Liquid immersion lithography system with tilted liquid flow

Abstract

A liquid immersion lithography system including a projection optical system for directing electromagnetic radiation onto a substrate, and a showerhead for delivering liquid flow between the projection optical system and the substrate. The showerhead includes an injection nozzle and a retrieval nozzle located at different heights. The liquid flow is tilted relative to the substrate. A direction from the injection nozzle to the retrieval nozzle is tilted at approximately 1 to 2 degrees relative to the substrate.

1 . A liquid immersion lithography system, comprising: 
 a projection optical system to direct electromagnetic radiation onto a substrate; and    a showerhead to deliver liquid flow between the projection optical system and the substrate,    wherein the showerhead includes an injection nozzle and a retrieval nozzle located at different heights.    
   
   
       2 . The liquid immersion lithography system of  claim 1 , wherein the liquid flow is tilted relative to the substrate.  
   
   
       3 . The liquid immersion lithography system of  claim 1 , wherein a direction from the injection nozzle to the retrieval nozzle is tilted at approximately 1 to 2 degrees relative to the substrate.  
   
   
       4 . A liquid immersion lithography system comprising: 
 a projection optical system to expose a substrate; and    an injection nozzle and a retrieval nozzle to deliver tilted liquid flow between the projection optical system and the substrate.    
   
   
       5 . The liquid immersion lithography system of  claim 4 , wherein the tilted liquid flow is tilted at approximately  1  to  2  degrees relative to the substrate.  
   
   
       6 . An exposure system comprising: 
 in order of light propagation, an illumination source, a condenser lens, a contrast device and projection optics;    a liquid delivery system to provide liquid to an exposure area below the projection optics; and    means for providing tilted liquid flow of the liquid.    
   
   
       7 . An exposure system comprising: 
 in order of light propagation, an illumination source, a condenser lens, a contrast device and projection optics;    a liquid delivery system to provide liquid to an exposure area of a substrate; and    means for tilting the substrate relative to a horizontal.    
   
   
       8 . The system of  claim 6 , wherein the means for tilting also tilts the projection optics.