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Transparent materials widely used in applications such as eyewear, solar cells, and optical devices, often suffer from environmental challenges including fogging, surface contamination, and mechanical deformation. However, a universal strategy that resolves all these issues in a single platform remains to be resolved. Herein, a monolithic micropillar structure based on polydimethylsiloxane (PDMS) elastomer is prepared followed by subsequent assembly of hydrogel micropatterns in between the micropillar array using inkjet printing to achieve flexible wet‐style superhydrophobic antifogging tapes that are applicable to various transparent materials and curvatures. The monolithic micropillar structure with low‐surface‐energy characteristics facilitates easy removal of surface contaminants by rinsing with water while granting mechanical durability. In addition, micropatterning of hydrogels via inkjet printing not only enables to maintain optical transparency in a fogging environment but also makes the fabrication procedure more scalable. Furthermore, the strong adhesion between the hydrogel and the elastomer is shown to provide enhanced stability under repeated stretching cycles and long‐term exposure to water while the presence of a loosely cross‐linked PDMS at the bottom of the tape made it applicable to a wide range of transparent substrates without using additional adhesives. [ABSTRACT FROM AUTHOR]

Direct printing of conjugated polymer thin‐film transistors enables the fabrication of deformable devices with low cost, high throughput, and large area. However, a relatively poor device performance of printed devices remains a major obstacle to their application in high‐end display backplanes and integrated circuits. In this study, high‐performance and highly stackable printed organic transistors is developed, arrays, and circuits using a near‐amorphous polymer, indacenodithiophene‐co‐benzothiadiazole (IDT‐BT). The printed devices exhibited high saturation mobility (>1 cm2 V−1 s−1), high on/off ratio (>107), and low subthreshold slope (245 mV dec−1). In addition, 16 × 16 printed IDT‐BT arrays achieved 100% fabrication yield, with excellent device‐to‐device uniformity and low variations of mobility (9.55%) and threshold voltage (4.51%), and good operational and environmental stability (>365 days). Furthermore, five stacked 3D transistors are demonstrated with an excellent 3D uniformity without compromising device performance due to a low required thermal budget for processing amorphous IDT‐BT. Finally, a new concept of 3D universal logic gate with high voltage gain (33.91 V/V) and record density (100 printed transistors per cm2) is proposed and fabricated, which is relevant for the commercialization of low‐cost printed display backplanes and high‐density integrated circuits based on highly processable polymeric semiconductors. [ABSTRACT FROM AUTHOR]

Due to their inherent flexibility, solution-processable conjugated polymers are increasingly being considered for the cost-effective production of thin-film semiconductor devices used in Internet of Everything (IoE) applications. With considerable improvements in charge carrier mobilities, the final challenge impeding the commercialization of conjugated polymers may be improving their environmental and electrical stabilities. Recent studies have improved the stability of computing devices (i.e., transistors) by eliminating interface traps and water molecules within conjugated polymers. However, the stability issue of Schottky diodes, which play a crucial role in configuring thin-film IoE devices used in wireless communication and energy harvesting, has been largely overlooked. This study reveals that aluminum, which is commonly used as a cathode metal in polymer Schottky diodes, creates a nonstoichiometric effect when deposited on conjugated polymers, thereby leading to the formation of charge traps over time, which reduces the rectification ratio of the Schottky diodes and induces a significant bias stress effect during operation. To address this issue, we introduce a zinc-oxide sacrificial interlayer between the conjugated polymer and cathode. This interlayer effectively eliminates the penetrated Al metal or ionized Al-induced nonstoichiometric effect without reducing the charge injection efficiency, achieving exceptional environmental and operational stability. The printed polymer Schottky diodes demonstrate consistent rectifying operation at 13.56 MHz for several months with negligible changes in electrical characteristics. [ABSTRACT FROM AUTHOR]