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Electrical, Optical and Structural Properties of Indium Zinc Oxide Top Cathode Grown by Box Cathode Sputtering for Top-emitting OLEDs

박스 캐소드 스퍼터로 성장시킨 전면 발광 OLED용 상부 InZnO 캐소드 박막의 전기적, 광학적, 구조적 특성 연구

  • 배정혁 (국립금오공과대학 신소재시스템공학부) ;
  • 문종민 (국립금오공과대학 신소재시스템공학부) ;
  • 김한기 (국립금오공과대학 신소재시스템공학부)
  • Published : 2006.05.01

Abstract

Electrical, optical, and structural properties of indium zinc oxide (IZO) films grown by a box cathode sputtering (BCS) were investigated as a function of oxygen flow ratio. A sheet resistance of $42.6{\Omega}/{\Box}$, average transmittance above 88% in visible range, and root mean spare roughness of $2.7{\AA}$ were obtained even in the IZO layers grown at room temperature. In addition, it is shown that electrical characteristics of the top-emitting organic light emitting diodes (TOLEDs) with the BCS grown-IZO top cathode layer is better than that of TOLEDs with DC sputter grown IZO top cathode, due to absence of plasma damage effect. Furthermore the effects of oxygen flow ratio in IZO films are investigated, based on x-ray photoelectron spectroscopy (XPS), ultra violet/visible (UV/VIS) spectro-meter, scanning electron microscopy (SEM), and atomic force microscopy (AFM) analysis results.

Keywords

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