Thermal Effects in Thin Silicon Dies: Simulation and Modelling

Detailed three-dimensional (3D) numerical thermal simulations are employed to clarify the influence of the key technological parameters and material properties on the thermal behaviour of ultra-thin chip stacking modules, wherein the heat removal from the thinned active dies is considerably hampered by benzocyclobutene layers. In particular, the impact of heat source area and thickness of silicon dies and benzocyclobutene layers is investigated in structures with one, two, and three thin silicon dies. The adoption of compact thermal models is then suggested as a solution to reduce the computational resources required to numerically analyse stacked-die modules.