等离子体增强CVD法沉积的微晶硅薄膜的微结构研究(英文)

Microstructure of Microcrystalline Silicon Film by Plasma Enhanced CVD

本文系统研究了PECVD法沉积μc-Si薄膜中衬低温度、氢气稀释率和射频功率等参数对μc-Si薄膜结构特性的影响。表明:随着衬低温度的增加、氢气稀释率的增大、射频功率的提高,薄膜的晶化率增大。沉积薄膜的晶化率最大可达80%,表面粗糙度大约为30nm。通过对反应过程中的能量变化进行了分析,得到反应为放热反应,且非晶结构对沉积参数比较敏感。

Intrinsic microcrystalline silicon thin films were deposited on the glass substrate at pressure of 133.3Pa by plasma enhanced chemical vapor deposition （PECVD） using SiH4/H2 plasma. The effects of substrate temperature, hydrogen dilution and radio-frequency （RF） power on the structural properties of μc-Si films have been systematically investigated. The largest crystalline volume fraction is approximately 80% , and the surface roughness is about 30nm. With the increase of substrate temperature, the crystalline volume fraction increased and the maximum values of 34. 2% at 400℃ was achieved. A larger hydrogen dilution ratio and relatively high RF power would increase the crystalline volume fraction. To explain these experimental phenomena, we calculated the energy changes of the reaction process and found it an exothermic reaction. The amorphous structure is more sensitive to the substrate temperature, silane flow rate and RF power.