Properties of the Environmental-Friendly Si/Al Composite for Electronic Packages Fabricated by Squeeze Casting Technology

High reinforcement-content aluminum matrix composite,with a high thermal conductivity,the adjustable coefficient of thermal expansion（CTE）,low density and costs,have been extensively applied in electronic package.The Sip/Al composites were fabricated by squeeze casting technology.The microstructure observation showed that the composites were dense and macroscopically homogeneous,with no micro-holes and obvious defects.The linear CTEs of Sip/Al composites lay between（7.6～8.1）×10-6 ℃-1,and the thermal conductivity was larger than 100 W/（m·℃）.The composites also had lower density（2.4 g/cm3）,higher special strength and special modulus.The electroless nickel method was used to deposit a continuous and uniform layer on the composites surface,which can meet the reliability testing demands of the diodes with Sip/Al composite baseplate.