蓝光ZnO薄膜的特性研究  

Properties of Blue Luminescence ZnO Thin Film

作　　者：朋兴平[1] 杨扬[1] 耿伟刚[1] 杨映虎[1] 王印月[1] 

机构地区：[1]兰州大学物理科学与技术学院,甘肃兰州730000

出　　处：《发光学报》2005年第4期531-534,i0002,共5页Chinese Journal of Luminescence

基　　金：国家自然科学基金资助项目(50272027)

摘　　要：采用反应溅射法在n型硅(100)衬底上制备了ZnO薄膜,分别用X射线衍射仪、原子力显微镜和荧光分光光度计对样品的结构、表面形貌和光致发光特性进行了表征。X射线衍射结果表明,实验中制备出了应变小的c轴择优取向的ZnO薄膜;原子力显微镜观察表明,薄膜表面平整,颗粒大小约为50 nm,为柱状结构,颗粒垂直于硅衬底表面生长;在室温光致发光(PL)谱中观察到了波长位于434 nm处的较窄的强蓝光发射峰,该蓝光峰的半峰全宽约为50 m eV。对蓝光峰的发光机制进行了讨论,并推断出该蓝光峰来源于电子从Zn填隙缺陷能级向价带顶跃迁。Over the past few years, wide and direct band gap semiconductors have been intensively studied for their application as blue and ultraviolet light emitters. As a wide gap semiconductor, ZnO has a wide band gap of 3.37 eV and a large binding energy of 60 meV. Therefore, ZnO is considered as one of the most promising candidates for short wavelength optoelectronics devices, and it is very important to conduct further studies of the properties of ZnO thin films. An un-doped zinc oxide thin film was prepared by radio frequency （RF） reactive co-sputtering on silicon （100） substrate. Sputtering target was metal zinc （99.99%）, the sputtering gas is a mixture gas of argon （99.97%） and oxygen （99.95%）, the partial pressure ratio of oxygen is 0.4. The structure, surfaces morphology and PL spectra of the sample were characterized by X-ray diffractometer, atomic force microscopy （AFM） and fluorescent spectrophotometer, respectively. The X-ray diffraction patterns indicated that the film has highly c-axis orientation and low biaxial compressive stress （2.8 × 10^8 N/m^2 ）, the 2θ angle of （002） diffraction peak is 34.48 ° and the full width at half maximum is 0. 306°. The grain size of the sample is about 50 nm. A strong blue emission peak and a weak violet emission peak located at 434 nm and at 414 nm are observed in the photoluminescence （PL） spectrum when exited with 325 nm wavelength （He-Cd） at room temperature. The full width at half maximum of blue emission peak is only 50 meV. We assigned that the violet emission and blue photoluminescence peaks originate from Zn vacancy and Zn interstitial defects, respectively.

关 键 词：ZNO薄膜 硅衬底 光致发光 射频反应溅射 

分 类 号：O472.3[理学—半导体物理] O482.31[理学—物理]