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Enhanced Luminous Intensity in LEDs with Current Blocking Layer

전류 차단 층을 갖는 LED의 향상된 광세기

  • 윤석범 (공주대학교 광공학과) ;
  • 권기영 (공주대학교 전기전자제어공학부) ;
  • 최기석 (공주대학교 전기전자공학과)
  • Received : 2014.06.02
  • Accepted : 2014.07.20
  • Published : 2014.07.28

Abstract

Inserting a $SiO_2$ layer underneath the p-pad electrode as the current blocking layer (CBL) structure and extending p-metal finger patterns, the GaN LEDs using an indium-tin-oxide (ITO) layer show the improved light output intensity, resulting from better current spreading and reduced light loss on the surface of p-pad metal. The LEDs with an oxide layer of $100{\mu}m$-pad-width and $6{\mu}m$-finger-width have better light output intensities than those with an oxide layer of $105{\mu}m$-pad-width and $12{\mu}m$-finger-width. Using the ATLAS device simulator from Silvaco Corporation, the current density distributions on the active layer in CBL LEDs have been investigated.

Keywords

GaN LED;Current Blocking Layer;$SiO_2$ Layer;Current Spreading;Simulation

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