Microstructures and Hydrogen Bonding Environments of a-Si: H Films Prepared by RF Sputtering in Pure Hydrogen

Abstract

Microstructures and correlated hydrogen bonding environments of a-Si: H films prepared by RF sputtering in pure hydrogen are investigated by TEM, FT-IR and optical absorption measurements. The films are more homogeneous than those prepared in an Ar/H₂ mixture; they are composed of fine grains and tend to have a microcrystalline structure with increasing gas pressure. Configurations of SiH₂ and SiH₃ increase with increasing voids, indicating that these are formed in the void regions on the surface of the grains. From these results, the roles of argon and hydrogen correlated to the microstructure of the films are discussed.