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Pain‐perceptual Nociceptors (PPNs) in the biological sensory system are critical for the human body to perceive noxious stimuli from the outside world and start appropriate motor responses to minimize potential physical damage. Realization artificial nociceptors with unique synaptic and pain‐perceptual functions of the human nervous system is a key step to develop the next‐generation artificial intelligence systems. Here, an artificial pain‐perceptual device based on an ionic liquid‐polymer solid‐state electrolyte‐gated poly(3‐hexylthiophene) (P3HT) transistor is reported. With the drift motion of mobile ions in the electrolyte layer and the formation of an electric double layer (EDL) at electrolyte/semiconductor interface under an applied electric field, the channel conductance can be tuned progressively to exhibit synaptic weight modulation function. On top of the artificial synaptic functions, the P3HT/electrolyte‐based transistor successfully emulates the pain‐perception process in a biological nociceptor, with all unique features of threshold, no adaptation, sensitization/desensitization, and relaxation. Moreover, the pain conditioning process (i.e., hyperalgesic response, and pain extinction effect) through associative learning is demonstrated using the artificial synaptic transistor, indicating its potential application in bio‐inspired neural systems. [ABSTRACT FROM AUTHOR]

Roll-to-roll (R2R) printing technologies have been widely adopted in a variety of engineering fields, e.g., organic photovoltaics and flexible electronics, owing to the advantages of cost and throughput. Although a minimum feature size of 100 nm has been demonstrated on R2R systems, the layer to layer registration accuracy (i.e., overlay accuracy) still remains as low as tens of microns, which prevents the fabrication of common electronic and functional devices, such as transistors. To realize the full potential of R2R technologies, the registration accuracy must be improved to match the printing resolution, i.e., 100s nm. To address the issue, we have developed a multi-layer R2R system with multiple-input multiple-output (MIMO) closed-loop control that achieves submicron level alignment precision for large-scale continuous printing processes. The enabling elements in the multi-layer R2R system include: (1) new vision-based alignment algorithm/method, which provides 100s nm position detection capability based on low-cost cameras; and (2) custom-built five-axis compliant roller positioner. Experimental results show that the compliant roller positioner has a ±1 mm range with 100s nm precision in X, Y, and Z axes respectively. For correcting in-plane web errors, the roller positioner can achieve a range of 1 mm with < 1 μm precision, realizing multi-layer R2R printing with submicron overlay accuracy. Based on the new methods, a gate/source-drain multi-layer electrode structure for field-effect transistors (FETs) has been designed and fabricated on a 4-inch PET web, demonstrating better than 1 μm overlay precision in fabricating flexible electronics on a R2R platform for the first time. • The first demonstration of a multi-layer R2R printing system that achieves better than 1 μm overlay accuracy. • The five-axis roller positioner actively corrects position errors with a precision of ±200 nm and ±2 μrad. • The new alignment solution achieves a large detection range (> 1 mm) with high-resolution (10s nm) based on low-cost cameras. • R2R printing of a multi-layer structure, i.e., FETs, was demonstrated on a 4-inch PET web with < 1 μm overlay precision. [ABSTRACT FROM AUTHOR]

Many advanced materials have been developed for organic field‐effect transistors (OFETs) or thin‐film transistors (TFTs) based on organic and organic hybrid materials. However, although many new OFETs exhibit superior characteristic parameters (such as high mobility), most of them show nonideal performances that have strongly limited progress in the design of molecules, the understanding of transport mechanisms, and the circuit applications of OFETs. In this review, the device physics of ideal and nonideal OFETs is discussed first to understand the factors that limit effective mobility in semiconducting channels, distort the potential distribution, or reduce the drift electric field. Then, recent advances in optimizing the material combinations, device structures, and fabrications of OFETs toward ideal transistors are discussed. Based on the good control of materials and interfaces, some new and novel concepts to utilize the nonideal properties of OFETs to build low‐power circuits and integrated sensors are also discussed. [ABSTRACT FROM AUTHOR]

The rapid sintering of printable metal nanoparticle inks is vital for the industrial mass production of electronic devices. In this paper, we report a rapid laser annealing method for printed Ag nanoparticle-based inks. We also fabricate Ag circuits and organic thin-film transistors (OTFTs) on flexible plastic substrates through spontaneous patterning under deep ultraviolet (DUV) exposure. Compared to the conventional thermal annealing, laser annealing significantly reduces the processing time from 3600 to 10 s while preventing damage caused by excessive heat. The OTFT with laser-annealed Ag source/drain electrodes achieved good performance with saturated mobility of 1.68 cm $^{{2}}\cdot \text{V}^{-{1}}\cdot \text{s}^{-{1}}$ , high-reliability factor of 86.75%, and large saturated drain current resulting from the small channel resistance. This rapid laser annealing method is feasible for printing flexible electronics using metal nanoparticle-based inks in industrial mass production. [ABSTRACT FROM AUTHOR]

Nonideal Transistors: Understanding, Optimizing, and Utilizing Nonideal Transistors Based on Organic or Organic Hybrid Semiconductors (Adv. Funct. Keywords: device physics; field-effect transistor; organic semiconductor; reliability; thin-film transistor EN device physics field-effect transistor organic semiconductor reliability thin-film transistor 1 1 1 05/18/20 20200515 NES 200515 In article number 1903889, Chuan Liu and co-workers review the origins and critical factors that lead to organic field-effect transistors (OFETs) with deviations from the ideal device models in terms of device physics. Device physics, field-effect transistor, organic semiconductor, reliability, thin-film transistor. [Extracted from the article]