Passivation of InGaAs/InAlAs/InP HEMTs using Al2O3 atomic layer deposition

InGaAs/InAlAs/InP HEMTs (InP HEMTs) passivated by Al
₂
O
₃
atomic layer deposition (ALD) demonstrated improved DC performance compared to Si
₃
N
₄
plasma enhanced chemical vapour deposition (PECVD). DC measurements have been performed on 130 nm gate-length devices before and after passivation. An increase in maximum drain current density of 20% and extrinsic transconductance of 30% were observed after both ALD and PECVD device passivation. In comparison to PECVD passivated InP HEMTs, ALD passivated devices demonstrated a full suppression of a kink in the I-V characteristics associated with surface traps.