Synthesis of size-controlled pure copper nanoparticles for packaging interconnect

Copper nanoparticles used in microelectronic packaging industry are being given great attractive interest for its excellent power-handling capacity, high-thermal conductivity and reliability. In this article, we describe a route to synthetize pure, stable, monodisperse and size-controlled copper nanoparticles for microelectronic packaging use. In this work, copper nanoparticles were synthesized by reducing bivalent copper ions of copper acetate with ascorbic acid through a liquid phase reduction method, poly(N-vinylpyrrolidone) (PVP) was used as the protective agent. The size of copper nanoparticles can be controlled between 30nm and 80nm, and the produced copper nanoparticles were confirmed metallic copper with the formation of face-centered cubic (fcc). In this paper, we evaluated the influence in particle size by vary the reaction temperature, molar ratio of copper acetate to PVP concentration, optimum conditions were obtained through lots of experiments.