Structural and Electrical Characteristics of IGZO thin Films deposited at Different Substrate Temperature

기판온도에 따른 IGZO 박막의 구조적 및 전기적 특성

  • Lee, Mingyu (Dept. of Materials Engineering, Korea University of Technology and Education) ;
  • Lee, Kyu Mann (Dept. of Materials Engineering, Korea University of Technology and Education)
  • 이민규 (한국기술교육대학교 신소재공학과) ;
  • 이규만 (한국기술교육대학교 신소재공학과)
  • Received : 2016.01.05
  • Accepted : 2016.02.29
  • Published : 2016.03.31

Abstract

In this study, we have investigated the effect of the substrate temperature on the characteristics of IGZO thin films for the TCO(transparent conducting oxide). For this purpose, IGZO thin films were deposited by RF magnetron sputtering at various substrate temperature (room temperature ${\sim}400^{\circ}C$). IGZO thin films deposited at room temperature show amorphous structure, whereas IGZO thin films deposited at $250^{\circ}C$ or more show crystalline structure having an (222) preferential orientation. The electrical resistivity of IGZO film increased with increasing temperature. The change of electrical resistivity with increasing temperature was mainly interpreted in terms of the charge carrier concentration rather than the charge carrier mobility. The electrical resistivity of the amorphous-IGZO films deposited at R.T. was lower than that of the crystalline-IGZO thin films deposited at $300^{\circ}C$. The transmittance of the IGZO films deposited at $300^{\circ}C$ was decreased deposited with hydrogen gas.

Keywords

References

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