Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Structural and Electrical Characteristics of IZO Thin Films Deposited at Different Substrate Temperature and Hydrogen Flow Rate

증착 온도 및 수소 유량에 따른 IZO 박막의 구조적 및 전기적 특성

  • Han, Seong-Ho (Department of Materials Engineering, Korea University of Technology and Education) ;
  • Lee, Kyu Mann (Department of Materials Engineering, Korea University of Technology and Education)
  • 한성호 (한국기술교육대학교 신소재공학과) ;
  • 이규만 (한국기술교육대학교 신소재공학과)
  • Received : 2013.05.23
  • Accepted : 2013.06.17
  • Published : 2013.06.30
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Abstract

In this study, we have investigated the effect of the substrate temperature and hydrogen flow rate on the characteristics of IZO thin films for the organic light emitting diodes (OLED) devices. For this purpose, IZO thin films were deposited by RF magnetron sputtering at room temperature and $300^{\circ}C$ with various $H_2$ flow rate. In order to investigate the influences of the oxygen, the flow rate of hydrogen in argon mixing gas has been changed from 0.1sccm to 0.9sccm. IZO thin films deposited at room temperature show amorphous structure, whereas IZO thin films deposited at $300^{\circ}C$ show crystalline structure having an (222) preferential orientation regardless of $H_2$ flow rate. The electrical resistivity of IZO film decreased with increasing flow rate of $H_2$ under Ar+$H_2$. The change of electrical resistivity with increasing flow rate of $H_2$ was mainly interpreted in terms of the charge carrier concentration rather than the charge carrier mobility. The electrical resistivity of the amorphous-IZO films deposited at R.T. was lower than that of the crystalline-IZO thin films deposited at $300^{\circ}C$. The increase of electrical resistivity with increasing substrate temperature was interpreted in terms of the decrease of the charge carrier mobility and the charge carrier concentration. All the films showed the average transmittance over 83% in the visible range.

Keywords

References

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