A new stacked gate oxide L-shaped tunnel field effect transistor

In this paper, a new stacked gate oxide L-shaped Tunnel Field Effect Transistor (LTFET) is proposed. The stacked gate oxide structure incorporates high-k and SiO₂ dielectrics. The high-k dielectric, specifically, contributes to a robust electric field at the source/channel junction. This augmented electric field results in more energy band bending and a thinner tunneling barrier. As a result, the proposed device shows the drain current of 0.224 mA/μm, OFF-current of 1.3 × 10^–17 A/μm, threshold voltage of 0.62 V and average subthreshold swing of 34 mV/decade, in comparison with the conventional LTFET. Moreover, this paper demonstrates the role of both Shockley–Read–Hall generation and trap assisted tunneling in the subthreshold swing degradation due to the existence of trap inside the silicon band gap.