Investigation the impact of the gate work-function and biases on the sensing metrics of TFET based biosensors

Abstract

In this work, we examined the impact of gate work-function and back-gate bias to enhance sensing metrics of a Dielectric Modulated (DM) p-type Tunnel Field Effect Transistor (p-TFET) based biosensor. The sensing metrics, namely Sensitivity (S) and Selectivity (ΔS) are considerably improved by using a lower value of gate work-function and positive back gate voltages. It is shown that by appropriate selection of gate work-function and back gate bias, Band-to-Band Tunneling (BTBT) of carriers is reduced and a significant change in electrical characteristics is observed in a device with an empty cavity. Therefore, the relative change in the drain current due to the presence of biomolecules in the nanogap cavity is maximized. Results indicate a Sensitivity of ∼10 9 for 3-aminopropyltriethoxysilane (APTES) biomolecule, and Selectivity of ∼10 2 for APTES concerning Biotin biomolecule in an optimally designed p-TFET biosensor. The impact of location, as well as the charge of biomolecules, are also analyzed in this work. Results showcase the additional degree of freedom through device optimization which facilitates the tunability of sensing metrics for improved biosensor performance.

Sensitivity Analysis of Biosensors Based on a Dielectric-Modulated L-Shaped Gate Field-Effect Transistor

“…In Figure 9 a,b, we show the comparison of the DM-LTFET metrics with previously published papers. It can be clearly seen from Figure 9 a that, compared with previously published papers [ 16 , 17 , 18 , 20 , 26 ] (which have double gates), the DM-LTFET could simultaneously have a larger on-state current and I on / I off sensitivity. At the same time, it can be obviously seen from Figure 9 b that the current sensitivity and sub-threshold swing sensitivity of the proposed structure were higher than those of the past published papers [ 16 , 18 , 19 , 20 ].…”

“…Due to its low cost and easy operation, dielectric modulation is applied in biosensors [ 11 , 12 , 13 , 14 ]. Therefore, sensors made using dielectric modulation based on a TFET have been studied by many scholars [ 15 , 16 , 17 , 18 ]. In 2016, Kanungo et al studied the influence of silicon germanium (SiGe) sources and n+-pocket-doped channels on dielectric modulation sensors.…”

Dielectric-Modulated Double Gate Bilayer Electrode Organic Thin Film Transistor-based Biosensor for Label-Free Detection: Simulation Study and Sensitivity Analysis

“…FETs were also recently utilized to diagnose the highly contagious COVID-19 illness due to the corona virus [4]. Various research groups [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16] have reported on the development of dielctrically modulated FET-based biosensors. Biosensors produced using FETs may be fabricated using either inorganic or organic semiconducting materials [17], [18].…”

Gate-on-Drain Overlapped L-Shaped Channel Tunnel FET as Label-Free Biosensor

“…Tunnel FET (TFET) is one of the emerging devices which overwriting the conventional MOSFET as a biosensor due to its band to band tunneling mechanism. It is overcoming the issue of sub-60 mV/decade subthreshold swing for MOSFET at room temperature and also TFET emerging as a promising candidate for various sensing application [11][12][13][14][15][16]. Dielectric modulated TFET with various structures [6][7][8][9][11][12][13][14][15][16] have been reported since last decades which is able to produce higher sensitivity.…”

“…It is overcoming the issue of sub-60 mV/decade subthreshold swing for MOSFET at room temperature and also TFET emerging as a promising candidate for various sensing application [11][12][13][14][15][16]. Dielectric modulated TFET with various structures [6][7][8][9][11][12][13][14][15][16] have been reported since last decades which is able to produce higher sensitivity. The higher sensitivity in biosensors means Fig.…”