Thermal and trapping phenomena assessment on AlGaN/GaN microwave power transistor

In this paper a systematic analysis of thermal and trapping behaviour of microwave power AlGaN/GaN HEMTs has been carried out through pulsed current-voltage (PIV) measurements and S parameters. It is shown that the thermal resistance of the device can be accurately determined provided that some assumptions on the trapping behaviour of the device are verified. The values obtained have been checked by three dimensional finite element (3D-FE) simulations with reasonable accuracy. Kink effects in the output characteristics have been analysed at different temperatures and it has been shown that they are more pronounced at ambient temperature. Finally the microwave behaviour of the device versus temperature has been assessed.