Silicon最新文献

In this study, we optimized the utilization of Tunisian Aquitanian deposits from the Fortuna Formation for ceramic pigment synthesis. Samples were collected from Jebel Menchar in the Bouficha region, situated in the Northern Atlas of Tunisia. Characterized by a predominant composition of quartz and K-feldspar, Aquitanian sands were extensively investigated using X-ray diffraction (XRD), X-ray fluorescence (XRF), infrared analyses, Scanning Electron Microscopy coupled with energy dispersive spectroscopy (SEM/EDS), thermogravimetric analysis (TGA), and differential thermal analysis (DTA), serving as primary materials in the laboratory-scale production of Co-willemite and Co-olivine blue pigments. The resulting pigments demonstrated notable stability and crystalline structure, particularly when exposed to a calcination temperature of 1100 °C. The confirmation of pigment phase formation was established through XRD and FTIR analysis. Furthermore, UV–visible measurements indicated significant absorbance in the UV region. These pigments displayed semiconducting gap energies, implying potential applications in semiconducting materials or devices. Their application on both transparent and opaque glazes showcased interesting blue coloration, substantiated by measurements in the CIEL color space. Comparative analysis with commercially available equivalents revealed comparable coloring performance, suggesting the potential viability of silica sand as a source for synthesizing blue pigments with properties similar to those of established commercial alternatives. Ultimately, this research supports the use of local Aquitanian sand as a sustainable and effective raw material for the production of ceramic pigments.

The solidification process of industrial silicon (Si) is influenced by impurities, which significantly affect the selectivity and activity of silicone monomer synthesis. This study utilized the molecular interaction volume model (MIVM), factory data, and industrial silicon samples to explore the effects of different Fe concentrations on typical impurity phases in industrial silicon during actual production. At a Fe concentration of 3300 ppmw, Si₇Al₈Fe₅ and Si₂Al₃Fe phases appeared. At a Fe concentration of 3400 ppmw, the Si₂Al₃Fe phase disappeared. The FeSi₂(Al), Si₈Al₆Fe₄Ca, and FeTiSi₂ phases were consistently present in industrial silicon. The MIVM model prediction indicated that the activity of Ca was negatively correlated with Fe concentration, while the activities of Ti and aluminum (Al) were positively correlated with iron concentration, which was consistent with the actual production process. This study elucidated the influence of Fe concentration on typical impurity phases in industrial silicon and provided a theoretical and technical basis for impurity regulation in the synthesis of organic silicon monomers.

The demand for terahertz (THz) wave absorbers with broadband absorption has increased because of their informal configuration and superior performance for a variety of potential applications. In this study, a three-dimensional (3D) heterostructure is investigated, and broadband absorption is observed in the 1.0 to 20.0 THz range through stacking Lego-like multiple layers, which support unique electronic properties with potential applications in quantum technologies and nanoelectronics. The absorber's average absorption was 97.8%, and its highest absorption is 99.6%, occurred in the 7.75 THz to 19.85 THz spectral region with overall absorption greater than 95%. The high absorption is caused by strong plasmonic resonances between multiple layers such as gold (Au) and graphene (G) layers. To improve overall absorption, the silica (SiO₂) and silicon (Si) layers control the plasmonic resonance of the G layers. The polymethyl methacrylate (PMMA) layer serves as a protective layer and adds absorbency. The photonic responses are inspected, including how the light interacts with bilayers that can modify their responses, light absorption, polarization, and electromagnetic field distribution. The final results explored the enhancement in optical performance by using various applications such as sensing, imaging, and photodetection and establishing generic and systematic methodologies for design directing of metamaterial absorbers with outstanding broadband absorption.

Organic rice cultivation relies on natural inputs for crop growth and protection. Natural silica offers a solution for managing the pest population and also enhances the plant growth, in addition to natural enemies’ attraction. Field experiments were conducted over two seasons with sole and combined application of natural silicon granules in soil (25 kg/acre) and dust spraying (1%) at 15, 30 and 45 days after transplanting (DAT) to manage yellow stem borer populations. Combined application of silicon granules along with dust at 15, 30 and 45 DAT (SA3/FA) significantly enhanced the total phenols (0.34 g pyrocatechol equivalents/100 g), peroxidase (0.54 ΔA/min/g), polyphenol oxidase (0.20 ΔA/min/g) and Phenylalanine ammonia lyase (0.87 ΔA/min/g). Silicon deposition in plant tissues also caused abrasions in the mandibles of YSB larvae and increased natural enemies (Telenomus sp., Trichogramma sp., dragonflies, damselflies and spiders) by 60–86.36% in winter and 40.21–81.57% in summer. These direct and indirect defense mechanisms worked together and resulted in 82.34% and 82.37% reduction in YSB damage for both the seasons. The study highlights that SA3/FA treatment effectively managed YSB and increased grain yield by 39.75% in winter and 42.50% in summer under organic rice production.

This article presents a detailed study of the admittance and dielectric characteristics of Al/MgO/p-Si device. The admittance (Y) measurements including both conductance (G) and capacitance (C) components of the device were performed in the frequency range of 5 kHz-3 MHz. Interface traps affecting the electrical properties of the device were determined from the measured C and G data at various frequencies using different methods such as the high-low frequency (C_HF-C_LF) capacitance and conductance. Furthermore, the dielectric parameters including ε', ε" and tanδ of the device were calculated using these measurement data. The high values ​​ of ε', ε" and tanδ were attributed to the presence of space charge polarization. The increase of ac conductivity (σ_ac) with frequency is related to the increased mobility of electric charge carriers. The experimental results indicate that the fabricated Al/MgO/p-Si structure exhibits characteristics suitable for application as an energy storage component in electronic systems.

The non-stoichiometric solid solution Bi₄Si_x/2Sn_x/2V_2-xO_11-3x/4 (where 0.1 ≤ x ≤ 0.5), referred to as BiSiSnVOx, was synthesized via the conventional solid-state reaction method. The resulting materials were subjected to comprehensive structural and microstructural characterization using X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy combined with energy-dispersive X-ray spectroscopy. X-ray diffraction analyses performed at room temperature and as a function of temperature confirmed the presence of three crystalline phases: α, β, and γ. These results were confirmed by Raman and infrared spectroscopic data. Scanning electron microscopy images revealed a dense microstructure with well-defined grains. Furthermore, the optical band gap of BiSiSnVOx was found to decrease from 2.08 electron volts (for x = 0.1) to 1.91 electron volts (for x = 0.4), indicating enhanced absorption in the visible range and promising potential in photocatalytic applications.

Dual-material double-gate tunnel field effect transistor (DMDG TFET) is a promising candidate for low-power, high-speed electronics due to enhanced electrostatic control and superior switching characteristics. Integrating a pocket region between the source and channel—doped oppositely to the source—further improves tunneling efficiency by modulating the electric field at the tunneling junction. This combined architecture, termed the DMDG source-pocket TFET (DMDG-SP TFET), achieves higher ON current and reduced subthreshold swing compared to conventional TFETs. Previous DMDG-SP TFET designs used heterojunction structures and heterogeneous gate dielectrics, composed of two stacked insulators to enhance tunneling modulation and gate control. However, such hetero-structures increase fabrication complexity and may degrade reliability due to material incompatibility. This work proposes a novel DMDG-SP TFET design that combines a dual-material double-gate and a source-pocket in a homojunction silicon-based structure, using a single homogeneous high-k gate dielectric. 2-D TCAD simulations performed in Silvaco ATLAS demonstrate that the inclusion of the source-pocket improves ON current by 6.7 × and reduces subthreshold swing by 1.7 × compared to pocket-less devices. Dual-material gates boost ON current by 45% and improve ON/OFF ratio by 59% compared to single-material gates. Detailed simulations analyze the effects of gate work functions, dielectric constant, doping profiles and lengths of different regions. The optimized device achieves an ON current of 3.16 × 10⁻⁴ A/µm, OFF current of 1.54 × 10⁻¹⁷ A/µm, ON/OFF ratio of 2.05 × 10¹³, and point subthreshold swing of 6.29 mV/decade. These findings offer critical insights for designing manufacturable, high-performance TFETs for next-generation low-power integrated circuits.

This study created a unique (Polyvinyl alcohol) PVA composite material reinforced with biosilica from barnyard millet husks, demonstrating the composite's potential to replace synthetic materials, including packaging, infrastructure, automotive, aerospace, and marine. The biosilica is produced by pyrolyzing barnyard millet husk at 800ºC, and PVA is used as a resin. Of the examined specimens, PB3 exhibited the highest tensile strength at 64 MPa, a 36.2% gain; the highest tensile modulus at 1.9 GPa, a 58.3% increase; and the highest tear strength at 32 N/mm, a 39.1% improvement over the base specimen, P. Nevertheless, PB3 also showed a decrease in elongation at break to 104%, suggesting that the larger biosilica content had rendered it more brittle. With values of 14.6 mm against S. aureus and 15.5 mm against E. coli, PB4 showed the highest inhibition zones with regard to antibacterial capabilities. This is consistent with the antimicrobial effect of biosilica, which breaks bacterial cell membranes. For PB4, the water contact angle was 69°, showing a high degree of hydrophobicity. Additionally, the composite PB4 exhibits barrier qualities such as oxygen permeability and water vapour transmission rate (WVTR) of 2.8 cm³•mm/m²•day•kPa and 4.6 g/m²/day, respectively. PVA's hydroxyl groups form hydrogen bonds with biosilica. This leads to increased interfacial adhesion, matrix densification, and reduced free volume, which limits diffusion channels.Furthermore, at 0.66 W/mK, PB4 had the lowest thermal conductivity. While biosilica was well-dispersed in PB3, offering better mechanical reinforcement, PB4 showed some particle agglomeration, which, while detrimental to mechanical properties, enhanced its barrier effects, contributing to its superior thermal, antimicrobial, and water-resistant properties. These findings were further supported by the SEM analysis.

This study investigates the DC and RF characteristics of Quadruple Metal (QM) Inversion Mode (IM) and Junctionless (JL) Cylindrical Gate-All-Around (CGAA) Silicon Nanowire (SiNW) MOSFETs with a 3 nm gate length, using Silvaco ATLAS 3D TCAD and the Non-Equilibrium Green Function (NEGF) method with self-consistent Schrödinger-Poisson solutions. Key parameters analyzed include drain current (I_D), transconductance (g_m), transconductance generation factor (TGF), cut-off frequency (f_T), frequency transconductance product (FTP), transit time (τ), and total resistance (R_SD+CH) for a SiNW with a 3 nm diameter and 0.8 nm gate oxide. The impact of QM gate work function engineering is compared between IMQM and JLQM devices. JL devices are optimized for equivalent I_ON and V_TH as IM devices, achieving ~ 246.96 times and ~ 86.32 times lower I_OFF, respectively. QM gate variation reduces DIBL in both devices, with JL SiNW showing superior performance: DIBL (~ 75.42 mV/V), near-ideal subthreshold swing (~ 60 mV/dec), and high I_ON/I_OFF (~ 1.92 × 10¹¹), outperforming IM devices in SS, DIBL, I_ON/I_OFF, g_m, TGF, fT, τ, FTP, and R_SD+CH.

This study investigated the dielectric and electrical features of Au/ZnO/p-InP (MOS) device over the 10 Hz to 1 MHz frequency range under dc bias voltages from 0.75 to 1.75 V in the periodic increment of 0.25 V, all measured at room temperature. Impedance spectroscopy showed that the real component of the impedance (Z′) diminishes as the frequency and bias increase, while the imaginary component (Z″) presents a single relaxation peak that shifts with bias. Cole–Cole plots were used to extract equivalent circuit elements, revealing that parallel resistance (R_p) decreases with bias, while series resistance (R_s) and capacitance (C_p) remain nearly constant. The dielectric constant (ε') and dielectric loss (ε''), which are the real and imaginary parts of the complex dielectric permittivity, were measured under the same conditions as the impedance measurements. The findings demonstrate that the values of ε' and ε'' exhibit a rapid decline as the frequency increases up to 100 kHz, beyond which they remain nearly stable at higher frequencies. This indicates a reduced polarization response due to limitations in dipolar relaxation. ac conductivity is nearly constant at low frequencies but increases linearly above 10 kHz, suggesting hopping conduction. These findings demonstrate that the characteristics of the fabricated device are strongly affected by variations in frequency and applied voltage and thus it can be used as an electronic circuit component.