Study On Electro-Thermo-Mechanical Characteristics Of Semiconductor Power Devices With Graphene Layers

With the development of three-dimensional packaging, power density of power devices with ever-increasing integration. The reliability problems of semiconductor power devices are becoming increasingly prominent. In this case, electro-thermo-mechanical characteristic of these devices is needed to be studied urgently.The study on electro-thermo-mechanical characteristic of semiconductor power devices with graphene layers in this thesis is based on mixed nonlinear finite element method. Considering the temperature-dependent material parameters, the nonlinear electro-thermo-mechanical coupling is solved by the direct iteration method. Based on finite element method (FEM), time differential is replaced by time difference, solving steady-state and transient-state problems. The analysis method is compared to the commercial simulation software and the results of other papers in typical examples, to ensure that the analysis method is of accuracy for the model of multiple-gate HEMT (High Electron Mobility Transistor) with graphene layers.Then, using the above analysis method, in-depth study for steady-state and transient-state characteristic of multiple-gate HEMT with graphene layers is done in this thesis. The results show that graphene layers can reduce the maximum temperature rise and thermal stress which is caused by temperature rise significantly. This thesis compares numerical results of multiple-gate HEMT with graphene layers under different conditions respectively. Clear guidance is given for the reasonable application of graphene layers.