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A new structure of flexible transparent electrodes is reported, featuring a metal mesh fully embedded and mechanically anchored in a flexible substrate, and a cost-effective solution-based fabrication strategy for this new transparent electrode. The embedded nature of the metal-mesh electrodes provides a series of advantages, including surface smoothness that is crucial for device fabrication, mechanical stability under high bending stress, strong adhesion to the substrate with excellent flexibility, and favorable resistance against moisture, oxygen, and chemicals. The novel fabrication process replaces vacuum-based metal deposition with an electrodeposition process and is potentially suitable for high-throughput, large-volume, and low-cost production. In particular, this strategy enables fabrication of a high-aspect-ratio (thickness to linewidth) metal mesh, substantially improving conductivity without considerably sacrificing transparency. Various prototype flexible transparent electrodes are demonstrated with transmittance higher than 90% and sheet resistance below 1 ohm sq⁻¹, as well as extremely high figures of merit up to 1.5 × 10⁴, which are among the highest reported values in recent studies. Finally using our embedded metal-mesh electrode, a flexible transparent thin-film heater is demonstrated with a low power density requirement, rapid response time, and a low operating voltage.

Vacuum-free solution-processed fabrication of flexible embedded metal-mesh transparent electrodes is demonstrated. The fabrication features a combination of lithography, electrodeposition, and imprint transfer, which is scalable for large-area high-throughput production with sub-micrometer linewidth. A self-anchoring structure of thick metal mesh contributes to excellent stability and a high electrical to optical conductivity ratio of up to 1.5 × 10⁴.

A thermally and mechanically robust, smooth, and transparent conductor composed of silver nanowires embedded in a colorless polyimide substrate is introduced by C. B. Arnold and co-workers on page 7428. This material is a new substrate-cum-electrode for optoelectronics devices and exhibits excellent thermal, mechanical, and chemical stability. As a substrate for a flexible organic light-emitting diode, improved device performance is achieved compared to a control device made on ITO coated glass.

In this work, a thermally and mechanically robust, smooth transparent conductor composed of silver nanowires embedded in a colorless polyimide substrate is introduced. The polyimide is exceptionally chemically, mechanically, and thermally stable. While silver nanowire networks tend not to be thermally stable to high temperatures, the addition of a titania coating on the nano­wires dramatically increases their thermal stability. This allows for the polyimide to be thermally imidized at 360 °C with the silver nanowires in place, creating a smooth (<1 nm root mean square roughness), conductive surface. These transparent conducting substrate-cum-electrodes exhibit a conductivity ratio figure of merit of 272, significantly outperforming commercially available indium-tin-oxide (ITO)-coated plastics. The conductive polymide is subjected to various mechanical tests and is used as a substrate for a thermally deposited, flexible, organic light-emitting diode, which shows improved device performance compared to a control device made on ITO coated glass.

A fully solution processed composite material of a colorless polyimide, titania, and silver nanowires is presented. This material is a new substrate-cum-electrode for optoelectronics devices, which exhibits excellent thermal, mechanical, and chemical stability. A green phosphorescent organic light-emitting diode device fabricated atop this electrode outperforms an indium-tin-oxide-on-glass substrate-cum-electrode control device.

The performance of a flexible transparent conductive electrode with extremely smooth topography capable of withstanding thermal processing at 300 °C for at least 6 h with little change in sheet resistance and optical clarity is reported. In depth investigation is performed on atomic layer deposition (ALD) deposited ZnO on Ag nanowires (NWs) with regard to thermal and atmospheric corrosion stability. The ZnO coated nanowire networks are embedded within the surface of a polyimide matrix, and the <2 nm roughness freestanding ­electrode is used to fabricate a white polymer light emitting diode (PLED). PLEDs obtained using the ZnO-AgNW-polyimide substrate exhibit comparable performance to indium tin oxide (ITO)/glass based devices, verifying its efficacy for use in optoelectronic devices requiring high processing temperatures.

Silver nanowires are made thermally stable with a thin layer of ZnO deposited using atomic layer deposition. This ZnO layer prevents the melting and coalescence of AgNWs observed at annealing temperatures above 180 °C, while maintaining a porous network structure. When transparent, colorless polyimide is infiltrated between the nanowires, the resulting freestanding films are able to withstand 300 °C annealing for over 6 h, showing little to no degradation in electrical or optical properties.

Stretchable gold microstructures are reliably transferred onto an extra-soft elastomeric substrate. Several major challenges, including failure-free transfer and reliable bonding with the substrate, are addressed. The simple and reproducible fabrication allows extensive study and optimization of the stretchability of meanders in terms of thickness, geometry, and substrate. The results provide new insights for designing stretchable electronics and novel routes for stretchrelated, mechanobiological cell-interface applications.

A novel flexible encapsulation method (Flex Lami-capsulation) is reported, which can be applied in the roll-to-roll process for mass production of organic electronic devices. Flex Lami-capsulation is very simple, fast, and getter-free, and is as effective as glass encapsulation. Use of this method is feasible in large-area flexible displays and does not have the drawbacks of conventional encapsulation methods.

Extreme ultraviolet lithography (EUVL) is the leading technology for enabling miniaturization of computational components over the next decade. Next-generation resists will need to meet demanding performance criteria of 10 nm critical dimension, 1.2 nm line-edge roughness, and 20 mJ cm^–2 exposure dose. Here, the current state of the development of EUV resist materials is reviewed. First, pattern formation in resist materials is described and the Hansen solubility sphere (HSS) is used as a framework for understanding the pattern-development process. Then, recent progress in EUVL resist chemistry and characterization is discussed. Incremental advances are obtained by transferring chemically amplified resist materials developed for 193 nm lithography to EUV wavelengths. Significant advances will result from synthesizing high-absorbance resist materials using heavier atoms. In the framework of the HSS model, these materials have significant room for improvement and thus offer great promise as high-performance EUV resists for patterning of sub-10 nm features.

Extreme ultraviolet lithography is the future technology for high-resolution high-throughput fabrication of computation devices. Resist technology needs to advance significantly to reach single-digit-nanometer pattern size. Recent progress in materials design and characterization is briefly summarized with an emphasis on future design requirements.

In this work, the application of an aluminum (Al)/multiwall carbon nanotube (MWCNT)/Al, multilayered electrode to flexible, high-efficiency, alternating current driven organic electroluminescent devices (AC-OEL), is reported. The electrode is fabricated by sandwiching a spray-cast nanonetwork film of MWCNTs between two evaporated layers of Al. The resulting composite film facilitates a uniform charge distribution across a robust crack-free electrode under various bending angles. It is demonstrated that these composite electrodes stabilize the power efficiency of flexible devices for bending angles up to 120°, with AC-OEL device power efficiencies of ≈22 lm W⁻¹ at luminances of ≈4000 cd m⁻² (using no output coupling). Microscopic examination of the Al/MWCNTs/Al electrode after bending of up to 1300 cycles suggests that the nanotubes significantly enhance the mechanical properties of the thin Al layers while providing a moderate modification to the work function of the metal. While the realization of robust, high-brightness, and high-efficiency AC-OEL devices is potentially important in their future lighting applications, it is anticipated that this to also have significant impact in standard organic light emitting diodes lighting applications.

Nanocomposite cathode structures—in this case metals together with multiwalled nanotubes—with the aim of combining mechanical and electronic properties to achieve better performance in an organic flexible are examined. A flexible high-efficiency alternating current (AC) driven field-induced polymer electroluminescent) device is chosen as the platform system with the understanding that this approach to organic devices clearly points to organic light emitting diodes, organic thin-film transistors, and other flexible systems.