Effect of particle size and milling process on the microstructure and thermal properties of Copper Silicon Carbide (CuSiC) composites for electronic packing application

Abstract

Shrinking size and increasing functionality of IC device has induced serious thermal problem. Good thermal dissipation, light weight and easy-to-process material, such as CuSiC, is a highly potential heat spreader material to cope thermal problem. Powder metallurgy method is chosen to fabricate CuSiC composite in this project. Fabrication of CuSiC powder starts with the mixing and milling of copper and SiC powder in different milling speed (150rpm, 200rpm, 250rpm) and time (2 hours, 5 hours, 10 hours), followed by compaction and sintering process to produce CuSiC pellets. Particle size analysis has carried out after the milling process. Results showed that by increasing the milling speed and time have reduced the powder particles size but causing agglomeration at the high milling condition. At high milling speed and time, the dimension of sintered CuSiC swell, density decrease and porosity increase. This is closely related to the morphology of the composite particles where the copper particles flattened become flakes form and agglomeration happened in the end of the milling. This inhibited good packing of powders particles. This high porosity then affected the thermal conductivity properties when the voids become a barrier to the heat conduction from one particle to another particle.