Introduction to Nanotechnology

Introduction to Nanotechnology March 10, 2007 bnl manchester Introduction to Nanotechnology March 10, 2007 Some things we will discuss: • How big are nanostructures Scaling down to the nanoscale • How are nanostructures made? Fabrication, synthesis, manufacturing • How do we see them? Imaging and property characterization • Why do we care? Applications to science, technology and society Why do we want to make things small? • To make products smaller, cheaper, faster and better by "scaling" them down. (Electronics, catalysts, water purification, solar cells, coatings, life-science, etc) • To introduce new physical phenomena for science and technology. (Quantum behavior and other effects.) 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 x 10-9 m nano.gov How small are nanostructures? Single Hair Width = 0.1 mm = 100 micrometers = 100,000 nanometers ! 1 nanometer = one billionth (10-9) meter Smaller still Hair 6,000 nanometers DNA . Red blood cell 3 nanometers An Early Nanotechnologist? 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.... ... the Oil tho' not more than a Tea Spoonful ... ... perhaps half an Acre CHALLENGE: How thick was the film of oil? Volume = (Area)(Thickness) V=At It can be determined that the thickness is around 1 nanometer —> ACTIVITY with Oleic Acid A monolayer film (single layer of molecules) Langmuir film ~1 nm thick An Early Nanotechnologist! Langmuir Film of an amphiphilic molecule hydrophobic end e.g., steric acid pressure monolayer film water hydrophilic end QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture. Langmuir-Blodgett Film Must control movable barrier to keep constant pressure multiple dips multiple layers "Optical Lever" laser pointer To determine amplification factor, use the concept of similar triangles "Optical Lever" x2 x1 y1 y2 y 2 y1  x 2 x1 x2 y 2  y1 x1 For example, if the laser pointer is 2" long, and the wall is 17' (204") away,  204 y2  y1 100y1 2 Motion amplified by 100 times! "Optical Lever" for Profilometry laser cantilever . "Optical Lever" for Profilometry laser Long light path and a short cantilever gives large amplification cantilever . Scanning probe microscope Laser Beam Vibrating Cantilever AFM image Surface PS/PEO (large ) µm AFM, STM, MFM, others AFM Cantilever Chip AFM Instrument Head Quicktime Laser Beam Path Cantilever Deflection More on Nanotechnology From DOE 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 14 nm nanowires 13 nm rings 25 nm honeycomb "Nano" • Nanoscale - at the 1-100 nm scale, roughly • Nanostructure - an object that has nanoscale features • Nanoscience - the behavior and properties of nanostructures • Nanotechnology - the techniques for making and characterizing nanostructures and putting them to use • Nanomanufacturing - methods for producing nanostructures in reliable and commercially viable ways Nanotechnology R&D is interdisciplinary and impacts many industries • • • • • • • • • • Physics Chemistry Biology Materials Science Polymer Science Electrical Engineering Chemical Engineering Mechanical Engineering Medicine And others • Electronics • Materials • Health/Biotech • Chemical • Environmental • Energy • Aerospace • Automotive • Security • Forest products • And others Making Small Smaller An Example: Electronics-Microprocessors ibm.com Electronics Keeps On Getting Better Moore's "Law": Number of Transistors per Microprocessor Chip intel.com Since the 1980's electronics has been a leading commercial driver for nanotechnology R&D, but other areas (materials, biotech, energy, etc) are of significant and growing importance. Some have been around for a very long time: • Stained glass windows (Venice, Italy) - gold nanoparticles • Photographic film - silver nanoparticles • Tires - carbon black nanoparticles • Catalytic converters - nanoscale coatings of platinum and palladium nano.gov QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture. "Biggest science initiative since the Apollo program" National Nanotechnology Initiative Program Component Areas (2007 Federal Budget) 1.Fundamental Nanoscale Phenomena and Processes 2.Nanomaterials 3.Nanoscale Devices and Systems 4.Instrumentation Research, Metrology and Standards for Nanotechnology 5.Nanomanufacturing 6.Major Research Facilities and Instrumentation Acquisition 7.Societal Dimensions Making Nanostructures: Nanofabrication • Top down versus bottom up methods •Lithography •Deposition •Etching •Machining •Chemical •Self-Assembly Lithography Mark Tuominen (Using a stencil or mask) Making a microscopic mask Example: Electron-Beam Lithography Electron Beam Polymer film Silicon crystal Nanoscopic Mask ! Lithography IBM Copper Wiring On a Computer Chip Patterned Several Times N AN OFABRICATION BY SELF ASSEMBLY One Example: Diblock Copolymers Block “A” PMMA ~10 nm Block “B” PS Scale set by molecular size Ordered Phases 10% A 30% A 50% A 70% A 90% A CORE CON CEPT FOR N AN OFABRICATION Deposition Template (physical or electrochemical) Etching Mask Remove polymer block within cylinders (expose and develop) Nanoporous Membrane Versatile, self-assembling, nanoscale lithographic system D EVELOPMEN T OF N AN OFABRICATION TECHN IQUES FOR PLASMON IC ARRAYS template dots cylinders rings holes How do we see nanostructures? • A light microscope? Helpful, but cannot resolve below 1000 nm • An electron microscope? Has a long history of usefulness at the nanoscale • A scanning probe microscope? A newer tool that has advanced imaging prelim. Television Set TV screen eye electron beam electron source Light ! Scanning Electron Microscope Electron Beam DETECTOR SAMPLE Scanning probe microscope Laser Beam Vibrating Cantilever AFM image Surface PS/PEO (large ) µm AFM, STM, MFM, others STM Image of Nickel Atoms Pushing Atoms Around STM