In this paper, analysis and optimization of surrounding channel nanowire (SCNW) tunnel field-effect transistor (TFET) has been discussed with the help of technology computer-aided design (TCAD) simulation. The SCNW TFET features an ultra-thin tunnel layer at source sidewall and shows a high on-current (ION). In spite of the high electrical performance, the SCNW TFET suffers from hump effect which deteriorates subthreshold swing (S). In order to solve the issue, an origin of hump effect is analyzed firstly. Based on the simulation, the transfer curve in SCNW TFET is decoupled into vertical- and lateral-BTBTs. In addition, the lateral-BTBT causes the hump effect due to low turn-on voltage (VON) and low ION. Therefore, the device design parameter is optimized to suppress the hump effect by adjusting thickness of the ultra-thin tunnel layer. Finally, we compared the electrical properties of the planar, nanowire and SCNW TFET. As a result, the optimized SCNW TFET shows better electrical performance compared with other TFETs.

In this manuscript, channel area fluctuation (CAF) effects on turn-on voltage (Von) and subthreshold swing (SS) in gate-all-around (GAA) nanowire (NW) tunnel field-effect transistor (TFET) with multi-bridge-channel (MBC) have been investigated for the first time. These variations occur because oblique etching slope makes various elliptical-shaped channels in MBC-TFET. Since TFET is promising candidates to succeed metal-oxide-semiconductor FETs (MOSFET), these variation effects have been compared to MOSFET. Furthermore, Ge homojunction TFET, one of the solutions to increase on-state current in TFET and improve SS also has been simulated using technology computer-aided design (TCAD) simulation. The results would be worth reference for future study about GAA NW TFETs.