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Secondary ion mass spectrometry (SIMS) is a very useful technique for the analysis of layered systems. It is based on the primary ion beam sputtering of solids and mass analysis of the emitted secondary ions. A main limitation of this technique results from the direct quantitative analysis, since the ionization efficiency of a given atom is highly influenced by the neighbouring atoms at the surface. This phenomenon is known as the 'matrix effect'. This problem can be partially solved by separation of the sputtering and ionization processes. The 'Storing Matter' technique involves deposition of the sputtered matter onto a rotating collector. Subsequently, ionisation occurs during the ion beam bombardment of the stored matter. In case of sputtering of a given layered structure, the stored matter deposit presents the sequence of the deposition process and the analysis of this deposit reflects the investigated structure. We analyse a set of on oxidized steel samples and oxidized steel covered by aluminium. These types of structures are known for strong matrix effects at the metal oxide interfaces. The results of the 'Storing Mater' analyses are compared with the results of the classical SIMS analysis. [ABSTRACT FROM AUTHOR]

Advantage of using individual dust meters over traditional stationary particulate matter (PM) air pollution monitoring is evaluated. Data of air pollution levels obtained from the three municipal stationary monitoring stations were compared with data of individual dust meters SidePak AM 510. Results of a few control series of this comparison have indicated important differences between the mentioned two types of synchronised measurements. Taking into account that vast majority of time people spend indoors, one may expect that individual samplers better characterise exposition of any human being on the PM urban pollution. As a result, a new sampling procedure is proposed. It allows the collection of particulate matter in the immediate vicinity of human being: As collectors of the PM, we propose mobile phones, accompanying people whatever is their everyday activity. Namely, dust deposited in the inner parts of the used mobile phones is extracted and analysed. The procedure consists of bulk analysis performed with spark source mass spectrometry (SSMS) and depth profile analysis made by secondary ion mass spectrometry (SIMS). Exemplary results are presented of the particulate material deposited on high purity indium foils. Ion erosion is done with 5 keV Ar+, 150-µm diameter ion beam scanned over 2 × 2.5 mm area. The analyser is equipped with Physical Electronics ion gun and QMA-410 Balzers quadrupole mass spectrometer. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Depth profile analysis in secondary ion mass spectrometry (SIMS) is applied for fly ash particles collected from three electrostatic precipitators in coal combustion type Thermoelectric Power Plant in Warsaw, Poland. Prior to analysis, particles of the collected material were size separated in nine stage cascade impactor with rotating substrate plates. Bulk analysis of the chosen size fractions was performed by atomic absorption spectroscopy. For SIMS depth profile analysis, particles were deposited on indium foils of high purity. Sputtering with 5 keV Ar+, 100 µm diameter ion beam was performed over 1.2 × 1.8 mm area of the indium foil in SIMS system (SAJW-05 model) equipped with Physical Electronics ion gun and QMA-410 Balzers quadrupole analyzer. SIMS data are quantified based on bulk concentration values of: carbon, sodium, aluminium, silicon, calcium, chromium, manganese, iron and nickel. Core-shell structure, and also cenosphere structure, is found. Depth profile analysis shows that shell layers of particles are enriched in carbon, calcium, chromium and nickel. Inner parts of particles or their cores are enriched in sodium and aluminium. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Two analytical techniques - secondary ion mass spectrometry (SIMS) and glow discharge mass spectrometry (GDMS) - were applied for depth profile analysis of ion-implanted nickel alloy inconel 600. Ion implantation with nitrogen, titanium, chromium and yttrium was performed in order to modify surface, mechanical and chemical properties. Implantation parameters were as follows: acceleration voltage 65 kV, ion fluence 1-2 mA/cm2. Series of ion implanted foils were then depth profiled using the two techniques applying ion sputtering. SIMS analysis was performed using 16 mm rods QMA-410 Balzers quadrupole mass spectrometer and Physical Electronics ion gun (3 keV Ar+ ion beam directed at 45 deg to the surface). GDMS analysis was done with 6 mm rods SRS-300 quadrupole spectrometer. Ion sputtering was performed due to glow discharge in ~0.1 Torr Ar with 1.5 kV DC voltage supplied to cathode (analysed sample). SIMS and GDMS data are quantified using internal standard method (main component elements) as well as ion implantation parameters. The two methods show similar distributions of ion-implanted species: N, Ti and Y. Also the depletion-enrichment of alloy components like Cr, Mn, Fe and Ni is observed in the 0-300 nm sputtering range using both methods. Nickel depletions, as well as chromium and manganese enrichments, are registered by both GDMS and SIMS. However, quantitation of these effects is difficult due to the strong mass interference of the polyatomic ions. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of magnesium diboride (MgB2), an intermetallic compound, possessing superconductive properties, were analysed by secondary ion mass spectrometry (SIMS). The samples were prepared using a new two-step technique of ion implantation followed by plasma treatment. Two kinds of structures were obtained when boron and magnesium were used as targets. Eighty kiloelectronvolt magnesium ions were implanted into boron samples and 100keV boron ions into magnesium strips. Plasma treatment was performed using hydrogen and argon 1μs plasma pulses of fluence 2–5J/cm2. Magnetic moment and electrical conductivity measurements confirmed superconducting properties of the obtained layers. SIMS depth profiling was performed using 5keV Ar+ ion beam (06-350E Physical Electronics) and quadrupole mass spectrometry (QMA 410 Balzers). Sensitivity factors for boron and magnesium were obtained based on SIMS analyses of bulk reference samples MgB2, B and Mg. Obtained results allow modifying technology parameters of thin film MgB2 synthesis. [Copyright &y& Elsevier]

Abstract: Urban aerosol particles were collected in two Polish towns—Legnica and Starachowice, and characterised with mass spectrometry methods. Bulk analysis of particulate matter collected on quartz fibre filters was performed using spark source mass spectrometry (SSMS). Analysis of chosen elements revealed the differences in total concentrations in the towns. We found in Legnica more: Sr—5 times with respect to Starachowice, Se, As—3 times, Cl, V, Y, Mo—2 times, Cr, Fe, Ni, Cu, Rb i Pb—less than 2 times. In Starachowice we found more: Ti—40 times, Zn—5 times, Mn—2 times, Br, Co i Zr—less than 2 times. Another technique—secondary ion mass spectrometry (SIMS) allowed us to perform depth profile analysis of collected particles on aluminium plates of cascade impactor. The SIMS results showed “core-shell” structure of particles dependent on their grain size in the range of 300nm to 15μm. The shell layer was enriched in Cr, Cu and Pb. The results were compared with the medical study of the prevalence of environmentally related children diseases observed in these two cities. Questionnaire studies and allergic skin prick tests were performed according to the protocol of International Study of Asthma and Allergies in Childhood (ISAAC). An epidemiological study performed on Legnica and Starachowice children shows statistically similar results besides the compositional and morphological differences of particles suspended in the air of the two towns. [Copyright &y& Elsevier]

Abstract: Ion beam sputtering of molecular beam epitaxy (MBE) grown laser heterostructures was performed in the secondary ion mass spectrometry (SIMS) depth profile analysis. The layered structures In0.24Al0.19Ga0.57As/Al0.25Ga0.75As/GaAs were bombarded with Ar+ ion beam of two energies 5000 and 880eV and several current densities. For the examined 4-μm-thick laser structures we obtained the depth profile resolution Δz 16–84%=7nm measured from the rising edge of indium peak during erosion of the indium reach layer in a waveguide region. The structures were bombarded with several incidence angles. Bombardment at 45° and 70° resulted in strange In+ secondary ion current oscillations registered at the SIMS profile when the sputtering front was passing single 8-nm-thick In0.24Al0.19Ga0.57As layer buried at a depth of 1.59μm. Ion bombardment at 20° allowed to avoid these oscillations. Secondary electron microscopy (SEM) images of the bombarded surfaces show the presence of several 3D objects including oval defects. We propose attributing these oscillation effects to primary ion beam shadowing by such objects. [Copyright &y& Elsevier]

Aerosol particles were collected in the vicinity of copper plants in Western Poland and analysed by mass spectrometry methods like secondary ion mass spectrometry (SIMS), spark source mass spectrometry (SSMS) and X-ray diffraction to characterise the possible dangers for the environment and health. The motivation of the work was to approach the toxicological mechanisms that are triggered when aerosol nanoparticles enter the human body. Different analytical techniques were used in order to compare bulk and surface properties of particles. The particle collection was performed with nine-stage cascade impactor with rotating plates and also with micro-fibre quartz filter collector. SSMS bulk analysis of copper plant emitted particles shows the presence of over 30 elements, the concentration in wt.% of Cu, Pb, Zn and Cl is 30, 5, 2 and 1, respectively. XRD analysis of these particles shows crystalline phases of quartz and probable phases containing copper CuS2, lead Pb2SiO4, PbO – massicot, Pb5[OH][PO4]3, Pb3SiO5, iron and calcium Ca[Mg0.67Fe0.33][CO3] – dolomite, ferroan, Ca[FeMg][CO3]2 – ankerite, Ca[MgFe]Si2O6 – augite. Surface sensitive SIMS depth profile analysis revealed the core-shell structure of copper plant emitted particles. The obtained structure of these particles shows that surfaces of the particles are enriched in elements like chlorine, fluorine, lead and chromium with respect to the core concentrations of these elements. The cores are composed mainly of copper, oxygen and carbon containing compounds. Lead concentration is nearly two times greater at the surface layers of particles than in the cores. SIMS analysis of urban aerosol particles collected in Legnica shows compositional dependence with size. Surface shell layer concentration of lead is three times greater for coarse 6–15 μm particles than for tiny 300 nm–1 μm particles. Such non-uniform particle morphology may enhance the toxic properties of particles suspended in air. [Copyright &y& Elsevier]

Welding fume particles were analyzed using low energy ion erosion in secondary ion mass spectrometry. The particles were collected during the welding process of steel performed with three different techniques: electron beam welding (EBW), gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW). The first process was performed in vacuum while the two others in atmosphere. A 300–400 nm diameter fraction of particles emitted in atmosphere was separated using a nine-stage impactor.Ion erosion of particles embedded in indium substrates was performed with 2 keV, 100 μm diameter, Ar+ ion beam at 45° ion incidence angle with respect to the substrate surface. The results show that all three types of particles have core–shell morphology. Particles formed in vacuum (EBW) have a shell enriched in oxygen, fluorine, chlorine, and potassium, with respect to the core composed mainly of iron, chromium and manganese. The GTAW particles are more oxidized than the EBW particles. Chlorine and fluorine dominate in the shell, however, their concentration in the core is higher than in the EBW particles. The SMAW particles are oxidized much more than two other types of particles. The shell is rich in chlorides, fluorides and potassium while the core is composed mainly of iron, chromium and manganese oxides. [Copyright &y& Elsevier]

Morphology of working environment nanoparticles was analyzed using sample rotation technique in secondary ion mass spectrometry (SIMS). The particles were collected with nine-stage vacuum impactor during gas tungsten arc welding (GTAW) process of stainless steel and shielded metal arc welding (SMAW) of mild steel. Ion erosion of 300–400 nm diameter nanoparticles attached to indium substrate was performed with 2 keV, 100 μm diameter, Ar+ ion beam at 45° ion incidence and 1 rpm sample rotation. The results show that both types of particles have core-shell morphology. A layer of fluorine, chlorine and carbon containing compounds covers stainless steel welding fume particles. The cores of these particles are enriched in iron, manganese and chromium. Outer shell of mild steel welding fume particles is enriched in carbon, potassium, chlorine and fluorine, while the deeper layers of these nanoparticles are richer in main steel components. [Copyright &y& Elsevier]