Thermal expansion behavior of the electroless copper coated Cu-SiCp composites fabricated via the conventional powder metallurgical technique

Abstract

The introduction of the metal matrix composites as the advanced electronic packaging materials is highly anticipated because their thermal properties can be engineered to match those of semiconductors, ceramics substrates and optical fibers. Among these advanced packaging materials, silicon carbide particles reinforced copper matrix (Cu-SiCp) composites are highly rated due to the high thermal conductivity of copper and low coefficient of thermal expansion (CTE) of silicon carbide. However, the Cu-SiCp composites fabricated via the conventional powder metallurgy (PM) technique usually have immature thermophysical properties due to the weak bonding between the copper matrix and the SiCp reinforcement. In order to improve the bonding between the two constituents, the SiCp were coated with copper via electroless coating process prior to PM fabrication processes. Based on the experimental results, The CTE and porosity of the Cu-SiCp composites were significantly affected by the volume fraction of SiCp. Furthermore, the CTE and porosity of the Cu-Coated Cu-SiCp composites were significantly lower than the non-Coated Cu-SiCp composites. These differences were mainly contributed by the nature of the bonding between the copper matrix and SiCp reinforcement.