微晶硅薄膜表面粗糙度的演化过程分析

Study on the Evolution of Microcrystalline Silicon Thin Film Surface Roughness

采用射频等离子体化学气相沉积(RF-PECVD)方法制备了沉积时间系列的微晶硅薄膜。采用椭圆偏振光谱仪(SE)和原子力显微镜(AFM)表征薄膜表面粗糙度,分析了表面粗糙度随沉积时间的演化行为。讨论了这两种测量手段在分析薄膜表面粗糙度时的差异。结果表明,采用SE拟合得到的表面粗糙度数值要大于采用AFM直接测量得到的结果。产生差异的原因,一是由于两种测量手段的测量机制不同;二是由于薄膜的结构不均匀导致薄膜表面形貌差异。另外,还发现这两种测量手段得到的表面粗糙度数值之间存在线性关系。

The intrinsic hydrogenated microcrystalline silicon films with different deposited time were prepared by radio frequency plasma chemical vapor deposition（ RF-PECVD） on glass substrates.The surface roughness of silicon thin films were analyzed by spectroscopic ellipsometer（ SE） and atomic force microscopy（ AFM） and a comparison of distinctive features of the above-mentioned methods in surface roughness measurement was presented.The results show that the surface roughness obtained by SE fitting is larger than results obtained using the direct AFM measurement.The reasons for the difference one is due to the measuring mechanism of two kinds of measuring methods,the other is due to the uneven film structure.However,there is a liner relationship between the two measurement methods.