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A flexible superconducting yarn composed of twisted niobium nitride (NbN) nanofibrils is developed and exhibited a superconducting transition temperature that met the reported record of ≈17 K. NbN is sputter‐deposited onto a template of aligned single‐layer carbon nanotube (CNT) sheets and subsequently processed by post‐Joule heat annealing following the insertion of twists. Considering self‐Joule heating approaches the level of incandescent light emission, the melting, reflow, and recrystallization of the NbN layer around each CNT template occurred, considerably enhancing the macroscopic superconducting properties of the NbN nanofibrillar yarn, including the critical current density and critical magnetic field. Furthermore, the superconducting performance, which degrades as a result of mechanical damage to the internal structure under excessive stress such as bending, can be restored by the reflow of the NbN during this process. Considering the melting point of NbN is higher than 2800 K, the proposed incandescent light‐emission‐driven Joule self‐heating process is considered an effective method for improving the properties of CNT‐templated metal hybrid yarns. [ABSTRACT FROM AUTHOR]

Stainless steel (SS) is well known for its remarkable versatility. Besides the importance of passivation film for durability and stability of SS, the composition and morphology of passive surface layer have to be precisely modified to create an alloy that is optimal for specific purposes. Herein, we report on the electrochemical preparation of nickel‐enriched passive film which is accomplished by the preferential adsorption of glucose on nickel species among constituents of SS. The presence of nickel‐rich surface and the exposure of nickel on the outmost surface layer participating in surface reactions are verified by monitoring redox couple of Ni2+/Ni3+ as well as elemental analyses (TEM‐Energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy). Reversible interchange of nickel‐rich into iron‐rich surface and vice versa is possible by adding or removing glucose. We find that molecules having more than tri‐dentate of hydroxy groups (e. g. glycerol) is required for the formation of Ni‐rich surface (chelate effect). [ABSTRACT FROM AUTHOR]

The overarching goal herein is to identify the factors dominating the performance of a‐IGZO‐based memristors. Despite the highest on/off ratio, greater than 104 with a preferred minimal set/reset bias achieved from a‐IGZO‐based memristors, it is observed that the switching performance and stability/reliability of the devices is significantly dominated by the VO·· density and metallization material, depending on their reactivity with IGZO. As the first governing factor, ensuring optimal VO·· concentration in the switching layer IGZO (VO··/OOx ratio 24.3% in this study) is crucial to obtain the tractable formation and rupture of conduction filament. Neither higher nor lower VO·· density than the optimized results in detrimental reliability issues, which may be ascribed to an uncontrollable filament in an abundant vacancy environment or a weak conducting path, respectively. As the second governing mechanism determining the memristor performance and reliability, it is suggested that metallization materials need to be carefully selected based on the thermodynamic redox potential and interfacial stability of the metallization material with IGZO. Metallization materials with larger reduction potential and interfacial stability are found to yield higher switching on/off ratio and greater device performance reliability. [ABSTRACT FROM AUTHOR]

According as phase‐shift layer and OPC techniques are applied to photomasks for novel display with a resolution of higher than 1000ppi, it is indispensable to qualify photomask printability of area of interest‐ especially the area where the photomask repair processes were performed ‐ before the photomask is used in panel manufacturing line[1]. For this photomask qualification, new imaging system to emulate photo exposure process was developed; which enables to assess the printability of photomask by analyzing the aerial image. To verify the results from the imaging system, simulation and analytical solution were performed with various optical parameters such as NA and coherence. As an application of the imaging system, how to quantify the pattern abnormality using process window analysis and to measure in maskshop the mask error enhancement factor in aerial image was introduced. [ABSTRACT FROM AUTHOR]

Flexible superconducting yarns consisting of sputter-deposited NbN nanowires on highly aligned carbon nanotube (CNT) array sheets are reported. In the microscopic view, the NbN nanowires are formed on top of individual CNT fibrils, and the superconductivity property of the twist-spun NbN-CNT yarn system is comparable to that of a typical NbN thin film on a normal solid substrate. Because of its intrinsic porosity, the system exhibits superior mechanical flexibility with a small bending radius. It also remains a superconducting state even when subjected to severe mechanical deformations, primarily due to the proximity superconductivity through carbon nanotube bundles. The results demonstrate the possibility of fabricating flexible superconducting yarns in a conventional thin-film deposition process, using ultraflexible free-standing CNT sheets as a template. In addition, preliminary tests on reducing the normal-state resistance toward superconducting cable applications are presented. [ABSTRACT FROM AUTHOR]