Copper oxide films can be reduced to copper with an atmospheric pressure argon and hydrogen plasma at temperatures between 25 and 300 C. A 50-nm-thick CuO layer on a Cu-coated Si wafer, 200 mm in diameter, can be fully reduced by the plasma in 200 seconds at 200 C. The activation energy for the reaction can be approximately 3.7 kcal/mol. X-ray photoelectron spectroscopy can show the copper oxide reduced to metallic copper.