**5. Conclusions**

The clamping force distribution within PP IGBTs is quite important because it affects not only the electrical and thermal characteristic but also the reliability. Many factors may affect the clamping force that has been classified and analyzed through the finite element method in this chapter, and the simulation results are well presented and explained. Based on the simulation results, we know that we should pay more attention to the thermal stress, machining accuracy, internal layout, and electrode design during the structure design process, especially the thermal stress. The disc spring is very important for the PP IGBT application, and this factor also should be considered during the mechanical simulation. The slim plate can be omitted in the mechanical simulation that it is too thin and its contribution to the clamping force distribution is very limited.

The clear classification and analysis of all the factors that affect the clamping force distribution can give a guideline not only for the semiconductor manufacturers to optimize the structure design but also for users to take full advantages of the PP IGBTs.
