AlGaN/GaN HEMT channel temperature determination utilizing external heater

An improved method of average channel temperature and channel temperature profile determination is introduced in this paper applied to AlGaN/GaN HEMT using quasi-static I-V characterization and external heater. Particular HEMT resistances and threshold voltage were experimentally determined at different ambient temperatures from TLM measurements, HEMT output and transfer I-V characteristics. Negligible pinch-off area and leakage current dependence on drain voltage allows to obtain average temperature similar to 77 degrees C for dissipated power 1.5W using simple recurrent differential calculations. The HEMT channel temperature profile exhibiting maximum peripheral temperature similar to 130 degrees C for dissipated power 1.5W was simulated and verified utilizing the device electrical parameters variation.