Pore Connectivity Characterization Using Coupled Wood’s Metal Intrusion and High-Resolution Imaging: A Case of the Silurian Longmaxi Shales From the Sichuan Basin, China

Pore connectivity is crucial for shale gas production. However, the three-dimensional (3D) characteristics and distribution of pore networks and, more fundamentally, the underlying role of different pore types on pore connectivity in shales are inadequately understood. By comparing the 3D pore connectivity derived from direct microstructural imaging of pores filled with Wood’s metal at a pressure corresponding to the finest accessible pore throat in the resolution ranges that may be achieved by X-ray micro-CT and SEM, it is possible to evaluate pore connectivity of different types of shales. The pore connectivity of three shales including a mixed mudstone, siliceous shale, and argillaceous shale from the Silurian Longmaxi Formations is investigated via combined broad ion beam (BIB) polishing, and SEM and X-ray micro-CT imaging after Wood’s metal injection at a pressure up to 380 MPa. The three shales show significant differences in pore connectivity. The mixed mudstone shows excellent pore connectivity in the matrix; the siliceous shale shows an overall poor connectivity with only a small amount of OM (organic matter) pores immediately adjacent to microfractures displaying interconnectivity, while the pores in the argillaceous shale, dominated by plate-like clay pores, are largely not interconnected.

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The Determination Of Diffusive Tortuosity In Concrete Specimens Using X-Ray Microtomography

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0140 ◽

2015 ◽

Vol 60 (2) ◽

pp. 1115-1119 ◽

Cited By ~ 9

Author(s):

Z. Ranachowski ◽

D. Jóźwiak-Niedźwiedzka ◽

P. Ranachowski ◽

M. Dąbrowski ◽

S. Kudela ◽

...

Keyword(s):

Random Walk ◽

Three Dimensional ◽

Micro Ct ◽

Connectivity Analysis ◽

Pore Connectivity ◽

Cement Ratio ◽

X Ray ◽

Water To Cement Ratio ◽

Random Walk Simulation

Abstract The paper presents a method of pore connectivity analysis applied to specimens of cement based composites differing in water to cement ratio. The method employed X-ray microtomography (micro-CT). Microtomography supplied digitized three-dimensional radiographs of small concrete specimens. The data derived from the radiographs were applied as an input into the application based on the algorithm called ‘random walk simulation’. As the result a parameter called diffusive tortuosity was established and compared with estimated porosity of examined specimens.

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3D Observation of Elemental Distribution of Si-Device using a Dedicated FIB/STEM System

ISTFA 2005: Conference Proceedings from the 31st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2005p0382 ◽

2005 ◽

Author(s):

T. Yaguchi ◽

M. Konno ◽

T. Kamino ◽

M. Ogasawara ◽

K. Kaji ◽

...

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Three Dimensional ◽

Elemental Distribution ◽

Multivariate Statistical ◽

X Ray ◽

Sample Rotation ◽

Transmission Electron ◽

Scanning Transmission ◽

Elemental Maps

Abstract A technique for preparation of a pillar shaped sample and its multi-directional observation of the sample using a focused ion beam (FIB) / scanning transmission electron microscopy (STEM) system has been developed. The system employs an FIB/STEM compatible sample rotation holder with a specially designed rotation mechanism, which allows the sample to be rotated 360 degrees [1-3]. This technique was used for the three dimensional (3D) elemental mapping of a contact plug of a Si device in 90 nm technology. A specimen containing a contact plug was shaped to a pillar sample with a cross section of 200 nm x 200 nm and a 5 um length. Elemental analysis was performed with a 200 kV HD-2300 STEM equipped with the EDAX genesis Energy dispersive X-ray spectroscopy (EDX) system. Spectrum imaging combined with multivariate statistical analysis (MSA) [4, 5] was used to enhance the weak X-ray signals of the doped area, which contain a low concentration of As-K. The distributions of elements, especially the dopant As, were successfully enhanced by MSA. The elemental maps were .. reconstructed from the maps.

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Multiscale microstructural characterization of Sn-rich alloys by three dimensional (3D) X-ray synchrotron tomography and focused ion beam (FIB) tomography

Materials Characterization ◽

10.1016/j.matchar.2012.05.004 ◽

2012 ◽

Vol 70 ◽

pp. 33-41 ◽

Cited By ~ 25

Author(s):

K.E. Yazzie ◽

J.J. Williams ◽

N.C. Phillips ◽

F. De Carlo ◽

N. Chawla

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Three Dimensional ◽

Microstructural Characterization ◽

X Ray ◽

Synchrotron Tomography

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Pore connectivity across scales and resolutions

10.5194/egusphere-egu2020-7588 ◽

2020 ◽

Author(s):

Maik Lucas ◽

Doris Vetterlein ◽

Hans-Jörg Vogel ◽

Steffen Schlüter

Keyword(s):

Characteristic Size ◽

Small Samples ◽

Pore Connectivity ◽

X Ray ◽

Connection Probability ◽

Three Samples ◽

Different Depths ◽

Pore Types ◽

First Time ◽

Joint Evaluation

An important parameter to quantify pore structure and link it to soil functions is connectivity. When quantifying connectivity with X-ray microtomography (X-ray-&#181;CT), one of the major drawbacks is that high resolution can only be achieved in small samples. In these samples, the small pores can be described, but the connectivity of larger pores cannot be quantified reasonably.Here we explore changes in pore connectivity with changing sample size covering a range of analyzed pore diameters of more than three orders of magnitude. Soil columns with a diameter of 10 cm were taken in two different depths (0 - 20 cm and 40 - 60 cm) at different sites of an agricultural chronosequence ranging in age from 0 to 24 years. X-ray CT was used for scanning the original columns as well as undisturbed subsamples of 3 and 0.7 cm diameter. This enabled us to detect characteristic traces in certain connectivity metrics on the chronosequence, caused by different pore types and thus different processes. In detail, we determined the connection probability of two random points within the pore system, i.e. the &#915;-indicator and the Euler number, &#967; as a function of minimum pore diameter.Our results revealed that scale artifacts in the connectivity functions overlap with characteristic signatures of certain pore types. For the very first time a new method for a joint-&#915;-curve was developed that merges information from three samples sizes, as the &#915;-indicator gives highly biased information in small samples. In contrast, &#967; does not require such a scale fusion and is helpful to define characteristic size ranges for pore types. Overall, findings suggest a joint evaluation of both connectivity metrics to identify the contribution of different pore types to the total pore connectivity with &#915; and to disentangle different pore types with &#967;.For the samples of the chronosequence such an evaluation revealed that biopores mainly connect pores of diameters between 0.1 and 0.5 mm. However, this was not necessarily coupled with increasing porosity. Tillage, conversely, lead to an increase in porosity due to a shift of pores of diameter >0.05 mm towards pores of diameter >0.20 mm and therefore increased connectivity of pores >0.20 mm.The current study is part of the DFG-Project Soil Structure (AOBJ: 628683).&#160;

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X-ray characterization of contact holes for block copolymer lithography

Journal of Applied Crystallography ◽

10.1107/s1600576718017272 ◽

2019 ◽

Vol 52 (1) ◽

pp. 106-114

Author(s):

Daniel F. Sunday ◽

Florian Delachat ◽

Ahmed Gharbi ◽

Guillaume Freychet ◽

Christopher D. Liman ◽

...

Keyword(s):

Self Assembly ◽

Low Cost ◽

Ion Beam ◽

Three Dimensional ◽

Incident Beam ◽

Residual Layer ◽

Processing Conditions ◽

Dimensional Metrology ◽

Grid Pattern ◽

X Ray

The directed self-assembly (DSA) of block copolymers (BCPs) is a promising low-cost approach to patterning structures with critical dimensions (CDs) which are smaller than can be achieved by traditional photolithography. The CD of contact holes can be reduced by assembling a cylindrical BCP inside a patterned template and utilizing the native size of the cylinder to dictate the reduced dimensions of the hole. This is a particularly promising application of the DSA technique, but in order for this technology to be realized there is a need for three-dimensional metrology of the internal structure of the patterned BCP in order to understand how template properties and processing conditions impact BCP assembly. This is a particularly challenging problem for traditional metrologies owing to the three-dimensional nature of the structure and the buried features. By utilizing small-angle X-ray scattering and changing the angle between the incident beam and sample we can reconstruct the three-dimensional shape profile of the empty template and the residual polymer after self-assembly and removal of one of the phases. A two-dimensional square grid pattern of the holes results in scattering in both in-plane directions, which is simplified by converting to a radial geometry. The shape is then determined by simulating the scattering from a model and iterating that model until the simulated and experimental scattering profiles show a satisfactory match. Samples with two different processing conditions are characterized in order to demonstrate the ability of the technique to evaluate critical features such as residual layer thickness and sidewall height. It was found that the samples had residual layer thicknesses of 15.9 ± 3.2 nm and 4.5 ± 2.2 nm, which were clearly distinguished between the two different DSA processes and in good agreement with focused ion beam scanning transmission electron microscopy (FIBSTEM) observations. The advantage of the X-ray measurements is that FIBSTEM characterizes around ten holes, while there are of the order of 800 000 holes illuminated by the X-ray beam.

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Atomic Layer Deposition of Superconducting CuO Thin Films on Three-Dimensional Substrates

Crystals ◽

10.3390/cryst10080650 ◽

2020 ◽

Vol 10 (8) ◽

pp. 650

Author(s):

Aile Tamm ◽

Aivar Tarre ◽

Valeriy Verchenko ◽

Helina Seemen ◽

Raivo Stern

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

Ion Beam ◽

Three Dimensional ◽

Atomic Layer ◽

Deposition Process ◽

Critical Temperatures ◽

Organic Precursor ◽

X Ray ◽

Layer Deposition

In previous decades, investigation of superconductors was aimed either at finding materials with higher critical temperatures or at discovering nontypical superconducting behavior. Here, we present the cupric (CuO) thin films, which were synthesized by atomic layer deposition by using a metal-organic precursor, copper (II)-bis-(-dimethylamino-2-propoxide), and ozone as an oxidizer. The deposition process was optimized by employing a quartz crystal monitoring, and the contact between the deposited films and planar and three-dimensional SiO2/Si substrates was examined by scanning electron microscopy with a focused ion beam module. Phase and elemental composition were analyzed by X-ray diffraction and X-ray fluorescence. Two-probe electrical resistivity measurements revealed a resistivity drop below the critical temperature of 4 K, which may indicate low-temperature superconductivity of the CuO thin films.

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Comprehensive multilayer film analysis with XPS, AES, and EDS

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133552 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1784-1785

Author(s):

N. C. Miller

Keyword(s):

Photoelectron Spectroscopy ◽

Secondary Ion Mass Spectrometry ◽

Surface Composition ◽

Ion Beam ◽

Three Dimensional ◽

Chemical Mapping ◽

Vertical Diffusion ◽

X Ray ◽

Sample Rotation ◽

Microscopic Features

Wavelength and energy dispersive x-ray spectroscopy (WDS and EDS) are routinely utilized to measure qualitatively and quantitatively the composition of microscopic features/phases of thickness 0.5 (μm or greater in solids. Surface spectroscopies, especially x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES), are employed to determine surface chemistry and surface composition respectively of microscopic features 0.2-5 nm thick. The combined utilization of AES and EDS (or WDS) permits microanalysis of surface and subsurface features/phases. Two areas of improved analysis through combined utilization of AES and EDS are imaging/elemental mapping and measurement of vertical diffusion profiles. Strengths of XPS in complementing EDS/WDS will also be discussed.High resolution surface elemental or chemical mapping can be carried out with scanning Auger or secondary ion mass spectrometry (SIMS) microanalysis, respectively. In fact, both offer improved spacial resolution over WDS and EDS elemental x-ray dot mapping. Using sample rotation while removing material by ion beam sputter etching, three dimensional mapping can be carried out by either surface analysis technique, permitting microanalysis of buried features even in complex heterostructures.

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Three-Dimensional Analysis of Carbon Nanotube Networks in Interconnects by Electron Tomography without Missing Wedge Artifacts

Microscopy and Microanalysis ◽

10.1017/s1431927609991371 ◽

2010 ◽

Vol 16 (2) ◽

pp. 210-217 ◽

Cited By ~ 41

Author(s):

Xiaoxing Ke ◽

Sara Bals ◽

Daire Cott ◽

Thomas Hantschel ◽

Hugo Bender ◽

...

Keyword(s):

Focused Ion Beam ◽

Electron Tomography ◽

Ion Beam ◽

Full Range ◽

Three Dimensional ◽

X Ray ◽

Quantitative Studies ◽

Transmission Electron ◽

Carbon Nanotube Networks ◽

Semiconductor Contact

AbstractThe three-dimensional (3D) distribution of carbon nanotubes (CNTs) grown inside semiconductor contact holes is studied by electron tomography. The use of a specialized tomography holder results in an angular tilt range of ±90°, which means that the so-called “missing wedge” is absent. The transmission electron microscopy (TEM) sample for this purpose consists of a micropillar that is prepared by a dedicated procedure using the focused ion beam (FIB) but keeping the CNTs intact. The 3D results are combined with energy dispersive X-ray spectroscopy (EDS) to study the relation between the CNTs and the catalyst particles used during their growth. The reconstruction, based on the full range of tilt angles, is compared with a reconstruction where a missing wedge is present. This clearly illustates that the missing wedge will lead to an unreliable interpretation and will limit quantitative studies.

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