Fringe-fields-modulated double-gate tunnel-FET biosensor

Abstract

This paper aims to evaluate a groundbreaking bio-TFET that utilizes the fringe fields capacitance concept to detect neutral and charged biomolecules. While facilitating fabrication process and scalability, this innovative bio-TFET is able to rival the conventional bio-TFET which relies on carving cavities in the gate oxide. The cavities of the proposed device are carved in the spacers over the source region and in the vicinity of the gate metal. Inserting biomolecules in the cavities of our bio-TFET modifies the fringe fields arising out of the gate metal. As a result, these spacers modulate tunneling barrier width at the source-channel tunneling junction. We have assessed our proposed device’s DC/RF performance using the calibrated Silvaco ATLAS device simulator. For further evaluation of the reliability of our bio-TFET, non-idealities, such as trap-assisted tunneling and temperature, are also studied. The device we propose is highly suitable for biosensing applications, as evidenced by the parameters of $${S}_{{I}_{ds}}$$ S I ds = 1.21 × 103, SSS = 0.365, and $${S}_{{f}_{T}}$$ S f T = 1.63 × 103 at VGS = 1 V.