Enhancement-mode buried-channel In0.7Ga0.3As/In0.52Al0.48As MOSFETs with high-kappa gate dielectrics

The operation of long- and short-channel enhancement-mode In 0.7 Ga 0.3 As-channel MOSFETs with high-κ gate dielectrics are demonstrated for the first time. The devices utilize an undoped buried-channel design. For a gate length of 5 μm, the long-channel devices have V t = +0.25 V, a subthreshold slope of 150 mV/dec, an equivalent oxide thickness of 4.4+/-0.3 nm, and a peak effective mobility of 1100 cm 2 /V ·s. For a gate length of 260 nm, the short-channel devices have V t = +0.5 V and a subthreshold slope of 200 mV/dec. Compared with Schottky-gated high-electron-mobility transistor devices, both long- and short-channel MOSFETs have two to four orders of magnitude lower gate leakage.