A self-consistent reduced order model for current and temperature in GaN HEMTs

A physics-based reduced order self-consistent electro-thermal model is presented for AlGaN/GaN HEMT to obtain current and temperature in the device. The model uses device geometry and temperature dependent material properties as input parameters and requires minimal fitting parameters. The model has the ability to include the effects of self-heating, thermal spreading, and thermal cross-talk in a multi-finger device. The model is validated with the experimental data and physical simulations for single and multi-finger cases and provides reasonably accurate predictions for both current and temperature in the device. The model can capture the spatial variation of temperature profile across the device and therefore, can predict the finger-level variation in the drain current in a multi-finger HEMT. The model is computationally efficient, and can be used for design and analysis of GaN based devices and systems.