An Overview of Organic Field-Effect Sensors

To obtain a sensor from an OFET, it is necessary to achieve, in one of the layers that form the device, a specific sensitivity/selectivity toward an external stimulus applied to the device. If this is a chemical stimulus, often a specific chemical functionalization of one of the device layers is required. Organic semiconductors, though intrinsically affected by many, still unsolved, 

In an active device, like an organic field-effect transistor, chemical tailoring can be applied not only to the semiconductor but also to metallic and insulating layers, thus allowing different localizations of the device-sensing area. This possibility broadens the set of sensing principles exploitable for these devices. In addition, from the electrical characterization of an active device it is possible to simultaneously extract different parameters, which correlate to the identification of a chemical species in a mixture. In this way it is possible to obtain a sort of fingerprint of a compound [5]. 

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