Enhancement of thermal conductivity of epoxy adhesives by ball milling copper flakes

In this study, copper flake was synthesized through wet ball milling the copper micro sphere, which was used as the filler of epoxy adhesives. The effect of ball milling time and dispersant on morphology of copper have investigated. The effect of ball milling with oleic acid as dispersant is more homogeneous than alcohol. The longer ball milling time, the higher proportion of Cu flake. When ball milling time comes to 2 hours, the thermal conductivity of copper adhesive filled with as-prepared Cu flake comes to threshold. Moreover, permissible voltage of copper adhesive filled with as-prepared Cu flake is reduced. This research provides an efficient way to synthesis Cu micro flake, which can used as the filler of thermal interface materials with high thermal conductivity for integrated circuit packaging application.