The influence of deposition time on the photoluminescent properties of SiOxCy thin films obtained by Cat-CVD from monomethyl silane precursor

•Siliconoxicarbide as a feasible candidate for silicon based opto-electronic devices.•Non-stoichiometry of Si-O bonding increases the probability of Si-C formation.•Intensive SiOxCy PL with a wide spectral range by the new deposition method.•Blue shifted photoluminescence spectra due to abetment of carbon content.•Origin of photoluminescence in SiOxCy explained by different defect mechanisms.