Journal of the Institute of Electronics Engineers of Korea SD (대한전자공학회논문지SD)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Analysis of Electrical/optical Characteristics Using The Octagonal Finger Type Electrode Pattern for Large-scale Lateral GaN LED

팔각 핑거 타입 전극패턴을 이용한 대면적 수평형 GaN LED의 전기적/광학적 특성 분석

  • Yang, Ji-Won (School of Electrical Engineering, Korea University) ;
  • Kim, Dong-Ho (School of Electrical Engineering, Korea University) ;
  • Kim, Tae-Geun (School of Electrical Engineering, Korea University)
  • 양지원 (고려대학교 전기전자전파공학과) ;
  • 김동호 (고려대학교 전기전자전파공학과) ;
  • 김태근 (고려대학교 전기전자전파공학과)
  • Received : 2010.12.27
  • Accepted : 2011.02.12
  • Published : 2011.03.25
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Abstract

In this paper, we report on the improved electrical and optical characteristics for decreasing current crowding effect and uniform current distribution by designing octagonal finger type electrode pattern in large-scale lateral GaN (Gallium Nitride) LED (Light-emitting diode) with numerical 3-D simulator. Compared with the conventional electrode pattern, proposed electrode pattern was investigated to confirm the improvement of characteristics. From the simulation results of 3-D SpeCLED/RATRO simulator, we found that the forward voltage was decreased by 0.34 V and the light output power was improved by 7.72 mW at the same injection current condition in the LED with proposed octagonal finger type electrode.

본 논문에서는 기존의 대면적 수평형 GaN (Gallium Nitride) LED (Light-emitting diode) 전극패턴이 갖는 전류의 집중현상 및 소자 내 발열문제를 최소화하고 전기적 광학적 특성의 향상을 위하여 팔각 핑거 타입의 전극패턴을 제안하였고, 범용적으로 사용되는 기본 전극패턴 및 그를 대칭적으로 개량한 전극패턴과의 특성을 비교 분석하였다. 상용 3차원 시뮬레이터 SpecLED/RATRO를 통한 시뮬레이션 결과, 본 연구에서 제안한 팔각 핑거 타입의 전극패턴을 갖는 LED 소자가 동일한 350 mA의 전류주입 하에서의 동작전압이 약 0.34 V 정도 감소되는 전기적 특성의 향상을 확인하였고, 광출력 또한 타 구조에 비하여 약 7.72 mW 정도 향상되는 광학적 특성을 확인하였다.

Keywords

References

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