Characteristics of TiO2 thin film with back-gate biasing for FET-based biosensors application

Biosensors become a main attraction nowadays due to its importance towards human health. Its allow rapid and label-free detection that provides low cost clinical sampling. A FET device was fabricated from silicon-on-insulator (SOI) type of wafer with titanium dioxide (TiO₂) thin film as a sensing medium. TiO₂ was deposited by using sol-gel solution, spin coated on the device, patterned and anneal. The physical characterization by using AFM and XRD was conducted to confirm the thin film was a TiO₂ and electrical characterization was to determine the electrical properties, stability and sensitivity of the devices. From the result AFM and XRD confirm the thin layer was a TiO₂ layer with grain boundaries and several peaks of TiO₂ anatase crystal structure. The current-voltage (I-V and Vbg-Id) show that the TiO₂ thin film has a good electrical properties and sensitivity that very suitable in sensing application especially detecting biomolecules for disease detection.