A Novel Approach Dual Material Double Gate Germanium-Based TFET

Abstract

Modeling and design are carried out of an n-type dual material double gate Tunnel Field Effect Transistor (DMDGTFET) using Ge as a channel material for optimization of the low power device performance parameters like subthershold swing, total gate delay, power dissipation and (On–Off) current ratio, respectively. The energy band diagram, surface potential, and electric field are obtained for on state and off state of the device by the solution of 2D Poisson’s equation utilizing indigenously developed software. The results show that both on current, and (On–Off) current ratio are higher in TFET with Ge than Si as a channel material. In this paper, authors analytically and numerically solved 2D Poisson’s equation for the optimization of low power device performance parameters by changing the channel length from 20 to 30 nm and gate oxide thickness from 2 to 5 nm, respectively. The device performance parameters such as subthershold swing, (On–Off) current ratio, total gate delay, and power dissipation are found 15 mV/decade, 2.190 × 106, 7.8 ps and 2.44 fW at channel length 20 nm and gate oxide thickness 2 nm, respectively. Thus, dual material double gate germanium-based TFETs are promising next generation devices for ultra large scale integration as well as low power digital system.