Performance of Organic light-emitting diode by various surface treatments of indium tin oxide

Indium tin oxide 기판의 표면처리에 따른 유기 발광다이오드의 특성

  • 김선혁 (世宗大學校 電子工學科) ;
  • 한정환 (世宗大學校 電子工學科)
  • Published : 2002.09.01

Abstract

We have done various treatments of indium tin oxide (ITO) surface for organic light-emitting diodes (OLEDs), and investigated the surface states by different surface treatments using atomic force microscopy (AFM) and Auger electron spectroscopy (AES). We have fabricated OLEDs deposited by ultra-high vacuum molecular beam deposition system and studied the characteristics of the OLEDs. We have observed the dramatical improvement of the performance of OLEDs fabricated on ITO substrates treated by $O_2$ plasma treatment reduces the carbon comtamination of ITO surfaces and increases the work function of ITO.

유기 발광 다이오드를 위한 indium oxide (ITO) 기판을 여러 가지로 방법으로 표면처리를 하고, 이에 따른 atomic force microscopy (AFM)에 의한 morphology의 변화와 표면에서 변화된 원소들의 조성비를 Auger electron spectroscopy (AES)분석에 의하여 조사하였다. 또한 이 기판을 사용하여 초고진공분자선 증착방법에 의하여 유기 발광다이오드를 제작하고 그 특성을 조사하였다. 그 결과 산소플라즈마으로 표면 처리한 ITO 기판 위에 제조된 organic light-emitting diode (OLED)소자의 특성이 향상되었다. 그것은 AES의 분석에 의하면 ITO 표면의 오염된 탄소가 제거되고 ITO의 일함수가 증가되어 정공이 유기물 층으로 용이하게 주입한 결과로 판단된다.

Keywords

References

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