JP2001135560A - Illuminating optical device, exposure, and method of manufacturing micro-device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illumination optical device for adjusting the size of an illuminated region on an irradiated face and illumination (NA) to a desired level while a loss in light quantity is reduced adequately. SOLUTION: An illuminated face is irradiated by an illumination optical device. The illumination optical device includes a first variable magnification optical system 4 with variable focal distance or magnification for adjusting the number of illumination openings on the illuminated face, and a second variable magnification optical system 7 with variable focal distance or magnification for changing the size of the illumination region formed on the illuminated region.

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 provided with the illumination optical apparatus. The present invention relates to an illumination optical device suitable for an exposure apparatus.

[0002]

2. Description of the Related Art In a typical exposure apparatus of this kind,
A light beam emitted from the light source enters an optical integrator such as a micro fly's eye, for example, and forms a secondary light source composed of a large number of light source images on a rear focal plane. The luminous flux from the secondary light source is restricted via an aperture stop arranged near the secondary light source, and then enters the condenser lens. The aperture stop limits the shape or size of the secondary light source to a desired shape or size according to a desired illumination condition (exposure condition). The light beam condensed by the condenser lens forms a rectangular illumination field on a predetermined surface conjugate with the mask. A mask blind as an illumination field stop is arranged near the predetermined surface.

Accordingly, the light beam from the rectangular illumination field formed on the predetermined surface is restricted via the illumination field stop, and then illuminated in a superimposed manner on the mask on which the predetermined pattern is formed via the relay lens. I do. Thus, on the mask,
An image of the opening of the illumination field stop is formed as a rectangular illumination area. Light transmitted through the pattern of the mask forms an image on the wafer via the projection optical system. Thus, the mask pattern is projected and exposed (transferred) on the wafer. The pattern formed on the mask is highly integrated, and it is indispensable to obtain a uniform illuminance distribution on the wafer in order to accurately transfer this fine pattern onto the wafer.

In recent years, the size of a secondary light source formed via an optical integrator has been changed by changing the size of an opening (light transmitting portion) of an aperture stop arranged on the emission side of the optical integrator. A technique for changing the illumination coherency σ (σ value = aperture stop diameter / pupil diameter of the projection optical system, or σ value = exit side numerical aperture of the illumination optical system / incident side numerical aperture of the projection optical system). Is attracting attention. Also, the shape of the secondary light source formed by the optical integrator is formed by setting the shape of the aperture of the aperture stop arranged on the emission side of the optical integrator to a ring shape or a four-hole shape (ie, quadrupole shape). Attention has been paid to a technique for improving the depth of focus and the resolving power of a projection optical system by limiting the shape to an annular shape or a quadrupole shape.

[0005]

In an exposure apparatus, it is desired to change the size of an illumination area, that is, an exposure area formed on a photosensitive substrate such as a wafer, according to the characteristics of a microdevice to be manufactured. There is. In other words, there is a case where it is desired to change the size of the illumination area formed on the mask according to the characteristics of the mask to be used. For example, when it is desired to form an illumination area smaller than a standardly set illumination area, a method of reducing the size of the aperture of the illumination field stop described above is conceivable. However,
In this method, light loss occurs in the illumination field stop,
As a result, the throughput of the exposure apparatus decreases.

On the other hand, in order to substantially avoid light loss in the illumination field stop, the illumination area formed on the mask by changing the magnification of the relay lens and the exposure area formed on the photosensitive substrate, for example, are changed. It is also conceivable to reduce the value. However, in this method, the illumination numerical aperture (hereinafter, referred to as “illumination NA”) changes with the change in the size of the illumination area formed on the mask, and the σ value that is optimally designed also changes. Resulting in.

As described above, in the exposure apparatus, there is a demand to set the σ value to a desired value as well as the size of the exposure area according to the characteristics of the microdevice to be manufactured. In other words, in the illumination optical device used in the exposure apparatus, there is a demand to set the illumination NA to a desired value as well as the size of the illumination area, depending on the characteristics of the mask used. The microdevice referred to in the present invention includes a semiconductor element having a semiconductor integrated circuit and the like, a high-definition flat panel display, an imaging element such as a CCD, a magnetic head for a personal computer hard disk, a diffractive optical element, and the like.

In order to change the exposure condition or the illumination condition, a light intensity distribution of the secondary light source formed by the optical integrator (light intensity distribution formed at or near the pupil position of the exposure illumination device) is desired. (For example, any one of a circular shape, a ring shape or a quadrupole shape) or a desired size (for example, a circular shape, a ring shape or a quadrupole shape), However, the illumination numerical aperture (NA) of the mask changes, and it is impossible to expose a good mask pattern to a photosensitive substrate such as a wafer under a desired exposure condition or a desired illumination condition.

The present invention has been made in view of the above-mentioned problems, and adjusts the size of the illumination area formed on the surface to be irradiated and the illumination NA to desired values, respectively, while favorably suppressing the light quantity loss. It is a first object of the present invention to provide an illumination optical device capable of performing the above, an exposure device provided with the illumination optical device, and a microdevice manufacturing method using the exposure device. Further, the present invention provides an exposure apparatus and a micro device capable of exposing a good mask pattern on a photosensitive substrate such as a wafer under a desired exposure condition or a desired illumination condition even if the exposure condition or the illumination condition is changed. It is a second object of the present invention to provide a manufacturing method of the above.

[0010]

According to a first aspect of the present invention, there is provided an illumination optical device for illuminating a surface to be illuminated, wherein an illumination numerical aperture on the surface to be illuminated is adjusted. A first variable power optical system having a variable focal length or magnification, and a second variable power optical system having a variable focal length or magnification for changing the size of an illumination area formed on the irradiation surface.
There is provided an illumination optical device including a variable power optical system.

According to a preferred aspect of the first invention, in order to set the illumination numerical aperture and the size of the illumination area to desired values, respectively, the first variable power optical system and the second variable power optical system are used. It is preferable to provide an adjustment system for adjusting each focal length or each magnification.

According to a preferred aspect of the first invention,
Light source means for supplying illumination light, multiple light source forming means for forming a large number of light fluxes based on the illumination light, and a light source means for converting the light flux from the light source means into a light flux having a predetermined cross-sectional shape A light-flux conversion optical system, wherein the first variable-power optical system guides the light beam passing through the light-flux conversion optical system to the multiple light source forming unit, and the second variable-power optical system includes Is preferably guided to the surface to be irradiated.

In this case, the multiple light source forming means has a wavefront splitting type optical integrator, and the first variable power optical system converts the divergent light beam formed through the light beam conversion optical system into a substantially parallel light beam. To the incident surface of the wavefront splitting optical integrator, and the adjustment system adjusts the second magnification in order to adjust the size of the illumination area formed on the irradiated surface to a desired value. The focal length of the first variable power optical system is adjusted by changing the focal length of the optical system and adjusting the illumination numerical aperture that changes with the change of the focal length of the second variable power optical system to a desired value. Preferably, it is changed.

Alternatively, the multiple light source forming means has an internal reflection type optical integrator, and the first variable power optical system converts the divergent light beam formed through the light beam conversion optical system to the internal reflection type light beam. The light is focused near the entrance surface of the optical integrator, and the adjustment system adjusts the magnification of the second variable power optical system to adjust the size of the illumination area formed on the irradiation surface to a desired value. Preferably, the magnification of the first variable power optical system is changed in order to adjust the illumination numerical aperture, which changes with the change of the magnification of the second variable power optical system, to a desired value.

According to a preferred aspect of the first invention,
A light source unit for supplying illumination light; and a light beam conversion optical system for converting a light beam from the light source unit into a light beam having a predetermined cross-sectional shape. A light beam from an optical system is guided to the second variable power optical system, and the second variable power optical system forms a plurality of light sources for forming a large number of light beams based on the light beam passing through the first variable power optical system. It is preferable that the second variable power optical system includes means for guiding a light beam from the first variable power optical system to the irradiated surface.

In this case, the multiple light source forming means has a variable focal length optical integrator group including a plurality of wavefront splitting optical integrators movable along an optical axis, and the first variable power optical system. Converts the divergent light beam formed through the light beam conversion optical system into a substantially parallel light beam and guides the light beam to an incident surface of the optical integrator group, and the adjustment system controls the illumination area formed on the irradiated surface. The focal length of the optical integrator group is changed in order to adjust only the size of the optical integrator group to a desired value, and the first variable power optical system is changed in order to adjust only the illumination numerical aperture to a desired value. It is preferable to change the focal length of the system.

In this case, the optical integrator group includes a first optical integrator having a positive refractive power movable along the optical axis and a second optical integrator having a negative refractive power movable along the optical axis. A second optical integrator, and a third optical integrator having a positive refractive power fixed along the optical axis, wherein the adjusting system adjusts the focal point of the optical integrator group without substantially moving a rear focal plane thereof. In order to continuously change the distance, it is preferable that the first optical integrator and the second optical integrator are independently moved along the optical axis.

Further, according to a preferred aspect of the first invention, the light beam conversion optical system has a plurality of diffractive optical elements configured to be detachable from an illumination optical path, and the plurality of diffractive optical elements are Preferably, substantially parallel light beams from the light source means are converted into divergent light beams having different cross-sectional shapes.

According to a second aspect of the present invention, there is provided the illumination optical device according to the first aspect of the present invention, and a projection optical system for projecting and exposing a mask pattern disposed on the surface to be irradiated onto a photosensitive substrate. An exposure apparatus is provided.
In this case, the adjustment system is configured to control the first variable power optical system and the second
It is preferable to adjust each focal length or each magnification of the variable power optical system.

Further, according to a third aspect of the present invention, a step of illuminating a mask disposed on the surface to be illuminated by the illumination optical device of the first aspect, and transferring the illuminated pattern of the mask onto a photosensitive substrate. And a method of manufacturing a microdevice. In this case, it is preferable to include a step of adjusting each focal length or each magnification of the first variable power optical system and the second variable power optical system based on information on the pattern of the mask.

In order to solve the second object,
According to a fourth aspect of the present invention, there is provided an illumination optical device which illuminates a mask pattern having a predetermined pattern with a light beam for exposure,
An exposure system having a projection system for projecting and exposing the pattern image of the mask onto a photosensitive substrate, comprising: The apparatus is a light beam converting unit that converts the light beam for exposure into a light beam having a desired light intensity distribution based on input information from the input unit,
A first variable magnification optical system that adjusts an illumination numerical aperture at the mask based on input information from the input unit, and a large illumination area formed on the mask based on input information from the input unit; And a second variable power optical system for changing the magnification. In this case, the illumination optical device includes an optical integrator that uniformly illuminates the mask, and the first variable power optical system is disposed on an incident side of the optical integrator.
It is preferable that the second variable power optical system is arranged on the exit side of the optical integrator.

Further, in the fifth invention of the present invention, an illuminating step of illuminating a mask pattern having a predetermined pattern with a light beam for exposure, and an exposing step of projecting and exposing a pattern image of the mask on a photosensitive substrate. In the method for manufacturing a micro device, the illumination step includes an input step of inputting information on an exposure condition on the photosensitive substrate or an illumination condition on the mask, and an exposure step based on input information from the input step. A light beam converting step of converting a light beam into a light beam having a desired light intensity distribution; an illumination area changing step of changing a size of an illumination area formed on the mask based on input information from the input step; Adjusting the illumination numerical aperture of the mask based on input information from the means. In this case, it is preferable that the adjusting step includes correcting the value of the illumination numerical aperture changed by the illumination area changing step to keep the value of the illumination numerical aperture substantially constant.

According to a sixth aspect of the present invention, there is provided an illumination optical apparatus for illuminating a mask pattern having a predetermined pattern with a light beam for exposure, and a projection system for projecting and exposing a pattern image of the mask on a photosensitive substrate. An exposure apparatus having
The illumination optical device changes a light intensity distribution at or near a pupil position of the illumination optical device, and adjusts an illumination numerical aperture of the mask according to a change in the light intensity distribution caused by the change device. An exposure apparatus having an adjusting unit is provided. In this case, it is preferable that the changing means includes a light beam converting means for selectively converting the light beam for exposure into one light beam among a plurality of light beams having different light intensity distributions. Further, in this case, the light beam converting means is provided with a first diffractive optical member forming a first light intensity distribution, and the first light intensity distribution is provided exchangeably with the first diffractive optical member with respect to an optical path. It is preferable to have a second diffractive optical member that forms a different second light intensity distribution.

Further, according to a seventh aspect of the present invention, an illumination step of illuminating a mask pattern having a predetermined pattern using an illumination optical device, and projecting a pattern image of the mask onto a photosensitive substrate using a projection system. In the method for manufacturing a micro device including an exposing step of exposing, the illuminating step includes a changing step of changing a light intensity distribution at or near a pupil position of the illumination optical device, and a change in the light intensity distribution due to the changing step. Adjusting the illumination numerical aperture of the mask according to the method.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a first variable power optical system for adjusting the illumination NA on an irradiated surface and a second variable optical system for changing the size of an illumination area formed on the irradiated surface are described. Optical system. In a typical embodiment of the present invention, a light beam conversion optical system for converting a light beam from the light source unit into a divergent light beam having a predetermined cross-sectional shape is provided.
The first variable power optical system condenses the divergent light beam and guides the divergent light beam to the entrance surface of the multiple light source forming means, and the second variable power optical system collects the light beams from the multiple light sources formed by the multiple light source forming means. To the surface to be irradiated.

Specifically, when a wavefront splitting optical integrator such as a micro fly's eye or a fly's eye lens is used as the multiple light source forming means, the first variable power optical system is formed via a light beam converting optical system. The divergent light beam is converted into a substantially parallel light beam and guided to the incident surface of the optical integrator. The second variable power optical system condenses the light beam from the secondary light source formed on the rear focal plane of the optical integrator and guides the light beam to the irradiated surface. In this case, the shape of each lens element (or microlens) constituting the micro fly's eye or fly's eye lens is similar to the shape of the illumination area formed on the surface to be illuminated, and the size is the second variable power optical. Depends on the focal length of the system.

Therefore, when the focal length of the second variable power optical system is changed, the size of the illumination area formed on the irradiated surface changes, and the illumination NA on the irradiated surface also changes. On the other hand, when the focal length of the first variable power optical system is changed, the size of the illuminated field formed on the entrance surface of the optical integrator changes. Changes. Thus,
By changing the focal length of the second variable power optical system,
The desired value can be adjusted by changing the size of the illumination area formed on the irradiation surface. Then, by changing the focal length of the first variable power optical system, it is possible to adjust the illumination NA changed with the change of the focal length of the second variable power optical system to a desired value.

As described above, in the illumination optical apparatus according to the present invention, the loss of light amount is favorably suppressed by adjusting each focal length (or each magnification) of the first variable power optical system and the second variable power optical system. In addition, the illumination NA and the size of the illumination area can be adjusted to desired values. Therefore, in the exposure apparatus incorporating the illumination optical device of the present invention, the size of the exposure area and the σ value can be adjusted to desired values while satisfactorily suppressing the light amount loss in the aperture stop and the illumination field stop. That is, in the exposure apparatus of the present invention, the size of the illumination area (exposure area) and the σ value are set to optimal values according to the characteristics of the microdevice to be manufactured or the characteristics of the mask to be used. Under high exposure illuminance and favorable exposure conditions, favorable projection exposure with high throughput can be performed.

In an exposure method for exposing a pattern of a mask disposed on a surface to be irradiated to a photosensitive substrate by using the illumination optical device of the present invention or a method for manufacturing a microdevice, the method may be performed under favorable exposure conditions. , It is possible to produce a good microdevice.

Further, according to the present invention, in order to change the exposure condition or the illumination condition, changing means or light beam converting means (for example, a diffractive optical member 3 for forming a circular light beam, a diffractive optical member 3a for forming an annular light beam, And a pupil position of the illumination optical system (a secondary light source position formed by an optical integrator or a position optically conjugate with the same) by a mechanism for setting one of the diffractive optical members 3b for forming a quadrupole beam in the illumination light path. Or, if the light intensity distribution near that position is changed,
Although the illumination numerical aperture changes, the change in the illumination numerical aperture can be corrected by adjusting (changing) the magnification or the focal length of the first variable power optical system as the adjusting means. Therefore, it is possible to realize an exposure apparatus and a microdevice manufacturing method capable of exposing a good mask pattern to a photosensitive substrate such as a wafer under a desired exposure condition or a desired illumination condition.

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a view schematically showing a configuration of an exposure apparatus provided with an illumination optical device according to the first embodiment of the present invention. In FIG. 1, the illumination optical device is set to perform ordinary circular illumination. The exposure apparatus shown in FIG. 1 includes, for example, 2 light sources 1 for supplying exposure light (illumination light).
An excimer laser light source for supplying light having a wavelength of 48 nm or 193 nm is provided. From light source 1 to reference optical axis AX
The substantially parallel light beam emitted along the light beam is shaped into a light beam having a desired rectangular cross section via a shaping optical system (not shown), and then enters the optical delay unit 2.

FIG. 2 is a perspective view illustrating the internal configuration and operation of the optical delay unit 2 of FIG. As shown in FIG. 2, the optical delay unit 2 includes a half mirror 200 inclined at 45 degrees with respect to the optical axis AX. Therefore, the light beam incident on the half mirror 200 along the optical axis AX is equal to the light beam transmitted through the half mirror 200 and + X
The light beam is split into light beams reflected in the direction. Half mirror 2
The light beam transmitted through 00 is incident on the diffractive optical element (DOE) 3 for circular illumination along the optical axis AX.

On the other hand, the light beam reflected in the + X direction by the half mirror 200 is reflected in the -Y direction by the first reflection mirror 201, reflected in the -X direction by the second reflection mirror 202, and is reflected by the third reflection mirror. After being reflected by the mirror 203 in the + Y direction and by the fourth reflecting mirror 204 in the + X direction, the light returns to the half mirror 200. The light flux returning to the half mirror 200 is split into a light flux transmitted through the half mirror 200 and a light flux reflected in the −Z direction by the half mirror 200. The light beam reflected in the −Z direction by the half mirror 200 enters the diffractive optical element 3 along the optical axis AX. On the other hand, the light beam transmitted through the half mirror 200 passes through the first reflection mirror 201 to the fourth reflection mirror 204,
Return to the half mirror 200 again.

As described above, the light beam incident on the optical delay unit 2 along the optical axis AX is split into a light beam transmitted through the half mirror 200 as a beam splitter and a light beam reflected by the half mirror 200. The light beam reflected by the half mirror 200 returns to the half mirror 200 after being sequentially deflected by four reflection mirrors 201 to 204 arranged so as to form a rectangular delay optical path. At this time, the incident position of the light beam incident on the half mirror 200 along the optical axis AX coincides with the re-incident position of the light beam returning to the half mirror 200 via the rectangular delay optical path. Four reflection mirrors 201 to 20
4 are arranged.

Therefore, the light beam P1 reflected in the -Z direction by the half mirror 200 after passing through the delay optical path once is emitted along the same optical axis AX as the light beam P0 transmitted through the half mirror 200 without passing through the delay optical path. Then, an optical path length difference equal to the optical path length of the delay optical path is provided between the light flux P0 and the light flux P1. Similarly, the light beam P2 reflected by the half mirror 200 after passing through the delay optical path twice is emitted along the same optical axis AX as the light beam P0 and the light beam P1. At this time, an optical path length difference equal to twice the optical path length of the delay optical path is provided between the light beams P0 and P2, and an optical path length difference equal to the optical path length of the delay optical path is provided between the light beams P1 and P2. Is given.
That is, the optical delay unit 2 converts the light beam incident along the optical axis AX into a plurality of light beams temporally (in theory, an infinite number of light beams, but practically if the influence of a light beam with small energy is ignored). Is divided into a finite number of light beams), and an optical path length difference equal to the optical path length of the delay optical path is provided between two temporally continuous light beams.

In general, the reflectance of the reflecting mirror is different between the incidence of P-polarized light and the incidence of S-polarized light.
Higher reflectance than polarized light incidence can be ensured. Therefore, it is preferable that the optical delay unit 2 is configured so that the light flux enters the four reflection mirrors 201 to 204 in the S-polarized state in order to avoid optical loss in the delay optical path. In the case of the present embodiment, as shown in FIG. 2, by causing a light beam to enter the half mirror 200 in the P-polarized state, S-polarized light can enter the four reflection mirrors 201 to 204.

As described above, the optical delay A 2 causes the optical axis A
The light beam incident along X is temporally divided into a plurality of light beams, and an optical path length difference equal to the optical path length of the delay optical path is provided between two temporally continuous light beams. Here, the given optical path length difference is set to be equal to or longer than the temporal coherence length of the light beam from the coherent light source 1. Therefore, coherency (coherence) can be reduced in the wave train divided by the optical delay unit 2, and the occurrence of interference fringes and speckles on the surface to be illuminated can be favorably suppressed. More detailed configuration and operation of this type of optical delay means are described in, for example, Japanese Patent Application Laid-Open No. 11-174365,
Japanese Patent Application No. 10-117434 specification and drawings, Japanese Patent Application No. 11-21591 specification and drawings, Japanese Patent Application No. 11-2
No. 5629 and the drawings.

As described above, the rectangular, substantially parallel light flux passing through the optical delay section 2 enters the diffractive optical element 3. Generally, a diffractive optical element is used to expose light (illumination light) to a glass substrate.
And has a function of diffracting the incident beam to a desired angle. Specifically, the diffractive optical element 3 for circular illumination is
A rectangular, substantially parallel light beam incident along the optical axis AX is
The light is converted into a divergent light beam having a circular cross section. Thus, the diffractive optical element 3 constitutes a light beam conversion optical system for converting the light beam from the light source 1 into a divergent light beam having a predetermined cross-sectional shape (in this case, a circular shape).

The circular divergent light beam passing through the diffractive optical element 3 passes through a zoom lens 4 serving as a first condenser optical system (first variable power optical system), and then serves as a multiple light source forming means or an optical integrator. The light enters the micro fly's eye 5. Thus, a circular illumination field is formed on the entrance surface of the micro fly's eye 5. The size of the formed illumination field (that is, its diameter or radius) changes depending on the focal length of the zoom lens 4 as described later. The micro fly's eye 5 is an optical element composed of a large number of rectangular microlenses (microlens elements) having a positive refracting power arranged vertically and horizontally and densely. Generally, a micro fly's eye is formed by, for example, performing an etching process on a parallel flat glass plate to form a group of minute lenses.

Here, each micro lens constituting the micro fly's eye is smaller than each lens element constituting the fly's eye lens. Also, unlike a fly-eye lens composed of lens elements isolated from each other, the micro fly's eye is formed integrally with a large number of micro lenses without being isolated from each other. However, the micro fly's eye is the same as the fly's eye lens in that the lens elements having positive refractive power are arranged vertically and horizontally. Note that FIG. 1 and other related FIGS.
In FIG. 7 and FIG. 7, the number of the micro lenses constituting the micro fly's eye is shown to be much smaller than the actual number for the sake of clarity.

Therefore, the light beam incident on the micro fly's eye 5 is two-dimensionally divided by a large number of microlenses, and one light source image is provided on the rear focal plane of each microlens (that is, near the exit surface). It is formed. Thus, on the rear focal plane of the micro fly's eye 5, a large number of light sources (hereinafter, referred to as "secondary light sources") having the same circular shape as the illumination field formed by the light beam incident on the micro fly's eye 5 are formed. As described above, the micro fly's eye 5 is a wavefront splitting type optical integrator, and the light source 1
A plurality of light sources forming means for forming a large number of light sources (a large number of light beams) based on the light beams from the light source.

The focal length of the zoom lens 4 is set so that the front focal plane coincides with the diffraction plane of the diffractive optical element 3 and the rear focal plane coincides with the entrance plane of the micro fly's eye 5. It is preferable to change the temperature. Therefore, it is preferable that the zoom lens 4 includes three lens groups that can move independently of each other along the optical axis. A light beam from a circular secondary light source formed on the rear focal plane of the micro fly's eye 5 enters an aperture stop 6 for circular illumination disposed near the light source. This aperture stop 6
The micro fly's eye 5 has a circular opening (light transmitting part) corresponding to a circular secondary light source formed on the rear focal plane of the micro fly's eye 5.

The diffractive optical element 3 is configured to be insertable into and removable from the illumination optical path, and is switchable between a diffractive optical element 3a for annular deformation illumination and a diffractive optical element 3b for quadrupole deformation illumination. Have been. The configuration and operation of the diffractive optical element 3a for annular deformation illumination and the diffractive optical element 3b for quadrupole deformation illumination will be described later. Also, the zoom lens 4
Is configured such that the focal length can be continuously changed within a predetermined range as described above. Further, the aperture stop 6 is configured so as to be freely inserted into and removed from the illumination optical path, and has a plurality of aperture stops for circular illumination having different sizes of openings, and a plurality of ring-shaped deformation illuminations having different sizes of openings. And a plurality of aperture stops for quadrupole deformation illumination having different aperture sizes.

Here, switching between the diffractive optical element 3 for circular illumination and the diffractive optical element 3a for annular deformation illumination or the diffractive optical element 3b for quadrupole deformation illumination is performed by a command from the control system 21. This is performed by the first drive system 22 that operates based on this. The change in the focal length of the zoom lens 4 is performed by the second drive system 23 that operates based on a command from the control system 21. Further, switching between the aperture stop 6 for circular illumination and another aperture stop is performed by a third drive system 24 that operates based on a command from the control system 21.

The switching between the aperture stop 6 for circular illumination and another aperture stop is performed by an appropriate method such as a turret method or a slide method.
Further, the aperture stop is not limited to the aperture stop of the turret type, the slide type, and the like, and may be fixedly mounted in the illumination optical path so that the size and shape of the light transmission area can be appropriately changed. Further, instead of a plurality of circular aperture stops, an iris stop capable of continuously changing the circular aperture diameter can be provided.

The light from the secondary light source through the aperture stop 6 having the circular aperture is subjected to the light condensing action of the zoom lens 7 as a second condenser optical system (second variable power optical system). Thereafter, a predetermined surface optically conjugate with a mask 10 described later is illuminated in a superimposed manner. In this way, a rectangular illumination field similar to the shape of each micro lens constituting the micro fly's eye 5 is formed on the predetermined surface. Then, the size of the rectangular illumination field formed on the predetermined surface and the illumination NA change depending on the focal length of the zoom lens 7 as described later.

The zoom lens 7 changes its focal length continuously so that its front focal plane coincides with the rear focal plane of the micro fly's eye 5 and its rear focal plane coincides with the above-mentioned predetermined plane. Preferably. Therefore, like the zoom lens 4, the zoom lens 7 preferably includes three lens groups that can move independently of each other along the optical axis. As described above, the zoom lens 7 is configured so that the focal length can be continuously changed within a predetermined range, and the change in the focal length is controlled by the fourth drive system that operates based on an instruction from the control system 21. 25.

A mask blind 8 as an illumination field stop is arranged on a predetermined surface optically conjugate with the mask 10. Opening of mask blind 8 (light transmitting part)
After receiving the light condensing action of the relay optical system 9, the light beam passing through the mask illuminates the mask 10 on which a predetermined pattern is formed in a superimposed manner. Thus, the relay optical system 9 forms an image of the rectangular opening of the mask blind 8 on the mask 10.

The light beam transmitted through the pattern of the mask 10 is
An image of a mask pattern is formed on a wafer (or plate) 12 which is a photosensitive substrate via a projection optical system 11. The wafer 12 is held on a wafer stage 13 that can move two-dimensionally in a plane orthogonal to the optical axis AX of the projection optical system 11. Thus, the wafer 12
Is performed by one-shot exposure or scan exposure (scanning exposure) while the two-dimensional drive control is performed, whereby the pattern of the mask 10 is sequentially exposed on each exposure area (shot area) of the wafer 12.

In the batch exposure method, a mask pattern is collectively exposed to each exposure area of a wafer according to a so-called step-and-repeat method. In this case, the shape of the illumination area on the mask 10 is a rectangular shape close to a square, and the cross-sectional shape of each micro lens of the micro fly's eye 5 is also a rectangular shape close to a square. On the other hand, in the scan exposure method, according to a so-called step-and-scan method, a mask pattern is scanned and exposed on each exposure region of the wafer while the mask and the wafer are relatively moved with respect to the projection optical system. In this case, the shape of the illumination area on the mask 10 is a rectangular shape having a ratio of the short side to the long side of, for example, 1: 3, and the cross-sectional shape of each micro lens of the micro fly's eye 5 is similar to this. Becomes

FIG. 3 is a diagram for explaining the relationship between the focal length of the zoom lens 4 and the zoom lens 7, the size of a rectangular illumination field formed on a predetermined surface conjugate with the mask 10, and the illumination NA. . In FIG. 3A, the diffractive optical element 3
The light beam 30 emitted from the intersection between the diffraction surface of the optical axis AX and the optical axis AX becomes parallel to the optical axis AX via the zoom lens 4 set to the maximum focal length f11, Incident. Micro fly eye 5
It is composed of a minute lens having a focal length of fm. Here, the size of each minute lens along the plane of FIG. 3 is d.

The outermost light ray 31 emitted from the micro fly's eye 5 in parallel with the optical axis AX has a maximum focal length f2.
After passing through the zoom lens 7 set to 1, the incident angle θ
At 21, the optical axis AX reaches the intersection point between the predetermined plane 32 conjugate with the mask 10 and the optical axis AX. Thus, a rectangular illumination field 33 similar to the shape of the micro lens is formed on the predetermined surface 32. And
The size of the illumination field 33 along the plane of FIG. 3 is φ1.

Here, as shown in FIG. 3B, the focal length of the zoom lens 4 is changed from the maximum focal length f11 to the minimum focal length f12, and the focal length of the zoom lens 7 is reduced from the maximum focal length f21 to the minimum. Focal length f22
To change. In this case, the light beam 30 emitted from the intersection of the diffraction surface of the diffractive optical element 3 and the optical axis AX at the maximum emission angle θ1 is parallel to the optical axis AX via the zoom lens 4 set to the minimum focal length f12. And enters the micro fly's eye 5.

The outermost light ray 31 emitted from the micro fly's eye 5 in parallel with the optical axis AX has a minimum focal length f2.
After passing through the zoom lens 7 set to 2, the incident angle θ
At 22, the point of intersection between the optical axis AX and the predetermined plane 32 conjugate with the mask 10 is reached. Thus, a rectangular illumination field 33 similar to the shape of the micro lens is formed on the predetermined surface 32. here,
The size of the illumination field 33 along the plane of FIG. 3 is φ2.

In FIG. 3A, the following equations (1) and (2) hold. f11 · sin θ1 = f21 · sin θ21 (1) φ1 = (f21 / fm) d (2) Further, in FIG. 3B, the relations expressed by the following equations (3) and (4) hold. f12 · sin θ1 = f22 · sin θ22 (3) φ2 = (f22 / fm) d (4)

Referring to the above equations (2) and (4), the illumination field 33 is a projection of a minute lens by the zoom lens 7, and the size φ of the illumination field 33 is proportional to the focal length f2 of the zoom lens 7. You can see that. That is, FIG.
It can be seen that the size φ1 of the illumination field 33 in FIG. 3A is the maximum size, and the size φ2 of the illumination field 33 in FIG. 3B is the minimum size.

Referring to the above equations (1) and (3), since θ1 is a value unique to the diffractive optical element 3,
The sine value sin θ2 of the incident angle θ2 to the predetermined surface 32 is the focal length f1 of the zoom lens 4 and the focal length f of the zoom lens 7.
It can be seen that it depends on the ratio to 2, that is, f1 / f2. In other words, the illumination N of the illumination field 33 in FIG.
It can be seen that A is proportional to f11 / f21, and the illumination NA of the illumination field 33 in FIG. 3B is proportional to f12 / f22.

As can be seen with reference to FIGS. 3A and 3B, the size of the circular illumination field formed on the entrance surface of the micro fly's eye 5 is
Is proportional to the focal length f1. That is, the size of the illumination field formed on the entrance surface of the micro fly's eye 5 in FIG. 3A is the largest, and the size of the illumination field formed on the entrance surface of the micro fly's eye 5 in FIG. It turns out that it is the minimum.

As described above, when the focal length f2 of the zoom lens 7 is changed, the size of the illumination field formed on the predetermined surface 32, the size of the illumination area formed on the pattern surface of the mask 10, and furthermore, The size of the exposure area formed on the exposure surface of the wafer 12 changes. Also, the zoom lens 7
As the focal length f2 changes, the illumination NA on the predetermined surface 32 and, consequently, the illumination NA on the pattern surface of the mask 10 change. More specifically, when the focal length f2 of the zoom lens 7 is increased, the illumination area on the mask 10 increases, and the illumination NA increases. As described above, the zoom lens 7 constitutes a second variable power optical system for changing the size of the illumination area formed on the mask 10 (and, consequently, the wafer 12) which is the surface to be irradiated.

On the other hand, when the focal length f1 of the zoom lens 4 is changed, the size of the illumination area formed on the pattern surface of the mask 10 does not change, and And the illumination NA on the mask 10 changes. More specifically,
When the focal length f1 of the zoom lens 4 is reduced, only the illumination NA on the mask 10 is reduced without changing the size of the illumination area on the mask 10. Thus, the zoom lens 4 constitutes a first variable power optical system for changing only the illumination NA on the mask 10 which is the surface to be irradiated.

Accordingly, in the present embodiment, by setting the focal length of the zoom lens 7 to a predetermined value, the illumination area of a desired size on the mask 10 is substantially prevented from being lost by the mask blind 8. Can be obtained. Further, by setting the focal length of the zoom lens 4 to a predetermined value with respect to the focal length of the zoom lens 7 set to a predetermined value, substantially no light loss occurs at the aperture stop 6 and the At the desired size of illumination N
A can be obtained.

As described above, the diffractive optical element 3 is configured so as to be freely inserted into and removed from the illumination optical path, and has a diffractive optical element 3a for annular deformation illumination and a diffractive optical element 3 for quadrupole deformation illumination.
It is configured to be switchable with b. Hereinafter, the annular deformation illumination obtained by setting the diffractive optical element 3a in the illumination optical path instead of the diffractive optical element 3 will be described.

FIG. 4 shows a diffractive optical element 3 for annular deformation illumination.
It is a figure explaining operation of a. As shown in FIG. 4, the diffractive optical element 3a for annular deformation illumination converts a circular beam having a circular light beam cross section perpendicularly incident along the optical axis AX into an optical axis A.
The light is converted into a ring-shaped beam having a ring-shaped light beam cross section by diffracting the light at equal angles around X in all directions. Accordingly, when a parallel light beam having a circular cross section is incident on the diffractive optical element 3a along the optical axis AX, as shown in FIG. As described above, the diffractive optical element 3a forms a light beam conversion optical system for converting the light beam from the light source 1 into a substantially annular divergent light beam.

The divergent luminous flux in the form of an orb through the diffractive optical element 3a enters the micro fly's eye 5 after passing through the zoom lens 4. Thus, an annular illumination field is formed on the entrance surface of the micro fly's eye 5. As a result, a secondary light source having the same annular shape as the illumination field formed on the incident surface is formed on the rear focal plane of the micro fly's eye 5. As described above, an annular secondary light source is formed on the rear focal plane of the micro fly's eye 5 based on the light flux from the light source 1 with almost no loss of light amount.

The diffractive optical elements 3 to 3
Switching from the circular aperture stop to the annular aperture stop is performed in response to the switch to a. Here, the annular aperture stop positioned in the illumination optical path is an aperture stop having an annular opening corresponding to the annular secondary light source. As described above, by using the diffractive optical element 3a for annular deformation illumination, it is possible to form an annular secondary light source with little loss of light amount based on the light flux from the light source 1, and as a result, The annular deformation illumination can be performed while satisfactorily suppressing the light amount loss in the aperture stop that restricts the light flux from the light source.

Next, a quadrupole deformation illumination obtained by setting the diffractive optical element 3b in place of the diffractive optical element 3 in the illumination light path will be described. FIG. 5 is a diagram illustrating the operation of the diffractive optical element 3b for quadrupole deformation illumination. As shown in FIG. 5, the diffractive optical element 3b for quadrupole deformation illumination converts a circular beam having a circular light beam cross-section perpendicularly incident along the optical axis AX into four specific beams at equal angles around the optical axis AX. It is converted into four narrow beams by diffracting along the direction. Therefore, this diffractive optical element 3
When a parallel light beam having a circular cross section is incident on b along the optical axis AX, it becomes a quadrupolar divergent light beam as shown in FIG. As described above, the diffractive optical element 3b converts the light flux from the light source 1 into the optical axis A.
A light beam conversion optical system for converting into four divergent light beams decentered with respect to X is configured.

The quadrupolar divergent light beam passing through the diffractive optical element 3 b passes through the zoom lens 4 and then enters the micro fly's eye 5. Thus, a quadrupole illumination field is formed on the incidence surface of the micro fly's eye 5. As a result, a quadrupolar secondary light source is formed on the rear focal plane of the micro fly's eye 5 in the same manner as the illumination field formed on the incident plane. As described above, the rear focal plane of the micro fly's eye 5 has almost no light quantity loss based on the light flux
A polar secondary light source is formed.

The diffractive optical elements 3 to 3
Switching from the circular aperture stop to the quadrupole aperture stop is performed in response to the switch to b. Here, the four-pole aperture stop positioned in the illumination light path is an aperture stop having a fourth opening corresponding to the quadrupole secondary light source. As described above, by using the diffractive optical element 3b for quadrupole deformation illumination, it is possible to form a quadrupolar secondary light source with little loss of light amount based on the light beam from the light source 1, and as a result, Quadrupole deformation illumination can be performed while satisfactorily suppressing the light amount loss in the aperture stop that restricts the light flux from the secondary light source.

Hereinafter, the operation of adjusting the size of the illumination area and the illumination NA in the present embodiment will be specifically described. First, information on various masks to be sequentially exposed according to the step-and-repeat method or the step-and-scan method, information on illumination conditions of various masks or exposure conditions on a wafer to be sequentially exposed, etc. It is input to the control system 21 via the input means 20. The control system 21 controls a desired size of an illumination area (exposure area) for various masks and wafers,
Information such as an optimum illumination NA, an optimum line width (resolution), and a desired depth of focus is stored in an internal memory unit, and the first driving system 22 to the fourth driving system respond to an input from the input unit 20. Provide appropriate control signals to system 25.

That is, when circular illumination is normally performed under an illumination area of a desired size, an optimal illumination NA, an optimal resolution and a desired depth of focus, the first drive system 22 controls the control system 21.
The diffractive optical element 3 for circular illumination is positioned in the illumination optical path on the basis of the instruction from. Then, in order to obtain an illumination area having a desired size on the mask 10, the fourth drive system 25 sets the focal length of the zoom lens 7 based on a command from the control system 21. Further, in order to obtain a desired illumination NA on the mask 10, the second drive system 23 sets the focal length of the zoom lens 4 based on a command from the control system 21. Further, in order to limit the circular secondary light source formed on the rear focal plane of the micro fly's eye 5 in a state where the light amount loss is suppressed well, the third drive system 24 is controlled by the control system 2.
The desired circular aperture stop is positioned in the illumination optical path on the basis of the instruction from 1.

Further, if necessary, the focal length of the zoom lens 4 is changed by the second drive system 23 or the focal length of the zoom lens 7 is changed by the fourth drive system 25 to form the mask 10 on the mask 10. The size of the illumination area and the illumination NA can be appropriately changed independently of each other. In this case, a desired circular aperture stop is selected and positioned in the illumination optical path according to a change in the size of the circular secondary light source accompanying a change in the focal length of the zoom lens 4.

As described above, the input means 20, the control system 2
The first, second and third drive systems 23 and 24
An adjusting system for adjusting the focal lengths of the first variable power optical system and the second variable power optical system in order to set A and the size of the illumination area to desired values is configured. Thus,
It is possible to perform optimal circular illumination by setting the size of the illumination area formed on the mask 10 and the illumination NA to desired values with almost no loss of light quantity.

Further, in the case of performing annular deformation illumination under an illumination area of a desired size, an optimal illumination NA, an optimal resolution, and a desired depth of focus, the first drive system 22 responds to a command from the control system 21. Based on this, the diffractive optical element 3a for annular deformation illumination is positioned in the illumination optical path. Then, in order to obtain an illumination area having a desired size on the mask 10, the fourth drive system 25 sets the focal length of the zoom lens 7 based on a command from the control system 21. Further, in order to obtain a desired illumination NA on the mask 10, the second drive system 23 sets the focal length of the zoom lens 4 based on a command from the control system 21. Further, in order to limit the annular secondary light source formed on the rear focal plane of the micro fly's eye 5 in a state in which the light amount loss is properly suppressed, the third drive system 24 is controlled by the control system 2.
A desired annular aperture stop is positioned in the illumination optical path on the basis of the instruction from (1).

Further, if necessary, the focal length of the zoom lens 4 can be changed by the second drive system 23 or the focal length of the zoom lens 7 can be changed by the fourth drive system 25 to form on the mask 10. The size of the illumination area and the illumination NA can be appropriately changed independently of each other. In this case, according to a change in the size of the annular secondary light source (that is, the size of a circle circumscribing the annular secondary light source) due to a change in the focal length of the zoom lens 4, a desired annular aperture stop is provided. Is selected and positioned in the illumination light path.
In this way, the mask 10 is hardly lost.
By setting the size of the illumination area formed above and the illumination NA to desired values, optimal ring-shaped deformation illumination can be performed.

Further, in the case of performing quadrupole illumination under a desired illumination area, an optimum illumination NA, an optimum resolution and a desired depth of focus, the first drive system 22 responds to a command from the control system 21. Based on this, the diffractive optical element 3b for annular deformation illumination is positioned in the illumination optical path. In order to obtain an illumination area having a desired size on the mask 10, the fourth
The drive system 25 sets the focal length of the zoom lens 7 based on a command from the control system 21. Further, in order to obtain a desired illumination NA on the mask 10, the second drive system 23 sets the focal length of the zoom lens 4 based on a command from the control system 101. Further, in order to limit the quadrupole secondary light source formed on the rear focal plane of the micro fly's eye 5 in a state where the light quantity loss is suppressed well, the third drive system 24 responds to a command from the control system 21. Based on this, the desired 4-pole aperture stop is positioned in the illumination optical path.

Further, if necessary, the focal length of the zoom lens 4 can be changed by the second drive system 23 or the focal length of the zoom lens 7 can be changed by the fourth drive system 25 to form on the mask 10. The size of the illumination area and the illumination NA can be appropriately changed independently of each other. In this case, according to a change in the size of the quadrupole secondary light source (that is, the size of a circle circumscribing the quadrupole secondary light source) due to a change in the focal length of the zoom lens 4, a desired four-pole secondary light source is changed.
A polar aperture stop is selected and positioned in the illumination light path.
In this way, the mask 10 is hardly lost.
Optimal quadrupole deformation illumination can be performed by setting the size of the illumination area formed above and the illumination NA to desired values, respectively.

As described above, in the present embodiment, by controlling the focal lengths of the zoom lens 4 as the first variable power optical system and the zoom lens 7 as the second variable power optical system,
The illumination NA on the mask 10 and the size of the illumination area, and thus the size of the exposure area and the σ value on the wafer 12, are adjusted to desired values while satisfactorily suppressing the light amount loss in the aperture stop 6 and the illumination field stop 8. can do. That is, in the exposure apparatus of the present embodiment, the mask 1 to be used depends on the characteristics of the microdevice to be manufactured.
According to the characteristic of 0, the size of the illumination area (exposure area) and the σ value are respectively set to optimal values, and good projection exposure with high throughput is performed under high exposure illuminance and good exposure conditions. be able to.

In the above-described embodiment, deformed illumination such as ring-shaped deformed illumination or quadrupole deformed illumination and normal circular illumination are performed while satisfactorily suppressing the light amount loss in the aperture stop for restricting the secondary light source. be able to. Therefore, the resolution and the depth of focus of the projection optical system suitable for the fine pattern to be exposed and projected can be obtained by appropriately changing the type of the deformed illumination. As a result, good projection exposure with high throughput can be performed under high exposure illuminance and good exposure conditions.

Further, in order to change the exposure condition or the illumination condition, changing means or light beam converting means (for example, a diffractive optical member 3 for forming a circular light beam, a diffractive optical member 3a for forming an annular light beam, and a quadrupole light beam) One of the diffractive optical members 3b for forming
When the light intensity distribution at the pupil position of the illumination optical system (the position of the secondary light source formed by the optical integrator or a position optically conjugate thereto) or the vicinity thereof is changed by a mechanism that sets one in the illumination light path, Illumination numerical aperture N
A may change. The change in the numerical aperture of the illumination caused by the change of the exposure condition or the illumination condition is determined by the first adjustment means.
The correction can be made by adjusting (changing) the magnification or the focal length of the variable power optical system 4.

In this case, the control system 21 sends an appropriate control signal to the first drive system 22 based on the exposure condition or the illumination condition of each mask or each wafer stored in the internal memory unit via the input means 20. , And output to the second drive system 23 and the third drive system 24, respectively. That is, the first drive system 22 sets an appropriate diffractive optical element (3, 3a, 3b) in the illumination light path, and the third drive system 24 sets an aperture stop having an appropriate shape or size. Is set in the illumination optical path, and at the same time, the first variable magnification optical system is adjusted (changed) to an appropriate magnification or an appropriate focal length by the second drive system 23 in order to correct a change in the illumination numerical aperture. . This makes it possible to realize an exposure apparatus and a microdevice manufacturing method capable of exposing a good mask pattern to a photosensitive substrate such as a wafer under a desired exposure condition or a desired illumination condition.

FIG. 6 is a diagram schematically showing a configuration of an exposure apparatus provided with an illumination optical device according to the second embodiment of the present invention. The second embodiment has a configuration similar to that of the first embodiment. However, in the first embodiment, an optical integrator having a single focal length and comprising a single micro fly's eye 5 is used as the multiple light source forming means, and the zoom lens 7 having a variable focal length is used as the condenser optical system. In the embodiment, the multiple light source forming means is 3
A condenser lens 7 having a variable focal length micro fly's eye group 50 composed of two micro fly's eyes 51 to 53 and having a constant focal length as a condenser optical system.
The only difference is that 0 is used.

Therefore, in FIG. 6, elements having the same functions as those of the first embodiment are denoted by the same reference numerals as in FIG. Hereinafter, the second embodiment will be described focusing on the differences from the first embodiment. In FIG. 6, the illumination optical device is set to perform ordinary circular illumination. However, as in the first embodiment, by changing the diffractive optical element, annular deformation illumination and quadrupole deformation illumination are possible. There is no duplicate description for this point.

In the second embodiment, in order from the light source side, a first micro fly's eye 51 composed of a minute lens having a positive refractive power is used.
And a second micro fly's eye 52 composed of a micro lens having a negative refractive power and a third micro fly eye 53 composed of a micro lens having a positive refractive power are provided. Here, each of the micro lenses constituting the micro fly's eyes 51 to 53 has a rectangular cross section and the same size.

The first micro fly's eye 51 and the second micro fly's eye 52 can move independently of each other along the optical axis AX.
Is fixed along the optical axis AX. Then, the first micro fly eye 51 and the second micro fly eye 52 are moved so that the rear focal plane of the micro fly eye group 50 does not move.
Are moved independently along the optical axis AX so that the focal length of the micro fly's eye group 50 changes continuously from the maximum focal length f501 to the minimum focal length f502. The change in the focal length of the micro fly's eye group 50 is performed by a drive system that operates based on a command from a control system, as in the first embodiment.

FIG. 7 is a diagram for explaining the relationship between the focal length of the zoom lens 4 and the micro fly's eye group 50, the size of a rectangular illumination field formed on a predetermined surface conjugate with the mask 10, and the illumination NA. It is. In FIG. 7A, a light ray 30 emitted from the intersection of the diffractive surface of the diffractive optical element 3 and the optical axis AX at the maximum emission angle θ1 passes through the zoom lens 4 set to the maximum focal length f11, and the optical axis is changed. It becomes parallel to AX and enters the micro fly's eye group 50. The micro fly's eye group 50 is set to the maximum focal length f501. Here, in each of the micro fly's eyes 51 to 53 constituting the micro fly's eye group 50, the size of each micro lens along the paper surface of FIG. 7 is d.

The outermost light ray 31 emitted from the micro fly's eye group 50 in parallel with the optical axis AX is the focal length f7.
After passing through the condenser lens 70 having 0, the light reaches the intersection of the optical axis AX and the predetermined plane 32 conjugate with the mask 10 at the incident angle θ21. Thus, a rectangular illumination field 33 similar to the shape of the micro lens is formed on the predetermined surface 32. Then, the size of the illumination field 33 along the plane of FIG. 7 is φ3.

As shown in FIG. 7B, the focal length of the zoom lens 4 is changed from the maximum focal length f11 to the minimum focal length f12, and the focal length of the micro fly's eye group 50 is changed to the maximum focal length f501. To the minimum focal length f502. In this case, the maximum emission angle θ1 from the intersection of the diffraction surface of the diffractive optical element 3 and the optical axis AX.
The light beam 30 emitted through the zoom lens 4 set in the minimum focal length f12 becomes parallel to the optical axis AX and enters the micro fly's eye group 50 set in the minimum focal length f502.

The outermost light ray 31 emitted from the micro fly's eye group 50 in parallel with the optical axis AX has a focal length f7
After passing through the condenser lens 70 having 0, the light reaches the intersection of the optical axis AX and the predetermined surface 32 conjugate with the mask 10 at the incident angle θ22. Thus, a rectangular illumination field 33 similar to the shape of the micro lens is formed on the predetermined surface 32. Here, the size of the illumination field 33 along the paper surface of FIG. 7 is φ4.

In FIG. 7A, the following equations (5) and (6) hold. f11 · sin θ1 = f70 · sin θ21 (5) φ3 = (f70 / f501) d (6) Further, in FIG. f12 · sin θ1 = f70 · sin θ22 (7) φ4 = (f70 / f502) d (8)

Referring to the above equations (6) and (8), it can be seen that the size φ of the illumination field 33 is inversely proportional to the focal length f50 of the micro fly's eye group 50. That is,
It can be seen that the size φ3 of the illumination field 33 in FIG. 7A is the minimum size, and the size φ4 of the illumination field 33 in FIG. 7B is the maximum size. Referring to the above equations (5) and (7), since the value of θ1 and the value of f70 are constant, the sine value si of the incident angle θ2 to the predetermined surface 32 is obtained.
It can be seen that nθ2 depends on the focal length f1 of the zoom lens 4. In other words, the illumination NA of the illumination field 33 in FIG. 7A is maximum in proportion to f11, and the illumination NA of the illumination field 33 in FIG. 7B is minimum in proportion to f12.

As described above, the micro fly's eye group 50
Is changed, the size of the illumination field formed on the predetermined surface 32 and, consequently, the size of the illumination area formed on the pattern surface of the mask 10 is changed. More specifically, when the focal length f50 of the micro fly's eye group 50 is increased, only the size of the illumination area on the mask 10 is reduced without changing the illumination NA on the mask 10. As described above, the micro fly's eye group 50 constitutes the multiple light source forming means, and the second changing means for changing the size of the illumination area formed on the mask 10 (and, consequently, the wafer 12) which is the surface to be irradiated. It constitutes a part of the magnification optical system.

On the other hand, when the focal length f1 of the zoom lens 4 is changed, the size of the illumination field formed on the incident surface of the micro fly's eye group 50 changes, and the illumination NA on the mask 10 changes. More specifically, when the focal length f1 of the zoom lens 4 is reduced, only the illumination NA on the mask 10 is reduced without changing the size of the illumination area formed on the mask 10. Thus, the zoom lens 4 constitutes a first variable power optical system for changing only the illumination NA on the mask 10 which is the surface to be irradiated.

Therefore, in the second embodiment, by setting the focal length of the micro fly's eye group 50 to a predetermined value, the desired size on the mask 10 can be obtained without substantially light loss at the mask blind 8. Illumination area can be obtained. Further, by setting the focal length of the zoom lens 4 to a predetermined value, it is possible to obtain an illumination NA of a desired size on the mask 10 without substantial light loss at the aperture stop 6.

FIG. 8 is a diagram schematically showing a configuration of an exposure apparatus provided with an illumination optical device according to the third embodiment of the present invention. The third embodiment has a configuration similar to that of the first embodiment. However, in the first embodiment, the micro fly's eye 5 which is an optical integrator of the wavefront division type is used as the multiple light source forming means, but in the third embodiment, the rod type integrator 500 which is the optical integrator of the internal reflection type is used. The only difference is that

Therefore, in FIG. 8, elements having the same functions as those of the first embodiment are denoted by the same reference numerals as in FIG. Hereinafter, the third embodiment will be described focusing on the differences from the first embodiment. In FIG. 8, the illumination optical device is set to perform normal circular illumination. However, as in the first embodiment, by changing the diffractive optical element, annular deformation illumination or quadrupole deformation illumination is possible. There is no duplicate description for this point.

In the third embodiment, the micro fly eye 5
In response to using the rod integrator 500 in place of the above, the diffractive optical element 3 and the rod integrator 5
A first imaging optical system (first variable power optical system) in the optical path between 00
And a zoom lens 71 serving as a second imaging optical system (second variable power optical system) instead of the zoom lens 7 and the relay optical system 9. Further, a mask blind 8 as an illumination field stop is arranged near the exit surface of the rod-type integrator 500.

Here, the zoom lens 41 is configured to continuously change the imaging magnification m1 while maintaining the diffraction surface of the diffractive optical element 3 and the incident surface of the rod-type integrator 500 optically conjugate. Have been. Further, the zoom lens 71 is configured to continuously change the imaging magnification m2 while maintaining the exit surface of the rod-type integrator 500 and the pattern surface of the mask 10 optically conjugate. The change in the magnification of the zoom lens 41 and the zoom lens 71 is performed by a drive system that operates based on a command from the control system, as in the first embodiment.

The rod-type integrator 500 is an internal reflection type glass rod made of a glass material such as quartz glass or fluorite, and uses a boundary surface between the inside and the outside, that is, a condensing point using total reflection on the inside surface. And a number of light source images corresponding to the number of internal reflections are formed along a plane parallel to the rod incident surface.
Here, most of the light source images formed are virtual images,
Only the light source image at the center (focus point) is a real image. That is,
The light beam incident on the rod-type integrator 500 is split in the angular direction by internal reflection, and a secondary light source composed of a large number of light source images is formed along a plane parallel to the incident surface through the light converging point.

The light from the secondary light source formed on the incident side by the rod-type integrator 500 is superimposed on the exit surface, and then uniformly illuminates the mask 10 on which a predetermined pattern is formed via the zoom lens 71. I do. As described above, the zoom lens 71 includes the emission surface of the rod-type integrator 500 and the mask 10 (and thus the wafer 1
2) is optically connected almost conjugately. Therefore,
On the mask 10, a rectangular illumination field similar to the cross-sectional shape of the rod-type integrator 500 is formed.

FIG. 9 is a diagram for explaining the relationship between the magnification of the zoom lens 41 and the zoom lens 71, the size of a rectangular illumination field formed on a predetermined surface conjugate with the mask 10, and the illumination NA. In FIG. 9A, the diffractive optical element 3
The light ray 30 emitted from the intersection of the diffraction surface and the optical axis AX at the maximum emission angle θ1 passes through the zoom lens 41 set to the maximum magnification m11, and then passes through the optical axis AX and the incident surface of the rod-type integrator 500. At an incident angle θ11. Here, the size of the exit surface of the rod-type integrator 500 along the paper surface of FIG. 9 is d5.

Optical axis AX and rod type integrator 500
The light beam 31 emitted at the emission angle θ11 from the intersection with the exit surface of the zoom lens 71 set to the maximum magnification m21
After that, the light reaches the intersection of the optical axis AX and the predetermined plane 32 conjugate with the mask 10 at the incident angle θ21. In this manner, a rectangular illumination field 33 similar to the emission surface of the rod-type integrator 500 (more precisely, similar to the shape of the opening of the mask blind 8) is formed on the predetermined surface 32. And
The size of the illumination field 33 along the plane of FIG. 9 is φ5.

Here, as shown in FIG. 9B, the magnification of the zoom lens 41 is changed from the maximum magnification m11 to the minimum magnification m12.
And the magnification of the zoom lens 71 is changed from the maximum magnification m21 to the minimum magnification m22. In this case, the light beam 30 emitted from the intersection of the diffraction surface of the diffractive optical element 3 and the optical axis AX at the maximum emission angle θ1 has the minimum magnification m.
After passing through the zoom lens 41 set to 12, the optical axis A
The incident light enters the intersection of X and the incident surface of the rod-type integrator 500 at an incident angle θ12.

Optical axis AX and rod type integrator 500
The light beam 31 emitted from the intersection with the emission surface at the emission angle θ12 is the zoom lens 71 set to the minimum magnification m22.
Through the optical axis AX at the incident angle θ22. Thus, a rectangular illumination field 33 similar to the emission surface of the rod-type integrator 500 is formed on the predetermined surface 32. Here, the size of the illumination field 33 along the plane of FIG. 9 is φ6.

In FIG. 9A, the following equations (9) and (10) hold. θ11 = m11 · θ1 = m21 · θ2 (9) φ5 = m21 · d5 (10) In FIG. 9B, the following equations (11) and (1)
The relationship shown in 2) holds. θ12 = m12 · θ1 = m22 · θ2 (11) φ6 = m22 · d5 (12)

Referring to the above equations (10) and (12), the size φ of the illumination field 33 is determined by the magnification m of the zoom lens 71.
It can be seen that it is proportional to 2. That is, the size φ5 of the illumination field 33 in FIG.
It can be seen that the size φ6 of the illumination field 33 in (b) is the minimum size.

Referring to the above equations (9) and (11), since the value of θ1 is invariable, the angle of incidence θ2 on the predetermined surface 32 depends on the magnification m1 of the zoom lens 4 and the magnification m2 of the zoom lens 71. , That is, m1 / m2. In other words, Teruno 3 in FIG.
It can be seen that the illumination NA of No. 3 depends on m11 / m21, and the illumination NA of illumination field 33 in FIG. 9B depends on m21 / m22.

As described above, the magnification m of the zoom lens 71
When 2 is changed, the size of the illumination area formed on the pattern surface of the mask 10 and the illumination NA change. More specifically, when the magnification m2 of the zoom lens 71 is increased, the illumination area on the mask 10 increases, and the illumination NA decreases. As described above, the zoom lens 71 constitutes a second variable power optical system for changing the size of the illumination area formed on the mask 10 which is the irradiated surface.

On the other hand, when the magnification m1 of the zoom lens 41 is changed, the size of the illumination field formed on the entrance surface of the micro fly's eye 5 is changed, and the illumination NA on the mask 10 is changed.
Changes. More specifically, when the magnification m1 of the zoom lens 41 is increased, the size of the illumination area formed on the pattern surface of the mask 10 does not change, and
Only the illumination NA above is increased. Thus, the zoom lens 41 constitutes a first variable power optical system for changing only the illumination NA on the mask 10 which is the surface to be irradiated.

Therefore, in the present embodiment, by setting the magnification of the zoom lens 71 to a predetermined value, the mask blind 8 does not substantially lose light and the mask 1
On 0, an illumination area of a desired size can be obtained. Further, by setting the magnification of the zoom lens 41 to a predetermined value with respect to the magnification of the zoom lens 7 set to a predetermined value, it is possible to obtain an illumination NA of a desired size on the mask 10.

In the third embodiment shown in FIG. 8, similarly to the first embodiment shown in FIG. 1, in order to change the exposure condition or the illumination condition, changing means or light beam converting means (for example, A mechanism for setting one of the diffractive optical member 3 for forming a circular light beam, the diffractive optical member 3a for forming an orbicular light beam, and the diffractive optical member 3b for forming a quadrupole light beam in an illumination light path)
When the light intensity distribution at the pupil position of the illumination optical system (the position of the secondary light source formed by the optical integrator or a position optically conjugate with it) or the vicinity thereof is changed, the illumination numerical aperture NA may change. . The change of the numerical aperture of the illumination accompanying the change of the exposure condition or the illumination condition,
The correction can be made by adjusting (changing) the magnification or the focal length of the first variable power optical system 41 as the adjusting means.

As described above, in the embodiment shown in FIGS. 1 and 8, the change in the value of the illumination numerical aperture caused by the change in the illumination visual field by the second variable power optical system (7, 71) is determined by the first variable. Adjustment (change) of the magnification or focal length of the magnification optical system (4, 41)
, The illumination numerical value can be kept substantially constant. Therefore, even under such specific conditions, the projection exposure can be performed with high illumination efficiency.

By the way, changing means or light beam converting means (for example, one of the diffractive optical member 3 for forming a circular light beam, the diffractive optical member 3a for forming an orbicular light beam, and the diffractive optical member 3b for forming a quadrupolar light beam is used. The illuminance distribution on the mask or the wafer may change due to the mechanism for setting the illumination optical path, and the illuminance may become non-uniform. In that case, a method of moving some optical elements (such as lenses) of the second condenser optical system (magnification optical systems 7, 70) or the relay optical system (imaging optical system 9), or an optical integrator (5, 50) ,
By using a method in which a plurality of filters having predetermined angular characteristics for adjusting the illuminance distribution are exchangeably provided in the optical path between the mask 500 and the mask 10, the illuminance distribution on the mask or the wafer can be made uniform. . However, since the illumination numerical aperture may change in accordance with the illuminance correction, the change in the illumination numerical aperture caused by the correction of the illuminance distribution by the illuminance correction means is performed by a first variable power optical system (a first condenser optical system). 4. It can be corrected by adjusting (changing) the magnification or the focal length of the first imaging optical system 41).

The light beam converting means (changing means) described in each of the above embodiments converts one desired light intensity distribution among a plurality of light beams having different light intensity distributions from each other based on the light beam for exposure. The function of selectively converting the light beam having the light beam, that is, the light beam for exposure into a light beam having a predetermined first light intensity distribution and a predetermined second light intensity distribution different from the first light intensity distribution. Since it has a function to convert it into a light beam having one of the following light beams, the pupil position of the illumination optical system (the position of the secondary light source formed by the optical integrator or a position optically conjugate with it) or in the vicinity of the position Can be changed to a desired light intensity distribution. Light flux converting means (changing means) for changing the light intensity distribution at or near the pupil position of the illumination optical system.
Are diffractive optical elements (3, 3) that form a desired divergent light beam
a, 3b), the convex conical refraction surface prism (or a prism having a concave conical refraction surface) capable of forming an annular light beam, and a convex shape capable of forming a quadrupolar light beam. The configuration may be such that the above-described four-sided pyramid-shaped refraction surface prism (or a prism having a concave four-sided pyramid-shaped refraction surface) can be exchanged.

As described above, the light beam converting means (changing means)
By selectively arranging one of the optical members having a diffractive action or a refraction action in the illumination light path, it is possible to convert the divergent light into a desired state. Furthermore, if a configuration is used in which three diffractive optical elements with interchangeable light flux converting means (changing means) and a variable power optical system are combined, an annular luminous flux formed at or near the pupil position of the illumination optical system is provided. The annular ratio (the ratio of the inner diameter of the annular zone to the outer diameter of the annular zone), the size of the circular luminous flux, and the distance from the center of the quadrupolar luminous flux can be continuously varied. Similarly, the light beam converting means (changing means) may have a configuration in which the above exchangeable prism (refractive optical element) and a variable power optical system are combined.

The present invention is realized by electrically, mechanically or optically connecting the optical members and the stages in the examples shown in FIGS. 1 to 9 so as to achieve the above-described functions. The exposure apparatus according to the above can be assembled. Next, a method for obtaining a semiconductor device as a micro device by forming a predetermined circuit pattern on a wafer or the like as a photosensitive substrate using the exposure apparatus in each example shown in FIGS. Figure 1 per example
This will be described with reference to the flowchart of FIG.

First, in step 301 of FIG.
A metal film is deposited on one lot of wafers. In the next step 302, a photoresist is applied on the metal film on the l lot of wafers. Then, step 30
3, using any one of the projection exposure apparatuses shown in FIGS. 1 to 9, an image of the pattern on the mask Exposure is transferred to each shot area sequentially.
Thereafter, in step 304, after the photoresist on the wafer of the lot is developed, step 3
At 05, a circuit pattern corresponding to the pattern on the mask is formed in each shot area on each wafer by etching using the resist pattern as a mask on that one lot of wafers. Thereafter, a device such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer and the like. According to the above-described semiconductor device manufacturing method, a semiconductor device having an extremely fine circuit pattern can be obtained with good throughput.

In the exposure apparatus shown in FIGS. 1 to 9 described above, by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate), a liquid crystal display element as a micro device is formed. In the following, referring to the flowchart of FIG.
An example of the technique at this time will be described. In FIG. 11, in a pattern forming step 401, a so-called photolithography step of transferring and exposing a reticle pattern onto a photosensitive substrate (eg, a glass substrate coated with a resist) using the exposure apparatus of the present embodiment is performed. By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. After that, the exposed substrate is
A predetermined pattern is formed on the substrate by going through the respective steps such as a developing step, an etching step, and a reticle peeling step, and the process proceeds to the next color filter forming step 402.

Next, in the color filter forming step 402, 3 colors corresponding to R (Red), G (Green), and B (Blue)
A set of one dot forms a color filter in which a large number is arranged in a matrix. Then, after the color filter forming step 402, a cell assembling step 403 is performed. In the cell assembly step 403, a liquid crystal panel (liquid crystal cell) is assembled using the substrate having the predetermined pattern obtained in the pattern formation step 401, the color filter obtained in the color filter formation step 402, and the like. In the cell assembling step 403, for example, a liquid crystal is injected between the substrate having the predetermined pattern obtained in the pattern forming step 401 and the color filter obtained in the color filter forming step 402, and a liquid crystal panel <liquid crystal cell >

Then, in a module assembling step 404, components such as an electric circuit and a backlight for performing a display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete a liquid crystal display element. According to the above-described method for manufacturing a liquid crystal display element, a liquid crystal display element having an extremely fine circuit pattern can be obtained with high throughput.

In the above-described embodiment, the diffractive optical element as the light beam conversion optical system can be configured to be positioned in the illumination light path by, for example, a turret method. In addition, for example, a known slider mechanism can be used to insert and remove the above-described diffractive optical element and to switch the diffractive optical element. Incidentally, a detailed description of the diffractive optical element that can be used in the present invention is described in U.S. Pat.
It is disclosed in Japanese Patent Publication No. 300 and the like. In the above embodiment, a diffractive optical element is used as the light beam conversion optical system. However, a wavefront splitting optical integrator such as a fly-eye lens or a micro fly-eye may be used.

Further, in the above embodiment, a micro fly's eye or a rod type integrator is used as the multiple light source forming means, but other suitable optical components such as a fly's eye lens or a diffractive optical element can be used. . In the above-described first and second embodiments, an illumination field is once formed on a predetermined surface conjugate with the mask 10, and a light flux from this illumination field is restricted by the mask blind 8. An illumination field is formed on the mask 10 via the mask.
However, a configuration is also possible in which the relay optical system 9 is omitted and the illumination field is directly formed on the mask 10 disposed at the position of the mask blind 8 via the zoom lens 7 or 70.

Further, in the third embodiment described above, the configuration is such that a circular light beam is made incident on the rod-type integrator 500 having a rectangular cross section. However, in order to increase the filling rate of the incident light beam, an ellipse is used. It is preferable that the light beam is converted into a light beam and incident. Note that the rod-type integrator may be a single solid glass rod, or may be a form in which a reflection mirror is assembled in a tunnel shape. When a rod-type integrator is formed by a reflection mirror, the cross-sectional size d5 can be changed as necessary.

In the above embodiment, the aperture stop for restricting the luminous flux of the secondary light source is arranged near the rear focal plane of the micro fly's eye. However, in some cases, a configuration is possible in which the cross-sectional area of each microlens constituting the micro fly's eye is set to be sufficiently small, so that the arrangement of the aperture stop is omitted and the light flux of the secondary light source is not restricted at all.

Further, in the above-described embodiment, an example is shown in which a quadrupole secondary light source is formed.
It is also possible to form a secondary light source having a multi-pole shape such as a (second) light source or an 8-pole (eighth) shape. Also,
In the above-described embodiment, the present invention has been described by taking the projection exposure apparatus having the illumination optical device as an example. Obviously you can do that.

In this embodiment, since the exposure light having a wavelength of 180 nm or more, such as a KrF excimer laser (wavelength: 248 nm) or an ArF excimer laser (wavelength: 193 nm), is used as the light source, the diffractive optical element is made of, for example, quartz. It can be formed of glass. When a wavelength of 200 nm or less is used as the exposure light, the diffractive optical element may be made of fluorite, quartz glass doped with fluorine, quartz glass doped with fluorine and hydrogen, having a structure determination temperature of 1200 K or less and an OH group. Quartz glass with a concentration of 1000 ppm or more, a structure determination temperature of 1200 K or less, and a hydrogen molecule concentration of 1 × 10 ¹⁷ mole
quartz glass with cules / cm ³ or more, structure determination temperature 12
Quartz glass having a temperature of 1200 K or less, a hydrogen molecule concentration of 1 × 10 ¹⁷ molecules / cm ³ or more, and a chlorine concentration of 50 p or less.
It is preferably formed of a material selected from the group of quartz glass having a value of pm or less.

A quartz glass having a structure determination temperature of 1200 K or less and an OH group concentration of 1000 ppm or more is disclosed in Japanese Patent No. 2770224 by the present applicant. Quartz glass having a molecular concentration of 1 × 10 ¹⁷ molecules / cm ³ or more, quartz glass having a structure determination temperature of 1200 K or less and a chlorine concentration of 50 ppm or less, and a structure determination temperature of 1200 K or less and a hydrogen molecule concentration of 1 × 10 ¹⁷ molecu
Quartz glass having a les / cm ³ or more and a chlorine concentration of 50 ppm or less is disclosed in Japanese Patent No. 2936138 by the present applicant.

[0127]

As described above, in the illumination optical apparatus according to the present invention, by controlling the focal lengths or magnifications of the first variable power optical system and the second variable power optical system, the light amount loss can be suppressed well. , The illumination NA and the size of the illumination area can be adjusted to desired values. Therefore, in the exposure apparatus incorporating the illumination optical device of the present invention, the size of the exposure area and the σ value can be adjusted to desired values while satisfactorily suppressing the light amount loss in the aperture stop and the illumination field stop. As a result, in the exposure apparatus of the present invention, the size of the illumination area (exposure area) and the σ value are set to optimal values according to the characteristics of the microdevice to be manufactured or the characteristics of the mask to be used. In addition, good projection exposure with high throughput can be performed under high exposure illuminance and good exposure conditions.

Further, in the exposure method for exposing the pattern of the mask arranged on the surface to be irradiated to the photosensitive substrate using the illumination optical apparatus of the present invention or the method for manufacturing a microdevice, the exposure method is performed under favorable exposure conditions. , It is possible to manufacture a good microdevice. In addition, according to an exemplary embodiment of the present invention, a modified illumination such as an annular modified illumination or a quadrupole modified illumination and a normal circular illumination can be achieved while satisfactorily suppressing the light amount loss in the aperture stop for limiting the secondary light source. Lighting can be performed. Therefore, in the exposure apparatus incorporating the illumination optical apparatus of the present invention, the resolution and depth of focus of the projection optical system suitable for the fine pattern to be exposed and projected can be obtained by appropriately changing the type of the modified illumination. As a result, good projection exposure with high throughput can be performed under high exposure illuminance and good exposure conditions.

In order to set a desired exposure condition or a desired illumination condition, the light beam for exposure was converted by the light beam conversion means (change means) into a light beam having a desired light intensity distribution, so that the illumination numerical aperture changed. Also, since the illumination numerical aperture can be adjusted by the adjusting means, an exposure apparatus and a micro exposure apparatus capable of exposing a photosensitive substrate such as a wafer to a mask pattern that is always good under a desired exposure condition or a desired illumination condition. A device manufacturing method can be realized.

[Brief description of the drawings]

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

FIG. 2 is a perspective view illustrating the internal configuration and operation of the optical delay unit 2 of FIG.

FIG. 3 illustrates a relationship between focal lengths of a zoom lens 4 and a zoom lens 7, a size of a rectangular illumination field formed on a predetermined surface conjugate with a mask 10, and an illumination NA in the first embodiment. FIG.

FIG. 4 is a diagram illustrating an operation of a diffractive optical element 3a for annular deformation illumination.

FIG. 5 is a diagram for explaining the function of a diffractive optical element 3b for quadrupole deformation illumination.

FIG. 6 is a view schematically showing a configuration of an exposure apparatus including an illumination optical device according to a second embodiment of the present invention.

FIG. 7 shows the relationship between the focal length of the zoom lens 4 and the micro fly's eye group 50, the size of a rectangular illumination field formed on a predetermined surface conjugate with the mask 10, and the illumination NA in the second embodiment. FIG.

FIG. 8 is a view schematically showing a configuration of an exposure apparatus including an illumination optical device according to a third embodiment of the present invention.

FIG. 9 is a diagram illustrating the relationship between the magnification of the zoom lens 41 and the zoom lens 71, the size of a rectangular illumination field formed on a predetermined surface conjugate with the mask 10, and the illumination NA in the third embodiment. It is.

FIG. 10 is a flowchart showing an example of a technique for obtaining a semiconductor device as a micro device.

FIG. 11 is a flowchart showing an example of a method for obtaining a liquid crystal display element as a micro device.

[Explanation of symbols]

 Reference Signs List 1 light source 2 optical delay unit 3 diffractive optical element 4 zoom lens 5 micro fly eye 6 aperture stop 7 zoom lens 8 mask blind 9 relay optical system 10 mask 11 projection optical system 12 wafer 13 wafer stage 20 input means 21 control system 22 to 25 Drive system

Claims (14)

[Claims] 1. An illumination optical device for illuminating a surface to be illuminated, a first variable power optical system having a variable focal length or a magnification for adjusting an illumination numerical aperture on the surface to be illuminated, and formed on the surface to be illuminated. An illumination optical device, comprising: a second variable power optical system having a variable focal length or a variable magnification for changing the size of an illumination area to be irradiated. 2. Adjusting each focal length or each magnification of the first variable power optical system and the second variable power optical system to set the illumination numerical aperture and the size of the illumination area to desired values, respectively. The illumination optical device according to claim 1, further comprising an adjustment system for performing the adjustment. 3. Light source means for supplying illumination light; multi-light source forming means for forming a large number of light fluxes based on the illumination light; and light flux having a predetermined sectional shape from the light flux from the light source means. Wherein the first variable power optical system guides the light beam passing through the light beam converting optical system to the multiple light source forming unit, and wherein the second variable power optical system includes: 2. The light source according to claim 1, wherein a large number of light beams from the multiple light source forming means are guided to the surface to be irradiated.
Or the illumination optical device according to 2. 4. A first variable power optical system, comprising: light source means for supplying illumination light; and a light beam conversion optical system for converting a light beam from the light source means into a light beam having a predetermined sectional shape. Guides the light beam from the light beam conversion optical system to the second variable power optical system, and the second variable power optical system forms a large number of light beams based on the light beam passing through the first variable power optical system. 3. The illumination optical system according to claim 1, wherein the second variable power optical system guides a light beam from the first variable power optical system to the surface to be irradiated. 4. apparatus. 5. The illumination optical device according to claim 1, wherein the projection optical system projects and exposes a pattern of a mask disposed on the surface to be irradiated onto a photosensitive substrate. An exposure apparatus, comprising: 6. A step of illuminating a mask arranged on the surface to be illuminated by the illumination optical device according to claim 1, and illuminating a pattern of the illuminated mask on a photosensitive substrate. And a step of transferring.
Manufacturing method of micro device. 7. An exposure apparatus comprising: an illumination optical device that illuminates a mask pattern having a predetermined pattern with a light beam for exposure; and a projection system that projects and exposes a pattern image of the mask onto a photosensitive substrate. Input means for inputting information on an exposure condition on the reactive substrate or an illumination condition on the mask, the illumination optical device converts the light beam for exposure into a desired light intensity distribution based on input information from the input means. A light beam converting means for converting the light beam into a light beam having a first variable magnification optical system for adjusting an illumination numerical aperture of the mask based on input information from the input means; and An exposure apparatus comprising: a second variable power optical system that changes the size of an illumination area formed on the mask. 8. The illumination optical device includes an optical integrator that uniformly illuminates the mask, the first variable power optical system is disposed on an incident side of the optical integrator, and the second variable power optical system. 8. The system according to claim 7, wherein the system is arranged on an emission side of the optical integrator.
3. The exposure apparatus according to claim 1. 9. A method for manufacturing a micro device, comprising: an illumination step of illuminating a pattern of a mask having a predetermined pattern with a light beam for exposure; and an exposure step of projecting and exposing a pattern image of the mask onto a photosensitive substrate. The illumination step is an input step of inputting information on an exposure condition on the photosensitive substrate or an illumination condition on the mask, and a desired light intensity distribution of a light beam for exposure based on input information from the input step. A light beam converting step of converting the light beam into a light beam having an illumination area; an illumination area changing step of changing a size of an illumination area formed on the mask based on the input information from the input step; An adjusting step of adjusting an illumination numerical aperture of the mask. 10. The method according to claim 9, wherein the adjusting step includes correcting the value of the illumination numerical aperture changed by the illumination area changing step to keep the value of the illumination numerical aperture substantially constant. A manufacturing method of the microdevice according to the above. 11. An exposure apparatus comprising: an illumination optical device that illuminates a mask pattern having a predetermined pattern with a light beam for exposure; and a projection system that projects and exposes a pattern image of the mask onto a photosensitive substrate. An optical device, a changing unit for changing a light intensity distribution at or near a pupil position of the illumination optical device, and an adjusting unit for adjusting an illumination numerical aperture of the mask in accordance with a change in the light intensity distribution by the changing unit. An exposure apparatus comprising: 12. The apparatus according to claim 1, wherein the changing unit includes a light beam converting unit for selectively converting the light beam for exposure into one of a plurality of light beams having different light intensity distributions. Item 12. An exposure apparatus according to Item 11. 13. A light beam converting means, comprising: a first diffractive optical member forming a first light intensity distribution; and a first diffractive optical member provided in an optical path so as to be exchangeable with the first diffractive optical member. The exposure apparatus according to claim 12, further comprising a second diffractive optical member that forms a different second light intensity distribution. 14. A micro process comprising: an illumination step of illuminating a pattern of a mask having a predetermined pattern using an illumination optical device; and an exposure step of projecting and exposing a pattern image of the mask on a photosensitive substrate using a projection system. In the method for manufacturing a device, the illumination step includes: a change step of changing a light intensity distribution at or near a pupil position of the illumination optical device; An adjustment step of adjusting a numerical aperture.