Characterization of Thermally Aged Silicone Gels for Power Semiconductor Modules

This paper presents a comprehensive study on the evaluation of silicone gels for power semiconductor module packages. Silicone gels are widely used as encapsulation materials serving many functions in the package such as preventing partial discharges or protecting inner module components from environmental impact. Five commercial gels were subjected to thermal aging at both extreme low and high temperature (-50 deg C and 200 deg C, respectively). Results of FTIR, DSC, TGA and as well as hardness measurements are presented. The results show the degradation and change of the material composition and properties through thermal load which supports selecting the most suitable silicone gel per application and the required working condition.