Electroplating of copper/microdiamond composites and the effect of diamond surface functionalization

Abstract

Compositing diamonds with high thermally conductive metals, such as copper, have attracted much attention in recent years. In this study, we prepared copper/diamond composites by electroplating and investigated the effect of the surface functionalization of diamond on the interfacial adhesion of copper and diamond in the composite. Oxygen-containing groups were introduced on the diamond surface by a hydrothermal treatment and amino groups were further introduced using a silane coupling agent. Surface functionalization of diamond with both these groups led to drastically increased wettability against the copper sulfate solution and improved the interfacial adhesion of copper and diamond in the composite. Compared with that of the plating based on pristine diamond, the thermal conductivity of the platings based on diamond functionalized with oxygen-containing groups and amino groups increased by 42 and 31 W m[Formula: see text] K[Formula: see text], respectively. Thus, diamond surface functionalization effectively improved the adhesion at the copper/diamond interface in electroplated copper/diamond composites.