The Journal of the Korea institute of electronic communication sciences (한국전자통신학회논문지)

Korea Institute of Electronic Communication Science (한국전자통신학회)
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Dependence of Electrical and Optical Properties on Substrate Temperatures of AZO Thin Films

기판온도에 의한 AZO 박막의 전기적 및 광학적 특성 변화

  • 강성준 (전남대학교 전기및반도체공학전공) ;
  • 정양희 (전남대학교 전기및반도체공학전공)
  • Received : 2023.10.17
  • Accepted : 2023.12.27
  • Published : 2023.12.31
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Abstract

We prepared AZO (Al2O3 : 3 wt %) thin films according to the substrate temperature using the pulsed laser deposition method and the structural, electrical, and optical properties of the thin films were investigated. The AZO thin film deposited at 400℃ showed the best (002) orientation and the FWHM was 0.38°. As a result of the investigation of electrical properties, it was confirmed that the carrier concentration and mobility increased and the resistivity decreased as the substrate temperature increased. The average transmittance in the visible light region showed a high value of 85% or more regardless of the substrate temperature. The Burstein-Moss effect, in which the carrier concentration would increase with increasing substrate temperature thereby widening the energy band gap, was also observed. The resistivity and the figure of merit of the AZO thin film deposited at a substrate temperature of 400℃ were 6.77 × 10-4 Ω·cm and 1.02 × 104 Ω-1·cm-1 respectively, showing the best value.

본 연구에서는 본 연구에서는 펄스 레이저 증착법으로 기판온도에 따른 AZO(Al2O3 : 3 wt %)박막을 제작하여, 구조적 특성과 전기적 및 광학적 특성을 조사하였다. 기판온도 400℃ 에서 증착한 AZO박막에서 가장 우수한 (002) 배향성을 나타내었으며, 이때의 반가폭은 0.42° 였다. 전기적 특성을 조사한 결과, 기판온도가 상승함에 따라 캐리어 농도와 이동도는 증가하였고 비저항은 감소하였다. 가시광 영역에서의 평균 투과도는 기판온도에 상관없이 85% 이상의 높은 값을 나타내었고, 기판온도에 상승함에 따라 캐리어 농도가 증가하고 이로 인해 에너지 밴드갭이 넓어지는 Burstein-Moss효과도 관찰할 수 있었다. 기판온도 400℃ 에서 증착한 AZO박막의 비저항과 재료평가지수는 각각 6.77 × 10-4 Ω·cm 과 1.02 × 104 Ω-1·cm-1 로 가장 우수한 값을 나타내었다.

Keywords

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