This PDF file contains the front matter associated with SPIE Proceedings Volume 8036, including the Title Page, Copyright information, Table of Contents, Introduction, and the Conference Committee listing.

The extraordinary throughput of the silicon drift detector energy dispersive x-ray spectrometer (SDD-EDS) enables collection of EDS spectra with much higher integrated counts within practical time periods, e.g., 100 s or less, compared to past experience with the Si(Li)-EDS. Such high count SDD spectra, containing one million to ten million counts, yield characteristic peak intensities with relative standard deviation below 0.25%, a precision similar to that achieved with wavelength dispersive spectrometry (WDS), the "gold standard" of microprobe analysis, but at lower dose because of the greater solid angle of the SDD-EDS. Such high count SDD-EDS spectra also enable more accurate quantification, nearly indistinguishable from WDS for major and minor constituents when the WDS unknown-to-standard intensity ratio ("k-value") protocol is followed. A critical requirement to satisfy this measurement protocol is that the specimen must be a highly polished bulk target. The geometric character of specimens examined in the scanning electron microscope (SEM) often deviates greatly from the ideal flat bulk target but EDS spectra can still be readily obtained and analyzed. The influence of geometric factors such as local inclination and surface topography on the accuracy of quantitative EDS analysis is examined. Normalized concentration values are subject to very large errors, as high as a factor of 10, as a result of deviation of the specimen geometry from the ideal flat bulk target.

Airbags can be encountered in forensic work when investigating a car crash and are typically constructed with primerlike material to begin the deployment apparatus. The mechanisms of airbag deployment can produce particles ideal for scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS) analysis. A recent study published by Berk studied airbags with vents and showed that it is possible for particles generated from the deployment of these airbags to deposit on surfaces in the vehicle as the airbags deflate.¹ Another paper published by Berk reported particles similar in morphology and composition to primer gunshot residue (GSR) are produced by side impact airbags.² This paper's aim will be to show mid-point results of a study still in progress in which non-vented airbags were analyzed to determine if they exhibited the same particle depositing features as their vented airbag counterparts. Further investigation in this study is being performed to find more airbags which produce primer gunshot residue-like particles containing lead, barium, and antimony from airbag deployment. To date, the study has resulted in (1) non-vented airbags exhibiting deposition of particles suitable for SEM/EDS analysis and (2) no gunshot residue-like particles being detected from the airbag residues studied thus far.

Some government agencies take the position that the results of gunshot residue from the hands of victims of shootings are not probative and meaningless. It is my opinion from experience in many cases that this is not the case and the results can mean life or death in some cases. Actual individual cases are described. The results of samples examined years ago with a small number of gunshot residue particles and reexamined recently shows the number and quality of particles that can be located and identified with modern equipment.

The Scientific Working Group on Gunshot Residue (SWGGSR) was founded in 2007. Twenty-four experienced and well-recognized scientists throughout the world are working toward internationally accepted guidelines in the analysis of gunshot residue. With this goal in mind the group has set up specific committees to cogitate and develop recommendations in key areas of gunshot residue analysis. The SWGGSR meets annually and is in constant contact throughout the year via email. In 2007 SWGGSR assumed responsibility for updating ASTM E-1588 the Standard Guide for Gunshot Residue Analysis by Scanning Electron Microscopy/ Energy Dispersive Xray Spectrometry. In 2010 a revised E-1588 was published. The SWGGSR is currently working on a more comprehensive guide that will be published through NIJ (National Institute of Justice) and available for free to everyone in the world. In addition, we have attended meetings hosted by the federal government's SoFs (Subcommittee on Forensic Science) IWG (Interagency Working Groups) to insure our input on the future of forensic science in the Untied States.

Industrial emissions are characteristic of the manufacturing process that produced them. The storage, production and transportation of raw materials, finished product and byproducts create particles that can be characterized using a combination of light and electron microscopy. Complex mixtures of dust that settle on surfaces and individuals inside and outside of a manufacturing facility provide particles that can be compared directly to reference materials from suspected sources. Characterization of settled dusts can also guide an investigation by suggesting potential sources of the particulate comprising the dust.

The methods of optical and electron microscopy and microanalysis are the linchpin of forensic inorganic analysis. However, their capacity is limited as for the exact identification of pigments and colour layers, and therefore it is essential that they be complemented by other methods of phase microanalysis - powder X-ray microdiffraction (micro pXRD) and FTIR in transmission mode. The classic way of sample division for different methods is not suitable with regard to the inhomogeneity of the sequence of strata. That is why a method was tested that would allow performance of optical microscopy, SEM/EDS(WDS), micro pXRD and FTIR in a nondestructive manner, from an identical spot of a single fragment. The solution can be polished sections - embedded samples and microtome sections. Conductive zerobackground single-crystal silicon plates were developed and tested for sample fixation in SEM, micro pXRD and transmission FTIR. Methods using a focused ion beam - FIB have recently gained importance in the field of electron microscopy. In the forensic sphere they can be employed in examinations of metal materials, technical analyses of documents, post-blast and gunshot residues.

Although drift-corrected image acquisition (DCIC) reduces the drift-related blur and distortions significantly, frames may still be slightly suffer from these distortions. When the SCPM frames are taken quickly and frequently, it is possible to compensate for the drift-related displacements of the frame pixels. However, in order to be able to use this technique, it is necessary to find all dead times, e.a. times between acquisitions of two neighboring pixels, lines and frames, when no signal is measured. Dead times can be discovered using variable-frequency modulated light source. Analysis of frames altered by the modulated light of multiple frequencies provides all information needed for calculation of all dead times.

Nanoparticles are often overlooked during routine trace evidence analyses because of their small size and the degree of difficulty needed to efficiently characterize them. However, analytical electron microscopy (AEM) enables the characterization and/or identification of nanoparticles because of its high magnification capability, the ability to gather elemental data and also the ability to determine the internal structure of a single nanoparticles(1). There is a wide variety of natural and manufactured nanoparticles that are prominent within the environment and their presence becomes very valuable in the absence of larger particles. The combustion of materials produces by-products such as nano-sized carbon soot, fumes, fly ash and gun-shot residue (GSR). Using AEM, nano-sized carbon soot, fumes, fly ash and GSR can not only be distinguished from other nanoparticles within the environment but can also be distinguished from each other because of differences in morphology, elemental composition, and internal structure. The elemental information gathered from combustion by-products during AEM analysis can also give an indication of the original source material. Other nanoparticles such as paint pigments and fillers can also be characterized by AEM using morphology, electron diffraction and elemental composition.

We have reported earlier progress in producing polycrystalline wurtzite-polymorph and photo-conductive GaN nanofibers by electrospinning. This paper shows grain stacking during heat treatment and suggests the need to understand nucleation and grain growth following electrospinning. Transmission Electron Microscopy (TEM) analysis of GaN shows brittle fibers, grain stacking, and unfinished grain nucleation. X-Ray Diffraction analysis confirmed dominant hexagonal 101-wurtzite preferential overall orientation and the incipient grains are of high crystalline quality as seen by high resolution TEM.

Electron microscopy was used to study previously sintered nanocomposites featuring dispersed carbon nanotubes by liquid crystal polymer dispersion and further cross-linking into liquid crystal elastomers, which resulted in a thermo-mechanical actuator. The suitability of conventional scanning electron microscopy techniques with varying coating conditions revealed the development of local charging effects, although enough latitude was granted for imaging at high vacuum modes, with differentiating contrast of the filler in the matrix. Carbon coating did contribute to charge management, although the composite might have been thermo-mechanically activated during deposition. Further, effects from focus ion beam thinning and contrast in transmission electron microscopy are discussed.

Two types of tread wear particles are investigated: tread wear particles from a steel brush abrader (TrBP) and particles produced during a steering pad run (TrSP). A leaching experiment in water at pH = 7.5 for 24 and 48h was carried out on TrBP to simulate environmental degradation. Images of all materials were collected by a scanning electron microscope (SEM) together with element microanalytical (EDX) data. Surface morphology is described by a function of wave number (the "enhanced spectrum") obtained from SEM image analysis and non-linear filtering. A surface roughness index, ρ, is derived from the enhanced spectrum. The innovative contribution of this work is the representation of morphology by means of ρ, which, together with EDX data, allows the quantitative characterization of the materials. In particular, the surface roughness of leached TrBP is shown to decay in time and is related to the corresponding microanalytical data for the first time. The morphology of steering pad TrSP, affected by included mineral particles, is shown to be more heterogeneous. Differences in morphology (enhanced spectra and ρ), elemental composition and surface chemistry of TrBP and TrSP are discussed. All methods described and implemented herewith can be immediately applied to other types of tread wear material. The arguments put forward herewith should help in the proper design of those experiments aimed at assessing the impact of tread wear materials on the environment and on human health.

Polyethylene terephthalate-alumina nano-composites from two production processes gave rise to materials H and T, further divided into four and, respectively, three classes of belonging. Electron microscope images of the materials had been visually scored by an expert in terms of an index, β, aimed at assessing filler dispersion and distribution. These properties characterize the nano-composite. Herewith a classification algorithm which includes image spatial differentiation and non-linear filtering interlaced with multivariate statistics is applied to the same images of materials Hand T. The classification algorithm depends on a few parameters, which are automatically determined by maximizing a figure of merit in the supervised training stage. The classifier output is a display on the plane of the first two principal components. By regressing the 1st principal component affinely against β a remarkable agreement is found between automated classification and visual scoring of material H. The regression result for materialT is not significant, because the assigned classes reduce from 3 to 2, both by visual and automated scoring. The output from the non-linear image filter can be related to filler dispersion and distribution.

The helium ion microscope (HIM) probes light elements (e.g. C, N, O, P) with high contrast due to the large variation in secondary electron yield, which minimizes the necessity of specimen staining. A defining characteristic of HIM is its remarkable capability to neutralize charge by the implementation of an electron flood gun, which eliminates the need for coating non-conductive specimens for imaging at high resolution. In addition, the small convergence angle in HeIM offers a large depth of field (~5× FE-SEM), enabling tall structures to be viewed in focus within a single image. Taking advantage of these capabilities, we investigate the interactions of engineered nanoparticles (NPs) at the surface of alveolar type II epithelial cells grown at the airliquid interface (ALI). The increasing use of nanomaterials in a wide range of commercial applications has the potential to increase human exposure to these materials, but the impact of such exposure on human health is still unclear. One of the main routs of exposure is the respiratory tract, where alveolar epithelial cells present a vulnerable target at the interface with ambient air. Since the cellular interactions of NPs govern the cellular response and ultimately determine the impact on human health, our studies will help delineating relationships between particle properties and cellular interactions and response to better evaluate NP toxicity or biocompatibility. The Rutherford backscattered ion (RBI) is a helium ions imaging mode, which backscatters helium ions from every element except hydrogen, with a backscatter yield that depends on the atomic number of the target. Energy-sensitive backscatter analysis is being developed, which when combined with RBI image information, supports elemental identification at helium ion nanometer resolution. This capability will enable distinguishing NPs from cell surface structures with nanometer resolution.

Helium Ion Microscopy has been established as a powerful imaging technique offering unique contrast and high resolution surface information. More recently, the helium ion beam has been used for nanostructuring applications similar to a gallium focused ion beam. A key difference between helium and gallium induced sputtering is the less intense damage cascade which lends this technique to precise and controlled milling of different materials enabling applications. The helium ion beam has been used for drilling 5nm holes in a 100nm gold foil (20:1 aspect ratio) while the gallium beam sputtered holes of a similar aspect ratio seem to be limited to a 50nm hole size. This paper explores the drilling of nanopores in gold films and other materials and offers an explanation for the observed differences in results between helium and gallium ions.

Secondary electron energy distribution (SEED) from Mo, Ni and Pt was measured in helium ion microscope (HeIM) with semispherical retarding potential technique. For all investigated metals the energy position of the SEED maximum and the SEED width in HeIM is found to be noticeably less than in conventional scanning electron microscope and even less than predicted by previous numerical simulations. A simple analytical phenomenological function to describe the SEED shape is suggested. The reasons of the lower energy transfer efficiency in ion-electron interaction are discussed. The impact of the presence of a surface layer on SEED in HeIM is investigated and energy selective images of the specimen with hydrocarbon contaminated region are presented.

We give an overview of the design of a metrological Scanning Probe Microscope (mSPM) currently under development at the National Measurement Institute Australia (NMIA) and report on preliminary results on the implementation of key components. The mSPM is being developed as part of the nanometrology program at NMIA and will provide the link in the traceability chain between dimensional measurements made at the nanometre scale and the realization of the SI metre at NMIA. The instrument is based on a quartz tuning fork (QTF) detector and will provide a measurement volume of 100 μm × 100 μm × 25 μm with a target uncertainty of 1 nm for the position measurement. Characterization results of the nanopositioning stage and the QTF detector are presented along with an outline of the method for tip mounting on the QTFs. Initial imaging results are also presented.

Gratings and step height standards are useful transfer standards for lateral and vertical length scale calibration of AFMs. In order to have traceability to the SI-metre, the standards must have been calibrated prior to use. Metrological AFMs (MAFMs) with online laser interferometric position measurements are versatile instruments for the calibrations. The developed task specific measurement strategies for step height and pitch calibrations with MIKES metrological AFM are described. The strategies were developed to give high accuracy and to reduce the measurement time. Detailed uncertainty estimations for step height and grating pitch calibrations are also given.

In this paper, a method for the calibration of vertical PZT stages using a large range metrological atomic force microscope (LRM-AFM) is described. A vertical PZT stage is mounted onto the system and an optical-flat sample is attached on the top of the PZT stage. The AFM probe working in the contact mode is used as a null indicator which is sensitive to the movement of the optical-flat sample directly driven by the vertical PZT stage. At each state of the PZT stage movement, the AFM probe approaches to the test surface without horizontal scanning in the system. The displacement of the vertical stage is measured by the laser interferometer in LRM-AFM and the corresponding laser interferometer readings and the movements of the PZT stage are recorded. All collected data are retrieved to establish the relationship of the laser interferometer reading versus the PZT stage displacement. The results show that the system is capable of calibrating PZT stage in the range of up to 250 μm with an expanded uncertainty of less than 5 nm.

The National Institute of Standards and Technology (NIST) has a multifaceted program in atomic force microscope (AFM) dimensional metrology. One component of this effort is a custom in-house metrology AFM, called the calibrated AFM (C-AFM). The NIST C-AFM has displacement metrology for all three axes traceable to the 633 nm wavelength of the iodine-stabilized He-Ne laser. A second major component of this program, and the focus of this paper, is the use of critical dimension atomic force microscopy (CD-AFM). CD-AFM is a commercially available AFM technology that uses flared tips and twodimensional surface sensing to scan the sidewalls of near-vertical or even reentrant features. Features of this sort are commonly encountered in semiconductor manufacturing and other nanotechnology industries. NIST has experience in the calibration and characterization of CD-AFM instruments and in the development of uncertainty budgets for typical measurands in semiconductor manufacturing metrology. A third generation CD-AFM was recently installed at NIST. The current performance of this instrument for pitch and height measurements appears to support our relative expanded uncertainty (k = 2) goals in the range of 1.0 × 10^-3 down to 1.0 × 10^-4.

Atomic force microscopy (AFM) can provide a link in the traceability chain between dimensional measurement techniques for nanoparticles, such as dynamic light scattering and differential centrifugal sedimentation, and the realization of the definition of the SI metre. Despite the size of nanoparticles being well within the resolution range of typical AFMs, the accurate measurement of nanoparticles with AFM presents a number of challenges. One of these challenges is the number density of particles deposited on substrates for AFM imaging and measurement. If the number density is too low, it is difficult to obtain adequate measurement statistics, whereas a number density that is too high can result in particle agglomeration on the substrate and make it difficult to image sufficient substrate area to obtain a reliable reference for height measurements. We present imaging and measurement results of 16 nm gold nanoparticles deposited on a substrate functionalized to produce a surface with a number density gradient across the sample. This substrate functionalization shows great potential for achieving reliable and efficient nanoparticle metrology with AFM.

We developed a measurement method for linewidth patterns of photomasks, and started a calibration service of the photomask linewidth measurement. For the photomask standards, high-quality of chromium film patterns, typical thickness of about 80 nm, sharp edges (edge angles more than 85 degree) and smooth side walls on a quart glass substrate were used. Two kinds of microscopes, an atomic force microscope (AFM) and a scanning electron microscope (SEM), were employed to calibrate the linewidth. At the first, the surface profile of line structures were inspected using the AFM, so that the distance between the left and the right side walls at the edge positions were geometrically-determined. Before the each measurement of photomask patterns by the AFM tips, each of the tip shape was checked using a needle artifact. Then AFM profiles of the photomask patterns were corrected using the tip shape data. The linewidth was calculated using the corrected profiles under a definition of the edge positions, a 10 % level from the top film surface. At the next, the linewidth bias between SEM and AFM were evaluated using the AFM data. Using this method, an uncertainty of the linewidth measurement was evaluated at 60 nm for a linewidth range of 0.5 μm-10 μm.

A new 3D-AFM for true 3D measurements of nano structures has been developed at Physikalisch Technische-Bundesanstalt, the national metrology institute of Germany. In its configuration, two piezo actuators are applied to drive the AFM cantilever near its vertical and torsional resonant frequencies. In such a way, the AFM tip can probe the surface with a vertical and/or a lateral oscillation, offering high 3D probing sensitivity. For enhancing measurement flexibility as well as reducing tip wear, a so called "vector approach probing" (VAP) method has been applied. The sample is measured point by point using this method. At each probing point, the tip is approached towards the surface in its normal direction until the desired tip-sample interaction is detected and then immediately withdrawn from the surface. Preliminary experimental results show promising performance of the developed system. The measurement of a line structure of 800 nm height employing a super sharp AFM tip is performed, showing a repeatability of its 3D profiles of better than 1 nm (p-v). A single crystal critical dimension reference material (SCCDRM) having features with almost vertical sidewall is measured using a flared AFM tip. Results show that the feature has averaged left and right sidewall angles of 88.64° and 88.67deg;, respectively. However, the feature width non-uniformity may reach 10 nm within the measurement range of 1 μm. The standard deviation of the averaged middle CD values of 7 repeated measurements reaches 0.35 nm. In addition, an investigation of long term measurement stability is performed on a PTB photomask. The results shows that the 3D-AFM has a drift rate of about 0.00033 nm per line, which confirms the high measurement stability and the very low tip wear.

Through-focus scanning optical microscopy (TSOM) is another 'scanning' based method that provides threedimensional information (i.e. the size, shape and location) about micro- and nanometer-scale structures. TSOM, based on a conventional optical microscope, achieves this by acquiring and analyzing a set of optical images collected at various focus positions going through focus (from above-focus to under-focus). The measurement sensitivity is comparable to what is possible with typical light scatterometry, SEM and AFM. One of the unique characteristics of the TSOM method is its ability to separate different dimensional differences (i.e. ability to distinguish, for example, linewidth difference from line height difference), and hence is expected to reduce measurement uncertainty. TSOM holds the promise of high-throughput, through comparative measurement applications for wide variety of application areas with potentially significant savings and yield improvements.

A large numerical aperture (NA in range 0.65-0.8), diffraction limited, broadband (100 nm - 30,000 nm), all-reflective confocal microscope objective design is discussed. The design is compatible with engineered polarization state of the excitation beam further decreasing focus spot size. Unlike in the other designs in the proposed system measured sample does not obscure final reflector. The proposed objective extends spatial and temporal limits of existing novel optical microscope techniques such as confocal microscopy described, multi-photon microscopy, 4Pi microscopy, I5M microscopy and others. All reflective design gives promise for high power and high resolution laser-machining applications.

Recent nationwide surveys reveal significant decline in students' interest in Math and Sciences. The objective of this project was to inspire young minds in using various techniques involved in Sciences including Scanning Electron Microscopy. We used Scanning Electron Microscope in demonstrating various types of Biological samples. An SEM Tabletop model in the past decade has revolutionized the use of Scanning Electron Microscopes. Using SEM Tabletop model TM 1000 we studied biological specimens of fungal spores, pollen grains, diatoms, plant fibers, dust mites, insect parts and leaf surfaces. We also used fluorescence microscopy to view, to record and analyze various specimens with an Olympus BX40 microscope equipped with FITC and TRITC fluorescent filters, a mercury lamp source, DP-70 digital camera with Image Pro 6.0 software. Micrographs were captured using bright field microscopy, the fluoresceinisothiocyanate (FITC) filter, and the tetramethylrhodamine (TRITC) filter settings at 40X. A high pressure mercury lamp or UV source was used to excite the storage molecules or proteins which exhibited autofluorescence. We used fluorescent microscopy to confirm the localization of sugar beet viruses in plant organs by viewing the vascular bundles in the thin sections of the leaves and other tissues. We worked with the REU summer students on sample preparation and observation on various samples utilizing the SEM. Critical Point Drying (CPD) and metal coating with the sputter coater was followed before observing some cultured specimen and the samples that were soft in textures with high water content. SEM Top allowed investigating the detailed morphological features that can be used for classroom teaching. Undergraduate and graduate researchers studied biological samples of Arthropods, pollen grains and teeth collected from four species of snakes using SEM. This project inspired the research students to pursue their career in higher studies in science and 45% of the undergraduates participated in this project entered Graduate school.

Due to the emerging degree of miniaturization in microstructures, Scanning-Electron-Microscopes (SEM) have become important instruments in the quality assurance of chip manufacturing. With a two- or multiple detector system for secondary electrons, a SEM can be used for the reconstruction of three dimensional surface profiles. Although there are several projects dealing with the reconstruction of three dimensional surfaces using electron microscopes with multiple Everhart-Thornley detectors (ETD), there is no profound knowledge of the behaviour of emitted electrons. Hence, several values, which are used for reconstruction algorithms, such as the photometric method, are only estimates; for instance, the exact collection efficiency of the ETD, which is still unknown. This paper deals with the simulation of electron trajectories in a one-, two- and four-detector system with varying working distances and varying grid currents. For each detector, the collection efficiency is determined by taking the working distance and grid current into account. Based on the gathered information, a new collection grid, which provides a homogenous emission signal for each detector of a multiple detector system, is developed. Finally, the results of the preceding tests are utilized for a reconstruction of a three dimensional surface using the photometric method with a non-lambert intensity distribution.