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	Author	Bogaerts, A.
	Title	Comprehensive modelling network for dc glow discharges in argon			Type	A1 Journal article
	Year	1999	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	8	Issue		Pages	210-229
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000080660600004	Publication Date	2002-08-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	27	Open Access
	Notes				Approved	Most recent IF: 3.302; 1999 IF: 2.038
	Call Number	UA @ lucian @ c:irua:24129			Serial	451
Permanent link to this record



	Author	Yan, M.; Bogaerts, A.; Goedheer, W.J.; Gijbels, R.
	Title	Electron energy distribution function in capacitively coupled RF discharges: differences between electropositive Ar and electronegative SiH₄ discharges			Type	A1 Journal article
	Year	2000	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	9	Issue		Pages	583-591
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000165341000015	Publication Date	2002-08-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	21	Open Access
	Notes				Approved	Most recent IF: 3.302; 2000 IF: 1.963
	Call Number	UA @ lucian @ c:irua:34071			Serial	929
Permanent link to this record



	Author	Bogaerts, A.; Gijbels, R.
	Title	The ion- and atom-induced secondary electron emission yield: numerical study for the effect of clean and dirty cathode surfaces			Type	A1 Journal article
	Year	2002	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	11	Issue		Pages	27-36
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000174336300003	Publication Date	2002-08-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	51	Open Access
	Notes				Approved	Most recent IF: 3.302; 2002 IF: 1.816
	Call Number	UA @ lucian @ c:irua:40184			Serial	1739
Permanent link to this record



	Author	Bogaerts, A.; Okhrimovskyy, A.; Baguer, N.; Gijbels, R.
	Title	Hollow cathode discharges with gas flow: numerical modelling for the effect on the sputtered atoms and the deposition flux			Type	A1 Journal article
	Year	2005	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	14	Issue		Pages	191-200
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000227652500021	Publication Date	2005-02-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	9	Open Access
	Notes				Approved	Most recent IF: 3.302; 2005 IF: 1.798
	Call Number	UA @ lucian @ c:irua:50478			Serial	1480
Permanent link to this record



	Author	Georgieva, V.; Bogaerts, A.
	Title	Plasma characteristics of an Ar/CF₄/N₂ discharge in an asymmetric dual frequency reactor: numerical investigation by a PIC/MC model			Type	A1 Journal article
	Year	2006	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	15	Issue		Pages	368-377
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000240655500010	Publication Date	2006-04-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	35	Open Access
	Notes				Approved	Most recent IF: 3.302; 2006 IF: 2.346
	Call Number	UA @ lucian @ c:irua:57550			Serial	2630
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	Author	Paulussen, S.; Verheyde, B.; Tu, X.; De Bie, C.; Martens, T.; Petrovic, D.; Bogaerts, A.; Sels, B.
	Title	Conversion of carbon dioxide to value-added chemicals in atmospheric pressure dielectric barrier discharges			Type	A1 Journal article
	Year	2010	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	19	Issue	3	Pages	034015,1-034015,6
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The aim of this work consists of the evaluation of atmospheric pressure dielectric barrier discharges for the conversion of greenhouse gases into useful compounds. Therefore, pure CO2 feed flows are administered to the discharge zone at varying discharge frequency, power input, gas temperature and feed flow rates, aiming at the formation of CO and O2. The discharge obtained in CO2 is characterized as a filamentary mode with a microdischarge zone in each half cycle of the applied voltage. It is shown that the most important parameter affecting the CO2-conversion levels is the gas flow rate. At low flow rates, both the conversion and the CO-yield are significantly higher. In addition, also an increase in the gas temperature and the power input give rise to higher conversion levels, although the effect on the CO-yield is limited. The optimum discharge frequency depends on the power input level and it cannot be unambiguously stated that higher frequencies give rise to increased conversion levels. A maximum CO2 conversion of 30% is achieved at a flow rate of 0.05 L min−1, a power density of 14.75 W cm−3 and a frequency of 60 kHz. The most energy efficient conversions are achieved at a flow rate of 0.2 L min−1, a power density of 11 W cm−3 and a discharge frequency of 30 kHz.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000277982800016	Publication Date	2010-05-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	116	Open Access
	Notes				Approved	Most recent IF: 3.302; 2010 IF: 2.218
	Call Number	UA @ lucian @ c:irua:82408			Serial	512
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	Author	Tinck, S.; Bogaerts, A.
	Title	Computer simulations of an oxygen inductively coupled plasma used for plasma-assisted atomic layer deposition			Type	A1 Journal article
	Year	2011	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	20	Issue	1	Pages	015008-015008,10
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this paper, an O2 inductively coupled plasma used for plasma enhanced atomic layer deposition of Al2O3 thin films is investigated by means of modeling. This work intends to provide more information about basic plasma properties such as species densities and species fluxes to the substrate as a function of power and pressure, which might be hard to measure experimentally. For this purpose, a hybrid model developed by Kushner et al is applied to calculate the plasma characteristics in the reactor volume for different chamber pressures ranging from 1 to 10 mTorr and different coil powers ranging from 50 to 500 W. Density profiles of the various oxygen containing plasma species are reported as well as fluxes to the substrate under various operating conditions. Furthermore, different orientations of the substrate, which can be placed vertically or horizontally in the reactor, are taken into account. In addition, special attention is paid to the recombination process of atomic oxygen on the different reactor walls under the stated operating conditions. From this work it can be concluded that the plasma properties change significantly in different locations of the reactor. The plasma density near the cylindrical coil is high, while it is almost negligible in the neighborhood of the substrate. Ion and excited species fluxes to the substrate are found to be very low and negligible. Finally, the orientation of the substrate has a minor effect on the flux of O2, while it has a significant effect on the flux of O. In the horizontal configuration, the flux of atomic oxygen can be up to one order of magnitude lower than in the vertical configuration.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000286592200009	Publication Date	2011-01-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	11	Open Access
	Notes				Approved	Most recent IF: 3.302; 2011 IF: 2.521
	Call Number	UA @ lucian @ c:irua:85285			Serial	467
Permanent link to this record



	Author	De Bie, C.; Martens, T.; van Dijk, J.; Paulussen, S.; Verheyde, B.; Corthals, S.; Bogaerts, A.
	Title	Dielectric barrier discharges used for the conversion of greenhouse gases: modeling the plasma chemistry by fluid simulations			Type	A1 Journal article
	Year	2011	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	20	Issue	2	Pages	024008,1-024008,11
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The conversion of methane to value-added chemicals and fuels is considered to be one of the challenges of the 21st century. In this paper we study, by means of fluid modeling, the conversion of methane to higher hydrocarbons or oxygenates by partial oxidation with CO2 or O2 in a dielectric barrier discharge. Sixty-nine different plasma species (electrons, ions, molecules, radicals) are included in the model, as well as a comprehensive set of chemical reactions. The calculation results presented in this paper include the conversion of the reactants and the yields of the reaction products as a function of residence time in the reactor, for different gas mixing ratios. Syngas (i.e. H2 + CO) and higher hydrocarbons (C2Hx) are typically found to be important reaction products.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000290719900009	Publication Date	2011-04-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	38	Open Access
	Notes				Approved	Most recent IF: 3.302; 2011 IF: 2.521
	Call Number	UA @ lucian @ c:irua:87868			Serial	689
Permanent link to this record



	Author	Bultinck, E.; Bogaerts, A.
	Title	Characterization of an Ar/O₂ magnetron plasma by a multi-species Monte Carlo model			Type	A1 Journal article
	Year	2011	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	20	Issue	4	Pages	045013-045013,12
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A combined Monte Carlo (MC)/analytical surface model is developed to study the plasma processes occurring during the reactive sputter deposition of TiOx thin films. This model describes the important plasma species with a MC approach (i.e. electrons, Ar+ ions, {\rm O}_2
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000295829800015	Publication Date	2011-06-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	7	Open Access
	Notes				Approved	Most recent IF: 3.302; 2011 IF: 2.521
	Call Number	UA @ lucian @ c:irua:89732			Serial	316
Permanent link to this record



	Author	Tinck, S.; Boullart, W.; Bogaerts, A.
	Title	Modeling Cl₂/O₂/Ar inductively coupled plasmas used for silicon etching : effects of SiO₂ chamber wall coating			Type	A1 Journal article
	Year	2011	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	20	Issue	4	Pages	045012-045012,19
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this paper, simulations are performed to gain a better insight into the properties of a Cl2/Ar plasma, with and without O2, during plasma etching of Si. Both plasma and surface properties are calculated in a self-consistent manner. Special attention is paid to the behavior of etch products coming from the wafer or the walls, and how the chamber walls can affect the plasma and the resulting etch process. Two modeling cases are considered. In the first case, the reactor walls are defined as clean (Al2O3), whereas in the second case a SiO2 coating is introduced on the reactor walls before the etching process, so that oxygen will be sputtered from the walls and introduced into the plasma. For this reason, a detailed reaction set is presented for a Cl2/O2/Ar plasma containing etched species, as well as an extensive reaction set for surface processes, including physical and chemical sputtering, chemical etching and deposition processes. Density and flux profiles of various species are presented for a better understanding of the bulk plasma during the etching process. Detailed information is also given on the composition of the surfaces at various locations of the reactor, on the etch products in the plasma and on the surface loss probabilities of the plasma species at the walls, with different compositions. It is found that in the clean chamber, walls are mostly chlorinated (Al2Cl3), with a thin layer of etch products residing on the wall. In the coated chamber, an oxy-chloride layer is grown on the walls for a few nanometers during the etching process. The Cl atom wall loss probability is found to decrease significantly in the coated chamber, hence increasing the etch rate. SiCl2, SiCl4 and SiCl3 are found to be the main etch products in the plasma, with the fraction of SiCl2 being always slightly higher. The simulation results compare well with experimental data available from the literature.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000295829800014	Publication Date	2011-06-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	22	Open Access
	Notes				Approved	Most recent IF: 3.302; 2011 IF: 2.521
	Call Number	UA @ lucian @ c:irua:91045			Serial	2141
Permanent link to this record



	Author	Zhao, S.-X.; Gao, F.; Wang, Y.-N.; Bogaerts, A.
	Title	The effect of F₂ attachment by low-energy electrons on the electron behaviour in an Ar/CF₄ inductively coupled plasma			Type	A1 Journal article
	Year	2012	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	21	Issue	2	Pages	025008-025008,13
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The electron behaviour in an Ar/CF4 inductively coupled plasma is investigated by a Langmuir probe and a hybrid model. The simulated and measured results include electron density, temperature and electron energy distribution function for different values of Ar/CF4 ratio, coil power and gas pressure. The hybrid plasma equipment model simulations show qualitative agreement with experiment. The effect of F2 electron attachment on the electron behaviour is explored by comparing two sets of data based on different F atom boundary conditions. It is demonstrated that electron attachment at F2 molecules is responsible for the depletion of low-energy electrons, causing a density decrease as well as a temperature increase when CF4 is added to an Ar plasma.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000302779400022	Publication Date	2012-03-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	23	Open Access
	Notes				Approved	Most recent IF: 3.302; 2012 IF: 2.515
	Call Number	UA @ lucian @ c:irua:96549			Serial	841
Permanent link to this record



	Author	Zhao, S.-X.; Gao, F.; Wang, Y.-N.; Bogaerts, A.
	Title	Gas ratio effects on the Si etch rate and profile uniformity in an inductively coupled Ar/CF₄ plasma			Type	A1 Journal article
	Year	2013	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	22	Issue	1	Pages	015017-15018
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this work, a hybrid model is used to investigate the effect of different gas ratios on the Si etching and polymer film deposition characteristics in an Ar/CF4 inductively coupled plasma. The influence of the surface processes on the bulk plasma properties is studied, and also the spatial characteristics of important gas phase and etched species. The densities of F and CF2 decrease when the surface module is included in the simulations, due to the species consumption caused by etching and polymer deposition. The influence of the surface processes on the bulk plasma depends on the Ar/CF4 gas ratio. The deposited polymer becomes thicker at high CF4 content because of more abundant CFx radicals. As a result of the competition between the polymer thickness and the F flux, the etch rate first increases and then decreases upon increasing the CF4 content. The electron properties, more specifically the electron density profile, affect the Si etch characteristics substantially by determining the radical density and flux profiles. In fact, the radial profile of the etch rate is more uniform at low CF4 content since the electron density has a smooth distribution. At high CF4 content, the etch rate is less uniform with a minimum halfway along the wafer radius, because the electron density distribution is more localized. Therefore, our calculations predict that it is better to work at relatively high Ar/CF4 gas ratios, in order to obtain high etch rate and good profile uniformity for etch applications. This, in fact, corresponds to the typical experimental etch conditions in Ar/CF4 gas mixtures as found in the literature, where Ar is typically present at a much higher concentration than CF4.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000314966300022	Publication Date	2012-12-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	11	Open Access
	Notes				Approved	Most recent IF: 3.302; 2013 IF: 3.056
	Call Number	UA @ lucian @ c:irua:102583			Serial	1320
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	Author	Liu, Y.-X.; Zhang, Q.-Z.; Liu, L.; Song, Y.-H.; Bogaerts, A.; Wang, Y.-N.
	Title	Electron bounce resonance heating in dual-frequency capacitively coupled oxygen discharges			Type	A1 Journal article
	Year	2013	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	22	Issue	2	Pages	025012-11
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The electron bounce resonance heating (BRH) in dual-frequency capacitively coupled plasmas operated in oxygen is studied by different experimental methods and a particle-in-cell/Monte Carlo collision (PIC/MCC) simulation, and compared with the electropositive argon discharge. In comparison with argon, the experimental results show that in an oxygen discharge the resonance peaks in positive-ion density and light intensity tend to occur at larger electrode gaps. Moreover, at electrode gaps L > 2.5 cm, the positive-ion (and electron) density and the light emission drop monotonically in the oxygen discharge upon increasing L, whereas they rise (after an initial drop) in the argon case. At resonance gap the electronegativity reaches its maximum due to the BRH. All these experimental observations are explained by PIC/MCC simulations, which show that in the oxygen discharge the bulk electric field becomes quite strong and is out of phase with the sheath field. Therefore, it retards the resonance electrons when traversing the bulk, resulting in a suppressed BRH. Both experiment and simulation results show that this effect becomes more pronounced at lower high-frequency power, when the discharge mode changes from electropositive to electronegative. In a pure oxygen discharge, the BRH is suppressed with increasing pressure and almost diminishes at 12 Pa. Finally, the driving frequency significantly affects the BRH, because it determines the phase relation between bulk electric field and sheath electric field.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000317275400014	Publication Date	2013-03-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	20	Open Access
	Notes				Approved	Most recent IF: 3.302; 2013 IF: 3.056
	Call Number	UA @ lucian @ c:irua:106534			Serial	911
Permanent link to this record



	Author	Van Laer, K.; Tinck, S.; Samara, V.; de Marneffe, J.F.; Bogaerts, A.
	Title	Etching of low-k materials for microelectronics applications by means of a N₂/H₂ plasma : modeling and experimental investigation			Type	A1 Journal article
	Year	2013	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	22	Issue	2	Pages	025011-25019
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this paper, we investigate the etch process of so-called low-k organic material by means of a N2/H2 capacitively coupled plasma, as applied in the micro-electronics industry for the manufacturing of computer chips. In recent years, such an organic material has emerged as a possible alternative for replacing bulk SiO2 as a dielectric material in the back-end-of-line, because of the smaller parasitic capacity between adjacent conducting lines, and thus a faster propagation of the electrical signals throughout the chip. Numerical simulations with a hybrid plasma model, using an extensive plasma and surface chemistry set, as well as experiments are performed, focusing on the plasma properties as well as the actual etching process, to obtain a better insight into the underlying mechanisms. Furthermore, the effects of gas pressure, applied power and gas composition are investigated to try to optimize the etch process. In general, the plasma density reaches a maximum near the wafer edge due to the so-called 'edge effect'. As a result, the etch rate is not uniform but will also reach its maximum near the wafer edge. The pressure seems not to have a big effect. A higher power increases the etch rate, but the uniformity becomes (slightly) worse. The gas mixing ratio has no significant effect on the etch process, except when a pure H2 or N2 plasma is used, illustrating the synergistic effects of a N2/H2 plasma. In fact, our calculations reveal that the N2/H2 plasma entails an ion-enhanced etch process. The simulation results are in reasonable agreement with the experimental values. The microscopic etch profile shows the desired anisotropic shape under all conditions under study.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000317275400013	Publication Date	2013-03-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	13	Open Access
	Notes				Approved	Most recent IF: 3.302; 2013 IF: 3.056
	Call Number	UA @ lucian @ c:irua:106654			Serial	1084
Permanent link to this record



	Author	Zhang, Q.-Z.; Liu, Y.-X.; Jiang, W.; Bogaerts, A.; Wang, Y.-N.
	Title	Heating mechanism in direct current superposed single-frequency and dual-frequency capacitively coupled plasmas			Type	A1 Journal article
	Year	2013	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	22	Issue	2	Pages	025014-25018
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this work particle-in-cell/Monte Carlo collision simulations are performed to study the heating mechanism and plasma characteristics in direct current (dc) superposed radio-frequency (RF) capacitively coupled plasmas, operated both in single-frequency (SF) and dual-frequency (DF) regimes. An RF (60/2 MHz) source is applied on the bottom electrode to sustain the discharge, and a dc source is fixed on the top electrode. The heating mechanism appears to be very different in dc superposed SF and DF discharges. When only a single source of 60 MHz is applied, the plasma bulk region is reduced by the dc source, thus the ionization rate and hence the electron density decrease with rising dc voltage. However, when a DF source of 60 and 2 MHz is applied, the electron density can increase upon addition of a dc voltage, depending on the gap length and applied dc voltage. This is explained from the spatiotemporal ionization rates in the DF discharge. In fact, a completely different behavior is observed for the ionization rate in the two half-periods of the LF source. In the first LF half-period, the situation resembles the dc superposed SF discharge, and the reduced plasma bulk region due to the negative dc bias results in a very small effective discharge area and a low ionization rate. On the other hand, in the second half-period, the negative dc bias is to some extent counteracted by the LF voltage, and the sheath close to the dc electrode becomes particularly thin. Consequently, the amplitude of the high-frequency sheath oscillations at the top electrode is largely enhanced, while the LF sheath at the bottom electrode is in its expanding phase and can thus well confine the high-energy electrons. Therefore, the ionization rate increases considerably in this second LF half-period. Furthermore, in addition to the comparison between SF and DF discharges and the effect of gap length and dc voltage, the effect of secondary electrons is examined.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000317275400016	Publication Date	2013-03-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	9	Open Access
	Notes				Approved	Most recent IF: 3.302; 2013 IF: 3.056
	Call Number	UA @ lucian @ c:irua:106877			Serial	1413
Permanent link to this record



	Author	Van Gaens, W.; Bogaerts, A.
	Title	Reaction pathways of biomedically active species in an Ar plasma jet			Type	A1 Journal article
	Year	2014	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	23	Issue	3	Pages	035015-35027
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this paper we analyse the gas phase production and loss pathways for several biomedically active species, i.e. N2(A), O, O3, O2(a), N, H, HO2, OH, NO, NO2, N2O5, H2O2, HNO2 and HNO3, in an argon plasma jet flowing into an open humid air atmosphere. For this purpose, we employ a zero-dimensional reaction kinetics model to mimic the typical experimental conditions by fitting several parameters to experimentally measured values. These include ambient air diffusion, the gas temperature profile and power deposition along the jet effluent. We focus in detail on how the pathways of the biomedically active species change as a function of the position in the effluent, i.e. inside the discharge device, active plasma jet effluent and afterglow region far from the nozzle. Moreover, we demonstrate how the reaction kinetics and species production are affected by different ambient air humidities, total deposited power into the plasma and gas temperature along the jet. It is shown that the dominant pathways can drastically change as a function of the distance from the nozzle exit or experimental conditions.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000337891900017	Publication Date	2014-05-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	34	Open Access
	Notes				Approved	Most recent IF: 3.302; 2014 IF: 3.591
	Call Number	UA @ lucian @ c:irua:117075			Serial	2820
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	Author	Kozák, T.; Bogaerts, A.
	Title	Splitting of CO₂ by vibrational excitation in non-equilibrium plasmas : a reaction kinetics model			Type	A1 Journal article
	Year	2014	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	23	Issue	4	Pages	045004
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	We present a zero-dimensional kinetic model of CO2 splitting in non-equilibrium plasmas. The model includes a description of the CO2 vibrational kinetics (25 vibrational levels up to the dissociation limit of the molecule), taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is applied to study the reaction kinetics of CO2 splitting in an atmospheric-pressure dielectric barrier discharge (DBD) and in a moderate-pressure microwave discharge. The model results are in qualitative agreement with published experimental works. We show that the CO2 conversion and its energy efficiency are very different in these two types of discharges, which reflects the important dissociation mechanisms involved. In the microwave discharge, excitation of the vibrational levels promotes efficient dissociation when the specific energy input is higher than a critical value (2.0 eV/molecule under the conditions examined). The calculated energy efficiency of the process has a maximum of 23%. In the DBD, vibrationally excited levels do not contribute significantly to the dissociation of CO2 and the calculated energy efficiency of the process is much lower (5%).
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000345761500014	Publication Date	2014-06-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	170	Open Access
	Notes				Approved	Most recent IF: 3.302; 2014 IF: 3.591
	Call Number	UA @ lucian @ c:irua:117398			Serial	3108
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	Author	Kolev, S.; Bogaerts, A.
	Title	A 2D model for a gliding arc discharge			Type	A1 Journal article
	Year	2015	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	24	Issue	24	Pages	015025
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this study we report on a 2D fluid model of a gliding arc discharge in argon. Despite the 3D nature of the discharge, 2D models are found to be capable of providing very useful information about the operation of the discharge. We employ two modelsan axisymmetric and a Cartesian one. We show that for the considered experiment and the conditions of a low current arc (around 30 mA) in argon, there is no significant heating of the cathode surface and the discharge is sustained by field electron emission from the cathode accompanied by the formation of a cathode spot. The obtained discharge power and voltage are relatively sensitive to the surface properties and particularly to the surface roughness, causing effectively an amplification of the normal electric field. The arc body and anode region are not influenced by this and depend mainly on the current value. The gliding of the arc is modelled by means of a 2D Cartesian model. The arcelectrode contact points are analysed and the gliding mechanism along the electrode surface is discussed. Following experimental observations, the cathode spot is simulated as jumping from one point to another. A complete arc cycle is modelled from initial ignition to arc decay. The results show that there is no interaction between the successive gliding arcs.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000348298200026	Publication Date	2014-12-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	34	Open Access
	Notes				Approved	Most recent IF: 3.302; 2015 IF: 3.591
	Call Number	c:irua:122538 c:irua:122538 c:irua:122538 c:irua:122538			Serial	3
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	Author	Kozák, T.; Bogaerts, A.
	Title	Evaluation of the energy efficiency of CO₂ conversion in microwave discharges using a reaction kinetics model			Type	A1 Journal article
	Year	2015	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	24	Issue	24	Pages	015024
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	We use a zero-dimensional reaction kinetics model to simulate CO2 conversion in microwave discharges where the excitation of the vibrational levels plays a significant role in the dissociation kinetics. The model includes a description of the CO2 vibrational kinetics, taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is used to simulate a general tubular microwave reactor, where a stream of CO2 flows through a plasma column generated by microwave radiation. We study the effects of the internal plasma parameters, namely the reduced electric field, electron density and the total specific energy input, on the CO2 conversion and its energy efficiency. We report the highest energy efficiency (up to 30%) for a specific energy input in the range 0.41.0 eV/molecule and a reduced electric field in the range 50100 Td and for high values of the electron density (an ionization degree greater than 10−5). The energy efficiency is mainly limited by the VT relaxation which contributes dominantly to the vibrational energy losses and also contributes significantly to the heating of the reacting gas. The model analysis provides useful insight into the potential and limitations of CO2 conversion in microwave discharges.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000348298200025	Publication Date	2014-12-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	100	Open Access
	Notes				Approved	Most recent IF: 3.302; 2015 IF: 3.591
	Call Number	c:irua:122243			Serial	1087
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	Author	Peerenboom, K.; Parente, A.; Kozák, T.; Bogaerts, A.; Degrez, G.
	Title	Dimension reduction of non-equilibrium plasma kinetic models using principal component analysis			Type	A1 Journal article
	Year	2015	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	24	Issue	24	Pages	025004
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The chemical complexity of non-equilibrium plasmas poses a challenge for plasma modeling because of the computational load. This paper presents a dimension reduction method for such chemically complex plasmas based on principal component analysis (PCA). PCA is used to identify a low-dimensional manifold in chemical state space that is described by a small number of parameters: the principal components. Reduction is obtained since continuity equations only need to be solved for these principal components and not for all the species. Application of the presented method to a CO2 plasma model including state-to-state vibrational kinetics of CO2 and CO demonstrates the potential of the PCA method for dimension reduction. A manifold described by only two principal components is able to predict the CO2 to CO conversion at varying ionization degrees very accurately.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000356816200008	Publication Date	2015-01-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	11	Open Access
	Notes				Approved	Most recent IF: 3.302; 2015 IF: 3.591
	Call Number	c:irua:123534			Serial	704
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	Author	Kolev, S.; Bogaerts, A.
	Title	Similarities and differences between gliding glow and gliding arc discharges			Type	A1 Journal article
	Year	2015	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	24	Issue	24	Pages	065023
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this work we have analyzed the properties of a gliding dc discharge in argon at atmospheric pressure. Despite the usual designation of these discharges as ‘gliding arc discharges’, it was found previously that they operate in two different regimes—glow and arc. Here we analyze the differences in both regimes by means of two dimensional fluid modeling. In order to address different aspects of the discharge operation, we use two models—Cartesian and axisymmetric in a cylindrical coordinate system. The obtained results show that the two types of discharges produce a similar plasma column for a similar discharge current. However, the different mechanisms of plasma channel attachment to the cathode could produce certain differences in the plasma parameters (i.e. arc elongation), and this can affect gas treatments applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000368117100028	Publication Date	2015-11-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	12	Open Access
	Notes	This work is financially supported by the Methusalem financing and by the IAP/7 (Inter-university Attraction Pole) program ‘Physical Chemistry of Plasma-Surface Interactions’ from the Belgian Federal Office for Science Policy (BELSPO). The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen			Approved	Most recent IF: 3.302; 2015 IF: 3.591
	Call Number	c:irua:129214			Serial	3952
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	Author	Van Laer, K.; Bogaerts, A.
	Title	Fluid modelling of a packed bed dielectric barrier discharge plasma reactor			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	015002
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A packed bed dielectric barrier discharge plasma reactor is computationally studied with a fluid model. Two different complementary axisymmetric 2D geometries are used to mimic the intrinsic 3D problem. It is found that a packing enhances the electric field strength and electron temperature at the contact points of the dielectric material due to polarization of the beads by the applied potential. As a result, these contact points prove to be of direct importance to initiate the plasma. At low applied potential, the discharge stays at the contact points, and shows the properties of a Townsend discharge. When a high enough potential is applied, the plasma will be able to travel through the gaps in between the beads from wall to wall, forming a kind of glow discharge. Therefore, the inclusion of a so-called ‘channel of voids’ is indispensable in any type of packed bed modelling.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000370974800009	Publication Date	2015-12-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	50	Open Access
	Notes	The authors gratefully thank St Kolev for the many interesting discussions and the useful advise in setting up the models. This research was carried out in the framework of the network on Physical Chemistry of Plasma-Surface Interactions— Interuniversity Attraction Poles, phase VII (http://psi-iap7.ulb. ac.be/), and supported by the Belgian Science Policy Office (BELSPO). K Van Laer is indebted to the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT Flanders) for financial support.			Approved	Most recent IF: 3.302
	Call Number	c:irua:129802			Serial	3982
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	Author	Belov, I.; Paulussen, S.; Bogaerts, A.
	Title	Appearance of a conductive carbonaceous coating in a CO₂dielectric barrier discharge and its influence on the electrical properties and the conversion efficiency			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	015023
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	This work examines the properties of a dielectric barrier discharge (DBD) reactor, built for CO2 decomposition, by means of electrical characterization, optical emission spectroscopy and gas chromatography. The discharge, formed in an electronegative gas (such as CO2, but also O2), exhibits clearly different electrical characteristics, depending on the surface conductivity of the reactor walls. An asymmetric current waveform is observed in the metaldielectric (MD) configuration, with sparse high-current pulses in the positive half-cycle (HC) and a more uniform regime in the negative HC. This indicates that the discharge is operating in two alternating regimes with rather different properties. At high CO2 conversion regimes, a conductive coating is deposited on the dielectric. This so-called coated MD configuration yields a symmetric current waveform, with current peaks in both the positive and negative HCs. In a double-dielectric (DD) configuration, the current waveform is also symmetric, but without current peaks in both the positive and negative HC. Finally, the DD configuration with conductive coating on the inner surface of the outer dielectric, i.e. so-called coated DD, yields again an asymmetric current waveform, with current peaks in the negative HC. These different electrical characteristics are related to the presence of the conductive coating on the dielectric wall of the reactor and can be explained by an increase of the local barrier capacitance available for charge transfer. The different discharge regimes affect the CO2 conversion, more specifically, the CO2 conversion is lowest in the clean DD configuration. It is somewhat higher in the coated DD configuration, and still higher in the MD configuration. The clean and coated MD configuration, however, gave similar CO2 conversion. These results indicate that the conductivity of the dielectric reactor walls can highly promote the development of the high-amplitude discharge current pulses and subsequently the CO2 conversion.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000370974800030	Publication Date	2016-01-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	25	Open Access
	Notes	The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7-PEOPLE-2013-ITN) under Grant Agreement № 606889 (RAPID—Reactive Atmospheric Plasma processIng—eDucation network).			Approved	Most recent IF: 3.302
	Call Number	c:irua:130790			Serial	4006
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	Author	Ozkan, A.; Dufour, T.; Silva, T.; Britun, N.; Snyders, R.; Bogaerts, A.; Reniers, F.
	Title	The influence of power and frequency on the filamentary behavior of a flowing DBD—application to the splitting of CO₂			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	025013
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this experimental study, a flowing dielectric barrier discharge operating at atmospheric pressure is used for the splitting of CO2 into O2 and CO. The influence of the applied frequency and plasma power on the microdischarge properties is investigated to understand their role on the CO2 conversion. Electrical measurements are carried out to explain the conversion trends and to characterize the microdischarges through their number, their lifetime, their intensity and the induced electrical charge. Their influence on the gas and electrode temperatures is also evidenced through optical emission spectroscopy and infrared imaging. It is shown that, in our configuration, the conversion depends mostly on the charge delivered in the plasma and not on the effective plasma voltage when the applied power is modified. Similarly, at constant total current, a better conversion is observed at low frequencies, where a less filamentary discharge regime with a higher effective plasma voltage than that at a higher frequency is obtained.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000372337900015	Publication Date	2016-02-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	40	Open Access
	Notes	The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A Ozkan would like to thank the financial support given by ‘Fonds David et Alice Van Buuren’. N Britun is a postdoctoral researcher of the F.R.S.-FNRS, Belgium.			Approved	Most recent IF: 3.302
	Call Number	c:irua:131904			Serial	4021
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	Author	Trenchev, G.; Kolev, S.; Bogaerts, A.
	Title	A 3D model of a reverse vortex flow gliding arc reactor			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	035014
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this computational study, a gliding arc plasma reactor with a reverse-vortex flow stabilization is modelled for the first time by a fluid plasma description. The plasma reactor operates with argon gas at atmospheric pressure. The gas flow is simulated using the k-ε Reynolds-averaged Navier–Stokes turbulent model. A quasi-neutral fluid plasma model is used for computing the plasma properties. The plasma arc movement in the reactor is observed, and the results for the gas flow, electrical characteristics, plasma density, electron temperature, and gas temperature are analyzed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000376557400022	Publication Date	2016-04-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	20	Open Access
	Notes	This research was carried out in the framework of the network on Physical Chemistry of Plasma–Surface Interactions— Interuniversity Attraction Poles, phase VII (http://psi-iap7.ulb. ac.be/), and supported by the Belgian Science Policy Office (BELSPO), and it was also funded by the Fund for Scientific Research Flanders (FWO). Grant number: 11U5316N.			Approved	Most recent IF: 3.302
	Call Number	c:irua:132888 c:irua:132888			Serial	4063
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	Author	Ozkan, A.; Dufour, T.; Bogaerts, A.; Reniers, F.
	Title	How do the barrier thickness and dielectric material influence the filamentary mode and CO₂conversion in a flowing DBD?			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	045016
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Dielectric barrier discharges (DBDs) are commonly used to generate cold plasmas at atmospheric pressure. Whatever their configuration (tubular or planar), the presence of a dielectric barrier is mandatory to prevent too much charge build up in the plasma and the formation of a thermal arc. In this article, the role of the barrier thickness (2.0, 2.4 and 2.8 mm) and of the kind of dielectric material (alumina, mullite, pyrex, quartz) is investigated on the filamentary behavior in the plasma and on the CO2 conversion in a tubular flowing DBD, by means of mass spectrometry measurements correlated with electrical characterization and IR imaging. Increasing the barrier thickness decreases the capacitance, while preserving the electrical charge. As a result, the voltage over the dielectric increases and a larger number of microdischarges is generated, which enhances the CO2 conversion. Furthermore, changing the dielectric material of the barrier, while keeping the same geometry and dimensions, also affects the CO2 conversion. The highest CO2 conversion and energy efficiency are obtained for quartz and alumina, thus not following the trend of the relative permittivity. From the electrical characterization, we clearly demonstrate that the most important parameters are the somewhat higher effective plasma voltage (yielding a somewhat higher electric field and electron energy in the plasma) for quartz, as well as the higher plasma current (and thus larger electron density) and the larger number of microdischarge filaments (mainly for alumina, but also for quartz). The latter could be correlated to the higher surface roughness for alumina and to the higher voltage over the dielectric for quartz.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000380380200030	Publication Date	2016-06-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	24	Open Access
	Notes	The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A. Ozkan would like to thank the financial support given by ‘Fonds David et Alice Van Buuren’.			Approved	Most recent IF: 3.302
	Call Number	c:irua:134396			Serial	4100
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	Author	Berthelot, A.; Bogaerts, A.
	Title	Modeling of plasma-based CO₂conversion: lumping of the vibrational levels			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	045022
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Although CO2 conversion by plasma technology is gaining increasing interest, the underlying mechanisms for an energy-efficient process are still far from understood. In this work, a reduced non-equilibrium CO2 plasma chemistry set, based on level lumping of the vibrational levels, is proposed and the reliability of this level-lumping method is tested by a self-consistent zero-dimensional code. A severe reduction of the number of equations to be solved is achieved, which is crucial to be able to model non-equilibrium CO2 plasmas by 2-dimensional models. Typical conditions of pressure and power used in a microwave plasma for CO2 conversion are investigated. Several different sets, using different numbers of lumped groups, are considered. The lumped models with 1, 2 or 3 groups are able to reproduce the gas temperature, electron density and electron temperature profiles, as calculated by the full model treating all individual excited levels, in the entire pressure range investigated. Furthermore, a 3-groups model is also able to reproduce the shape of the vibrational distribution function (VDF) and gives the most reliable prediction of the CO2 conversion. A strong influence of the vibrational excitation on the plasma characteristics is observed. Finally, the limitations of the lumped-levels method are discussed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000380380200036	Publication Date	2016-07-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	33	Open Access
	Notes	This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 606889 and it was also carried out in the framework of the network on Physical Chemistry of Plasma-Surface Interactions—Interuniversity Attraction Poles, phase VII (PSI-IAP7) supported by the Belgian Science Policy Office (BELSPO). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA.			Approved	Most recent IF: 3.302
	Call Number	c:irua:134397			Serial	4101
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	Author	Ozkan, A.; Dufour, T.; Silva, T.; Britun, N.; Snyders, R.; Reniers, F.; Bogaerts, A.
	Title	DBD in burst mode: solution for more efficient CO₂conversion?			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	055005
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	CO2 conversion into value-added products has gained significant interest over the few last years, as the greenhouse gas concentrations constantly increase due to anthropogenic activities. Here we report on experiments for CO2 conversion by means of a cold atmospheric plasma using a cylindrical flowing dielectric barrier discharge (DBD) reactor. A detailed comparison of this DBD ignited in a so-called burst mode (i.e. where an AC voltage is applied during a limited amount of time) and pure AC mode is carried out to evaluate their effect on the conversion of CO2 as well as on the energy efficiency. Decreasing the duty cycle in the burst mode from 100% (i.e. corresponding to pure AC mode) to 40% leads to a rise in the conversion from 16–26% and to a rise in the energy efficiency from 15 to 23%. Based on a detailed electrical analysis, we show that the conversion correlates with the features of the microfilaments. Moreover, the root-mean-square voltage in the burst mode remains constant as a function of the process time for the duty cycles <70%, while a higher duty cycle or the usual pure AC mode leads to a clear voltage decay by more than 500 V, over approximately 90 s, before reaching a steady state regime. The higher plasma voltage in the burst mode yields a higher electric field. This causes the increasing the electron energy, and therefore their involvement in the CO2 dissociation process, which is an additional explanation for the higher CO2 conversion and energy efficiency in the burst mode.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000403945500005	Publication Date	2016-08-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1361-6595	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	17	Open Access
	Notes	The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A. Ozkan would also like to thank financial support given by ‘Fonds David et Alice Van Buuren’.			Approved	Most recent IF: 3.302
	Call Number	c:irua:134841			Serial	4107
Permanent link to this record



	Author	Bogaerts, A.; Wang, W.; Berthelot, A.; Guerra, V.
	Title	Modeling plasma-based CO₂conversion: crucial role of the dissociation cross section			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	055016
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Plasma-based CO2 conversion is gaining increasing interest worldwide. A large research effort is devoted to improving the energy efficiency. For this purpose, it is very important to understand the underlying mechanisms of the CO2 conversion. The latter can be obtained by computer modeling, describing in detail the behavior of the various plasma species and all relevant chemical processes. However, the accuracy of the modeling results critically depends on the accuracy of the assumed input data, like cross sections. This is especially true for the cross section of electron impact dissociation, as the latter process is believed to proceed through electron impact excitation, but it is not clear from the literature which excitation channels effectively lead to dissociation. Therefore, the present paper discusses the effect of different electron impact dissociation cross sections reported in the literature on the calculated CO2 conversion, for a dielectric barrier discharge (DBD) and a microwave (MW) plasma. Comparison is made to experimental data for the DBD case, to elucidate which cross section might be the most realistic. This comparison reveals that the cross sections proposed by Itikawa and by Polak and Slovetsky both seem to underestimate the CO2 conversion. The cross sections recommended by Phelps with thresholds of 7 eV and 10.5 eV yield a CO2 conversion only slightly lower than the experimental data, but the sum of both cross sections overestimates the values, indicating that these cross sections represent dissociation, but most probably also include other (pure excitation) channels. Our calculations indicate that the choice of the electron impact dissociation cross section is crucial for the DBD, where this process is the dominant mechanism for CO2 conversion. In the MW plasma, it is only significant at pressures up to 100 mbar, while it is of minor importance for higher pressures, when dissociation proceeds mainly through collisions of CO2 with heavy particles.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000384030600001	Publication Date	2016-08-31
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1361-6595	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	57	Open Access
	Notes	The authors would like to thank R Snoeckx and S Heijkers for the interesting discussions. This research was supported by the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 606889, the European Marie Skłodowska-Curie Individual Fellowship project ‘GlidArc’ within Horizon2020, the FWO project (grant G.0383.16N), and the Network on Physical Chemistry of Plasma-Surface Interactions—Interuniversity Attraction Poles, phase VII (PSI-IAP7), supported by the Belgian Science Policy Office (BELSPO). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. VG was partially supported by the Portuguese FCT— Fundação para a Ci			Approved	Most recent IF: 3.302
	Call Number	c:irua:135070			Serial	4111
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	Author	Wang, W.; Bogaerts, A.
	Title	Effective ionisation coefficients and critical breakdown electric field of CO₂at elevated temperature: effect of excited states and ion kinetics			Type	A1 Journal article
	Year	2016	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	25	Issue	25	Pages	055025
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Electrical breakdown by the application of an electric field occurs more easily in hot gases than in cold gases because of the extra electron-species interactions that occur as a result of dissociation, ionization and excitation at higher temperature. This paper discusses some overlooked physics and clarifies inaccuracies in the evaluation of the effective ionization coefficients and the critical reduced breakdown electric field of CO2 at elevated temperature, considering the influence of excited states and ion kinetics. The critical reduced breakdown electric field is obtained by balancing electron generation and loss mechanisms using the electron energy distribution function (EEDF) derived from the Boltzmann transport equation under the two-term approximation. The equilibrium compositions of the hot gas mixtures are determined based on Gibbs free energy minimization considering the ground states as well as vibrationally and electronically excited states as independent species, which follow a Boltzmann distribution with a fixed excitation temperature. The interaction cross sections between electrons and the excited species, not reported previously, are properly taken into account. Furthermore, the ion kinetics, including electron–ion recombination, associative electron detachment, charge transfer and ion conversion into stable negative ion clusters, are also considered. Our results indicate that the excited species lead to a greater population of high-energy electrons at higher gas temperature and this affects the Townsend rate coefficients (i.e. of electron impact ionization and attachment), but the critical reduced breakdown electric field strength of CO2 is only affected when also properly accounting for the ion kinetics. Indeed, the latter greatly influences the effective ionization coefficients and hence the critical reduced breakdown electric field at temperatures above 1500 K. The rapid increase of the dissociative electron attachment cross-section of molecular oxygen with rising vibrational quantum number leads to a larger electron loss rate and this enhances the critical reduced breakdown electric field strength in the temperature range where the concentration of molecular oxygen is relatively high. The results obtained in this work show reasonable agreement with experimental results from literature, and are important for the evaluation of the dielectric strength of CO2 in a highly reactive environment at elevated temperature.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000385494000006	Publication Date	2016-09-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1361-6595	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	3	Open Access
	Notes	Skłodowska-Curie Individual Fellowship ‘GlidArc’ within Horizon2020 (Grant No.657304) and the FWO project (grant G.0383.16N). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @ c:irua:135515			Serial	4281
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