A series of (0β-diketonate) copper(l) trimethylphosphine compounds has been prepared. These species exist either as liquids or low-melting solids at room temperature. The utility of these compounds as precursors for Chemical Vapor Deposition (CVD) of copper has been examined under a variety of conditions. High purity films with low resistivities have been deposited under a variety of conditions. Selective copper deposition was observed as a function of the substrate, precursor and substrate temperature. Evidence consistent with thermallyinduced disproportionation of the title compounds to form copper metal and copper(II) (β-diketonate)2 during deposition was observed.