Performance enhancement of GaN high electron-mobility transistors with atomic layer deposition Al2O3 passivation

We report a new passivation technology based on atomic layer deposition (ALD) aluminum oxide for the GaN high electron-mobility transistor (HEMT). This new process markedly enhances GaN device's electrical performance including DC, and in particular the pulsed-IV characteristics. The achieved improvement is attributed to the outstanding interface between III-N and the ALD aluminum oxide resulting from the unique process of the ALD growth, featuring a wet-chemical-based wafer preparation as well as the self-cleaning at the very beginning of the whole growth process.