JP2008304614A - Polarization element and exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarization element for ultraviolet region which is insensitive to a manufacturing error and has a wide usable incident angle range. <P>SOLUTION: The polarization element is constituted such that a first laminated film group 2 which is constituted by alternately laminating a first film and a second film having a refractive index smaller than that of the first film and satisfies relations of 1.2×λ/4<H<1.4×λ/4 and 1.2×λ/4<L<1.4×λ/4 and a second laminated film group 3 which is constituted by alternately laminating the first film and the second film and satisfies relations of 0.9×λ/4<H<1.1×λ/4 and 0.9×λ/4<L<1.1×λ/4 are stacked on a substrate 1. Therein, λ is center wavelength of ultraviolet light made incident to the polarization element, H is optical film thickness of the first film and L is optical film thickness of the second film. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a polarizing element suitable for use in the ultraviolet wavelength region, and further relates to an exposure apparatus using the polarizing element.

With the progress of excimer laser such as ArF laser (wavelength 193 nm) and F ₂ laser (157 nm), development of a semiconductor exposure apparatus using vacuum ultraviolet light is expected.

  An illumination system of a semiconductor exposure apparatus is generally required to have a high NA, and in order to achieve a high NA, a polarizing element capable of efficiently controlling polarization, such as a polarization beam splitter, is necessary. Accordingly, there is a need for a polarizing element that performs highly efficient polarization control on ultraviolet light even in a semiconductor exposure apparatus that uses vacuum ultraviolet light.

  In general, a polarizing element is produced by forming a dielectric film on the inclined surface of a right-angle prism and bonding another right-angle prism to the film surface. However, since there is no adhesive that can be used in a short wavelength region of 200 nm or less, a polarizing element for ultraviolet light is formed by laminating a dielectric film on a flat plate.

  However, it is difficult to produce a multilayer film in the vacuum ultraviolet region because the refractive index and film thickness often change slightly. In general, since the polarizing element is sensitive to the incident angle, the usable incident angle is limited.

  For this reason, there is a demand for a polarizing element having a multilayer film structure as simple as possible and having a wide incident angle.

Patent Document 1 is configured so that the optical film thicknesses of the high-refractive index film and the low-refractive index film satisfy predetermined conditions when the center wavelength of incident light (light branched by the polarization beam splitter) is λ. A polarizing beam splitter provided with the first and second laminated film groups is disclosed.
Japanese Patent Laid-Open No. 08-146218

  However, if a polarizing beam splitter in a lower wavelength region that is sensitive to manufacturing errors is created by the film configuration disclosed in Patent Document 1, it is highly possible that desired characteristics cannot be obtained due to the influence of manufacturing errors. Therefore, there is a need for a film configuration that is less sensitive to manufacturing errors.

  The present invention provides a polarizing element for the ultraviolet region which is insensitive to manufacturing errors and has a wide usable incident angle range.

  The polarizing element according to one aspect of the present invention is configured by alternately stacking a first film and a second film having a refractive index lower than that of the first film, and 1.2 × λ / 4 <H < 1st laminated film group that satisfies 1.4 × λ / 4 and 1.2 × λ / 4 <L <1.4 × λ / 4, and first and second films are alternately laminated. A second laminated film group satisfying 0.9 × λ / 4 <H <1.1 × λ / 4 and 0.9 × λ / 4 <L <1.1 × λ / 4 on the substrate. It is characterized by being laminated. However, (lambda) is the center wavelength of the ultraviolet light which injects into this polarizing element, H is the optical film thickness of a 1st film | membrane, L is the optical film thickness of a 2nd film | membrane.

  An exposure apparatus having a light source that emits ultraviolet light, the polarizing element on which the ultraviolet light is incident, and an optical system that exposes an object to be processed using ultraviolet light having a specific polarization direction from the polarizing element. It constitutes another aspect of the present invention.

  Furthermore, a device manufacturing method including a step of exposing a target object using the exposure apparatus and a step of developing the exposed target object also constitutes another aspect of the present invention.

  According to the polarizing element of the present invention, it is possible to realize a polarizing element for the ultraviolet region having a simple multilayer film configuration, insensitive to manufacturing errors, and having a wide usable incident angle range. Therefore, if the polarizing element is used, a high NA exposure apparatus using ultraviolet light can be realized.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  First, items common to the polarizing beam splitter (polarizing element) according to the embodiment of the present invention will be described.

A. The polarizing beam splitter of the example includes a first film having a high refractive index (hereinafter also referred to as a high refractive index material) and a second film having a low refractive index lower than that of the first film (hereinafter referred to as a low refractive index material). It is a polarizing element configured by alternately laminating a refractive index material) on a substrate. The polarizing element is a laminated film group of first and second films,
1.2 × λ / 4 <H <1.4 × λ / 4 and 1.2 × λ / 4 <L <1.4 × λ / 4
... (1)
A first laminated film group satisfying the above and a laminated film group of the first and second films,
0.9 × λ / 4 <H <1.1 × λ / 4 and 0.9 × λ / 4 <L <1.1 × λ / 4
... (2)
And a second laminated film group satisfying the above. Here, λ is the center wavelength of ultraviolet light incident on the polarizing beam splitter (separated by the polarizing beam splitter), H is the optical film thickness of the first film, and L is the optical film thickness of the second film. It is. From the above (1) and (2), the optical thicknesses (constituent film thicknesses) of the first and second films constituting the first laminated film group are the same as the first and second films constituting the second laminated film group. It is thicker than the optical film thickness (constituent film thickness) of the second film.

  By adopting such a film configuration, it is possible to create a polarizing beam splitter that is insensitive to manufacturing errors and that can be used with a wide incident angle (for example, ± 3 degrees).

  B. Here, preferably, the first laminated film and the second laminated film group are laminated in order from the substrate side. The reason for this will be described later.

  C. Further, the number of repetitions of the first and second films in the first laminated film group is preferably 7 to 10 times. On the other hand, the number of repetitions of the first and second films in the second laminated film group is preferably about 5 to 10 times. In particular, when the polarizing beam splitter of this embodiment is used as a transmissive polarizing beam splitter, if the number of alternating repetitions (number of layers) is large, absorption of incident light becomes large. Furthermore, from the simulation results described later, the number of alternating repetitions of the first and second films in the second stacked film group is equal to or less than the number of alternating repetitions of the first and second films in the first stacked film group. It is better if there is.

  In each laminated film group, the first and second films have the same optical film thickness. However, as indicated by the above conditions (1) and (2), the first and second films in the first stacked film group and the first and second films in the second stacked film group are optically The film thicknesses are different from each other.

  D. Further, an adjustment layer composed of 1 to 5 layers may be provided separately from the first and second laminated film groups. Thereby, the optical characteristics of the polarization beam splitter can be adjusted. The adjustment layer may be provided as a final layer on the laminated film group far from the substrate in the first and second laminated film groups, or may be provided immediately above the substrate. Moreover, you may arrange | position between a 1st laminated film group and a 2nd laminated film group.

  E. The material of the first film preferably contains one or more components of lanthanum fluoride, gadolinium fluoride, neodymium fluoride, dysprosium fluoride, yttrium fluoride, and mixtures or compounds thereof.

  Further, the material of the second film includes one or more components of aluminum fluoride, magnesium fluoride, strontium fluoride, calcium fluoride, sodium fluoride, cryolite, thiolite, and a mixture or compound thereof. It is preferable.

  The condition to be satisfied in the embodiment of the present invention is A, and other matters B to E may not necessarily be satisfied.

  A schematic configuration of the polarizing beam splitter of the embodiment is shown in FIG. Reference numeral 1 denotes a substrate, 2 denotes a first laminated film group, and 3 denotes a second laminated film group. 4 is an adjustment layer.

  Hereinafter, more specific examples (simulation examples) will be described.

In Example 1, CaF ₂ having a refractive index of 1.5 was used as the substrate 1, LaF ₃ having a refractive index of 1.68 was used as the high refractive index material, and AlF ₃ having a refractive index of 1.39 was used as the low refractive index material.

In the first laminated film group 2 arranged on the substrate side, the optical film thickness H of LaF ₃ was set to 1.30 × λ / 4. The optical film thickness L of AlF ₃ was 1.35 × λ / 4. And the alternate lamination of these LaF ₃ and AlF ₃ was repeated 10 times.

On the other hand, in the second laminated film group 3, the optical film thickness H of LaF ₃ was set to 1.04 × λ / 4. The optical film thickness L of AlF ₃ was set to 1.08 × λ / 4. And these alternate lamination of LaF ₃ and AlF ₃ was repeated 7 times.

As the final adjustment layer 4, LaF ₃ (H = 1.30 × λ / 4), AlF ₃ (L = 1.14 × λ / 4), and LaF ₃ (H = 1.54 × λ / 4).

  λ is 193 nm.

  FIG. 2 schematically shows the film configuration of the polarizing beam splitter of this example. Further, the left column of FIG. 2 shows the film material, and the right column shows the optical film thickness. The medium on the second laminated film group side (adjustment layer side) here is air (atmosphere).

  Moreover, the simulation result of the relationship between the transmittance | permeability and the wavelength of the polarizing beam splitter of a present Example is shown in FIG. Furthermore, the simulation result of the relationship between the transmittance and the incident angle is shown in FIG. 3 and 4, Ts indicates the transmittance for S-polarized light, and Tp indicates the transmittance for P-polarized light.

  From these figures, in the wavelength region of 193 nm, good characteristics with Tp of 90% or more and Ts of 10% or less are obtained at an angle of ± 3 degrees centering on an incident angle of 58 degrees equal to the Brewster angle. I understand.

  Furthermore, the simulation result of the relationship between a reflectance and an incident angle is shown in FIG. Rs represents the reflectance for S-polarized light, and Rp represents the reflectance for P-polarized light.

  FIG. 5 shows that polarization separation can be performed with high efficiency even when used as a reflective polarization beam splitter.

  Here, as described above, the constituent film thickness of the first laminated film group is made thicker than the constituent film thickness of the second laminated film group, and the second laminated film group having a thicker constituent film thickness is used. The reason why it is better to dispose on the substrate side than the laminated film group will be described.

FIG. 6 shows a polarizing beam splitter in which the constituent film thickness of the first laminated film group 2 ′ is made thinner than the constituent film thickness of the second laminated film group 3 ′. That is, the first laminated film group 2 ′ is composed of LaF ₃ (H = 1.04 × λ / 4) and AlF ₃ (L = 1.08 × λ / 4), and the second laminated film group In this example, 3 ′ is composed of LaF ₃ (H = 1.30 × λ / 4) and AlF ₃ (L = 1.35 × λ / 4). The adjustment layer 4 is the same as the polarizing beam splitter of this embodiment shown in FIG.

  In FIG. 7, the simulation result of the transmittance | permeability in the incident angle 57 degrees in the polarizing beam splitter of a present Example is shown. The X axis indicates the film thickness, and the Y axis indicates the transmittance. The wavelength is 193 nm. On the other hand, FIG. 8 shows a simulation result with the transmittance at an incident angle of 57 ° in the polarizing beam splitter having the film configuration shown in FIG. The X axis indicates the film thickness, and the Y axis indicates the transmittance. The X axis represents the film thickness, and the Y axis represents the transmittance.

  Comparing FIG. 7 and FIG. 8, basically the same characteristics are obtained, but FIG. 8 shows a change in the Ts characteristic with respect to the film thickness in the film thickness region closer to the atmosphere side as compared to FIG. large. This means that the polarizing beam splitter of this embodiment shown in FIG. 7 is more sensitive to manufacturing errors. That is, the polarizing beam splitter of the present embodiment has a stronger film configuration against manufacturing errors.

Even when 157 nm (F ₂ laser) is used as the incident light, if a film configuration similar to that of Example 1 is employed, a polarizing beam splitter that can be used at an incident angle of Brewster angle ± 3 degrees can be realized. In FIG. 9, the film | membrane structure is shown as Example 2 of this invention.

In FIG. 9, a substrate (CaF ₂ ) having a refractive index of 1.55 is used, GdF ₃ having a refractive index of 1.75 is used as a high refractive index material, and AlF ₃ having a refractive index of 1.41 is used as a low refractive index material. .

In the first laminated film group 2 on the substrate side, alternating lamination of GdF ₃ (H = 1.30 × λ / 4) and AlF ₃ (L = 1.33 × λ / 4) was repeated 10 times. In the second laminated film group 3, alternating lamination of GdF ₃ (H = 0.96 × λ / 4) and AlF ₃ (L = 0.98 × λ / 4) was repeated 10 times.

Further, as the final adjustment layer 4, GdF ₃ (H = 1.30 × λ / 4), AlF ₃ (L = 1.20 × λ / 4), and GdF _{3 are} sequentially formed from the second stacked film group side. Three layers (H = 1.27 × λ / 4) were provided.

  In FIG. 10, the simulation result of the relationship between the transmittance | permeability in the polarizing beam splitter of a present Example and an incident angle is shown. From FIG. 10, in the wavelength region of 157 nm, good characteristics with Tp of 90% or more and Ts of 10% or less are obtained at an angle of ± 3 degrees centering on an incident angle of 58 degrees equal to the Brewster angle. I understand.

  As described above, according to each of the above-described embodiments, it is possible to realize a polarizing beam splitter having high characteristics that can be used at an incident angle of Brewster angle ± 3 degrees insensitive to manufacturing errors in a vacuum ultraviolet region of 200 nm or less.

  As Embodiment 3 of the present invention, an exposure apparatus using the polarization beam splitter described in Embodiments 1 and 2 will be described with reference to FIG.

  The exposure apparatus is a projection exposure apparatus that exposes a processing object 400 to a circuit pattern formed on a reticle 200 by, for example, a step-and-repeat method or a step-and-scan method. The exposure apparatus is suitable for a lithography process of sub-micron or quarter-micron or less, and in this embodiment, a step-and-scan type exposure apparatus (also referred to as “scanner”) will be described as an example.

  Here, the “step and scan method” means that the wafer is continuously scanned (scanned) with respect to the reticle to expose the reticle pattern onto the wafer, and the wafer is stepped after completion of one shot of exposure. The exposure method moves to the next exposure area. The “step-and-repeat method” is an exposure method in which the wafer is moved stepwise to the exposure area of the next shot for every batch exposure of the wafer.

  The exposure apparatus includes an illumination apparatus 100, a reticle stage (not shown) on which the reticle 200 is mounted, a projection optical system 300, a wafer stage 500 on which the object 400 is mounted, and a control unit 600.

  The illumination device 100 illuminates a reticle 200 on which a transfer circuit pattern is formed, and includes a light source unit 110 and an illumination optical system 120.

For the light source unit 110, for example, an ArF excimer laser having a wavelength of about 193 nm or an F ₂ laser having a wavelength of about 157 nm is used.

  The illumination optical system 120 is an optical system that illuminates the surface to be illuminated (reticle 200) using ultraviolet light emitted from the light source unit 110. The illumination optical system 120 of this embodiment includes a random phase plate 121, the polarizing beam splitter 121 described in the first or second embodiment, the microlens array 123, the inner surface reflecting member 124, the optical elements 125a and 125b, and a condenser. And a lens 126. Further, the illumination optical system 120 includes a variable magnification relay optical system 127, a polarization separation film 128, a fly-eye lens 129, a condenser lens 130, a half mirror 131, a sensor 132, and a relay optical system 133. .

  The polarization beam splitter 121 separates a specific polarized light component from the laser emitted from the light source unit. Higher NA can be achieved by further rotating and adjusting the polarization by the phase plate 122.

  A microlens array (hereinafter referred to as MLA) 123 includes a plurality of elements having a lens action formed integrally with a substrate in an array, and forms a number of two-dimensional light sources using light beams emitted from the light source unit 110. The inner surface reflecting member 124 reflects the light emitted from the MLA 123 so that the light is uniformly distributed on the emitting surface of the inner surface reflecting member 124.

  The optical elements 125a and 125b are diffractive optical elements such as a computer generated hologram (hereinafter referred to as CGH) or refractive optical elements such as a microlens array (MLA). The optical elements 125a and 125b are arranged so that a plurality of CGHs and / or a plurality of MLAs can be switched. As the MLA, a field type hexagonal microlens array (hexagonal MLA) or a circular microlens array (circle MLA) is used. The CGH can form an effective light source having an arbitrary shape, and can form an annular shape, a quadrupole shape, a dipole shape, or the like. That is, the optical elements 125a and 125b have a function of defining the shape of the effective light source on the pupil plane.

  The condenser lens 126 forms a Fourier image of CGH or MLA at position A. Condenser lens 126 has a hexagonal illuminance distribution at position A when optical elements 125a and 125b are hexagonal MLA, and a uniform circular illuminance distribution at position A when optical elements 125a and 125b are circular MLA. Form.

  The variable power relay optical system 127 projects the illuminance distribution formed at the position A onto the incident surface of the fly-eye lens 129.

  The polarization separation film 128 is disposed so as to be inserted into and removed from the optical path at an angle. The polarization separation film 128 is formed on a parallel plane plate, and generally transmits P-polarized light and reflects S-polarized light with respect to the parallel plane plate.

  The fly-eye lens 129 forms a plurality of secondary light sources at the pupil position of the illumination optical system 120. The condenser lens 130 forms a uniform light distribution by superimposing the light from the secondary light source formed by the fly-eye lens 129 on the position B. At position B, a variable diaphragm (not shown) that controls the illumination area of the surface to be illuminated is disposed. Further, the condenser lens 130 has a function of reflecting a part of the light reflected by the half mirror 131 and making it incident on the sensor 132 as will be described later.

  The half mirror 131 branches (reflects) part of light (exposure light) emitted from the light source unit 110.

  The sensor 132 is an exposure amount sensor that monitors the exposure amount on the workpiece 400. Thereby, it is possible to monitor the exposure amount while exposing the object 400 to be processed. An illuminance meter 510 that measures the illuminance on the surface of the workpiece 400 is provided on the wafer stage 500 described later. The relationship between the exposure amount detected by the sensor 132 and the illuminance on the surface of the object to be processed 400 changes depending on the change in transmittance of the projection optical system 300 or the like. For this reason, the illuminometer 510 is periodically arranged in the optical path, and the illuminance detected by the illuminometer 510 and the exposure amount detected by the sensor 132 are related and stored in the control unit 600 described later.

  The relay optical system 133 projects the light distribution at position B onto the pattern surface drawn on the reticle 200.

  According to the illumination optical system 120 configured in this way, it is possible to reduce the difference in transmittance depending on the polarization state of light with respect to the half mirror 131 inserted in the exposure optical path, and desired polarization illumination. It can be performed. Accordingly, it is possible to perform transfer with good resolution in an exposure apparatus having a projection optical system with a high NA.

  The reticle 200 is made of, for example, quartz, on which a circuit pattern (or image) to be transferred is formed, and is supported and driven by a reticle stage (not shown). Diffracted light emitted from the reticle 200 passes through the projection optical system 300 and is projected onto the object 400 to be processed. The reticle 200 and the workpiece 400 are arranged in an optically conjugate relationship. Since the exposure apparatus 1 of this embodiment is a scanner, the pattern of the reticle 200 is transferred onto the target object 400 by scanning the reticle 200 and the target object 400 at the speed ratio of the reduction magnification ratio. Note that in the case of a step-and-repeat type exposure apparatus (also referred to as a stepper), exposure is performed with the reticle 200 and the workpiece 400 stationary.

  The projection optical system 300 is an optical system that projects light reflecting the pattern on the reticle 200 onto the object 400 and has a numerical aperture (NA) of 0.9 or more. The projection optical system 300 reduces and projects the circuit pattern formed on the reticle 200 onto the object to be processed 400 by a factor of 1/4.

  The projection optical system 300 includes an optical system composed of only a plurality of lens elements, an optical system having a plurality of lens elements and at least one concave mirror (catadioptric optical system), and diffractive optics such as a plurality of lens elements and kinoform. An optical system having an element can be used. An all-mirror optical system can also be used.

  When correction of chromatic aberration is required, a plurality of lens elements made of glass materials having different dispersion values (Abbe values) can be used, or the diffractive optical element can be configured to generate dispersion in the opposite direction to the lens element. To do. In addition, the projection optical system 300 includes an immersion type projection optical system in which a space between the final lens closest to the object to be processed 400 and the object to be processed 400 is immersed in water or other high refractive index liquid, a solid immersion type projection optical system, or the like. May be an optical system having a numerical aperture (NA) of 1.0 or more.

  The object to be processed 400 is a wafer in this embodiment, but widely includes liquid crystal substrates and other objects to be processed. A photoresist is applied to the object to be processed 400.

  Wafer stage 500 supports object 400 to be processed. The wafer stage 500 can move the workpiece 400 in the xyz direction using, for example, a linear motor. The reticle 200 and the workpiece 400 are scanned synchronously, the positions of the wafer stage 500 and the reticle stage (not shown) are monitored by a laser interferometer or the like, and both are driven at a constant speed ratio.

  Wafer stage 500 is provided on a stage surface plate supported on a floor or the like via a damper, and reticle stage and projection optical system 300 are supported on a base frame mounted on the floor or the like via a damper. It is provided on a lens barrel surface plate (not shown).

  The control unit 600 includes a CPU, MPU, or memory (not shown) and controls the operation of the exposure apparatus. The controller 600 is electrically connected to the illumination device 100, a reticle stage (not shown), and the wafer stage 500. The memory is composed of a ROM and a RAM, and stores firmware for operating the exposure apparatus. The control unit 600 calculates the exposure amount to the workpiece 400 from the relationship between the exposure amount and the illuminance input from the sensor 132 and the illuminance meter 510, and controls the exposure amount based on the calculated exposure amount.

  In the exposure, the luminous flux emitted from the light source unit 110 illuminates the reticle 200 by the illumination optical system 120, for example, Koehler illumination. Light that passes through the reticle 200 and reflects the reticle pattern is imaged on the object 400 by the projection optical system 300. At this time, the illumination optical system 120 can reduce the difference in transmittance due to the polarization state of the half mirror 131, so that the light having the optimum effective light source shape and polarization state is formed for the reticle pattern. Can do. Thus, a desired resolution can be achieved and high-quality exposure can be performed on the workpiece 400.

  In addition, since it is possible to supply light having a desired polarization state even to a high NA projection optical system, a device (for example, a semiconductor element, an LCD element, a CCD sensor, a CMOS sensor, etc.) with high throughput and high efficiency. Imaging device, thin film magnetic head).

  Next, an embodiment of a device manufacturing method using the above-described exposure apparatus will be described with reference to FIGS.

  FIG. 12 is a flowchart for explaining how to fabricate devices (ie, semiconductor chips such as IC and LSI, LCDs, CCDs, and the like). Here, the manufacture of a semiconductor chip will be described as an example.

  In step 1 (circuit design), a device circuit is designed. In step 2 (mask production), a mask on which the designed circuit pattern is formed is produced. In step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the mask and the wafer.

  Step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer created in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). Including. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device created in step 5 are performed. Through these steps, the semiconductor device is completed and shipped (step 7).

  FIG. 13 is a detailed flowchart of the wafer process in Step 4. In step 11 (oxidation), the surface of the wafer is oxidized. In step 12 (CVD), an insulating film is formed on the surface of the wafer. In step 13 (electrode formation), an electrode is formed on the wafer by vapor deposition or the like. Step 14 (ion implantation) implants ions into the wafer. In step 15 (resist process), a photosensitive agent is applied to the wafer.

  Step 16 (exposure) uses the exposure apparatus 1 to expose a circuit pattern on the mask onto the wafer. In step 17 (development), the exposed wafer is developed.

  In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), the resist that has become unnecessary after the etching is removed. By repeatedly performing these steps, multiple circuit patterns are formed on the wafer.

  According to the device manufacturing method of the present embodiment, it is possible to manufacture a device of higher quality than before.

  The embodiments described above are merely representative examples, and various modifications and changes can be made to the embodiments when the present invention is implemented.

The schematic diagram which shows the structure of the polarizing beam splitter which is an Example of this invention. 1 is a diagram illustrating a film configuration of a polarizing beam splitter (for 193 nm) of Example 1. FIG. FIG. 3 is a diagram illustrating a relationship between a wavelength and a transmittance of the polarizing beam splitter according to the first embodiment. The figure which shows the relationship between the incident angle and transmittance | permeability of the polarizing beam splitter of Example 1. FIG. FIG. 3 is a diagram illustrating a relationship between an incident angle and a reflectance of the polarizing beam splitter according to the first embodiment. FIG. 3 is a diagram illustrating a film configuration of a polarizing beam splitter in which the film configuration is reversed from that of the first embodiment. FIG. 6 is a diagram showing the transmittance at an incident angle of 57 ° in the polarizing beam splitter of the first embodiment. The figure which shows the transmittance | permeability in 57 degrees of incident angles in the polarizing beam splitter of FIG. The figure which shows the film | membrane structure of the polarizing beam splitter (for 157 nm) which is Example 2 of this invention. FIG. 6 is a diagram illustrating a relationship between an incident angle and a transmittance of the polarizing beam splitter according to the second embodiment. FIG. 10 is a view showing the arrangement of an exposure apparatus that is Embodiment 3 of the present invention. 9 is a flowchart showing a device manufacturing method using the exposure apparatus of Example 3. 9 is a flowchart showing a device manufacturing method using the exposure apparatus of Example 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 1st laminated film group 3 2nd laminated film group 4 Adjustment layer 122 Polarization beam splitter

Claims (6)

The first film and the second film having a lower refractive index than the first film are alternately stacked,
1.2 × λ / 4 <H <1.4 × λ / 4 and 1.2 × λ / 4 <L <1.4 × λ / 4
A first laminated film group satisfying
The first and second films are alternately stacked, and
0.9 × λ / 4 <H <1.1 × λ / 4 and 0.9 × λ / 4 <L <1.1 × λ / 4
A polarizing element, wherein a second laminated film group satisfying the requirements is laminated on a substrate.
Where λ is the center wavelength of the ultraviolet light incident on the polarizing element, H is the optical film thickness of the first film, and L is the optical film thickness of the second film.   The polarizing element according to claim 1, wherein the first laminated film group and the second laminated film group are laminated in order from the substrate side.   The number of alternating repetitions of the first and second films in the second stacked film group is less than or equal to the number of alternating repetitions of the first and second films in the first stacked film group. The polarizing element according to claim 1. The material of the first film includes one or more components of lanthanum fluoride, gadolinium fluoride, neodymium fluoride, dysprosium fluoride, yttrium fluoride, and mixtures or compounds thereof,
The material of the second film includes one or more components of aluminum fluoride, magnesium fluoride, strontium fluoride, calcium fluoride, sodium fluoride, cryolite, thiolite, and mixtures or compounds thereof. The polarizing beam splitter according to claim 1, wherein the polarizing beam splitter is characterized in that: A light source that emits ultraviolet light;
The polarizing element according to any one of claims 1 to 4, wherein the ultraviolet light is incident;
An exposure apparatus comprising: an optical system that exposes an object to be processed using ultraviolet light from the polarizing element. Exposing the object to be processed using the exposure apparatus according to claim 5;
And developing the exposed object to be processed.