Soldering deterioration of epoxy‐molded IC packages after moisture absorption

Abstract

Abstract Molding compounds for surface‐mount devices were studied by using various kinds of epoxy resins in a practical model compound with phenol resins as curing agents. The physical properties of the cured compounds were studied at 215°C to simulate the condition that they encounter during the soldering process that can relate to package cracks. The compounds that have low modulus at soldering temperature, low equilibrium water concentration, and good adhesion toward the die pad developed few cracks after soldering. The compounds from difunctional epoxy resins showed good durability, resisting this phenomenon. © 1994 John Wiley & Sons, Inc.