An organic field-effect transistor and a method of making the same include a self-assembled monolayer (SAM) of bifunctional molecules disposed between a pair of electrodes as a channel material. The pair of electrodes and the SAM of bifunctional molecules are formed above an insulating layer, in which each of the bifunctional molecules comprises a functionality at a first end that covalently bonds to the insulating layer, and an end-cap functionality at a second end that includes a conjugated bond. The SAM of bifunctional molecules may be polymerized SAM to form a conjugated polymer strand extending between the pair of electrodes.