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The disordered chain arrangement of polymer dielectrics has complex both internal and external effects on system performance, which generally stimulates the weak acquisition and grain boundaries of vapor‐deposited organic small molecule films (VDOSMFs) with thermally activated charge transport. As a result, achieving "band‐like" transmission of VDOSMs on polymer dielectrics is attempting to prove to be a major challenge. Three types of bi‐polymer dielectrics are developed to modulate charge transport from thermally activated mode to "band‐like" transport at the interfacial level. The bottom consisting of a polyimide layer is critical to interfacial modulation, which shows the selectively binding capability with up‐dielectric layers to realize the modulation of charge transport, as corroborated by interface characterization and density functional‐based tight‐binding calculation. The findings provide an effective strategy for modulating the charge transport through polymer dielectric engineering and also recommend a podium to further comprehend the electrical characteristics of small molecules in organic thin‐film transistors. [ABSTRACT FROM AUTHOR]

Molecule design of organic semiconductors (OSCs) for eliminating photoresponse and maintaining high charge mobility concurrently is beneficial to realize intrinsically photostable and high‐performance organic field‐effect transistors (OFETs), which has never been reported. Here, a novel organic semiconductor TFP‐TT‐TPA with a centrosymmetric structure is synthesized. Remarkably, OFETs with TFP‐TT‐TPA show negligible photoresponse under light intensity up to 170.4 mW cm−2 (higher than sunlight intensity, about 138 mW cm−2), which ensures that the devices can work stably under sunlight. Through the single‐crystal structure and exciton dynamics analysis, it is found that the specific structure design can make strong intermolecular D–A interaction that occurs in the aggregate state, which facilitates the process of exciton quenching and thus enables the photostable OFETs. This study provides a new strategy for the design of organic semiconductors with intrinsic photostability and the construction of photostable organic optoelectronic devices for applications in light environment. [ABSTRACT FROM AUTHOR]

The study of monolayer organic field‐effect transistors (MOFETs) provides an effective way to investigate the intrinsic charge transport of semiconductors. To date, the research based on organic monolayers on polymeric dielectrics lays far behind that on inorganic dielectrics and the realization of a bulk‐like carrier mobility on pure polymer dielectrics is still a formidable challenge for MOFETs. Herein, a quasi‐monolayer coverage of pentacene film with orthorhombic phase is grown on the poly (amic acid) (PAA) dielectric layer. More significantly, charge density redistribution occurs at the interface between the pentacene and PAA caused by electron transfer from pentacene to the PAA dielectric layer, which is verified by theoretical simulations and experiments. As a consequence, an enhanced hole accumulation layer is formed and pentacene‐based MOFETs on pure polymer dielectrics exhibit bulk‐like carrier mobilities of up to 13.7 cm2 V−1 s−1 from the saturation region at low VGS, 9.1 cm2 V−1 s−1 at high VGS and 7.6 cm2 V−1 s−1 from the linear region, which presents one of the best results of previously reported MOFETs so far and indicates that the monolayer semiconductor growing on pure polymer dielectric could produce highly efficient charge transport. [ABSTRACT FROM AUTHOR]