Production of amorphous silicon thin films using Chemical Vapour Deposition

Abstract

Hydrogenated amorphous silicon thin films have been prepared using the Plasma Enhanced Chemical Vapor Deposition (13.56 MHz PECVD) technique over two kinds of substrate, boro-silicate glass and double-sided polished silicon wafers. The films were grown from a gas mixture of silane (SiH4) gas and hydrogen (H2). The content of hydrogen is a critical factor in hydrogenated amorphous silicon films due to the necessity to control the Staebler Wronski effect. In this study, the effect of deposition temperature and time over the film thickness and the content of bonding configurations of hydrogen in the film has been investigated. It was concluded that the thin films produced at higher temperatures have a larger concentration of bonded hydrogen, but this does not affect the topographical structure. It has also been proved that the thickness of the film increases with the deposition time.