Journal of Sensor Science and Technology (센서학회지)

The Korean Sensors Society (한국센서학회)
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Effect of Air Exposure on ZnO Thin Film for Electron Transport Layer of Quantum Dot Light-Emitting Diode

ZnO 박막 전자수송층의 공기 노출에 의한 양자점 발광다이오드의 특성 변화

  • Eunyong Seo (Department of Semiconductor Engineering, Gyeongsang National University) ;
  • Kyungjae Lee (Department of Semiconductor Engineering, Gyeongsang National University) ;
  • Jeong Ha Hwang (Department of Energy Science and Technology Centre for Artificial Atoms, Sungkyunkwan University (SKKU)) ;
  • Dong Hyun Kim (Department of Semiconductor Engineering, Gyeongsang National University) ;
  • Jaehoon Lim (Department of Energy Science and Technology Centre for Artificial Atoms, Sungkyunkwan University (SKKU)) ;
  • Donggu Lee (Department of Semiconductor Engineering, Gyeongsang National University)
  • 서은용 (경상국립대학교 반도체공학과) ;
  • 이경재 (경상국립대학교 반도체공학과) ;
  • 황정하 (성균관대학교 에너지공학과) ;
  • 김동현 (경상국립대학교 반도체공학과) ;
  • 임재훈 (성균관대학교 에너지공학과) ;
  • 이동구 (경상국립대학교 반도체공학과)
  • Received : 2023.11.13
  • Accepted : 2023.11.22
  • Published : 2023.11.30
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Abstract

We investigated the electrical characteristics of ZnO nanoparticles (NPs) with air exposure that is a widely used electron transport layer for quantum dot light-emitting diodes (QLEDs). Upon air exposure, we observed changes in the density of states (DOS) of the trap levels of ZnO NPs. In particular, with air exposure, the concentration of deep trap energy levels in ZnO NPs decreased and electron mobility significantly improved. Consequently, the air-exposed ZnO reduced leakage current by approximately one order of magnitude and enhanced the external quantum efficiency at the low driving voltage region of the QLED. In addition, based on the excellent conductivity properties, high-brightness QLEDs could be achieved.

Keywords

Acknowledgement

이 성과는 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(No. 2022R1F1A1062675). 이 연구는 2021년도 산업통상자원부및산업기술기획평가원(KEIT) 연구비 지원에 의한 연구임(20016195). 또한, 본 결과물은 2021년도 교육부의 재원으로 한국연구재단의 지원을 받아 수행된 지자체-대학 협력기반 지역혁신 사업의 결과입니다.

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