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Summary of NSF Surface Analysis Workshop. Kettering University, Flint, Michigan 23-27 June 2003. Ronald Kumon Summer 2003. Purposes of Workshop. Provide an overview of a variety of surface analysis techniques and their applications
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Summary of NSF Surface Analysis Workshop Kettering University, Flint, Michigan 23-27 June 2003 Ronald Kumon Summer 2003
Purposes of Workshop • Provide an overview of a variety of surface analysis techniques and their applications • Expose participants to “cutting edge” experimental equipment • Share ideas for hands-on experiments that are primarily suitable for inclusion in an undergraduate curriculum
Schedule • Monday : Overview, facilities tour, optical microscopy • Tuesday : Vibrational spectroscopy (Raman and IR) • Wednesday: Electron spectroscopy (ESEM, ESCA/XPS) • Thursday : Scanning probe microscopy (STM, AFM) • Friday : Conclusion and evaluation
Participants • 9 participants: 6 chemistry, 3 physics • Professors, postdocs, graduate students • Universities, colleges, community colleges Instructors • Prof. Bahram Roughani, Physics • Prof. Diana Phillips, Chemistry • Mr. Robert Cunningham, Lab Coordinator
Information from Surfaces • Elemental composition • Chemical composition • Morphology • Surface homogeneity • Crystalline structure • Elastic properties • Electrical properties
Examples of Applications • Microelectronics • Catalysis • Nanotechnology • Drug Delivery • Fuel Cells • Corrosion • Coatings and Adhesion
Applicable Courses • Modern Physics • Materials Characterization • Physical Chemistry • Polymer Chemistry • Surface Analysis (special topics) • Undergraduate Research • Graduate Research
Experimental Considerations • What do you want to know? • How fast do you need the answer? • How much do you want to spend? • Is the sample vacuum compatible? • Does the sample absorb radiation? • Do you need certain temperatures, pressures, or chemical environment? • How stable is the sample’s surface?
Vibrational Spectroscopy • Infrared (IR) absorption • Provides information about chemical bonding • Done in transmission or reflection • Raman scattering • Provides information about chemical bonding, crystalline structure, etc. • Weaker than dominant Rayleigh scattering
Comparison of Spectra Water vibrations • Spectra are typically complementary
IR Laboratory Example of IR spectrum Thermo Nicolet Avatar 360 FT-IR
Raman Laboratory Side view of Raman spectrometer Sample holder and microscope
Electron Micro-/Spectroscopy • Environmental Scanning Electron Microscopy (ESEM) • Electron Spectroscopy for Chemical Analysis (ESCA), a.k.a., X-ray Photoelectron Spectroscopy (XPS) ESEM ESCA
ESEM Laboratory Sample images Environmental SEM and EDX system
ESCA Laboratory Front view of ESCA system Top view of ESCA system
Scanning Probe Microscopy • Scanning Tunneling Microscopy (STM) • Probability of electron tunneling varies exponentially from tip • Atomic Force Microscopy (AFM) • Sensitive to force between surface and tip • Tip deflection measured by laser beam deflection of cantilever STM AFM
STM Demonstration View of probe tip through magnifier Top view of STM
AFM Demonstration AFM probe tips Pacific Nanotechnology AFM system
Magnetic F.M. with Legos Laser beam deflection changes when arm moves over magnets
Polymer Applications • IR, Raman for uncured adhesive samples • IR, Raman, ESCA, ESEM, AFM for cured adhesive samples • Several samples of uncured and cured epoxy left at Kettering for further analysis • Examples of various techniques shown on the next slides
IR analysis of adhesion Identification of adhesive material
Raman imaging of epoxy Raman image of thin film of rubber-toughened epoxy resin at 1665 cm-1 [Garton et al., Appl. Spectrosc. 47, 922-927 (1993)]
ESCA of adhesion • Painted plastic parts were glued to body of vehicle • Samples with more Si tended to fail more often (from U. W. Ontario Surface Science web site)
AFM Imaging of Polymers LFM Structured polymer (topo+LFM) PCM Block co-polymer (topo+PCM)
Conclusion • Learned about surface analysis techniques • Exposed to ideas for adding surface analysis methods into undergraduate and graduate curriculum • Met other physicists and chemists • Obtained some ideas about potential directions for future research
Acknowledgments • National Science Foundation • Georgia State University • Kettering University • University of Windsor Presentation archived at: http://ron.kumonweb.com/pro/research.html