An ambipolar field-effect transistor (FET) based on tetracyanoquarterthienoquinoid (TCT4Q) was constructed. When a set of source, drain, and gate voltages were applied to a thin film of TCT4Q at temperatures lower than 150 K, both positive and negative carriers were trapped and frozen even after removal of the gate voltage. The frozen carriers worked as a floating gate with the gradient by creating a PN(NP) junction through the injection of oppositely charged “mobile” carriers. The device exhibited a distinct rectifying effect when an alternating current (50 < f <500 mHz) was applied through the source and drain electrodes. Moreover, the function of the molecular device is programmable and erasable.
Floating Gate, Organic Field-Effect Transistor-Based Sensors towards Biomedical Applications Fabricated with Large-Area Processes over Flexible Substrates