沉积温度对a-SiN_x∶H薄膜PL峰的影响

Photoluminescence of LPCVD Si-Rich SiN_x Films Depositedat Different Temperatures

在3.75eV的激光激发下，利用LPCVD在800-950℃不同温度下沉积富硅的SiNx薄膜中，在室温下观测到1～5个高强度可见荧光的发射．通过TEM，IR，XPS等的分析研究表明，文中所获样品为纳米硅镶嵌结构的a-SiNx：H薄膜．PL峰数目及其各峰的强弱与生成薄膜过程中反应气体SiH2Cl2的分解速率、沉积温度、SiNx生长过程有关，还与薄膜中纳米硅的团簇密度、尺寸大小以及各种不同类型的缺陷态种类和密度有十分重要的关系．

Silicon-rich silicon nitride thin films prepared by LPCVD technique show visible photoluminescence （PL） emission at room temperature with one to five separate peaks. Based on TEM, IR,and XPS,we find that the films have the mosaic structure of silicon nanoclusters embedded in a silicon nitride solid. By choosing different deposition temperatures during the preparation of the samples,we can change the microstructure of the thin films and the defects in them,which causes the changes of the PL spectrum. This then provides us information about the luminescence mechanics of the silicon nitride thin films.