1) to (4). Therefore, illumination conditions according to the mask pattern can be obtained quickly and efficiently without loss of illumination light, and a semiconductor device can be manufactured with high throughput.

[Brief description of the drawings]

FIGS. 1A and 1B are views showing a projection exposure apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing an optical system near a light source when an excimer laser is used.

FIG. 3 is a diagram showing a combination of an auxiliary optical integrator, an auxiliary condenser lens, and an aperture stop.

FIG. 4 is a diagram showing a procedure of a semiconductor device manufacturing method according to an embodiment of the present invention.

FIG. 5 is a view showing a conventional projection exposure apparatus.

FIG. 6 is a diagram illustrating an aperture stop.

[Explanation of symbols]

 Reference Signs List 1 Mercury lamp 2 Elliptic mirror 4a Collector lens 4b Cone prism 5 Wavelength selection filter 6 Main optical integrator 7 Revolver 7a to 7c Illumination aperture stop 9 Condenser lens 10 Reticle 11 Projection optical system 12 Wafer 13 Auxiliary optical integrator 14 Auxiliary condenser lens UT optical Unit OUT Retreat position outside light flux IN Insertion position inside light flux MV drive MT motor

Claims (5)

[Claims] An illumination optical system for illuminating a mask on which a predetermined pattern is formed, and a projection exposure apparatus for projecting and exposing the illuminated mask pattern on a photosensitive substrate, a light source unit for supplying illumination light, A light beam conversion member that converts illumination light from the light source unit into a predetermined light beam cross-sectional shape; a main optical integrator that forms a large number of light sources based on the illumination light passing through the light beam conversion member; A main condenser optical system for condensing light from a large number of light sources to illuminate the mask; and for changing an illumination state of the illumination light for illuminating the mask, the light beam converting member and the main optical. An optical unit provided so as to be insertable into and removable from the integrator, wherein the optical unit cuts off a light beam of the illumination light via the light beam converting member. A projection exposure apparatus for converting a surface shape into illumination light having a predetermined light beam cross-sectional shape. 2. The optical unit according to claim 1, wherein the auxiliary optical integrator forms a plurality of light sources based on illumination light passing through the light beam converting member, and collects light from the plurality of light sources formed by the auxiliary optical integrator. 2. The projection exposure apparatus according to claim 1, further comprising an auxiliary condenser optical system that guides the light to the main optical integrator. 3. The illumination device according to claim 1, wherein the light beam conversion member is an illumination light having a plurality of light beams decentered with respect to an optical axis of the illumination optical system or an illumination light beam having an annular light beam cross section, based on the illumination light from the light source unit. 3. The projection exposure apparatus according to claim 1, wherein the light is converted into light. 4. The illumination optical system includes: a plurality of light sources formed by the main optical integrator on an emission surface side of the main optical integrator in accordance with a change in an illumination state of the illumination light for illuminating the mask. Aperture stop means for changing the shape or size of the aperture stop; and a first driving device for driving the aperture stop means. The aperture stop means has at least an annular aperture stop and a circular aperture stop. The illumination optical system further includes: inserting the optical unit into the illumination optical path when the circular aperture stop is set in the illumination optical path via the first driving device;
2. The device according to claim 1, further comprising a second driving device that retracts the optical unit to outside the illumination optical path when the annular aperture stop is set in the illumination optical path via the driving device.
4. The projection exposure apparatus according to 2 or 3. 5. A method of manufacturing a semiconductor device using the projection exposure apparatus according to claim 1, wherein the step of setting the mask on an object plane of the projection optical system; Manufacturing a semiconductor device, comprising: setting a photosensitive substrate on an image plane of the projection optical system; and exposing the pattern of the mask onto the photosensitive substrate via the projection optical system. Method.