Si/C Phases from the IR Laser-induced Decomposition of Silacyclobutane and 1,3-Disilacyclobutane

CO₂ laser-induced infrared multiphoton decomposition (IRMPD) and SF₆ photosensitized decomposition (LPD) of silacyclobutane (SCB) and 1,3-disilacyclobutane (DSCB) in the gas phase results in the very efficient deposition of Si/C/H and SiC materials, and it is inferred that the process is dominated by formation of transient silene; silene rearrangement to methylsilylene; silene and methylsilylene dehydrogenation; and polymerization of SiCH_n (n < 4) species. The deposits are sensitive to oxygen. Decomposition and SiC formation are favoured with IRMPD experiments conducted with high-energy fluxes. The laser technique is promising for low-temperature chemical vapour deposition of amorphous SiC.