Simulation of fatigue distributions for ball grid arrays by the Monte Carlo method

Any approach to qualification of advanced technologies during product devel opment must include an assessment of variation expected in product life ove r the life cycle. However, testing product design options in development, t o approach an optimal design is costly and time consuming. Hence, simulatio n of product life distributions for virtual qualification can be a valuable tool to evaluate and qualify design options. This paper presents a physics of failure-based approach to virtual qualification of advanced area array assemblies against solder fatigue failure. The approach applies Monte Carlo simulation to evaluate solder joint fatigue life distributions, given mate rial property Variations and manufacturing capabilities, Preliminary result s using the simple Engelmaier model as the basis of simulations are present ed. Simulation results are compared to data accumulated from two test envir onments and two ball grid array product types. The results reveal some of t he limitations of the Engelmaier model as a basis for simulation. They also show the potential of this approach to virtual qualification for design an d manufacturing capability assessment in development. (C) 2000 Elsevier Sci ence Ltd. All rights reserved.