Scanning Tunneling Microscopy I General Principles and Applications to Clean and Absorbate-Covered Surfaces

Since the first edition of "Scanning 'funneling Microscopy I" has been pub­ lished, considerable progress has been made in the application of STM to the various classes of materials treated in this volume, most notably in the field of adsorbates and molecular systems. An update of the most recent develop­ ments will be given in an additional Chapter 9. The editors would like to thank all the contributors who have supplied up­ dating material, and those who have provided us with suggestions for further improvements. We also thank Springer-Verlag for the decision to publish this second edition in paperback, thereby making this book affordable for an even wider circle of readers. Hamburg, July 1994 R. Wiesendanger Preface to the First Edition Since its invention in 1981 by G. Binnig, H. Rohrer and coworkers at the IBM Zurich Research Laboratory, scanning tunneling microscopy (STM) has devel­ oped into an invaluable surface analytical technique allowing the investigation of real-space surface structures at the atomic level. The conceptual simplicity of the STM technique is startling: bringing a sharp needle to within a few Angstroms of the surface of a conducting sample and using the tunneling cur­ rent, which flows on application of a bias voltage, to sense the atomic and elec­ tronic surface structure with atomic resolution! Prior to 1981 considerable scepticism existed as to the practicability of this approach.

1. Introduction (With 5 Figures).- 1.1 Historical Remarks on Electron Tunneling.- 1.2 STM and Related Techniques.- 1.2.1 Local Proximal Probes.- 1.2.2 Modes of Operation.- 1.3 Development of the Field.- 1.4 Prospects for the Future.- References.- 2. The Rise of Local Probe Methods.- 3. STM on Metals (With 19 Figures).- 3.1 Tunneling Tip.- 3.2 Tunneling Spectroscopies.- 3.2.1 Current Versus Gap Distance.- 3.2.2 Electronic Structure by dI/dV.- 3.3 Examples on Metal Surfaces.- 3.3.1 Surface Structures.- 3.3.2 Dynamics.- 3.4 Conclusion.- References.- 4. Adsorbate Covered Metal Surfaces and Reactions on Metal Surfaces (With 22 Figures).- 4.1 Imaging of Adsorbates by STM.- 4.1.1 Representation of Individual Adsorbates.- 4.1.2 Resolution and Corrugation in Closed Adlayers.- 4.1.3 Spectroscopy of Adsorbates.- 4.2 Processes at the Metal-Gas Interface.- 4.2.1 Adsorption, Dissociation, Surface Diffusion.- 4.2.2 Formation of Ordered Adsorbate Layers.- 4.3 Structure Modifications of Metal Surfaces.- 4.3.1 Adsorbate-Induced Reconstructive Transformations.- 4.3.2 Oxidation Reactions.- 4.4 Epitaxial Growth of Metals on Metal Substrates.- 4.5 Conclusions.- References.- 5. STM on Semiconductors (With 29 Figures).- 5.1 Experimental Technique.- 5.1.1 Topographic Imaging.- 5.1.2 Tunneling Spectroscopy.- 5.2 Scanning Tunneling Microscopy/Spectroscopy on Surfaces.- 5.2.1 Clean Group IV Semiconductors.- 5.2.2 Clean Compound Semiconductor Surfaces.- 5.2.3 Adsorbates and Overlayers on Semiconductors.- 5.2.4 Chemical Reactions on Semiconductor Surfaces.- 5.3 Other Tunneling Techniques Applied to Semiconductors.- 5.3.1 Surface Photovoltage.- 5.3.2 Tunneling-Induced Luminescence.- 5.3.3 Potentiometry.- 5.3.4 Ballistic Electron Emission Microscopy (BEEM).- References.- 6. STM on Layered Materials (With 44 Figures).- 6.1 STM Studies of Graphite.- 6.1.1 Site Asymmetry, Energy-Dependent Corrugation, Tunneling Spectroscopy and Electronic Structure of the Graphite Surface.- 6.1.2 Giant Corrugations, Tip-Sample Interaction and Elastic Response of the Graphite Surface.- 6.1.3 Anomalous STM Images.- 6.1.4 STM Imaging of Defects.- 6.1.5 STM Studies of Clusters on the Graphite Surface.- 6.2 STM Studies of Graphite Intercalation Compounds.- 6.2.1 Donor Graphite Intercalation Compounds.- 6.2.2 Acceptor Graphite Intercalation Compounds.- 6.2.3 Interpretation and Comparison with Theoretical Predictions.- 6.3 STM Studies of Transition Metal Dichalcogenides.- 6.4 STM Studies of Charge Density Waves.- 6.4.1 Charge Density Waves in Transition Metal Dichalcogenides.- 6.4.2 Charge Density Wave Defects and Domains.- 6.4.3 Charge Density Waves in Quasi-One-Dimensional Systems.- 6.5 STM Studies of High- Tc Superconductors.- 6.6 Concluding Comments.- References.- 7. Molecular Imaging by STM (With 19 Figures).- 7.1 Introduction to STM of Molecules.- 7.2 STM of Chemisorbed Molecules in Ultrahigh Vacuum.- 7.2.1 Coadsorbed Benzene and CO on Rh(111).- 7.2.2 Copper-Phthalocyanine on Cu(100) and GaAs (110).- 7.2.3 Naphthalene on Pt(111).- 7.3 STM of Alkanes and Their Derivatives.- 7.3.1 Cadmium Arachidate and Other Langmuir-Blodgett Films.- 7.3.2 n-Alkanes on Graphite.- 7.3.3 Alkylbenzenes on Graphite.- 7.4 STM of Liquid Crystals.- 7.4.1 Alkylcyanobiphenyls.- 7.4.2 Other Liquid Crystals.- 7.5 STM of Polymers.- 7.5.1 PODA, PMMA, and PMPS on Graphite.- 7.5.2 Polyethylene on Graphite.- 7.6 Other Molecules.- 7.7 Conclusions.- References.- 8. STM on Superconductors (With 21 Figures).- 8.1 Theory of Tunneling into Superconductors.- 8.1.1 Coulomb Blockade.- 8.2 Low Temperature STM Spectroscopy on Classical Superconductors.- 8.3 Vortices.- 8.4 Organic Superconductors.- 8.5 STM Topography on High-Tc Superconductors.- 8.5.1 Granularity and Growth Structures.- 8.5.2 Potentiometry.- 8.5.3 Incommensurate Modulation.- 8.6 STM Spectroscopy on High-Tc Superconductors.- 8.6.1 Normal State Spectroscopy.- 8.6.2 STM Spectroscopy of the Superconducting State.- 8.6.3 Energy Gap.- 8.7 Concluding Remarks.- References.- 9. Recent Developments (With 13 Figures).- 9.1 STM on Metal Surfaces.- 9.2 Adsorption on Metal Surfaces.- 9.2.1 Dynamics of Surface Processes.- 9.2.2 Adsorbate Structures.- 9.2.3 Adsorbate-Induced Reconstructions.- 9.2.4 Phase Transitions.- 9.2.5 Metal-on-Metal Epitaxy.- 9.3 Molecular Imaging by STM.- 9.3.1 STM of Molecules on Metals in Ultrahigh Vacuum.- 9.3.2 Naphthalene, Azulene and Methylazulenes on Pt(111).- 9.3.3 Benzene on Pt(111).- 9.3.4 Ethylene on Pt(111).- 9.3.5 C60 on Au(111) and Cu(111).- 9.3.6 Conclusions.- 9.4 STM on Superconductors.- 9.4.1 STM on Conventional Superconductors.- 9.4.2 STM on High-Tc Superconductors.- 9.4.3 Scanning Probe Microscopy on High-Tc Superconductors.- References.