Impact of bio-target location and their fill-in factor on the sensitivity of hetero channel double gate MOSFET label-free biosensor

Soumya S Mohanty, Sikha Mishra, Meryleen Mohapatra and G P Mishra

Abstract

In this work, the performance of dielectric modulated InP/InGaAs/InP based on the hetero channel dual material double gate MOSFET (DM-H-DMDG MOSFET) for the label-free electrical identification of bio-targets has been inspected with the help of a 2D TCAD device simulator. The impact of bio-target's location and their fill factor position has been analysed to observe the device sensitivity. Under the dry situation, the effect of charged and non-charged biomolecules on the electrical features such as threshold voltage, electric field, drain current, subthreshold performance, and sensitivity of DM-H-DMDG MOSFET has been evaluated. Simulation results show that the threshold voltage sensitivity of the proposed device is 0.62 and 0.59 when the fill factor is 100% and 50% respectively. The peak value of an electric field is 4.2 × 10⁶ V cm⁻¹ and 4.5 × 10⁶ V cm⁻¹ respectively near the source end and 0.5 × 10⁵ V cm⁻¹ and 5.5 × 10⁵ V cm⁻¹ near the drain end, when positively/negatively charged biomolecules are immobilised in the cavity. Again, the threshold voltage of the device is obtained as 0.265 V/0.245 V when the fill factor is 100% and 50% respectively.