Vertical Tunneling Based Dual-material Double-gate TFET

Abstract

To enhance current driving capability, switching ratio and subthreshold swing, a novel device structure vertical tunneling based dual-material double-gate tunnel field-effect transistor (VTDMDG-TFET) is designed in presented work. The device optimization of proposed device in terms of work-function engineering, gate oxide material, gate length, output characteristics and Si-thickness is done by the authors. Moreover, dual-gate approach is used in this work for enhancement in ON-state current of VTDMDG-TFET. Further, gate terminal of VTDMDG-TFET is comprised of two metal gates, namely auxiliary gate and tunnel gate. Use of dual-material at gate terminal makes the presented device structure adequate in terms of high ON-current, optimized subthreshold-swing as well as high switching ratio. To get the better electrostatic control of the gate higher dielectric constant material HfO2 is used as the gate dielectric material oxide, which enhances the ON-current of the presented structure. VTDMDG-TFET is also found better in terms of improved transconductance. The improved transconductance of the device makes VTDMDG-TFET a better choice for analog/RF and linearity performances. This leads to the TFET applications in the field of energy harvesting, biosensing, ultra-low power RF circuits.