Modified Illumination by Binary Phase Diffractive Patterns on the Backside of a Photomask

마스크 뒷면에 2 위상 회절 격자를 구현한 변형 조명 방법

  • 이재철 (원광대학교 전기전자 및 정보공학부) ;
  • 오용호 (원광대학교 전기전자 및 정보공학) ;
  • 고춘수 (원광대학교 전기전자 및 정보공학부)
  • Published : 2004.07.01


We propose a method that realizes the modified illumination by implementing a binary phase grating at the backside of a photomask. By modeling the relationship between the shape of a grating on the photomask and the light intensity at the pupil plane, we developed a program named MIDAS that finds the optimum grating pattern with a stochastic approach. After applying the program to several examples, we found that the program finds the grating pattern for the modified illumination that we want. By applying the grating at the backside of a photomask, the light efficiency of modified illumination may be improved.


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