Ottawa, Canada
Ottawa, Canada

Time filter

Source Type

Fuchs S.H.J.,McGill University | Fuchs S.H.J.,Leibniz Institute of Marine Science | Schumann D.,Fibics Incorporated | Williams-Jones A.E.,McGill University | And 5 more authors.
Precambrian Research | Year: 2017

High-resolution scanning- and transmission-electron microscopy of pyrobitumen-hosted uraninite reveal that uraninite grains are highly porous aggregates of uniformly sized nanocrystals, and that many of their pores are filled by native gold. These texturally late gold grains, in turn, contain small pores occupied by former oil droplets that were converted to pyrobitumen during burial and metamorphism. The pyrobitumen in the pores of the gold grains contains in situ-formed uraninite nanocrystals. Galena also occupies the pores of the uraninite aggregates. In addition, this study reveals the first occurrence of rare lanarkite that engulfs the galena in the pores of the uraninite. On the basis of the nature of the uraninite and the filling of some of its pores with native gold, we propose a mineralization model for the deposition of the uranium and gold in the Carbon Leader Reef that calls upon the interaction of oil and aqueous (hydrothermal) fluids to form micro-emulsions. According to this model, uraninite nanocrystals precipitated from uranium-bearing hydrocarbon liquids and flocculated to form porous, uraninite aggregates. These liquids interacted with auriferous hydrothermal fluids in the Carbon Leader Reef, leading to the formation of a micro-emulsion at the interface between the two fluids. Gold precipitated as native metal around droplets of the oil owing to a reduction in oxygen fugacity, which destabilized the bisulfide species responsible for gold dissolution. Commonly, this process went hand in hand with the flocculation of the uraninite nanocrystals, causing entrapment of the native gold in the pores of the uraninite aggregates. The hydrocarbon liquid, which occurs as droplets in the gold and is the host to the uraninite aggregates, was transformed to pyrobitumen. As a result of this process, a thin pyrobitumen seam containing uraninite nanocrystals formed along the inner walls of the pores in the native gold. Lead introduced by the hydrocarbon liquid precipitated as galena. Interaction of the uraninite with hydrothermal fluids or radiolysis of the pore water facilitated the development of local zones of oxidation between galena and uraninite, which led to the crystallization of rare lanarkite. © 2017 Elsevier B.V.


Patent
Fibics Incorporated | Date: 2017-01-31

Notches or chevrons with known angles relative to each other are formed on a surface of the sample, where each branch of a chevron appears in a cross-sectional face of the sample as a distinct structure. Therefore, when imaging the cross-section face during the cross-sectioning operation, the distance between the identified structures allows unique identification of the position of the cross-section plane along the Z axis. Then a direct measurement of the actual position of each slice can be calculated, allowing for dynamic repositioning to account for drift in the plane of the sample and also dynamic adjustment of the forward advancement rate of the FIB to account for variations in the sample, microscope, microscope environment, etc. that contributes to drift. An additional result of this approach is the ability to dynamically calculate the actual thickness of each acquired slice as it is acquired.


England J.,Varian Semiconductor Equipment Associates | Phaneuf M.W.,Fibics Incorporated | Laquerre A.,Fibics Incorporated | Smith A.,University of Surrey | Gwilliam R.,University of Surrey
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2012

We have investigated ion beam assisted crystallization as a possible method for the creation of crystalline Si layers on amorphous substrates. Ion beam assisted crystallization has previously been characterised with pulsed and modest continuous beam current densities, but not at the high densities that would be required for high throughput processes. In this study, amorphous Si layers were implanted with Ga using a focused ion beam (FIB) tool and with Ga, Ar, Ge and As using beamline implanters. Crystallization was only observed for Ga, implying Ga alone was acting to reduce the activation energy. The observed rates of crystallization also implied that the relaxation state of the a-Si, influenced by the beam conditions, was an important driver for the phase transformation. © 2011 Elsevier B.V. All rights reserved.


Narayan K.,U.S. National Cancer Institute | Danielson C.M.,Northwestern University | Lagarec K.,Fibics Incorporated | Lowekamp B.C.,U.S. National Institutes of Health | And 5 more authors.
Journal of Structural Biology | Year: 2014

Efficient correlative imaging of small targets within large fields is a central problem in cell biology. Here, we demonstrate a series of technical advances in focused ion beam scanning electron microscopy (FIB-SEM) to address this issue. We report increases in the speed, robustness and automation of the process, and achieve consistent z slice thickness of ~3nm. We introduce "keyframe imaging" as a new approach to simultaneously image large fields of view and obtain high-resolution 3D images of targeted sub-volumes. We demonstrate application of these advances to image post-fusion cytoplasmic intermediates of the HIV core. Using fluorescently labeled cell membranes, proteins and HIV cores, we first produce a "target map" of an HIV infected cell by fluorescence microscopy. We then generate a correlated 3D EM volume of the entire cell as well as high-resolution 3D images of individual HIV cores, achieving correlative imaging across a volume scale of 109 in a single automated experimental run. © 2014.


PubMed | Fibics Incorporated, Northwestern University, U.S. National Institutes of Health and U.S. National Cancer Institute
Type: Journal Article | Journal: Journal of structural biology | Year: 2014

Efficient correlative imaging of small targets within large fields is a central problem in cell biology. Here, we demonstrate a series of technical advances in focused ion beam scanning electron microscopy (FIB-SEM) to address this issue. We report increases in the speed, robustness and automation of the process, and achieve consistent z slice thickness of 3 nm. We introduce keyframe imaging as a new approach to simultaneously image large fields of view and obtain high-resolution 3D images of targeted sub-volumes. We demonstrate application of these advances to image post-fusion cytoplasmic intermediates of the HIV core. Using fluorescently labeled cell membranes, proteins and HIV cores, we first produce a target map of an HIV infected cell by fluorescence microscopy. We then generate a correlated 3D EM volume of the entire cell as well as high-resolution 3D images of individual HIV cores, achieving correlative imaging across a volume scale of 10(9) in a single automated experimental run.


Thompson W.,Carl Zeiss GmbH | Stern L.,Carl Zeiss GmbH | Wu H.,Carl Zeiss GmbH | Ferranti D.,Carl Zeiss GmbH | And 5 more authors.
Conference Proceedings from the International Symposium for Testing and Failure Analysis | Year: 2012

Sub-nanometer focused inert gas ions derived from a Gas Field Ion Source (GFIS) contain properties that can improve the dimensional and conductivity characteristics of ion beam deposited platinum circuit edit wiring. The following paper, presents ion interaction simulations that help provide insight into the factors which determine the ultimate wire width, resistivity, and metal deposition rates. An experimental result that has aided in the understanding of the primary wire width limiting mechanism is also presented. Finally, a description of the ion beam and precursor properties used for the platinum deposition is provided, a long with a discussion of the wire resistivity measurement technique and challenges. To conclude, the prospects for GFIS ion induced dielectric and metal deposition for circuit edit and nanofabrication applications are discussed. Copyright © 2012 ASM International® All rights reserved.


Ronholm J.,University of Sainte-Anne | Schumann D.,University of Western Ontario | Schumann D.,Fibics Incorporated | Sapers H.M.,University of Sainte-Anne | And 8 more authors.
Geobiology | Year: 2014

Precipitation of calcium carbonate (CaCO3(s)) can be driven by microbial activity. Here, a systematic approach is used to identify the morphological and mineralogical characteristics of CaCO3(s) precipitated during the heterotrophic growth of micro-organisms isolated from polar environments. Focus was placed on establishing mineralogical features that are common in bioliths formed during heterotrophic activity, while in parallel identifying features that are specific to bioliths precipitated by certain microbial phylotypes. Twenty microbial isolates that precipitated macroscopic CaCO3(s) when grown on B4 media supplemented with calcium acetate or calcium citrate were identified. A multimethod approach, including scanning electron microscopy, high-resolution transmission electron microscopy, and micro-X-ray diffraction (μ-XRD), was used to characterize CaCO3(s) precipitates. Scanning and transmission electron microscopy showed that complete CaCO3(s) crystal encrustation of Arthrobacter sp. cells was common, while encrustation of Rhodococcus sp. cells did not occur. Several euhedral and anhedral mineral formations including disphenoid-like epitaxial plates, rhomboid-like aggregates with epitaxial rhombs, and spherulite aggregates were observed. While phylotype could not be linked to specific mineral formations, isolates tended to precipitate either euhedral or anhedral minerals, but not both. Three anhydrous CaCO3(s) polymorphs (calcite, aragonite, and vaterite) were identified by μ-XRD, and calcite and aragonite were also identified based on TEM lattice-fringe d value measurements. The presence of certain polymorphs was not indicative of biogenic origin, although several mineralogical features such as crystal-encrusted bacterial cells, or casts of bacterial cells embedded in mesocrystals are an indication of biogenic origin. In addition, some features such as the formation of vaterite and bacterial entombment appear to be linked to certain phylotypes. Identifying phylotypes consistent with certain mineralogical features is the first step toward discovering a link between these crystal features and the precise underlying molecular biology of the organism precipitating them. © 2014 John Wiley & Sons Ltd.


Fuchs S.,McGill University | Schumann D.,Fibics Incorporated | Schumann D.,University of Western Ontario | Williams-Jones A.E.,McGill University | Vali H.,McGill University
Chemical Geology | Year: 2015

Uranium and gold-bearing pyrobitumen from the Carbon Leader Reef in the Witwatersrand Basin, South Africa, was investigated by high-resolution transmission electron microscopy. This study provides evidence for the in-situ growth of uraninite and anatase nanocrystals in the pyrobitumen, implying mobilization and concentration of uranium and titanium by formerly mobile liquid hydrocarbons. Individual nanocrystals of uraninite and anatase are pervasively distributed and locally isolated within the pyrobitumen matrix. Crystallization of uraninite and anatase led to the formation of complex nanocrystal aggregates by oriented attachment, in which anatase generally provided nuclei for the growth of uraninite. Single nanocrystals of curite occur locally in channel ways within masses of uraninite nanocrystals, consistent with later auto-oxidation of uraninite and limited release of water during hydrocarbon maturation. On the basis of evidence for the migration of liquid hydrocarbons in the Witwatersrand Basin and the presence of abundant uraninite and anatase nanoparticles in pyrobitumen, a new model is proposed for the transport and concentration of uranium (and titanium) in the Carbon Leader Reef. According to this model, liquid hydrocarbons that were circulating in the Witwatersrand Basin dissolved detrital U-Ti-bearing minerals and transported the uranium and titanium until thermal degradation immobilized the hydrocarbons by solidifying them as pyrobitumen. The latter process involved the release of volatiles and the destruction of bonds that may have held the uranium and titanium in solution, thereby inducing the growth of individual uraninite and anatase nanocrystals and the formation of complex nanocrystal aggregates within the pyrobitumen. © 2014 Elsevier B.V.


An apparatus and method for using high beam currents in FIB circuit edit operations, without the generation of electrostatic discharge events. An internal partial chamber is disposed over the circuit to be worked on by the FIB. The partial chamber has top and bottom apertures for allowing the ion beam to pass through, and receives a gas through a gas delivery nozzle. A non-reactive gas, or a combination of a non-reactive gas and a reactive gas, is added to the FIB chamber via the partial chamber, until the chamber reaches a predetermined pressure. At the predetermined pressure, the gas pressure in the partial chamber will be much greater than that of the chamber, and will be sufficiently high such that the gas molecules will neutralize charging induced by the beam passing through the partial chamber.


Patent
Fibics Incorporated | Date: 2012-05-14

Generally, the present disclosure provides a method and system for improving imaging efficiency for CPB systems while maintaining or improving imaging accuracy over prior CPB systems. A large field of view image of a sample is acquired at a low resolution and thus, at high speed. The low resolution level is selected to be sufficient for an operator to visually identify structures or areas of interest on the low resolution image. The operator can select one or more small areas of arbitrary shape and size on the low resolution image, referred to as an exact region of interest (XROI). The outline of the XROI is mapped to an x-y coordinate system of the image, and the CPB system is then controlled to acquire a high resolution image of only the XROI identified on the low resolution image. For 3D imaging, once the XROI is identified, each section of the sample can be iteratively imaged in the previously described manner, with the operator having the option to redefine the XROI later.

Loading Fibics Incorporated collaborators
Loading Fibics Incorporated collaborators