Optically Controlled Nanoscale FET Toward Advanced Biosensing Applications

Sensitivity enhancement is an important aspect of the development of ultrasensitive biosensors. Single-trap phenomena observed in liquid-gated nanostructures provide a new opportunity to enhance the sensitivity of nanoscale biosensors. The impact of light excitation on properties of a unique nanowire (NW) field-effect transistor (FET) structures utilizing single trap phenomena are studied. We revealed that parameters of single trap and interface phenomena in NW FET can be effectively tuned in a controlled way using optical excitation. Under the influence of optical radiation, the population of discrete levels is redistributed, which allows to control of their energy characteristics and, as a result, establishes the optimal sensitive regimes. A model of the potential profile description for carriers in NW structure is discussed to describe the mechanisms of capture dynamics in fabricated NW FETs and to control sensitivity in advanced biosensors.