A projection lens of an EUV-lithographic projection exposure system with at least two reflective optical elements each comprising a body and a reflective surface for projecting an object field on a reticle onto an image field on a substrate if the projection lens is exposed with an exposure power of
A projection lens of an EUV-lithographic projection exposure system with at least two reflective optical elements each comprising a body and a reflective surface for projecting an object field on a reticle onto an image field on a substrate if the projection lens is exposed with an exposure power of EUV light, wherein the bodies of at least two reflective optical elements comprise a material with a temperature dependent coefficient of thermal expansion which is zero at respective zero cross temperatures, and wherein the absolute value of the difference between the zero cross temperatures is more than 6K.
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1. A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising: at least first and second reflective optical elements (Mm, Mn);said reflective optical elements (Mm, Mn) having respecti
1. A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising: at least first and second reflective optical elements (Mm, Mn);said reflective optical elements (Mm, Mn) having respective bodies (MBm, MBn) defining respective reflective surfaces (MSm, MSn) for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with the exposure power of the EUV light reflected from said reticle when illuminated by said illumination system;said bodies (MBm, MBn) including a material having a temperature dependent coefficient of thermal expansion which is zero at respective zero cross temperatures (T0m, T0n);said zero cross temperatures (T0m, T0n) having a difference between each other of which the absolute value is greater than 6K, expressed as abs(T0m−T0n)>6K; and,said projection lens being configured to be exposed with an exposure power of more than 8 W of EUV light at a wavelength lying in a wavelength range of less than 50 nm. 2. The projection lens of claim 1 further comprising: at least four or six of reflective optical element Mi;the projection lens being configured to be exposed with an exposure power of more than 10 W; and,said zero cross temperatures (T0m, T0n) having a difference between each other of which the absolute value is greater than 8K, expressed as abs(T0m−T0n)>8K. 3. The projection lens of claim 1 further comprising: a support structure configured to passively or actively support said reflective optical elements Mi and at least a part of said support structure is at a reference temperature Tref;a heater configured to heat at least one of said bodies (MBm, MBn) which include the material with the temperature dependent coefficient of thermal expansion which is zero at respective zero cross temperatures (T0m, T0n); and,a temperature control system configured to control the temperature of at least one of saidheatable bodies (MBm, MBn) to a temperature Tk. 4. The projection lens of claim 3, wherein: without operation of the heater, the exposure of the reflective surfaces (MSm, MSn) of the respective bodies (MBm, MBn) with EUV light being reflected by the illuminated reticle and including a spatial distribution of angular, polarization and intensity in accordance with an illumination setting, resulting in temperature distributions ΔTn(x,y,z)=(Tn(x,y,z)−TRef), ΔTm(x,y,z)=(Tm(x,y,z)−TRef) of the bodies (MBm, MBn) relative to the reference temperature TRef with respective average and maximum temperatures ΔTnav, ΔTmav and ΔTnmax and ΔTmmax; and,at least one zero cross temperatures (T0m, T0n) is higher than the maximum of the highest reference temperature TRef and the respective average or maximum temperature ΔTmav+Tref or ΔTmmax+Tref, ΔTnav+Tref or ΔTnmax+Tref, based on the respective spatial temperature distribution ΔTm(x,y,z), ΔTn(x,y,z), expressed as T0m>max(TRef, ΔTmav+Tref), T0m>max(TRef, ΔTmmax+Tref) or T0n>max(TRef, ΔTnav+TRef), T0n>max(TRef, ΔTnmax+Tref). 5. The projection lens of claim 4, wherein: the materials comprising the zero cross temperatures (T0m, T0n) vary regarding their real value of the zero cross temperature due to manufacturing, resulting in respective manufacturing tolerances (ΔT0m, ΔT0n) such that the respective real values of the zero cross temperatures are within the intervals T0m±ΔT0m and T0n±ΔT0n; and,at least one zero cross temperatures (T0m, T0n) is higher than the maximum of the highest reference temperature TRef and the respective average or maximum temperature ΔTmav+TRef or ΔTmmax+TRef, ΔTnav+TRef or ΔTnmax+TRef, based on the respective spatial temperature distribution ΔTm(x,y,z), ΔTn(x,y,z), increased by the absolute value of the respective manufacturing tolerances ΔT0m, ΔT0n, expressed as T0m>max(TRef, ΔTmav+TRef)+|ΔT0m|, T0m>max(TRef, ΔTmmax+TRef)+|ΔT0m| or T0n>max(TRef, ΔTnav+TRef)+|ΔT0n|, T0n>max(TRef, ΔTnmax+TRef)+|ΔT0n|. 6. The projection lens of claim 4, wherein the temperature Tk of the at least one heated body (MBm, MBn) is within an interval of ±5K, better ±2K, centered around the respective zero cross temperature (T0m, T0n). 7. The projection lens of claim 3, wherein at a time before the projection lens is exposed with the exposure power of the EUV light, the temperature Tk of the at least one heated body (MBn, MBm) is controlled to its value by heating the heater with a first heating power. 8. The projection lens of claim 7, wherein at the time while exposing the projection lens with the exposure power of the EUV light, the heating power of the heater is lower than the first heating power. 9. The projection lens of claim 7, wherein the temperature control system controls the temperature Tk such that the heating power of the heater, heating the at least one body (MBm, MBn), and the exposure power of the EUV light absorbed by the at least one heated body (MBm, MBn) is constant in time. 10. The projection lens of claim 3, wherein the at least one heated body (MBm, MBn) is connected to an actuator for translational movement of the body. 11. The projection lens of claim 3, wherein the heater for heating the at least one of the bodies (MBm, MBn) comprises heating elements selected from the group consisting of IR light emitting diodes, Peltier elements, optical fibers, light guide rods and IR lasers. 12. The projection lens of claim 11, wherein the heating elements are arranged in one dimension or in two dimensions at predefined spatial coordinates, forming a grid structure. 13. The projection lens of claim 11, wherein the heating elements emitting or guiding IR radiation comprising an optical arrangement to configure the IR radiation, the optical arrangement comprises arrangement elements selected from the group consisting of collimator, focusing lens, adjustable lens, mirror and diffractive optical element, wherein the arrangement elements may be tiltable around at least on axis. 14. The projection lens of claim 11, wherein the at least one of the bodies (MBm, MBn) comprises a modification in or on the mirror body, the modification is selected from the group consisting of recess, blind hole, defined surface roughness, diffractive structure, spherical protrusion, spherical recess and surface curvature. 15. An EUV-lithographic projection exposure system comprising: a reticle;an illumination system for illuminating the reticle;a projection lens including:at least first and second reflective optical elements (Mm, Mn);said reflective optical elements (Mm, Mn) having respective bodies (MBm, MBn) defining respective reflective surfaces (MSm, MSn) for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with the exposure power of the EUV light reflected from said reticle when illuminated by said illumination system;said bodies (MBm, MBn) including a material having a temperature dependent coefficient of thermal expansion which is zero at respective zero cross temperatures (T0m, T0n);said zero cross temperatures (T0m, T0n) having a difference between each other of which the absolute value is greater than 6K, expressed as abs(T0m−T0n)>6K; and,said projection lens being configured to be exposed with an exposure power of more than 8 W of EUV light at a wavelength lying in a wavelength range of less than 50 nm. 16. A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising: at least first and second reflective optical elements (Mm, Mn);said reflective optical elements (Mm, Mn) having respective bodies (MBm, MBn) defining respective reflective surfaces (MSm, MSn) for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with an exposure power of EUV light at a wavelength lying in a range of less than 50 nm being reflected from said reticle while illuminated by said illumination system;said bodies (MBm, MBn) of said reflective optical elements (Mm, Mn) including a material with a temperature dependent coefficient of thermal expansion which is zero at respective zero cross temperatures (T0m, T0n);a support structure for passively or actively supporting said reflective optical elements (Mm, Mn) wherein the temperature of at least a part of the support structure is at a reference temperature TRef;a heater for heating at least one of the bodies (MBm, MBn) including said material with said zero cross temperatures (T0m, T0n);a temperature control system for controlling the temperature of the at least one heated body(MBm, MBn) to a temperature Tk;without heating the bodies (MBm, MBn) with the heater, the exposure of said reflective surfaces MSm and MSn with the exposure power of the EUV light, being reflected by the illuminated reticle and including a spatial distribution of angular, polarisation and intensity in accordance with an illumination setting, resulting in temperature distributions ΔTn(x,y,z)=(Tn(x,y,z)−TRef), ΔTm(x,y,z)=(Tm(x,y,z)−TRef) of said bodies (MBm, MBn) relative to the reference temperature TRef with respective average and maximum temperatures ΔTnav, ΔTmav and ΔTmax and ΔTmmax; and,at least one zero cross temperatures (T0m, T0n) is higher than the maximum of the highest reference temperature TRef and the respective average or maximum temperature added by the reference temperature (ΔTmav+Tref or ΔTmmax+TRef, ΔTnav+TRef or ΔTnmax+TRef), based on the respective spatial temperature distribution ΔTm(x,y,z), ΔTn(x,y,z), expressed as T0m>max(TRef, ΔTmav+TRef), T0m>max(TRef, ΔTmmax+TRef) or T0n>max(TRef, ΔTnav+TRef), T0n>max(TRef, ΔTnmax+TRef). 17. A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising: at least first and second reflective optical elements (Mm, Mn);said reflective optical elements (Mm, Mn) having respective bodies (MBm, MBn) defining respective reflective surfaces (MSm, MSn) for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with an exposure power of EUV light at a wavelength lying in a range of less than 50 nm being reflected from said reticle while illuminated by said illumination system;said bodies (MBm, MBn) including a material having a temperature dependent coefficient of thermal expansion which is zero at at least two zero cross temperatures T10mn and T20mn;a support structure for passively or actively supporting said reflective optical elements (Mm, Mn) wherein the temperature of at least a part of the support structure is at a reference temperature TRef;at least two tempering devices, preferably heaters, for independently heating and/or cooling said at least two bodies (MBn, MBm);a temperature control system for independently controlling the temperature of the at least two heated or cooled bodies (MBn, MBm) to respective temperatures Tkn and Tkm; and,during exposure of the lens with the exposure power of the EUV light, the temperatures Tkn of the temperature controlled body MBn is within an interval of ±5K, better ±2K centered around the first zero cross temperatures T10mn, and the temperatures Tkm of the temperature controlled body MBm is within an interval of ±5K, better ±2K centered around the second zero cross temperatures T20mn. 18. A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising: a plurality of reflective optical elements Mi;said reflective optical elements Mi having respective bodies MBi defining respective reflective surfaces MSi for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with an exposure power of EUV light at a wavelength lying in a wavelength range of less than 50 nm, the EUV light being reflected from said reticle when illuminated by said illumination system;a support structure for passively or actively supporting said reflective optical elements Mi, wherein the temperature of at least a part of the support structure is at a reference temperature TRef;a heater for heating at least one optical element Mk on which a spatial temperature distribution ΔT(x,y,z)=(T(x,y,z)−TRef) relative to the reference temperature TRef is formed out when the projection lens is exposed with the exposure power without heating the heater, the temperature distribution ΔT(x,y,z) having an average temperature ΔTav and a maximum temperature ΔTmax; and,a temperature control system for controlling the temperature of said at least one reflective optical element Mk to a temperature Tk, wherein the body MBk of said at least one heated reflective optical element Mk includes a material with a temperature dependent coefficient of thermal expansion which is zero at a temperature at a temperature higher than the reference temperature TRef; and,before the exposure with the exposure power, the optical element Mk having a temperature Tk by heating it with the heater, the temperature Tk being selected from the group consisting of Tk=T0k−ΔTav; Tk=2*T0k−TRef−ΔTav; Tk=TRef+3*(T0k−TRef)/2−ΔTav; Tk=T0k−ΔTmax; Tk=2*T0k−TRef−ΔTmax; Tk=TRef+3*(T0k−TRef)/2−ΔTmax. 19. A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising: a plurality of reflective optical elements Mi;said reflective optical elements Mi having respective bodies MBi defining respective reflective surfaces MSi for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with an exposure power of EUV light at a wavelength lying in a wavelength range of less than 50 nm, the EUV light being reflected from said reticle when illuminated by said illumination system;a support unit for passively or actively supporting at least one optical element Mk;said support unit including a temperature sensitive element selected from the group consisting of linking points, bipod structures, linking elements, support element and housing structure;the temperature sensitive element being controlled to a constant or to a predefined temperature;a first tempering element for heating and/or cooling the at least one optical element Mk to a temperature Tk;a second tempering element for tempering the temperature sensitive element to the predefined temperature; and,said second tempering element being spatially arranged between the temperature sensitive element and the first tempering element. 20. A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising: a plurality of reflective optical elements Mi;said reflective optical elements Mi having respective bodies MB; defining respective reflective surfaces MSi for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with an exposure power of EUV light at a wavelength lying in a wavelength range of less than 50 nm, the EUV light being reflected from said reticle when illuminated by said illumination system;a support unit for passively or actively supporting at least one optical element Mk;a pressure control system for the control of the pressure Δp within a surrounding of said at least one reflective optical element Mk;said control being based on a parameter selected from the group consisting of the temperature of the optical element Mk, the time, a parameter which directly or indirectly influence the temperature of the optical element Mk, an illumination setting, a change of the reticle, thermally or mechanically induced optical aberration data of the optical element Mk or the projection lens and an output parameter from a model; and,said model input including data selected from the group consisting of the temperature of the reflective optical element Mk, the time, a parameter which directly or indirectly influences the temperature of the optical element Mk, an illumination setting, thermally or mechanically induced optical aberration data of the optical element Mk or the projection lens and a change of the reticle. 21. A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising: a plurality of reflective optical elements Mi;said reflective optical elements Mi having respective bodies MBi defining respective reflective surfaces MSi for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with an exposure power of EUV light at a wavelength lying in a wavelength range of less than 50 nm, the EUV light being reflected from said reticle when illuminated by said illumination system;at least one reflective optical element Mk including a material having a temperature dependent coefficient of thermal expansion which is zero at a zero cross temperature T0k;the body MBk of the optical element Mk being semitransparent to an IR radiation;said at least one reflective optical element Mk with its body MBk including a coating C on or on almost its entire surface of the body MBk; and,the coating C reflecting IR radiation inside said body MBk. 22. A mirror comprising: a body MBk having a reflective surface MSk;a material with a temperature dependent coefficient of thermal expansion which is zero at a zero cross temperature T0k;said body MBk is at least partly coated with a resistive coating C2, wherein the resistive coating C2 has an electrical resistance suitable to heat the body by electrical resistive heating; and,said mirror being adapted for a projection lens of an EUV-lithographic projection exposure system for projecting an object field on a reticle onto an image field on a substrate if the projection lens is exposed with an exposure power of EUV light with a wavelength in a wavelength range of less than 50 nm.
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