The Experts below are selected from a list of 1296 Experts worldwide ranked by ideXlab platform
Hiroshi Tokumoto - One of the best experts on this subject based on the ideXlab platform.
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atomic scale flattening and Hydrogen Termination of the si 001 surface by wet chemical treatment
Journal of Vacuum Science and Technology, 1996Co-Authors: Yukinori Morita, Hiroshi TokumotoAbstract:An ultrahigh vacuum scanning tunneling microscopy has been applied to analyze wet‐chemically prepared Si(001) surfaces in an atomic scale. The surface treated by 2.5% HF is atomically rough and is covered by featureless corrugations resulting from an etching by OH ions in the solution. The surface treated by HF:HCl=1:19 mixed solution without controlling an oxide‐removal direction is also atomically rough, but is characterized by a kinkful morphology, which reflects the crystallographic nature of the Si(001) surface. On the other hand, the surface treated by the same mixed solution but by controlling the oxide‐removal direction is covered by regular monatomic steps and the ordered dihydride phase on the terrace. From these facts, we have confirmed that these factors, the concentration of the OH ions and the way of the oxide‐removal, play roles in the preparation of the atomically flat Si(001) surface.
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Atomic scale flattening and Hydrogen Termination of the Si(001) surface by wet-chemical treatment
Journal of Vacuum Science and Technology, 1996Co-Authors: Yukinori Morita, Hiroshi TokumotoAbstract:An ultrahigh vacuum scanning tunneling microscopy has been applied to analyze wet‐chemically prepared Si(001) surfaces in an atomic scale. The surface treated by 2.5% HF is atomically rough and is covered by featureless corrugations resulting from an etching by OH ions in the solution. The surface treated by HF:HCl=1:19 mixed solution without controlling an oxide‐removal direction is also atomically rough, but is characterized by a kinkful morphology, which reflects the crystallographic nature of the Si(001) surface. On the other hand, the surface treated by the same mixed solution but by controlling the oxide‐removal direction is covered by regular monatomic steps and the ordered dihydride phase on the terrace. From these facts, we have confirmed that these factors, the concentration of the OH ions and the way of the oxide‐removal, play roles in the preparation of the atomically flat Si(001) surface.An ultrahigh vacuum scanning tunneling microscopy has been applied to analyze wet‐chemically prepared Si(001) surfaces in an atomic scale. The surface treated by 2.5% HF is atomically rough and is covered by featureless corrugations resulting from an etching by OH ions in the solution. The surface treated by HF:HCl=1:19 mixed solution without controlling an oxide‐removal direction is also atomically rough, but is characterized by a kinkful morphology, which reflects the crystallographic nature of the Si(001) surface. On the other hand, the surface treated by the same mixed solution but by controlling the oxide‐removal direction is covered by regular monatomic steps and the ordered dihydride phase on the terrace. From these facts, we have confirmed that these factors, the concentration of the OH ions and the way of the oxide‐removal, play roles in the preparation of the atomically flat Si(001) surface.
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ideal Hydrogen Termination of si 001 surface by wet chemical preparation
Applied Physics Letters, 1995Co-Authors: Yukinori Morita, Hiroshi TokumotoAbstract:A nearly ideal Si(001) surface was prepared by a wet‐chemical method with a solution of HF:HCl=1:19 (pH<1). The surface was examined by scanning tunneling microscopy and was found to be covered by the uniform dihydride phase. Its successful preparation was the direct consequence of the following facts: The suppression of the (111) facet formation due to a low concentration of OH ions in the etchant solution and the stabilization of the surfaces structure due to the formation of the ordered steps.
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Ideal Hydrogen Termination of Si(001) surface by wet‐chemical preparation
Applied Physics Letters, 1995Co-Authors: Yukinori Morita, Hiroshi TokumotoAbstract:A nearly ideal Si(001) surface was prepared by a wet‐chemical method with a solution of HF:HCl=1:19 (pH
J. Ristein - One of the best experts on this subject based on the ideXlab platform.
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Electronic and chemical passivation of hexagonal 6H-SiC surfaces by Hydrogen Termination
Applied Physics Letters, 2001Co-Authors: N. Sieber, B. F. Mantel, Th Seyller, J. Ristein, D. R. Batchelor, Lothar Ley, T. Heller, D. SchmeißerAbstract:Hydrogenation of 6H?SiC (0001) and (000) is achieved by high-temperature Hydrogen treatment. Both surfaces show a low-energy electron diffraction pattern representative of unreconstructed surfaces of extremely high crystallographic order. On SiC(0001), Hydrogenation is confirmed by the observation of sharp Si?H stretching modes. The absence of surface band bending for n- and p-type samples is indicative of electronically passivated surfaces with densities of charged surface states in the gap of below 71010 cm?2 for p-type and 1.71012 cm?2 for n- type samples, respectively. Even after two days in air, the surfaces show no sign of surface oxide in x-ray photoelectron spectroscopy
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Hydrogen Termination and electron emission from cvd diamond surfaces a combined secondary electron emission photoelectron emission microscopy photoelectron yield and field emission study
Diamond and Related Materials, 2000Co-Authors: J. Ristein, M Stammler, K Janischowsky, G KleberAbstract:Abstract The effect of Hydrogen Termination on the electron emission properties of CVD diamond surfaces is investigated. Three kinds of electron emission process, namely secondary electron emission (SEM), photoelectron emission, and field emission are compared on Hydrogen free and Hydrogen terminated surfaces. Electron beam stimulated desorption was employed to desorb Hydrogen from the diamond surface and to pattern H-free areas on otherwise H-covered surfaces. The Hydrogen terminated areas give strong electron emission in contrast to the Hydrogen free surfaces for all emission processes studied. In particular, the Hydrogen free patterns are imaged with comparable contrast by SEM and photoelectron emission microscopy (PEEM). This indicates that the Hydrogen Termination on diamond surfaces reduces the energy barrier for electron emission by lowering the electron affinity of diamond surface. This is confirmed by a drastic difference in the onset for field emission between the Hydrogenated and Hydrogen free parts of the same CVD diamond film. It is further demonstrated by yield spectroscopy that the threshold for electron emission below the gap of diamond is lowered by the Hydrogenation process.
G Kleber - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen Termination and electron emission from cvd diamond surfaces a combined secondary electron emission photoelectron emission microscopy photoelectron yield and field emission study
Diamond and Related Materials, 2000Co-Authors: J. Ristein, M Stammler, K Janischowsky, G KleberAbstract:Abstract The effect of Hydrogen Termination on the electron emission properties of CVD diamond surfaces is investigated. Three kinds of electron emission process, namely secondary electron emission (SEM), photoelectron emission, and field emission are compared on Hydrogen free and Hydrogen terminated surfaces. Electron beam stimulated desorption was employed to desorb Hydrogen from the diamond surface and to pattern H-free areas on otherwise H-covered surfaces. The Hydrogen terminated areas give strong electron emission in contrast to the Hydrogen free surfaces for all emission processes studied. In particular, the Hydrogen free patterns are imaged with comparable contrast by SEM and photoelectron emission microscopy (PEEM). This indicates that the Hydrogen Termination on diamond surfaces reduces the energy barrier for electron emission by lowering the electron affinity of diamond surface. This is confirmed by a drastic difference in the onset for field emission between the Hydrogenated and Hydrogen free parts of the same CVD diamond film. It is further demonstrated by yield spectroscopy that the threshold for electron emission below the gap of diamond is lowered by the Hydrogenation process.
Robert A Wolkow - One of the best experts on this subject based on the ideXlab platform.
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chemical methods for the Hydrogen Termination of silicon dangling bonds
Chemical Physics Letters, 2007Co-Authors: Iana Dogel, Stanislav A Dogel, Jason L Pitters, Gino A Dilabio, Robert A WolkowAbstract:Abstract Highly ordered Hydrogen-terminated silicon surfaces are ideal testing grounds for molecular electronics. However, upon formation of these surfaces it is inevitable that some surface sites are not capped by Hydrogen. These remaining dangling bonds can interfere with the chemical and electronic properties of nanostructures formed on the silicon surface. In this work, using scanning tunneling microscopy, high resolution electron energy loss spectroscopy and ab initio computational methods, we explore two chemical approaches to refining the Hydrogen Termination process. We investigate the utility of diimide (N 2 H 2 ) and N , N -diethylhydroxylamine (DEHA) as Hydrogen atom sources that have the ability to cap dangling bonds.
T H Geballe - One of the best experts on this subject based on the ideXlab platform.
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epitaxial yttria stabilized zirconia on Hydrogen terminated si by pulsed laser deposition
Applied Physics Letters, 1990Co-Authors: David K Fork, D B Fenner, G A N Connell, Julia M Phillips, T H GeballeAbstract:Epitaxial yttria‐stabilized zirconia films were grown on Si (100) and Si (111) by pulsed laser deposition. Rutherford backscattering spectroscopy indicates a high degree of crystalline perfection with a channeling minimum yield of 5.3%. A necessary predeposition process is removal of native silicon oxide from the Si prior to film growth. This is done outside the deposition chamber at 23 °C using a wet‐chemical Hydrogen‐Termination procedure. Epitaxial YBa2Cu3O7−δ films have been grown on these films.
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Epitaxial yttria‐stabilized zirconia on Hydrogen‐terminated Si by pulsed laser deposition
Applied Physics Letters, 1990Co-Authors: David K Fork, D B Fenner, G A N Connell, Julia M Phillips, T H GeballeAbstract:Epitaxial yttria‐stabilized zirconia films were grown on Si (100) and Si (111) by pulsed laser deposition. Rutherford backscattering spectroscopy indicates a high degree of crystalline perfection with a channeling minimum yield of 5.3%. A necessary predeposition process is removal of native silicon oxide from the Si prior to film growth. This is done outside the deposition chamber at 23 °C using a wet‐chemical Hydrogen‐Termination procedure. Epitaxial YBa2Cu3O7−δ films have been grown on these films.
