Depth Profiling with Ion Induced X-Rays

1976 ◽  
pp. 735-745 ◽  
Author(s):  
L. C. Feldman ◽  
P. J. Silverman
Keyword(s):  
Depth Profiling ◽  
X Rays

Depth Sensitive Imaging of Defects in Epilayers and Single Crystals Using White Beam Synchrotron Radiation Topography in Grazing Bragg-Laue Geometry.

1989 ◽  
Vol 163 ◽  
Author(s):  
M. Dudley ◽  
G.-D. Yao ◽  
J. Wu ◽  
H.-Y. Liu
Keyword(s):  
Penetration Depth ◽  
Depth Profiling ◽  
X Rays ◽  
X Ray Diffraction ◽  
General Applicability ◽  
Advantages And Disadvantages ◽  
White Beam ◽  
Diffraction Geometry ◽  
Topographic Imaging

AbstractThe technique of Synchrotron White Beam topographic imaging in grazing Bragg-Laue geometries has been developed at the Stony Brook synchrotron topography station at the NSLS. This technique enables imaging of defects in subsurface regions of thickness which can range from hundreds of Angstroms to hundreds of microns as determined by the penetration depth of the X-rays. This penetration depth, which is shown to be determined by the kinematical theory of X-ray diffraction, can be conveniently varied, in a controlled manner, by simple manipulation of the diffraction geometry, thereby enabling a depth profiling of the defect content.The fundamentals of the technique are described, and its advantages and disadvantages compared to existing techniques are discussed in detail. Examples of application of the technique in the characterization of defects in thin epitaxial films of GaAs on Si, are given, and the general applicability of the technique is discussed.

Angle-Resolved X-Ray Depth Profiling: Interpretation of Angleresolved Profiles Using a Monte Carlo Approach

1999 ◽  
Vol 5 (S2) ◽  
pp. 582-583
Author(s):  
D.K. Wilkinson ◽  
M. Prutton ◽  
D.A. Loveday
Keyword(s):  
Monte Carlo ◽  
Electron Scattering ◽  
Photoelectron Spectroscopy ◽  
Depth Profiling ◽  
Incident Beam ◽  
Angle Of Incidence ◽  
X Rays ◽  
X Ray ◽  
Interaction Volume ◽  
Depth Profiles

A technique has been developed for the interpretation of composition depth profiles from angleresolved x-ray data using a Monte Carlo electron scattering simulation. Conventional methods for the interpretation of angle-resolved depth profiles used in the fields of x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) assume that the outgoing signal is exponentially attenuated along its path. This assumption if not valid for angle-resolved x-ray techniques, as the x-ray signal is dependent on both the paths of the incident electrons and the path of the emitted x-rays. In this case, while the latter can be treated using an exponential attenuation, the path of the incident beam is more complex and corresponds to the well known “pear-shaped” interaction volume. In order to reliably interpret angle-resolved depth profiles in which the angle of the incident beam is varied, it is necessary to be able to obtain the distribution of x-ray emission within the sample for any angle of incidence.

Depth profiling by XFA with selective excitation and variation of incidence and take-off angle of x-rays

1993 ◽  
Vol 22 (4) ◽  
pp. 305-311 ◽  
Author(s):  
H. Ebel ◽  
M. F. Ebel ◽  
R. Svagera ◽  
M. Heller ◽  
C. Pöhn ◽  
...  
Keyword(s):  
Depth Profiling ◽  
Selective Excitation ◽  
X Rays

Confocal X-ray Fluorescence (XRF) Microscopy: A New Technique for the Nondestructive Compositional Depth Profiling of Paintings

2004 ◽  
Vol 852 ◽  
Author(s):  
Arthur R. Woll ◽  
Donald H. Bilderback ◽  
Sol Gruner ◽  
Ning Gao ◽  
Rong Huang ◽  
...  
Keyword(s):  
Depth Profiling ◽  
Incident Beam ◽  
High Energy ◽  
X Rays ◽  
Oil Painting ◽  
Synchrotron Source ◽  
X Ray ◽  
Glass Slides ◽  
A New Technique ◽  
Paint Films

ABSTRACTA confocal x-ray fluorescence microscope was built at the Cornell High Energy Synchrotron Source (CHESS) to determine the composition of buried paint layers that range from 10–80 μm thick in paintings. The microscope consists of a borosilicate monocapillary optic to focus the incident beam and a borosilicate polycapillary lens to collect the fluorescent x-rays. The overlap of the two focal regions is several tens of microns in extent, and defines the active, or confocal, volume of the microscope. The capabilities of the technique were tested using acrylic paint films with distinct layers brushed onto glass slides and a twentieth century oil painting on canvas. The position and thickness of individual layers were extracted from their fluorescence profiles by fitting to a simple, semi-empirical model.

Spatially Resolved Energy Dispersive X-Ray Diffraction (EDXRD) as a Tool for Nondestructively Providing Phase Composition Depth Profiles on Cement and Other Materials

2004 ◽  
Author(s):  
Angus P. Wilkinson ◽  
Andrew C. Jupe ◽  
Kimberly E. Kurtis ◽  
Nikhila N. Naik ◽  
Stuart R. Stock ◽  
...  
Keyword(s):  
Phase Composition ◽  
Depth Profiling ◽  
Sample Surface ◽  
High Energy ◽  
Energy Dispersive ◽  
X Rays ◽  
Portland Cement Concrete ◽  
Depth Profiles ◽  
Spatially Resolved ◽  
Wide Range

The presence of sulfates in water or soils surrounding portland cement concrete structures leads to progressive degradation. Spatially resolved energy dispersive diffraction (EDXRD) in combination with computed microtomography (μCT) and mechanical measurements can provide the information needed to understand, in detail, the degradation mechanisms that are associated with sulfate attack and to validate accelerated test methods used to evaluate the sulfate resistance of cements. Highly penetrating, high-energy X-rays from synchrotron sources allow the use of EDXRD to nondestructively determine depth profiles for the crystalline phases in the cement paste specimens several millimeters below the sample surface. These depth profiles, and how they vary with sulfate exposure conditions and duration, can be correlated with mechanical changes and the crack patterns seen in the microtomographs. Spatially resolved EDXRD is in principle useful for phase composition mapping and depth profiling in a wide range of materials where the attenuation of high energy x-rays is not extreme. Suitable materials include many ceramic compositions.

Depth Profiling by Means of X-Ray Fluorescence Analysis

1991 ◽  
Vol 35 (B) ◽  
pp. 783-794
Author(s):  
H. Ebel ◽  
R. Svagera ◽  
S. Rezai Afshar
Keyword(s):  
Incidence Angle ◽  
Depth Profiling ◽  
Fluorescence Analysis ◽  
X Rays ◽  
Homogeneous Sample ◽  
Fundamental Parameters ◽  
Further Development ◽  
Reference Samples ◽  
Original Concept

Sherman described the excitation of characteristic radiations by primary x-rays and by secondary excitation. The derivation has been made assuming a homogeneous sample. Criss and Birks inverted the problem from the calculation of fluorescent countrates to the quantitative XFA by means of fundamental parameters. Theoretical and instrumental developments enabled a reduction of the sample area and led to small area XFA and imaging XFA sytems. Depth profiling by means of XFA is a further development. We continue the original concept of variable take-off angle technique for the determination of film thicknesses without reference samples and apply the variation of the incidence angle to depth profiling.

Surface Analysis of UO2 Leached in Mineral Water Studied by X-Ray Photoelectron Spectroscopy

1988 ◽  
Vol 127 ◽  
Author(s):  
M. P. Lahalle ◽  
J. C. Krupa ◽  
R. Guillaumont ◽  
M. Genet ◽  
G. C. Allen ◽  
...  
Keyword(s):  
Surface Layer ◽  
Uranium Dioxide ◽  
Photoelectron Spectroscopy ◽  
Uranium Oxide ◽  
Mineral Water ◽  
Depth Profiling ◽  
X Rays ◽  
Xps Analysis ◽  
X Ray ◽  
Layer Analysis

ABSTRACTX-rays photoelectron spectroscopy (XPS) analysis has been carried out on uranium dioxide single crystals placed in both deionised or mineral water at 60 °C and 90 °C for a few months. The surface layer on the sample immersed in mineral water at 90 °C was sufficiently thick to mask the presence of uranium in the recorded XPS spectrum. Depth profiling experiments showed that the deposit was ∼ 100 nm in thickness and revealed the formation of a mixed magnesium-uranium oxide region between the bulk UO2 and the outer magnesium- rich layer. Analysis of the aqueous medium following immersion of the UO2 samples showed that the concentration of uranium released to the mineral water was 10 to 100 times lower than that in deionised water.

Non-destructive elemental depth-profiling with muonic X-rays

2008 ◽  
Vol 278 (3) ◽  
pp. 777-781 ◽  
Author(s):  
M. K. Kubo ◽  
H. Moriyama ◽  
Y. Tsuruoka ◽  
S. Sakamoto ◽  
E. Koseto ◽  
...  
Keyword(s):  
Depth Profiling ◽  
X Rays ◽  
Non Destructive ◽  
Elemental Depth

White-Light Coronal Structures: Streamers and CMEs

1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner
Keyword(s):  
Emission Line ◽  
Electron Density ◽  
White Light ◽  
Coronal Mass Ejections ◽  
X Rays ◽  
Solar Cycles ◽  
Temperature Function ◽  
X Ray ◽  
Eclipse Observations ◽  
Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

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