Methods of depositing a copper film onto the surface of a substrate from a supercritical solution containing copper-containing precursors having monoanionic bidentate and neutral monodentate ligands, which comprise contacting the substrate with the solution; heating the substrate to a temperature between about 60.degree. C. and less than 150.degree. C.; and forming a copper-containing film on at least a portion of the substrate surface. Also provided are copper-containing precursor compositions used therein.