Hasil untuk "Plasma engineering. Applied plasma dynamics"

Khurrem Shehzad, Jun Wang, Muhammad Arshad et al.

S. K. Dhiman, Sachin Kumar

Jonas Giesekus, Anton Pletzer, Florian Beckfeld et al.

Precise control of ion energy distribution functions (IEDFs) is crucial for selectivity as well as control over sputter rate and substrate damage in nanoscale plasma processes. In this work, a low frequency (100 kHz) tailored pulse-wave-shaped bias voltage waveform is applied to the substrate electrode of an inductively coupled plasma (ICP) and its effects on the IEDF, electron density, electron dynamics and the etch rates of silicon dioxide as well as amorphous silicon are investigated in a commercial 200 mm reactive ion etching reactor. While the tailored waveform substrate bias hardly affects the electron density above the substrate and the spatio-temporally resolved electron power absorption dynamics, it is found to affect the ion flux to the substrate at high ICP source powers. Monoenergetic IEDFs with a full width at half maximum below 10 eV are realized with mean ion energies ranging from 20 eV to 100 eV in both argon and SF6. Using a modified voltage allows generating two independently controllable peaks in the IEDF. The monoenergetic IEDFs are used to determine the Ar ion sputter threshold energies of amorphous silicon and silicon dioxide to be 23 eV and 37 eV, respectively. This enables selective etching of these two materials by Ar ion sputtering based on tailoring the IEDF to ensure that all incident ions are within this narrow ion energy selectivity window.

Dai-En Li, Che-Hsin Lin

This study presents a systematic investigation into the effect of charge relaxation properties on the discharge behavior of a pin-to-water dielectric barrier discharge (DBD) reactor. Potassium chloride (KCl) solutions with concentrations ranging from 10−6 to 100 mol/L were employed to systematically manipulate the charge relaxation time (τe) of the liquid electrode. Our findings demonstrate that the discharge behavior critically depends on the ratio of τe to the characteristic timescale (tc) of the plasma–liquid system, derived from the applied voltage frequency. When τe/tc1, charge transfer becomes significantly slower than voltage switching, leading to substantial charge accumulation and elliptical Q–V diagram deformation due to charge residual. Furthermore, the non-uniform surface charge distribution, coupled with inherent plasma propagation asymmetry, results in stepped Q–V curves and several individual filamentary discharges during the rising period of applied voltage. These results provide fundamental insights into designing and controlling DBDs with resistive liquid electrodes for diverse applications.

Haopeng Wang, Liping Yang, Stefaan Poedts et al.

Time-evolving magnetohydrodynamic (MHD) coronal modeling, driven by a series of time-dependent photospheric magnetograms, represents a new generation of coronal simulations. This approach offers more realistic results than traditional steady coronal models constrained by a static magnetogram. However, its practical application is significantly limited by the low computational efficiency and poor numerical stability in solving low- β issues common in coronal simulations. To address this, we propose an extended magnetic field decomposition strategy and successfully implement it in an implicit MHD coronal model. The traditional decomposition strategies split the magnetic field into a time-invariant potential field and a time-dependent component B _1 . This works well for quasi-steady-state coronal simulations where ∣ B _1 ∣ is typically small. However, when the inner-boundary magnetic field evolves, ∣ B _1 ∣ can grow significantly, and its discretization errors often lead to nonphysical negative thermal pressure, ultimately causing the simulation to crash. In the extended magnetic field decomposition strategy, we split the magnetic field into a temporally piecewise-constant field and a time-varying component, B _1 . This effectively keeps ∣ B _1 ∣ consistently small throughout the simulations and performs well in solving time-evolving low- β issues, thereby outperforming traditional methods. We incorporate this improved strategy into our implicit MHD coronal model and apply it to simulate the evolution of coronal structures within 0.1 au over two solar-maximum Carrington rotations. The results show that this coronal model effectively captures observational features and performs more than 80 times faster than real-time evolutions using only 192 CPU cores, making it well suited for practical applications in simulating the time-evolving corona.

Dalia Diab, Tahreem Noor Khan, Raya Saad Almjnoni

In the competitive landscape of the food and beverage industry, brand equity and consumer response are crucial aspects influencing a café’s success. This study investigates the impact of brand equity dimensions (brand awareness, brand association, brand loyalty, and perceived quality) on consumer response (purchase intention and brand preference) in the Saudi Arabian café industry. Using a quantitative approach, data were collected from 300 university students in Hail City through an electronic survey. The hypotheses were tested using multiple linear regression analysis in SPSS version 25.0. The findings revealed that brand loyalty and brand association significantly and positively influence overall brand equity, while perceived quality and brand awareness did not demonstrate a significant impact. A positive and significant correlation was also observed between overall brand equity and consumer response.

Sashka Alexandrova, Anna Szekeres, Evgenia Valcheva

Since the early days of silicon manufacturing, hydrogen gas treatment has been used to control the defect concentrations. Its beneficial effect can be enhanced using hydrogen plasma as a source of active atomic hydrogen. Hydrogen plasma modification of c-Si surface can be challenging because the plasma can induce precursors of defect centers that can persist at the interface and/or grown oxide after subsequent thermal oxidation. In the present study, we investigate nanoscale silicon dioxides with thicknesses in the range of 6–22 nm grown at low temperature (850 °C) in dry oxygen on radio frequency (RF) hydrogen plasma-treated silicon surface. The properties of these oxides are compared to oxides grown following standard Radio Corporation of America (RCA) Si technology. Electroreflectance measurements reveal better interface quality with enhanced electron mobility and lowered oxidation-induced stress levels when the oxides are grown on H-plasma modified c-Si substrates. These results are in good accordance with the reduced defect concentration established from the analysis of the current–voltage (<i>I</i>-<i>V</i>) and multifrequency capacitance–voltage (<i>C</i>-<i>V</i>) characteristics of metal-oxide-semiconductor (MOS) capacitors incorporating the Si-SiO₂ structures. The study proves the potential of hydrogen plasma treatment of Si prior to oxidation for various Si-based applications.

Mustafa Faisal Ghlaim, Asmaa Miran Hussein, Mustafa Fakhir Hussein

Developing new green energy technologies is one of the significant solutions to meet the growing energy demand worldwide. However, due to ongoing conflicts, the rapid growth of green hydrogen energy technologies encounters various technical barriers, such as the declining adoption of wind and solar energy in several Middle Eastern countries, including Iraq, Syria, Lebanon, and Yemen. This study elucidates the importance of green hydrogen energy globally. It highlights the shift toward sustainability based on insights from recent research conducted between 2024 and 2025 and global energy trends aimed at enhancing environmental and energy security by 2050.

Waseem Razzaq, Asim Zafar, Naif Almusallam et al.

This work reveals the novel types of exact solitons for the coupled (2 + 1)-dimensional Painlevé’s–Burgers model in the sense of novel fractional derivative. To gain the different kinds of exact solitons, we utilized the modified extended direct algebraic technique. Dynamical behaviors of the achieved results are explained with the help of 2-dimensional, 3-dimensional, and contour plots. Furthermore, to confirm the stability of the concerned model and the obtained solutions, we utilized the stability and modulation instability analysis. The achieved results are newer than the existing results of the concerned equation. The gained results are useful in many areas, including fluid dynamics, nonlinear wave propagation, turbulence and chaos, plasma physics, traffic flow, weather forecasting, ocean engineering, aerodynamics, etc. At the end, it is concluded that the utilized technique is also helpful and applicable for the other nonlinear fractional equations in applied science and engineering.

Pooja Sithrubi Gnanasambanthan, M. Gnana Priya

Mental health challenges demand innovative, non-invasive interventions to reduce stress and enhance emotional stability. Music has long served as a therapeutic medium; however, existing approaches often rely on generic playlists that lack personalization and adaptability to an individual’s psychological state. This paper presents a novel framework that combines webcam-based facial expression analysis with questionnaire-based self-reports to achieve robust emotion detection. The proposed system employs deep learning models to extract emotional cues from visual data, while structured self-assessments provide subjective validation of user states. A fusion mechanism integrates both modalities to enhance the accuracy and reliability of emotion recognition. Based on the detected emotional profile, personalized music recommendations are generated and visualized through interactive Power BI dashboards. This multimodal, AI-driven approach bridges traditional music therapy with modern data analytics, enabling adaptive, accessible, and user-centric mental health support. The experimental results highlight the potential of this method to enhance emotional well-being, alleviate stress, and increase access to personalized therapy.

Mujahid Iqbal, Waqas Ali Faridi, Huda Daefallh Alrashdi et al.

Abstract In this paper, the nonlinear coupled system of partial differential equations named the Wu–Zhang system investigated by applying the new auxiliary equation method. The Wu–Zhang system help us to investigate the various nonlinear wave propagation phenomena physically including the width and amplitude of solitons, physically form of shock, traveling and solitary wave structures in fiber optics, fluid dynamics, plasma physics, nonlinear optics, these nonlinear wave equations play significant role in these phenomenas. In this regard, the dispersive long wave is described by the Wu–Zhang system, from which a number of solitons and solitary wave structure are formally extracted as an accomplishment. On the basis of the computational program Mathematica, soliton and many other solitary wave results have been obtained with the ability to use an analytical approach. Consequently, various solutions in solitons and solitary waves are generated in rational, trigonometric, and hyperbolic functions and displayed within contour, two–dimension and three–dimension plotting by using the numerical simulation. The soliton solutions are obtained including bright and dark solitons, anti–kink wave solitons, peakon bright and dark solitons, kink wave soliton, periodic wave solitons, solitary wave structure, and other mixed solitons. In order to comprehend the significance of investigating various nonlinear wave phenomena in engineering and science, including soliton theory, nonlinear optics, fluid mechanics, material energy, water wave mechanics, mathematical physics, signal transmission, and optical fibers, all research outcomes are required. With precise analytical results, shed light that the applied approach to be more powerful, dependable, and accurate.

Sonia Ceron, David Barba, Miguel A. Dominguez

In this work, silver nanoparticles (AgNPs) used in conductive inks were synthesized for implementation in printable and flexible electronics. The nanoparticles were obtained using silver nitrate as a precursor agent, sodium citrate as a reductive/protective agent and sodium borohydride as a reductive, whose concentrations were varied for optimization. The optical absorption, morphology, size-distribution, crystallinity and stability over time of the processed nanoparticles were determined upon the content of the chemical contents. The AgNPs-based inks were then tested as conductive wires drawn on different common flexible substrates to measure their electrical characteristics and demonstrate their relevance in printable electronics.

A. A. Molavi Choobini, M. Shahmansouri

The detailed theoretical and numerical investigation of hybrid laser plasma RF accelerators, elucidating the mechanisms governing transverse beam dynamics, betatron polarization, and radiation reaction in ultra-relativistic electron bunches is presented. This framework combines analytical models of spatiotemporal plasma wakefield modulation, phase-dependent RF-driven oscillations, and quantum-corrected Landau Lifshitz radiation reaction with fully self-consistent 3D particle in cell simulations using EPOCH. The results demonstrate that RF amplitude, frequency, and phase enable precise control over transverse focusing strengths, betatron oscillation amplitudes, and polarization states. Resonant alignment between RF fields and natural betatron frequencies amplifies transverse excursions while damping parasitic oscillations through enhanced focusing gradients and radiation reaction, yielding reductions in emittance and mitigation of synchrotron-like energy losses. Stability maps and 3D force landscapes reveal strong phase sensitivity, where initial conditions and RF component ratios govern the temporal evolution of betatron amplitudes, and longitudinal field gradients modulate γ growth rates. These findings provide a comprehensive picture of nonlinear, resonant, and damping phenomena in hybrid laser plasma RF systems, highlighting the full spectrum of controllable transverse, longitudinal, and polarization dynamics in ultra relativistic electron beams.

Y. Gui, Eve Lanham, M. J. Kushner

The improved properties of core–shell nanoparticles (CSNPs) over homogeneous nanoparticles (NPs) have expanded and diversified the applications of these nanomaterials. However, controlling the properties of CSNPs can be a challenging task. Low temperature plasmas have proven to be an effective method of producing NPs with uniform size and morphology, and high yield. That said, NP transport and growth dynamics are sensitive to LTP properties. We report on a computational investigation of the evolution of Ge–Si CSNP properties as a function of operating conditions through the modeling of a flowing, two-zone inductively coupled plasma (ICP) reactor. Ar/GeH4 and Ar/SiH4 gas mixtures were supplied to separate plasma zones at a pressure of 1 Torr to promote growth of Ge cores and Si shells. The negatively charged CSNPs are trapped electrostatically in the vicinity of the antennas where the plasma is generated and where the majority of particle growth occurs. Particles that grow to a critical size are then de-trapped by fluid drag due to neutral gas flow. A two-dimensional hybrid plasma model coupled with a three-dimensional kinetic NP transport model were utilized to resolve plasma chemistry and NP growth processes that take place on distinct timescales. The trends in CSNP properties and trapping mechanisms associated with flow rate, applied ICP power and inlet precursor fraction are discussed. While the spatial distribution of plasma produced radical species can have significant impact on the NP growth process, the NP transport dynamics are what ultimately dictates the growth environment that is unique to each particle and so determines their final dimension and composition. The key to optimizing reactor conditions involves controlling the spatial density of growth species and plasma profile as a means to tailor particle trapping dynamics suitable to produce CSNPs for a specific application.

E. T. Semaha, G. Miloshevsky

The dynamics of laser-produced plasma plume expansion involves complex interactions between the ablated material and ambient air. This study investigates and compares the performance of three OpenFOAM solvers, namely twoPhaseEulerFoam (tPEF), rhoCentralFoam (rCF), and sonicFoam (sF) using an identical initial setup of geometry and parameters. The primary objective of this study is to affirm the applicability and reliability of the tPEF solver in modeling the laser-produced plasmas for multispecies cases. The focus is on the evaluating the tPEF solver’s ability to simulate plasma plume dynamics under atmospheric air pressure. Propagation of plasma shockwave, mesh generation, initial and boundary conditions, and hydrodynamics of single- and multi-phase equations are analyzed. Critical flow variables, such as pressure, velocity, temperature, and density, were monitored spatially and temporally to evaluate the solver performance. The simulation results demonstrate that tPEF produces stable and reliable results that align with physical expectations and previously published data. It was found to be particularly effective in capturing the plume’s hydrodynamic features, including multi-species behavior and interaction with the ambient environment. The findings affirm applicability of tPEF for modeling laser-induced plasma plumes, especially in capturing complex fluid dynamics and species evolution. This study will provide computational foundations essential for specific engineering applications involving pulsed laser ablation of multi-component materials.

S. Abarzhi

Kashifa Basheer, Atef F. Hashem, Muhammad Arshad et al.

Seongsik Jang, Hyun Zun Lee, M. U. Lee

Transformer coupled plasma (TCP) sources are widely used in etching processes due to their ability to generate low-pressure, highly uniform, and high-density plasma. However, byproducts generated during etching accumulate on chamber walls, degrading plasma reproducibility and increasing both the frequency and duration of cleaning steps, ultimately reducing process throughput. To address this, plasma-based dry cleaning is commonly employed. In conventional dry cleaning processes, however, ion kinetic energies and incidence angles are not actively controlled, which limits further improvement in cleaning performance. In this study, we propose a method to enhance cleaning efficiency in TCP chambers by modulating charged particle dynamics via Lorentz force control through externally applied magnetic fields. Fluid plasma simulations were conducted under various magnetic field configurations to identify efficient field strengths and geometric distributions that enhance ion kinetic energy flux and guide ion incidence angles into the optimal range for wall cleaning. Specifically, the simulations incorporated Maxwell coils installed along the chamber sidewalls to implement realistic magnetic field distributions and verify their effectiveness in controlling ion flux to the chamber walls. Cleaning performance was assessed based on the ion kinetic energy flux and average ion incidence angle on the wall. The results confirm that magnetic field-based control of ion dynamics is an effective strategy for improving the efficiency of plasma-based dry cleaning processes.

Yue Lin, Zhao Xue, Wen-An Huang et al.

Md. Abdul Aziz

The Kadomtsev–Petviashvili (KP) equation and the Bogoyavlensky–Konopelchenko (BK) equation are fundamental models in the study of nonlinear wave dynamics, describing the evolution of weakly dispersive, quasi‐two‐dimensional (2D) wave phenomena in integrable systems. In this article, we introduce a novel analytical technique, the G′G′+G+A ‐expansion method, designed to derive exact, closed‐form solutions to these equations with increased efficiency and generality. The KP equation, which describes the propagation of surface waves in shallow water or plasma waves in a cylindrical geometry, and the BK equation, a higher‐dimensional generalization of the KP equation, are both critical in understanding soliton dynamics and wave interactions in nonlinear media. By exploiting the structure of the equations and the interplay between various terms, the method enables the construction of exact solutions that are difficult to obtain using traditional perturbation or ansatz‐based approaches. We apply this method to derive several classes of solutions to both the KP and BK equations, including multisoliton solutions, complex wave structures, and exact traveling wave solutions. Our results highlight the flexibility of the method in capturing a wide range of solution types, which are highly relevant to real‐world applications, such as wave pattern formation, soliton interactions, and stability analysis in nonlinear systems. Using the proposed expansion method, innovative solutions are derived, including an antibell‐shaped soliton, a kink‐shaped soliton, and a singular periodic solution. These results are presented through three‐dimensional (3D), 2D, and contour plots, offering a clear understanding of their physical properties.