Effect of Pocket Intrinsic Doping on Double and Triple Gate Tunnel Field Effect Transistors

摘要

Band-to-band tunneling at the source-channel junction of multigate tunnel field effect transistors (TFETs) plays a major role to boost ON current for eliminating short channel effects (SCE). In this paper, the conventional double gate TFET structure (DG-TFET) is designed and modified by applying gate engineering to design triple gate TFET (TG-TFET). The work mainly focuses on drain current (Ion) assessment, fast switching ratio (I_(ON)/I_(OFF) and subthreshold swing (55) by comparing between conventional DG-TFET and proposed TG-TFET with pocket intrinsic layers. The variation of drain current for different pocket intrinsic doping conditions on TFET performance has been reviewed and demonstrated with SIL-VACO TCAD simulator. The pocket intrinsic triple gate TFET shows a higher Ion and better (I_(ON)/I_(OFF) ratio of 5.51 for source and pocket doping of 1 × 10~(20) cm~(_3) and 1 × 10~(15) cm~(-3). This provides 68.51 % fast switching ratio as compared to other non-conventional tunnel FETs. But the subthreshold swing (55) is limited by variation of pocket doping from 10~0 to 10~(18) cm~(_3) for TG-PI-TFET, since DG-PI-TFET provides better subthreshold swing of 23.93 mV/dec £60 mV/dec) considering the leakage current for low-power applications.