Secondary Ion Mass Spectrometry Research Papers (original) (raw)

2025, Physical Chemistry Chemical Physics

The interaction of the Li-ion battery solvent ethylene carbonate (EC) with Cu(111) was investigated by scanning tunnelling microscopy (STM) and variable temperature Xray photoelectron spectroscopy (XPS) under ultrahigh vacuum (UHV) conditions. Between 80 K and 420 K, the decomposition of EC goes along with distinct structural and chemical changes in the adlayer. The technological change from carbon based fossil energy fuels to renewable energy sources is the key for a sustainable energy system in the future. Sources like wind or solar energy are promising, but the energy generation is volatile and will result in temporal discrepancies between availability and demand. Consequently, highly efficient energy storage systems are urgently needed. 1 Meanwhile, the electrochemical energy storage in Lithium ion (Li-ion) batteries is indispensable for electronic devices, and due to their high energy density and long cycle life they are also promising candidates as power source for vehicles. 2,3 To improve the performance of Lithium ion batteries, much effort has been invested into the development of new electrode materials to improve energy density, charge/discharge rates, and lifetime. 4 In particular, studies have focussed on the solid-electrolyte interphase (SEI), which is formed on the surface of the electrode during the first operating cycle and mainly determines the batteries´ properties. It develops during the electrochemical reduction and subsequent decomposition of the organic solvent based electrolyte. Carbonates are the most frequently used solvents in commercial Li-ion batteries, with the electrolyte often being a mixture of ethylene carbonate (EC), propylene carbonate (PC), and linear carbonates, such as diethyl carbonate (DEC) or dimethylcarbonate (DMC), lithium salts, and other additives. Generally, it is challenging to derive a detailed understanding of the interactions and of the underlying mechanisms in multicomponent systems such as Li-ion batteries. Though numerous studies have been conducted in situ, in an electrochemical environment, details of the interaction of each component with the electrode, at the electrode|electrolyte interface, at a molecular level, are essentially unresolved. 6,7 Some insight was derived from spectroscopic studies. For example, Fourier transform infrared reflectance spectroscopy (FTIRS) 8 and Raman spectroscopy 9 were employed to probe the stability of carbonate solutions at different potentials. Very recently, Yu et al. observed an enrichment of EC on the surface of a LiCo 2 O electrode out of a 50

2025, npj Materials Degradation

Borosilicate glasses are currently used for the immobilization of highly radioactive waste and are materials of choice for many biomedical and research industries. They are metastable materials that corrode in aqueous solutions, reflected by the formation of silica-rich surface alteration layers (SAL). Until now, there is no consensus in the scientific community about the reaction and transport mechanism(s) and the rate-limiting steps involved in the formation of SALs. Here we report the results of multi-isotope tracer (2H,18O,10B, 30Si, 44Ca) corrosion experiments that were performed with precorroded and pristine glass monoliths prepared from the six-component international simple glass and a quaternary aluminum borosilicate glass. Results of transmission electron microscopy and nanoscale analyses by secondary ion mass spectrometry reveal a nanometer-sharp interface between the SAL and the glass, where decoupling of isotope tracer occurs, while proton diffusion and ion exchange can...

2025, Nanoscale Research Letters

We report on the use of the self-organization process of sputtered gold nanoparticles on a self-assembled block copolymer film deposited by horizontal precipitation Langmuir-Blodgett (HP-LB) method. The morphology and the phase-separation of a film of poly-n-butylacrylate-block-polyacrylic acid (Pn BuA-b-PAA) were studied at the nanometric scale by using atomic force microscopy (AFM) and Time of Flight Secondary Ion Mass Spectrometry (TOF-SIMS). The templating capability of the Pn BuA-b-PAA phase-separated film was studied by sputtering gold nanoparticles (NPs), forming a film of nanometric thickness. The effect of the polymer chain mobility onto the organization of gold nanoparticle layer was assessed by heating the obtained hybrid Pn BuA-b-PAA/Au NPs bilayer at T >Tg. The nanoparticles' distribution onto the different copolymer domains was found strongly affected by the annealing treatment, showing a peculiar memory effect, which modifies the AFM phase response of the Au NP...

2025

Correlative light and electron microscopy (CLEM) combines two imaging modalities, balancing out the limits of one technique with the other. In recent years, Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) has emerged as a flexible method that enables semi-automated volume acquisition at the ultrastructural level. We present a toolset for adherent cultured cells that enables tracking and finding cell regions previously identified in light microscopy, in the FIB-SEM along with automatic acquisition of high-resolution volume datasets. We detect a grid pattern in both modalities (LM and EM), which identifies common reference points. The novel combination of these techniques enables complete automation of the workflow. This includes setting the coincidence point of both ion and electron beams, automated evaluation of the image quality and constantly tracking the sample position with the microscope’s field of view reducing or even eliminating operator supervision. We show the abil...

2025, Journal of Volcanology and Geothermal Research

Fluid inclusions are rare in peralkaline granitoid xenoliths entrained in volcanic units at Pantelleria, Italy, suggesting that the shallow magma bodies in this peralkaline center do not develop extensive hydrothermal systems. Only one of the samples studied, an alkali-feldspar granite xenolith, contains abundant fluid inclusions in quartz. Four types of aqueous fluid inclusions are distinguished: Type I brines, including early, highly saline, NaCl-bearing inclusions (Th L= 508-560°C; salinity = 60-68 eq. wt.% NaCI) that occur in random groups (Type Ia) and late, NaCl-bearing inclusions (Th L = 386--450 ° C; salinity = 37-45 eq. wt.% NaC1) along secondary healed fractures (Type Ib); Type II vapor-rich aqueous inclusions ( Th v > 600 ° C) associated with Type Ia inclusions; Type III biphase ( L + V ) aqueous inclusions ( Th L = 360--390 ° C ) along secondary healed fractures; and minor Type IV high-density biphase (L+S) brines. The earliest fluids to be trapped (T> 600 °C) are represented by vapor-rich inclusions (Type II), which suggest boiling of the fluid phase. No coexisting brines were trapped, however, as all brines were trapped at temperatures below 560°C. High-salinity fluid phases circulated in the system down to temperatures of about 380 ° C, suggesting prolonged endogeneous fluid circulation in the shallow intrusive body that was the source for the xenolith. In contrast to the cooling history of many shallow-level granitic bodies, there is no evidence of pervasive circulation of low-temperature ( < 300°C), low-salinity fluids of largely meteoric origin.

2025, Science Advances

The Hayabusa2 spacecraft returned to Earth from the asteroid 162173 Ryugu on 6 December 2020. One day after the recovery, the gas species retained in the sample container were extracted and measured on-site and stored in gas collection bottles. The container gas consists of helium and neon with an extraterrestrial 3 He/ 4 He and 20 Ne/ 22 Ne ratios, along with some contaminant terrestrial atmospheric gases. A mixture of solar and Earth’s atmospheric gas is the best explanation for the container gas composition. Fragmentation of Ryugu grains within the sample container is discussed on the basis of the estimated amount of indigenous He and the size distribution of the recovered Ryugu grains. This is the first successful return of gas species from a near-Earth asteroid.

2025, BIOCELL

The 10 boron neutron-capture therapy (BNCT) is an emerging antitumoral method that shows increasing biomedical interest. BNCT is based on the selective accumulation of the 10 boron isotope within the tumor, which is then irradiated with low-energy thermal neutrons, generating nuclear fission that produces 7 lithium, 4 helium, and γ rays. Simple catechol-borate esters have been rather overlooked as precursors of melanin biosynthesis, and therefore, a proof-of-concept approach for using dopamine-borate (DABO) as a suitable boron-containing candidate for potential BNCT is presented here. DABO can spontaneously oxidize and autopolymerize in vitro, giving a soluble, eumelaninlike brown-black poly-DABO product. Melanotic melanoma cell cultures treated with 1 mM DABO for 24 and 48 h were viable and showed no signs of damage or cell death. The stability and possible trans-esterification of DABO is shortly discussed. Chemical calculations and quantitative structure-activity relationships (QSAR) analysis of DABO and the BNCT agent BPA indicated that they should be cell permeant and accumulate within lysosomes and melanosomes. Molecular modeling allows visualization of both the DABO precursor and the structure of a borate derivative of the proposed catechol-porphycene model for eumelanin, showing interesting features from molecular orbital calculations. The main difference between DABO and other agents, such as BPA, is that it is not a boronic acid nor a boron cluster. This simple catechol-borate ester (protected from oxidation and blackening) could be administrated to living cells and organisms, in which biosynthesis of boron-melanin in melanoma melanocytes can lead to improved BNCT.

2025, Acta Physica Polonica A

Thin layers of MgB x were studied in order to define evolution of superconducting phase after Mg ions implantation into boron substrate. Three fluencies of energies 140, 80, and 40 keV were used to establish proper stoichiometry to synthesize homogeneous MgB2 film. Additionally, the annealing processes were carried out at temperatures 400, 500, and 600 • C in a furnace in an atmosphere of flowing Ar-4%H 2 gas mixture. The quality of the superconducting material was examined by magnetically modulated microwave absorption, and magnetic and resistivity measurements. The results showed that Tc becomes higher with increasing annealing temperature. However, the fraction of superconducting phase decreases, due to partial evaporation of Mg ions and their deeper migration into boron substrate.

2025, Energy Procedia

In this work we investigate the potential of inline single side wet-etch processing for rear side emitter removal and edge isolation for large area p-type Passivated Emitter and Rear (PERC) silicon solar cells. We focus on the integration of this process in flows leading to shallow emitters and screen printed front contacts and to deep, highly ohmic emitters in association with Cu contacts. The inherent advantage of this process, beside high throughput, is the external gettering performed by full emitter etch at the rear side. This is particularly relevant in the case of two-step emitter formation process, where removal of phosphorus diffused layers is most effective when performed prior to the high temperature drive-in step. Another effect that we make use of is the front-side emitter etch back performed by the etch bath vapors, which can be used to tune the phosphorus surface concentration and thus the emitter sheet resistance. Using this process, we report efficiency up to 19.9% for CZ large-area, homogeneous-emitter, screen printed cells, and 20.4% for CZ, large-area Cu plated cells.

2025, Journal of The Electrochemical Society

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2025, Journal of Synchrotron Radiation

We have applied XAFS in order to determine both the chemical form and the place where heavy metals are stored in cultivated land snails. From Cu and Zn XANES spectra, the shells showed similar patterns as those of soft tissues and not like carbonates. This indicates that heavy metals are not completely taken into carbonate structures but are present within organic components in the shells. In addition, Cu XANES spectra of the samples showed low absorption edge-energy in the order of hepatopancreas, mantle, body, and shell. By comparing samples with standard reagents, each of which has only S- or O-ligand, it was found that the metals in hepatopancreas exist mostly as S-bound chemical components. To quantify the relative abundance of S-bound chemical component, partial least-squares (PLS) regression was applied. The PLS result indicated that for Cu, S-bound compound was higher in the order of hepatopancreas > mantle > body >shell.

2025, Tetsu-to-Hagane

To understand the effect of Fe 23 (C,B) 6 precipitation on hardenability of boron (B) added low carbon steels, we investigated the distribution of B at prior austenite grain boundaries by the advanced analysis using time-offlight secondary ion mass spectrometry (ToF-SIMS). The Mo-B combined steel which has no precipitation of Fe 23 (C,B) 6 showed flat intensity profiles of BO 2 ions at prior γ grain boundaries, while the B added steel showed the decrease in signal intensities of BO 2 -ions at the prior γ grain boundary between two Fe 23 (C,B) 6 precipitates. The results suggested that "solute B depleted zone" is formed near the precipitates and the Fe 23 (C,B) 6 precipitation promotes ferrite transformation not only by assisting itself but also by forming the solute B depleted zone.

2025, Geochimica et Cosmochimica Acta

2025, Journal of Applied Physics

The interface of zirconium oxide thin films on silicon is analyzed in detail for their potential applications in the microelectronics. The formation of an interfacial layer of ZrSixOy with graded Zr concentration is observed by the x-ray photoelectron spectroscopy and secondary ion mass spectrometry analysis. The as-deposited ZrO2/ZrSixOy/Si sample is thermally stable up to 880 °C, but is less stable compared to the ZrO2/SiO2/Si samples. Post-deposition annealing in oxygen or ammonia improved the thermal stability of as-deposited ZrO2/ZrSixOy/Si to 925 °C, likely due to the oxidation/nitridation of the interface. The as-deposited film had an equivalent oxide thickness of ∼1.3 nm with a dielectric constant of ∼21 and a leakage current of 3.2×10−3 A/cm2 at −1.5 V. Upon oxygen or ammonia annealing, the formation of SiOx and SiHxNyOz at the interface reduced the overall dielectric constants.

2025, Geochimica et Cosmochimica Acta

The partitioning of transition elements (Sc, Ti, V, Cr, Mn, Co, Ni) between orthopyroxene (opx) and clinopyroxene (cpx) in carefully selected garnet peridotite, spinel peridotite and garnet websterite xenoliths was determined by electron probe microanalyses (EPMA) and secondary ion mass spectrometry (SIMS). Xenoliths studied cover a wide compositional range and equilibrated under variable upper mantle conditions at temperatures between about 760 and 1370°C (two-pyroxene thermometer based on the enstatitediopside solvus) and pressures between about 0.8 and 3.6 GPa (Al-in-opx and Ca-in-olivine barometers). We found that the partitioning of transition elements between opx and cpx (expressed as D M ϭ concentration of element M in opx [cations per formula unit]/concentration of M in cpx [cations per formula unit]) is mainly controlled by temperature and to a much lesser degree by pressure. Variations in major element compositions of pyroxenes (e.g., variable X Mg , Al IV or Na) have no influence on D M . For Sc, V, Cr, Mn, and Co, our data result in good correlations between ln D M and reciprocal absolute temperature, with correlation coefficients (r) between 0.950 and 0.981. It is therefore possible to use the partitioning of these elements between opx and cpx from peridotites and websterites as geothermometers. On the basis of our data, we suggest the following empirical thermometer equations: where T is the absolute temperature in Kelvin and P the pressure in kilobars. For Ti and Ni observed correlations between ln D M and 1/T are less well defined.

2025, Boletín de la Sociedad Española de Cerámica y Vidrio

ZnO films were grown on sapphire (001) substrate by atmospheric MOCVD using diethyl zinc and tertiary butanol precursors. The influence of different carrier gases (H 2 and He) on the properties was analyzed by their structural (XRD), microstructural (SEM) and compositional (SIMS) characterization. The intensity of the strongest diffraction peak from ZnO (002) plane was increased by about 2 orders of magnitude when He is used as carrier gas, indicating the significant enhancement in crystallinity. The surface of the samples grown using H 2 and He carrier gases was composed of leaf-like and spherical grains respectively. Hydrogen [H] content in the film grown using H 2 is higher than that using He, indicating that the [H] was influenced by the H 2 carrier gas. Ultraviolet emission dominates the low temperature PL spectra. The emission from ZnO films grown using He show higher optical quality and more emission centers.

2025, Thin Solid Films

Nitrogen (N)-doped ZnO thin films were RF sputtered with different N 2 volume (ranging from 10% to 100%) on sapphire (001) substrates. The influence of N 2 vol.% on the properties of ZnO films was analyzed by various characterization techniques. The X-ray diffraction studies showed that the films grow along the preferential (002) crystallographic plane and the crystallinity varied with varying N 2 vol.%. The films sputtered with 25 vol.% N 2 showed better crystallinity. The transmittance was decreased with increasing N 2 volume until 25% and was almost constant above 25%. A maximum optical band gap (2.08 eV) obtained for 10 vol.% N 2 decreased with increasing N 2 volume to reach a minimum of 1.53 eV at 100%. The compositional analysis confirmed the incorporation of N into ZnO films, and its concentration increased with increasing N 2 volume to reach a maximum of ∼3.7 × 10 21 atom/cm 3 at 75% but then decreased slightly to 3.42 × 10 21 atoms/cm 3 . The sign of Hall coefficient confirmed that the films sputtered with ≤25 vol.% N 2 possess p-type conductivity which changes to n-type for N 25 vol.% N 2 .

2025, Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms

2025, Molecular Pharmaceutics

Objective: This study aimed to develop dry powder inhaler (DPI) combination formulations of ciprofloxacin and colistin for use in respiratory infections. Effects of colistin on physical stability and aerosolization of spray-dried ciprofloxacin were examined. The combination DPI formulations were produced by co-spray drying colistin and ciprofloxacin in mass ratios of 1:1, 1:3 and 1:9. Colistin and ciprofloxacin were also co-sprayed with L-leucine in the mass ratio of 1:1:1. The physical and aerosolization stability of the selected co-sprayed formulations stored at 20, 55 and 75% relative humidity (RH) were examined. Formulation characterizations were carried out using Powder X-ray diffraction (PXRD) for crystallinity, scanning electron microscopy (SEM) for morphology and particle size distribution, and Dynamic Vapor Sorption (DVS) for moisture sorption. Particle surface analysis was performed using X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray Spectrometry (EDX) and Nano-Time-of-flight Secondary Ion Mass Spectrometry (Nano ToF-SIMS). Potential intermolecular interactions were studied using Fourier-transform infrared spectroscopy (FTIR). Aerosol performance was evaluated using a multi-stage liquid impinger (MSLI) with a RS01 Monodose inhaler device. Results: PXRD diffractograms showed that the co-spray dried colistin-ciprofloxacin formulation in the mass ratio (1:1) was amorphous at 55% RH for up to 60 days; whereas the co-spray dried colistin-ciprofloxacin (1:3) and colistin-ciprofloxacin (1:9) crystallized after storage for 3 days at 55% RH. However, the extent of crystallization for the combination formulations was less as compared to the spray-dried ciprofloxacin alone formulation. Surface morphology of the co-spray dried formulations at different concentrations did not change even after storage at 55% RH for 60

2025, Molecular pharmaceutics

This study aimed to develop dry powder inhaler (DPI) combination formulations of ciprofloxacin and colistin for use in respiratory infections. Effects of colistin on physical stability and aerosolization of spray-dried ciprofloxacin were examined. The combination DPI formulations were produced by co-spray drying colistin and ciprofloxacin in mass ratios of 1:1, 1:3, and 1:9. Colistin and ciprofloxacin were also co-sprayed with l-leucine in the mass ratio of 1:1:1. The physical and aerosolization stability of the selected co-sprayed formulations stored at 20, 55, and 75% relative humidity (RH) were examined. Formulation characterizations were carried out using powder X-ray diffraction (PXRD) for crystallinity, scanning electron microscopy for morphology and particle size distribution, and dynamic vapor sorption for moisture sorption. Particle surface analysis was performed using X-ray photoelectron spectroscopy, energy dispersive X-ray spectrometry, and nano-time-of-flight secondary ...

2025, Analytical and Bioanalytical Chemistry

An on-line HPLC-ESI-MS-MS method has been developed for determination of glutathione and phytochelatins (PC) in plant tissues. For sample pretreatment, dithiothreitol (DTT) must be added at the very beginning, as an anti-oxidant. Optimization of instrumental conditions i.e. composition of HPLC mobile phase, ionization efficiency of the electrospray interface, and MS-MS detection in the multiple ionmonitoring mode, are the central aspects of this work. A polystyrene-packed column was found to be superior to a standard silica-packed reversed-phase column. A concave quadratic gradient of ammonium formate buffer and acetonitrile was found to be optimum. The limits of quantitation were 0.2 lmol kg À1 plant tissue for glutathione and PC. The method has been applied to analysis of tissue samples from Vicia faba grown in Cdcontaining nutrient solutions.

2025, Earth and Planetary Science Letters

The Trompsburg intrusion of South Africa is a large layered intrusion, measuring approximately 2500 km 2 . Little is known about its age and composition. Boreholes drilled in the 1940s to constrain a strong gravimetric and magnetic anomaly intersected up to 2 km of gabbro^troctolite^anorthosite containing up to 19 massive magnetite layers. Sr isotopic analyses performed in 1970 indicated an age of 1372 þ 142 Ma for the intrusion, suggesting no direct genetic link to the 2054 Ma Bushveld Complex. No further work was conducted on the Trompsburg intrusion during the last decades. Our results for a secondary ion mass spectrometry U/Pb isotope study on zircons from two gabbroic samples of the Trompsburg intrusion indicate a crystallisation age of 1915 þ 6 Ma, supporting the occurrence of a global 1.9 Ga superplume event. Using the new age, we recalculated available Sr isotope data. The results suggest that the Trompsburg intrusion has a lower crustal component than the Bushveld Complex, with Sr i approximately 0.704. A genetic relationship between the Trompsburg and Bushveld intrusions remains, therefore, unlikely.

2025, Analytical Chemistry

2025, Geochimica et Cosmochimica Acta

Results are reported from an experimental study in which the partitioning of U and Mg between aragonite and an aqueous solution were determined as a function of crystal growth rate. Crystals, identified as aragonite by X-ray diffractometry and micro-Raman spectroscopy, were grown by diffusion of CO 2 from an ammonium carbonate source into a calcium-bearing solution at temperatures of 22 and 53 °C. Hemispherical bundles (spherulites) of aragonite crystals were produced, the growth rates of which decreased monotonically from the spherulite interiors to the edges and thus provide the opportunity to examine the influence of growth rate on crystal composition. Element concentration ratios were measured using electron microprobe (EMP) and fluid composition was determined by inductively coupled plasma-mass spectrometry (ICP-MS) and atomic absorption (AA). Growth rates were determined directly by addition of a Dy spike to the fluid during the experiment that was subsequently located in an experimentally precipitated spherulite using secondary ion mass spectrometry (SIMS). At 22 °C both U/Ca and Mg/Ca partition coefficients exhibited a strong growth rate dependence when crystal growth rates were low, and became independent of growth rate when crystal growth rates were high. The U/Ca ratios in aragonite increase between 22 and 53 °C; in contrast Mg/Ca ratios show inverse dependence on temperature.

2025, Geochemistry, Geophysics, Geosystems

In situ secondary ion mass spectrometry (SIMS) analyses of d 7 Li, Li/Ca, and Mg/Ca were performed on five synthetic aragonite samples precipitated from seawater at 25°C at different rates. The compositions of d 7 Li in bulk aragonites and experimental fluids were measured by multicollector inductively coupled plasma-mass spectrometry (MC-ICP-MS). Both techniques yielded similar d 7 Li in aragonite when SIMS Copyright 2011 by the American Geophysical Union 1 of 16 analyses were corrected to calcium carbonate reference materials. Fractionation factors a 7 Li/ 6 Li range from 0.9895 to 0.9923, which translates to a fractionation between aragonite and fluid from -10.5‰ to -7.7‰. The within-sample d 7 Li range determined by SIMS is up to 27‰, exceeding the difference between bulk d 7 Li analyses of different aragonite precipitates. Moreover, the centers of aragonite hemispherical bundles (spherulites) are enriched in Li/Ca and Mg/Ca relative to spherulite fibers by up to factors of 2 and 8, respectively. The Li/Ca and Mg/Ca ratios of spherulite fibers increase with aragonite precipitation rate. These results suggest that precipitation rate is a potentially important consideration when using Li isotopes and elemental ratios in natural carbonates as a proxy for seawater composition and temperature.

2025, Meteoritics & Planetary Science

The petrography and mineral and bulk chemistries of silicate inclusions in Sombrerete, an ungrouped iron that is one of the most phosphate-rich meteorites known, was studied using optical, scanning electron microscopy (SEM), electron microprobe analysis (EMPA), and secondary ion mass spectrometry (SIMS) techniques. Inclusions contain variable proportions of alkalic siliceous glass (~69 vol% of inclusions on average), aluminous orthopyroxene (~9%, Wo 1-4 Fs 25-35 , up to ~3 wt% Al), plagioclase (~8%, mainly An 70-92 ), Cl-apatite (~7%), chromite (~4%), yagiite (~1%), phosphaterich segregations (~1%), ilmenite, and merrillite. Ytterbium and Sm anomalies are sometimes present in various phases (positive anomalies for phosphates, negative for glass and orthopyroxene), which possibly reflect phosphate-melt-gas partitioning under transient, reducing conditions at high temperatures. Phosphate-rich segregations and different alkalic glasses (K-rich and Na-rich) formed by two types of liquid immiscibility. Yagiite, a K-Mg silicate previously found in the Colomera (IIE) iron, appears to have formed as a late-stage crystallization product, possibly aided by Na-K liquid unmixing. Trace-element phase compositions reflect fractional crystallization of a single liquid composition that originated by low-degree (~4-8%) equilibrium partial melting of a chondritic precursor. Compositional differences between inclusions appear to have originated as a result of a "filter-press differentiation" process, in which liquidus crystals of Cl-apatite and orthopyroxene were less able than silicate melt to flow through the metallic host between inclusions. This process enabled a phosphoran basaltic andesite precursor liquid to differentiate within the metallic host, yielding a dacite composition for some inclusions. Solidification was relatively rapid, but not so fast as to prevent flow and immiscibility phenomena. Sombrerete originated near a cooling surface in the parent body during rapid, probably impact-induced, mixing of metallic and silicate liquids. We suggest that Sombrerete formed when a planetesimal undergoing endogenic differentiation was collisionally disrupted, possibly in a breakup and reassembly event. Simultaneous endogenic heating and impact processes may have widely affected silicate-bearing irons and other solar system matter. b "Na-glass" and "K-glass" counts include glass-rich mesostases that contain orthopyroxene crystallites and minor phosphate and plagioclase. c Average weighted by count area. d Includes Na-K-glass 17, 18, 6, 14) and Na-glass (other objects). e Plagioclase-glass intergrowths (spongy plagioclase). f P-rich segregations (phosphate-rich arcs and orb). g Mixed phase composed of an intergrowth of at least two phases, possibly Ti-oxide + pyroxene.

2025, Rapid Communications in Mass Spectrometry

The use of secondary ion mass spectrometry (SIMS) for the detection and spatially resolved analysis of individual high explosive particles is described. A C S 8 carbon cluster primary ion beam was used in a commercial SIMS instrument to analyze samples of high explosives dispersed as particles on silicon substrates. In comparison with monatomic primary ion bombardment, the carbon cluster primary ion beam was found to greatly enhance characteristic secondary ion signals from the explosive compounds while causing minimal beam-induced degradation. The resistance of these compounds to degradation under ion bombardment allows explosive particles to be analyzed under high primary ion dose bombardment (dynamic SIMS) conditions, facilitating the rapid acquisition of spatially resolved molecular information. The use of cluster SIMS combined with computer control of the sample stage position allows for the automated identification and counting of explosive particle distributions on silicon surfaces. This will be useful for characterizing the efficiency of transfer of particulates in trace explosive detection portal collectors and/or swipes utilized for ion mobility spectrometry applications. Published in 2006 by John Wiley & Sons, Ltd.

2025, Applied Surface Science

Cluster primary ion bombardment combined with secondary ion imaging is used on an ion microscope secondary ion mass spectrometer for the spatially resolved analysis of organic particles on various surfaces. Compared to the use of monoatomic primary ion beam bombardment, the use of a cluster primary ion beam (SF 5 þ or C 8 À ) provides significant improvement in molecular ion yields and a reduction in beam-induced degradation of the analyte molecules. These characteristics of cluster bombardment, along with automated sample stage control and custom image analysis software are utilized to rapidly characterize the spatial distribution of trace explosive particles, narcotics and inkjet-printed microarrays on a variety of surfaces.

2025, Analytical Chemistry

2025, Applied Surface Science

Secondary ion mass spectrometry (SIMS) employing an SF 5 + polyatomic primary ion source was used to depth profile through poly(methylmethacrylate) (PMMA), poly(lactic acid) (PLA) and polystyrene (PS) thin films at a series of temperatures from À125 8C to 150 8C. It was found that for PMMA, reduced temperature analysis produced depth profiles with increased secondary ion stability and reduced interfacial widths as compared to analysis at ambient temperature. Atomic force microscopy (AFM) images indicated that this improvement in interfacial width may be related to a decrease in sputter-induced topography. Depth profiling at higher temperatures was typically correlated with increased sputter rates. However, the improvements in interfacial widths and overall secondary ion stability were not as prevalent as was observed at low temperature. For PLA, improvements in signal intensities were observed at low temperatures, yet there was no significant change in secondary ion stability, interface widths or sputter rates. High temperatures yielded a significant decrease in secondary ion stability of the resulting profiles. PS films showed rapid degradation of characteristic secondary ion signals under all temperatures examined.

2025, The Journal of Physical Chemistry C

Cluster ion beams are being routinely utilized in secondary ion mass spectrometry (SIMS) for molecular depth profiling analyses, including the generation of three-dimensional data sets. Certain sample targets, such as soft organic matrices, often require large analysis ion fluences in order to generate sufficient count rates for pixel-to-pixel contrast. However, in the generation of this data during a SIMS dual-beam experiment, little attention has been given to the effects imparted into a depth-profiled sample merely by acquiring data between sputter erosion cycles. We find that the amount of Bi n + analysis fluence within a dual-beam sputter depth profiling experiment is not negligible and can degrade the interface widths of a high-quality PMMA film on silicon, despite the use of sputter beams such as SF 5 + and C 60 + to remove accumulated analysis beam-induced damage. These Bi n + fluence levels, which are often needed for generating enough counts in 3D molecular imaging experiments, can degrade the interface to the point where depth profiling information may not truly reflect the concentration of targeted molecules vs depth. This degradation is expected to worsen for multiple organic layer systems, where the accumulation of ion beam-induced damage can increase to levels where depth-resolved chemistry may not be achievable. † Part of the "Barbara J. Garrison Festschrift".

2025, Surface and Interface Analysis

Thin multilayer samples of Si/Ge, with individual layer thicknesses of 4–33 nm, have been analyzed by secondary ion mass spectrometry (SIMS) using Ar+, O2+ and Cs+ primary ion beams. Bombardment with both Ar+ and O2+ produced positive secondary ion depth profiles in which pronounced distortions were observed. Similar effects were found in negative secondary ion depth profiles with Cs+ bombardment. In each case, the SIMS depth profiles were characterized by abrupt interfacial secondary ion signal variations and a shift in the secondary ion signal maxima indicating that the layers were superposed, a condition that was not consistent with sample preparation, as verified by Auger electron spectroscopy. Auger electron spectroscopy depth profiling was also used to quantify the level of oxygen in the films. From these data it was concluded that the distortions in the positive secondary ion depth profiles under Ar+ bombardment were the result of secondary ion yield variations induced by enh...

2025, Surface and Interface Analysis

The dynamic range of SIMS depth profiles of high‐dose ion implants can often be improved by removing the influence of the highly doped crater walls from the depth profile. This is accomplished either by collapsing the primary beam raster or by using specialized sample preparation techniques such as the mini‐chip or dot‐etching methods developed by von Criegern et al. The main limitations with the sample preparation techniques are that they are labor and time‐intensive and are not applicable to all substrate types. By a simple modification of the raster circuits of an ion microscope, it is possible to generate, by sputtering, a mesa structure that is subsequently profiled under normal conditions. This approach offers a rapid, flexible method of mesa preparation that is amenable to all sample materials. The principal disadvantage with the use of the ion microscope for this analysis is that a significant memory effect can result from the dopant species that are sputtered during the pre...

2025, Metallurgical Transactions A

The compositional changes in A1-Li-(Mg)-(Cu) alloys induced by oxidation at high temperature (450 ~ to 570 ~ were investigated by secondary ion mass spectrometry (SIMS). It was found that the alloy surface beneath the oxide layer was depleted in both Li and Mg as a consequence of the selective oxidation of these elements, whereas Cu concentration was nearly constant or slightly increased in the affected zone. The measured-concentration profiles of Li and Mg were modeled using a diffusion equation to obtain diffusion data for the alloys. The depletion profiles also provided information regarding the interfacial-alloy composition and the depletion depth. The effect of alloying elements on the oxidation and depletion behavior is discussed. Secondary ion mass spectrometry data were quantified using the relative sensitivity factor method, and the quantification procedure is described in detail. K.K. SONI, Research Associate, is with the Enrico Fermi Institute,

2025, Forensic Science International

2025, Applied Surface Science

A C 60 + primary ion source has been coupled to an ion microscope secondary ion mass spectrometry (SIMS) instrument to examine sputtering of silicon with an emphasis on possible application of C 60 + depth profiling for high depth resolution SIMS analysis of silicon semiconductor materials. Unexpectedly, C 60 + SIMS depth profiling of silicon was found to be complicated by the deposition of an amorphous carbon layer which buries the silicon substrate. Sputtering of the silicon was observed only at the highest accessible beam energies (14.5 keV impact) or by using oxygen backfilling. C 60 + SIMS depth profiling of As delta-doped test samples at 14.5 keV demonstrated a substantial (factor of 5) degradation in depth resolution compared to Cs + SIMS depth profiling. This degradation is thought to result from the formation of an unusual platelet-like grain structure on the SIMS crater bottoms. Other unusual topographical features were also observed on silicon substrates after high primary ion dose C 60

2025, Applied Surface Science

2025, Analytical Chemistry

Sol-gel-derived SnO 2 and Fe 2 O 3 were selectively deposited on elements of micro hot plate (µHP) arrays. The silicon micromachined µHP arrays contain heating elements (100 µm × 100 µm) that are electronically addressable and thermally isolated from each other. Thin films of (tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane (TFS) or hexyltrichlorosilane (HFS) assembled on surfaces of the arrays served as thermally sensitive resists whereby heating of specific µHPs resulted in removal of organosilane films only in heated areas. TFS-masked surfaces were characterized with condensation figures and secondary ion mass spectrometry (SIMS) imaging. TFS was removed from regions heated above 400 °C to expose hydrophilic surfaces, while TFS films in unheated areas were unaffected and remained hydrophobic. Sol-gel tin oxide spin-coated on the thermally patterned arrays adhered only to the hydrophilic regions and was repelled from the hydrophobic areas masked by the TFS films. By using HFS films, it was possible to selectively deposit two sol-gel materials, SnO 2 and Fe 2 O 3 , on different µHPs in the same array as confirmed by SIMS imaging. Both materials showed varying degrees of electrical response to hydrogen and methanol in gas-sensing measurements.

2025, Rapid Communications in Mass Spectrometry

2025, Organic Mass Spectrometry

Organic compounds containing active hydrogens (e.g. imino, amino, carboxylic acid and hydroxy functional groups) undergo hydrogen–deuterium (H–D) exchange reactions in the course of argon ion bombardment in molecular secondary in mass spectrometry (SIMS) when examined as solids in solid ND4Cl matrix. The positive‐ion SIMS spectra of non‐ionic compounds (M) display ions resulting from exchange of active hydrogens in both the deuterated ((M + D)+) and cationized ((Ag + M)+ and (C+ + M)+) forms, while ionic compounds display exchange products in the intact cation (C+, where C = cation). Analogous H–D exchange is observed in the negative SIMS spectra of compounds bearing active hydrogen atoms. The fact that the exchange reactions are dependent on the primary ion dose demonstrates that they occur in the energized sample and not prior to ion bombardment. Information on the mechanisms of interfacial reactions, insights into the SIMS mechanism and confirmation of the number of acidic hydrog...

2025, The Japan Society of Applied Physics

1, はじめに InGaAs 系 HEMT はミリ波・サブミリ波帯でのキーデバイスとして注目されている。しかし、 InGaAs の狭いバンドギャップからデバイスの耐圧は低下する。これは、HEMT を用いて電力増幅器を構成した際の動作電圧を制限し、増幅器の出力や効率を高める上で不利である。我々はゲート電極に傾斜型フィールドプレート(FP)を導入し、デバイスのドレイン-ソース耐圧を高める手法を報告した [1]。しかし、耐圧は高くなったものの、電流利得遮断周波数(fT)は低下した。本発表では、FP を有する InGaAs 系 HEMT について遅延時間解析を行い、真性遅延時間から電子速度を抽出し、FP が電子走行に与える影響について報告する。 2, デバイス構造・測定結果・考察デバイス試作にはMOCVDにより成長した InAlAs/InGaAs HEMTエピタキシャル基板を用いた。ゲート電極には SiCN を用いて形成した FP を導入した [1]。SiCN 堆積時のキャリアガス流量を変化させることで、Fig. 1 に示すような 1-step、2-step、10-step の 3 種の FP を試作した。また、デバイスの高周波特性向上を目指して、InP エッチストップ層を Ar プラズマエッチングにより除去する二段階リセス構造 [2]も導入した。実ゲート長は集束イオンビーム(FIB)により測定した。真性遅延時間を[3]に示された手法により測定した。Fig. 2 に各 FP 構造によるゲート長(Lg)と真性遅延時間(τint)の結果を示す。外挿すれば原点を通る直線となり、実効電子速度を veffとした時の真性遅延時間の定義 τint=Lg/veffからも妥当といえる。FP 無しのものと比較し 10-step 型はほぼ同じ傾向であったのに対し、1-step 型と 2-step 型は真性遅延が大きく増加した。外挿の傾きの逆数から求めた電子速度 veffを Fig. 2 右側に示す。FP 無しと 10-step 型はともに理論値(2.5 x 10 7 cm/s)とほぼ等しい値となっているのに対し、1-step 型と 2-step 型は理論値から約 40%低い値となっていた。 FP導入による fT低下原因の 1つとして 1-step型と 2-s...

2025, Rapid Communications in Mass Spectrometry

2025, Journal of Crystal Growth

In GaAs/InGaP/GaAs structures grown by metal organic vapor-phase epitaxy (MOVPE), the two heterointerfaces are not identical. Normal photoluminescence (PL) features corresponding to the band gaps of GaAs and InGaP are seen for InGaP layer grown on GaAs. However, an intense long-wavelength feature is observed if we grow GaAs on InGaP (inverted structure) while the features of InGaP and GaAs are suppressed. The nature of interfacial regions is investigated by using di!erent gas switching sequences, which can in#uence the interfacial region composition. Signi"cantly, we "nd anomalous PL features similar to those observed in the case of inverted structure if we brie#y interrupt the growth of InGaP on GaAs and introduce AsH during the growth interruption. Secondary-ion mass spectrometry (SIMS) measurements and preliminary results of the compositional analysis of the interfacial layers based on high resolution X-ray di!raction (HRXRD) and PL measurements suggest that a deleterious e!ect arises with the exposure of InGaP surface to AsH and is attributed to the formation of an interfacial InGaAsP layer.

2025

Sub-micron, hollow organic globules reported from several carbonaceous chondrites, interplanetary dust particles, and comet Wild-2 samples returned by NASA?s Stardust mission are enriched in N-15/N-14 and D/H compared with terrestrial materials and the parent materials [1-4]. These anomalies are ascribed to the preservation of presolar cold molecular cloud material from where H, C, and N isotopic constraints point to chemical fractionation near 10 K [5]. An origin well beyond the planet forming region and their survival in meteorites suggests submicrometer organic globules were once prevalent throughout the solar nebula. The survival of the membrane structures indicates primitive meteorites and cometary dust particles would have delivered these organic precursors to the early Earth as well as other planets and satellites. The physical, chemical, and isotopic properties of the organic globules varies to its meteorite types and its lithologies. For example, organic globules in the Tag...

2025

 An IDP (a fragile-looking one)  Brownleeite TEM photo  Comet 26P/Grigg-Skjellerup (pretty sky photo; can do any comet if this specific one is too hard)  Comparison of some small world surfaces at same scales? Itokawa, 67P, Eros?  JSC sample curation facility (ideally, Keiko in her lab)  Hayabusa2 and OSIRIS-REx art [caption] Some IDPs are fragile, have primitive properties, and do not appear to be related to any meteorite. IDPs probably come from collisions among asteroids and from comet jets, but where any specific particle came from is unknown.

2025, Microscopy and Microanalysis

2025, Physics and Chemistry of Minerals

If carbon is to be analyzed by secondary ion mass spectroscopy (SIMS) in an oxide such as MgO, one has to know how the carbon is incorporated in the oxide host structure, before a successful experiment can be planned. If the carbon impurities derive from dissolved CO2 component which form a solid solution while the crystal grew from a melt in equilibrium with CO2, upon cooling, the solid solution becomes supersaturated with respect to the volatile CO2 component. This creates a thermodynamic driving force for exsolution leading to carbon segregation towards the surface. At the surface rapid degassing occurs in vacuum, enhanced by ion bombardment and electron irradiation. Using freshly cleaved synthetic MgO single crystals it can be shown by SIMS (i) that contamination during short exposure to air and during evacuation remains slight, (ii) that rapid surface/subsurface segregation of solute carbon seems to compete with rapid degassing so that, while no extended segregation profile builds up, the carbon concentration in the bulk beneath the surface decreases to a constant level, (iii) that electron irradiation speeds up degassing, (iv) that heating speeds up carbon diffusion, hence its segregation from the bulk, and (v) that Ar + ion sputtering for the purpose of removing possible contaminants reduces the driving force for carbon surface segregation to the point that no segregation profile can be observed. By placing freshly cleaved MgO crystals under isotopically 99 percent pure ~3CO2 for various periods of time subsequent SIMS analysis reveals extended z2C profiles, probably about 1 gm wide, which can only have formed by 12C segregation from the bulk. These results confirm earlier reports that solute carbon exists as mobile impurity in synthetic MgO and natural olivine, probably due to dissolved CO2 component.