An ideal text for students as well as practitioners, this is a comprehensive introduction to the field of scanning electron microscopy (SEM) and X-ray microanalysis. The text has been used in educating over 3,000 students at the Lehigh SEM short course as well as thousands of undergraduate and graduate students at universities across the globe. The authors emphasize the practical aspects of the techniques described. Topics discussed include user-controlled functions of scanning electron microscopes and x-ray spectrometers and the use of x-rays for qualitative and quantitative analysis. Separate chapters cover SEM sample preparation methods for hard materials, polymers, and biological specimens.
Klappentext
This text provides students as well as practitioners with a comprehensive introduction to the field of scanning electron microscopy (SEM) and X-ray microanalysis. The authors emphasize the practical aspects of the techniques described. Topics discussed include user-controlled functions of scanning electron microscopes and x-ray spectrometers and the use of x-rays for qualitative and quantitative analysis. Separate chapters cover SEM sample preparation methods for hard materials, polymers, and biological specimens. In addition techniques for the elimination of charging in non-conducting specimens are detailed.
Inhalt
1. Introduction.- 1.1. Imaging Capabilities.- 1.2. Structure Analysis.- 1.3. Elemental Analysis.- 1.4. Summary and Outline of This Book.- Appendix A. Overview of Scanning Electron Microscopy.- Appendix B. Overview of Electron Probe X-Ray Microanalysis.- References.- 2. The SEM and Its Modes of Operation.- 2.1. How the SEM Works.- 2.1.1. Functions of the SEM Subsystems.- 2.1.1.1. Electron Gun and Lenses Produce a Small Electron Beam.- 2.1.1.2. Deflection System Controls Magnification.- 2.1.1.3. Electron Detector Collects the Signal.- 2.1.1.4. Camera or Computer Records the Image.- 2.1.1.5. Operator Controls.- 2.1.2. SEM Imaging Modes.- 2.1.2.1. Resolution Mode.- 2.1.2.2. High-Current Mode.- 2.1.2.3. Depth-of-Focus Mode.- 2.1.2.4. Low-Voltage Mode.- 2.1.3. Why Learn about Electron Optics?.- 2.2. Electron Guns.- 2.2.1. Tungsten Hairpin Electron Guns.- 2.2.1.1. Filament.- 2.2.1.2. Grid Cap.- 2.2.1.3. Anode.- 2.2.1.4. Emission Current and Beam Current.- 2.2.1.5. Operator Control of the Electron Gun.- 2.2.2. Electron Gun Characteristics.- 2.2.2.1. Electron Emission Current.- 2.2.2.2. Brightness.- 2.2.2.3. Lifetime.- 2.2.2.4. Source Size, Energy Spread, Beam Stability.- 2.2.2.5. Improved Electron Gun Characteristics.- 2.2.3. Lanthanum Hexaboride (LaB6) Electron Guns.- 2.2.3.1. Introduction.- 2.2.3.2. Operation of the LaB6 Source.- 2.2.4. Field Emission Electron Guns.- 2.3. Electron Lenses.- 2.3.1. Making the Beam Smaller.- 2.3.1.1. Electron Focusing.- 2.3.1.2. Demagnification of the Beam.- 2.3.2. Lenses in SEMs.- 2.3.2.1. Condenser Lenses.- 2.3.2.2. Objective Lenses.- 2.3.2.3. Real and Virtual Objective Apertures.- 2.3.3. Operator Control of SEM Lenses.- 2.3.3.1. Effect of Aperture Size.- 2.3.3.2. Effect of Working Distance.- 2.3.3.3. Effect of Condenser Lens Strength.- 2.3.4. Gaussian Probe Diameter.- 2.3.5. Lens Aberrations.- 2.3.5.1. Spherical Aberration.- 2.3.5.2. Aperture Diffraction.- 2.3.5.3. Chromatic Aberration.- 2.3.5.4. Astigmatism.- 2.3.5.5. Aberrations in the Objective Lens.- 2.4. Electron Probe Diameter versus Electron Probe Current.- 2.4.1. Calculation of dmin and imax.- 2.4.1.1. Minimum Probe Size.- 2.4.1.2. Minimum Probe Size at 10-30 kV.- 2.4.1.3. Maximum Probe Current at 10-30 kV.- 2.4.1.4. Low-Voltage Operation.- 2.4.1.5. Graphical Summary.- 2.4.2. Performance in the SEM Modes.- 2.4.2.1. Resolution Mode.- 2.4.2.2. High-Current Mode.- 2.4.2.3. Depth-of-Focus Mode.- 2.4.2.4. Low-Voltage SEM.- 2.4.2.5. Environmental Barriers to High-Resolution Imaging.- References.- 3. Electron Beam-Specimen Interactions.- 3.1. The Story So Far.- 3.2. The Beam Enters the Specimen.- 3.3. The Interaction Volume.- 3.3.1. Visualizing the Interaction Volume.- 3.3.2. Simulating the Interaction Volume.- 3.3.3. Influence of Beam and Specimen Parameters on the Interaction Volume.- 3.3.3.1. Influence of Beam Energy on the Interaction Volume.- 3.3.3.2. Influence of Atomic Number on the Interaction Volume.- 3.3.3.3. Influence of Specimen Surface Tilt on the Interaction Volume.- 3.3.4. Electron Range: A Simple Measure of the Interaction Volume.- 3.3.4.1. Introduction.- 3.3.4.2. The Electron Range at Low Beam Energy.- 3.4. Imaging Signals from the Interaction Volume.- 3.4.1. Backscattered Electrons.- 3.4.1.1. Atomic Number Dependence of BSE.- 3.4.1.2. Beam Energy Dependence of BSE.- 3.4.1.3. Tilt Dependence of BSE.- 3.4.1.4. Angular Distribution of BSE.- 3.4.1.5. Energy Distribution of BSE.- 3.4.1.6. Lateral Spatial Distribution of BSE.- 3.4.1.7. Sampling Depth of BSE.- 3.4.2. Secondary Electrons.- 3.4.2.1. Definition and Origin of SE.- 3.4.2.2. SE Yield with Primary Beam Energy.- 3.4.2.3. SE Energy Distribution.- 3.4.2.4. Range and Escape Depth of SE.- 3.4.2.5. Relative Contributions of SE1 and SE2.- 3.4.2.6. Specimen Composition Dependence of SE.- 3.4.2.7. Specimen Tilt Dependence of SE.- 3.4.2.8. Angular Distribution of SE.- References.- 4. Image Formation and Interpretation.- 4.1. The Story So Far.- 4.2. The Basic SEM Imaging Process.- 4.2.1. Scanning Action.- 4.2.2. Image Construction (Mapping).- 4.2.2.1. Line Scans.- 4.2.2.2. Image (Area) Scanning.- 4.2.2.3. Digital Imaging: Collection and Display.- 4.2.3. Magnification.- 4.2.4. Picture Element (Pixel) Size.- 4.2.5. Low-Magnification Operation.- 4.2.6. Depth of Field (Focus).- 4.2.7. Image Distortion.- 4.2.7.1. Projection Distortion: Gnomonic Projection.- 4.2.7.2. Projection Distortion: Image Foreshortening.- 4.2.7.3. Scan Distortion: Pathological Defects.- 4.2.7.4. Moiré Effects.- 4.3. Detectors.- 4.3.1. Introduction.- 4.3.2. Electron Detectors.- 4.3.2.1. Everhart-Thornley Detector.- 4.3.2.2. "Through-the-Lens" (TTL) Detector.- 4.3.2.3. Dedicated Backscattered Electron Detectors.- 4.4. The Roles of the Specimen and Detector in Contrast Formation.- 4.4.1. Contrast.- 4.4.2. Compositional (Atomic Number) Contrast.- 4.4.2.1. Introduction.- 4.4.2.2. Compositional Contrast with Backscattered Electrons.- 4.4.3. Topographic Contrast.- 4.4.3.1. Origins of Topographic Contrast.- 4.4.3.2. Topographic Contrast with the Everhart-Thornley Detector.- 4.4.3.3. Light-Optical Analogy.- 4.4.3.4. Interpreting Topographic Contrast with Other Detectors.- 4.5. Image Quality.- 4.6. Image Processing for the Display of Contrast Information.- 4.6.1. The Signal Chain.- 4.6.2. The Visibility Problem.- 4.6.3. Analog and Digital Image Processing.- 4.6.4. Basic Digital Image Processing.- 4.6.4.1. Digital Image Enhancement.- 4.6.4.2. Digital Image Measurements.- References.- 5. Special Topics in Scanning Electron Microscopy.- 5.1. High-Resolution Imaging.- 5.1.1. The Resolution Problem.- 5.1.2. Achieving High Resolution at High Beam Energy.- 5.1.3. High-Resolution Imaging at Low Voltage.- 5.2. STEM-in-SEM: High Resolution for the Special Case of Thin Specimens.- 5.3. Surface Imaging at Low Voltage.- 5.4. Making Dimensional Measurements in the SEM.- 5.5. Recovering the Third Dimension: Stereomicroscopy.- 5.5.1. Qualitative Stereo Imaging and Presentation.- 5.5.2. Quantitative Stereo Microscopy.- 5.6. Variable-Pressure and Environmental SEM.- 5.6.1. Current Instruments.- 5.6.2. Gas in the Specimen Chamber.- 5.6.2.1. Units of Gas Pressure.- 5.6.2.2. The Vacuum System.- 5.6.3. Electron Interactions with Gases.- 5.6.4. The Effect of the Gas on Charging.- 5.6.5. Imaging in the ESEM and the VPSEM.- 5.6.6. X-Ray Microanalysis in the Presence of a Gas.- 5.7. Special Contrast Mechanisms.- 5.7.1. Electric Fields.- 5.7.2. Magnetic Fields.- 5.7.2.1. Type 1 Magnetic Contrast.- 5.7.2.2. Type 2 Magnetic Contrast.- 5.7.3. Crystallographic Contrast.- 5.8. Electron Backscatter…