激发频率对VHF-PECVD制备微晶硅材料性能的影响

采用甚高频等离子增强化学气相沉积(VHF-PECVD)的方法制备了硅烷浓度分别为6％和7％， 随激发频率变化(40—70MHz)的氢化微晶硅(μc-Si∶H)薄膜材料.研究了材料的电学特性、 结构特性、沉积速率与激发频率之间的关系.结果发现材料的光敏性随频率的增加先降低后 提高，晶化率和沉积速率的变化趋势与之相反；在晶化率最高点，材料在(220)的晶向衍射 峰最高.并从光发射谱的角度研究了材料结构和沉积速率随频率变化的原因. 关键词： 甚高频等离子增强化学气相沉积 本征微晶硅 激发频率

Effect of excitation frequency on microcrystalline silicon materials prepared by VHF-PECVD

Hydrogenated microcrystalline silicon (μc-Si:H) materials was prepared by plasm a enhanced chemical vapor deposition (PECVD) at silane concentration 6% and 7% w ith changing excitation frequency (40—70MHz). Relationship between excitation f requency and electrical, structural characteristics and deposition rate of the m aterials was studied. The results indicate that the crystalline volume fraction (X_c) decrease firstly and then increase with the increase of excitati on frequency. But the photosensitivity and the deposition rate be have adversely with the change of excitation frequency. The reason of change of structure and deposition rate of thin films with excitation frequency was studied by optical e mission spectroscopy.