Xu Xiao-li, Ma Shu-yi, Chen Yan, Zhang Guo-heng, Sun Xiao-jing, Wei Jin-jun
College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2008 Sep;28(9):2028-32.
ZnO thin films with c-axis preferred orientation were prepared on glass substrates by radio frequency co-reactive magnetron sputtering technique, and the effect of the substrate temperature on the microstructure and the luminescence properties of the ZnO thin films was studied by X-ray diffractometry (XRD), scanning probe microscopy(SPM)and fluorescence spectrophotometer. The XRD patterns of the four ZnO samples prepared at different substrate temperatures were measured by XRD. figure which embodied the relation of full wave at half maximum (FWHM) and grain size of the four samples as a function of substrate temperatures was given out, too. It was concluded that the crystallization of the samples was promoted by appropriate substrate temperatures, the results consist with the AFM microscopic photos of the two samples. In addition, the photoluminescence (PL) spectra of the four samples were measured at room temperature. Violet peak located at about 400 nm, blue peak located at 446 nm and green peak located at about 502 nm were observed from the PL spectra of the four samples. With the rise of the growth temperature, the intensity of the violet peak and the blue peak increased sharply, and the intensity of green peak increased at the same time. It was concluded that the violet peak may correspond to the exciton emission, the blue peak was mainly attributed to the interstitial Zinc (Zn(i)) and the green emission peak must be related to the deep level defects of oxygen (Vo) in the crystal of ZnO films. Absorption property of the samples were researched by UV spectrophotometer, and the absorption spectrum of the film deposited at 150 degrees C and the (alpha h nu)2 versus h nu of the ZnO thin film were given. From the absorption spectrum, it could be observed that the spectroscopic data in UV region showed split peak and shoulder peak. With analysis of the absorption spectrum of the sample deposited at 150 degrees C, it was proved that our analysis of the photoluminescence mechanism was reasonable.
采用射频共反应磁控溅射技术在玻璃衬底上制备了具有c轴择优取向的ZnO薄膜，并通过X射线衍射仪（XRD）、扫描探针显微镜（SPM）和荧光分光光度计研究了衬底温度对ZnO薄膜微观结构和发光性能的影响。利用XRD测量了在不同衬底温度下制备的四个ZnO样品的XRD图谱。还给出了体现四个样品的半高宽（FWHM）与晶粒尺寸随衬底温度变化关系的图。结果表明，适当的衬底温度促进了样品的结晶，该结果与两个样品的原子力显微镜微观照片一致。此外，在室温下测量了四个样品的光致发光（PL）光谱。从四个样品的PL光谱中观察到位于约400nm的紫光峰、位于446nm的蓝光峰和位于约502nm的绿光峰。随着生长温度的升高，紫光峰和蓝光峰的强度急剧增加，同时绿光峰的强度也增加。得出紫光峰可能对应于激子发射，蓝光峰主要归因于间隙锌（Zn(i)），绿光发射峰一定与ZnO薄膜晶体中的氧的深能级缺陷（Vo）有关的结论。利用紫外分光光度计研究了样品的吸收特性，并给出了在150℃沉积的薄膜的吸收光谱以及ZnO薄膜的(αhν)2与hν的关系。从吸收光谱中可以观察到，紫外区域的光谱数据显示出分裂峰和肩峰。通过对在150℃沉积的样品的吸收光谱分析，证明了我们对光致发光机理的分析是合理的。
