The Effect of Post-Oxide Annealing on H2O2-Grown Al2O3, AlGaN/GaN Polarization Charges and MOS-HEMT Performances

This work investigates the effect of post oxide annealing (POA) on the AlGaN/GaN MOS-HEMT with a gate oxide grown by the H2O2 oxidation technique. The experimental results suggest that the gate dielectric layer with the POA treatment improves the dielectric material quality and MOSHEMT performances. The dielectric breakdown field (EBD) of Al2O3 is improved from 6.5 to 7.9 MV/cm. In addition, the hysteresis measurement suggests that the fixed charges in Al2O3 and the interface charges (Dit) at Al2O3/AlGaN interface are reduced. This work also finds that the POA affects polarization charge density and improves MOS- HEMT performances.