Nanotechnology

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Nanotechnology

• Understanding and control of matter at dimensions
  of 1 to 100 nanometers
• Ultimate aim design and assemble any structure
  atom by atom - molecular manufacturing

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Courtesy Office of Basic Energy Sciences,Office
of Science, U.S. Department of Energy
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Natural Nanomachines
ATP synthesis protein (courtesy Dr Christoph
von Ballmoos)
DNA polymerase (biology-online.org)
HIV virus inside a cell (University of Buffalo,
SUNY)
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Agriculture our first use of natures
nanomachines
Chloroplasts in the green parts of the plant
convert carbon dioxide in air into complex
carbohydrate molecules rich in chemical energy.
Chlorophyll molecule that gives leaves and
grasses their green color acts as an efficient
catalyst activated by sunlight
(Florida State University)
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By throwing seeds in the ground, our ancestors
invested wealth of energy of the seed for more
wealth at harvest. Investment a way to grow
rich How much are we investing in Nanotechnology
today?
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What we have Scanning Tunneling Microscope
(STM) 1981 Binnig and Rohrer
The STM can obtain images of conductive surfaces
at an atomic scale of 0.2 nm, and also can be
used to manipulate individual atoms, trigger
chemical reactions, or reversibly produce ions by
removing or adding individual electrons from
atoms or molecules.
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STM allows manipulation of individual atoms
(1989)
Xenon atoms spell IBM on a nickel plate (IBM)
Iron atoms spell Atom on copper in Kanji
characters. (IBM)
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What we have Atomic Force Microscope (AFM) 1986,
Binnig, Quate and Gerber
The AFM provides a three-dimensional surface
profile with vertical resolution of 0.1 nm and
allows to manipulate and study individual
molecules including biological macromolecules
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AFM Manipulation of Single Walled Nanotube, 1999
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Scaling down the microprocessor, the molecular
logic gate.
This molecular gate performs addition (Courtesy
Professor A Prasanna de Silva)
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Top Down Approach - NanomachiningNanolithographyT
echniques

• Optical Lithography (Shortest wavelenght - 193nm)
• Electron Beam Lithography
• Extreme Ultra-Violet Lithography (Shortest
  wavelength 13.5nm)
• Ion projection Lithography
• Nano-imprint Lithography
• X-ray Lithography
• Dip-Pen Lithography

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Top Down Approach - Nanomachining
Nano-Imprint Lithography - NIL
Layer of assembled nanostructures transferred to
a wafer (NSF Center for High-Rate
Nanomanufacturing)
Pattern is imprinted into a mold made of
photo-resistant polymer Mold is then used for
thousands of wafers to transfer the pattern
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Bottom Up Approach Self-assembly
Creating novel molecules capable of assembling
themselves into given superstructures is an
important nanomanufacturing technique.
Fullerenes with functional groups attached to
them self-assemble into a 3D structure.