Low Temperature Epitaxy Of Si/Si1-xGex/Si Multilayers By Low Pressure Rtcvd For Very Thin Soi Applications

1998 ◽  
Vol 533 ◽  
Author(s):  
D.W. McNeill ◽  
D.L. Gay ◽  
X. Lip ◽  
B.M. Armstrong ◽  
H.S. Gamble
Keyword(s):  
Scanning Probe Microscopy ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Vapour ◽  
High Growth ◽  
Silicon On Insulator ◽  
Ex Situ ◽  
Growth Time ◽  
Oxide Contamination ◽  
Secondary Ion

AbstractThe growth by rapid thermal chemical vapour deposition of Si/Si1-xGex/Si multilayer structures, suitable for thin bond and etch-back silicon-on-insulator fabrication has been investigated. Surface topography was studied by scanning probe microscopy, and layer contamination by secondary ion mass spectrometry. Smooth layers are only achieved at high growth temperatures (>700°C), and when surface oxide contamination is reduced by a combination of ex-situ HF vapour treatment and in-situ high temperature H2 bake. A surface peak-to-peak roughness of 15nm for a Si/Si1-xGex/Si multilayer structure has been achieved by reducing the growth time at 700°C or less. Further improvement is possible, especially if carbon contamination can be reduced.

Growth and study of BaZrO3 thin films by pulsed excimer laser ablation

2003 ◽  
Vol 784 ◽  
Author(s):  
V. Rajasekarakumar ◽  
P. Victor ◽  
R. Ranjith ◽  
S. Saha ◽  
S. Rajagopalan ◽  
...  
Keyword(s):  
Thin Films ◽  
Secondary Ion Mass Spectrometry ◽  
Ex Situ ◽  
Silicon Substrates ◽  
Frequency Regime ◽  
Different Temperatures ◽  
The Right ◽  
Limiting Case ◽  
Secondary Ion

ABSTRACTThin films of BaZrO3 (BZ) were grown using a pulsed laser deposition technique on platinum coated silicon substrates. Films showed a polycrystalline perovskite structure upon different annealing procedures of in-situ and ex-situ crystallization. The composition analyses were done using Energy dispersive X-ray analysis (EDAX) and Secondary ion mass spectrometry (SIMS). The SIMS analysis revealed that the ZrO2 formation at the right interface of substrate and the film leads the degradation of the device on the electrical properties in the case of ex-situ crystallized films. But the in-situ films exhibited no interfacial formation. The dielectric properties have been studied for the different temperatures in the frequency regime of 40 Hz to 100kHz. The response of the film to external ac stimuli was studied at different temperatures, and it showed that ac conductivity values in the limiting case are correspond to oxygen vacancy motion. The electrical modulus is fitted to a stretched exponential function and the results clearly indicate the presence of the non-Debye type of dielectric relaxation in these materials.

Optics-Free Visualization of Proteins in Single Cells by Time of Flight-Secondary Ion Mass Spectrometry Coupled with Genetically Encoded Chemical Tags

2020 ◽  
Author(s):  
Feifei Jia ◽  
Jie Wang ◽  
Yanyan Zhang ◽  
Qun Luo ◽  
Luyu Qi ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Single Cells ◽  
Time Of Flight ◽  
E Coli ◽  
Tof Sims ◽  
Ion Mass Spectrometry ◽  
Chemical Tags ◽  
Secondary Ion

<p></p><p><i>In situ</i> visualization of proteins of interest at single cell level is attractive in cell biology, molecular biology and biomedicine, which usually involves photon, electron or X-ray based imaging methods. Herein, we report an optics-free strategy that images a specific protein in single cells by time of flight-secondary ion mass spectrometry (ToF-SIMS) following genetic incorporation of fluorine-containing unnatural amino acids as a chemical tag into the protein via genetic code expansion technique. The method was developed and validated by imaging GFP in E. coli and human HeLa cancer cells, and then utilized to visualize the distribution of chemotaxis protein CheA in E. coli cells and the interaction between high mobility group box 1 protein and cisplatin damaged DNA in HeLa cells. The present work highlights the power of ToF-SIMS imaging combined with genetically encoded chemical tags for <i>in situ </i>visualization of proteins of interest as well as the interactions between proteins and drugs or drug damaged DNA in single cells.</p><p></p>

scholarly journals In Situ Correlative Microscopy Combining Transmission Electron Microscopy and Secondary Ion Mass Spectrometry

2018 ◽  
Vol 24 (S1) ◽  
pp. 380-381 ◽  
Author(s):  
Santhana Eswara ◽  
Lluis Yedra ◽  
Alisa Pshenova ◽  
Varun Sarbada ◽  
Jean-Nicolas Audinot ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mass Spectrometry ◽  
Transmission Electron Microscopy ◽  
Secondary Ion Mass Spectrometry ◽  
Correlative Microscopy ◽  
Transmission Electron ◽  
Ion Mass Spectrometry ◽  
Secondary Ion

scholarly journals Triple Oxygen Isotope Measurements by Multi-Collector Secondary Ion Mass Spectrometry

2021 ◽  
Vol 8 ◽  
Author(s):  
Nordine Bouden ◽  
Johan Villeneuve ◽  
Yves Marrocchi ◽  
Etienne Deloule ◽  
Evelyn Füri ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Oxygen Isotope ◽  
Spatial Resolution ◽  
Secondary Ion Mass Spectrometry ◽  
Small Radius ◽  
Large Radius ◽  
Ion Mass Spectrometry ◽  
Secondary Ion ◽  
Isotope Measurements

Secondary ion mass spectrometry (SIMS) is a powerful technique for in situ triple oxygen isotope measurements that has been used for more than 30 years. Since pioneering works performed on small-radius ion microprobes in the mid-80s, tremendous progress has been made in terms of analytical precision, spatial resolution and analysis duration. In this respect, the emergence in the mid-90s of the large-radius ion microprobe equipped with a multi-collector system (MC-SIMS) was a game changer. Further developments achieved on CAMECA MC-SIMS since then (e.g., stability of the electronics, enhanced transmission of secondary ions, automatic centering of the secondary ion beam, enhanced control of the magnetic field, 1012Ω resistor for the Faraday cup amplifiers) allow nowadays to routinely measure oxygen isotopic ratios (18O/16O and 17O/16O) in various matrices with a precision (internal error and reproducibility) better than 0.5‰ (2σ), a spatial resolution smaller than 10 µm and in a few minutes per analysis. This paper focuses on the application of the MC-SIMS technique to the in situ monitoring of mass-independent triple oxygen isotope variations.

Direct visualization of a vast cortical calcium compartment in Paramecium by secondary ion mass spectrometry (SIMS) microscopy: possible involvement in exocytosis

1995 ◽  
Vol 108 (5) ◽  
pp. 1895-1909 ◽  
Author(s):  
N. Stelly ◽  
S. Halpern ◽  
G. Nicolas ◽  
P. Fragu ◽  
A. Adoutte
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Membrane Vesicles ◽  
Cell Periphery ◽  
A Value ◽  
External Reference ◽  
Ion Mass Spectrometry ◽  
First Time ◽  
Secondary Ion

The plasma membrane of ciliates is underlaid by a vast continuous array of membrane vesicles known as cortical alveoli. Previous work had shown that a purified fraction of these vesicles actively pumps calcium, suggesting that alveoli may constitute a calcium-storage compartment. Here we provide direct confirmation of this hypothesis using in situ visualization of total cell calcium on sections of cryofixed and cryosubstituted cells analyzed by SIMS (secondary ion mass spectrometry) microscopy a method never previously applied to protists. A narrow, continuous, Ca-emitting zone located all along the cell periphery was observed on sections including the cortex. In contrast, Na and K were evenly distributed throughout the cell. Various controls confirmed that emission was from the alveoli, in particular, the emitting zone was still seen in mutants totally lacking trichocysts, the large exocytotic organelles docked at the cell surface, indicating that they make no major direct contribution to the emission. Calcium concentration within alveoli was quantified for the first time in SIMS microscopy using an external reference and was found to be in the range of 3 to 5 mM, a value similar to that for sarcoplasmic reticulum. After massive induction of trichocyst discharge, this concentration was found to decrease by about 50%, suggesting that the alveoli are the main source of the calcium involved in exocytosis.

The distribution and abundance of halogens in eclogites: An in situ SIMS perspective of the Raspas Complex (Ecuador)

2020 ◽  
Vol 105 (3) ◽  
pp. 307-318 ◽  
Author(s):  
Benjamin M. Urann ◽  
Véronique Le Roux ◽  
Timm John ◽  
Grace M. Beaudoin ◽  
Jaime D. Barnes
Keyword(s):  
Upper Mantle ◽  
Subduction Zones ◽  
Secondary Ion Mass Spectrometry ◽  
Bulk Rock ◽  
Ocean Island Basalts ◽  
High Pressure Metamorphism ◽  
Southern Ecuador ◽  
And Behavior ◽  
Secondary Ion

Abstract We present in situ secondary ion mass spectrometry (SIMS) and electron microprobe analyses of coexisting garnet, omphacite, phengite, amphibole, and apatite, combined with pyrohydrolysis bulk-rock analyses to constrain the distribution, abundance, and behavior of halogens (F and Cl) in six MORB-like eclogites from the Raspas Complex (Southern Ecuador). In all cases concerning lattice-hosted halogens, F compatibility decreases from apatite (1.47–3.25 wt%), to amphibole (563–4727 μg/g), phengite (610–1822 μg/g), omphacite (6.5–54.1 μg/g), and garnet (1.7–8.9 μg/g). The relative compatibility of Cl in the assemblage is greatest for apatite (192–515 μg/g), followed by amphibole (0.64–82.7 μg/g), phengite (1.2–2.1 μg/g), omphacite (&lt;0.05–1.0 μg/g), and garnet (&lt;0.05 μg/g). Congruence between SIMS-reconstructed F bulk abundances and yield-corrected bulk pyrohydrolysis analyses indicates that F is primarily hosted within the crystal lattice of eclogitic minerals. However, SIMS-reconstructed Cl abundances are a factor of five lower, on average, than pyrohydrolysis-derived bulk concentrations. This discrepancy results from the contribution of fluid inclusions, which may host at least 80% of the bulk rock Cl. The combination of SIMS and pyrohydrolysis is highly complementary. Whereas SIMS is well suited to determine bulk F abundances, pyrohydrolysis better quantifies bulk Cl concentrations, which include the contribution of fluid inclusion-hosted Cl. Raspas eclogites contain 145–258 μg/g F and at least 7–11 μg/g Cl. We estimate that ~95% of F is retained in the slab through eclogitization and returned to the upper mantle during subduction, whereas at least 95% of subducted Cl is removed from the rock by the time the slab equilibrates at eclogite facies conditions. Our calculations provide further evidence for the fractionation of F from Cl during high-pressure metamorphism in subduction zones. Although the HIMU (high U/Pb) mantle source (dehydrated oceanic crust) is often associated with enrichments in Cl/K and F/Nd, Raspas eclogites show relatively low halogen ratios identical within uncertainty to depleted MORB mantle (DMM). Thus, the observed halogen enrichments in HIMU ocean island basalts require either further fractionation during mantle processing or recycling of a halogen-enriched carrier lithology such as serpentinite into the mantle.

scholarly journals Development and Re‐Evaluation of Tourmaline Reference Materials for In Situ Measurement of Boron δ Values by Secondary Ion Mass Spectrometry

2020 ◽  
Vol 44 (3) ◽  
pp. 593-615 ◽  
Author(s):  
Katharina Marger ◽  
Matthieu Harlaux ◽  
Andrea Rielli ◽  
Lukas P. Baumgartner ◽  
Andrea Dini ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Reference Materials ◽  
Secondary Ion Mass Spectrometry ◽  
In Situ Measurement ◽  
Ion Mass Spectrometry ◽  
Secondary Ion

scholarly journals Hydrogen isotopic anomalies in extraterrestrial organic matter: role of cosmic ray irradiation and implications for UCAMMs

2019 ◽  
Vol 627 ◽  
pp. A122 ◽  
Author(s):  
B. Augé ◽  
E. Dartois ◽  
J. Duprat ◽  
C. Engrand ◽  
G. Slodzian ◽  
...  
Keyword(s):  
Organic Matter ◽  
Infrared Spectroscopy ◽  
Spatial Scale ◽  
Secondary Ion Mass Spectrometry ◽  
Isotopic Fractionation ◽  
Cosmic Ray ◽  
High Energy ◽  
Galactic Cosmic Rays ◽  
Ex Situ

Context. Micrometeorites represent, at timescales shorter than a few million years, the dominant source of extraterrestrial matter at the surface of the Earth. Analyses of ultracarbonaceous micrometeorites recovered from Antarctica, known as UCAMMs reveal an exceptionally N-rich organic matter associated with spatially extended high D enrichments. Experiments show that this specific organic matter might have been formed in the outer solar system by energetic irradiation of N-rich icy surfaces. Aims. We experimentally investigate the hydrogen isotopic fractionation resulting from irradiation of normal and D-rich N2-CH4 ices by high energy ions, simulating the exposition to Galactic cosmic rays of icy bodies surfaces orbiting at large heliocentric distances. Methods. Films of N2-CH4 ices and a N2-CH4/CD4/N2-CH4 “sandwich” ice were exposed to 129Xe13+ ion beams at 92 and 88 MeV. The chemical evolution of the samples was monitored using in situ Fourier transform infrared spectroscopy. After irradiation, targets were annealed to room temperature. The solid residues of the whole process left after ice sublimation were characterized in situ by infrared spectroscopy, and the hydrogen isotopic composition measured ex situ by imaging secondary ion mass spectrometry at the sub-micron scale (NanoSIMS). Results. Irradiation leads to the formation of new molecules and radicals. After annealing, the resulting poly-HCN-like macro-molecular residue exhibits an infrared spectrum close to that of UCAMMs. The residue resulting from irradiation of N2-CH4 ices does not exhibit a significant deuterium enrichment comparable to that found in extraterrestrial organic matter. The residue formed by irradiation of D-rich ices shows the formation of isotopic heterogeneities with localised hotspots and an extended contribution likely due to the diffusion of the radiolytic products from the D-rich layer. Conclusions. These results show that high-energy cosmic ray irradiation does not induce the large hydrogen isotopic fractionation observed at small spatial scale in interplanetary organics. By contrast, large D/H ratio heterogeneities at the sub-micron spatial scale in extraterrestrial organic matter can result from isotopically heterogeneous ices mixtures (i.e. condensed with different D/H ratios), which were transformed into refractory organic matter upon irradiation.

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