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The Center's research demands state-of-the-art sample surface preparation. Our experiments rely on the ability to prepare very flat, polished surfaces, and to remove very thin sections with a high degree of parallelism. To meet these demands, we have assembled several kinds of polishing, lapping and precision milling instruments. For sectioning of soft metals we have installed a diamond-milling system (Reichert-Jung Polycut E with Ultramiller) capable of the precision removal of ~1 micon layers. A precision spindle polishing machine (Strasbaugh Polishmaster) can be used for mechanical polishing of metal and ceramic samples. We have also acquired a Logitec lapping and polishing system which provides much more rapid polishing action (in comparison with the Strausbaugh polisher) while still maintaining excellent parallelism. Using the Logitec system, we are able to polish samples flat to within ?? 0.5 microns over distances of 1 cm and are able to remove thicknesses as small as 5 microns. The facility also includes optical microscopes, an electropolisher for the finishing of metallic specimens, and an inductively coupled gauge head to determine sample parallelism and the thickness of removed layers. Facilities for the preparation of thin metal film specimens for OIM and TEM studies are maintained in Barmak's laboratory and available for MRSEC research.

The electron microscope facility continues to serve the research and teaching needs of faculty and graduate students in the physical sciences. It operates as a cost center with users from inside the university as well as access to local industry and outside universities. The facility is administered by IMNI with a faculty director (Prof. David Paine), and a full time dedicated research engineer (Anthony McCormick) who maintains the equipment and provides instruction or user assistance on an as-needed basis. The laboratory instrumentation consists of equipment which provides five primary functions:

• (i) Two transmission electron microscopes (JEM 2010-HREM tool and an FEI CM20-analytical tool) for chemical, structural, and crystallographic microstructure analysis,
• (ii) Scanning Electron microscopes (LEO 1530-vp and JEM 845) for microstructural studies of surface relief and morphology and includes crystallographic (EBSD) and chemical (EDS) mapping,
• (iii) a new FEI Helios Dual Beam FIB with an Omniprobe nanomanipulator and autoTEM sample preparation, Nabbity extended lithography package, 3-D EBSD, and accessories for high resolution lithography,
• (iv) Auger/ESCA system VG ESCA Lab II for surface composition, depth profile, and XPS analysis and,
• (v) full sample preparation facilities including optical microscopes, ion mills, and plasma deposition tools. In addition, optical and atomic force microscopes are available in the facility. Funding has been secured for the acquisition of a 200 kV Field Emitter TEM which should be ready for installation by June 2010.

The GRL 231 Characterization Lab has a variety of apparatus for characterizing the optical and electronic properties of materials. These include photoluminescence spectroscopy, thermal deflection spectroscopy, electron spin resonance spectroscopy, fourier transform infrared spectroscopy and spectrophotometry. This lab is shared with the Scales Research Group, which studies terahertz spectroscopy techniques.

This facility consists of a PHI Model 600 scanning Auger microprobe (SAM). Recently, the instrument was upgraded with a modern PC based computer, new controlling electronic modules, and new software that improves our capabilities to acquire, process, and transmit the data. In early 2003, we plan another software upgrade that will increase the number of acquisition points, from 40 to 1000, in the Multiplex mode. This mode allows acquisition of semi-quantitative elemental compositions at specific points on the sample surface. This will be especially useful for our study on GBs segregation, where a wide range of GBs have to be chemically analyzed on fracture surfaces.

Chapel Hill Analytical and Nanofabrication Laboratory (CHANL) houses facilities for materials characterization and a versatile suite of instrumentation for micro and nanofabrication.

The lab provides professional consultation on problems regarding electronics design and operation. It also provides fee-based repair and equipment construction services to MRSEC members. In the recent past, it has designed and constructed specialized circuitry for laser power and timing stabilization, computer interfaces for electron energy spectrometers, and high-frequency quadrature signal demodulators. In addition, the lab maintains a pool of electronic measurement and test equipment that can be signed out by MRSEC members.

Freeze-fracture transmission electron microscopy (FFTEM) is a powerful technique for imaging the nanometer-scale structure of soft condensed matter, revealing features as small as a single smectic liquid crystal layer (~ 3 nm). We use FFTEM to study the bulk and interfacial structure of equilibrium and non-equilibrium states of liquid crystals and nanocolloids.

Analytical techniques available include Auger spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, and several kinds of thermal analysis. A wide array of spectrophotometric techniques, including UV-visible-near IR spectrophotometry, Fourier transform infrared spectroscopy, Raman spectroscopy and fluorimetry are also available.

The Mechanical Testing Facility enables investigators to create novel materials and structures through crystal growth, hot pressing, vacuum casting, diffusion bonding, and cold iso-static pressing. Once created, materials may be shaped by conventional machining, wire EDM, and specialty surfacing equipment. The mechanical properties of the material may be characterized over a wide range of temperatures, atmospheres, loading rates, and testing regimes. The facility is staffed by a senior research engineer and two senior technical assistants.