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Introduction to Nanotechnology: What, Why and How. Mark Tuominen Professor of Physics. Science Saturday, Sept. 12, 2009: Part 1. Nanotechnology. The biggest science initiative since the Apollo program. Nanotechnology.
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Introduction to Nanotechnology: What, Why and How Mark Tuominen Professor of Physics Science Saturday, Sept. 12, 2009: Part 1
Nanotechnology The biggest science initiative since the Apollo program
Nanotechnology Nanotechnology is the understanding and control of matter at dimensions of roughly 1 to 100 nanometers, where unique phenomena enable novel applications. 1 nanometer = 1 billionth of a meter = 1 x 10-9 m nano.gov
Analogy 12,760 km 1.276 cm Change in Scale 1 nanometer = 1/1,000,000,000 of a meter (A MAJOR change in scale) 12,760 km = 1.276 x 104 km = 1,276 x 107 m 1.276 x 107 m / 1 x 109 = 1.276 x 10-2 m = 1.276 cm (one billionth of the earth's diameter)
Single Hair Width = 0.1 mm How small are nanostructures? = 100 micrometers = 100,000 nanometers !
DNA 6,000 nanometers 3 nanometers 10 nm objects made by guided self-assembly Smaller still Hair . 100,000 nanometers
Applications of Nanotechnology
20 GB 40 GB 10 GB 2001 2002 2004 Hard drive Magnetic data storage 80 GB 160 GB 2006 2007 First, An Example: iPod Data Storage Capacity Uses nanotechnology!
“Read” Head Signal 0 0 1 0 1 0 0 1 1 0 _ _ “Bits” of information Magnetic Data Storage A computer hard drive stores your data magnetically “Write” Head current S N Disk N S direction of disk motion
Why do we want to make things at the nanoscale? • To make better products: smaller, cheaper, faster and more effective. (Electronics, catalysts, water purification, solar cells, coatings, medical diagnostics & therapy, and more) • To introduce completely new physical phenomena to science and technology. (Quantum behavior and other effects.) For a sustainable future!
Types of Nanostructures and How They Are Made
Lithography • Deposition • Etching • Machining • Chemical • Self-Assembly Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods
Nanofilms Nanofilm on glass Nanofilm on plastic Au, Cr, Al, Ag, Cu, SiO, others Pressure must be held low to prevent contamination! Gold-coated plastic for insulation purposes "Low-E" windows: a thin metal layer on glass: blocks UV and IR light
Working Electrode (WE) Counter Electrode (CE) "oxidation" Cu(0) –> Cu2+ + 2e- ("electroplating") Nanofilm by Electrodeposition I V cathode anode CuSO4 dissolved in water "reduction" Cu2+ + 2e- –> Cu(0)
A thin film method:Thermal Evaporation sample QCM Vaporization or sublimation of a heated material onto a substrate in a vacuum chamber film vapor Au, Cr, Al, Ag, Cu, SiO, others Pressure is held low to prevent contamination! vacuum ~10-7 torr source There are many other thin film manufacturing techniques heating source vacuum pump
Lithography Nanoscience Rocks! Nanoscience Rocks (Using a stencil or mask)
spin coating apply spin bake spin on resist resist expose unexposed exposed mask (reticle) "scission" develop deposit liftoff narrow line process recipe substrate Photolithography for Deposition
Lithography Patterned Several Times IBM Copper Wiring On a Computer Chip
Computer Microprocessor "Heart of the computer" Does the "thinking"
Making Small SmallerAn Example: Electronics-Microprocessors microscale nanoscale macroscale ibm.com
Self Assembly
Excerpt from Letter of Benjamin Franklin to William Brownrigg (Nov. 7, 1773) ...At length being at Clapham, where there is, on the Common, a large Pond ... I fetched out a Cruet of Oil, and dropt a little of it on the Water. I saw it spread itself with surprising Swiftness upon the Surface ... the Oil tho' not more than a Tea Spoonful ... which spread amazingly, and extended itself gradually till it reached the Lee Side, making all that Quarter of the Pond, perhaps half an Acre, as smooth as a Looking Glass.... A nanofilm!
"Quantum Dots" by Chemical Synthesis (reverse-micelle method) "Synthesis and Characterization of Nearly Monodisperse Semiconductor Nanocrystallites," C. Murray, D. Norris, and M. Bawendi, J. Am. Chem. Soc. 115, 8706 (1993)
~10 nm SELF ASSEMBLY with DIBLOCK COPOLYMERS Block “B” Block “A” PS PMMA Scale set by molecular size Ordered Phases 10% A 30% A 50% A 70% A 90% A
Deposition Template Etching Mask Nanoporous Membrane CORE CONCEPT FOR NANOFABRICATION (physical or electrochemical) Remove polymer block within cylinders (expose and develop) Versatile, self-assembling, nanoscale lithographic system
Nanomagnets in a Self-Assembled Polymer Mask nanoporous template 1x1012 magnets/in2 Data Storage... ...and More