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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 Low Energy Electron Diffraction from Si 111 7x7 and Ultrathin Films on Substrate Crystals

Download or read book Low Energy Electron Diffraction from Si 111 7x7 and Ultrathin Films on Substrate Crystals written by Wai-Kong Pan Lai and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Low Energy Electron Diffraction From SI(111)7X7 and Ultrathin Films on Substrate Crystals" by Wai-kong, Pan, Lai, 黎偉江, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. DOI: 10.5353/th_b3122107 Subjects: Low energy electron diffraction Thin films Crystals

Book A Low Energy Electron Diffraction Study of Ge 111

Download or read book A Low Energy Electron Diffraction Study of Ge 111 written by Raymond J. Phaneuf and published by . This book was released on 1985 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 In Situ Microscopy in Materials Research

Download or read book In Situ Microscopy in Materials Research written by Pratibha L. Gai and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: 2. High Temperature UHV-STM System 264 3. Hydrogen Desorption Process on Si (111) Surface 264 4. (7x7) - (1 xl) Phase Transition on Si (111) Surface 271 Step Shifting under dc Electric Fields 275 5. 6. Conclusions 280 Acknowledgements and References 281 12. DYNAMIC OBSERVATION OF VORTICES IN SUPERCONDUCTORS USING ELECTRON WAVES 283 by Akira Tonomura 1. Introduction 283 2. Experimental Method 284 2. 1 Interference Microscopy 284 2. 2 Lorentz Microscopy 287 Observation of Superconducting Vortices 288 3. 3. 1 Superconducting Vortices Observed by Interference Microscopy 288 3. 1. 1 Profile Mode 288 3. 1. 2 Transmission Mode 291 3. 2 Superconducting Vortices Observed by Lorentz Microscopy 293 3. 3 Observation of Vortex Interaction with Pinning Centers 294 3. 3. 1 Surface Steps 295 3. 3. 2 Irradiated Point Defects 296 4. Conclusion 298 References 299 13. TEM STUDIES OF SOME STRUCTURALLY FLEXIBLE SOLIDS AND THEIR ASSOCIATED PHASE TRANSFORMATIONS 301 by Ray L. Withers and John G. Thompson 1. Introduction 301 2. Tetrahedrally Comer-Connected Framework Structures 302 3. Tetragonal a-PbO 311 4. Compositionally Flexible Anion-Deficient Fluorites and the "Defect Fluorite" to C-type Sesquioxide Transition 320 5. Summary and Conclusions 327 Acknowledgements and References 327 Author Index 331 Subject Index 333 List of Contributors A. ASEEV Institute of Semiconductor Physics, Russian Academy of Sciences Novosibirsk, 630090, pr. ac. , Lavrentjeva 13, RUSSIA E. BAUER Department of Physics and Astronomy, Arizona State University Tempe, AZ 85287-1504, U. S. A. G. H.

Book Surface and Interface Characterization by Electron Optical Methods

Download or read book Surface and Interface Characterization by Electron Optical Methods written by Ugo Valdre and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of real space imaging and spatially-resolved spectroscopy in many of the most significant problems of surface and interface behaviour is almost self evident. To join the expertise of the tradi tional surface scientist with that of the electron microscopist has however been a slow and difficult process. In the past few years remarkable progress has been achieved, including the development of new techniques of scanning transmission and reflection imaging as well as low energy microscopy, all carried out in greatly improved vacuum conditions. Most astonishing of all has been the advent of the scanning tunneling electron microscope providing atomic resolution in a manner readily compatible with most surface science diagnostic procedures. The problem of beam damage, though often serious, is increasingly well understood so that we can assess the reliability and usefulness of the results which can now be obtained in catalysis studies and a wide range of surface science applications. These new developments and many others in more established surface techniques are all described in this book, based on lectures given at a NATO Advanced Study Institute held in Erice, Sicily, at Easter 1987. It is regretted that a few lectures on low energy electron diffraction and channeling effects could not be included. Fifteen lecturers from seven different Countries and 67 students from 23 Countries and a wide variety of backgrounds attended the school.

Book RHEED Studies of Vicinal Si 111 Surfaces and Ag Films Grown on Si 111

Download or read book RHEED Studies of Vicinal Si 111 Surfaces and Ag Films Grown on Si 111 written by and published by . This book was released on 1998 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reflection high energy electron diffraction (RHEED) was used to study the growth of silver films and the evolution of step structures on the silicon (111) surface. Silver films were deposited by molecular beam epitaxy onto the Si(111) 7 x 7 surface. Films deposited below room temperature showed RHEED intensity oscillation whose quality improved with decreasing temperature. RHEED oscillations were also improved by the application of an initial burst in the deposition flux. Such improvement and the temperature dependence of the oscillations is attributed to an increase in the island nucleation density. Vicinal silicon samples miscut from the (111) plane by 1.2°, 2.5°, and 4.5° towards the [2{bar 1}{bar 1}] direction were studied. If the samples were cooled slowly through the 1 x 1 to 7 x 7 phase transition a step bunching transformation would occur that produced large (111) terraces. During this transition the diffraction spot splitting would vanish while maintaining a constant splitting width. This suggest that the transition occurs by the growth of a few terraces incorporating the others with the widths of the other terraces remaining fixed until incorporation.

Book Equilibrium Structure and Properties of Surfaces and Interfaces

Download or read book Equilibrium Structure and Properties of Surfaces and Interfaces written by A. Gonis and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is almost self-evident that surface and interface science, coupled with the electronic structure of bulk materials, playa fundamental role in the understanding of materials properties. If one is to have any hope of understanding such properties as catalysis, microelectronic devices and contacts, wear, lubrication, resistance to corrosion, ductility, creep, intragranular fracture, toughness and strength of steels, adhesion of protective oxide scales, and the mechanical properties of ceramics, one must address a rather complex problem involving a number of fundamental parameters: the atomic and electronic structure, the energy and chemistry of surface and interface regions, diffusion along and across interfaces, and the response of an interface to stress. The intense need to gain an understanding of the properties of surfaces and interfaces is amply attested to by the large number of conferences and workshops held on surface and interface science. Because of this need, the fields of surface and interface science have been established in their own right, although their development presently lags behind that of general materials science associated with bulk, translationally invariant systems. There are good reasons to expect this situation to change rather dramatically in the next few years. Existing techniques for investigating surfaces and interfaces have reached maturity and are increasingly being applied to systems of practical relevance. New techniques are still being created, which drastically widen the scope of applicability of surface and interface studies. On the experimental side, new microscopies are bearing fruit.

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 Low Energy Electron Diffraction

Download or read book Low Energy Electron Diffraction written by Michel A. VanHove and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 617 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface crystallography plays the same fundamental role in surface science which bulk crystallography has played so successfully in solid-state physics and chemistry. The atomic-scale structure is one of the most important aspects in the understanding of the behavior of surfaces in such widely diverse fields as heterogeneous catalysis, microelectronics, adhesion, lubrication, cor rosion, coatings, and solid-solid and solid-liquid interfaces. Low-Energy Electron Diffraction or LEED has become the prime tech nique used to determine atomic locations at surfaces. On one hand, LEED has yielded the most numerous and complete structural results to date (almost 200 structures), while on the other, LEED has been regarded as the "technique to beat" by a variety of other surface crystallographic methods, such as photoemission, SEXAFS, ion scattering and atomic diffraction. Although these other approaches have had impressive successes, LEED has remained the most productive technique and has shown the most versatility of application: from adsorbed rare gases, to reconstructed surfaces of sem iconductors and metals, to molecules adsorbed on metals. However, these statements should not be viewed as excessively dogmatic since all surface sensitive techniques retain untapped potentials that will undoubtedly be explored and exploited. Moreover, surface science remains a multi-technique endeavor. In particular, LEED never has been and never will be self sufficient. LEED has evolved considerably and, in fact, has reached a watershed.