Characterization of SiC and Si3N4 coatings synthesized by means of inductive thermal plasma from disilane precursors

Abstract

AbstractThe synthesis of SiC (and/or Si3N4) in an inductive thermal plasma from liquid disilane precursor is described in this paper. One goal of the process presented hereafter is the valorization of a liquid disilane fraction, which is a by‐product of the silicone industry. The liquid precursor is atomized in the core of the thermal inductive plasma and decomposed in the high‐temperature zone. The coating grows on the substrate according to the thermal plasma chemical vapor deposition (CVD) process. The resulting synthesized materials are investigated by means of X‐ray diffraction, scanning and transmission electron microscopy, and nuclear magnetic resonance. The composition of the material synthesized is studied as a function of process parameters, such as the plasma gas nature and its composition, the atomization gas flow rate and the plasma reactor pressure. Control over the composition of the synthesized material composition, as well as the coating microstructure, can be achieved by an appropriate adjustment of the experimental parameters. Nanostructured α/β‐SiC and α/β‐Si3N4 can be synthesized successfully with such a thermal plasma process. The deposition rate reached with such a technology is more than 20 μm min−1, which is two to three orders of magnitude higher than that of the conventional CVD method. Copyright © 2001 John Wiley & Sons, Ltd.