Ge/SiO_2和Ge/ZnO/SiO_2薄膜的磁控溅射制备及电学性能

Preparation and electrical properties of Ge/SiO_2 and Ge/ZnO/ SiO_2 films by magnetron sputtering Method

采用射频磁控溅射方法以石英玻璃为衬底分别沉积制备出了Ge/SiO2和Ge/ZnO/SiO2薄膜。X射线衍射表明薄膜展示了明显的ZnO衍射峰和较弱的Ge衍射峰;傅里叶变换红外光谱曲线证明薄膜均具有各自的特征吸收峰;扫描电镜结果显示薄膜为颗粒状团簇结构,并且加入ZnO中间层可以有效的改善Ge层的质量。同时,对所得薄膜材料的电流-电压性能进行了研究,结果发现,Ge/SiO2薄膜的I-V曲线拟合后为斜线,相当于电阻;ZnO/SiO2薄膜为直线,可以认为是绝缘体;Ge/ZnO/SiO2薄膜在-10～10V之间电流电压呈线性关系,其电阻比Ge/SiO2薄膜小,当电压值超过15V之后,电流急剧增加而迅速使薄膜击穿,薄膜导通。

Ge/SiO2 and Ge/ZnO/SiO2 thin films were deposited by radio frequency magnetron sputtering method.X-ray diffraction results indicated that obvious ZnO diffraction peaks and weak Ge diffraction peaks were observed.By FT-IR spectra exhibited the films hadtheir own absorption peaks.SEM images showed that the films were the cluster structure,and ZnO layer improved effectively the quality of Ge layer.In addition,I-V properties of the thin films were studied.The results showed that the I-V curve fitting of Ge/SiO2 and ZnO/SiO2 were a oblique line（resistance） and a straight line（insulator）,respectively.For Ge/ZnO/SiO2 film,resistance value of the I-V curve was lower than that of Ge/SiO2 film when the voltage was in range of-10 ~ 10V.When the voltage was bigger than 15V,the current increased sharply and quickly which made the film breakdown to a conductor.