White Electroluminescent Device by ZnS: Mn, Cu, Cl Phosphors

  • Kim, Jong-Su (Division of Image Information Science and Engineering, Pukyong National University) ;
  • Park, Je-Hong (Division of Image Information Science and Engineering, Pukyong National University) ;
  • Lee, Sung-Hun (Division of Image Information Science and Engineering, Pukyong National University) ;
  • Kim, Gwang-Chul (School of Liberal Arts, Korea University of Technology and Education) ;
  • Kwon, Ae-Kyung (Institute of Physics and Applied Physics, Yonsei University) ;
  • Park, Hong-Lee (Institute of Physics and Applied Physics, Yonsei University)
  • 김종수 (부경대학교 이미지시스템공학과) ;
  • 박재홍 (부경대학교 이미지시스템공학과) ;
  • 이성훈 (부경대학교 이미지시스템공학과) ;
  • 김광철 (한국기술교육대학교 교양학부) ;
  • 권애경 (연세대학교 물리학과) ;
  • 박홍이 (연세대학교 물리학과)
  • Published : 2006.09.30

Abstract

White-light-emitting ZnS:Mn, Cu, Cl phosphors with spherical shape and the size of $20\;{\mu}m$ are successfully synthesized. They have the double phases of cubic and hexagonal structures. They are applied to electroluminescent (EL) devices by silk screen method with the following structure: $electrode/BaTiO_3$ insulator layer ($50{\sim}60\;{\mu}m$)/ ZnS:Mn, Cu, Cl phosphor layer ($30{\sim}50\;{\mu}m$)/ITO glass. The EL devices are driven with the voltage of 100 V and the frequency of 400 Hz. The EL devices show the three emission peaks. The blue and green emission bands are originated from $CICu^{2+}$ transition and $ClCu^+$ transition, respectively. The yellow emission band results from $^4T^6A$ transition of $Mn^{2+}$ ion. As an increase of Cu concentrations, the blue and green emission intensities decrease whereas the yellow emission intensity increases; the quality becomes warm white. It is due to the energy transfer from the blue and green bands to the yellow band.

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