Capacitance modeling of gate material engineered cylindrical/surrounded gate MOSFETs for sensor applications. (December 2015) - Verma, Jay Hind Kumar
Abstract: This paper presents charge based analytical drain current and capacitance model of material engineered Cylindrical/Surrounded Gate (CGT/SGT) MOSFET with nanogap cavity region for sensor applications. Material engineered i.e. dual material gate provides improvement in Short Channel Effects (SCEs) and cylindrical shape nanogap cavity region is used for sensing of biomolecule strength. The material engineered CGT/SGT MOSFET sensor electrically detect the targeted biomolecules of different strength by change in drain current and gate capacitance. Analysis has been carried out by using unified charge control based model derived from Poisson's equation. It is shown that sensitivity of changing biomolecules strength is more in gate capacitance than the drain current. The results so obtained are in good agreement with the 3D simulated data which validate the model. Highlights: Capacitance modeling of Gate Material engineered CGT/SGT has been done. We developed material engineered CGT/SGT MOSFET as a sensor for determining bio-molecule strength. Gate cavity over a thin silicon layer oxide layer is used for targeted bio-molecule detection. Changing bio-molecule strength in the gate cavity is evaluated by drain current and gate capacitance. Evaluation of sensing ability by Gate capacitance is better than the sensing ability of drain current.