Cu掺杂对ZnO纳米薄膜的结构及其光学特性的影响  

Study of structure and optical properties of Cu-doped ZnO nanofilms prepared by RF magnetron sputtering

作　　者：马书懿[1] 毛雷鸣[1] 马慧[2] 史新福[1] 周婷婷[1] 丁继军[1] 

机构地区：[1]西北师范大学物理与电子工程学院,甘肃兰州730070 [2]巢湖学院物理与电子科学系,安徽巢湖238000

出　　处：《西北师范大学学报（自然科学版）》2010年第1期37-42,共6页Journal of Northwest Normal University(Natural Science)

基　　金：国家自然科学基金资助项目(10874140);甘肃省自然科学基金资助项目(0710RJZA105);甘肃省高分子材料重点实验室开放基金资助项目(KF-05-03)

摘　　要：采用磁控溅射法(RF)在玻璃基底上制备了未掺杂和不同Cu掺杂浓度的ZnO薄膜.使用X射线衍射仪(XRD)、原子力显微镜(AFM)、扫描电子显微镜(SEM)分别对样品的形貌进行了表征,并对ZnO薄膜进行了应力分析.结果显示:所有样品都呈现出(002)衍射峰,有较好的c轴择优取向;所有样品出现有3个发光峰,分别对应于400 nm(3.14 eV,紫光),444 nm(2.78 eV,蓝光),484 nm(2.56 eV,蓝光).紫峰的存在与激子的存在有极大关系,而蓝光发射主要是由于电子从导带上向锌空位形成的浅受主能级上的跃迁.随着Cu掺杂量的增加,薄膜的带隙宽度Eg随之减小,样品光学带隙值由3.26 eV逐渐减小为2.99 eV.实验中还发现,随着Cu掺杂量增加,薄膜的透射率也随之减小.ZnO films doped with different Cu concentration are prepared on glass substrate by RF magnetron sputtering system. The structural and morphology of the samples are investigated by X- ray diffraction（XRD）, atomic force microscopy（AFM）and scanning electron microscopy（SEM）, and the stress in the ZnO thin films is analyzed. The results show that all the samples have a strong diffraetion peak and high preferential orientation in the （002）crystallographic direction. Three peaks have been observed from the PL spectra of the all samples, 395 nm（3.14 eV,violet）, 446 nm（2.78 eV,blue）and 488 nm（2.54 eV,blue）. It is concluded that the violet peak may correspond to the exciton emission, the blue emission corresponds to the electron transition from the bottom of the conduction band to the acceptor level of zinc vacancy; the optical test shows that the optical band gap Eg are decreased within the increase of Cu doped in ZnO, the band gap decrease from 3.26 eV to 2.99 eV gradually. It is also found that the transmission rate is decreased rapidly when the Cu concentration is increase.

关 键 词：AFM 光致发光 Cu掺杂ZnO薄膜 光学带隙 透射 

分 类 号：O484.41[理学—固体物理]