Search

Your search keyword '"Vandervorst, W."' showing total 1,483 results
Start Over Author "Vandervorst, W."
1,483 results on '"Vandervorst, W."'

201. Non-filamentary (VMCO) memory: A two-and three-dimensional study on switching and failure modes

Author

Celano, U., primary, Gastaldi, C., additional, Subhechha, S., additional, Govoreanu, B., additional, Donadio, G., additional, Franquet, A., additional, Ahmad, T., additional, Detavernier, C., additional, Richard, O., additional, Bender, H., additional, Goux, L., additional, Kar, G. S., additional, van der Heide, P., additional, and Vandervorst, W., additional

Published
2017
Full Text
View/download PDF

206. Nanoscale Localization of an Atom Probe Tip through Electric Field Mapping

Author

Op de Beeck, Jonathan, Fleischmann, C., Vandervorst, W., and Paredis, K.

Abstract

This work concerns one of the main challenges in atom probe tomography (APT) of heterogeneous systems, that is, the reliable placement of evaporated atoms in the reconstructed volume with subnanometer precision. The accurate determination of the nanoscale needle specimen shape constitutes an essential requirement to overcome this challenge as it enables one to include the details of the tip shape in the reconstruction algorithms distortions. Recently, scanning probe microscopy (SPM) has been pioneered as a promising approach to capture the topography of the APT specimen in three dimensions. However, reaching the unusual tip-on-tip measurement configuration requires approaching the specimen with the SPM probe in a highly controlled manner to avoid any damage to probe or specimen. Here, we propose a new method to align the SPM probe with an APT tip through a measurement of the electrostatic interaction between both. The method is free of any mechanical interaction between both tips prior to surface imaging and is applicable for all possible probe geometries. Additional insights into the resolution through a simulation of the electrostatic interaction between the SPM probe and a biased APT tip are provided. In prospect, this study opens doors to probe the electric field around an APT tip in three dimensions.

Published
2020
Full Text
View/download PDF

207. Ion-beam induced oxidation of GaAs and AlGaAs.

Author

Alay, J. L., Vandervorst, W., and Bender, H.

Subjects
*GALLIUM arsenide, *OXYGEN, *IRRADIATION, *OXIDATION
Abstract

Focuses on a study which examined the oxidation of GaAs and Al[subx]Ga[1-x]As targets by oxygen irradiation. Background on secondary ion mass spectrometry; Experimental procedures; Results.

Published
1995
Full Text
View/download PDF

209. Oxygen distribution in silicon-on-insulator layers obtained by zone melting recrystallization.

Author

Mertens, P. W., Leclair, J., Maes, H. E., and Vandervorst, W.

Subjects
OXYGEN, SILICON-on-insulator technology, ZONE melting
Abstract

Presents a study that examined oxygen content in zone melting recrystallization silicon-on-insulator layers. Analysis of the secondary-ion-mass spectrometry profile of the samples; Relation between peak oxygen concentration and silicon layer thickness; Evaluation of the oxygen distribution in the substrate of the samples.

Published
1990
Full Text
View/download PDF

212. Effect of boron doping on the wear behavior of the growth and nucleation surfaces of micro- and nanocrystalline diamond films

Author

Buijnsters, J.G. (author), Tsigkourakos, M.C. (author), Hantschel, T. (author), Gomes, F.O.V. (author), Nuytten, T. (author), Favia, P. (author), Bender, H (author), Arstila, K. (author), Celis, JP (author), Vandervorst, W (author), Buijnsters, J.G. (author), Tsigkourakos, M.C. (author), Hantschel, T. (author), Gomes, F.O.V. (author), Nuytten, T. (author), Favia, P. (author), Bender, H (author), Arstila, K. (author), Celis, JP (author), and Vandervorst, W (author)

Abstract

B-doped diamond has become the ultimate material for applications in the field of microelectromechanical systems (MEMS), which require both highly wear resistant and electrically conductive diamond films and microstructures. Despite the extensive research of the tribological properties of undoped diamond, to date there is very limited knowledge of the wear properties of highly B-doped diamond. Therefore, in this work a comprehensive investigation of the wear behavior of highly B-doped diamond is presented. Reciprocating sliding tests are performed on micro- and nanocrystalline diamond (MCD, NCD) films with varying B-doping levels and thicknesses. We demonstrate a linear dependency of the wear rate of the different diamond films with the B-doping level. Specifically, the wear rate increases by a factor of 3 between NCD films with 0.6 and 2.8 at. % B-doping levels. This increase in the wear rate can be linked to a 50% decrease in both hardness and elastic modulus of the highly B-doped NCD films, as determined by nanoindentation measurements. Moreover, we show that fine-grained diamond films are more prone to wear. Particularly, NCD films with a 3× smaller grain size but similar B-doping levels exhibit a double wear rate, indicating the crucial role of the grain size on the diamond film wear behavior. On the other hand, MCD films are the most wear-resistant films due to their larger grains and lower B-doping levels. We propose a graphical scheme of the wear behavior which involves planarization and mechanochemically driven amorphization of the surface to describe the wear mechanism of B-doped diamond films. Finally, the wear behavior of the nucleation surface of NCD films is investigated for the first time. In particular, the nucleation surface is shown to be susceptible to higher wear compared to the growth surface due to its higher grain boundary line density., Accepted Author Manuscript, Micro and Nano Engineering

Published
2016
Full Text
View/download PDF

213. SIMS Depth Profiling of Si in GaAs

Author

Shepherd, F. R., Vandervorst, W., Lau, W. M., Robinson, W. H., SpringThorpe, A. J., Goldanskii, Vitalii I., editor, Gomer, Robert, editor, Schäfer, Fritz Peter, editor, Toennies, J. Peter, editor, Benninghoven, Alfred, editor, Colton, Richard J., editor, Simons, David S., editor, and Werner, Helmut W., editor

Published
1986
Full Text
View/download PDF

216. Thermal stability and relaxation mechanisms in compressively strained Ge0.94Sn0.06 thin films grown by molecular beam epitaxy

Author

Fleischmann, C., primary, Lieten, R. R., additional, Hermann, P., additional, Hönicke, P., additional, Beckhoff, B., additional, Seidel, F., additional, Richard, O., additional, Bender, H., additional, Shimura, Y., additional, Zaima, S., additional, Uchida, N., additional, Temst, K., additional, Vandervorst, W., additional, and Vantomme, A., additional

Published
2016
Full Text
View/download PDF

219. Retention, disturb and variability improvements enabled by local chemical-potential tuning and controlled Hour-Glass filament shape in a novel W\WO3\Al2O3\Cu CBRAM

Author

Goux, L., primary, Belmonte, A., additional, Celano, U., additional, Woo, J., additional, Folkersma, S., additional, Chen, C. Y., additional, Redolfi, A., additional, Fantini, A., additional, Degraeve, R., additional, Clima, S., additional, Vandervorst, W., additional, and Jurczak, M., additional

Published
2016
Full Text
View/download PDF

221. (Invited) III-V Selective Area Growth and Epitaxial Functional Oxides on Si: From Electronic to Photonic Devices

Author

Merckling, C., primary, Liu, Z., additional, Hsu, M., additional, Hasan, S., additional, Jiang, S., additional, El Kazzi, S., additional, Boccardi, G., additional, Waldron, N., additional, Wang, Z., additional, Tian, B., additional, Pantouvaki, M., additional, Van Campenhout, J., additional, Collaert, N., additional, Heyns, M., additional, Van Thourhout, D., additional, Vandervorst, W., additional, and Thean, A., additional

Published
2016
Full Text
View/download PDF

227. On the nucleation of PdSi and NiSi 2 during the ternary Ni(Pd)/Si(100) reaction

Author

Schrauwen, A, Demeulemeester, J, Kumar, A, Vandervorst, W, Comrie, C M, Detavernier, C, Temst, K, Vantomme, A, Department of Physics, and Faculty of Science

Subjects
SILICIDE FORMATION, PHASE-TRANSFORMATION, Chemistry, NI, BILAYERS, THIN-FILMS, THERMAL-STABILITY, MIXING ENTROPY, DIFFUSION, (111)SI
Abstract

During the solid phase reaction of a Ni(Pd) alloy with Si(100), phase separation of binary Ni- and Pd-silicides occurs. The PdSi monosilicide nucleates at temperatures significantly below the widely accepted nucleation temperature of the binary system. The decrease in nucleation temperature originates from the presence of the isomorphous NiSi, lowering the interface energy for PdSi nucleation. Despite the mutual solubility of NiSi and PdSi, the two binaries coexist in a temperature window of 100 °C. Only above 700 °C a Ni 1– x Pd x Si solid solution is formed, which in turn postpones the NiSi2 formation to a higher temperature due to entropy of mixing. Our findings highlight the overall importance of the interface energy for nucleation in ternary systems.

Published
2013
Full Text
View/download PDF

228. Compositional depth profiling of TaCN thin films

Author

Adelmann, C., Conard, T., Franquet, A., Brijs, B., Munnik, F., Burgess, S., Witters, T., Meersschaut, J., Kittl, J. A., and Vandervorst, W.

Subjects
ERDA, composition profile, AES, EDX, XPS, TaCN, TaC, TaN, ToF-SIMS
Abstract

The composition profiling of thin TaCN films was studied. For the composition profile determination using x-ray photoemission spectrometry (XPS) in combination with Ar sputtering, preferential sputtering effects of N with respect to Ta and C were found to lead to inaccurate elemental concentrations. Sputter yield calculations for the given experimental conditions allowed for the correction of a part of the error, leading to fair accuracy by reference-free measurements. Further improvement of the accuracy was demonstrated by the calibration of the XPS compositions against elastic recoil detection analysis (ERDA) results. For Auger electron spectrometry (AES) in combination with Ar sputtering, accurate results required the calibration against ERDA. Both XPS and AES allowed for a reliable and accurate determination of the compositional profiles of TaCN-based thin films after calibration. Time-of-flight secondary-ion mass spectrometry was also used to assess the composition of the TaCN films. However, the analysis was hampered by large matrix effects due to small unintentional oxygen contents in the films. Energy-dispersive x-ray spectrometry is also discussed, and it is shown that an accurate reference-free measurement of the average film concentration can be achieved.

Published
2012

229. Scanning Spreading Resistance Microscopy as a Technique for Silicon Solar Cell Emitter Structure Characterization

Author

Doering, S., Jakschik, S., Mikolajick, T., Eyben, P., Hantschel, T., and Vandervorst, W.

Subjects
Advanced Photovoltaics : New Concepts and Ultra-High Efficiency, Fundamental Studies
Abstract

26th European Photovoltaic Solar Energy Conference and Exhibition; 122-125, In our work we demonstrate the ability of SSRM (Scanning Spreading Resistance Microscopy) as a technique that visualizes two dimensional dopant distribution maps with high lateral resolution and a high dynamic range. The method is applied to a completely processed multi crystalline silicon solar cell sample exhibiting high ohmic emitter areas between the front metallization grid and a low ohmic emitter underneath the front metal grid. After measuring the device under test, a known calibration sample was scanned to correlate SSRM amplifier output values to actual dopant distribution information. Expected differences in dopant concentration and depth of the emitter are examined.

Published
2011
Full Text
View/download PDF

230. Studying Local Aluminum Back Surface Fields (Al-BSF) Contacts through Scanning Spreading Resistance Microscopy (SSRM)

Author

Uruena, A., John, J., Eyben, P., Vanhaeren, D., Werner, T., Hantschel, T., Vandervorst, W., Poortmans, J., and Mertens, R.

Subjects
Wafer-based Silicon Solar Cells and Materials Technology, Silicon Solar Cell Characterisation and Modelling
Abstract

26th European Photovoltaic Solar Energy Conference and Exhibition; 1530-1533, The purpose of this work is to study rear-side contact schemes in terms of metallization and Back Surface Field (BSF) characterization of industrial-type Passivated Emitter and Rear Cells (PERC local Al-BSF). The approach used to characterize these highly doped regions is the Scanning Spreading Resistance Microscopy technique (SSRM). The SSRM technique gives the carrier distribution information with high spatial resolution. By using this technique, it was possible to obtain the exact resistance profiles of the BSF layers, and from that, quantify the doping level for the local Al BSF. Due to this high spatial resolution, a gradient in the doping level within the BSF has been possible to be detected, showing the effect of the cooling down process. Two different Al thicknesses have been applied to evaluate its impact on the BSF. It has been found that the thicker the Al layer applied for the local BSF case, the thicker the BSF was formed, as it occurs for Al screen printed full BSF case, although the thermodynamic behaviour and the contact area are different.

Published
2011
Full Text
View/download PDF

231. Novel junction design for NMOS Si Bulk-FinFETs with extension doping by PEALD phosphorus doped silicate glass

Author

Sasaki, Y., primary, Ritzenthaler, R., additional, Kimura, Y., additional, De Roest, D., additional, Shi, X., additional, De Keersgieter, A., additional, Kim, M. S., additional, Chew, S. A., additional, Kubicek, S., additional, Schram, T., additional, Kikuchi, Y., additional, Demuynck, S., additional, Veloso, A., additional, Vandervorst, W., additional, Horiguchi, N., additional, Mocuta, D., additional, Mocuta, A., additional, and Thean, A. V-Y., additional

Published
2015
Full Text
View/download PDF

232. Field Effect and Strongly Localized Carriers in the Metal-Insulator Transition MaterialVO2

Author

Martens, K., primary, Jeong, J. W., additional, Aetukuri, N., additional, Rettner, C., additional, Shukla, N., additional, Freeman, E., additional, Esfahani, D. N., additional, Peeters, F. M., additional, Topuria, T., additional, Rice, P. M., additional, Volodin, A., additional, Douhard, B., additional, Vandervorst, W., additional, Samant, M. G., additional, Datta, S., additional, and Parkin, S. S. P., additional

Published
2015
Full Text
View/download PDF

241. A comparison of arsenic and phosphorus extension by Room Temperature and hot ion implantation for NMOS Si bulk-FinFET at N7 (7nm) technology relevant fin dimensions

Author

Sasaki, Y., primary, Ritzenthaler, R., additional, De Keersgieter, A., additional, Chiarella, T., additional, Kubicek, S., additional, Rosseel, E., additional, Waite, A., additional, del Agua Borniquel, J., additional, Colombeau, B., additional, Chew, S. A., additional, Kim, M. S., additional, Schram, T., additional, Demuynck, S., additional, Vandervorst, W., additional, Horiguchi, N., additional, Mocuta, D., additional, Mocuta, A., additional, and Thean, A. V-Y., additional

Published
2015
Full Text
View/download PDF

246. Fundamental aspects of Arn+SIMS profiling of common organic semiconductors

Author

UCL - SST/IMCN/BSMA - Bio and soft matter, Fleischmann, C., Conard, T., Havelund, R., Franquet, A., Poleunis, Claude, Voroshazi, E., Delcorte, Arnaud, Vandervorst, W., UCL - SST/IMCN/BSMA - Bio and soft matter, Fleischmann, C., Conard, T., Havelund, R., Franquet, A., Poleunis, Claude, Voroshazi, E., Delcorte, Arnaud, and Vandervorst, W.

Abstract

We investigate the capabilities and limitations of performing (quantitative) in-depth composition analysis of polymer:fullerene blends, using time-of-flight SIMS with large Arn+ clusters. These blends constitute an important class of organic solar cell materials, whose performance and reliability critically depend on the blend’s physicochemical properties at the nanoscale. We investigate the effect of Ar cluster size n, kinetic energy E and E/n on the secondary ion and sputter yields and evaluate the Ar beam-induced damage in these layers. On the basis of this, the ideal experimental conditions are derived that allow us to investigate matrix effects and variations in sputter yields as function of polymer:fullerene compositions. We demonstrate that time-of-flight SIMS is capable to retrieve quantitative in-depth information in common polythiophene, polycarbazole,and fullerene blends.

Published
2014

247. G-SIMS analysis of organic solar cell materials

Author

UCL - SST/IMCN/BSMA - Bio and soft matter, Franquet, A., Fleischmann, C., Conard, T., Voroshazi, E., Poleunis, Claude, Havelund, R., Delcorte, Arnaud, Vandervorst, W., UCL - SST/IMCN/BSMA - Bio and soft matter, Franquet, A., Fleischmann, C., Conard, T., Voroshazi, E., Poleunis, Claude, Havelund, R., Delcorte, Arnaud, and Vandervorst, W.

Abstract

Interpretation of time-of-flight (TOF)-SIMS spectra of organic molecules could be difficult because of the presence of a high number of secondary ion peaks; this often requires the use of data analysis methods to simplify the TOF-SIMS measurements. In this study, we will demonstrate that the gentle-SIMS method could be applied to more easily interpret the TOF-SIMS spectra of organic solar cell materials. Various conditions of the primary ion beam were used to generate the gentle-SIMS spectra from pure layers of two materials, i.e. PC70BM and PCDTBT. It will be shown that by using specific conditions of the primary ion column, the corresponding molecular ion or characteristic peaks of the pure organic materials are highlighted. Results obtained on an organic layer prepared from a mixture of both materials will be also discussed.

Published
2014

248. Advanced Phosphorus Emitters for High Efficiency Si Solar Cells

Author

Janssens, T., Posthuma, N.E., Van Kerschaver, E., Baert, K., Choulat, P., Everaert, J.L., Goosens, J., Vandervorst, W., and Poortmans, J.

Subjects
Mono- and Multicrystalline Silicon Materials and Cells, Wafer-based Silicon Solar Cells and Materials Technology
Abstract

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 1843-1846, To improve the front passivation phosphorus emitters for high efficiency Si solar cells require a low surface concentration and high sheet resistance. The fabrication of such emitters is studied with a process based on plasma doping or POCl3 diffusion. The improved passivation of POCl3 based emitters results in an increase in Voc. Plasma doping is shown to be a valuable candidate to simplify and better control the advanced emitter formation.

Published
2009
Full Text
View/download PDF

249. Physical characterization of ALD AI2O3 films deposited on GaAs substrates

Author

Franquet, A., Conard, T., Vandervorst, W., Sioncke, S., Caymax, M., Delabie, A., Heyns, M.M., Meuris, M., Brammertz, G., Hemmen, van, J.L., Keuning, W., Kessels, W.M.M., De Gryse, R., Depla, D., Poelman, D., Mathieu, S., Leroy, W.P., Poelman, H., Plasma & Materials Processing, and Atomic scale processing

Abstract

No abstract

Published
2008

Catalog

Books, media, physical & digital resources
See catalog results