POLARIZATION-MODULATING OPTICAL ELEMENT
The invention relates to a projection system, comprising a radiation source, an illumination system operable to illuminate a structured mask, and a projection objective for projecting an image of the mask structure onto a light-sensitive substrate, wherein said projection system comprises 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 comprising a temperature compensated 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 or parallel to said preferred direction; said temperature compensated polarization-modulating optical element comprising a first and a second polarization-modulating optical element, the first and/or the second polarization-modulating optical element comprising solid and/or liquid optically active material and a profile of effective optical thickness, wherein the effective optical thickness varies at least as a function of one coordinate different from the preferred coordinate of the coordinate system, in addition or alternative the first and/or the second polarization-modulating optical element comprises solid and/or liquid optically active material, wherein the effective optical thickness is constant as a function of at least one coordinate different from the preferred coordinate of the coordinate system; wherein the first polarization-modulating optical element comprises optically active material with a specific rotation of opposite sign compared to the optically active material of the second polarization-modulating optical element.
1 . (canceled)
2 . An apparatus which illuminates a surface to be illuminated with radiation from a radiation source, the apparatus comprising:
an optical member having a first portion of a first thickness along an optical axis direction of the apparatus and a second portion of a second thickness along the optical axis direction of the apparatus, wherein
the first and second portion thicknesses are different from each other, and the optical member is made of an optical material with optical activity.
3 . The apparatus according to claim 2 , wherein the optical member includes a first basic element and a second basic element.
4 - 7 . (canceled)
8 . The apparatus according to claim 3 , wherein the first and second basic elements are arranged in a plane in an illumination path of the apparatus.
9 - 14 . (canceled)
15 . The apparatus according to claim 3 , wherein the first basic element and the second basic element are integrally formed.
16 . (canceled)
17 . The apparatus according to claim 2 , further comprising:
a first optical unit including a first optical axis;
a second optical unit including a second optical axis which crosses the first optical axis, the first optical unit arranged in an illumination path between the radiation source and the second optical unit;
a third optical unit including a third optical axis which crosses the second optical axis, and the third optical unit is arranged in an illumination path between the second optical unit and the surface to be illuminated, wherein the second optical unit includes the optical member.
18 . The apparatus according to claim 17 , wherein the optical member includes a first basic element and a second basic element.
19 - 21 . (canceled)
22 . The apparatus according to claim 17 , wherein the first basic element and the second basic element are integrally formed.
23 . The apparatus according to claim 17 , wherein the third optical unit includes a folding mirror.
24 . The apparatus according to claim 17 , wherein the second optical unit includes a polarization state converter.
25 - 26 . (canceled)
27 . The apparatus according to claim 2 , wherein a polarization state of the beam from the optical member is set based on an influence of a second optical member in an illumination path between the light source and a substrate arranged surface.
28 - 75 . (canceled)
76 . An apparatus which illuminates a surface to be illuminated with radiation from a radiation source, the apparatus comprising:
a polarization state converter arranged in an illumination path;
a first crystal optical element having a first thickness along an optical axis direction; and
a second crystal optical element having a second thickness along an optical axis direction;
wherein the first and second crystal optical elements are arranged in a plane disposed in an illumination path of the apparatus.
77 - 91 . (canceled)
92 . An exposure apparatus comprising the apparatus as defined in claim 76 , wherein the exposure apparatus illuminates a predetermined pattern, and projects an image of the predetermined pattern onto a photosensitive substrate on the surface to be illuminated.
93 . The exposure apparatus according to claim 92 , wherein an illumination pupil distribution on or near an illumination pupil of the apparatus is a distribution in at least a part of a predetermined annular region centered around an optical axis of the apparatus.
94 . The exposure apparatus according to claim 92 , wherein a polarization state of the beam from the first and second crystal optical elements is set based on an influence of an optical member disposed in an illumination path between the light source and the photosensitive substrate on the surface to be illuminated.
95 . (canceled)
96 . The exposure apparatus according to claim 92 , wherein a polarization state of the beam at an illumination pupil is set so that light illuminating the photosensitive substrate is in a polarization state in which a principal component is s-polarized light.
97 - 108 . (canceled)
109 . An apparatus which illuminates a surface to be illuminated with radiation from a radiation source, the apparatus comprising:
an optical element made of an optical material with optical activity, an optic axis of the optical material of the optical element being aligned along an optical axis of the apparatus.
110 - 114 . (canceled)
115 . The apparatus according to claim 110 , wherein the first and second basic elements are arranged in a plane which is disposed in an illumination path of the apparatus.
116 - 122 . (canceled)
123 . An exposure apparatus comprising the apparatus as defined in claim 109 , which illuminates a predetermined pattern and projects the predetermined pattern onto a photosensitive substrate.
124 . The exposure apparatus according to claim 123 , wherein an illumination pupil distribution on or near an illumination pupil of the apparatus is a distribution in at least a part of a predetermined annular region, which is a predetermined annular region centered around an optical axis of the apparatus.
125 . The exposure apparatus according to claim 124 , wherein a polarization state of the beam at the illumination pupil is set based on an influence of an optical member disposed in an optical path between the light source and the photosensitive substrate.
126 . (canceled)
127 . The exposure apparatus according to claim 124 , wherein a polarization state of the beam at the illumination pupil is set so that light illuminating the photosensitive substrate is in a polarization state in which a principal component is s-polarized light.
128 - 219 . (canceled)
220 . A polarization transforming element used in an illumination optical apparatus that illuminates a predetermined pattern on the basis of a beam from a light source, comprising:
a plurality of optical members with different thicknesses, each optical member made of an optical material with optical activity,
wherein each of the plurality of optical member provides a predetermined polarization state on a predetermined surface according to the thickness of the optical member.
221 . The polarization transforming element according to claim 220 , wherein the predetermined surface is an illumination pupil plane of the illumination optical apparatus or a plane near the illumination pupil plane.
222 . The polarization transforming element according to claim 221 , wherein a predetermined light intensity distribution of an annular shape or a multipole shape positioned in a predetermined annular region formed on the predetermined surface, and wherein the predetermined annular region is centered around a predetermined point on the predetermined surface.
223 . (canceled)
224 . The polarization transforming element according to claim 221 , wherein the predetermined polarization state has a polarization state in which a principal component is linearly polarized light having a direction of polarization along a circumferential direction of a predetermined annular region, which is a predetermined annular region centered around a predetermined point on the predetermined surface.
225 . (canceled)
226 . The polarization transforming element according to claim 224 , wherein the optical members are made of crystalline quartz.
227 . (canceled)
228 . The polarization transforming element according to claim 220 , wherein the optical members are made of an optical material with optical activity.
229 . An illumination optical apparatus for illuminating a surface to be illuminated, based on a beam from a light source, comprising: the polarization transforming element as defined in claim 220 , for transforming the beam from the light source in order to form a predetermined polarization distribution on or near an illumination pupil of the illumination optical apparatus.
230 - 231 . (canceled)
232 . The illumination optical apparatus according to claim 229 , wherein the polarization state of the beam from the polarization transforming element is so set that light illuminating the surface to be illuminated is in a polarization state in which a principal component is s-polarized light.
233 - 238 . (canceled)
239 . The beam transforming element according to claim 145 , wherein an optical axis of the optical material of the first basic element is aligned along a traveling direction of the incident beam, and wherein an optical axis of the optical material of the second basic element is aligned along the traveling direction of the incident beam.
240 . (canceled)
241 . The polarization transforming element according to claim 220 , wherein each optical axis of the optical material of the optical member is aligned along a traveling direction of the incident beam.
242 . The apparatus of claim 2 , further comprising a light source and one or more optical elements arranged to direct radiation from the light source to the surface to be illuminated during operation of the apparatus, the one or more optical elements defining a pupil plane between the light source and the surface to be illuminated, wherein the optical member is arranged at the pupil plane.
243 . The apparatus of claim 76 , further comprising a light source and one or more optical elements arranged to direct radiation from the light source to the surface to be illuminated during operation of the apparatus, the one or more optical elements defining a pupil plane between the light source and the surface to be illuminated, wherein the first and second crystal optical elements are arranged at the pupil plane.
244 . The apparatus of claim 109 , further comprising a light source and one or more additional optical elements arranged to direct radiation from the light source to the surface to be illuminated during operation of the apparatus, the one or more optical elements defining a pupil plane between the light source and the surface to be illuminated, wherein the optical element made of an optical material with optical activity is arranged at the pupil plane.
245 . An illumination optical apparatus that illuminates a predetermined pattern, comprising:
a light source;
one or more optical elements; and
the polarization transforming element of claim 220 ,
wherein the one or more optical elements define a pupil plane between the light source and the predetermined pattern and the polarization transforming element is arranged at the pupil plane.