An Introduction to Nanotechnology
Terry Bigioni
The Graham School
of General Studies
The University of Chicago
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What is Nanotechnology?
WHAT DOES NANOTECHNOLOGY
MEAN TO YOU ?
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What is Nanotechnology?
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What does “nanotechnology” mean?
What has nanotechnology done?
What can we expect it to do?
Is it an evolution or a revolution?
How will it change industries?
How will it change our lives?
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What is Nanotechnology?
Nanoscience and nanotechnology concerns
objects that are extremely small.
How small?
Bigger than atoms, but smaller than you can
see with a light microscope.
1 → 100 nanometers
(3-4 atoms side by side = 1 nm)
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Just How Big is a Nanometer Anyway?
1Å 1nm
1um
1mm 1cm
1m
10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1 100 m
Dimensions illustrated on a logarithmic scale, in meters. The yellow region is the size
range of interest for nanoscopic physics and chemistry. Red bars are 1 inch and 1 foot.
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Powerful Microscopes
Scanning
Electron
Microscope
(SEM)
CdSe/ZnS Nanocrystal
Cat Flea
Transmission
Electron
Microscope
(TEM)
Fibroblast Cell on Pillars
Sickled hemoglobin in red blood cell
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New Tools of the Trade
metal or semiconductor surface
Scanning Tunneling Microscope
Silicon Atoms
1986 Nobel Prize in Physics: Binnig and Rohrer (1983)
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New Tools of the Trade
30 nm
any kind of surface
Atomic Force Microscope
650 nm
0 nm
Paired Helical Filament
Invented in 1986 by Binnig, Quate and Gerber
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What is Nanotechnology?
Nanotechnology is about:
• Making small objects
• Manipulating small objects
• Creating new materials by varying the size
of the objects
• Building structures from small objects
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What is Nanotechnology?
Nanotechnology is about:
• Making small objects
• Manipulating small objects
• Creating new materials by varying the size
of the objects
• Building structures from small objects
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Why is Small a Big Deal?
What are some advantages of making
things smaller?
• Economic benefits - cost, quantity
• Technologic benefits - speed, power,
integration, practical
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The First “Law” of Small(er)
Intel Corp
The rapid (exponential) rate of miniaturization of semiconductor devices is
unprecedented for any technology or business. ⇒ Intel (2002) ~300M/cm2
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Making Microprocessors is Hard
IBM Research
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Lithography is Imperfect
Lithography can create very complex structures, but they are not
perfect. This leads to inconsistency issues and device failure.
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What Are The Limiting Factors?
(Some) Miniaturization Challenges:
• Cost - the price of technology is also increasing.
• Lithography - finer tools needed to make smaller devices.
• Leaky devices - quantum mechanics cannot be ignored.
• Finite sizes - statistical distributions no longer valid.
• Interconnections - need to connect to the outside world.
Can nanotechnology solve these problems?
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What is Nanotechnology?
Nanotechnology is about:
• Making small objects
• Manipulating small objects
• Creating new materials by varying the size
of the objects
• Building structures from small objects
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Atomic Manipulation
In 1989, Don Eigler arranged these xenon atoms, one by one, on a nickel
surface to spell out the name of his company. (STM)
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Atomic Manipulation
Researchers from UC Irvine recently assembled a chain of gold atoms,
one by one, to study how the properties of gold change with size. (STM)
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Molecular Manipulation
~ 0.7 nm
Researchers from IBM
Zurich pushed individual
molecules across a surface
to form a molecular abacus.
(AFM)
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Molecular Manipulation
Researchers from IBM Zurich also positioned a single carbon
nanotube molecule across a pair of electrical leads. (AFM)
~1nm
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What is Nanotechnology?
Nanotechnology is about:
• Making small objects
• Manipulating small objects
• Creating new materials by varying the
size of the objects
• Building structures from small objects
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Small is… Different!
What happens when materials are made very small?
“Quantum Confinement”
Bawendi et al. (MIT)
“Quantum Conductance”
Salisbury et al. (Georgia Tech)
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Nanocrystals - Quantum Dots
Whetten et al. (Georgia Tech)
Pd145
Au140
The properties of quantum dots depend on their size. As
a result, you can tune the properties by varying the size.
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Nanocrystals - Quantum Dots
The properties of an atom are
determined only by the number
of electrons and protons it has.
The properties of
a quantum dot are
determined by the
many things, e.g.
size, shape, kind
of atoms.
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Nanocrystals - Quantum Dots
Electrons behave like waves.
Electrons on a copper surface
(inside a ring of iron atoms)
behave like the waves in your
coffee cup.
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Nanocrystals - Quantum Dots
Shorter wavelength
Higher energy
Longer wavelength
Lower energy
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Nanotubes - Quantum Conductors
Electrons behave like waves in
nanotubes too. If you can keep
the electrons at only one
wavelength (energy), it is
possible to have no electrical
resistance.
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Magic Numbers - Every Atom Counts!
Equivalent Diameter (nm)
Au~40 -- Au~840
0.1
15
8
1
3
2
1
22
4
5
29 46 93
165
36 69
10
100
1000
Mass (kDa)
Nanocrystals come in certain sizes (“Magic Numbers”).
Thermodynamics determines the size and provides the
driving force for the synthesis of perfect structures.
Whetten et al. (Georgia Tech)
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What is Nanotechnology?
Nanotechnology is about:
• Making small objects
• Manipulating small objects
• Creating new materials by varying the size
of the objects
• Building structures from small objects
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Building Complex Structures
How do you build nanometer-sized objects?
Top Down
(Lithography)
Bottom Up
(Self-Assembly)
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Putting It All Together (with the naked eye)
Whitesides et al. (Harvard)
Macroscopic Self-Assembly!!
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Putting It All Together (from the bottom up!)
Biological
Chemical
Molecular
Self-Assembly!!
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Putting It All Together (beyond molecules)
Array of 5 nm
Au nanocrystals
A new
nanocomposite
material!
Nanoscopic
SelfAssembly!!
Lin et al.
(U Chicago)
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Nanocrystal Array Measurements
Lin et al. (U Chicago)
Combine self-assembly and lithography to
make electrical measurements on this new
nanocomposite material.
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Toward Molecular Devices
Nanosystems Recap!
• Small is different!
• Can measure and move single atoms/molecules.
• Can make “unlimited” numbers of identical
nanometer-sized objects ⇒ building blocks.
• Can tune properties of building blocks.
• Self-assembly gives us organization for free
(bottom-up approach).
• Can combine top-down and bottom-up approaches
to make hybrid technologies.
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Is the Truth Out There?
It is almost dinnertime and your family decides they want to eat a pepperoni pizza.
You tell your kitchen oven computer that you want a pepperoni pizza, then a list of
the ingredients appears on the screen. Perhaps you decide to add mushrooms, so you
type in mushrooms, then hit enter. Ten minutes later, a bell rings, and the oven
computer announces that dinner is ready. You take the hot pepperoni pizza out of
the oven and serve it to your family. Is there anything strange about this scene?
Where did the ingredients for the pizza come from? If scientists studying
nanotechnology are correct, in the near future our food will be created out of atoms
and molecules instead of being cultivated on farms. Once we know the molecular
structure of pepperoni pizza, we can use available atoms and molecules to build a
pizza whenever we want. Nanotechnology is another name for molecular
manufacturing - the science in which things are built one atom or molecule at a time.
Nanotechnology proposes the construction of molecular devices that will have the
ability to manipulate atoms individually and place them exactly where needed to
produce the desired result. Scientists and researchers say this ability is almost here!
http://www.glencoe.com/sec/science/webquest/content/nanotech.shtml