The effect of relatively low hydrogen dilution on the properties of carbon-rich hydrogenated amorphous silicon carbide films
Carbon-rich hydrogenated amorphous silicon carbide (a-Si1-xCx:H) films were deposited by plasma enhanced chemical vapor deposition (PECVD) using silane, ethylene and hydrogen as gas sources. The effect of relatively low hydrogen dilution on the properties of as-deposited samples was investigated. A variety of techniques including Scanning Electron Microscope (SEM), Fourier transform infrared spectroscopy (FTIR), Raman scattering (RS), UV-VIS spectrophotometer and photoluminescence (PL) spectroscopy were used to characterize the grown films. The deposition rate decreases with hydrogen dilution. The silicon to carbon ratio increases slightly with the addition of hydrogen. The phenomenon can be attributed to the dissipation of power density caused by hydrogen dilution. Raman G peak position shifting to a lower wave number indicates that hydrogen dilution reduces the size and concentration of sp2 carbon clusters, which is caused by the etching effect by atomic hydrogen. The optical band gap, which is controlled by the sp2 carbon clusters and Si/C ratio, changes unmonotonously. The as-deposited samples exhibited a blue-green roomtemperature (RT) PL well visible to the naked eye with UV excitation. The PL band can be attributed to the radiative recombination of electron-hole pairs within small sp2 clusters containing C=C and C-H units in a sp3 amorphous matrix.
Zhe Li Juncao Bian Haiyan He Xiwen Zhang Gaorong Han
State Key Laboratory of Silicon materials, Zhejiang University, Hangzhou 310027, PR China
国际会议
3rd International Photonics & OptoElectronics Meetings(第三届国际光子与光电子学会议 POEM 2010)
武汉
英文
1-7
2010-11-03（万方平台首次上网日期，不代表论文的发表时间）