ABSTRACT Tunnel field‐effect transistors (TFETs) are promising for ultra‐low‐power electronics, yet their practical adoption is hindered by limited ON‐current and strong sensitivity of band‐to‐band tunneling (BTBT) to geometry, doping, and quantum confinement, making physics‐accurate design optimization essential. In this paper, we present a comprehensive study on the design of a p + –n + InAs‐based TFET. InAs is selected for its narrow bandgap and low carrier effective mass, which enhances BTBT and enables steep switching at reduced supply voltages. The proposed homojunction architecture comprises three regions with only two different doping levels: a highly doped p + source and an n + ‐doped channel and drain. We systematically optimize the source and channel/drain doping concentrations and the source length using a composite figure of merit (FOM) that consolidates key digital and RF metrics, including , subthreshold swing (SS), threshold voltage ( V t ), and maximum cut‐off frequency ( f Tmax ). The FOM‐optimized design achieves a wide switching window with SS ≈ 18 mV/dec while improving the RF performance toward ≈ 30 GHz, and it outperforms a conventional aligned‐gate p–i–n InAs TFET. Finally, we assess practical oxide/InAs interface nonidealities and show that the optimized device retains acceptable robustness over the explored trap‐charge range.
Elgamal et al. (Sun,) studied this question.