Journal of the Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회논문지)

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
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Electrical and Optical Properties of Semitransparent Metal Electrodes for Top-emission Organic Light-emitting Diodes

전면 발광 유기 발광 소자용 반투명 금속의 전기적 및 광학적 특성

  • 신은철 (홍익대학교 정보디스플레이공학과) ;
  • 안희철 (홍익대학교 정보디스플레이공학과) ;
  • 김태완 (홍익대학교 정보디스플레이공학과)
  • Published : 2008.10.01
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Abstract

Electrical and optical properties of semitransparent Ag and Al layer were studied, which are used for the electrodes in top-emission organic light-emitting diodes. Sheet resistance and transmittance of visible light through a thin layer were measured and analyzed. Several thin metal layers of Ag and Al were deposited onto a glass substrate up to a thickness of 50 nm using a thermal evaporation. Sheet resistance measurements show that a layer thickness is needed more than 15 nm and 20 nm for Ag and Al, respectively, when a proper sheet resistance is assumed to be less than $50{\Omega}/sq$. From the measurements of transmittance of visible light through a thin-metal layer, metallic behavior was observed when the layer thickness is over 25 nm for both films. Thus, from a study of sheet resistance and transmittance of visible light, a minimum proper thickness of semitransparent metal layer is 20 nm and 25 nm for Ag and Al, respectively.

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References

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