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Suche nach „[IQMA]“ hat 159 Publikationen gefunden
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    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Vortrag

    M. Lanza, M. Porti, M. Nafría, Günther Benstetter, Werner Frammelsberger, Heiko Ranzinger, Edgar Lodermeier, G. Jaschke

    Influence of the manufacturing process on the electrical properties of thin (< 4 nm) Hafnium based high-k stacks observed with CAFM

    18th European Symposium on Reliability of Electronic Devices, Failure Physics and Analysis (ESREF), Arcachon, Frankreich

    2007

    Elektrotechnik und MedientechnikIQMA

    Zeitschriftenartikel

    S. Gsell, M. Schreck, Günther Benstetter, Edgar Lodermeier, B. Stritzker

    Combined AFM-SEM Study of the Diamond Nucleation Layer on Ir(001)

    Diamond and Related Materials, vol. 16, no. 4, pp. 665-670

    2007

    Abstract anzeigen

    During bias enhanced nucleation (BEN) of diamond on iridium the nucleation centres are gathered in discrete islands — the so called “domains”. The topographic signature of these domains has been clarified in the present study by two different concepts. First scanning electron microscopy (SEM) and atomic force microscopy (AFM) were combined to take images with both techniques of a small identical area on a standard BEN sample. In spite of the 2–3 nm deep roughening of the iridium it turned clearly out that the surface shows a 1 nm deep depression within the domains compared with the surface of the surrounding layer. On a second sample which did not show the normal roughening the domains could be identified directly from AFM images. The topographic signature of the domains was the same. Conductive AFM measurements showed that inside and outside the domains the carbon nucleation layer behaves like a high resistivity dielectric sustaining fields up to 107 V/cm. Finally, the temporal development of the domain patterns was studied by consecutive biasing steps on one sample. Depending on the local ion bombardment conditions we observed lateral growth or shrinkage on the same sample. This result suggests that domain formation is a continuous process during the whole BEN procedure starting from a local nucleation event and subsequent lateral expansion.

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Zeitschriftenartikel

    M. Lanza, M. Porti, M. Nafría, Günther Benstetter, Werner Frammelsberger, Heiko Ranzinger, Edgar Lodermeier, G. Jaschke

    Influence of the manufacturing process on the electrical properties of thin (< 4 nm) Hafnium based high-k stacks observed with CAFM

    Microelectronics Reliability, vol. 47, no. 9, pp. 1424-1428

    2007

    Abstract anzeigen

    In this work, the dependence of the electrical characteristics of some thin (<4 nm) HfO2, HfSiO and HfO2/SiO2 stacks on their manufacturing process is studied at the nanoscale. Topography, current maps and current–voltage (I–V) characteristics have been collected by conductive atomic force microscope (CAFM), which show that their conductivity depends on some manufacturing parameters. Increasing the annealing temperature, physical thickness or Hafnium content makes the structure less conductive.

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Vortrag

    Günther Benstetter, Werner Frammelsberger, Edgar Lodermeier, Heiko Ranzinger, D. Liu, Peter Breitschopf, W. Bergbauer, Alexander Hofer

    Raster-Sonden-Mikroskopie (SPM) in der Fehler- und Zuverlässigkeitsanalytik

    VDE Fehlermechanismen bei kleinen Geometrien, Grainau

    2006

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Vortrag

    Günther Benstetter, W. Bergbauer, T. Lutz, Werner Frammelsberger

    Kelvin Probe Force Microscopy – An appropriate tool for the electrical characterisation of LED heterostructures

    17th European Symposium - Reliability of Electron Devices, Failure Physics and Analysis (ESREF) 2006, Wuppertal

    2006

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Vortrag

    Günther Benstetter, Peter Breitschopf, B. Knoll, Werner Frammelsberger

    Intermittent contact scanning capacitance microscopy – An improved method for 2D doping profiling

    Nanotech Northern Europe, Helsinki, Finnland

    2006

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Vortrag

    Günther Benstetter, W. Bergbauer, T. Lutz, Werner Frammelsberger

    Kelvin Probe Force Microscopy – An appropriate tool for the electrical characterisation of LED heterostructures

    Nanotech Northern Europe, Helsinki, Finnland

    2006

    Elektrotechnik und MedientechnikIQMA

    Vortrag

    S. Gsell, M. Schreck, Günther Benstetter, et al.

    Combined AFM-SEM Study of the Diamond Nucleation Layer on Ir(001)

    17th European Conference on Diamond, Diamond-Like Materials, Carbon Nanotubes and Nitrides, Estoril, Portugal

    2006

    Elektrotechnik und MedientechnikIQMA

    Zeitschriftenartikel

    D. Liu, S. Zhang, S.-E. Ong, Günther Benstetter, H. Du

    Surface and electron emission properties of hydrogen-free diamond-like carbon films investigated by atomic force microscopy

    Materials Science & Engineering A, vol. 426, no. 1-2, pp. 114-120

    2006

    Abstract anzeigen

    In this study, we have deposited hydrogen-free diamond-like carbon (DLC) films by using DC magnetron sputtering of graphite target at various r.f. bias voltages. Surface and nanoscale emission properties of these DLC films have been investigated using a combination of atomic force microscopy (AFM)-based nanowear tests and conducting-AFM, by simultaneously measuring the topography and the conductivity of the samples. Nanowear tests show that these DLC films are covered with the thin (1.5–2.0 nm) graphite-like layers at surfaces. Compared to the film bulk structure, the graphite-like surface layers are more conductive. The graphite-like surface layers significantly influence the electron emission properties of these films. Low-energy carbon species can be responsible for the formation of graphite-like surface layers. Nanoscale electron emission measurements have revealed the inhomogeneous emission nature of these films. The low-field emission from these films can be attributed to the existence of sp2-configured nanoclusters inside the films.

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Zeitschriftenartikel

    Werner Frammelsberger, Günther Benstetter, J. Kiely, R. Stamp

    Thickness determination of thin and ultra-thin SiO2 films by C-AFM IV-spectroscopy

    Applied Surface Science, vol. 252, no. 6, pp. 2375-2388

    2006

    Abstract anzeigen

    Conductive atomic force microscopy was used to determine the electrical oxide thickness for five different silicon dioxide layers with thickness in the order of 1.6–5.04 nm. The electrical thickness results were compared with values determined by ellipsometry. A semi-analytical tunnelling current model with one single parameter set was used to superpose current/voltage curves in both the direct tunnelling and the Fowler–Nordheim tunnelling regime regions. The overall electrical oxide thickness was determined by statistical means from results of nearly 3000 IV-curves recorded for different conductive CoCr-coated tips. Good agreement between the shape of model and experimental data was achieved, widely independent of the oxide thickness. Compared with the ellipsometry value, the electrical thickness was larger by a value of 0.36 nm (22%) for the thinnest oxide and smaller by a value of 0.31 nm (6%) for the thickest oxide, while intermediate values yielded differences better than 0.15 nm (<<6%). The physical differences between the measurement techniques were shown to contribute to this observation. In addition, statistical deviations between single and multiple measurements using a single tip and using a number of different tips were analysed. The causes, for example, natural oxide thickness variations, tip wear, air humidity induced effects and contaminations, are evaluated and discussed. The method proposed was able to determine the electrical oxide thickness with a standard deviation in the order of ±±6–9%. The results suggest that for optimal results it is necessary to perform several repetitions of IV-measurements for one sample and, in addition, to employ more than one tip.

    Elektrotechnik und MedientechnikIQMA

    Zeitschriftenartikel

    D. Liu, Y. Liu, J. Li, T. Ma, Günther Benstetter

    Properties and deposition processes of a-C: H films from CH4/Ar dielectric barrier discharge plasmas

    Surface & Coatings Technology, vol. 200, no. 20-21, pp. 5819-5822

    2006

    Abstract anzeigen

    Hydrogenated amorphous carbon (a-C: H) films were deposited from CH4+ Ar gas with low-pressure dielectric barrier discharge (DBD) plasmas. The deposition rate, film hardness and surface roughness were examined as a function of Ar concentration in CH4+ Ar. The experimental results revealed that both film hardness and surface roughness increase with increasing Ar concentration from 20% to 67%, and then decrease for Ar concentration exceeding 67%. Also, the deposition rate decreases monotonously with increasing Ar concentration. The high ratio of Ar+ flux per hydrocarbon species for the cases of Ar concentration exceeding 67% leaded to the decrease in growth rate and in surface roughness. CH4+ and Ar+ kinetic energies during the film deposition process were also analyzed theoretically based on ion drift-diffuse model. The theoretical analysis on ion kinetic energy indicated that the deposition of dense a-C: H film is proportional to an increase in kinetic energy of the hydrocarbon ion and the sputter of energetic Ar+ ions.

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Zeitschriftenartikel

    W. Bergbauer, T. Lutz, Werner Frammelsberger, Günther Benstetter

    Kelvin Probe Force Microscopy – An appropriate tool for the electrical characterisation of LED heterostructures

    Microelectronics Reliability, vol. 46, no. 9-11, pp. 1736-1740

    2006

    Abstract anzeigen

    Light Emitting Diodes (LEDs) are commercially important devices in opto-semiconductor industry. The light emitting properties of LEDs degrade with time of operation and may lead to device failure. Even though the stability and reliability of LEDs are important topics, they are not well researched with AFM to date. This work demonstrates that Kelvin Probe Force Microscopy (KPFM) is an appropriate method to identify specific sites of increased degradation in a semiconductor heterostructure. Furthermore, the study shows that KPFM provides the metrological basis for further investigations with respect to the progress of degradation and its physical background. In this study, KPFM has been used to measure the potential gradient over cross-sectioned LED heterostructure in operation at different states of degradation. The results show significant differences between new and aged LEDs, markedly at specific layers of the LED heterostructure.

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Zeitschriftenartikel

    D. Liu, Günther Benstetter, Werner Frammelsberger

    Nanoscale electron field emissions from the bare, hydrogenated and graphite-like layer covered tetrahedral amorphous carbon films

    Journal of Applied Physics, vol. 99, no. 4

    2006

    DOI: 10.1063/1.2171806

    Abstract anzeigen

    We have compared nanoscale electron field emissions from the bare, hydrogenated, and graphitelike-layer-covered tetrahedral amorphous carbon (ta-C) films. The electron field emission is investigated using a combination of atomic force microscopy (AFM)-based nanowear tests and conducting AFM, by simultaneously measuring the topography and the conductivity of the samples. The analysis of Fowler-Nordheim tunneling currents indicates the formation of filamentlike emission channels within ta-C films. The low-field emission from carbon films is primarily due to a field enhancement arising from conducting nanostructures inside the films. The implications of surface structures for electron field emission are discussed. Electrons are easily delocalized within sp2-bonded rings/chains at a film surface, which leads to an increase in the nanotip emission area. At identical emission currents of 60–80 pA, hydrogenated films are much more easily destroyed due to a relatively insulating surface structure. The results suggest that a very high emission site density, required for field-emission display applications, may be produced by locally modifying a film surface layer.

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Vortrag

    Günther Benstetter, Peter Breitschopf, B. Knoll, Edgar Lodermeier, Alexander Hofer, Werner Frammelsberger

    Intermittent Contact Scanning Capacitance Microscopy-First Results

    Workshop on Scanning Probe Microscopy and Related Techniques, Villach, Österreich

    2005

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Vortrag

    Günther Benstetter, D. Liu, Werner Frammelsberger

    Advanced Atomic Force Microscopy Techniques for Nano-Scale Analysis

    1st Conference of Micro- and Nanotechnology, Wien, Österreich

    2005

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Vortrag

    Peter Breitschopf, Günther Benstetter, B. Knoll, Werner Frammelsberger

    Intermittent contact scanning capacitance microscopy-A novel method for 2D doping profiling

    16th European Symposium on Reliability of Electron Devices, Failure Physics and Analysis (ESREF), Arcachon, Frankreich

    2005

    Elektrotechnik und MedientechnikIQMA

    Zeitschriftenartikel

    Y. Liu, J. Zhang, D. Liu, T. Ma, Günther Benstetter

    A triangular section magnetic solenoid filter for removal of macro- and nano-particles from pulsed graphite cathodic vacuum arc plasmas

    Surface & Coatings Technology, vol. 200, no. 7, pp. 2243-2248

    2005

    DOI: 10.1016/j.surfcoat.2004.09.032

    Abstract anzeigen

    A novel magnetic filter with the triangular section has been designed to remove the macro- and nano-particles from the pulsed cathodic arc plasmas utilized to prepare the tetrahedral amorphous carbon (ta-C) films. The macro- and nano-particles at the surfaces of ta-C films were observed using an optical microscope and an atomic force microscope. The filter was found to be very effective in removing the macro- and nano-particles due to its zigzag-type inner surface structure. Particles that collided with the inner surface of the filter were reflected along the direction opposite to the plasma beam, and therefore separated from the arc plasma. The effect of arc current on the filter efficiency has also been investigated.

    Elektrotechnik und MedientechnikIQMA

    Zeitschriftenartikel

    D. Liu, J. Zhang, Y. Liu, J. Xu, Günther Benstetter

    Growth processes and surface properties of diamondlike carbon films

    Journal of Applied Physics, vol. 97

    2005

    DOI: 10.1063/1.1890446

    Abstract anzeigen

    In this study, we compare the deposition processes and surface properties of tetrahedral amorphous carbon (ta-C) films from filtered pulsed cathodic arc discharge (PCAD) and hydrogenated amorphous carbon (a-C:H) films from electron cyclotron resonance (ECR)-plasma source ion implantation. The ion energy distributions (IEDs) of filtered-PCAD at various filter inductances and Ar gas pressures were measured using an ion energy analyzer. The IEDs of the carbon species in the absence of background gas and at low gas pressures are well fitted by shifted Maxwellian distributions. Film hardness and surface properties show a clear dependence on the IEDs. ta-C films with surface roughness at an atomic level and thin (0.3–0.9 nm) graphitelike layers at the filmsurfaces were deposited at various filter inductances in the highly ionized plasmas with the full width at half maximum ion energy distributions of 9–16 eV. The a-C:H filmsdeposited at higher H/C ratios of reactive gases were covered with hydrogen and sp3 bonded carbon-enriched layers due to the simultaneous interaction of hydrocarbon species and atomic hydrogen. The effects of deposited species and ion energies on filmsurface properties were analyzed. Some carbon species have insufficient energies to break the delocalized π(nC)bonds at the graphitelike filmsurface, and they can govern filmformation via surface diffusion and coalescence of nuclei. Dangling bonds created by atomic hydrogen lead to uniform chemisorption of hydrocarbon species from the ECR plasmas. The deposition processes of ta-C and a-C:H films are discussed on the basis of the experimental results.

    Elektrotechnik und MedientechnikIQMAMaschinenbau und Mechatronik

    Zeitschriftenartikel

    Peter Breitschopf, Günther Benstetter, B. Knoll, Werner Frammelsberger

    Intermittent contact scanning capacitance microscopy-A novel method for 2D doping profiling

    Microelectronics Reliability, vol. 45, pp. 1568-1571

    2005

    Abstract anzeigen

    In the present study an improved method for 2D doping profiling of semiconductor device structures is presented. The method combines the capabilities of scanning capacitance microscopy (SCM) with the advantages of intermittent contact atomic force microscopy (IC-AFM) and is called intermittent contact scanning capacitance microscopy (IC-SCM). Compared with standard SCM, IC-SCM provides mechanically stable measurement conditions because tip wear is nearly eliminated. Furthermore, background signals without local information are suppressed by demodulating the SCM signal at higher harmonics of the tapping tip frequency. Both, reduced tip wear and higher harmonics demodulation yield improved spatial image resolution at less tip degradation compared with standard SCM.

    Elektrotechnik und MedientechnikIQMA

    Zeitschriftenartikel

    D. Liu, Günther Benstetter

    Conducting atomic force microscopy for nanoscale electron emissions from various diamond-like carbon films

    Applied Surface Science, vol. 249, no. 1-4, pp. 315-321

    2005

    DOI: 10.1016/j.apsusc.2004.12.029

    Abstract anzeigen

    Conducting atomic force microscopy (C-AFM) has been used to compare the nanoscale electron emissions from hydrogen-free (a-C), hydrogenated (a-C:H), and tetrahedral (ta-C) diamond-like carbon films. The current measurements are performed on the locations where the low-resistant surface layers are removed. The measurements show the uniform electron emissions from a-C:H and ta-C films. The inhomogeneous electron emission from the a-C film is primarily due to the conducting graphite clusters inside the film. The analysis of Fowler–Nordheim tunnelling currents indicates the formation of filament-like emission channels inside these films. The implications of film structures for electron field emissions are discussed.