Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Study on the Electrode Design for an Advanced Structure of Vertical LED

Via-hole 구조의 n-접합을 갖는 수직형 발광 다이오드 전극 설계에 관한 연구

  • Park, Jun-Beom (Optoelectronics Convergence Research Center, Chonnam National University) ;
  • Park, Hyung-Jo (Optoelectronics Convergence Research Center, Chonnam National University) ;
  • Jeong, Tak (New Light Source Center, Korea Photonics Technology Institute) ;
  • Kang, Sung-Ju (Applied Chemical Engineering, Chonnam National University) ;
  • Ha, Jun-Seok (Optoelectronics Convergence Research Center, Chonnam National University) ;
  • Leem, See-Jong (Department of Energy and Electrical Engineering, Korea Polytechnic University)
  • 박준범 (전남대학교 광전자융합기술연구소) ;
  • 박형조 (전남대학교 광전자융합기술연구소) ;
  • 정탁 (한국광기술원 반도체광원연구센터) ;
  • 강성주 (전남대학교 응용화학공학부) ;
  • 하준석 (전남대학교 광전자융합기술연구소) ;
  • 임시종 (한국산업기술대학교 에너지.전기공학과)
  • Received : 2015.12.14
  • Accepted : 2015.12.23
  • Published : 2015.12.30
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Abstract

Recently, light emitting diodes (LEDs) have been studied to improve their efficiencies for the uses in various fields. Particularly in the aspect of chip structure, via hole type vertical LED chip is developed for improvement of light output power, and heat dissipations. However, current vertical type LEDs have still drawback, which is current concentration around the n-contact holes. In this research, to solve this phenomenon, we introduced isolation layer under n-contact electrodes. With this sub-electrode, even though the active area was decreased by about 2.7% compared with conventional via-hole type vertical LED, we could decrease the forward voltage by 0.2 V and wall-plug efficiency was improved approximately 4.2%. This is owing to uniform current flow through the area of n-contact.

최근 Light Emitting Diode (LED)의 효율을 높이기 위한 연구가 활발히 진행 되고 있다. 특히 소자 측면에서는 수평형 LED, 수직형 LED, via-hole 구조의 수직형 LED 등의 다양한 구조가 제시되었다. 본 논문에서는 시뮬레이션을 통해 via-hole 구조의 수직형 LED의 새로운 전극 디자인을 제시하였다. 기존 Via-hole 구조의 수직형 LED의 n-contact hole 주변에 전류가 밀집되는 문제점을 해결하면서 유효 발광면적을 극대화 시켜 소자 전체에 균일한 전류를 주입할 수 있는 소자 디자인에 대해 평가하였다. 시뮬레이션 결과를 바탕으로 최적의 전극 디자인을 실제 디바이스로 제작하여 기존의 via-hole 구조의 수직형 LED와 비교 분석하였다. 최적화된 디자인이 적용된 via hole type 수직형 LED의 경우 기존 디자인에 비해 350 mA 주입시 약 0.2 V의 Forward Voltage 감소하였지만 광 출력은 비슷하여 최종적으로 4.2%의 WPE (Wall plug efficiency)가 향상됨을 보였다.

Keywords

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