Multiphysics Characterization of Transient Electrothermomechanical Responses of Through-Silicon Vias Applied With a Periodic Voltage Pulse

摘要

Multiphysics characterization of transient electrothermomechanical responses of multilayered stacked through-silicon vias (TSVs) is performed with a modified hybrid time-domain finite-element method. Temperature dependence of most material parameters involved is considered, such as electrical and thermal conductivity, the thermal expansion coefficient, and Young's modulus. Transient temperature and thermal stress accumulation processes are studied in detail for various copper, polycrystalline silicon, and tungsten/polycrystalline silicon TSVs, with different periodic voltage pulses applied. It is shown that there are significant differences in the transient temperature and thermal stress responses among the three types of TSVs, which are all very sensitive to the variation of the surrounding silicon oxide isolation thickness. The algorithm and analysis will be useful in the design of stacked TSVs with high reliability.