Cleanup method for optics in immersion lithography

Abstract

A lens cleaning module is provided for a lithography system having an exposure apparatus including an objective lens. The system includes a scanning stage for supporting a wafer beneath the objective lens. A cleaning module coupling with the lithography system is provided for cleaning the objective lens in a non-manual cleaning process.

1 . A lens cleaning module for a lithography system having an exposure apparatus including an objective lens, comprising: 
 a scanning stage for supporting a wafer beneath the objective lens; and    a cleaning module coupling with said lithography system is provided for cleaning the objective lens in a non-manual cleaning process.    
   
   
       2 .- 3 . (canceled)  
   
   
       4 . The lens-cleaning module of  claim 1 , wherein the cleaning module includes a heating/drying module for drying the objective lens.  
   
   
       5 . The lens cleaning module of  claim 1 , wherein said lithography system is an immersion lithography apparatus.  
   
   
       6 . The lens-cleaning module of  claim 1 , wherein said exposure apparatus has a light source which emits light having a wavelength of less than about 250 nm.  
   
   
       7 . (canceled)  
   
   
       8 . The lens-cleaning module of  claim 1 , wherein said cleaning module comprises a fluid retaining wall carried by said scanning stage and a cleaning fluid provided on said scanning stage and retained by said fluid retaining wall for contacting the objective lens.  
   
   
       9 . The lens-cleaning module of  claim 1 , wherein said cleaning fluid is ethanol.  
   
   
       10 . (canceled)  
   
   
       11 . The lens-cleaning module of  claim 8 , further comprising a contact material for cleaning and cleaning fluid is distributed between contact material and lens during operation.  
   
   
       12 . (canceled)  
   
   
       13 . A method for patterning semiconductor wafers by immersion lithography to improve exposure quality comprising the steps of: 
 loading a semiconductor wafer on a stage of an immersion lithography apparatus;    filling a liquid between said wafer and an objective lens of said immersion lithography apparatus;    exposing said semiconductor wafer to a light source having a wavelength of less than about 250 nm;    unloading said semiconductor wafer;    cleaning a surface of said objective lens after said exposure step utilizing a non-manual lens cleaning module.    
   
   
       14 .- 15 . (canceled)  
   
   
       16 . The method for patterning semiconductor wafer by immersion lithography according to  claim 13 , wherein said non-manual lens cleaning module further comprising a contact material for cleaning and cleaning fluid is distributed between contact material and lens during cleaning operation.  
   
   
       17 . A method for patterning semiconductor wafers by immersion lithography to improve exposure quality comprising the steps of: 
 utilizing a non-manual lens cleaning module to clean the surface of objective lens before water exposure processing;    loading a semiconductor wafer on a stage of an immersion lithography apparatus;    filling a liquid between said wafer and an objective lens of said immersion lithography apparatus;    exposing said semiconductor wafer to a light source having a wavelength of less than about 250 nm.    
   
   
       18 .- 19 . (canceled)  
   
   
       20 . The method for patterning semiconductor wafer by immersion lithography according to  claim 17 , wherein said non-manual lens cleaning module further comprising a contact material for cleaning and cleaning fluid is distributed between contact material and lens during cleaning operation.