JP2006078553A - Objective optical system, aberration measuring device and exposure apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an objective optical system capable of satisfactorily correcting aberration even when the objective optical system is, for example, such a type that a pinhole member is disposed on the position closest to the object side and a large numerical aperture is secured. <P>SOLUTION: The objective optical system is provided with a first optical member (L11:11a) which is disposed on the position closest to the object side and is formed of a prescribed pattern on the surface of the object side. Further, the objective optical system is provided with a first lens group (G1) having the first optical member of positive refractive power, a second lens group (G2) having at least two positive lenses, a third lens group (G3) having at least one positive lens and a fourth lens group (G4) having at least one negative lens in order from the object side. The surface of the image side of the first optical member is formed in a prescribed curved shape. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an objective optical system, an aberration measuring apparatus, and an exposure apparatus, and more particularly to an objective optical system suitable for an apparatus for measuring wavefront aberration of a projection optical system mounted on the exposure apparatus.

  For example, a projection optical system mounted on an exposure apparatus used when manufacturing a microdevice such as a semiconductor element or a liquid crystal display element in a photolithography process has a very small residual aberration in order to realize high resolution. Is required. Therefore, when manufacturing the exposure apparatus, the wavefront aberration of the projection optical system is measured using a predetermined wavefront measuring apparatus, and the projection optical system is optically adjusted based on the measurement result.

In this case, in the objective optical system used in this type of wavefront measuring apparatus, a pinhole member made of a plane parallel plate having a pinhole formed on the object side surface is disposed on the most object side (projection optical system side). (See, for example, Patent Document 1).
JP 2002-169083 A

  In the conventional objective optical system as described above, when the numerical aperture is relatively small, the amount of aberration generated on the back surface (image side surface) of the pinhole member is small, and the aberration is sufficiently corrected in the subsequent lens group. Can do. However, for example, in a projection optical system for a semiconductor exposure apparatus, the numerical aperture tends to increase due to the miniaturization of the projection pattern, and it is necessary to ensure a large numerical aperture in the objective optical system for an aberration measuring apparatus.

  In a conventional objective optical system, for example, if a light beam having a large incident angle corresponding to a numerical aperture of 0.9 or more is incident, the amount of aberration generated on the back surface of the pinhole member becomes too large, and the subsequent lens There was an inconvenience that aberrations could not be completely corrected depending on the group. Actually, when the pinhole member is made of quartz, the emission angle of the light beam corresponding to the numerical aperture 0.65 on the back surface of the pinhole member is about 40 degrees, but corresponds to the numerical aperture 0.95. The exit angle of the light beam on the back surface of the pinhole member exceeds 70 degrees.

  In addition, in a conventional objective optical system, if the subsequent lens group forcibly corrects aberrations that have occurred greatly on the back surface of the pinhole member due to light rays corresponding to a large numerical aperture, the entire optical system becomes large. There has been a disadvantage that the power of each lens is increased as a whole, and the required manufacturing accuracy and assembly accuracy become severe.

  The present invention has been made in view of the above-mentioned problems. For example, the pinhole member is disposed on the most object side, and aberrations are corrected well despite a large numerical aperture. An object of the present invention is to provide an objective optical system.

  Also provided is an aberration measuring apparatus that can measure, for example, the wavefront aberration of a projection optical system for an exposure apparatus with high accuracy by using an objective optical system that has a large numerical aperture and whose aberration is well corrected. With the goal.

  In addition, exposure that can perform good projection exposure with high accuracy through a projection optical system that is optically adjusted with high accuracy using an aberration measuring device that can measure wavefront aberration of the projection optical system with high accuracy An object is to provide an apparatus.

In order to solve the above problems, in the first embodiment of the present invention, in an objective optical system including a first optical member that is disposed closest to the object side and has a predetermined pattern formed on the object side surface,
An object optical system is provided in which an image side surface of the first optical member is formed in a predetermined curved surface shape.

In the second embodiment of the present invention, in the aberration measuring apparatus for measuring the wavefront aberration of the imaging optical system,
The object side surface of the first optical member includes a first form of objective optical system positioned on the image plane of the imaging optical system,
The aberration measuring apparatus is characterized in that the predetermined pattern formed on the object-side surface of the first optical member is a pinhole.

In the third embodiment of the present invention, in an exposure apparatus that exposes a pattern on a mask onto a photosensitive substrate via a projection optical system,
An exposure apparatus comprising a second form of aberration measuring apparatus for measuring the wavefront aberration of the projection optical system is provided.

  An objective optical system according to a typical aspect of the present invention includes a first optical member that is disposed closest to the object side and has a predetermined pattern such as a pinhole formed on a surface on the object side. The first optical member The image-side surface is a refracting surface and is formed in a curved surface with a convex surface facing the image side. With this configuration, the light incident on the object-side surface of the first optical member at a large incident angle corresponding to a large numerical aperture is refracted inward by the action of the image-side surface of the first optical member, and the subsequent lens It is possible to suppress the incident angle of the light beam to the group and to easily correct the aberration correction by the subsequent lens group.

  That is, in the present invention, it is possible to realize an objective optical system in which, for example, a pinhole member is arranged on the most object side, and aberrations are well corrected despite a large numerical aperture. it can. As a result, the present invention uses an objective optical system having a large numerical aperture and a well-corrected aberration, for example, aberration measurement capable of measuring the wavefront aberration of a projection optical system for an exposure apparatus with high accuracy. An apparatus can be realized. Further, in the exposure apparatus of the present invention, high-accuracy and good projection can be performed via the projection optical system that is optically adjusted with high accuracy using an aberration measuring apparatus that can measure the wavefront aberration of the projection optical system with high accuracy. Exposure can be performed, and as a result, a favorable device can be manufactured with high accuracy.

  The objective optical system of the present invention includes a first optical member that is disposed closest to the object side and has a predetermined pattern such as a pinhole formed on the object side surface. The image-side surface of the first optical member is formed in a predetermined curved surface shape. Specifically, the image-side surface of the first optical member is a refracting surface, and is formed in a curved surface with a convex surface facing the image side.

  With this configuration, the light incident on the object-side surface of the first optical member at a large incident angle corresponding to a large numerical aperture is refracted inward by the action of the image-side surface of the first optical member, and the subsequent lens It is possible to suppress the incident angle of the light beam to the group and to easily correct the aberration correction by the subsequent lens group. That is, in the present invention, it is possible to realize an objective optical system in which, for example, a pinhole member is arranged on the most object side, and aberrations are well corrected despite a large numerical aperture. it can.

  As a result, the present invention uses an objective optical system having a large numerical aperture and a well-corrected aberration, for example, aberration measurement capable of measuring the wavefront aberration of a projection optical system for an exposure apparatus with high accuracy. An apparatus can be realized. Further, in the exposure apparatus of the present invention, high-accuracy and good projection can be performed via the projection optical system that is optically adjusted with high accuracy using an aberration measuring apparatus that can measure the wavefront aberration of the projection optical system with high accuracy. Exposure can be performed.

  The objective optical system of the present invention includes, in order from the object side, a first lens group having a first optical member having a positive refractive power, a second lens group having at least two positive lenses, and at least one positive lens. It is preferable to include a third lens group having a fourth lens group having at least one negative lens. In this case, the second lens group can converge the light beam from the first lens group, and a desired magnification can be realized by appropriately setting the power ratio and the air interval between the third lens group and the fourth lens group. be able to.

In the present invention, it is preferable that the following conditional expression (1) is satisfied. In conditional expression (1), a is the maximum emission angle of the light beam from the image side surface of the first optical member, and NA is the numerical aperture of the objective optical system.
a / arcsin (NA) <0.95 (1)

  Conditional expression (1) defines an appropriate range for the power (refractive power) of the first lens group. If the upper limit of conditional expression (1) is exceeded, light rays will enter the subsequent lens group in a state where the amount of aberration generated on the image-side surface of the first optical member is large, which is disadvantageous for aberration correction. Therefore, it is not preferable.

  In the present invention, it is preferable that at least two optical members in the objective optical system are made of fluorite. In general, a change in refractive index occurs due to a change in environmental temperature, resulting in a change in optical performance (for example, defocus). By introducing fluorite, the direction of the refractive index change due to the temperature change is opposite to that of quartz. , Fluctuations in optical performance due to temperature changes can be kept small. Incidentally, while the refractive index of quartz increases with increasing temperature, the refractive index of fluorite decreases with increasing temperature.

  Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a drawing schematically showing a configuration of an exposure apparatus provided with an aberration measuring apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing an internal configuration of the aberration measuring apparatus according to the present embodiment. In FIG. 1, the Z axis is parallel to the optical axis AX of the projection optical system PL, the Y axis is parallel to the paper surface of FIG. 1 in the plane perpendicular to the optical axis AX, and the X axis is perpendicular to the paper surface of FIG. Are set respectively.

  Referring to FIG. 1, the exposure apparatus of this embodiment includes, for example, an ArF excimer laser light source or a KrF excimer laser light source as a light source 100 for supplying illumination light in the ultraviolet region. The light emitted from the light source 100 illuminates the reticle (mask) R on which a predetermined pattern is formed in a superimposed manner via the illumination optical system IL. When an ArF excimer laser light source is used as the light source 100, for example, the optical path between the light source 100 and the illumination optical system IL is sealed with a casing (not shown), and the most reticle side in the illumination optical system IL from the light source 100 is sealed. The space to the optical member is replaced with an inert gas such as helium gas or nitrogen, which is a gas having a low exposure light absorption rate, or is maintained in a substantially vacuum state.

  The reticle R is held parallel to the XY plane on the reticle stage RS via the reticle holder RH. A pattern to be transferred is formed on the reticle R, and a rectangular pattern region is illuminated. Reticle stage RS can be moved two-dimensionally along the reticle plane (ie, XY plane) by the action of a drive system (not shown), and its position coordinates are measured by interferometer RIF using reticle moving mirror RM. And the position is controlled. Light from the pattern formed on the reticle R forms a reticle pattern image on the wafer W, which is a photosensitive substrate, via the projection optical system PL.

  The wafer W is held parallel to the XY plane on the wafer stage WS via the wafer holder table WT. Then, a pattern image is formed in the rectangular still exposure region (effective exposure region) on the wafer W so as to optically correspond to the rectangular illumination region on the reticle R. The wafer stage WS can be moved two-dimensionally along the wafer surface (that is, the XY plane) by the action of a drive system (not shown), and its position coordinates are measured by an interferometer WIF using a wafer moving mirror WM. In addition, the position is controlled.

  For example, when an ArF excimer laser light source is used as the light source 100, the inside of the projection optical system PL is configured to be kept airtight, and the gas inside the projection optical system PL is replaced with an inert gas such as helium gas or nitrogen. Or kept in a vacuum. Further, a reticle R and a reticle stage RS are arranged in a narrow optical path between the illumination optical system IL and the projection optical system PL, but a casing (not shown) that hermetically surrounds the reticle R and the reticle stage RS. Is filled with an inert gas such as nitrogen or helium gas, or is kept in a vacuum state.

  In this way, collective exposure is performed using a drive system and an interferometer (RIF, WIF) or the like while two-dimensionally driving and controlling the wafer W in a plane (XY plane) orthogonal to the optical axis AX of the projection optical system PL. Thus, the pattern of the reticle R is sequentially exposed on the shot area of the wafer W in accordance with the so-called step-and-repeat method. Alternatively, the wafer W is moved according to a so-called step-and-scan method while moving the reticle R and the wafer W relative to the projection optical system PL in a plane (XY plane) orthogonal to the optical axis AX of the projection optical system PL. The reticle R pattern is scanned and exposed in each of the exposure regions.

  The exposure apparatus of this embodiment includes an aberration measuring apparatus 10 (not shown in FIG. 1) for measuring the wavefront aberration of the projection optical system PL as an imaging optical system. Referring to FIG. 2, in the aberration measuring apparatus 10 of the present embodiment, when measuring the wavefront aberration of the projection optical system PL that is a test optical system, a test mask TM for measuring aberration is installed on the reticle stage RS. In the test mask TM, a plurality of circular openings TMa for measuring aberration are two-dimensionally formed (for example, in a matrix along the X and Y directions).

  In addition, the aberration measuring apparatus 10 of the present embodiment has an objective composed of a pinhole member 11a and a subsequent lens group 11b mounted on the wafer stage WS at substantially the same height position (Z-direction position) as the exposure surface of the wafer W. An optical system 11 is provided. That is, the object side (projection optical system PL side) optical surface of the pinhole member 11a is positioned on the image plane of the projection optical system PL, and a pinhole 11aa is formed at the center of the optical surface. The pinhole 11aa is set larger than the image of the opening TMa of the test mask TM formed through the projection optical system PL.

  Here, when ArF excimer laser light having a wavelength of 193.3 nm is used as the exposure light, the objective optical system of the first embodiment described later is used as the objective optical system 11. In addition, when KrF excimer laser light having a wavelength of 248.3 nm is used as exposure light, the objective optical system of the second embodiment described later is used as the objective optical system 11. In the aberration measuring apparatus 10, light that has passed through one opening TMa of the test mask TM, the projection optical system PL, and the pinhole 11aa of the pinhole member 11a passes through the objective optical system 11 and an afocal relay lens (not shown). Then, the light enters the micro fly's eye lens (micro lens array) 12.

  The micro fly's eye lens 12 is arranged such that its incident surface is located at or near the position of the exit pupil of the objective optical system 11. The micro fly's eye lens 12 is an optical element configured by, for example, a large number of microlenses 12a having a square cross section and having positive refractive power arranged vertically and horizontally and densely. The micro fly's eye lens 12 is configured, for example, by performing etching processing on a parallel flat glass plate to form a micro lens group, and functions as a wavefront dividing element.

  Therefore, the light beam incident on the micro fly's eye lens 12 is two-dimensionally divided by a large number of microlenses 12a, and an image of one opening TMa is formed in the vicinity of the rear focal plane of each microlens 12a. The In other words, many images of the opening TMa are formed in the vicinity of the rear focal plane of the micro fly's eye lens 12. The images of the numerous openings TMa formed in this way are detected by the CCD 13 as a two-dimensional image sensor. The output of the CCD 13 is supplied to the signal processing unit 14.

  In the aberration measuring apparatus 10 of the present embodiment, the wavefront aberration of the projection optical system PL related to the position of the pinhole 11aa is measured based on the information related to the images of the many openings TMa supplied from the CCD 13 to the signal processing unit 14. Can do. Note that the detailed configuration and operation of the aberration measuring apparatus 10 excluding the objective optical system 11 can be referred to, for example, Japanese Patent Application Laid-Open No. 2002-169083. Hereinafter, the configuration and operation of the objective optical system 11 according to the present embodiment will be described.

  In each example of the present embodiment, the objective optical system includes, in order from the object side, a first lens group G1 having a pinhole member 11a as a first optical member having a positive refractive power and at least two positive lenses. The second lens group G2 includes a third lens group G3 having at least one positive lens, and a fourth lens group G4 having at least one negative lens. In addition, since the objective optical system of each embodiment is designed at infinity, an imaging lens (second objective lens) is arranged at an air interval of 70 mm on the image side of the objective optical system, and is connected to the objective optical system. A finite optical system is formed in combination with an image lens to evaluate the performance of the objective optical system.

[First embodiment]
FIG. 3 is a diagram schematically showing a lens configuration of the objective optical system according to the first example of the present embodiment. In the first embodiment, the present invention is applied to an objective optical system used for light having a wavelength of 193.3 nm. Referring to FIG. 3, in the objective optical system of the first example, the first lens group G1 is composed of a plano-convex lens L11 (that is, a pinhole member 11a) having a plane facing the object side. The second lens group G2 is composed of four positive meniscus lenses L21 to L24 having a concave surface directed toward the object side in order from the object side.

  The third lens group G3 includes, in order from the object side, a biconvex lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side. The fourth lens group G4 includes a biconcave lens L41. In the first example, the positive meniscus lenses L22 and L24 in the second lens group G2 and the biconvex lens L31 in the third lens group G3 are made of fluorite, and the other lenses are made of quartz. Here, the refractive index of quartz with respect to the wavelength used (λ = 193.3 nm) is 1.5603260, and the refractive index of fluorite is 1.5014550.

  The following table (1) lists the values of the specifications of the objective optical system according to the first example. In Table (1), NA represents the numerical aperture of the objective optical system, and Om represents the maximum object height. Furthermore, the surface number is the order of each surface from the object side, r is the radius of curvature (mm) of each surface, d is the spacing (mm) between the surfaces, and n is the wavelength used (λ = 193.3 nm). Refractive indexes are shown respectively.

(Table 1)
(Main specifications)
NA = 0.96
Om = 0.015mm

(Optical member specifications)
Surface number r dn optical member
1 ∞ 4.00000 1.5603260 (L11: 11a)
2 -70.03100 0.46016
3 -18.64990 4.00000 1.5603260 (L21)
4 -9.14100 0.30000
5 -21.04500 4.20000 1.5014550 (L22)
6 -10.21210 0.30000
7 -26.40900 4.30000 1.5603260 (L23)
8 -14.29050 0.30000
9 -45.29600 4.50000 1.5014550 (L24)
10 -20.22020 0.30000
11 470.51400 4.50000 1.5014550 (L31)
12 -38.13500 4.50000
13 27.60700 4.20000 1.5603260 (L32)
14 629.60000 10.00000
15 -19.41000 3.00000 1.5603260 (L41)
16 32.36900 70.00000

(Values for conditional expressions)
a = 64.9 degrees (1) a / arcsin (NA) = 0.927

  FIG. 4 is a diagram showing transverse aberration in the first example. As is apparent from the aberration diagram of FIG. 4, in the first example, although a large numerical aperture (NA = 0.96) is secured using ArF excimer laser light having a wavelength of 193.3 nm, It can be seen that the aberration is corrected well.

[Second Embodiment]
FIG. 5 is a diagram schematically showing a lens configuration of the objective optical system according to the second example of the present embodiment. In the second embodiment, the present invention is applied to an objective optical system used for light having a wavelength of 248.3 nm. Referring to FIG. 5, in the objective optical system of the second example, the first lens group G1 is composed of a plano-convex lens L11 (that is, a pinhole member 11a) having a plane facing the object side. The second lens group G2 is composed of four positive meniscus lenses L21 to L24 having a concave surface directed toward the object side in order from the object side.

  The third lens group G3 includes, in order from the object side, a biconvex lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side. The fourth lens group G4 includes a biconcave lens L41. In the second example, the positive meniscus lens L22 in the second lens group G2 and the biconvex lens L31 in the third lens group G3 are made of fluorite, and the other lenses are made of quartz. Here, the refractive index of quartz for the used wavelength (λ = 248.3 nm) is 1.5083897, and the refractive index of fluorite is 1.46778825.

  The following table (2) lists the values of the specifications of the objective optical system according to the second example. In Table (2), NA represents the numerical aperture of the objective optical system, and Om represents the maximum object height. Further, the surface number is the order of each surface from the object side, r is the radius of curvature (mm) of each surface, d is the space (mm) between the surfaces, and n is the wavelength used (λ = 248.3 nm). Refractive indexes are shown respectively.

(Table 2)
(Main specifications)
NA = 0.93
Om = 0.015mm

(Optical member specifications)
Surface number r dn optical member
1 ∞ 4.00000 1.5083897 (L11: 11a)
2 -70.03100 0.46065
3 -21.95100 4.00000 1.5083897 (L21)
4 -7.92000 0.30000
5 -19.95050 4.10000 1.4678825 (L22)
6 -9.60010 0.30000
7 -29.16100 4.20000 1.5083897 (L23)
8 -15.14960 0.30000
9 -37.07500 4.50000 1.5083897 (L24)
10 -20.04840 0.30000
11 250.25500 4.60000 1.4678825 (L31)
12 -30.78500 0.50000
13 29.37700 4.20000 1.5083897 (L32)
14 231.72800 12.00000
15 -17.43550 3.00000 1.5083897 (L41)
16 38.18800 70.00000

(Values for conditional expressions)
a = 61.3 degrees (1) a / arcsin (NA) = 0.943

  FIG. 6 is a diagram showing transverse aberration in the second example. As is apparent from the aberration diagram of FIG. 6, in the second example, although a large numerical aperture (NA = 0.93) is secured using KrF excimer laser light with a wavelength of 248.3 nm, It can be seen that the aberration is corrected well.

  Although not shown in the drawings, the imaging lens in each example includes a cemented lens of a biconvex lens L51 and a biconcave lens L52, a biconvex lens L53, and a biconcave lens L54 in order from the object side (objective optical system 11 side). And a plane parallel plate P1. The following table (3) lists the values of the specifications of the imaging lens in each example. In Table (3), the surface number is the order of each surface from the object side, r is the radius of curvature (mm) of each surface, d is the spacing (mm) between the surfaces, and n is the d line (λ = 587). .6 nm).

(Table 3)
Surface number r dn optical member
1 75.04300 5.10000 1.6228010 (L51)
2 -75.04300 2.00000 1.7495010 (L52)
3 1600.58000 7.50000
4 50.25600 5.10000 1.6675510 (L53)
5 -84.54100 1.80000 1.6126580 (L54)
6 36.91100 5.50000
7 ∞ 30.00000 1.5688290 (P1)
8 ∞

  In the above-described embodiment, the present invention is applied to an objective optical system including a first optical member (pinhole member) that is disposed closest to the object side and has a pinhole formed on the object side surface. Without being limited thereto, in general, the present invention can be applied to an objective optical system including a first optical member in which a predetermined pattern is formed on a surface on the object side. Specifically, for example, an objective optical system including a first optical member having an index formed on a surface on the object side, such as an objective optical system for an observation apparatus disclosed in Japanese Patent Laid-Open No. 2003-114381. The invention can also be applied.

  In the first embodiment described above, in the lenses L22, L24 and L31 formed from fluorite, for example, Japanese Patent Application Laid-Open No. 2003-50439 and corresponding thereto are used to correct the influence due to the intrinsic birefringence of fluorite. US Patent Publication No. 2003/0025894, International Patent Publication No. WO 03/007046 and corresponding US Patent Publication No. 2003/0011896, International Patent Publication No. WO 03/001271 and corresponding US Patent Publication No. 2003 / No. 0011893, International Patent Publication No. WO 03/003429 and the corresponding US Patent Publication No. 2003/0058421, or International Patent Publication No. WO 03/007045 and the corresponding US Patent Publication No. 2003/0053036. According to the technique shown, the relationship of crystal axis orientation of the fluorite are preferably positioned.

  In the exposure apparatus of the above-described embodiment, the reticle (mask) is illuminated by the illumination device (illumination process), and the transfer pattern formed on the mask is exposed to the photosensitive substrate using the projection optical system (exposure process). Thus, a micro device (semiconductor element, imaging element, liquid crystal display element, thin film magnetic head, etc.) can be manufactured. Hereinafter, referring to the flowchart of FIG. 7 for an example of a method for obtaining a semiconductor device as a micro device by forming a predetermined circuit pattern on a wafer or the like as a photosensitive substrate using the exposure apparatus of the present embodiment. I will explain.

  First, in step 301 of FIG. 7, a metal film is deposited on one lot of wafers. In the next step 302, a photoresist is applied on the metal film on the one lot of wafers. Thereafter, in step 303, using the exposure apparatus of the present embodiment, the image of the pattern on the mask is sequentially exposed and transferred to each shot area on the wafer of one lot via the projection optical system. Thereafter, in step 304, the photoresist on the one lot of wafers is developed, and in step 305, the resist pattern is etched on the one lot of wafers to form a pattern on the mask. Corresponding circuit patterns are formed in each shot area on each wafer.

  Thereafter, a device pattern such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer. According to the semiconductor device manufacturing method described above, a semiconductor device having an extremely fine circuit pattern can be obtained with high throughput. In steps 301 to 305, a metal is deposited on the wafer, a resist is applied on the metal film, and exposure, development, and etching processes are performed. Prior to these processes, on the wafer. It is needless to say that after forming a silicon oxide film, a resist may be applied on the silicon oxide film, and steps such as exposure, development, and etching may be performed.

  In the exposure apparatus of this embodiment, a liquid crystal display element as a micro device can be obtained by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate). Hereinafter, an example of the technique at this time will be described with reference to the flowchart of FIG. In FIG. 8, in the pattern formation process 401, a so-called photolithography process is performed in which the exposure pattern of the present embodiment is used to transfer and expose the mask pattern onto a photosensitive substrate (such as a glass substrate coated with a resist). By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. Thereafter, the exposed substrate undergoes steps such as a developing step, an etching step, and a resist stripping step, whereby a predetermined pattern is formed on the substrate, and the process proceeds to the next color filter forming step 402.

  Next, in the color filter forming step 402, a large number of sets of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix or three of R, G, and B A color filter is formed by arranging a plurality of stripe filter sets in the horizontal scanning line direction. Then, after the color filter forming step 402, a cell assembly step 403 is executed. In the cell assembly step 403, a liquid crystal panel (liquid crystal cell) is assembled using the substrate having the predetermined pattern obtained in the pattern formation step 401, the color filter obtained in the color filter formation step 402, and the like.

  In the cell assembly step 403, for example, liquid crystal is injected between the substrate having the predetermined pattern obtained in the pattern formation step 401 and the color filter obtained in the color filter formation step 402, and a liquid crystal panel (liquid crystal cell) is obtained. ). Thereafter, in a module assembling step 404, components such as an electric circuit and a backlight for performing a display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete a liquid crystal display element. According to the above-described method for manufacturing a liquid crystal display element, a liquid crystal display element having an extremely fine circuit pattern can be obtained with high throughput.

  In the above-described embodiment, an ArF excimer laser light source or a KrF excimer laser light source is used. However, the present invention is not limited to this, and other appropriate light sources can also be used. In the above-described embodiment, the present invention is applied to the objective optical system for an aberration measuring apparatus that measures the wavefront aberration of the projection optical system. However, the present invention is not limited to this, and the object optical system is arranged on the most object side. Another general objective optical system including a first optical member in which a predetermined pattern is formed on the object side surface, for example, an objective optical system of a measuring device that measures pupil transmittance distribution of an illumination optical system and a projection optical system, The present invention can be applied to the objective optical system of a measuring apparatus that measures the polarization distribution of the illumination optical system and the projection optical system.

  Further, the aberration measuring apparatus 10 of the above-described embodiment may be configured to be attachable to the wafer stage WS, or may be provided on a measurement stage different from the wafer stage. Further, in the above-described embodiment, the aberration measurement apparatus for the dry type exposure apparatus in which the gas is filled between the projection optical system PL and the wafer W as the substrate. However, the projection optical system PL and the wafer W (substrate) are used. It can also be applied to an immersion type exposure apparatus in which a liquid is filled in between.

  In the immersion type exposure apparatus, the numerical aperture on the substrate side of the projection optical system may exceed 1. However, in the aberration measuring apparatus including the objective optical system according to the present embodiment, the image of the first optical member having a predetermined pattern. Since the side surface is formed in a shape with the convex surface facing the image side, it is possible to capture all of the light beams having a numerical aperture exceeding 1.

  As the immersion type exposure apparatus, an immersion exposure apparatus that locally fills the liquid between the projection optical system PL and the substrate P, or a stage that holds the substrate to be exposed is moved in the liquid tank. The present invention can also be applied to an immersion exposure apparatus or an immersion exposure apparatus in which a liquid tank having a predetermined depth is formed on a stage and a substrate is held therein.

It is a figure which shows schematically the structure of the exposure apparatus provided with the aberration measuring device concerning embodiment of this invention. It is a figure which shows schematically the internal structure of the aberration measuring device concerning this embodiment. It is a figure which shows schematically the lens structure of the objective optical system concerning the 1st Example of this embodiment. It is a figure which shows the lateral aberration in 1st Example. It is a figure which shows schematically the lens structure of the objective optical system concerning the 2nd Example of this embodiment. It is a figure which shows the lateral aberration in 2nd Example. It is a flowchart of the method at the time of obtaining the semiconductor device as a microdevice. It is a flowchart of the method at the time of obtaining the liquid crystal display element as a microdevice.

Explanation of symbols

100 light source IL illumination optical system R reticle RS reticle stage PL projection optical system W wafer WS wafer stage TM test mask G1 first lens group G2 second lens group G3 third lens group G4 fourth lens group 10 aberration measuring apparatus 11 objective optical System 11a Pinhole member (first optical member)
12 Micro fly's eye lens 13 CCD
14 Signal processing unit

Claims (8)

In the objective optical system including the first optical member that is disposed closest to the object side and has a predetermined pattern formed on the object side surface,
The image-side surface of the first optical member is formed in a predetermined curved surface shape. 2. The objective optical system according to claim 1, wherein the image-side surface of the first optical member is formed in a curved shape with a convex surface facing the image side. The objective optical system according to claim 2, wherein the image-side surface of the first optical member is a refractive surface. In order from the object side, a first lens group having the first optical member having positive refractive power, a second lens group having at least two positive lenses, a third lens group having at least one positive lens, and at least one The objective optical system according to any one of claims 1 to 3, further comprising a fourth lens group having two negative lenses. When the maximum emission angle of the light beam from the image side surface of the first optical member is a and the numerical aperture of the objective optical system is NA,
a / arcsin (NA) <0.95
The objective optical system according to claim 1, wherein the following condition is satisfied. 6. The objective optical system according to claim 1, wherein at least two optical members in the objective optical system are formed of fluorite. In an aberration measuring apparatus for measuring the wavefront aberration of an imaging optical system,
The objective optical system according to any one of claims 1 to 6, wherein a surface on the object side of the first optical member is positioned on an image plane of the imaging optical system.
The aberration measuring apparatus, wherein the predetermined pattern formed on the object-side surface of the first optical member is a pinhole. In an exposure apparatus that exposes a pattern on a mask onto a photosensitive substrate via a projection optical system,
An exposure apparatus comprising the aberration measuring apparatus according to claim 7 for measuring wavefront aberration of the projection optical system.

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