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Hybrid vapor deposition is one of the most appealing processes for perovskite photovoltaics fabrication, thanks to its versatile nature. By using sequentially different vapor deposition processes tailored to the inorganic and organic perovskite precursors' peculiarities, this type of process gives access to the full potential of vapor deposition. While vapor deposition of metal halides is well understood and mastered, vapor deposition of organohalide species is much more delicate (degradation of vapors, high vapor pressure, setup‐specific constraints). Here, a novel close space sublimation system is reported and in‐depth insights on the conversion into perovskite of a metal halide template are provided. In this evolution of the process, the substrate coated with metal halide template and the organohalide source are loaded together in a dedicated holder, then transferred into a vacuum chamber on a heating element already at temperature setpoint. The system enables a simple, fast, low‐cost, and easy‐to‐reproduce organohalide vapor deposition process. The formation of the perovskite in situ and identification different conversion regimes are studied. Furthermore, the influence of the chemical environment and chamber design on the process are discussed. Compositional tuning and additive engineering in the process are processed and fabricate proof of concept photovoltaic devices reaching high fill factors of 80% and 17% power conversion efficiency for a bandgap of 1.63 eV. [ABSTRACT FROM AUTHOR]

Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy‐based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu‐Zr nanoglass synthesized by magnetron sputtering. These analyses provide first‐time in‐depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time‐of‐flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable. [ABSTRACT FROM AUTHOR]

By utilizing time of flight secondary ion mass spectrometry (TOF SIMS), the degradation processes of quantum dot core components and the surface ligands were studied. Intentionally degraded QLED samples were prepared, and the TOF SIMS mass composition signals of each layer within the QLEDs are estimated. The result of the analysis gives possible structural information of the degraded species induced in the device, providing useful insights for further developments of highly efficient R/G/B quantum dot materials. [ABSTRACT FROM AUTHOR]

Secondary Ion Mass Spectrometry (SIMS) extracts chemical, elemental, or isotopic information about a localized area of a solid target by performing mass spectrometry on secondary ions sputtered from its surface by the impact of a beam of charged particles. This primary beam sputters ionized atoms and small molecules (as well as many neutral particles) from the upper few nanometers of the sample surface. The physical basis of SIMS has been applied to a large range of applications utilizing instruments optimized with different types of mass analyzer, either dynamic SIMS with a double focusing mass spectrometer or static SIMS with a Time of Flight (TOF) analyzer. Here, we present a short review of the principles and major applications of three different SIMS instruments located in Switzerland.

Visible-light irradiation of phthalimide esters in the presence of the photosensitizer [Ru(bpy)3]2+ and the stoichiometric reducing agent benzyl nicotinamide results in the formation of alkyl radicals under mild conditions. This approach to radical generation has proven useful for the synthesis of small organic molecules. Herein, we demonstrate for the first time the visible-light photosensitized deposition of robust alkyl thin films on Au surfaces using phthalimide esters as the alkyl radical precursors. In particular, we combine visible-light photosensitization with particle lithography to produce nanostructured thin films, the thickness of which can be measured easily using AFM cursor profiles. Analysis with AFM demonstrated that the films are robust and resistant to mechanical force while contact angle goniometry suggests a multilayered and disordered film structure. Analysis with IRRAS, XPS, and TOF SIMS provides further insights.

In this study, the structure, chemical composition and topography of oxide layers produced on the surface of the AISI 321 austenitic steel in the annealing process were analyzed. Heat treatment was done at 980°C temperature for 1 hour time in different conditions. The annealing was done in a ceramic furnace in oxidation atmosphere and in vacuum furnaces with cylindrical molybdenum and graphite chambers. The analysis was carried out using the following methods: a scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectrometer (EDX), a transmission electron microscope (TEM) equipped with an energy-dispersive X-ray spectrometer (EDX), an X-ray diffractometer (XRD), a secondary ion mass spectrometer with time-of-flight mass analyzer (TOF SIMS) and an atomic force microscope (AFM). The oxide layer formed during annealing of the AISI 321 steel at 980°C consisted of sub-layers, diversified in the chemical composition. The thickness of the oxidized layer is depended on the annealing conditions. In a ceramic furnace in oxidation atmosphere, the thickness of the oxide layer was of 300-500 nm, in a vacuum furnace with molybdenum and graphite heating chambers, it ranged from 40 to 300 nm and from a few to 50 nm, respectively. TOF SIMS method allows to get average (for the surface of 100 μm × 100 μm) depth profiles of concentration of particular elements and elements combined with oxygen. In oxide layers formed in vacuum furnaces there are no iron oxides. Titanium, apart from being bounded with carbon in carbides, is a component of the oxide layer formed on the surface of the AISI 321 steel.

High resolution Scanning Auger Electron Spectroscopy (AES) and Time-of-Flight Secondary Ion Mass-Spectrometry (ToF SIMS) were used to investigate structure and elemental composition variation of both across an array of TiO 2 nanotubes (NTs) and single tube of an array. The TiO 2 NT array was grown by anodic oxidation of Ti foil in fluorine-containing ethylene glycol electrolyte. It was found that the studied anodic TiO 2 nanotubes have a layered structure with rather sharp interfaces. The differences in AES depth profiling results of a single tube with the focused primary electron beam (point analysis) and over an area of 75 μm in diameter of a nanotube array with the defocused primary electron beam are discussed. Depth profiling by ToF SIMS was carried out over approximately the same size of a nanotube array to determine possible ionic fragments in the structure. The analysis results show that the combination of both mentioned methods is useful for a detailed analysis of nanostructures with complex morphology and multi-layered nature. [ABSTRACT FROM AUTHOR]

X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry and X-ray diffraction were employed to study the effect of intense mechanical treatment on the surface chemical state, composition and structure of a commercial biomedical CoCrMo alloy ('Bondi-Loy'). The ultrasonic impact treatment of the alloy in air with duration up to 30 s was found to cause the deformation-enhanced oxidation and deformation-induced surface segregation of the components and impurities from the bulk. The compositionally inhomogeneous mixed oxide layer formed under impact treatment was composed mainly of Cr2O3 and silicon oxide with admixture of CoO, MoO2, MoO3 and iron oxide/hydroxide, the latter being transferred onto the alloy surface from the steel pin. The impact treatment promoted a progressive accumulation of carbon on the alloy surface due to its deformation-induced segregation from the bulk and deformation-induced uptake of hydrocarbons from the ambient; concurrently, the dissolution/refinement of carbides originally present in the as-cast CoCrMo alloy occurred. The impact treatment gave rise to a two-fold increase in the volume fraction of the martensitic hcp ε-phase, a 30% increase in the surface microhardness and improved resistance to corrosion in the solution of artificial saliva compared to the as-polished alloy. [ABSTRACT FROM AUTHOR]

There are several techniques like time of flight secondary ion mass spectrometry (ToF SIMS) that require a special protocol for preparation of biological samples, in particular, those containing single cells due to high vacuum conditions that must be kept during the experiment. Frequently, preparation methodology involves liquid nitrogen freezing what is not always convenient. In our studies, we propose and validate a protocol for preparation of single cells. It consists of four steps: (i) paraformaldehyde fixation, (ii) salt removal, (iii) dehydrating, and (iv) sample drying under ambient conditions. The protocol was applied to samples with single melanoma cells i.e. WM115 and WM266-4 characterized by similar morphology. The surface and internal structures of cells were monitored using atomic force, scanning electron and fluorescent microscopes, used to follow any potential protocol-induced alterations. To validate the proposed methodology for sample preparation, ToF SIMS experiments were carried out using C 60 + cluster ion beam. The applied principal component analysis (PCA) revealed that chemical changes on cell surface of melanoma cells were large enough to differentiate between primary and secondary tumor sites. Subject category : Mass spectrometry. [ABSTRACT FROM AUTHOR]

The most recent advances in the identification and determination of organic constituents in paintings and other polychrome objects using mass spectrometry (MS)-based techniques are reviewed. The latest achievements in gas chromatography (GC)-MS and pyrolysis (Py-) GC-MS are mainly related to sample pretreatment protocols and to the employment of double-shot or laser desorption pyrolysis, respectively. MS techniques based on soft ionization methods such as matrix assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) are discussed. So far, MALDI and ESI MS have been mainly used in the characterization of proteinaceous materials, but further applications are definitely emerging, e.g., in the fields of lipids, resins, and organic colorants analysis. Chemical imaging by time-of-flight secondary ion mass spectrometry (TOF SIMS), formerly applied to the detection and localization of lipid binders and inorganic materials, has been recently extended to proteins. Finally, the potential of niche techniques such as direct temperature resolved mass spectrometry (DTMS) and direct analysis in real time (DART) MS are outlined. [ABSTRACT FROM AUTHOR]

Any noble gas characterization that includes chemical ionization for the detection process is hard to manage because of the very high ionization potential: the range is from 10 to 25eV; electronic affinity is also close to zero. So ionization processes used in secondary ion mass spectroscopy (SIMS) analysis have very poor cross section. It is known that amorphous carbon mechanical properties are changed by implant; sp2/sp3 ratio and H content in the film are modified, allowing high density and good transparency needed for dry etching and lithography steps. In this paper, we propose to monitor secondary ion clusters C x-H y by time of flight-SIMS to obtain information on amorphous carbon layer implanted with Ar and to study C n/C5 ratio to understand sp2/sp3 ratio behavior. Further consideration on 13CH as hydrogen representative will be addressed. A binary collision code Stopping and Range of Ions in Matter (SRIM) was used to estimate the depth of the region damaged by Ar+ implantation. In implanted samples, the profiles of C x-H y clusters have an in-depth gradient. This is an indication that the film was involved in an energy release process. Therefore, these profiles give information on the implanted region even if the Ar profile is not collected. Although the SIMS technique uses ion beams that produce damages similar to those due to the implant process, a 13CN depth profile behavior was found able to discriminate between damage effects produced by that or the other. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Time of flight secondary ion mass spectrometry (ToF-SIMS) has become a fundamental analytical technique in cultural heritage studies to obtain the identification and distribution of organic components present in artworks. A sample taken from the soldier's golden shield decoration in the fresco Vela della Castità (San Francesco Lower Basilica, Assisi) was studied. The metal leaves for gilding decoration on wall paintings are usually applied using an oil-resin mordant as adhesive. In this work, organic and inorganic compounds used in this peculiar painting technique were identified by ToF-SIMS technique. High mass resolution spectrometry was applied for the chemical characterization of organic materials present in oil-resin binding media and red lake paint layer. Presence of azelaic, palmitic and stearic acids proved the nature of the oil binder between plaster and tin leaf and between tin and gold leaf. The analyses revealed also the presence of colophony, a natural resin used as an adhesive in this painting technique. Furthermore, the fresco cross section was studied using ToF-SIMS imaging. ToF-SIMS results agree with and are complementary to those obtained by other analytical techniques: scanning electron microscopy with X-ray microanalysis and Fourier transform infrared spectroscopy. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Currently, information of species recognition on parchments is provided either using proteomics or DNA analysis. Each technique presents with inherent difficulties, and sometimes, it is not possible to obtain an unambiguous result. In this work, the application of time-of-flight secondary ion mass spectrometry paired with chemometrics, namely principle component analysis, to the analysis of parchment specimens has been investigated in order to assess if any information may be gleaned and help in the process of recognition or even providing any further information to conservators to be used for preservation of historical parchment. A series of specimens of various ages and species were analysed on both skin and flesh sides. Results indicate that it is fairly straightforward to distinguish between goat and sheep while calf is more difficult to separate from other species. In addition, an unknown sample exhibits data that would classify it as a goat specimen. More work is needed to ascertain which side is being analysed for any unknown materials as the behaviour varies amongst the species examined in this work. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and high-resolution scanning electron microscopy are well-acknowledged tools in materials characterization. The ability to map chemical species on the surface of an investigated sample with often low mass detection limits makes ToF-SIMS an essential tool in fields where many question marks concerning degradation processes and damage mechanisms exist. The aim of this paper is to describe the power of data fusion of ToF-SIMS and high-resolution scanning electron microscopy results employing computational methods for multivariate data analysis such as principal component analysis. As a case study the investigation of hydrogen distribution in an artificially charged duplex stainless steel microstructure is presented aiming on a better understanding of hydrogen embrittlement. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The identification of pigments applied in ancient paintings is of great importance for art conservation and history. In this work, pigment samples from the 19th century Korean Buddhist painting (taenghwa) at the Hwangnyongsa temple were analyzed using two analytical techniques: portable X-ray fluorescence (XRF) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Portable XRF was used to obtain elemental information about the pigments applied in the Korean guardian Buddhist painting. The XRF results revealed the characteristic elements in the pigments that were commonly used in that period. The qualitative and non-destructive XRF analyses of pigment layers of the Buddhist painting were compared with results obtained using the micro-destructive ToF-SIMS technique. The ToF-SIMS spectra of the pigments showed characteristic elemental peaks such as Pb+, Cu+, Hg+, Al+, and hydrocarbon ions for the white, green, red, blue, and black areas in the positive ion mode and CO3−, OH−, S−, Cl−, and CnH− in the negative ion mode, respectively. The XRF and ToF-SIMS results show that the white, green, and red areas in the Buddhist painting were painted with lead white, malachite, atacamite, cinnabar, and mars red as single or mixed pigments. Smalt and carbon were used to depict the blue and black areas in the Buddhist painting, respectively. ToF-SIMS combined with complementary methods such as portable XRF provides important information about ancient painting materials on a sub-micrometer scale. Therefore, by combining these complementary techniques, a thorough characterization of each pigment can be obtained, allowing for a proper strategy for the restoration process. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An approach for quantification of time-of-flight (ToF)-SIMS depth profiling data is demonstrated using an independently characterised multilayer, an AlGaAs/GaAs stack from certified reference material BAM-L200. The sample was studied with a Bi cluster ion source as the analysis projectile and a Cs+ sputter beam. Under these conditions, the negative secondary ion yield is significantly enhanced, especially for cluster ions comprising all possible elemental combinations. Each cluster ion carries a number of sputtered neutrals so if all cluster ions containing an element could be collected and identified, a large population of secondary neutrals will be included in the analysis, improving the analytical signal and approaching a 'matrix-effect-free' measurement. By measuring the intensities of a range of secondary cluster ions of AliGajAsk− where i, j, k are integers such 0, 1, 2, and so on, the atomic counts for each major element were accumulated based on the elemental contents of those cluster ions. The summed atomic counts were then normalised without using the more common approach of applying relative sensitivity factors. The resulting elemental depth profiles show an excellent match to the structure and stoichiometry of the sample. The quantitative relationship of various elements and the interface appearance derived by this cluster ion approach are strongly competitive to the results available from XPS. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Triterpenoid resins, such as dammar resin and mastic resin, are natural products used as protective varnishes on paintings. Dammar resin consists of a large amount of triterpenoid molecules including two triterpenic acids: oleanolic acid and ursolic acid. Similarly, mastic resin is a complex blend of terpenoids but containing oleanolic acid. In this paper, high-mass-resolution time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been used to characterize the fragmentation patterns of oleanolic acid and ursolic acid. The hypothesized fragmentation pathways for these triterpenic acids have also been discussed. In order to distinguish between these two structural isomers, principal component analysis (PCA) has been adopted. This multivariate statistical analysis technique permits to identify the characteristic fragments and discriminates between very similar mass spectra. In addition, dammar resin and mastic resin have been characterized. A selection of characteristic peaks from ursolic and oleanolic acids mass spectra has been used to build a dataset for a multivariate analysis to compare triterpenoid resins and triterpenic acids. The results of PCA have revealed that mastic resin is strictly related to oleanolic acid, whereas dammar resin is differentiated by ursolic acid fragments. This study confirms that, in the cultural heritage field, the time-of-flight secondary ion mass spectrometry technique combined with PCA can be a powerful tool to investigate the chemical composition of organic compounds with very complex composition. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This work presents a methodology to characterise the surface of Scots pine wood samples cut at different geometries by performing principal component analysis and non-negative matrix factorisation (NMF) of ToF-SIMS data. With the aid of two standard samples of lignin organosolv and cellulose, the NMF results reduced the data to two compounds which are representative of the surface coverage of lignin and cellulose. Differences between the relative amounts of lignin and cellulose in early and late wood were in agreement to the anatomy of wood, making the multivariate analysis a potential way to differentiate species and potentially ages of the wood in terms of their natural components. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Previous XPS investigations of insulating poly(o-aminophenol) (PoAP), electrosynthesized by cyclic voltammetry on Pt substrates, revealed the formation of a thin film of about 7 nm of thickness, firmly adherent onto the electrode surface and stable even under Ultra High Vacuum (UHV) conditions. A constant repeat formula made of alternating quinoneimine and monomer units was derived with polymer chains terminating as carbonyl-type groups. Based on these findings, we have continued our investigation on insulating PoAP by employing time-of-flight SIMS whose superior surface sensitivity is well-known. The aim was to corroborate the polymer structure with particular reference to the top surface layers in view of possible bio-applications and to understand the possible way of interaction with the underlying platinum electrode surface. In order to do this, we analyzed PoAP films grown at different levels of the electrochemical synthesis (1, 5, and 20 scan cycles) and the platinum substrate itself. The individuation of the main characteristic fragments and the behavior of their intensity by varying the stage of the electropolymerization allowed to confirm the polymer structure and the presence of terminating carbonyl groups. Remarkably, from the analysis of the PoAP/Pt interface at the early stage of the polymer formation, it was possible to discern that polymer chains tend to interact with the electrode surface preferentially by the nitrogen atom of the oxidized monomers. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new rare-earth-free NaZnPO4:Mn2+ (NZP:Mn) phosphor powder has been developed by our group and investigated meticulously for the first time using secondary ion mass spectroscopy and chemical imaging techniques. The studies confirmed the effective incorporation of Mn2+ into the host lattice, resulting in an enhancement of photoluminescence intensity. Phase purity has been verified and structure parameters have been determined successfully by Rietveld refinement studies. The NZP:Mn phosphor powder exhibits strong absorption bands in the ultraviolet and visible (300-470 nm) regions with a significant broad yellow-green (~543 nm) emission due to the characteristic spin forbidden d-d transition (4T1→6A1) of Mn2+ ions, indicating weak crystal field strength at the zinc-replaced manganese site. The decay constants are a few milliseconds, which is a pre-requisite for applications in many display devices. The results obtained suggest that this new phosphor powder will find many interesting applications in semiconductor physics, as cost-effective light-emitting diodes (LEDs), as solar cells and in photo-physics. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

CaS:Eu 2+ thin films were deposited on Si (100) substrates using the pulsed laser deposition technique to investigate the effect of argon (Ar), oxygen (O 2 ), and vacuum deposition atmospheres on the structural, morphological and photoluminescence properties of the thin films. The phosphor target was ablated using a 266 nm Nd: YAG laser. X-ray diffraction, atomic force microscopy, scanning electron microscopy, energy dispersive X-ray, fluorescence spectrophotometry and time-of-flight secondary ion mass spectrometry were used to characterize the thin films. The thin films prepared in oxygen were essentially amorphous, while those prepared in argon and vacuum showed some degree of crystallinity. The film deposited in Ar showed better photoluminescence intensity than those deposited in an O 2 and vacuum. The emission observed at around 650 nm for all the films is attributed to the transitions from the excited 4 f 6 [ F 0 7 ] 5 d 1 ( t 2 g ) state to the ground state 4 f 7 ( S 7 / 2 8 ) of the Eu 2+ ions. The emission at 618 nm, which is more prominent in the film prepared in O 2 , is ascribed to the D 5 → 0 F 2 7 transitions in Eu 3+ , suggesting that Eu 2+ was unintentionally oxidized to Eu 3+ . The atomic force microscopy data showed that the film prepared in argon was rougher than those prepared in oxygen and vacuum. [ABSTRACT FROM AUTHOR]

Present study considers the possibility of using high-mass clusters ions detected by TOF-SIMS for the depth profiling of implanted atoms. The Te and Se samples were implanted with the Bi + ions at the energy of 500 keV to a fluence of 1 × 10 15 cm −2 . SIMS depth profiles were measured with the TOF SIMS 5 working in the dual-beam mode (Bi + primary beam and Cs + sputter beam). The analysis of all bismuth-related profiles in Te demonstrates that Bi + ions create just surface maxima, and BiTe x − and CsBi + clusters create profiles of a similar shape which repeat well the shape of the bismuth ion profiles predicted by SRIM (Simulation of the stopping and Range of Ions in Matter) with the appropriate implantation parameters. However the secondary ion yield of BiTe x (3 ≤ x ≤ 7) clusters are higher than the yield of CsBi + by one order of magnitude. Qualitatively similar results were obtained for Bi implanted Se, although the intensity of all clusters ions was substantially lower. Further experiments and thorough analysis are required to justify the use of high-mass clusters in obtaining the reproducible depth profiles with improved detection limits. [ABSTRACT FROM AUTHOR]

Surface cleanness is crucial for reducing defect density of the semiconductor wafers. Organic contamination or residue on the wafer surface will lead to unintentional hydrophobization changes and haze formation and thus the performance of the subsequent wafer processes, such as film deposition or etching. Fatty acid salt is a common anionic surfactant. The residue of fatty acid salt will result in uneven etch of silicon and silicon nitride, which eventually causes particle issues. Time-of-flight SIMS was employed in this work to detect fatty acid residue on silicon, silicon oxide and silicon nitride wafers. The outgassing of the wafer container has been found to contribute to the fatty acid residue on the wafer surface. The outgassing of three different brands of wafer boxes was compared by investigating the adsorption on the wafers after fresh wafers were stored in boxes for a series of time duration. Different wafers also showed varied ability to absorb fatty acid, which can be attributed to electric dipole strength and concentration on the wafer surface. Time-of-flight SIMS and Fourier transform infrared spectroscopy analysis results showed that the difference in outgassing performance of different wafer boxes were due to the release agent residue on inner surface of the wafer boxes. More reliable results of fatty acid salt have been obtained on the wafers kept in the boxes with less outgassing. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

PVA based hydrogel was synthesised using, as crosslinking agent, trisodium trimetaphosphate (STMP) and its morphology was modified inducing a microporous structure to obtain potential substitutes for cartilage tissue. The hydrogel was characterised by Infrared Spectroscopy combined with Time of flight mass spectrometry (ToF-SIMS) that confirmed the successful occurrence of crosslinking reaction, the hyphotised crosslinking arm and its homogeneous distribution. The mechanical spectra of the fully hydrated samples confirmed covalently crosslinked systems with a rheological behaviour similar to that of tibial cartilage. Further analysis in terms of water content measurements, thermal stability and cytotoxicity confirmed the applicability of such a hydrogel as cartilage substitute. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Highlights: [•] We examine changes of the hydrogenated diamond surface upon oxidation. [•] Plasma, piranha treatments and UV irradiation in oxygen atmosphere were used to generate carbon oxygen bonds. [•] ToF SIMS coupled the photoelectron spectroscopies were used to investigate the nature of these carbon oxygen bonds. [•] Result show that plasma and piranha treatments lead to formation of strong covalent bonds. [•] UV irradiation leads to weak electrostatic interactions explaining the recovery of the NEA upon diamond annealing. [ABSTRACT FROM AUTHOR]

Abstract: Orange–red emitting NaSrBO3: Sm3+ phosphors were prepared by the combustion method using metal nitrates as precursors and urea as fuel. The particle sizes were in the range of 38–43nm. The monoclinic structure that is in good agreement with the standard NaSrBO3 was confirmed by X-ray diffraction. Scanning electron microscopy (SEM) indicated that an agglomerated peanut like morphology was obtained. UV–VIS spectrocsopy, photoluminescence (PL) and cathodoluminescence (CL) spectroscopy were utilized to investigate the spectral properties of the phosphor. The chemical states and the distribution of the dopants in the host were analysed with X-ray photoelectron spectroscopy (XPS) and time of flight-secondary ion mass spectroscopy (TOF-SIMS), respectively. Under the excitation of near UV light, NaSrBO3: Sm3+ exhibits the characteristic emissions resulting for the 4G5/2 → 6H x /2 (x =5, 7 and 9) transitions of Sm3+, with a maximum intensity at 599nm. In addition, the concentration of Sm3+ was varied in order to determine the optimum PL emission intensity. A maximum intensity was obtained from the sample with 2.0mol% of Sm3+. The potential applications of this phosphor, as a down conversion phosphor with an excitation wavelength of 395nm and good CL intensity, are evaluated for the possible use as a high-color-purity phosphor in light emitting diodes (LEDs) that can fill the 590–600nm gap and it may also be used as an amber color field emission display (FED) phosphor. [Copyright &y& Elsevier]

The increasing interest in phosphate glasses is due to the fact that they are considered to be bioactive functional materials in applications such as hard and soft tissue engineering and also that they possess interesting optical properties. These include low dispersion, high refractive index and high transparency for ultraviolet light. They have also been found to be responsible for the good anti-wear properties of phosphorus-based engine-oil additives. More recently, the low processing temperature of zinc and iron phosphates, as well as their chemical durability, has opened the possibility for new applications, such as the immobilization of nuclear wastes. Understanding the surface chemistry of such glasses turns out to be a key step for inferring their underlying mechanisms of action. In this work, zinc phosphate and iron phosphate glasses of different chain lengths were synthesized and characterized by means of time-of-flight secondary ion mass spectroscopy (ToF-SIMS). ToF-SIMS was able to successfully differentiate between the samples of different composition. A characteristic pattern of phosphate fragments was observed in the negative-mode ToF-SIMS spectra. The most intense peaks could be assigned to the phosphate fragments PO−, PO2−, PO3− and PO4−. Toward higher masses, fragments containing up to four phosphorus atoms with a periodicity of PO2 were observed: FePO3−, ZnPO3−, FePO4−, ZnPO4−, FeP2O6−, ZnP2O6−, FeP2O7−, ZnP2O7−; FeP3O8−, ZnP3O8−, FeP3O9− and ZnP3O9−. This pattern characterizes the spectra of all the glasses under investigation. For the first time, a method is proposed that allows the discrimination between polyphosphates of different chain lengths, by comparing the intensities of the relevant ToF-SIMS peaks. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The presence of polyoxymethylene (POM) in cometary grains has been debated years ago. Although never proven, its presence can not be excluded. Rosetta, the ESA mission to comet 67P/Churyumov–Gerasimenko, may answer this question. On board the spacecraft, COSIMA (COmetary Secondary Ion Mass Analyzer) will analyze the grains ejected from the nucleus using a Time Of Flight Secondary Ion Mass Spectrometer (TOF-SIMS). In this paper we report the extent to which COSIMA will be able to detect POM if this compound is present on cometary grains. We have analyzed two kinds of POM polymers with a laboratory model of COSIMA. Positive mass spectra display alternating sequence of peaks with a separation of 30.011Da between 1 and 600Da related to formaldehyde and its oligomers but also to the fragmentation of these oligomers. The separation of 30.011Da of numbers peaks, corresponding to the fragmentation into H2CO is characteristic of POM and we show that it could be highlight by mathematical treatment. POM lifetime on COSIMA targets have also been studied as POM is thermally instable. It can be concluded that the cometary grains analysis have to be planned not too long after their collection in order to maximize the chances to detect POM. This work was supported by the Centre National d''Etudes Spatiales (CNES). [Copyright &y& Elsevier]

Abstract: We present an ion beam study of the adsorption and the thermal stability of short alkanethiol molecules adsorbed on GaAs(110). Direct recoiling spectroscopy shows that the adsorption of ethanethiol and hexanethiol proceeds directly towards a dense standing up phase without passing through a stable phase of lying down molecules as is the case for Au(111). Measurements along specific azimuths suggest that both Ga and As rows are covered by the organic molecules. Short adsorption times from the vapor phase result in films having two desorption peaks near 300 and 500K. On the other hand, leaving the sample in a thiol atmosphere for several hours produces more stable films, similar to those produced by immersion in the corresponding thiol-ethanol solution. TOF-SIMS results confirm the C–S scission mechanism during the thermal desorption. [Copyright &y& Elsevier]

Abstract: High throughput materials discovery using combinatorial polymer microarrays to screen for new biomaterials with new and improved function is established as a powerful strategy. Here we combine this screening approach with high throughput surface characterization (HT-SC) to identify surface structure–function relationships. We explore how this combination can help to identify surface chemical moieties that control protein adsorption and subsequent cellular response. The adhesion of human embryoid body (hEB) cells to a large number (496) of different acrylate polymers synthesized in a microarray format is screened using a high throughput procedure. To determine the role of the polymer surface properties on hEB cell adhesion, detailed HT-SC of these acrylate polymers is carried out using time of flight secondary ion mass spectrometry (ToF SIMS), X-ray photoelectron spectroscopy (XPS), pico litre drop sessile water contact angle (WCA) measurement and atomic force microscopy (AFM). A structure–function relationship is identified between the ToF SIMS analysis of the surface chemistry after a fibronectin (Fn) pre-conditioning step and the cell adhesion to each spot using the multivariate analysis technique partial least squares (PLS) regression. Secondary ions indicative of the adsorbed Fn correlate with increased cell adhesion whereas glycol and other functionalities from the polymers are identified that reduce cell adhesion. Furthermore, a strong relationship between the ToF SIMS spectra of bare polymers and the cell adhesion to each spot is identified using PLS regression. This identifies a role for both the surface chemistry of the bare polymer and the pre-adsorbed Fn, as-represented in the ToF SIMS spectra, in controlling cellular adhesion. In contrast, no relationship is found between cell adhesion and wettability, surface roughness, elemental or functional surface composition. The correlation between ToF SIMS data of the surfaces and the cell adhesion demonstrates the ability to identify surface moieties that control protein adsorption and subsequent cell adhesion using ToF SIMS and multivariate analysis. [Copyright &y& Elsevier]

Abstract: A functionality of the novel black silicon based nanostructured surfaces (BS 2) with different metal surface modifications was tested by time-of-flight secondary ion mass spectrometry (TOF SIMS). Mainly two surface functions were studied: analytical signal enhancement and analyte pre-ionization effect in SIMS due to nanostructure type and the assistance of the noble metal surface coating (Ag or Au) for secondary ion formation. As a testing analyte a Rhodamine 6G was applied. Bi+ has been used as SIMS primary ions. It was found out that SIMS signal enhancement of the analyte significantly depends on Ag layer thickness and measured ion mode (negative, positive). The best SIMS signal enhancement was obtained at BS2 surface coated with 400nm of Ag layer. SIMS fragmentation schemes were developed for a model analyte deposited onto a silver and gold surface. Significant differences in pre-ionization effects can play an important role in the SIMS analysis due to identification and spectra interpretation. [Copyright &y& Elsevier]

Abstract: Parallel angle resolved X-ray photoelectron spectroscopy (ARXPS) was used to study the oxidation of W and WSi x thin films CVD-deposited on 12in. silicon wafers. The thin films were exposed to air during defined periods of time. Immediately after layer deposition, the wafers were rapidly loaded in a vacuum carrier in order to measure various aspects of the oxidation kinetic by XPS. Angle resolved data were exploited to obtain accurate tungsten oxide thicknesses measurements and the results were compared with X-ray reflectometry (XRR). A precise in-depth evolution of the W oxidation kinetic, in term of oxidation velocity and bonding environment, was obtained. Non-destructive profiles of the first five nanometers of a WSi x surface were extracted from Angle Resolved data. These profiles were compared to ToF-SIMS analysis, and we clearly show the presence of a stoichiometric silicon dioxide passive layer covering WSi x silicide. [Copyright &y& Elsevier]

Abstract: CO–NH3 ice at 25K is bombarded by 65MeV fission fragments and the emitted secondary ions are analyzed by time-of-flight mass spectrometry. The yields of the specific ion species (those formed only from CO or from NH3 molecules) and of the hybrid ion species (formed from both CO and NH3 molecules) are determined as a function of the ice temperature. The time-temperature dependence of desorption yields has been used for secondary ion identification because its behavior characterizes the ion''s origin around the sublimation temperature of CO ice (∼30K). The mass spectrum of positive ions measured before CO sublimation is decomposed into three spectra corresponding to CO specific ions, NH3 specific ions and hybrid molecular ions, respectively. The observed spectrum after CO sublimation is very similar to that of a pure NH3 specific spectrum. The total yield of all positive hybrid molecular ions over 600u mass range is found to be about 2 ions/impact: 20% of this is attributed to N and NH3 containing ions and 80% are ions having the C n O m Hl + structure. The ions C n≤3Hl,2,3 +, COH+, NO+, NH3OH+ and NH3CO+ were identified. At T =25K, the total yield of negative ions is about 20 times lower than that of positive ions, the most abundant species being the cyanide ion CN−. Observation of cluster ions based on (HCN) n indicates the formation of hydrogen cyanide. [Copyright &y& Elsevier]

Abstract: C60 ion beams are being used in a widening variety of analytical applications. The interaction of the C60 molecule with most sample surfaces differs markedly from that of an atomic ion beam, leading to elevated sputter yields and ion yields. A further important consequence of C60 bombardment is very low residual damage after sputtering of surface layers. We have developed a range of C60 ion beam systems for use in static SIMS, dynamic SIMS, SIMS imaging, including intracellular imaging of biological compounds, and in surface cleaning and depth profiling in electron spectroscopy. We describe the design criteria for the C60 range and illustrate the performance of these systems with recent applications data. [Copyright &y& Elsevier]

Abstract: Multivariate statistical methods such as principal components analysis (PCA) and factor analysis (FA) have been applied to mass spectral data to extract higher quality information from ion intensities in the mass spectrum. This often leads to better image quality in the resulting image analysis of principal components or factors. This paper presents a second multivariate statistical approach by examining the spatial statistics of the two dimensional image data. Geographic information is analyzed using two and three dimensional spatial statistical methods focused on interpolating spatial distributions. Methods such as Kriging and inverse squared distance weighting are often used to develop spatial distributions of common surface features distributed over geographic distances of meters, kilometers, miles, etc. Geospatial statistics have not been widely applied to spatial chemical distributions of microscopic dimensions. In this paper, we compare ordinary Kriging and inverse squared distance weighting for the analysis of ToF SIMS image data. By selectively eliminating pixels from the original image, we evaluate the accuracy of images reconstructed from 50 to 0.5% of the original dataset. Accurate image reconstruction from small datasets can provide added speed to ToF SIMS image collection and analysis, a potential advantage for on-line ToF SIMS analysis. [Copyright &y& Elsevier]

Abstract: This paper gives a critical review on the applications of ToF SIMS in the areas of polymer additive characterization and in the study of polymer blends and interfaces. Polymer additives can readily be identified by ToF SIMS using their parent molecular ions or characteristic fragments. This analytical capability has been successfully applied to monitor the migration or segregation of additives during polymer processing. ToF SIMS is an ideal analytical tool for the study of polymer blends and interfaces because it is able to provide information on both surface composition and morphology. In combination with other analytical techniques such as AFM and XPS, ToF SIMS chemical imaging capability has opened up new horizons in the investigation of complex polymer blend systems. Finally the main advantages and limitations of ToF SIMS in these application areas are also discussed. [Copyright &y& Elsevier]

Abstract: Frozen CO was bombarded by ∼65MeV fission fragments and the emitted secondary ions were analyzed by time-of-flight mass spectrometry. Target was kept at UHV conditions and its temperature was varied from 25K up to complete sublimation of the ice film. The observed positive cluster ion series are well represented by the chemical expression (CO) m C n +, where m and n ≥0, and the negative ones by C n − and (CO) m O−. The positive cluster ion series with the highest desorption yield is (CO)2C n +, in accordance with the particular high binding energy of (CO)2. The total negative ion yield is about 90 smaller than the positive one (2.8ions/impact) and the main negative ion series observed is C n −. The desorption yields of the cluster ion series decrease exponentially with the mass of the cluster, and it is proposed that the decay constant, k m, characterizes the process. The C n + and C n − series have a fast decay (k m =0.047u−1) and should be generated by fast gas-phase reactions in the thermalized nuclear track plasma. The (CO) m + series presents a slow decay constant (k m =0.007u−1); its members are probably residues of the fractured solid. Desorption yields depend weakly on target temperature up to near 30K, when fast sublimation occurs. Fullerene ions were not observed within Y(C40 +)≤2×10−4 ions/impact. [Copyright &y& Elsevier]

Experimental results on fast ion collision with icy surfaces having astrophysical interest are presented. 252Cf fission fragments projectiles were used to induce ejection of ionized material from H2O, CO2, CO, NH3, N2, O2 and Ar ices; the secondary ions were identified by time-of-flight mass spectrometry. It is observed that all the bombarded frozen gas targets emit cluster ions which have the structure XnR±, where X is the neutral ice molecule and R± is either an atomic or a molecular ion. The shape of the positive or negative ion mass spectra is characterized by a decreasing yield as the emitted ion mass increases and is generally described by the sum of two exponential functions. The positive ion water ice spectrum is dominated by the series (H2O)nH3O+ and the negative ion spectrum by the series (H2O)nOH− and (H2O)nO−. The positive ion CO2 ice spectrum is characterized by R+ = C+, O+, CO+, O2+ or CO2+ and the negative one by R− = CO3−. The dominant series for ammonia ice correspond to R+ = NH4+ and to R− = NH2−. The oxygen series are better described by (O3)nOm+ secondary ions where m = 1, 2 or 3. Two positive ion series exist for N2 ice: (N2)nN2+ and (N2)nN+. For argon positive secondary ions, only the (Ar)nAr+ series was observed. Most of the detected molecular ions were formed by one-step reactions. Ice temperature was varied from ∼20 K to complete sublimation. [ABSTRACT FROM AUTHOR]

Abstract: Secondary ion mass spectrometry is used to investigate ion emission from a frozen-gas mixture of CO2 and H2O (T =80–90K) bombarded by MeV nitrogen ions and by 252Cf fission fragments. The aim of the experiment is to detect organic molecules, produced in the highly excited material around the nuclear track, which appear as ions in the flux of sputtered particles. Part I of the present work [L.S. Farenzena, V.M. Collado, C.R Ponciano, E.F. da Silveira, K. Wien. Int. J. Mass Spectrom. 243 (2005) 85–93] described the method and presented the time-of-flight mass spectra; a list of the CO2 specific and H2O specific reaction products was provided. In Part II, the peaks of the TOF mass spectra are analyzed. Projectile-ice direct coulomb interaction leads to the production in the track of the H+, C+, O+, O2 +, CO+ and CO2 + primarily ions, which react in the highly energized nuclear track plasma mainly with CO2 and H2O or H2CO3. The positive molecular hybrid ions formed are identified as organic species like COH+, COOH+, CH n =1–3 +, H n =1,2COOH+ and cluster ions. Similarly, the negative primarily ions O− and OH− formed by electron capture produce negative hybrid ions such as (CO2) n OH−, the four ions (CO4H m =0–3)− and the corresponding cluster ions. By far, most of the molecular ions have been formed by one-step reactions; exceptions are eventually the CO4H m − ions created by a reaction between CO3 − and water molecules. An intense mass line corresponding to HCO3 + has been observed, but not the one due to formaldehyde ion. Weak signals of ionic ketene, hydrogen peroxide and carbonic acid were seen. [Copyright &y& Elsevier]

Abstract: Secondary ion mass spectrometry is used to investigate ion emission from a frozen-gas mixture (T =80–90K) of CO2 and H2O bombarded by MeV nitrogen ions and by 252Cf fission fragments (FF). The aim of the experiments is to produce organic molecules in the highly excited material around the nuclear track and to detect them in the flux of sputtered particles. Such sputter processes are known to occur at the icy surfaces of planetary or interstellar objects. Time-of-flight (TOF) mass spectrometry is employed to identify the desorbed ions. Mass spectra of positive and negative ions were taken for several molecular H2O/CO2 ratios. In special, positive ions induced by MeV nitrogen beam were analyzed for 9 and 18% H2O concentrations of the CO2–H2O ice and negative ions for ∼5% H2O. The ion peaks are separated to generate exclusive the spectra of CO2 specific ions, H2O specific ions and hybrid molecular ions, the latter ones corresponding to ions that contain mostly H and C atoms. In the mass range from 10 to 320u, the latter exhibits 35 positive and 58 negative ions. The total yield of the positive ions is 0.35 and 0.57 ions/impact, respectively, and of negative ions 0.066 ions/impact. Unexpected effects of secondary ion sputtering yields on H2O/CO2 ratio are attributed to the influence of water molecules concentration on the ionization process. [Copyright &y& Elsevier]

The analysis of doping element distribution in optical fiber cross sections requires a sensitive high spatial resolution technique. We demonstrate that a compact orthogonal Time-of-Flight (TOF) mass spectrometer attached to a multitechnique FIB-SEM-EDX system can be used to analyze cross sections of as manufactured optical fibers. By performing quantitative Energy Dispersive X-Ray (EDX) analysis of the optical preform, from which the fibers were drawn, we obtained conversion factors, which enabled the quantification of the Focused Ion Beam (FIB) SIMS profiles of the fiber cross sections. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The analyte signal enhancements of polymers and proteins were investigated using ionic liquid (IL) matrix-enhanced SIMS. The molecular weight of the polymer does not play a significant role in determining the magnitude of the n-mer and oligomer ion intensity enhancements. The analyte ion intensities enhancements are strongly dependent on the chemistry of the polymer side and terminal groups. Further, it was observed that ILs based on the matrix-assisted laser desorption/ionization matrix 2,5 dihydroxybenzoic acid were the most effective matrices. The molecular ion intensity enhancements of peptides including bradykinin were also investigated. Using bradykinins with different terminal amino acids, it is observed that molecular ion intensities are significantly enhanced using IL matrices if the N or C terminal amino acid can accept (or donate) a proton. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]