Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Optimization of Mg:Ag Cathodes and Effect of LiF Electron Injection Layer on the Characteristics of Top Emission Organic Light Emitting Diodes

전면 유기발광 다이오드 제작시 Mg:Ag 캐소드 최적화 및 LiF 전자주입층 유무에 따른 소자 특성에 관한 연구

  • Song, Min Seok (Department of Electronic Engineering, Gachon University) ;
  • Kwon, Sang Jik (Department of Electronic Engineering, Gachon University) ;
  • Cho, Eou-Sik (Department of Electronic Engineering, Gachon University)
  • 송민석 (가천대학교 전자공학과) ;
  • 권상직 (가천대학교 전자공학과) ;
  • 조의식 (가천대학교 전자공학과)
  • Received : 2022.02.23
  • Accepted : 2022.03.25
  • Published : 2022.03.31
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Abstract

For the process simplification in the fabrication of organic light emitting diode(OLED), top emission OLED (TEOLED) was fabricated without lithium fluoride(LiF) used as an electron injection layer (EIL). After co-deposition of Mg and Ag with a different process conditions, a cathode material adjacent to EIL was optimized when Mg and Ag have a ratio of 1:9 considering sheet resistance and transmittance. From the energy band diagram of TEOLED, band gap difference between Trisaluminium (Alq3) and Mg:Ag cathode show the difference of 0.4 eV according to the usage of LiF The fabricated TEOLED without LiF showed the improvement of 5.2 % and 2.7 % in the luminance and the current density comparing that with LiF. The results show there is no significant difference in OLED characteristics regardless of LIF layer in the TEOLED structures.

Keywords

Acknowledgement

본 논문은 산업통상자원부 '산업혁신인재성장지원사업'의 재원으로 한국산업기술진흥원(KIAT)의 지원을 받아 수행된 연구임(2020년 차세대 디스플레이 공정·장비·소재 전문인력 양성사업, 과제번호: P0012453). 본 성과는 또한 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임 (No. 2020R1F1A1076505).

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