Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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The Size Effect and Its Optical Simulation of Y3Al5O12:Ce3+ Phosphors for White LED

백색 LED용 Y3Al5O12:Ce3+ 형광체 크기 효과 및 광 시뮬레이션

  • Lee, Sung Hoon (The Phosphor Material Laboratory, Pukyong National University) ;
  • Kang, Tae Wook (Interdisciplinary Program of LED and Solid State Lighting Engineering, Pukyong National University) ;
  • Kim, Jong Su (Interdisciplinary Program of LED and Solid State Lighting Engineering, Pukyong National University)
  • 이성훈 (부경대학교 형광소재은행연구소) ;
  • 강태욱 (부경대학교 LED공학협동과정) ;
  • 김종수 (부경대학교 LED공학협동과정)
  • Received : 2019.01.22
  • Accepted : 2019.03.17
  • Published : 2019.03.31
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Abstract

In this study, we synthesized two $Y_3Al_5O_{12}:Ce^{3+}$ phosphors ($7{\mu}m$-sized and $2{\mu}m$-sized YAG) with different sizes by controlling particles sizes of starting materials of the phosphors for white LED. In the smaller one ($2{\mu}m$-sized YAG), its photoluminescence intensity in the reflective mode was 63 % that of the bigger one ($7{\mu}m$-sized YAG); the quantum efficiencies were 93 % and 70 % for the smaller and the bigger ones. Two kinds of white LED packages with the same color coordinates were fabricated with a blue package (chip size $53{\times}30$) and two phosphors. The luminous flux of the white LED package with the smaller YAG phosphor was 92 % of that with the bigger one, indicating that the quantum efficiency of phosphor dispersed inside LED package was higher than that of the pure powder. It was consistently confirmed by the optical simulation (LightTools 6.3). It is notable according to the optical simulation that the white LED with the smaller phosphor showed 24 % higher luminous efficiency. If the smaller one had the same quantum efficiency as the bigger one (~93 %). Therefore, it can be suggested that the higher luminous efficiency of white LED can be possible by reducing the particle size of the phosphor along with maintaining its similar quantum efficiency.

Keywords

References

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