对高H2稀释比条件下热丝CVD法制备GeSi薄膜的工艺参数对薄膜的键结构的影响进行了研究。用Raman谱和FT-IR谱对薄膜中非极性键(Ge—Ge、Ge—Si和Si—Si)相对含量的变化和极性键(Ge—H、Ge—H2、Si—H等H键)相对含量的变化进行了分析。研究结果表明,热丝CVD工艺参数对制备的GeSi薄膜中非极性键和极性键的影响规律是不同的。热丝温度和锗烷硅烷流量比(RS/G)对非极性键相对含量的变化均有影响。随着热丝温度上升Ge—Si和Si—Si相对含量均增加。随着RS/G增加Si—Si相对含量一直增加,Ge—Si相对含量先增加,当RS/G〉1.4时开始下降。但热丝温度和RS/G对H键的影响规律有很大不同:随着RS/G增加,Si—H键的相对含量增加,Ge—H和Ge—H2键的相对含量减少,而热丝温度对H键相对含量基本无影响。
In this paper,effect of process parameters on bonds structure of GeSi films prepared by hot-wire CVD with high hydrogen dilution ratio is studied.Raman spectroscopy and Fourier transform Infrared spectroscopy are used to analyze the relative contents of nonpolar bonds(Ge—Ge,Ge—Si,Si—Si)and the relative contents of hydrogen bonds(Ge—H,Ge—H2,Si—H),respectively.It is found that effects of hot-wire temperature (Tw)and SiH4/GeH4ratio(RS/G)on nonpolar bonds and hydrogen bonds are different.Twand RS/Gboth have effects on relative content of nonpolar bonds.Relative contents of Ge—Si and Si—Si increase with Twincreasing.With RS/Gincreasing,relative content of Ge—Si increases but decreases when RS/G1.4,while relative content of Si—Si increases all through.But Twhas no effects on relative contents of nonpolar bonds while RS/G affects obviously.