Improving performance of Al2O3/AlN/GaN MOSC-HEMTs via microwave annealing

A multi-functional microwave annealing (MWA) process was proposed for high-performance GaN heterostructure devices. By this means, an Al2O3/AlN/GaN MOS-channel high-electron-mobility transistor was fabricated. The MWA was performed on both the AlN insertion layer and electrode metals, enabling the formation of high-quality AlN/GaN interface and good ohmic contact at the same time. A better performance of lower threshold voltage hysteresis (more than 2 times lower), smaller gate leakage, and larger current output (∼1.7 times larger) was hence obtained.