A Novel n+ Pocket Doped L-Shaped Channel TFET for Biosensing Applications

This paper presents a novel channel-engineered Tunnel Field-Effect Transistor (TFET) featuring n+ pocket doping, specifically tailored for biosensing applications. The proposed TFET incorporates an L-shaped silicon (Si) channel with a distinctive configuration—an upright drain at the top and a lateral source at the bottom. Additionally, pocket doping is introduced at the source-channel interface, and a nano gate cavity under the dual gate for biomolecule immobilisation. The combination of pocket doping and the L-shaped channel significantly improves the performance of the TFET for biosensing. The device’s performance in presence of different neutral as well as charged biomolecules has been analysed using energy band variation, surface potential, internal electric field, and transfer characteristics. The device’s sensitivity and selectivity have been investigated in terms of I ON , I ON /I OFF , threshold voltage (V th ), and subthreshold swing (SS) and the proposed device’s performance has been compared with state-of-the-art biosensors.