t’s a hectic early spring day at the Advanced Analysis Facility on the UWM campus. Director Andrei Skliarov is to depart the next day for a trip to his native Russia, and he and researcher Steven Hardcastle are scrambling to identify trace components in a sample brought in by an industrial client. To solve the mystery, Skliarov dashes around a large room, between a scanning electron microscope, a Fourier Transform Infrared spectrometer, a light microscope, and several computer monitors, all the while discussing possibilities in his thick Russian accent, talking half to the client and half to himself. Unlike other facilities in Wisconsin, which focus on specific areas, the AAF houses a broad spectrum of analytical tools, providing the flexibility to answer a wide variety of questions in materials analysis, trace components analysis, and molecular structure analysis.   Deb Generotzky AAF researcher Steven Hardcastle prepares a sample at the ESCA (Electron Spectroscopy for Chemical Analysis) spectrometer. Hardcastle first came to UWM in 1991 as a postdoctoral fellow for former physics professor Brian Tonner. Due to confidentiality agreements with companies they work with, Skliarov and Hardcastle can’t discuss specific details about their industrial projects. One dealt with developing coatings to increase the durability of outdoor signage, which can be challenging. “It’s never one-layer polymer layers,” Skliarov says. “It’s very complex structure: sometimes two, three, five layers that have different properties—optical and electrical properties.” Another example they mention is touchscreen technology, which is seen in industrial and financial applications, as well as video games. “Very tricky technology involved,” Skliarov says. “When you hear what they do, you get amazed.” Prominent area businesses the AAF has worked for include label and signage manufacturer Brady Corporation, engine manufacturer Briggs & Stratton, automotive and facility management control designer Johnson Controls, SC Johnson, Miller Brewing, Aldridge Chemical, Benz Oil, Oshkosh Truck, and many others. Skliarov and Hardcastle generally work in the material sciences—physics, chemistry, materials—but have found themselves exploring other areas as well. “We do not limit ourselves,” Skliarov says. “We’re pushed by other people to use our knowledge in physics and chemistry, physical chemistry, and chemical physics.” “A lot of times,” Hardcastle chimes in, “we ourselves aren’t sure what technique is the best to get answers. So we look at different techniques until we find out specifically how to solve the customer’s problem.” The AAF is also a critical resource for campus researchers. In the past, the facilities have offered internship opportunities for students, and current users include materials professors Carolyn Aita, Tery Barr, Lian Li, and Pradeep Rohatgi; Associate Professor Vladislav Yakovlev and Professor Prasenjit Guptasarma in physics; and professors Dennis Bennett and Wilfred Tysoe in chemistry. AAF materials analysis instruments X-Ray Diffraction Deb Generotzky Hardcastle explains how samples are loaded into the X-ray diffraction spectrometer.   Measures the intensity of an X-ray beam diffracted from materials (mainly solids and films). This a non-destructive technique with minimum sample preparation needed. This technique yields information about the inter-planar atomic distances in the case of crystal materials and atom-atom distances for amorphous solids. The exact crystal phase of the solid can be identified from the measured diffraction peak positions. In addition, glancing angle diffraction scans can study the atomic structure of thin films less than 50 nanometers, and can measure the thickness of thin films. X-ray diffraction can be applied to many science and engineering fields including materials science, metallurgy, physics, chemistry, dentistry, geology, and biology. Electron Spectroscopy for Chemical Analysis (ESCA) or X-Ray Photoelectron Spectroscopy Sample is irradiated with a mono-energetic X-ray beam, causing photoelectrons to be emitted from the sample. An energy analyzer determines the kinetic energy and thus binding energy of the emitted photoelectrons, from which the elemental identity, chemical state, and quantity of an element can be determined. Elemental and chemical information is collected from the top 0.5 to 1.0 nanometer of a surface. Information provided about surface layers or thin film structures is useful in different applications including: polymer modification, catalysis, corrosion, adhesion, semiconductors, electronics packaging, magnetic media, and thin film coatings. Scanning Electron Microscopy (SEM)/Electron Probe (EP)   Peter Hansen Advanced Analysis Facility Director Andrei Skliarov (below) was enlisted by former Graduate School Dean George Keulks to start the AAF in the early 1990s. Keulks envisioned the facility as a cost-effective way to acquire and maintain scientific instrumentation for university-wide use and as a way to promote partnerships with local industries. Many prominent companies enlist the AAF to answer challenging technological questions, and academic researchers from other countries have made use of the facilities. Provides a highly magnified surface image of a sample with good depth perception. Can be used to identify morphology of the samples, surface imperfections, and contaminants down to 10 nanometers or a magnification of 100,000. In addition, the electron probe attachment collects the electron-beam-induced X-rays from the sample. Thus, surface elements and contamination can be measured and identified (for carbon and higher atomic number elements). Elemental information is generally confined to the top 1 to 3 micrometers of the surface of the sample. SEM/EP can be used for such diverse fields as analysis of composite structures and failures, materials composition and uniformity, gun shot residuals, and the thickness of thin films. Gas Chromatography/Mass Spectrometry (GC/MS) Combines the ability of gas chromatography (GC) to separate compounds from a complex mixture with the ability of mass spectroscopy (MS) to identify those compounds, and accurately determine the amounts present. Data is recorded by a computerized system that also analyzes the information obtained and controls the instruments. GC/MS is very sensitive, and can identify samples containing femtogram quantities of compounds. It can analyze a wide range of samples and can be used by entities such as environmental agencies, medical and forensic labs, and the control boards for athletics and horse racing. Fourier Transform Infrared Spectroscopy/FTIR Left: Electron microscopy images of aluminum composite material (grey area) strengthened with graphite fibers (black area) seen in crosssection. The fibers are coated with nickel (white rings around graphite) to increase the adhesiveness of the fibers with the aluminum matrix. From the lab of Professor Pradeep Rohatgi in the Materials Department. Right: The initial method to development new composition superconductors with ever higher transition temperatures is to grind and heat individual compounds until the single desired compound is formed. Here the desired bismuth, strontium, calcium, copper oxide superconductor has not been formed yet. There are obviously at least two distinct compounds present (smooth- and fluffy-looking areas). From the lab of Professor Prasenjit Guptasarma in Physics.   Infrared radiation can be absorbed by the molecular vibrations of a sample. This measured absorption spectrum is used as a “fingerprint” and compared with literally thousands of organic library spectra to identify the compound(s) present. Various attachments have been developed to measure very thin films (down to a few atomic layers) and with microscopic spectroscopy samples and contaminates down to 10 micrometers can be studied. FTIR is primarily used for liquid and solid organic compound identification. It can also be used for gases and, to a limited extent, inorganic compounds. Raman Microscopic Spectroscopy Raman Spectroscopy also measures the molecular vibrations, but uses a different physical property than FTIR. Raman uses a laser (UV to Visible to IR wavelengths are possible) to excite a sample and then measures the shift in wavelengths (very small) as a result. Water does not give a Raman signal, wet samples and suspensions in water can be studied easily. In addition, inorganic samples can be studied with better results than FTIR. The lateral resolution in the case of Laser Raman Microscopy is mainly determined by the optical lenses used and can easily be less than 2 micrometers.