Impact of source doping on the performance of vertical InAs/InGaAsSb/GaSb nanowire tunneling field-effect transistors

In this paper, we analyze experimental data from state-of-the-art vertical InAs/InGaAsSb/GaSb nanowire tunneling field-effect transistors (TFETs) to study the influence of source doping on their performance. Overall, the doping level impacts both the off-state and on-state performance of these devices. Separation of the doping from the heterostructure improved the subthreshold swing of the devices. The best devices reached a point subthreshold swing of 30 mV/dec at 100 x higher currents than previous Si-based TFETs. However, separation of doping from the heterostructure had a significant impact on the on-state performance of these devices due to effects related to source depletion. An increase in the doping level helped to improve the on-state performance, which also increased the subthreshold swing. Thus, further optimization of doping incorporation with the heterostructure will help to improve vertical InAs/InGaAsSb/GaSb nanowire TFETs.