Source: http://www.google.com/patents/US20090002675?dq=6948823
Timestamp: 2017-06-27 16:14:17
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Patent US20090002675 - Polarization-modulating optical element - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inPatentsA polarization-modulating optical element consisting of an optically active crystal material has a thickness profile where the thickness, as measured in the direction of the optical axis, varies over the area of the optical element. The polarization-modulating optical element has the effect that the...http://www.google.com/patents/US20090002675?utm_source=gb-gplus-sharePatent US20090002675 - Polarization-modulating optical elementAdvanced Patent SearchTry the new Google Patents, with machine-classified Google Scholar results, and Japanese and South Korean patents.Publication numberUS20090002675 A1Publication typeApplicationApplication numberUS 12/205,572Publication dateJan 1, 2009Filing dateSep 5, 2008Priority dateJan 16, 2004Also published asCN1910522A, CN1910522B, CN101726863A, CN101726863B, CN101793993A, CN101793993B, CN101799587A, CN101799587B, CN101799637A, CN101799637B, EP1716457A2, EP1716457B1, EP1716457B9, US8279524, US8289623, US8320043, US8711479, US8861084, US9316772, US20070081114, US20080316598, US20100177293, US20130222778, US20140102355, WO2005069081A2, WO2005069081A3Publication number12205572, 205572, US 2009/0002675 A1, US 2009/002675 A1, US 20090002675 A1, US 20090002675A1, US 2009002675 A1, US 2009002675A1, US-A1-20090002675, US-A1-2009002675, US2009/0002675A1, US2009/002675A1, US20090002675 A1, US20090002675A1, US2009002675 A1, US2009002675A1InventorsDamian Fiolka, Markus DeguentherOriginal AssigneeCarl Zeiss Smt AgExport CitationBiBTeX, EndNote, RefManPatent Citations (98), Referenced by (54), Classifications (27), Legal Events (4) External Links: USPTO, USPTO Assignment, EspacenetPolarization-modulating optical element
US 20090002675 A1Abstract
114. The production method of the polarization-modulating element according to claim 108, wherein the step of preparing the optical material with optical activity is to set the optical material so that a crystallographic axis thereof coincides with a traveling direction of the incident light. Description
[0009] The present invention therefore has the objective to propose a polarization-modulating optical element which—with a minimum loss of intensity—affects the polarization of light rays in such a way that from linearly polarized light with a first distribution of the directions of the oscillation planes of individual light rays, the optical element generates linearly polarized light with a second distribution of the directions of the oscillation planes of individual light rays.
[0014] In order to generate from linearly polarized light an arbitrarily selected distribution of linearly polarized light rays with a minimum loss of intensity, an optically active crystal with an optical axis is used as raw material for the polarization-modulating optical element. The optical axis of a crystal, also referred to as axis of isotropy, is defined by the property that there is only one velocity of light propagation associated with the direction of the optical axis. In other words, a light ray traveling in the direction of an optical axis is not subject to a linear birefringence. The polarization-modulating optical element has a thickness profile that varies in the directions perpendicular to the optical axis of the crystal. The term “linear polarization distribution” in this context and hereinafter is used with the meaning of a polarization distribution in which the individual light rays are linearly polarized but the oscillation planes of the individual electrical field vectors can be oriented in different directions.
[0023] In a further advantageous embodiment of the invention, a plane of oscillation of linearly polarized light passing through the polarization-modulating optical element is rotated by a first angle of rotation β1 within at least one of said first plan-parallel portions and by a second angle of rotation β2 within at least one of said second plan-parallel portions, such that β1 and β2 are approximately conforming or conform to the expression |β2−β1|=(2n+1)·90°, with n representing an integer.
[0024] In an advantageous embodiment, β1 and β2 are approximately conforming or conform to the expressions β1=90°+p·180°, with p representing an integer, and β2=q·180°, with q representing an integer other than zero. As will discussed below in more detail, such an embodiment of the polarization modulating optical element may be advantageously used in affecting the polarization of traversing polarized light such that exiting light has a polarization distribution being—depending of the incoming light—either approximately tangentially or approximately radially polarized.
[0028] In a further advantageous embodiment of the invention, the polarization-modulating optical element comprises a first group of substantially planar-parallel portions wherein a plane of oscillation of traversing linearly polarized light is rotated by a first angle of rotation β1, and a second group of substantially planar-parallel portions wherein a plane of oscillation of traversing linearly polarized light is rotated by a second angle of rotation, such that β1 and β2 are approximately conforming or conform to the expression |β2−β1|=(2n+1)·90°, with n representing an integer.
[0029] In a further advantageous embodiment of the invention, β1 and β2 are approximately conforming to the expressions β1=90°+p·180°, with p representing an integer, and β2=q·180°, with q representing an integer other than zero.
[0036] The further polarization-modulating optical element that can be placed in the optical arrangement can in particular be designed in such a way that it rotates the oscillation plane of a linearly polarized light ray by 90°. This is particularly advantageous if the first polarization-modulating element in the optical arrangement produces a tangential polarization. By inserting the 90′-rotator, the tangential polarization can be converted to a radial polarization.
[0044] FIG. 4 a schematically illustrates a second exemplary embodiment of a polarization-modulating optical element;
[0045] FIG. 4 b illustrates the thickness profile as a function of the azimuth angle in the embodiment of the polarization-modulating optical element of FIG. 4 a; [0046] FIG. 4 c illustrates the thickness profile as a function of the azimuth angle in a further embodiment of the polarization-modulating optical element;
[0047] FIG. 4 d illustrates the thickness profile as a function of the azimuth angle in the embodiment of the polarization-modulating optical element of FIG. 3;
[0048] FIG. 4 e illustrates the thickness profile as a function of the azimuth angle in a further embodiment of the polarization-modulating optical element;
[0049] FIG. 4 f schematically illustrates a further exemplary embodiment of a polarization-modulating optical element;
[0050] FIG. 5 schematically illustrates the polarization distribution of a bundle of light rays before and after passing through the polarization-modulating optical element with the thickness profile according to FIG. 3 or 4 d; [0051] FIG. 6 schematically illustrates the polarization distribution of a bundle of light rays before and after passing through an optical arrangement with the polarization-modulating optical element with the thickness profile according to FIG. 3 and a further polarization-modulating optical element;
[0052] FIG. 7 a schematically illustrates the polarization distribution of a bundle of light rays before and after passing through an optical arrangement with the polarization-modulating optical element with the thickness profile according to FIG. 4 e and a planar-parallel plate, one half of which is configured as a half-wave plate;
[0053] FIG. 7 b shows a plan view of a planar-parallel plate, one half of which is configured as a half-wave plate;
[0061] It is also important for the present invention, applying optically active materials in an illumination system and/or an objective of a projection optical system of e.g. a projection apparatus used in microlithography, that also the temperature dependency of the specific rotation is considered. The temperature dependency of the specific rotation α for a given wavelength is to a good and first linear approximation given by α(T)=α0(T0)+γ*(T−T0), where γ is the linear temperature coefficient of the specific rotation α. In this case α(T) is the optical activity coefficient or specific rotation at the temperature T and α0 is the specific rotation at a reference temperature T0. For optical active quartz material the value γ at a wavelength of 193 nm and at room temperature is γ=2.36 mrad/(mm*K).
[0064] More general, alternative or in addition to the variation of the thickness d=d(x,y) of the polarization-modulating element, the specific rotation α may itself be dependent on the location within the modulating element such that α becomes an α(x, y, z) or α(r, θ, z), where x,y or r,θ are Cartesian or polar coordinates in a plane perpendicular to the element axis EA (or alternative to the optical axis OA) of the polarization-modulating element, as shown e.g. in FIG. 1, where z is the axis along the element axis EA. Of course also a description in spherical-coordinates like r, θ, φ, or others is possible. Taking into account the variation of the specific rotation α, the polarization-modulating optical element in general comprises a varying profile of the “optical effective thickness D” defined as D(x,y)=d(x,y)*α(x,y), if there is no dependency of α in z-direction. In the case that α may also depend on the z-direction (along the optical axis or element axis EA, or more general along a preferred direction in an optical system or a direction parallel to the optical axis of an optical system) D has to be calculated by integration D(x,y)=∫α(x, y, z) dz(x,y), along the polarization-modulating optical element. In general, if a polarization-modulating optical element is used in an optical system, having an optical axis or a preferred direction defined by the propagation of a light beam through the optical system, the optical effective thickness D is calculated by integrating the specific rotation α along the light path of a light ray within the polarization-modulating optical element. Under this general aspect the present invention relates to an optical system comprising an optical axis or a preferred direction given by the direction of a light beam propagating through the optical system. The optical system also comprises a polarization-modulating optical element described by coordinates of a coordinate system, wherein one preferred coordinate of the coordinate system is parallel to the optical axis of the optical system or parallel to the preferred direction. As an example, in the above case this preferred direction was the z-coordinate which is the preferred coordinate. Additionally the polarization-modulating optical element comprises optical active material and also a profile of effective optical thickness D as defined above, wherein the effective optical thickness D varies at least as a function of one coordinate different from the preferred coordinate of the coordinate system describing the polarization-modulating optical element. In the above example the effective optical thickness D varies at least as a function of the x- or y-coordinate, different from the z-coordinate (the preferred coordinate). There are different independent methods to vary the effective optical thickness of an optical active material. One is to vary the specific rotation by a selection of appropriate materials, or by subjecting the optically active material to a non-uniform temperature distribution, or by varying the geometrical thickness of the optically active material. Also combinations of the mentioned independent methods result in a variation of the effective optical thickness of an optical active material.
[0065] FIG. 3 illustrates an embodiment of the polarization-modulating optical element 301 which is suited specifically for producing a tangential polarization. A detailed description will be presented in the context of FIGS. 4 d and 5. The embodiment illustrated in FIG. 3 will serve to introduce several technical terms that will be used hereinafter with the specific meanings defined here.
[0066] The polarization-modulating optical element 301 has a cylindrical shape with a base surface 303 and an opposite surface 305. The base surface 303 is designed as a planar circular surface. The element axis EA extends perpendicular to the planar surface. The opposite surface 305 has a contour shape in relation to the element axis EA in accordance with a given thickness profile. The optical axis of the optically active crystal runs parallel to the element axis EA. The reference axis RA, which extends in the base plane, intersects the element axis at a right angle and serves as the reference from which the azimuth angle θ is measured. In the special configuration illustrated in FIG. 3, the thickness of the polarization-modulating optical element 301 is constant along a radius R that is perpendicular to the element axis EA and directed at an angle θ relative to the reference axis RA. Thus, the thickness profile in the illustrated embodiment of FIG. 3 depends only on the azimuth angle θ and is given by d=d(θ). The optical element 301 has an optional central bore 307 coaxial with the element axis EA. In an other preferred embodiment of the polarization-optical element the thickness may vary along the radius R such that the thickness profile is d=d(R,θ). In a further more generalized preferred embodiment the thickness profile shown in FIG. 3 is not representing the geometrical thickness d of the polarization-optical element, as described above, but the profile represents the optical effective thickness D=D(R,θ)=D(x,y), depending on the used coordinate system. In this case also any profile of the specific rotation like e.g. α=α(x,y)=α(R,θ) or α=α(x, y, z)=α(R, θ, z) is considered in the profile of the polarization-modulating optical element which is effective for a change in the direction of the polarization plane of a passed light beam.
[0068] FIG. 4 a schematically illustrates a further embodiment of the polarization-modulating optical element 401. The element axis EA through the center of the polarization-modulating optical element 401 in this representation runs perpendicular to the plane of the drawing, and the optical crystal axis of the crystal runs parallel to the element axis. Like the embodiment of FIG. 3, the polarization-modulating optical element 401 has an optional central bore 407. The polarization-modulating optical element 401 is divided into a large number of planar-parallel portions 409 in the shape of sectors of a circle which differ in their respective thicknesses. Alternative embodiments with different shapes of the portions 409 are conceivable. They could be configured, e.g., as hexagonal, square, rectangular or trapeze-shaped raster elements.
[0069] As described in connection with FIG. 3, the embodiment according to FIG. 4 a can be modified such that the different thicknesses of the sectors should be understood as different effective optical thicknesses D. In this case the specific rotation α may vary from one segment to the other too. To manufacture such an embodiment, the polarization-modulating optical element can e.g. have a shape as shown in FIG. 4 a in which the sectors 409 are at least partly exchanged e.g. by any optical inactive material, which is the simplest case to vary the specific rotation α to zero. Also as a further embodiment the sectors 409 may be replaced by cuvettes or cells which are filed with an optical active or optical inactive liquid. In this case the polarization-modulating optical element may comprise optical active and optical inactive sections. If the sectors 409 are only party replaced by cuvettes or if at least one cuvette is used in the polarization-modulating optical element 401, a combination of e.g. optical active crystals with e.g. optical active or optical inactive liquids in one element 40 is possible. Such an optical system according to the present invention may comprise a polarization-modulating optical element which comprises an optically active or an optically inactive liquid and/or an optically active crystal. Further, it is advantageously possible that the polarization-modulating optical element of the optical system according to the present invention comprises clockwise and counterclockwise optically active materials. These materials could be solid or liquid optically active materials. Using liquids in cuvettes has the advantage that by changing the liquids, or the concentration of the optical active material within the liquid, the magnitude of the change in polarization can be easily controlled. Also any thermal changes of the specific rotation α due to the thermal coefficient γ of the specific rotation α can be controlled e.g. by temperature control of the optical active liquid such that either the temperature is constant within the cuvette, or that the temperate has predefined value T such that the specific rotation will have the value α(T)=α0(T0)+γ*(T−T0). Also the formation of a certain temperature distribution within the liquid may be possible with appropriate heating and/or cooling means controlled by control means.
[0071] FIG. 4 b shows the thickness profile along an azimuthal section d(r=const.,θ) for the polarization-modulating optical element 401 divided into sectors as shown in FIG. 4 a. The term azimuthal section as used in the present context means a section traversing the thickness profile d(θ,r) along the circle 411 marked in FIG. 4 a, i.e., extending over an azimuth angle range of 0 °≦θ≦360° at a constant radius r. In general the profile shows the optical effective thickness D=D(θ) along a circle 411.
[0072] An azimuthal section of a polarization-modulating optical element 401 that is divided into sector-shaped portions has a stair-shaped profile in which each step corresponds to the difference in thickness d or optical effective thickness D between neighboring sector elements. The profile has e.g. a maximum thickness dmax and a minimum thickness dmin. In order to cover a range of 0≦β≦360° for the range of the angle of rotation of the oscillation plane of linearly polarized light, there has to be a difference of 360°/αbetween dmax and dmin. The height of each individual step of the profile depends on the number n of sector elements and has a magnitude of 360°/(n·α). At the azimuth angle θ=0°, the profile has a discontinuity where the thickness of the polarization-modulating optical element 401 jumps from dmin to dmax. A different embodiment of the optical element can have a thickness profile in which an azimuthal section has two discontinuities of the thickness, for example at θ=0° and θ=180°.
[0073] In an alternative embodiment the profile has e.g. a maximum optical effective thickness Dmax and a minimum optical effective thickness Dmin, and the geometrical thickness d is e.g. constant, resulting in a variation of the specific rotation α of the individual segments 409 of the element 401. In order to cover a range of 0 ≦β≦360° for the range of the angle of rotation of the oscillation plane of linearly polarized light, there has to be a difference of 360°/d between αmax and αmin. The change of the specific rotation of each individual step of the profile depends on the number n of sector elements 409 and has a magnitude of 360°/(n·d). At the azimuth angle θ=0°, the profile has a discontinuity regarding the optical effective thickness where it jumps from Dmin to Dmax. It should be pointed out, that advantageously in this embodiment there is no discontinuity in the geometrical thickness d of the polarization-modulating element 401. Also the thickness profile of the optical effective thickness in which an azimuthal section has two discontinuities of the optical effective thickness can easily be realized, for example at θ=0° and θ=180°. To realize the defined changes in magnitude of the specific rotation of Δα=360°/(n·d) (if there a n angular segments 409 to form the element 401), the individual sector elements 409 are preferably made of or comprises cuvettes or cells, filled with an optical active liquid with the required specific rotation α. As an example, for the m-th sector element the specific rotation is α(m)=αmin+m*360°/(n·d), and 0≦m≦n. The required specific rotation e.g. can be adjusted by the concentration of the optical active material of the liquid, or by changing the liquid material itself.
[0077] An example of a continuously varying thickness profile is illustrated in FIG. 4 c. The azimuthal section 411 in this embodiment shows a linear decrease in thickness (in general optical effective thickness) with a slope m=−180°/(α·π) over an azimuth-angle range of 0≦θ≦360°. Here the slope is defined a slope of a screw. Alternatively the slope can be defined by m=−180°/(α*π*r) where r is the radius of a circle centered at the element axis EA. In this case the slope depends on the distance of the element axis, e.g. if the polarization-modulating optical element 301 has a given constant screw-slope (lead of a screw).
[0078] The symbol α in this context stands for the specific rotation of the optically active crystal. As in the previously described embodiment of FIG. 4 b, the thickness profile of FIG. 4 c has likewise a discontinuity at the azimuth angle θ=0°, the thickness of the polarization-modulating optical element 401 jumps from dmin to dmax by an amount of approximately 360°/α.
[0079] A further embodiment of a polarization-modulating optical element which is shown in FIG. 4 d has a thickness profile (in general optical effective thickness profile) which is likewise suitable for producing a continuous distribution of linear polarizations, in particular a tangentially oriented polarization. This thickness profile corresponds to the embodiment shown in FIG. 3, in which the angle θ is measured in counterclockwise direction. The azimuthal section 411 in this embodiment is a linear function of the azimuth angle θ with a slope m=−180°/(α·π) over each of two ranges of 0<θ<180° and 180°<θ<360°. The thickness profile has discontinuities at θ=0° and θ=180° where the thickness rises abruptly from dmin to dmax by an amount of 180°/α.
[0080] FIG. 4 e represents the thickness profile (in general optical effective thickness profile) along an azimuthal section for a further embodiment of the polarization-modulating optical element 401. The azimuthal section is in this case a linear function of the azimuth angle θ with a first slope m for 0<θ<180° and with a second slope n for 180°<θ<360°. The slopes m and n are of equal absolute magnitude but have opposite signs. The respective amounts for m and n at a distance r from the element axis are m=−180°/(α·π·r) and n=180°/(α·π·r). While the difference between the minimum thickness dmin and the maximum thickness dmax is again approximately 180°/α, i.e., the same as in the embodiment of FIG. 4 d, the concept of using opposite signs for the slope in the two azimuth angle ranges avoids the occurrence of discontinuities.
[0083] It is furthermore necessary for reasons of mechanical stability to design the polarization-modulating optical element with a minimum thickness dmin of no less than two thousandths of the element diameter. It is particularly advantageous to use a minimum thickness of dmin=N·90°/α, where N is a positive integer. This design choice serves to minimize the effect of birefringence for rays of an incident light bundle which traverse the polarization-modulating element at an angle relative to the optical axis.
[0084] FIG. 4 f schematically illustrates a further embodiment 421 of the polarization-modulating optical element. As in FIG. 4 a, the element axis EA through the center of the polarization-modulating optical element 421 runs perpendicular to the plane of the drawing, and the optical crystal axis runs parallel to the element axis. However, in contrast to the embodiments of FIGS. 3 and 4 a where the polarization-modulating optical elements 301, 401 are made preferably of one piece like in the case of crystalline material like crystalline quartz, the polarization-modulating optical element 421 comprises of four separate sector-shaped parts 422, 423, 424, 425 of an optically active crystal material which are held together by a mounting device 426 which can be made, e.g., of metal and whose shape can be described as a circular plate 427 with four radial spokes 428. The mounting is preferably opaque to the radiation which is entering the polarization-modulating optical element, thereby serving also as a spacer which separates the sector-shaped parts 422, 423, 424, 425 from each other. Of course the embodiment of the present invention according to FIG. 4 f is not intended to be limited to any specific shape and area of mounting device 426, which may also be omitted.
[0085] According to an alternate embodiment not illustrated in FIG. 4 f, incident light which is entering the polarization-modulating optical element can also be selectively directed onto the sector-shaped parts, e.g. by means of a diffractive structure or other suitable optical components.
[0086] The sector-shaped parts 422 and 424 have a first thickness d1 which is selected so that the parts 422 and 424 cause the plane of oscillation of linearly polarized axis-parallel light to be rotated by 90°+p·180°, where p represents an integer. The sector-shaped parts 423 and 425 have a second thickness d2 which is selected so that the parts 423 and 425 cause the plane of oscillation of linearly polarized axis-parallel light to be rotated by q·180°, where q represents an integer other than zero. Thus, when a bundle of axis-parallel light rays that are linearly polarized in the y-direction enters the polarization-modulating optical element 421, the rays that pass through the sector-shaped parts 423 and 425 will exit from the polarization-modulating optical element 421 with their plane of oscillation unchanged, while the rays that pass through the sector-shaped parts 422 and 424 will exit from the polarization-modulating optical element 421 with their plane of oscillation rotated into the x-direction. As a result of passing through the polarization-modulating optical element 421, the exiting light has a polarization distribution which is exactly tangential at the centerlines 429 and 430 of the sector-shaped parts 422, 423, 424, 425 and which approximates a tangential polarization distribution for the rest of the polarization-modulating optical element 421.
[0088] Of course the embodiment of the present invention according to FIG. 4 f is not intended to be limited to the shapes and areas and the number of sector-shaped parts exemplarily illustrated in FIG. 4 f, so that other suitable shapes (having for example but not limited to trapeze-shaped, rectangular, square, hexagonal or circular geometries) as well as more or less sector-shaped parts 422, 423, 424 and 425 can be used. Furthermore, the angles of rotation β1 and β2 provided by the sector-shaped parts 422, 423, 424, 425 (i.e. the corresponding thicknesses of the sector-shaped parts 422, 423, 424, 425) may be more generally selected to approximately conform to the expression |β2−β1|=(2n+1)·90°, with n representing an integer, for example to consider also relative arrangements where incoming light is used having a polarization plane which is not necessarily aligned with the x- or y-direction. With the embodiments as described in connection with FIG. 4 f it is also possible to approximate polarization distributions with a tangential polarization.
[0089] In order to produce a tangential polarization distribution from linearly polarized light with a wave length of 193 nm and a uniform direction of the oscillation plane of the electric field vectors of the individual light rays, one can use for example a polarization-modulating optical element of crystalline quartz with the design according to FIGS. 3 and 4 d. The specific rotation a of quartz for light with a wavelength of 193 nm is in the range of (325.2±0.5)°/mm, which was measured at a wavelength of 180 nm, or more precise it is 321.1°/mm at 21.6° C. The strength and effect of the optical activity is approximately constant within a small range of angles of incidence up to 100 mrad. An embodiment could for example be designed according to the following description: An amount of 276.75 μm, which approximately equals 90°/α, is selected for the minimum thickness dmin, if crystalline quartz is used Alternatively, the minimum thickness dmin can also be an integer multiple of this amount. The element diameter is 110 mm, with the diameter of the optically active part being somewhat smaller, for example 105 mm. The base surface is designed as a planar surface as illustrated in FIG. 3. The opposite surface has a thickness profile d(r,θ) in accordance with FIG. 4 d. The thickness profile is defined by the following mathematical relationships:
[0000] The above mentioned data are based exemplarily for a specific rotation α of (325.2±0.5)°/mm. If the specific rotation a changes to 321.1°/mm, the value at 193 nm and at a temperature of 21.60° C., the thickness profile will change as follows:
[0091] FIG. 5 schematically illustrates how a polarization-modulating optical element 501 with a thickness profile according to FIGS. 3 and 4 d converts the polarization distribution of an entering light bundle 513 with a uniformly oriented linear polarization distribution 517 into a tangential polarization 519 of an exiting light bundle 515. This can be visualized as follows: A linearly polarized light ray of the entering light bundle 513 which traverses the polarization-modulating optical element at a location of minimum thickness, for example at θ=180°, covers a distance of 90°/α inside the optically active crystal. This causes the oscillation plane of the electrical field vector to be rotated by 90°. On the other hand, a linearly polarized light ray traversing the polarization-modulating optical element 501 at a location with θ=45° covers a distance of 135°/α inside the optically active crystal, thus the oscillation plane of the electrical field vector of this ray is rotated by 135°. Analogous conclusions can be drawn for each light ray of the entering light bundle 513.
[0092] FIG. 6 schematically illustrates how an optical arrangement with a polarization-modulating optical element 601 with a thickness profile according to FIGS. 3 and 4 d in combination with a further polarization-modulating element 621 converts the polarization distribution of an entering light bundle 613 with a uniformly oriented linear polarization distribution 617 into a radial polarization 623 of an exiting light bundle 615. As explained in the context of FIG. 5, the polarization-modulating optical element 601 produces a tangential polarization distribution. A tangential polarization distribution can be converted into a radial polarization distribution by a 90′-rotation of the respective oscillation plane of each individual linearly polarized ray of the light bundle. There are several different possibilities to accomplish this with an optical arrangement according to FIG. 6. One possible concept is to arrange a planar-parallel plate of an optically active crystal as a further polarization-modulating element 621 in the light path, where the thickness of the plate is approximately 90°/αp with αp representing the specific rotation of the optically active crystal. As in the polarization-modulating element 601, the optical crystal axis of the planar parallel plate runs likewise parallel to the element axis. As another possible concept, the further polarization-modulating element 621 can be configured as a 90°-rotator that is assembled from two half-wave plates. A 90°-rotator consists of two half-wave plates of birefringent crystal material. Each plate has a slow axis associated with the direction of the higher refractive index and, perpendicular to the slow axis, a fast axis associated with the direction of the lower refractive index. The two half-wave plates are rotated relative to each other so their respective fast and slow axes are set at an angle of 45° from each other.
[0094] A tangential polarization distribution can also be produced with a polarization-modulating optical element that has a thickness profile in accordance with FIG. 4 e. The thickness profile in this embodiment of the invention has no discontinuities. As visualized in FIG. 7 a, the uniformly oriented polarization distribution 717 of the entering light bundle 713 is first transformed by the polarization-modulating optical element 701 into a linear polarization distribution 727 of an exiting light bundle 715. The one-half of the entering light bundle 713 that passes through the polarization-modulating optical element 701 in the azimuth range 0≦θ≦180° of the thickness profile shown in FIG. 4 e is converted so that the corresponding one-half of the exiting light bundle has a tangential polarization distribution. The other half, however, has a different, non-tangential polarization distribution 727. A further polarization-modulating optical element is needed in the light path in order to completely convert the polarization distribution 727 of the light bundle 715 exiting from the polarization-modulating optical element 701 into a tangential polarization distribution 719. The further polarization-modulating optical element is in this case configured as a planar-parallel plate 725 with a first half 729 and a second half 731. A plan view of the planar-parallel plate 725 is shown in FIG. 7 b. The first half 729 is made of an isotropic material that has no effect on the state of polarization of a light ray, while the second half 731 is designed as a half-wave plate. The planar-parallel plate 725 in the optical arrangement of FIG. 7 a is oriented so that a projection RA′ of the reference axis RA of the polarization-modulating optical element 701 onto the planar-parallel plate runs substantially along the separation line between the first half 729 and the second half 731. The slow axis LA of the birefringence of the half-wave plate is perpendicular to this separation line. Alternatively tangential polarization can also be achieved with a polarization-modulating optical element, having a thickness profile as given by FIG. 4 e, if the element is composed of two half wedge-shaped or helically shaped elements of crystalline quartz, wherein the optical activity of one element is clockwise and that of the other is counterclockwise. In this case no additional plane-parallel plate 725 is necessary, as it is in the embodiment of FIG. 7 a. In this embodiment preferably each wedge-shaped element has a constant screw-slope, but the slopes have different directions as shown in the profile of FIG. 4 e. Further, it is not necessary that the slopes of the geometrical thickness d have the same absolute values, it is sufficient if the slopes D of the optical effective thicknesses have the same absolute values. In this case the specific rotations α are different regarding absolute values for the two wedge-shaped elements which form the polarization-modulating optical element.
[0099] As an example, if the polarization-modulating optical element (as used e.g. in the optical system according to the present invention) is made of synthetic (crystalline) quartz, comprising a parallel plate or formed as a parallel plate, a thickness of 10 mm of such a plate will result in a change of polarization of 23.6 mrad/° C. or 23.6 mrad/K, equivalent to 1.35°/K, due to the linear temperature coefficient γ of the specific rotation a with γ=2.36 mrad/(mm*K). These data correspond to a wavelength of 193 nm. In such an embodiment, which is schematically shown in FIG. 9, the optical axis OA of the parallel plate 901 is directed parallel or approximately parallel to the propagation of the light (indicated by reference numeral 950) in the optical system. Approximately parallel means that the angle between the optical axis OA of the parallel plate 901 and the direction of the light propagating through the optical system is smaller than 200 mrad, preferably smaller than 100 mrad or even smaller than 50 mrad. Controlling the temperature of the plate 901 will result in a controlled change of polarization. If for example the temperature of the plate will be controlled in a range of about 20° C. to 40° C., the polarization angles can be controllably changed in a range of about ±13.5° for such a plate 901 made of quartz. This high sensitivity allows a control of the polarization distribution by temperature control. In such a case even a plane plate with a thickness d of about 0.1 mm up to 20 mm will become a polarization-modulating optical element 901, able to controllably adjust a polarization distribution by controlling the temperature of the plate 901. Preferably for synthetic (crystalline) quartz the thickness of the plate 901 is n*278.5 μm (n is any integer) which results in a rotation of a polarization plane of at least 90° for n=1 and 180° for n=2 and in general n*90°, for a wavelength of 193 nm at about 21.6° C. For a 90° rotation of the polarization plane the synthetic quartz should be at least 278.5 μm thick and for 180° at least 557.1 μm, for 270° the thickness should be 835.5 μm and for a 360° rotation of the polarization the thickness is 1.114 mm. The manufacturing tolerances regarding thickness are about ±2 μm. Thus the manufacturing tolerance results in an inaccuracy of the angle of the polarization plane of the light which passes the plate of about ±0.64° at about 21.6° C. and 193 nm. To this inaccuracy an additional inaccuracy caused by temperature fluctuation of the plate (or polarization-modulating optical element) have to be considered, which is given by the linear temperature coefficient γ of the specific rotation α with is γ=2.36 mrad/(mm*K)=0.15°/(mm*K).
[0100] The temperature control of the plate 901 can be done by closed-loop or open-loop control, using a temperature sensing device with at least one temperature sensor 902, 903 for determining the temperature of the plate 901 (or providing a temperature sensor value which is representative or equal to the temperature and/or the temperature distribution of the polarization-modulating optical element), at least a heater 904, 905, preferably comprising an infrared heater, for heating the plate by infrared radiation 906, and a control circuit 910 for controlling the at least one heater 904, 905. As an example of a temperature sensing device a infrared sensitive CCD-element with a projection optics may be used, wherein the projection optics images at least a part of the plate 901 onto the CCD-element such that a temperature profile of the viewed part of the plate 901 can be determined by the analysis of the CCD-element signals. The control circuit 910 may comprise a computer system 915 or may be connected to the computer or control system 915 of the microlithography projection system 833 (see FIG. 8). In a preferred embodiment of the temperature controlled plate 901 the thickness is chosen such that a rotation of the polarization of n*90°, n is any integer number, is achieved at a temperature T=(Tmax−Tmin)/2+Tmin, whereas Tmax and Tmin, are the maximum and minimum temperatures of the plate 901 (or in general the polarization-manipulating optical element). Preferably the heater or heating system (and also any cooling device like a Peltier element) is arranged such that it is not in the optical path of the microlithography projection system 833, or that it is not in the optical path of the light beam which is propagating through the optical system according to an embodiment of the present invention. Preferably the optical system with the polarization control system according to the present invention is used in a system with at least one additional optical element arranged between the polarization-modulating optical element and the predefined location in the optical system such that the light beam contacts the at least one additional optical element when propagating from the polarization-modulating optical element to the predefined location. The additional optical element preferably comprises a lens, a prism, a mirror, a refractive or a diffractive optical element or an optical element comprising linear birefringent material. Thus the optical system according to the present invention may form a part of a microlithography projection system 833.
[0107] In an additional embodiment of the present invention a polarization-modulating element or in general a polarizing optical element is temperature compensated to reduce any inaccuracy of the polarization distribution generated by the polarization-modulating element due to temperature fluctuations of said element, which for synthetic quartz material is given by the linear temperature coefficient γ of the specific rotation a for quartz (which is as already mentioned above γ=2.36 mrad/(mm*K)=0.15°/(mm*K)). The temperature compensation makes use of the realization that for synthetic quartz there exist one quartz material with a clockwise and one quartz material with a counterclockwise optical activity (R-quartz and L-quartz). Both, the clockwise and the counterclockwise optical activities are almost equal in magnitude regarding the respective specific rotations α. The difference of the specific rotations is less than 0.3%. Whether the synthetic quartz has clockwise (R-quartz) or counterclockwise (L-quartz) optical activity dependents on the seed-crystal which is used in the manufacturing process of the synthetic quartz.
[0108] R- and L-quartz can be combined for producing a thermal or temperature compensated polarization-modulating optical element 911 as shown in FIG. 11. Regarding the change of the state of polarization such a temperature compensated polarization-modulating optical element 911 is equivalent to a plane plate of synthetic quartz of thickness d. For example, two plane plates 921 and 931 are arranged behind each other in the direction 950 of the light which is propagating through the optical system which comprises the temperature compensated polarization-modulating optical element 911. The arrangement of the plates is such that one plate 931 is made of R-quartz with thickness dR, and the other 921 is made of L-quartz with thickness dL, and |dR−dL|=d. If the smaller thickness of dR and dL (min (dR, dL)) is larger than d or min (dR, dL)>d, which in most cases is a requirement due to mechanical stability of the optical element, then the temperature dependence of the polarization state becomes partly compensated, meaning that the temperature dependence of the system of R-quartz and L-quartz plates is smaller than γ=2.36 mrad/(mm*K)*d=0.15°/(mm*K)*d, wherein d is the absolute value of the difference of the thicknesses of the two plates d=|dR−dL|. The following example demonstrates this effect. A R-quartz plate 931 with a thickness of e.g. dR=557.1 μm (resulting in a 180° clockwise change of the exiting polarization plane compared to the incident polarization plane) is combined with a L-quartz plate 921 with a thickness of dL=557.1 μm+287.5 μm (resulting in a 270° counterclockwise change of the exiting polarization plane compared to the incident polarization). This result in a 90° counterclockwise change of the polarization plane after the light pass both plane plates 921, 931, corresponding to a 270° clockwise change of the polarization plane if just a R-quartz plate would be used. In this case the temperature compensation is not fully achieved, but it is reduced to value of about 0.04°/K if both plates are used, compared to 0.13°/K if just a R-quartz plate of dR=557.1 μm+287.5 μm would be used. This is a significant reduction of temperature dependency, since even if the temperature will change by 10° C. the change of the polarization plane is still smaller than 1°.
[0109] In general any structured polarization-modulating optical element made of R- or L-quartz, like e.g. the elements as described in connection with FIGS. 3 and 4 a can be combined with a plane plate of the respective other quartz type (L- or R-quartz) such that the combined system 911 will have a reduced temperature dependence regarding the change of the polarization. Instead of the plane plate also a structured optical element made of the respective other quartz type may be used such that in FIG. 11 the shown plates 921 and 931 can be structured polarization-modulating optical elements as mentioned in this specification, having specific rotations of opposite signs, changing the state of polarization clockwise and counterclockwise.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS2473857 *Dec 5, 1946Jun 21, 1949Burchell Holloway CorpApparatus for insertion in color display devices utilizing polarized light for securing changing saturation of specific hues in fixed zones as vewed by observersUS3438692 *Mar 8, 1965Apr 15, 1969Bell Telephone Labor IncBirefringent device for forming multiple imagesUS3484714 *Dec 16, 1964Dec 16, 1969American Optical CorpLaser having a 90 polarization rotator between two rods to compensate for the effects of thermal gradientsUS3630598 *Jan 2, 1970Dec 28, 1971Xerox CorpOptical demodulation filterUS3719415 *Sep 22, 1971Mar 6, 1973Bell Telephone Labor IncRadial and tangential polarizersUS3758201 *Jul 15, 1971Sep 11, 1973American Optical CorpOptical system for improved eye refractionUS3892469 *Feb 1, 1974Jul 1, 1975Hughes Aircraft CoElectro-optical variable focal length lens using optical ring polarizerUS3892470 *Feb 1, 1974Jul 1, 1975Hughes Aircraft CoOptical device for transforming monochromatic linearly polarized light to ring polarized lightUS3957375 *Jul 23, 1974May 18, 1976The United States Of America As Represented By The United States Energy Research And Development AdministrationVariable thickness double-refracting plateUS4175830 *Dec 22, 1977Nov 27, 1979Marie G R PWave mode converterUS4235517 *Feb 10, 1978Nov 25, 1980Marie Georges RPower laser emitting plasma confining wave beamUS4272158 *Mar 2, 1979Jun 9, 1981Coherent, Inc.Broadband optical diode for a ring laserUS4286843 *May 14, 1979Sep 1, 1981Reytblatt Zinovy VPolariscope and filter thereforUS4370026 *Sep 8, 1980Jan 25, 1983Thomson-CsfIlluminating device for providing an illumination beam with adjustable distribution of intensity and a pattern-transfer system comprising such a deviceUS4712880 *Aug 25, 1986Dec 15, 1987Fujitsu LimitedPolarization rotation compensator and optical isolator using the sameUS4755027 *Jun 30, 1986Jul 5, 1988Max-Planck-Gesellschaft Zur Forderung Der Wissenschaften E.V.Method and device for polarizing light radiationUS5253110 *Nov 24, 1992Oct 12, 1993Nikon CorporationIllumination optical arrangementUS5300972 *Feb 5, 1993Apr 5, 1994Mitsubishi Denki Kabushiki KaishaProjection exposure apparatusUS5382999 *Dec 10, 1993Jan 17, 1995Mitsubishi Denki Kabushiki KaishaOptical pattern projecting apparatusUS5436761 *Aug 26, 1994Jul 25, 1995Mitsubishi Denki Kabushiki KaishaProjection exposure apparatus and polarizerUS5442184 *Dec 10, 1993Aug 15, 1995Texas Instruments IncorporatedSystem and method for semiconductor processing using polarized radiant energyUS5453814 *Apr 13, 1994Sep 26, 1995Nikon Precision Inc.Illumination source and method for microlithographyUS5459000 *Oct 4, 1993Oct 17, 1995Canon Kabushiki KaishaImage projection method and device manufacturing method using the image projection methodUS5471343 *Nov 29, 1993Nov 28, 1995Olympus Optical Co., Ltd.Imaging deviceUS5673103 *Aug 23, 1996Sep 30, 1997Kabushiki Kaisha ToshibaExposure apparatus and methodUS5677755 *Oct 28, 1994Oct 14, 1997Hitachi, Ltd.Method and apparatus for pattern exposure, mask used therefor, and semiconductor integrated circuit produced by using themUS5692082 *Oct 30, 1995Nov 25, 1997Fujitsu LimitedLaser diode module and depolarizerUS5719704 *Oct 27, 1995Feb 17, 1998Nikon CorporationProjection exposure apparatusUS5815247 *Sep 21, 1995Sep 29, 1998Siemens AktiengesellschaftAvoidance of pattern shortening by using off axis illumination with dipole and polarizing aperturesUS5867315 *Jul 30, 1996Feb 2, 1999Pioneer Electronic CorporationCrystal optic lens and an optical system for an optical pickup deviceUS5933219 *Apr 19, 1995Aug 3, 1999Canon Kabushiki KaishaProjection exposure apparatus and device manufacturing method capable of controlling polarization directionUS6191880 *Jul 14, 1999Feb 20, 2001Carl-Zeiss-StiftungRadial polarization-rotating optical arrangement and microlithographic projection exposure system incorporating said arrangementUS6246506 *Jul 12, 2000Jun 12, 2001Fujitsu LimitedOptical display device having a reflection-type polarizerUS6252712 *Feb 19, 1999Jun 26, 2001Carl-Zeiss-StiftungOptical system with polarization compensatorUS6258433 *Aug 3, 1999Jul 10, 2001Matsushita Electric Industrial Co., Ltd.Optical recording mediumUS6285443 *May 20, 1999Sep 4, 2001Carl-Zeiss-StiftungIlluminating arrangement for a projection microlithographic apparatusUS6310679 *Jun 14, 1999Oct 30, 2001Nikon CorporationProjection exposure method and apparatusUS6324203 *Jun 12, 1998Nov 27, 2001Nikon CorporationLaser light source, illuminating optical device, and exposure deviceUS6392800 *Dec 7, 2000May 21, 2002Carl-Zeiss-StiftungRadial polarization-rotating optical arrangement and microlithographic projection exposure system incorporating said arrangementUS6404482 *Mar 25, 1999Jun 11, 2002Nikon CorporationProjection exposure method and apparatusUS6483573 *Feb 14, 2000Nov 19, 2002Carl-Zeiss-StiftungProjection exposure system and an exposure method in microlithographyUS6553156 *Jun 30, 2000Apr 22, 2003Oplink Communications, Inc.Optical isolators with ultra-low polarization mode dispersionUS6721258 *Jun 21, 2000Apr 13, 2004Citizen Watch Co., Ltd.Optical device for super-resolutionUS6774984 *May 15, 2002Aug 10, 2004Carl Zeiss Semiconductor Manufacturing Technologies, AgOptical imaging system with polarizer and a crystalline-quartz plate for use therewithUS6885502 *May 9, 2002Apr 26, 2005Carl-Zeiss-StiftungRadial polarization-rotating optical arrangement and microlithographic projection exposure system incorporating said arrangementUS6934009 *May 30, 2002Aug 23, 2005Canon Kabushiki KaishaIllumination apparatus, illumination-controlling method, exposure apparatus, device fabricating methodUS6943941 *Feb 27, 2003Sep 13, 2005Asml Netherlands B.V.Stationary and dynamic radial transverse electric polarizer for high numerical aperture systemsUS6965484 *Jul 24, 2003Nov 15, 2005Massachusetts Institute Of TechnologyOptical imaging systems and methods using polarized illumination and coordinated pupil filterUS6970233 *Dec 3, 2003Nov 29, 2005Texas Instruments IncorporatedSystem and method for custom-polarized photolithography illuminationUS7009686 *Sep 19, 2003Mar 7, 2006Canon Kabushiki KaishaExposure methodUS7113260 *Oct 11, 2005Sep 26, 2006Carl Zeiss Smt AgProjection exposure system for microlithography and method for generating microlithographic imagesUS7126667 *Mar 17, 2006Oct 24, 2006Canon KkExposure apparatus and methodUS7126673 *Mar 31, 2005Oct 24, 2006Canon Kabushiki KaishaIllumination optical system and exposure apparatus having the sameUS7170679 *Sep 18, 2003Jan 30, 2007Vision Quest Lighting, Inc.Optically active color filterUS7199864 *Jan 23, 2006Apr 3, 2007Carl-Zeiss Smt AgPolarization rotator and a crystalline-quartz plate for use in an optical imaging systemUS7199936 *Mar 21, 2006Apr 3, 2007Intel CorporationMethod and apparatus for polarizing electromagnetic radiationUS7209289 *Sep 27, 2005Apr 24, 2007Metrologic Instruments, Inc.Illumination apparatus with polarizing elements for beam shapingUS7239375 *Jul 17, 2006Jul 3, 2007Canon Kabushiki KaishaIllumination apparatus, exposure apparatus and device manufacturing methodUS7265816 *Jun 20, 2005Sep 4, 2007Canon Kabushiki KaishaIllumination optical system, exposure apparatus, and device manufacturing method with modified illumination generatorUS7292315 *Aug 20, 2004Nov 6, 2007Asml Masktools B.V.Optimized polarization illuminationUS7345740 *Apr 8, 2005Mar 18, 2008Asml Netherlands B.V.Polarized radiation in lithographic apparatus and device manufacturing methodUS7345741 *Jun 2, 2005Mar 18, 2008Canon Kabushiki KaishaIllumination optical system and exposure apparatusUS7375887 *Nov 24, 2004May 20, 2008Moxtek, Inc.Method and apparatus for correcting a visible light beam using a wire-grid polarizerUS7386830 *Aug 23, 2005Jun 10, 2008Kabushiki Kaisha ToshibaMethod for designing an illumination light source, method for designing a mask pattern, method for manufacturing a photomask, method for manufacturing a semiconductor device and a computer program productUS7408616 *Sep 27, 2004Aug 5, 2008Carl Zeiss Smt AgMicrolithographic exposure method as well as a projection exposure system for carrying out the methodUS7408622 *Nov 19, 2004Aug 5, 2008Carl Zeiss Smt AgIllumination system and polarizer for a microlithographic projection exposure apparatusUS7411656 *Jan 24, 2006Aug 12, 2008Carl Zeiss Smt AgOptically polarizing retardation arrangement, and a microlithography projection exposure machineUS7414786 *Jan 12, 2005Aug 19, 2008University Of RochesterSystem and method converting the polarization state of an optical beam into an inhomogeneously polarized stateUS7433046 *Sep 3, 2004Oct 7, 2008Carl Ziess Meditec, Inc.Patterned spinning disk based optical phase shifter for spectral domain optical coherence tomographyUS7436491 *Dec 12, 2005Oct 14, 2008Kabushiki Kaisha ToshibaExposure system, exposure method and method for manufacturing a semiconductor deviceUS7445883 *Aug 14, 2006Nov 4, 2008Asml Holding N.V.Lithographic printing with polarized lightUS7446858 *Oct 11, 2005Nov 4, 2008Nikon CorporationExposure method and apparatus, and method for fabricating deviceUS7499148 *Jul 2, 2004Mar 3, 2009Renesas Technology Corp.Polarizer, projection lens system, exposure apparatus and exposing methodUS7511884 *Jul 25, 2005Mar 31, 2009Asml Netherlands B.V.Stationary and dynamic radial transverse electric polarizer for high numerical aperture systemsUS7515248 *Nov 5, 2007Apr 7, 2009Nikon CorporationIllumination optical system, exposure apparatus, and exposure method with polarized state detection result and adjustmentUS20020149847 *Apr 11, 2002Oct 17, 2002Nikon CorporationOptical filter and optical device provided with this optical filterUS20020163629 *May 7, 2002Nov 7, 2002Michael SwitkesMethods and apparatus employing an index matching mediumUS20030086070 *Jun 6, 2002May 8, 2003Doo-Hoon GooSingle aperture optical system for photolithography systemsUS20030095241 *Nov 15, 2002May 22, 2003Asml Netherlands B.V.Interferometric alignment system for use in vacuum-based lithographic apparatusUS20040169924 *Feb 27, 2003Sep 2, 2004Asml Netherlands, B.V.Stationary and dynamic radial transverse electric polarizer for high numerical aperture systemsUS20050164522 *Mar 24, 2003Jul 28, 2005Kunz Roderick R.Optical fluids, and systems and methods of making and using the sameUS20050195480 *Jan 12, 2005Sep 8, 2005Brown Thomas G.System and method converting the polarization state of an optical beam into an inhomogeneously polarized stateUS20060077370 *Oct 12, 2004Apr 13, 2006Asml Netherlands B.V.Lithographic apparatus, device manufacturing methodUS20060119826 *Jan 23, 2006Jun 8, 2006Carl Zeiss Smt AgPolarization rotator and a crystalline-quartz plate for use in an optical imaging systemUS20060158624 *Dec 28, 2005Jul 20, 2006Nikon CorporationBeam transforming element, illumination optical apparatus, exposure apparatus, and exposure methodUS20060170901 *Feb 6, 2006Aug 3, 2006Nikon CorporationPolarization-modulating element, illumination optical apparatus, exposure apparatus, and exposure methodUS20060221453 *Mar 15, 2006Oct 5, 2006Carl Zeiss Smt AgFly's eye condenser and illumination system therewithUS20070139636 *Feb 16, 2007Jun 21, 2007Carl Zeiss Smt AgPolarization rotator and a crystalline-quartz plate for use in an optical imaging systemUS20070146676 *Dec 26, 2006Jun 28, 2007Nikon CorporationMethod of adjusting lighting optical device, lighting optical device, exposure system, and exposure methodUS20070222962 *Jul 21, 2005Sep 27, 2007Nikon CorporationIllumination Optical Equipment, Exposure System and MethodUS20090073441 *Oct 29, 2008Mar 19, 2009Nikon CorporationPolarization-modulating element, illumination optical apparatus, exposure apparatus, and exposure methodUS20090115989 *Oct 30, 2006May 7, 2009Hirohisa TanakaLighting optical system, exposure system, and exposure methodUS20090128796 *Oct 8, 2008May 21, 2009Nikon CorporationIllumination optics apparatus, exposure method, exposure apparatus, and method of manufacturing electronic deviceUS20090147235 *Jan 27, 2009Jun 11, 2009Nikon CorporationBeam transforming element, illumination optical apparatus, exposure apparatus, and exposure method with two optical elements having different thicknessesUS20090284729 *Jul 17, 2009Nov 19, 2009Nikon CorporationIllumination optical apparatus and projection exposure apparatusUS20100141921 *Feb 5, 2010Jun 10, 2010Nikon CorporationOptical system, exposure system, and exposure methodUS20100141926 *Feb 5, 2010Jun 10, 2010Nikon CorporationOptical system,exposure system, and exposure methodUS20100142051 *Feb 5, 2010Jun 10, 2010Nikon CorporationOptical system, exposure system, and exposure method* Cited by examinerReferenced byCiting PatentFiling datePublication dateApplicantTitleUS7916391Mar 4, 2005Mar 29, 2011Carl Zeiss Smt GmbhApparatus 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element, illumination optical apparatus, exposure apparatus, and exposure methodUS9423697May 8, 2013Aug 23, 2016Nikon CorporationIllumination optical apparatus and projection exposure apparatusUS9423698May 15, 2015Aug 23, 2016Nikon CorporationIllumination optical apparatus and projection exposure apparatusUS9429848 *Oct 29, 2008Aug 30, 2016Nikon CorporationPolarization-modulating element, illumination optical apparatus, exposure apparatus, and exposure methodUS9470982Jul 2, 2013Oct 18, 2016Carl Zeiss Smt GmbhPolarization-modulating optical elementUS9581911Jul 2, 2013Feb 28, 2017Carl Zeiss Smt GmbhPolarization-modulating optical elementUS9588432May 9, 2013Mar 7, 2017Nikon CorporationIllumination optical apparatus having deflecting member, lens, polarization member to set polarization in circumference direction, and optical integratorUS20060203214 *Apr 26, 2006Sep 14, 2006Nikon CorporationIllumination optical apparatus and projection exposure apparatusUS20060291057 *May 25, 2006Dec 28, 2006Damian FiolkaPolarization-modulating optical elementUS20070081114 *Jan 14, 2005Apr 12, 2007Damian FiolkaPolarization-modulating optical elementUS20070146676 *Dec 26, 2006Jun 28, 2007Nikon CorporationMethod of adjusting lighting optical device, lighting optical device, exposure system, and exposure methodUS20080024747 *Sep 20, 2007Jan 31, 2008Nikon CorporationExposure method and apparatus, and method for fabricating deviceUS20080316459 *Aug 29, 2008Dec 25, 2008Carl Zeiss Smt AgPolarization-modulating optical elementUS20080316598 *Aug 28, 2008Dec 25, 2008Carl Zeiss Smt AgPolarization-modulating optical elementUS20090027623 *Jan 30, 2008Jan 29, 2009Sony CorporationOptical apparatus and projection display systemUS20090073414 *Oct 29, 2008Mar 19, 2009Nikon CorporationPolarization-modulating element, illumination optical apparatus, exposure apparatus, and exposure methodUS20090073441 *Oct 29, 2008Mar 19, 2009Nikon CorporationPolarization-modulating element, illumination optical 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Cited by examinerClassifications U.S. Classification355/71, 362/19, 359/486.03International ClassificationG02B5/30, G02F1/01, F21V9/14, G02B1/08, G03F7/20, G03B27/54, G02B27/28Cooperative ClassificationG02B5/3025, G02F1/0147, G03F7/70341, G02B5/3075, G03F7/70566, G02B27/286, G02F1/0136, G03F7/70058, G02B5/3083, G02B1/08European ClassificationG03F7/70L4D, G03F7/70F24, G02B5/30P4, G02B27/28C, G02F1/01P, G02B5/30P, G02B1/08Legal EventsDateCodeEventDescriptionSep 16, 2008ASAssignmentOwner name: CARL ZEISS SMT AG, GERMANYFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FIOLKA, DAMIAN;DEGUENTHER, MARKUS;REEL/FRAME:021534/0622Effective date: 20060908Jan 18, 2011ASAssignmentOwner name: CARL ZEISS SMT GMBH, GERMANYFree format text: A MODIFYING CONVERSION;ASSIGNOR:CARL ZEISS SMT AG;REEL/FRAME:025763/0367Effective date: 20101014Jul 30, 2013CCCertificate of correctionMay 19, 2016FPAYFee paymentYear of fee payment: 4RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - 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