“A microstructural study of the thermal stability of atomic layer deposited Al2O3 thin films”. Nistor LC, Richard O, Zhao O, Bender H, Stesmans A, Van Tendeloo G, Institute of physics conference series
T2 –, Microscopy of semiconducting materials , 397 (2003)
Abstract: The thermal stability of amorphous Al2O3 films (similar to8 and 80 nut thick) deposited by atomic layer deposition on HF-last and thin SiO2 covered (001) Si substrates is studied by transmission electron microscopy. The layers are in- and ex-situ annealed in the same temperature range.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
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“Electrochemical growth and characterization of nanostructured ZnO thin films”. Ghica C, Enculescu I, Nistor LC, Matei E, Van Tendeloo G, Journal of optoelectronics and advanced materials 10, 3237 (2008)
Abstract: ZnO is a wide band-gap (ca. 3.4 eV) semiconductor, piezoelectric, pyroelectric, biocompatible, transparent in the visible spectrum and UV light emitting material. The fabrication in 2001 of the first nanobelts of semiconductor oxide materials lead to a rapid expansion of researches concerning one dimensional nanostructures (nanotubes, nanowires, nanobelts), given their possible application in optics, optoelectronics, piezoelectricity, catalysis. Researches carried on up to date evidenced the possibility to obtain an extraordinary variety of ZnO nanostructures, in function of the experimental parameters and the used growth methods. In this work we present morphostructural results on nanostructured ZnO layers obtained by electrochemical deposition. The films have been grown on gold covered glass plates and Si wafers, in various experimental conditions such as: nature of the wetting agents, electrical polarization of the substrate (continuous, pulsed). The influence of the growth conditions on the crystalline structure and morphology of the films is revealed by scanning and transmission electron microscopy studies. The films show a variety of growth morphologies, from entangled-wires-like to honeycomb-like layers. These large-specific-surface layers will be tested as nanostructured substrates for photovoltaic cells with improved efficiency.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.449
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“Revealing nanoscale structural TEM/HRTEM: application on ferroelectric ordering by PMN-PT relaxor ferroelectric”. Ghica C, Nistor L, Van Tendeloo G, Journal of optoelectronics and advanced materials 10, 2328 (2008)
Abstract: Nano-scale ordering may be revealed in transmission electron microscopy (TEM) by at least three techniques that will be presented in this work: selected area electron diffraction, conventional TEM and high-resolution TEM. Digital image processing is used to extract additional information from the high-resolution micrographs. The described methods are illustrated in a microstructural and compositional study of a 90%Pb(Mg1/3Nb2/3)O-3-10%PbTiO2 ceramic sample. High-resolution images reveal the presence of ordered compositional nano-domains, observable in two specific crystallographic orientations. Antiphase boundaries lying in the (111) planes separate them, while (100) and (111) facets separate the ordered domains from the disordered matrix.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.449
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“HREM investigation of a Fe/GaN/Fe tunnel junction”. Nistor L, Bender H, van Landuyt J, Nemeth S, Boeve H, De Boeck J, Borghs G, Institute of physics conference series
T2 –, Royal-Microscopical-Society Conference on Microscopy of Semiconducting, Materials, MAR 25-29, 2001, Univ of Oxford, Oxford, England , 53 (2001)
Abstract: The structure of Fe/GaN/Fe ferromagnetic electrodes is studied by high resolution transmission electron microscopy. The layers grow epitaxially on the GaAs substrate with the top Fe layer 90degrees rotated compared to the bottom one. The interfaces are quite rough. There is an indication of the possible occurrence of Fe3GaAs formation on the GaAs interface.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
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“Atomic imaging of cage like structures of silicon”. Nistor L, Van Tendeloo G, Amelinckx S, Cros C, Physica status solidi: A: applied research 146, 119 (1994). http://doi.org/10.1002/pssa.2211460111
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 12
DOI: 10.1002/pssa.2211460111
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“HRTEM studies of dislocations in cubic BN”. Nistor LC, Van Tendeloo G, Dincã, G, Physica status solidi: A: applied research 201, 2578 (2004). http://doi.org/10.1002/pssa.200405192
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 8
DOI: 10.1002/pssa.200405192
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“Mesoseopic ordering in the 0.9 Pb(Mg1/3Nb2/3)O3-0.1 PbTiO3 relaxor ferroelectric : a HRTEM study”. Nistor LC, Ghica C, Van Tendeloo G, Physica status solidi: C: conferences and critical reviews 4, 736 (2007). http://doi.org/10.1002/pssc.200673753
Abstract: We report a microstructural and compositional study of a 90% Pb(Mg1/3Nb2/3)O-3 – 10% PbTiO3 ceramic sample. High resolution transmission electron microscopy (HRTEM) revealed the presence of compositional ordered nano-domains (1 – 4 mn), observable in two specific orientations, [0 (1) over bar 1] and [1 1 (2) over bar]. However, the visibility and the ordering degree of the nano-domains on the HRTEM images are not at all obvious. Fourier filtering of the images clearly revealed the ordered domains. Antiphase boundaries lying in the (111) planes separate them, while (100) and (111) facets separate the ordered domains from the disordered matrix. Their shape is plate-like, not uniformly spread in the disordered matrix. Their average size varies in different regions of the sample, most probably due to a non-uniform distribution of Ti, as observed by energy dispersive X-ray spectroscopy. (c) 2007 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 2
DOI: 10.1002/pssc.200673753
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“Strain mapping around dislocations in diamond and cBN”. Willems B, Nistor L, Ghica C, Van Tendeloo G, Physica status solidi: A: applied research 202, 2224 (2005). http://doi.org/10.1002/pssa.200561923
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 4
DOI: 10.1002/pssa.200561923
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“Structural aspects of CVD idamond wafers grown at different hydrogen flow rates”. Nistor L, van Landuyt J, Ralchenko V, Physica status solidi: A: applied research 171, 5 (1999). http://doi.org/10.1002/(SICI)1521-396X(199907)174:1<5::AID-PSSA5>3.3.CO;2-3
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 15
DOI: 10.1002/(SICI)1521-396X(199907)174:1<5::AID-PSSA5>3.3.CO;2-3
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“Colloid size distributions in ion implanted glass”. Nistor LC, van Landuyt J, Barton JD, Hole DE, Skelland ND, Townsend PD, Journal of non-crystalline solids 162, 217 (1993). http://doi.org/10.1016/0022-3093(93)91240-4
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.766
Times cited: 63
DOI: 10.1016/0022-3093(93)91240-4
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“Gallium colloid formation during ion implantation of glass”. Hole DE, Townsend PD, Barton JD, Nistor LC, van Landuyt J, Journal of non-crystalline solids 180, 266 (1995). http://doi.org/10.1016/0022-3093(94)00477-3
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.766
Times cited: 34
DOI: 10.1016/0022-3093(94)00477-3
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“Growth and characterization of a-axis textured ZnO thin films”. Nistor LC, Ghica C, Matei D, Dinescu G, Dinescu M, Van Tendeloo G, Journal of crystal growth 277, 26 (2005). http://doi.org/10.1016/j.jcrysgro.2004.12.162
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.751
Times cited: 44
DOI: 10.1016/j.jcrysgro.2004.12.162
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“Microstructural characterization of diamond films deposited on c-BN crystals”. Nistor L, Buschmann V, Ralchenko V, Dinca G, Vlasov I, van Landuyt J, Fuess H, Diamond and related materials
T2 –, 10th European Conference on Diamond, Diamond-Like Materials, Nitrides, and Silicon Carbide (Diamond 1999), SEP 12-17, 1999, PRAGUE, CZECH REPUBLIC 9, 269 (2000). http://doi.org/10.1016/S0925-9635(99)00246-0
Abstract: The morphology and structure of diamond films, deposited on cubic boron nitride (c-BN) crystals by microwave-plasma-enhanced chemical vapor deposition, is studied by high-resolution scanning electron microscopy and micro-Raman spectroscopy. The c-BN crystals, with sizes of 200 to 350 mu m and grown by a high-temperature/high-pressure technique, were embedded in a copper holder, and used as substrates in deposition runs of 15 min to 5 h. The nucleation centers for diamond appear as well-shaped cuboctahedral crystallites, having diameters of approximately 100 nm. With increasing deposition time the diamond crystallites grew larger, forming islands on the c-BN faces. In some cases, epitaxial growth was observed on the (111) c-BN faces where coalesced particles gave rise to very smooth regions. A number of diamond crystals with peculiar shapes are observed, such as a pseudo five-fold symmetry due to multiple twinning. Moreover, both randomly distributed carbon tubes, about 100 nn in diameter and 1 mu m in length, and spherically shaped features are observed in samples prepared under the typical conditions of diamond deposition, this effect being ascribed to the influence of plasma-sputtered copper contamination. Quite unusual diamond crystals with a deep, pyramidal-shaped hole in the middle grew on the copper substrate between the c-BN crystals. (C) 2000 Elsevier Science S.A. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.561
Times cited: 9
DOI: 10.1016/S0925-9635(99)00246-0
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“Nanocrystalline diamond films: transmission electron microscopy and Raman spectroscopy characterization”. Nistor LC, van Landuyt J, Ralchenko VG, Obratzova ED, Smolin AA, Diamond and related materials 6, 159 (1997)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.561
Times cited: 116
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“The influence of the h-BN morphology and structure on the c-BN growth”. Nistor L, Teodorescu V, Ghica C, van Landuyt J, Dinca G, Georgeoni P, Diamond and related materials
T2 –, 11th European Conference on Diamond, Diamond-like Materials, Carbon, Nanotubes, Nitrides and Silicon Carbide (Diamond 2000), SEP 03-08, 2000, OPORTO, PORTUGAL 10, 1352 (2001). http://doi.org/10.1016/S0925-9635(00)00377-0
Abstract: The morphology and structure of hexagonal graphitic BN (h-BN) powders with graphitization indices GI <5, used as precursors for the synthesis of cubic BN (c-BN) crystals, has been investigated by transmission electron microscopy in diffraction contrast and high resolution. We show that besides the GI, which is a general parameter for controlling the structural quality of h-EN ponders, some other microstructural features strongly influence the synthesis of c-BN. In our opinion, the high reactivity of some h-BN powders results from the presence of some nucleation centers for c-BN, observed at the edges of the h-BN particles. They are formed by a rearrangement of the graphitic (0002) planes by bending back, joining in pairs and forming locally nanoarches (half nanotubes). In these particular places, the nature of bonding locally turns towards sp(3), as in the case of c-BN, (C) 2001 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.561
Times cited: 17
DOI: 10.1016/S0925-9635(00)00377-0
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“Formation of diamond nanocrystals in laser-irradiated amorphous carbon films”. Nistor LC, van Landuyt J, Ralchenko VG, Kononenko TV, Obraztsova ED, Strelnitsky VE, International Conference on the New Diamond Science and Technology 4, 25 (1994)
Keywords: P3 Proceeding; Electron microscopy for materials research (EMAT)
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“High resolution electron microscopy and electron spin resonance studies on cubic boron nitride crystals made by high-pressure/high-temperature synthesis”. Nistor L, Nistor SV, Dincã, G, van Landuyt J, Schoemaker D, Copaciu V, Georgeoni P, Arnici N, Diamonds an related materials 8, 738 (1999). http://doi.org/10.1016/S0925-9635(98)00282-9
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.561
Times cited: 7
DOI: 10.1016/S0925-9635(98)00282-9
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“Incorporation and localization of substitutional Mn2+ ions in cubic ZnS quantum dots”. Nistor SV, Stefan M, Nistor LC, Goovaerts E, Van Tendeloo G, Physical review : B : condensed matter and materials physics 81, 035336 (2010). http://doi.org/10.1103/PhysRevB.81.035336
Abstract: Multifrequency electron paramagnetic resonance (EPR) and high resolution transmission electron microscopy (HRTEM) investigations were performed on small (2 nm) cubic ZnS nanocrystals (quantum dotsQDs) doped with 0.2% mol Mn2+, self-assembled into a mesoporous structure. The EPR data analysis shows that the substitutional Mn2+ ions are localized at Zn2+ sites subjected to a local axial lattice distortion, resulting in the observed zero-field-splitting parameter |D|=41×10−4 cm−1. The local distortion is attributed to the presence in the second shell of ligands of a stacking fault or twin, which alters the normal stacking sequence of the cubic structure. The HRTEM results confirm the presence of such extended planar defects in a large percentage of the investigated QDs, which makes possible the proposed substitutional Mn2+ impurity ions localization model. Based on these results it is suggested that the high doping levels of Mn2+ ions observed in cubic ZnS and possible in other II-VI semiconductor QDs prepared at low temperatures can be explained by the assistance of the extended lattice defects in the impurities incorporation.
Keywords: A1 Journal article; Nanostructured and organic optical and electronic materials (NANOrOPT); Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 55
DOI: 10.1103/PhysRevB.81.035336
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“Ordering and defects in BanTaxTiyO3n ternary oxides”. Nistor L, Van Tendeloo G, Amelinckx S, Shpanchenko RV, van Landuyt J, Electron Microscopy 1994, Vols 2a And 2b: Applications In Materials Sciences , 869 (1994)
Keywords: P1 Proceeding; Electron microscopy for materials research (EMAT)
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