This PDF file contains the front matter associated with SPIE Proceedings Volume 7729, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

Scanning electron microscopy is a useful tool for understanding food contamination and directing product development of food and industrial products. The current trend in food research is to produce foods that are fast to prepare and/or ready to eat. At the same time, these processed foods must be safe, high quality and maintain all or most of the nutritional value of the original whole foods. Minimally processed foods, is the phrase used to characterize these "new" foods. New techniques are needed which take advantage of minimal processing or processing which enhances the fresh properties and characteristics of whole foods while spending less time on food preparation. The added benefit coupled to less cooking time in an individual kitchen translates to an overall energy savings and reduces the carbon emissions to the environment. Food processing changes the microstructure, and therefore, the quality, texture and flavor, of the resulting food product. Additionally, there is the need to reduce waste, transportation costs and product loss during transportation and storage. Unlike food processing, structural changes are desirable in co-products as function follows form for food packaging films and boxes as well as for building materials and other industrial products. Thus, the standard materials testing procedures are coupled with SEM to provide direction in the development of products from agricultural residues or what would otherwise be considered waste materials. The use of agricultural residues reduces waste and adds value to a currently underutilized or unutilized product. The product might be biodegradable or compostable, thus reducing landfill requirements. Manufacturing industrial and packaging products from biological materials also reduces the amount of petroleum products currently standard in the industry.

Characterization of polymer nanocomposites by electron microscopy has been attempted since last decade. Main drives for this effort were analysis of dispersion and alignment of fillers in the matrix. Sample preparation, imaging modes and irradiation conditions became particularly challenging due to the small dimension of the fillers and also to the mechanical and conductive differences between filler and matrix. To date, no standardized dispersion and alignment process or characterization procedures exist in the trade. Review of current state of the art on characterization of polymer nanocomposites suggests that the most innovative electron and ion beam microscopy has not yet been deployed in this material system. Additionally, recently discovered functionalities of these composites, such as electro and photoactuation are amenable to the investigation of the atomistic phenomena by in situ transmission electron microscopy. The possibility of using innovative thinning techniques is presented.

In this article, we focus on the characterization of copper interconnect by Electron Backscattered Diffraction (EBSD) in the final aim of reliability issue investigation. In a first time we demonstrate that we achieve to characterize copper lines of 70 nm width after some improvements in sample preparation. Then, after showing that EBSD is well adapted to characterize our structure even for very small dimensions (line width smaller than 100 nm), we propose to associate Transmission Electron Microscope in scanning mode (STEM) to complete information given by EBSD and localize defects due to electromigration. We begin by highlighting the very good correspondence between EBSD map and STEM images on line with small microstructure and finally we apply both techniques on a tested copper line after electromigration. In this case we show the relevance of using STEM to localize the defect due to electromigration which can not be seen on EBSD map.

The imaging resolution of a focused ion beam (FIB) system is perhaps more difficult to measure even than that of a scanning electron microscope, especially with a heavy-ion (Ga, e.g.) FIB, because specimen erosion by sputtering is important [1,2]. Because of this beam size is sometimes used as measure of FIB beam quality instead of imaging resolution. A beam size measurement usually consists of a rise distance experiment where the beam is swept across a discontinuity such as a knife-edge; the change in current on the knife-edge is measured as a function of beam position and used to define a beam size. Although this is apparently a straightforward measurement there are numerous possibilities for errors, among which are statistical effects, specimen erosion, distortion due to implantation and other kinds of specimen damage. It is important to take these errors into account to avoid a misinterpretation of the result of the measurement and an incorrect estimate of the beam size. We consider some aspects and difficulties of the rise distance method, and some of the errors that can be encountered as a result of beam statistics and spatially varying secondary electron yields. Based on experiment and simulation, we find for a given beam and specimen that the result of a rise distance measurement can vary by a factor of three (3) due to statistical effects (beam noise) alone.

Reference Material 8820 (RM 8820) is a new scanning electron microscope calibration reference material for nanotechnology and nanomanufacturingtion recently released by NIST. This standard was developed to be used primarily for X and Y scale (or magnifi cation) calibrations of scanning electron microscopes from less than 10 times magnifi cation to more than 300 000 times magnifi cation, i.e., from about 10 mm to smaller than 300 nm range instrument fi eld of view (FOV). This standard is identifi ed as RM 8820. This is a very versatile standard, and it can also be used for calibration and testing of other type of microscopes, such as optical and scanning probe microscopes. Beyond scale calibration, RM 8820 can be used for a number of other applications, some of which will be described in this publication.

To understand the behavior of light scattered in seawater, it is necessary to know the size distribution of particles in seawater, as well as their composition (refractive index distribution) and complex shape. A method has been developed to determine marine PSDs and simultaneously characterize their chemical compositions by utilizing a scanning electron microscope (SEM) coupled with an energy dispersive spectrometer (EDS) and applying sophisticated image analysis techniques that minimized user bias including automatic image thresholding. The method was validated by verifying the PSD and chemical composition of Arizona test dust, which has a well-documented size distribution and chemical composition. PSDs of field samples collected from the coastal Long Island Sound and the remote South Pacific Ocean were also determined. Where applicable, PSDs agreed well overall with other PSD determining methods such as electroresistive counting and near-forward diffraction theory inversions. The method performed optimally when the particle mass on the filter was between 0.4mg and 1.0mg. With this in mind, measuring particle beam attenuation coefficient at 650nm (c650) can provide immediate feedback in the field to determine filter volumes for sample preparation.

Electron-excited x-ray spectrum image (XSI) elemental mapping can now be performed in remarkably short time, 30 seconds or less, with the silicon drift detector energy dispersive x-ray spectrometer (SDD-EDS). Major constituents (concentration, C > 0.1 mass fraction) and minor constituents (0.01 < C < 0.1) can be mapped with such short duration scans, and trace constituents (C < 0.01) can often be mapped in 300 second scans. Constraints imposed by the older Si(Li)-EDS are greatly reduced with the new SDD-EDS technology, enlarging the range of application of elemental mapping. While high speed mapping has numerous applications, mapping times up to 30 minutes duration are useful for higher pixel density that can reveal unexpected fine spatial details, finer than the x-ray interaction volume appears to permit. Longer duration SDD-EDS mapping enables recording a deeper x-ray gray scale, permitting compositional contrast to be observed at much lower values for major, minor, and trace constituents.

Recent helium ion microscope (HIM) imaging studies have shown the strong sensitivity of HIM induced secondary electron (SE) yields [1] to the sample physical and chemical properties and to its surface topography. This SE yield sensitivity is due to the low recoil energy of the HIM initiated electrons and their resulting short mean free path. Additionally, a material's SE escape probability is modulated by changes in the material's work function and surface potential. Due to the escape electrons' roughly 2eV mean energy and their nanometer range mean free path, HIM SE mode image contrast has significant material and surface sensitivity. The latest generation of HIM has a 0.35 nanometer resolution specification and is equipped with a plasma cleaning process to mitigate the effects of hydrocarbon contamination. However, for surfaces that may have native oxide chemistries influencing the secondary electron yield, a new process of low energy, shallow angle argon sputtering, was evaluated. The intent of this work was to study the effect of removing pre-existing native oxides and any in-situ deposited surface contaminants. We will introduce the sputter yield predictions of two established computer models and the sputter yield and sample modification forecasts of the molecular dynamics program, Kalypso. We will review the experimental technique applied to copper samples and show the copper grain contrast improvement that resulted when argon cleaned samples were imaged in HIM SE mode.

We give an overview of the design and planned operation of the metrological Scanning Probe Microscope (mSPM) currently under development at the National Measurement Institute Australia (NMIA) and highlight the metrological principles guiding the design of the instrument. The mSPM facility is being established as part of the nanometrology program at NMIA and will provide the link in the traceability chain between dimensional measurements made at the nanometer scale and the realization of the SI meter at NMIA. The instrument will provide a measurement volume of 100 μm × 100 μm × 25 μm with a target uncertainty of 1 nm for the position measurement.

The National Institute of Standards and Technology (NIST), Advanced Surface Microscopy (ASM), and the National Metrology Centre (NMC) of the Agency for Science, Technology, and Research (A*STAR) in Singapore have completed a three-way interlaboratory comparison of traceable pitch measurements using atomic force microscopy (AFM). The specimen being used for this comparison is provided by ASM and consists of SiO₂ lines having a 70 nm pitch patterned on a silicon substrate. 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 recommended wavelength for realization of the SI (Système International d'Unités, or International System of Units) meter. NIST used the C-AFM to participate in this comparison. ASM used a commercially available AFM with an open-loop scanner, calibrated by a 144 nm pitch transfer standard. In a prior collaboration with Physikalisch-Technische Bundesanstalt (PTB), the German national metrology institute, ASM's transfer standard was calibrated using PTB's traceable optical diffractometry instrument. Thus, ASM's measurements are also traceable to the SI meter. NMC/A*STAR used a large scanning range metrological atomic force microscope (LRM-AFM). The LRM-AFM integrates an AFM scanning head into a nano-stage equipped with three built-in He-Ne laser interferometers so that its measurement related to the motion on all three axes is directly traceable to the SI meter. The measurements for this interlaboratory comparison have been completed and the results are in agreement within their expanded uncertainties and at the level of a few parts in 104.

The first generation AFM based on piezoelectric tube scanners has high spatial resolution and performs well in qualitative measurements. However, it suffers from poor repeatability and accuracy due to the background curvature and crosstalk between the x-y-z axes, making it inadequate for quantitative metrology. We developed a new AFM platform with a x-y flexure scanner, decoupled from the z scanner, which has a highly orthogonal and flat scan. The high speed z scanner with minimized drive mass provides a fast z servo response, making true non-contact AFM practical. The new AFM can also be used in critical angle measurements of microstructures such as reflective LCD display substrates. The design concept of the new AFM was utilized to measure under-cut structures by intentionally changing the angle of the z scanner, enabling the measurement and imaging of undercut structures as well as vertical sidewalls for the first time in AFM history.

Ambient dynamic mode (tapping mode or intermittent-contact mode) AFM imaging has been used extensively for the characterization of the topography of nano structures. However, the results are beset with artifacts, because hard tapping of the AFM tip on sample surface usually causes premature tip damage. Through careful study of the cantilever amplitude and phase signals as functions of tip-to-sample distance, principle of non-contact AFM operation was discovered to enable high resolution and low tip damage AFM image acquisition [1, 2]. However, current study discovers that the conventional way of acquiring amplitude and phase versus distance curves gives erroneous non-contact operating range, because the tip gets damaged during the data acquisition process. A new technique is developed to reliably map the operating parameters of an intact tip that ensures the AFM be operated with the correct non-contact settings. Two examples are given to illustrate the successful applications of this new technique. The first example involves the size characterization of polystyrene latex (PSL) nano particles used for light scattering tool calibration. The second example is the development of robust recipes for the measurement of the depth of phase-shift mask trenches.

Three different methods for extracting zinc oxide (ZnO) and titanium dioxide (TiO₂) nanoparticles from commercially available sunscreen were investigated to determine the most appropriate route for producing a sample suitable for measuring the primary particle size. Direct dilution of the formulation, centrifugal methods and chemical washing were trialed in combination with ultrasonic processing and surfactant addition to generate samples that are suitable for particle size analysis. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used to monitor the extraction and re-dispersion process. Washing with hexane, methanol and water to remove the formulation, in combination with pulsed high-powered ultrasonication and the addition of a charge-stabilizing surfactant was found to be the most efficient way of producing de-agglomerated samples. DLS measurements gave average hydrodynamic particle diameters of 87 nm for ZnO and 76 nm for TiO₂, compared to equivalent spherical particle diameters of 21 ± 12 nm for ZnO (81 particles) and 19 ± 14 nm for TiO₂ (81 particles) obtained from TEM analysis.

Electron microscopy, along with many other surface science and analytical techniques, offers an array of complementary sub-techniques that provide additional information to enhance the primary analysis or imaging mode. Most electron microscopes are built with several additional ports for the installation of complementary analysis modules. One type of analysis which is particular useful in geology and semiconductor analysis is cathodoluminescence (CL). A new technique has been developed to allow complementary optical measurements using the electron beam from the SEM, compatible with most standard commercial SEM systems. Among the optical measurements accessible using the Cathodoluminescence Universal Extension (CLUE) module are CL, Raman, PL and EDX spectroscopy and imaging. This paper shows the advantages of using these complementary techniques, and how they can be applied to analysis of geological and semiconductor materials.

GaN nanofibers were sintered by electrospinning and analyzed by electron microscopy techniques to study morphology and grain size. After heat treatment, the fibers showed thinner mats with polycrystalline grains with size on the order of 10 nm. For the first time in electospun GaN, optical properties were investigated by room temperature cathodoluminescence. Despite polycrystallinity, the fibers produced a luminescence signal. The NBE might be blueshitfted (by 1.1 eV) by the electron-confinement effect of excitons in the nm-sized grains. The origin of the other two emissions is also compared to GaN fibres sintered by alternative techniques. The existence of a NBE signal from GaN nanofibres could open the door to applications in nanophotonics.

Unwilling deformations of secondary electron (SE) images due to charging of an insulating layer on materials is one of important issues for semiconductor industry applications of scanning ion microscopes (SIM). This paper presents a Monte Carlo model of SE emission from SiO₂ in which the charging induced by ion bombardment at the energy range of tens of keV is taken into account. A self-consistent calculation is carried out for the transport of a projectile ion, recoiled material atoms and SEs, the creation of space charges trapped in the material and the resultant electric field in/out the material. Drift motion of trapped charges is calculated as well, where the recombination with a charge of opposite sign is taken into account. Therefore, the evolution of the charging is simulated with successive arrivals of ions. Since the surface voltage is positive due to ejection of SEs and injection of positive ions, some of ejected SEs are drawn back to the surface and can rebound on it; these SEs are unable to produce a net emission. Dynamic changes in the SE yield and surface voltage are compared among He ions, Ga ions and low-energy (<1 keV) electrons, along with the space charge distributions and the in/out electric fields. The net SE yield is decreased during ion bombardment and finally it vanishes, which is different from the case of electron bombardment where the net SE yield (including BSEs) is kept to one due to a balance between coming and outgoing electrons. Even if there is not net emission of SEs, the surface voltage does not reach any steady-state condition but progressively increases due to successive injection of positive ions. The growth rate of the surface voltage depends on both the SE yield with no charging and the spatial distribution of the ions penetrating into the material.

We are reporting the development of a simulation tool with unique capabilities to comprehensively model an SEM signal. This includes electron scattering, charging, and detector settings, as well as modeling of the local and global electromagnetic fields and the electron trajectories in these fields. Experimental and simulated results were compared for SEM imaging of carbon nanofibers embedded into bulk material in the presence of significant charging, as well as for samples with applied potential on metal electrodes. The effect of the potentials applied to electrodes on the secondary emission was studied; the resulting SEM images were simulated. The image contrast depends strongly on the sign and the value of the potential. SEM imaging of nanofibers embedded into silicon dioxide resulted in the considerable change of the appeared dimensions of the fibers and as well as tone reversal when the beam voltage was varied. The results of the simulations are in agreement with experimental results.

Besides the use of the most sophisticated equipment, accurate nanometrology for the most advanced CMOS processes requires that the physics of image formation in scanning electron microscopy (SEM) being modeled to extract critical dimensions. In this paper, a novel Monte Carlo simulation code based on the energy straggling principle is presented, which includes original physical models for electron scattering, the use of a standard Monte Carlo code for tracking and scoring, and the coupling with a numerical device simulator to calculate charging effects.

Modeling artificial scanning electron microscope (SEM) and scanning ion microscope images has recently become important. This is because of the need to provide repeatable images with a priori determined parameters. Modeled artificial images are highly useful in the evaluation of new imaging and metrological techniques, like image-sharpness calculation, or drift-corrected image composition (DCIC). Originally, the NIST-developed artificial image generator was designed only to produce the SEM images of gold-on-carbon resolution sample for image-sharpness evaluation. Since then, the new improved version of the software was written in C++ programming language and is in the Public Domain. The current version of the software can generate arbitrary samples, any drift function, and many other features. This work describes scanning in charged-particle microscopes, which is applied both in the artificial image generator and the DCIC technique. As an example, the performance of the DCIC technique is demonstrated.

The relation between detector geometry and image contrast was studied using the Monte Carlo simulator, CHARIOT. The simulator is capable of modeling electron scattering in the specimen, but it can also model the electron trajectories outside the specimen under 3-D electric and magnetic fields as well as the detector energy response. SEM images of 10 nm thick structures on a flat substrate were examined. The results demonstrate that the image contrast changes more drastically by changing the angular window of the detector, rather than by changing the energy response function of the detector. Particularly, it is shown to be possible to optimize the image contrast and the contrast-to-noise ratio of the SEM image. The information obtained is useful for designing the SEM detector for specific applications.

Nanotechnology is a rapidly emerging field in which the material structures are of the size 100 nanometers or smaller. Thus, analyzing images at the nanoscale level is a challenging task. Users in this field are interested in image analysis and processing to draw conclusions such as the impact of various experimental conditions on the nature of the image and consequently their usefulness in several applications. This motivates our work that involves designing a system that will not only recognize similarities and differences among images, but do so efficiently and accurately. Features are representative of the manner in which images are compared by human experts by finding empirical data about particle sizes, material depth, inter-particle distances and so forth. In this work, we look into the use of features for comparison by implementing a feature-based algorithm on real image data sets from nanotechnology and thereafter using the results in processes such as clustering that are commonly applied by users to analyze images. We are able to effectively assess the feature-based approach in a real-world context as corroborated by our experimental evaluation.

At his residence, a victim in a double homicide had installed a home-built video surveillance system. The suspects either knew of or discovered this system and removed it. In a backyard at a location associated with the suspects was a barrel used for burning trash. Could charred debris recovered from a metal bowl found among the contents of the barrel be the remains of a VHS video cassette? A positive answer to the question was obtained through a combination of optical microscopy, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and Energy Dispersive Spectroscopy (EDS).

Detection and identification of human remains in situations in which they are calcined, disarticulated, and fragmented may be a challenging task. In such situations the non-biological materials that may be present in the dentition can provide the best evidence available for potential identification. Four human jaw segments were utilized. A known combination of dental resins was placed in each segment, when possible. Other restorations, pre-existing in the cadavers, were retained. The jaw segments were cremated in a commercial cremation oven for 2.5 hrs at 1010C. Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (SEM/EDS) was used to analyze the dentition and fragmented debris. Analysis with SEM/EDS demonstrated the ability to confirm brand of known dental resins placed in each cadaver. In addition, pre-existing materials in each jaw segment were profiled and a likely brand name suggested. It was shown that microscopic fragments of heat-altered materials could be identified and classified, adding another level of certainty in victim identification.

The 2009 National Academy of Sciences report on forensics focused criticism on pattern evidence subdisciplines in which statements of unique identity are utilized. One principle of bitemark analysis is that the human dentition is unique to the extent that a perpetrator may be identified based on dental traits in a bitemark. Optical and electron scanning methods were used to measure dental minutia and to investigate replication of detail in human skin. Results indicated that being a visco-elastic substrate, skin effectively reduces the resolution of measurement of dental detail. Conclusions indicate caution in individualization statements.

Gunshot residue particles (GSR) were examined using scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) to illustrate the size, shape, morphology, and elemental composition normally observed in particulate resulting from a discharged firearm. Determining the presence of lead (Pb), antimony (Sb), and barium (Ba), barring other elemental tags, fused together in a single particle with the correct morphology, is all that is required for the positive identification of GSR. X-ray photoelectron spectroscopy (XPS), however, can reveal more detailed information on surface chemistry than SEM/EDS. XPS is a highly surface-sensitive (≤ ~10 nm), non-destructive, analytical technique that provides qualitative information for all elements except hydrogen and helium. Nanometer-scale sampling depth and its ability to provide unique chemical state information make XPS a potential technique for providing important knowledge on the surface chemistry of GSR that complements results obtained from SEM/EDS analysis.

The investigation of gunshot residue (GSR) patterns for shooting range estimation is usually based on visualizing the lead, copper, or nitrocellulose distributions on targets like fabric or adhesive tape by chemographic color tests. The method usually provides good results but has its drawbacks when it comes to the examination of ammunition containing lead-free primers or bloody clothing. A milli-X-ray fluorescence (m-XRF) spectrometer with a large motorized stage can help to circumvent these problems allowing the acquisition of XRF mappings of relatively large areas (up to 20 x 20 cm) in millimeter resolution within reasonable time (2-10 hours) for almost all elements. First experiences in GSR casework at the Forensic Science Institute of the Bundeskriminalamt (BKA) have shown, that m-XRF is a useful supplementation for conventional methods in shooting ranges estimation, which helps if there are problems in transferring a GSR pattern to secondary targets (e.g. bloody or stained garments) or if there is no suitable color test available for the element of interest. The resulting elemental distributions are a good estimate for the shooting range and can be evaluated by calculating radial distributions or integrated count rates of irregular shaped regions like pieces of human skin which are too small to be investigated with a conventional WD-XRF spectrometer. Beside a mapping mode the milli-XRF offers also point and line scan modes which can also be utilized in gunshot crime investigations as a quick survey tool to identify bullet holes based on the elements present in the wipe ring.

Analysis of gunshot residues (GSR) is one of major areas in microparticle investigation. Results of the analysis usually have a high evidential value, but some information about potential secondary contamination by GSR is needed to maintain its value. A three-year study was carried out for ascertaining the level of possible secondary contamination monitoring GSR particles in urban means of transports in Prague (underground, trams, busses), taxi cars, randomly chosen civil vehicles, vehicles and trains of suburban transport, at places with a high concentration of people (supermarkets, hypermarkets, banks and financial institutions, premises of post offices). We also performed sampling at premises of the Institute of Criminalistics Prague (common areas, corridors, laboratory rooms), at police stations and in patrol cars of the Police of the Czech Republic, including Prague Metropolitan Police. Next, persons form selected professional groups of inhabitants (policemen, car mechanics, civilians without contact with a firearm and people who are in contact with hunting weapons - huntsmen and gamekeepers) were sampled as well.

The use of Bayesian principles in the reporting of forensic findings has been a matter of interest for some years. Recently, also the GSR community is gradually exploring the advantages of this method, or rather approach, for writing reports. Since last year, our GSR group is adapting reporting procedures to the use of Bayesian principles. The police and magistrates find the reports more directly accessible and useful in their part of the criminal investigation. In the lab we find that, through applying the Bayesian principles, unnecessary analyses can be eliminated and thus time can be freed on the instruments.

In some automated bullet identification systems, the similarity of striation marks between different bullets is measured using the cross correlation function of the compressed signature profile extracted from a land impression. Inclusion of invalid areas weakly striated by barrel features may lead to sub-optimal extraction of the signature profile and subsequent deterioration of correlation results. In this paper, a method for locating striation marks and selecting valid correlation areas based on an edge detection technique is proposed for the optimal extraction of the compressed signature profiles. Experimental results from correlating 48 bullets fired from 12 gun barrels of 6 manufacturers have demonstrated a higher correct matching rate than the previous study results without correlation area selection processing. Furthermore, an attempt to convert a traditional profile with multiple z-quantization (or gray scale) levels into a binary profile is made for the purpose of reducing storage space and increasing correlation speed.

The National Institute of Standards and Technology Standard Reference Materials (SRM) 2460 Standard Bullets and 2461 Standard Cartridge Cases are intended for use as check standards for crime laboratories to help verify that their computerized optical imaging equipment for ballistics image acquisitions and correlations is operating properly. Using topography measurements and cross-correlation methods, our earlier results for the SRM bullets and recent results for the SRM cartridge cases both demonstrate that the individual units of the SRMs are highly reproducible. Currently, we are developing procedures for topographic imaging of the firing pin impressions, breech face impressions, and ejector marks of the standard cartridge cases. The initial results lead us to conclude that all three areas can be measured accurately and routinely using confocal techniques. We are also nearing conclusion of a project with crime lab experts to test sets of both SRM cartridge cases and SRM bullets using the automated commercial systems of the National Integrated Ballistics Information Network.

Transmission-type laser scanning angle deviation microscopy (TADM) with NA=0.65 for three dimension (3D) measurement is presented. It is based on the theorems of geometrical angular deviation and surface plasmon resonance (SPR) and the use of the common-path heterodyne interferometry. When a laser beam defocuses on the surface of a transparent sample, the transmission light will be deviated a small angle from the optical axis and the deviation angle is proportional to the defocus length and the square of the numerical aperture. We used a SPR angular sensor and the common-path heterodyne interferometry to measure this deviation angle. Scanning the sample, the phase profile was measured and transferred to surface height pattern, the 3D surface profile was obtained in real-time. The results showed that the dynamic range and lateral and axial resolutions were equal to ±5.6 μm, 0.3 μm, and 3 nm, respectively.

In the field of diffraction microscopy, a coherent illuminating beam of finite extent impinges on a specimen and the resulting diffraction pattern is recorded. The complex transmission function of the specimen is recovered using iterative algorithms that exploit redundancies in the measured data. This is normally oversampling of the diffraction pattern when it is known the object or illumination is of the finite size. In the case of curved illumination, there is no direct relationship between the collection angle and the resolution of the recovered image. The result is a recovered image with varying resolution over the field of view as different parts of the object are illuminated by different wave-vectors. An extension of the Coherent Diffractive Imaging (CDI) technique (employing a single diffraction pattern) is to use multiple diffraction patterns collected from adjacent parts of the object and is called ptychography. In ptychography, translation of the illuminating wave across the specimen introduces translational diversity that leads to faster convergence of iterative phase retrieval as well as extending the field of view. In this paper we investigate the expression of resolution information in the diffraction pattern using curved illumination in order to facilitate specimen recovery with uniformly improved resolution over the entire field of view.

Coherent Diffractive Imaging (CDI) is a method of lensless imaging that reconstructs a target object from recordings of the diffraction pattern it generates when illuminated by a coherent source. A new method of scanning CDI, 'Ptychography,' was introduced recently and has been successfully demonstrated as a method of lensless microscopy at optical and x-ray wavelengths. Here we show how it can be applied to visible light microscopy to produce high resolution quantitative phase images of low-contrast objects, such as unstained cells.

While tapered and coated fibers are used as probes for scanning near-field optical microscopy SNOM), tapered coaxial probes and other structures are used in the microwave regime for broad band measurements. Aperture probes, tapered fibers and tapered waveguides have the inherent disadvantage that the radiation will have to pass a cutoff region. This is not the case for coaxial probes and for appropriately chosen transmission lines based on metallic wires. To enhance the energy transition for a tapered SNOM tip, the cladding can be split by milling longitudinal slits in it. We demonstrate the principle of mode conversion in the microwave region, building a tip for a scanning near-field microwave microscope SNMM) with a feed similar to a SNOM tip with the slits in the cladding. Transition to a single wire mode is made at the very end of the tip. With this new kind of SNMM tip we scan a test structure and demonstrate a resolution of 1/882 wavelengths for double passage operation.

Chromatic confocal microscopy is a common way to interrogate topologies and is well understood. Thin film reflectometry (TFR), on the other hand, is a way to monitor film thicknesses. Semiconductor and optics producing industries, e.g., require information about topological, film thickness or optical constants. We developed a spectrometric measuring system which is capable of determining high precision thin film thickness and topographic information of a specimen at the same time. The spectral intensity distribution reflected by a transparent thin film differs from a spectroscopic confocal observation by a chromatic measurement head, since the spectral interference fringes appear in the spectra. The spectrometer-based system interrogates both confocal, as well as thin film signals employing an analytical model of the chromatic shift of the measuring head, film composition and a least-square estimator. Hence, the advantage of this combined measuring system is the concurrent determination of film thickness and distance to the measuring head. By scanning the surface of a specimen laterally, a both tomo- and topological image can be acquired. Spacial measurements at test objects were carried out to demonstrate this measurement principle and the results are discussed.

We present the design and finite-difference time-domain (FDTD) simulation of a novel near-field visible light confinement probe operating at wavelength of 635nm, using nano-resonators embedded within a 2D slab photonic crystal waveguide (PCW). The 2D slab PCW is composed of triangular air holes of diameter 136nm and lattice constant a = 227nm etched through 1.2a thickness silicon nitride center slab layer and 0.4a thickness silicon dioxide cladding layers. Center evanescent peak was generated for TE excitation, with additional mode matching been considered to greatly reduce the propagation loss. The air slot inside the PCW center line defect creates the boundary condition for a one-and-a-half wavelength nano Fabry-Pérot resonating cavities designed to enhance the light throughput. The dominating travelling modes are blocked by the resonator to remove the side lobes in the near field, with the main lobe size being proportional to the size of the air slot. For air slot width of 45nm, the sub-wavelength light confinement can achieve 1/15^th of the wavelength, which is 1000 times enhancement comparing to that of the metal-coated fiber probe tip.

The domestic apple might well be called an 'extreme' fruit. In the arid Northwest United States, the fruit often tolerates surface temperatures ranging from -2 °C in the early spring to 50 °C in the heat of summer, and again to -2 °C during controlled postharvest storage for up to 12 months. During its 18-month existence, the apple maintains a cuticle that is dynamic and environmentally responsive to protect against 1) cellular water loss during desiccation stress and 2) excessive uptake of standing surface moisture. Physiological disorders of the peel such as russeting, cracking, splitting, flecking and lenticel marking, develop as epidermal cells respond to rapid changes in ambient conditions at specific developmental stages during the growing season. Resultant market losses underlie research investigating the nature of apple cuticle growth and development. Ultrastructural analysis of the pro-cuticle using scanning electron microscopy indicates an overlapping network of lipid-based distally-elongating microtubules--produced by and connected to epidermal cells--which co-polymerize to form an organic solvent-insoluble semi-permeable cutin matrix. Microtubule elongation, aggregation, and polymerization function together as long as the fruit continues to enlarge. The nature of lipid transport from the epidermal cells through the cell wall to become part of the cuticular matrix was explored using an FEI Helios NanoLab^TM DualBeam^TM focused ion beam/scanning electron microscope on chemically- and cryo-fixed peel tissue from mature or freshly harvested apples. Based on microtubule dimensions, regular projections found at the cell/cuticle interface suggest an array of microtubule-like structures associated with the epidermal cell.

High temperatures during wheat grain fill decrease starch and protein levels, adversely affecting wheat yield and flour quality. To determine the effect of high temperature on starchy endosperm cell development, grain (Triticum aestivum L. 'Butte 86') was produced under a 24/17°C or 37/28°C day/night regimen imposed from flowering to maturity and starch and protein deposition examined using scanning electron microscopy. The high temperature regimen shortened the duration of grain fill from 40 to 18 days. Under the 37/28°C regimen, A- and B-type starch granules decreased in size. A-type starch granules also exhibited pitting, suggesting enhanced action of starch degradative enzymes. Under both temperature regimens, protein bodies originated early in development and coalesced during mid to late development to form a continuous protein matrix surrounding the starch granules. Under the 37/28°C regimen, the proportion of protein matrix increased in endosperm cells of mature grain. Taken together, the changes in starch granule number and size and in protein matrix amount provide clues for understanding how high temperature during grain fill can affect end use properties of wheat flour.

Some agricultural industries generate large amounts of low value co-products/residues, including citrus peel, sugar beet pulp and whey protein from the production of orange juice, sugar and cheese commodities, respectively. National Program #306 of the USDA Agricultural Research Service aims to characterize and enhance quality and develop new processes and uses for value-added foods and bio-based products. In parallel projects, we applied scanning microscopies to examine the molecular organization of citrus pectin gels, covalent crosslinking to reduce debonding in sugar beet pulp-PLA composites and functional modification of whey protein through extrusion in order to evaluate new methods of processing and formulating new products. Also, qualitative attributes of fresh produce that could potentially guide germ line development and crop management were explored through fluorescence imaging: synthesis and accumulation of oleoresin in habanero peppers suggest a complicated mechanism of secretion that differs from the classical scheme. Integrated imaging appears to offer significant structural insights to help understand practical properties and features of important food co-products/residues.

Structure and histochemistry of mature seeds of Desmanthus illinoensis (Illinois bundle flower) show that the seed has typical legume structure. The seed can be separated into two major fractions including the seed coat/endosperm and the embryo. The seed coat consists of a cuticle, palisade sclereids, hour glass cells and mesophyll. Endosperm is attached to the inner portion of the seed coat and is thicker beneath the pleurogram in the center of the seed. The embryo consists mostly of two large cotyledons, the major storage structures of the seed. The cotyledons are high in protein which occurs in protein bodies. Protein bodies in the cotyledons include those without inclusions, those with phytin inclusions and those with calcium-rich crystals. The phytin inclusions are spherical and have high phosphorus and magnesium contents. The calcium-rich crystals are also included inside protein bodies and are druse-type crystals.

Atrazine is a wide-range herbicide. For over 50 years, atrazine has been used as a selective broadleaf herbicide in many capacities, from pre-plant to pre-emergence to post-emergence, depending on the crop and application. Currently, 96% of all atrazine used is for commercial applications in fields for the control of broadleaf and grassy weeds in crops such as sorghum, corn, sugarcane, pineapple and for the control of undesirable weeds in rangeland. Many panhandle wells have also detected atrazine in samples taken. The concern for the public is the long-term effect of atrazine with its increasing popularity, and the impact on public health. We investigated the effect of different concentrations of atrazine on Allium cepa (onion), a standard plant test system. We established a control with the Allium bulbs grown on hydroponics culture. Varying concentrations of atrazine was used on the standard plant test system, Allium cepa grown hydroponically. The mitotic indices varied and with higher doses, we observed various chromosomal abnormalities including sticky bridges, early and late separations, and lag chromosomes with higher doses of treatments. In the second part of the experiment, 0.1ppb, 1ppb, 10ppb, and 100ppb concentrations of atrazine were applied to established phytoplankton cultures from the Lake Tanglewood, Texas. Study with a Sedgwick-Rafter counter, a BX-40 Olympus microscope with DP-70 camera revealed a gradual shift in the phytoplankton community from obligatory to facultative autotroph and finally to a parasitic planktonic community. This explains the periodic fish kill in the lakes after applications of atrazine in crop fields.

Aeroallergens cause serious allergic and asthmatic reactions. Characterizing the aeroallergen provides information regarding the onset, duration, and severity of the pollen season that clinicians use to guide allergen selection for skin testing and treatment. Fluorescence Microscopy has useful approaches to understand the structure and function of the microscopic objects. Prepared slides from the pollen were observed under an Olympus BX40 microscope equipped with FITC and TRITC fluorescent filters, a mercury lamp source, an Olympus DP-70 digital camera connected to the computer with Image Pro 6.0 software. Aeroallergens were viewed, recorded and analyzed with DP Manager using the Image Pro 6.0 software. Photographs were taken at bright field, the fluorescein-isothiocyanate (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. The FITC filter reveals the green fluorescent proteins (GFP and EGFP), and the TRITC filter for red fluorescent proteins (DsRed). SEM proved to be useful for observing ultra-structural details like pores, colpi, sulci and ornamentations on the pollen surface. Samples were examined with an SEM (TM-1000) after gold coating and Critical Point Drying. Pollen grains were measured using the TM-1000 imaging software that revealed the specific information on the size of colpi or sulci and the distance between the micro-structures. This information can be used for classification and circumscription in Angiosperm taxonomy. Data were correlated clinical studies established at Allergy A.R.T.S. Clinical Research Laboratory.