高浓度Er/Yb共掺ZnO薄膜的结构及室温光致发光特性

采用射频磁控溅射方法制备了Er/Yb共掺ZnO薄膜,研究了退火处理对高浓度Er/Yb共掺ZnO薄膜的结构演化和光致发光(PL)特性的影响。X射线衍射分析结果表明:Er/Yb掺杂导致ZnO薄膜的晶粒细化及择优取向性消失,ZnO晶粒随退火温度的增加而逐渐长大。900℃退火时,出现Er3 、Yb3 偏析,退火温度高于1000℃时,薄膜与基体间发生了界面反应,1200℃时,ZnO完全转变为Zn2SiO4相。光致发光测量结果表明:高于900℃退火处理后,Er/Yb共掺ZnO薄膜在1540 nm附近具有明显的光致发光,发光强度在退火温度为1050℃时达到最大值;光致发光光谱呈现典型的晶体基质中Er3 离子发光光谱所具有的明锐多峰结构特征。此外,探讨了薄膜结构演化及其对光致发光光谱的影响。

Microstructures and Photoluminescence Properties at Room Temperature of Highly Er/Yb Co-Doped ZnO Films

Er/Yb co-doped ZnO films were fabricated by using radio-frequency reaction magnetron sputtering technique, and the influences of annealing temperature on the microstructures and photoluminescence (PL) properties of Er/Yb co-doped ZnO films were studied. The results of X-ray diffraction analysis showed that Er/Yb doping induced the crystallite refinement and the vanishment of preferential orientation of the ZnO films and the ZnO crystallite grain size grew with the increase of the annealing temperature. At 900 ℃, Er2O3 and Yb2O3 phases started to precipitate from the film. When the annealing temperature reached to 1000 ℃, a new phase of Zn2SiO4 due to the interfacial reaction of ZnO film with Si chip was observed. At 1200 ℃, ZnO film transited into Zn2SiO4 phase entirely. The PL measurement result indicatcd distinet PL spectra of the films about 1540 nm annealed above 900 ℃ were detected at room temperature and the maximum PL intensity was observed at 1050 ℃. The PL spectra showed typical sharp multi-peak structure characteristic owned by Er3+ ion PL spectra in crystal substrates. The effect on PL properties of the microstructure evolvement of the film was also discussed.