Fatigue lifetime prediction of a novel interface material with plastic failure for power electronics packaging

Sintered nanoscale silver paste was used as thermal interface material in an electronic package. Based on the microstructure of the sintered silver paste, die shear stress-strain curves and thermal cycling test results, a model combined with the model of Navarro-de los Rios and small cracks interaction physical model is put forward to predict the thermal fatigue lifetime of the sintered nanoscale silver paste. Meanwhile, Die-shear strength experiments instead of thermal loading were conducted using Al₂O₃ and AlN substrates to check the model.