Analysis of Thermal Aging Characteristics of Silicone Gel for High-Voltage IGBT Packaging

Due to the increase in power loss, the internal junction temperature of the IGBT device increases. Long-term operation in a high junction temperature environment, IGBT device insulation packaging material silicone gel will undergo thermal aging, and its thermal stability and insulation characteristics will directly affect its service life after aging. In order to study the effects of thermal aging on the thermal stability and dielectric properties of silicone gels, this paper tested the physicochemical properties of silicone gel materials at different aging stages based on the accelerated thermal oxygen aging experiment of silicone gel materials, combined with FTIR and TGA. The experimental results showed that the main chain group of the silicone gel increased, the side chain group decreased after aging. The crosslinking reaction mainly occurred during the aging process, and the degree of crosslinking increased. The thermal stability decreased, and the insulation performance deteriorated. The experimental results of this paper lay an experimental foundation for the next step to study the thermal aging mechanism and modification of silicone gels.