Direct SPICE-like 3-D Electrothermal Simulation of Power HEMTs

Direct 3-D electrothermal equivalent model of power HEMT is presented in this paper. The model works with Synopsys HSPICE and 3-D RC network is build using MathWorks MATLAB. The thermal analysis of the multifinger power HEMT is performed. The features and limitations of the method are analysed and presented. Finite element method for thermal simulation usually uses separate simulation tool for thermal and electrical simulations. These tools must be properly synchronised and simulation is very time consuming for complicated 3-D structures. SPICE like circuit simulators are limited to electric models at a preselected temperature or the electrothermal feedback is provided only by an implemented simple single-pole RC equivalent network. Proposed method of 3-D electrothermal RC network combines simplicity of using only one simulation environment, while maintaining the accuracy of FEM 3-D electrothermal RC network is built from a simplified structure of multifinger HEMT using Mathworks MATLAB script. This script allows us to build 3-D RC network for variety of physical dimensions and different number of fingers of HEMT.