Optical element and projection exposure apparatus based on use of the optical element

Abstract

An optical element for use in an exposure apparatus configured to illuminate a mask with an exposure light beam for transferring a pattern on the mask onto a substrate through a projection optical system and to interpose a given liquid in a space between a surface of the substrate and the projection optical system. The optical element includes a first anti-dissolution member provided directly on a surface of a transmissive optical element on the substrate's side of the projection optical system, and a second anti-dissolution member formed on the first anti-dissolution member on the substrate's side of the first anti-dissolution member.

What is claimed is: 
     
         1 . An optical element to be used for an exposure apparatus configured to illuminate a mask with an exposure light beam for transferring a pattern on the mask onto a substrate through a projection optical system and to interpose a given liquid in a space between a surface of the substrate and the projection optical system, the optical element comprising:
 a first anti-dissolution member provided directly on a surface of a transmissive optical element on the substrate's side of the projection optical system; and   a second anti-dissolution member formed on the first anti-dissolution member on the substrate's side of the first anti-dissolution member.   
     
     
         2 . The optical element according to  claim 1 , wherein each of the first anti-dissolution member and the second anti-dissolution member comprises a film formed by use of an identical material. 
     
     
         3 . The optical element according to  claim 2 , wherein the identical material is SiO 2 . 
     
     
         4 . The optical element according to  claim 1 , wherein the first anti-dissolution member comprises a low contact angle anti-dissolution film. 
     
     
         5 . The optical element according to  claim 1 , wherein the second anti-dissolution member comprises a metal oxide anti-dissolution film having a protective function to protect the optical element against the liquid. 
     
     
         6 . An exposure apparatus configured to illuminate a mask with an exposure light beam for transferring a pattern on the mask onto a substrate through a projection optical system and to interpose a given liquid in a space between a surface of the substrate and the projection optical system, the exposure apparatus comprising:
 a first anti-dissolution member provided directly on a surface of a transmissive optical element on the substrate's side of the projection optical system; and   a second anti-dissolution member formed on the first anti-dissolution member on the substrate's side of the first anti-dissolution member.   
     
     
         7 . The exposure apparatus according to  claim 6 , wherein each of the first anti-dissolution member and the second anti-dissolution member comprises a film formed by use of an identical material. 
     
     
         8 . The exposure apparatus according to  claim 6 , wherein the second anti-dissolution member comprises a metal oxide anti-dissolution film having a protective function to protect the optical element against the liquid. 
     
     
         9 . An optical element to be used for a lithographic projection apparatus configured to illuminate a patterning device with radiation for transferring a pattern on the patterning device onto a substrate through a projection system and to provide an immersion liquid in a space between the substrate and the optical element, the optical element comprising:
 a first layer part to prevent dissolution of the optical element by the immersion liquid, the first layer part provided directly on a surface of a final optical element on the substrate's side of the projection system; and   a second layer part to prevent dissolution of the optical element by the immersion liquid, the second layer part formed on the first layer part on the substrate's side of the first layer part.   
     
     
         10 . The optical element according to  claim 9 , wherein each of the first layer part and the second layer part comprises an identical material. 
     
     
         11 . The optical element according to  claim 10 , wherein the identical material is SiO 2 . 
     
     
         12 . The optical element according to  claim 9 , wherein the first layer part and the second layer part are substantially insoluble in the immersion liquid. 
     
     
         13 . The optical element according to  claim 9 , wherein the first layer part and the second layer part comprise a protective coating which is substantially insoluble in the immersion liquid. 
     
     
         14 . The optical element according to  claim 9 , wherein the first layer part has a low contact angle with the immersion liquid. 
     
     
         15 . The optical element according to  claim 9 , wherein the second layer part comprises a metal oxide. 
     
     
         16 . A lithographic projection apparatus configured to illuminate a patterning device with radiation to transfer a pattern on the patterning device onto a substrate through a projection system and to provide an immersion liquid in a space between the substrate and a final optical element of the projection system, the lithographic apparatus comprising:
 a first layer part to prevent dissolution by the immersion liquid, the first layer part provided directly on a surface of an optical element on the substrate's side of the projection system; and   a second layer part to prevent dissolution by the immersion liquid, the second layer part formed on the first layer part on the substrate's side of the first layer part.   
     
     
         17 . The apparatus according to  claim 16 , wherein each of the first layer part and the second layer part comprises an identical material. 
     
     
         18 . An optical element to be used for a lithographic projection apparatus configured to illuminate a patterning device with radiation for transferring a pattern on the patterning device onto a substrate through a projection system and to provide an immersion liquid in a space between the substrate and the optical element, the optical element comprising:
 a first protective layer part which is substantially insoluble in the immersion liquid, the first protective layer part provided directly on a surface of a final optical element on the substrate's side of the projection system; and   a second protective layer part which is substantially insoluble in the immersion liquid, the second protective layer part formed on the first protective layer part on the substrate's side of the first protective layer part.   
     
     
         19 . The optical element according to  claim 18 , wherein the first protective layer part and the second protective layer part comprise a coating. 
     
     
         20 . A lithographic projection apparatus configured to illuminate a patterning device with radiation to transfer a pattern on the patterning device onto a substrate through a projection system and to provide an immersion liquid in a space between the substrate and a final optical element of the projection system, the lithographic apparatus comprising:
 a first protective layer part which is substantially insoluble in the immersion liquid, the first protective layer part provided directly on a surface of the final optical element on the substrate's side of the projection system; and   a second protective layer part which is substantially insoluble in the immersion liquid, the second protective layer part formed on the first protective layer part on the substrate's side of the first protective layer part.   
     
     
         21 . The apparatus according to  claim 20 , wherein the first layer part and the second layer part comprise a coating. 
     
     
         22 . A lithographic projection apparatus, comprising:
 a projection system configured to project a pattern from a patterning device onto a substrate; and   a liquid supply system configured to at least partly fill a space between the projection system and the substrate with a liquid,   wherein an element of the projection system through which the pattern is projected has, on a surface configured to be in contact with the liquid, a protective coating which is substantially insoluble in the liquid.   
     
     
         23 . The apparatus according to  claim 22 , wherein the protective coating has a thickness equal to or greater than 5 nm. 
     
     
         24 . The apparatus according to  claim 22 , wherein the protective coating has a thickness less than or equal to 200 nm. 
     
     
         25 . The apparatus according to  claim 22 , wherein the protective coating is a metal oxide, SiO 2  or any combination of these materials. 
     
     
         26 . The apparatus according to  claim 22 , wherein the protective coating has two distinct layers. 
     
     
         27 . The apparatus according to  claim 26 , wherein the two distinct layers are of the same material. 
     
     
         28 . A lithographic projection apparatus, comprising:
 a projection system configured to project a pattern from a patterning device onto a substrate; and   a liquid supply system configured to at least partly fill a space between the projection system and the substrate with a liquid,   wherein an element of the projection system through which the pattern is to be projected and configured to be at least in part in contact with the liquid, comprises first and second components of CaF 2 , SiO 2  or a combination of both materials, the components being arranged such that the projected pattern passes through the first component before passing through the second component.   
     
     
         29 . A device manufacturing method comprising projecting a patterned beam of radiation onto a substrate through a liquid provided in a space between an element of a projection system and the substrate, wherein a surface of the element in contact with the liquid comprises a protective coating which is substantially insoluble in the liquid. 
     
     
         30 . A device manufacturing method comprising projecting a patterned beam of radiation onto a substrate through a liquid provided in a space between an element of a projection system and the substrate, wherein the element is at least in part in contact with the liquid and comprises first and second components of CaF 2 , SiO 2  or a combination of both materials, the components being arranged such that the patterned beam of radiation passes through the first component before passing through the second component.