Copper chemical vapour deposition on organosilane-treated SiO2 surfaces

Abstract Copper thin films were grown on SiO2 substrates by chemical vapour deposition using the precursor (2-methyl-1-hexene-3-yne)Cu(1,1,1,5,5,5-hexafluoroacetylacetonate) ((MHY)Cu(hfac)) and were examined by scanning electron and atomic force microscopy. The affinity for copper chemical vapour deposition of the substrate surface is higher after the formation of self-assembled monolayers of organosilanes onto the substrate surface. Furthermore, the affinity is greatly enhanced by a subsequent UV light irradiation of the organosilane monolayer, in air, prior to deposition. The dependence of film morphology and statistical surface parameters on substrate temperature and amount of vapour precursor introduced during deposition, provide information for the optimisation of external parameters towards obtaining a thin yet continuous film. Self-assembled monolayers of organosilanes can be used for a selective metallization of SiO2 substrates by copper chemical vapour deposition, in addition to acting as ultrathin barriers which prevent copper diffusion into the SiO2, thus opening a route for a technology useful in microelectronic industrial applications.