Field effect transistor for sensing applications

The present invention is related to a sensing device comprising: a drain electrode, a source electrode, a gate electrode, a semi-conducting channel layer having a first side and a second opposite side, an organic sensing layer having at least one functional group which has the function which is able to bind the underlying layer to said organic sensing layer (1) and at least another functional group which has a sensing function; wherein said source electrode, said drain electrode and said gate electrode are placed on the first side of said semi-conducting channel layer, while said organic sensing layer is placed on the second side of the semi-conducting channel layer, said semi-conducting channel layer is operatively associated with said organic sensing layer, and said semi-conducting channel layer has a thickness below 5000 nm.