VHF-PECVD低温制备微晶硅薄膜的拉曼散射光谱和光发射谱研究

采用拉曼散射光谱和PR650光谱光度计对VHF-PECVD制备的微晶硅薄膜进行了结构表征和在线监测研究.结果表明：功率对材料的晶化率（χc）有一定的调节作用，硅烷浓度大，微调作用更明显；SiH*的强度只能在一定的范围内表征材料的沉积速率，功率大相应的速率反而下降；I［Hα*］/I［SiH*］强度比值反映了材料晶化程度，此结果和拉曼散射光谱测试结果显示出一致性；I［Hβ*］/I［Hα*］的强度比表明氢等离子体中的电子温度随功率的增大而逐渐降低.关键词：甚高频等离子体增强化学气相沉积微晶硅拉曼散射谱光发射谱

A study of Raman and optical emission spectroscopy on microcrystalline silicon films deposited by VHF-PECVD

Structural properties of microcrystalline silicon films deposited by very high f requency plasma_enhanced chemical vapor deposition(VHF_PECVD) and on-line monit or were studied using Raman and optical emission spectroscopy. The results obta ined showed that the discharge power has a modulation function on crystalline volume fraction (χc) of materials. A larger silane concentration means a stronger modulation function. The intensity of SiH* peak can characterize the deposition rate in a certain range, however the higher power indicates the lower deposition rate, and the ratio of intensity Hα* to SiH* peak value reflects the extent of crystallinity which is consistent with the result obtained from Raman measurement. In addition, the ratio of I［Hβ *］／ I［Hα*］ indicates the decrease of electronic temperatur e in hydrogen plasma with the increase of discharge power.