Fundamentals of Nanoscale Film Analysis

Transcription

1 Fundamentals of Nanoscale Film Analysis Terry L. Alford Arizona State University Tempe, AZ, USA Leonard C. Feldman Vanderbilt University Nashville, TN, USA James W. Mayer Arizona State University Tempe, AZ, USA Springer

2 Contents Preface xiii 1. AnOverview: Concepts, Units, and the Bohr Atom Introduction Nomenclature Energies, Units, andparticles Particle-Wave Duality and Lattice Spacing The Bohr Model 9 Problems Atomic Collisions and Backscattering Spectrometry Introduction Kinematics of Elastic Collisions Rutherford Backscattering Spectrometry Scattering Cross Section and Impact Parameter CentralForce Scattering Scattering Cross Section: Two-Body Deviations from Rutherford Scattering at Low and High Energy Low-Energy Ion Scattering Forward Recoil Spectrometry Center of Mass to Laboratory Transformation 28 Problems Energy Loss of Light Ions and Backscattering Depth Profiles Introduction General Picture of Energy Loss and Units of Energy Loss Energy Loss of MeV Light Ions in Solids Energy Loss in Compounds Bragg's Rule The Energy Width in Backscattering The Shape of the Backscattering Spectrum Depth Profiles with Rutherford Scattering Depth Resolution and Energy-Loss Straggling 47

3 viii Contents 3.9 Hydrogen and Deuterium Depth Profiles Ranges of Hand He Ions Sputtering and Limits to Sensitivity Summary of Scattering Relations 55 Problems Sputter Depth Profiles and Secondary Ion Mass Spectroscopy Introduction Sputtering by Ion Bombardment General Concepts Nuclear Energy Loss Sputtering Yield Secondary Ion Mass Spectroscopy (SIMS) Secondary Neutral Mass Spectroscopy (SNMS) Preferential Sputtering and Depth Profiles Interface Broadening and Ion Mixing Thomas-Fermi Statistical Model of the Atom 80 Problems Ion Channeling Introduction Channeling in Single Crystals Lattice Location of Impurities in Cry stals Channeling Flux Distributions Surface Interaction via a Two-Atom Model The Surface Peak Substrate Shadowing: Epitaxial Au on Ag( 111) Epitaxial Growth Thin Film Analysis 101 Problems Electron-Electron Interactions and the Depth Sensitivity of Electron Spectroscopies Introduction Electron Spectroscopies: Energy Analysis Escape Depth and Detected Volume Inelastic Electron-Electron Collisions Electron Impact Ionization Cross Section Plasmons The Electron Mean Free Path Influence of Thin Film Morphology on Electron Attenuation Range of Electrons in Solids Electron Energy Loss Spectroscopy (EELS) Bremsstrahlung 124 Problems 126

4 Contents ix 7. X-ray Diffraction Introduction Bragg's Law in Real Space Coefficient of Thermal Expansion Measurements Texture Measurements in Polycrystalline Thin Films Strain Measurements in Epitaxial Layers Crystalline Structure Allowed Reflections and Relative Intensities 143 Problems Electron Diffraction Introduction Reciprocal Space Laue Equations Bragg's Law Ewald Sphere Synthesis The Electron Microscope Indexing Diffraction Patterns 166 Problems Photon Absorption in Solids and EXAFS Introduction The Schrödinger Equation Wave Functions Quantum Numbers, Electron Configuration, and Notation Transition Probability Photoelectric Effect Square-Well Approximation Photoelectric Transition Probability for a Hydrogenic Atom X-ray Absorption Extended X-ray Absorption Fine Structure (EXAFS) Time-Dependent Perturbation Theory 192 Problems X-ray Photoelectron Spectroscopy Introduction Experimental Considerations Kinetic Energy of Photoelectrons Photoelectron Energy Spectrum Binding Energy and Final-State Effects Binding Energy Shifts Chemical Shifts Quantitative Analysis 210 Problems 211

5 x Contents 11. Radiative Transitions and the Electron Microprobe Introduction Nomenclature in X-Ray Spectroscopy Dipole Selection Rules Electron Microprobe Transition Rate for Spontaneous Emission Transition Rate for K a Emission in Ni Electron Microprobe: Quantitative Analysis Particle-Induced X-Ray Emission (PIXE) Evaluation of the Transition Probability for Radiative Transitions Calculation of the Kß/K a Ratio 230 Problems Nonradiative Transitions and Auger Electron Spectroscopy Introduction Auger Transitions Yield of Auger Electrons and Fluorescence Yield Atomic Level Width and Lifetimes Auger Electron Spectroscopy Quantitative Analysis Auger Depth Profiles 249 Problems Nuclear Techniques: Activation Analysis and Prompt Radiation Analysis Introduction Q Values and Kinetic Energies Radioactive Decay Radioactive Decay Law Radionuclide Production Activation Analysis Prompt Radiation Analysis 267 Problems Scanning Probe Microscopy Introduction Scanning Tunneling Microscopy Atomic Force Microscopy 284 Appendix 1. KM for 4 He + as Projectile and Integer Target Mass 291 Appendix 2. Rutherford Scattering Cross Section of the Elements forlmev 4 He+ 294 Appendix 3. 4 He + Stopping Cross Sections 296 Appendix 4. Electron Configurations and Ionization Potentials of Atoms 299 Appendix 5. Atomic Scattering Factors 302 Appendix 6. Electron Binding Energies 305

6 Contents xi Appendix 7. X-Ray Wavelengths (nm) 309 Appendix 8. Mass Absorption Coefficient and Densities 312 Appendix 9. KLL Auger Energies (ev) 316 Appendix 10. Table of the Elements 319 Appendix 11. Table of Fluoresence Yields for K, L, and M Shells 325 Appendix 12. Physical Constants, Conversions, and Useful Combinations 327 Appendix 13. Acronyms 328 Index 330 /