Reliability Research on the Thermal Deformation and Stress of Metal Packaging With Low-Resistance Leads

Thermomechanical reliability of the metal packaging with low-resistance and high-electric current was discussed in this paper. Thermal deformations and stresses of packaging structures were studied by both experimental and numerical methods. Laser speckle interferometry was used as the experimental method to test the coefficient of thermal expansion of the metal composite leads and the thermal deformations of the entire packaging structures due to the temperature change from room-temperature to 150degC. ABAQUS/standard finite element (FE) code was used to simulate the thermal deformations and stresses of the packaging structures from room temperature to 150degC. The facts show that the results were in good agreement with those of experiments. It showed that the predicted thermal stresses and deformation in the working condition were qualitatively reliable. Moreover, the technique of elements deactivating and activating was used in FE analysis to simulate the manufacturing process of the packaging structures cooled from 779degC to room-temperature. Then the residual thermal deformations and stresses during the process were obtained.