Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
권호 표지

Fabrication of Scattering Layer for Light Extraction Efficiency of OLEDs

RIE 공정을 이용한 유기발광다이오드의 광 산란층 제작

  • Bae, Eun Jeong (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University) ;
  • Jang, Eun Bi (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University) ;
  • Choi, Geun Su (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University) ;
  • Seo, Ga Eun (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University) ;
  • Jang, Seung Mi (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University) ;
  • Park, Young Wook (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University)
  • 배은정 (선문대학교 디스플레이반도체공학과 나노 유기전자 연구실) ;
  • 장은비 (선문대학교 디스플레이반도체공학과 나노 유기전자 연구실) ;
  • 최근수 (선문대학교 디스플레이반도체공학과 나노 유기전자 연구실) ;
  • 서가은 (선문대학교 디스플레이반도체공학과 나노 유기전자 연구실) ;
  • 장승미 (선문대학교 디스플레이반도체공학과 나노 유기전자 연구실) ;
  • 박영욱 (선문대학교 디스플레이반도체공학과 나노 유기전자 연구실)
  • Received : 2022.03.04
  • Accepted : 2022.03.25
  • Published : 2022.03.31
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Abstract

Since the organic light-emitting diodes (OLEDs) have been widely investigated as next-generation displays, it has been successfully commercialized as a flexible and rollable display. However, there is still wide room and demand to improve the device characteristics such as power efficiency and lifetime. To solve this issue, there has been a wide research effort, and among them, the internal and the external light extraction techniques have been attracted in this research field by its fascinating characteristic of material independence. In this study, a micro-nano composite structured external light extraction layer was demonstrated. A reactive ion etching (RIE) process was performed on the surfaces of hexagonally packed hemisphere micro-lens array (MLA) and randomly distributed sphere diffusing films to form micro-nano composite structures. Random nanostructures of different sizes were fabricated by controlling the processing time of the O2 / CHF3 plasma. The fabricated device using a micro-nano composite external light extraction layer showed 1.38X improved external quantum efficiency compared to the reference device. The results prove that the external light extraction efficiency is improved by applying the micro-nano composite structure on conventional MLA fabricated through a simple process.

Keywords

Acknowledgement

이 연구는 2020년도 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원 (No. 2020R1C1C1013567)과 2021년도 교육부의 재원으로 한국연구재단의 지원을 받아 수행된 지자체-대학 협력기반 지역혁신 사업(2021RIS-004, 2021H-01-02-09-003)으로 수행된 결과입니다. 또한 선문대학교 차세대반도체기술센터의 분석지원에 감사드립니다.

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