InAlAs/InGaAs metamorphic high electron mobility transistor with a liquid phase oxidized InAlAs as gate dielectric

The In(0.52)A(10.48)As/In0.53Ga0.47As metal-oxide-semiconductor metamorphic high electron mobility transistors (MOS-MHEMTs) with a thin InAlAs native oxide layer are demonstrated. After highly selective gate recessing of InGaAs/InAlAs using citric buffer etchant, the gate dielectric is obtained directly by oxidizing InAlAs layer in a liquid phase solution near room temperature. As compared to its counterpart MHEMT, the fabricated InAlAs/InGaAs MOS-MHEMT exhibits larger gate swing voltage, higher drain-to-source breakdown voltage, and at least 1000% improvement in gate leakage current with the effectively suppressed impact ionization effect.