Organic field effect transistors (OFETs) are the basic building blocks of flexible integrated circuits and displays, and they are also promising components for next-generation electronic devices. OFET's flexibility, thinness and lightness have attracted attention and can be used in foldable electronic circuits and implantable biometric sensors. The structure of the OFET device includes an organic semiconductor layer, an insulating layer, and source and drain gate electrodes. These components allow the evaluation of basic transistor parameters, including mobility, operating voltage, and drive stability.
To manufacture OFETs, materials from conductors (for electrodes), semiconductors (for active channel materials) to insulators (for gate dielectric layers) are needed. One of the functional parameters evaluated in organic semiconductor materials is mobility (μ), which represents the speed at which holes (p-type) or electrons (n-type) in the semiconductor layer move. The production of high-speed circuits requires materials with high carrier mobility. A common feature of OFET materials is that they contain aromatic or other conjugated π-electron systems, which contribute to the delocalization of the orbital wave function. An electron withdrawing group or an electron donating group can be connected to promote the transport of holes or electrons.
Types of Organic Field Effect Transistor Materials
