Monolithic integration of enhancement (E)and depletion (D)-mode metamorphic In0.52Al0.48As/In0.53Ga0.47 As/GaAs HEMTs with 0.35 μm gate-length is presented for the first time. Epilayers are grown on 3-inch SI GaAs substrates using molecular beam epitaxy. A mobility of 9550 cm2/V-s and a sheet density of 1.12 × 1012 cm-2 are achieved at room temperature. Buried Pt-gate was employed for E-mode devices to achieve a positive shift in the threshold voltage. Excellent characteristics are achieved with threshold voltage, maximum drain current, and extrinsic transconductance of 100 mV, 370 mA/mm and 660 mS/mm, respectively for E-mode devices, and -550 mV, 390 mA/mm and 510 mS/mm, respectively for D-mode devices. The unity current gain cutoff frequencies of 75 GHz for E-mode and 80 GHz for D-mode are reported.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering