Fabrication of SiC-Type Films Using Low-Energy Plasma-Enhanced Chemical Vapor Deposition (PECVD) and Subsequent Pyrolysis

Siliconcarbide (SiC) is a promising material for a variety ofapplications in the biomedical, aerospace, and energy industries.Solution-phase techniques have long been used to deposit precursorfilms prior to pyrolysis into SiC, but they tend to face difficultieswith substrate compatibility and the use of toxic solvents. In thisstudy, we introduce a solventless synthesis route for fabricatingSiC-type films by depositing an organosilicon copolymer poly(vinylphenyldimethylsilane-co-divinylbenzene)(p(VPDMS-co-DVB)) film using low-energy plasma chemical vapor deposition(PECVD) followed by subsequent pyrolysis. The chemical structure ofthe film was systematically studied in situ during pyrolysis as afunction of temperature using diffuse reflection infrared Fouriertransform spectroscopy (DRIFTS). The majority of the functional groupswere found to have disappeared by a temperature of 800 degrees C, withmost of the mass loss occurring between 350 and 520 degrees C. Thermogravimetricanalysis (TGA) was used to measure the loss of mass as the pyrolysistemperature was increased, and the observed pyrolysis rates were comparedto estimates of such rates from the DRIFTS analysis. Our proposedsynthesis route provides a scalable and solventless method of producingSiC-type ceramic films for such applications as high-temperature sensorsand membranes.