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Inductively Coupled Plasma Chemical Vapor Deposition System for Thin Film Ppassivation of Top Emitting Organic Light Emitting Diodes

전면발광 유기광소자용 박막 봉지를 위한 유도결합형 화학 기상 증착 장치

  • 김한기 (국립금오공과대학교 신소재시스템공학부)
  • Published : 2006.06.01

Abstract

We report on characteristics of specially designed inductively-coupled-plasma chemical vapor deposition (ICP-CVD) system for top-emitting organic light emitting diodes (TOLEDs). Using high-density plasma on the order of $10^{11}$ electrons/$cm^3$ generated by linear-type antennas connected in parallel and specially designed substrate cooling system, a 100 nm-thick transparent $SiN_{x}$ passivation layer was deposited on thin Mg-Ag cathode layer at substrate temperature below $50\;^{\circ}C$ without a noticeable plasma damage. In addition, substrate-mask chucking system equipped with a mechanical mask aligner enabled us to pattern the $SiN_x$ passivation layer without conventional lithography processes. Even at low substrate temperature, a $SiN_x$ passivation layer prepared by ICP-CVD shows a good moisture resistance and transparency of $5{\times}10^{-3}g/m^2/day$ and 92 %, respectively. This indicates that the ICP-CVD system is a promising methode to substitute conventional plasma enhanced CVD (PECVD) in thin film passivation process.

Keywords

References

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