Evolution of infrared spectra and optical emission spectra in hydrogenated silicon thin films prepared by VHF-PECVD  

作　　者：侯国付 耿新华 张晓丹 孙建 张建军 赵颖 

机构地区：[1]Institute of Photo-electronics,Nankai University

出　　处：《Chinese Physics B》2011年第7期440-445,共6页中国物理B（英文版）

基　　金：Project supported by the National High Technology Research and Development Program of China (Grant No. 2009AA050602);the International Cooperation Project between China-Greece Government (Grant No. 2009DFA62580);the National Basic Research Program of China (Grant Nos. 2011CBA00705, 2011CBA00706, and 2011CBA00707)

摘　　要：A series of hydrogenated silicon thin films with varying silane concentrations have been deposited by using very high frequency plasma enhanced chemical vapor deposition （VHF-PECVD） method. The deposition process and the silicon thin films are studied by using optical emission spectroscopy （OES） and Fourier transfer infrared （FTIR） spectroscopy, respectively. The results show that when the silane concentration changes from 10% to 1%, the peak frequency of the Si-H stretching mode shifts from 2000 cm-1 to 2100 cm-1, while the peak frequency of the Si-H wagging-rocking mode shifts from 650 cm-1 to 620 cm-1. At the same time the SiH^＊/Ha intensity ratio in the plasma decreases gradually. The evolution of the infrared spectra and the optical emission spectra demonstrates a morphological phase transition from amorphous silicon （a-Si：H） to microcrystalline silicon （μc-Si：H）. The structural evolution and the p-c-SiH formation have been analyzed based on the variation of Ha and SiH^＊ intensities in the plasma. The role of oxygen impurity during the plasma process and in the silicon films is also discussed in this study.A series of hydrogenated silicon thin films with varying silane concentrations have been deposited by using very high frequency plasma enhanced chemical vapor deposition （VHF-PECVD） method. The deposition process and the silicon thin films are studied by using optical emission spectroscopy （OES） and Fourier transfer infrared （FTIR） spectroscopy, respectively. The results show that when the silane concentration changes from 10% to 1%, the peak frequency of the Si-H stretching mode shifts from 2000 cm-1 to 2100 cm-1, while the peak frequency of the Si-H wagging-rocking mode shifts from 650 cm-1 to 620 cm-1. At the same time the SiH^＊/Ha intensity ratio in the plasma decreases gradually. The evolution of the infrared spectra and the optical emission spectra demonstrates a morphological phase transition from amorphous silicon （a-Si：H） to microcrystalline silicon （μc-Si：H）. The structural evolution and the p-c-SiH formation have been analyzed based on the variation of Ha and SiH^＊ intensities in the plasma. The role of oxygen impurity during the plasma process and in the silicon films is also discussed in this study.

关 键 词：Fourier transfer infrared spectroscopy optical emission spectroscopy Si H bonding con-figuration oxygen impurity 

分 类 号：O484.41[理学—固体物理]