Dependency of Oxygen Partial Pressure of ITO Films for Electrode of Oxide-based Thin-Film Transistor

산화물기반 박막트랜지스터 전극용 ITO박막의 제작시 투입 산소 분압 의존성

  • 김경환 (가천대학교 IT융합대학 전기공학과)
  • Received : 2021.05.31
  • Accepted : 2021.06.17
  • Published : 2021.06.30

Abstract

In this study, we investigated the oxygen partial pressure effect of ITO films for electrodes of oxide-based Thin-Film Transistor (TFT). Firstly, we deposited single ITO films on the glass substrate at room temperature. ITO films were prepared at the various partial pressures of oxygen gas 0-7.4% (O2/(Ar+O2)). As increasing oxygen on the process of film deposition, electrical properties were improved and optical transmittance increased in the visible light range (300-800 nm). For the electrode of TFT, we fabricated a TFT device (W/L=1000/200 ㎛) with ITO films as the source and drain electrode on the silicon wafer. Except for the TFT device combined with ITO film prepared at the oxygen partial pressure ratio of 7.4%, We confirmed that TFT devices with ITO films via FTS system operated as a driving device at threshold voltage (Vth) of 4V.

Keywords

Acknowledgement

이 논문은 2019년도 가천대학교 교내연구비 지원에 의한 결과임(GCU-2019-0302).

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