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Nanotechnology: Past, Present, and Future. STEM ED UMass. March 29, 2008. Introduction to Nanotechnology: What, Why and How. bnl. manchester. UMass Amherst Nanoscale Science and Engineering Center. Nanotechnology: What ?. Nanotechnology.
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Nanotechnology: Past, Present, and Future STEM ED UMass March 29, 2008
Introduction to Nanotechnology: What, Why and How bnl manchester UMass Amherst Nanoscale Science and Engineering Center
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
Single Hair Width = 0.1 mm How small are nanostructures? = 100 micrometers = 100,000 nanometers ! 1 nanometer = one billionth (10-9) meter
DNA 6,000 nanometers Red blood cell 3 nanometers Smaller still Hair .
A Few Nanostructures Made at UMass 100 nm dots 70 nm nanowires 200 nm rings 150 nm holes 18 nm pores 12 nm pores 14 nm dots 13 nm rings 25 nm honeycomb 14 nm nanowires
"Nano" • Nanoscale - at the 1-100 nm scale, roughly • Nanostructure - an object that has nanoscale features • Nanoscience - the properties of nanostructures and the underlying science • Nanotechnology - the techniques for making and characterizing nanostructures and putting them to use • Nanomanufacturing - methods for producing nanostructures in reliable and commercially viable ways
20 GB 40 GB 10 GB 2001 2002 2004 Hard drive Magnetic data storage 80 GB 160 GB 2006 2007 Example: Advancement of the iPod 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
25 DVDs on a disk the size of a quarter, or all Library of Congress books on a 1 sq ft tile! Scaling Down to the Nanoscale Increases the amount of data stored on a fixed amount of “real estate” ! Now ~ 100 billion bits/in2, future target more than 1 trillion bits/in2
Why do we want to make things at the nanoscale? • To make better and new products: smaller, cheaper, faster and more effective. (Electronics, catalysts, water purification, solar cells, coatings, medical diagnostics & therapy, etc) • To introduce completely new physical phenomena to science, technology. (Quantum behavior and other effects.) (More on why later)
Nanotechnology: How? • How to make nanostructures? • How to characterize and test them?
Lithography • Deposition • Etching • Machining • Chemical • Self-Assembly Making Nanostructures: Nanofabrication • Top down versus bottom up methods
Nanostructures nanofilm, or nanolayer (2D) macroscale (3D) object height depth width nanoparticle, nanodot, quantum dot (0D) nanowire, nanorod, or nanocylinder (1D)
An example of a FILM: Oil on water A monolayerNANOFILM (single layer of molecules) ~1 nm thick Langmuir film This is an example of SELF-ASSEMBLY
Nanofilm byThermal 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 must be held low to prevent contamination! vacuum ~10-7 torr source There are many other thin film manufacturing techniques resistive, e-beam, rf or laser heat source vacuum pump
Working Electrode (WE) Counter Electrode (CE) "oxidation" Cu(0) –> Cu2+ + 2e- Nanofilm by Electroplating I V cathode anode CuSO4 dissolved in water If using an inert Pt electrode: 2 H2O –> O2 + 4H+ + 4e- "reduction" Cu2+ + 2e- –> Cu(0)
"Optical Lever" for Profilometry laser . cantilever
"Optical Lever" for Profilometry Long light path and a short cantilever gives large amplification laser . cantilever
AFM Instrument Head AFM Cantilever Chip Atomic Force Microscope Laser Beam Path Cantilever Deflection
STM Image of Nickel Atoms
Lithography Mark Tuominen Mark Tuominen (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
Electron Beam Polymer film Silicon crystal Electron-Beam Lithography Nanoscopic Mask !
Self-Assembled Nanostructuresand Lithography Based on Self-Assembly
Self Assembly
Diatoms sinancanan.net priweb.org
~10 nm NANOFABRICATION BY SELF ASSEMBLY 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
Computer Microprocessor "Heart of the computer" Does the "thinking"
Making Small SmallerAn Example: Electronics-Microprocessors microscale nanoscale macroscale ibm.com
Electronics Keep On Getting Better Moore's "Law": Number of Transistors per Microprocessor Chip intel.com
coil Perpendicular Write Head Granular Media Soft Magnetic UnderLayer (SUL) • CHM Goal: Make "perfect" media using self-assembled nano-templates • Also, making new designs for storage Improving Magnetic Data Storage Technology • The UMass Amherst Center for Hierarchical Manufacturing is working to improve this technology 1 bit Y. Sonobe, et al., JMMM (2006)
Electrodeposited Nanowires in a Nanoporous Polymer Template (Mask) nanowires in a diblock copolymer template nanoporous template 1x1012 wires/in2
Solar Cells Benefit: Sun is an unlimited source of electronic energy. Konarka
“load” + - Electric Solar Cells Made from single-crystal silicon wafers (conventionally) Sunlight wires - cross-sectional view n-type silicon Voltage p-type silicon + Current The load can be a lamp, an electric motor, a CD player, a toaster, etc
“load” Nanostructured Solar Cells Sunlight - Voltage + Current More interface area - More power!
Nanotechnology R&D is interdisciplinary and impacts many applications • Electronics • Materials • Health/Biotech • Chemical • Environmental • Energy • Aerospace • Automotive • Security • Forest products • And others • Physics • Chemistry • Biology • Materials Science • Polymer Science • Electrical Engineering • Chemical Engineering • Mechanical Engineering • Medicine • And others
Re: Your future My Advice to Students: • Pursue your interests • Ask questions • Be clever • Do! Thanks for visiting UMass and learning about nanotechnology!