Transient stages during the chemical vapour deposition of silicon carbide from CH3SiCl3/H2: impact on the physicochemical and interfacial properties of the coatings

Transient chemical vapour deposition experiments were produced from MTS/H-2 mixtures by varying the deposition temperature or the gas flow rates (Q(MTS) or Q(H2)) versus time. The gas phase, deposition rates and properties of the transient coating (phi(Tr)) were investigated and adhesion assessments of SiC/phi(Tr)/SiC bilayers were performed by scratch testing. Transient stages resulting from a decrease of Q(MTS) or temperature lead to silicon co-deposition, but do not affect interfacial properties. Transient stages resulting from a decrease of Q(H2) eventually lead to carbon co-deposition. Thick and continuous carbon interlayers lead to a poor adhesion whereas thin and discontinuous layers do not. (C) 2012 Elsevier B.V. All rights reserved.