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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]

Phase‐change semiconductor is one of the best candidates for designing nonvolatile memory, but it has never been realized in organic semiconductors until now. Here, a phase‐changeable and high‐mobility organic semiconductor (3,6‐DATT) is first synthesized. Benefiting from the introduction of electrostatic hydrogen bond (S···H), the molecular conformation of 3,6‐DATT crystals can be reversibly modulated by the electric field and ultraviolet irradiation. Through experimental and theoretical verification, the tiny difference in molecular conformation leads to crystalline polymorphisms and dramatically distinct charge transport properties, based on which a high‐performance organic phase‐change memory transistor (OPCMT) is constructed. The OPCMT exhibits a quick programming/erasing rate (about 3 s), long retention time (more than 2 h), and large memory window (i.e., large threshold voltage shift over 30 V). This work presents a new molecule design concept for organic semiconductors with reversible molecular conformation transition and opens a novel avenue for memory devices and other functional applications. [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 instability of organic field-effect transistors (OFETs) is one key obstacle to practical application and is closely related to the unstable aggregate state of organic semiconductors (OSCs). However, the underlying reason for this instability remains unclear, and no effective solution has been developed. Herein, we find that the intrinsic tensile and compressive strains that exist in OSC films are the key origins for aggregate state instability and device degradation. We further report a strain balance strategy to stabilize the aggregate state by regulating film thickness, which is based on the unique transition from tensile strain to compressive strain with increasing film thickness. Consequently, a strain-free and ultrastable OSC film is obtained by regulating the film thickness, with which an ultrastable OFET with a five-year lifetime is realized. This work provides a deeper understanding of and a solution to the instability of OFETs and sheds light on their industrialization. Aggregate state instability is a major cause of device degradation in organic field-effect transistors. Here, authors elucidate the origin of such instability and provide a strategy to overcome it, such that devices with ultra-long lifetimes can be obtained. [ABSTRACT FROM AUTHOR]

'Regioselectivity deposition' method is developed to pattern silver electrodes facilely and efficiently by solution-process with high resolution (down to 2 μm) on different substrates in A4 paper size. With the help of this method, large-area, flexible, high-performance polymer field-effect transistors based on the silver electrodes and polyimide insulator are fabricated with bottom-contact configuration by all-solution processes. The polymer devices exhibit high performance with average field-effect mobility over 1.0 cm2 V−1 s−1 (the highest mobility up to 1.5 cm2 V−1 s−1) and excellent environmental stability and flexibility, indicating the cost effectiveness of this method for practical applications in organic electronics. [ABSTRACT FROM AUTHOR]

Highlights: [•] Polyimide is used as insulator layers in the process of photolithography for the first time. [•] Large scale, flexible and high-performance transistor arrays and circuits are fabricated. [•] The modified photolithography technique is employed to protect the polyimide in the process of photolithography. [ABSTRACT FROM AUTHOR]

Small reaction, big application! The silver mirror reaction is a straightforward way to produce silver films, and can be performed using cheap reactants in aqueous solutions. Here, it is successfully introduced into organic electronics by L. Jiang, H. Dong, G. Yu, W. Hu, and co‐workers, and applied to the process of fabricating flexible, high‐performance, large‐area, all‐solution‐processable organic fieldeffect transistors at room temperature with high resolution. [ABSTRACT FROM AUTHOR]