Investigation of Ambipolar Conduction and RF Stability Performance in Novel Germanium Source Dual Halo Dual Dielectric Triple Material Surrounding Gate TFET

Abstract

In this study, we present an ambipolar conduction and RF stability performance for a Germanium Source Dual Halo Dual Dielectric Triple Material Surrounding Gate Tunnel FET (Ge(SRC)-DH-DD-TM-SG-TFET). The energy band diagram of the device will be derived using the Stern Stability Factor. The minimum tunneling length is expressed using low-k Silicon dioxide (SiO2) and high-k Hafnium oxide (HfO2) as dual dielectric material. Then the band to band tunneling (BTBT) rate tunneling generation rate will be derived using Kane’s model. In terms of frequency efficiency the proposed device with SiO2/HfO2 as gate dielectric is good enough to attain high cut-off frequency (fT) of 94.22 GHz is observed at drain to source voltage of VDS = 1 V. Efforts have also been made to properly assess the potential of the two halo doped regions regions. An expression for transconductance is proposed and the model is validated using 3-D Silvaco Atlas TCAD device simulator. In addition, to demonstrate the advantage of using Ge(SRC)-DH-DD-TM-SG-TFET dual dielectric halo doping in circuit applications, the transient response of the conventional TFET germanium source is compared with the low and high-k dielectric halo doping Ge(SRC) TFET.