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Abstract: We report on rational synthesis and optical characteristics of highly crystallined ZnO nanorods which were grown by a facile chemical vapor transport method. Temperature-dependent photoluminescence spectra of as-fabricated ZnO nanorods are dominated by near-band-edge emission with a characteristic fine structure due to high crystallinity. Furthermore, the recombination emission involving carrier dynamics of near-band-edge emission in ZnO nanorods was systematically investigated by temperature-dependent time-resolved photoluminescence spectroscopy. Recombination peaks pertaining to the exciton emissions are monitored and resolved in both temporal and spatial regimes. [Copyright &y& Elsevier]

The gate oxide quality in SiC MOSFETs presents a significant challenge, particularly at temperatures exceeding 175 °C. This predicament arises from the gate oxide interface's propensity to trap or release charge carriers, compromising device ruggedness. In mainstream SiC MOSFETs, the gate oxide in the trench corner confronts the demanding task of enduring higher electric field strengths, thereby posing a substantial risk to overall device reliability. As a result, research entities are proactively involved in improving the SiC/oxide interfaces to enhance the devices' resilience against elevated E -field. This endeavor aims to maintain the favorable characteristics of the trench SiC MOSFETs, including low on-state resistance, minimal parasitic capacitance, and exceptional switching performance. Thus, the implementation of a streamlined process becomes crucial to fortify the trench corner, ultimately yielding boosted E -field immunity. In this report, our research focuses on enhancing the reliability of trench corner in SiC MOSFET devices. Specifically, we employ spacer etch technology to selectively shield the trench corner with high-K heterolayers, thereby enhancing the device's ability to withstand higher E -field strengths (59.2 % reinforcement) while mitigating the risk of hidden defects. Importantly, compared to the structure without protection, at high-K shielded layer contact angles ranging from 90 to 150°, the E -field decreases, correlated the enhanced reinforcement at larger angles. Furthermore, such technology enables higher E-fields and greater circuit capacity at the bottom of trench gate, leading to enhanced device reliability. Our studies confirm that the developed device structure exhibits simplicity, reliability, maturity, and controllability, rendering it suitable for large-scale integration applications. • The present work focuses on improving the SiC/oxide interfaces to enhance the resilience of SiC MOSFETs against elevated E-field, aiming to preserve the favorable characteristics of trench SiC MOSFETs. • The implementation of a streamlined process is crucial to fortify the trench corner and enhance E-field immunity, thereby boosting the reliability of SiC MOSFET devices. • Spacer etch technology is employed to selectively shield the trench corner with high-K heterolayers, resulting in a 59.2 % reinforcement of the device's ability to withstand higher E-field strengths while mitigating the risk of hidden defects. • The developed device structure, fortified by spacer etch technology, exhibits simplicity, reliability, maturity, and controllability, making it well-suited for large-scale integration applications. • The developed technology enables higher E-fields and greater circuit capacity at the bottom of the trench gate, leading to enhanced device reliability. [ABSTRACT FROM AUTHOR]

Abstract: ZnO nanowires were grown on Au-coated Si (100) substrates by the method of vapor–liquid–solid (VLS) growth processing technique. The effects of supply time of Ar gas current on morphology and microstructure of Au-catalyzed ZnO nanowires were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy. The results showed that the morphologies of ZnO nanostructures strongly depended on the time of flowing Ar gas. When the time of flowing Ar gas was 90s, ZnO showed nanowires with hexagonal structure. Their diameters and lengths were 160nm and 20μm, respectively, on average, and the Raman scattering peak located at 438cm−1 reached maximum intensity. The results also showed that the ZnO growth could be patterned by controlling the initial position of Au-coated area on the Si substrates. [Copyright &y& Elsevier]

• Heat treatment interval of Fe 80 Zr 9 B 10 Cu 1 alloy is as high as 154.7 K. • Composition, microstructure and magnetic properties correlation is revealed and elaborated. • Composition impacts on crystallizations of FeZrB and FeZrBCu alloys are established. • Thermal stability of H c in FeZrBCu alloys is developed with composition and annealing engineering. Amorphous alloy ribbons of FeZrB and FeZrBCu (1 at.% Cu) are synthesized and annealed in vacuum. Synergistic effects of the addition of Cu, and different proportions of Fe, Zr and B, on both crystallization and magnetic property of FeZrB alloys, are systematically investigated. The addition of Cu results in a lower thermal stability of FeZrBCu alloys compared to FeZrB alloys, while the heat treatment interval of FeZrBCu alloys is wider. The crystallizations of FeZrB alloys differ from each other; in contrast, those of FeZrBCu alloys are similar. The coercivity (H c) is large for FeZrB alloys in general, but small for FeZrBCu alloys at the initial annealing stage due to the nanocrystalline structure in the two-phases and the fine α -Fe nanocrystals. All developed FeZrBCu alloys demonstrate low values of H c and excellent thermal stability of H c below 898 K. The correlated mechanisms linking crystallization and magnetic characteristics are discussed in detail. [ABSTRACT FROM AUTHOR]

Eu2+-activated Ba 5 SiO 4 Cl 6 phosphors with blue and green emissions were synthesized by a solid-state reaction route in a reduction atmosphere. The obtained crystal structure and photoluminescent properties indicated that three various Ba2+ ions sites were partially occupied by the Eu2+ ions. The optimal doping content for Eu2+ ions in the Ba 5 SiO 4 Cl 6 system was 5 mol%. The electric dipole-dipole interaction was attributed to the involved concentration quenching effect. The thermal resistance performance was identified by using the temperature-dependent emission spectra. Importantly, the internal quantum efficiency of the established final products reached up to 50.8%. Through utilizing the diverse sensitivities of blue and green emissions from Eu2+ ions to the temperature, a neoteric optical thermometer with a high absolute and relative sensor sensitivity of 0.031 K-1 and 0.87% K−1, respectively, at 498 K was achieved. By integrating the resultant cyan phosphors, commercial CaAlSiN 3 :Eu2+ red phosphors and a near-ultraviolet chip, the warm white light-emitting diodes with admirable colorific properties were integrated and manufactured. The complementary results elaborate that the Eu2+-activated Ba 5 SiO 4 Cl 6 phosphors are bifunctional platforms for both optical thermometer and indoor illumination. • The resultant phosphors exhibited visible cyan emission when excited at 397 nm. • The dipole-dipole interaction contributed to the concentration quenching mechanism. • The resultant phosphors possessed good thermal stability and high quantum efficiency. • The Sa and Sr values of the products was 0.031 K−1 and. • The LED lamp emitted brightness white light with superior photoelectric properties. [ABSTRACT FROM AUTHOR]