InAs-GaSb/Si heterojunction tunnel MOSFETs: An alternative to TFETs as energy-efficient switches?

Double-gate ultra-thin-body (DGUTB) InAs-GaSb and InAs-Si gate-all-around nanowire (GAANW) tunnel MOS-FETs (TMOSFETs) with realistic dimensions are investigated in this paper. The former with an atomistic and full-band quantum transport solver based on the sp³s* tight-binding model, the latter with an effective mass approximation mode-space non-equilibrium Green´s function tool. In the InAs-Si GAANW TMOSFETs, band-to-band tunneling is computed in a post-processing step using a rigorous analytical model that accounts for quantization effects. It is found that thicker devices are more promising regarding the ON-state current and low sub-threshold swing, e.g. I_on = 520μA/μm and SS_av = 37.5 mV/dec for a InAs-GaSb DGUTB TMOSFET with thickness of 4 nm.