Bottom-up fabrication of InAs-on-nothing MOSFET using selective area molecular beam epitaxy

In this paper we report on the fabrication and electrical characterization of InAs-on-nothing metal-oxide-semiconductor field-effect transistor composed of a suspended InAs channel and raised InAs n+ contacts. This architecture is obtained using 3D selective and localized molecular beam epitaxy on a lattice mismatched InP substrate. The suspended InAs channel and InAs n+ contacts feature a reproducible and uniform shape with well-defined 3D sidewalls. Devices with 1 μm gate length present a saturation drain current (I _Dsat) of 300 mA mm^-1 at V _DS = 0.8 V and a trans-conductance (G_M ) of 120 mS mm^-1 at V _DS = 0.5 V. In terms of electrostatic control, the devices display a minimal subthreshold swing of 110 mV dec^-1 at V _DS = 0.5 V and a small drain induced barrier lowering of 50 mV V^-1.