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Structural, Electrical, and Optical Properties of AZO Thin Films Subjected to Rapid Thermal Annealing Temperature

급속 열처리 온도 변화에 따른 AZO 박막의 구조, 전기 및 광학적 특성

  • 정재용 (고려대학교 신소재공학과) ;
  • 조신호 (신라대학교 전자재료공학과)
  • Published : 2010.04.01

Abstract

We have investigated the influence of rapid thermal annealing (RTA) temperature on properties of Al-doped zinc oxide (AZO) thin films deposited on glass substrate by using radio-frequency magnetron sputtering. The RTA is performed in a nitrogen ambient in the temperature range from 300 to $600^{\circ}C$ for 1 minute in a rapid thermal annealer after growing the AZO thin films. The crystallographic structure and the surface morphology of AZO thin film are measured by using X-ray diffraction, and atomic force microscopy and scanning electron microscopy, respectively. The optical transmittance of the deposited thin films is examined in the wavelength range of 300-1100 nm, where the average transmittance is above the 90% in the visible and near-infrared regions. The optical bandgap is calculated from the Tauc's model, and it shows a significant dependence on the RTA temperature. As for the electrical properties of the thin films, the AZO thin film annealed at $400^{\circ}C$ shows the lowest electrical resistivity of $8.6{\times}10^{-3}{\Omega}cm$ and the Hall mobility of $11.3cm^2$/V-sec. These results suggest that the RTA temperature is an important parameter to influence on the structural, electrical, and optical properties of AZO thin films.

Keywords

References

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