Study of pressure balance for Press-Pack IGBTs and its influence on temperature distribution

Pressure balance is a key technology for Press-Pack IGBT packaging, and is studied in this paper with its influence on the temperature distribution discussed in further when the device is turned on. By establishing the physical model of the Press-Pack IGBT device in the finite element simulation software, the influence of the internal flatness condition on the pressure balance is analyzed, and the variation of the average pressure difference with the flatness in different parallel scale of the chips is obtained. The thermal contact resistance and the electrical contact resistance parameters, which are dependent on the pressure, are then imported to perform the multi-field coupling, further investigating the effect of different pressure distributions on temperature distribution. The junction-case thermal resistance of the device with different flatness is compared experimentally. The results have demonstrated the influence of the flatness on the thermal resistance of the Press-Pack IGBT device.