在不同的衬底温度下，使用反应射频磁控溅射法，在玻璃衬底上制备了氮化锌薄膜样品.用X 射线衍射仪、原子力显微镜和椭偏仪对薄膜的晶体结构、表面形貌、光学性质进行了表征分析.薄膜的晶粒尺寸会随着衬底温度的升高先增大后减小，在200C时薄膜的结晶性最好.用椭偏仪测试样品，建立物理模型计算出氮化锌薄膜在430-850 nm范围内的折射率和消光系数等光学参数.利用Tauc公式计算出氮化锌薄膜的光学带隙在1.73-1.79 eV之间.%Zinc nitride (Zn3N2) thin films were deposited on glass substrates by reactive radio-frequency magnetron sputtering from a pure Zn target in nitrogen-argon ambient. X-ray diffraction analysis indicates that the films just after the deposition are polycrystalline with a preferred orientation of (400). With increasing substrate temperature, the grain size in zinc nitride film increases from 26.5 nm (100 C) to 33.6 nm (200 C), and then decreases to 17.8 nm (300 C). Atomic force microscopy reveals that the film surface morphology is dependent on the substrate temperature. With reflective spectroscopic ellipsometry, the ellipsometric parameters ψ and ∆ of Zn3N2 films are measured. Then, a new model for Zn3N2 films is built. With the Tauc-Lorentz dispersion formula, the ellipsometric data are fitted, and both the thickness and optical constants (refractive index and extinction coefficient) of the films are obtained at a wavelength of 430—850 nm. The optical band gap is calculated from the extinction coefficient by using the Tauc formula, and a direct band gap of 1.73—1.79 eV is obtained.
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