InGaP/InGaAs MOS-PHEMT with a nanoscale liquid phase-oxidized InGaP dielectric

InGaP/InGaAs metal–oxide–semiconductor (MOS) pseudomorphic high-electron-mobility transistor (PHEMT) with a nanoscale liquid phase-oxidized InGaP as the gate dielectric is demonstrated. Not only does the MOS-PHEMT have the advantages of the MOS structure, but it also has high-carrier density and a high-mobility 2DEG channel. Using selective oxidation of InGaP by liquid phase oxidation, the MOS-PHEMT can be fabricated without additional recess processes. The MOS-PHEMT exhibits larger transconductance, lower gate leakage current, higher breakdown voltage, higher cut-off frequency, lower minimum noise figure, and higher power-added efficiency than does its counterpart (reference PHEMT). The interface roughness effect on the DC and RF performance of devices is also discussed.

► This paper exhibits the possibility of InGaP/InGaAs MOS-PHEMT with LPO.
► With the help of the LPO, the threshold voltage can be shifted positively.
► The results also show better dc, microwave, noise, and power performances.
► The LPO does not degrade the device surface roughness characteristic.