Modeling GaN-HEMT Electrostatic Band Diagram under full depletion approximation

In this work, we propose a new approach to derive the GaN-HEMT energy band diagram under full depletion conditions. The model considers the vertical electric field and vertical potential within the GaN-HEMT from gate to bulk. The effect of polarized ions due to piezoelectric and spontaneous polarization is also considered. The spike-shaped electric field within the 2D electron gas predicted by the model follows TCAD simulation results. The model is validated by TCAD and by EPFL HEMT model under the depletion condition.