Light Enhancement Al2O3 Passivation in InGaN/GaN based Blue Light-emitting Diode Lamps

  • So Soon-Jin (Knowledge*On Inc.) ;
  • Kim Kyeong-Min (School of Electrical Electronic and Information Engineering, Wonkwang University) ;
  • Park Choon-Bae (School of Electrical Electronic and Information Engineering, Wonkwang University)
  • Published : 2006.08.01


In this study, sputtered $Al_2O_3$ thin films were evaluated as a passivation layer in the process of InGaN-based blue LEDs in order to improve the brightness of LED lamps. In terms of packaged LED lamps, lamps with $Al_2O_3$ passivation layer emanated higher brightness than those with $SiO_2$ passivation layer, and LED lamps with 90 nm $Al_2O_3$ passivation layer were the brightest among four kinds of lamps. Although lamps with $Al_2O_3$ passivation had a slight increase in operating voltage, their brightness was improved about 13.6 % compare to the lamps made of conventional LEDs without the changes of emitting wavelength.


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