2 S/mm transconductance InAs-inserted-channel modulation doped field effect transistors with a very close gate-to-channel separation of 14.5 nm

We have achieved a very small gate-to-channel separation d gi +Δ d of 14.5 nm for InAs-inserted-channel modulation doped field effect transistors (InAs-MODFETs) with the optimum control of wet-chemically recessed groove for gate electrodes. Excellent output characteristics as well as high channel current more than 1 A/mm can still be retained. The optimum wet-chemically fabricated deep recess groove leads to an absence of the influences of surface potential. Combining the Γ-gate fabrication technique, d gi +Δ d =14.5 nm produces a maximum extrinsic transconductance of 1.95 S/mm at a drain bias of 1.5 V. This is attributed to the very small gate-to-channel distance, the optimum gate fabrication technology, and the optimum channel design as well.