15-398lecture 5©2004 Seth Copen Goldstein1lecture 5 15-398©2004 Seth Copen Goldstein1Microscopy&ManipulationSeth Copen [email protected] Introduction to Nanotechnologylecture 5 15-398©2004 Seth Copen Goldstein2TodayExamining the nanoscaleSEMTEMSTMAFMManipulating atomsSTMAFMlecture 5 15-398©2004 Seth Copen Goldstein3A Bit of Microscopy HistoryTimeOptical Microscope~1700Electrons: TEM1931SEM: 19421981: STM1986: AFMwww.prynearson.com/science.htmhttp://www.trincoll.edu/~alehman/images/Instruments/http://sibener-group.uchicago.edulecture 5 15-398©2004 Seth Copen Goldstein4Transmission MicroscopyLight:Max resolution 275nmElectronsMax resolution <.1nmWhy electrons are better?De Brogliewavelength of e-? h/mvmvis controllable!15-398lecture 5©2004 Seth Copen Goldstein2lecture 5 15-398©2004 Seth Copen Goldstein5Transmission Electron Microscopelecture 5 15-398©2004 Seth Copen Goldstein6TEMResolution: atomicCan determine 3-D structureBe careful of e-- e-interactionslecture 5 15-398©2004 Seth Copen Goldstein7Scanning Electron Microscopelecture 5 15-398©2004 Seth Copen Goldstein8SEMResolution: atomicSurface featuresRequires VacuumOften must coat specimensNASA nanotech group15-398lecture 5©2004 Seth Copen Goldstein3lecture 5 15-398©2004 Seth Copen Goldstein9Comparing imageslecture 5 15-398©2004 Seth Copen Goldstein10Scanning Probe MicrscopesScanning Probe TipSampleWhat might you measure?How might you measure it?lecture 5 15-398©2004 Seth Copen Goldstein11STMlecture 5 15-398©2004 Seth Copen Goldstein12STM cartoonSample-Battery +CurrentTunneling Current15-398lecture 5©2004 Seth Copen Goldstein4lecture 5 15-398©2004 Seth Copen Goldstein13STM modesConstant-current modeMeasure height of probe to keep tunneling current same Constant-height modeMeasure tunneling currentFasterRequires smoother surfaceResolutionXY: 1nm, Z: .1nmlecture 5 15-398©2004 Seth Copen Goldstein14Worlds smallest Billboard?Xenon atomslecture 5 15-398©2004 Seth Copen Goldstein15STM imagesSTM of copper(111)Can you identify:-Spheres?-waves?-Valleys?-Plateaus?lecture 5 15-398©2004 Seth Copen Goldstein16Quantum Corrals15-398lecture 5©2004 Seth Copen Goldstein5lecture 5 15-398©2004 Seth Copen Goldstein171.2nm CNTD. Carroll, Clemson U. lecture 5 15-398©2004 Seth Copen Goldstein18Si(111)1000KJ. Krim, North Carolina State University 28KRHK Tehcnology, Inc.lecture 5 15-398©2004 Seth Copen Goldstein19Atomic Force MicroscopeMicroscope TipSample Surface scanned back and forthMirrorLASERLASER DetectorComputerDisplaylecture 5 15-398©2004 Seth Copen Goldstein20AFM ModesForceTapping ModeContact modeNon-contactTip Sample separationWhat forces act to attract? Repulse?15-398lecture 5©2004 Seth Copen Goldstein6lecture 5 15-398©2004 Seth Copen Goldstein21Contact ModeContact-modeInteraction between tip and sample in physical contactCan damage sample, espbio materialsForces in nanoNewtonsTapping ModeVibrate tip, measure freq of oscillationlecture 5 15-398©2004 Seth Copen Goldstein22Tapping ModeHeightPhase ShiftAmplitudelecture 5 15-398©2004 Seth Copen Goldstein23Different Data -> different viewsfreeze fractured styrene-isobutylene-styrene a-b-a block copolymer film,from: http://www.psrc.usm.edu/mauritz/afm.htmllecture 5 15-398©2004 Seth Copen Goldstein24Made from Si or Si3N415-398lecture 5©2004 Seth Copen Goldstein7lecture 5 15-398©2004 Seth Copen Goldstein25Carbon nanotubeslecture 5 15-398©2004 Seth Copen Goldstein26Interprettingimageslecture 5 15-398©2004 Seth Copen Goldstein27More artifactslecture 5 15-398©2004 Seth Copen Goldstein28Subatomic resolution15-398lecture 5©2004 Seth Copen Goldstein8lecture 5 15-398©2004 Seth Copen Goldstein29AFM ImagesNaClon Mica (5.6nmx4.8nm)HardDisklecture 5 15-398©2004 Seth Copen Goldstein30Dip-Pen LithographyCan Read and Write!lecture 5 15-398©2004 Seth Copen Goldstein31InksSoft MaterialsSmall functional moleculesSAMsConducting polymersBiopolymers / macromolecules Hard MaterialsMetal inksSol precursor inorganic inksNanoparticlecatalystsFrom Nanoincpresentationlecture 5 15-398©2004 Seth Copen Goldstein32Speeding up the process15-398lecture 5©2004 Seth Copen Goldstein9lecture 5 15-398©2004 Seth Copen Goldstein33TodayLooking at (and modifying) the nanoscaleSEM/TEMSTM/AFMFor Thursday: read chapter 3.This document was created with Win2PDF available at http://www.daneprairie.com.The unregistered version of Win2PDF is for evaluation or non-commercial use