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6 Surface and Microanalysis Science Division SUMMARY The mission of the Surface and Microanalysis Science Division (SMSD) is to serve the nation in areas of chemical metrology, research, standards, and the acquisition and analysis of data. The SMSD provides excellent service to the U.S. government and the United Nations through the identification of radioactive and explosive materials as well as the setting of sample standards and development of analytical methods. SMSD research includes a wide range of topics that are critical to the maintenance of national standards and measurement science for the nation. The division is well supported with respect to equipment, facilities, and budget. Supported by both core NIST funding and other agency funding, the division maintains an appropriate balance between the goals of making progress on longer-term problems not amenable to quick solutions and producing results in current areas of interests that enhance the profile of NIST. The morale of the SMSD staff is positive. The researchers are dedicated to the goals mentioned above. This division is an important national resource. RESPONSE TO RECOMMENDATIONS FROM THE PREVIOUS REPORT In the panel’s 2007 report,1 a few minor suggestions were given for further improving the existing high-quality projects of the SMSD. These included better theoretical support for projects involved in the detection of explosive materials, better definition and evaluation of the health and safety risks of nanoparticles, improved theoretical understanding of cluster secondary ion mass spectrometry (SIMS) of organic layers, more extensive collaborations in the clean-room facility with experts on the synthesis and theory regarding the fabrication of molecular electronics, and maintenance of the highly valuable data concerning surface electron microscopy. The majority of the suggestions have been accepted and implemented by the division. For example, a detailed study that involves the preparation and quantitative analysis of standard explosive samples was done. The fundamental properties of explosive molecules have also become better understood since the 2007 review. The transport of nanoparticles in biocells has been delineated. Sputter SIMS analysis of biomaterials was carried out. A semitheoretical study of the organic thin-film transistors fabricated by a device group in another NIST division has been completed. The highly popular x-ray-analysis database that was based on the Apple computer system has been updated to a personal computer system. Additional work on theory, modeling, and simulation should be done, perhaps in collaboration with experts in other divisions of NIST. 1 National Research Council, An Assessment of the National Institute of Standards and Technology Chemical Science and Technology Laboratory: Fiscal Year 2007. Washington, D.C.: The National Academies Press, 2007. 33

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TECHNICAL MERIT The two major objectives of the Surface and Microanalysis Science Division are the development of metrology technology and fundamental scientific research. For the former, five representative topics were demonstrated to the panel. These are as follows: the identification of uranium (U) isotopes, the detection of trace amounts of explosive materials, chemical mapping by desorption mass spectrometry, the tracking and removal of nanoparticles in aquatic environments, and the correlation of cracks in concrete with chemical mapping by high-resolution transmission electron microscopy (TEM). For the latter, three representative topics were shown: chemical imaging of individual nanostructures, mechanisms of charge transfer in molecular nanoelectronics, and super-resolution leading to significantly improved optical microscopy. The division’s scientific program appears to be larger than that for technology development simply because the scientific projects have more subtopics. However, the technical studies are well targeted at solving problems in national and international security, environmental protection and sustainability, and transportation infrastructure. All of these are national priorities with high impact and high visibility. The scientific studies are spread over a wide range of fields in chemistry, bioscience, optics, electronics, materials, and nanotechnology. The accurate identification of trace isotopes of U is unique and critical to DHS and International Atomic Energy Agency (IAEA) missions. The development of trace-detection metrology for explosives is important to national security. For this purpose, a detailed method for the preparation of standard samples has been investigated. The need now is to establish expected sample lifetimes. The integration of chemical analysis techniques would also be beneficial. The work on high-throughput, site-specific chemical mapping by SIMS is of practical value to airport security. The reliability of the process and the long-term effects on health may need investigation. The quantitative chemical imaging of individual nanostructures by TEM is interesting and potentially important for applications to both safety and the environment. It may also have benefit for potential applications to microelectronic devices—for example, in helping to understand Si/high-k-dielectric interfaces. The focus on the development of robust methods of analysis and energy-dispersive techniques for aberration-corrected TEM (in contrast to efforts in electron-energy-loss spectroscopy in other national laboratories) is consistent with the NIST mission of metrology development. The project on studying engineered nanoparticles in aquatic environments is potentially important for water purification. An effective agent, such as a chelator, may help in separating carbon nanotubes from the aquatic environment. The cadmium selenide (CdSe) quantum-dot project, measuring the trophic transfer of nanoparticles in a simplified invertebrate food web, indicates that the biomagnification of nanoparticles, or at least particular types of nanoparticles, may not represent a health hazard. A further study on why the nanoparticles do not accumulate will enhance the visibility of this project. The fast TEM imaging on the formation of cracks in concrete is very good work with practical value. A detailed analysis of the connection between the chemical distribution and crack formation would be an excellent scientific study. More generally, by addressing the analysis of large specimens and connecting micro and macro properties of complex materials, 34

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this work can have a broad impact on detailed characterization and its relationship to the performance properties of a wide variety of complex materials. The work on charge-transfer mechanisms and the probing of surface potentials in nanoelectronics is interesting. The emphasis on developing reliable methods and databases for molecular electronics is appropriate in view of the NIST mission. When completed, the project involving super-resolution optical microscopy will have particularly high impact. The principal investigator has already published several excellent papers on this subject. The overall technical quality of the division is very good, with many projects being among the best. However, the impact of SMSD’s work could be enhanced significantly without the need for major additional resources by adding theoretical support to some of the experimental projects. This could be accomplished, for example, by initiating collaborations with outside organizations. It is encouraging that many of the research projects already involve other divisions in NIST; external government agencies such as the U.S. Air Force, Department of Homeland Security, National Institutes of Health, National Cancer Institute, Food and Drug Administration, Savannah River National Laboratory, and various Army laboratories; industry, including General Electric and SEMATECH; and universities such as the University of Maryland, Pennsylvania State University, and the University of Kentucky. Given the present imbalance between the number of technical staff and the relatively large amount of state-of-the-art equipment, the impact of the division could be made even more impressive by establishing more collaboration with outside organizations such as universities or national laboratories. It can also be anticipated that such collaborations would bring in fresh ideas, and the existing excellent infrastructure would be used to explore new territory. A division-wide strategy needs to be developed to enhance the visibility of the SMSD and its impact in the government and scientific communities, because this division includes a wide range of activities. Some projects can benefit from an improved definition of strategy, such as the long-term direction of scientific study and technology development. The division should also promote worthy investigators for external recognition in the form of prizes and awards. The scientific staff of the division is highly productive. For example, in fiscal year (FY) 2008, division researchers produced 55 manuscripts for publication, made 118 presentations that included 53 invited talks, filed for 1 patent, received 3 awards including 1 fellowship, and participated on 110 committees, including serving as committee leaders. Every member of the scientific staff is involved in the publication and presentation process, with a few members compiling outstanding records. On average, each member of the scientific staff published 1.7 papers and delivered 3.5 talks. This is an excellent record, which shows that the division is meeting its mandate to make a difference in scientific and technical areas. INFRASTRUCTURE AND SUPPORT Compared with most university and industrial research laboratories, the Surface and Microanalysis Science Division has some outstanding experimental equipment. Most of it can be considered top of the line. Laboratory space, utilities, and safety features are all significantly better than what is found in many other laboratories. Although the equipment may not be used to full capacity, as noted above, the scientific and supporting staff engaged in 35

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the research and service programs are outstanding. The use of additional graduate and undergraduate students in the summer is also a positive strategy whose continuation is encouraged. The $12.5 million budget of the division, averaging out to $367,000 per staff member, not including other agency equipment funds, is as good as, or even better than, that found in first-class high-technology companies. The major portion of the budget is for scientific and technical research activities for NIST and other agencies of the U.S. government, showing the scientific importance of the division’s work. About one-third of the portfolio is dedicated to programs related to public safety, security, and standards, showing the commitment of the division to one of the most important goals of NIST. Division staff identified no complaints about the lack of personnel, budget, equipment, or space to carry out projects. Therefore, this is a well-supported division with no obvious deficiencies in infrastructure. OBJECTIVES AND IMPACT The general goal of the SMSD is to serve the nation in areas of chemical metrology, research, standards, and data. The specific goals are to characterize the spatial and temporal distribution of chemical species and to improve the accuracy, precision, sensitivity, selectivity, and applicability of surface, interface, microanalysis, and advanced isotope- measurement techniques. The division carries various activities in order to accomplish these goals satisfactorily. Its work in chemistry metrology includes the detection of trace narcotics, the development of drug-delivery systems, the determination of molecular-orbital structure, and the electronic structure of organic electronics. Its research activities include the adsorption of self-assembled monolayers of nonspecific proteins, spectrometry using supercontinuum sources, the imaging of surface potentials of organic thin-film transistors, the transfer of quantum dots in an invertebrate food web, and super-resolution optical microscopy. Its work in standards development includes the preparation of polymer microspheres containing explosives, precision measurements of isotope ratios, and chemical mapping. Its data activities include reinvention of the Desk Top Spectrum Analyzer and the x-ray spectral imaging of cracks in bridges. This work has demonstrated that the objectives of the division are being fulfilled successfully owing to the effort of its dedicated staff and the availability of the state-of-the-art equipment. The results can be anticipated to have major impacts on national security, the overall mission of NIST, and the scientific community. CONCLUSIONS The Surface and Microanalysis Science Division has successfully accomplished its own targets as well as those of NIST in serving the nation in areas of chemical metrology, research, standards, and data. Many of the scientific studies of the SMSD have achieved excellent results that have, for example, enhanced the capability to characterize surfaces and interfaces with increased accuracy and precision. The division has a competent technical staff with state-of-the-art equipment, advanced facilities, and sufficient budget. To further enhance the capability of the division to achieve its objectives and have more impact on the scientific community, those involved may wish to consider ways of expanding the division’s collaborations with universities and national laboratories so as to make better use of its 36

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facilities and bring in fresh ideas as well as initiate explorations in new areas. Another path to improving the division’s effectiveness is to bring in more theoretical experts, both within NIST and externally, for more in-depth interpretation of some of SMSD’s excellent experimental data. A further area of possible improvement for some projects is a better definition of strategy, such as the long-term direction of scientific study and technology development. Since this division includes a wide range of activities, the development of a division-wide strategy could lead to greatly enhanced visibility and impact in the government and scientific communities. 37