Crack Effect on the Equivalent Thermal Conductivity of Porously Sintered Silver

摘要

Characterizations of equivalent thermal conductivity (ETC) of sintered silver is an important topic due to the thermal-mechanical reliability requirements of electronic packaging. In this paper, the effect of various types of cracks on the ETC of sintered silver are discussed. A numerical method to simulate the heat transfer behaviors of porous sintered silver containing the crack effect is presented. The results show that the ETC of sintered silver depends significantly on the crack length, crack orientation, porosity, and pore shape. Theoretical formulae to estimate the ETC of sintered silver are also presented, in which the effects of arbitrary crack depth, arbitrary crack orientation, arbitrary porosity, and arbitrary pore shape factor on ETC are included. It has been found that the influence of the side edge crack on the reduction of the ETC of sintered silver is the most obvious compared with the center crack and the upper edge crack. This study presents a quantitative method to evaluate the crack effect on the ETC of porous sintered silver.