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As a group of subject-matter experts in X-ray photoelectron spectroscopy (XPS) and other material characterization techniques from different countries and institutions, we write this document to raise awareness of an epidemic of poor and incorrect materials data analysis in the literature. This issue is a growing problem with many causes and very undesirable consequences. It contributes to what has been called a "reproducibility crisis", which is a recent concern of the U.S. National Academies of Science (Baker,2016; Harris, 2017; NASE&M, 2019).

Over the past three decades, the widespread utility and applicability of X-ray photoelectron spectroscopy (XPS) in research and applications has made it the most popular and widely used method of surface analysis. Associated with this increased use has been an increase in the number of new or inexperienced users which has led to erroneous uses and misapplications of the method. This article is the first in a series of guides assembled by a committee of experienced XPS practitioners that are intended to assist inexperienced users by providing information about good practices in the use of XPS. This first guide outlines steps appropriate for determining whether XPS is capable of obtaining the desired information, identifies issues relevant to planning, conducting and reporting an XPS measurement, and identifies sources of practical information for conducting XPS measurements. Many of the topics and questions addressed in this article also apply to other surface-analysis techniques.

Historically, dynamic secondary ion mass spectroscopy (D-SIMS) has been used to quantitatively monitor the depth distribution of species present in low concentrations in samples/devices. We are not aware of any manuscript that describes the use of time of flight–secondary ion mass spectroscopy (ToF-SIMS) to perform quantitative analysis of aluminum present at low concentrations in silicon carbide (SiC) wafer substrates. In this paper, we will show that ToF-SIMS is able to replicate D-SIMS analysis. However, analysis at the lowest concentrations requires the collection of more spectral images at each depth. Tables of sputtering rates and sputtering yields, in addition to relative sensitivity factors are provided. We also highlight the benefits of ToF-SIMS analysis.

Time of flight secondary ion mass spectrometry (ToF-SIMS) is frequently used to analyze industrial samples since it offers high (ppb) detection sensitivity, very high surface specificity (analysis of the top 1–3 surface layers during a spectral/image acquisition), high mass resolution (allowing the analyst the ability to separate Cu from C5H3 for instance), the ability to detect hydrogen, high depth resolution for depth profile measurements, and detection of high-mass fragments associated with molecular species/additives. In this manuscript, we demonstrate the advantages of ToF-SIMS including the ability to measure trace quantities of unexpected species on the surfaces of devices, and the ability to extract high-mass resolution information from data sets which were collected at degraded mass resolution. The importance of applying unbiased multivariate statistical analysis (MVSA) to the complete set of measured data is also demonstrated.

Fiber optic temperature sensors are used in a variety of harsh environment applications. We have explored use of such temperature sensors in commercial gas turbines to measure the temperature at various regions of interest within the turbine system. More specifically, fiber optic temperature rakes were designed and installed on a commercial gas turbine under full load conditions. This work will focus on failure mechanisms observed at multiple length scales that impact the performance of high temperature optical fiber sensors. It was found that Au-coated silica fibers, which are a standard in the industry, undergo various failure modes when subjected to combinations of high temperature and high vibration. More specifically, the Au coating became soft/ductile as the temperature is increased. We also observed that the Au coating was not well bonded to the silica fiber, as expected since there were no adhesion layers present. These effects led to significant damage of the fiber optic under high vibrations. We also found that vibrations from the gas turbine coupled into fundamental modes of the fiber optic probe assembly, which were analyzed by detailed dynamic mechanical analysis. This led to the fiber impacting the internal wall of the probe assembly, which caused further damage and failure of the fiber and the Au coating. The silica fibers returned from the field also exhibited significant twisting throughout most of their length. This suggests the fibers reached temperatures above their strain point (about 1000 C for pure silica glass), which is explained by either a) the strain point had been significantly reduced by the presence of the Ge dopant, or b) the temperature was higher than expected in the gas turbine exhaust region. It was also hypothesized that complex anelastic effects may play a role under the high temperature, high vibration environment experienced by the probes. Detailed structural analysis of the fiber optic temperature sensors by scanning electron microscopy, ToF-SIMS, and X-ray microscopy will be presented to corroborate the above simulations and proposed damage mechanisms. Finally, we note that the fiber Bragg gratings (FBG) present within the temperature probes provided promising temperature data, and were in fact not damaged/erased by the high temperature environment.

Compound semiconductors belong to the most important materials for optoelectronic applications. Many of them exhibit favorable optical properties, such as a direct energy band gap (in contrast to silicon) and high-absorption coefficients over a wide spectral range. Moreover, varying the composition of the compound or substituting some of its elements often allows for controlled band gap engineering and optimization for specific applications. Because many compound semiconductors enable efficient conversion of light into electricity and vice versa, they are commonly used materials for optoelectronic devices.

We demonstrate for the first time that multivariate statistical analysis techniques can be applied to atom probe tomography data to estimate the chemical composition of a sample at the full spatial resolution of the atom probe in three dimensions. Whereas the raw atom probe data provide the specific identity of an atom at a precise location, the multivariate results can be interpreted in terms of the probabilities that an atom representing a particular chemical phase is situated there. When aggregated to the size scale of a single atom (∼0.2 nm), atom probe spectral-image datasets are huge and extremely sparse. In fact, the average spectrum will have somewhat less than one total count per spectrum due to imperfect detection efficiency. These conditions, under which the variance in the data is completely dominated by counting noise, test the limits of multivariate analysis, and an extensive discussion of how to extract the chemical information is presented. Efficient numerical approaches to performing principal component analysis (PCA) on these datasets, which may number hundreds of millions of individual spectra, are put forward, and it is shown that PCA can be computed in a few seconds on a typical laptop computer.

The maximum autocorrelation factors technique (MAF) is becoming increasingly popular for the multivariate analysis of spectral images acquired with time-of-flight secondary ion mass spectrometry (ToF-SIMS) instruments. In this article, we review the conditions under which the underlying chemical information can be separated from the large-scale, non-uniform noise characteristic of ToF-SIMS data. Central to this pursuit is the ability to assess the covariance structure of the noise. Given a set of replicate images, the noise covariance matrix can be estimated in a straightforward way using standard statistical tools. Acquiring replicate images, however, is not always possible, and MAF solves a subtly different problem, namely, how to approximate the noise covariance matrix from a single image when replicates are not available. This distinction is important; the MAF approximation is not an unbiased statistical estimate of the noise covariance matrix, and it differs in a highly significant way from a true estimate for ToF-SIMS data. Here, we draw attention to the fact that replicate measurements are made during the normal course of acquiring a ToF-SIMS spectral image, rendering the MAF procedure unnecessary. Furthermore, in the common case that detector dead-time effects permit no more than one ion of any specific species to be detected on a single primary ion shot, the noise covariance matrix can be estimated in a particularly simple way, which will be reported. Copyright © 2011 John Wiley & Sons, Ltd.

Although polydimethylsiloxane (PDMS) transfer during microcontact printing (microCP) has been observed in previous reports, which generally focused on only one or a few different substrates, in this work we investigate the extent of PDMS transfer onto a series of surfaces with a wide range of hydrophobicities using an uninked, unpatterned PDMS stamp. These surfaces include clean silicon, clean titanium, clean gold, "dirty" silicon, polystyrene, Teflon, surfaces modified with PEG, amino, dodecyl, and hexadecyl monolayers, and also two loose molecular materials. The PDMS transferred onto planar surfaces is, in general, easily detected by wetting and spectroscopic ellipsometry. More importantly, it is detected by time-of-flight secondary ion mass spectrometry (ToF-SIMS) because of the sensitivity of this technique to PDMS. The effect of surface free energy on PDMS transfer in microcontact printing is investigated, and the relationship between the amount of PDMS in ToF-SIMS spectra and the surface tensions of initial surfaces is revealed. We show that PDMS transfer can be applied as a probe of surface free energies using ToF-SIMS, where PDMS preferentially transfers onto more hydrophilic surface features during stamping, with little being transferred onto very hydrophobic surface features. Multivariate curve resolution (MCR) analysis of the ToF-SIMS image data further confirms and clarifies these results. Our data lend themselves to the hypothesis that it is the free energy of the surface that plays a major role in determining the degree of PDMS transfer during microCP.

Time of flight secondary ion mass spectrometry (ToF-SIMS) and scanning electron microscopy (SEM) provide valuable complementary information about the molecular composition and morphology of biological samples, but both techniques are performed under high vacuum, which is not compatible with hydrated samples. Designing a suitable method to prepare biological (hydrated) samples for high vacuum conditions is important to obtain reliable and scientifically meaningful results from ToF-SIMS and SEM and to enable the routine use of these techniques for characterization. This article will compare freeze-drying and critical point drying for preparing adherent and nonadherent cells for ToF-SIMS and SEM analyses.

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) instruments produce raw data sets with a tremendous quantity of data. Multivariate statistical analysis (MVA) tools are being used to reduce the massive amount of chemical information into a smaller set of components that are easier to interpret and understand as a result of species association. Standard principal component analysis (PCA) is the most heavily used MVA algorithm in the ToF-SIMS community, and is frequently computed using the singular value decomposition (SVD). Other algorithms such as multivariate curve resolution (MCR) have also gained popularity over the past few years. In this work, we compare the as-measured ToF-SIMS spectrum and ion images with four MVA data analysis protocols: standard PCA, image-rotated SVD, spectra-rotated SVD, and a PCA-based MCR procedure. Image-rotated SVD and spectra-rotated SVD are closely connected to PCA and involve abstract rotations of the singular vectors that naturally arise during computation of the principal components via SVD. These rotations are designed to enhance either spatial contrast or spectral contrast in the components, respectively. We will show that the four MVA protocols provide essentially the same information, but accentuate different aspects of the sample's composition and lateral distribution, and that taken together these methods provide a more complete understanding of the sample. We will demonstrate that the component spectra estimated by MVA protocols assist the analyst in discovering minor constituents and understanding species correlation that would have been difficult, if not impossible, using univariate analysis protocols. For the data set described here, MVA tools identified unexpected species, which were not obvious in the as-measured data. Copyright © 2008 John Wiley & Sons, Ltd.

Cluster LMIGs are now regarded as the standard primary ion guns on time-of-flight secondary ion mass spectrometers (ToF-SIMS). The ToF-SIMS analyst typically selects a bombarding species (cluster size and charge) to be used for material analysis. Using standard data collection protocols where the analyst uses only a single primary bombarding species, only a fraction of the ion-beam current generated by the LMIG is used. In this work, we demonstrate for the first time that it is possible to perform ToF-SIMS analysis when all of the primary ion intensity (clusters) are used; we refer to this new data analysis mode as non-mass-selected (NMS) analysis. Since each of the bombarding species has a different mass-to-charge ratio, they strike the sample at different times, and as a result, each of the bombarding species generates a spectrum. The resulting NMS ToF-SIMS spectrum contains contributions from each of the bombarding species that are shifted in time. NMS spectra are incredibly complicated and would be difficult, if not impossible, to analyze using univariate methodology. We will demonstrate that automated multivariate statistical analysis (MVSA) tools are capable of rapidly converting the complicated NMS data sets into a handful of chemical components (represented by both spectra and images) that are easier to interpret since each component spectrum represents a unique and simpler chemistry. Copyright © 2008 John Wiley & Sons, Ltd.

ToF-SIMS spectra are formed by bombarding a surface with a pulse of primary ions and detecting the resultant ionized surface species using a time-of-flight mass spectrometer. Typically, the detector is a time-to-digital converter. Once an ion is detected using such detectors, the detector becomes insensitive to the arrival of additional ions for a period termed as the (detector) dead-time. Under commonly used ToF-SIMS data acquisition conditions, the time interval over which ions arising from a single chemical species reach the detector is on the order of the detector dead-time. Thus, only the first ion reaching the detector at any given mass is counted. The event registered by the data acquisition system, then, is the arrival of one or more ions at the detector. This behavior causes ToF-SIMS data to violate, in the general case, the assumption of linear additivity that underlies many multivariate statistical analysis techniques. In this article, we show that high-mass-resolution ToF-SIMS spectral-image data follow a generalized linear model, and we propose a data transformation and scaling procedure that enables such data sets to be successfully analyzed using standard methods of multivariate image analysis. Copyright © 2008 John Wiley & Sons, Ltd.

Laser-activation-modification of semiconductor surfaces (LAMSS) was carried out on silicon with a series of 1-alkenes. These laser spots were studied by time of flight secondary ion mass spectrometry (ToF-SIMS). The resulting spectra were analyzed using the multivariate curve resolution (MCR) method within the Automated eXpert Spectral Image Analysis (AXSIA) toolkit, and also by MCR and cluster analysis using commercially available toolboxes for Matlab: the PLS_Toolbox and the MIA_Toolbox, respectively. AXSIA based MCR generally finds three components for the spectral images: one for the background and two for the laser-activated spots, for both the positive and negative ion images. The negative ion component spectra from the spots show increased carbon and hydrogen signals compared to oxygen. They also show reduced chlorine and fluorine (contamination) peaks. In order to compare AXSIA–MCR results from different images, the AXSIA component spectra of different spots were further analyzed by principal components analysis (PCA). PCA of all of the negative ion components shows that component 1 is chemically distinct from components 2 and 3. PCA of all of the positive ion components yields the same result. The loadings plots of this PCA analysis confirm that component 1 generally contains fragments expected from the substrate, while components 2 and 3 contain fragments expected from an overlayer composed of alkyl chains in the spots. A comparison of the two MCR analyses suggests that roughly the same information can be obtained from AXSIA, which is not commercially available, and the PLS_Toolbox. Cluster analysis of the data also clearly separates the spots from the backgrounds. A key finding from these analyses is that the degree of surface functionalization in a LAMSS spot appears to decrease radially from the center of the spot. Finally, a comparison of atomic force microscopy (AFM) of the spots versus the AXSIA analysis of the ToF-SIMS data produced another important result, which is that the surface morphology is only weakly correlated with the LAMSS chemistry.

In this letter, we report a new and extremely rapid technique for surface modification, which we term laser activation modification of semiconductor surfaces or LAMSS. This method consists of wetting a semiconductor surface (e.g., silicon or germanium) with a reactive compound and then firing a highly focused nanosecond pulse of laser light through the transparent liquid onto the surface. The high peak power of the pulse at the surface activates the surface so that it reacts with the liquid with which it is in contact. Evidence for functionalization of the spots is given by ToF-SIMS imaging and small-spot XPS.

Silsesquioxane, with an empirical formula of RSiO 3/2 , has the potential to combine the mechanical properties of plastics with the oxidative stability of ceramics in one material [D.W. Scott, J. Am. Chem. Soc. 68 (1946) 356; K.J. Shea, D.A. Loy, Acc. Chem. Res. 34 (2001) 707; K.-M. Kim, D.-K. Keum, Y. Chujo, Macromolecules 36 (2003) 867; M.J. Abad, L. Barral, D.P. Fasce, R.J.J. William, Macromolecules 36 (2003) 3128]. The high sensitivity, surface specificity, and ability to detect and image high mass additives make time-of-flight secondary ion mass spectrometry (ToF-SIMS) a powerful surface analytical instrument for the characterization of polymer composite surfaces in an analytical laboratory [J.C. Vickerman, D. Briggs (Eds.), ToF-SIMS Surface Analysis by Mass Spectrometry, Surface Spectra/IMPublications, UK, 2001; X. Vanden Eynde, P. Bertand, Surf. Interface Anal. 27 (1999) 157; P.M. Thompson, Anal. Chem. 63 (1991) 2447; S.J. Simko, S.R. Bryan, D.P. Griffis, R.W. Murray, R.W. Linton, Anal. Chem. 57 (1985) 1198; S. Affrossman, S.A. O’Neill, M. Stamm, Macromolecules 31 (1998) 6280]. In this paper, we compare ToF-SIMS spectra of control samples with spectra generated from polymer nano-composites based on octabenzyl-polyhedral oligomeric silsesquioxane (BnPOSS) as well as spectra (and images) generated from multivariate statistical analysis (MVSA) of the entire spectral image. We will demonstrate that ToF-SIMS is able to detect and image low concentrations of BnPOSS in polycarbonate. We emphasize the use of MVSA tools for converting the massive amount of data contained in a ToF-SIMS spectral image into a smaller number of useful chemical components (spectra and images) that fully describe the ToF-SIMS measurement.

Much effort is currently being expended in nanotechnology and other fields to build biomimetic, or nature-inspired, materials. The first step in this process is often to develop a more complete understanding of the structure and chemistry of biological systems. In this article, we will compare and contrast data collected on a common biological sample, a butterfly wing, using a variety of analytical techniques. Transmission Electron Microscopy (TEM) was used in order to perform bright field imaging of the sample cross section; Light Microscopy (LM) and Scanning Electron Microscopy (SEM) were used to provide structural information of the outer wing surface at various magnifications; Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) was used in order to image the chemical composition of the outer most surface layer; and Focused Ion Beam (FIB) techniques were used to cut (micro machine) features into the wing.

Analytical instrumentation such as time-of-flight secondary ion mass spectrometry (ToF-SIMS) provides a tremendous quantity of data since an entire mass spectrum is saved at each pixel in an ion image. The analyst often selects only a few species for detailed analysis; the majority of the data are not utilized. Researchers at Sandia National Laboratory (SNL) have developed a powerful multivariate statistical analysis (MVSA) toolkit named AXSIA (Automated eXpert Spectrum Image Analysis) that looks for trends in complete datasets (e.g., analyzes the entire mass spectrum at each pixel). A unique feature of the AXSIA toolkit is the generation of intuitive results (e.g., negative peaks are not allowed in the spectral response). The robust statistical process is able to unambiguously identify all of the spectral features uniquely associated with each distinct component throughout the dataset. General Electric and Sandia used AXSIA to analyze raw data files generated on an Ion Tof IV ToF-SIMS instrument. Here, we will show that the MVSA toolkit identified metallic contaminants within a defect in a polymer sample. These metallic contaminants were not identifiable using standard data analysis protocol.

Microscopy & Microanalysis (M&M) stands as the premier meeting of the Microscopy Society of America, the Microanalysis Society, and the International Metallographic Society, Inc. We are pleased welcome to all the physical, life, and analytical scientists whose work encompasses the full range of microscopic and analytical techniques. In particular, we extend a warm welcome to those researchers who are new to our meeting, and are confident that you will find areas of specific interest in our meeting this year and for many years to come.

During the past century, there have been hundreds of manuscripts published reporting different aspects of sputtering. The purpose of this article is to summarize the trends observed when elemental and multicomponent materials are exposed to energetic ion beams. Attention is focused on low-energy (

Being able to differentiate surface from bulk defects on devices requires the use of complimentary characterization tools. In this article, we show how light microscopy, scanning electron microscopy, energy dispersive X-ray analysis, and time of flight secondary ion mass spectrometry provides complimentary information about the surface and sub-surface composition, topography, and microstructure of a semiconductor device. To create a gamma-ray spectroscopy detector, electrical contacts consisting of a blanket coated cathode and a pixilated anode can be deposited directly on opposite faces of a cadmium zinc telluride (CZT) crystal. The contact metallization must adhere to the surfaces, and the streets between adjacent anode pads must be free of residual metal and contaminants to avoid excessive interpixel leakage currents. The analysis reported below was used to validate the structure and composition of the contact metal stack and to characterize the streets of the anode pad array.

The radiation-induced decomposition of C4F9I and CF3I overlayers at 119 K on diamond (100) surfaces has been shown to be an efficient route to fluorination of the diamond surface. X-ray photoelectron spectroscopy has been used for photoactivation as well as for studying the photodecomposition of the fluoroalkyl iodide molecules, the attachment of the photofragments to the diamond surface, and the thermal decomposition of the fluoroalkyl ligands. Measured chemical shifts agree well with ab initio calculations of both C 1s and F 1s binding energies. It is found that chemisorbed CF3 groups on diamond (100) decompose by 300 K whereas C4F9 groups decompose over the range 300 to ∼ 700 K and this reactivity difference is rationalized on steric grounds. Both of these thermal decomposition processes produce surface CF bonds on the diamond. The surface CF species thermally decompose over a wide temperature range extending up to 1500 K. Hydrogen passivation of the diamond surface is ineffective in preventing free radical attack from the photodissociated products of the fluoroalkyl iodides; I atoms produced photolytically abstract H from surface CH bonds to yield hydrogen iodide at 119 K allowing diamond fluorination. The attachment of chemisorbed F species to the diamond (100) surface causes band bending as the surface states are occupied as a result of chemisorption. This results in a shift to higher binding energy of the diamond-related C 1s levels present in the surface and subsurface regions which are sampled by XPS on the diamond. The use of photoactivation of fluoroalkyl iodides for the fluorination of diamond surfaces provides a convenient route compared to other methods involving the action of atomic F, molecular F2, XeF2 and F-containing plasmas.

We provide a universal calibration of the W5%Re vs W26%Re (type‐C) thermocouple alloy which may be used in the temperature range of 32–2588 K. Our calibration is within the limits of standard error reported by Omega [The Omega Complete Temperature Measurement Handbook and Encyclopedia (Omega Engineering, Stamford, CT, 1989), pp. z8–z28] for their data in the temperature range of 255–2588 K, and rationally extends the calibration downward in temperature.

The interaction of atomic deuterium with diamond (100) has been studied by X-ray photoelectron spectroscopy (XPS). Reproducible cleaning and conditioning procedures have been developed using atomic hydrogen exposure and heating to 1450 K in ultrahigh vacuum. As the clean diamond surface is exposed to atomic deuterium, the FWHM of the C 1s transition initially broadens for low atomic deuterium exposures. Increasing the atomic deuterium exposure results in a sharpening of the C 1s transition. This is essentially reversible by stepwise heating to desorb the deuterium. The C 1s broadening/sharpening phenomenon may be due to the electronic inhomogeneity caused by partial deuteration of the surface region sampled by XPS. Complete deuteration leads to a more homogeneous chemical environment and thus the C 1s line sharpens. These results suggest that deep deuteration of diamond (100) may take place upon exposure to atomic deuterium. The inhomogeneity of the surface region caused by Ar + ion bombardment has a similar broadening effect on the C 1s line. Charging effects were found to be insignificant. Deuteration of the diamond (100) surface by atomic deuterium results in apparent shifts of the C 1s binding energy, dependent (in sign) upon n-type or p-type doping in the diamond. This is consistent with band bending effects in the surface region caused by the removal of the surface state by deuterium adsorption. It is demonstrated that graphite overlayers on diamond cannot be removed with atomic D or molecular oxygen at high temperatures.

We present results of chemical composition analysis across CdTe/CdS interfaces using depth profiling in Auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS). The analysis of these buried interfaces is typically challenging due to significant interface broadening due to CdTe initial roughness and developing roughness during depth profiling. We have developed two alternative methods for sample preparation, namely chemical etching and mechanical polishing, and we will present S conc. profiles obtained using both methods in samples grown with variable CdTe temperature. AES depth profiling near bottom of CdTe solar cells showed widening of S conc. profiles for the hottest CdTe as compared to the coldest CdTe. In addition, the peak S conc. decreases from the coldest to the hottest sample, suggesting that S out-diffusion from CdS is also temperature dependent. Finally we employ focused ion beam cross-sectioning and scanning electron microscopy to measure layer thicknesses, evaluate the success of the sample preparation methods, and to discuss the effects of interface roughness on S conc. profiles and Te-S interdiffusion.

Three-dimensional quantitative compositional analysis of nanowires is a challenge for standard techniques such as secondary ion mass spectrometry because of specimen size and geometry considerations; however, it is precisely the size and geometry of nanowires that makes them attractive candidates for analysis via atom probe tomography. The resulting boron composition of various trimethylboron vapour-liquid-solid grown silicon nanowires were measured both with time-of-flight secondary ion mass spectrometry and pulsed-laser atom probe tomography. Both characterization techniques yielded similar results for relative composition. Specialized specimen preparation for pulsed-laser atom probe tomography was utilized and is described in detail whereby individual silicon nanowires are first protected, then lifted out, trimmed, and finally wet etched to remove the protective layer for subsequent three-dimensional analysis.

Competition between two active adsorbates, O 2 and CCl 4 , on Fe(110) has been investigated using temperature programmed desorption, Auger spectroscopy, and reaction kinetic methods. It is found that preadsorbed oxygen decreases the tendency for CCl 4 to dissociate. A portion of this effect has to do with the titration of defect sites on the Fe(110) crystal which are especially active for promoting CCl 4 dissociation. Surprisingly, the production of FeCl 2 is enhanced in the presence of chemisorbed oxygen and the desorption temperature for FeCl 2 is also increased. Competitive adsorption kinetic experiments at 325 K, using mixed effusive beams of CCl 4 and O 2 , show that the reaction probability of CCl 4 at low coverages remains at unity for all gas mixtures studied. In contrast to CCl 4 behavior, the reaction probability of O 2 at low coverages is significantly decreased in the presence of CCl 4 . The negative effect of CCl 4 adsorption on oxygen adsorption capacity is more dramatic than the negative effect of oxygen adsorption on CCl 4 adsorption capacity at 325 K.

Auger spectroscopy and quantitative adsorption studies, using a calibrated O2 beam, have been utilized to study the adsorption of O2 on atomically clean Fe(110) in the temperature range of 90 to 920 K. Quantitative correlations between Auger measurements and adsorption uptake measurements have been demonstrated. Depending on the adsorption temperature and oxygen exposure, various iron oxide species are observed. In addition, phase transformations between the various iron oxide phases are observed and can be correlated with the migration of iron through the iron oxide layers formed on the Fe(110) surface. No thermal desorption products were detected from OFe(110) layers in the temperature range of 90 to 1050 K.

Temperature programmed desorption (TPD) and quantitative beam dosing adsorption studies have been utilized to study the interaction of CCl2F2 with Fe(110) in the temperature range 90–850 K. At 90 K, molecular CCl2F2 adsorption occurs and produces the following desorption products: CCl2F2 from the multilayer (98 K) and monolayer (122 K),: CCl2 (156 K), FeF2 (two desorption states near 700 K), and a high temperature iron chloride species which desorbs above 900 K. Irreversible dissociative adsorption of CCl2F2 occurs at 326 K and the resulting desorption spectra reveal a broad FeF2 desorption state, in the temperature range of ~ 700 to ~ 950 K, as well as the high temperature iron chloride desorption state. The only desorption product observed, following CCl2F2 adsorption at 850 K, is a high temperature iron chloride species. It is shown that the CCl2F2 molecule preferentially interacts with the Fe(110) surface via the “fluorine end” of the molecule. This interaction probably occurs at defect sites. Comparisons of the results obtained for the CCl2F2/Fe(110) system with the CCl 4 F(110) and C 2 Cl 4 Fe(110) systems are presented.

Specific bond breaking reactions are observed on surface defects on Fe(llO) when adsorbed layers of CCl4 or CCl2F2 are heated. For CCl2F2, CF bonds are broken at defect sites, producing FeF2 species and the: CCl2 diradical. For CC14, FeCl2species a : CCl2 species are produced at defect sites. It is shown that the yield of both: CCl2 and the corresponding iron dihalide may be enhanced by using Ar+ bombardment to produce surface defects (in a controlled manner) prior to halocarbon adsorption and reaction. Evidence for iron dihalide surface migration to produce clusters on defect sites is presented. Annealing experiments show that defects produced by Ar+ bombardment may be annealed away at temperatures below 400 K, while the defects which are naturally present on the crystal cannot be removed by annealing to T #62; 800 K.

Combinatorial materials libraries are becoming more complicated; successful screening of these libraries requires the development of new high throughput screening methodologies. Time of flight secondary ion mass spectrometry (ToF-SIMS) is a surface analytical technique that is able to detect and image all elements (including hydrogen which is problematic for many other analysis instruments) and molecular fragments, with high mass resolution, during a single measurement. Commercial ToF-SIMS instruments can image 500 microm areas by rastering the primary ion beam over the region of interest. In this work, we will show that large area analysis can be performed, in one single measurement, by rastering the sample under the ion beam. We show that an entire 70 mm diameter wafer can be imaged in less than 90 min using ToF-SIMS stage (macro)rastering techniques. ToF-SIMS data sets contain a wealth of information since an entire high mass resolution mass spectrum is saved at each pixel in an ion image. Multivariate statistical analysis (MVSA) tools are being used in the ToF-SIMS community to assist with data interpretation; we will demonstrate that MVSA tools provide details that were not obtained using manual (univariate) analysis.

Changes in the oxidation state of an element can result in significant changes in the ionization efficiency and hence signal intensity during secondary ion mass spectrometry (SIMS) analysis; this is referred to as the SIMS matrix effect [Secondary Ion Mass Spectrometry: A Practical Handbook for Depth Profiling and Bulk Impurity Analysis, edited by R. G. Wilson, F. A. Stevie, and C. W. Magee (Wiley, New York, 1990)]. The SIMS matrix effect complicates quantitative analysis. Quantification of SIMS data requires the determination of relative sensitivity factors (RSFs), which can be used to convert the as measured intensity into concentration units [Secondary Ion Mass Spectrometry: A Practical Handbook for Depth Profiling and Bulk Impurity Analysis, edited by R. G. Wilson, F. A. Stevie, and C. W. Magee (Wiley, New York, 1990)]. In this manuscript, the authors report both: RSFs which were determined for quantification of B in Si and SiO2 matrices using a dual beam time of flight secondary ion mass spectrometry...

We present a two-fold extension of previous work on Atomic Force Microscope-based chemomechanical functionalization: (1) chemomechanical nanografting, which extends chemomechanical functionalization to a more stable initial surface, and (2) linewidth studies that show the impact of force and Atomic Force Microscope probe tip wear on patterning resolution. Alkene, alcohol, and alkyl halide molecules were nanografted to silicon and imaged with in situ atomic force microscopy, time-of-flight secondary ion mass spectrometry with Automated eXpert Spectrum Image Analysis, and scanning electron microscopy. Chemomechanical nanografting demonstrated linewidths down to 50 nm. Lines written on hydrogen-terminated silicon were used to explore the impact of tip radius and tip wear on linewidth when using Si 3 N 4 coated tips.

A facile method for chemically functionalizing diamond surfaces has been developed using x-ray irradiation of perfluoroalkyl iodide layers on the surface. Perfluoroalkyl radicals chemically bond to the diamond surface and can be thermally decomposed to produce strongly bound surface C-F bonds that are stable at high temperatures.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.