Bio-FET Operation and Fabrication:
– Bio-FETs operate by combining a transistor device with a bio-sensitive layer to detect bio-molecules.
– The system consists of a field-effect transistor separated by an insulator layer from the biological recognition element.
– Analyte binding alters the charge distribution affecting current flow, enabling detection.
– Fabrication involves finding a suitable substrate, applying a sensing film layer, and adding a receptor for ion detection.
– Thin dielectric layers and etch processes are used to expose the FET’s active site.
Bio-FET Advantages and Applications:
– Bio-FETs amplify small electrostatic potential changes to large current changes without extra circuitry.
– They find applications in medical diagnostics, biological research, and environmental protection.
– Bio-FETs are cost-effective, compact, and compatible with large-scale circuitry.
– They integrate easily into Lab-on-a-chip devices for real-time monitoring.
– Offer label-free detection and enhanced sensitivity in some configurations.
Bio-FET Optimization and Development History:
– Gate voltage choice influences carrier concentration and device response.
– Operating in the subthreshold region yields exponential current increase for surface potential changes.
– Various optimization techniques are discussed in the literature.
– The MOSFET was invented in 1959, with the first BioFET created in 1970.
– BioFETs have evolved from early versions like ADFET to newer types such as DNAFET and GenFET.
Bio-FET Research and Impact:
– Studies explore sensitivity enhancement of nanowire FET biosensors.
– Research on label-free DNA hybridization detection with BioFETs is ongoing.
– BioFETs have a wide range of biomedical applications and contribute to biosensing technology advancements.
– Sensitivity enhancement is crucial for accurate detection in various applications.
– Continued research drives innovation in biosensor technology.
Bio-FET Challenges and Future Prospects:
– Current challenges include stability issues, standardization of protocols, and interference from complex samples.
– Future directions involve exploring new materials and structures for BioFETs.
– MoS2 field-effect transistors show promise for next-generation label-free biosensors.
– Wearable biosensors, point-of-care devices, and precision medicine applications are potential future prospects.
– Integration with the Internet of Things (IoT) and enhanced data analytics are areas of interest for Bio-FET advancement.
A field-effect transistor-based biosensor, also known as a biosensor field-effect transistor (Bio-FET or BioFET), field-effect biosensor (FEB), or biosensor MOSFET, is a field-effect transistor (based on the MOSFET structure) that is gated by changes in the surface potential induced by the binding of molecules. When charged molecules, such as biomolecules, bind to the FET gate, which is usually a dielectric material, they can change the charge distribution of the underlying semiconductor material resulting in a change in conductance of the FET channel. A Bio-FET consists of two main compartments: one is the biological recognition element and the other is the field-effect transistor. The BioFET structure is largely based on the ion-sensitive field-effect transistor (ISFET), a type of metal–oxide–semiconductor field-effect transistor (MOSFET) where the metal gate is replaced by an ion-sensitive membrane, electrolyte solution, and reference electrode.
