Creep behaviors of flip chip on board with 96.5Sn-3.5Ag and 100In lead-free solder joints

Abstract

Time-dependent nonlinear analysis of lead-free solder bumped flip chip on printed circuit board (PCB) assemblies subjected to thermal cycling condition is presented in this study. Two different lead-free solder alloys are considered, namely, 96.5wt%Sn-3.5wt%Ag and 100wt%In. The 62Sn-36Pb-2Ag solder alloy is also considered to establish a baseline. All of these solder alloys are assumed to obey the GarofaloArrhenius steady-state creep constitutive law. The shear stress and shear creep strain hysteresis loops, shear stress history, and shear creep strain history at comer solder joint are presented for a better understanding of the thermal-mechanical behaviors of lead-free solder bumped flip chip on PCB assemblies.