Effects of Chemical Composition and Morphology of Substrate Surfaces on Crystallinity of Ultrathin Hydrogenated Microcrystalline Silicon Films

Hydrogenated microcrystalline silicon (µc-Si:H) films of 10 nm thickness were prepared by the plasma-enhanced chemical vapor deposition method on glass substrates that had been coated by a layer composed of Si, O, and N. The chemical composition of this layer was changed systematically, and the resultant changes in the crystallinity of the µc-Si:H films were investigated using Raman scattering spectroscopy. We have found that SiN x layers inhibit nucleation of microcrystalline Si and the films deposited on them are dominated by an amorphous component, regardless of their stoichiometry. Substrate surfaces rich in Si–O bonds are preferable for the formation of high-quality µc-Si:H films. It has been also found that the morphology of the coated layers does not affect the crystallinity of the µc-Si:H films.