Molecular orbital energy level engineering in organic transistors

The application of heterostructure concepts to organic field effects transistors (FETs) is briefly reviewed. In particular, the physics of operation of α‐sexithiophene‐ and C 60 ‐based FETs—which can act as p‐ or n‐channel transistors depending on the sign and magnitude of the gate bias—and of isotype heterostructure FETs is outlined. In the latter, both active materials, e.g., an aromatic diamine and α‐sexithiophene, transport the same (majority) carrier type.