WO2004090955A1 - Illuminating optical device, projection exposure system and exposure method - Google Patents

Illuminating optical device, projection exposure system and exposure method Download PDF

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Publication number
WO2004090955A1
WO2004090955A1 PCT/JP2004/004835 JP2004004835W WO2004090955A1 WO 2004090955 A1 WO2004090955 A1 WO 2004090955A1 JP 2004004835 W JP2004004835 W JP 2004004835W WO 2004090955 A1 WO2004090955 A1 WO 2004090955A1
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WIPO (PCT)
Prior art keywords
optical system
fly
eye
eye optical
illumination
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PCT/JP2004/004835
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French (fr)
Japanese (ja)
Inventor
Hideki Komatsuda
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Nikon Corporation
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Application filed by Nikon Corporation filed Critical Nikon Corporation
Priority to JP2005505263A priority Critical patent/JPWO2004090955A1/en
Publication of WO2004090955A1 publication Critical patent/WO2004090955A1/en

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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/70—Microphotolithographic exposure; Apparatus therefor
    • G03F7/70058—Mask illumination systems
    • G03F7/70075—Homogenization of illumination intensity in the mask plane by using an integrator, e.g. fly's eye lens, facet mirror or glass rod, by using a diffusing optical element or by beam deflection
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
    • G21K1/06—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diffraction, refraction or reflection, e.g. monochromators

Definitions

  • the present invention relates to an illumination optical device used for manufacturing a semiconductor integrated circuit and the like, a projection exposure apparatus using the illumination optical device, and an exposure method using the projection exposure device.
  • EUV extreme ultra violet
  • illuminating optics reflective optics are used because EUV light does not pass through transmissive refraction members (glass, transmissive crystals, etc.).
  • an illumination optical device for EUVL an illumination optical device using a reflective fly-eye optical system has been proposed (for example, see Japanese Patent Application Laid-Open No. 11-312638).
  • a light beam emitted from a non-EUV light laser light source 201 and condensed by a condensing optical system 202 is emitted.
  • EUV light source 204 is obtained by hitting the target material supplied from nozzle 203.
  • the EUV light emitted from the EUV light source 204 is condensed by a condenser mirror 205, reflected by a guiding optical system 206, and then transmitted to an entrance-side reflective fly-eye optical system 207, which is an optical element in which a number of concave mirrors are arranged in parallel. Incident.
  • a large number of light beams split by the wavefront in the incident-side reflection type fly-eye optical system 207 are an optical element in which a large number of concave mirrors are arranged in parallel via an aperture stop 208 having a variable opening.
  • the light is reflected by the exit-side reflection fly-eye optical system 209, and enters the mirror 210 via the re-aperture stop 208.
  • Mirror 21 The light beam reflected at 0 is converged by the optical system 211 and irradiates the mask 212.
  • the illuminated pattern image of the mask 2 12 is projected and exposed on a wafer (photosensitive substrate) 2 14 via a projection optical system 2 13.
  • the aperture stop 208 is arranged near the reflection surface side of the exit-side reflection fly-eye optical system 209 and determines the numerical aperture of illumination light on the mask 212. is there. In other words, by changing the aperture of the aperture stop 208, it is possible to provide an optimal numerical aperture of illumination light for various exposure patterns.
  • the reflective fly-eye optical systems 207 and 209 in the illumination optical apparatus have sufficient functions.
  • the elemental optical systems of the reflective fly-eye optical systems 207 and 209 must be arranged in at least four rows, preferably six or more rows, in the aperture of the aperture stop 208. . Therefore, when the variable range of the aperture of the aperture stop 208 is set wide to provide the optimal numerical aperture of the illumination light for various exposure patterns, when the aperture of the aperture stop 208 is the smallest, In this case, it is necessary to ensure a sufficient number of element optical systems constituting the exit-side reflection type fly-eye optical system 209.
  • FIG. 8A is a front view showing an arrangement in which the required number of element optical systems of the exit-side reflective briar-eye optical system 209 are arranged with the aperture of the aperture stop 208 minimized.
  • FIG. 8B shows an enlarged view of the aperture of the aperture stop 208 using the exit-side reflective fly-eye optical system 209 composed of the small-sized element optical system shown in FIG. 8A. It is a front view which shows a thing. As shown in FIG. 8B, an enormous number of element optical systems are arranged in the aperture of the aperture stop 208.
  • the light beam reflected by the exit-side reflection fly-eye optical system 209 Light so that it does not enter the reflective fly-eye optical system 207 on the incident side.
  • the reflectivity of an EUV reflective film coated on reflective optical members such as reflective fly-eye optical systems 207 and 209 used in an EUV projection exposure apparatus depends on the angle of incidence of incident light on the reflective surface. Except when the is vertical or almost horizontal, it is lower than when it is vertical or horizontal.
  • the distance between the entrance-side reflection type fly-eye optical system 207 and the exit-side reflection type fly-eye optical system 209 is determined by the outer diameter of the reflection type fly-eye optical system 207, 209. It needs to be long enough.
  • the aperture of the aperture stop 208 in order to increase the distance between the entrance-side reflection fly-eye optical system 207 and the exit-side reflection fly-eye optical system 209 without changing the exposure range, the aperture of the aperture stop 208 must be increased. It is necessary to increase the focal length of the element optical systems by minimizing the number of element optical systems in the unit.
  • the aperture stop 208 To widen the variable range of the aperture of the aperture stop 208 to accommodate the optimal numerical aperture of illumination light for various exposure patterns, adjust the aperture of the aperture stop 208 to the minimum state. Therefore, it is necessary to reduce the size of the element optical systems of the reflection type fly-eye optical systems 207 and 209 and increase the number of element optical systems.
  • the reflective fly-eye optical system is designed so that the light flux does not enter the reflective fly-eye optical systems 207 and 209 at an incident angle of around 45 °. It is necessary to increase the focal length of the element optical systems 207 and 209 and reduce the number of the element optical systems.
  • An object of the present invention is to provide an illumination optical device capable of supplying optimal illumination light to a mask when EUV light is used as illumination light, a projection exposure device using the illumination optical device, and the projection exposure device. It is to provide an exposure method. Disclosure of the invention
  • the illumination optical device of the present invention is an illumination optical device for illuminating a mask using extreme ultraviolet light as illumination light, and has a reflection type having a plurality of element optical systems arranged in parallel: An optical system, a replacement reflective fly-eye optical system having a plurality of element optical systems arranged in parallel, and a fly-eye optical system for exchanging the reflective fly-eye optical system and the replaceable reflective fly-eye optical system An element optical system of the reflection type fly-eye optical system having a different focal length from an element optical system of the replacement reflection type fly-eye optical system; and an element optical system of the reflection type fly-eye optical system.
  • the ratio between the effective diameter and the focal length of the incident optical surface of the system and the ratio between the effective diameter and the focal length of the incident optical surface of the element optical system of the replacement reflective fly-eye optical system are constant.
  • the fly-eye optical system exchange unit may be configured to replace the reflective fly-eye optical system and an optical component located in front of the reflective fly-eye optical system with the replacement reflective fly-eye optical system. It is characterized in that the optical system is replaced with a replacement optical member located at a stage preceding the system and the replacement reflective fly-eye optical system.
  • the reflection type fly-eye optical system for replacement is provided, and the reflection type fly-eye optical system of the illumination optical device can be appropriately replaced. Therefore, it is possible to provide an illumination optical device including a reflective fly-eye optical system having an optimum numerical aperture of illumination light for a mask pattern.
  • the illumination optical device of the present invention is an illumination optical device for illuminating a mask using extreme ultraviolet light as illumination light, wherein: a reflective fly-eye optical system having a plurality of element optical systems arranged in parallel; A condenser optical system disposed between the mold fly-eye optical system and the mask, wherein the focal length of the condenser optical system is F con, and the longest width of the exposure range on the mask is w m, F con > 8 wm.
  • the focal length of the condenser optical system when the focal length of the condenser optical system is F ⁇ on and the longest width of the exposure range on the mask is wm, the condition of F con> 8 wm is satisfied. If the focal length is set sufficiently long, the light beam can be prevented from entering the reflective fly-eye optical system at an extremely oblique angle, so that the high reflectance of the reflective film coated on the fly-eye optical system is maintained. can do.
  • the projection exposure apparatus of the present invention includes an illumination optical device of the present invention and a mask pattern.
  • the reflection type fly-eye optical system of the illumination optical apparatus can be appropriately replaced by a replacement reflection-type fly-eye optical system. Therefore, a projection type exposure apparatus having a high resolution and sufficient exposure light intensity can be provided because a reflective fly-eye optical system having an optimum number of apertures of illumination light for a mask pattern can be installed and exposed. You can do it.
  • the exposure method of the present invention is the exposure method using the projection exposure apparatus of the present invention, wherein: an illumination step of illuminating the mask by the illumination optical device; and a pattern of the mask by the reflective projection optical system. Projecting an image onto the photosensitive substrate.
  • a projection exposure apparatus equipped with the illumination optical device of the present invention is used, and the illumination optical device has an optimal numerical aperture of illumination light for the exposure pattern. Exposure can be performed favorably.
  • FIG. 1 is a configuration diagram of a projection exposure apparatus according to an embodiment of the present invention.
  • FIG. 2A is a front view showing the configuration of the incident-side reflection fly-eye optical system according to the embodiment of the present invention.
  • FIG. 2B is a front view showing the configuration of the exit-side reflection fly-eye optical system according to the embodiment of the present invention.
  • FIG. 3A is a diagram for explaining the lateral width of the element optical system of the reflective fly-eye optical system according to the embodiment of the present invention.
  • FIG. 3B is a diagram for explaining the width of the illumination range of the mask according to the embodiment of the present invention.
  • FIG. 4A is a view showing an exit-side reflection type flag passing through an aperture stop according to the embodiment of the present invention.
  • FIG. 3 is a front view showing an eye optical system.
  • FIG. 4B is a front view showing a replacement exit-side reflection fly-eye optical system through a replacement aperture stop according to the embodiment of the present invention.
  • FIG. 5 is a flowchart for explaining the method for manufacturing the microphone port device according to the embodiment of the present invention.
  • FIG. 6 is a flowchart for explaining a microdevice manufacturing method according to the embodiment of the present invention.
  • FIG. 7 is a configuration diagram of a conventional projection exposure apparatus.
  • FIG. 8A is a front view showing a conventional exit-side reflection fly-eye optical system through an aperture stop. .
  • FIG. 8B is a front view showing a conventional exit-side reflection fly-eye optical system through another aperture stop.
  • FIG. 1 is a diagram showing a schematic configuration of a projection exposure apparatus according to an embodiment of the present invention.
  • This projection exposure apparatus is provided with a light source 2 for emitting exposure light having a wavelength of about 5 to 40 nm.
  • This light source 2 is obtained by condensing a laser beam emitted from a YAG (yttrium alminum garnet) laser light source 4 by a condensing optical system 6 and irradiating it with a high-concentration gas target supplied from a nozzle 8.
  • EUV extreme ultra violet
  • the luminous flux reflected by the condensing optical system 14 and converted to be approximately parallel enters the incident-side reflection type fly-eye optical system 16 in which a plurality of element optical systems, which are concave mirrors, are arranged in parallel.
  • the light beam incident on the incident-side reflective fly-eye optical system 16 is The light is reflected by the eye optical system 16, and enters, via the aperture stop 18, the exit-side reflective fly-eye optical system 20 in which a plurality of element optical systems, which are concave mirrors, are arranged in parallel.
  • the light beam incident on the exit-side reflective fly-eye optical system 20 is reflected by the exit-side reflective fly-eye optical system 20 and enters the mirror 22 via the aperture stop 18.
  • the light beam entering the mirror 22 is reflected by the mirror 22, enters the condenser mirror (condenser optical system) 24, is reflected by the condenser mirror 24, and is condensed on the mask 26.
  • the aperture stop 18 determines the numerical aperture of the illumination light, and the mirror 22 is a plane mirror for changing the traveling direction of the light beam.
  • FIG. 2A is a front view showing the incident-side reflective fly-eye optical system 16
  • FIG. 2B is a front view showing the exit-side reflective fly-eye optical system 20.
  • the element optical systems 16a of the entrance-side fly-eye optical system 16 and the element optical systems 20a of the exit-side reflective fly-eye optical system 20 are arranged in a one-to-one correspondence. And have the same focal length.
  • the light beam incident on the incident side reflection type fly-eye optical system 16 is wavefront divided by each element optical system 16 a of the incident side reflection type fly-eye optical system 16.
  • Each element optical system 20a of the system 20 receives each of the wavefront-divided individual light beams one by one.
  • the exit-side reflective fly-eye optical system 16 The optical system 20 serves as a surface light source in the Koehler illumination.
  • the luminous flux that is split by the wavefront by the reflection type fly-eye optical systems 16 and 20 and superimposed on the mask 26 can realize high illuminance uniformity on the mask 26.
  • the reflectance of the EUV reflective film coated on the reflective fly's eye optical system 16 and 20 is measured except when the incident angle of the incident light on the reflective surface is vertical or almost horizontal. Is reduced as compared to the case where it is vertical or horizontal. In particular, when the incident angle is around 45 °, the reflectivity decreases extremely. .Reflective fly-eye optical system 1
  • the distance between the entrance-side reflection fly-eye optical system 16 and the exit-side reflection fly-eye optical system 20 should be set to the respective reflection type. It must be sufficiently long for the outer diameter of the fly-eye optical system 16, 20. That is, if the diameter of the aperture of the aperture stop 18 is D and the focal length of the reflection type fly-eye optical systems 16 and 20 is F f 1 y, it is desirable that the condition of Expression 1 is satisfied.
  • the entrance-side reflection type Assuming that the width of the element optical system 16a constituting the fly-eye optical system 16 is wf (see FIG. 3A), it is desirable that the condition of Expression 2 is satisfied.
  • the focal length of the condenser mirror 24 must be sufficiently long so as to satisfy Equation 4. There is a need to.
  • a predetermined circuit pattern is formed on the surface of the mask 26, and the mask 26 is held on a mask stage (not shown) that can move two-dimensionally along a horizontal plane.
  • the light beam reflected by the mask 26 is reflected by the reflective projection optical system 2.
  • An image is formed on the photosensitive substrate 30 to which the resist has been applied through 8. Then, the pattern image of the arc-shaped mask 26 is projected and transferred onto the photosensitive substrate 30.
  • the light-sensitive substrate 30 is held on a substrate stage (not shown) that can move two-dimensionally along a horizontal plane.
  • the fly-eye set A containing the reflective fly-eye optical system 20 is a replacement condensing optical system (replacement optical system) located in front of the reflective fly-eye optical system 1 16, 120.
  • Components) 1 1 4 Replacement fly-eye optical system that stores replacement entrance-side reflective fly-eye optical system 1 16, replacement aperture stop 1 1 8 and replacement exit-side reflective fly-eye optical system 1 2 0 It is configured to be interchangeable with 1, B.
  • the fly eye set A and the replacement fly eye set B are held on a fly eye set stage (not shown) that can move two-dimensionally along a horizontal plane.
  • the control unit 32 reads the optimal numerical aperture of the illumination light in the pattern of the changed mask 26 stored in advance and replaces it. 3 Send the control signal to 4.
  • the switching device 34 moves the fly-eye set stage based on the control signal transmitted from the control section 32 to set up a fly-eye set having an optimal illumination light numerical aperture.
  • FIG. 4A and 4B are front views showing the exit-side reflection type fly-eye optical system through an aperture stop.
  • FIG. 4A is a front view showing an exit-side reflection type fly-eye optical system 20 through an aperture stop 18 in the fly-eye set A.
  • FIG. 4B is a front view showing the replacement exit-side reflection type fly-eye optical system i 20 through the replacement aperture stop 118 in the replacement fly eye set B.
  • Eye optics 20 is small in size It is composed of element optical systems.
  • the focal length of the element optical system of the exit-side reflection type fly-eye optical system 20 is small.
  • the effective diameter of the entrance optical surface of the replacement exit-side reflection fly-eye optical system 120 is large, that is, when the aperture diameter of the replacement aperture stop 1 18 is large.
  • the replacement emission-side reflection fly-eye optical system 120 is composed of a large-size element optical system. In other words, the focal length of the elemental optical system of the replacement exit-side reflection type fly-eye optical system 120 is large.
  • the ratio between the effective diameter of the entrance optical surface of the elemental optical system of the fly-eye set A in the fly-eye set A 20 and the focal length, and the replacement exit-side reflection in the replacement fly-eye set B The ratio between the effective diameter of the incident optical surface and the focal length of the element optical system of the type fly-eye optical system 120 is constant.
  • a “minimum number” of element optical systems is required. The “minimum number” varies depending on the specifications of the device and the intensity distribution of the light beam incident on the fly-eye optical system.
  • the illumination system of a semiconductor pattern optical device at least four rows within the diameter of the illumination aperture stop As described above, it is necessary to arrange the element optical systems in at least six rows.
  • FIG. 8A shows a view in which the exit-side reflection type fly-eye optical system 209 whose element optical system is sized in accordance with the decrease in the aperture is observed through the aperture stop 208.
  • FIG. 8B shows a diagram when the aperture of the aperture stop 208 is switched to a large aperture.
  • FIG. 8B is an example in which the huge number of element optical systems described above are arranged.
  • the distance between the entrance-side reflection fly-eye optical system and the exit-side reflection fly-eye optical system be sufficiently large for the respective outer diameters. This is because if the distance is small relative to the outer diameter, the light beam must enter the fly-eye optical system at an extremely oblique angle to separate the light beam going back and forth. Reflective films for EUV have extremely high reflectivity unless the incident light is vertical or almost horizontal to the reflective surface. Therefore, the incident angle near 45 ° must be avoided as much as possible.
  • the number of element optical systems must be reduced as much as possible. This is because the focal length of each element optical system must be short so that the exposure range does not change even if each element optical system becomes small. As described above, since each element optical system of the incident-side reflection fly-eye optical system is conjugate to the mask surface, if the focal length of each element optical system becomes shorter, the incident-side reflection fly-eye optical system becomes The distance between the system and the exit-side reflection fly-eye optical system must be reduced.
  • the projection exposure apparatus has a fly eye set and one replacement fly eye set.
  • two or more replacement fly eye sets may be provided.
  • a plurality of fly eye sets are held on a fly eye set stage rotatable along a horizontal plane, and the fly eye sets are held.
  • One of the fly eye sets is set by rotating the set stage.
  • the fly-eye set A is replaced with a replacement fly-eye set B.
  • the reflective fly-eye optical systems 16 and 20 and the aperture stop 18 that do not include the focusing optical system 14 are The reflection type fly-eye optical systems 1 16 and 120 which do not include the condensing optical system 114 and the aperture stop 1 18 may be replaced.
  • a reflection type fly-eye optical system for replacement is provided, and the reflection type fly-eye optical system of the illumination optical device can be appropriately replaced. Therefore, the projection exposure can be performed using an illumination optical device having a reflective fly-eye optical system having an optimal numerical aperture of the illumination light for the mask pattern. Even in this case, it is possible to maintain a high reflectance of the reflection film coated on the fly-eye optical system, and to provide a projection exposure apparatus having high resolution and sufficient exposure light intensity.
  • the mask is illuminated by the EUV illumination optical device (illumination step), and the pattern image formed on the mask is projected onto the photosensitive substrate using the reflective projection optical system.
  • a micro device semiconductor element, imaging element, liquid crystal display element, thin film magnetic head, etc.
  • FIG. 1 This will be described with reference to the flowchart of FIG.
  • step S301 of FIG. 5 a metal film is deposited on one lot of wafers.
  • step S302 a photoresist is applied on the metal film on the wafer of the one lot.
  • an appropriate fly-eye set is installed so as to provide an optimum numerical aperture of illumination light for each pattern on the mask, and in step S303, the mask is set using the projection exposure apparatus according to this embodiment.
  • the pattern image above is sequentially passed through the reflective projection optical system to each shot area on that one lot wafer. It is projected and exposed.
  • step S304 the photoresist on the one lot wafer is developed, and then in step S305, etching is performed on the one lot wafer using the resist pattern as a mask.
  • a circuit pattern corresponding to the pattern on the mask is formed in each shot area on each wafer.
  • steps S301 to S305 a metal is vapor-deposited on the wafer, a resist is applied on the metal film, and the respective steps of exposure, development, and etching are performed. It is needless to say that prior to the process, after a silicon oxide film is formed on the wafer, a resist is applied on the silicon oxide film, and each process such as exposure, development, and etching may be performed.
  • a liquid crystal display element as a micro device can be obtained by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate).
  • a predetermined pattern circuit pattern, electrode pattern, etc.
  • an appropriate fly-eye set is installed so that an optimal numerical aperture of illumination light is obtained for each mask pattern.
  • a so-called photolithography step of transferring and exposing the pattern of the mask onto a photosensitive substrate (a glass substrate coated with a resist) is performed.
  • a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. Thereafter, the exposed substrate is subjected to a development process, an etching process, a resist stripping process, and other processes to form a predetermined pattern on the substrate, and the process proceeds to a next color filter forming process S402.
  • a large number of sets of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix, or R,
  • a color filter is formed by arranging a plurality of sets of three stripe filters of G and B in the horizontal scanning line direction.
  • a cell assembling step S403 is performed.
  • the liquid crystal panel is formed using the substrate having the predetermined pattern obtained in the pattern forming step S401, the color filter obtained in the color filter forming step S402, and the like. (Liquid crystal cell).
  • a liquid crystal is interposed between the substrate having the predetermined pattern obtained in the pattern forming step S 401 and the color filter obtained in the color filter forming step S 402.
  • a liquid crystal panel liquid crystal cell
  • a module assembling step S404 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.
  • 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.
  • the “effective diameter of the entrance optical surface of the elemental optical system of the reflective fly-eye optical system” described in this specification is the elementary optical element shown in FIGS. 3A and 3B of the above embodiment.
  • the width of the system is called Wm or Wf
  • the width in the direction perpendicular to Wm or Wf or the width in the oblique direction may be called the effective diameter.
  • the reflection type fly-eye optical system for replacement is provided, and the reflection type fly-eye optical system of an illumination optical device can be replaced suitably. Therefore, it is possible to provide an illumination optical device having a reflective fly-eye optical system having an optimum numerical aperture of illumination light for a mask pattern.
  • the illumination optical device of the present invention since the illumination optical device of the present invention is provided, a replacement reflective fly-eye optical system is provided, and the reflective fly-eye optical system of the illumination optical device is appropriately replaced. be able to. Accordingly, since a reflective fly-eye optical system having an optimum numerical aperture of illumination light for a mask pattern can be installed and exposed for projection, a projection exposure apparatus having high resolution and sufficient exposure light intensity can be provided. Offer Can be
  • a projection exposure apparatus having the illumination optical device of the present invention is used, and the illumination optical device has an optimum numerical aperture of illumination light for an exposure pattern. Exposure of a fine exposure pattern can be favorably performed.
  • the illumination optical device of the present invention includes a semiconductor device, an image sensor, a liquid crystal display device, a thin-film magnetic head, and the like. Suitable for use in the manufacture of devices.

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  • General Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Optical Elements Other Than Lenses (AREA)
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  • Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)

Abstract

An illuminating optical device for illuminating a mask (26) using an extreme ultraviolet ray as an illuminating light, comprising reflection type fly-eye optical systems (16, 20) having a plurality of element optical systems arranged in parallel, interchanging reflection type fly-eye optical systems (116, 120) having a plurality of element optical systems arranged in parallel, and a fly-eye optical interchanging means for interchanging the reflection type fly-eye optical systems (16, 20) with the interchanging reflection type fly-eye optical systems (116, 120), wherein the element optical systems of the reflection type fly-eye optical systems (16, 20) have a focal distance different from that of the element optical systems of the interchanging reflection type fly-eye optical systems (116, 120), and a ratio between the effective diameter and the focal distance of the incident optical surface of the element optical systems of the reflection type fly-eye optical systems (16, 20) and a ratio between the effective diameter and the focal distance of the incident optical surface of the element optical systems of the interchanging reflection type fly-eye optical systems (116, 120) are kept constant.

Description

明 細 書 照明光学装置、 投影露光装置及び露光方法 技術分野  Description Illumination optical device, projection exposure apparatus and exposure method
この発明は、 半導体集積回路の製造等に用いられる照明光学装置、 該照明光学 装置を用いた投影露光装置及び該投影露光装置を用いた露光方法に関するもの である。 背景技術  The present invention relates to an illumination optical device used for manufacturing a semiconductor integrated circuit and the like, a projection exposure apparatus using the illumination optical device, and an exposure method using the projection exposure device. Background art
近年、 EUV (extreme ultra violet, 極紫外) と呼ばれる波長約 5〜 40 n m の領域の露光光を用いてマスクのパターン像を感光性基板上に投影露光する投 影露光装置の実用化が進められている。 EUVL (極紫外リソグラフィー） 用照 明光学装置には、 EUV光が透過屈折部材 （ガラス、 透過性結晶等） を透過しな いため、 反射光学部材が使用される。 EUVL用照明光学装置として、 反射型フ ライアイ光学系を用いた照明光学装置が提案されている (例えば、 特開平 1 1 - 312638号公報参照）。  In recent years, practical use of a projection exposure apparatus for projecting and exposing a mask pattern image onto a photosensitive substrate using exposure light having a wavelength of about 5 to 40 nm called EUV (extreme ultra violet) has been promoted. ing. In EUVL (extreme ultraviolet lithography) illuminating optics, reflective optics are used because EUV light does not pass through transmissive refraction members (glass, transmissive crystals, etc.). As an illumination optical device for EUVL, an illumination optical device using a reflective fly-eye optical system has been proposed (for example, see Japanese Patent Application Laid-Open No. 11-312638).
特開平 1 1一 312638号公報に記載されている照明光学装置によれば、 図 7に示すように、非 EUV光レーザ光源 201より射出して集光光学系 202に より集光された光束をノズル 203より供給されるターゲット物質に当てるこ とにより EUV光源 204が得られる。 EUV光源 204より発した EUV光は、 集光鏡 205により集光され、 引き回し光学系 206により反射されて、 凹面鏡 が多数並列に配列された光学素子である入射側反射型フライアイ光学系 207 に入射する。 次に、 入射側反射型フライアイ光学系 207にて波面分割された多 数の光束は、 可変可能な開口部を有する開口絞り 208を介して、 凹面鏡が多数 並列に配列された光学素子である射出側反射型フライアイ光学系 209により 反射され、 再ぴ開口絞り 208を介して、 ミラー 210に入射する。 ミラー 21 0で反射された光束は、光学系 2 1 1により集光され、マスク 2 1 2を照射する。 照射されたマスク 2 1 2のパターン像は、投影光学系 2 1 3を介して'、ウェハ（感 光性基板） 2 1 4に投影露光される。 According to the illumination optical device described in Japanese Patent Application Laid-Open No. H11-312638, as shown in FIG. 7, a light beam emitted from a non-EUV light laser light source 201 and condensed by a condensing optical system 202 is emitted. EUV light source 204 is obtained by hitting the target material supplied from nozzle 203. The EUV light emitted from the EUV light source 204 is condensed by a condenser mirror 205, reflected by a guiding optical system 206, and then transmitted to an entrance-side reflective fly-eye optical system 207, which is an optical element in which a number of concave mirrors are arranged in parallel. Incident. Next, a large number of light beams split by the wavefront in the incident-side reflection type fly-eye optical system 207 are an optical element in which a large number of concave mirrors are arranged in parallel via an aperture stop 208 having a variable opening. The light is reflected by the exit-side reflection fly-eye optical system 209, and enters the mirror 210 via the re-aperture stop 208. Mirror 21 The light beam reflected at 0 is converged by the optical system 211 and irradiates the mask 212. The illuminated pattern image of the mask 2 12 is projected and exposed on a wafer (photosensitive substrate) 2 14 via a projection optical system 2 13.
なお、 開口絞り 2 0 8は、 射出側反射型フライアイ光学系 2 0 9の反射面側近 傍に配置されており、 マスク 2 1 2上での照明光の開口数を決定するためのもの である。 即ち、 開口絞り 2 0 8の開口部を変化させることにより、 さまざまな露 光パターンに最適な照明光の開口数を提供する。  The aperture stop 208 is arranged near the reflection surface side of the exit-side reflection fly-eye optical system 209 and determines the numerical aperture of illumination light on the mask 212. is there. In other words, by changing the aperture of the aperture stop 208, it is possible to provide an optimal numerical aperture of illumination light for various exposure patterns.
ところで、 特開平 1 1一 3 1 2 6 3 8号公報に記載されている投影露光装置に おいて、 照明光学装置内の反射型フライアイ光学系 2 0 7 , 2 0 9がその機能を 十分に発揮するためには、 反射型フライアイ光学系 2 0 7 , 2 0 9の要素光学系 が開口絞り 2 0 8の開口部内に少なくとも 4列以上、望ましくは 6列以上配列さ れる必要がある。 従って、 さまざまな露光パターンに最適な照明光の開口数を提 供するために開口絞り 2 0 8の開口部の可変範囲を広く設定した場合には、 開口 絞り 2 0 8の開口部が最小の時においても射出側反射型フライアイ光学系 2 0 9を構成する要素光学系の数を十分に確保する必要がある。  By the way, in the projection exposure apparatus described in Japanese Patent Application Laid-Open No. H11-131-2638, the reflective fly-eye optical systems 207 and 209 in the illumination optical apparatus have sufficient functions. In order to achieve the best performance, the elemental optical systems of the reflective fly-eye optical systems 207 and 209 must be arranged in at least four rows, preferably six or more rows, in the aperture of the aperture stop 208. . Therefore, when the variable range of the aperture of the aperture stop 208 is set wide to provide the optimal numerical aperture of the illumination light for various exposure patterns, when the aperture of the aperture stop 208 is the smallest, In this case, it is necessary to ensure a sufficient number of element optical systems constituting the exit-side reflection type fly-eye optical system 209.
ここで、 図 8 Aは、 開口絞り 2 0 8の開口部を最小にして、 射出側反射型ブラ ィアイ光学系 2 0 9の要素光学系を必要数だけ配列させたものを示す正面図で ある。 図 8 Aに示すように、 開口絞り 2 0 8の開口部を最小にした状態で射出側 反射型フライアイ光学系 2 0 9の要素光学系を必要数だけ配列させるためには、 要素光学系のサイズを小さくする必要がある。 また、 図 8 Bは、 図 8 Aに示すサ ィズの小さい要素光学系により構成された射出側反射型フライアイ光学系 2 0 9を用いて、 開口絞り 2 0 8の開口部を大きくしたものを示す正面図である。 図 8 Bに示すように、 開口絞り 2 0 8の開口部内に莫大な数の要素光学系が配列さ れることになる。  Here, FIG. 8A is a front view showing an arrangement in which the required number of element optical systems of the exit-side reflective briar-eye optical system 209 are arranged with the aperture of the aperture stop 208 minimized. . As shown in FIG. 8A, in order to arrange the required number of element optical systems of the exit-side reflective fly-eye optical system 209 with the aperture of the aperture stop 208 minimized, the element optical system Needs to be reduced in size. FIG. 8B shows an enlarged view of the aperture of the aperture stop 208 using the exit-side reflective fly-eye optical system 209 composed of the small-sized element optical system shown in FIG. 8A. It is a front view which shows a thing. As shown in FIG. 8B, an enormous number of element optical systems are arranged in the aperture of the aperture stop 208.
' また、入射側反射型フライアイ光学系 2 0 7と射出側反射型フライアイ光学系 2 0 9との間隔が短い場合に、射出側反射型フライアイ光学系 2 0 9により反射 された光束を入射側反射型フライアイ光学系 2 0 7に入射しないように射出さ せるために、 光束を極度に斜めから射出側反射型フライアイ光学系 2 0 9に入射 させる必要がある。 しかしながら、 E U V用投影露光装置に用いられる反射型フ ライアイ光学系 2 0 7 , 2 0 9等の反射光学部材に被覆される E U V用反射膜の 反射率は、 その反射面に対する入射光の入射角度が垂直であるか又はほとんど水 平である場合以外については、 垂直又は水平である場合に比較して低下する。 特 に、 入射角度が 4 5 ° 近傍では極度に反射率が低下する。 従って、 入射側反射型 フライアイ光学系 2 0 7と射出側反射型フライアイ光学系 2 0 9との間隔は、 反 射型フライアイ光学系 2 0 7 , 2 0 9の外径に対して十分に長くする必要がある。 ここで、 露光範囲を変化させることなく入射側反射型フライアイ光学系 2 0 7と 射出側反射型フライアイ光学系 2 0 9との間隔を長くするためには、 開口絞り 2 0 8の開口部内の要素光学系の数を極力減少させることにより要素光学系の焦 点距離を長くする必要がある。 ′ Also, when the distance between the incident-side reflection fly-eye optical system 209 and the exit-side reflection fly-eye optical system 209 is short, the light beam reflected by the exit-side reflection fly-eye optical system 209 Light so that it does not enter the reflective fly-eye optical system 207 on the incident side. In order to make this possible, it is necessary for the light beam to enter the exit-side reflection type fly-eye optical system 209 from an extremely oblique angle. However, the reflectivity of an EUV reflective film coated on reflective optical members such as reflective fly-eye optical systems 207 and 209 used in an EUV projection exposure apparatus depends on the angle of incidence of incident light on the reflective surface. Except when the is vertical or almost horizontal, it is lower than when it is vertical or horizontal. In particular, when the incident angle is around 45 °, the reflectivity decreases extremely. Therefore, the distance between the entrance-side reflection type fly-eye optical system 207 and the exit-side reflection type fly-eye optical system 209 is determined by the outer diameter of the reflection type fly-eye optical system 207, 209. It needs to be long enough. Here, in order to increase the distance between the entrance-side reflection fly-eye optical system 207 and the exit-side reflection fly-eye optical system 209 without changing the exposure range, the aperture of the aperture stop 208 must be increased. It is necessary to increase the focal length of the element optical systems by minimizing the number of element optical systems in the unit.
さまざまな露光パターンに最適な照明光の開口数に対応するために開口絞り 2 0 8の開口部の可変範囲を広く設定するためには、 開口絞り 2 0 8の開口部が 最小の状態に合わせて反射型フライアイ光学系 2 0 7 , 2 0 9の要素光学系のサ ィズを小さくし、 要素光学系の数を増加させる必要がある。 一方、 E U V用反射 膜の高反射率を維持するためには、 光束が反射型フライアイ光学系 2 0 7 , 2 0 9に入射角度 4 5 ° 近傍で入射しないように反射型フライアイ光学系 2 0 7 , 2 0 9の要素光学系の焦点距離を長くし、 その要素光学系の数を減少させる必要が ある。  To widen the variable range of the aperture of the aperture stop 208 to accommodate the optimal numerical aperture of illumination light for various exposure patterns, adjust the aperture of the aperture stop 208 to the minimum state. Therefore, it is necessary to reduce the size of the element optical systems of the reflection type fly-eye optical systems 207 and 209 and increase the number of element optical systems. On the other hand, in order to maintain the high reflectivity of the reflective film for EUV, the reflective fly-eye optical system is designed so that the light flux does not enter the reflective fly-eye optical systems 207 and 209 at an incident angle of around 45 °. It is necessary to increase the focal length of the element optical systems 207 and 209 and reduce the number of the element optical systems.
この発明の課題は、 E U V光を照明光とした場合に、 マスクに最適な照明光を 供給することができる照明光学装置、 該照明光学装置を用いた投影露光装置及び 該投影露光装置を用いた露光方法を提供することである。 発明の開示  An object of the present invention is to provide an illumination optical device capable of supplying optimal illumination light to a mask when EUV light is used as illumination light, a projection exposure device using the illumination optical device, and the projection exposure device. It is to provide an exposure method. Disclosure of the invention
この発明の照明光学装置は、 極紫外光を照明光としてマスクを照明する照明光 学装置であって、 並列に配列された複数の要素光学系を有する反射型： 光学系と、 並列に配列された複数の要素光学系を有する交換用反射型フライアイ 光学系と、 前記反射型フライアイ光学系と前記交換用反射型フライアイ光学系を 交換するフライアイ光学系交換手段とを備え、 前記反射型フライアイ光学系の要 素光学系は前記交換用反射型フライアイ光学系の要素光学系と異なる焦点距離 を有し、 前記反射型フライアイ光学系の要素光学系の入射光学面の有効径と焦点 距離の比率と、 前記交換用反射型フライアイ光学系の要素光学系の入射光学面の 有効径と焦点距離の比率が一定であることを特徴とする。 The illumination optical device of the present invention is an illumination optical device for illuminating a mask using extreme ultraviolet light as illumination light, and has a reflection type having a plurality of element optical systems arranged in parallel: An optical system, a replacement reflective fly-eye optical system having a plurality of element optical systems arranged in parallel, and a fly-eye optical system for exchanging the reflective fly-eye optical system and the replaceable reflective fly-eye optical system An element optical system of the reflection type fly-eye optical system having a different focal length from an element optical system of the replacement reflection type fly-eye optical system; and an element optical system of the reflection type fly-eye optical system. The ratio between the effective diameter and the focal length of the incident optical surface of the system and the ratio between the effective diameter and the focal length of the incident optical surface of the element optical system of the replacement reflective fly-eye optical system are constant.
また、 この発明の照明光学装置は、 前記フライアイ光学系交換手段が前記反射 型フライアイ光学系及び前記反射型フライアイ光学系の前段に位置する光学部 材を前記交換用反射型フライアイ光学系及び前記交換用反射型フライアイ光学 系の前段に位置する交換用光学部材に交換することを特徴とする。  Further, in the illumination optical apparatus according to the present invention, the fly-eye optical system exchange unit may be configured to replace the reflective fly-eye optical system and an optical component located in front of the reflective fly-eye optical system with the replacement reflective fly-eye optical system. It is characterized in that the optical system is replaced with a replacement optical member located at a stage preceding the system and the replacement reflective fly-eye optical system.
この照明光学装置によれば、 交換用反射型フライアイ光学系を備えており照明 光学装置の反射型フライアイ光学系を適宜交換することができる。 従って、 マス クのパターンに最適な照明光の開口数を有している反射型フライアイ光学系を 備えた照明光学装置を提供することができる。  According to this illumination optical device, the reflection type fly-eye optical system for replacement is provided, and the reflection type fly-eye optical system of the illumination optical device can be appropriately replaced. Therefore, it is possible to provide an illumination optical device including a reflective fly-eye optical system having an optimum numerical aperture of illumination light for a mask pattern.
また、 この発明の照明光学装置は、 極紫外光を照明光としてマスクを照明する 照明光学装置であって、 並列に配列された複数の要素光学系を有する反射型フラ ィアイ光学系と、 前記反射型フライアイ光学系と前記マスクとの間に配置された コンデンサー光学系とを備え、 前記コンデンサー光学系の焦点距離を F c o n , 前記マスク上の露光範囲の最長横幅を wmとするとき、 F c o n〉8 wmの条件 を満足することを特徴とする。  Further, the illumination optical device of the present invention is an illumination optical device for illuminating a mask using extreme ultraviolet light as illumination light, wherein: a reflective fly-eye optical system having a plurality of element optical systems arranged in parallel; A condenser optical system disposed between the mold fly-eye optical system and the mask, wherein the focal length of the condenser optical system is F con, and the longest width of the exposure range on the mask is w m, F con > 8 wm.
この照明光学装置によれば、 コンデンサー光学系の焦点距離を F ς o n、 マス ク上の露光範囲の最長横幅を wmとしたとき F c o n > 8 wmの条件を満足す るようにコンデンサー光学系の焦点距離を十分に長くした場合には、 光束が反射 型フライアイ光学系に極めて斜めに入射することを防ぐことができるため、 フラ ィアイ光学系に被覆されている反射膜の高反射率を維持することができる。  According to this illumination optical device, when the focal length of the condenser optical system is Fςon and the longest width of the exposure range on the mask is wm, the condition of F con> 8 wm is satisfied. If the focal length is set sufficiently long, the light beam can be prevented from entering the reflective fly-eye optical system at an extremely oblique angle, so that the high reflectance of the reflective film coated on the fly-eye optical system is maintained. can do.
また、 この発明の投影露光装置は、 この発明の照明光学装置と、 マスクのパタ 一ン像を感光性基板上に形成する反射型投影光学系とを備えることを特徴とす る。 Also, the projection exposure apparatus of the present invention includes an illumination optical device of the present invention and a mask pattern. A reflective projection optical system for forming an image on a photosensitive substrate.
この投影露光装置によれば、 この発明の照明光学装置を備えているため、 交換 用反射型フライアイ光学系を備えており照明光学装置の反射型フライアイ光学 系を適宜交換することができる。 従って、 マスクのパターンに最適な照明光の開 口数を有している反射型フライアイ光学系を設置し投影露光することができる ため、 高解像度及び十分な露光光強度を有する投影露光装置を提供することがで さる。  According to this projection exposure apparatus, since the illumination optical apparatus of the present invention is provided, the reflection type fly-eye optical system of the illumination optical apparatus can be appropriately replaced by a replacement reflection-type fly-eye optical system. Therefore, a projection type exposure apparatus having a high resolution and sufficient exposure light intensity can be provided because a reflective fly-eye optical system having an optimum number of apertures of illumination light for a mask pattern can be installed and exposed. You can do it.
また、 この発明の露光方法は、 この発明の投影露光装置を用いた露光方法にお いて、 前記照明光学装置により前記マスクを照明する照明工程と、 前記反射型投 影光学系により前記マスクのパターン像を前記感光性基板上に投影する投影ェ 程とを含むことを特徴とする。  Further, the exposure method of the present invention is the exposure method using the projection exposure apparatus of the present invention, wherein: an illumination step of illuminating the mask by the illumination optical device; and a pattern of the mask by the reflective projection optical system. Projecting an image onto the photosensitive substrate.
この露光方法によれば、 この発明の照明光学装置を備えた投影露光装置を用い、 その照明光学装置が露光パターンに最適な照明光の開口数を有しているため、微 細な露光パターンの露光を良好に行うことができる。 図面の簡単な説明  According to this exposure method, a projection exposure apparatus equipped with the illumination optical device of the present invention is used, and the illumination optical device has an optimal numerical aperture of illumination light for the exposure pattern. Exposure can be performed favorably. BRIEF DESCRIPTION OF THE FIGURES
図 1は、 この発明の実施の形態にかかる投影露光装置の構成図である。  FIG. 1 is a configuration diagram of a projection exposure apparatus according to an embodiment of the present invention.
図 2 Aは、 この発明の実施の形態にかかる入射側反射型フライアイ光学系の構 成を示す正面図である。  FIG. 2A is a front view showing the configuration of the incident-side reflection fly-eye optical system according to the embodiment of the present invention.
図 2 Bは、 この発明の実施の形態にかかる射出側反射型フライアイ光学系の構 成を示す正面図である。  FIG. 2B is a front view showing the configuration of the exit-side reflection fly-eye optical system according to the embodiment of the present invention.
図 3 Aは、 この発明の実施の形態にかかる反射型フライアイ光学系の要素光学 系の横幅を説明するための図である。  FIG. 3A is a diagram for explaining the lateral width of the element optical system of the reflective fly-eye optical system according to the embodiment of the present invention.
図 3 Bは、 この発明の実施の形態にかかるマスクの照明範囲の横幅を説明する ための図である。  FIG. 3B is a diagram for explaining the width of the illumination range of the mask according to the embodiment of the present invention.
図 4 Aは、 この発明の実施の形態にかかる開口絞りを通した射出側反射型フラ ィアイ光学系を示す正面図である。 FIG. 4A is a view showing an exit-side reflection type flag passing through an aperture stop according to the embodiment of the present invention. FIG. 3 is a front view showing an eye optical system.
図 4 Bは、 この発明の実施の形態にかかる交換用開口絞りを通した交換用射出 側反射型フライアイ光学系を示す正面図である。  FIG. 4B is a front view showing a replacement exit-side reflection fly-eye optical system through a replacement aperture stop according to the embodiment of the present invention.
図 5は、 この発明の実施の形態にかかるマイク口デバイスの製造方法を説明す るためのフローチヤ一トである。  FIG. 5 is a flowchart for explaining the method for manufacturing the microphone port device according to the embodiment of the present invention.
図 6は、 この発明の実施の形態にかかるマイクロデバイスの製造方法を説明す るためのフローチャートである。  FIG. 6 is a flowchart for explaining a microdevice manufacturing method according to the embodiment of the present invention.
図 7は、 従来の投影露光装置の構成図である。  FIG. 7 is a configuration diagram of a conventional projection exposure apparatus.
図 8 Aは、従来の開口絞りを通した射出側反射型フライアイ光学系を示す正面 図である。 .  FIG. 8A is a front view showing a conventional exit-side reflection fly-eye optical system through an aperture stop. .
図 8 Bは、従来の別の開口絞りを通した射出側反射型フライアイ光学系を示す 正面図である。 発明を実施するための最良の形態  FIG. 8B is a front view showing a conventional exit-side reflection fly-eye optical system through another aperture stop. BEST MODE FOR CARRYING OUT THE INVENTION
以下、 図面を参照して、 この発明の実施の形態にかかる投影露光装置について 説明する。 図 1は、 この発明の実施の形態にかかる投影露光装置の概略構成を示 す図である。  Hereinafter, a projection exposure apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a projection exposure apparatus according to an embodiment of the present invention.
この投影露光装置には、約 5〜4 0 n mの波長の露光光を射出する光源 2が備 えら ている。 この光源 2は、 Y A G (yttrium alminum garnet) レ一ザ光源 4 から射出したレーザ光を集光光学系 6で集光し、 ノズル 8より供給される高濃度 のガスターゲットに当てることにより得られる点状の E U V (extreme ultra violet, 極紫外） 光源である。 なお、 E U V光源から射出する E U V波長の光は 大気を透過できないため、 装置全体は真空チャンバ 1 0に格納されている。 光源 2から射出した光束は、集光鏡 1 2により集光され集光光学系 1 4に入射 する。 集光光学系 1 4により反射され略平行に変換された光束は、 凹面鏡である 要素光学系が複数並列に配列された入射側反射型フラィアイ光学系 1 6に入射 する。 入射側反射型フライアイ光学系 1 6に入射した光束は、 入射側反射型フラ ィアイ光学系 1 6で反射され、 開口絞り 1 8を介して、 凹面鏡である要素光学系 が複数並列に配列された射出側反射型フライアイ光学系 2 0に入射する。 射出側 反射型フライアイ光学系 2 0に入射した光束は、射出側反射型フライアイ光学系 2 0で反射され、 開口絞り 1 8を介してミラー 2 2に入射する。 ミラー 2 2に入 射した光束は、 ミラー 2 2で反射され、 コンデンサーミラー （コンデンサー光学 系） 2 4に入射して、 コンデンサーミラー 2 4で反射され、 マスク 2 6上で集光 する。 なお、 開口絞り 1 8は照明光の開口数を決定するものであり、 ミラー 2 2 は光束の進行方向を変えるための平面鏡である。 This projection exposure apparatus is provided with a light source 2 for emitting exposure light having a wavelength of about 5 to 40 nm. This light source 2 is obtained by condensing a laser beam emitted from a YAG (yttrium alminum garnet) laser light source 4 by a condensing optical system 6 and irradiating it with a high-concentration gas target supplied from a nozzle 8. EUV (extreme ultra violet) light source. Since the EUV light emitted from the EUV light source cannot pass through the atmosphere, the entire apparatus is stored in the vacuum chamber 10. The light beam emitted from the light source 2 is condensed by the condenser mirror 12 and enters the condenser optical system 14. The luminous flux reflected by the condensing optical system 14 and converted to be approximately parallel enters the incident-side reflection type fly-eye optical system 16 in which a plurality of element optical systems, which are concave mirrors, are arranged in parallel. The light beam incident on the incident-side reflective fly-eye optical system 16 is The light is reflected by the eye optical system 16, and enters, via the aperture stop 18, the exit-side reflective fly-eye optical system 20 in which a plurality of element optical systems, which are concave mirrors, are arranged in parallel. The light beam incident on the exit-side reflective fly-eye optical system 20 is reflected by the exit-side reflective fly-eye optical system 20 and enters the mirror 22 via the aperture stop 18. The light beam entering the mirror 22 is reflected by the mirror 22, enters the condenser mirror (condenser optical system) 24, is reflected by the condenser mirror 24, and is condensed on the mask 26. The aperture stop 18 determines the numerical aperture of the illumination light, and the mirror 22 is a plane mirror for changing the traveling direction of the light beam.
図 2 Aは入射側反射型フライアイ光学系 1 6、 図 2 Bは射出側反射型フライァ ィ光学系 2 0を示す正面図である。 入射側フライアイ光学系 1 6のそれぞれの要 素光学系 1 6 a及び射出側反射型フライアイ光学系 2 0のそれぞれの要素光学 系 2 0 aは、 一対一に対応した状態でそれぞれ配列されており、 同一の焦点距離 を有している。 入射側反射型フライアイ光学系 1 6に入射した光束は、 入射側反 射型フライアイ光学系 1 6のそれぞれの要素光学系 1 6 aにより波面分割され- る。 入射側反射型フライアイ光学系 1 6により波面分割された多数の光束は、 開 口絞り 1 8を介して、 射出側反射型フライアイ光学系 2 0に入射し、 射出側反射 型フライアイ光学系 2 0のそれぞれの要素光学系 2 0 aは、波面分割された個々 の光束を 1本ずつ受ける。 ここで、 入射側反射型フライアイ光学系 1 6の要素光 学系 1 6 aとマスク 2 6上の被露光面とは共役となるように配置されているた め、 射出側反射型フライアイ光学系 2 0がケーラ一照明における面光源となる。 反射型フライアイ光学系 1 6 , 2 0により波面分割されて射出する光束は、 マス ク 2 6上で重畳することによりマスク 2 6上における高照度均一性を実現する ことができる。  FIG. 2A is a front view showing the incident-side reflective fly-eye optical system 16, and FIG. 2B is a front view showing the exit-side reflective fly-eye optical system 20. The element optical systems 16a of the entrance-side fly-eye optical system 16 and the element optical systems 20a of the exit-side reflective fly-eye optical system 20 are arranged in a one-to-one correspondence. And have the same focal length. The light beam incident on the incident side reflection type fly-eye optical system 16 is wavefront divided by each element optical system 16 a of the incident side reflection type fly-eye optical system 16. A large number of light beams split by the incident-side reflection type fly-eye optical system 16 enter the exit-side reflection type fly-eye optical system 20 via the aperture stop 18, and are emitted to the exit-side reflection type fly-eye optical system. Each element optical system 20a of the system 20 receives each of the wavefront-divided individual light beams one by one. Here, since the element optical system 16a of the incident-side reflective fly-eye optical system 16 and the surface to be exposed on the mask 26 are arranged to be conjugate with each other, the exit-side reflective fly-eye optical system 16 The optical system 20 serves as a surface light source in the Koehler illumination. The luminous flux that is split by the wavefront by the reflection type fly-eye optical systems 16 and 20 and superimposed on the mask 26 can realize high illuminance uniformity on the mask 26.
ここで、 反射型フライアイ光学系 1 6， 2 0に被覆される E U V用反射膜の反 射率は、 その反射面に対する入射光の入射角度が垂直であるか又はほとんど水平 である場合以外については、垂直又は水平である場合に比較して低下する。特に、 入射角度が 4 5 ° 近傍では極度に反射率は低下する。.反射型フライアイ光学系 1 6 , 2 0に光束が極めて斜め方向から入射しないようにするために、 入射側反射 型フライアイ光学系 1 6と射出側反射型フライアイ光学系 2 0との間隔をそれ ぞれの反射型フライアイ光学系 1 6 , 2 0の外径に対して十分に長くする必要が ある。 即ち、 開口絞り 1 8の開口部直径を D、 反射型フライアイ光学系 1 6 , 2 0の焦点距離を F f 1 yとすると、 数式 1の条件を満足することが望ましい。 Here, the reflectance of the EUV reflective film coated on the reflective fly's eye optical system 16 and 20 is measured except when the incident angle of the incident light on the reflective surface is vertical or almost horizontal. Is reduced as compared to the case where it is vertical or horizontal. In particular, when the incident angle is around 45 °, the reflectivity decreases extremely. .Reflective fly-eye optical system 1 In order to prevent the light flux from entering from the oblique direction to 6, 20, the distance between the entrance-side reflection fly-eye optical system 16 and the exit-side reflection fly-eye optical system 20 should be set to the respective reflection type. It must be sufficiently long for the outer diameter of the fly-eye optical system 16, 20. That is, if the diameter of the aperture of the aperture stop 18 is D and the focal length of the reflection type fly-eye optical systems 16 and 20 is F f 1 y, it is desirable that the condition of Expression 1 is satisfied.
(数式 1 )  (Formula 1)
D / F f l y < 0 . 5  D / F f l y <0.5. 5
また、 射出側反射型フライアイ光学系 2 0を構成する要素光学系 2 0 aは、 開 口絞り 1 8の開口部内に少なくとも 4列以上配列されることが望ましいことか ら、入射側反射型フライアイ光学系 1 6を構成する要素光学系 1 6 aの横幅を w f (図 3 A参照) とすると、 数式 2の条件を満足することが望ましい。  In addition, since it is desirable that at least four rows or more of the element optical systems 20a constituting the exit-side reflection type fly-eye optical system 20 be arranged in the opening of the aperture stop 18, the entrance-side reflection type Assuming that the width of the element optical system 16a constituting the fly-eye optical system 16 is wf (see FIG. 3A), it is desirable that the condition of Expression 2 is satisfied.
(数式 2 )  (Equation 2)
w f < D/ 4  w f <D / 4
ここで、 マスク 2 6の照明範囲の横幅を wm (図 3 B参照）、 コンデンサーミ ラー 2 4の焦点距離を F c o nとすると、 数式 3の関係が成り立つ。  Here, assuming that the width of the illumination range of the mask 26 is wm (see FIG. 3B) and the focal length of the condenser mirror 24 is F con, the relationship of Expression 3 is established.
(数式 3 ) (Equation 3)
Figure imgf000010_0001
Figure imgf000010_0001
更に、 数式 1に数式 3を代入し、 次に、 数式 2を代入すると、 数式 4の関係が 成り立つ。  Further, when Expression 3 is substituted into Expression 1, and then Expression 2 is substituted, the relationship of Expression 4 is established.
(数式 4 )  (Equation 4)
F c o 11 ク 8 wm  F c o 11 k 8 wm
従って、射出側反射型フライアイ光学系 2 0に入射光が極めて斜めに入射しな いようにするためには、 数式 4を満足するように、 コンデンサーミラー 2 4の焦 点距離を十分に長くする必要がある。  Therefore, in order to prevent the incident light from entering the exit-side reflection type fly-eye optical system 20 at an extremely oblique angle, the focal length of the condenser mirror 24 must be sufficiently long so as to satisfy Equation 4. There is a need to.
マスク 2 6の表面には、 所定の回路パターンが形成されており、 このマスク 2 6は、 水平平面内に沿って 2次元的に移動可能なマスクステージ （図示せず） に 保持されている。 このマスク 2 6により反射された光束は、 反射型投影光学系 2 8を介してレジストが塗布された感光性基板 3 0上に結像される。 そして感光性 基板 3 0上には、 円弧状のマスク 2 6のパターン像が投影転写される。 なお、 感 光性基板 3 0は、 水平平面内に沿って 2次元的に移動可能な基板ステージ （図示 せず） に保持されている。 マスクステージ及ぴ基板ステージを互いに反対方向へ 移動させることにより、 マスク 2 6上に形成されているパターン全体が反射型投 影光学系 2 8を介して感光性基板 3 0上に走查露光される。 A predetermined circuit pattern is formed on the surface of the mask 26, and the mask 26 is held on a mask stage (not shown) that can move two-dimensionally along a horizontal plane. The light beam reflected by the mask 26 is reflected by the reflective projection optical system 2. An image is formed on the photosensitive substrate 30 to which the resist has been applied through 8. Then, the pattern image of the arc-shaped mask 26 is projected and transferred onto the photosensitive substrate 30. The light-sensitive substrate 30 is held on a substrate stage (not shown) that can move two-dimensionally along a horizontal plane. By moving the mask stage and the substrate stage in directions opposite to each other, the entire pattern formed on the mask 26 is scanned and exposed on the photosensitive substrate 30 via the reflective projection optical system 28. You.
また、反射型フライアイ光学系 1 6 , 2 0の前段に位置している集光光学系（光 学部材） 1 4、 入射側反射型フライアイ光学系 1 6、 開口絞り 1 8及び射出側反 射型フライアイ光学系 2 0を格納しているフライアイセット Aは、反射型フライ アイ光学系 1 1 6 , 1 2 0の前段に位置している交換用集光光学系 (交換用光学 部材） 1 1 4、 交換用入射側反射型フライアイ光学系 1 1 6、 交換用開口絞り 1 1 8及び交換用射出側反射型フライアイ光学系 1 2 0を格納している交換用フ ライアイセッ 1、 Bと交換できるように構成されている。 フライアイセット A及ぴ 交換用フライアイセット Bは、水平平面内に沿って 2次元的に移動可能なフライ アイセットステージ (図示せず) に保持されている。 制御部 3 2は、 マスクステ ージに保持されるマスク 2 6が変更される際に、 予め記憶されている変更された マスク 2 6のそのパターンにおける最適な照明光の開口数を読み込み、 交換装置 3 4に制御信号を送信する。 交換装置 3 4は、 制御部 3 2より送信された制御信 号に基づいて、 フライアイセットステージを移動させることにより最適な照明光 の開口数を有するフライアイセットの設置を行なう。  In addition, the condensing optical system (optical member) 14 located in front of the reflective fly-eye optical systems 16 and 20, the incident-side reflective fly-eye optical system 16, the aperture stop 18 and the exit side The fly-eye set A containing the reflective fly-eye optical system 20 is a replacement condensing optical system (replacement optical system) located in front of the reflective fly-eye optical system 1 16, 120. Components) 1 1 4 Replacement fly-eye optical system that stores replacement entrance-side reflective fly-eye optical system 1 16, replacement aperture stop 1 1 8 and replacement exit-side reflective fly-eye optical system 1 2 0 It is configured to be interchangeable with 1, B. The fly eye set A and the replacement fly eye set B are held on a fly eye set stage (not shown) that can move two-dimensionally along a horizontal plane. When the mask 26 held in the mask stage is changed, the control unit 32 reads the optimal numerical aperture of the illumination light in the pattern of the changed mask 26 stored in advance and replaces it. 3 Send the control signal to 4. The switching device 34 moves the fly-eye set stage based on the control signal transmitted from the control section 32 to set up a fly-eye set having an optimal illumination light numerical aperture.
図 4 A及び図 4 Bは、 開口絞りを通した射出側反射型フライアイ光学系を示す 正面図である。 図 4 Aは、 フライアイセット Aにおける開口絞り 1 8を通した射 出側反射型フライアイ光学系 2 0を示す正面図である。 図 4 Bは、 交換用フライ アイセット Bにおける交換用開口絞り 1 1 8を通した交換用射出側反射型フラ ィアイ光学系 i 2 0を示す正面図である。 図 4 Aに示すように、 射出側反射型フ ライアイ光学系 2 0の入射光学面の有効径が小さい場合、 即ち、 開口絞り 1 8の 開口部直径が小さい場合には、射出側反射型フライアイ光学系 2 0はサイズの小 さい要素光学系で構成されている。 即ち、 射出側反射型フライアイ光学系 2 0の 要素光学系の焦点距離は小さくなつている。 一方、 図 4 Bに示すように、 交換用 射出側反射型フライアイ光学系 1 2 0の入射光学面の有効径が大きい場合、即ち、 交換用開口絞り 1 1 8の開口部直径が大きい場合には、 交換用射出側反射型フラ ィアイ光学系 1 2 0はサイズの大きい要素光学系で構成されている。 即ち、 交換 用射出側反射型フライアイ光学系 1 2 0の要素光学系の焦点距離は大きくなつ ている。 4A and 4B are front views showing the exit-side reflection type fly-eye optical system through an aperture stop. FIG. 4A is a front view showing an exit-side reflection type fly-eye optical system 20 through an aperture stop 18 in the fly-eye set A. FIG. 4B is a front view showing the replacement exit-side reflection type fly-eye optical system i 20 through the replacement aperture stop 118 in the replacement fly eye set B. As shown in FIG. 4A, when the effective diameter of the entrance optical surface of the exit-side reflective fly-eye optical system 20 is small, that is, when the diameter of the aperture of the aperture stop 18 is small, the exit-side reflective fly-eye optical system 20 has a small diameter. Eye optics 20 is small in size It is composed of element optical systems. That is, the focal length of the element optical system of the exit-side reflection type fly-eye optical system 20 is small. On the other hand, as shown in FIG. 4B, when the effective diameter of the entrance optical surface of the replacement exit-side reflection fly-eye optical system 120 is large, that is, when the aperture diameter of the replacement aperture stop 1 18 is large. The replacement emission-side reflection fly-eye optical system 120 is composed of a large-size element optical system. In other words, the focal length of the elemental optical system of the replacement exit-side reflection type fly-eye optical system 120 is large.
ここで、 フライアイセット Aにおける射出側反射型フライアイ光学系 2 0の要 素光学系の入射光学面の有効径と焦点距離との比率と、交換用フライアイセット Bにおける交換用射出側反射型フライアイ光学系 1 2 0の要素光学系の入射光 学面の有効径と焦点距離との比率とは、 一定である。 フライアイ光学系がその機 能をはたす為には、「最低限の数」の要素光学系が必要である。「最低限の数」は、 その装置の仕様やフライアイ光学系に入射する光束の強度分布によって異なる が、 半導体パターン擊光装置の照明系としては、 照明開口絞りの直径内に少なく とも 4列以上、 望ましくは 6列以上、 要素光学系が並ぶ必要がある。  Here, the ratio between the effective diameter of the entrance optical surface of the elemental optical system of the fly-eye set A in the fly-eye set A 20 and the focal length, and the replacement exit-side reflection in the replacement fly-eye set B The ratio between the effective diameter of the incident optical surface and the focal length of the element optical system of the type fly-eye optical system 120 is constant. In order for a fly-eye optical system to perform its function, a “minimum number” of element optical systems is required. The “minimum number” varies depending on the specifications of the device and the intensity distribution of the light beam incident on the fly-eye optical system. However, as the illumination system of a semiconductor pattern optical device, at least four rows within the diameter of the illumination aperture stop As described above, it is necessary to arrange the element optical systems in at least six rows.
開口が小さくなるときにあわせて、 要素光学系が必要数だけ並ぶよう、 個々の 要素光学系のサイズを決定すると、 開口が大きくなつたときには、 莫大な数の要 素光学系が並ぶこととなる。 図 8 Aは、 開口が小さくなるときに合わせて要素光 学系のサイズを決めた射出側反射型フライアイ光学系 2 0 9を、 開口絞り 2 0 8 を通して観察した図を示している。 図 8 Bは開口絞り 2 0 8の開口を大きなもの に切り替えた際の図を示している。 図 8 Bは、 前述の莫大な数の要素光学系が並 んだ例である。  If the size of each element optical system is determined so that the required number of element optical systems will line up when the aperture becomes smaller, an enormous number of element optical systems will be arranged when the aperture becomes larger. . FIG. 8A shows a view in which the exit-side reflection type fly-eye optical system 209 whose element optical system is sized in accordance with the decrease in the aperture is observed through the aperture stop 208. FIG. 8B shows a diagram when the aperture of the aperture stop 208 is switched to a large aperture. FIG. 8B is an example in which the huge number of element optical systems described above are arranged.
ここで、入射側反射型フライアイ光学系と射出側反射型フライアイ光学系の間 隔は、 それぞれの外径に対して十分放しておきたい。 なぜなら、 外径に対して間 隔が狭いと、 往復する光束の分離の為、 フライアイ光学系に対して極めて斜めに 光束が入射しなければならなくなるからである。 E U V用の反射膜は、 反射面に 対して入射光が垂直であるか又はほとんど水平である場合以外は極めて反射率 が悪くなる為、 4 5 ° 近傍の入射角は極力避けねばならない。 Here, it is desirable that the distance between the entrance-side reflection fly-eye optical system and the exit-side reflection fly-eye optical system be sufficiently large for the respective outer diameters. This is because if the distance is small relative to the outer diameter, the light beam must enter the fly-eye optical system at an extremely oblique angle to separate the light beam going back and forth. Reflective films for EUV have extremely high reflectivity unless the incident light is vertical or almost horizontal to the reflective surface. Therefore, the incident angle near 45 ° must be avoided as much as possible.
そこで入射側反射型フライアイ光学系と射出側反射型フライアイ光学系の間 隔を広げる為には、 要素光学系の数を極力減らさなければならない。 なぜなら、 個々の要素光学系が小さくなつても露光範囲が変わらない為には、 個々の要素光 学系の焦点距離が短くなければならないからである。 上述したように、 入射側反 射型フライアイ光学系の個々の要素光学系はマスク面と共役となる為、 個々の要 素光学系の焦点距離が短くなれば、 入射側反射型フライアイ光学系と射出側反射 型フライアイ光学系の間隔は狭めざるを得ない。  Therefore, in order to increase the distance between the entrance-side reflection fly-eye optical system and the exit-side reflection fly-eye optical system, the number of element optical systems must be reduced as much as possible. This is because the focal length of each element optical system must be short so that the exposure range does not change even if each element optical system becomes small. As described above, since each element optical system of the incident-side reflection fly-eye optical system is conjugate to the mask surface, if the focal length of each element optical system becomes shorter, the incident-side reflection fly-eye optical system becomes The distance between the system and the exit-side reflection fly-eye optical system must be reduced.
すなわち、 特開平 1 1— 3 1 2 6 3 8号公報で提案されているシステムにおい ては、 光学的な照明条件の最適化という観点では、 開口絞り 2 0 8の開口の可変 範囲を広くする為にフライアイ光学系の要素光学系の数を増やす必要がある力 現実的な系の設計解を得る為には極力要素光学系の数を減らす必要がある。 この 矛盾は、 投影光学系 2 8の開口数が大きくなるほど、 これに比例して照明光学系 の開口数も大きくなる為、 顕著となる。 この発明は、 この問題点を解決するもの であり、 上述の実施の形態はその例である。  In other words, in the system proposed in Japanese Patent Application Laid-Open No. H11-3123838, from the viewpoint of optimizing the optical illumination conditions, the variable range of the aperture of the aperture stop 208 is widened. For this reason, it is necessary to reduce the number of element optical systems as much as possible to obtain a realistic system design solution. This contradiction becomes more pronounced as the numerical aperture of the projection optical system 28 increases, and the numerical aperture of the illumination optical system increases in proportion thereto. The present invention solves this problem, and the above embodiment is an example.
すなわち、 照明系の開口絞り 2 0 8に大開口を使用する際には要素光学系のサ ィズを大きく し、 開口絞り 2 0 8に小開口を使用する際には要素光学系のサイズ を小さくすることで、 開口内の要素光学系の数と、 入射側反射型フライアイ光学 系と射出側反射型フライアイ光学系の間隔、 という二つの要請を共に上手くバラ ンスしている。 しかも、 要素光学系のサイズと要素光学系の焦点距離の比を一定 とすることで、 個々の要素光学系の光学的特性が同じになる為、 いずれのフライ アイセットを用いても、 マスク （レチクル） 上所定の領域のみを照明することが できる。  In other words, when using a large aperture for the aperture stop 208 of the illumination system, increase the size of the element optical system, and when using a small aperture for the aperture stop 208, increase the size of the element optical system. By reducing the size, the two requirements of the number of element optical systems in the aperture and the spacing between the entrance-side reflection fly-eye optical system and the exit-side reflection fly-eye optical system are well balanced. Moreover, by keeping the ratio between the size of the element optical system and the focal length of the element optical system constant, the optical characteristics of the individual element optical systems become the same, so that the mask ( (Reticle) Only a predetermined area can be illuminated.
なお、 この実施の形態においては、 フライアイセット及び 1つの交換用フライ アイセットを有する投影露光装置として説明したが、 2つ以上の交換用フライア ィセットを備えていてもよい。 この場合には、 複数のフライアイセットを水平平 面内に沿って回転可能なフライアイセットステージに保持させ、 そのフライアイ セットステージを回転させることにより複数のフライアイセットのいずれか 1 つのフライアイセットを設置する。 In this embodiment, the projection exposure apparatus has a fly eye set and one replacement fly eye set. However, two or more replacement fly eye sets may be provided. In this case, a plurality of fly eye sets are held on a fly eye set stage rotatable along a horizontal plane, and the fly eye sets are held. One of the fly eye sets is set by rotating the set stage.
また、 この実施の形態においてはフライアイセット Aを交換用フライアイセッ ト Bに交換したが、 集光光学系 1 4を含めない反射型フライアイ光学系 1 6 , 2 0及び開口絞り 1 8を、集光光学系 1 1 4を含めない反射型フライアイ光学系 1 1 6 , 1 2 0及び開口絞り 1 1 8に交換してもよい。  In this embodiment, the fly-eye set A is replaced with a replacement fly-eye set B. However, the reflective fly-eye optical systems 16 and 20 and the aperture stop 18 that do not include the focusing optical system 14 are The reflection type fly-eye optical systems 1 16 and 120 which do not include the condensing optical system 114 and the aperture stop 1 18 may be replaced.
この実施の形態にかかる投影露光装置によれば、 交換用反射型フライアイ光学 系を備えており照明光学装置の反射型フライアイ光学系を適宜交換することが できる。 従って、 マスクのパターンに最適な照明光の開口数を有している反射型 フライアイ光学系を備えた照明光学装置を用いて投影露光することができるた め、 開口絞りの可変範囲を広く設定した場合においてもフライアイ光学系に被覆 されている反射膜の高反射率を維持することができ、 高解像度及び十分な露光光 強度を有する投影露光装置を提供することができる。  According to the projection exposure apparatus of this embodiment, a reflection type fly-eye optical system for replacement is provided, and the reflection type fly-eye optical system of the illumination optical device can be appropriately replaced. Therefore, the projection exposure can be performed using an illumination optical device having a reflective fly-eye optical system having an optimal numerical aperture of the illumination light for the mask pattern. Even in this case, it is possible to maintain a high reflectance of the reflection film coated on the fly-eye optical system, and to provide a projection exposure apparatus having high resolution and sufficient exposure light intensity.
上述の実施の形態にかかる投影露光装置では、 E U V用照明光学装置によって マスクを照明し （照明工程）、 反射型投影光学系を用いてマスクに形成されたパ ターン像を感光性基板に投影する（投影工程） ことにより、マイクロデバィス（半 導体素子、 撮像素子、 液晶表示素子、 薄膜磁気ヘッド等） を製造することができ る。 以下、 この実施の形態にかかる投影露光装置を用いて感光性基板としてのゥ ェハ等に所定の回路パターンを形成することによって、 マイクロデバイスとして の半導体デバイスを得る際の手法の一例につき図 5のフローチヤ一トを参照し て説明する。  In the projection exposure apparatus according to the above-described embodiment, the mask is illuminated by the EUV illumination optical device (illumination step), and the pattern image formed on the mask is projected onto the photosensitive substrate using the reflective projection optical system. By performing the (projection step), a micro device (semiconductor element, imaging element, liquid crystal display element, thin film magnetic head, etc.) can be manufactured. Hereinafter, an example of a technique 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 projection exposure apparatus according to this embodiment will be described with reference to FIG. This will be described with reference to the flowchart of FIG.
先ず、 図 5のステップ S 3 0 1において、 1ロットのウェハ上に金属膜が蒸着 される。 次のステップ S 3 0 2において、 その 1ロットのウェハ上の金属膜上に フォトレジストが塗布される。 その後、 マスク上のパターン毎に最適な照明光の 開口数となるように適切なフライアイセットを設置し、 ステップ S 3 0 3におい て、 この実施の形態にかかる投影露光装置を用いて、 マスク上のパターン像がそ の反射型投影光学系を介して、 その 1ロットのウェハ上の各ショット領域に順次 投影露光される。 その後、 ステップ S 3 0 4において、 その 1ロットのウェハ上 のフォトレジストの現像が行われた後、 ステップ S 3 0 5において、 その 1ロッ トのウェハ上でレジストパターンをマスクとしてエッチングを行うことによつ て、 マスク上のパターンに対応する回路パターンが、 各ウェハ上の各ショット領 域に形成される。 First, in step S301 of FIG. 5, a metal film is deposited on one lot of wafers. In the next step S302, a photoresist is applied on the metal film on the wafer of the one lot. After that, an appropriate fly-eye set is installed so as to provide an optimum numerical aperture of illumination light for each pattern on the mask, and in step S303, the mask is set using the projection exposure apparatus according to this embodiment. The pattern image above is sequentially passed through the reflective projection optical system to each shot area on that one lot wafer. It is projected and exposed. Thereafter, in step S304, the photoresist on the one lot wafer is developed, and then in step S305, etching is performed on the one lot wafer using the resist pattern as a mask. Thus, a circuit pattern corresponding to the pattern on the mask is formed in each shot area on each wafer.
その後、 更に上のレイヤの回路ハ。ターンの形成等を行うことによって、 半導体 素子等のデバイスが製造される。 上述の半導体デバイス製造方法によれば、 極め て微細な回路パターンを有する半導体デバイスをスループット良く得ることが できる。 なお、 ステップ S 3 0 1〜ステップ S 3 0 5では、 ウェハ上に金属を蒸 着し、 その金属膜上にレジストを塗布、 そして露光、 現像、 エッチングの各工程 を行っているが、 これらの工程に先立って、 ウェハ上にシリコンの酸化膜を形成 後、 そのシリコンの酸化膜上にレジストを塗布、 そして露光、 現像、 エッチング 等の各工程を行っても良いことはいうまでもない。  Then, the circuit c on the upper layer. By forming a turn or the like, a device such as a semiconductor element is manufactured. According to the above-described semiconductor device manufacturing method, a semiconductor device having an extremely fine circuit pattern can be obtained with high throughput. In steps S301 to S305, a metal is vapor-deposited on the wafer, a resist is applied on the metal film, and the respective steps of exposure, development, and etching are performed. It is needless to say that prior to the process, after a silicon oxide film is formed on the wafer, a resist is applied on the silicon oxide film, and each process such as exposure, development, and etching may be performed.
また、 この実施の形態にかかる投影露光装置では、 プレート （ガラス基板） 上 に所定のパターン （回路パターン、 電極パターン等） を形成することによって、 マイクロデバイスとしての液晶表示素子を得ることもできる。 以下、 図 6のフロ 一チャートを参照して、 このときの手法の一例につき説明する。 図 6において、 パターン形成工程 S 4 0 1では、 この実施の形態の投影露光装置を用いて、 マス クのパターン毎に最適な照明光の開口数となるように適切なフライアイセット を設置し、マスクのパターンを感光性基板（レジストが塗布されたガラス基板等） に転写露光する、 所謂光リソグラフィ工程が実行される。 この光リソグラフイエ 程によって、 感光性基板上には多数の電極等を含む所定パターンが形成される。 その後、 露光された基板は、 現像工程、 エッチング工程、 レジスト剥離工程等の 各工程を経ることによって、 基板上に所定のパターンが形成され、 次のカラーフ ィルタ形成工程 S 4 0 2へ移行する。  In the projection exposure apparatus according to this embodiment, a liquid crystal display element as a micro device can be obtained by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate). Hereinafter, an example of the technique at this time will be described with reference to the flowchart of FIG. In FIG. 6, in the pattern forming step S401, using the projection exposure apparatus of this embodiment, an appropriate fly-eye set is installed so that an optimal numerical aperture of illumination light is obtained for each mask pattern. Then, a so-called photolithography step of transferring and exposing the pattern of the mask onto a photosensitive substrate (a glass substrate coated with a resist) is performed. By this photolithographic process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. Thereafter, the exposed substrate is subjected to a development process, an etching process, a resist stripping process, and other processes to form a predetermined pattern on the substrate, and the process proceeds to a next color filter forming process S402.
次に、カラーフィルタ形成工程 S 4 0 2では、 R (Red) , G (Green)、 B (Blue) に対応した 3つのドットの組がマトリックス状に多数配列されたり、 または R、 G、 Bの 3本のストライプのフィルタの組を複数水平走査線方向に配列されたり したカラーフィルタを形成する。 そして、 カラーフィルタ形成工程 S 4 0 2の後 に、 セル組み立て工程 S 4 0 3が実行される。 セル組み立て工程 S 4 0 3では、 パターン形成工程 S 4 0 1にて得られた所定パターンを有する基板、およびカラ 一フィルタ形成工程 S 4 0 2にて得られたカラーフィルタ等を用いて液晶パネ ル （液晶セル） を組み立てる。 セル組み立て工程 S 4 0 3では、 例えば、 パター ン形成工程 S 4 0 1にて得られた所定パターンを有する基板とカラーフィルタ 形成工程 S 4 0 2にて得られたカラーフィルタとの間に液晶を注入して、液晶パ ネル （液晶セル） を製造する。 Next, in the color filter forming step S402, a large number of sets of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix, or R, A color filter is formed by arranging a plurality of sets of three stripe filters of G and B in the horizontal scanning line direction. After the color filter forming step S402, a cell assembling step S403 is performed. In the cell assembling step S403, the liquid crystal panel is formed using the substrate having the predetermined pattern obtained in the pattern forming step S401, the color filter obtained in the color filter forming step S402, and the like. (Liquid crystal cell). In the cell assembling step S 403, for example, a liquid crystal is interposed between the substrate having the predetermined pattern obtained in the pattern forming step S 401 and the color filter obtained in the color filter forming step S 402. To manufacture a liquid crystal panel (liquid crystal cell).
その後、モジュール組み立て工程 S 4 0 4にて、組み立てられた液晶パネル（液 晶セル） の表示動作を行わせる電気回路、 バックライト等の各部品を取り付けて 液晶表示素子として完成させる。 上述の液晶表示素子の製造方法によれば、 極め て微細な回路パターンを有する液晶表示素子をスループット良く得ることがで さる。  Then, in a module assembling step S404, 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 good throughput.
なお、 本仕様書中に記載した、 「反射型フライアイ光学系の要素光学系の入射 光学面の有効径」 とは、 上記実施の形態の図 3 A及ぴ図 3 Bで示した要素光学系 の横幅、 Wm又は W f と呼称しているが、 Wm又は W f に直交する方向の幅、 あ るいは斜め方向の幅を有効径と呼称してもよレ、。  The “effective diameter of the entrance optical surface of the elemental optical system of the reflective fly-eye optical system” described in this specification is the elementary optical element shown in FIGS. 3A and 3B of the above embodiment. Although the width of the system is called Wm or Wf, the width in the direction perpendicular to Wm or Wf or the width in the oblique direction may be called the effective diameter.
この発明の照明光学装置によれば、交換用反射型フライアイ光学系を備えてお り照明光学装置の反射型フライアイ光学系を適宜交換することができる。従って、 マスクのパターンに最適な照明光の開口数を有している反射型フライアイ光学 系を備えた照明光学装置を提供することができる。  ADVANTAGE OF THE INVENTION According to the illumination optical device of this invention, the reflection type fly-eye optical system for replacement is provided, and the reflection type fly-eye optical system of an illumination optical device can be replaced suitably. Therefore, it is possible to provide an illumination optical device having a reflective fly-eye optical system having an optimum numerical aperture of illumination light for a mask pattern.
また、 この発明の投影露光装置によれば、 この発明の照明光学装置を備えてい るため、交換用反射型フライアイ光学系を備えており照明光学装置の反射型フラ ィアイ光学系を適宜交換することができる。 従って、 マスクのパターンに最適な 照明光の開口数を有している反射型フライアイ光学系を設置し投影露光するこ とができるため、 高解像度及び十分な露光光強度を有する投影露光装置を提供す ることができる。 Further, according to the projection exposure apparatus of the present invention, since the illumination optical device of the present invention is provided, a replacement reflective fly-eye optical system is provided, and the reflective fly-eye optical system of the illumination optical device is appropriately replaced. be able to. Accordingly, since a reflective fly-eye optical system having an optimum numerical aperture of illumination light for a mask pattern can be installed and exposed for projection, a projection exposure apparatus having high resolution and sufficient exposure light intensity can be provided. Offer Can be
また、 この発明の露光方法によれば、 この発明の照明光学装置を備えている投 影露光装置を用い、 その照明光学装置が露光パターンに最適な照明光の開口数を 有しているため、 微細な露光パターンの露光を良好に行うことができる。 産業上の利用可能性  According to the exposure method of the present invention, a projection exposure apparatus having the illumination optical device of the present invention is used, and the illumination optical device has an optimum numerical aperture of illumination light for an exposure pattern. Exposure of a fine exposure pattern can be favorably performed. Industrial applicability
以上のように、 この発明の照明光学装置、 該照明光学装置を用いた投影露光装 置及び該投影露光装置用いた露光方法は、半導体素子、撮像素子、液晶表示素子、 薄膜磁気へッド等のデバイスの製造に用いるのに適している。  As described above, the illumination optical device of the present invention, the projection exposure apparatus using the illumination optical device, and the exposure method using the projection exposure device include a semiconductor device, an image sensor, a liquid crystal display device, a thin-film magnetic head, and the like. Suitable for use in the manufacture of devices.

Claims

請求の範囲 The scope of the claims
1 . 極紫外光を照明光としてマスクを照明する照明光学装置であって、 並列に配列された複数の要素光学系を有する反射型フライアイ光学系と、 並列に配列された複数の要素光学系を有する交換用反射型フライアイ光学系 と、 1. An illumination optical device for illuminating a mask using extreme ultraviolet light as illumination light, comprising: a reflective fly-eye optical system having a plurality of element optical systems arranged in parallel; and a plurality of element optical systems arranged in parallel. A replacement reflective fly-eye optical system having
前記反射型フライアイ光学系と前記交換用反射型フラィアイ光学系を交換す るフライアイ光学系交換手段とを備え、  A fly-eye optical system exchanging means for exchanging the reflective fly-eye optical system and the replacement reflective fly-eye optical system,
前記反射型フラィアイ光学系の要素光学系は前記交換用反射型フライアイ光 学系の要素光学系と異なる焦点距離を有し、  The element optical system of the reflective fly's eye optical system has a different focal length from the element optical system of the replacement reflective fly's eye optical system,
前記反射型フライアイ光学系の要素光学系の入射光学面の有効径と焦点距離 の比率と、 前記交換用反射型フライアイ光学系の要素光学系の入射光学面の有効 径と焦点距離の比率が一定であることを特徴とする照明光学装置。  The ratio between the effective diameter and the focal length of the incident optical surface of the element optical system of the reflective fly-eye optical system, and the ratio of the effective diameter and the focal length of the incident optical surface of the element optical system of the replacement reflective fly-eye optical system. The illumination optical device, wherein is constant.
2 . 前記フライアイ光学系交換手段は、 前記反射型フライアイ光学系及ぴ前 記反射型フライアイ光学系の前段に位置する光学部材を前記交換用反射型フラ ィアイ光学系及び前記交換用反射型フライアイ光学系の前段に位置する交換用 光学部材に交換することを特徴とする請求項 1に記載の照明光学装置。  2. The fly-eye optical system exchanging means includes: the reflection-type fly-eye optical system; and the optical member located at a stage preceding the reflection-type fly-eye optical system. 2. The illumination optical device according to claim 1, wherein the illumination optical device is replaced with a replacement optical member located upstream of the mold fly-eye optical system.
3 . 極紫外光を照明光としてマスクを照明する照明光学装置であって、 並列に配列された複数の要素光学系を有する反射型フライアイ光学系と、 前記反射型フライアイ光学系と前記マスクとの間に配置されたコンデンサー 光学系とを備え、  3. An illumination optical device for illuminating a mask using extreme ultraviolet light as illumination light, the reflective fly-eye optical system having a plurality of element optical systems arranged in parallel, the reflective fly-eye optical system and the mask With a condenser optics placed between
前記コンデンサー光学系の焦点距離を F c o n , 前記マスク上の露光範囲の最 長横幅を wmとするとき、 以下の条件を満足することを特徴とする照明光学装置  When the focal length of the condenser optical system is F con, and the maximum width of the exposure range on the mask is wm, the following conditions are satisfied:
F c o n > 8 wm F c o n> 8 wm
4 . 請求項 1乃至請求項 3のいずれか一項に記載の照明光学装置  4. The illumination optical device according to any one of claims 1 to 3.
と、 マスクのパターン像を感光性基板上に形成する反射型投影光学系と、 を備えることを特徴とする投影露光装置。 When, And a reflection type projection optical system for forming a pattern image of a mask on a photosensitive substrate.
5 . 請求項 4に記載の投影露光装置を用いた露光方法において、  5. An exposure method using the projection exposure apparatus according to claim 4,
前記照明光学装置により前記マスクを照明する照明工程と、  An illumination step of illuminating the mask with the illumination optical device;
前記反射型投影光学系により前記マスクのパターン像を前記感光性基板上に 投影する投影工程と、  A projecting step of projecting the pattern image of the mask onto the photosensitive substrate by the reflective projection optical system;
を含むことを特徴とする露光方法。 An exposure method comprising:
PCT/JP2004/004835 2003-04-04 2004-04-02 Illuminating optical device, projection exposure system and exposure method WO2004090955A1 (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006165552A (en) * 2004-12-02 2006-06-22 Asml Netherlands Bv Lithography equipment and method for manufacturing device
JP2007335792A (en) * 2006-06-19 2007-12-27 Matsushita Electric Ind Co Ltd Thin-film solar cell
JP2012114198A (en) * 2010-11-24 2012-06-14 Nikon Corp Optical unit, optical system, exposure device, and method of manufacturing device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6470058A (en) * 1987-08-07 1989-03-15 Ciba Geigy Ag Container for medicine
JP2000162415A (en) * 1998-09-22 2000-06-16 Nikon Corp Manufacture of reflection mirror or reflection type lighting system or semiconductor exposing device
JP2003045774A (en) * 2001-07-27 2003-02-14 Canon Inc Illumination device, projection aligner and device manufacturing method
JP2003045784A (en) * 2001-07-31 2003-02-14 Canon Inc Illumination system, aligner, and device-manufacturing method
JP2003506881A (en) * 1999-07-30 2003-02-18 カール ツァイス シュティフトゥング トレイディング アズ カール ツァイス Control of illumination distribution at exit pupil of EUV illumination optical system
JP2003309057A (en) * 2002-04-15 2003-10-31 Canon Inc Projection aligner and device-manufacturing method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6470058A (en) * 1987-08-07 1989-03-15 Ciba Geigy Ag Container for medicine
JP2000162415A (en) * 1998-09-22 2000-06-16 Nikon Corp Manufacture of reflection mirror or reflection type lighting system or semiconductor exposing device
JP2003506881A (en) * 1999-07-30 2003-02-18 カール ツァイス シュティフトゥング トレイディング アズ カール ツァイス Control of illumination distribution at exit pupil of EUV illumination optical system
JP2003045774A (en) * 2001-07-27 2003-02-14 Canon Inc Illumination device, projection aligner and device manufacturing method
JP2003045784A (en) * 2001-07-31 2003-02-14 Canon Inc Illumination system, aligner, and device-manufacturing method
JP2003309057A (en) * 2002-04-15 2003-10-31 Canon Inc Projection aligner and device-manufacturing method

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006165552A (en) * 2004-12-02 2006-06-22 Asml Netherlands Bv Lithography equipment and method for manufacturing device
JP2007335792A (en) * 2006-06-19 2007-12-27 Matsushita Electric Ind Co Ltd Thin-film solar cell
JP2012114198A (en) * 2010-11-24 2012-06-14 Nikon Corp Optical unit, optical system, exposure device, and method of manufacturing device

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