Improved interfacial adhesion between diamond film and copper substrate using a Cu(Cr)–diamond composite interlayer

Abstract

Large area diamond films were successfully fabricated on copper (Cu) substrates by first electroplating a Cu–diamond composite layer with a tiny amount (0.05–0.1wt.%) of chromium (Cr) in Cu and then growing the continuous diamond film on the composite interlayer by hot-filament chemical vapor deposition (HFCVD). The interfacial characteristics were investigated in detail by scanning electron microscopy and indentation test. The results show that using this new approach, the diamond coating could be firmly adhered to the substrate during rapid cooling after HFCVD. Doping Cr into the Cu–diamond composite interlayer and anchoring the diamond particles deep in the Cu(Cr) matrix are responsible for the much improved interface adhesion between coating and substrate.