Demonstration of a novel tunnel FET with channel sandwiched by drain

Abstract

A novel double gate tunnel FET with channel sandwiched by drain (CSD-TFET) is proposed and investigated in this paper. The proposed CSD-TFET consists of three differently doped drain layers in which the middle layer is an extension of the channel and is sandwiched by the heavily doped top and bottom drain layers. The objective of the proposed endeavor is to reduce the ambipolar current without affecting the ON current. We have compared the results of CSD-TFET with the reference tunnel FET (RTFET) designed by using the same simulation setup as opted for simulating the proposed CSD-TFET. The extracted ambipolar current of CSD-TFET is ∼104 times lower than that of RTEFT with no change in the ON current. An interesting flipping/crossover phenomenon in the gate-to-drain capacitance (Cgd) of the proposed CSD-TFET at a certain gate-to-drain voltage (VGD) is observed. We also discussed the saturation phenomenon of the drain current and the variation of unity gain frequency with Cgd © 2019 IOP Publishing Ltd.