Trends and challenges in Tunnel-FETs for low power electronics

The quest for low power electronics has driven extensive research on alternative device architectures. To maintain a sufficiently large ION/IOFF current ratio, devices with a subthreshold swing (SS) below the 60mV/decade limit as for MOSFETs are needed. Tunnel-FETs (TFET) promise a SS smaller than 60mV/dec and are therefore considered as interesting candidates to replace MOSFETs for low-power applications. However, the small band-to-band-tunneling efficiency due to the large indirect bandgap of silicon results in low on-currents of all-silicon TFETs. Therefore, new materials such as III-V compounds or germanium, featuring lower bandgaps and smaller effective mass to improve the tunneling efficiency, heterogeneous integration and different TFET device architectures are discussed. 2D semiconductors materials are also investigated for possible application in TFETs.