Modeling simulation and analysis of double gate mosfet structures for biosensing applications

Abstract

Label free and real time recognition of ions and charged molecules have been accomplished with the Field Effect Transistors FETs based devices Bergveld 1972 has reported a first Ion Sensitive FETs ISFETs In ISFETs biomolecules land on the insulator region through an aqueous solution The feature of ion and its concentration have caused a noticeable change in the response of the ISFETs Subsequently Silicon Metal Oxide Semiconductor FET MOSFET based biosensors have been developed to detect the bio chemical species Two types of biomolecules are discussed namely fixed charge biomolecules and neutral biomolecules The biomolecules are characterized with fixed positive negative charge densities and different dielectric constant values The biomolecules are assumed to be immobilized on the top surface of the oxide region As a result of this a measurable change in the electrical characteristics of the biosensors has been reported This rate of change has been considered as a sensing metric of MOSFET based biosensors Many types of FETs have been developed for detecting bacteria protein and ions They are not limited to Silicon MOSFETs They are also fabricated with nanomaterials like Graphene and Carbon nanotubes due to their biocompatibility Also the next generation MOSFET biosensors will be designed for the ultra sensitive detection with Molybdenum Disulfide MoS2 layers Since the Lab on a chip technology is aiming for a portable or handheld devices for the synthesis and analysis process of biochemical species and MOSFETs have the advantage of being able to be highly integrated on a single chip MOSFET based biosensors have been investigated as the promising candidate in the biosensor fabrication Since MOSFETs are shrinking to reach Giga Scale Integration GSI Quantum Mechanical Effects QMEs need to be considered in MOSFET design and modeling newline