磁控共溅射法制备的Zn_2GeO_4多晶薄膜结构及其光致发光研究  

Structure and photoluminescence of Zn_2GeO_4 polycrystalline films prepared by radio-frequency magnetron sputtering

作　　者：王振宁[1] 江美福[1] 宁兆元[1] 朱丽[1] 

机构地区：[1]苏州大学物理科学与技术学院,苏州215006

出　　处：《物理学报》2008年第10期6507-6512,共6页Acta Physica Sinica

摘　　要：用射频磁控共溅射方法在不同温度的单晶硅基片上生长薄膜,然后在800℃真空环境下对薄膜进行退火处理,成功获得了结晶状态良好的Zn2GeO4多晶薄膜.利用X射线衍射(XRD),X射线光电子能谱(XPS)和原子力显微镜(AFM)对薄膜进行了结构、成分和形貌分析,研究了基片温度对三者的影响.结果显示,当基片温度升高到400℃以上时,薄膜中的Zn2GeO4晶粒在(220)方向上显示出了明显的择优取向.当基片温度在500—600℃范围内,有利于GeO2结晶相的形成.XPS显示薄膜中存在着Zn2GeO4,GeO2,GeO,ZnO四种化合态.同时,随着基片温度的升高,晶粒尺寸增大且薄膜表面趋于平整.薄膜的光致发光在绿光带存在中心波长为530和550 nm两个峰,应该归因于主体材料ZnGeO中两个不同的Ge2+的发光中心.Films were deposited on Si substrates at different temperatures by RF magnetren sputtering and subsequently annealed in vacuum at 800℃. Well crystallized films were prepared successfully. The influences of substrate temperature on the structure, the componsition and the morphology of Zn2 GeO4films were investigated by X-ray diffraction, X-ray photoelectron spectroscopy （XPS） and atom force microscope. The results show that Zn2 GeO4 films grow with （220） preferred orientation with the increase of substrate temperature above 400℃, and the substrate temperature between 500 and 600℃ is suitable for GeO2 crystalline growth. XPS spectra show that the films contain four chemical compositions of Zn2 GeO4, GeO2, Ge and ZnO. Besides, with the increase of substrates temperature, the size of crystal grains increases, and the surface of films is smooth and continuous. The green emission consisting of two peaks centered at 530 and 550 nm, which is attributed to luminescence centers of Ge^2＋ substituting Zn^2＋ at different sites.

关 键 词：射频磁控溅射 Zn2GeO4 荧光体 

分 类 号：O484.41[理学—固体物理]