Analytical model for the threshold voltage of III–V nanowire transistors including quantum effects

•An analytical model for the threshold voltage of III–V cylindrical NWs is proposed.•The model accounts for 2D quantum confinement with non-parabolic corrections.•The calculated VT is valid for different materials, NW sizes and oxide thicknesses.•This work gives insight in the different contributions to the threshold voltage.

In this work we propose an analytical model for the threshold voltage (VT)(VT) of III–V cylindrical nanowires, that takes into consideration the two dimensional quantum confinement of the carriers, the Fermi–Dirac statistics, the wave-function penetration into the gate insulator and the non-parabolicity of the conduction band structure. A simple expression for VTVT is obtained assuming some suitable approximations. The model results are compared to those of a 2D self consistent Schrödinger–Poisson solver, demonstrating a good fit for different III–V materials, insulator thicknesses and nanowire sizes with diameter down to 5 nm. The VTVT dependence on the confinement effective mass is discussed. The different contributions to VTVT are analyzed showing significant variations among different III–V materials.