Polymer Adsorbed Layer Promotes Dipole Ordering in Gate Dielectrics for Organic Field-Effect Transistors

Orderly oriented dipoles at semiconductor/dielectric interfaces are conducive to the carrier transport of organic field-effect transistors (OFETs). However, it remains a challenge to prepare ordered polymer dielectrics due to the random coil feature of polymer chains. Herein, we utilized a poly(methyl methacrylate) (PMMA) adsorbed layer to tailor the chain conformations of polymer chains and achieved the ordered orientation of dipoles of polymer dielectrics. The ordered dipoles at the interface decrease the energy fluctuations and the probability of formation of Fröhlich polarons at the interface between the semiconductor and the dielectric, which promotes the carrier transport of OFETs based on poly(3-hexylthiophene) (P3HT) as the semiconductor. This work provides a new strategy for controlling the ordered orientation of dipoles in polymer dielectrics, which may further improve the performance of OFETs based on polymer dielectrics.