Impact of leakage current in germanium channel based DMDG TFET using drain-gate underlap technique

In this work, a dual metal (DM) double-gate (DG) Tunnel Field Effect Transistor (DMDG-TFET) with drain-gate underlap is proposed to overcome the challenges in conventional TFET. The ON-current (Ion), OFF-current (Ioff), Ion/Ioff ratio, subthreshold swing (SS) and ambipolar current (Iambi) of the proposed device with drain underlap are investigated as gate length is scaled (LGATE) down. The proposed device gives a better suppression in leakage current and low ambipolar current. The suppressed leakage current (Ioff) and ambipolar current (Iambi) are 9.49 × 10−14 A/µm and 1.95 × 10−12 A/µm respectively for a gate length (LGATE) of 36 nm and a channel length (LCh) of 50 nm for a supply voltage of 0.5 V. Excellent switching behavior is achieved when gate length (LGATE) is 72% of the channel length (LCh). The proposed architecture is suitable for low power applications.