Ion Spectroscopies for Surface Analysis

Determining the elemental composition of surfaces is an essential measurement in characterizing solid surfaces. At present, many ap­ proaches may be applied for measuring the elemental and molecular composition of a surface. Each method has particular strengths and limitations that often are directly connected to the physical processes involved. Typically, atoms and molecules on the surface and in the near surface region may be excited by photons, electrons, ions, or neutrals, and the detected particles are emitted, ejected, or scattered ions or electrons. The purpose of this book is to bring together a discussion of the surface compositional analysis that depends on detecting scattered or sputtered ions, and the methods emphasized are those where instruments are commercially available for carrying out the analysis. For each topic treated, the physical principles, instrumentation, qualitative analysis, artifacts, quantitative analysis, applications, opportunities, and limita­ tions are discussed. The first chapter provides an overview of the role of elemental composition in surface science; compositional depth profiling; stimulation by an electric field, electrons, neutrals, or photons and detection of ions; and then stimulation by ions, and detection of ions, electrons, photons, or neutrals.

Contenu

1. Overview of Ion Spectroscopies for Surface Compositional Analysis.- Glossary of Acronyms.- 1. Purposes.- 2. Introduction.- 2.1. Role of Surface Analysis in Surface Characterization.- 2.1.1. Surface Area.- 2.1.2. Real and Clean Surfaces; Solid Forms.- 2.1.3. Structure and Topography.- 2.1.4. Surface Thermodynamics, Equilibrium Shape, and Diffusion.- 2.1.5. Amount Adsorbed and Nature of Adsorbate/Solid Interactions.- 2.1.6. Surface Composition or Purity.- 2.2. Surface Atom Density and Ultrahigh Vacuum.- 2.3. Compositional Depth Profiling.- 2.3.1. Sputtering Mechanism, Yield, and Rate.- 2.3.2. Instrumentation.- 2.3.3. Data Obtained and Typical Results.- 3. Overview of Compositional Surface Analysis by Ion Spectroscopies.- 3.1. Effects of Energetic Ion Impact on Surfaces.- 3.2. Stimulation and Detection in Ion Spectroscopies.- 4. Ion Spectroscopies Using Ion Stimulation.- 4.1. Ion Detection: SIMS, ISS, RBS, NRA, HFS.- 4.1.1. Secondary Ion Mass Spectrometry (SIMS).- 4.1.2. Ion Scattering Spectrometry (ISS).- 4.1.3. Rutherford Backscattering Spectrometry (RBS), Nuclear Reaction Analysis (NRA), and Hydrogen Forward Scattering Spectrometry (HFS).- 4.1.4. Comparisions of SIMS, SNMS, ISS, RBS, AES, and XPS.- 4.2. Photon Detection of Ion-Induced Radiation.- 4.2.1. Particle-Induced X-Ray Emission (PIXE).- 4.2.2. Bombardment-Induced Light Emission (BLE).- 4.3. Electron Detection; Ion Neutralization Spectroscopy (INS).- 4.4. Neutral (Postionized) Detection: SNMS, SALI, SARISA.- 5. Ion Spectroscopies Using Ion Detection.- 5.1. Electron Stimulation: ESD, ESDIAD, EPMA.- 5.1.1. Electron Stimulated Desorption (ESD).- 5.1.2. Electron Stimulated Desorption Ion Angular Distribution (ESDIAD).- 5.2. Photon Stimulation: LAMMA, LIMS.- 5.3. Neutral Stimulation: FAB-SIMS, NSS.- 5.4. Electric Field Stimulation: APFIM, FIMS.- References.- 2. Surface Structure and Reaction Studies by Ion-Solid Collisions.- 1. Introduction.- 2. The Experimental Approach.- 3. How to View the Process.- 3.1. Transport Theories.- 3.2. Molecular Dynamics Calculations.- 3.2.1. Yields.- 3.2.2. Energy and Angular Distributions.- 3.2.3. Clusters.- 3.2.4. Damage to the Substrate.- 3.3. Interaction Potentials.- 3.3.1. Repulsive Pair Potentials and the BCA.- 3.3.2. Attractive Pair Potentials.- 3.3.3. Many-Body Potentials-Metals and the Embedded Atom Method.- 3.3.4. Many-Body Potentials-Silicon and Covalent Solids.- 3.3.5. Many-Body Potentials-Reactions on Surfaces.- 3.3.6. Many-Body Potential-Molecular Solids.- 3.3.7. The Future.- 4. Electronic Effects.- 4.1. Tunneling Model.- 4.2. Bond-Breaking Model.- 4.3. Deexcitation Model for Sputtered Excited Neutral Atoms.- 5. Surface Characterization with Ion Bombardment.- 5.1. Surface Structure Studies.- 5.1.1. Trajectories of Substrate Species.- 5.1.2. Trajectories of Overlayer Species.- 5.1.3. Shadow-Cone Enhanced Desorption.- 5.2. Molecular Composition Studies.- 5.2.1. Intact Molecular Ejection.- 5.2.2. Molecular Recombination During Ejection.- 5.2.3. Prospects for Detection of Desorbed Neutral Molecules.- 6. Conclusions and Prospects.- References.- 3. Particle-Induced Desorption Ionization Techniques for Organic Mass Spectrometry.- 1. Introduction.- 1.1. Ionization Overview.- 1.1.1. Desorption Ionization.- 1.1.2. Nebulization Ionization.- 1.2. Historial Perspective.- 1.3. Instrumentation.- 1.3.1. Source Design.- 1.3.2. Mass Analyzers.- 1.3.3. Detection of Ions.- 2. Spectral Effects of Primary Beam Parameters.- 2.1. Observe or Reverse Irradiation.- 2.2. Angle of Incidence of Primary Beam.- 2.3. Charge State Dependence.- 2.4. Energy Dependence.- 2.4.1. Wavelength Dependence in Laser Desorption.- 2.4.2. Particle Mass and Velocity Dependences.- 2.5. Primary Particle Flux and Dose.- 3. Properties of Secondary Ions.- 3.1. Energy Distribution.- 3.2. Angular Distribution.- 3.3. Time Distribution.- 3.4. Charge Distribution.- 4. Sample Preparation.- 4.1. Neat Samples.- 4.2. Matrices for Sample Preparation.- 4.2.1. Solid Sample Matrices.- 4.2.2. Liquid Sample Matrices.- 4.3. Derivatization Techniques.- 4.3.1. Creation of Preformed Ions.- 4.3.2. Ion Management.- 5. Special Techniques.- 5.1. Chromatographic Interfaces.- 5.1.1. Dynamic Chromatography.- 5.1.2. Static Chromatography.- 5.2. Real Time Analysis.- 5.2.1. Simple Kinetic Studies.- 5.2.2. Catalyzed Reactions.- 5.3. High-Mass Analysis.- 5.3.1. Spectral Appearance.- 5.3.2. Spectral Interpretation.- 5.3.3. Strategies for Increased Mass Range.- 5.4. Mass Spectrometry/Mass Spectrometry.- 5.4.1. Novel Ion Structures.- 5.4.2. Mixture Analysis.- 6. Future Prospects.- References.- 4. Laser Resonant and Nonresonant Photoionization of Sputtered Neutrals.- Glossary of Symbols and Acronyms.- 1. Introduction.- 2. Photoionization.- 3. Experimental Details.- 3.1. Lasers.- 3.2. Ion Beam Systems and Mass Spectrometers.- 3.3. Detection Electronics.- 4. Artifacts, Quantitation, Capabilities, and Limitations.- 4.1. Resonantly Enhanced Multiphoton Ionization (REMPI).- 4.1.1. Inorganic Analyses.- 4.1.2. Organic Analyses.- 4.2. Nonresonant Multiphoton Ionization (NRMPI).- 4.3. Single-Photon Ionization (SPI).- 5. Applications.- 5.1. Depth Profiling of Bulk Material Using REMPI.- 5.2. Multielement Analysis by NRMPI.- 5.3. Depth Profiling of Bulk Material Using NRMPI.- 5.4. Interface Analysis with NRMPI.- 5.5. Analysis of Organic Compounds Using SPI and Ion Beam Desorption.- 5.6. Bulk Polymer Analysis Using SPI and Ion Beam Desorption.- 6. Future Directions.- 7. Summary.- References.- 5. Rutherford Backscattering and Nuclear Reaction Analysis.- 1. Introduction.- 2. Principles of the Methods.- 2.1. Rutherford Backscattering.- 2.1.1. Impact Parameter.- 2.1.2. Kinematics.- 2.1.3. Cross Sections.- 2.1.4. Scattering from the Bulk: Stopping Power.- 2.1.5. The Energy Spectrum.- 2.2. Nuclear Reaction Analysis.- 2.2.1. Kinematics.- 2.2.2. Cross Section.- 2.2.3. Tables of Nuclear Reactions.- 2.3. Hydrogen Detection.- 2.3.1. Forward Recoil Scattering.- 2.3.2. Nuclear Reactions.- 2. Apparatus.- 3.1. General Setup.- 3.2. A UHV Ion Scattering Chamber.- 3.3. Charged Particle Spectrometers.- 4. Quantitative Analysis and Sensitivity.- 4.1. Mass Resolution.- 4.2. Depth Resolution.- 4.3. Quantitative Analysis.- 4.4. Lateral Resolution.- 4.5. Beam Damage and Desorption.- 5. Ion Scattering as a Structural Tool.- 5.1. Shadowing.- 5.2. Channeling.- 5.3. The Surface Peak.- 5.4. Double Alignment and Transmission.- 6. Applications.- 7. Outstanding Strengths of RBS in Relation to AES, XPS, and SIMS.- References.- 6. Ion Scattering Spectroscopy.- 1. Introduction.- 2. Basic Principles.- 2.1. Parameter Range.- 2.2. Binary Collisions.- 2.2.1. Energy Spectrum.- 2…