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	Author	Jia, W.-Z.; Zhang, Q.-Z.; Wang, X.-F.; Song, Y.-H.; Zhang, Y.-Y.; Wang, Y.-N.
	Title	Effect of dust particle size on the plasma characteristics in a radio frequency capacitively coupled silane plasma			Type	A1 Journal article
	Year	2019	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	52	Issue	1	Pages	015206
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Compared with dust-free plasmas, the existence of dust particles in plasmas may greatly influence the plasma properties. such as the plasma density, electron temperature, sheath properties, electron energy distribution function (EEDF) as well as the heating mechanism. In this work, a 1D hybrid fluid/MC model has been developed to investigate the interaction between dust and plasma in a low-pressure silane discharge sustained in a radio frequency capacitively coupled plasma, in which we assume spherical dust particles with a given radius are generated by taking the sum of the production rate of Si2H4- and Si2H5- as the nucleation rate. From our simulation, the plasma may experience definite perturbation by dust particles with a certain radius (more than 50nm) with an increase in electron temperature first, which further induces a rapid rise in the positive and negative ion densities. Then, the densities begin to decline due to the gradual lack of sufficient seed electrons. In addition, as the dust radius increases, the high energy tails of the EEDFs will be enhanced for discharge maintenance, accompanied by a decline in the population of low-energy electrons in comparison with those of pristine plasma. Furthermore, an obvious bulk heating is observed apart from the a-mode and local field reversal heating. This may contribute to the enhanced bulk electric field (also called the drift field) as a result of electron depletion via the dust. In addition, large-sized dust particles that accumulate near the sheaths tend to form two stable density peaks with their positions largely influenced by the time-averaged sheath thickness. A detailed study of the effects of the external parameters, including pressure, voltage and frequency, on the spatial distribution of dust particles is also conducted.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000448423800002	Publication Date	2018-10-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.588	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 2.588
	Call Number	UA @ admin @ c:irua:155361			Serial	5271
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	Author	Zhang, Q.-Z.; Wang, W.Z.; Thille, C.; Bogaerts, A.
	Title	H2S Decomposition into H2 and S2 by Plasma Technology: Comparison of Gliding Arc and Microwave Plasma			Type	A1 Journal article
	Year	2020	Publication	Plasma Chemistry And Plasma Processing	Abbreviated Journal	Plasma Chem Plasma P
	Volume	40	Issue	5	Pages	1163-1187
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	We studied hydrogen sulfide (H2S) decomposition into hydrogen (H2) and sulfur (S2) in a gliding arc plasmatron (GAP) and microwave (MW) plasma by a combination of 0D and 2D models. The conversion, energy efficiency, and plasma distribution are examined for different discharge conditions, and validated with available experiments from literature. Furthermore, a comparison is made between GAP and MW plasma. The GAP operates at atmospheric pressure, while the MW plasma experiments to which comparison is made were performed at reduced pressure. Indeed, the MW discharge region becomes very much contracted near atmospheric pressure, at the conditions under study, as revealed by our 2D model. The models predict that thermal reactions play the most important role in H2S decomposition in both plasma types. The GAP has a higher energy efficiency but lower conversion than the MW plasma at their typical conditions. When compared at the same conversion, the GAP exhibits a higher energy efficiency and lower energy cost than the MW plasma.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000543012200001	Publication Date	2020-06-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0272-4324	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.6	Times cited		Open Access
	Notes	This work was supported by the Scientific Research Foundation from Dalian University of Technology, DUT19RC(3)045. We gratefully acknowledge T. Godfroid (Materia Nova) for sharing the experimental data about the MW plasma. The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen.			Approved	Most recent IF: 3.6; 2020 IF: 2.355
	Call Number	PLASMANT @ plasmant @c:irua:172490			Serial	6409
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	Author	Zhang, Q.-Z.; Bogaerts, A.
	Title	Capacitive electrical asymmetry effect in an inductively coupled plasma reactor			Type	A1 Journal Article
	Year	2018	Publication	Plasma Sources Science & Technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	27	Issue	10	Pages	105019
	Keywords	A1 Journal Article; electrical asymmetry effect, inductively coupled plasma, self-bias, independent control of the ion fluxes and ion energy; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
	Abstract	The electrical asymmetry effect is realized by applying multiple frequency power sources (13.56 MHz and 27.12 MHz) to a capacitively biased substrate electrode in a specific inductively coupled plasma reactor. On the one hand, by adjusting the phase angle θ between the multiple frequency power sources, an almost linear self-bias develops on the substrate electrode, and consequently the ion energy can be well modulated, while the ion flux stays constant within a large range of θ. On the other hand, the plasma density and ion flux can be significantly modulated by tuning the inductive power supply, while only inducing a small change in the self- bias. Independent control of self-bias/ion energy and ion flux can thus be realized in this specific inductively coupled plasma reactor.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000448434100001	Publication Date	2018-10-26
	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	1	Open Access	Not_Open_Access
	Notes	We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604). This work was carried out in part using the Turing HPC infrastructure at 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 University of Antwerp.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @c:irua:155506			Serial	5069
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	Author	Sun, J.-Y.; Wen, D.-Q.; Zhang, Q.-Z.; Liu, Y.-X.; Wang, Y.-N.
	Title	The effects of electron surface interactions in geometrically symmetric capacitive RF plasmas in the presence of different electrode surface materials			Type	A1 Journal article
	Year	2019	Publication	Physics of plasmas	Abbreviated Journal	Phys Plasmas
	Volume	26	Issue	6	Pages	063505
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Particle-in-cell/Monte Carlo collision (PIC/MCC) simulations are performed to investigate the asymmetric secondary electron emission (SEE) effects when electrons strike two different material electrodes in low pressure capacitively coupled plasmas (CCPs). To describe the electron-surface interactions, a realistic model, considering the primary electron impact energy and angle, as well as the corresponding surface property-dependent secondary electron yields, is employed in PIC/MCC simulations. In this model, three kinds of electrons emitted from the surface are considered: (i) elastically reflected electrons, (ii) inelastically backscattered electrons, and (iii) electron induced secondary electrons (SEs, i.e., delta-electrons). Here, we examined the effects of electron-surface interactions on the ionization dynamics and plasma characteristics of an argon discharge. The discharge is driven by a voltage source of 13.56MHz with amplitudes in the range of 200-2000V. The grounded electrode material is copper (Cu) for all cases, while the powered electrode material is either Cu or silicon dioxide (SiO2). The simulations reveal that the electron impact-induced SEE is an essential process at low pressures, especially at high voltages. Different electrode materials result in an asymmetric response of SEE. Depending on the instantaneous local sheath potential and the phase of the SEE, these SEs either are reflected by the opposite sheath or strike the electrode surface, where they can induce delta-electrons upon their residual energies. It is shown that highly energetic delta-electrons contribute significantly to the ionization rate and a self-bias forms when the powered electrode material is assumed to be made of SiO2. Complex dynamics is observed due to the multiple electron-surface interaction processes and asymmetric yields of SEs in CCPs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000474440600043	Publication Date	2019-06-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1070-664x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.115	Times cited	1	Open Access
	Notes				Approved	Most recent IF: 2.115
	Call Number	UA @ admin @ c:irua:161353			Serial	6327
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	Author	Zhang, Q.-Z.; Tinck, S.; de Marneffe, J.-F.; Zhang, L.; Bogaerts, A.
	Title	Mechanisms for plasma cryogenic etching of porous materials			Type	A1 Journal article
	Year	2017	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	111	Issue	17	Pages	173104
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Porous materials are commonly used in microelectronics, as they can meet the demand for continuously shrinking electronic feature dimensions. However, they are facing severe challenges in plasma etching, due to plasma induced damage. In this paper, we present both the plasma characteristics and surface processing during the etching of porous materials. We explain how the damage occurs in the porous material during plasma etching for a wide range of chuck temperatures and the responsible mechanism for plasma damage-free etching at cryogenic temperature, by a combination of experiments and numerical modeling.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000413863400032	Publication Date	2017-10-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	2	Open Access	OpenAccess
	Notes	We acknowledge the support from Marie Skłodowska- Curie actions (Grant Agreement-702604). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the University of Antwerp. L. Zhang and J.-F. de Marneffe acknowledge Dr. M. Cooke and A. Goodyear from Oxford Instruments Plasma Technology for processing the samples at their Yatton facility in the United Kingdom.			Approved	Most recent IF: 3.411
	Call Number	PLASMANT @ plasmant @c:irua:147022			Serial	4762
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	Author	Wang, L.; Wen, D.-Q.; Zhang, Q.-Z.; Song, Y.-H.; Zhang, Y.-R.; Wang, Y.-N.
	Title	Disruption of self-organized striated structure induced by secondary electron emission in capacitive oxygen discharges			Type	A1 Journal article
	Year	2019	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	28	Issue	5	Pages	055007
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Self-organized striated structure has been observed experimentally and numerically in CF4 plasmas in radio-frequency capacitively coupled plasmas recently (Liu et al 2016 Phys. Rev. Lett. 116 255002). In this work, the striated structure is investigated in a capacitively coupled oxygen discharge with the introduction of the effect from the secondary electron emission, based on a particle-in-cell/Monte Carlo collision model. As we know, the transport of positive and negative ions plays a key role in the formation of striations in electronegative gases, for which, the electronegativity needs to be large enough. As the secondary electron emission increases, electrons in the sheaths gradually contribute more ionization to the discharge. Meanwhile, the increase of the electron density, especially in the plasma bulk, leads to an increased electrical conductivity and a reduced bulk electric field, which would shield the ions' mobility. These changes result in enlarged striation gaps. And then, with more emitted electrons, obvious disruption of the striations is observed accompanied with a transition of electron heating mode. Due to the weakened field, the impact ionization in the plasma bulk is attenuated, compared with the enhanced ionization caused by secondary electrons. This would lead to the electron heating mode transition from striated (STR) mode to gamma-mode. Besides, our investigation further reveals that gamma-mode is more likely to dominate the discharge under high gas pressures or driving voltages.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000467827800001	Publication Date	2019-04-09
	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	2	Open Access	Not_Open_Access: Available from 13.05.2020
	Notes				Approved	Most recent IF: 3.302
	Call Number	UA @ admin @ c:irua:160365			Serial	5270
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	Author	Zhang, Q.-Z.; Bogaerts, A.
	Title	Plasma streamer propagation in structured catalysts			Type	A1 Journal Article
	Year	2018	Publication	Plasma Sources Science & Technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	27	Issue	10	Pages	105013
	Keywords	A1 Journal Article; plasma catalysis, streamer propagation, 3D structures, PIC/MCC; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
	Abstract	Plasma catalysis is gaining increasing interest for various environmental applications. Catalytic material can be inserted in different shapes in the plasma, e.g., as pellets, (coated) beads, but also as honeycomb monolith and 3DFD structures, also called ‘structured catalysts’, which have high mass and heat transfer properties. In this work, we examine the streamer discharge propagation and the interaction between plasma and catalysts, inside the channels of such structured catalysts, by means of a two-dimensional particle-in-cell/Monte Carlo collision model. Our results reveal that plasma streamers behave differently in various structured catalysts. In case of a honeycomb structure, the streamers are limited to only one channel, with low or high plasma density when the channels are parallel or perpendicular to the electrodes, respectively. In contrast, in case of a 3DFD structure, the streamers can distribute to different channels, causing discharge enhancement due to surface charging on the dielectric walls of the structured catalyst, and especially giving rise to a broader plasma distribution. The latter should be beneficial for plasma catalysis applications, as it allows a larger catalyst surface area to be exposed to the plasma.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000448131900002	Publication Date	2018-10-22
	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	Not_Open_Access
	Notes	We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604). This work was carried out in part using the Turing HPC infrastructure at 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 University of Antwerp.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @c:irua:155510			Serial	5068
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	Author	Gu, J.-G.; Zhang, Y.; Gao, M.-X.; Wang, H.-Y.; Zhang, Q.-Z.; Yi, L.; Jiang, W.
	Title	Enhancement of surface discharge in catalyst pores in dielectric barrier discharges			Type	A1 Journal article
	Year	2019	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	125	Issue	15	Pages	153303
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The generation of high-density plasmas on the surface of porous catalysts is very important for plasma catalysis, as it determines the active surface of the catalyst that is available for the reaction. In this work, we investigate the mechanism of surface and volume plasma streamer formation and propagation near micro-sized pores in dielectric barrier discharges operating in air at atmospheric pressure. A two-dimensional particle-in-cell/ Monte Carlo collision model is used to model the individual kinetic behavior of plasma species. Our calculations indicate that the surface discharge is enhanced on the surface of the catalyst pores compared with the microdischarge inside the catalyst pores. The reason is that the surface ionization wave induces surface charging along the catalyst pore sidewalls, leading to a strong electric field along the pore sidewalls, which in turn further enhances the surface discharge. Therefore, highly concentrated reactive species occur on the surfaces of the catalyst pores, indicating high-density plasmas on the surface of porous catalysts. Indeed, the maximum electron impact excitation and ionization rates occur on the pore surface, indicating the more pronounced production of excited state and electron-ion pairs on the pore surface than inside the pore, which may profoundly affect the plasma catalytic process. Published under license by AIP Publishing.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000465441200022	Publication Date	2019-04-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979; 1089-7550	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	4	Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 2.068
	Call Number	UA @ admin @ c:irua:160397			Serial	5273
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	Author	Bogaerts, A.; Zhang, Q.-Z.; Zhang, Y.-R.; Van Laer, K.; Wang, W.
	Title	Burning questions of plasma catalysis: Answers by modeling			Type	A1 Journal article
	Year	2019	Publication	Catalysis today	Abbreviated Journal	Catal Today
	Volume	337	Issue		Pages	3-14
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Plasma catalysis is promising for various environmental, energy and chemical synthesis applications, but the underlying mechanisms are far from understood. Modeling can help to obtain a better insight in these mechanisms. Some burning questions relate to the plasma behavior inside packed bed reactors and whether plasma can penetrate into catalyst pores. In this paper, we try to provide answers to these questions, by means of both ﬂuid modeling and particle-in-cell/Monte Carlo collision simulations. We present a short overview of recent ﬁndings obtained in our group by means of modeling, i.e., the enhanced electric ﬁeld near the contact points and the streamer propagation through the packing in packed bed reactors, as well as the plasma behavior in catalyst pores, to determine the minimum pore size in which plasma streamers can penetrate.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000482179500002	Publication Date	2019-04-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0920-5861	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.636	Times cited	7	Open Access
	Notes	University of Antwerp, the European Marie Skłodowska-Curie Individual Fellowships “GlidArc”; “CryoEtch” within Horizon2020, 657304 702604 ;We would like to thank H.-H. Kim for performing experiments to validate the modeling of streamer propagation in packed bed reactors. We acknowledge ﬁnancial support from the TOP-BOF project of the University of Antwerp, the European Marie Skłodowska-Curie Individual Fellowships “GlidArc” and “CryoEtch” within Horizon2020 (Grant Nos. 657304 and 702604).			Approved	Most recent IF: 4.636
	Call Number	PLASMANT @ plasmant @c:irua:161775			Serial	5356
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	Author	Wen, D.-Q.; Zhang, Q.-Z.; Jiang, W.; Song, U.-H.; Bogaerts, A.; Wang, Y.-N.
	Title	Phase modulation in pulsed dual-frequency capacitively coupled plasmas			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	115	Issue	23	Pages	233303
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Particle-in-cell/Monte Carlo collision simulations, coupled with an external circuit, are used to investigate the behavior of pulsed dual-frequency (DF) capacitively coupled plasmas (CCPs). It is found that the phase shift θ between the high (or low) frequency source and the pulse modulation has a great influence on the ion density and the ionization rate. By pulsing the high frequency source, the time-averaged ion density shows a maximum when θ = 90∘. The time-averaged ion energy distribution functions (IEDFs) at the driven electrode, however, keep almost unchanged, illustrating the potential of pulsed DF-CCP for independent control of ion density (and flux) and ion energy. A detailed investigation of the temporal evolution of the plasma characteristics indicates that several high frequency harmonics can be excited at the initial stage of a pulse period by tuning the phase shift θ, and this gives rise to strong sheath oscillations, and therefore high ionization rates. For comparison, the pulsing of the low frequency source is also studied. In this case, the ion density changes slightly as a function of time, and the time-averaged ion density shows the same trend as in the HF modulation for different phase shifts θ. Moreover, the time-averaged IEDFs at the driven electrode can be modulated, showing the potential to reduce the maximum ion bombardment energy.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000338106000008	Publication Date	2014-06-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;1089-7550;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	8	Open Access
	Notes				Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:117415			Serial	2585
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	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
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	Author	Zhang, Q.-Z.; Wang, Y.-N.; Bogaerts, A.
	Title	Heating mode transition in a hybrid direct current/dual-frequency capacitively coupled CF₄ discharge			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	115	Issue	22	Pages	223302-223306
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Computer simulations based on the particle-in-cell/Monte Carlo collision method are performed to study the plasma characteristics and especially the transition in electron heating mechanisms in a hybrid direct current (dc)/dual-frequency (DF) capacitively coupled CF 4 discharge. When applying a superposed dc voltage, the plasma density first increases, then decreases, and finally increases again, which is in good agreement with experiments. This trend can be explained by the transition between the four main heating modes, i.e., DF coupling, dc and DF coupling, dc source dominant heating, and secondary electron dominant heating.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000337891800006	Publication Date	2014-06-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;1089-7550;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	9	Open Access
	Notes				Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:117347			Serial	1414
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	Author	Zhang, Q.-Z.; Wang, W.-Z.; Bogaerts, A.
	Title	Importance of surface charging during plasma streamer propagation in catalyst pores			Type	A1 Journal article
	Year	2018	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	27	Issue	6	Pages	065009
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Plasma catalysis is gaining increasing interest, but the underlying mechanisms are far from understood. Different catalyst materials will have different chemical effects, but in addition, they might also have different dielectric constants, which will affect surface charging, and thus the plasma behavior. In this work, we demonstrate that surface charging plays an important role in the streamer propagation and discharge enhancement inside catalyst pores, and in the plasma distribution along the dielectric surface, and this role greatly depends on the dielectric constant of the material. For εr50, surface charging causes the plasma to spread along the dielectric surface and inside the pores, leading to deeper plasma streamer penetration, while for εr>50 or for metallic coatings, the discharge is more localized, due to very weak surface charging. In addition, at εr=50, the significant surface charge density near the pore entrance causes a large potential drop at the sharp pore edges, which induces a strong electric field and results in most pronounced plasma enhancement near the pore entrance.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000436845700002	Publication Date	2018-06-27
	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	13	Open Access	OpenAccess
	Notes	We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the TOP-BOF project of the University of Antwerp. This work was carried out in part using the Turing HPC infrastructure at 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 University of Antwerp.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @c:irua:152243			Serial	4995
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	Author	Zhang, Q.-Z.; Bogaerts, A.
	Title	Propagation of a plasma streamer in catalyst pores			Type	A1 Journal article
	Year	2018	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	27	Issue	3	Pages	035009
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Although plasma catalysis is gaining increasing interest for various environmental applications, the underlying mechanisms are still far from understood. For instance, it is not yet clear whether and how plasma streamers can propagate in catalyst pores, and what is the minimum pore size to make this happen. As this is crucial information to ensure good plasma-catalyst interaction, we study here the mechanism of plasma streamer propagation in a catalyst pore, by means of a twodimensional particle-in-cell/Monte Carlo collision model, for various pore diameters in the nm range to μm-range. The so-called Debye length is an important criterion for plasma penetration into catalyst pores, i.e. a plasma streamer can penetrate into pores when their diameter is larger than the Debye length. The Debye length is typically in the order of a few 100 nm up to 1 μm at the conditions under study, depending on electron density and temperature in the plasma streamer. For pores in the range of ∼50 nm, plasma can thus only penetrate to some extent and at very short times, i.e. at the beginning of a micro-discharge, before the actual plasma streamer reaches the catalyst surface and a sheath is formed in front of the surface. We can make plasma streamers penetrate into smaller pores (down to ca. 500 nm at the conditions under study) by increasing the applied voltage, which yields a higher plasma density, and thus reduces the Debye length. Our simulations also reveal that the plasma streamers induce surface charging of the catalyst pore sidewalls, causing discharge enhancement inside the pore, depending on pore diameter and depth.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000427976800001	Publication Date	2018-03-20
	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	16	Open Access	OpenAccess
	Notes	We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the Fund for Scientific Research Flanders (FWO) (Excellence of Science Program; EOS ID 30505023). This work was carried out in part using the Turing HPC infrastructure at 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 University of Antwerp.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @c:irua:150877			Serial	4954
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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
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	Author	Zhang, Q.-Z.; Zhao, S.-X.; Jiang, W.; Wang, Y.-N.
	Title	Separate control between geometrical and electrical asymmetry effects in capacitively coupled plasmas			Type	A1 Journal article
	Year	2012	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	45	Issue	30	Pages	305203
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Both geometrical and electrical asymmetry effects in capacitive argon discharges are investigated using a two-dimensional particle-in-cell coupled with Monte Carlo collision model. When changing the ratio of the top and bottom electrode surface areas and the phase shift between the two applied harmonics, the induced self-bias was found to develop separately. By adjusting the ratio between the high and low harmonic amplitudes, the electrical asymmetry effect at a fixed phase shift can be substantially optimized. However, the self-bias caused by the geometrical asymmetry hardly changed. Moreover, the separate control of these two asymmetry effects can also be demonstrated from their power absorption profiles. Both the axial and radial plasma density distributions can be modulated by the electrical asymmetry effect.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000306475200007	Publication Date	2012-07-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727;1361-6463;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.588	Times cited	20	Open Access
	Notes				Approved	Most recent IF: 2.588; 2012 IF: 2.528
	Call Number	UA @ lucian @ c:irua:100751			Serial	2984
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	Author	Liu, Y.-X.; Zhang, Q.-Z.; Liu, J.; Song, Y.-H.; Bogaerts, A.; Wang, Y.-N.
	Title	Effect of bulk electric field reversal on the bounce resonance heating in dual-frequency capacitively coupled electronegative plasmas			Type	A1 Journal article
	Year	2012	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	101	Issue	11	Pages	114101
	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 and argon has been studied by different experimental methods. In comparison with the electropositive argon discharge, the BRH in an electronegative discharge occurs at larger electrode gaps. Kinetic particle simulations reveal 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 resonant electrons when traversing the bulk, resulting in a suppressed BRH. This effect becomes more pronounced at lower high-frequency power, when the discharge mode changes from electropositive to electronegative.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000309329300094	Publication Date	2012-09-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	26	Open Access
	Notes				Approved	Most recent IF: 3.411; 2012 IF: 3.794
	Call Number	UA @ lucian @ c:irua:100637			Serial	802
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