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

Building on significant developments in materials science and printing technologies, organic semiconductors (OSCs) promise an ideal platform for the production of printed electronic circuits. However, whether their unique solution-processing capability can facilitate the reliable mass manufacture of integrated circuits with reasonable areal coverage, and to what extent mass production of solution-processed electronic devices would allow substantial reductions in manufacturing costs, remain controversial. In the present study, we successfully manufactured a 4-inch (c.a. 100 mm) organic single-crystalline wafer via a simple, one-shot printing technique, on which 1,600 organic transistors were integrated and characterized. Owing to their single-crystalline nature, we were able to verify remarkably high reliability and reproducibility, with mobilities up to 10 cm2 V−1 s−1, a near-zero turn-on voltage, and excellent on-off ratio of approximately 107. This work provides a critical milestone in printed electronics, enabling industry-level manufacturing of OSC devices concomitantly with lowered manufacturing costs.

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...

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the other hand, it was recently reported by our group that inchsize single-crystalline fi lms with unprecedentedly high carrier mobility can be fabricated from solution using a simple "edgecasting" method. [11][12][13] In this study, we aim to link the highmobility of solution-processed organic crystalline fi lms to a high dynamic response in organic transistors for both p-type and n-type operation by micropatterning the crystalline semiconductors and source/drain electrodes. The cut-off frequency f c of a transistor in the linear regime is described aswhere V D is the applied drain voltage, and L and W are the channel length and width, respectively. µ eff is the effective carrier mobility of an organic semiconductor, including the effects of contact resistance, C para is the parasitic gate capacitance, and c i WL represents the channel capacitance. In the saturation regime, V D is replaced by the gate voltage V G . From Equation ( 1) , it is clear that short-channel high-mobility transistors are strongly important to raise up the maximum operational speed of organic transistors. To realize a high fi eld-effect mobility in a short-channel device, it is crucial to reduce the contact resistance between the organic materials and the contact electrodes, which has been a challenging issue in organic transistors. In this Communication, top-contact organic confi gurations were adopted to realize extremely low contact resistances of 123 Ω cm for p-type transistors and 1.2 kΩ cm for n-type transistors, in which the contact electrodes were fabricated using photolithography process on solution-processed organic semiconductors. Complementary ring oscillators consisting of p-type and n-type transistors were demonstrated in ambient conditions to examine the operational speed of the organic circuits. Moreover, organic rectifi ers based on high-speed p-type transistors in which the drain and gate electrodes were diodeconnected were examined to determine their dynamic response speed in rectifying AC signals to DC output voltages at frequencies above 22 MHz. In the design of logic circuits, complementary circuits have the advantage of low power consumption, so the mainstream advancement of silicon technology has been based on complementary metal-oxide-semiconductor (CMOS) circuits. In organic transistors, stable n-type operation in ambient conditions has been a crucial issue because of the unstable Organic complementary circuits based on organic semiconductors have been proposed to enable attractive devices such as fl exible, or wearable organic devices. [1][2][3][4][5] Radio-frequency identifi cation (RFID) tags are one prospective application because organic devices are low-cost, light-weight, and fl exible, which are attractive features for this application. [6][7][8] One of the most important features of organic semiconductor materials is the strong self-aggregation of molecules, which enables fi ne crystalline fi lms to be easily formed, even at room temperature. This strong self-aggregation of organic materials also enables ...