Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93...
Transcript of Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93...
![Page 1: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/1.jpg)
EDX Marco Cantoni 1MSE-603 2009
Introduction to EDXEnergy Dispersive X-ray Microanalysis
(EDS, Energy dispersive Spectroscopy)
EDX Marco Cantoni 2MSE-603 2009
Basics of EDX
a) Generation of X-rays
b) DetectionSi(Li) Detector, SDD Detector, EDS (<-> WDS)
c) QuantificationEDX in SEM, Interaction volumeMonte-Carlo-SimulationsEDX in TEM
[ d) EDX in SEM-STEM ]
![Page 2: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/2.jpg)
EDX Marco Cantoni 3MSE-603 2009
Inelastic scattering of electrons at atomsEelectron_in > Eelectron_out
• Continuum X-ray production(Bremsstrahlung, Synchrotron)
•• Continuum XContinuum X--ray ray productionproduction((BremsstrahlungBremsstrahlung, , Synchrotron)Synchrotron)
SE
SE, BSE, EELS
•Inner shell ionization
••Inner shell Inner shell ionizationionization
EDX Marco Cantoni 4MSE-603 2009
Core shell ionisation: chemical microanalysis by X-ray, Auger electrons and Electron Energy Loss
Spectrometries
e-
K
L1 L2L3
KL2L3
Emission Auger
+K
L1 L2L3
Kα2
RX
Emission X
+
K
L1 L2L3
e-
e-
Ionisation
+
Ka1 Ka2 Kb
La1 La2
KL1L2 KL1L3 KL2L3
L1M1M2
M5
M4
M3
M2
M1
L3
L2
L1
K
Rayons X Electrons Auger
1ps
![Page 3: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/3.jpg)
EDX Marco Cantoni 5MSE-603 2009
Emission of characteristic X-ray and Auger electron
EDX Marco Cantoni 6MSE-603 2009
Designation of x-ray emission lines
![Page 4: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/4.jpg)
EDX Marco Cantoni 7MSE-603 2009
EDX Marco Cantoni 8MSE-603 2009
Efficiency of X-ray generationRelative efficiency of X-ray and Auger emission vs. atomic number for K lines
Ionization cross-section vs. overvoltage U=Eo/Eedge
(electron in -> X-ray out)
To ionized the incident electron MUST have an energy larger than the core shell level U>1. To be efficient, it should have about twice the edge energy U>2.
Light element atoms return to fundamental state mainly by Auger emission. For that reason, their K-lines are weak. In addition their low energy makes them easily absorbed.
SEM TEM ->Light elements
Auger Spectroscopy
Heavy elements
EDS
Cu-K 8.1kV, HT 15kVU = 15/8.1 = 1.85
![Page 5: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/5.jpg)
EDX Marco Cantoni 9MSE-603 2009
X-ray production vs. atomic number Z
Low efficiencyfor light
elements!
EDX Marco Cantoni 10MSE-603 2009
Characteristic lines: Moseley's Law
EDS range ~ 0.3-20 keV
To assess an elementall detectables lines
MUST be present!!!
!
known ambiguities:
Al Kα = Br LlS Kα = Mo Ll
![Page 6: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/6.jpg)
EDX Marco Cantoni 11MSE-603 2009
Moseley‘s law for K-series
Frequency ν of X-rays emitted from K-level vs. atomic number
E= hν et λ=c/ν
with the Planck constant:h=6.626 068 76(52) × 10-34 J·sand 1eV = 1.6 10-19 J
( )215 1Z4810.2 −=ν
So, lets measure the X-rays emitted from my sample and determine the composition !
But how to detect it ?
Energy of characteristic XEnergy of characteristic X--rayray--> Element> ElementQualitative EDXQualitative EDX--AnalysisAnalysis
EDX Marco Cantoni 12MSE-603 2009
b) Detection of X-rays (EDX)
![Page 7: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/7.jpg)
EDX Marco Cantoni 13MSE-603 2009
EDX Marco Cantoni 14MSE-603 2009
X-Ray energy conversion to electrical charges:3.8eV / electron-hole pair in averageelectronic noise+ imperfect charge collection:130 eV resolution / Mn Ka line
• Detector acts like a diode: at room temperaturethe leak current for 1000V would be too high !
• The FET produces less noise if cooled !• Li migration at room temperature !• ->Detector cooling by L-N
![Page 8: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/8.jpg)
EDX Marco Cantoni 15MSE-603 2009
Pulse detection and analysis
Pulse detection: Charge ~ energy
Shorter time constant = process time to analyze voltage-> peak broadening (lower energy resolution)
Longer time constant (higher energy resolution)
->pulse rejection (dead time)
EDX Marco Cantoni 16MSE-603 2009
Process timetime constant
Long
low count rate
Higher dead time
narrow peaks
short
high count rate
lower dead time
broad peaks~2’00050
~4’50030
~11’00015
~30’0004
Count rate, cts/sec.
(30% dead time)
Time const.
(μsec.)
resolutionpeak identification
beam currentcount rate
![Page 9: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/9.jpg)
EDX Marco Cantoni 17MSE-603 2009
Detection and artifacts
X-Ray energy conversion to electrical charges:3.8eV / electron-hole pair in averageelectronic noise+ imperfect charge collection:130 eV resolution / Mn Ka line
Take care when looking for “trace” elements (low concentrations). Don’t confuse small peaks with escape peaks !
EDX Marco Cantoni 18MSE-603 2009
Wavelength Dispersive Spectroscopy (WDS)
The specimen, the diffracting crystal and the detector stay on the Rowland circle. To scan the wavelength, this circle rotates around the specimen to satisfyingthe Bragg law
Johansson focusing spectrometer:The diffracting crystal is bent with a curvatureradius double of that of the Rowland circleThe crystal surface is cylindrically ground to the radius of the Rowland circle
![Page 10: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/10.jpg)
EDX Marco Cantoni 19MSE-603 2009
Electron Microprobe EPMA (Electron Probe MicroAnalyser)with WDS
EDX Marco Cantoni 20MSE-603 2009
5-30min.1 min.Acquisition time
1000:1100:1
Peak to background
ratio
difficult++StandardlessAnalysis
difficultEasyUse
≈5eV80-180eVEnergy Resolution
WDSEDS
EDS <-> WDS
![Page 11: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/11.jpg)
EDX Marco Cantoni 21MSE-603 2009
(K,Na)NbO3
Overvoltage,10keV
Continuum,Bremsstrahlung
Electron beam: 10keV Duane-Hunt limit
EDX Marco Cantoni 22MSE-603 2009
Bremstrahlung (background)
• when a charged particle (des-) accelarates or changes direction, it emits an electromagnetic wave.
– This is widely used to produce synchrotron radiation
• On a bulk sample of atomic number Z:• N(E) is the number of photons of energy E, E0 the energy of the incident electron and K the
Kramers constant
( ) ( )E
EEKZEN 0 −
=
![Page 12: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/12.jpg)
EDX Marco Cantoni 23MSE-603 2009
EDS in SEM• Acquisition under best conditions
– Flat surface without contamination(no Au coating, use C instead)
– Sample must be homogenous at the place of analysis (interaction volume !!)
– Horizontal orientation of the surface– High count rate (but dead time below 30%)– Overvoltage U=Eo/Ec >1.5-2
•• For acquisition times of 100sec. :For acquisition times of 100sec. :detection of ~0.5at% for almost all elementsdetection of ~0.5at% for almost all elements
EDX Marco Cantoni 24MSE-603 2009
(K,Na)NbO3
Overvoltage,10keV
Continuum,Bremsstrahlung
Not ideal !
Duane-Hunt limit
![Page 13: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/13.jpg)
EDX Marco Cantoni 25MSE-603 2009
60.4820.368.667.82Min.
61.5121.1310.259.79Max.
100.0061.1420.869.408.60Spectrum 8
100.0060.4920.3710.258.89Spectrum 7
100.0060.8420.639.079.46Spectrum 6
100.0061.0220.779.358.86Spectrum 5
100.0060.4820.369.379.79Spectrum 4
100.0061.5121.139.547.82Spectrum 3
100.0061.0020.758.669.59Spectrum 2
100.0060.9320.7010.188.19Spectrum 1
TotalONbKNaSpectrum
(K,Na)NbO3
EDX Marco Cantoni 26MSE-603 2009
c) Quantification
• First approach:compare X-ray intensity with a standard (sample with known concentration, same beam current of the electron beam)
ci: wt concentration of element i
Ii: X-ray intensity of char. Line
ki: concentration ratio
istdi
istdi
i kI
I
c
c==
Yes, but…..
![Page 14: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/14.jpg)
EDX Marco Cantoni 27MSE-603 2009
Intensity ~ Concentration…?
How manydifferent
samples…?
EDX Marco Cantoni 28MSE-603 2009
![Page 15: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/15.jpg)
EDX Marco Cantoni 29MSE-603 2009
Electron Flight Simulator
EDX Marco Cantoni 30MSE-603 2009
Casino
![Page 16: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/16.jpg)
EDX Marco Cantoni 31MSE-603 2009
EDX Marco Cantoni 32MSE-603 2009
QuantificationWhen the going gets tough…..
[ ] istdi
istdi
i kI
I
c
cFAZ ==××
• "Z" describe how the electron beampenetrates in the sample (Z-dependant and density dependant) and loose energy
• "A" takes in account the absorption of the X-rays photons along the path to samplesurface
• "F" adds some photons when (secondary) fluorescence occurs
Correction matrix
![Page 17: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/17.jpg)
EDX Marco Cantoni 33MSE-603 2009
Flow chart of quantificationMeasure the intensities
and calculate the concentrationswithout ZAF corrections
Calculate the ZAF correctionsand the density of the sample
Calculate the concentrations with the corrections
Is the differencebetween the new and the old
concentrations smaller than the calculation error?
no Yes !stop
EDX Marco Cantoni 34MSE-603 2009
Correction methods:
• ZAF (purely theoretical)
• PROZA Phi-Rho-Z
• PaP (Pouchou and Pichoir)
• XPP (extended Puchou/Pichoir)
• with standards (same HT, current, detector settings)
• Standardless: theoretical calculation of Istd
• Standardless optimized: « hidden » standards, user definedpeak profiles
![Page 18: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/18.jpg)
EDX Marco Cantoni 35MSE-603 2009
Quantitative EDX in SEM• Acquisition under best conditions
– Flat surface without contamination, horizontal orientation of the surface (no Au coating, use C instead)
– Sample must be homogenous at the place of analysis (interaction volume !!)
– High count rate (but dead time below 30%)
– Overvoltage U=Eo/Ec >1.5-2
• For acquisition times of 100sec. :detection of ~0.5at% possible for almost all elements
•• StandardlessStandardless acquisitionacquisition possible with high accuracy (intensities of references under the given conditions can be calculated for a great range of elements), test with samples of known composition, light elements (like O) are critical…
• Spatial resolution depends strongly on HT and the density of the sample
EDX Marco Cantoni 36MSE-603 2009
Demo NSS/INCA
• Peak finding, synthetic spectrum
• Spectrum imaging (extraction of elements)
![Page 19: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/19.jpg)
EDX Marco Cantoni 37MSE-603 2009
Modern EDX systems:
• User friendly interfaces• New and more powerful
electronics (stability of calibrations, higher count rate)
• Drift compensation for long acquisition times (element mapping on CM300 at high mag, “sitelock”)
• Synthesized spectra(spectrum overlay)easier identification
• Advanced element mapping: Spectral imaging (data cube), selection of elements and regions post-acquisition
• Powerfull reporting and Export tools (Word, Powerpoint, html, tifetc.)
EDX Marco Cantoni 38MSE-603 2009
Synthesized spectrum
Spectrum imaging
Data cube
Extraction of element maps
![Page 20: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/20.jpg)
EDX Marco Cantoni 39MSE-603 2009
EDS in TEM
PZT bulk
20nm thick PZTHigh spatial resolution !
EDX Marco Cantoni 40MSE-603 2009
EDS in TEM• Thin samples -> correction
factors weak (A and F can be neglected)
• Very weak beam broadening -> high spatial resolution ~ beam diameter (~nm)
High energy: artifacts !
If only there wasn’t this specimen preparation……
![Page 21: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/21.jpg)
EDX Marco Cantoni 41MSE-603 2009
STEM point analysisSTEM point analysisPbMg1/3Nb2/3O3 (bulk)
Processing option : Oxygen by stoichiometry (Normalised)
Spectrum Mg Si Nb Pb O Total Spectrum 1 30.02 13.32 56.66 100.00 Spectrum 2 19.15 7.96 4.11 11.72 57.06 100.00 Spectrum 3 6.01 12.49 22.13 59.37 100.00 Spectrum 4 5.65 12.39 22.67 59.29 100.00 Spectrum 5 5.63 12.48 22.52 59.36 100.00 Spectrum 6 5.98 13.66 20.11 60.25 100.00 Spectrum 7 5.55 12.45 22.66 59.34 100.00 Spectrum 8 5.49 12.96 21.84 59.72 100.00 Spectrum 9 5.63 12.19 23.04 59.14 100.00 Max. 30.02 13.32 13.66 23.04 60.25 Min. 5.49 7.96 4.11 11.72 56.66
All results in Atomic Percent
EDX Marco Cantoni 42MSE-603 2009
STEM STEM linescanlinescanPb(Zr,Ti)O3 (thick film), slight Pb excess
![Page 22: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/22.jpg)
EDX Marco Cantoni 43MSE-603 2009
STEM Element MappingSTEM Element MappingPMN/PT 90/10 (bulk)
EDX Marco Cantoni 44MSE-603 2009
Artifactshow to recognize/minimize them
![Page 23: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/23.jpg)
EDX Marco Cantoni 45MSE-603 2009
EDSdetector
upper obj. lens polepiece
lower obj. lens polepiece
X-Ray collection in TEM EDS
collimator
sampleholder collection solid angle
EDX Marco Cantoni 46MSE-603 2009
EDSdetector
upper obj. lens polepiece
lower obj. lens polepiece
X-Ray collection in TEM EDS
collimator
sampleholder collection solid angle
![Page 24: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/24.jpg)
EDX Marco Cantoni 47MSE-603 2009
EDSdetector
upper obj. lens polepiece
lower obj. lens polepiece
Stray X-Rays in TEM EDS
collimator
sampleholder collection solid angle
X-rays shower
hole count
EDX Marco Cantoni 48MSE-603 2009
EDSdetector
upper obj. lens polepiece
lower obj. lens polepiece
Stray X-Rays in TEM EDS
collimator
back-scattered e-
to thick sample
![Page 25: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/25.jpg)
EDX Marco Cantoni 49MSE-603 2009
EDSdetector
upper obj. lens polepiece
lower obj. lens polepiece
Stray X-Rays in TEM EDS
collimator
scattered e- to polepieces + thick sample
EDX Marco Cantoni 50MSE-603 2009
EDSdetector
upper obj. lens polepiece
lower obj. lens polepiece
Stray X-Rays in TEM EDS: characteristic x-rays
collimator
![Page 26: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/26.jpg)
EDX Marco Cantoni 51MSE-603 2009
EDSdetector
upper obj. lens polepiece
lower obj. lens polepiece
Stray X-Rays in TEM EDS: continuum (Bremsstrahlung)
collimator
EDX Marco Cantoni 52MSE-603 2009
Ideal samples:
• FIB samples: almost uniform thickness, smallsample size(less bulk material around)
![Page 27: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/27.jpg)
EDX Marco Cantoni 53MSE-603 2009
EDS in TEM
• Thin samples -> correction factors weak (A and F can be neglected), quantification “easy”
• Very weak beam broadening -> high spatial resolution ~ beam diameter (~nm)
• High energy -> artifacts
• Sample preparation, sample geometry……
EDX Marco Cantoni 54MSE-603 2009
Bonus
![Page 28: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/28.jpg)
EDX Marco Cantoni 55MSE-603 2009
SEM
TEMholey Carbon film
KNbO3
Nano-rods
EDX ofPowders
nano particlesSEM or TEM ???
EDX ofEDX ofPowdersPowders
nanonano particlesparticlesSEM or TEM ???SEM or TEM ???
Optical microscopereflected light
EDX Marco Cantoni 56MSE-603 2009
Simulation Electron Flight Simulator EFS
Sample holder
C film
x
x
![Page 29: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/29.jpg)
EDX Marco Cantoni 57MSE-603 2009
SEM 10kVTEM 300kV
x
x
EDX Marco Cantoni 58MSE-603 2009
SEM 10kVSEM-STEM 30kV
x
x
![Page 30: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/30.jpg)
EDX Marco Cantoni 59MSE-603 2009
SEM 10kV STEM 30kV
• Easy interpretation“no” contribution from substrate (C)
• MBTF corrections for quantification
• Interaction volume >> particle size• Sample holder analyzed• No deconvolution possible• Low HT = limited energy range for
ionization energies
EDX Marco Cantoni 60MSE-603 2009
SEM/STEM
TEM sample
BSE-Detector (upside-down)
XL30XL30--SFEGSFEG
Annular dark Annular dark fieldfield
Bright fieldBright field
““Poor manPoor man’’s TEMs TEM””
![Page 31: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/31.jpg)
EDX Marco Cantoni 61MSE-603 2009
SEMSEM--STEM BFSTEM BF SEMSEM--STEM ADFSTEM ADF
KNbO3
EDX Marco Cantoni 62MSE-603 2009
SEM-STEM BF SE detector
![Page 32: Introduction to EDX - CIME | EPFL · Introduction to EDX ... Spectrum 1 8.19 10.18 20.70 60.93 100.00 Spectrum Na K Nb O Total (K,Na)NbO3 MSE-603 2009 EDX Marco Cantoni 26 c) Quantification](https://reader031.fdocuments.in/reader031/viewer/2022020109/5b828f5d7f8b9a2b6f8ed334/html5/thumbnails/32.jpg)
EDX Marco Cantoni 63MSE-603 2009
SEMSEM--STEM ADF 30kV, FIB lamellaSTEM ADF 30kV, FIB lamella
SEMSEM--SE 30kVSE 30kV
EDX Marco Cantoni 64MSE-603 2009
FIBSEM SE of TEM sampleSEM SE of TEM sample
SEM STEM ADF, 30kVSEM STEM ADF, 30kV
“true” STEM, CM300, 300kV. ADF