Extraction of an Electrothermal Mobility Model for AlGaN/GaN Heterostructures

An electron mobility model for AlGaN/GaN heterostructures taking both the lattice temperature and electric field into account is proposed. Numerical device simulation of an ungated Al0.25Ga0.75N/GaN HEMT structure on 4H-SiC substrate is compared to measured electrical characteristics. Mobility model parameters are extracted by comparing iso-thermal numerical simulations with microwave (6 GHz) large signal measurements. The extracted model was used in static simulations, showing good agreement with measurements