Hydrocarbons-Driven Crystallization of Polymer Semiconductors for Low-Temperature Fabrication of High-Performance Organic Field-Effect Transistors

While many high-performance polymer semiconductors are reported for organic field-effect transistors (OFETs), most require a high-temperature postdeposition annealing of channel semiconductors to achieve high performance. This negates the fundamental attribute of OFETs being a low-cost alternative to conventional high-cost silicon technologies. A facile solution process is developed through which high-performance OFETs can be fabricated without thermal annealing. The process involves incorporation of an incompatible hydrocarbon binder or wax into the channel semiconductor composition to drive rapid phase separation and instantaneous crystallization of polymer semiconductor at room temperature. The resulting composite channel semiconductor film manifests a nano/microporous surface morphology with a continuous semiconductor nanowire network. OFET mobility of up to about 5 cm² V⁻¹ s⁻¹ and on/off ratio ≥ 10⁶ are attained. These are hitherto benchmark performance characteristics for room-temperature, solution-processed polymer OFETs, which are functionally useful for many impactful applications.