mc-Si thin films by hydrogen plasma assisted vacuum evaporation

Abstract

In the present work the effect of auxiliary plasma assistance on the structure, composition and optical gap of e-beam vacuum evaporated silicon thin films is investigated. The films were deposited over glass and Silicon wafer substrates, under argon-hydrogen plasma assisted, to verify also the effect of the H2 content, at substrate temperature of 250 °C. The species present in the plasmas were investigated using Optical Emission Spectroscopy, while the films were characterized by Raman, FTIR and UV-vis spectroscopy. The results show that the deposition of a-Si:H with high hydrogen content and mc-Si:H through the used low temperature plasma assisted vacuum evaporation. The relationship between crystallinity, optical band gap and species in the Plasma is discussed, considering the effect of molecular and atomic hydrogen content in the plasma, as well as a-Si chemical annealing theories.