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	Author	Li, D.Y.; Zeng, Y.J.; Pereira, L.M.C.; Batuk, D.; Hadermann, J.; Zhang, Y.Z.; Ye, Z.Z.; Temst, K.; Vantomme, A.; Van Bael, M.J.; Van Haesendonck, C.;
	Title	Anisotropic magnetism and spin-dependent transport in Co nanoparticle embedded ZnO thin films			Type	A1 Journal article
	Year	2013	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	114	Issue	3	Pages	033909-6
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Oriented Co nanoparticles were obtained by Co ion implantation in crystalline ZnO thin films grown by pulsed laser deposition. Transmission electron microscopy revealed the presence of elliptically shaped Co precipitates with nanometer size, which are embedded in the ZnO thin films, resulting in anisotropic magnetic behavior. The low-temperature resistance of the Co-implanted ZnO thin films follows the Efros-Shklovskii type variable-range-hopping. Large negative magnetoresistance (MR) exceeding 10% is observed in a magnetic field of 1 T at 2.5K and the negative MR survives up to 250K (0.3%). The negative MR reveals hysteresis as well as anisotropy that correlate well with the magnetic properties, clearly demonstrating the presence of spin-dependent transport. (C) 2013 AIP Publishing LLC.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000322202700071	Publication Date	2013-07-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	10	Open Access
	Notes				Approved	Most recent IF: 2.068; 2013 IF: 2.185
	Call Number	UA @ lucian @ c:irua:110765			Serial	126
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	Author	Zhao, S.-X.; Zhang, Y.-R.; Gao, F.; Wang, Y.-N.; Bogaerts, A.
	Title	Bulk plasma fragmentation in a C₄F₈ inductively coupled plasma : a hybrid modelling study			Type	A1 Journal article
	Year	2015	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	117	Issue	117	Pages	243303
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A hybrid model is used to investigate the fragmentation of C4F8 inductive discharges. Indeed, the resulting reactive species are crucial for the optimization of the Si-based etching process, since they determine the mechanisms of fluorination, polymerization, and sputtering. In this paper, we present the dissociation degree, the density ratio of F vs. CxFy (i.e., fluorocarbon (fc) neutrals), the neutral vs. positive ion density ratio, details on the neutral and ion components, and fractions of various fc neutrals (or ions) in the total fc neutral (or ion) density in a C4F8 inductively coupled plasma source, as well as the effect of pressure and power on these results. To analyze the fragmentation behavior, the electron density and temperature and electron energy probability function (EEPF) are investigated. Moreover, the main electron-impact generation sources for all considered neutrals and ions are determined from the complicated C4F8 reaction set used in the model. The C4F8 plasma fragmentation is explained, taking into account many factors, such as the EEPF characteristics, the dominance of primary and secondary processes, and the thresholds of dissociation and ionization. The simulation results are compared with experiments from literature, and reasonable agreement is obtained. Some discrepancies are observed, which can probably be attributed to the simplified polymer surface kinetics assumed in the model.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000357613900009	Publication Date	2015-06-30
	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	11	Open Access
	Notes				Approved	Most recent IF: 2.068; 2015 IF: 2.183
	Call Number	c:irua:126477			Serial	261
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	Author	Zhang, Y.-R.; Xu, X.; Zhao, S.-X.; Bogaerts, A.; Wang, Y.-N.
	Title	Comparison of electrostatic and electromagnetic simulations for very high frequency plasmas			Type	A1 Journal article
	Year	2010	Publication	Physics of plasmas	Abbreviated Journal	Phys Plasmas
	Volume	17	Issue	11	Pages	113512-113512,11
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional self-consistent fluid model combined with the full set of Maxwell equations is developed to investigate an argon capacitively coupled plasma, focusing on the electromagnetic effects on the discharge characteristics at various discharge conditions. The results indicate that there exist distinct differences in plasma characteristics calculated with the so-called electrostatic model (i.e., without taking into account the electromagnetic effects) and the electromagnetic model (which includes the electromagnetic effects), especially at very high frequencies. Indeed, when the excitation source is in the high frequency regime and the electromagnetic effects are taken into account, the plasma density increases significantly and meanwhile the ionization rate evolves to a very different distribution when the electromagnetic effects are dominant. Furthermore, the dependence of the plasma characteristics on the voltage and pressure is also investigated, at constant frequency. It is observed that when the voltage is low, the difference between these two models becomes more obvious than at higher voltages. As the pressure increases, the plasma density profiles obtained from the electromagnetic model smoothly shift from edge-peaked over uniform to a broad maximum in the center. In addition, the edge effect becomes less pronounced with increasing frequency and pressure, and the skin effect rather than the standing-wave effect becomes dominant when the voltage is high.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Woodbury, N.Y.	Editor
	Language		Wos	000285486500105	Publication Date	2010-11-22
	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	30	Open Access
	Notes				Approved	Most recent IF: 2.115; 2010 IF: 2.320
	Call Number	UA @ lucian @ c:irua:84763			Serial	429
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	Author	Zhang, Y.; Jiang, W.; Zhang, Q.Z.; Bogaerts, A.
	Title	Computational study of plasma sustainability in radio frequency micro-discharges			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	115	Issue	19	Pages	193301-193311
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	We apply an implicit particle-in-cell Monte-Carlo (PIC-MC) method to study a radio-frequency argon microdischarge at steady state in the glow discharge limit, in which the microdischarge is sustained by secondary electron emission from the electrodes. The plasma density, electron energy distribution function (EEDF), and electron temperature are calculated in a wide range of operating conditions, including driving voltage, microdischarge gap, and pressure. Also, the effect of gap size scaling (in the range of 50-1000 μm) on the plasma sustaining voltage and peak electron density at atmospheric pressure is examined, which has not been explored before. In our simulations, three different EEDFs, i.e., a so-called three temperature hybrid mode, a two temperature α mode, and a two temperature γ mode distribution, are identified at different gaps and voltages. The maximum sustaining voltage to avoid a transition from the glow mode to an arc is predicted, as well as the minimum sustaining voltage for a steady glow discharge. Our calculations elucidate that secondary electrons play an essential role in sustaining the discharge, and as a result the relationship between breakdown voltage and gap spacing is far away from the Paschen law at atmospheric pressure.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000336920200010	Publication Date	2014-05-16
	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	11	Open Access
	Notes				Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:116948			Serial	458
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	Author	Liu, Y.-X.; Zhang, Y.-R.; Bogaerts, A.; Wang, Y.-N.
	Title	Electromagnetic effects in high-frequency large-area capacitive discharges : a review			Type	A1 Journal article
	Year	2015	Publication	Journal of vacuum science and technology: A: vacuum surfaces and films	Abbreviated Journal	J Vac Sci Technol A
	Volume	33	Issue	33	Pages	020801
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In traditional capacitively coupled plasmas, the discharge can be described by an electrostatic model, in which the Poisson equation is employed to determine the electrostatic electric field. However, current plasma reactors are much larger and driven at a much higher frequency. If the excitation wavelength k in the plasma becomes comparable to the electrode radius, and the plasma skin depth d becomes comparable to the electrode spacing, the electromagnetic (EM) effects will become significant and compromise the plasma uniformity. In this regime, capacitive discharges have to be described by an EM model, i.e., the full set of Maxwells equations should be solved to address the EM effects. This paper gives an overview of the theory, simulation and experiments that have recently been carried out to understand these effects, which cause major uniformity problems in plasma processing for microelectronics and flat panel display industries. Furthermore, some methods for improving the plasma uniformity are also described and compared.
	Address
	Corporate Author				Thesis
	Publisher	A v s amer inst physics	Place of Publication	Melville	Editor
	Language		Wos	000355739500007	Publication Date	2015-02-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0734-2101;1520-8559;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.374	Times cited	10	Open Access
	Notes				Approved	Most recent IF: 1.374; 2015 IF: 2.322
	Call Number	c:irua:123541			Serial	903
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	Author	Zhang, Y.-R.; Gao, F.; Li, X.-C.; Bogaerts, A.; Wang, Y.-N.
	Title	Fluid simulation of the bias effect in inductive/capacitive discharges			Type	A1 Journal article
	Year	2015	Publication	Journal of vacuum science and technology: A: vacuum surfaces and films	Abbreviated Journal	J Vac Sci Technol A
	Volume	33	Issue	33	Pages	061303
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Computer simulations are performed for an argon inductively coupled plasma (ICP) with a capacitive radio-frequency bias power, to investigate the bias effect on the discharge mode transition and on the plasma characteristics at various ICP currents, bias voltages, and bias frequencies. When the bias frequency is fixed at 13.56 MHz and the ICP current is low, e.g., 6A, the spatiotemporal averaged plasma density increases monotonically with bias voltage, and the bias effect is already prominent at a bias voltage of 90 V. The maximum of the ionization rate moves toward the bottom electrode, which indicates clearly the discharge mode transition in inductive/capacitive discharges. At higher ICP currents, i.e., 11 and 13 A, the plasma density decreases first and then increases with bias voltage, due to the competing mechanisms between the ion acceleration power dissipation and the capacitive power deposition. At 11 A, the bias effect is still important, but it is noticeable only at higher bias voltages. At 13 A, the ionization rate is characterized by a maximum at the reactor center near the dielectric window at all selected bias voltages, which indicates that the ICP power, instead of the bias power, plays a dominant role under this condition, and no mode transition is observed. Indeed, the ratio of the bias power to the total power is lower than 0.4 over a wide range of bias voltages, i.e., 0300V. Besides the effect of ICP current, also the effect of various bias frequencies is investigated. It is found that the modulation of the bias power to the spatiotemporal distributions of the ionization rate at 2MHz is strikingly different from the behavior observed at higher bias frequencies. Furthermore, the minimum of the plasma density appears at different bias voltages, i.e., 120V at 2MHz and 90V at 27.12 MHz.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000365503800020	Publication Date	2015-08-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0734-2101;1520-8559;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.374	Times cited	9	Open Access
	Notes				Approved	Most recent IF: 1.374; 2015 IF: 2.322
	Call Number	c:irua:126824			Serial	1229
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	Author	Zhang, Y.-R.; Xu, X.; Bogaerts, A.; Wang, Y.-N.
	Title	Fluid simulation of the phase-shift effect in hydrogen capacitively coupled plasmas: 1 : transient behaviour of electrodynamics and power deposition			Type	A1 Journal article
	Year	2012	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	45	Issue	1	Pages	015202-015202,11
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional self-consistent fluid model coupled with the full set of Maxwell equations is established to investigate the phase-shift effect on the transient behaviour of electrodynamics and power deposition in a hydrogen capacitively coupled plasma. The effect has been examined at 13.56 MHz and 100 MHz, respectively, because of the different phase-shift modulation when the electromagnetic effects are dominant. The results indicate that the spatiotemporal distributions of the plasma characteristics obtained for various phase-shift cases are obviously different both in shape and especially in absolute values. Indeed, when the phase difference varies from 0 to π, there is an increase in the electron flux, thus the power deposition becomes more pronounced. At the frequency of 13.56 MHz, the axial electron flux in the bulk plasma becomes uniform along the z-axis, and the radial electron flux exhibits two peaks within one period at the reverse-phase case, whereas the oscillation is less pronounced at the in-phase case. Furthermore, in the very high frequency discharge, the radial electron flux is alternately positive and negative with four peaks during one period, and the ionization mainly occurs in the sheath region, due to the prominent power deposition there at a phase difference equal to π.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000298290000011	Publication Date	2011-12-12
	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	57	Open Access
	Notes				Approved	Most recent IF: 2.588; 2012 IF: 2.528
	Call Number	UA @ lucian @ c:irua:92851			Serial	1230
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	Author	Zhang, Y.-R.; Xu, X.; Bogaerts, A.; Wang, Y.-N.
	Title	Fluid simulation of the phase-shift effect in hydrogen capacitively coupled plasmas: 2 : radial uniformity of the plasma characteristics			Type	A1 Journal article
	Year	2012	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	45	Issue	1	Pages	015203-015203,13
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional fluid model, including the full set of Maxwell equations, has been developed and applied to investigate the effect of a phase shift between two power sources on the radial uniformity of several plasma characteristics in a hydrogen capacitively coupled plasma. This study was carried out at various frequencies in the range 13.56200 MHz. When the frequency is low, at 13.56 MHz, the plasma density is characterized by an off-axis peak when both power sources are in-phase (phgr = 0), and the best radial uniformity is obtained at phgr = π. This trend can be explained because the radial nonuniformity caused by the electrostatic edge effect can be effectively suppressed by the phase-shift effect at a phase difference equal to π. When the frequency rises to 60 MHz, the plasma density profiles shift smoothly from edge-peaked over uniform to centre-peaked as the phase difference increases, due to the pronounced standing-wave effect, and the best radial uniformity is reached at phgr = 0.3π. At a frequency of 100 MHz, a similar behaviour is observed, except that the maximum of the plasma density moves again towards the radial edge at the reverse-phase case (phgr = π), because of the dominant skin effect. When the frequency is 200 MHz, the bulk plasma density increases significantly with increasing phase-shift values, and a better uniformity is obtained at phgr = 0.4π. This is because the density in the centre increases faster than at the radial edge as the phase difference rises, due to the increasing power deposition Pz in the centre and the decreasing power density Pr at the radial edge. As the phase difference increases to π, the maximum near the radial edge becomes obvious again. This is because the skin effect has a predominant influence on the plasma density under this condition, resulting in a high density at the radial edge. Moreover, the axial ion flux increases monotonically with phase difference, and exhibits similar profiles to the plasma density. The calculation results illustrate that the radial uniformity of the various plasma characteristics is strongly dependent on the applied frequency and the phase shift between both power sources, which is important to realize, for controlling the uniformity of the plasma etch and deposition processes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000298290000012	Publication Date	2011-12-12
	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	15	Open Access
	Notes				Approved	Most recent IF: 2.588; 2012 IF: 2.528
	Call Number	UA @ lucian @ c:irua:92852			Serial	1231
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	Author	Zhang, Y.-R.; Bogaerts, A.; Wang, Y.-N.
	Title	Fluid simulation of the phase-shift effect in Ar/CF₄ 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	48	Pages	485204
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional self-consistent fluid model combined with the full set of Maxwell equations is employed to investigate an Ar/CF4 capacitively coupled plasma, focusing on the phase-shift effect on the plasma characteristics at various frequencies and gas mixture ratios. When the discharge is sustained by a single frequency at 13.56 MHz in an Ar/CF4 mixture with a ratio of 0.9/0.1, no obvious difference is detected between the electron densities obtained in the so-called electrostatic model (with only the static electric fields taken into account) and the electromagnetic model (which includes the electromagnetic effects). However, as the frequency increases to 60 and 100 MHz, the difference becomes distinct, due to the significant influence of the electromagnetic effects. The phase-shift effect on the plasma radial uniformity has also been investigated in a dual frequency discharge, i.e. when the top driven source is switched on with a phase difference phiv ranging from 0 to π, in the frequency range 13.56100 MHz. At low concentration of CF4 (10%), Ar+ ions are the major positive ions in the entire range of frequencies. When the frequency is low, i.e. 13.56 MHz, the Ar+ density exhibits an off-axis peak at phiv = 0 due to the edge effect, and a better uniformity caused by the phase-shift modulation is obtained at phiv = π. At 60 MHz, the Ar+ density varies from edge-peaked at phiv = 0 to uniform (i.e. at phiv = 0.53π), and finally at phiv = π, a broad maximum is observed at the centre due to the standing-wave effect. As the frequency increases to 100 MHz, the best radial uniformity is reached at 0.25π, and the maximum moves again towards the radial wall in the reverse-phase case (phiv = π) due to the dominant skin effect. When the frequency is fixed at 100 MHz, the phase-shift control shows a different behaviour at a high concentration of CF4. For instance, the ${\rm CF}_3
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000311148300011	Publication Date	2012-11-06
	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	8	Open Access
	Notes				Approved	Most recent IF: 2.588; 2012 IF: 2.528
	Call Number	UA @ lucian @ c:irua:101754			Serial	1232
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	Author	Zhang, Y.; Jiang, W.; Bogaerts, A.
	Title	Kinetic simulation of direct-current driven microdischarges in argon at atmospheric pressure			Type	A1 Journal article
	Year	2014	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	47	Issue	43	Pages	435201
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A one-dimensional, implicit particle-in-cell Monte Carlo collision model is used to simulate the plasma kinetic properties at a steady state in a parallel-plate direct current argon glow microdischarge under various operating conditions, such as driving voltage (301000 V) and gap size (101000 µm) at atmospheric pressure. First, a comparison between rf and dc modes is shown for the same pressure, driving voltage and gap spacing. Furthermore, the effect of gap size scaling (in the range of 101000 µm) on the breakdown voltage, peak electron density and peak electron current density at the breakdown voltage is examined. The breakdown voltage is lower than 150 V in all gaps considered. The microdischarge is found to have a neutral bulk plasma region and a cathode sheath region with size varying with the applied voltage and the discharge gap. In our calculations, the electron and ion densities are of the order of 10181023 m−3, which is in the glow discharge limit, as the ionization degree is lower than 1% . The electron energy distribution function shows a two-energy group distribution at a gap of 10 µm and a three-energy group distribution at larger gaps such as 200 µm and 1000 µm, emphasizing the importance of the gap spacing in dc microdischarges.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000343150500011	Publication Date	2014-10-03
	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	10	Open Access
	Notes				Approved	Most recent IF: 2.588; 2014 IF: 2.721
	Call Number	UA @ lucian @ c:irua:119152			Serial	1759
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	Author	Zhang, Y.-R.; Tinck, S.; De Schepper, P.; Wang, Y.-N.; Bogaerts, A.
	Title	Modeling and experimental investigation of the plasma uniformity in CF₄/O₂ capacitively coupled plasmas, operating in single frequency and dual frequency regime			Type	A1 Journal article
	Year	2015	Publication	Journal of vacuum science and technology: A: vacuum surfaces and films	Abbreviated Journal	J Vac Sci Technol A
	Volume	33	Issue	33	Pages	021310
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional hybrid Monte Carlofluid model, incorporating a full-wave solution of Maxwell's equations, is employed to describe the behavior of high frequency (HF) and very high frequency capacitively coupled plasmas (CCPs), operating both at single frequency (SF) and dual frequency (DF) in a CF4/O2 gas mixture. First, the authors investigate the plasma composition, and the simulations reveal that besides CF4 and O2, also COF2, CF3, and CO2 are important neutral species, and CF+3 and F− are the most important positive and negative ions. Second, by comparing the results of the model with and without taking into account the electromagnetic effects for a SF CCP, it is clear that the electromagnetic effects are important, both at 27 and 60 MHz, because they affect the absolute values of the calculation results and also (to some extent) the spatial profiles, which accordingly affects the uniformity in plasma processing. In order to improve the plasma radial uniformity, which is important for the etch process, a low frequency (LF) source is added to the discharge. Therefore, in the major part of the paper, the plasma uniformity is investigated for both SF and DF CCPs, operating at a HF of 27 and 60 MHz and a LF of 2 MHz. For this purpose, the authors measure the etch rates as a function of position on the wafer in a wide range of LF powers, and the authors compare them with the calculated fluxes toward the wafer of the plasma species playing a role in the etch process, to explain the trends in the measured etch rate profiles. It is found that at a HF of 60 MHz, the uniformity of the etch rate is effectively improved by adding a LF power of 2 MHz and 300 W, while its absolute value increases by about 50%, thus a high etch rate with a uniform distribution is observed under this condition.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000355739500026	Publication Date	2015-01-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0734-2101;1520-8559;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.374	Times cited	3	Open Access
	Notes				Approved	Most recent IF: 1.374; 2015 IF: 2.322
	Call Number	c:irua:122650			Serial	2107
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	Author	Jiang, W.; Zhang, Y.; Bogaerts, A.
	Title	Numerical characterization of local electrical breakdown in sub-micrometer metallized film capacitors			Type	A1 Journal article
	Year	2014	Publication	New journal of physics	Abbreviated Journal	New J Phys
	Volume	16	Issue		Pages	113036
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In metallized film capacitors, there exists an air gap of about 0.2 μm between the films, with a pressure ranging generally from 130 atm. Because of the created potential difference between the two films, a microdischarge is formed in this gap. In this paper, we use an implicit particle-in-cell Monte Carlo collision simulation method to study the discharge properties in this direct-current microdischarge with 0.2 μm gap in a range of different voltages and pressures. The discharge process is significantly different from a conventional high pressure discharge. Indeed, the high electric field due to the small gap sustains the discharge by field emission. At low applied voltage (~15 V), only the electrons are generated by field emission, while both electrons and ions are generated as a stable glow discharge at medium applied voltage (~50 V). At still higher applied voltage (~100 V), the number of electrons and ions rapidly multiplies, the electric field reverses, and the discharge changes from a glow to an arc regime.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos	000346763400006	Publication Date	2014-11-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1367-2630;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.786	Times cited		Open Access
	Notes				Approved	Most recent IF: 3.786; 2014 IF: 3.558
	Call Number	UA @ lucian @ c:irua:120455			Serial	2393
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	Author	Zhang, Y.; Fischetti, M.V.; Sorée, B.; Magnus, W.; Heyns, M.; Meuris, M.
	Title	Physical modeling of strain-dependent hole mobility in Ge p-channel inversion layers			Type	A1 Journal article
	Year	2009	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	106	Issue	8	Pages	083704,1-083704,9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We present comprehensive calculations of the low-field hole mobility in Ge p-channel inversion layers with SiO2 insulator using a six-band k·p band-structure model. The cases of relaxed, biaxially, and uniaxially (both tensily and compressively) strained Ge are studied employing an efficient self-consistent methodmaking use of a nonuniform spatial mesh and of the Broyden second methodto solve the coupled envelope-wave function k·p and Poisson equations. The hole mobility is computed using the KuboGreenwood formalism accounting for nonpolar hole-phonon scattering and scattering with interfacial roughness. Different approximations to handle dielectric screening are also investigated. As our main result, we find a large enhancement (up to a factor of 10 with respect to Si) of the mobility in the case of uniaxial compressive stress similarly to the well-known case of Si. Comparison with experimental data shows overall qualitative agreement but with significant deviations due mainly to the unknown morphology of the rough Ge-insulator interface, to additional scattering with surface optical phonon from the high- insulator, to Coulomb scattering interface traps or oxide chargesignored in our calculationsand to different channel structures employed.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000271358100050	Publication Date	2009-10-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	29	Open Access
	Notes				Approved	Most recent IF: 2.068; 2009 IF: 2.072
	Call Number	UA @ lucian @ c:irua:80137			Serial	2617
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	Author	Zhang, Y.; Wang, H.-yu; Jiang, W.; Bogaerts, A.
	Title	Two-dimensional particle-in cell/Monte Carlo simulations of a packed-bed dielectric barrier discharge in air at atmospheric pressure			Type	A1 Journal article
	Year	2015	Publication	New journal of physics	Abbreviated Journal	New J Phys
	Volume	17	Issue	17	Pages	083056
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The plasma behavior in a parallel-plate dielectric barrier discharge (DBD) is simulated by a two-dimensional particle-in-cell/Monte Carlo collision model, comparing for the first time an unpacked (empty) DBD with a packed bed DBD, i.e., a DBD filled with dielectric spheres in the gas gap. The calculations are performed in air, at atmospheric pressure. The discharge is powered by a pulse with a voltage amplitude of −20 kV. When comparing the packed and unpacked DBD reactors with the same dielectric barriers, it is clear that the presence of the dielectric packing leads to a transition in discharge behavior from a combination of negative streamers and unlimited surface streamers on the bottom dielectric surface to a combination of predominant positive streamers and limited surface discharges on the dielectric surfaces of the beads and plates. Furthermore, in the packed bed DBD, the electric field is locally enhanced inside the dielectric material, near the contact points between the beads and the plates, and therefore also in the plasma between the packing beads and between a bead and the dielectric wall, leading to values of $4\times {10}
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos	000360957800003	Publication Date	2015-08-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1367-2630;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.786	Times cited	22	Open Access
	Notes				Approved	Most recent IF: 3.786; 2015 IF: 3.558
	Call Number	c:irua:127650			Serial	3777
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	Author	Voss, A.; Wei, H.Y.; Zhang, Y.; Turner, S.; Ceccone, G.; Reithmaier, J.P.; Stengl, M.; Popov, C.
	Title	Strong attachment of circadian pacemaker neurons on modified ultrananocrystalline diamond surfaces			Type	A1 Journal article
	Year	2016	Publication	Materials science and engineering: part C: biomimetic materials	Abbreviated Journal	Mat Sci Eng C-Mater
	Volume	64	Issue	64	Pages	278-285
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Diamond is a promising material for a number of bio-applications, including the fabrication of platforms for attachment and investigation of neurons and of neuroprostheses, such as retinal implants. In the current work ultrananocrystalline diamond (UNCD) films were deposited by microwave plasma chemical vapor deposition, modified by UV/O-3 treatment or NH3 plasma, and comprehensively characterized with respect to their bulk and surface properties, such as crystallinity, topography, composition and chemical bonding nature. The interactions of insect circadian pacemaker neurons with UNCD surfaces with H-, O- and NH2-terminations were investigated with respect to cell density and viability. The fast and strong attachment achieved without application of adhesion proteins allowed for advantageous modification of dispersion protocols for the preparation of primary cell cultures. Centrifugation steps, which are employed for pelletizing dispersed cells to separate them from dispersing enzymes, easily damage neurons. Now centrifugation can be avoided since dispersed neurons quickly and strongly attach to the UNCD surfaces. Enzyme solutions can be easily washed off without losing many of the dispersed cells. No adverse effects on the cell viability and physiological responses were observed as revealed by calcium imaging. Furthermore, the enhanced attachment of the neurons, especially on the modified UNCD surfaces, was especially advantageous for the immunocytochemical procedures with the cell cultures. The cell losses during washing steps were significantly reduced by one order of magnitude in comparison to controls. In addition, the integration of a titanium grid structure under the UNCD films allowed for individual assignment of physiologically characterized neurons to immunocytochemically stained cells. Thus, employing UNCD surfaces free of foreign proteins improves cell culture protocols and immunocytochemistry with cultured cells. The fast and strong attachment of neurons was attributed to a favorable combination of topography, surface chemistry and wettability. (C) 2016 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lausanne	Editor
	Language		Wos	000376547700033	Publication Date	2016-03-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0928-4931	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.164	Times cited	7	Open Access
	Notes				Approved	Most recent IF: 4.164
	Call Number	UA @ lucian @ c:irua:134164			Serial	4251
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	Author	Wang, Z.; Zhang, Y.; Neyts, E.C.; Cao, X.; Zhang, X.; Jang, B.W.-L.; Liu, C.-jun
	Title	Catalyst preparation with plasmas : how does it work?			Type	A1 Journal article
	Year	2018	Publication	ACS catalysis	Abbreviated Journal	Acs Catal
	Volume	8	Issue	3	Pages	2093-2110
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Catalyst preparation with plasmas is increasingly attracting interest. A plasma is a partially ionized gas, consisting of electrons, ions, molecules, radicals, photons, and excited species, which are all active species for catalyst preparation and treatment. Under the influence of plasma, nucleation and crystal growth in catalyst preparation can be very different from those in the conventional thermal approach. Some thermodynamically unfavorable reactions can easily take place with plasmas. Compounds such as sulfides, nitrides, and phosphides that are produced under harsh conditions can be synthesized by plasma under mild conditions. Plasmas can produce catalysts with smaller particle sizes and controllable structure. Plasma is also a facile tool for reduction, oxidation, doping, etching, coating, alloy formation, surface treatment, and surface cleaning in a simple and direct way. A rapid and convenient plasma template removal has thus been established for zeolite synthesis. It can operate at room temperature and allows the catalyst preparation on temperature-sensitive supporting materials. Plasma is typically effective for the production of various catalysts on metallic substrates. In addition, plasma-prepared transition-metal catalysts show enhanced low-temperature activity with improved stability. This provides a useful model catalyst for further improvement of industrial catalysts. In this review, we aim to summarize the recent advances in catalyst preparation with plasmas. The present understanding of plasma-based catalyst preparation is discussed. The challenges and future development are addressed.
	Address
	Corporate Author				Thesis
	Publisher	Amer chemical soc	Place of Publication	Washington	Editor
	Language		Wos	000426804100055	Publication Date	2018-01-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2155-5435	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	10.614	Times cited	81	Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 10.614
	Call Number	UA @ lucian @ c:irua:150880			Serial	4963
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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	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	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	Liang, Y.-S.; Xue, C.; Zhang, Y.-R.; Wang, Y.-N.
	Title	Investigation of active species in low-pressure capacitively coupled N-2/Ar plasmas			Type	A1 Journal article
	Year	2021	Publication	Physics Of Plasmas	Abbreviated Journal	Phys Plasmas
	Volume	28	Issue	1	Pages	013510
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this paper, a self-consistent fluid model is developed focusing on the plasma parameters in capacitively coupled 20% N 2-80% Ar discharges. Measurements of ion density are performed with the help of a floating double probe, and the emission intensities from Ar(4p) and N 2 ( B ) transitions are detected by an optical emission spectroscopy to estimate their relative densities. The consistency between the numerical and experimental results confirms the reliability of the simulation. Then the plasma characteristics, specifically the reaction mechanisms of active species, are analyzed under various voltages. The increasing voltage leads to a monotonous increase in species density, whereas a less homogeneous radial distribution is observed at a higher voltage. Due to the high concentration of Ar gas, Ar + becomes the main ion, followed by the N 2 +</mml:msubsup> ion. Besides the electron impact ionization of neutrals, the charge transfer processes of Ar +/ N 2 and N 2 +</mml:msubsup>/Ar are found to have an impact on the ionic species. The results indicate that adopting the lower charge transfer reaction rate coefficients weakens the Ar + ion density and yields a higher N 2 +</mml:msubsup> ion density. However, the effect on the species spatial distributions and other species densities is limited. As for the excited-state species, the electron impact excitation of background gases remains overwhelming in the formation of Ar(4p), N 2 ( B ), and N 2 ( a ' ), whereas the <mml:msub> N 2 ( A ) molecules are mainly formed by the decay of <mml:msub> N 2 ( B ). In addition, the dissociation of <mml:msub> N 2 collided by excited-state Ar atoms dominates the N generation, which are mostly depleted to produce N + ions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000629931300002	Publication Date	2021-01-22
	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		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 2.115
	Call Number	UA @ admin @ c:irua:177669			Serial	6767
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	Author	Zhang, Z.; Bourgeois, L.; Zhang, Y.; Rosalie, J.M.; Medhekar, N.
	Title	Advanced imaging and simulations of precipitate interfaces in aluminium alloys and their role in phase transformations			Type	P1 Proceeding
	Year	2020	Publication	MATEC web of conferences T2 – 17th International Conference on Aluminium Alloys (ICAA), October 26-29, 2020	Abbreviated Journal
	Volume		Issue		Pages	09003
	Keywords	P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Precipitation is accompanied by the formation and migration of heterophase interfaces. Using the combined approach of advanced imaging and atomistic simulations, we studied the precipitate-matrix interfaces in various aluminium alloy systems, aiming to resolve their detailed atomic structures and illuminate their role in phase transformations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000652552200053	Publication Date	2020-11-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	326	Series Issue		Edition
	ISSN	2261-236x; 2274-7214	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:179147			Serial	6851
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	Author	Peng, X.; Peng, H.; Zhao, K.; Zhang, Y.; Xia, F.; Lyu, J.; Van Tendeloo, G.; Sun, C.; Wu, J.
	Title	Direct visualization of atomic-scale heterogeneous structure dynamics in MnO₂ nanowires			Type	A1 Journal article
	Year	2021	Publication	Acs Applied Materials & Interfaces	Abbreviated Journal	Acs Appl Mater Inter
	Volume	13	Issue	28	Pages	33644-33651
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Manganese oxides are attracting great interest owing to their rich polymorphism and multiple valent states, which give rise to a wide range of applications in catalysis, capacitors, ion batteries, and so forth. Most of their functionalities are connected to transitions among the various polymorphisms and Mn valences. However, their atomic-scale dynamics is still a great challenge. Herein, we discovered a strong heterogeneity in the crystalline structure and defects, as well as in the Mn valence state. The transitions are studied by in situ transmission electron microscopy (TEM), and they involve a complex ordering of [MnO6] octahedra as the basic building tunnels. MnO2 nanowires synthesized using solution-based hydrothermal methods usually exhibit a large number of multiple polymorphism impurities with different tunnel sizes. Upon heating, MnO2 nanowires undergo a series of stoichiometric polymorphism changes, followed by oxygen release toward an oxygen-deficient spinel and rock-salt phase. The impurity polymorphism exhibits an abnormally high stability with interesting small-large-small tunnel size transition, which is attributed to a preferential stabilizer (K+) concentration, as well as a strong competition of kinetics and thermodynamics. Our results unveil the complicated intergrowth of polymorphism impurities in MnO2, which provide insights into the heterogeneous kinetics, thermodynamics, and transport properties of the tunnel-based building blocks.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000677540900101	Publication Date	2021-07-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1944-8244	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	7.504	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 7.504
	Call Number	UA @ admin @ c:irua:180450			Serial	6861
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	Author	Zhang, Y.; Sahoo, P.K.; Ren, P.; Qin, Y.; Cauwenbergh, R.; Nimmegeers, P.; Gandhi, S.R.; Van Passel, S.; Guidetti, A.; Das, S.
	Title	Transition metal-free approach for the late-stage benzylic C(sp³)-H etherifications and esterifications			Type	A1 Journal article
	Year	2022	Publication	Chemical Communications	Abbreviated Journal	Chem Commun
	Volume	58	Issue	81	Pages	11454-11457
	Keywords	A1 Journal article; Engineering Management (ENM); Organic synthesis (ORSY); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS)
	Abstract	Herein, we report a transition metal-free approach for the regioselective functionalisation of benzylic C(sp3)-H bonds using alcohols and carboxylic acids as the nucleophiles. This approach provides a straightforward route for the synthesis of various benzylic ethers and esters to provide a wide generality of this system. Expediently, twelve pharmaceutically relevant compounds have been synthesized using this strategy.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000857171200001	Publication Date	2022-09-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1359-7345; 1364-548x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.9	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 4.9
	Call Number	UA @ admin @ c:irua:190191			Serial	7372
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	Author	Xiaoyan, S.; Zhang, Y.-R.; Wang, Y.-N.; He, J.-X.
	Title	Fluid simulation of the superimposed dual-frequency source effect in inductively coupled discharges			Type	A1 Journal article
	Year	2021	Publication	Physics Of Plasmas	Abbreviated Journal	Phys Plasmas
	Volume	28	Issue	11	Pages	113504-113510
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Superimposition of dual frequencies (DFs) is one of the methods used for controlling plasma distribution in an inductively coupled plasma (ICP) source. The effects of a superimposed DF on the argon plasma characteristics have been investigated using a two-dimensional self-consistent fluid model. When both currents are fixed at 6A, the plasma density drops with decrease in one of the source frequencies due to less efficient heating and the plasma uniformity improves significantly. Moreover, for ICP operated with superimposed DFs (i.e., 4.52MHz/13.56MHz and 2.26MHz/13.56MHz), the current source exhibits the same period as the low frequency (LF) component, and the plasma density is higher than that obtained at a single frequency (i.e., 4.52 and 2.26MHz) with the same total current of 12A. However, at superimposed current frequencies of 6.78MHz/13.56MHz, the plasma density is lower than that obtained at a single frequency of 6.78MHz due to the weaker negative azimuthal electric field between two positive maxima during one period of 6.78MHz. When the superimposed DF ICP operates at 2.26 and 13.56MHz, the rapid oscillations of the induced electric field become weaker during one period of 2.26MHz as the current ratio of 2.26MHz/13.56MHz rises from 24A/7 A to 30A/1 A, and the plasma density drops with the current ratio due to weakened electron heating. The uniformity of plasma increases due to sufficient diffusion under the low-density condition.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000760326100004	Publication Date	2021-11-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1070-664x	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	2.115	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 2.115
	Call Number	UA @ admin @ c:irua:187245			Serial	7974
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	Author	Ying, J.; Xiao, Y.; Chen, J.; Hu, Z.-Y.; Tian, G.; Van Tendeloo, G.; Zhang, Y.; Symes, M.D.D.; Janiak, C.; Yang, X.-Y.
	Title	Fractal design of hierarchical PtPd with enhanced exposed surface atoms for highly catalytic activity and stability			Type	A1 Journal article
	Year	2023	Publication	Nano letters	Abbreviated Journal
	Volume	23	Issue	16	Pages	7371-7378
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Hierarchicalassembly of arc-like fractal nanostructures not onlyhas its unique self-similarity feature for stability enhancement butalso possesses the structural advantages of highly exposed surface-activesites for activity enhancement, remaining a great challenge for high-performancemetallic nanocatalyst design. Herein, we report a facile strategyto synthesize a novel arc-like hierarchical fractal structure of PtPdbimetallic nanoparticles (h-PtPd) by using pyridinium-type ionic liquidsas the structure-directing agent. Growth mechanisms of the arc-likenanostructured PtPd nanoparticles have been fully studied, and precisecontrol of the particle sizes and pore sizes has been achieved. Dueto the structural features, such as size control by self-similaritygrowth of subunits, structural stability by nanofusion of subunits,and increased numbers of exposed active atoms by the curved homoepitaxialgrowth, h-PtPd displays outstanding electrocatalytic activity towardoxygen reduction reaction and excellent stability during hydrothermaltreatment and catalytic process.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001042181100001	Publication Date	2023-08-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1530-6984	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	10.8	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 10.8; 2023 IF: 12.712
	Call Number	UA @ admin @ c:irua:198408			Serial	8870
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	Author	Freund, R.; Canossa, S.; Cohen, S.M.; Yan, W.; Deng, H.; Guillerm, V.; Eddaoudi, M.; Madden, D.G.; Fairen-Jimenez, D.; Lyu, H.; Macreadie, L.K.; Ji, Z.; Zhang, Y.; Wang, B.; Haase, F.; Wöll, C.; Zaremba, O.; Andreo, J.; Wuttke, S.; Diercks, C.S.
	Title	25 years of Reticular Chemistry			Type	A1 Journal article
	Year	2021	Publication	Angewandte Chemie-International Edition	Abbreviated Journal	Angew Chem Int Edit
	Volume		Issue		Pages	anie.202101644
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	At its core, reticular chemistry has translated the precision and expertise of organic and inorganic synthesis to the solid state. While initial excitement over metal‐organic frameworks (MOFs) and covalent organic frameworks (COFs) was undoubtedly fueled by their unprecedented porosity and surface areas, the most profound scientific innovation of the field has been the elaboration of design strategies for the synthesis of extended crystalline solids through strong directional bonds. In this contribution we highlight the different classes of reticular materials that have been developed, how these frameworks can be functionalized and how complexity can be introduced into their backbones. Finally, we show how the structural control over these materials is being extended from the molecular scale to their crystal morphology and shape on the nanoscale, all the way to their shaping on the bulk scale.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000672037800001	Publication Date	2021-03-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1433-7851	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	11.994	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 11.994
	Call Number	EMAT @ emat @c:irua:177778			Serial	6743
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	Author	Wang, C.; Xin, X.; Shu, M.; Huang, S.; Zhang, Y.; Li, X.
	Title	Scalable synthesis of one-dimensional Na₂Li₂Ti₆O₁₄ nanofibers as ultrahigh rate capability anodes for lithium-ion batteries			Type	A1 Journal article
	Year	2019	Publication	Inorganic Chemistry Frontiers	Abbreviated Journal	Inorg Chem Front
	Volume	6	Issue	3	Pages	646-653
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Carbon anode materials for Li-ion batteries have been operated close to their theoretical rate and cycle limits. Therefore, titanium-based materials have attracted great attention due to their high stability. Here, Na2Li2Ti6O14 nanofibers as anode materials were prepared through a controlled electrospinning method. The Na2Li2Ti6O14 nanofibers presented superior electrochemical performance with high rate capability and long cycle life and can be regarded as a competitive anode candidate for advanced Li-ion batteries. One-dimensional (1D) Na2Li2Ti6O14 nanofibers are able to deliver a capacity of 128.5 mA h g(-1) at 0.5C, and demonstrate superior high-rate charge-discharge capability and cycling stability (the reversible charge capacity is 77.8 mA h g(-1) with a capacity retention of 99.45% at the rate of 10C after 800 cycles). The 1D structure is considered to contribute remarkably to increased rate capability and stability. This simple and scalable method indicates that the Na2Li2Ti6O14 nanofibers have a practical application potential for high performance lithium-ion batteries.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000461092500027	Publication Date	2018-11-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2052-1553	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.036	Times cited	3	Open Access	Not_Open_Access
	Notes	; The authors acknowledge financial support from the National Natural Science Foundation of China (21571110), Natural Science Foundation of Zhejiang Province (LY18B010003), and the Ningbo Key Innovation Team (2014B81005), and sponsorship by the K.C. Wong Magna Fund in Ningbo University. ;			Approved	Most recent IF: 4.036
	Call Number	UA @ admin @ c:irua:158566			Serial	5258
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	Author	Zhang, L.; Zhang, Y.-Y.; Zha, G.-Q.; Milošević, M.V.; Zhou, S.-P.
	Title	Skyrmionic chains and lattices in s plus id superconductors			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	101	Issue	6	Pages	064501
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We report characteristic vortex configurations in s + id superconductors with time-reversal symmetry breaking, exposed to magnetic field. A vortex in the s + id state tends to have an opposite phase winding between s- and d-wave condensates. We find that this peculiar feature together with the competition between s- and d-wave symmetry results in three distinct classes of vortical configurations. When either s or d condensate absolutely dominates, vortices form a conventional lattice. However, when one condensate is relatively dominant, vortices organize in chains that exhibit skyrmionic character, separating the chiral components of the s +/- id order parameter into domains within and outside the chain. Such skyrmionic chains are found stable even at high magnetic field. When s and d condensates have comparable strength, vortices split cores in two chiral components to form full-fledged skyrmions, i.e., coreless topological structures with an integer topological charge, organized in a lattice. We provide characteristic magnetic field distributions of all states, enabling their identification in, e.g., scanning Hall probe and scanning SQUID experiments. These unique vortex states are relevant for high-T-c cuprate and iron-based superconductors, where the relative strength of competing pairing symmetries is expected to be tuned by temperature and/or doping level, and can help distinguish s + is and s + id superconducting phases.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000510745600005	Publication Date	2020-02-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.7	Times cited	7	Open Access
	Notes	; The authors acknowledge useful discussions with Yong-Ping Zhang. This research was supported by the National Natural Science Foundation of China under Grants No. 61571277 and No. 61771298. L.-F.Z. and M.V.M. acknowledge support from Research Foundation-Flanders (FWO-Vlaanderen). ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:166507			Serial	6605
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	Author	Bourgeois, L.; Zhang, Y.; Zhang, Z.; Chen, Y.; Medhekar, N., V
	Title	Transforming solid-state precipitates via excess vacancies			Type	A1 Journal article
	Year	2020	Publication	Nature Communications	Abbreviated Journal	Nat Commun
	Volume	11	Issue	1	Pages	1248
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Many phase transformations associated with solid-state precipitation look structurally simple, yet, inexplicably, take place with great difficulty. A classic case of difficult phase transformations is the nucleation of strengthening precipitates in high-strength lightweight aluminium alloys. Here, using a combination of atomic-scale imaging, simulations and classical nucleation theory calculations, we investigate the nucleation of the strengthening phase theta' onto a template structure in the aluminium-copper alloy system. We show that this transformation can be promoted in samples exhibiting at least one nanoscale dimension, with extremely high nucleation rates for the strengthening phase as well as for an unexpected phase. This template-directed solid-state nucleation pathway is enabled by the large influx of surface vacancies that results from heating a nanoscale solid. Template-directed nucleation is replicated in a bulk alloy as well as under electron irradiation, implying that this difficult transformation can be facilitated under the general condition of sustained excess vacancy concentrations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000549162600025	Publication Date	2020-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2041-1723	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	16.6	Times cited	5	Open Access	OpenAccess
	Notes	; The authors are indebted to Matthew Weyland for his expert advice on aberrationcorrected scanning transmission electron microscopy. L.B. would like to acknowledge initial discussions with B.C. Muddle and J.F. Nie many years ago regarding the possible thermodynamic role of vacancies in solid-state precipitation. The authors acknowledge funding from the Australian Research Council (LE0454166, LE110100223), the Victorian State Government and Monash University for instrumentation, and use of the facilities within the Monash Centre for Electron Microscopy. The authors thank Flame Burgmann, Dougal McCulloch and Edwin Mayes for access to and assistance at the Microscopy and Microanalysis Facility at RMIT University. L.B. and N.M. acknowledge the financial support of the Australian Research Council (DP150100558). Authors also gratefully acknowledge the computational support from MonARCH, MASSIVE and the National Computing Infrastructure and Pawsey Supercomputing Centre. ZZ and YZ are thankful to Monash University for a Monash Graduate Scholarship, a Monash International Postgraduate Research Scholarship. Z.Z. is grateful for a Monash Centre for Electron Microscopy Postgraduate Scholarship. The authors are grateful to Anita Hill for advice. ;			Approved	Most recent IF: 16.6; 2020 IF: 12.124
	Call Number	UA @ admin @ c:irua:170797			Serial	6635
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	Author	van der Burgt, J.S.; Geuchies, J.J.; van der Meer, B.; Vanrompay, H.; Zanaga, D.; Zhang, Y.; Albrecht, W.; Petukhov, A.V.; Filion, L.; Bals, S.; Swart, I.; Vanmaekelbergh, D.
	Title	Cuboidal supraparticles self-assembled from cubic CsPbBr3 perovskite nanocrystals			Type	A1 Journal article
	Year	2018	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	122	Issue	122	Pages	15706-15712
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Colloidal CsPbBr3 nanocrystals (NCs) have emerged as promising candidates for various opto-electronic applications, such as light-emitting diodes, photodetectors, and solar cells. Here, we report on the self-assembly of cubic NCs from an organic suspension into ordered cuboidal supraparticles (SPs) and their structural and optical properties. Upon increasing the NC concentration or by addition of a nonsolvent, the formation of the SPs occurs homogeneously in the suspension, as monitored by in situ X-ray scattering measurements. The three-dimensional structure of the SPs was resolved through high-angle annular dark-field scanning transmission electron microscopy and electron tomography. The NCs are atomically aligned but not connected. We characterize NC vacancies on superlattice positions both in the bulk and on the surface of the SPs. The occurrence of localized atomic-type NC vacancies-instead of delocalized ones-indicates that NC-NC attractions are important in the assembly, as we verify with Monte Carlo simulations. Even when assembled in SPs, the NCs show bright emission, with a red shift of about 30 meV compared to NCs in suspension.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000439003600071	Publication Date	2018-06-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447; 1932-7455	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited	60	Open Access	OpenAccess
	Notes	; The authors thank Dr. Rajeev Dattani and Jacques Gorini from the ID02 beamline of the ESRF for their excellent assistance during the X-ray scattering experiments. We also thank Carlo van Overbeek, P. Tim Prins, and Federico Montanarella for their support during the synchrotron experiments. The authors gratefully acknowledge Prof. Dr. Alfons van Blaaderen for fruitful discussions. D.V. acknowledges funding from NWO-CW TOPPUNT “Superficial superstructures.” J.J.G. acknowledges the joint Debye and ESRF graduate programs for the financial support. H.V. gratefully acknowledges the financial support by the Flemish Fund for Scientific Research (FWO grant 1S32617NN). S.B. acknowledges the financial support from the European Research Council (ERC Starting grant # 335078-COLOURATOMS). Y.Z. acknowledges the financial support from the European Union's Horizon 2020 research and innovation program, under the Marie Sklodowska-Curie grant agreement #665501 through a FWO [PEGASUS]2 Marie Sklodowska-Curie fellowship (12U4917N). W.A. acknowledges the financial support from the European Research Council under the European Unions Seventh Framework Program (FP-2007-2013)/ERC Advanced grant agreement 291667 HierarSACol. ; ecas_Sara			Approved	Most recent IF: 4.536
	Call Number	UA @ lucian @ c:irua:153161UA @ admin @ c:irua:153161			Serial	5087
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