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Solution‐processable organic semiconductors can serve as the basis for new products including rollable displays, tattoo‐like smart bandages for real‐time health monitoring, and conformable electronics integrated into clothing or even implanted in the human body. For such exciting commercial applications to become a reality, good device performance and uniformity over large areas are necessary. The design of new materials has progressed at an astonishing pace, but accessing their intrinsic, efficient electrical properties in large‐area flexible device arrays is difficult. The development of protocols that allow integration with industrial‐scale processing for high‐throughput manufacturing, without the need to compromise on performance, is the key for transitioning these materials to real‐life applications. In this work, large‐area arrays of organic thin‐film transistors obtained by spray‐coating the high‐mobility polymer indacenodithiophene‐co‐benzothiadiazole (IDTBT) are demonstrated. A maximum charge carrier mobility of 2.3 cm2 V−1 s−1, with a very narrow performance distribution, is obtained over surface areas of 10 cm × 10 cm. The devices retain their electrical properties when bent multiple times and at different curvatures. In addition, large arrays of highly sensitive (0.25% change in mobility for 1% humidity variation), reusable, near‐identical humidity sensors are produced in a one‐step fabrication and calibrated from 0% to 94% relative humidity. [ABSTRACT FROM AUTHOR]

The recent efforts in exploiting semiconductor nanowires (NWs) for high-performance macroelectronics are reviewed. In brief, a new concept of NW thin-film transistors (NW-TFTs) has been proposed and demonstrated from oriented semiconductor NW thin films. In NW-TFTs, the source and drain electrodes are bridged by multiple single-crystal NWs in parallel. Therefore, charges travel from source to drain within single crystals, ensuring high carrier mobility. Recent studies have shown that high-performance NW-TFTs and high-frequency circuits can be produced from silicon NWs on a variety of substrates, including glass and plastics, using a solution assembly process. The device performance of these NW-TFTs not only greatly surpasses that of solution-processed organic TFTs but is also significantly better than that of conventional amorphous or polycrystalline silicon TFTs, approaching single-crystal silicon-based devices. Further- more, with a similar framework, group III-V or II-VI NW or nanoribbon materials of high intrinsic carrier mobility or optical functionality can be assembled into thin films on flexible substrates to enable new multifunctional electronics/optoelectronics that are not possible with traditional macroelectronics. This approach thus opens a new avenue to high-performance flexible macroelectronics and will not only impact existing applications but also enable a whole new generation of flexible, wearable, or disposable electronics for computing, storage, and wireless communication. [ABSTRACT FROM AUTHOR]

A large-area, flexible, and lightweight sheet image scanner has been successfully manufactured on a plastic film by integrating high-quality organic transistors and organic photodetectors. The effective sensing area of the integrated device is 5 × 5 cm² the resolution, 36 dots per inch (dpi); and the total number of sensor cells, 5184. The pentacene transistors with top contact geometry have a channel length of 18 μm and mobility of 0.7 cm² /Vs. Organic photodetectors composed of copper phthalocyanine and 3,4,9,10-perylene-tetracarboxylic-diimide distinguish between black and white parts on paper based on the difference in their reflectivity. Since this new area-type image-capturing device does not require any optics or mechanical scanning devices, the present sheet image scanners are mechanically flexible, lightweight, shock resistant, and potentially inexpensive to manufacture; therefore, they are suitable for human-friendly mobile electronics. [ABSTRACT FROM AUTHOR]

The design and implementation of an on-pixel voltage-controlled oscillator for digital imaging applications based on a ring-oscillator circuit fabricated in amorphous silicon thin-film transistor technology is presented. Preliminary results on sensitivity, voltage to frequency gain, linearity, and simulation results of long-term stability appear promising for its application in large-area digital medical X-ray imagers. [ABSTRACT FROM AUTHOR]

Direct additive fabrication of thin‐film electronics using a high‐mobility, wide‐bandgap amorphous oxide semiconductor (AOS) can pave the way for integration of efficient power circuits with digital electronics. For power rectifiers, vertical thin‐film diodes (V‐TFDs) offer superior efficiency and higher frequency operation compared to lateral thin‐film transistors (TFTs). However, the AOS V‐TFDs reported so far require additional fabrication steps and generally suffer from low voltage handling capability. Here, these challenges are overcome by exploiting in situ reactions of molybdenum (Mo) during the solution‐process deposition of amorphous zinc tin oxide film. The oxidation of Mo forms the rectifying contact of the V‐TFD, while the simultaneous diffusion of Mo increases the diode's voltage range of operation. The resulting V‐TFDs are demonstrated in a full‐wave rectifier for wireless energy harvesting from a commercial radio‐frequency identification reader. Finally, by using the same Mo film for V‐TFD rectifying contacts and TFT gate electrodes, this process allows simultaneous fabrication of both devices without any additional steps. The integration of TFTs alongside V‐TFDs opens a new fabrication route for future low‐cost and large‐area thin‐film circuitry with embedded power management. A facile solution processing method is developed that can fabricate vertical thin‐film diodes and lateral thin‐film transistors in a single process. By exploiting in situ redox and diffusion of a bottom molybdenum electrode occurring during semiconductor deposition, the thin‐film diodes achieve high voltage and high‐frequency operation. Furthermore, their use in full‐wave rectifiers is demonstrated for wireless energy harvesting. [ABSTRACT FROM AUTHOR]

The attributes of electroplating as a low-cost, simple, scalable, and manufacturable semiconductor deposition technique for the fabrication of large-area and nanotechnology-based device applications are discussed. These strengths of electrodeposition are buttressed experimentally using techniques such as X-ray diffraction, ultraviolet-visible spectroscopy, scanning electron microscopy, atomic force microscopy, energy-dispersive X-ray spectroscopy, and photoelectrochemical cell studies. Based on the results of structural, morphological, compositional, optical, and electronic properties evaluated, it is evident that electroplating possesses the capabilities of producing high-quality semiconductors usable for producing excellent devices. In this paper we will describe the progress of electroplating techniques mainly for the deposition of semiconductor thin film materials and their treatment processes, and fabrication of solar cells. [ABSTRACT FROM AUTHOR]