This presentation is based on a booklet produced by FEI Company entitled "An Introduction to Electron Microscopy". The information contained in this presentation is meant as a overview to the art and science of electron microscopy, and can be used by teachers and students alike to learn more about the science of microscopy. You can download the booklet and learn more about the presentation package at http://www.fei.com/resources/student-learning/introduction-to-electron-microscopy/resources.aspx

1. © 2011 FEI Company

2. PART 1:
A BRIEF OVERVIEW
OF MICROSCOPY
• Origins of microscopy
• Historical figures in microscopy
• Three basic classifications of microscopes
• Comparing light microscopy to electron microscopy
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3. History of Microscopy
Human eye cells Paint on concrete Trace elements in quartz
Mikros (small) + Skopeo (look at)
Greek Origin
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4. Historic Figures in Microscopy
Antony van Leeuwenhoek Robert Hooke Ernst Abbe Ernst Ruska Richard Feynman
(1632-1723) (1635-1703) (1840-1905) (1906-1988) (1918-1988)
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5. Basic Microscope Classifications
laser diode
electron source
first condenser lens
multiple segmentphotodiode X, Y piezoelectric
second condenser lens
(position sensitive detector) scanner
condenser aperture mirror
objective condenser lens
microcondenser lens
Scanning
OpticalCharged
(light)
objective aperture
specimen (thin) probe
particle
microscope
selected area objective lens
aperture
light beam
objective imaging piezoelectric
Z lens
scanner microscope
specimen diffraction lens
intermediate lens
first projector lens
light source second projector lens cantilever
Optical (light) microscope
sample Scanning projector chamber
probe microscope Charged particle microscope
(stationary)
(Illustration of a TEM shown) fluorescent screen
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6. Comparing Microscopes
LIGHT MICROSCOPE ELECTRON MICROSCOPE
Electrons are used to “see” –
The source of The ambient light source is
light is replaced by an electron
illumination light for the microscope
gun built into the column
The lens type Glass lenses Electromagnetic lenses
Focal length is charged by
Magnification Magnification is changed by
changing the current through
method moving the lens
the lens coil
Viewing the Fluorescent screen or
Eyepiece (ocular)
sample digital camera
Entire electron path from
Use of vacuum No vacuum gun to camera must be
under vacuum
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7. PART 2:
UNDERSTANDING KEY CONCEPTS
& CORE TECHNOLOGIES
IN MICROSCOPY
• What is resolution and resolving power?
• What is an electron?
• The electron gun
• Electromagnetic lenses
• The importance of vacuum technology
© 2011 FEI Company

8. KEY CONCEPT: Resolution
Resolution
is defined as the act, process, or capability of
distinguishing between two separate, but adjacent
objects or sources of light, or between two nearly
equal wavelengths.
Resolving Power
is the ability to make points or lines which are
closely adjacent in an object distinguishable in
an image.
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9. Resolving Power of the Human Eye
What can we see?
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10. Resolution & Magnification
scale
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11. How is Resolution Affected by Wavelength?
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12. KEY CONCEPT: The Electron
An atom is made up of:
Protons
Neutrons
Electron
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13. CORE TECHNOLOGY: The Electron Gun
• Three main sources
of electrons:
• Tungsten
• LaB6 (lanthanum hexaboride)
• Field Emission Gun (FEG)
• Different costs and
benefits of each
• Each selected primarily
for their brightness
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14. CORE TECHNOLOGY: Electromagnetic Lenses
electron beam
electrical coil
soft iron pole piece
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15. CORE TECHNOLOGY: The Vacuum
• A vacuum is a region
of reduced gas pressure.
• Electron microscopes
use a vacuum to make
electrons behave
like light.
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16. PART 3:
UNDERSTANDING
ADVANCED
MICROSCOPES
• Transmission Electron Microscopes (TEM)
• Scanning Electron Microscopes (SEM)
• Focused Ion Beam Microscopes (FIB)
• FEI DualBeam™ Systems (FIB/SEM)
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17. What is a Transmission Electron Microscope?
electron source
condenser system
specimen (thin)
objective lens
projector lens
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18. TEM Aberration Correction
Spherical Aberration Chromatic Aberration
• Chromatic aberration is distortion that occurs when there is a failure of a lens to
focus all colors (wavelengths) to the same convergence point.
• Correcting the aberration is necessary, otherwise the resulting image would
be blurry and delocalized, a form of aberration where periodic structures
appear to extend beyond their physical boundaries.
• Recent improvements in aberration correction have resulted in significantly-
improved image quality and sample information.
• Spherical aberration occurs when parallel light rays that pass through the central
region of the lens focus farther away than the light rays that pass through the
edges of the lens.
• Result is multiple focal points and a blurred image.
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19. TEM Enables 3D Imaging
3D Imaging
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20. Environmental Microscopy with TEM
Nickel catalyst film on silica membrane
FEI Titan ETEM
Nickel oxide particles in nitrogen gas
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21. What is Scanning Transmission Electron Microscopy?
Elemental map of a 45 nm PMOS
transistor structure
STEM image of a 32nm semiconductor device EDX map of semiconductor device
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22. What is a Scanning Electron Microscope?
electron source
electron beam
impact area
vacuum
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23. Comparing SEM and TEM
TEM SEM
Beam focused to fine point;
Electron Beam Broad, static beams
sample is scanned line by line
Accelerating voltage much lower; not SEM voltage ranges from
Voltages Needed
necessary to penetrate the specimen 60-300,000 volts
Wide range of specimens
Interaction of the
Specimen must be very thin allowed; simplifies
beam electrons
sample preparation
Information needed is
Electrons must pass through and be
Imaging collected near the surface
transmitted by the specimen
of the specimen
Transmitted electrons are collectively Beam is scanned along the
Image Rendering focused by the objective lens and surface of the sample to
magnified to create a real image build up the image
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24. What is a Focused Ion Beam? (FIB)
Platinum Nano-Wire
FIB-cut in steel v2a EE by 1nA to
Cross-section of a semiconductor wafer imagedsteel a plasma FIB
1B milling-002 with
FEI V400ACE Focused Ion Beam
Physical Failure Analysis
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25. What is a DualBeam™ System?
Bidens Ferulifolia Pollen on plant structures
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26. PART 4:
HOW ARE ELECTRON
AND ION MICROSCOPES
USED TODAY?
• Industrial applications
• Life sciences
• Natural resources and energy
• Scientific research
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27. Applications of Microscopy
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28. Industrial Applications
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29. Life Science Applications
Breast cancer cells
Sperm tails tangled up
in a seminiferous tubule
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30. Natural Resources & Energy
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31. Scientific Research
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32. PART 5:
THE FUTURE OF
MICROSCOPY AND
NANOTECHNOLOGY
• Nanotechnology: the future of science
• What is nanotechnology?
• Nanotechnology applications
• Student and teacher resources
© 2011 FEI Company

33. Nanotechnology: The Future of Science is Now
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34. What is Nanotechnology?
na·no·tech·no·lo·gy noun na-nō-tek-nä-lə-jē:
the science of manipulating materials on an atomic or molecular scale
especially to build microscopic devices (as robots)
Electrospun polymethyl methacrylate(PMMA) fibres
Sildenafil Crystals ALU bumps on integrated circuit
Contamination on polymer Polystyrene nanospheres on optical photoresist
Alveoli (glandular secretions)
Artery with red blood cells CuInSe2 Mesentericum Spores mosquito
Tuber thin film
Water mite parasiting on a
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35. Nanotechnology Applications
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36. Student and Teacher Resources
Learn more about FEI, our products, technologies,
and innovations at fei.com
A glossary of useful terms can be found at:
fei.com/resources/glossary-of-terms.aspx
Download or read online the complete “Introduction to
Electron Microscopy” booklet at fei.com/introtoem
© 2011 FEI Company

37. FEI Company
FEI is the world leader in transmission, scanning electron,
and ion beam microscopy. FEI is responsible for numerous
innovations in technology and the integration of electron
and ion optics, fine mechanics, microelectronics,
computer sciences, and vacuum engineering.
FEI is at the forefront of electron
and ion beam microscopy, the
innovation leader since 1935.
Learn more about us
at fei.com
© 2011 FEI Company