- •Preface
- •Imaging Microscopic Features
- •Measuring the Crystal Structure
- •References
- •Contents
- •1.4 Simulating the Effects of Elastic Scattering: Monte Carlo Calculations
- •What Are the Main Features of the Beam Electron Interaction Volume?
- •How Does the Interaction Volume Change with Composition?
- •How Does the Interaction Volume Change with Incident Beam Energy?
- •How Does the Interaction Volume Change with Specimen Tilt?
- •1.5 A Range Equation To Estimate the Size of the Interaction Volume
- •References
- •2: Backscattered Electrons
- •2.1 Origin
- •2.2.1 BSE Response to Specimen Composition (η vs. Atomic Number, Z)
- •SEM Image Contrast with BSE: “Atomic Number Contrast”
- •SEM Image Contrast: “BSE Topographic Contrast—Number Effects”
- •2.2.3 Angular Distribution of Backscattering
- •Beam Incident at an Acute Angle to the Specimen Surface (Specimen Tilt > 0°)
- •SEM Image Contrast: “BSE Topographic Contrast—Trajectory Effects”
- •2.2.4 Spatial Distribution of Backscattering
- •Depth Distribution of Backscattering
- •Radial Distribution of Backscattered Electrons
- •2.3 Summary
- •References
- •3: Secondary Electrons
- •3.1 Origin
- •3.2 Energy Distribution
- •3.3 Escape Depth of Secondary Electrons
- •3.8 Spatial Characteristics of Secondary Electrons
- •References
- •4: X-Rays
- •4.1 Overview
- •4.2 Characteristic X-Rays
- •4.2.1 Origin
- •4.2.2 Fluorescence Yield
- •4.2.3 X-Ray Families
- •4.2.4 X-Ray Nomenclature
- •4.2.6 Characteristic X-Ray Intensity
- •Isolated Atoms
- •X-Ray Production in Thin Foils
- •X-Ray Intensity Emitted from Thick, Solid Specimens
- •4.3 X-Ray Continuum (bremsstrahlung)
- •4.3.1 X-Ray Continuum Intensity
- •4.3.3 Range of X-ray Production
- •4.4 X-Ray Absorption
- •4.5 X-Ray Fluorescence
- •References
- •5.1 Electron Beam Parameters
- •5.2 Electron Optical Parameters
- •5.2.1 Beam Energy
- •Landing Energy
- •5.2.2 Beam Diameter
- •5.2.3 Beam Current
- •5.2.4 Beam Current Density
- •5.2.5 Beam Convergence Angle, α
- •5.2.6 Beam Solid Angle
- •5.2.7 Electron Optical Brightness, β
- •Brightness Equation
- •5.2.8 Focus
- •Astigmatism
- •5.3 SEM Imaging Modes
- •5.3.1 High Depth-of-Field Mode
- •5.3.2 High-Current Mode
- •5.3.3 Resolution Mode
- •5.3.4 Low-Voltage Mode
- •5.4 Electron Detectors
- •5.4.1 Important Properties of BSE and SE for Detector Design and Operation
- •Abundance
- •Angular Distribution
- •Kinetic Energy Response
- •5.4.2 Detector Characteristics
- •Angular Measures for Electron Detectors
- •Elevation (Take-Off) Angle, ψ, and Azimuthal Angle, ζ
- •Solid Angle, Ω
- •Energy Response
- •Bandwidth
- •5.4.3 Common Types of Electron Detectors
- •Backscattered Electrons
- •Passive Detectors
- •Scintillation Detectors
- •Semiconductor BSE Detectors
- •5.4.4 Secondary Electron Detectors
- •Everhart–Thornley Detector
- •Through-the-Lens (TTL) Electron Detectors
- •TTL SE Detector
- •TTL BSE Detector
- •Measuring the DQE: BSE Semiconductor Detector
- •References
- •6: Image Formation
- •6.1 Image Construction by Scanning Action
- •6.2 Magnification
- •6.3 Making Dimensional Measurements With the SEM: How Big Is That Feature?
- •Using a Calibrated Structure in ImageJ-Fiji
- •6.4 Image Defects
- •6.4.1 Projection Distortion (Foreshortening)
- •6.4.2 Image Defocusing (Blurring)
- •6.5 Making Measurements on Surfaces With Arbitrary Topography: Stereomicroscopy
- •6.5.1 Qualitative Stereomicroscopy
- •Fixed beam, Specimen Position Altered
- •Fixed Specimen, Beam Incidence Angle Changed
- •6.5.2 Quantitative Stereomicroscopy
- •Measuring a Simple Vertical Displacement
- •References
- •7: SEM Image Interpretation
- •7.1 Information in SEM Images
- •7.2.2 Calculating Atomic Number Contrast
- •Establishing a Robust Light-Optical Analogy
- •Getting It Wrong: Breaking the Light-Optical Analogy of the Everhart–Thornley (Positive Bias) Detector
- •Deconstructing the SEM/E–T Image of Topography
- •SUM Mode (A + B)
- •DIFFERENCE Mode (A−B)
- •References
- •References
- •9: Image Defects
- •9.1 Charging
- •9.1.1 What Is Specimen Charging?
- •9.1.3 Techniques to Control Charging Artifacts (High Vacuum Instruments)
- •Observing Uncoated Specimens
- •Coating an Insulating Specimen for Charge Dissipation
- •Choosing the Coating for Imaging Morphology
- •9.2 Radiation Damage
- •9.3 Contamination
- •References
- •10: High Resolution Imaging
- •10.2 Instrumentation Considerations
- •10.4.1 SE Range Effects Produce Bright Edges (Isolated Edges)
- •10.4.4 Too Much of a Good Thing: The Bright Edge Effect Hinders Locating the True Position of an Edge for Critical Dimension Metrology
- •10.5.1 Beam Energy Strategies
- •Low Beam Energy Strategy
- •High Beam Energy Strategy
- •Making More SE1: Apply a Thin High-δ Metal Coating
- •Making Fewer BSEs, SE2, and SE3 by Eliminating Bulk Scattering From the Substrate
- •10.6 Factors That Hinder Achieving High Resolution
- •10.6.2 Pathological Specimen Behavior
- •Contamination
- •Instabilities
- •References
- •11: Low Beam Energy SEM
- •11.3 Selecting the Beam Energy to Control the Spatial Sampling of Imaging Signals
- •11.3.1 Low Beam Energy for High Lateral Resolution SEM
- •11.3.2 Low Beam Energy for High Depth Resolution SEM
- •11.3.3 Extremely Low Beam Energy Imaging
- •References
- •12.1.1 Stable Electron Source Operation
- •12.1.2 Maintaining Beam Integrity
- •12.1.4 Minimizing Contamination
- •12.3.1 Control of Specimen Charging
- •12.5 VPSEM Image Resolution
- •References
- •13: ImageJ and Fiji
- •13.1 The ImageJ Universe
- •13.2 Fiji
- •13.3 Plugins
- •13.4 Where to Learn More
- •References
- •14: SEM Imaging Checklist
- •14.1.1 Conducting or Semiconducting Specimens
- •14.1.2 Insulating Specimens
- •14.2 Electron Signals Available
- •14.2.1 Beam Electron Range
- •14.2.2 Backscattered Electrons
- •14.2.3 Secondary Electrons
- •14.3 Selecting the Electron Detector
- •14.3.2 Backscattered Electron Detectors
- •14.3.3 “Through-the-Lens” Detectors
- •14.4 Selecting the Beam Energy for SEM Imaging
- •14.4.4 High Resolution SEM Imaging
- •Strategy 1
- •Strategy 2
- •14.5 Selecting the Beam Current
- •14.5.1 High Resolution Imaging
- •14.5.2 Low Contrast Features Require High Beam Current and/or Long Frame Time to Establish Visibility
- •14.6 Image Presentation
- •14.6.1 “Live” Display Adjustments
- •14.6.2 Post-Collection Processing
- •14.7 Image Interpretation
- •14.7.1 Observer’s Point of View
- •14.7.3 Contrast Encoding
- •14.8.1 VPSEM Advantages
- •14.8.2 VPSEM Disadvantages
- •15: SEM Case Studies
- •15.1 Case Study: How High Is That Feature Relative to Another?
- •15.2 Revealing Shallow Surface Relief
- •16.1.2 Minor Artifacts: The Si-Escape Peak
- •16.1.3 Minor Artifacts: Coincidence Peaks
- •16.1.4 Minor Artifacts: Si Absorption Edge and Si Internal Fluorescence Peak
- •16.2 “Best Practices” for Electron-Excited EDS Operation
- •16.2.1 Operation of the EDS System
- •Choosing the EDS Time Constant (Resolution and Throughput)
- •Choosing the Solid Angle of the EDS
- •Selecting a Beam Current for an Acceptable Level of System Dead-Time
- •16.3.1 Detector Geometry
- •16.3.2 Process Time
- •16.3.3 Optimal Working Distance
- •16.3.4 Detector Orientation
- •16.3.5 Count Rate Linearity
- •16.3.6 Energy Calibration Linearity
- •16.3.7 Other Items
- •16.3.8 Setting Up a Quality Control Program
- •Using the QC Tools Within DTSA-II
- •Creating a QC Project
- •Linearity of Output Count Rate with Live-Time Dose
- •Resolution and Peak Position Stability with Count Rate
- •Solid Angle for Low X-ray Flux
- •Maximizing Throughput at Moderate Resolution
- •References
- •17: DTSA-II EDS Software
- •17.1 Getting Started With NIST DTSA-II
- •17.1.1 Motivation
- •17.1.2 Platform
- •17.1.3 Overview
- •17.1.4 Design
- •Simulation
- •Quantification
- •Experiment Design
- •Modeled Detectors (. Fig. 17.1)
- •Window Type (. Fig. 17.2)
- •The Optimal Working Distance (. Figs. 17.3 and 17.4)
- •Elevation Angle
- •Sample-to-Detector Distance
- •Detector Area
- •Crystal Thickness
- •Number of Channels, Energy Scale, and Zero Offset
- •Resolution at Mn Kα (Approximate)
- •Azimuthal Angle
- •Gold Layer, Aluminum Layer, Nickel Layer
- •Dead Layer
- •Zero Strobe Discriminator (. Figs. 17.7 and 17.8)
- •Material Editor Dialog (. Figs. 17.9, 17.10, 17.11, 17.12, 17.13, and 17.14)
- •17.2.1 Introduction
- •17.2.2 Monte Carlo Simulation
- •17.2.4 Optional Tables
- •References
- •18: Qualitative Elemental Analysis by Energy Dispersive X-Ray Spectrometry
- •18.1 Quality Assurance Issues for Qualitative Analysis: EDS Calibration
- •18.2 Principles of Qualitative EDS Analysis
- •Exciting Characteristic X-Rays
- •Fluorescence Yield
- •X-ray Absorption
- •Si Escape Peak
- •Coincidence Peaks
- •18.3 Performing Manual Qualitative Analysis
- •Beam Energy
- •Choosing the EDS Resolution (Detector Time Constant)
- •Obtaining Adequate Counts
- •18.4.1 Employ the Available Software Tools
- •18.4.3 Lower Photon Energy Region
- •18.4.5 Checking Your Work
- •18.5 A Worked Example of Manual Peak Identification
- •References
- •19.1 What Is a k-ratio?
- •19.3 Sets of k-ratios
- •19.5 The Analytical Total
- •19.6 Normalization
- •19.7.1 Oxygen by Assumed Stoichiometry
- •19.7.3 Element by Difference
- •19.8 Ways of Reporting Composition
- •19.8.1 Mass Fraction
- •19.8.2 Atomic Fraction
- •19.8.3 Stoichiometry
- •19.8.4 Oxide Fractions
- •Example Calculations
- •19.9 The Accuracy of Quantitative Electron-Excited X-ray Microanalysis
- •19.9.1 Standards-Based k-ratio Protocol
- •19.9.2 “Standardless Analysis”
- •19.10 Appendix
- •19.10.1 The Need for Matrix Corrections To Achieve Quantitative Analysis
- •19.10.2 The Physical Origin of Matrix Effects
- •19.10.3 ZAF Factors in Microanalysis
- •X-ray Generation With Depth, φ(ρz)
- •X-ray Absorption Effect, A
- •X-ray Fluorescence, F
- •References
- •20.2 Instrumentation Requirements
- •20.2.1 Choosing the EDS Parameters
- •EDS Spectrum Channel Energy Width and Spectrum Energy Span
- •EDS Time Constant (Resolution and Throughput)
- •EDS Calibration
- •EDS Solid Angle
- •20.2.2 Choosing the Beam Energy, E0
- •20.2.3 Measuring the Beam Current
- •20.2.4 Choosing the Beam Current
- •Optimizing Analysis Strategy
- •20.3.4 Ba-Ti Interference in BaTiSi3O9
- •20.4 The Need for an Iterative Qualitative and Quantitative Analysis Strategy
- •20.4.2 Analysis of a Stainless Steel
- •20.5 Is the Specimen Homogeneous?
- •20.6 Beam-Sensitive Specimens
- •20.6.1 Alkali Element Migration
- •20.6.2 Materials Subject to Mass Loss During Electron Bombardment—the Marshall-Hall Method
- •Thin Section Analysis
- •Bulk Biological and Organic Specimens
- •References
- •21: Trace Analysis by SEM/EDS
- •21.1 Limits of Detection for SEM/EDS Microanalysis
- •21.2.1 Estimating CDL from a Trace or Minor Constituent from Measuring a Known Standard
- •21.2.2 Estimating CDL After Determination of a Minor or Trace Constituent with Severe Peak Interference from a Major Constituent
- •21.3 Measurements of Trace Constituents by Electron-Excited Energy Dispersive X-ray Spectrometry
- •The Inevitable Physics of Remote Excitation Within the Specimen: Secondary Fluorescence Beyond the Electron Interaction Volume
- •Simulation of Long-Range Secondary X-ray Fluorescence
- •NIST DTSA II Simulation: Vertical Interface Between Two Regions of Different Composition in a Flat Bulk Target
- •NIST DTSA II Simulation: Cubic Particle Embedded in a Bulk Matrix
- •21.5 Summary
- •References
- •22.1.2 Low Beam Energy Analysis Range
- •22.2 Advantage of Low Beam Energy X-Ray Microanalysis
- •22.2.1 Improved Spatial Resolution
- •22.3 Challenges and Limitations of Low Beam Energy X-Ray Microanalysis
- •22.3.1 Reduced Access to Elements
- •22.3.3 At Low Beam Energy, Almost Everything Is Found To Be Layered
- •Analysis of Surface Contamination
- •References
- •23: Analysis of Specimens with Special Geometry: Irregular Bulk Objects and Particles
- •23.2.1 No Chemical Etching
- •23.3 Consequences of Attempting Analysis of Bulk Materials With Rough Surfaces
- •23.4.1 The Raw Analytical Total
- •23.4.2 The Shape of the EDS Spectrum
- •23.5 Best Practices for Analysis of Rough Bulk Samples
- •23.6 Particle Analysis
- •Particle Sample Preparation: Bulk Substrate
- •The Importance of Beam Placement
- •Overscanning
- •“Particle Mass Effect”
- •“Particle Absorption Effect”
- •The Analytical Total Reveals the Impact of Particle Effects
- •Does Overscanning Help?
- •23.6.6 Peak-to-Background (P/B) Method
- •Specimen Geometry Severely Affects the k-ratio, but Not the P/B
- •Using the P/B Correspondence
- •23.7 Summary
- •References
- •24: Compositional Mapping
- •24.2 X-Ray Spectrum Imaging
- •24.2.1 Utilizing XSI Datacubes
- •24.2.2 Derived Spectra
- •SUM Spectrum
- •MAXIMUM PIXEL Spectrum
- •24.3 Quantitative Compositional Mapping
- •24.4 Strategy for XSI Elemental Mapping Data Collection
- •24.4.1 Choosing the EDS Dead-Time
- •24.4.2 Choosing the Pixel Density
- •24.4.3 Choosing the Pixel Dwell Time
- •“Flash Mapping”
- •High Count Mapping
- •References
- •25.1 Gas Scattering Effects in the VPSEM
- •25.1.1 Why Doesn’t the EDS Collimator Exclude the Remote Skirt X-Rays?
- •25.2 What Can Be Done To Minimize gas Scattering in VPSEM?
- •25.2.2 Favorable Sample Characteristics
- •Particle Analysis
- •25.2.3 Unfavorable Sample Characteristics
- •References
- •26.1 Instrumentation
- •26.1.2 EDS Detector
- •26.1.3 Probe Current Measurement Device
- •Direct Measurement: Using a Faraday Cup and Picoammeter
- •A Faraday Cup
- •Electrically Isolated Stage
- •Indirect Measurement: Using a Calibration Spectrum
- •26.1.4 Conductive Coating
- •26.2 Sample Preparation
- •26.2.1 Standard Materials
- •26.2.2 Peak Reference Materials
- •26.3 Initial Set-Up
- •26.3.1 Calibrating the EDS Detector
- •Selecting a Pulse Process Time Constant
- •Energy Calibration
- •Quality Control
- •Sample Orientation
- •Detector Position
- •Probe Current
- •26.4 Collecting Data
- •26.4.1 Exploratory Spectrum
- •26.4.2 Experiment Optimization
- •26.4.3 Selecting Standards
- •26.4.4 Reference Spectra
- •26.4.5 Collecting Standards
- •26.4.6 Collecting Peak-Fitting References
- •26.5 Data Analysis
- •26.5.2 Quantification
- •26.6 Quality Check
- •Reference
- •27.2 Case Study: Aluminum Wire Failures in Residential Wiring
- •References
- •28: Cathodoluminescence
- •28.1 Origin
- •28.2 Measuring Cathodoluminescence
- •28.3 Applications of CL
- •28.3.1 Geology
- •Carbonado Diamond
- •Ancient Impact Zircons
- •28.3.2 Materials Science
- •Semiconductors
- •Lead-Acid Battery Plate Reactions
- •28.3.3 Organic Compounds
- •References
- •29.1.1 Single Crystals
- •29.1.2 Polycrystalline Materials
- •29.1.3 Conditions for Detecting Electron Channeling Contrast
- •Specimen Preparation
- •Instrument Conditions
- •29.2.1 Origin of EBSD Patterns
- •29.2.2 Cameras for EBSD Pattern Detection
- •29.2.3 EBSD Spatial Resolution
- •29.2.5 Steps in Typical EBSD Measurements
- •Sample Preparation for EBSD
- •Align Sample in the SEM
- •Check for EBSD Patterns
- •Adjust SEM and Select EBSD Map Parameters
- •Run the Automated Map
- •29.2.6 Display of the Acquired Data
- •29.2.7 Other Map Components
- •29.2.10 Application Example
- •Application of EBSD To Understand Meteorite Formation
- •29.2.11 Summary
- •Specimen Considerations
- •EBSD Detector
- •Selection of Candidate Crystallographic Phases
- •Microscope Operating Conditions and Pattern Optimization
- •Selection of EBSD Acquisition Parameters
- •Collect the Orientation Map
- •References
- •30.1 Introduction
- •30.2 Ion–Solid Interactions
- •30.3 Focused Ion Beam Systems
- •30.5 Preparation of Samples for SEM
- •30.5.1 Cross-Section Preparation
- •30.5.2 FIB Sample Preparation for 3D Techniques and Imaging
- •30.6 Summary
- •References
- •31: Ion Beam Microscopy
- •31.1 What Is So Useful About Ions?
- •31.2 Generating Ion Beams
- •31.3 Signal Generation in the HIM
- •31.5 Patterning with Ion Beams
- •31.7 Chemical Microanalysis with Ion Beams
- •References
- •Appendix
- •A Database of Electron–Solid Interactions
- •A Database of Electron–Solid Interactions
- •Introduction
- •Backscattered Electrons
- •Secondary Yields
- •Stopping Powers
- •X-ray Ionization Cross Sections
- •Conclusions
- •References
- •Index
- •Reference List
- •Index
References
. Fig. 21.19 Example with a pyramid of high purity SrF2 as the scattering target surrounded by a carbon tab (1 cm diameter) on a 2.5 cm diameter brass (Cu and Zn) disk. The Ni signal that is observed likely arises from the Ni-coatings of the specimen stage components
C K |
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21.5\ Summary
C
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Remote scattering peaks
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High count EDS spectra can be used to achieve limits of detection approaching a mass concentration of CDL = 0.0001 (100 ppm) when there are no peak interferences from higher concentration constituents, and CDL = 0.0005 (500 ppm) when significant peak interference does occur. However, the analyst must carefully test the SEM/EDS measurement environment to ensure that the trace measurement is meaningful and not a consequence of pathological remote scattering effects.
Currie LA (1968) Limits for qualitative detection and quantitative determination. Anal Chem 40:586–593
Newbury DE, Ritchie NWM (2016) Measurement of trace constituents by electron-excited X-ray microanalysis with energy dispersive spectrometry. Micros Microanal 22(3):520–535
Williams DB, Goldstein JI (1981) Artifacts encountered in energy dispersive X-ray spectrometry in the analytical electron microscope. In: Heinrich KFJ, Newbury DE, Myklebust RL, Fiori CE (eds) Energy dispersive X-ray spectrometry, National Bureau of Standards Special Publication 604 (U.S. Department of Commerce, Washington, DC), pp 341–349
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Low Beam Energy X-Ray
Microanalysis
22.1\ What Constitutes “Low” Beam Energy X-Ray Microanalysis? – 360
22.1.1\ Characteristic X-ray Peak Selection Strategy for Analysis – 364 22.1.2\ Low Beam Energy Analysis Range – 364
22.2\ Advantage of Low Beam Energy X-Ray Microanalysis – 365
22.2.1\ Improved Spatial Resolution – 365
22.2.2\ Reduced Matrix Absorption Correction – 366 22.2.3\ Accurate Analysis of Low Atomic Number Elements
at Low Beam Energy – 366
22.3\ Challenges and Limitations of Low Beam Energy X-Ray Microanalysis – 369
22.3.1\ Reduced Access to Elements – 369
22.3.2\ Relative Depth of X-Ray Generation: Susceptibility to Vertical Heterogeneity – 372
22.3.3\ At Low Beam Energy, Almost Everything Is Found To Be Layered – 373
References – 380
© Springer Science+Business Media LLC 2018
J. Goldstein et al., Scanning Electron Microscopy and X-Ray Microanalysis, https://doi.org/10.1007/978-1-4939-6676-9_22
360\ Chapter 22 · Low Beam Energy X-Ray Microanalysis
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|
|
|
Overvoltage |
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|
||||
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|
|
22.1 · What Constitutes “Low” Beam Energy X-Ray Microanalysis?
|
|
Same scale |
|
|
Si |
|
|
|
|
100000 |
|
|
|
|
|
|
|
|
10000 |
|
O |
|
|
|
|
|
Counts |
|
C |
|
|
|
Si |
|
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|
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|
|||
1000 |
|
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||
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|
|
100 |
|
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|
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Si |
|
|
|
10 |
|
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|
|
0.0 |
0.5 |
1.0 |
1.5 |
2.0 |
2.5 |
3.0 |
|
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|
|
|
Photon energy (keV) |
|
|
|
|
Same scale |
|
|
Si |
|
|
|
|
40000 |
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|
|
Counts |
30000 |
|
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20000 |
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O |
|
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10000 |
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C |
|
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Si |
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0 |
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0.0 |
0.5 |
1.0 |
1.5 |
2.0 |
2.5 |
3.0 |
|
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|
|
|
Photon energy (keV) |
|
|
361 |
|
22 |
|
|
|
Si_5keV
Si_4keV
Si_3keV
Si_2.8keV
Si_2.6keV
Si_2.4keV
Si_2.2keV
Si_2.0keV
Si_1.9keV
3.5 |
4.0 |
4.5 |
5.0 |
Si |
|
|
Si_5keV |
|
|
Si_4keV |
|
5 keV |
|
|
Si_3keV |
|
|
Si_2.8keV |
|
4 keV |
|
|
Si_2.6keV |
|
|
Si_2.4keV |
|
3 keV |
|
|
Si_2.2keV |
|
|
Si_2.0keV |
|
2.8 keV |
|
|
Si_1.9keV |
|
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|
|
2.6 keV |
|
|
|
2.4 keV |
|
|
|
2.2 keV |
|
|
|
2.0 keV |
|
|
|
1.9 keV |
|
|
|
3.5 |
4.0 |
4.5 |
5.0 |
. Fig. 22.2 Silicon at various incident beam energies from 5 keV to 1.9 keV showing the decrease in the peak-to-background with decreasing overvoltage
. Fig. 22.3 Periodic table illustrating X-ray shell choices for developing analysis strategy within the conventional beam energy range, E0 = 20 keV (Newbury and Ritchie, 2016)
Elemental measurement strategy for conventional beam energy analysis |
|
|
E0 = 20 keV |
Principal shell used for identification |
|
|
K-L |
|
U0 > 1.25 (Ec < 16 keV) |
K-shell |
|
|
|
|
EDS resolution: 129 eV (FWHM, MnKα) |
L-shell |
L-M |
|
||
|
|
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|
|
Not detectable |
|
M-shell |
|
H |
|
He |
||||
|
|
|
|
|||
Li |
Be |
|
|
Marginally detectable |
|
|
|
B |
C |
N |
O |
F |
Ne |
||||
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||||||||
Na |
Mg |
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|
|
Al |
Si |
P |
S |
Cl |
Ar |
K |
Ca |
Sc |
Ti |
V |
Cr |
Mn |
Fe |
Co |
Ni |
Cu |
Zn |
Ga |
Ge |
As |
Se |
Br |
Kr |
Rb |
Sr |
Y |
Zr |
Nb |
Mo |
Tc |
Ru |
Rh |
Pd |
Ag |
Cd |
In |
Sn |
Sb |
Te |
I |
Xe |
Cs |
Ba |
La |
Hf |
Ta |
W |
Re |
Os |
Ir |
Pt |
Au |
Hg |
Tl |
Pb |
Bi |
Po |
At |
Rn |
Fr |
Ra |
Ac |
|
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|
|
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|
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|
|
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|
|
Ce |
Pr |
Nd |
Pm |
Sm |
Eu |
Gd |
Tb |
Dy |
Ho |
Er |
Tm |
Yb |
Lu |
Th |
Pa |
U |
Np |
Pu |
Am |
Cm |
Bk |
Cf |
Es |
Fm |
Md |
No |
Lr |
362\ Chapter 22 · Low Beam Energy X-Ray Microanalysis
. Fig. 22.4 Periodic table illustrating X-ray shell choices for developing analysis strategy at the lower end of the conventional beam energy range, E0 = 10 keV (Newbury and Ritchie, 2016)
Elemental measurement strategy for conventional beam energy analysis
E0 = 10 keV |
|
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|
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Principal shell used for identification |
||||||||||
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|
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K-shell |
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K-L |
||||
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|
||||||
U0 > 1.25 (Ec < 8 keV) |
|
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|
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|
|||||||
EDS resolution: 129 eV (FWHM, MnKα) |
|
|
|
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|
|
L-shell |
|
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|
|
L-M |
||||||||
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|||||||||||
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||||
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||
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|
|
Not detectable |
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|
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M-shell |
|
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|||
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|||||
H |
|
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He |
|||||
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|
|
Marginally detectable |
|
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||||||
|
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|||||
Li |
Be |
|
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|
|
B |
C |
N |
O |
F |
|
Ne |
|||||||
|
|
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|
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|||||||||||||||
|
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||||||||||
Na |
Mg |
|
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|
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Al |
Si |
P |
S |
Cl |
|
Ar |
||
|
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|
|
|
|
|
||||||||||
K |
Ca |
Sc |
Ti |
V |
Cr |
Mn |
Fe |
|
Co |
Ni |
Cu |
Zn |
Ga |
Ge |
As |
Se |
Br |
|
Kr |
||
Rb |
Sr |
Y |
Zr |
Nb |
Mo |
Tc |
Ru |
|
Rh |
Pd |
Ag |
Cd |
In |
Sn |
Sb |
Te |
I |
|
Xe |
||
Cs |
Ba |
La |
Hf |
Ta |
W |
Re |
Os |
|
Ir |
Pt |
Au |
Hg |
Tl |
Pb |
Bi |
Po |
At |
|
Rn |
||
Fr |
Ra |
Ac |
|
|
|
|
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|
|
|
|
|
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|
|
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|
|
|
|
|
|
|
|
|
Ce |
Pr |
Nd |
Pm |
|
Sm |
Eu |
Gd |
Tb |
Dy |
Ho |
Er |
Tm |
Yb |
|
Lu |
||
|
|
|
|
Th |
Pa |
U |
Np |
|
Pu |
Am |
Cm |
Bk |
Cf |
Es |
Fm |
Md |
No |
|
Lr |
||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
. Fig. 22.5 Periodic table illustrating X-ray shell choices for developing analysis strategy for the upper end of the low beam energy range, E0 = 5 keV (Newbury and Ritchie, 2016)
Elemental measurement strategy for low beam energy analysis |
|
|
|||
E0 = 5 keV |
Principal shell used for identification |
||||
|
|
K-shell |
|
K-L |
|
|
|
|
|||
U0 > 1.25 (Ec < 4.0 keV) |
|
|
|
||
EDS resolution: 129 eV (FWHM, MnKα) |
|
|
L-shell |
|
L-M |
|
|
|
|||
|
|
|
|
||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Not detectable |
|
M-shell |
|
|||||||
H |
|
|
|
|||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
He |
||||
|
|
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|
|
|
|
|
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|
|
|||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Li |
Be |
|
|
|
Marginally detectable: |
B |
C |
|
N |
|
O |
|
F |
|
Ne |
|
|
|
|
|
|
|
|||||||||||
|
|
|
1 < U0 ≤ 1.25 or weak emission |
|
|
|
||||||||||
|
|
|
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|
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|
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|
|
Na |
Mg |
|
|
|
|
|
|
|
|
|
|
Al |
Si |
P |
S |
Cl |
Ar |
K |
Ca |
Sc |
Ti |
V |
Cr |
Mn |
Fe |
Co |
Ni |
Cu |
Zn |
Ga |
Ge |
As |
Se |
Br |
Kr |
Rb |
Sr |
Y |
Zr |
Nb |
Mo |
Tc |
Ru |
Rh |
Pd |
Ag |
Cd |
In |
Sn |
Sb |
Te |
I |
Xe |
Cs |
Ba |
La |
Hf |
Ta |
W |
Re |
Os |
Ir |
Pt |
Au |
Hg |
Tl |
Pb |
Bi |
Po |
At |
Rn |
Fr |
Ra |
Ac |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Ce |
Pr |
Nd |
Pm |
Sm |
Eu |
Gd |
Tb |
Dy |
Ho |
Er |
Tm |
Yb |
Lu |
Th |
Pa |
U |
Np |
Pu |
Am |
Cm |
Bk |
Cf |
Es |
Fm |
Md |
No |
Lr |
22
363 |
22 |
22.1 · What Constitutes “Low” Beam Energy X-Ray Microanalysis?
. Fig. 22.6 Periodic table illustrating X-ray shell choices for developing analysis strategy within the low beam energy range, E0 = 2.5 keV (Newbury and Ritchie, 2016)
|
|
|
Elemental measurement strategy for low beam energy analysis |
|
|
|
|
|
|
|
||||||||||||
E0 = 2.5 keV |
|
|
|
|
|
|
|
|
|
Principal shell used for identification |
||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
K-shell |
|
|
|
|
K-L |
|||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|||||||
U0 > 1.25 (Ec < 2.0 keV) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
||||||||
EDS resolution: 129 eV (FWHM, MnKα) |
|
|
|
|
|
|
|
L-shell |
|
|
|
|
L-M |
|||||||||
|
|
|
|
|
|
|
|
|
|
|
||||||||||||
|
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|||||
|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|||
|
|
|
|
Not detectable |
|
|
|
|
|
|
|
M-shell |
|
|
|
|
|
|
||||
|
|
|
|
|
|
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|
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|
|
|
|
|
|
|
|
||||||
H |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
He |
||||||
|
|
|
Marginally detectable: |
|
|
|
|
|
|
|
|
|
|
|
|
|
||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|||||
Li |
Be |
|
|
|
|
|
B |
C |
|
N |
O |
F |
|
Ne |
||||||||
|
|
|
|
|
|
|
||||||||||||||||
|
|
1 < U0 ≤ 1.25 or weak emission |
|
|
|
|
||||||||||||||||
Na |
Mg |
|
|
|
|
Al |
Si |
|
P |
S |
Cl |
|
Ar |
|||||||||
|
|
|
|
|
|
|||||||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|||||||||||
K |
Ca |
Sc |
Ti |
V |
Cr |
Mn |
Fe |
Co |
Ni |
Cu |
Zn |
Ga |
Ge |
|
As |
Se |
Br |
|
Kr |
|||
Rb |
Sr |
Y |
Zr |
Nb |
Mo |
Tc |
Ru |
Rh |
Pd |
Ag |
Cd |
In |
Sn |
|
Sb |
Te |
I |
|
Xe |
|||
Cs |
Ba |
La |
Hf |
Ta |
W |
Re |
Os |
Ir |
Pt |
Au |
Hg |
Tl |
Pb |
|
Bi |
Po |
At |
|
Rn |
|||
Fr |
Ra |
Ac |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Ce |
Pr |
Nd |
Pm |
Sm |
Eu |
Gd |
Tb |
Dy |
Ho |
|
Er |
Tm |
Yb |
|
Lu |
|||
|
|
|
|
Th |
Pa |
U |
Np |
Pu |
Am |
Cm |
Bk |
Cf |
Es |
|
Fm |
Md |
No |
|
Lr |
|||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
. Fig. 22.7 Periodic table illustrating X-ray shell choices for developing analysis strategy within the low beam energy range, E0 = 2.0 keV (Newbury and Ritchie, 2016)
|
|
|
Elemental measurement strategy for low beam energy analysis |
|
|
|
|
|
|
||||||||||||
E0 = 2.0 keV |
|
|
|
|
|
|
|
|
|
Principal shell used for identification |
|||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
K-shell |
|
|
|
|
K-L |
||||
U0 > 1.25 (Ec < 1.6 keV) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|||||||
EDS resolution: 129 eV (FWHM, MnKα) |
|
|
|
|
|
|
|
L-shell |
|
|
|
|
L-M |
||||||||
|
|
|
|
|
|
|
|
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|
|
|||||||||||
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||||
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|
|
|
|
|
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|
|
|
|
|
|
|
|
|
|||
|
|
|
|
Not detectable |
|
|
|
|
|
|
|
M-shell |
|
|
|
|
|
||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
||||||
H |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
He |
||||||
|
|
|
Marginally detectable: |
|
|
|
|
|
|
|
|
|
|
|
|
||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|||||
Li |
Be |
|
|
|
|
|
B |
C |
|
N |
O |
F |
Ne |
||||||||
|
|
|
|
|
|
||||||||||||||||
|
|
1 < U0 ≤ 1.25 or weak emission |
|
|
|
||||||||||||||||
Na |
Mg |
|
|
|
|
Al |
Si |
|
P |
S |
Cl |
Ar |
|||||||||
|
|
|
|
|
|||||||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|||||||||||
K |
Ca |
Sc |
Ti |
V |
Cr |
Mn |
Fe |
Co |
Ni |
Cu |
Zn |
Ga |
Ge |
|
As |
Se |
Br |
Kr |
|||
Rb |
Sr |
Y |
Zr |
Nb |
Mo |
Tc |
Ru |
Rh |
Pd |
Ag |
Cd |
In |
Sn |
|
Sb |
Te |
I |
Xe |
|||
Cs |
Ba |
La |
Hf |
Ta |
W |
Re |
Os |
Ir |
Pt |
Au |
Hg |
Tl |
Pb |
|
Bi |
Po |
At |
Rn |
|||
Fr |
Ra |
Ac |
|
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|
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|
|
|
|
|
|
|
Ce |
Pr |
Nd |
Pm |
Sm |
Eu |
Gd |
Tb |
Dy |
Ho |
|
Er |
Tm |
Yb |
Lu |
|||
|
|
|
|
Th |
Pa |
U |
Np |
Pu |
Am |
Cm |
Bk |
Cf |
Es |
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Fm |
Md |
No |
Lr |
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