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Characteristics of Amorphous IZO Anode Films Grown on Passivated PES Substrates in Oxygen Free Ambient for Flexible OLEDs

아르곤 가스만을 이용하여 PES 기판 상에 성장시킨 플렉시블 유기발광소자용 비정질 IZO 애노드 박막의 특성

  • 배정혁 (국립금오공과대학교 신소재시스템공학부) ;
  • 문종민 (국립금오공과대학교 신소재시스템공학부) ;
  • 정순욱 (국립금오공과대학교 신소재시스템공학부) ;
  • 강재욱 (서울대학교 OLED 센터) ;
  • 김한기 (국립금오공과대학교 신소재시스템공학부)
  • Published : 2006.12.01

Abstract

Electrical, optical, and structural properties of indium zinc oxide (IZO) anode films grown by a RF magnetron sputtering were investigated as functions of RF power and working pressure in pure Ar ambient. To investigate electrical, optical and structural properties of IZO anode films, 4-point probe and UV/VIS spectrometry, and X-ray diffraction (XRD) were performed, respectively. A sheet resistance of $15.2{\Omega}/{\square}$, average transmittance above 80 % in visible range, expecially above 85 % in 550 nm, and root mean square roughness of 1.13 nm were obtained from optimized IZO anode films grown in oxygen free ambient. All samples show amorphous structure regardless of RF power and working pressure due to low substrate temperature. In addition, XPS depth profile obtained from IZO/PES exhibits that there is no obvious evidence of interfacial reaction between IZO and PES substrate. Furthermore, current-voltage-luminance of the flexible phosphorescent flexible OLEDs fabricated on IZO anode shows dependence on sheet resistance of the IZO anode. These results indicate that the IZO anode is a promising candidate to substitute conventional ITO anode for high-quality flexible displays.

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