Single-trap phenomena stochastic switching for noise suppression in nanowire FET biosensors

With the fast-shrinking of the transistor dimensions, the low-frequency noise level considerably increases emerging as an important parameter for the design of advanced devices for information technologies. Single-trap phenomena (STP) is a promising approach for the low-frequency noise suppression technique in nanotransistor biosensors by considering trapping/detrapping noise as a signal. We show a noise reduction mechanism offered by STP in nanoscale devices making the analogy with stochastic resonance effect found in biological systems by considering a single trap as a bistable stochastically driven nonlinear system which transmits and amplifies the weak signals. The STP noise suppression effect is experimentally demonstrated for the fabricated liquid-gated nanosensors exploiting STP. We found the optimal conditions and parameters including optimized gate voltages to implement a stochastic switching effect for the extraction of useful signals from the background noise level. These results should be considered for the development of reliable and highly sensitive nanoscale biosensors. (author)