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Book Indium on Silicon 111

    Indium on Silicon 111

    Book Details:
  • Author : Friedrich Klasing
  • Publisher : Cuvillier Verlag
  • Release : 2014-10-01
  • ISBN : 3736948131
  • Pages : 148 pages

Download or read book Indium on Silicon 111 written by Friedrich Klasing and published by Cuvillier Verlag. This book was released on 2014-10-01 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Indium on silicon is a system showing a vast variety of reconstructions depending on preparation and substrate morphology. The (4×1) reconstruction, a self assembled quasi one dimensional chain of indium atoms, can be found among them. It exhibits a reversible phase transition at temperatures of 130 K into a (8 × 2) reconstruction. The nature of the phase transition as well as its driving force have been discussed for more than a decade now. Effects like a Peierls transition, simple lattice distortion and even Jahn-Teller distortions are being considered as the cause of the transition. The question of whether it is of first- or second-order is answered by showing the existence of a robust hysteresis loop of the order parameter, i.e. it is a transition of first-order. The width of the hysteresis of the (4×1)?(8×2) phase-transition is measured by means of high resolution low electron energy diffraction and is determined to be 8.6 K. Furthermore the Si(111)(8×2)-In reconstruction is a system showing a weak correlation between the neighbouring chains which is easily disturbed by adsorbates. The influence of three different adsorbates, namely argon, molecular oxygen and water on the transition characteristics is studied. All of them interact with the surface in a different way. Argon has only a small influence on the transition characteristics and is found to mainly influence the measurement as a diffusive scattering point defect. The expected raise in transition temperature could not be observed. Like argon, the exposure to molecular oxygen seems to reduce the influence of the reconstructions age, i.e. permanent exposure to residual gases, on the transition characteristics. The influence of water adsorption is found to be bigger and contrary to the influence of oxygen and argon. Exposure to small amounts of water heavily disturbs the correlation between rows and growing of (8×2) domains. The reconstruction rapidly ages. Wall et al. excited an extremely undercooled surface state by means of fs-laser excitation as well as to characterize its decay by means of time resolved reflection high electron diffraction. An atomistic model, i.e. a falling row of dominoes, has subsequently been developed. An interesting phenomenon was observed though the rapid ageing of the reconstruction helped explaining it. Necessary expansions of this model are tested by simulating the decay of the high-temperature phase.

Book Surface Microscopy with Low Energy Electrons

Download or read book Surface Microscopy with Low Energy Electrons written by Ernst Bauer and published by Springer. This book was released on 2014-07-10 with total page 513 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book, written by a pioneer in surface physics and thin film research and the inventor of Low Energy Electron Microscopy (LEEM), Spin-Polarized Low Energy Electron Microscopy (SPLEEM) and Spectroscopic Photo Emission and Low Energy Electron Microscopy (SPELEEM), covers these and other techniques for the imaging of surfaces with low energy (slow) electrons. These techniques also include Photoemission Electron Microscopy (PEEM), X-ray Photoemission Electron Microscopy (XPEEM), and their combination with microdiffraction and microspectroscopy, all of which use cathode lenses and slow electrons. Of particular interest are the fundamentals and applications of LEEM, PEEM, and XPEEM because of their widespread use. Numerous illustrations illuminate the fundamental aspects of the electron optics, the experimental setup, and particularly the application results with these instruments. Surface Microscopy with Low Energy Electrons will give the reader a unified picture of the imaging, diffraction, and spectroscopy methods that are possible using low energy electron microscopes.

Book Dissertation Abstracts International

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2001 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Phase Transitions on Clean and Adsorbate Covered Surfaces

Download or read book Phase Transitions on Clean and Adsorbate Covered Surfaces written by W. N. Unertl and published by . This book was released on 1980 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: A summary of the experimental and theoretical results of studies of phase transitions on clean and adsorbate covered surfaces is given. The experimental studies are divided among three categories: (1) Surface Phases of Se Adsorbed on Ni(001); (2) Au(110)(1x2)Order-Disorder Transition; (3) Experimental Methods for Study of Surface Phase Transitions. These are presented in order. interpretation of the experimental results relied heavily upon the theoretical work described in Section 3. Keywords: Surface reconstruction, Low energy electron diffraction, Au(110, Se/Ni(001), N2/Ni(110), O/W(110), Finite size effect, Conformal invariance, Monte Carlo simulations.

Book High Temperature Structure Formation and Surface Diffusion of Silver on Silicon Surfaces

Download or read book High Temperature Structure Formation and Surface Diffusion of Silver on Silicon Surfaces written by Dirk Wall and published by Cuvillier Verlag. This book was released on 2012-11-21 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Kurzbeschreibung Die vorliegende Arbeit beschäftigt sich mit Oberflächendiffusion und Strukturbildung an Oberflächen, speziell im Fall Silber auf Silizium. Unterschiedliche Methoden werden kombiniert um Si(001) und Si(111) Oberflächen als auch dazwischen liegende Orientierungen zu untersuchen. niedrigenergetische Elektronenmikroskopie (LEEM) und photoemissions Elektronenmikroskopie (PEEM) wurden verwendet um die Wachstumsdynamik und den Einfluss von Oberflächendiffusion auf die Strukturbildung an Oberflächen unter Ultrahochvakuum (UHV) Bedingungen zu untersuchen. Es wurden ein- und multi-kristalline Ag Inseln und selbstorganisierte Ag Drähte auf unterschiedlichen Si Oberflächen untersucht. Hierfür wurde Ag bei hohen Temperaturen auf Oberflächen aufgebracht, wobei die meisten Untersuchungen in-situ erfolgten. Die Struktur der Ag Inseln und Drähte und deren Orientierung zum Substrat wurde hauptsächlich mit niederenergetischer Elektronenbeugung an kleinen Bereichen (µ-LEED), hochauflösender niederenergetischer Elektronenbeugung (SPA-LEED) und Rasterelektronenmikroskopie (SEM) untersucht. Für die SEM Untersuchungen wurden die präparierten Proben aus dem UHV entnommen um sie in ein SEM zu transferieren und eine statistisch bessere Aussagekraft zu erreichen. Ag(001) und Ag(111) Inseln wurden bei Temperaturen von bis zu 700°C gewachsen. Mit steigender Wachstumstemperatur verändert sich die überwiegende Form der Inseln von hexagonal zu dreieckig. Die relative Drehung zum Substrat wurde Untersucht und mit einem modifizierten gitter-koinzidenz Modell (CSL) verglichen. Der Vergleich zeigt eine ausgesprochen gute Übereinstimmung der experimentellen Daten mit der Theorie, bei der praktisch alle Drehwinkel erklärt werden. Oberflächendiffusionsfelder wurden beim thermischen Zerfall und während der Desorption von Silberinseln untersucht. Um die Inseln bilden sich ein oder mehrere konzentrische rekonstruktionsbedingte Zonen. Ein einfaches kontinuum Diffusionsmodell zur Erklärung des Zerfallsmechanismus wird vorgestellt. Das Modell beinhaltet ein bereits zuvor präsentiertes Modell als einen Spezialfall und wurde in Zusammenarbeit mit J. Krug und I. Lohmar an der Universität zu Köln entwickelt. Unterschiedlichste Diffusionsparameter können mit diesem Modell bestimmt werden und stimmen sehr gut mit Literaturvergleichswerten überein. Der Zerfall der Inseln auf vizinalen Oberflächen kann nicht mehr mit diesem Modell erklärt werden, da eine Anisotropie auftritt, die die Rotationssymmetrie aufhebt. SPA-LEED Resultate zur Multistufenbildung und Facettierung sowie numerische Simulationen werden hinzugezogen und können mit Hilfe eines in der Literatur bekannten Modells praktisch alle experimentellen Daten erklären und so ein fast all-umfassendes Verständnis der Ursachen der Anisotropie erzeugen. Die Ergebnisse werden auch auf Ergebnisse zu Indium auf vizinalem Silizium angewendet und können auch hier die Überraschende Isotropie erklären. Außer den Inseln bilden sich auf Si(001) auch noch Drähte. Das Wachstum dieser Drähte wurde untersucht um eine Diskussion in der Literatur über die Ursache der Drahtbildung aufzuklären. Einkristalline Drähte wurden auf sehr genau orientiertem Si(001) und auf vizinalen Flächen präpariert. Alle Drähte orientieren sich entlang einer der beiden Hauptsymmetrierichtungen der Oberfläche. Ihr Wachstum ist thermisch aktiviert und erstaunlicherweise unabhängig von der Fehlneigung. Dennoch richten sich die Drähte mit zunehmender Fehlneigung und damit Stufendichte parallel zu den Stufenkanten aus. Die Resultate können jedoch die Diskussion ob Diffusionsanisotropie oder Verspannung die Ursache für das Drahtwachstum sind nicht aufklären, da diese zu stark ineinander überkoppeln. Dennoch kommen wir zu dem Entschluss, dass die Drahtausrichtung durch die zunehmende Diffusionsanisotropie verursacht wird. Description The present work deals with surface diffusion and structure formation, mainly for the case of Silver on Silicon surfaces. Various techniques are combined to investigate flat and vicinal surfaces oriented in the Si(001) and Si(111) directions as well as intermediate orientations. Low energy electron microscopy (LEEM) and photoemission electron microscopy (PEEM) were used to study the growth dynamics and diffusion involved in structure formation in ultrahigh vacuum (UHV) conditions. The investigated structure formation deals with single- and multi-crystalline Ag islands and self-organized Ag wires on various Si surfaces. Ag was deposited at elevated temperatures, while the investigations were mainly carried out in-situ. The structure of the grown Ag islands and wires was investigated with either small area low energy electron diffraction (µ-LEED), spot profile analyzing-low energy electron diffraction (SPA-LEED), or scanning electron microscopy (SEM). The SEM investigations were the only investigations, where the sample was extracted from the UHV and were carried out to improve the statistical significance of the data. Ag(001) and Ag(111) islands were grown at elevated temperatures of up to 700°C. With increasing growth temperature, the shape of the islands transformed from hexagonally shaped to triangular. The relative rotation to the substrate was investigated and compared to a modified coincidence site lattice approach (CSL) which agreed very well with the experimental results. Practically all of the significant rotation angles could be explained by the CSL model. Surface diffusion fields were investigated during the decay of islands in the process of desorption. These islands are surrounded by one or several concentric adsorbate induced reconstruction zones. A simple continuum diffusion model is presented, explaining the decay mechanism. The model contains a previously presented model as a special case and was developed in collaboration with J. Krug and I. Lohmar at the University of Cologne. Several diffusion parameters are extracted from the model and are in excellent agreement with values in literature. The decay of Ag islands on vicinal Si substrates no longer yields concentric circular zones, but the zones become anisotropic, and the model can no longer be applied due to the no lack of rotational symmetry. A model from the literature is used to explain the data in combination with SPA-LEED results on multi-step formation and faceting and numerical simulations. Only a combination of all these techniques is capable of a thorough and all-embracing explanation of surface diffusion. The results are compared to the system of Indium on vicinal Si(001) surfaces. Here, in contrast to Ag on vicinal Si(001), no anisotropy is found and the drawn picture can also explain the surprising diffusion isotropy. Among the islands that were used for the diffusion investigations, on Si(001), wires form. The growth of these single crystalline wires was investigated and an attempt has been taken to clear an ongoing discussion about the cause of the wire formation. The single crystalline wires were grown on flat and vicinal Si(001) surfaces. All wires align to one of the two principal directions of the substrate. Their growth is thermally activated and surprisingly independent of the substrate vicinality. The wires align with the step edges as the sample vicinality and with it the step density is increased. The results cannot lead to a clear decision on which of the discussed phenomena diffusion anisotropy or strain are the cause for self-organized wire formation on vicinal Si(001) surfaces. We can, however, come to the conclusion, that the wire alignment is much more closely linked to the diffusion anisotropy than the formation itself. We therefore state, that the diffusion anisotropy is a possible cause for the wire alignment, restricting the wire growth to one of the possible two directions with increasing diffusion anisotropy.

Book Auger Electron Spectroscopy

    Auger Electron Spectroscopy

    Book Details:
  • Author : Donald T. Hawkins
  • Publisher : Springer Science & Business Media
  • Release : 2012-12-06
  • ISBN : 1468413872
  • Pages : 305 pages

Download or read book Auger Electron Spectroscopy written by Donald T. Hawkins and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: Auger electron spectroscopy is rapidly developing into the single most powerful analytical technique in basic and applied science.for investigating the chemical and structural properties of solids. Its ex plosive growth beginning in 1967 was triggered by the development of Auger analyzers capable of de tecting one atom layer of material in a fraction of a second. Continued growth was guaranteed firstly by the commercial availability of apparatus which combined the capabilities of scanning electron mi croscopy and ion-mill depth profiling with Auger analysis, and secondly by the increasing need to know the atomistics of many processes in fundamental research and engineering applications. The expanding use of Auger analysis was accompanied by an increase in the number of publications dealing with it. Because of the developing nature of Auger spectroscopy, the articles have appeared in many different sources covering diverse disciplines, so that it is extremely difficult to discover just what has or has not been subjected to Auger analysis. In this situation, a comprehensive bibliography is obviou-sly useful to those both inside and outside the field. For those in the field, this bibliography should be a wonderful time saver for locating certain references, in researching a particular topic, or when considering various aspects of instrumentation or data analysis. This bibliography not only provides the most complete listing of references pertinent to surface Auger analysis available today, but it is also a basis for extrapolating from past trends to future expectations.

Book Silicon Molecular Beam Epitaxy

Download or read book Silicon Molecular Beam Epitaxy written by Erwin Kasper and published by Elsevier. This book was released on 2012-12-02 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: This two-volume work covers recent developments in the single crystal growth, by molecular beam epitaxy, of materials compatible with silicon, their physical characterization, and device application. Papers are included on surface physics and related vacuum synthesis techniques such as solid phase epitaxy and ion beam epitaxy.A selection of contents: Volume I. SiGe Superlattices. SiGe strained layer superlattices (G. Abstreiter). Optical properties of strained GeSi superlattices grown on (001)Ge (T.P. Pearsall et al.). Growth and characterization of SiGe atomic layer superlattices (J.-M. Baribeau et al.). Optical properties of perfect and imperfect SiGe superlattices (K.B. Wong et al.). Confined phonons in stained short-period (001) Si/Ge superlattices (W. Bacsa et al.). Calculation of energies and Raman intensities of confined phonons in SiGe strained layer superlattices (J. White et al.). Rippled surface topography observed on silicon molecular beam epitaxial and vapour phase epitaxial layers (A.J. Pidduck et al.). The 698 meV optical band in MBE silicon (N. de Mello et al.). Silicon Growth Doping. Dopant incorporation kinetics and abrupt profiles during silicon molecular beam epitaxy (J.-E. Sundgren et al.). Influence of substrate orientation on surface segregation process in silicon-MBE (K. Nakagawa et al.). Growth and transport properties of SimSb1 (H. Jorke, H. Kibbel). Author Index. Volume. II. In-situ electron microscope studies of lattice mismatch relaxation in GexSi1-x/Si heterostructures (R. Hull et al.). Heterogeneous nucleation sources in molecular beam epitaxy-grown GexSi1-x/Si strained layer superlattices (D.D. Perovic et al.). Silicon Growth. Hydrogen-terminated silicon substrates for low-temperature molecular beam epitaxy (P.J. Grunthaner et al.). Interaction of structure with kinetics in Si(001) homoepitaxy (S. Clarke et al.). Surface step structure of a lens-shaped Si(001) vicinal substrate (K. Sakamoto et al.). Photoluminescence characterization of molecular beam epitaxial silicon (E.C. Lightowlers et al.). Doping. Boron doping using compound source (T. Tatsumi). P-type delta doping in silicon MBE (N.L. Mattey et al.). Modulation-doped superlattices with delta layers in silicon (H.P. Zeindell et al.). Steep doping profiles obtained by low-energy implantation of arsenic in silicon MBE layers (N. Djebbar et al.). Alternative Growth Methods. Limited reaction processing: growth of Si/Si1-xGex for heterojunction bipolar transistor applications (J.L. Hoyt et al.). High gain SiGe heterojunction bipolar transistors grown by rapid thermal chemical vapor deposition (M.L. Green et al.). Epitaxial growth of single-crystalline Si1-xGex on Si(100) by ion beam sputter deposition (F. Meyer et al.). Phosphorus gas doping in gas source silicon-MBE (H. Hirayama, T. Tatsumi). Devices. Narrow band gap base heterojunction bipolar transistors using SiGe alloys (S.S. Iyer et al.). Silicon-based millimeter-wave integrated circuits (J-F. Luy). Performance and processing line integration of a silicon molecular beam epitaxy system (A.A. van Gorkum et al.). Silicides. Reflection high energy electron diffraction study of Cosi2/Si multilayer structures (Q. Ye at al.). Epitaxy of metal silicides (H. von Kanel et al.). Epitaxial growth of ErSi2 on (111)si (D. Loretto et al.). Other Material Systems. Oxygen-doped and nitrogen-doped silicon films prepared by molecular beam epitaxy (M. Tabe et al.). Properties of diamond structure SnGe films grown by molecular beam epitaxy (A. Harwit et al.). Si-MBE: Prospects and Challenges. Prospects and challenges for molecular beam epitaxy in silicon very-large-scale integration (W. Eccleston). Prospects and challenges for SiGe strained-layer epitaxy (T.P. Pearsall). Author Index.

Book Low Energy Electron Diffraction Studies of Transition Metal Oxide Surfaces and Films

Download or read book Low Energy Electron Diffraction Studies of Transition Metal Oxide Surfaces and Films written by Jian Wang and published by . This book was released on 2005 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Dynamics of the Si 111 Surface Phase Transition

Download or read book Dynamics of the Si 111 Surface Phase Transition written by and published by . This book was released on 1999 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors have used low-energy electron microscopy to investigate the dynamics of the Si(111) 7 x 7 --> 1 x 1 phase transition. Because the densities of the two phases differ, the phase transformation is analogous to precipitation in bulk systems: additional material must diffuse to the phase boundaries in order for the transformation to occur. By measuring the size evolution of an ensemble of domains, and comparing the results to simulations, they have identified a new mechanism of precipitate growth. The source of material necessary for the transformation is the random creation of atom/vacancy pairs at the surface. This mechanism contrasts sharply with classical theories of precipitation, in which mass transport kinetics determine the rate of transformation.

Book Electron Microscopy

Download or read book Electron Microscopy written by S. Amelinckx and published by John Wiley & Sons. This book was released on 2008-09-26 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt: Derived from the successful three-volume Handbook of Microscopy, this book provides a broad survey of the physical fundamentals and principles of all modern techniques of electron microscopy. This reference work on the method most often used for the characterization of surfaces offers a competent comparison of the feasibilities of the latest developments in this field of research. Topics include: * Stationary Beam Methods: Transmission Electron Microscopy/ Electron Energy Loss Spectroscopy/ Convergent Electron Beam Diffraction/ Low Energy Electron Microscopy/ Electron Holographic Methods * Scanning Beam Methods: Scanning Transmission Electron Microscopy/ Scanning Auger and XPS Microscopy/ Scanning Microanalysis/ Imaging Secondary Ion Mass Spectrometry * Magnetic Microscopy: Scanning Electron Microscopy with Polarization Analysis/ Spin Polarized Low Energy Electron Microscopy Materials scientists as well as any surface scientist will find this book an invaluable source of information for the principles of electron microscopy.

Book Reflection High Energy Electron Diffraction and Reflection Electron Imaging of Surfaces

Download or read book Reflection High Energy Electron Diffraction and Reflection Electron Imaging of Surfaces written by P.K. Larsen and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the papers presented at the NATO Advanced Research Workshop in "Reflection High Energy Electron Diffraction and Reflection Electron Imaging of Surfaces" held at the Koningshof conference center, Veldhoven, the Netherlands, June 15-19, 1987. The main topics of the workshop, Reflection High Energy Electron Diffraction (RHEED) and Reflection Electron Microscopy (REM), have a common basis in the diffraction processes which high energy electrons undergo when they interact with solid surfaces at grazing angles. However, while REM is a new technique developed on the basis of recent advances in transmission electron microscopy, RHEED is an old method in surface crystallography going back to the discovery of electron diffraction in 1927 by Davisson and Germer. Until the development of ultra high vacuum techniques in the 1960's made instruments using slow electrons more accessable, RHEED was the dominating electron diffraction technique. Since then and until recently the method of Low Energy Electron Diffraction (LEED) largely surpassed RHEED in popularity in surface studies. The two methods are closely related of course, each with its own specific advantages. The grazing angle geometry of RHEED has now become a very useful feature because this makes it ideally suited for combination with the thin growth technique of Molecular Beam Epitaxy (MBE). This combination allows in-situ studies of freshly grown and even growing surfaces, opening up new areas of research of both fundamental and technological importance.

Book Chemical Imaging Analysis

Download or read book Chemical Imaging Analysis written by Freddy Adams and published by Elsevier. This book was released on 2015-06-06 with total page 493 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical Imaging Analysis covers the advancements made over the last 50 years in chemical imaging analysis, including different analytical techniques and the ways they were developed and refined to link the composition and structure of manmade and natural materials at the nano/micro scale to the functional behavior at the macroscopic scale. In a development process that started in the early 1960s, a variety of specialized analytical techniques was developed – or adapted from existing techniques – and these techniques have matured into versatile and powerful tools for visualizing structural and compositional heterogeneity. This text explores that journey, providing a general overview of imaging techniques in diverse fields, including mass spectrometry, optical spectrometry including X-rays, electron microscopy, and beam techniques. - Provides comprehensive coverage of analytical techniques used in chemical imaging analysis - Explores a variety of specialized techniques - Provides a general overview of imaging techniques in diverse fields