Towards high buffer breakdown field and high temperature stability AlGaN channel HEMTs on silicon substrate

The rapidly increasing power demand, downsizing of power electronics and material specific performance limitation of silicon have led to the development of AlGaN/GaN heterostructures for high power applications. In this frame, emerging Al
x
Ga
1-x
N channel based heterostructures show promising features for the next generation of power electronics. In this work, we propose the study of breakdown field variation through the AlGaN channel HEMTs-on-Silicon with various Al composition. The fabricated devices exhibited remarkable buffer breakdown electric field > 2.5 MV/cm for sub-micron heterostructures grown on silicon substrate. Furthermore, we also experimentally demonstrate that Al-rich AlGaN channel enables both boosting the 3-terminal transistor breakdown voltage and benefiting from superior thermal stability.