Electronic Materials Letters最新文献

The ZnO and CeO₂ nanostructures were prepared via a thermal decomposition process. The CeO₂–ZnO nanocomposites with various CeO₂ quantities of 0–5 mol% characterized the structure, morphology, and optical characteristics using XRD, FT–IR, SEM, UV–Vis spectroscopy, and PL techniques. The phase fraction, lattice constants, and defects were determined by the calculation from the XRD result. The 5 mol% CeO₂–added ZnO sample exhibits the highest polar surface. SEM analysis revealed the presence of ZnO nanorods and CeO₂ nanoparticles. The composites principally featured ZnO with the spontaneous incorporation of CeO₂ nanoparticles. The bandgap was modified as CeO₂ content, showing 3.37 eV for ZnO and 3.31 eV for 5 mol% CeO₂ incorporation. Photoluminescence (PL) analysis demonstrated the Zn, Ce, and O defects and transformation of zinc interstitial (Zn_i) to Zn regular site (Zn_Zn). The photocatalytic degradation of Methylene Blue (MB) under visible light irradiation exhibited a superior efficiency than the single catalyst, determining the influence of charge transfer between the composite interfaces in combination with the sublevel energy of both Ce³⁺ and oxygen vacancy (V_o) being the center of electron trapping. This research points out the characteristics and the performance of thermal decomposition–processed CeO₂–ZnO composites in the photo-induced technology. The charge transfers were discussed, associating with the structural constants, emissive spectra, and sublevel energy.

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Transition metal silicate hydroxides (NFSO) have shown to be stable catalysts for electrocatalytic oxygen evolution reaction (OER) in alkaline environments. However, their catalytic activity is not satisfactory. In this work, we report the high OER performance of amorphous Ni-Fe-Si-B-O (NFSO-B_x) nanosheets catalyst synthesized by a simple coprecipitation method. Compared to traditional NFSO, the incorporation of B changes the electronic structure of NFSO and significantly enhances its activity. The optimum sample NFSO-B₁ exhibits an overpotential of 255 mV at 10 mA cm^− 2, which is 69 mV lower than that of undoped NFSO, and it is durable against 24 h of chronopotentiometry test and 1000 CV cycles. More importantly, the NFSO-B₁ catalyst outperforms NiFe-LDH and the benchmark commercial RuO₂ catalysts in OER activity, demonstrating great potential for commercial application.

Electromigration (EM) failure in solder joints is a persistent reliability concern, especially in advanced electronic packaging structures. In this study, we conducted an EM experiment on solder joints with asymmetric under-bump-metallization (UBM) thicknesses. Open failure occurred at the solder joint with no current crowding effect but the highest atomic flux of EM, which is related to Sn grain orientation. Our work tries to reveal a counteracting effect of Sn grain orientation on current crowding and the essential reason for the EM failure mechanism of solder joints.

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To achieve high-quality sputtered amorphous silicon (a-Si) thin films with low argon (Ar) working gas atom content and high film density, the effects of (:{P}_{Ar}{D}_{TS}) on Ar gas content and film density is investigated. Here, (:{P}_{Ar}) is Ar working pressure and (:{D}_{TS}) is target-to-substrate. The findings from this work indicate that the Ar gas content in the films primarily arises from highly energetic reflected Ar ions that bombard growing a-Si thin films at low (:{P}_{Ar}{D}_{TS}:) values (< 50 Pa·mm). As (:{P}_{Ar}{D}_{TS}) increases, a monotonic decrease in film density is observed. This results well correlates with the declining average energy of sputtered silicon atoms reaching the substrate. Optimal conditions for fabricating sputtered a-Si thin films with both low Ar content and high film density were identified within the (:{P}_{Ar}{D}_{TS}) range of 30–40 Pa·mm. This research could provide valuable insights for researchers seeking to optimize the balance between low working gas content and high film density in sputtered thin films.

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In recent years, there has been increasing interest in developing solutions to maintain human body temperature in extremely cold environments. Wearable electrically heated fabrics have been extensively researched, however, their complex preparation processes and associated environmental concerns hindered their widespread adoption. To address these challenges, this study focuses on develop a novel materials, which suitable for wearable applications with the low energy consumption and environmentally friendly. In this work, a simple and eco-friendly preparation method was proposed. The viscose-based carbon fabric (VCF) was prepared using viscose fabric as the raw material by means of high-temperature carbonization. The VCF exhibits excellent flexible, good electrical conductivity and remarkable photothermal conversion properties as well. VCF can absorb sunlight for heating and also has electric heating properties. Due to its outstanding flexible and thermal capability, the VCF was applied to heat human body under solar radiation; furthermore, the high electric heating efficiency makes it suitable for a wide range of applications, including indoor heating or de-icing treatment. With its strong potential for wearable applications, viscose-based carbon fabric presents a promising, energy-efficient solution for all-day personal thermal management. This research offers a broad and sustainable approach to developing advanced thermal management fabrics for diverse environmental conditions.

Being the fundamental process of advanced back-end-of-line (BEOL) interconnects, the performance of copper (Cu) electrochemical plating (ECP) affects the resistivity of metal lines and plays a crucial role in RC delay and reliability concerns. A great deal of attention has been focused on reducing the Cu voids, but few reports concentrate on the initial period of ECP, especially when the wafer is immersed in the electrolyte. By optimizing the wafer immersion conditions, I achieved a defect image quantification reduction from a maximum of 88ea to a minimum of 0ea, indicating that a void-free Cu line was realized through a standard plating process, thanks to the reduced surface potential difference during the initial phase. As we develop advanced technology nodes such as below the 7 nm technology node, the higher requirement for the RC delay and reliability performance, this work has good potential applications below the 7 nm technology node, because it provides a promising solution to reduce Cu line voids and can be beneficial to alleviate the RC delay and enhance the reliability in back end of line (BEOL) interconnection.

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High-performance chemresistive gas sensors operating at low or room temperatures are of great potential for practical applications. In this work, the oxygen vacancies-rich BiFeO_3 − x microflowers were synthesized using a facile solvothermal route. The characterized results showed that BiFeO_3 − x was assembled with nanosheets, and displayed a diameter of around 1 μm. The as-fabricated BiFeO_3 − x gas sensor exhibited fine sensing properties towards 0.5-5 ppm NO₂ under ~ 23 ^oC, including a response of 2.92 to 5 ppm NO₂, and it also maintained a response of 1.05 towards 50 ppb NO₂. The gas sensor demonstrated a theoretical limit of detection as low as 273 ppb, rapid response/recovery speed (22/69 s), good selectivity, and repeatability. The improved NO₂ sensing mechanism of enriched oxygen vacancies-BiFeO_3 − x was investigated regarding its micro-nano structure and abundant oxygen species.

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In the last decade, interest in solution-processed transparent oxide semiconductors has been increasing. Specifically, indium oxide (In₂O₃) films have been researched due to their processability using aqueous solutions without organic additives. However, the film quality of as-deposited layers might be suboptimal, which requires some type of post-deposition treatment. In this work, the effect of the treatment by a focused plasma (FP) under both N₂ (FP-N) and N₂:H₂ (FP-H) gases on In₂O₃ thin-film transistors (TFTs) is explored. The In₂O₃ TFTs with optimized device performance were fabricated using a volatile nitrate precursor at an annealing temperature of 250 °C. The FP-N In₂O₃ devices achieved saturation mobility (µ_sat) of 3.83 ± 0.14 cm²/Vs, and the threshold voltage was about 3 V. The FP-H devices with a µ_sat of 2.56 ± 0.15 cm²/Vs, on/off current ratio of 4.3 × 10⁶, exhibited stable electrical characteristics with improved gate bias stress stability and time-dependent environmental stability. These results demonstrate that FP treatment of solution processed In₂O₃ semiconductors effectively enhances carrier transport performance and improves bias stability.

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Han-Lin Zhao et al., Indium oxide semiconductors prepared based on solution-processes have many advantages, such as the ability to be prepared at low temperatures, but the performance of the prepared devices is poor. This work has shown that the performance of the devices can be improved by subjecting the devices to an oxygen-free focused plasma treatment for different gas

Alloys based on SnTe have been widely studied for their eco-friendly characteristics and good electrical performance in the high-temperature range above 600 K. In this study, SnTe-InTe solid solution alloy compositions of Sn_1 − xIn_xTe (x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0) were investigated for their phase formation behavior and thermoelectric properties. A single cubic SnTe phase was formed in x ≤ 0.4 samples, while x = 0.6 and 0.8 samples formed multi-phase with a tetragonal InTe phase. The carrier mobility gradually decreased with increasing x in the single cubic phase region (x = 0-0.4), and a drastic reduction of 58% for x = 0.2 and 82% for x = 0.4, causing S and σ to decrease simultaneously compared to that of the pristine SnTe. Thus, the power factor gradually reduced to 0.06 mW/mK² for x = 0.4 compared to 1.57 mW/mK² for the pristine sample, as confirmed by the weighted mobility reduction behavior. The lattice thermal conductivity showed a gradual decrease in the simple cubic phase region, owing to the additional point defects formed by In substitution of Sn sites. Consequently, zT gradually decreased from 0.31 for the pristine to 0.02 for x = 0.4 sample due to the degradation of carrier transport properties, specifically Hall mobility, outweighing the total thermal conductivity reduction. The maximum zT value of 0.50 at 750 K was observed for InTe (x = 1.0). Additional analysis using the single-parabolic-band model indicated that zT enhancement through carrier concentration optimization was not feasible for the alloy samples.

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Here, we report on the two-dimensional (2D) (PbI₂)_0.5(BiI₃)_0.5 mixed halide memristor, which exhibits nonlinear conductance that surpasses the properties of the simple combination of PbI₂ and BiI₃ binaries. This 2D system is phase-separated into Bi-rich and Bi-poor nanoscale domains rather than forming a single homogeneous phase. Phase boundaries, predominantly featuring iodine vacancies or stacking faults, induce a novel memristive behavior along the c-axis, driven by ion transport perpendicular to the layered structure, making it promising for resistive switching memory (RRAM) applications. In-situ biasing transmission electron microscopy (TEM) reveals the formation of iodine filaments under sweep bias, with ion migration occurring mainly through phase boundaries in the out-of-plane direction. Direct observation of reversible filament formation in this phase-separated iodide system provides new insights into defect-mediated ion migration, resulting in nonlinear resistive switching, with potential applications in neuromorphic computing. The ability to track heavy anions like iodine in the halide memristor provides valuable insights into the similar correlation mechanisms between ion migration and defects in oxide or sulfide-based memristors. This capability could shed light on how defects influence ion transport in a broader range of materials, enhancing the development of resistive switching devices.

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