AlGaN/AlN/GaN MOS-HEMTs with Al2O3 gate dielectric formed by using ozone water oxidation technique

This work presents Al
_0.3
Ga
_0.7
N/AlN/GaN metal-oxide-semiconductor high electron mobility transistors (MOS-HEMTs), grown on the Si substrate, with high-k Al
₂
O
₃
gate dielectric. The present AlGaN/AlN/GaN MOS-HEMT design (the control Schottky-gate HEMT) has showed two-terminal gate-drain breakdown voltage (BV
_GD
)/turn-on voltage (V
_on
) of -146.6/1.12 (-96.4/0.98) V, maximum extrinsic transconductance (g
_{m, max}
) of 167.3 (124.2) mS/mm, saturated I
_DS
density at V
_GS
= 0 V (I
_DSS0
) of 701.4 (538.2) mA/mm, maximum I
_DS
density (I
_{DS, max}
) of 927.9 (646) mA/mm, A
_V
of 211.8 (172.5), unity-gain cut-off frequency (f
_T
) of 16.8 (11) GHz, maximum oscillation frequency (f
_max
) of 18.8 (14) GHz, 2.4-GHz output power (P
_out
) of 17.2 (15.7) dBm, power gain (G
_S
) of 14.1 (13.4) dB, and power-added efficiency (PAE) of 32.2% (27.4%). Consequently, superior improvements of 52.2% in BV
_GD
, 43.6% in I
_{DS, max}
, 34.7% g
_{m, max}
, and 52.7%/34.3% in f
_T
/f
_max
are achieved as compared with a control HEMT device.