NH_3-Ar气氛下制备的Zn_3N_2薄膜的结构和光学性能(英文)

Zn3N2是一种宽带隙半导体材料,在温度高于400°C氧化可生成p型ZnO:N,p型ZnO:N在电子学和光电子学领域有广泛的应用.在NH3-Ar气氛下,用RF磁控溅射金属Zn靶在玻璃衬底上室温制备了Zn3N2薄膜.用紫外-可见分光光度计、X射线衍射仪、X射线光电子谱分析仪、荧光分光光度计对Zn3N2薄膜的光学透过、光学吸收、结构、化学键态和光致发光进行了测量,研究了NH3分压对Zn3N2薄膜的结构和光学特性的影响.XRD分析表明Zn3N2薄膜呈现多晶结构,具有(321)择优取向,Zn3N2(321)衍射峰强度随NH3分压增加而增强.在NH3分压5%～10%制备的Zn3N2薄膜有较低透过率,透过率随NH3分压增加而提高.Zn3N2薄膜是间接带隙半导体,当NH3分压从5%变化到25%时,光学带隙从2.33eV升高到2.70eV.XPS分析表明Zn3N2薄膜在潮湿空气中容易水解.室温下Zn3N2薄膜在437nm和459nm波长出现了发光峰.

Structural and Optical Properties of Zn3N2 Films Prepared by Magnetron Sputtering in NH3-Ar Mixture Gases

The Zn3N2 is a kind of wide band gap semiconductor and it can be converted into p type ZnO:N after oxidation at temperatures higher than 400°C which has significant potential for electronic and optoelectronic applications. The Zn3N2 films were prepared by RF magnetron sputtering a metallic zinc target in NH3 Ar mixture gases on glass substrate at room temperature. The optical transmission, optical absorption, structural property, chemical bonding states, photoluminescence were measured using a double beam spectrophotometer, X ray diffractometer (XRD), X ray Photoelectron Spectroscopy (XPS), fluorescence spectrometer. The effects of NH3 ratio on the structural and optical properties of the films were examined. XRD analysis indicates that the films are polycrystalline and have a preferred orientation of (321). The intensity of the Zn3N2 (321) peak increases with the NH3 ratio. The films prepared with the NH3 ratios of 5%~10% have low transmission values, the transparency of the films get better with the increase of the NH3 ratio. The Zn3N2 films have an indirect band gap, the optical band gap increases from 2.33 to 2.70 eV when the NH3 ratio varies from 5% to 25%. XPS analysis shows that the Zn3N2 film is easily hydrolyzed by air moisture. Photoluminescence spectrum shows two emission peaks, which are located at 437 nm and 459 nm.