JP2006128366A - Aligner, exposure method and manufacturing method of device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scanning aligner where the exposure amount on a photosensitive substrate can properly be adjusted in accordance with a comparatively simple structure, even though EUV light is used as the exposure light and a reflecting mask is used. <P>SOLUTION: The aligner is provided with an illumination system for illuminating the mask (M), where a prescribed pattern is disposed, and a projection optical system (PL) for forming a pattern image of the mask on the photosensitive substrate (W) and where the mask and the photosensitive substrate are relatively moved with respect to the projection optical system along a prescribed direction, and the pattern of the mask is projected/exposed onto the photosensitive substrate. The illumination system has a pulse luminescence type optical source (11), a field stop (21), which is arranged in a position close to the mask and regulates an illumination region on the mask, and a shielding member for shielding a part of light flux passing the field stop. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an exposure apparatus, an exposure method, and a device manufacturing method. More particularly, the present invention relates to adjustment of exposure amount in a scanning exposure apparatus used for manufacturing a microdevice such as a semiconductor element, an imaging element, a liquid crystal display element, and a thin film magnetic head in a lithography process. is there.

2. Description of the Related Art Conventionally, in an exposure apparatus used for manufacturing a semiconductor element or the like, a circuit pattern formed on a mask (reticle) is projected and transferred onto a photosensitive substrate (for example, a wafer) via a projection optical system. A resist is coated on the photosensitive substrate, and the resist is exposed by projection exposure through the projection optical system, and a resist pattern corresponding to the mask pattern is obtained. Here, the resolving power W of the exposure apparatus depends on the wavelength λ of the exposure light and the numerical aperture NA of the projection optical system, and is expressed by the following equation (a).
W = k · λ / NA (k: constant) (a)

  Therefore, in order to improve the resolving power of the exposure apparatus, it is necessary to shorten the wavelength λ of the exposure light and increase the numerical aperture NA of the projection optical system. In general, it is difficult to increase the numerical aperture NA of the projection optical system to a predetermined value or more from the viewpoint of optical design, and therefore it is necessary to shorten the wavelength of the exposure light. Therefore, as a next-generation exposure method (exposure apparatus) for semiconductor patterning, an EUVL (Extreme UltraViolet Lithography) technique has been attracting attention.

  In the EUVL exposure apparatus, EUV (Extreme UltraViolet) light having a wavelength of about 5 to 20 nm as compared with a conventional exposure method using a KrF excimer laser light having a wavelength of 248 nm or an ArF excimer laser light having a wavelength of 193 nm. Is used. When EUV light is used as the exposure light, there is no optically transmissive optical material that can be used. For this reason, an EUVL exposure apparatus inevitably uses a reflective mask and a reflective projection optical system.

  By the way, in a scanning type (scan type) exposure apparatus, a slit-like (elongated rectangular shape, arc shape, etc.) region is illuminated on a mask provided with a predetermined pattern, and the mask and photosensitivity to the projection optical system. While the substrate is relatively moved in a predetermined direction (scanning direction), the mask pattern is scanned and exposed on the photosensitive substrate (scan exposure). Here, the illuminance distribution in the slit-like exposure area on the photosensitive substrate in the stationary state, that is, the static exposure area is almost uniform, and the slit-like illumination area on the mask and the slit-like static exposure area on the photosensitive substrate The width dimension along the scanning direction is constant along the scanning orthogonal direction orthogonal to the scanning direction.

  Conventionally, in a scanning type exposure apparatus that uses a transmissive mask, for example, a scanning type exposure apparatus that uses KrF excimer laser light or ArF excimer laser light as exposure light, the illuminance distribution in the stationary exposure region is substantially along the scanning orthogonal direction. In the scanning direction of the slit-shaped opening (light transmitting portion) of the field stop arranged at a position defocused to some extent from the optically conjugate position with the mask (and thus the photosensitive substrate). The exposure amount on the photosensitive substrate was adjusted by changing the width dimension along the scanning orthogonal direction.

  However, in the EUVL exposure apparatus, it is difficult to apply a method for adjusting the exposure amount by changing the width dimension of the slit-shaped opening of the field stop. This point will be briefly described below. Since a light source that supplies EUV light is generally a pulse light source, (static exposure area width) / (scan speed) must be an integral multiple of the light emission interval of the light source. Here, the width of the static exposure area is a width dimension along the scanning direction of the slit-shaped static exposure area, and the scanning speed is a speed at which the photosensitive substrate moves in the scanning direction during the scanning exposure.

  In a scanning type exposure apparatus using a transmission type mask, a sufficient distance is secured between the mask and the field stop. Therefore, as described above, the field stop is set at a position defocused to some extent from the position conjugate with the mask. Due to the defocusing effect of this field stop, a substantially uniform exposure dose distribution can be obtained on the photosensitive substrate even if (static exposure area width) / (scanning speed) is not strictly an integral multiple of the light emission interval. It is done. In other words, due to the defocus effect of the field stop, a certain tolerance is obtained for the width of the static exposure region, and consequently a certain tolerance is also obtained for the width of the opening of the field stop. This makes it possible to adjust the exposure amount by changing the width dimension of the opening.

  On the other hand, in the EUVL exposure apparatus using a reflective mask, the illumination light beam is incident on the reflective mask from an oblique direction. Therefore, if the field stop is not arranged as close as possible to the mask, the reflected light is reflected from the mask. The imaging light beam is blocked by the field stop, which adversely affects the imaging on the photosensitive substrate. That is, in the EUVL exposure apparatus, since the defocus effect of the field stop cannot be obtained, (static exposure area width) / (scan speed) needs to be almost strictly an integral multiple of the light emission interval. It becomes difficult to apply a method of adjusting the exposure amount by changing the width dimension of the opening of the shape.

  The present invention has been made in view of the above-described problems. For example, although EUV light is used as exposure light and a reflective mask is used, the present invention can be applied to a photosensitive substrate according to a relatively simple structure. It is an object of the present invention to provide a scanning type exposure apparatus and exposure method capable of satisfactorily adjusting the exposure amount.

In order to solve the above problems, in the first embodiment of the present invention, an illumination system for illuminating a mask provided with a predetermined pattern, and projection optics for forming a pattern image of the mask on a photosensitive substrate. An exposure apparatus for projecting and exposing a pattern of the mask onto the photosensitive substrate by relatively moving the mask and the photosensitive substrate along a predetermined direction with respect to the projection optical system,
The illumination system includes a pulse emission type light source and a field of view for defining an illumination area on the mask disposed at a position close to the mask, a position optically conjugate with the mask, or a position in the vicinity thereof. There is provided an exposure apparatus comprising: a stop; and a light shielding member for blocking a light beam that has passed through the field stop or a part of the light beam that has passed through the field stop.

In the second embodiment of the present invention, a mask provided with a predetermined pattern is illuminated with light from a pulsed light source, and the mask and the photosensitive substrate are moved relative to the projection optical system along a predetermined direction. In the exposure method of projecting and exposing the pattern of the mask onto the photosensitive substrate,
A light beam that passes through a field stop for defining an illumination area on the mask or a position close to the mask, a position optically conjugate with the mask, or a position near the mask, or passes through the field stop. An exposure method is provided in which a part of a light beam is blocked by a light blocking member.

In the third embodiment of the present invention, an exposure step of exposing the pattern of the mask onto the photosensitive substrate using the exposure apparatus of the first embodiment or the exposure method of the second embodiment;
And a development step of developing the photosensitive substrate exposed through the exposure step. A device manufacturing method is provided.

  In the present invention, for example, when the illuminance distribution in the arc-shaped still exposure region becomes substantially non-uniform along the scanning orthogonal direction, the light shielding member having a shape corresponding to the non-uniform illuminance distribution is placed immediately before the field stop. The exposure amount in the shot area on the photosensitive substrate can be adjusted by the action of the shadow in the defocused state of the light shielding member formed in the arc-shaped static exposure area on the photosensitive substrate. That is, in the exposure apparatus and the exposure method of the present invention, although the EUV light is used as the exposure light and the reflective mask is used, the exposure amount adjustment on the photosensitive substrate is excellent according to a relatively simple configuration. Thus, a good device can be manufactured based on good scanning exposure.

  Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a view schematically showing the overall configuration of an exposure apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing the internal configuration of the light source, illumination optical system, and projection optical system of FIG. In FIG. 1, the Z axis along the optical axis direction of the projection optical system, that is, the normal direction of the wafer as the photosensitive substrate, the Y axis in the direction parallel to the paper surface of FIG. The X axis is set in the direction perpendicular to the paper surface of FIG.

  Referring to FIG. 1, the exposure apparatus of this embodiment includes, for example, a laser plasma light source 1 as a light source for supplying exposure light. The light emitted from the light source 1 enters the illumination optical system 2 via a wavelength selection filter (not shown). Here, the wavelength selection filter has a characteristic of selectively transmitting only EUV light having a predetermined wavelength (for example, 13.4 nm or 11.5 nm) from light supplied from the light source 1 and blocking transmission of other wavelength light. . The EUV light 3 that has passed through the wavelength selection filter illuminates a reflective mask (reticle) M on which a pattern to be transferred is formed, via an illumination optical system 2 and a plane reflecting mirror 4 as an optical path deflecting mirror.

  The mask M is held by a mask stage 5 that can move along the Y direction so that its pattern surface extends along the XY plane. The movement of the mask stage 5 is configured to be measured by a laser interferometer 6. The light from the illuminated pattern of the mask M forms an image of the mask pattern on the wafer W, which is a photosensitive substrate, via the reflective projection optical system PL. That is, on the wafer W, as will be described later, for example, an arcuate still exposure region (effective exposure region) that is symmetrical with respect to the Y axis is formed.

  The wafer W is held by a wafer stage 7 that can move two-dimensionally along the X and Y directions so that the exposure surface extends along the XY plane. The movement of the wafer stage 7 is measured by a laser interferometer 8 as in the mask stage 5. Thus, scanning exposure (scan exposure) is performed while the mask stage 5 and the wafer stage 7 are moved along the Y direction, that is, while the mask M and the wafer W are moved relative to the projection optical system PL along the Y direction. As a result, the pattern of the mask M is transferred to one rectangular shot area of the wafer W.

  At this time, when the projection magnification (transfer magnification) of the projection optical system PL is, for example, 1/4, the moving speed of the wafer stage 7 is set to 1/4 of the moving speed of the mask stage 5 to perform synchronous scanning. Further, by repeating scanning exposure while moving the wafer stage 7 two-dimensionally along the X direction and the Y direction, the pattern of the mask M is sequentially transferred to each shot area of the wafer W.

  Referring to FIG. 2, in the laser plasma light source 1, light (non-EUV light) emitted from the laser light source 11 is condensed on the gas target 13 via the condenser lens 12. Here, a high-pressure gas made of, for example, xenon (Xe) is supplied from the nozzle 14, and the gas injected from the nozzle 14 forms the gas target 13. The gas target 13 obtains energy from the focused laser beam, turns it into plasma, and emits EUV light. The gas target 13 is positioned at the first focal point of the elliptical reflecting mirror 15. Therefore, the EUV light emitted from the laser plasma light source 1 is collected at the second focal point of the elliptical reflecting mirror 15. On the other hand, the gas that has finished emitting light is sucked through the duct 16 and guided to the outside.

  The EUV light collected at the second focal point of the elliptical reflecting mirror 15 becomes a substantially parallel light beam via the concave reflecting mirror 17 and is guided to the optical integrator 18 including a pair of fly-eye mirrors 18a and 18b. The fly-eye mirrors 18a and 18b are configured by, for example, arranging a large number of concave mirror elements having an arcuate outer shape vertically and horizontally and densely. As the pair of fly-eye mirrors 18a and 18b, for example, the fly-eye mirror disclosed by the present applicant in JP-A-11-312638 can be used. For more detailed configuration and operation of the fly-eye mirror, reference can be made to related descriptions in the publication.

  Thus, a substantial surface light source having a predetermined shape is formed in the vicinity of the reflection surface of the second fly-eye mirror 18b, that is, in the vicinity of the exit surface of the optical integrator 18 (18a, 18b). Here, the substantial surface light source is formed at or near the exit pupil position of the illumination optical system 2, that is, the surface optically conjugate with the entrance pupil of the projection optical system PL or the vicinity thereof. Light from a substantial surface light source is emitted from the illumination optical system 2 via a condenser optical system (19, 20) constituted by a convex reflecting mirror 19 and a concave reflecting mirror 20.

  The light emitted from the illumination optical system 2 is deflected by the plane reflecting mirror 4, and then passes through the arc-shaped opening (light transmission portion) of the field stop 21 disposed substantially parallel to and close to the mask M. Thus, an arcuate illumination area is formed on the mask M. Thus, the light source 1 (11 to 16), the illumination optical system 2 (17 to 20), the plane reflecting mirror 4, and the field stop 21 are illumination systems for Koehler illumination of the mask M provided with a predetermined pattern. It is composed.

  The light from the illuminated pattern of the mask M forms an image of the mask pattern in an arcuate static exposure region on the wafer W via the projection optical system PL. The projection optical system PL forms a first reflective imaging optical system for forming an intermediate image of the mask M pattern and an image of the mask pattern intermediate image (secondary image of the mask M pattern) on the wafer W. And a second reflection imaging optical system. The first reflective imaging optical system is constituted by four reflecting mirrors M1 to M4, and the second reflective imaging optical system is constituted by two reflecting mirrors M5 and M6. The projection optical system PL is an optical system telecentric on the wafer side (image side).

  FIG. 3 is a diagram schematically illustrating one scanning exposure in the present embodiment. Referring to FIG. 3, when the pattern of the mask M is transferred to one rectangular shot region SR of the wafer W by one scanning exposure (scanning exposure), an arcuate stationary exposure region (symmetrical with respect to the Y axis) The effective exposure area (ER) moves from the scanning start position indicated by the solid line in the drawing to the scanning end position indicated by the broken line in the drawing. Here, the width dimension We along the scanning direction (scanning direction: Y direction) of the arc-shaped static exposure region ER on the wafer W which is the photosensitive substrate is constant along the scanning orthogonal direction (X direction).

  Therefore, the width dimension along the scanning direction of the arcuate illumination area (stationary illumination area) IR on the mask M as shown in FIG. 4A corresponding to the arcuate still exposure area ER on the wafer W. Wi is also constant along the scanning orthogonal direction, and as shown in FIG. 4B, the width dimension Ws (= Wi) along the scanning direction of the arcuate opening 21a of the field stop 21 is also along the scanning orthogonal direction. Is constant. Further, the ratio We / Vw of the width dimension We along the scanning direction of the static exposure region ER with respect to the moving speed Vw of the wafer W in the scanning direction is set to be approximately an integral multiple of the light emission interval of the light source 1.

  As described above, in a scanning exposure apparatus using a transmissive mask, for example, when the illuminance distribution in the arc-shaped still exposure region becomes substantially non-uniform along the scanning orthogonal direction, this non-uniform illuminance is obtained. Depending on the distribution, the width dimension along the scanning direction of the arc-shaped opening of the field stop arranged at a position defocused to some extent from the position conjugate with the mask (and thus the photosensitive substrate) changes along the scanning orthogonal direction. By adjusting the exposure amount, the exposure amount on the photosensitive substrate was adjusted.

  Specifically, as shown in FIG. 5, when the illuminance distribution in the arc-shaped still exposure region ER is the smallest on the right side in the figure and the illuminance monotonously increases toward the left side in the figure, In FIG. 2, a deformed arc-shaped static exposure region ER is formed on the photosensitive substrate so that the width dimension along the scanning direction (vertical direction in the figure) is the largest and the width dimension monotonously decreases toward the left side in the figure. In addition, by changing the width dimension along the scanning direction of the aperture of the field stop appropriately along the scanning orthogonal direction, the aperture of the field stop also has a modified arc shape corresponding to the stationary arc-shaped still exposure region ER. It was set to.

  However, as described above, in the EUVL exposure apparatus using the reflective mask M, the illumination light beam is incident on the reflective mask M from an oblique direction. Therefore, as shown in FIG. 2, if the field stop 21 is not disposed as close as possible to the mask M, the imaging light beam reflected from the mask M is blocked by the field stop 21 and forms an image on the wafer W. It will have an adverse effect. That is, in the EUVL exposure apparatus, since the defocus effect of the field stop 21 cannot be obtained, it is difficult to adjust the exposure amount by changing the width dimension of the arcuate opening 21a of the field stop 21.

  Therefore, in the present embodiment, as shown in FIG. 6A, a light shielding member 22 (not shown in FIG. 1 for clarity of illustration) for blocking a part of the light beam passing through the field stop 21 is provided. It is arranged immediately before the field stop 21. More specifically, the field stop 21 is disposed in close proximity to a position optically conjugate with the wafer W (that is, the position of the pattern surface of the mask M), but the light shielding member 22 is located to some extent from the conjugate position of the wafer W. Arranged at the defocused position. The light shielding member 22 is made of, for example, a suitable metal material that is excellent in workability and that does not substantially generate harmful gas in a vacuum when irradiated with EUV light.

  Further, as shown in FIG. 6B, the light shielding member 22 is in an arc-shaped still exposure region on the wafer W (that is, corresponding to a substantially clear focus image of the arc-shaped opening 21a of the field stop 21) ER. The defocused shadow 22a is formed such that the width dimension along the scanning direction (vertical direction in the figure) changes along the scanning orthogonal direction (horizontal direction in the figure). In other words, the light shielding member 22 has a shape such that the light shielding width changes along the longitudinal direction of the arcuate opening 21 a of the field stop 21.

  Thus, in the exposure apparatus of this embodiment, for example, when the illuminance distribution in the arc-shaped still exposure region ER becomes substantially non-uniform along the scanning orthogonal direction, the exposure apparatus has a shape corresponding to the non-uniform illuminance distribution. A scanning exposure apparatus using a transmissive mask with the light shielding member 22 disposed immediately before the field stop 21 and the action of the defocus shadow 22a of the light shielding member 22 formed in the arc-shaped static exposure region ER on the wafer W. The exposure amount in the shot region SR on the wafer W can be adjusted in the same manner as in the step of setting the aperture of the field stop in a deformed arc shape. That is, in the exposure apparatus of the present embodiment, although the EUV light is used as the exposure light and the reflective mask M is used, the exposure amount on the wafer W is well adjusted according to a relatively simple configuration. be able to.

  In the above-described embodiment, the defocused shadow 22a of the light shielding member 22 formed in the arc-shaped still exposure region ER on the wafer W extends in the scanning orthogonal direction substantially at the center along the scanning direction, that is, the light shielding. It is preferable that the member 22 is arranged corresponding to a substantially central position along the short direction of the arcuate illumination area formed in the mask M. With this configuration, although the illumination light incident on the mask M has various incident angles, it is possible to satisfactorily suppress the deterioration of the imaging performance caused by the light shielding member 22.

In the above-described embodiment, it is preferable that the distance Ds between the mask M and the light shielding member 22 (see FIG. 6A) satisfies the following conditional expression (1). In conditional expression (1), NAi is the numerical aperture of the illumination light that illuminates the mask M, and Wi is the dimension (width dimension) of the arcuate illumination area IR formed on the mask M as described above. Df (see FIG. 6A) is the distance between the mask M and the field stop 21.
Df <Ds ≦ Wi / (2 × NAi) (1)

  Exceeding the upper limit value of conditional expression (1) is not preferable because the distance Ds between the mask M and the light shielding member 22 becomes too large, and the imaging performance tends to deteriorate due to the light shielding member 22. As described above, since the light shielding member 22 needs to be disposed at a position defocused to some extent from the conjugate position of the wafer W (that is, the position of the pattern surface of the mask M) immediately before the field stop 21, the present invention. In this case, the lower limit of conditional expression (1) is not exceeded.

  By the way, in the above-described embodiment, the defocusing of the light shielding member formed in the arc-shaped still exposure region ER on the wafer W is performed by replacing the light shielding member 22 having a predetermined shape with another light shielding member having a different shape, for example. By changing the shape of the shadow, the exposure amount on the wafer W can be adjusted in accordance with various illuminance distributions in the static exposure region ER. Further, the light shielding member 22 is formed in the arc-shaped stationary exposure region ER on the wafer W by moving along the arc-shaped trajectory corresponding to the longitudinal direction (scanning orthogonal direction) of the arc-shaped illumination region IR. By changing the shape of the defocused shadow 22a of the light shielding member 22, the exposure amount on the wafer W can be adjusted in accordance with various illuminance distributions in the static exposure region ER.

  Further, the exposure amount on the wafer W can be adjusted in accordance with various illuminance distributions in the static exposure region ER by using the light shielding member made up of the relatively movable first light shielding member and the second light shielding member. . Specifically, the defocus shadow of the first light shielding member and the defocus shadow of the second light shielding member formed in the arc-shaped static exposure region ER on the wafer W are partially overlapped or partially The exposure amount can be adjusted by relatively shifting the position while maintaining the superimposed state.

  Alternatively, for example, the first light-shielding member and the second light-shielding member, each having a shape in which the light-shielding width changes according to a predetermined function and spaced apart, are arranged in the longitudinal direction (scanning orthogonal direction) of the arcuate illumination region IR. The amount of exposure can be adjusted by making a relative movement along the arcuate trajectory. At this time, for example, the n-order component of the illuminance distribution in the still exposure region ER is controlled by relatively moving the first light-shielding member and the second light-shielding member whose light-shielding width changes according to the (n + 1) th power series. can do.

  In the above-described embodiment, the present invention is applied to the EUVL exposure apparatus that uses the reflective mask M. However, the present invention is not limited to this, and a pulse emission type light source and a reflective mask are used. The present invention is similarly applied to other appropriate scanning type exposure apparatuses, and the present invention is also applied to an appropriate scanning type exposure apparatus using a pulse emission type light source and a transmission type mask. Can be. However, when a transmission type mask is used, a field stop is disposed at a position optically conjugate with the mask or in the vicinity thereof to block a part of the light beam that has passed through the field stop or the light beam that has passed through the field stop. The light shielding member is positioned by defocusing to some extent from the conjugate position of the mask.

  In the exposure apparatus according to the above-described embodiment, the illumination system illuminates the mask (illumination process), and exposes the transfer pattern formed on the mask using the projection optical system onto the photosensitive substrate (exposure process). Microdevices (semiconductor elements, imaging elements, liquid crystal display elements, thin film magnetic heads, etc.) can be manufactured. Hereinafter, referring to the flowchart of FIG. 7 for an example of 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 of the present embodiment. I will explain.

  First, in step 301 of FIG. 7, 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 one lot of wafers. Thereafter, in step 303, using the exposure apparatus of the present embodiment, the pattern image on the mask (reticle) is sequentially exposed and transferred to each shot area on the wafer of one lot via the projection optical system. .

  Thereafter, in step 304, the photoresist on the one lot of wafers is developed, and in step 305, the resist pattern is etched on the one lot of wafers to form a pattern on the mask. Corresponding circuit patterns are formed in each shot area on each wafer. Thereafter, a device pattern such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer. According to the semiconductor device manufacturing method described above, a semiconductor device having an extremely fine circuit pattern can be obtained with high throughput.

  In the EUVL exposure apparatus according to the above-described embodiment, a laser plasma light source is used as a light source for supplying EUV light. However, without being limited thereto, other suitable light sources that supply EUV light, such as synchrotron radiation (SOR) light sources, can also be used.

It is a figure which shows schematically the structure of the exposure apparatus concerning embodiment of this invention. It is a figure which shows schematically the internal structure of the light source of FIG. 1, an illumination optical system, and a projection optical system. It is a figure which illustrates schematically one scanning exposure in this embodiment. It is a figure which shows roughly the shape of the arc-shaped illumination area | region on a mask, and the arc-shaped opening part of a field stop. It is a figure which illustrates roughly an example of the adjustment method of the exposure amount in the scanning exposure apparatus using a transmissive mask. It is a figure which shows roughly the characteristic principal part structure in this embodiment. It is a figure which shows the flowchart about an example of the method at the time of obtaining the semiconductor device as a microdevice.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser plasma light source 2 Illumination optical system 5 Mask stage 7 Wafer stage 11 Laser light source 13 Gas target 14 Nozzle 15 Elliptic reflection mirror 18a, 18b Fly eye mirror 21 Field stop 21a Opening part 22 Light-shielding member 22a Defocus shadow M Mask PL Projection optics System W Wafer ER Static exposure area

Claims (14)

An illumination system for illuminating a mask provided with a predetermined pattern, and a projection optical system for forming a pattern image of the mask on a photosensitive substrate, the mask and the mask with respect to the projection optical system In an exposure apparatus for projecting and exposing the pattern of the mask onto the photosensitive substrate by relatively moving the photosensitive substrate along a predetermined direction,
The illumination system includes a pulse emission type light source and a field of view for defining an illumination area on the mask disposed at a position close to the mask, a position optically conjugate with the mask, or a position in the vicinity thereof. An exposure apparatus comprising: a stop; and a light shielding member for blocking a light beam that has passed through the field stop or a part of a light beam that has passed through the field stop. The field stop is disposed in proximity to the mask;
The exposure apparatus according to claim 1, wherein the light blocking member is disposed immediately before the field stop so as to block a part of a light beam passing through the field stop. 3. The exposure according to claim 1, wherein the light shielding member is arranged such that a width dimension along a scanning direction in which the mask moves changes along a direction orthogonal to the scanning direction. apparatus. 4. The exposure apparatus according to claim 1, wherein the light shielding member is disposed corresponding to a substantially central position along a short direction of the illumination area. 5. The numerical aperture of illumination light for illuminating the mask is NAi, the short dimension of the illumination area is Wi, the distance between the mask and the field stop is Df, and the distance between the mask and the light shielding member is When Ds
Df <Ds ≦ Wi / (2 × NAi)
The exposure apparatus according to claim 2, wherein the following condition is satisfied. 6. The exposure apparatus according to claim 1, wherein the light shielding member is configured to be exchangeable with another light shielding member having a different shape. The exposure apparatus according to claim 1, wherein the light shielding member is configured to be movable in correspondence with a longitudinal direction of the illumination area. The exposure apparatus according to claim 1, wherein the light shielding member includes a first light shielding member and a second light shielding member that are relatively movable. 9. The exposure apparatus according to claim 1, wherein the optical system between the light source and the photosensitive substrate constitutes a reflection optical system. A mask provided with a predetermined pattern is illuminated with light from a pulse-emitting light source, and the mask and the photosensitive substrate are moved relative to the projection optical system along a predetermined direction so that the pattern of the mask is exposed to light. In an exposure method of projecting and exposing on a conductive substrate,
A light beam that passes through a field stop for defining an illumination area on the mask or a position close to the mask, a position optically conjugate with the mask, or a position near the mask, or passes through the field stop. An exposure method characterized in that a part of a light beam is blocked by a light blocking member. Placing the field stop close to the mask;
The exposure method according to claim 10, wherein the light shielding member is disposed immediately before the field stop so as to block a part of the light beam passing through the field stop. 12. The exposure method according to claim 10, wherein the light shielding member is disposed substantially corresponding to a central position along a short direction of the illumination area. The numerical aperture of illumination light for illuminating the mask is NAi, the short dimension of the illumination area is Wi, the distance between the mask and the field stop is Df, and the distance between the mask and the light shielding member is When Ds
Df <Ds ≦ Wi / (2 × NAi)
The exposure method according to claim 11 or 12, wherein the following condition is satisfied. An exposure step of exposing the pattern of the mask to the photosensitive substrate using the exposure apparatus according to any one of claims 1 to 9 or the exposure method according to any one of claims 10 to 13.
And a development step of developing the photosensitive substrate exposed through the exposure step.

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