掺镁氧化锌薄膜结构及其光学性质的研究

Structure and Optical Properties of Magnesium-Doped Zinc Oxide Thin Films

以氧化镁(MgO)掺杂的氧化锌(ZnO)陶瓷靶作为溅射靶材,采用射频磁控溅射方法在玻璃衬底上制备了掺镁ZnO(ZnO:Mg)薄膜样品.通过X射线衍射仪和可见-紫外光分光光度计的测试表征,研究了溅射时间对ZnO:Mg薄膜晶体结构和光学性质的影响.结果表明:ZnO:Mg薄膜的结构和性能与溅射时间密切相关.随着溅射时间的增加,ZnO:Mg薄膜(002)晶面的织构系数减小、(110)晶面的织构系数增大,对应的可见光波段的平均透过率降低.溅射时间为15 min时,ZnO:Mg薄膜样品具有最佳的(002)择优取向生长特性和最好的透光性能.同时ZnO:Mg薄膜样品的禁带宽度随溅射时间增加而单调增大.与未掺杂ZnO薄膜相比,所有ZnO:Mg薄膜样品的禁带宽度均变宽.

The magnesium-doped zinc oxide（ZnO： Mg） thin films were deposited on glass substrates by radio-frequency magnetron sputtering technique using the ceramic target fabricated by sintering the mixture of ZnO and MgO nanometer powder. The influence of sputtering time on structure and optical properties of the deposited films was investigated by X-ray diffractometer and UV-Visible spectrophotometer. The results show that the grain growth,structure and optical properties of the thin films are closely related to the sputtering time. As the sputtering time increases,the texture coefficient of（002）plane decreases,the texture coefficient of（110） plane increases,and the average transmittance in the visible range decreases. The thin film deposited at the sputtering time of 15 min has the best crystal quality and the highest optical transmittance. Meanwhile,the band gaps of the deposited films are observed to increase monotonically when the sputtering time increases. Compared with the band gap of undoped ZnO thin film,the direct band gaps of all the deposited thin films are broadened.