TW584898B - Optical system and exposure apparatus having the optical system - Google Patents

Abstract

The purpose of the present invention is to provide a kind of optical system capable of assuring excellent optical performance without being substantially influenced by the birefringence even when the crystalline material having birefringence quality such as fluorite is used. The invented optical system (100) contains the followings: plural crystallized optical devices formed by the cubic crystal series; the crystallized optical devices (105, 106), in which the first crystal axis is the same as the optical axis; and the crystallized optical devices (109, 110), in which the second crystal axis is the same as the optical axis. In order to substantially avoid the influence of birefringence, for the first evaluation quantity SigmaRj associated with the sum of the first evaluation quantity Rj of plural crystalline optical devices and for the second evaluation quantity SigmaSj associated with the sum of the second evaluation quantity Sj of plural crystalline optical devices, a certain relationship is provided in the light of the image formation light beam focused on at least one arbitrary point of the image surface or of the object surface of the optical system.

Description

584898 A7 _B7 V. INTRODUCTION TO THE INVENTION (TECHNICAL FIELD OF THE INVENTION) The present invention relates to an optical system and an exposure device provided with the optical system, and particularly to a micro device for manufacturing a semiconductor device, a liquid crystal display device, etc. by a photolithography process. It is suitable for the optical system of the exposure device to be used. The prior art The prior art uses a method which is to be formed when the micropatterns of electronic components (microdevices) such as semiconductor integrated circuits and liquid crystal displays are formed. The pattern of a photomask (also known as a light screen) drawn by enlarging the pattern ratio by about 4 to 5 times is reduced by exposure using a projection exposure device and transcribed onto a photosensitive substrate (substrate to be exposed) such as a wafer. In this projection The exposure device, in order to correspond to the miniaturization of semiconductor integrated circuits, its exposure wavelength is constantly shifted to the shorter wavelength. At present, although the exposure wavelength is mainly 248 nm of KrF excimer laser, the shorter wavelength ArF standard The molecular laser 1 93 nm is also entering the practical stage. In addition, there are also proposals to use a wavelength of 1 5 7 nm A projection exposure device for a light source in a wavelength band called a so-called vacuum ultraviolet region, such as an F 2 laser and an A 2 laser with a wavelength of 126 nm. Furthermore, because of the large opening number (NA) of the projection optical system, Since it can achieve high resolution, it is not only for the development of a shorter wavelength for the exposure wavelength, but also for a projection optical system with a larger number of apertures. Thus, for the exposure ratio in the ultraviolet region with a short wavelength, it is necessary to limit the transmittance, Optical material (lens material) with good uniformity. Although it can also be used as a lens in projection optical systems using ArF excimer laser as a light source-This paper is compliant with China National Standard (CNS) A4 (210X 297) Public Love) " " " " — Binding

¢ 84898 A7 B7 V. Description of the invention (Material of synthetic quartz glass, but there are some lenses using calcium fluoride crystal (fluorite). On the other hand, in the projection optical system with h laser as the light source ' The lens material that can be used is actually limited to calcium fluoride junction (fluorite). Recently, it is reported that the invention is to solve the problem of short-wavelength ultraviolet rays. Stone), also produces birefringence. The super high-precision optical system like the projection optical system used in the manufacture of electronic components, the aberrations caused by the birefringence of the lens material are a fatal problem, and actually avoid the birefringence. The lens configuration and lens design that are affected by refraction are indispensable. The present invention is an invention made in view of the aforementioned problems, and an object thereof is to provide an optical system and an exposure apparatus including the optical system, which are used even if, for example, an image is used. It is a birefringent crystalline material of fluorite, and can also ensure good optical performance without being substantially affected by birefringence. In addition, the present invention An object of the present invention is to provide a method for manufacturing a microdevice, which is an exposure device equipped with an optical system that uses crystalline materials and has good optical performance. With the high-resolution exposure technology, a high-performance microdevice can be manufactured. In order to solve the above problems, in the first invention of the present invention, in an optical system including a plurality of crystalline optical elements formed by crystals belonging to a cubic crystal series, the plurality of crystalline optical elements include: a first crystal axis and the optical The optical axis of the system is set to approximately the same crystalline optical element, and the second knot • 5-This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) binding

The optical axis is set to be approximately the same as the crystalline optical crystal axis and the element of the optical system, and the majority of the crystalline optical element Gj is in a specific crystalline 表面 direction on a surface orthogonal to the light, and for the The specific axis and gimbal are arranged with the rotation angle pj centered on the optical axis, and the angle formed by the specific light and the direction of the optical axis is regarded as the specific light passing through the majority of the m-science elements Gj. When ^ is set, the angle formed by the specific light and the specific ㈣ direction is regarded as 0J, and the diameter of the light pattern of the specific light is taken as ㈣. For the physical property constant α, The angle p ", the angle ej, the angle 0j, and the first evaluation of the fixed-polarized light #Rj determined by the diameter of the light pattern and the second evaluation of the second-defined polarized light The evaluation amount Sj provides a total of the first total evaluation amount sRj of the above-mentioned first evaluation amount RJ of the plurality of crystalline optical elements and a total of the second evaluation amount Sj of the majority of the crystalline optical elements. Second evaluation value sum SSj, collecting any material on at least one point on the surface of the optical system or the image of an object surface of the imaging light beam has a specific relationship. According to an ideal form of the first invention, the above-mentioned "solid evaluation amount ⑴" is the change information of the light pattern diameter and length for the first certain polarized light; the second evaluation amount Sj is for the second certain polarized light. Information about the change in the diameter of the light pattern. In addition, it is desirable that the first certain polarized light is R polarized light having a polarization direction in a circle diameter direction centered on the optical axis; and the second certain polarized light is at Circumference around the above optical axis 584898 A7 B7

V. Description of the invention Polarized light has a polarized direction Θ. Furthermore, the relationship between the above-mentioned chemical and industrial scales desirably includes the following relationship: the sum of the above-mentioned first evaluation amount ... is focused on the image surface or the object surface of the optical system The light rays in the imaging beam of at least any i points are approximately equal. For the above-mentioned second \ sum evaluation value ESj, at least any one point on the image surface or object surface of the optical system The rays in the imaging beam have approximately equal relationships, and the sum of the above-mentioned first evaluation quantity Rj and the above-mentioned second total evaluation {beam quantity Σ S j for light on the image surface or object surface of the above-mentioned optical system The rays in the imaging beam of at least any one point are approximately equal. In addition, according to an ideal form of the first invention, if the optical axis and the crystal axis [111] or a crystal axis optically equivalent to the crystal axis are set to approximately the same crystal optical element Gj, the above-mentioned constant crystal The axis is the crystal axis [-110] or a crystal axis which is optically equivalent to the crystal axis. When ω j = 0 j _ pj, the first evaluation amount Rj and the second evaluation amount Sj are respectively as follows: Expression. Equation 3

Rj = a > < Ljx [56x {l-cos (4 0j)} -32 / " 2 > < sin (4 0j) xsin (36L) j)] / 192 Sj = axLjx [32x {l- cos (2 0j)} + 64 / 2xsin (2 0j) xsin (3wj)] / 192 Furthermore, according to the ideal form of the first invention, in the above optical axis and crystal axis [0 01] or with the crystal The optically equivalent crystal extraction of the axis is sufficient to be approximately the same as the crystalline optical element Gj. The above specific crystal axis is crystal. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 male father) 584898 A7 B7 Five Explanation of the invention (5) The axis [110] or a crystal axis optically equivalent to the crystal axis, when coj = 0j-pj, the above-mentioned first evaluation amount Rj and the above-mentioned second evaluation amount Sj are respectively less than Column expression.

Rj = axLjx {l-cos (4 0j)} x {-84-12xcos (46; j)} / 192 Sj = a xLjx {l-cos (2 0j)} x {-48 + 48xcos (46; j) } / 192 According to an ideal form of the first invention, if the optical axis and the crystal axis [011] or the crystal axis optically equivalent to the crystal axis are set to approximately the same crystal optical element Gj, the above The specific crystal axis is the crystal axis [100] or a crystal axis which is optically equivalent to the crystal axis. When ω j == 0 j -pj, the above-mentioned first evaluation amount Rj and the above-mentioned second evaluation The quantities Sj are expressed by the following formulas, respectively. Formula 4

Rj = axLjx [{l-cos (4 0j)} x {21-9xcos (4wj) -84xcos (26; j)} + 96xcos (2 ^ j)] / 192

Sj = a xLjx [{l-cos (2 0j)} x {12 + 36xcos (46; j) + 48xcos (2gj)} -96xcos (2oj)] / 192 In addition, according to the ideal form of the first invention, The physical property constant α of the crystal is among the light traveling in the direction of the crystal axis [011] or the crystal axis optically equivalent to the crystal axis in the crystal forming each crystal optical unit Gj, and the crystal axis [100] ] Or the crystal axis is optically equivalent to the direction of the crystal axis and has a refractive index η 100 of the polarization direction of light, and the crystal axis is equivalent to the crystal axis [0-11] or is optically equivalent to the crystal axis. The direction of has a difference in the refractive index η 011 of the light in the polarization direction. In addition, when the wavelength of light is the same, the above-mentioned first total evaluation quantity Σ Rj and the above-mentioned second total -8- This paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) binding

584898 A7

The absolute value of the difference between the evaluation amounts ZSj is desirably set to be smaller than λ / 2 in the imaging beam focused on at least any one point on the image surface or the object surface of the optical system described above. Furthermore, according to the ideal form of the first invention, when the wavelength of light is λ, the absolute value of the difference between the first sum evaluation value Σ Rj and a certain value is' for condensing the light in the optical system. The light rays in the imaging beam of at least any one point on the image surface or the object surface are set to be smaller than λ / 2. In addition, when the wavelength of light is constant, it is desirable that the absolute value of the difference between the second sum evaluation value Σ Sj and a certain value is focused on the image surface or object surface of the optical system. The light rays in the imaging beam of at least any one point are set smaller than λ / 2. In addition, according to an ideal form of the first invention, the optical system 'including the optical axis and the crystal axis [111] or a crystal axis optically equivalent to the crystal axis is set to approximately the same M (M is 3 The crystalline optical element of the above (integer) sheet, the crystalline optical element of the M sheet has a crystal axis [1-10] in a plane perpendicular to the optical axis, or a crystal axis optically equivalent to the crystal axis Directions are rotationally related to each other at approximately (120 / M) degrees apart from each other around the above-mentioned optical axis. Furthermore, according to an ideal form of the first invention, the optical system includes the optical axis and the crystal axis [00] or a crystal axis that is optically equivalent to the crystal axis and is set to approximately the same N ( N is an integer of 3 or more), and the crystalline optical element of the N sheet has a crystal extraction [100] in a plane perpendicular to the optical axis or a crystal optically equivalent to the crystal axis. The directions of the axes are approximately (90 / N) -9 from each other with the above-mentioned optical axis as the center.-This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 public attack) 584898 A7 _______ B7__ V. Description of the invention (7) Separate rotation position relationship. In addition, according to an ideal form of the first invention, the optical system 'including the optical axis and the crystal axis [011] or a crystal axis which is optically equivalent to the crystal axis is set to approximately the same L (L is 3 The crystalline optical element of the above) sheet, the crystalline optical element of the L sheet has a direction of the crystal axis [10 0] in a plane perpendicular to the optical axis, or a direction of the crystal axis optically equivalent to the crystal axis Rotating positional relationships separated by approximately (180 / L) degrees from each other with the optical axis as the center. Furthermore, according to an ideal form of the first invention, the optical system 'including the optical axis and the crystal axis [011] or a crystal axis which is optically equivalent to the crystal axis is set to approximately the same P (P is 2 or more) of the crystalline optical element, the crystalline optical element of the P sheet having a crystalline axis [100] in a plane perpendicular to the optical axis or a crystal axis optically equivalent to the crystalline axis Directions are rotationally related to each other at approximately (90 / p) degrees apart from each other with the optical axis as a center. In the second invention of the present invention, an optical system including a plurality of crystalline optical elements formed by crystals belonging to the cubic crystal series is characterized in that it provides an optical system including the optical axis and the crystal axis [111] or This crystal axis is optically equivalent. The crystal axis is set to a crystalline optical element of approximately uniform M (M is an integer of 3 or more) pieces. The crystalline optical element of the M sheet has crystals in a plane perpendicular to the optical axis. The axis [1-10] or the direction of the crystal axis that is optically equivalent to the crystal axis is a rotational position relationship separated by approximately (120 / M) degrees from each other with the optical axis as a center. ___ -10-The paper size is suitable for S ® Home Standard (CNS) A4 specification (21G X 297 public attack) " " 584898 A7 _ B7 V. Description of the invention (8) In the third invention of the present invention, An optical system including a plurality of crystalline optical elements formed by crystals belonging to the cubic crystal series is characterized by providing an optical system including the above-mentioned optical axis and crystal axis [〇〇1] or optically equivalent to the crystal axis The effective crystalline axis is set to approximately uniform crystalline optical elements of N (N is an integer of 3 or more) pieces, and the crystalline optical elements of the N pieces have a crystalline axis [10 0] in a plane perpendicular to the optical axis or It is a rotational position relationship in which the directions of the crystal axes which are optically equivalent to the crystal axes are separated by approximately (90 / N) degrees from each other with the optical axis as a center. In a fourth invention of the present invention, an optical system including a plurality of crystalline optical elements formed by crystals belonging to a cubic crystal series is characterized in that it provides an optical system including the optical axis and the crystal axis [0U] or This crystal axis is optically equivalent to a crystalline optical element having approximately the same L (L is an integer of 3 or more) pieces. The crystalline optical element of the L sheet has crystals in a plane perpendicular to the optical axis. The axis [100] or the direction of the crystal axis which is optically equivalent to the crystal axis is a rotation position relationship separated from each other by approximately (1 80 / L) degrees with the optical axis as a center. The fifth invention of the present invention is an optical system including a plurality of crystalline optical elements formed by crystals belonging to a cubic crystal series, and an optical system including the optical axis and the crystal axis [011] or It is a crystalline optical element having P (P is an integer of 2 or more) sheets whose crystalline axis is optically equivalent to the crystalline axis, and the crystalline optical element of the P sheet is in a plane perpendicular to the optical axis. This paper size applies to the SS family standard (CNS) A4 specification (210 X297 mm) " 584898 A7 B7 5. The crystal axis [100] of the description of the invention (9) or a crystal axis optically equivalent to the crystal axis The directions of rotation are rotationally related to each other by about (90 / p) degrees with the optical axis as the center. Furthermore, in the first invention to the fifth invention, it is desirable that the crystalline optical element of two or more crystalline optical elements has a rotation error within ± 4 degrees of each element, or a crystalline optical axis that should coincide with the optical axis. The angle error from the optical axis is within 4 degrees. According to the preferred embodiments of the first to fifth inventions, the crystal is preferably a calcium fluoride crystal or a barium fluoride crystal. Furthermore, it is desirable to provide at least one concave mirror. In addition, it is ideal to make the best aberration correction for the vibration wavelength of the ArF excimer laser, or the best aberration correction for the vibration wavelength of the dagger laser. According to a sixth invention of the present invention, there is provided an exposure apparatus including an illumination system for illuminating a mask, and a first invention for forming an image of a pattern formed on the mask on a photosensitive substrate. ~ The fifth invention of the optical system. Λ In a seventh invention of the present invention, there is provided a method for manufacturing a microdevice, which includes an exposure step of exposing the pattern of the mask to the photosensitive substrate using the exposure apparatus of the sixth invention, and A developing step of developing the photosensitive substrate exposed by the exposure device. The embodiment of the present invention will be described with reference to the accompanying drawings. 1 is a diagram schematically showing the configuration of the projection optical system provided with each embodiment of the present invention. The projection optical system mounted on the exposure apparatus is applicable to each embodiment of the present invention. If you refer to the picture! Words: Chinese National Standard (CNS) A4 specification "King Gongai" of Guanben Paper -12- 584898 5. Description of the invention (exposure device of each embodiment, equipped with light sources such as ArF excimer laser, dagger laser, etc. 1. The light beam supplied by the light source 丨 is guided to the illumination optical system 3 after passing through the backlight system 2. The illumination optical system 3 is a bending inflection mirror 3a and 3b shown in the figure, and an optical integrator (not shown) ( The photometric equalization element is used to illuminate the optical network (mask) 101 with approximately the same luminous intensity. The optical network 101, for example, is supported by the optical network frame 4 by vacuum suction, and is supported by the optical network stage 5. The light beam transmitted through the optical network 丨 〇 丨 is condensed by the projection optical series 300 and formed on a photosensitive substrate like a semiconductor wafer 102 to form a projection image of a pattern on the optical network 101. Wafer ι〇 2 is also supported by the wafer holder 7 by vacuum suction, for example, and is movable by the action of the wafer stage 8. In this way, by moving the wafer 102 step by step while performing overall exposure, it is possible to Optical net 1〇1 pattern cast The images are sequentially transcribed into each exposure area of the wafer 102. In addition, for the projection optical system 300, scanning exposure (Scan exposure) can be performed by moving the optical screen 101 and the wafer while relatively moving, so that the pattern of the optical screen 101 can be projected The images are sequentially transcribed to each exposure area of the wafer 102. In actual exposure of the electronic device circuit pattern, it is necessary to correctly position the pattern of the next step on the pattern formed in the previous step, so Positioning microscope 1 is mounted so that the detection mark position on wafer 102 can be accurately detected by the exposure device. F2 laser, ArF excimer laser (or eight 1_2 laser with wavelength of 126 〇111, etc.) is used as the light source i. The light pattern diameter of the light transmission system 2, the illumination optical system 3, and the projection optical system is, for example, an inert gas such as nitrogen, the paper size, the paper standard (CNS), the M specification (21QX tear public director) -13-584898 A7 B7 • 14- V. Description of the invention (except for u. In particular, when using F 2 laser, optical network 1 〇1, optical network frame 4 and optical network stage 5 ′ through box 6 With outside air The internal space of the box 6 is also removed by the inert gas. Similarly, the wafer 10, the wafer holder 7, and the wafer stage 8 are isolated from the outside air by the box 9, and the internal space of the box 9 is also inactive. Gas Removal ^ FIG. 2 is a diagram schematically showing the configuration of a projection optical system according to the first embodiment of the present invention. In FIG. 2, two axes are set parallel to the projection optical system 100 (corresponding to the figure). The optical axis AX100 of the projection optical system 1 of 1), the drawing surface of FIG. 2 in a surface where the X axis is parallel to the vertical z axis, and the drawing surface of FIG. 2 in a surface where the Y axis is perpendicular to the vertical Z axis. Then, the + Z axis is downward in the figure, the + χ axis is right in the figure, the + γ axis is from the front of the paper toward itself, and the XYZ coordinate system constitutes the right-hand coordinate system as a whole (hereinafter, referred to as the "right-hand rule"). In the first embodiment, for an ArF laser having a wavelength of 193 nm, a refractive-type projection optical system optimized for aberration correction is applicable to the present invention. In the first projection optical system of the implementation mode, 〇〇〇, the light beam emitted from the upper 丨 point of the optical network 丨 〇 丨 is arranged along the optical axis AX100 through the lens 103 ~ 11〇, focused on the light Point on the semiconductor wafer 102 of the flexible substrate. In this way, a projection image of a pattern drawn on the optical net 100 is formed on the wafer 102. In the first solid state, among the lenses 103 ~ 1, the lenses 105, 106, 109, and 10 are formed of calcium fluoride crystal (fluorite), and other lenses are formed of synthetic quartz glass, hereinafter referred to as fluorescent The lens formed by the stone is a crystalline lens. In addition, the pupil surface ρ P is approximately the optical Fourier transform surface for the optical network 丨 〇 丨 and the wafer (photosensitive substrate) 102. Here, the Chinese national standard (CNS ) A4 size (210X297mm) binding

584898 A7 B7 V. Description of the invention (Enough to configure the aperture. As mentioned before, "Luo Shi has birefringence for short-wavelength light beams ^ but" for the crystal axes of fluorite crystals [丨 〇〇] and [丨 丨 丨The light traveling in the direction of "] does not produce birefringence (refractive index difference between two beams with orthogonal polarizing planes). Therefore, the crystal axis [111] or [100] of the crystal lens (crystal optical system) and If the optical axis AX 100 of the projection optical system (and thus the optical axis of the crystal lens) is set to the same value, it will not cause birefringence for light traveling in parallel with the optical axis i 00. Conversely, for light along the crystal axis [ 〇11] The amount of birefringence of the imaging light is maximized. However, in order to improve the resolution of the projection optical system 100, it is necessary to enlarge the so-called maximum incident angle of the light beam to the wafer 102 (see FIG. 2). Sinusoidal; like this NA (the numerical aperture on the image side). By the way, the imaging beam emitted from 1 point on the optical network 101 and focused on the wafer 102 is based on the maximum incidence to the wafer 102 Angle 01〇〇 as specified The range of the image beam is expanded (the range from the imaging beam 100 to 1001 in FIG. 2), and it becomes the lens through the composition; the optical series 1 lens 100 to 100. Therefore, regarding the It is impossible to set the direction of all imaging beams (100 m to 100 R) parallel to the optical axis AX100. In fact, about arbitrary imaging rays The light pattern diameter in the lens 105 is 105 m, the light pattern diameter in the crystal lens 106 is 106 m, the light pattern diameter in the crystal lens 10 is 10 m, and the light pattern diameter in the crystal lens 11 is 110 m, which is not parallel to the optical axis AX100. As a result, the imaging light ray of 100 m has a light pattern diameter change (light pattern diameter length change) that is caused by the birefringence caused by fluorite crystals. -15- This paper Standards apply to China National Standard (CNS) A4 specifications (210X297 public love)

584898 A7 B7

The other imaging rays in the imaging beam (100L ~ 100R) are also transmitted through the crystal lens 105, 106, 10, and 110, and the light pattern diameter changes due to the birefringence of the fluorite crystal . In this case, as for other imaging light rays, the angle formed with the light pattern diameter and the optical axis AX 100 in each crystal lens is generally different from that of the imaging light rays of 100 m. The light pattern diameter varies from case to case. In this way, with regard to the fact that each imaging light beam in the imaging beam (from 100L to 100R) accepts a different light pattern, which has a long variation, that is, the occurrence of wavefront aberrations in the imaging beam, together with The resolution of the projection optical system 100 can be reduced. Such an amount of birefringence is accurately obtained from the relationship between the exposure wavelength λ, the crystal direction of the fluorite and the direction of progress of the light beam, and the polarization direction of the light beam. However, it is obtained by using two layers of tensors determined from the crystallographic direction of fluorite and the direction of the light beam, and most of the rotations in order to rotate the tensor in the three-dimensional space. Optical design indicators use extremely complex calculation methods. The inventors of the present invention have found that the above-mentioned amount of birefringence can be expressed by a simple expression described below. Therefore, by satisfying the optical design of this formula, it was found that a design of an optical system is feasible, which does not actually cause an adverse effect of the birefringence amount even when a crystalline lens is used. * 'The formula for calculating the birefringence of the upper part differs depending on whether or not the crystal axis of the crystal lens is approximately the same as the optical axis (hereinafter referred to as the z-axis) of the optical system. Therefore, referring to Fig. 3, the name of the crystal axis and the like on a crystal of a cubic system such as fluorite will be described. The unit cell of the cubic system is

584898 A7 B7 V. Description of the invention (The crystal structure in which the directions of the sides of the cube are periodically arranged. The sides of the cube are orthogonal to each other, and the sides are regarded as Xa axis, Ya axis, Za axis. At this time X The + direction of the a axis is the direction of the crystal axis [100], the + direction of the γ & axis is the direction of the crystal axis [010], and the + direction of the Za axis is the direction of the crystal axis [001]. More general For example, when the azimuth vector (xl, y 1, ζ υ) is taken on the (Xa, Ya, Za) right-handed mark system described above, the direction becomes the direction of the crystal axis (χ 1, y1, ζ 1). For example, crystal The direction of the axis [111] is consistent with the azimuth vector (1, 1, 1). In addition, the direction of the crystal axis [u_2] is the same as the azimuth vector (1, 1,-2). Of course, in the crystal of the cubic series, χ The a-axis, the ya-axis, and the za-axis are completely equivalent to each other regardless of optical and mechanical properties, and no distinction can be made in the crystallization of the intersect. Furthermore, such as the crystallization axis [011] '[0-11], [110] The three crystal numbers juxtaposed and each crystal axis whose sign is changed are also optically and mechanically equivalent to each other (equivalent). In the present invention When it is necessary to define the relative orientation of the crystal axis strictly, for example, the crystal axis [〇11] and the optically equivalent crystal axes such as [(ΗΠΜΟ-ηρπΗ)] ^ are changed with symbols and arranged positions (list ) °, but S, when it is not necessary to define the relative orientation of the crystal axis strictly, use the table of the crystal axis [011] as a general expression like [011], [0-Π], [no] Most optically equivalent crystal axes. The same as the crystal axis [_ or [m], etc., the same for crystal axes other than crystal rod u]. When an optical system with high resolution is required, a crystal lens , Cast Wu crystal axis _], crystal axis [〇11] 'or crystal axis [⑴] and optical axis _

Binding

• 17-

584898 A7 ____B7 Fifth, the description of the invention (^ ~) is about the same. This is because the rotational symmetry of the optical axis of birefringence can be optimally set by making these crystal axes coincide with the optical axis. In addition, when the crystal axis is aligned with the Z axis, the Z axis is in a plane (XY plane) perpendicular to the crystal axis [100], [010], [11〇], [-110], or the like. When the crystal axis [〇11] is made to coincide with the Z axis, the crystal axis [100], [· 100], [〇1, etc.] exist in the XY plane. In addition, when the crystallographic axis [ill] is consistent with the z-axis, there are crystallographic axes [1-10], [11-2], etc. in the \ ¥ plane. Therefore, even if the Z axis is made to coincide with any one of the three crystal axes [001], [011], [111] described above, there is still a degree of freedom to rotate the center of the optical axis by what angle the crystal lens is required to rotate. The effect of birefringence changes with its rotation angle. In the first embodiment, the crystal axes [00] and the optical axis a X of the projection optical system 10 are aligned with the crystal lenses 105 and 106 '. In addition, in the crystal lenses 109 and 11, the crystal axis [丨 丨 丨] is aligned with the optical axis AX100 of the projection optical system 100. Fig. 4 is a diagram illustrating the definition of a rotation angle around the optical axis of a crystal lens. Furthermore, in Fig. 4 (a), (b), (c), the + z axis is the direction from the front side of the paper toward itself, and is the same as the optical axis AX of the projection optical system 100. As shown in tf in Fig. 4 (a), for the crystal lens Gj (the lens of the crystal lens 105 and 〇6f) whose crystal axis [〇〇1] is consistent with the optical axis (ζ axis), it is necessary to determine from the XY plane The rotation amount (rotation angle) in the χ pumping direction toward the γ-axis direction from the Z-axis of the crystal axis [100] within the rotation center is pj. In addition, as shown in FIG. 4 (b), for a crystalline lens Gj (i lens of the crystalline lenses 10 and 11) whose crystal axis [m] coincides with the optical axis (axis), -18 · is required. This paper size applies to China National Standard (CNS) A4 (210X 297mm) ---- A7 B7

584898 V. Description of the invention (Determine the amount of rotation (rotation angle) from the X-axis direction with the Z-axis of the crystal axis [1 · 1G] in the XY plane as the rotation center to the Z-axis direction. Furthermore, although This embodiment is not used, but for a crystal lens whose crystal axis [011] and the optical axis (ζ axis) coincide ... 'As shown in FIG. 4 (c), it is necessary to determine the crystal axis [100] from its XY plane. The amount of rotation (rotation angle) from the silk direction of the 2-axis 4 rotation center to the Y-axis direction is: Fig. 5 illustrates the angle Θ formed by the imaging light in the crystal lens Gj and the ❻ direction and the angle 0 formed by the X-axis direction. Definition diagram. That is, FIG. 5 shows the imaging light pattern diameter (105 m, 106 m, 109 m, " 〇⑷) in the crystalline lens Gj (the crystalline lens 105, 106, 10, 11). The angle θ formed with the ❻ direction and the angle formed with the X-axis direction are 0. The vector in FIG. 5 is parallel to the imaging light pattern diameter (ι05㈤ m, H) 9 m, 110 m in each crystal lens Gj · Direction vector so that its starting point coincides with z, the point above the axis I. Furthermore, Z, the axis system moves the z-axis of the optical axis parallel to the starting point I of the vector Ljm The axis of the position is, of course, equal to the direction of the z-axis. At this time, the vectors Ljm and Z are defined, and the angle formed by the axis direction is θ. For the j-th crystal lens Gj, the angle is θ ″. In addition, the vector is defined The end point P is projected on Z, the position above the axis is the origin 〇, the line segment extending from the origin θ to the end point P and X, the axis forms an angle of 0. At this time; for the j-th crystal lens Gj ' This angle is also 0j. Here, χ, the axis is also parallel to the X axis, and its direction is of course equal to the direction of the axis. As a result, the p axis is also parallel to the Y axis, and its direction is of course equal to the direction of the γ axis.

Hereinafter, the polarized light having an electric scene in a plane containing a vector indicating the direction of travel of the light beam and the I-axis is referred to as "R polarized light", and contains a direction toward B -19-

Binding

584898 A7 B7 V. Description of the invention (

LjmiL and the polarized plane of R are polarized in the plane where there is an electrical scene is called "0 polarized light". More broadly, the R-polarized light system means polarized light whose polarization direction is approximately the same as the diameter direction of a circle centered on AX 100. The θ polarized light indicates polarized light whose polarization direction is approximately the same as the circumferential direction of a circle centered at A X 100. Based on the above premise, the expression "calculating the above-mentioned birefringence amount" is explained again. The expression "evaluation effect on the birefringence amount of the light beam in the j-th crystal lens Gj" represents the amount of variation in the curvature of r polarized light. The evaluation amount Rj (the first evaluation amount) and the evaluation amount Sj (the second evaluation amount) indicating the variation in the tortuosity of the θ polarized light. The two evaluation quantities Rj • and Sj • are obtained by using the physical property constant α of the crystal forming the crystal lens Gj, the light pattern diameter L j of each light beam in the crystal lens Gj, and the three angles 0 j, 0 j, and pj described above. , And the angle parameter ω j (= 0 j -pj), through the analysis of the inventors of this case, we can understand that it can be expressed by the following formula. That is, in the crystal lens (crystal optical element) Gj where the optical axis and the crystal axis [1 1 1] are set to be consistent, the first evaluation amount Rj and the second evaluation amount Sj can be expressed by the following formula (1) and (2) are shown separately. Formula 5

Rj = axLjx [56x {l-c〇s (40j)} -32 / " 2xsin (4 0j) xsin (3 6jj)] / 192 (1)

Sj = a xLjx [32x {l-cos (20j)} + 64 / " 2xsin (2 Θ j) xsin (3 ω 『)] / 192 (2) Furthermore, the optical axis and the crystal axis [001] are Set the crystalline lens (crystalline optical element) Gj to be consistent, the first evaluation amount Rj and the second evaluation amount -20- This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) 584898 A7 B7

5. Description of the invention (

Sj can be expressed by the following formulas (3) and (4), respectively.

Rj = ^ xLjx {l-c〇s (4 6 > j)} x {-84-12xcos (46; j)} / 192 (3)

Sj = a xLjx {l-cos (2 0j)} x {-48 + 48xcos (4a) j)} / 192 (4) In addition, 'the optical axis and the crystal axis [Oil] are set to the same crystal lens (crystal Optical element) Gj, the first evaluation amount Rj and the second evaluation amount Sj can be expressed by the following formulas (5) and (6), respectively.

Rj = a xLjx [{l.c〇s (4 0j)} x {21-9xcos (4 ^) j) -84xcos (26; j)} + 96xcos (2 ^ j)] / 192 (5)

Sj = ^ xLjx [{l-cos (2 (9j)} x {12 + 36xcos (46Jj) + 48xcos (26L) j)} -96xcos (26; j)] / 192 (6) Crystal property constant a, Represents the birefringence of light traveling in the direction of the crystal axis [〇il], the refractive index η 100 of light having a polarization direction (the direction of the electric field) in the direction of the crystal axis [100], and 〇-11] has a difference in refractive index η〇11 of the light in the polarization direction (the direction of the electric field). The physical constant a, if it is crystalline fluorite, is about 3 · 6 × 107 for ArF laser light with a wavelength of 93 nm, and about 6 · 5 × 10 · 7 for F2 laser light with a wavelength of 157 nm. The light pattern diameter length Lj is the length of the imaging light pattern diameter in the crystal lens Gj (length such as the light pattern diameter of 105 m). Furthermore, since the term cos is included, the term of sin is a unitless quantity, and the evaluation quantities Rj and Sj represent changes in the light pattern diameter and length of the transmitted light according to the birefringence (light pattern diameter and length information). In this way, there are many (four in this embodiment) crystalline lenses Gj above the imaging light 100 m from 1 point on the optical network 1 1 to 1 point on the wafer 102, so for Most of the crystalline lenses Gj each -21-This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 public attack)

Binding

584898

Don't owe uf h I Rj and s j. Then, the sum τ of the ^ th evaluation quantity ((Σ4 represents the cumulative accumulation sign for different j) and the sum of the second evaluation quantity ˜ ~, which is the sum of the second evaluation quantity sj. The total evaluation amount and Σ S j are indicators indicating the influence of the birefringence on the entire projection optical system 100m of the imaging light beam 100m (change in the light pattern diameter and length of the transmitted light according to the birefringence). That is, if the value of the total evaluation amount sRj is equal to the value of the total evaluation amount, the light pattern diameter and length changes of R polarized light and ytterbium polarized light are equal, and therefore, the wavefronts also become the same. More specifically, since the crystal lens 105 and 106 are aligned with the crystal axis [001] and the optical axis AX100, the diameter of the imaging light pattern is 105 m and 106 m. Lj and the above-mentioned angle ej, and by substituting those data into the expressions (3) and (4), the evaluation quantities Rj and Sj of each of the crystal lenses 105, 106 are obtained. In addition, regarding the crystal lens 10,9, since the crystal axis [111] and the optical axis AX 100 are aligned, the optical pattern diameter length y and The above-mentioned angles ㊀ ′ and 0 j ′ are obtained by substituting those data into the expressions (丨) and (2) to obtain the evaluation amounts Rj & Sj of each of the crystal lenses 109 and 110, respectively. Then, the total evaluation amounts ZRj and ZSj regarding the total of the evaluation amounts Rj and sj for all the crystalline lenses 1 05, 106, 109, and 11 are obtained. The wavefront aberration in the imaging beam (100L ~ 100R) from 1 point on the optical network 101 to 1 point on the wafer 102 is to determine the optical pattern diameter length between the imaging rays In this case, it is necessary to obtain SRj and sSj for each imaging ray (by imaging ray at different positions on the pupil plane PP). And ZRj and Σ S j are fixed for all the imaging rays respectively, and if Σ rj and ς S j _____- 22 ^ ___ This paper size uses the Chinese National Standard (CNS) A4 specification (210 X 297 male father) 584898

For all of the I-rays being equal to each other, there is no wavefront aberration in the image beam (iOOl ~ 100R). Then, the relationship that 2Rj and sSj are fixed for all imaging rays and Σ Rj and Σ Sj are equal to each other for all imaging rays is satisfied, and the design of the projection optical system 100 is optimized, that is, By optimizing the thickness, radius of curvature, interval, etc. of each lens, and optimizing the rotation angle around the optical axis of the crystal lens, an optical system without wavefront aberration due to birefringence can be realized . Furthermore, it is difficult to completely fix sRj and ESj to all the imaging rays, and to make sRj and ssj completely equal to each other. In fact, by controlling the error ranges of ΣM and 2Sj to less than 1/2 of the exposure wavelength λ, an optical system that does not accept the adverse effects of birefringence can be practically realized. In other words, the absolute value of the difference between Σ Rj and a certain value and the absolute value of the difference between Σ Sj and a sufficient value are used to control the light ratio in the imaging beam focused on at least an arbitrary i point on the image surface or on the object surface. λ / 2 is small, and the absolute value of the difference from sSj is used to control the light ratio of the imaging beam focused on at least any of the 丨 points on the image surface or the surface of the object; I / 2 is small to achieve An optical system that does not substantially accept the adverse effects of birefringence. But 疋 'assumes this standard value; I / 2 is a pattern with a degree of fineness of k 1 factor = 0.35 (line width = k 1 X λ / Ν A), so as not to greatly affect the imaging characteristics When the size of the exposure pattern is smaller, stricter standards are necessary. For example, when using a phase-shifting optical network and exposing a pattern with a degree of fineness of k 丨 factor = 0 · 2, the errors of Σ Rj and Σ sj will not be mistaken. 23- This paper applies the Chinese National Standard (CNS) A4 specification ( 210X297 mm)-584898 A7 _____B7 V. Description of the invention (21) If the difference range is controlled to less than 1/20 of the exposure wavelength λ for all imaging rays, it becomes difficult to obtain good imaging characteristics. However, it is generally related to the whole surface of the imaging beam (the entire surface of the pupil plane ρ ρ), and it is difficult to realize the R polarized light and theta polarized light as described above. However, if a part of each imaging beam (part of the pupil plane PP) is considered separately, such R polarized light and Θ polarized light are polarized light that is combined with the rotation ranks as a transformation relationship for the real X polarized light and the gamma polarized light. Therefore, it is assumed that the R polarized light and theta polarized light have no wavefront aberration in this polarized state, and the real X polarized light combined with the relationship between its polarized state and rotation ranks, and there is no wavefront aberration for the Y polarized light beam. As described above, there is no particular problem in using an optical system using an evaluation index based on R polarization and 0 polarization. However, in the above formulas (1) to (6), the term including c0j (= 0 j-pj), that is, the existence of the term including 0j, means that the angle formed by the light beam and the X-axis direction is formed. ' The effect of birefringence varies. That is, the values of these terms can be changed by changing the angle pj in the angle parameter ω j, that is, the rotation angle of the crystal lens G j in a certain axial direction. In a crystal lens with the crystal axis [1 1 1] as the optical axis, since Rj and Sj have terms proportional to s i η (3 coj), there are three rotationally symmetrical values for the rotation of the lens. This means that the amount of change in the light pattern diameter given to Rj and Sj fluctuates periodically with 120 degrees of lens rotation. Therefore, if two crystal lenses with the crystal axis [1 11] as the optical axis are used, the lens on one side and the lens on the other side only rotate relative to the optical axis by 60 degrees or 180 degrees (== 60 + 120). If the crystal axes [1- 10] on both sides are set in the XY plane only at 60 or 180 degrees, the 3 rotation-symmetric components of the two lenses will be eliminated. -24-_ This paper is suitable for the Chinese national standard (CNS ) A4 specifications (21 × 297 male H " · 584898 A7 ______B7 V. Description of the invention (22) pin, it is convenient to know that SRj and Σ Sj are made equal for each imaging beam. Similarly, the crystal axis [00 1 ] Is a crystal lens with an optical axis. Since Rj and Sj have terms proportional to cos (400j), there are 4 times of rotational symmetry for the rotation of the lens. In this case, Rj and Sj are 90 times the lens rotation. The degree is changed by the period. Therefore, if two crystal lenses with the crystal axis [〇〇1] as the optical axis are used, the lens on the other side is only 45 degrees or 135 degrees with the optical axis as the center (= 45 degrees) +90) Relative rotation, set the crystal axis of both sides in the XY plane [100] is only 45 degrees or 1 If the angles are separated at 35 degrees, 'the 4th rotational symmetry components of the two lenses are cancelled out, and it is convenient to know that ZRj and ZSj are made equal for each imaging beam. Furthermore,' the crystal axis [〇1 1] is the optical axis. , Because Rj and Sj have two sides of a term proportional to cos (4c0j) and a term proportional to Cos (2〇) j). In this case, use 4 crystal lenses with the crystal axis [0 11] as the optical axis, and set each lens to rotate relative to the optical axis at 45 degrees relative to each other. If each crystal axis [100] in the XY plane is set to be 45 degrees away from each other The rotational asymmetric component of each lens is cancelled, and it is convenient to know that Σ Rj and Σ Sj are made equal for each imaging beam. Of course, the rotation-symmetric component cancellation of the two lens pairs or the rotation non-common cancellation of the four lens pairs is not limited to the two lens or four lens application. Therefore, while adjusting the rotation angle, thickness, radius of curvature, interval, etc. around the optical axis of most crystal lenses, it is not necessary to set the global SRj and ΣSj to be equal. __- 25 ^ _____ This paper size applies to China National Standard (CNS) A4 (210 X 297)

For example, using three lenses having approximately the same thickness with the crystal axis [111] as the optical axis can also counteract the rotationally asymmetric component of birefringence. In this case, it is 120 degrees as described above in a cycle in which the rotation of one lens is asymmetric. Therefore, the three lenses have a relationship of rotation positions separated by 40 degrees from each other with the optical axis as the center, that is, by setting the direction of the crystal axis [U 〇] perpendicular to the plane with the optical axis as the center, The relationship between the rotation positions separated by 40 degrees from the ground causes the rotation asymmetry of the three lenses to be shifted from each other by 1/3 cycles and overlap each other. At this time, for the three lenses, the direction of the crystal axis [丨 _ 丨 〇] of the first lens has the direction of the crystal axis [1 -1 〇] of the second lens with the optical axis as the center in a certain direction. There is only a 40 degree rotation relationship. The direction of the crystal axis [1 -10] of the third lens has only 4 with the optical axis as the center in the same certain direction with respect to the direction of the crystal axis [1 _ 1 〇] of the second lens. The relationship of 〇 degree rotation. In other words, the rotation angle of the crystal axis [1-10] of each lens is 0 °, 40 °, and 80 ° based on the lens of one of the three lenses (= 0 °). When the refractive power of each of the three lenses is weak and the direction of light flux in each lens is approximately constant, the sin (3〇) j) of the above formulas (丨) and (2), for three lenses The lenses are represented by the following formulas (21), (22), respectively. Here, the unit of the parameter of s i η is degree. sin (3〇〇l) (21) sin {3 (col + 40)} = sin (3col + 120) (22) sin (3 (col + 80)) = sin (3col + 240) (23) and , Can formula (22) and (23), such as the following formulas (22,) and -26- This paper size applies Chinese National Standard (CNS) A4 specifications (210X297 mm) 584898 A7 B7 V. Description of the invention (24) (23 is rewritten as shown. Sin (3 〇〇1x 1) x cos (120) + cos (3 ω 1) x sin (120) (22 ') sin (3c〇lxl) xcos (240) + cos (3c〇l) xsin (240) (23,) Therefore, the sum of the expressions (21), (22), and (23) is expressed by the following expression (24). {l + cos (120) + cos (240)} X sin (3 ω 1) + {sin (120) + sin (240)} X c〇s (3 ω 1) (24) In the formula (24), l + cos (120) + cos (240) and sin (l20) + sin (24〇) are both 0. Therefore, the sum of the expressions (21), (22), and (23), that is, the value of (24) becomes 0. In other words, By setting the rotation position relationship of three lenses with the crystal axis [1 1 1] as the optical axis, and the optical axis as the center separated by 40 degrees from each other, the rotationally asymmetric component of birefringence is removed due to its offsetting ability. Then 'even with this three lens group, It is convenient to make 2Rj and ZSj equal for each imaging beam. Similarly, using three lenses with approximately the same thickness with the crystal axis [00 1] as the optical axis can also counteract the rotationally asymmetric refraction. Component. In this case, the period of asymmetric rotation with one lens is 90 degrees as described above. Therefore, there is a relationship between the rotation positions of three lenses separated by 30 degrees from each other with the optical axis as the center. That is, by setting the direction perpendicular to the crystal axis [100] in the plane as the center of the optical axis. With the relationship of rotation positions separated by 30 degrees from each other, the rotation asymmetry of the three lenses becomes 1/3 each. Periods are staggered and overlap each other. In the above formulas (3) and (4), cos (4c0j) is represented by the following formulas (31), (32), and (33) for three lenses. Here, the paper size of the parameters of cos applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 584898 A7 B7 V. Description of the invention (25) The unit is degree. Cos (4 ^ 1) (31) cos {4 (6〇1 + 30)} = cos (46; 1 + 120) (32) cos {4〇1 + 60)} = cos (4o 1 + 240) (33) Furthermore, it is possible to change Promoter (32) and (33), as in the following equation (32) and (33 *) is rewritten as shown. cos (46J l) xcos (120) -sin (46; l) xsin (120) (32 ') cos (46J l) xcos (240) -sin (4 (jj l) xsin (240) (33') Therefore The sum of equations (31), (32), and (33) is represented by the following equation (34): {1 + cos (120) + cos (240)} xcos (46j l)-{sin (120 ) + sin (240)} xcos (46J 1) (34) In equation (34), l + cos (120) + cos (240) and sin (120) + sin (240) are both 0. Therefore, for The sum of the expressions (31), (32), and (33), that is, the value of (34) becomes 0. In other words, by setting three lenses with the crystal axis [00 1] as the optical axis, the optical axis is set. The rotation position relationship of the centers being 30 degrees apart from each other can remove the rotationally asymmetric component of birefringence due to its offsetting effect. Then, even with such three lens groups, it is also known that iRj and ESj are made equal for each imaging beam. For the sake of convenience, the method for reducing the i-symmetric asymmetric birefringence of the lens with the crystal axis [111] as the optical axis and the three lenses with the crystal axis [00 1] as the optical axis is not limited to The offset of the rotationally asymmetric components of the two lenses or the three lenses that are mutually rotating is canceled. If the method is further developed, when the crystal lens has a rotation asymmetry of / 3 degrees, by using rotations with (β / Q) degrees separated from each other with the optical axis as the center-28- This paper is applicable to China National Standard (CNS) A4 (210 X297 mm)

Binding

584898 A7 B7

The positional relationship of the Q lens (any integer greater than Q 疋 2) of the crystalline lens can remove the birefringent asymmetric components due to its offsetting effect. In other words, when using M lenses (M is an integer of 3 or more) whose crystal axis [111] is the optical axis, the lenses having the M lens are set to each other with the optical axis as the center. The rotation position relationship separated by (120 / M) degrees is enough to remove the rotational asymmetric component of birefringence due to its offsetting effect. Specifically, for example, when using five crystalline lenses with the crystal axis [1 i 1] as the optical axis, the lens having five lenses is set to each other with the optical axis as the center 24 (= 120/5). The rotational position relationship separated by degrees can offset the rotational asymmetric component of birefringence. In addition, when using a N lens (N is an arbitrary integer of 3 or more) with a crystal axis [00] as the optical axis, the lenses having the N lens are set to each other with the optical axis as the center. (90 / N) degrees of rotation position relationship, due to its offset effect to remove the rotational asymmetric component of birefringence. Specifically, "for example, when using six crystalline lenses whose crystal axis [001] is the optical axis", the lens having six lenses is set at 15 (= 90/6) degrees apart from each other with the optical axis as the center. The rotational position relationship can offset the rotational asymmetric component of birefringence. In addition, the rotation angle of each crystal lens may be the same as the above-mentioned embodiment, as long as it is possible to add a rotationally asymmetric periodic stone to the above-mentioned values (20 / μ, 90 / N). In general, although the number of lenses with a rotationally asymmetric component to counteract birefringence may be two, the method described above uses an arbitrary number of lenses of three or more to offset the rotational non-refractive index. Symmetrical components, so when the lens number of 2 pieces is given to the lens set _ -29- This paper size applies Chinese National Standard (CNS) Α4 specifications (210X297)

Binding

584898 A7 B7

V. Description of the invention (It is convenient to reduce the number of restrictions. In other words, when Σ Rj and Σ Sj are made equal for each imaging beam, a lens group made of such a large number of crystalline lenses can be used. As described above, 'Although the refraction power of each lens is weak and the traveling direction of the light beam in each lens is approximately constant, the above-mentioned offsetting effect is best obtained, but it is inevitable that the above-mentioned offsetting effect can be obtained at other times However, when using the lens with the crystal axis [0 1 1] as the optical axis, as shown in the above equations (5) and (6), as the term of rotational asymmetry, there is a term proportional to cosHoj). And a term proportional to cos (2c〇j). Among the two terms, the term proportional to cos (2c〇j) is a component having a 180-degree rotation period. Therefore, as described above, by arranging two lenses of approximately the same thickness with the crystal axis [〇11] as the optical axis, rotating the optical axis centers by 90 degrees (rotating the two lens groups at 90 degrees), Offset the rotational asymmetric component. In addition, from the same study, the use of three lenses having approximately the same thickness with the crystal axis [0 11] as the optical axis can also offset the rotational asymmetric component. At this time, the three lenses have a rotational position relationship of 60 degrees apart from each other with the optical axis as the center, that is, by setting (rotating three lens groups at 60 degrees) the crystal axis in a plane perpendicular to the optical axis [ The direction of 100] has a rotational position relationship of 60 degrees apart from each other around the optical axis, and can offset the rotational asymmetric component. More generally, a lens with a rotation asymmetrical proportion proportional to cos (2c〇j) is set to use an L-piece (where L is an arbitrary integer of 3 or more) with the crystal axis [011] as the optical axis. It is sufficient for the L lens to have a rotational position relationship separated from each other (1 80 / L) degrees around the optical axis. If according to this method, the lens with the crystal axis [011] as the optical axis can be selected for -30- This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) 584898 A7 B7 V. Description of the invention (28 offsets the number of lenses with a rotational asymmetry proportional to Cos (2〇) j) is the value of any tone, which makes the design of the lens less restrictive and more convenient. In addition, the rotational asymmetry term proportional to cos (4ω j) is the same as a lens with the crystal axis as the optical axis, and can be offset by using two lenses that rotate around 45 places with the optical axis as the center. Furthermore, from the same research as above, the use of three lenses having approximately the same thickness with the crystal axis [011] as the optical axis can also offset the rotational asymmetric component. At this time, the three lenses have a rotational position relationship of 30 degrees apart from each other around the optical axis, that is, by setting (30 degree rotation of the three lens groups) the crystal axis in a plane perpendicular to the optical axis [ι The direction of 〇〇] has a rotational position relationship of 30 degrees apart from each other with the optical axis as the center, and can offset the rotational asymmetric component. More generally, a lens having a p-piece (P is an arbitrary integer of 2 or more) with a crystal axis [〇1 1] as an optical axis is removed after removing the rotational asymmetry term proportional to cos (4c〇j). It is sufficient that the lens of the P lens has a rotation position relationship separated from each other (90 / P) degrees around the optical axis. If according to this method, the lens with the crystal axis [0 1 1] as the optical axis, the number of lenses that can be selected to offset the rotational asymmetry term proportional to C0s (4c〇j) is arbitrary. Value, it is more convenient to design the lens with fewer restrictions. In addition, when the crystal axis [011] is used as the optical axis, in order to actually offset the rotational asymmetric component proportional to COS (2c〇j), at least the p group is prepared to be described adjacently along the optical axis. Lens group consisting of L lens or 2 lenses. Then, by giving a relative rotation with the optical axis as the center between each lens group, it is ideal to remove the term proportional to cos (400j). Even in this method, it is not limited to Cancel the spinner standard (CNS) A4 specification (21C) X297 Gongguang which is proportional to cos (4 (〇j) --- 584898

A7 _______ B7 Description of the Invention (29 ^) ^ The lens group of the asymmetric term is two groups, and three or more lens groups can also be used, so there are fewer restrictions on lens design and it is more convenient. Furthermore, in this embodiment, although the number of lenses of the rotationally asymmetric component for offsetting birefringence may be two, in the above-mentioned method, since an arbitrary number of lenses of three or more is used, it is better than The case where the number of lenses is two is satisfactory because there are few restrictions on lens design. As described above, the effect of birefringence is removed by rotation around the optical axis of the lens of the plurality of lenses, and the rotation direction of each lens of the plurality of lenses is preferably controlled within ± 4 degrees with respect to the predetermined angle. If the setting error of the rotation angle becomes larger than the allowable value, the cancellation effect of the complex refraction of the present invention is reduced, and further, the imaging performance is deteriorated due to the complex refraction, which causes a problem. In addition, it is also desirable to control the direction error of the optical axis of a specified crystal axis that should be approximately the same as the optical axis within about 4 degrees. If the setting errors of the specified crystal axis and optical axis angles are larger than the allowable values, as in the case described above, there is a problem that the imaging performance is deteriorated due to the residual birefringence. This is the same regardless of the case where the birefringence is removed using a crystalline lens made of three or more lenses or the case where the birefringence is removed using a crystalline lens made of two lenses. However, the angular error range within ± 4 degrees is the same as the above-mentioned standard. It is a permissible angular error when a subtle pattern (pattern width == k 1 X λ / Ν A) of ^ factor = 〇35 is assumed. For an optical system in which it is necessary to write a finer pattern than this, it is necessary to reduce the above-mentioned angular error range of the crystal axis and the optical axis specified above. For example, using a phase-shifting optical network, the exposure u factor = about 0.2 is fine -32-This paper size is applicable to China National Standard (CNS) A4 specifications (210X297mm D

Binding

Line 584898

For slight patterns, it is best to misalign these angles to less than 2 degrees. P p already

Conversely, if a pattern with a factor of about kl = 0.5 is used as the optical system, even if these angle errors are relaxed to ± 6 degrees, practically, sufficient imaging performance can be obtained. Furthermore, in order to strictly control the direction of the crystal axis, in the manufacturing process of the crystalline material of the material of the crystalline lens and the processing (grinding, grinding, etc.) of the crystalline lens, the crystal having a constant wavelength close to the lattice of the crystal is乂 Light irradiates the crystal, and it is necessary to measure the meandering pattern to confirm the direction of the crystal axis, that is, the direction of the crystal axis is satisfactory. Binding

In addition, as described above, when the lens group having the same crystal axis as the optical axis is relative to the center of the rotating optical axis, those rotational asymmetric components are eliminated to eliminate the offset. The. In the subsection affects ERj and ESj. ⑴ When the optical axis and the crystal axis [111] are set to be the same crystalline lens, only when there is no influence of the term of ω j, the evaluation value R ″ of the first one and the evaluation value Sj of the second one are less than The expressions (7) and (8) of the columns are respectively expressed.

Rj '= a > < Ljx56x {l-cos (40j)} / 192 ⑺

Sjf = axLjx32x {lc〇s (29j)} / 192 ⑻ In addition, when the optical axis and the crystal axis [〇〇 丨] are set to be the same as the crystalline lens Gj, only when the item excluding 〇; is not affected, The first evaluation amount Rj · and the second evaluation amount sj 'are expressed by the following formulas (9) and (丨 0), respectively.

Rj, == a xLjx-84x {l-cos (49j)} / 192 ⑼

Sj — cl xLjx-48x {l-cos (20j)} / 192 (i〇) ______ 33- This paper is suitable for financial standards @ National standard (CNS) A4 specifications (2ι〇X 29? Public love j- 584898 A7 ______ B7_ V. Description of the invention (31) Furthermore, when the optical axis and the crystal axis [011] are set to be the same as the crystal lens Gj, and there is no influence of the term ω j, the first evaluation amount Rj, and The second evaluation value Sj is shown in the following formulas (11) and (12), respectively. Table 7J >

Rj-a xLjx21x {l-c〇s (40j)} / 192 (11)

Sj, == a xLjxl2x {lc〇s (20j)} / 192 (12) As mentioned above, regardless of which crystal axis is the optical axis, the coefficient of the {l-cos (4ej)} term in Rj There is a 7: 4 relationship between the coefficients and the coefficients containing the terms of {l-cos (2ej)} in Sj. In addition, between the crystal lens whose crystal axis [111] is the optical axis, the crystal lens whose crystal axis [001] is the optical axis, and the crystal lens whose crystal axis [〇1 1] is the optical axis, regardless of the value of Rj, and sj Any one of the values of, holds a relationship of 8: -12: 3. Therefore, when the lens group with the same crystal axis as the optical axis is relative to the center of the rotating optical axis to offset those rotational asymmetric components, the optical pattern in the lens group with the crystal axis [111] as the optical axis is longer. The sum 丨 丨 丨, the crystal axis [00 1] is the sum of the light pattern diameter in the crystal lens with the optical axis sLO〇1, and the crystal axis [0 11] is the sum of the light pattern diameter and length in the crystal lens with the optical axis Σ When L 〇11 satisfies the relationship shown in the following formula (13), £ Rj and ZSj can be regarded as 0 together. 8xiL111.12xzL001 + 3xEL011 = 〇 (13) In the case of the first embodiment of the projection optical system 100, the crystal lens (105, 106) including the crystal axis [001] is the optical axis, and the crystal axis [111] is the optical axis Crystal lens (109,110), and crystal lens without crystal axis [〇 丨 丨] is the optical axis. Therefore, the crystalline lens 105 and the crystalline lens 丨 06 are regarded as approximately mutual --------- -34-____ This paper size applies to the Chinese National Standard (CNS) A4 specification (210X 297 cm) 584898 A7 B7 V. Description of the invention (32) The thicknesses are equal, and the lenses of both sides are rotated by 45 degrees or 135 degrees with respect to the center of the optical axis. In addition, the crystal lens 109 and the crystal lens 11 are regarded as approximately equal in thickness to each other, and the lenses of both lenses are rotated by only 60 degrees or 180 degrees with respect to the center of the optical axis. Then, the rotational asymmetrical component of birefringence between the crystal lens (105, 106) whose crystal axis [001] is the optical axis and the crystal lens (109, 11) whose crystal axis [111] is the optical axis is canceled. At this time, between the sum of the light pattern diameters of the imaging light pattern diameters of 0.05 m and 106 m, and the sum of the light pattern diameters of the imaging light pattern diameters of 109 m and 110 m, sL 111, the following formula is satisfied: In the relationship shown in (14), ΣK ″ and Σ s ″ can be regarded as 0 together. 8xiL111.12xiL001 = 0 (14) That is, 'the ratio of the sum of the thicknesses of the crystal lenses 10 and 105 to the sum of the thicknesses of the crystal lenses 109 and 110 can be set to approximately 2: 3, which can greatly reduce the complex The effect of refraction. Furthermore, in the above example, for each imaging light beam in the imaging light beam, ERj and [Sj are all equal to 0. However, it is not always necessary to make SRj and ESj coincide with 0, and it is sufficient to make Σ R j and Σ S j approximately equal to a certain value for each imaging ray. Therefore, the errors of Σ Rj and Σ Sj centered on a certain value are, as described above, for example, controlled in the range of λ / 2 or λ / 20. By setting the crystal axis of each crystal lens, the rotation angle pj , The thickness of all lenses, the radius of curvature, the interval, etc., can achieve an optical system that significantly suppresses the adverse effects of birefringence. In addition, as in the first embodiment described above, the Chinese paper standard (CNS) A4 standard (CNS) A4 specification (in accordance with the Chinese National Standard (CNS) A4) is adopted to eliminate the birefringence in the entire optical system by the combination of lens groups that offset the respective rotational asymmetry. 210X297 father)-Binding

584898 A7 B7

The method of good influence 'is just one example of the method of reducing the bad influence of birefringence in the present invention. That is, it is not limited to the combination of the above-mentioned rotating lens group. In the entire optical system, as long as it is set to the first total evaluation amount SRj and the second total evaluation amount Σ Sj for focusing on the image surface or object If any one point on the surface becomes equal, of course, any other method is also possible. Fig. 6 is a diagram schematically showing a configuration of a projection optical system according to a second embodiment of the present invention. In the second embodiment, the present invention is applicable to a refraction-type projection optical system whose F2 laser having a wavelength of 157 nm is optimized for aberration correction. In the projection optical system 200 (corresponding to the projection optical system 300 of FIG. 1) of the second embodiment, a light beam emitted from a point on the optical network 2101 (corresponding to the optical network 1 0 1 of FIG. 1) passes along The lens 204 arranged on the optical axis AX 2 〇a enters the mirror region 203, which is a means for changing the diameter of the light pattern, and enters the light beam refracted by the plane mirror 2 0a at the mirror region 2 0. The lenses 205 and 206 on which the axis AX200b is arranged enter the concave mirror 220. The light beam refracted by the concave mirror 220 passes through the lenses 206 and 205 and then enters the mirror region 203. The light beam refracted by the plane mirror 203b in the mirror region 203 is condensed at one point on the wafer 202 (f corresponds to the wafer 102 of FIG. 1) through lenses 207 to 212 arranged along the optical axis AX200a. In this way, a projection image of a pattern drawn on the optical network 201 is formed on the wafer 202. In the second embodiment, all of the lenses 204 to 212 are formed of vaporized homogeneous crystals (Lawstone). Even in such a refracting and refraction optical system, the present invention can be bound with the paper standard of China National Standards (CNS) A4 (210X297 public attack).

584898 A7 ______ B7___ V. Summary of the invention (34 ~) ^ Evaluates the effect of the birefringence of the optical series 200 based on the total evaluations SRj and sSj. Based on the evaluations Σ Rj and Σ Sj according to the present invention, the complex of the projection optical system 200 can be controlled The adverse effects of refraction are minimal. However, in the case of the reflection-refraction-type projection optical system of the second embodiment, if a part of the crystal lens is arranged on an optical axis different from that of other crystal lenses, the plane reflection mirrors 203a, 203b, and concave reflection are used. The reflection effect of the mirror 220 also changes the direction of the X-axis, which is the reference of the rotation angle around the optical axis of each crystal lens, and the path of the imaging light pattern of the crystal lens 205,206 is the same as the first. The situation of each embodiment is different. Hereinafter, the setting of the XYZ axis of the reflection-refractive projection optical system 2000 will be described. First, as shown in Fig. 6, a crystal lens 204 arranged along the optical axis AX200a near the optical network 201 is provided with a system for setting X 0Y 0Z 0 coordinates, as in the first embodiment. That is, a direction in which the optical axis AX200a along the traveling direction of the exposure light rays is set to the + Z0 axis downwards, and a direction to the right in the horizontal direction on the paper in FIG. 6 is set to the + X0 axis, in the drawing in FIG. 6 Front-facing direction + γ-axis direction. At this time, the X0Υ0Z0 coordinate system is the right-hand rule. In this way, for the crystal lens 204, the above-mentioned angles θ j, pj, and 0 j are calculated using the X0Χ0Z0 coordinate system as a reference, and those values are substituted into equations (1) to (6) to calculate the evaluation amounts Rj and Sj. . --- Secondly, after the imaging beam is reflected by the plane mirror 203a, the direction of the beam is to the right as shown in the figure, so the X1Y1Z1 coordinate system is set with the direction of the beam as the + Z 1 axis. At this time, the χΐγ1Z1 coordinate system is transformed into a left-handed coordinate system (hereinafter, referred to as a "left-handed system") by the reflection of the plane mirror 203a. That is, the right of the optical axis AX200b along the direction of the exposure light is set to +2 1 ----- z2Lz__ This paper size applies the Chinese National Standard (CISiS) A4 specification (210X297 mm) --- binding

584898 A7 B7 V. Description of the invention (The direction of the axis is the direction of + X1 axis downwards in the figure, and the direction of + Y 1 axis from the paper surface. Thus, for the right through the crystal lens 205, 206 The imaging beam can be calculated using the χ1γιζ1 coordinate system as the reference, and the angles 0j, pj, and 0j can be obtained and substituted into equations (1) and (6) to calculate the pricing amounts Rj and Sj. However, in this case The X1Y1Z1 coordinate system is a left-handed rule. It is necessary to pay attention to the method of taking the signs of the angles pj and 0 j in Figure 4 and Figure 5. That is, when using the left-handed rule of the XIY1Z1 coordinate system, the X axis, z axis, and The axis and the Z ′ axis are respectively the same as those in FIG. 4 and FIG. 5, the Υ axis and 轴, the axis becomes opposite to the direction of FIG. 4 and FIG. 5. Because the rotation angle pj and the angle 0j are defined from the X axis to the Y axis The direction of rotation is positive, so in the X1 Y 1Z 1 coordinate system of the left-hand rule, the positive direction of rotation also becomes opposite to that shown in Figure 4 and Figure 5. However, the direction of rotation from the XI axis to the Y1 axis Is exactly the same. Then, if the imaging beam is refracted by the concave mirror 220, because the beam The traveling direction of is the leftward direction in the figure, so set the X2Y2Z2 coordinate system with the traveling direction of the beam as + Z2 axis. At this time, the X2Y2Z2 coordinate system returns to the right-hand rule by the reflection of the concave mirror 220. That is, Set the leftward direction of the optical axis AX 200b along the traveling direction of the exposure light to the + Z2 axis direction, the upward direction in the figure to the + χ 2 axis direction, and the paper inward direction to the + Y 2 axis direction In this way, for the imaging beams that pass through the crystal lenses 205 and 206 to the left, using the X2Y2Z2 coordinate system as a reference, the above-mentioned angles 0j, pj, and 0j are obtained, and those values are substituted into equations (1) to (6), Calculate the evaluation values Rj and Sj. -38-This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 584898 A7 ______B7_ __ 5. Description of the invention (36) Furthermore, 'Because of the crystal lens 2〇 5, 206, to make the crystal axis [〇〇 or crystal axis [Π1], [011]) consistent with the direction of travel of the beam, so in the crystal lens 205,206 when the beam is traveling to the right and to the left, It is necessary to note that the sign of each crystal axis is opposite. That is, when the light beam is traveling to the right, the crystal axis is [1 11], and when it is leftward, it is treated as the crystal axis [-1-1-1]. Similarly, the crystal axis [100] is treated as the crystal axis [-100], and the crystal axis [1-10] is treated as the crystal axis [110]. Finally, because the imaging beam is refracted by the plane mirror 2031), the traveling direction of the beam returns to the downward direction in the figure, so the X3Υ3Z3 coordinate system is set with the traveling direction of the beam as the + Z3 axis. At this time, the X3Υ3Z3 coordinate system is transformed into the left-hand rule by the reflection effect of the plane mirror 20b. That is, 'the downward direction of the optical axis AX200a along the traveling direction of the exposure light is + Z3 axis direction, the right direction in the figure is + X 3 axis direction, and the paper inward direction is + γ 3 axis direction. In this way, for the crystal lenses 207 to 212, the angles θ j, pj, and 0 j are calculated based on the X3Y3Z3 coordinate system, and those values are substituted into equations (J) to (6) 'to calculate the evaluation amount Rj. And sj. Furthermore, because the X3Y3Z3 coordinate system is a left-handed rule, the angles pj and 0 j are calculated in the same way as when transmitting the light beams of the crystal lenses 20.5, 20.6 to the right. The total evaluation ERj and ZSj obtained by adding the evaluation amounts Rj and Sj of the respective crystal lenses obtained in this way can be used as an index of the influence of the birefringence in the reflection-refraction type projection optical system 200. The same applies to the reflective projection optical series 100 of the first embodiment. In addition, starting from the 1 point on the optical network 20 1 and converging to the 1 point on the wafer 2 02 -39-This paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 public attack)-584898 A7 _______ B7 V. Description of the Invention (37) All the imaging rays of the light beam are centered on a certain value of the total evaluation quantities Σ R ″ and Σ s ″, for example, the error is controlled in the range of / 2 or person / 2. Setting the crystal axis of each crystal lens, the rotation angle p ", the thickness of all lenses, the radius of curvature, and the" interval, "etc., can achieve the effect of suppressing the adverse effects of birefringence to an extremely small optical system. It is also related to the first embodiment. The same is true for the reflective projection optical series 100. Furthermore, in the projection optical system 200 according to the second embodiment, the crystal lens 205 and 206 arranged near the concave reflecting mirror 220 is set to "make the crystal axis of fluorite [11 丨] It is aligned with the optical axis AX200b, and the crystal axis [1-10] is arranged to rotate only 60 degrees or 180 degrees with respect to the center of the optical axis. In addition, for the crystal lenses 204, 207, 208, and 209, the crystal axis [011] of the fluorite is aligned with the optical axis AX200a, and the crystal axis [100] is arranged at 45 degrees apart from the optical axis as a center and is relatively rotated. The crystal lenses 2 11, 2 12 are arranged so that the crystal axis [00 1] of fluorite is aligned with the optical axis AX200a, and the directions of the crystal axis [丨 00] are aligned. Then, for the crystal lens 210, the crystal axis [00 丨] of fluorite and the optical axis AX200a are aligned so that the direction of the crystal axis [100] is only relative to the optical axis of the crystal lens 2 1 1, 2 12 The center is rotated by 45 degrees or 135 degrees. In this way, it becomes easy to set the total evaluation amounts XRj and SSj for all imaging rays emitted from one point on the optical network 201 and converged to one point on the wafer 202. Furthermore, in the above-mentioned first and second embodiments, in order to simplify the description of the present invention, only the imaging beam emitted from one point on the optical network 1 〇1 (201) is focused on. . However, in order to obtain good image formation, -40- this paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) " — " 584898

Yes, for the imaging beam from the entire point in the effective illumination area on the optical network 101 (201) to the effective exposure area on the wafer 102 (202), of course, the above-mentioned relationship of the present invention should be satisfied. In addition, in each of the above embodiments, although calcium fluoride crystal (fluorite) is used as the birefringent optical material, it is not limited to this, and other uniaxial crystals such as barium fluoride crystals can also be used. (BaF2), lithium fluoride crystal (LiF), sodium fluoride crystal (NaF), fluoride gill crystal, beryllium fluoride crystal (BeFO and other crystalline materials that are transparent to ultraviolet rays. In this case, barium fluoride crystals exceed Crystal materials with a diameter of 200 mm have also been developed and are promising as lens materials. At this time, it is desirable that the orientation of the crystal axis of barium fluoride (B a FJ, etc.) is also determined according to the present invention. Furthermore, in the above-mentioned Although the present invention is applicable to a projection optical system in each embodiment, the present invention is not limited to this. For the purpose of projecting an inspection optical system, for example, the present invention can also be applied to an optical system for aberration measurement. The type of the optical system to which the present invention is applied is different from the optical system that forms an image from the object surface to the image surface as described in the above embodiment. The optical system from the object surface to the pupil surface also has an effective The structure of an optical system that directs a parallel beam toward the image plane. At this time, although the implementation is as described above, the point from the 1 point on the optical network 101 (2101) to the wafer 102 (202) The imaging beam at 1 point cannot exist, but by using this imaging beam as the imaging beam from the 1 point on the surface of the object to the pupil surface, or the imaging beam condensed at 1 point on the image plane, It is obvious that the present invention can also be applied to the above-mentioned embodiments. The exposure apparatus of each of the above-mentioned embodiments is illuminated by an illuminating device -_______ ~ 41-This paper standard _ China National Tomb Standard (CNS) A4 Specification (210X297 Public Attack 5-- 584898 A7 B7 V. Description of the Invention (39) (Lighting Engineering) Optical Screen (Mask), by exposing (copying process) the pattern used for engraving formed on the mask using a projection optical system to Photosensitive substrates can be used to manufacture microdevices (semiconductor elements, imaging elements, liquid crystal display elements, thin-film magnetic heads, etc.) In the following, a certain circuit pattern is formed by using the exposure device of each embodiment as a wafer of a photosensitive substrate. An example of a method for a semiconductor device of a microdevice is described with reference to the flowchart of FIG. 7. First, in step 301 of FIG. 7, the metal film is evaporated on the wafer of the batch. In the next step 302, in one batch of A photoresist is applied on the metal film on the wafer. Then, in step 303, the exposure device of each embodiment is used, and the images of the pattern on the mask are sequentially exposed through the projection optical system and transcribed in one batch. Each injection area on the wafer. Then, in step 304, the photoresist on one batch of wafers is developed, and then in step 305, the resist pattern is used as a mask on the wafers of the batch. Etching is performed, and the injection patterns corresponding to the circuit pattern on the mask are formed on each wafer. After that, elements such as a semiconductor element are manufactured by forming a circuit pattern at a higher level or the like. According to the above-mentioned method for manufacturing a semiconductor device, a semiconductor device having a high processing capability and an extremely fine circuit pattern can be obtained. In addition, although in step 301 to step 305, the metal is evaporated on the wafer, the photoresist is applied on the metal film, and then exposed to develop each process of the method, but before these processes After the silicon oxide film is formed on the wafer, a resist is applied on the silicon oxide film, and then each step such as exposure, development, and etching can be performed.

584898 A7 ____B7 _ V. Description of the invention (4Q ~) — doubt. In addition, in the exposure apparatus of each embodiment, by forming a fixed pattern (circuit pattern, electrode pattern, etc.) on a flat plate (glass substrate), a liquid crystal display element can be obtained as a microdevice. Hereinafter, an example of the method at this time will be described with reference to the flowchart of FIG. 8. In Fig. 8, the pattern forming step 401 uses the exposure apparatus of each embodiment to expose the patterned cavities of the mask to a photosensitive substrate (such as a glass substrate to which an anti-name agent is applied), and performs a so-called photolithography step. Through this photolithography process, a fixed pattern including a large number of electrodes on a photosensitive substrate is formed. After that, the exposed substrate is subjected to various processes such as a development process, an etching process process, and an optical screen peeling process to form a fixed pattern on the substrate. Then, the process proceeds to the next color filter formation process 402. Next, in color In the filter forming step 402, a group of three points corresponding to R (Red), G (Green), and B (Blue) is arranged in a matrix, and the three stripes of R, G, and B are arranged. The filter groups are arranged in the direction of a plurality of horizontal scanning lines, and then, after the color filter forming step 402, a component assembly process 403 is performed. In the element mounting step 403, a liquid crystal panel (liquid crystal element) is assembled using a substrate having a predetermined pattern obtained in the pattern forming step 401, and a color filter obtained in the color filter forming step. In the element assembling step 403, for example, liquid crystal is injected between a substrate having a certain pattern obtained in the pattern forming step 401 and the color filter forming step 402 to the color> light filter to manufacture a liquid crystal liquid crystal panel. (Liquid crystal element). After that, in the module assembly project 404, install the assembled LCD panel ____- 43 -___ This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 584898 A7 B7 V. Description of the invention (( The liquid crystal display element is used as a liquid crystal display element for display circuits such as backlights. If the above-mentioned liquid crystal display element manufacturing method is used, a liquid crystal display element with high processing capacity and extremely fine circuit patterns can be obtained. In the above embodiments, the present invention is applied to a projection optical system mounted on an exposure device, but the present invention is not limited to this, and the present invention can also be applied to other general optical systems. Each embodiment uses an ArF quasi-knife laser light source that provides light with a wavelength of 193 nm and a ρ2 laser light source that provides light with a wavelength of 157 nm, but is not limited to this. For example, a wavelength of 126 nm can be used. Ar laser light source of light, etc. As explained above, in the present invention, for example, even if the birefringence of fluorite is used Crystal materials can also achieve optical systems with good optical performance that are virtually unaffected by birefringence. Therefore, by incorporating the optical system of the present invention into an exposure device, and by using a high-resolution projection optical system, Accurate exposure projection can produce a good microdevice. Brief description of FIG. 1 is a diagram schematically showing a configuration of an exposure apparatus equipped with a projection optical system according to each embodiment of the present invention. FIG. 2 is a diagram roughly showing The structure of the projection optical system according to the first embodiment of the present invention. Fig. 3 is a diagram illustrating the names of the crystal axes of crystals such as cubic crystals of fluorite, etc. — — _ -44-Paper size Applicable to family standard (CNS) A4 specification (210X297)

Binding

584898 A7 B7 V. Explanation of the invention (42 Figures 4 (a) ~ (c) are diagrams explaining the definition of the rotation angle centered on the optical axis of the crystal lens. Figure 5 illustrates the imaging light and the z-axis direction of the crystal lens Gj Definition of the angle Θ and the angle 0 with respect to the X-axis direction. Fig. 6 is a diagram showing a configuration of a projection optical system according to a second embodiment of the present invention® 'Fig. 7 is obtained as a microdevice Flow chart of the method of the conductive element at the time. Figure 8 is a time chart from the time of the liquid crystal display element as a micro device. Explanation of the flow symbols of the sub method 1 light source 2 light transmission system 3 lighting optical system 5 optical network Stage 8 Wafer Stage 6, 9 Boxes 10 Positioning Microscope 100, 200, 300 Projection Optical System 101, 201 Optical Network 102, 202 Wafer 103 ~ 110 Crystal Lens 203 Mirror Area 2 2 0 Concave Mirror 204 ~ 212 Crystal Lens

Binding

-45-

Claims (1)

584898 Brother No. 091111285 patent application Chinese patent application replacement scope (February 1993) 6. Application for patents ^ ___ —, ~-, β.ΐιτ -χ- I Lian, Yue Ling means I _ i 1. An optical system including a crystalline optical element formed by crystals belonging to a cubic crystal system, wherein most of the crystalline optical elements include: the first crystal axis and the optical axis of the optical system are roughly A crystalline optical element set in a consistent manner, and a crystalline optical element set in a manner in which a second crystalline axis different from the first crystalline axis described above and the optical axis are approximately the same, the majority of the crystalline optical elements Gj described above, The direction of a certain crystal axis in a plane orthogonal to the optical axis is arranged with respect to the direction of the certain axis in the plane by rotating the optical axis around the optical axis by an angle ⑸. For a specific light beam, an angle formed by the specific light beam and the direction of the optical axis is taken as an angle, and an angle formed by the specific light beam and the fixed axis direction is taken as 0 j When the optical path length of the specific light ray is Lj, the physical property constant α from the crystal, a crystal axis approximately consistent with the optical axis, the angle P j, the angle θ j, the angle, and the optical path are defined. The first evaluation amount Rj of the first constant polarized light determined by the length Lj and the second evaluation amount Sj of the second constant polarized light, and the first evaluation amount of the above-mentioned most crystalline optical elements The first sum evaluation value SRj of the sum of Rj and the second sum evaluation value Σ Sj of the sum of the second evaluation quantities Sj of the above-mentioned most crystalline optical elements are for the image book condensed on the optical system. Paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 584898-" 丨 丨 I, VI. The light rays in the imaging beam on at least any i point on the surface of the patent application or on the surface of the object have a certain relationship. 2. The optical system according to item i of the scope of patent application, wherein the first evaluation amount Rj is information on the change in the optical path length of the first predetermined polarized light, and the second evaluation amount sj is the information for the second Information on the change in the optical path length of a certain polarized light. 3. The optical system according to item 1 or 2 of the scope of patent application, wherein the above-mentioned certain relationship includes: at least the sum of the i-th evaluation value Rj is at least concentrated on the image surface or the object surface of the optical system The rays in the imaging beam at any i point are approximately equal, and the above-mentioned second total evaluation value Σ Sj is for rays in the imaging beam focused on at least any one point on the image surface or the object surface of the optical system. Are approximately equal to each other, and the sum of the above-mentioned first evaluation amount Rj and the above-mentioned second total evaluation amount ESj are mutually equal for imaging light rays focused on at least any one point on the image surface or the object surface of the optical system Approximately equal relationship. 4_ The optical system according to item 1 or 2 of the scope of the patent application, wherein the crystalline optical element Gj is set to approximately the same as the optical axis and the crystal axis [111] or a crystal axis that is optically equivalent to the crystal axis. In the above, when the specific crystal axis is a crystal axis [-11〇] or a crystal axis which is optically equivalent to the crystal axis, and ωj = 0 j -pj, the first evaluation value Rj and the second Each evaluation value Sj is expressed by the following formula, Rj = a > < Ljx [56x {l-cos (4 0j)} -32 ^ 2xsin (4 0 j) xsin (3 6〇j)] / 192- 2-This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) Gutter 584898 A8 B8 C8 D8 VI. Application scope Sj = axLjx [32x {l-cos (2 0j)} + 64 / " 2xsin (2 0j) xsin (3 ω] ·)] / 192. 5. The optical system according to item 1 or 2 of the scope of the patent application, in which the optical axis and the crystal axis [0 01] or the crystal axis which is optically equivalent to the crystal axis are set to approximately the same crystal optical element In Gj, when the specific crystal axis is a crystal axis [110] or an optically equivalent crystal axis, and ω j = 0 j-pj, the first evaluation value Rj and the second Each evaluation value Sj is expressed by the following formula, Rj = a xLjx {l-cos (4 0 j)} x {-84-12xcos (46jj)} / 192 Sj = a xLjx {l-cos (2 (0j) } x {-48 + 48xcos (4oj)} / 192. 6. The optical system according to item 1 or 2 of the scope of the patent application, wherein the optical axis and the crystal axis [011] are optically aligned with the crystal axis, etc. When the effective crystal axis is set to approximately the same crystal optical element Gj, the specific crystal axis is the crystal axis [100] or an optically equivalent crystal axis, when ωj = 0 j-pj The above-mentioned first evaluation amount Rj and the above-mentioned second evaluation amount Sj are respectively expressed by the following formulas: Rj = a xLjx [{l-cos (4 (9j)} x {21-9xcos (46L) j) -84xcos (26jj)} + 96xcos (2〇j)] / 192 Sj = a xLjx [{l-cos (2 0j)} x {12 + 36xcos (46L) j) + 48xcos (26; j)} -96xcos (2oj)] / 192. 7. The optical system according to item 1 or 2 of the scope of the patent application, wherein the physical property constant a of the crystal is the crystal axis [011] or optically with the crystal axis in the crystal forming each crystal optical element Gj. Among the light traveling in the direction of the equivalent crystal axis, the crystal axis [100] or the same as the crystal axis -3- This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 584898 A8 The refractive index of the light having a polarization direction in the direction of the optically equivalent crystal axis is equal to the rate η 100. It is the same as the crystallographic axis [〇_ 丨 丨] or the ~ w axis of the crystallographic axis. The refractive index η 〇 丄 of the light having the direction of polarization is different. 8. According to the optical system of item 1 or 2 of the patent application, where the wavelength field of light is set to X, the absolute value of the difference between the first total evaluation value Σ Rj and the second total evaluation value, The light rays in the imaging beam focused on at least any point on the image surface or the object surface of the optical system are set smaller than λ / 2. 9. The optical system according to item 1 or 2 of the scope of patent application, in which when the wavelength field of light is set as λ, the absolute value of the difference between the above-mentioned first sum evaluation blade R j and a specific value is used for condensing light at The light in the imaging beam of at least any point on the image surface or the object surface of the optical system is set smaller than λ / 2. 10. According to the optical system of the scope of the patent application, when the wavelength of light is taken as λ, the absolute value of the difference between the above-mentioned second sum evaluation value Σ sj and a specific value is for the light condensed on the optical system. The light rays in the imaging beam of at least any i point on the image surface or on the object surface are set smaller than λ / 2. 11. An optical system comprising a plurality of crystalline optical elements formed by crystals belonging to a cubic crystal system, characterized in that it contains the optical axis and crystal axis [丨 丨 丨] described above, or crystals that are optically equivalent to the crystal axis The crystalline optical elements of Μ (M is an integer of 3 or more) set in a manner that the axis is approximately the same, -4-This paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) 584898 A8 B8 C8 __ _ D8 6. The scope of the patent application and the crystalline optical element of the above-mentioned M sheet has a crystalline axis [1 -10] in a plane perpendicular to the optical axis, or a direction that is optically equivalent to the crystalline axis of the crystalline axis. The optical axis is a rotational positional relationship in which the centers are separated from each other by approximately (120 / M) degrees. 12. The optical system according to item 11 of the scope of patent application, which further includes the above-mentioned optical axis and crystal axis [〇〇1], or N that is set in a manner that is approximately consistent with the crystal axis that is optically equivalent. (N is an integer of 3 or more) a crystalline optical element of the sheet, and the crystalline optical element of the N sheet has a crystalline axis [100] in a plane perpendicular to the optical axis or is optically aligned with the crystalline axis, etc. The directions of the effective crystal axes are rotationally related to each other by approximately (90 / N) degrees from the optical axis as a center. 13. The optical system according to item 11 or 2 of the scope of the patent application, which further includes the above optical axis and crystal axis [0 11] or is set in a manner approximately consistent with the crystal axis which is optically equivalent to the crystal axis A crystalline optical element of L (L is an integer of 3 or more), and the crystalline optical element of the L sheet has a crystalline axis [100] in a plane perpendicular to the optical axis or is optically aligned with the crystalline axis The directions of the equivalent crystallographic axes are rotationally related to each other by about (180 / L) degrees with the optical axis as a center. 14. The optical system according to item 11 or 2 of the scope of the patent application, which further includes the optical axis and the crystal axis [011] described above or is set in a manner that is approximately consistent with the crystal axis that is optically equivalent. Crystalline optical element of p (p is an integer of 2 or more), -5- This paper size applies Chinese National Standard (CNS) A4 specification (210X297 mm) 584898 A8 B8 C8 D8 χ, the scope of patent application and the above-mentioned p film The crystalline optical element has a crystalline axis [100] in a plane perpendicular to the optical axis or a direction that is optically equivalent to the crystalline axis of the crystalline axis. The optical axis is used as a center to be approximately separated from each other (90 / P) Degree of rotation position relationship. 15. An optical system comprising a plurality of crystalline optical elements formed by crystals belonging to a cubic crystal series, characterized in that the optical axis and the crystal axis [00 1] are included or are optically equivalent to the crystal axis The crystalline optical element of N (N is an integer of 3 or more) pieces set in a manner that the crystalline axis is approximately the same, and the crystalline optical element of the N piece has a crystalline axis [100] in a plane perpendicular to the optical axis or It is a rotational positional relationship that is approximately optically equivalent to the direction of the crystal axis of the crystal axis with respect to the optical axis as a center (90 / N) degrees apart from each other. 16. The optical system according to item 15 of the scope of patent application, which further includes the above-mentioned optical axis and crystal axis [011] or L (set in a manner that is approximately the same as the crystal axis optically equivalent crystal axis) L is an integer of 3 or more), and the crystalline optical element of the L sheet has a crystal axis [100] in a plane perpendicular to the optical axis or a crystal equivalent to the crystal axis optically equivalent The directions of the axes are rotationally related to each other at approximately (180 / L) degrees with the optical axis as a center. 17. The optical system according to item 15 or 16 of the scope of patent application, which further includes the above-mentioned optical axis and crystal axis [011] or is set in a manner that is approximately consistent with the crystal axis that is optically equivalent. P (P is a whole number of 2 or more-6) This paper size applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 584898 A8 B8 C8 D8 Number of patent application scopes, and the above P The crystalline optical element of the sheet has a crystalline axis [100] in a plane perpendicular to the optical axis or a direction in which the crystalline axis is optically equivalent to the crystalline axis, and is separated from each other approximately with the optical axis as a center. (90 / P) degree rotation position relationship. 18. · An optical system comprising a plurality of crystalline optical elements formed by crystals belonging to a cubic crystal series, characterized in that the optical axis and the crystal axis [01 丨] are included or are optically equivalent to the crystal axis The crystalline optical element of the L (l is an integer of 3 or more) sheet set in such a manner that the crystalline axis is approximately uniform, and the crystalline optical element of the L sheet has a crystalline axis [100] in a plane perpendicular to the optical axis. ] Or a rotation position relationship in which the direction of the crystal axis which is optically equivalent to the crystal axis is approximately 180 ° / L apart from each other with the optical axis as a center. 19. The optical system according to item 8 of the scope of the patent application, which further includes the above-mentioned optical axis and crystal axis [〇11] or P (P Is an integer of 2 or more), and the crystalline optical element of the P sheet has a crystalline axis [100] in a plane perpendicular to the optical axis or an optically equivalent crystalline axis The directions of rotation are about (90 / P) degrees apart from each other around the optical axis as a center. 20. The optical system according to any one of claims 1, 2, 11, 12, 15, 16, 18, or 19, wherein the crystal is a fluorinated grape. The paper size of the crystal is applicable to Chinese national standards ( CNS) A4 size (210 X 297 mm) Binding 584898 A8 B8 C8 D8 Sixth, the scope of patent application or crystallization of gasification lock. 21 · An exposure device comprising an illumination system for illuminating a photomask, and any one of claims 1 to 20 of a patent application range for forming a pattern formed on the photomask on a photosensitive substrate Optical system. 22 · A method for manufacturing a microdevice, comprising an exposure step of exposing the pattern of the photomask to the photosensitive substrate by using an exposure device according to item 21 of the patent application scope, and an exposure step of exposing the photosensitive substrate through the exposure step. The developing step of developing the photosensitive substrate. -8-