Electroless Plating of Copper on Silicon Wafer Via a Seedless, Environmentally Friendly Process

Copper is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. The copper thin film was made by an ELETROLESS PLATING method, to directly grow a copper film on the silicon substrate without using any seed layer. The mechanism and kinetics of the growth of the copper film were studied. Ascorbic acid was employed as the reducing agent, which is a cheaper and non-hazardous material comparing to hydrazine or formaldehyde as the commonly used reducing chemical. In addition, the effort also been made to produce a nanoparticles solution of copper through a similar process and can be used to fabricate a copper thin film directly by spin coating. The copper thin film we made can be potentially used as a conductive circuit, RFID tags, or front-contact metallization for silicon heterojunction solar cells.