IR laser-induced co-decomposition of dimethyl selenide and trisilane: Gas-phase formation of SiSe and chemical vapor deposition of nanostructured H/Si/Se/C polymers

Chemical changes in IR laser irradiated gaseous mixtures of dimethyl selenide and trisilane have been diagnosed by laser-induced fluorescence (LIF) of transient species and by FTIR, Raman, photoelectron spectroscopy and electron microscopy of the final solid products deposited from the gas phase. It is revealed that decomposition of both compounds leads to gas-phase formation of SiSe and deposition of solid nanostructured polymeric materials. We present indirect evidence on the presence of SiSe bonds in these polymers by revealing that these polymers undergo hydrolysis in air to H2Se and CH3SeH, which converts them to solid silicone-based films containing elemental selenium. Plausible reactions taking place in the gas phase and upon exposure of solids to air are suggested.