Translated Title
Spectroscopic ellipsometry study of the Zn3N2 films prepared by radio-frequency sputtering
Translated Abstract
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 coe?cient) of the films are obtained at a wavelength of 430—850 nm. The optical band gap is calculated from the extinction coe?cient by using the Tauc formula, and a direct band gap of 1.73—1.79 eV is obtained.
Translated Keyword
optical constants
spectroscopic ellipsometry
XRD
Zinc nitride thin film
Access Number
WF:perioarticalwlxb201413051
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