Thermal modelling of multifinger GaAs/GaN FETs using SPICE

Abstract

A simple thermal model is presented to estimate the junction temperature in multi-finger GaAs and GaN high electron mobility transistors (HEMTs). The model is implemented in SPICE by treating heat flow as analogous to the flow of electric current. The model enables a comprehensive study of different layout possibilities for devices. Results from 3D Finite Element Model (FEM) simulation and from Gate Metal Resistance Thermometry (GMRT) are compared with the model.