Study of PEALD-AlN as Dielectric Layer in GaN MIS-HEMTs

In this paper, the Aluminum Nitride (AlN) film was investigated based on Plasma-Enhanced Atomic Layer Deposition (PEALD) by varying process parameters (RF power, NH3 pulse time, temperature). The optimized AlN achieved a high breakdown voltage of 18 V on Si. The 10 nm AlN film is demonstrated as a dielectric layer in GaN MIS- HEMTs. The devices exhibited a threshold voltage (
$V_{\text{TH}}$
) of −4.4 V and a peak transconductance (gmax) that reached 171.3 mS/mm. Furthermore, the leakage current test results indicate that the device exhibits characteristics more aligned with Schottky contact performance.