2D tunnel transistors for ultra-low power applications: Promises and challenges

Tunnel field-effect (TFET) transistors [1] are among the most promising devices for future low-power electronics [2]. However, TFETs usually suffer from low ON-current values. Recently, it has been shown that TFETs made from 2D materials, can in principle, provide high ON-currents due to their tight gate control [3]. A better gate control over the channel increases the electric field at the tunnel junction, which results in a higher performance [3, 8]. 2D TFETs are known as steep subthreshold swing (SS) devices with the goal of lowering VDD. However, in the previous atomistic simulations of transition metal dichalcogenide (TMD) TFETs a VDD of 0.5V has been used [3] which is still a high value for ultra-low power applications. In this work, the performance of ultra-low power WTe2 TFETs with a VDD of 0.25V is studied. Comparing the performances of WTe2 TFETs with VDD of 0.25V and 0.5V exhibits the promises and the challenges ahead of lowering VDD in the ultra-low power TFETs.