中文摘要：

利用电子束蒸发技术在p型硅衬底上沉积了200 nm厚的CeO2薄膜样品,将样品置于弱还原气氛中高温退火后,观察到薄膜在385,418 nm以及445 nm左右出现三个明显的发光峰。结合激发光谱、吸收光谱以及XRD分析表明：CeO2薄膜在高温下容易发生失氧反应,出现Ce4＋→Ce3＋离子转变,Ce3＋离子在紫外光的激发下,电子由O2p跃迁到5d能级,再由5d能级向4f能级跃迁,从而产生强烈的蓝紫外发射,而445 nm左右的发光峰则来自于SiO2薄膜的缺陷发光。样品选择9001 200℃不同温度退火,并且在1 200℃下进行了不同时间的退火。研究结果显示：在1 200℃下进行2 h的退火,薄膜发光强度达到最大。

英文摘要：

CeO2 films were deposited on p type Si wafers by e-beam evaporation technology.Three photoluminescence peaks which located around 385,418 nm and 445 nm were obtained after annealing in weak redu-cing atmosphere at high temperature.It was indicated that CeO2 films transferred to amorphous state as the valence conversion of Ce4＋→Ce3＋,which was induced by reducing atmosphere annealing.The PL spectrum of 385 nm and 418 nm was assigned to the transition from 5d energy level of Ce3＋ ions to 2F7/2 and 2F5/2 manifolds of 4f energy level,respectively,while the peak around 445 nm was assigned to the O vacancies of SiO2.Furthermore,the changes of PL intensity in CeO2 films annealed with different temperature and time were also investigated.The maximum PL intensity was obtained after the films annealing at 1 200 ℃ for 2 h compared with other temperature and time.It was indicated that valence conversion of Ce4＋→Ce3＋ was enhanced by increasing annealing temperature and time,that is,the PL intensity of the films was also enhanced because of the increasing of Ce3＋ ions,however,the energy transfer between Ce3＋ and Ce3＋ ions,occurred as excessive Ce3＋ ions were formed in the films,resulting in concentration quenching.