Effect of the Concentration of Oxygen Vacancies on the Structural and Electrical Characteristics of MZO Thin Films

산소공공 농도에 따른 MZO 투명전도성 박막의 구조적 및 전기적 특성

  • Jong Hyun Lee (Future Convergence Engineering Major, Dept. of Energy, Materials and Chemical Engineering, Korea University of Technology and Education ) ;
  • Kyu Mann Lee (Future Convergence Engineering Major, Dept. of Energy, Materials and Chemical Engineering, Korea University of Technology and Education )
  • 이종현 (한국기술교육대학교 에너지신소재화학공학부 미래융합공학전공) ;
  • 이규만 (한국기술교육대학교 에너지신소재화학공학부 미래융합공학전공)
  • Received : 2023.02.13
  • Accepted : 2023.03.07
  • Published : 2023.03.31

Abstract

We have investigated the effect of the concentration of oxygen vacancies on the characteristics of Mo-doped ZnO (MZO) thin films for the TCO (transparent conducting oxide). For this purpose, MZO thin films were deposited by RF magnetron sputtering at different substrate temperature from room temperature to 300℃. The electrical resistivity of the MZO films decreases with increasing substrate temperature up to 100℃ and then gradually increases at higher temperatures. To investigate the influences of the ambient gases, the flow rate of oxygen and hydrogen in argon was varied from 0.1 sccm to 0.5 sccm. The MZO thin films were preferentially oriented to the (002) direction, regardless of the ambient gases used. The electrical resistivity of the MZO thin films increased with increasing O2 flow rates, whereas the electrical resistivity decreased sharply under an Ar+H2 atmosphere and was nearly the same, regardless of the H2 flow rate used. As the oxygen vacancy concentration increases, the resistivity intended to decrease. In conclusion, Oxygen vacancy affects the MZO thin film's electrical characteristics. All the films showed an average transmittance of over 80% in the visible range.

Keywords

Acknowledgement

본 논문은 교육부의 재원으로 한국연구재단의 BK21 FOUR 사업, 2021학년도 한국기술교육대학교 교수교육연구진흥과제 및 2022년도 교육부의 재원으로 한국연구재단의 지원을 받아 수행된 지자체-대학 협력기반 지역혁신 사업(2021RIS-004)의 결과입니다.

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