Warpage Behaviors of System-in-Packages on a Substrate Strip

Abstract In this paper, the impact of two different types of warpage, strip warpage and system-in-packages (SiP) module warpage, are considered and studied, both experimentally and numerically. An advanced material characterization method is also conducted to study the curing reaction and Pressure-Volume-Temperature-Cure (PVTC) kinetics of the packages. The curing reaction of epoxy resins, as a function of temperature and activation energies, is experimentally determined. During the curing process, the viscosity of epoxy resins change with temperature and conversion rate. The Castro-Macosko model is adopted to describe the rheological properties of epoxy resins. Experimentally, we have prepared substrate strip samples with different component density and molding compound materials. Each substrate strip contains eighteen system-in-packages. The warpages of all substrate strips and all the system-in-package modules were measured, compared, and correlated.