A wafer-scale, 2D organic single-crystalline semiconductor revolutionizes near-field communication.

Development of high-performance printed semiconductor devices is highly desired with the expectation for the nextgeneration technologies of "printable electronics" providing simply fabricated, fl exible, large-area, low-cost, and environmentally friendly electronic products such as paper-like fl exible displays. Patterned arrays of printed organic fi eld-effect transistors (OFETs) based on chemically stable solutionprocessed organic semiconductors are regarded as key devices that operate as fundamental switching components in, for example, pixel-controlling active-matrix elements. However, performance of conventional solution-coated noncrystal organic thin-fi lm transistors has yet to be improved for practical use in general electronic circuitry. Here, newly developed arrays of patterned crystalline OFETs of air-stable compound 2,9-didecyl-dinaphtho[2,3-b:2',3'-f ]thieno[3,2-b]thiophene (C 10 -DNTT) formed from hot solution are presented. A method of oriented growth is introduced to provide the singlecrystalline fi lms of C 10 -DNTT that regulates the crystallizing direction and positions in a single process. The benchmark value, 10 cm 2 V − 1 s − 1 , of the charge mobility is achieved for the present OFETs, far exceeding the performance of former devices and opening a practical way to realize printed and fl exible electronics with suffi cient switching speed. The result is attributed to almost perfect molecular periodicity in the crystal fi lms, which allows effective intermolecular charge transport of the electrons.In the process of forming organic semiconductor fi lms from solution by naturally evaporating the solvent near room temperature, constituent molecules that are independently dispersed in the solvent, are expected to self-organize into a highly ordered assembly with the amazing speed of more than 10 10 molecules per second. [ 1 ] Since the speed of the fi lm growth is directly translated to high-throughput production, solution techniques such as spin-coating and drop-casting are very attractive for the industry. [ 2 ] Regarding the performance of the solution-processed organic fi eld-effect transistors (OFETs), their switching speed is directly determined by charge carrier mobility in the organic semiconductors, which relies on microscopic electronic properties of molecule-to-molecule charge-transfer probability and the extent of molecular ordering. Therefore, it has been intensively challenging to create high-mobility active semiconductor layers using simple solution techniques. In addition, simple methods of forming their patterned arrays during the fi lm growth have been regarded as essential technology for accelerated production of matrix devices. Here, the extent of the molecular order signifi cantly infl uences device performance through the charge carrier mobility in the semiconductor fi lms. In order to realize much higher performance than achieved in present devices, synthesis of functional π -conjugated molecules with superior selfassembling properties, in addition to their high-charge-trans...

Background:The inhibitory mechanism of A␤42 aggregation by flavonoid is fully unknown. Results: The oxidant enhanced the inhibitory activity of (ϩ)-taxifolin against A␤42 aggregation by forming A␤42-taxifolin adducts between the Lys residues and oxidized (ϩ)-taxifolin. Conclusion:The inhibitory activity of catechol-type flavonoids requires autoxidation to form an o-quinone to react with Lys. Significance: These may help design promising inhibitors against A␤42 aggregation for Alzheimer disease therapy.

Field-effect mobility as high as 5 cm2/(V s) is achieved in solution-processed organic thin-film transistors with the development of a method for growing highly-oriented crystalline films of [1]benzothieno[3,2-b]benzothiophene derivatives. A droplet of the solution is sustained at an edge of a structure on an inclined substrate, so that the crystalline domain grows in the direction of inclination. The oriented growth realizes excellent molecular ordering that manifests itself in micrometer-scale molecular terraces on the surface as a result of the self-organizing function of the material. The unprecedented performance achieved using an easy fabrication process has increased attractiveness of organic thin-film transistors for industrial applications.

High‐mobility solution‐processed organic transistors are developed based on a hybrid of solution‐crystallized air‐stable organic semiconductor 2,7‐dioctyl[1]ben­zo­thieno[3,2‐b][1] benzothiophene (C8‐­ BTBT) and 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetra­cy­anoquinodimethane (F4‐TCNQ) top layers. Charge mobility as high as 6 cm2/Vs is achieved, owing to the almost perfectly periodic crystal packing and efficient charge supply from the acceptor.

High-mobility organic transistors are fabricated on both surfaces of approximately 1-μm-thick rubrene crystals, molecularly flat over an area of 10×10μm2. A thin platelet of 9,10-diphenylanthracene single crystal and surface-passivated SiO2 are used for the gate insulators. Because of the minimized densities of hole-trapping levels at the interfaces and in the rubrene crystal, the field-induced carriers do not necessarily reside near the interface but are distributed in the bulk of the semiconductor by adjusting the two gate voltages. Making use of the highly mobile carriers in the inner crystal, the mobility is maximized to ∼43cm2∕Vs.

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transport, solubility suitable for solution processing, thermal stability sufficient for curing, and chemical stability in air. The compound 3,11-didecyldinaphtho[2,3d:2′,3′-d′]benzo [1,2-b:4,5-b′]dithiophene (C 10 -DNBDT-NW) is an example of a p-type compound. This semiconductor shows a hole mobility of 16 cm 2 V −1 s −1 , moderate solubility in common aromatic solvents such as o-dichlorobenzene (≈0.1 wt%) at 60 °C, and excellent stability up to 200 °C. [3] It has also been reported that the n-type materials N,N′-1H,1Hperfluorobutyldicyanoperylene-carboxydiimide (PDIF-CN 2 ) and benzo [1,2-c:4,5-c′] bis ([1,2,5]thiadiazole) (BBT), both of which are solution-processable in air, exhibit electron mobilities as high as 1.3 and 0.61 cm 2 V −1 s −1 , respectively. [8,9] Currently, it is anticipated that the next step in the evolution of electronics will be to establish reliable and reproducible fabrication processes for integrated electronic devices that have practical applications. As an example, hundreds of transistors must operate simultaneously in the integrated circuits of low-cost plastic sensor films [10,11] and radio-frequency identification (RFID) tags, [12,13] which are presently the most important devices associated with advances in materials science. Herein, we report a method of fabricating fully functionalized wireless digital sensor circuits, employing recent material innovations based on high-performance painted OFETs. Using these devices, it is anticipated that exceptional quantities of data will be able to be extracted from low-cost film sensors, leading to a so-called Internet-of-Things community. This technology is based on continuously painting uniform single-crystalline films composed of p-and n-type organic semiconductors that are situated next to one another, allowing complementary circuits to be designed by connecting the films. To demonstrate the exceptional reliability and performance of such devices, this work performed the firstever successful demonstration of solution-processed digital sensor circuits incorporating binary counters, selectors, a thermosensor, an analog-digital converter, and a wireless communication unit. We note that mobility values close to the maximum possible values were realized in regions of the semiconductor Recent progress in the development of organic semiconductor materials has improved the performance of both p-and n-type transistors. Currently, it is anticipated that the next step in the evolution of electronics will be to establish a reliable fabrication technique for integrated electronic devices such as plastic sensor films and radio-frequency identification (RFID) tags. Herein, a new fabrication process to grow line-shaped organic single-crystalline films with widths on the order of one mm is reported. To realize large-scale complementary logic circuits, it is necessary to precisely control the growth conditions of p-type and n-type semiconductors when painting on different areas on the same substrate. This method makes it possible to fabricate highly ori...