Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Characterization of Thin Film Passivation for OLED by PECVD

PECVD에 의한 OLED 소자의 Thin Film Passivation 특성

  • Kim, KwanDo (Department of Nano Engineering, Dong-A University) ;
  • Jang, SeokHee (Department of Nano Engineering, Dong-A University) ;
  • Kim, JongMin (Department of Chemical Engineering, Dong-A University) ;
  • Chang, SangMok (Department of Chemical Engineering, Dong-A University)
  • 김관도 (동아대학교 공과대학 나노공학과) ;
  • 장석희 (동아대학교 공과대학 나노공학과) ;
  • 김종민 (동아대학교 공과대학 화학공학과) ;
  • 장상목 (동아대학교 공과대학 화학공학과)
  • Received : 2011.10.18
  • Accepted : 2012.02.07
  • Published : 2012.06.01
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Abstract

The relatively short lifetime is a major obstruction for the commercial applications of OLED. One of the reason for the short lifetime is that the organic materials are interacted with water or oxygen in the atmosphere. Protection of water or oxygen from diffusing into the organic material layers are necessary to increase the lifetime of OLED. Although encapsulation of OLED with glass or metal cans has been established, passivation methods of OLED by organic/inorganic thin films are still being developed. In this paper we have developed in-situ passivation system and thin film passivation method using PECVD by which deposition can be performed at room temperature. We have analyzed the characteristics of the passivated OLED device also. The WVTR (Water Vapor Transmission Rate) for the inorganic thin film mono-layer can be reached down to $1{\times}10^{-2}g/m^2{\cdot}day$ and improved lifetime can be obtained. Thin film passivation methods are expected to be applied to flexible display.

OLED 소자는 수분과 산소의 침투에 의하여 유기물이 열화되어 수명이 감소하는 문제점을 가지고 있다. 이러한 문제점을 해결하기 위해서 OLED 소자의 봉지 기술이 최근 연구되고 있다. 현재 유리나 금속 용기를 이용하여 캡슐화 하는 방법이 널리 사용되고 있지만 이러한 방법으로는 유연한(flexible) 소자의 구현이 어렵기 때문에 이를 대체할 수 있는 기술들이 연구되고 있다. 박막 필름을 이용한 OLED의 봉지 기술은 유연한 디스플레이에 적용할 수 있는 기술로 사용될 수 있다. 본 연구에서는 치밀하고 결함이 없는 패시베이션(passivation) 박막을 형성하기 위해서 상온에서 증착이 가능한 PECVD를 이용한 무기 박막 증착 방법을 개발하고 증착 조건과 구조에 따른 OLED의 특성 변화를 분석하였다. 하나의 시스템에서 in-situ로 패시베이션할 수 있는 시스템 및 공정을 구축하였으며 단일 무기 박막의 WVTR(Water Vapor Transmission Rate) 값을 $1{\times}10^{-2}g/m^2{\cdot}day$ 이하로 확보하였고 제작된 박막을 패시베이션막으로 유연한 디스플레이에 적용할 수 있는 가능성을 제시하였다.

Keywords

Acknowledgement

Supported by : 한국연구재단

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