Ga-doped ZnO 투명전극을 적용한 교류무기전계발광소자 특성 연구

Top-emission Electroluminescent Devices based on Ga-doped ZnO Electrodes

  • 이운호 (부경대학교 과학기술융합전문대학원) ;
  • 장원태 (부경대학교 융합디스플레이공학과) ;
  • 김종수 (부경대학교 융합디스플레이공학과) ;
  • 이상남 (부경대학교 인쇄정보공학과)
  • Lee, Wun Ho (Department of LED Convergence Engineering, Pukyong National University) ;
  • Jang, Won Tae (Department of Display Engineering, Pukyong National University) ;
  • Kim, Jong Su (Department of Display Engineering, Pukyong National University) ;
  • Lee, Sang Nam (Department of Graphic arts and Information Engineering, Pukyong National University)
  • 투고 : 2017.05.18
  • 심사 : 2017.06.19
  • 발행 : 2017.06.30

초록

We explain optical and electrical properties of top and bottom-emission structured alternating-current powder electroluminescent devices (ACPELDs) with Ga-doped ZnO(GZO) transparent electrode. The top-emission ACPELDs were layered as the metal electrode/dielectric layer/emission layer/top transparent electrode and the bottom-emission ACPELDs were structured as the bottom transparent electrode/emission layer/dielectric layer/metal electrode. The yellow-emitting ZnS:Mn, Cu phosphor and the barium titanate dielectric layers were layered through the screen printing method. The GZO transparent electrode was deposited by the sputtering, its sheet resistivity is $275{\Omega}/{\Box}$. The transparency at the yellow EL peak was 98 % for GZO. Regardless of EL structures, EL spectra of ACPELDs were exponentially increased with increasing voltages and they were linearly increased with increasing frequencies. It suggests that the EL mechanism was attributed to the impact ionization by charges injected from the interface between emitting phosphor layer and the transparent electrode. The top-emission structure obtained higher EL intensity than the bottom-structure. In addition, charge densities for sinusoidal applied voltages were measured through Sawyer-Tower method.

키워드

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