2D analytical modelling of asymmetric junctionless dual material double gate MOSFET for biosensing applications considering steric hindrance issue

The current manuscript for Asymmetric Junctionless Dual Material Double Gate MOSFET (AJDMDG MOSFET) biosensor reports improved sensitivity for both threshold voltage and ON-current. In the presence of high-K dielectric material, the device was built using both neutral and charged biomolecules. After calculating the minimal surface potential, the threshold voltage is calculated by solving the 2D Poisson's equation using a parabolic-potential configuration under realistic boundary circumstances. Analytical results show good agreement with TCAD simulation, prompting an exploration of threshold voltage sensitivity with front-gate voltage changes of all possible dimensions. Corresponding drain current sensitivity with a higher ON-to-OFF current ratio is theoretically estimated and compared with identical DGFET architecture, resulting in a significant improvement for all possible step patterns when steric hinderance is considered for moderately filled cavities; this aids in detecting both labelled and label-free electrical species at lower concentration levels.

Automated summary

This manuscript introduces an Asymmetric Junctionless Dual Material Double Gate MOSFET (AJDMDG MOSFET) biosensor that exhibits improved sensitivity for both threshold voltage and ON-current. By utilizing both neutral and charged biomolecules, the device is constructed with high-K dielectric material. The threshold voltage is calculated by solving the 2D Poisson's equation and analyzing the minimal surface potential under realistic boundary circumstances, with good agreement between analytical and TCAD simulation results. The drain current sensitivity, along with a higher ON-to-OFF current ratio, is theoretically estimated and compared with identical DGFET architecture, showcasing significant improvement for various step patterns when considering steric hinderance for moderately filled cavities, enabling the detection of labeled and label-free electrical species at lower concentrations.