InSb Source-Based Heterojunctionless Nanowire Tunneling FET for Biosensing Application: Design and Analysis

In this paper, we introduce a novel biosensor leveraging an InSb-source-based heterojunctionless nanowire TFET design tailored for biosensing applications. The incorporation of a low-bandgap InSb source enhances both drain current and sensitivity in our proposed biosensor. The unique feature of a hetero-but junctionless configuration eliminates the need for a physical metallurgical junction, presenting a fabrication process that is not only cost-effective but also streamlined, avoiding high thermal budgets and also eliminating the issue of random dopant fluctuations (RDF). Furthermore, unlike conventional homojunction-based TFET biosensors, where increased biomolecule permittivity reduces threshold voltage while elevating drain current, our proposed biosensor, featuring a III-V nanowire design, demonstrates intriguing behavior. With rising k-values, the ON current increases; however, concurrently, the threshold voltage also rises compared to conventional TFET biosensors. This unique behavior results in a simultaneous enhancement of ON current and reduction in OFF current, attributed to the increased threshold voltage. Consequently, the I <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</inf> /I <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">OFF</inf> ratio and sensitivity experience improvements, presenting promising outcomes for the proposed biosensor.