Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Control of ZnO Sputtering Growth by Changing Substrate Bias Voltage

ZnO 스퍼터링에서 기판전압의 변화에 의한 성장 조절

  • Meng, Jun (Department of Electrical and Computer Engineering, Ajou University) ;
  • Choi, Jaewon (Department of Electrical and Computer Engineering, Ajou University) ;
  • Jeon, Wonjin (Department of Electrical and Computer Engineering, Ajou University) ;
  • Jo, Jungyol (Department of Electrical and Computer Engineering, Ajou University)
  • ;
  • 최재원 (아주대학교 정보통신대학 전자공학과) ;
  • 전원진 (아주대학교 정보통신대학 전자공학과) ;
  • 조중열 (아주대학교 정보통신대학 전자공학과)
  • Received : 2017.06.21
  • Accepted : 2017.06.26
  • Published : 2017.06.30
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Abstract

Amorphous Si has been used for data processing circuits in flat panel displays. However, low mobility of the amorphous Si is a limiting factor for the data transmission speed. Metal oxides such as ZnO have been studied to replace the amorphous Si. ZnO is a wide bandgap (3.3 eV) semiconductor with high mobility and good optical transparency. When ZnO is grown by sputtering with $O_2$ as an oxidizer, there can be many ion species arising from $O_2$ decomposition. $O^+$, $O_2{^+}$, and $O^-$ ions are expected to be the most abundant species, and it is not clear which one contributes to the ZnO growth. We applied alternating substrate voltage (0 V and -70 V) during sputtering growth. We studied changes in transistor characteristics induced by the voltage switching. We also compared ZnO grown by dc and rf sputtering. ZnO film was grown at $450^{\circ}C$ substrate temperature. ZnO thin-film transistor grown with these methods showed $7.5cm^2/Vsec$ mobility, $10^6$ on-off ratio, and -2 V threshold voltage.

Keywords

References

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