摘要
A series of （103）-oriented aluminum-doped zinc oxide （AZO） films were deposited on glass substrates via direct- current pulse magnetron reactive sputtering at different O2-to-Ar gas flow ratios （GFRs）. The optical properties of the films were characterized using the fitted optical constants in the general oscillator model （which contains two Psemi-Tri oscillators） through the use of measured ellipsometric parameters. The refractive index dispersion data below the interband absorption edge were analyzed using a single-oscillator model. The fitted optical energy gap obtained using the single- oscillator model clearly shows a blue shift, followed by a red shift, as the GFR increases from 0.9/18 to 2.1/18. This shift can be attributed to the change in the free electron concentration of the film, which is closely related to the film stress. In addition, the fitted β value indicates that the AZO film falls under the ionic class. The pbotoluminescence spectrum indicates a photoluminescence mechanism of the direct and wide energy gap semiconductor.
A series of （103）-oriented aluminum-doped zinc oxide （AZO） films were deposited on glass substrates via direct- current pulse magnetron reactive sputtering at different O2-to-Ar gas flow ratios （GFRs）. The optical properties of the films were characterized using the fitted optical constants in the general oscillator model （which contains two Psemi-Tri oscillators） through the use of measured ellipsometric parameters. The refractive index dispersion data below the interband absorption edge were analyzed using a single-oscillator model. The fitted optical energy gap obtained using the single- oscillator model clearly shows a blue shift, followed by a red shift, as the GFR increases from 0.9/18 to 2.1/18. This shift can be attributed to the change in the free electron concentration of the film, which is closely related to the film stress. In addition, the fitted β value indicates that the AZO film falls under the ionic class. The pbotoluminescence spectrum indicates a photoluminescence mechanism of the direct and wide energy gap semiconductor.
基金
Project supported by the National Natural Science Foundation of China(Grant No.60807001)
the Foundation of Young Key Teachers from University of Henan Province,China(Grant No.2011GGJS-008)
the Foundation of Graduate Education Support of Zhengzhou University,China
the Foundation of Graduate Innovation of Zhengzhou University,China(Grant No.12L00104)
