| Records |
| 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 |
| Permanent link to this record |
| |
|
| |
| Author |
Wang, Y.; Yu, M.Y.; Chen, Z.Y. |
| Title |
Coherent relativistic wake wave of a charged object moving steadily in a plasma |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
| Volume |
84 |
Issue |
2 |
Pages |
025501,1-025501,5 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
Nonlinear electron plasma waves driven by a finite-charged particle pulse or rigid object moving at relativistic speeds are investigated. Quasi-stationary smooth and spiky wake waves comoving with the object are found. Localized soliton-like solutions are also shown to exist. Relativistic effects tend to prevent their formation because of the electron mass increase. The application of the very-large-amplitude wake density waves as a source of ultrahigh-energy cosmic-ray events is discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Stockholm |
Editor |
|
| Language |
|
Wos |
000294727900017 |
Publication Date |
2011-07-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-8949;1402-4896; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.28 |
Times cited |
5 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.28; 2011 IF: 1.204 |
| Call Number |
UA @ lucian @ c:irua:92435 |
Serial |
381 |
| Permanent link to this record |
| |
|
| |
| Author |
Wang, Y.J.; Nickel, H.A.; McCombe, B.D.; Peeters, F.M.; Hai, G.Q.; Shi, J.M.; Devreese, J.T.; Wu, X.G. |
| Title |
Resonant magnetopolaron effects in GaAs/AlGaAs MQWs at high magnetic fields |
Type |
P3 Proceeding |
| Year |
1997 |
Publication |
|
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
797-800 |
| Keywords |
P3 Proceeding; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
World Scientific |
Place of Publication |
Singapore |
Editor |
|
| Language |
|
Wos |
|
Publication Date |
0000-00-00 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Additional Links |
UA library record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:19305 |
Serial |
2890 |
| Permanent link to this record |
| |
|
| |
| Author |
Canioni, R.; Roch-Marchal, C.; Sécheresse, F.; Horcajada, P.; Serre, C.; Hardi-Dan, M.; Férey, G.; Grenèche, J.-M.; Lefebvre, F.; Chang, J.-S.; Hwang, Y.-K.; Lebedev, O.; Turner, S.; Van Tendeloo, G. |
| Title |
Stable polyoxometalate insertion within the mesoporous metal organic framework MIL-100(Fe) |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
| Volume |
21 |
Issue |
4 |
Pages |
1226-1233 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Successful encapsulation of polyoxometalate (POM) within the framework of a mesoporous iron trimesate MIL-100(Fe) sample has been achieved by direct hydrothermal synthesis in the absence of fluorine. XRPD, 31P MAS NMR, IR, EELS, TEM and 57Fe Mössbauer spectrometry corroborate the insertion of POM within the cavities of the MOF. The experimental Mo/Fe ratio is 0.95, in agreement with the maximum theoretical amount of POM loaded within the pores of MIL-100(Fe), based on steric hindrance considerations. The POM-MIL-100(Fe) sample exhibits a pore volume of 0.373 cm3 g−1 and a BET surface area close to 1000 m2 g−1, indicating that small gas molecules can easily diffuse inside the cavities despite the presence of heavy phosphomolybdates. These latter contribute to the decrease in the overall surface area, due to the increase in molar weight, by 65%. Moreover, the resulting Keggin containing MIL-100(Fe) solid is stable in aqueous solution with no POM leaching even after more than 2 months. In addition, no exchange of the Keggin anions by tetrabutylammonium perchlorate in organic media has been observed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000286110400042 |
Publication Date |
2010-11-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
158 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:88642 |
Serial |
3145 |
| Permanent link to this record |
| |
|
| |
| Author |
Esken, D.; Noei, H.; Wang, Y.; Wiktor, C.; Turner, S.; Van Tendeloo, G.; Fischer, R.A. |
| Title |
ZnO@ZIF-8 : stabilization of quantum confined ZnO nanoparticles by a zinc methylimidazolate framework and their surface structural characterization probed by CO2 adsorption |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
| Volume |
21 |
Issue |
16 |
Pages |
5907-5915 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The microporous and activated zeolitic imidazolate framework (Zn(MeIM)2; MeIM = imidazolate-2-methyl; ZIF-8) was loaded with the MOCVD precursor diethyl zinc [Zn(C2H5)2]. Exposure of ZIF-8 to the vapour of the volatile organometallic molecule resulted in the formation of the inclusion compound [Zn(C2H5)2]0.38@ZIF-8 revealing two precursor molecules per cavity. In a second step the obtained material was treated with oxygen (5 vol% in argon) at various temperatures (oxidative annealing) to achieve the composite material ZnO0.35@ZIF-8. The new material was characterized with powder XRD, FT-IR, UV-vis, solid state NMR, elemental analysis, N2 sorption measurements, and transmission electron microscopy. The data give evidence for the presence of nano-sized ZnO particles stabilized by ZIF-8 showing a blue-shift of the UV-vis absorption caused by quantum size effect (QSE). The surface structure and reactivity of embedded ZnO nanoparticles were characterized via carbon dioxide adsorption at different temperatures monitored by ultra-high vacuum FTIR techniques. It was found that the surface of ZnO nanoparticles is dominated by polar OZnO and ZnZnO facets as well as by defect sites, which all exhibit high reactivity towards CO2 activation forming various adsorbed carbonate and chemisorbed CO2δ− species. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000289260000012 |
Publication Date |
2011-03-19 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
76 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:88641 |
Serial |
3936 |
| Permanent link to this record |
| |
|
| |
| Author |
Wang, Z.; Wang, Y.B.; Yin, J.; Tovari, E.; Yang, Y.; Lin, L.; Holwill, M.; Birkbeck, J.; Perello, D.J.; Xu, S.; Zultak, J.; Gorbachev, R.V.; Kretinin, A.V.; Taniguchi, T.; Watanabe, K.; Morozov, S.V.; Andelkovic, M.; Milovanović, S.P.; Covaci, L.; Peeters, F.M.; Mishchenko, A.; Geim, A.K.; Novoselov, K.S.; Fal'ko, V.I.; Knothe, A.; Woods, C.R. |
| Title |
Composite super-moiré lattices in double-aligned graphene heterostructures = Composite super-moire lattices in double-aligned graphene heterostructures |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Science Advances |
Abbreviated Journal |
|
| Volume |
5 |
Issue |
12 |
Pages |
eaay8897 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| Abstract |
When two-dimensional (2D) atomic crystals are brought into close proximity to form a van der Waals heterostructure, neighbouring crystals may influence each other's properties. Of particular interest is when the two crystals closely match and a moire pattern forms, resulting in modified electronic and excitonic spectra, crystal reconstruction, and more. Thus, moire patterns are a viable tool for controlling the properties of 2D materials. However, the difference in periodicity of the two crystals limits the reconstruction and, thus, is a barrier to the low-energy regime. Here, we present a route to spectrum reconstruction at all energies. By using graphene which is aligned to two hexagonal boron nitride layers, one can make electrons scatter in the differential moire pattern which results in spectral changes at arbitrarily low energies. Further, we demonstrate that the strength of this potential relies crucially on the atomic reconstruction of graphene within the differential moire super cell. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000505069600089 |
Publication Date |
2019-12-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2375-2548 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
71 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:165754 |
Serial |
6289 |
| Permanent link to this record |
| |
|
| |
| Author |
Sun, M.-H.; Zhou, J.; Hu, Z.-Y.; Chen, L.-H.; Li, L.-Y.; Wang, Y.-D.; Xie, Z.-K.; Turner, S.; Van Tendeloo, G.; Hasan, T.; Su, B.-L. |
| Title |
Hierarchical zeolite single-crystal reactor for excellent catalytic efficiency |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Matter |
Abbreviated Journal |
|
| Volume |
3 |
Issue |
4 |
Pages |
1226-1245 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
As a size- and shape-selective catalyst, zeolites are widely used in petroleum and fine-chemicals processing. However, their small micropores severely hinder molecular diffusion and are sensitive to coke formation. Hierarchically porous zeolite single crystals with fully interconnected, ordered, and tunable multimodal porosity at macro-, meso-, and microlength scale, like in leaves, offer the ideal solution. However, their synthesis remains highly challenging. Here, we report a versatile confined zeolite crystallization process to achieve these superior properties. Such zeolite single crystals lead to significantly improved mass transport properties by shortening the diffusion length while maintaining shape-selective properties, endowing them with a high efficiency of zeolite crystals, enhanced catalytic activities and lifetime, highly reduced coke formation, and reduced deactivation rate in bulky-molecule reactions and methanol-to-olefins process. Their industrial utilization can lead to the design of innovative and intensified reactors and processes with highly enhanced efficiency and minimum energy consumption. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000581132600021 |
Publication Date |
2020-08-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:174329 |
Serial |
6727 |
| Permanent link to this record |
