scholarly journals Concept of Biogenic Ferromanganese Crust Formation: Coccoliths as Bio-seeds in Crusts from Central Atlantic Ocean (Senghor Seamount/Cape Verde)

2011 ◽  
Vol 6 (5) ◽  
pp. 1934578X1100600
Author(s):  
Xiaohong Wang ◽  
Florian Peine ◽  
Alexander Schmidt ◽  
Heinz C. Schröder ◽  
Matthias Wiens ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Deposition Process ◽  
Ferromanganese Crust ◽  
Cape Verde ◽  
Surface Zone ◽  
Ferromanganese Crusts ◽  
Central Atlantic ◽  
Scanning Electron

At depths of 2,000 to 3,000 m, seamounts from the Cape Verde archipelago (Central Atlantic Ocean) are largely covered with ferromanganese crusts. Here we studied 60 to 150 mm thick crusts from the Senghor Seamount (depth: 2257.4 m). The crusts have a non lamellated texture and are covered with spherical nodules. The chemical composition shows a dominance of MnO2 (26.1%) and Fe2O3 (38.8%) with considerable amounts of Co (0.74%) and TiO2 (2.1%). Analysis by scanning electron probe microanalyzer (EPMA) revealed a well defined compositional zonation of micro-layers; the distribution pattern of Mn does not match that of Fe. Analysis by high resolution scanning electron microscopy (SEM) revealed that coccospheres/coccoliths exist in the crust material as microfossils; most of the coccospheres/coccoliths are not intact. The almost circular coccoliths belong to the type of heterococcoliths and are taxonomically related to species of the family Calcidiscaceae. By energy dispersive X-ray spectroscopic analysis an accumulation of the coccoliths in the Mn- and Fe rich micronodules was detected. Focused ion beam assisted SEM mapping highlighted that the coccoliths in the crust are Mn rich, suggesting that the calcareous material of the algal skeleton has been replaced by Mn-minerals. We conclude that a biologically induced mechanism has been involved in the formation of the crusts, collected from the Cape Verde archipelago from depths of 2,000 to 3,000 m in the mixing region between the oxygen-minimum surface zone and the oxygen-rich deep waters; the deposition process might have been triggered by chemical reactions during the dissolution of the Ca-carbonate skeletons of the coccoliths allowing Mn(II) to oxidize to Mn(IV) and in turn to deposit this element in the crust material.

Electrical Characterization of Different Failure Modes in Sub-100 nm Devices Using Nanoprobing Technique

2009 ◽  
Author(s):  
E. Hendarto ◽  
S.L. Toh ◽  
J. Sudijono ◽  
P.K. Tan ◽  
H. Tan ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Focused Ion Beam ◽  
Failure Modes ◽  
Ion Beam ◽  
Electrical Characterization ◽  
Nickel Silicide ◽  
Fault Isolation ◽  
Technology Nodes ◽  
Scanning Electron

Abstract The scanning electron microscope (SEM) based nanoprobing technique has established itself as an indispensable failure analysis (FA) technique as technology nodes continue to shrink according to Moore's Law. Although it has its share of disadvantages, SEM-based nanoprobing is often preferred because of its advantages over other FA techniques such as focused ion beam in fault isolation. This paper presents the effectiveness of the nanoprobing technique in isolating nanoscale defects in three different cases in sub-100 nm devices: soft-fail defect caused by asymmetrical nickel silicide (NiSi) formation, hard-fail defect caused by abnormal NiSi formation leading to contact-poly short, and isolation of resistive contact in a large electrical test structure. Results suggest that the SEM based nanoprobing technique is particularly useful in identifying causes of soft-fails and plays a very important role in investigating the cause of hard-fails and improving device yield.

Focused Ion Beam Analysis of Low-K Dielectrics

2000 ◽  
Author(s):  
H. J. Bender ◽  
R. A. Donaton
Keyword(s):  
Electron Microscope ◽  
Cross Section ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Single Step ◽  
Specimen Preparation ◽  
Transmission Electron ◽  
Beam Analysis ◽  
Low K ◽  
Scanning Electron

Abstract The characteristics of an organic low-k dielectric during investigation by focused ion beam (FIB) are discussed for the different FIB application modes: cross-section imaging, specimen preparation for transmission electron microscopy, and via milling for device modification. It is shown that the material is more stable under the ion beam than under the electron beam in the scanning electron microscope (SEM) or in the transmission electron microscope (TEM). The milling of the material by H2O vapor assistance is strongly enhanced. Also by applying XeF2 etching an enhanced milling rate can be obtained so that both the polymer layer and the intermediate oxides can be etched in a single step.

FIB Enhancement of Mechanically Polished Cross-sections

2019 ◽  
Author(s):  
Becky Holdford
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Scanning Electron Microscope ◽  
Cross Sections ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
High Resolution Imaging ◽  
Chemical Attack ◽  
Resolution Imaging ◽  
Scanning Electron

Abstract On mechanically polished cross-sections, getting a surface adequate for high-resolution imaging is sometimes beyond the analyst’s ability, due to material smearing, chipping, polishing media chemical attack, etc.. A method has been developed to enable the focused ion beam (FIB) to re-face the section block and achieve a surface that can be imaged at high resolution in the scanning electron microscope (SEM).

Solving the Voltage Contrast on Floating Substrate with Standard FA Toolset

2016 ◽  
Author(s):  
Julien Goxe ◽  
Béatrice Vanhuffel ◽  
Marie Castignolles ◽  
Thomas Zirilli
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sample Preparation ◽  
Failure Analysis ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Silicon On Insulator ◽  
Mixed Signal ◽  
Voltage Contrast ◽  
Scanning Electron

Abstract Passive Voltage Contrast (PVC) in a Scanning Electron Microscope (SEM) or a Focused Ion Beam (FIB) is a key Failure Analysis (FA) technique to highlight a leaky gate. The introduction of Silicon On Insulator (SOI) substrate in our recent automotive analog mixed-signal technology highlighted a new challenge: the Bottom Oxide (BOX) layer, by isolating the Silicon Active Area from the bulk made PVC technique less effective in finding leaky MOSFET gates. A solution involving sample preparation performed with standard FA toolset is proposed to enhance PVC on SOI substrate.

Nanomechanical Characterization in the FIB

2005 ◽  
Author(s):  
Thomas M. Moore
Keyword(s):  
Focused Ion Beam ◽  
Ion Beam ◽  
Materials Characterization ◽  
Depth Of Focus ◽  
Ion Milling ◽  
Nano Technology ◽  
Physical Behavior ◽  
Nanomechanical Testing ◽  
Load Cells ◽  
Scanning Electron

Abstract The availability of the focused ion beam (FIB) microscope with its excellent imaging resolution, depth of focus and ion milling capability has made it an appealing platform for materials characterization at the sub-micron, or "nano" level. This article focuses on nanomechanical characterization in the FIB, which is an extension of the FIB capabilities into the realm of nano-technology. It presents examples that demonstrate the power and flexibility of nanomechanical testing in the FIB or scanning electron microscope with a probe shaft that includes a built-in strain gauge. Loads that range from grams to micrograms are achievable. Calibration is limited only by the availability of calibrated load cells in the smallest load ranges. Deflections in the range of a few nanometers range can be accurately applied. Simultaneous electrical, mechanical, and visual data can be combined to provide a revealing study of physical behavior of complex and dynamic nanostructures.

Degradation of a Metal–Polymer Interface Observed by Element-Specific Focused Ion Beam-Scanning Electron Microscopy

Langmuir ◽  
2020 ◽  
Vol 36 (11) ◽  
pp. 2816-2822 ◽  
Author(s):  
Takashi Kakubo ◽  
Katsunori Shimizu ◽  
Akemi Kumagai ◽  
Hiroaki Matsumoto ◽  
Miki Tsuchiya ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Beam Scanning ◽  
Polymer Interface ◽  
Metal Polymer ◽  
Scanning Electron

Optimized screen-printing and SEM-FIB characterization of YSZ thin films for Solid Oxide Fuel Cells and gas sensors devices

2004 ◽  
Vol 822 ◽  
Author(s):  
A. Morata ◽  
A. Tarancón ◽  
G. Dezanneau ◽  
F. Peiró ◽  
J. R. Morante
Keyword(s):  
Experimental Design ◽  
Screen Printing ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Deposition Process ◽  
Technological Parameters ◽  
Significant Information ◽  
Screen Printing Technique ◽  
Final Porosity

AbstractIn the present work, the screen printing technique has been used to deposit thick films of Zr0.84Y016O1.92 (8YSZ). In order to control the final porosity in view of a specific application (SOFCs or gas sensor), an experimental design based on analysis of variances (ANOVA) has been carried out. From this, we were able to determine the influence of several technological parameters on films porosity and grain size. The films obtained have been analysed with both Scanning Electron Microscopy (SEM) and Focused Ion Beam (FIB) combined with SEM. We show that only the combination of experimental design and advanced observation technique such as Focused Ion Beam allowed us to extract significant information for the improvement of the deposition process.

Focused ion beam scanning electron microscopy in biology

2014 ◽  
Vol 254 (3) ◽  
pp. 109-114 ◽  
Author(s):  
C. KIZILYAPRAK ◽  
J. DARASPE ◽  
B.M. HUMBEL
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Beam Scanning ◽  
Scanning Electron
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