Analysis of sub-threshold swing and performance of various tunnel transistors

In the last few decades, MOSFET scaling has enabled smaller and faster transistors that consume less power per operation. Device dimensions are shrunk into the sub-65-nm regime, However, In order to increase the speed of operation, the sub-threshold swing has to be reduced to below 60 mV/dec. Advanced electron devices such as impact ionization FET, p-i-n and p-n-p-n tunnel FET, double gate tunnel FET, nano electromechanical FET, and FBFET have been proposed recently as novel concepts by many researches to achieve sharper swings below 60 mV/dec. As a result, these devices potentially enable reduced Vdd operation and contribute considerable reduction in system power. In this paper, detailed study of subthreshold swing is done and performances of above mentioned transistors are analyzed. In this analysis it is found that the IMOS device has least sub-threshold swing than other transistors. It was also found that FBFET has low value of loaded and unloaded delay while comparing other transistors. NEMFET and PNPN consume low active power than other transistors.