Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Electrical properties of the Al doped ZnO thin films fabricated by RF magnetron sputtering system with working pressure and oxygen contents

RF magnetron sputtering법으로 제조한 Al doped ZnO 박막의 산소함량과 압력변화에 따른 전기적 특성 변화

  • Kim, Jong-Wook (Electronic Engineering of Cheongju University) ;
  • Kim, Hong-Bae (School of Electronic and Information Engineering, Cheongju University)
  • 김종욱 (청주대학교 전자공학과) ;
  • 김홍배 (청주대학교 전자정보공학부)
  • Received : 2010.11.30
  • Accepted : 2010.12.17
  • Published : 2010.12.31
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Abstract

The AZO thin films were deposited on the corning 1737 glass plate by the RF magnetron sputtering and effects of working pressure and oxygen contents on the electrical properties were investigated. XRD spectra showed a preferred orientation along the c-axis and a minimum FWHM for the 70mTorr. From the surface analysis (AFM), the number of crystal grain of AZO thin film increased as working pressure increased. The film deposited with 70mTorr of working pressure showed n-type semiconductor characteristic having suitable resistivity $-1.59{\times}10^{-2}{\Omega}cm$, carrier concentration $-10.1{\times}10^{19}cm^{-3}$, and mobility $-4.35cm^2V^{-1}s^{-1}$ while other films by 7 mTorr, 20 mTorr of working pressure closed to metallic films. The films including the oxygen represent stoichiometric composition similar to the oxide. The transmittance of the film was over 85% in the visible light range regardless of the changes in working pressure and oxygen contents.

Keywords

References

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