The operating mechanism of Schottky-gate nanosensors

The highly sensitive nanowire-based Schottky-gate nanosensors for detecting UV, bio-molecules, and gas sensing were demonstrated. The operating mechanism of the Schottky-gate nanosensors is totally distinct from the conventional Ohmic contacted nanosensors. The Schottky-gated device (SGD) has a few merits in comparison to the conventional Ohmic contacted device (OCD). First, it needs no bio-probe to detect molecules; rather, it depends on the absorption of the charged molecules to the junction region. Second, as for the same type of nanowires, such as ZnO, the sensitivity of the SGD is much higher than that of OCD, because a few molecules at the junction region can change the “gate” that effectively tunes the conductance. This Schottky-gate-modulation based sensing principle can be applied to other materials and sensing systems.