Infrared absorption of porous silicon layers and silicon particle films

Using TaC filaments for a hot-wire chemical vapor deposition (HWCVD) compact material (substrate temperatures 220°C) and porous, non-compact or void-rich layers (120°C) were produced in a silane-hydrogen atmosphere in the pressure range from 1 Pa to 30 Pa. For high pressures the adhesion of the layers was weak. In this case the thus pulverized silicon particles could be removed from the substrate by an ultrasonic process in an isopropanol bath. The suspension of these silicon particles was spread to form a continuous film, namely a "particle-film". The infrared (IR) spectra of the compact solid, the original porous layers and a series of temper stages of the particle-films are compared and discussed. The role of H and O atoms in the silicon network is investigated. Thus those structural properties, which may be found out by infrared tools, e.g. the bonding configurations of the Si related bonds of the said materials and some possible chemical reactions are explained