Relationship between Diamond Particle Size and Thermal Conductivity of Cu-Diamond Composites

Diamond-copper composites were fabricated by ultrahigh pressure sintering (UHPS) technology. The influence of diamond particle size on the microstructure,relative density and thermal conductivity of composites were investigated. The results indicated that the high relative density of more than 99% diamond-copper composite can be prepared by UHPS method. The composite thermal conductivity dramatically increased with increasing diamond particle size and the highest value of 675W/(m·K) were obtained when using 200μm diamond,which is much higher than those of traditional electronic packing materials. The Cu-diamond composite could fulfill the requirement of heat removal of the high-power electronic packaging devices.