Convection modelling of flip chip and wirebond surface mounted modules

Forced convection and conjugate heat transfer of ceramic surface mount modules is studied by computational fluid dynamics technique. Both capless and capped flip chip and cavity down wirebond interconnections are considered in this study. Computational and experimental data of thermal resistance of capless flip chip modules are compared to assess the accuracy of the model. Thermal resistances, heat rate distributions, local temperature and heat transfer coefficient distributions are presented to study the detailed convective characteristics. Results show that the flip chip interconnections have higher thermal performance than the wirebond surface mount packages. It is also found that local heat transfer coefficients are needed for accurate prediction of temperature distributions.