The study of the substrate temperature depended growth properties of microcrystalline silicon films deposited by VHF-PECVD method

摘要

In this paper, we have measured the temperature depended growth properties of hydrogenated micro-crystalline silicon (μx-Si:H) films, prepared by very high frequency plasma-enhanced chemical vapor deposition (VHF-PECVD) from SiH_4 and H_2 gas mixtures. And, a 1D plasma model coupled with a well-mixed reactor model is used to simulate the growth process, in which concentrations of gas phase species, the crystalline orientation, the hydrogen content and the deposition rate are calculated. It suggests that the increasing surface fraction of the dangling bonds with the increase of substrate temperatures is responsible for the increase in the grain sizes. At the same time, the observed variations of the X-ray-diffraction intensities and the deposition rates of the films with temperature result from the differences in the growth rates of the facets.