The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Tilo Baumbach - One of the best experts on this subject based on the ideXlab platform.
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Composition-dependent structure of polycrystalline magnetron-Sputtered V–Al–C–N hard coatings studied by XRD, XPS, XANES and EXAFS
Journal of Applied Crystallography, 2013Co-Authors: Bärbel Krause, Susan Darma, M. Kaufholz, Stefan Mangold, Stephen Doyle, S. Ulrich, Michael Stüber, Harald Leiste, Tilo BaumbachAbstract:V–Al–C–N hard coatings with high carbon content were deposited by reactive radio-frequency magnetron Sputtering using an experimental combinatorial approach, deposition from a segmented Sputter Target. The composition-dependent coexisting phases within the coating were analysed using the complementary methods of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge spectroscopy (XANES) and extended X-ray absorption fine-structure spectroscopy (EXAFS). For the analysis of the X-ray absorption near-edge spectra, a new approach for evaluation of the pre-edge peak was developed, taking into account the self-absorption effects in thin films. Within the studied composition range, a mixed face-centred cubic (V,Al)(C,N) phase coexisting with a C–C-containing phase was observed. No indication of hexagonal (V,Al)(N,C) was found. The example of V–Al–C–N demonstrates how important a combination of complementary methods is for the detection of coexisting phases in complex multi-element coatings.
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Composition-dependent structure of polycrystalline magnetron-Sputtered V-Al-C-N hard coatings studied by XRD, XPS, XANES and EXAFS.
Journal of applied crystallography, 2013Co-Authors: Bärbel Krause, Susan Darma, M. Kaufholz, Stefan Mangold, Stephen Doyle, S. Ulrich, Michael Stüber, Harald Leiste, Tilo BaumbachAbstract:V-Al-C-N hard coatings with high carbon content were deposited by reactive radio-frequency magnetron Sputtering using an experimental combinatorial approach, deposition from a segmented Sputter Target. The composition-dependent coexisting phases within the coating were analysed using the complementary methods of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge spectroscopy (XANES) and extended X-ray absorption fine-structure spectroscopy (EXAFS). For the analysis of the X-ray absorption near-edge spectra, a new approach for evaluation of the pre-edge peak was developed, taking into account the self-absorption effects in thin films. Within the studied composition range, a mixed face-centred cubic (V,Al)(C,N) phase coexisting with a C-C-containing phase was observed. No indication of hexagonal (V,Al)(N,C) was found. The example of V-Al-C-N demonstrates how important a combination of complementary methods is for the detection of coexisting phases in complex multi-element coatings.
Wolfgang Ensinger - One of the best experts on this subject based on the ideXlab platform.
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protection of cylinders by ion beam Sputter deposition corrosion of carbon coated aluminium tubes
Surface & Coatings Technology, 2002Co-Authors: O Lensch, B Enders, Th Kraus, Ch Sundermann, Wolfgang EnsingerAbstract:In application, cylinders and tubes may chemically fail when they are exposed to aggressive media. As for other objects, coating with a protective film may improve the situation. However, coating the inner walls of hollow objects, such as tubes, by means of physical vapour deposition techniques is not feasible, because the material to be deposited has to enter the tube under very flat angles to the surface normal of the walls, depending on the ratio of the inner diameter to the tube length. This problem can be overcome when the source of the material to be deposited is located inside the tube. This is possible when Sputter deposition is performed with an ion beam. A Sputter Target is located inside the tube; energetic ions are accelerated into this tube and impinge onto the Target. Thus, material is Sputtered from the Target onto the inner walls of the tube. With this technique, aluminium tubes were coated inside with thin, amorphous carbon films. The corrosion performance in an aqueous chloride-containing environment, where aluminium suffers from pitting corrosion, was evaluated by means of electrochemical polarisation measurements. These showed that the films exhibited low microporosity with a good corrosion protection effect when appropriate deposition process parameters were used.
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Inner wall coating of cylinders by plasma immersion ion implantation for corrosion protection
Surface & Coatings Technology, 2000Co-Authors: Wolfgang Ensinger, Kerstin Volz, B EndersAbstract:Hollow workpieces such as cylinders are often required to exhibit better performance in wear and corrosion behaviour than the material the workpiece is made of can offer. The problem can be overcome when a protective coating is deposited onto the inner walls. However, coating inner walls by means of physical vapour deposition techniques is difficult because the material to be deposited has to enter the hollow object under very flat angles to the wall, depending on the ratio of aperture to inner diameter. This problem can be overcome when the source of the material to be deposited is located inside the workpiece. This is possible when Sputter coating with ions is performed. A Sputter Target is located inside the workpiece. Energetic ions extracted from a plasma in which the workpiece is immersed are accelerated towards the workpiece, enter it and impinge onto the Sputter Target. Thus, material is Sputtered onto the inner wall. At the same time, ions impinge onto the growing film and lead to ion beam mixing effects. This technique has been tested with cylinders made of different materials and with different Sputter Target materials. The deposited films are well adhering and dense and may act as protective coatings against corrosion. This is shown for corrosion of iron in acetic acid, pitting corrosion of aluminium in sodium chloride solution, and hydrogen embrittlement of tantalum in hydrochloric acid.
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Ion-beam assisted coating of tube inner walls by plasma immersion ion implantation
Surface & Coatings Technology, 2000Co-Authors: Wolfgang Ensinger, Kerstin VolzAbstract:Tubes are often required to exhibit better performance in corrosion and wear behaviour than the material the tube is made of can offer. The situation can be improved when the tube is coated with a protective film. This is possible when Sputter coating with ions is performed. A Sputter Target is located inside the tube. Energetic ions extracted from a plasma in which the tube is immersed (plasma immersion ion implantation PIII) are accelerated towards the tube, enter it and impinge onto the Target. Thus, material is Sputtered from the Target onto the inner walls of the tube. Tubes made of stainless steel and of tantalum were used. A part of the stainless steel tube was cut away and replaced by a segment of a silicon wafer. A zirconium Sputter Target was inserted into the tube. Ions from a nitrogen plasma were accelerated into the tube. Thus, zirconium oxynitride films were formed. Tantalum tubes with a platinum Sputter Target inside were treated in an argon plasma. The deposited films were analysed by Rutherford backscattering spectrometry. The results show that PIII treatment of tube inner walls is an effective technique for coating inner walls of tubes with protective films.
Bärbel Krause - One of the best experts on this subject based on the ideXlab platform.
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Composition-dependent structure of polycrystalline magnetron-Sputtered V–Al–C–N hard coatings studied by XRD, XPS, XANES and EXAFS
Journal of Applied Crystallography, 2013Co-Authors: Bärbel Krause, Susan Darma, M. Kaufholz, Stefan Mangold, Stephen Doyle, S. Ulrich, Michael Stüber, Harald Leiste, Tilo BaumbachAbstract:V–Al–C–N hard coatings with high carbon content were deposited by reactive radio-frequency magnetron Sputtering using an experimental combinatorial approach, deposition from a segmented Sputter Target. The composition-dependent coexisting phases within the coating were analysed using the complementary methods of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge spectroscopy (XANES) and extended X-ray absorption fine-structure spectroscopy (EXAFS). For the analysis of the X-ray absorption near-edge spectra, a new approach for evaluation of the pre-edge peak was developed, taking into account the self-absorption effects in thin films. Within the studied composition range, a mixed face-centred cubic (V,Al)(C,N) phase coexisting with a C–C-containing phase was observed. No indication of hexagonal (V,Al)(N,C) was found. The example of V–Al–C–N demonstrates how important a combination of complementary methods is for the detection of coexisting phases in complex multi-element coatings.
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Composition-dependent structure of polycrystalline magnetron-Sputtered V-Al-C-N hard coatings studied by XRD, XPS, XANES and EXAFS.
Journal of applied crystallography, 2013Co-Authors: Bärbel Krause, Susan Darma, M. Kaufholz, Stefan Mangold, Stephen Doyle, S. Ulrich, Michael Stüber, Harald Leiste, Tilo BaumbachAbstract:V-Al-C-N hard coatings with high carbon content were deposited by reactive radio-frequency magnetron Sputtering using an experimental combinatorial approach, deposition from a segmented Sputter Target. The composition-dependent coexisting phases within the coating were analysed using the complementary methods of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge spectroscopy (XANES) and extended X-ray absorption fine-structure spectroscopy (EXAFS). For the analysis of the X-ray absorption near-edge spectra, a new approach for evaluation of the pre-edge peak was developed, taking into account the self-absorption effects in thin films. Within the studied composition range, a mixed face-centred cubic (V,Al)(C,N) phase coexisting with a C-C-containing phase was observed. No indication of hexagonal (V,Al)(N,C) was found. The example of V-Al-C-N demonstrates how important a combination of complementary methods is for the detection of coexisting phases in complex multi-element coatings.
Chintalapalle V. Ramana - One of the best experts on this subject based on the ideXlab platform.
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Effect of W-Ti Target composition on the surface chemistry and electronic structure of WO 3 -TiO 2 films made by reactive Sputtering
Applied Surface Science, 2015Co-Authors: M. Vargas, D.m. Lopez, Neil R. Murphy, John T. Grant, Chintalapalle V. RamanaAbstract:Abstract Tungsten–titanium (W–Ti) mixed oxide thin films were fabricated using reactive Sputtering of W–Ti alloy Targets with Ti content ranging from 0 to 30 wt%. The effect of Target composition on film structure, surface/interface chemistry and chemical valence state of the W and Ti cations was investigated in detail. All films were amorphous in nature as confirmed by X-ray diffraction analyses. For growth times of 1 h, the thicknesses of the W–Ti–O films decreased significantly from 150 to 35 nm with increasing Ti content in the Target, confirming that the oxide film growth behavior is dependent on the Sputter-Target composition. The chemistry and composition of the films probed using X-ray photoelectron spectroscopy (XPS) confirms the existence of W and Ti in their highest oxidation states of 6+ and 4+, respectively. Quantification of binding energy shifts for W and Ti core-level transitions confirms the formation of WO 3 –TiO 2 composite oxide films. Depth profiles confirm and validate film uniformity, as well as film thickness differences and variable oxidation behavior of W and Ti in the films.
Peter Zaumseil - One of the best experts on this subject based on the ideXlab platform.
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Impact of Ti Sputter Target Denitridation on the Crystallographic Orientation of Single Ti Layers and Ti/TiN/AlCu Layer Stacks on Different Oxides
Journal of Electronic Materials, 2009Co-Authors: D. Wolansky, Peter ZaumseilAbstract:The impact of Ti Sputter Target denitridation on the crystallographic orientation of single Ti layers and Ti/TiN/Al layer stacks was studied for three different underlayers: tetraethyl orthosilicate (TEOS)-based chemical vapor deposition (CVD) oxide, silane-based high-density plasma (HDP) CVD oxide, and thermal oxide. A clear correlation was found between Ti crystal orientation and Ti Sputter Target conditioning as well as oxide underlayer. The Ti crystal orientation determines the orientation of the Al in the Ti/TiN/Al layer stacks. The most perfect Al(111) orientation in Ti/TiN/Al layer stacks was found for a Ti layer Sputtered on TEOS oxide after a Ti Target denitridation of more than 5 s.
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Impact of Ti Sputter Target Denitridation on the Crystallographic Orientation of Single Ti Layers and Ti/TiN/AlCu Layer Stacks on Different Oxides
Journal of Electronic Materials, 2009Co-Authors: D. Wolansky, Peter ZaumseilAbstract:The impact of Ti Sputter Target denitridation on the crystallographic orientation of single Ti layers and Ti/TiN/Al layer stacks was studied for three different underlayers: tetraethyl orthosilicate (TEOS)-based chemical vapor deposition (CVD) oxide, silane-based high-density plasma (HDP) CVD oxide, and thermal oxide. A clear correlation was found between Ti crystal orientation and Ti Sputter Target conditioning as well as oxide underlayer. The Ti crystal orientation determines the orientation of the Al in the Ti/TiN/Al layer stacks. The most perfect Al(111) orientation in Ti/TiN/Al layer stacks was found for a Ti layer Sputtered on TEOS oxide after a Ti Target denitridation of more than 5 s.