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Electrical characterization and imaging of discharge morphology in a small-scale packed bed dielectric barrier discharge Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-27 Rezvan Hosseini Rad, Volker Brüser, Ronny Brandenburg
Packed bed dielectric barrier discharges (DBDs) exhibit an improved energy efficiency and selectivity in nonthermal plasma based gas conversion. They enable the direct interaction between plasma and catalyst. In this contribution a compact coaxial DBD reactor enabling the end-on imaging of the discharge with and without packed beds is studied. The discharge morphology is correlated with electrical
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Transient striations in an inductively coupled plasma during E-to-H transitions Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-27 Meng-Zhi Gu, Zhi-Cheng Lei, Xuan Zhang, Yi-Kang Pu
Azimuthal transient striations are reported for inductively coupled Ar plasma during E-to-H transition at 200 mTorr. In this transient process, the number of striations increases with time, and striations ultimately disappear when the H mode is reached. An integrated model is developed to investigate the mechanism of this phenomenon. This integrated model incorporates a one-dimensional time-dependent
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Properties and characteristics of the nanosecond discharge developing at the water–air interface: tracking evolution from a diffused streamer to a spark filament Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-26 Garima Arora, Petr Hoffer, Václav Prukner, Petr Bílek, Milan Šimek
The characteristics of nanosecond discharge propagating along the water–air interface in a unique dielectric-barrier discharge (DBD)-like configuration with coplanar electrodes submerged in deionised (DI)/tap water are studied by combining ultrafast imaging and emission spectra with electrical characteristics. Time-resolved images provide a clear signature of streamer channels excited on the water
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Genesis of column sprites: formation mechanisms and optical structures Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-26 R Marskar
Sprite discharges are electrical discharges that initiate from the lower ionosphere during intense lightning storms, manifesting themselves optically as flashes of light that last a few milliseconds. This study unravels sprite initiation mechanisms and evolution into distinctive morphologies like glows and beads, using direct 3D numerical simulations that capture the intricate electrical discharge
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A 3D kinetic Monte Carlo study of streamer discharges in CO2 Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-23 R Marskar
We theoretically study the inception and propagation of positive and negative streamers in CO2 . Our study is done in 3D, using a newly formulated kinetic Monte Carlo discharge model where the electrons are described as drifting and diffusing particles that adhere to the local field approximation. Our emphasis lies on electron attachment and photoionization. For negative streamers we find that dissociative
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Experimental and 2D fluid simulation of a streamer discharge in air over a water surface Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-22 Antoine Herrmann, Joëlle Margot, Ahmad Hamdan
The high reactivity and attractive properties of streamer discharges make them useful in many applications based on plasma-surface interactions. Therefore, understanding the mechanisms governing the propagation of a streamer discharge as well as its properties is an essential task. This paper presents the development and application of a 2D fluid model to the simulation of discharges triggered at the
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The wave mode transition of argon helicon plasma Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-22 Ruilin Cui, Tianliang Zhang, Feng He, Bocong Zheng, Jiting Ouyang
In this paper, multiple wave modes and transitions of argon helicon plasma excited by a half right-helical antenna in a system without any reflection endplate are investigated experimentally and theoretically at increasing radio frequency (RF) powers and external magnetic fields. Experiments show that above a critical magnetic field strength and pressure (about 250 G and 0.3 Pa in this work), two to
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Hybrid simulation of instabilities in capacitively coupled RF CF4/Ar plasmas driven by a dual frequency source Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-22 Wan Dong, Yi-Fan Zhang, Julian Schulze, Yuan-Hong Song
Instabilities in capacitively coupled Ar/CF4 plasma discharges driven by dual frequency sources are investigated using a one-dimensional fluid/electron Monte Carlo hybrid model. Periodic oscillations of the electron density and temperature on the timescale of multiple low frequency (LF) periods are observed. As the electron density increases, an intense oscillation of the electron temperature within
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The biological effect of the physical energy of plasma Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-21 Y Li, F Zhao, D Liu, L Nie, X Lu
Since the publication of the initial paper on atmospheric pressure plasma sterilization by Dr Laroussi in 1996, researchers have contributed to the field with an extensive number of papers on plasma medicine. However, these studies have primarily concentrated on the biological impacts of the chemical reactive components generated by plasma, specifically focusing on the effects of reactive oxygen and
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Absolute calibration of the ratio of Xe/O two-photon absorption cross-sections for O-TALIF applications Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-21 Z Shu, N A Popov, S M Starikovskaia
The paper presents a calibration of the ratio of two-photon absorption cross-sections, σXe(2)/σO(2) , necessary for the absolute O-atom density measurements by two-photon absorption laser-induced fluorescence (TALIF) technique. To calibrate the ratio of the cross-sections, a special discharge with 100% dissociation of molecular oxygen, and so with a known ‘reference’ density of O-atom [O] ref=2⋅ [O2]
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Fine structure resolved excitation cross sections of singly ionized Ga for the modeling and diagnostics of Ga plasmas Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-21 Indhu Suresh, 0000-0001-6263-6563Priti2, R Srivastava, R K Gangwar
Calculation of electron impact excitation cross sections for singly charged Ga ions plays a crucial role in plasma modeling, facilitating the comprehension of plasma behavior, characteristics, and dynamics in diverse domains, such as astrophysics, fusion research, the semiconductor industry, etc. In the available literature, there is a notable scarcity of, or even a complete absence of, these cross
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Diagnostics and characterization of a novel multi gas layer RF atmospheric pressure plasma jet for polymer processing Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-21 Mehrnoush Narimisa, Yuliia Onyshchenko, Ivana Sremački, Anton Nikiforov, Rino Morent, Nathalie De Geyter
The quest to employ cold plasma sources at atmospheric pressure in polymer processing has emerged as a potent driving force behind their development. Atmospheric pressure operation of plasma jets provides potential cost reductions as well as easier handling and maintenance. In addition, their unique advantage of remote operation allows the substrate to be placed outside the source boundaries. This
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Dynamic response of nanosecond repetitively pulsed discharges to combustion dynamics: regime transitions driven by flame oscillations Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-19 Colin A Pavan, Santosh J Shanbhogue, Drew E Weibel, Felipe Gomez del Campo, Ahmed F Ghoniem, Carmen Guerra-Garcia
When using nanosecond repetitively pulsed discharges to actuate on dynamic combustion instabilities, the environment the discharge is created in is unsteady and changing on the timescale of the combustion processes. As a result, individual discharge pulses are triggered in a background gas that evolves at the timescale of combustion dynamics, and pulse-to-pulse variations may be observed during the
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Effect of the cathode surface temperature on the cathode fall layer parameters: experiment and simulation Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-16 Leanid Simonchik, Mikalai Tomkavich, Gubad Islamov, Ender Eylenceoglu, Ismail Rafatov
Combined experimental and numerical studies reveal a significant effect of the cathode temperature on the basic parameters (such as the electric field profile, thickness of the cathode fall layer, current density, and gas temperature) of the cathode fall of the self-sustained normal direct current atmospheric pressure glow discharge (APGD) in helium. Numerical models are spatially one- and two-dimensional
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Zeeman effect of isotopes of Kr and Xe investigated at the linear plasma device PSI-2 Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-16 M Sackers, O Marchuk, D Dipti, Yu Ralchenko, S Ertmer, S Brezinsek, A Kreter
Laser absorption spectroscopy provides high-resolution spectra of atomic transitions that reveal many often inaccessible features. The line shapes of krypton and xenon measured in magnetized plasmas are strongly affected by the contribution of the odd-numbered isotopes 83Kr, 129Xe and 131Xe due to their hyperfine structure, creating more challenging spectra in comparison to even-numbered ones. The
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A tutorial overview of the angular scattering models of electron–neutral, ion–neutral, neutral–neutral, and Coulomb collisions in Monte Carlo collision modeling on low-temperature plasma Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-16 Wei Yang
Over the past decade, extensive modeling practices on low-temperature plasmas have revealed that input data such as microscopic scattering cross-sections are crucial to output macroscopic phenomena. In Monte Carlo collision (MCC) modeling of natural and laboratory plasma, the angular scattering model is a non-trivial topic. Conforming to the pedagogical purpose of this overview, the classical and quantum
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Absolute atomic nitrogen density spatial mapping in three MHCD configurations Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-14 Alice Remigy, Belkacem Menacer, Konstantinos Kourtzanidis, Odhisea Gazeli, Kristaq Gazeli, Guillaume Lombardi, Claudia Lazzaroni
In this work, nanosecond two-photon absorption laser induced fluorescence (TALIF) is used to perform spatial mappings of the absolute density of nitrogen atoms generated in a micro-hollow cathode discharge (MHCD). The MHCD is operated in the normal regime, with a DC discharge current of 1.6 mA and the plasma is ignited in a 20% Ar/ 80% N2 gas mixture. A 1-inch diameter aluminum substrate, acting as
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An experimental and computational study on the ignition process of a pulse modulated dual-RF capacitively coupled plasma operated at various low-frequency voltage amplitudes Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-13 De-Hua Shi, Xiao-Kun Wang, Yong-Xin Liu, Zoltán Donkó, Julian Schulze, You-Nian Wang
The ignition process of a pulse modulated capacitively coupled argon discharge driven simultaneously by two radio frequency voltages [12.5 MHz (high frequency) and 2.5 MHz (low frequency, LF)] is investigated by multifold experimental diagnostics and particle in cell / Monte Carlo collision simulations. In particular, (i) the effects of the LF voltage amplitude measured at the end of the pulse-on period
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Investigation of small-fraction molecular impurities in high-pressure helium plasmas using optical plasma diagnostic methods Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-09 Keiichiro Urabe, Minami Toyoda, Yoshinori Matsuoka, Koji Eriguchi
In high-pressure plasmas using gases diluted via a rare gas, small-fraction impurities in the discharge space significantly impact the basic plasma parameters and excited-species generation processes. This study investigated the behaviors of molecular impurities in a dielectric barrier discharge (DBD) generated in a flow of high-purity He gas using optical plasma diagnostic methods. The optical emission
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Spatio-temporal electric field distributions in an atmospheric plasma jet impinging on a microchannel array surface Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-09 S Raskar, I V Adamovich, K Konina, M J Kushner
The electric field distribution in the ionization waves (IWs) propagating over a microchannel array dielectric surface, with the channels either empty or filled with distilled water, is measured by ps electric field induced second harmonic generation. The surface IW is initiated by the atmospheric pressure N2–Ar plasma jet impinging on the surface vertically and powered by ns pulse discharge bursts
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Disorder-induced heating as a mechanism for fast neutral gas heating in atmospheric pressure plasmas Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-08 M D Acciarri, C Moore, S D Baalrud
Recent findings suggest that ions are strongly correlated in atmospheric pressure plasmas if the ionization fraction is sufficiently high ( ≳10−5 ). A consequence is that ionization causes disorder-induced heating (DIH), which triggers a significant rise in ion temperature on a picosecond timescale. This is followed by a rise in the neutral gas temperature on a longer timescale of up to nanoseconds
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Theoretical mechanism behind the higher efficiency of O than OH radicals in polypropylene surface modification: a molecular dynamics study Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-06 Hao Du, Masahiro Sato, Atsushi Komuro, Ryo Ono
O and OH radicals are the most important reactive oxygen species in the plasma treatment of polymer surfaces. In our previous studies, we found that the modification efficiency of polypropylene (PP) surface by O radicals was approximately four times higher than that by OH radicals. This observation contrasts with the well-established fact that the chemical reactivity of O radicals with saturated hydrocarbons
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Non-Maxwellian electron effects on the macroscopic response of a Hall thruster discharge from an axial–radial kinetic model Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-06 Alberto Marín-Cebrián, Enrique Bello-Benítez, Adrián Domínguez-Vázquez, Eduardo Ahedo
A 2D axial–radial particle-in-cell (PIC) model of a Hall thruster discharge has been developed to analyze (mainly) the fluid equations satisfied by the azimuthally-averaged slow dynamics of electrons. Their weak collisionality together with a strong interaction with the thruster walls lead to a non-Maxwellian velocity distribution function (VDF). Consequently, the resulting macroscopic response differs
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3D simulations of positive streamers in air in a strong external magnetic field Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-06 Zhen Wang, Anbang Sun, Saša Dujko, Ute Ebert, Jannis Teunissen
We study how external magnetic fields from 0 to 40 T influence positive streamers in atmospheric pressure air, using 3D PIC-MCC (particle-in-cell, Monte Carlo collision) simulations. When a magnetic field B is applied perpendicular to the background electric field E , the streamers deflect towards the +B and −B directions which results in a branching into two main channels. With a stronger magnetic
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A pointwise separation algorithm to separate plasma density and thickness in two-beam interferometry Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-05 Malong Fu, Haitao Wang, Zhongyu Hou
The conventional two-beam interferometry adopts only one expression about plasma density and thickness because only fringe shift is recognized from the recorded fringes. Therefore, the prior hypotheses that the plasma is thickness-uniform or circular symmetry have to be introduced to separate them, which limits the applied range and accuracy of the conventional method. This paper found that the laser
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Numerical investigation on the discharge formation in micrometer pores in structured catalyst irradiated by a helium atmospheric pressure plasma jet Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-05 Ning Wenjun, Shang Hao, Shen Xueming, Shen Saikang, Huang Xiaolong, Zhao Lihua, Jia Shenli
Non-thermal plasma catalysis is a promising way to achieve high efficiency in applications such as energy conversion and chemical engineering. Although synergistic effects between plasmas and catalysts have been preliminarily considered as an underlying mechanism of this type of catalysis, the formation of discharges in small-size catalyst pores, which is possibly a crucial factor in plasma-activated
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Frequency-dependent electron power absorption mode transitions in capacitively coupled argon-oxygen plasmas Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-05 A Derzsi, M Vass, R Masheyeva, B Horváth, Z Donkó, P Hartmann
Phase Resolved Optical Emission Spectroscopy (PROES) measurements combined with 1d3v Particle-in-Cell/Monte Carlo Collisions simulations are performed to investigate the excitation dynamics in low-pressure capacitively coupled plasmas (CCPs) in argon-oxygen mixtures. The system used for this study is a geometrically symmetric CCP reactor operated in a 70% Ar-30% O2 mixture at 120 Pa, applying a peak-to-peak
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Concentration measurements of atomic nitrogen in an atmospheric-pressure RF plasma jet using a picosecond TALIF Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-02 Waseem Khan, Pavel Dvořák, Nima Bolouki, Martina Mrkvičková
The absolute concentration and spatial distribution of ground-state atomic nitrogen (N) in an atmospheric pressure plasma jet were measured using the two-photon absorption laser-induced fluorescence. The jet was ignited by radio frequency voltage in argon (or argon with nitrogen admixture) flowing through a silica tube. The spatially resolved measurements of atomic nitrogen concentration were realized
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Detection of negative ions in streamer discharge in air by transient cavity ringdown spectroscopy Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-02 Kimika Fushimi, Naoki Shirai, Koichi Sasaki
Atmospheric-pressure discharges generated in air are expected to be electronegative, but experiments that examine negative ion densities are limited to date. In this work, we measured the temporal variation of the negative ion density in a streamer discharge generated in air. We adopted cavity ringdown spectroscopy, where negative ions were detected via weak optical absorption caused by laser photodetachment
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Low-pressure inductively coupled plasmas in hydrogen: impact of gas heating on the spatial distribution of atomic hydrogen and vibrationally excited states Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-02 Gregory J Smith, Paola Diomede, Andrew R Gibson, Scott J Doyle, Vasco Guerra, Mark J Kushner, Timo Gans, James P Dedrick
Non-equilibrium inductively coupled plasmas (ICPs) operating in hydrogen are of significant interest for applications including large-area materials processing. Increasing control of spatial gas heating, which drives the formation of neutral species density gradients and the rate of gas-temperature-dependent reactions, is critical. In this study, we use 2D fluid-kinetic simulations with the Hybrid
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Kinetic model of grating-like DBD fed with flowing humid air Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-02-02 Liyang Zhang, Zhigang Liu, Yuntao Guo, Jinbao Liu, Kai Wang, Haiyun Luo, Yangyang Fu
This work proposes a coupled kinetic model to capture the spatiotemporal evolution behaviors of reactive species generated by a grating-like dielectric barrier discharge (DBD) operated in flowing humid air. The coupled model incorporates a zero-dimensional (0D) discharge model for the discharge filament and a 0D kinetic model or two-dimensional (2D) fluid model for the afterglow region. The model is
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A new 2D fluid-MC hybrid approach for simulating nonequilibrium atmospheric pressure plasmas: density distribution of atomic oxygen in radio-frequency plasma jets in He/O2 mixtures Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-30 Máté Vass, David Schulenberg, Zoltán Donkó, Ihor Korolov, Peter Hartmann, Julian Schulze, Thomas Mussenbrock
A spatially two dimensional fluid-MC hybrid (fluid-kinetic) simulation method is developed and applied to the COST reference microplasma jet operated in helium with an oxygen admixture of 0.5%, excited by a single frequency voltage waveform with f = 13.56 MHz and ϕrms=275 V. The simulation approach is based on a fluid model augmented by a Monte Carlo module that generates electron impact rates for
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Streamer-induced kinetics of excited states in pure N2: II. Formation of N2(B 3Πg,v=0–21 ) through analysis of emission produced by the first positive system Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-30 Petr Bílek, Tiago Cunha Dias, Václav Prukner, Vasco Guerra, Milan Šimek
Vibrational distributions of electronically excited states of N2 obtained through dipole-allowed radiative transitions provide an important tool to study the kinetics of non-equilibrium plasmas under various discharge conditions. In this work, we report, for the first time, streamer-induced visible/near-infra-red emission spectra developing during the first hundred nanoseconds after the initiation
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Numerical model of restrikes in gliding arc discharges Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-25 Aymeric Bourlet, Fabien Tholin, Julien Labaune, François Pechereau, Axel Vincent-Randonnier, Christophe O Laux
Direct current (DC) electric arcs are of particular interest because they can produce large volumes of thermal plasmas with controlled energy deposition. When such discharges are applied in a gas flow, convection displaces the top of the arc downstream while the arc roots remain attached to the electrodes, thus increasing the length of the arc over time. However, this growth is limited by a restrike
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Ultralong-lasting plasma-activated water: production and control mechanisms Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-23 Congfu Ran, Xiongfeng Zhou, Zhiyong Wang, Kun Liu, Kostya (Ken) Ostrikov
Despite the rapidly growing interest stemming from the broad-spectrum, high inactivation capacity, and environmental friendliness of the plasma-activated water (PAW), practical applications are limited because of the PAW’s short lifetime. While low-temperature storage can extend the lifetime, but the freezing and thawing processes are energy- and labor-intense and are generally not suitable for large-scale
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Numerical optimization of dielectric properties to achieve process uniformity in capacitively coupled plasma reactors Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-22 Ho Jun Kim, Kyungjun Lee, Hwanyeol Park
This paper presents the results of our numerical analysis to optimize the dielectric properties to achieve process uniformity in the thin film deposition process using capacitively coupled plasma. The difference in the plasma density distribution was analyzed by changing the wafer material from silicon to quartz (or Teflon). Similarly, aluminum was compared with aluminum nitride as the electrode material
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A two-region model for azimuthal striations in an inductively coupled plasma Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-22 Meng-Zhi Gu, Zhi-Cheng Lei, Yi-Kang Pu
A two-region discharge model with a perturbation analysis was developed for the azimuthal striations observed in an inductively coupled plasma with an immersed cylindrical coil at pressures of 75–1500 mTorr. This model partitions the discharge area into two distinct regions: a bright region near the coil with intense excitation and ionization processes, and a darker region extending from the boundary
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Experimental investigation into efficiency loss in rotating magnetic field thrusters Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-17 T M Gill, C L Sercel, B A Jorns
An experimental investigation into the low thrust efficiency of a rotating magnetic field (RMF) thruster is presented. This technology is a low maturity but potentially enabling candidate for high-power in-space propulsion for use with alternative propellants. Direct thrust stand measurements of a 5 kW class RMF thruster were performed and show the thrust efficiency was 0.41 ± 0.04% with a specific
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Depopulation mechanisms of atomic hydrogen in the n = 3 level following two-photon excitation by a picosecond laser Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-12 Corinne Y Duluard, Laurent Invernizzi, Khaled Hassouni, Guillaume Lombardi, Kristaq Gazeli, Swaminathan Prasanna
One of the major constraints of measurements of atomic hydrogen densities using two-photon absorption laser induced fluorescence in most plasma and combustion environments is the determination of fluorescence decay times ( τfluo H ), especially when using nanosecond-lasers or slow acquisition systems. Therefore, it is necessary to identify the depopulation processes of the laser excited level in order
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Insights into spatial inhomogeneity in an oxygen plasma from cavity ringdown spectroscopy Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-12 Samuel D A Rogers, Amelia Bond, Robert Peverall, Gus Hancock, Grant A D Ritchie
Cavity ringdown spectroscopy has been used to investigate the translational and rotational temperatures of the v = 0 and 1 vibrational levels of O2(X) in an inductively coupled plasma at 100 mTorr (13.332 Pa) pressure. All rotational states probed display a clear increase in temperature as plasma power increases: at fixed power, the translational temperature appears largest for rotational states in
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Measurement of the main neutral species densities and temperatures in iodine plasmas using optical absorption techniques Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-11 Benjamin Esteves, Christophe Blondel, Pascal Chabert, Tanguy Michel, Cyril Drag
Iodine is a promising propellant for future plasma thrusters used in space propulsion. It is therefore important to understand the basic physics and chemistry of low-pressure iodine plasmas. In the present work, optical absorption methods are used to measure the densities of iodine molecules, I2, and iodine atoms, I, the translational temperature of the atoms and the dissociation fraction. The plasma
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Trumpet-shaped diffuse plasma jet in a semi-confined environment Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-08 Weisheng Cui, Li Chai, Ruobing Zhang
This paper reports a unique trumpet-shaped diffuse plasma jet (TDPJ) with a caliber exceeding 30 mm in a semi-confined environment, which is larger than the diameter of existing atmospheric pressure plasma jets (APPJs) in an open environment. The morphology of the TDPJ is attributed to the influence of the electric field on the development characteristics of ionization waves in the ambient environment
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Coupling the COST reference plasma jet to a microfluidic device: a computational study Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-04 Julien Bissonnette-Dulude, Pepijn Heirman, Sylvain Coulombe, Annemie Bogaerts, Thomas Gervais, Stephan Reuter
The use of microfluidic devices in the field of plasma-liquid interaction can unlock unique possibilities to investigate the effects of plasma-generated reactive species for environmental and biomedical applications. So far, very little simulation work has been performed on microfluidic devices in contact with a plasma source. We report on the modelling and computational simulation of physical and
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Atmospheric pressure plasmas interacting with wet and dry microchannels: reverse surface ionization waves Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-04 Kseniia Konina, Sai Raskar, Igor V Adamovich, Mark J Kushner
Atmospheric pressure plasma jets (APPJs) are increasingly being used to functionalize polymers and dielectric materials for biomedical and biotechnology applications. Once such application is microfluidic labs-on-a-chip consisting of dielectric slabs with microchannel grooves hundreds of microns in width and depth. The periodic channels, an example of a complex surface, present challenges in terms
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Spatio-temporal dynamics of electrons and helium metastables in uniform dielectric barrier discharges formed in He/N2 Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2024-01-04 Niklas Nawrath, Ihor Korolov, Nikita Bibinov, Peter Awakowicz, Andrew R Gibson
A uniform atmospheric pressure dielectric barrier discharge is operated in helium with an admixture (0.45%) of nitrogen. The discharge is ignited in the gas gap between a driven and a grounded electrode and propagates along the dielectric surface outside the gap. Plasma conditions are characterised with current and voltage measurements and by application of absolutely calibrated optical emission spectroscopy
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In situ measurement of the electron elastic reflection coefficient at a plasma-exposed silicon dioxide surface Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-28 Mark A Sobolewski
Plasma simulations require accurate input data that describe the interactions of electrons with plasma-exposed surfaces. One important, rarely studied interaction is elastic reflection. This article presents measurements of the elastic reflection coefficient made in situ, i.e. during plasma exposure, in an inductively coupled plasma (icp) reactor that has an azimuthally asymmetric, rf-biased substrate
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Plasma plume simulation of an atomic oxygen-fed ion thruster in very-low-earth-orbit Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-27 Geonwoong Moon, Wonho Choe, Eunji Jun
The plasma plume flow of an atomic oxygen-fed (AO-fed) ion thruster is numerically investigated as a simplification of the atmosphere-breathing electric propulsion (ABEP). A predictive analysis is conducted focusing on the ion backflow phenomenon and plume-background interaction in very-low-earth-orbit (VLEO). The computational framework employs two sequentially integrated numerical methods: a zero-dimensional
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Evolutions of streamer dynamics and discharge instabilities under repetitive pulses in humid air Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-22 Zheng Zhao, Qiuyu Gao, Xinlei Zheng, Haowei Zhang, Haotian Zheng, Anbang Sun, Jiangtao Li
The presence of water molecules in air introduces complexities to residual charge transports and energy relaxations that may provoke streamer discharge instabilities under repetitive pulses. Evolutions of pulse-periodic positive streamer dynamics were investigated in humid air. Pulse-sequence and temporally resolved diagnostics were implemented to capture discharge evolutions. The streamer development
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Simulation of filamentation dynamics of microwave discharge in nitrogen Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-20 A Saifutdinov, E Kustova
The present study deals with numerical simulations of microwave (MW) discharges in nitrogen based on extended fluid-dynamic model. The set of governing equations for non-equilibrium gas-discharge plasma includes conservation equations for species number densities, electron energy density, Poisson equation for the electric field coupled to the multi-temperature Navier–Stokes fluid-dynamic equations
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Particle simulations of ion-extraction process from a decaying plasma assisted by radio-frequency plasma heating Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-18 Jing-Yu Sun, Xing Chen, Kai Zhao, Cheng Yuan, Xiao-Yong Lu, Fei Gao, You-Nian Wang
In this study, two-dimensional kinetic particle simulations were employed to examine the potential of radio-frequency (rf) plasma heating in enhancing ion extraction efficiency in a decaying plasma with the configuration of parallel plates. The numerical results suggest that the application of rf power based on the direct current electrostatic method leads to a remarkable increase in the ion extraction
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First-principles simulation of optical emission spectra for low-pressure argon plasmas and its experimental validation Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-18 Fatima Jenina Arellano, Márton Gyulai, Zoltán Donkó, Peter Hartmann, Tsanko V Tsankov, Uwe Czarnetzki, Satoshi Hamaguchi
Various spectral line emissions are often used for the experimental characterization of low-temperature plasmas. For a better understanding of the relation between the plasma characteristics and optical emission spectra, first-principle numerical simulations for low-pressure radio-frequency driven capacitively-coupled plasmas (CCPs) of argon have been performed by coupling one-dimensional particle-in-cell/Monte
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Gas heating by inductively coupled low-pressure chlorine process plasmas Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-18 Dmitry Levko, Vivek Subramaniam, Laxminarayan L Raja
The mechanism of gas heating in low-pressure inductively coupled chlorine plasma is analyzed using a self-consistent two-dimensional axisymmetric fluid plasma model that is coupled with the compressible Navier–Stokes equations. For gas pressures of 10 and 20 mTorr and the discharge power in the range 0.1–1.3 kW, the main reactions contributing to gas heating were the ion–ion recombination reactions
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Insights into the copper HiPIMS discharge: deposition rate and ionised flux fraction Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-18 J Fischer, M Renner, J T Gudmundsson, M Rudolph, H Hajihoseini, N Brenning, D Lundin
The influence of pulse length, working gas pressure, and peak discharge current density on the deposition rate and ionised flux fraction in high power impulse magnetron sputtering discharges of copper is investigated experimentally using a charge-selective (electrically biasable) magnetically shielded quartz crystal microbalance (or ionmeter). The large explored parameter space covers both common process
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Availability and reactivity of N2(v) for NH3 synthesis by plasma catalysis Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-12 Brian N Bayer, Sai Raskar, Igor V Adamovich, Peter J Bruggeman, Aditya Bhan
Production of vibrationally excited N2 (N2(v)) in atmospheric pressure nonthermal plasma and loss of N2(v) by gas-phase reactions and reactions on catalytic surfaces are analyzed to examine the role of N2(v) in NH3 formation by plasma catalysis. Vibrational state-to-state kinetic models complemented with molecular beam mass spectrometry (MBMS) measurements demonstrate that N2(v> 0) is produced with
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Characterization of a radiofrequency linear plasma device in uniform and convergent magnetic fields Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-08 Kazunori Takahashi, Yume Teranishi
A linear radiofrequency plasma device is constructed, where a source operating at a frequency of 13.56 MHz and a maximum power of several kW is attached to a cylindrical vacuum chamber about 1 m in length. Seven solenoids are located around the source and the chamber, providing various magnetic field configurations by changing the solenoid currents. The plasma density of the radiofrequency linear plasma
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Particle-in-cell simulations of high frequency capacitively coupled plasmas including spatially localised inductive-like heating Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-07 M Osca Engelbrecht, C P Ridgers, J Dedrick, R Boswell
High frequency (HF) capacitively coupled plasmas (CCPs) are ubiquitous, having several industrial applications, especially in the semiconductor industry. Inductive heating effects within these plasmas play an important role and therefore understanding them is key to improve industrial applications. For this purpose kinetic research, using particle-in-cell (PIC) codes, offers significant opportunity
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Collision integrals of electronically excited atoms in air plasmas. I. N–N and O–O interactions Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-06 Wensheng Zhao, Qizhen Hong, Chao Yang, Quanhua Sun, Yuan Hu
The current work presents the collision integral data for N(4 S)–N(4 S, 2 D, 2 P) and O(3 P, 1 D, 1 S)–O(3 P, 1 D, 1 S) interactions in the temperature range of 500–50 000 K. The collision integrals are calculated based on high-quality potential energy curves (PECs) obtained from fitting the high-level ab initio calculation data in a wide energy range to the neural network (NN) functions. In the construction
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Plasma catalysis: separating plasma and surface contributions for an Ar/N2/O2 atmospheric discharge interacting with a Pt catalyst Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-12-06 Michael Hinshelwood, Gottlieb S Oehrlein
Atmospheric pressure non-equilibrium plasmas can form nitrogen oxide (NO x ) compounds directly from nitrogen and oxygen without a catalyst, and at lower catalyst temperatures than would be possible without plasma. In this work, the oxidation of plasma-produced NO from an Ar/N2/O2 non-equilibrium atmospheric-pressure plasma-jet (APPJ) over a platinum-on-alumina powder catalyst was investigated with
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Theoretical cross sections for electron collisions relevant for ammonia discharges part 1: NH3, NH2, and NH Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-11-30 Ramses Snoeckx, Jonathan Tennyson, Min Suk Cha
Besides being the worlds’ most important fertilizer precursor, ammonia could play an important role as hydrogen carrier in a decarbonized future. The efficient production and decomposition (or cracking) of ammonia are essential to this end. An electricity-driven technology of interest for both these processes are non-thermal plasmas. Plasma processes have the advantage of activating—even inert—molecules
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Emissive cathode immersed in a plasma: plasma–cathode interactions, operation and stability Plasma Sources Sci. Technol. (IF 3.8) Pub Date : 2023-11-28 F Pagaud, V Dolique, N Claire, N Plihon
Thermionic emission from a polycrystalline tungsten emissive cathode immersed in a magnetized plasma column is investigated experimentally and numerically. Electrical and optical measurements of the cathode temperature show a highly inhomogeneous cathode temperature profile due to plasma–cathode interactions. The spatially and temporally resolved cathode temperature profile provides an in-depth understanding