What can electrons do

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What can electrons do?

• Jian-Guo Zheng
• Materials Science Engineering
• EPIC/NUANCE Center
• Northwestern University
• 2220 Campus Drive, 1156 Cook Hall
• Evanston, IL 60208-3108, USA
• Phone [phone], Fax [phone]
• E-mail j-zheng3_at_northwestern.edu

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What can electrons do?
outline

• I. Introduction
• II. Electron microscopy TEM and SEM
• III. Seeing with electrons imaging
• IV. More than images
• V. Challenges and opportunities

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IV. More than images

• SEM EDS, EBSD
• TEM EDS, EFTEM, electron diffraction, EELS,
  STEM, electron holography, cryo-TEM, Tomography,
  in-situ TEM

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IV. More than images

• Elemental maps EDS with SEM
• Elemental maps EDX with STEM
• Elemental Maps Energy-filtered TEM
• Electron Backscatter Diffraction (EBSD) in SEM
• Structure and Orientation SAED
• Structure and defects Nano-Diffraction
• Single atom detection EELS
• Local Electronic Structure EELS
• Electron Holography
• 3-D Tomography with (S)TEM
• Ribosome structure cryo-TEM plus tomography
• Electrical conductance In-situ TEM

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Elemental maps EDS with SEM
10 µm
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Elemental maps EDX with STEM
GMR sample
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Elemental Maps Energy-filtered TEM
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Fe(B) particles
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Electron Backscatter Diffraction (EBSD) in SEM
-Phase identification, texture, grain size,
deformation
High resolution EBSD pattern from as-cast niobium
sample
Scheme for the formation of Kikuchi bands by
diffraction of electrons from a point source in
side of the crystal
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Diffraction
Structure and Orientation SAED
Semiconductor Multi-layers
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Structure and defects Nano-Diffraction
Nano-beam diffraction
Ag nanoprisms
Ag nanoprisms without defects
Tnickness map and profile
Ag nanoprisms with defects
Science, 294(2001), 1901
392-393
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Single atom detection EELS
Single La atoms inside CaTiO3
EELS
HAADF Z-contrast
Phys. Rev. Lett. 92, 955021 (Mar 2004)
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Local Electronic Structure EELS
Z-contrast image
Localized Holes
O-edge
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Electron Holography
Magnetic field
P/N-Doping!
Potential map of pFET device
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3-D Tomography with (S)TEM
-Imaging under variation in specimen
tilt -Capture elemental-/density-/orientation
images -Reconstruct 3D from series of projected
2D images
TEM image set of Quantum dots
3D image
Arslen et al, Science, v309, p2195-2198
Courtesy of Dr. A Twitchett
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Ribosome structure Cryo-TEM plus tomography
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Electrical conductance In-situ TEM
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