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Design of Structure for High-Efficiency LEDs on Patterned Sapphire Substrate

LED용 사파이어 기판의 고효율 패턴 설계

  • Kang, Ho-Ju (Department of Cogno-Mechatronics Engineering, Pusan National University) ;
  • Song, Hui-Young (Department of Cogno-Mechatronics Engineering, Pusan National University) ;
  • Jeong, Myung-Yung (Department of Cogno-Mechatronics Engineering, Pusan National University)
  • 강호주 (부산대학교 인지메카트로닉스공학과) ;
  • 송희영 (부산대학교 인지메카트로닉스공학과) ;
  • 정명영 (부산대학교 인지메카트로닉스공학과)
  • Received : 2011.03.25
  • Accepted : 2011.12.19
  • Published : 2011.12.30

Abstract

The light extraction efficiency in GaN based LED was analyzed qualitatively. The extraction efficiency was simulated with patterned shape, depth, size and spacing by using ray-tracing simulation. In simulation result, patterned shape and depth for the optimized extraction efficiency in PSS LED were in indented Hemi-sphere solid. Through the optimal patterning of the various factors, about 40% enhancement in extraction efficiency was obtained.

GaN 기반의 LED에서 광 추출 효율을 정량적으로 분석하였다. Ray-Tracing기반의 시뮬레이션을 이용하여 사파이어 기판에 형성된 패턴의 형태, 크기, 깊이, 간격들을 분석하여 최적의 패턴 요소들을 도출하였다. 시뮬레이션의 결과로 최적의 패턴 형태는 반구 형태에서 높은 광 추출 효율을 보였다. 일반적인 패턴이 없는 사파이어 기판을 사용한 LED의 광 추출 효율보다 반구 형태의 패턴을 가진 사파이어 기판에서 약 40% 향상된 광 추출 효율을 보였다.

Keywords

References

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