2-D Analytical Modeling and Simulation of Dual Material, Double Gate, Gate Stack Engineered, Junctionless MOSFET based Biosensor with Enhanced Sensitivity

In this work, a 2 - D analytical model of Dielectrically Modulated, Dual Material, Double Gate Junctionless MOSFET (DMDG-JL-MOSFET) based label free biosensor has been proposed to investigate the effect of high-kappa gate dielectric materials (TiO2, HfO2, and Al2O3) and cavity length variation on the sensitivity of the biosensor. The model has been validated with data obtained from Sentaurus TCAD simulator. The variation in threshold voltage (V-th), drain current (I-d) and I-ON/I-OFF ratio has been used as the sensing metric to estimate the sensitivity of the proposed biosensor. It has been observed that at a cavity length (L-cav) of 25 nm, TiO2 shows 87%, 68% and 52% higher sensitivity than if SiO2 is taken as gate dielectric in case of neutral, positively charged and negatively charged biomolecules respectively. Further, the effectiveness of the proposed DMDG-JL-MOSFET based biosensor is confirmed by benchmarking the sensitivity metric with contemporary architectures of JL-MOSFET based biosensor. We have reported that DMDG-JL-MOSFET exhibits significant increase in sensitivity when compared to other contemporary JL-MOSFET based biosensors, thus making the proposed device an attractive solution for biosensing applications.