Investigation On Device Structure Optimization And Design Of Tunneling Field Effect Transistor

With the feature size of advanced integrated circuit manufacturing reduced to less than10 nm,the development of further continuation of Moore's law has entered a bottleneck.In order to ensure the sustainable development of the performance and integration of integrated circuit,researchers have focused on tunneling field effect transistor(TFET).With its unique working mechanism of carrier band to band tunneling,TFET device is expected to obtain quite good subthreshold swing,temperature characteristics,switching current ratio and other characteristics.It is a very advantageous alternative device to realize ultra-low power chip in the future.Based on the simulation analysis of the working mechanism of PIN double gate TFET,the effects of doping concentration,spacer material properties and structural parameters on the electrical characteristics of TFET devices are analyzed,and the structural improvements of extended source(ES)and low doped drain(LDD)are proposed to increase the tunneling probability and optimize the offstate current of the device.The simulation results show that,compared with the basic PIN TFET,the proposed optimized structure TFET in this paper increases the onstate current by 24 times,the switching current ratio by 44 times,and the subthreshold swing is reduced by 26.7%.This paper made further studies on the junctionless DG-TFET and discusses the effects of gate oxide thickness and polar gate and control gate work function on the electrical characteristics of JL-TFET devices.In this paper,Ge and Si Ge materials are used to optimize the switching current ratio of the device.The simulation results show that compared with Si based JL-DGTFET device,the switching current ratio of the device designed in this paper is increased by 4.06 times,the average subthreshold swing is reduced by about 17.1%.The device performance is significantly improved.