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This study delves into the development of a novel 10 by 10 sensor array featuring 100 pressure sensor pixels, achieving remarkable sensitivity up to 888.79 kPa−1, through the innovative design of sensor structure. The critical challenge of strain sensitivity inherent is addressed in stretchable piezoresistive pressure sensors, a domain that has seen significant interest due to their potential for practical applications. This approach involves synthesizing and electrospinning polybutadiene‐urethane (PBU), a reversible cross‐linking polymer, subsequently coated with MXene nanosheets to create a conductive fabric. This fabrication technique strategically enhances sensor sensitivity by minimizing initial current values and incorporating semi‐cylindrical electrodes with Ag nanowires (AgNWs) selectively coated for optimal conductivity. The application of a pre‐strain method to electrode construction ensures strain immunity, preserving the sensor's electrical properties under expansion. The sensor array demonstrated remarkable sensitivity by consistently detecting even subtle airflow from an air gun in a wind sensing test, while a novel deep learning methodology significantly enhanced the long‐term sensing accuracy of polymer‐based stretchable mechanical sensors, marking a major advancement in sensor technology. This research presents a significant step forward in enhancing the reliability and performance of stretchable piezoresistive pressure sensors, offering a comprehensive solution to their current limitations. [ABSTRACT FROM AUTHOR]

This article reviews the increasing need for innovative transparent and conductive electrodes (TCEs) for modern optoelectronics, flexible electronics, sensors, and biomedical devices as alternatives to brittle and scarce conventional indium tin oxide (ITO). Among the various TCE materials explored, silver nanowires (AgNWs) have emerged as a promising candidate to replace ITO, thanks to their remarkable properties. However, AgNW‐based TCEs can present limitations such as thermal instability, high contact resistance, increased surface roughness, and inadequate adhesion to substrates. Incorporating secondary conductive materials with AgNWs has proven effective in mitigating these challenges, leading to high‐performance composite electrodes. This review offers a comprehensive overview of the latest advancements in AgNW‐based composite TCEs for applications in optoelectronics, flexible electronics, sensors, and biomedical devices. It covers the materials and methodologies employed to construct high‐performance composite electrodes and present a comparative analysis of various composite TCEs in terms of their optical, electrical, and mechanical properties and performance in different electronic devices. The article also discusses recent breakthroughs in enhancing TCE stability, adhesion, and contact resistance reduction by employing additional materials such as graphene, conductive polymers, and metal oxide nanoparticles. The review addresses the challenges in the field of composite TCEs, proposes potential solutions, and highlights opportunities. [ABSTRACT FROM AUTHOR]

Intense pulsed light (IPL) soldering is investigated as an alternative soldering process to conventional reflow soldering. IPL soldering is suitable for achieving a carbon‐neutral society due to its low power consumption. In addition, it has several advantages in electronic device manufacturing, including low thermal damage, short processing time, and applicability to large‐area processes. Herein, an electroless‐nickel/electroless‐palladium/immersion‐gold surface finish and Sn–3.0Ag–0.5Cu solder are used. Three IPL parameters, pulse width, pulse number, and frequency, are considered in the soldering process. The microstructures of the interface and solder matrix are observed using a field‐emission scanning electron microscope equipped with an electron probe microanalyzer. Furthermore, board‐level drop impact tests are conducted to investigate the mechanical reliability of the joints. The results show that the compositions and morphologies of intermetallic compounds (IMCs) vary with the IPL parameters, which significantly affect the reliability. Specifically, the number of drops to failure increases ≈6.7 times under optimum IPL condition compared to reflow soldering. This is because cracks propagate through the solder matrix and discontinuous IMCs. Based on the obtained results, IPL‐based soldering is a promising alternative to reflow soldering. [ABSTRACT FROM AUTHOR]

Solders, which are the most commonly used materials in electronic packaging, have been widely used for electrical interconnections. When producing a solder joint, a layer is formed on the contact pad, followed by a reflow process conducted using infrared or thermal energy. This process requires a high‐temperature environment and long heating time. Herein, an advanced approach involving photonic soldering using intense pulsed light (IPL) energy is examined thoroughly. In particular, the relation between the bonding characteristics and pulse conditions, such as the energy, frequency, and number, for the development of ultrafast, low‐damage, and large‐area bonding technology is studied. Compared with the conventional reflow, IPL soldering requires a process time of only ≈2.5% and can improve the strength by 40%. Fracture micrographs after the die shear test indicate an interfacial fracture after conventional reflow and a mixed fracture after IPL soldering; this results in the consumption of the Cu layer after the time‐consuming reaction in the reflow and the formation of an extremely refined region in the solder joint after irradiation with IPL energy. Because of its improvement with respect to the process and bonding characteristics, IPL soldering can be a candidate for innovative interconnections in microelectronics. [ABSTRACT FROM AUTHOR]

Sequential interfacial reactions of Sn‐3.0Ag‐0.5Cu solder on a new multilayer metallization, ENEPIG (electroless nickel‐electroless palladium‐immersion gold) with a 0.1‐μm‐thin Ni(P) layer (thin‐ENEPIG), during reflowing were evaluated in this study. After 20‐second reflow process, layer‐shaped (Au,Cu)Sn4 intermetallic compounds formed at the interface, and thin Ni and Pd layers underneath the Au layer remained unreacted on the polycrystalline Cu substrate. On the other hand, Au, Pd, and Ni tri‐layers in the thin ENEPIG layer were exhausted and (Cu,Ni)6Sn5 intermetallic compounds formed at the interface after reflowing for 30 seconds. [ABSTRACT FROM AUTHOR]

Transparent polymers have great potential when applied toward flexible devices as encapsulation or substrate materials in the fields of electronics, optics, biology, and so on because of their low costs and lightweight. The use of polymeric materials in bonding technology is indispensable due to the practicality of these materials. In general, polymer bonding can be achieved through the use of interlayer-like adhesives or through direct bonds such as ultrasonic or thermocompression bonding. Polydimethylsiloxane (PDMS) joints were achieved by surface modification via oxygen-argon plasma. Plasma treatment at various plasma power levels (150, 200, 250, and 300 W) was conducted on the PDMS surface with the modified surfaces being analyzed via contact angle measurement and X-ray photoelectron spectroscopy. Plasma-activated PDMS films were bonded without adhesives at 160 °C, which did not lead to deformation. The bond strength of the plasma-activated PDMS was measured using a T-peel test prior to and after bending cycles, and the optical transmittance of the specimens was also measured. The fractured surface was investigated via optical microscopy and scanning electron microscopy following adhesion testing. The experimental results revealed that the bond strength of PDMS was proportional to the employed plasma power level. The bond strength of PDMS decreased by approximately 10.8% after 100 000 bending cycles, indicating that plasma polymerization-assisted direct bonding could function as a versatile bonding method for polymeric materials. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The interfacial fracture energy of screen-printed silver nanopaste films is quantitatively measured, and the fundamental adhesion mechanism is investigated. It is found that the interfacial fracture energy at the Ag film/silicon substrate interface is critically affected by the sintering condition. The sintering temperature tunes the interfacial surface morphology of Ag films and the amount of organic residues at the interface. These factors determine the degree of interfacial toughening between the Ag film and the substrate, which directly affects the adhesion properties. The increased surface roughness of the Ag film with sufficient organic residues leads to a larger interfacial toughening at the film/substrate interface, and subsequently to an enhanced interfacial fracture energy of screen-printed Ag nanopaste films. [ABSTRACT FROM AUTHOR]