The use and characterization of a backilluminated charge-coupled device in investigations of pulsed x-ray and radiation sources

ABSTRACTTungsten silicide samples were formed by sputter depositing 80 nm W metal onto (100) oriented, 5 ohm-cm Si wafers. After deposition, the samples were fast radiatively processed in an RTA system using quartz-halogen tungsten lamps as radiation sources for time intervals ranging from 20 to 60s under high vacuum. Films processed at 22–25 W/cm2 radiation with the film side of the samples oriented away from the lamps result in films which are metallic or cloudy in color, and have mixed composition as evidenced by x-ray diffraction (W, W5 Si3 and WSi2). Films processed with the film side oriented toward the lamps show the occurrence of a phase transforF.ation clearly nucleated at the film edge. The new phase is grey and mostly composed of WSi2, with film resistivities 55–60 μΩ-cm. AES measurements show a uniformly distributed Si diffusion profile into the metal film, while SEM indicates a nucleation and growth of the phase once diffusion occurs.

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Fluorescence Yield Xanes and Exafs Experiments: Application to Highly Dilute and Surface Samples

Advances in X-ray Analysis ◽

10.1154/s0376030800016165 ◽

1993 ◽

Vol 37 ◽

pp. 607-617 ◽

Cited By ~ 2

Author(s):

Glenn A. Waychunas ◽

Gordon E. Brown

Keyword(s):

Bound State ◽

Fluorescence Yield ◽

Interatomic Distances ◽

Edge Structure ◽

X Ray ◽

Surface Samples ◽

Radiation Sources ◽

To Come ◽

X Ray Absorption

The development of intense synchrotron radiation sources during the last twenty years has enabled several types of x-ray spectroscopy and scattering techniques to come into practical use. One of the most significant methods for the characterization of extremely dilute samples is high resolution x-ray absorption-edge spectroscopy. The technique is usually divided into two separate methods according to whether the x-ray absorption near edge structure (XANES) or the extended x-ray absorption fine structure (EXAFS) is analyzed. XANES features are due mainly to bound-state electronic transitions just below, and on the low energy side of the edge, and to multiple scattering resonances on the top of the edge and at somewhat higher energies. EXAFS features are oscillations due to ejected photoelectron back scattering interference processes in the close vicinity of the absorber atom. XANES analysis is used to determine atom valence, atom site distortion from regular geometries, and other details of the atom site. EXAFS features can be analyzed to recover interatomic distances between the absorber atom and its first few shells of neighbors, as well as the number and types of these neighbors. Together these techniques can provide an atomspecific probe of die short-range structure within almost any type of condensed matter.

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Characterization of a deep depletion, back-illuminated charge-coupled device in the x-ray range

Review of Scientific Instruments ◽

10.1063/1.2093767 ◽

2005 ◽

Vol 76 (11) ◽

pp. 116101 ◽

Cited By ~ 22

Author(s):

Flavio Zamponi ◽

Tino Kämpfer ◽

Andreas Morak ◽

Ingo Uschmann ◽

Eckhart Förster

Keyword(s):

Charge Coupled Device ◽

X Ray ◽

Back Illuminated

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Diffraction imaging of polycrystalline materials

Journal of Materials Research ◽

10.1557/jmr.1991.1469 ◽

1991 ◽

Vol 6 (7) ◽

pp. 1469-1476 ◽

Cited By ~ 3

Author(s):

David R. Black ◽

Harold E. Burdette ◽

Masao Kuriyama ◽

Richard D. Spal

Keyword(s):

Imaging System ◽

Imaging Technique ◽

Polycrystalline Materials ◽

Charge Coupled Device ◽

X Ray ◽

Diffraction Imaging ◽

Residual Strains ◽

Individual Grains ◽

Ccd Detectors

A new diffraction imaging technique for the characterization of polycrystalline materials is proposed and applied to obtain direct information about individual grains and their size and shape distributions and, in turn, strains in these materials. Unlike traditional powder diffractometry, where divergent and focusing x-ray optics are essential to collect information from an ensemble of grains, the nearly parallel and monochromatic beam available from a synchrotron x-ray source is employed to observe and measure diffraction images from individual grains and component particles in consolidated materials prepared by various processes. Images can be recorded by traditional methods, such as film and pulse counting detectors, but modern image detectors, such as charge coupled device (CCD) detectors and image analyzers, make the proposed imaging technique more practical. Unlike traditional diffractometry, this new technique provides the ability to measure shape, size, and strain without model based analyses. The spatial distribution of strain within individual grains, displayed as a diffraction image (topograph), indicates the presence of defects, such as dislocations, subgrain boundaries, and precipitates, and sheds new light on the origins of residual strains (stresses) in industrial materials. The resolution of the imaging system used is limited to grains ∼10 μm or larger due to diffraction broadening (∼20” from the size effect) and the resolution of the recording medium.

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Experience with Imaging by Using of Microfocus X-Ray Source

Journal of Electrical Engineering ◽

10.2478/v10187-010-0042-3 ◽

2010 ◽

Vol 61 (5) ◽

pp. 287-290 ◽

Cited By ~ 2

Author(s):

Zdenko Zápražný ◽

Dušan Korytár ◽

František Dubecký ◽

Vladimír Áč ◽

Zbigniew Stachura ◽

...

Keyword(s):

Synchrotron Radiation ◽

Phase Contrast ◽

Ccd Camera ◽

X Ray ◽

X Ray Imaging ◽

Radiation Sources ◽

Set Up ◽

High Level ◽

Very High

Experience with Imaging by Using of Microfocus X-Ray SourceIn this paper we present the current work and experience with using microfocus x-ray generator and commercial CCD camera for x-ray imaging purpose. There is a need in laboratories for the development of imaging methods approaching synchrotron radiation sources, where the brilliance of radiation is on very high-level. Generally, there is no continuous access to synchrotron facilities. Several synchrotron radiation laboratories allocate the access via a proposal system. Thus the time for synchrotron radiation experiments seldom exceeds more than 1-2 weeks per year, which restricts its application to a few selected experiments. Even in future, the routine characterization of samples will be performed mainly at the experimenters home laboratories [10]. In this contribution we show that with the present set-up it is possible to achieve the spatial resolution down to μm and with the appropriate geometry a phase contrast images are observable.

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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High Resolution Replication of Organoclay Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055126 ◽

1982 ◽

Vol 40 ◽

pp. 576-577

Author(s):

W. W. Barker ◽

W. E. Rigsby ◽

V. J. Hurst ◽

W. J. Humphreys

Keyword(s):

Clay Mineral ◽

Organic Molecule ◽

Organic Molecules ◽

X Ray Diffraction ◽

Xrd Pattern ◽

X Ray ◽

Naturally Occurring ◽

Silicate Layers ◽

Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

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Digital x-ray mapping of nanometer-size supported bimetallic catalysts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104716 ◽

1988 ◽

Vol 46 ◽

pp. 530-531

Author(s):

L. T. Germinario

Keyword(s):

Background Radiation ◽

Metal Cluster ◽

Single Element ◽

Beam Diameter ◽

X Rays ◽

X Ray ◽

Major Interest ◽

Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

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Plant Pathology Diagnosed by X-Ray Microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100129152 ◽

1987 ◽

Vol 45 ◽

pp. 974-975

Author(s):

J. H. Resau ◽

N. Howell ◽

S. H. Chang

Keyword(s):

Electron Microscopy ◽

Plant Pathology ◽

Biochemical Characterization ◽

Nutrient Deficiency ◽

Green Leaf ◽

Parasitic Infestation ◽

X Ray

Spinach grown in Texas developed “yellow spotting” on the peripheral portions of the leaves. The exact cause of the discoloration could not be determined as there was no evidence of viral or parasitic infestation of the plants and biochemical characterization of the plants did not indicate any significant differences between the yellow and green leaf portions of the spinach. The present study was undertaken using electron microscopy (EM) to determine if a micro-nutrient deficiency was the cause for the discoloration.Green leaf spinach was collected from the field and sent by express mail to the EM laboratory. The yellow and equivalent green portions of the leaves were isolated and dried in a Denton evaporator at 10-5 Torr for 24 hrs. The leaf specimens were then examined using a JEOL 100 CX analytical microscope. TEM specimens were prepared according to the methods of Trump et al.

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