Fabrication and characterization of high dense Mo/Cu composites for
electronic packaging applications
electronic packaging applications
(School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China)
Abstract: For electronic packaging applications，Mo/Cu composites with volume fractions of 55%−67% Mo were fabricated by the patented squeeze-casting technology. The microstructures and properties of the Mo/Cu composites were investigated. The results show that Mo particles are homogeneous and uniformly, and the Mo-Cu interfaces are clean and free-from interfacial reaction products and amorphous layers, the densifications of the Mo/Cu composites are higher than 99%. The mean linear coefficients of thermal expansion (20−100 ℃) of Mo/Cu composites range from 7.9 to 9.3×10−6/℃ and decrease with increasing volume fraction of Mo. The experimental coefficients of thermal expansion agree well with predicted values based on Kerner’s model. The thermal and electric conductivities of Mo/Cu composites are in range of 220−270 W/(m∙℃) and 22−28 MS/m, respectively, and decrease with increasing volume fraction of Mo. The achievement of higher thermal and electric conduction is attributed to the full densities and high purity, which are obtained through the cost-effective squeeze-casting technology processes.
Key words: Mo/Cu composites; densification; thermal expansion coefficient; thermal conductivity; electric conductivity