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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 . Courtesy Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy. Natural Nanomachines.
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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
Courtesy Office of Basic Energy Sciences,Office of Science, U.S. Department of Energy
Natural Nanomachines ATP synthesis protein (courtesy Dr Christoph von Ballmoos) DNA polymerase (biology-online.org) HIV virus inside a cell (University of Buffalo, SUNY)
Agriculture – our first use of nature’s 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)
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?
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.
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)
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
Scaling down the microprocessor, the molecular logic gate. This molecular gate performs addition (Courtesy Professor A Prasanna de Silva)
Top Down Approach - NanomachiningNanolithographyTechniques • 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
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
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.