Improvement of lifetimetime prediction of silver sintered material in automotive power devices

In recent years, studies and developments of power devices are proceeding with the electric vehicles spreading. In this study, authors proposed an approach that considers fatigue characteristics to determine the lifetime of silver sintered materials for mounting SiC semiconductors. We obtained the Manson-Coffin rule from the thermal cycle test using the Si chip joined a substrate with the silver sintered material and the analysis under the same conditions as the test. We demand the lifetimetime predicted from the Manson-Coffin rule used analysis, however the result didn't agree with the test result. Then, improving the model for analysis and predicting the lifetimetime considering the ratchet phenomenon again, we obtained the result of lifetimetime close to the test result. The approach in this study promise to achieve the reliability evaluation of silver sintered materials more accurate.