Tunnel Field-Effect Transistor With an L-Shaped Gate

Abstract

In this letter, a new L-shaped gate tunnel field-effect transistor (LG-TFET) is proposed and investigated by Silvaco Atlas simulation. The tunneling junction in the LG-TFET is perpendicular to the channel direction that facilitates the implementation of a relatively large tunneling junction area. The channel is U-shaped that makes the channel mainly distribute in the vertical direction, reducing the device area. The n+ pocket design is also introduced between the source and the intrinsic regions to improve the device characteristic. In addition, the gate and n+ pocket region overlap both in the vertical and the lateral directions resulting in an enhanced electric field, and the ON-state current of the LG-TFET is increased up to $\sim 50$ % compared with the previous L-shaped channel TFET. The minimum subthreshold swing of the LG-TFET is 38.5 mV/decade at 0.2 V gate-to-source voltage. By using the L-shaped gate, U-shaped channel, and the insertion of n+ pocket, the overall performance of the LG-TFET is optimized.