Advanced reliability study on high temperature automotive electronics

To ensure high reliability for advanced automotive electronics, investigation and understanding on the failure mechanisms under harsh conditions are needed. New methods and technologies for improved reliability and increased lifetime should be developed. In this paper, an investigation on the effect of high temperature aging on the thermomechanical properties, microstructure of the molding compounds and the reliability issues of the packages is presented. Experimental characterizations of aging effect on the packaging materials and the package were carried out. DMA, TMA and TGA were used to measure the moduli, coefficients of thermal expansion (CTE), and the shrinkage induced by the aging process. Construction analysis was performed to examine the aging effect on the microstructure of the aged samples. It is found that aging has significant influence on the rubbery modulus, the glass transition temperature (Tg) and the strength. Aging-induced shrinkage was also found. Oxidation is believed to be one of the main mechanisms for the degradation of the material properties.