한국광학회지 (Korean Journal of Optics and Photonics)

  • 제18권2호
  • /
  • Pages.155-161
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  • 2007
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  • 1225-6285(pISSN)
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  • 2287-321X(eISSN)
한국광학회 (Optical Society of Korea)
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3차원의 회로 모델링을 이용한 청색 GaN/InGaN LED의 전류 확산 효과에 관한 연구

Study on the Current Spreading Effect of Blue GaN/InGaN LED using 3-Dimensional Circuit Modeling

  • 황성민 (한양대학교 전자컴퓨터공학부, 고속회로연구실) ;
  • 심종인 (한양대학교 전자컴퓨터공학부, 고속회로연구실)
  • Hwang, Sung-Min (Dept. of Electrical and Computer Eng., Hanyang University) ;
  • Shim, Jong-In (Dept. of Electrical and Computer Eng., Hanyang University)
  • 발행 : 2007.04.25
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⟨ 이전 논문 다음 논문 ⟩

초록

본 논문에서는 GaN/InGaN 다중양자우물(MQW)의 청색 발광 다이오드(LED)에서의 3차원적인 전류 및 2차원적인 광 분포를 보여 주기 위해 새롭고 간단한 3차원 회로 모델링과 해석이 처음으로 제안되었으며 이를 실험적으로 검증하였다. LED의 회로 파라미터들은 금속 및 에피 박막의 저항과 다이오드만으로 이루어져 있으며 각각의 파라미터는 전송선 모델(TLM) 및 전압-전류의 특성으로부터 얻을 수 있다. 제안된 방법과 회로 파라미터를 상부로 발광하는(top-surface emitting) LED에 적용하여 금속 및 에피 박막의 각 저항 변화에 따라 활성층을 지나가는 전류 분포의 효과를 정량적으로 해석하였다. 그리고 제작된 청색 LED 소자의 발광 분포는 p-전극 주위에서 어두운 발광 분포를 보이는 해석 결과와 유사한 경향을 보여주었다.

A new and simple method of 3-dimensional circuit modeling and analysis is proposed and verified experimentally for the first time by determining 3-dimensional current flow and 2-dimensional light distribution in blue InGaN/GaN multi-quantum well (MQW) light emitting diode (LED) devices. Circuit parameters of the LED consist of the resistance of the metallic film and epitaxial layer, and the intrinsic diode which represents the active region emitting the light. The circuit parameters are extracted from the transmission line model (TLM) and current-voltage relation. We applied the >> proposed method and extracted circuit parameters to obtain the light emission pattern in a top-surface emitting-type LED. The current spreading effect is analyzed theoretically and quantitatively with a variation of the resistance of metallic and epitaxial layers. The emitting-light distribution of the fabricated blue LED showed a good agreement with the analyzed result, which shows the dark emission intensity at the corner of the p-electrode.

키워드

참고문헌

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