Performance assessment of charge plasma based hetero‐structure VTFET biosensor for linearity enhancement

Abstract

AbstractThis paper examines a charge plasma‐based hetero‐structure full gate vertical tunnel field effect transistor (CP‐FG‐VTFET) as a dielectrically modulated biosensor. It is also compared with a charge plasma‐based short gate vertical TFET (CP‐SG‐VTFET) biosensor and a charge plasma‐based asymmetrical vertical TFET (CP‐AS‐VTFET) biosensor with identical dimensions. We examine the basic physics of these biosensors and compare their ability to recognize charged and neutral molecules. It has been noted that these designs, which use GaSb as the n‐type TFET source material, are suitable for supply voltages lower than 1.2 V. The short gate device has a lower miller capacitance and a higher drive current because it has a narrow bandgap source material. Additionally, the left and right gate alignment of asymmetrical gate architectures has a considerable impact on the sensitivity of the device. Therefore, a simulation is conducted to assess the effects of gate misalignment on biosensor surface potential and drain current sensitivity. In addition, various figures of merits (FOMs) are computed for the device utilizing the dielectric constant range of 1–12, including linearity, sensitivity, and evaluation of noise characteristics. The widely available Silvaco TCAD was employed to simulate the proposed VTFET biosensors. A comprehensive evaluation of the FOM values showed that the CP‐FG‐VTFET is a promising device in terms of linearity and sensitivity.