System and method for custom-polarized photolithography illumination

Abstract

In one embodiment, a system for custom-polarized photolithography illumination includes an illuminator operable to generate an illumination pattern of light, a polarizer unit operable to variably polarize the light, and a mask pattern defining photolithographic pattern features in two dimensions. The mask pattern is associated with a mask capable of transmitting at least a portion of the variably polarized light through the mask pattern.

1 - 20 . (canceled)  
   
   
       21 . A method for patterning photoresist on a semiconductor wafer, comprising: 
 forming a photoresist layer on a semiconductor wafer;    generating an illumination pattern comprising a quadrupole illumination pattern having a first and second set of symmetrically opposed light beams, the method further comprising rotating the polarization of at least a portion of the illumination pattern such that the first set of symmetrically opposed light beams have polarizations in the same direction and the second set of symmetrically opposed light beams have polarizations in the same direction, wherein the polarization direction of the first set of light beams is perpendicular to the polarization direction of the second set of light beams; and    transmitting the illumination through a mask pattern associated with a mask unto said photoresist layer to define a photolithographic pattern in said photoresist.    
   
   
       22 . The method of  claim 21  further comprising varying the polarization of a different portion of the light using a different polarization rotator.  
   
   
       23 . The method of  claim 21  wherein at least one polarization rotator comprises a half-wave plate.  
   
   
       24 . The method of  claim 21  wherein the illumination pattern comprises a dipole illumination pattern having two symmetrically opposed light beams, the method further comprising rotating the polarization of at least a portion of the illumination pattern such that the two symmetrically opposed light beams have polarizations in the same direction.  
   
   
       25 . The method of  claim 21  further comprising developing said photoresist and processing said semiconductor wafer.