椭圆偏振技术研究VHF-PECVD高速沉积微晶硅薄膜的异常标度行为

A spectroscopic ellipsometry study of the abnormal scaling behavior of high-rate-deposited microcrystalline silicon films by VHF-PECVD technique

采用VHF-PECVD技术高速沉积了不同生长阶段的微晶硅薄膜,通过椭圆偏振技术研究了生长过程中微晶硅薄膜表面粗糙度的演化.实验结果表明,沉积气压Pg=300Pa时,β=0.81,其超出标度理论中β最大值为0.5范围,出现异常标度行为.这表明微晶硅薄膜高速生长中还存在其他粗糙化增加的因素,此粗糙化增加的因素与阴影作用有关.

The scaling behaviour of surface roughness evolution of high rate deposited uc-Si： H by very high frequency plasmaenhanced chemical vapor deposition （VHF-PECVD） is investigated using spectroscopic ellipsometry （SE）. Films deposited at Ps = 300 Pa with deposition rate of 5 A/s, show abnormal scaling behavior with the exponent/3 of about 0.81, which is much larger than 0.5 of zero diffusion limit in the scaling theory. This implies that there are some roughening increasing mechanisms, and this roughening increasing mechanism is correlated with the shadowing effect.