The Experts below are selected from a list of 24 Experts worldwide ranked by ideXlab platform
Urs Ramsperger - One of the best experts on this subject based on the ideXlab platform.
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Detecting the topographic, chemical, and magnetic contrast at surfaces with nm spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, Danilo Pescia, Alessandro Vindigni, Urs RamspergerAbstract:Scanning tunnelling microscopy overshadowed other microscopy techniques owing to its unprecedented spatial resolution. However, the lack of secondary electrons in the experiment always motivated the quest for a complementary technique. The Topografiner technology - a precursor of the STM - could not meet this task so far. Nevertheless, it still plays an important role in the arsenal of probing techniques. In this report, we present secondary-electron distributions of low-energy primary electrons directed at a cleaved GaAs(110) surface and preliminary measurements of single-energy surface imaging in a hybrid experiment.
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Improving the Topografiner technology down to nanometer spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, L. G. De Pietro, H. Cabrera, Danilo Pescia, Aram Kostanyan, Alessandro Vindigni, Urs RamspergerAbstract:In Scanning Tunnelling Microscopy (STM) the electrons are confined within the tunneling region, and this limitation has redirected scientists to alternative microscopy techniques, aimed at extracting the electrons away from the tunneling region. The Topografiner - strictly speaking a precursor of STM, originally developed at the National Bureau of Standards - is an example. In this paper we report on the latest improvements of the Topografiner technology that allow resolving topographic contrast with a lateral resolution down to 7 A.
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Simple Finite Element Model of the Topografiner
2014Co-Authors: H. Cabrera, Urs Ramsperger, Alessandro Vindigni, Danilo PesciaAbstract:We have measured the voltage vs distance characteristics at constant current of a tunnel junction consisting of an electron emitting sharp tip placed at a variable distance from a planar anode. At sufficiently large distances, i.e. in the regime of electric field assisted quantum tunneling, the characteristics for different currents follow approximately a power law, the exponent λ being independent of the current. Here we compare and discuss the origin of the observed power law and the measured value of it in terms of electrosta tic properties of the tip-plane junction, taking the geometry of the tip as a hyperboloid of revolution.
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The Topografiner with energy analysis
2013 26th International Vacuum Nanoelectronics Conference (IVNC), 2013Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, A. Redmann, Andreas Fognini, Thomas Michlmayr, Yves Acremann, Danilo Pescia, Urs RamspergerAbstract:The Topografiner technology, developed originally at the National Bureau of Standards (now National Institute of Standards and Technology) with the aim of measuring the surface micro-topography, is less widespread than scanning tunneling microscopy but has a remarkable property: the electrons can escape the tip-surface junction. We have recently used Topografiner imaging to map the surface of various metals and semiconductors with (almost) nanometer lateral spatial resolution. In this paper, we describe our attempt to endowing the NIST Topografiner with an energy analysis of the electrons escaping the junction, with the aim of performing spectroscopy with nanometer spatial resolution.
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Proceedings of 2013 COMSOL Conference in Rotterdam
2013Co-Authors: H. Cabrera, Urs Ramsperger, Alessandro Vindigni, Danilo Andra Zanin, Lorenzo G. De Pietro, Danilo PesciaAbstract:A sharp tip approached perpendicular to a conducting surface at subnanometer distances and biased with a small voltage builds a junction across which electrons can be transferred from the tip apex to the nearest surface atom by direct quantum mechanical tunneling. Such a junction is used e.g. in Scanning Tunneling Microscopy (STM). When the distance d between tip and collector is increased beyond some nanometers, the junction enters the electric field assisted regime, the one underlying the Topografiner technology –an imaging technique widely used in micro- and nano-electronics. Recent experiments in this regime suggest a scaling law which can be tested numerically by verifying the collapsing of a family of electric potential curves, computed at different d, onto one single curve.
Danilo Pescia - One of the best experts on this subject based on the ideXlab platform.
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Detecting the topographic, chemical, and magnetic contrast at surfaces with nm spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, Danilo Pescia, Alessandro Vindigni, Urs RamspergerAbstract:Scanning tunnelling microscopy overshadowed other microscopy techniques owing to its unprecedented spatial resolution. However, the lack of secondary electrons in the experiment always motivated the quest for a complementary technique. The Topografiner technology - a precursor of the STM - could not meet this task so far. Nevertheless, it still plays an important role in the arsenal of probing techniques. In this report, we present secondary-electron distributions of low-energy primary electrons directed at a cleaved GaAs(110) surface and preliminary measurements of single-energy surface imaging in a hybrid experiment.
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Improving the Topografiner technology down to nanometer spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, L. G. De Pietro, H. Cabrera, Danilo Pescia, Aram Kostanyan, Alessandro Vindigni, Urs RamspergerAbstract:In Scanning Tunnelling Microscopy (STM) the electrons are confined within the tunneling region, and this limitation has redirected scientists to alternative microscopy techniques, aimed at extracting the electrons away from the tunneling region. The Topografiner - strictly speaking a precursor of STM, originally developed at the National Bureau of Standards - is an example. In this paper we report on the latest improvements of the Topografiner technology that allow resolving topographic contrast with a lateral resolution down to 7 A.
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Simple Finite Element Model of the Topografiner
2014Co-Authors: H. Cabrera, Urs Ramsperger, Alessandro Vindigni, Danilo PesciaAbstract:We have measured the voltage vs distance characteristics at constant current of a tunnel junction consisting of an electron emitting sharp tip placed at a variable distance from a planar anode. At sufficiently large distances, i.e. in the regime of electric field assisted quantum tunneling, the characteristics for different currents follow approximately a power law, the exponent λ being independent of the current. Here we compare and discuss the origin of the observed power law and the measured value of it in terms of electrosta tic properties of the tip-plane junction, taking the geometry of the tip as a hyperboloid of revolution.
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The Topografiner with energy analysis
2013 26th International Vacuum Nanoelectronics Conference (IVNC), 2013Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, A. Redmann, Andreas Fognini, Thomas Michlmayr, Yves Acremann, Danilo Pescia, Urs RamspergerAbstract:The Topografiner technology, developed originally at the National Bureau of Standards (now National Institute of Standards and Technology) with the aim of measuring the surface micro-topography, is less widespread than scanning tunneling microscopy but has a remarkable property: the electrons can escape the tip-surface junction. We have recently used Topografiner imaging to map the surface of various metals and semiconductors with (almost) nanometer lateral spatial resolution. In this paper, we describe our attempt to endowing the NIST Topografiner with an energy analysis of the electrons escaping the junction, with the aim of performing spectroscopy with nanometer spatial resolution.
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Proceedings of 2013 COMSOL Conference in Rotterdam
2013Co-Authors: H. Cabrera, Urs Ramsperger, Alessandro Vindigni, Danilo Andra Zanin, Lorenzo G. De Pietro, Danilo PesciaAbstract:A sharp tip approached perpendicular to a conducting surface at subnanometer distances and biased with a small voltage builds a junction across which electrons can be transferred from the tip apex to the nearest surface atom by direct quantum mechanical tunneling. Such a junction is used e.g. in Scanning Tunneling Microscopy (STM). When the distance d between tip and collector is increased beyond some nanometers, the junction enters the electric field assisted regime, the one underlying the Topografiner technology –an imaging technique widely used in micro- and nano-electronics. Recent experiments in this regime suggest a scaling law which can be tested numerically by verifying the collapsing of a family of electric potential curves, computed at different d, onto one single curve.
H. Cabrera - One of the best experts on this subject based on the ideXlab platform.
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Detecting the topographic, chemical, and magnetic contrast at surfaces with nm spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, Danilo Pescia, Alessandro Vindigni, Urs RamspergerAbstract:Scanning tunnelling microscopy overshadowed other microscopy techniques owing to its unprecedented spatial resolution. However, the lack of secondary electrons in the experiment always motivated the quest for a complementary technique. The Topografiner technology - a precursor of the STM - could not meet this task so far. Nevertheless, it still plays an important role in the arsenal of probing techniques. In this report, we present secondary-electron distributions of low-energy primary electrons directed at a cleaved GaAs(110) surface and preliminary measurements of single-energy surface imaging in a hybrid experiment.
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Improving the Topografiner technology down to nanometer spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, L. G. De Pietro, H. Cabrera, Danilo Pescia, Aram Kostanyan, Alessandro Vindigni, Urs RamspergerAbstract:In Scanning Tunnelling Microscopy (STM) the electrons are confined within the tunneling region, and this limitation has redirected scientists to alternative microscopy techniques, aimed at extracting the electrons away from the tunneling region. The Topografiner - strictly speaking a precursor of STM, originally developed at the National Bureau of Standards - is an example. In this paper we report on the latest improvements of the Topografiner technology that allow resolving topographic contrast with a lateral resolution down to 7 A.
-
Simple Finite Element Model of the Topografiner
2014Co-Authors: H. Cabrera, Urs Ramsperger, Alessandro Vindigni, Danilo PesciaAbstract:We have measured the voltage vs distance characteristics at constant current of a tunnel junction consisting of an electron emitting sharp tip placed at a variable distance from a planar anode. At sufficiently large distances, i.e. in the regime of electric field assisted quantum tunneling, the characteristics for different currents follow approximately a power law, the exponent λ being independent of the current. Here we compare and discuss the origin of the observed power law and the measured value of it in terms of electrosta tic properties of the tip-plane junction, taking the geometry of the tip as a hyperboloid of revolution.
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The Topografiner with energy analysis
2013 26th International Vacuum Nanoelectronics Conference (IVNC), 2013Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, A. Redmann, Andreas Fognini, Thomas Michlmayr, Yves Acremann, Danilo Pescia, Urs RamspergerAbstract:The Topografiner technology, developed originally at the National Bureau of Standards (now National Institute of Standards and Technology) with the aim of measuring the surface micro-topography, is less widespread than scanning tunneling microscopy but has a remarkable property: the electrons can escape the tip-surface junction. We have recently used Topografiner imaging to map the surface of various metals and semiconductors with (almost) nanometer lateral spatial resolution. In this paper, we describe our attempt to endowing the NIST Topografiner with an energy analysis of the electrons escaping the junction, with the aim of performing spectroscopy with nanometer spatial resolution.
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Proceedings of 2013 COMSOL Conference in Rotterdam
2013Co-Authors: H. Cabrera, Urs Ramsperger, Alessandro Vindigni, Danilo Andra Zanin, Lorenzo G. De Pietro, Danilo PesciaAbstract:A sharp tip approached perpendicular to a conducting surface at subnanometer distances and biased with a small voltage builds a junction across which electrons can be transferred from the tip apex to the nearest surface atom by direct quantum mechanical tunneling. Such a junction is used e.g. in Scanning Tunneling Microscopy (STM). When the distance d between tip and collector is increased beyond some nanometers, the junction enters the electric field assisted regime, the one underlying the Topografiner technology –an imaging technique widely used in micro- and nano-electronics. Recent experiments in this regime suggest a scaling law which can be tested numerically by verifying the collapsing of a family of electric potential curves, computed at different d, onto one single curve.
D. A. Zanin - One of the best experts on this subject based on the ideXlab platform.
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Detecting the topographic, chemical, and magnetic contrast at surfaces with nm spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, Danilo Pescia, Alessandro Vindigni, Urs RamspergerAbstract:Scanning tunnelling microscopy overshadowed other microscopy techniques owing to its unprecedented spatial resolution. However, the lack of secondary electrons in the experiment always motivated the quest for a complementary technique. The Topografiner technology - a precursor of the STM - could not meet this task so far. Nevertheless, it still plays an important role in the arsenal of probing techniques. In this report, we present secondary-electron distributions of low-energy primary electrons directed at a cleaved GaAs(110) surface and preliminary measurements of single-energy surface imaging in a hybrid experiment.
-
Improving the Topografiner technology down to nanometer spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, L. G. De Pietro, H. Cabrera, Danilo Pescia, Aram Kostanyan, Alessandro Vindigni, Urs RamspergerAbstract:In Scanning Tunnelling Microscopy (STM) the electrons are confined within the tunneling region, and this limitation has redirected scientists to alternative microscopy techniques, aimed at extracting the electrons away from the tunneling region. The Topografiner - strictly speaking a precursor of STM, originally developed at the National Bureau of Standards - is an example. In this paper we report on the latest improvements of the Topografiner technology that allow resolving topographic contrast with a lateral resolution down to 7 A.
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The Topografiner with energy analysis
2013 26th International Vacuum Nanoelectronics Conference (IVNC), 2013Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, A. Redmann, Andreas Fognini, Thomas Michlmayr, Yves Acremann, Danilo Pescia, Urs RamspergerAbstract:The Topografiner technology, developed originally at the National Bureau of Standards (now National Institute of Standards and Technology) with the aim of measuring the surface micro-topography, is less widespread than scanning tunneling microscopy but has a remarkable property: the electrons can escape the tip-surface junction. We have recently used Topografiner imaging to map the surface of various metals and semiconductors with (almost) nanometer lateral spatial resolution. In this paper, we describe our attempt to endowing the NIST Topografiner with an energy analysis of the electrons escaping the junction, with the aim of performing spectroscopy with nanometer spatial resolution.
L. G. De Pietro - One of the best experts on this subject based on the ideXlab platform.
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Detecting the topographic, chemical, and magnetic contrast at surfaces with nm spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, Danilo Pescia, Alessandro Vindigni, Urs RamspergerAbstract:Scanning tunnelling microscopy overshadowed other microscopy techniques owing to its unprecedented spatial resolution. However, the lack of secondary electrons in the experiment always motivated the quest for a complementary technique. The Topografiner technology - a precursor of the STM - could not meet this task so far. Nevertheless, it still plays an important role in the arsenal of probing techniques. In this report, we present secondary-electron distributions of low-energy primary electrons directed at a cleaved GaAs(110) surface and preliminary measurements of single-energy surface imaging in a hybrid experiment.
-
Improving the Topografiner technology down to nanometer spatial resolution
2014 27th International Vacuum Nanoelectronics Conference (IVNC), 2014Co-Authors: D. A. Zanin, L. G. De Pietro, H. Cabrera, Danilo Pescia, Aram Kostanyan, Alessandro Vindigni, Urs RamspergerAbstract:In Scanning Tunnelling Microscopy (STM) the electrons are confined within the tunneling region, and this limitation has redirected scientists to alternative microscopy techniques, aimed at extracting the electrons away from the tunneling region. The Topografiner - strictly speaking a precursor of STM, originally developed at the National Bureau of Standards - is an example. In this paper we report on the latest improvements of the Topografiner technology that allow resolving topographic contrast with a lateral resolution down to 7 A.
-
The Topografiner with energy analysis
2013 26th International Vacuum Nanoelectronics Conference (IVNC), 2013Co-Authors: D. A. Zanin, Mehmet Erbudak, L. G. De Pietro, H. Cabrera, A. Redmann, Andreas Fognini, Thomas Michlmayr, Yves Acremann, Danilo Pescia, Urs RamspergerAbstract:The Topografiner technology, developed originally at the National Bureau of Standards (now National Institute of Standards and Technology) with the aim of measuring the surface micro-topography, is less widespread than scanning tunneling microscopy but has a remarkable property: the electrons can escape the tip-surface junction. We have recently used Topografiner imaging to map the surface of various metals and semiconductors with (almost) nanometer lateral spatial resolution. In this paper, we describe our attempt to endowing the NIST Topografiner with an energy analysis of the electrons escaping the junction, with the aim of performing spectroscopy with nanometer spatial resolution.