Diffusion Parameters Determination by a Non-Destructive Technique with an Assumption of Mass Exchange on the Surface

Diffusion of nitrogen implanted in tungsten and molybdenum single crystals has been investigated at temperature about 0.3 Tm (Tm is the melting point). Existence of several dopant atom fluxes is found in subsurface region of the ion implanted material. The diffusion coefficients of the nitrogen connected with the radiation damages and that with the bulk diffusion mechanism are determined. Change of the nitrogen surface concentration has been measured by Auger electron spectroscopy. Initial distribution of the nitrogen and diffusion profiles for various annealing time have been determined by secondary-ion mass-spectroscopy technique. Transmission electron microscopy and X-ray diffraction investigations were used to study the microstructure and phase state of the implanted samples.

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Diffusion Parameters Determination by a Non-Destructive Technique with an Assumption of Mass Exchange on the Surface

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.249.189 ◽

2006 ◽

Vol 249 ◽

pp. 189-192

Author(s):

O.B. Bodnar ◽

I.M. Aristova ◽

A.A. Mazilkin ◽

A.N. Chaika ◽

P.Yu Popov

Keyword(s):

Diffusion Mechanism ◽

Bulk Diffusion ◽

Surface Concentration ◽

Sample Surface ◽

Initial Distribution ◽

Dopant Atom ◽

Subsurface Region ◽

Diffusion Parameters ◽

Radiation Damages ◽

Non Destructive

Theoretical base for non-destructive diffusion parameters determination technique in solids taking into account the dopant flux from the sample surface is presented. Diffusion of the nitrogen implanted in the tungsten single crystals was determined in temperature range 700–820°C. Surface concentration of nitrogen was obtained by Auger electron spectroscopy. Initial distribution of the nitrogen in subsurface region was measured by secondary-ion mass-spectroscopy. Two dopant atom fluxes found in subsurface region of the ion-implanted material are supposed to connect with the radiation damages and with the bulk diffusion mechanism.

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Luminescence from individual dislocations in II-VI and III-V semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088488 ◽

1991 ◽

Vol 49 ◽

pp. 834-835

Author(s):

J W Steeds

Keyword(s):

Group Iv ◽

Luminescence Properties ◽

Carrier Recombination ◽

Transmission Electron ◽

Wide Range ◽

Basic Physics ◽

Semiconducting Compounds ◽

Diamond Group ◽

Non Destructive ◽

Technological Significance

There is a wide range of experimental results related to dislocations in diamond, group IV, II-VI, III-V semiconducting compounds, but few of these come from isolated, well-characterized individual dislocations. We are here concerned with only those results obtained in a transmission electron microscope so that the dislocations responsible were individually imaged. The luminescence properties of the dislocations were studied by cathodoluminescence performed at low temperatures (~30K) achieved by liquid helium cooling. Both spectra and monochromatic cathodoluminescence images have been obtained, in some cases as a function of temperature.There are two aspects of this work. One is mainly of technological significance. By understanding the luminescence properties of dislocations in epitaxial structures, future non-destructive evaluation will be enhanced. The second aim is to arrive at a good detailed understanding of the basic physics associated with carrier recombination near dislocations as revealed by local luminescence properties.

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Forensic Identifications Aided by Scanning Electron Microscopy of Silicone-Epoxy Microreplicas of Calcified and Cornified Structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117017 ◽

1975 ◽

Vol 33 ◽

pp. 678-679 ◽

Cited By ~ 3

Author(s):

R.F. Sognnaes

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Forensic Science ◽

George Washington ◽

Epithelial Surface ◽

Extended Application ◽

Tissue Surfaces ◽

Non Destructive ◽

Scanning Electron ◽

Surface Changes

Sufficient experience has been gained during the past five years to suggest an extended application of microreplication and scanning electron microscopy to problems of forensic science. The author's research was originally initiated with a view to develop a non-destructive method for identification of materials that went into objects of art, notably ivory and ivories. This was followed by a very specific application to the identification and duplication of the kinds of materials from animal teeth and tusks which two centuries ago went into the fabrication of the ivory dentures of George Washington. Subsequently it became apparent that a similar method of microreplication and SEM examination offered promise for a whole series of problems pertinent to art, technology and science. Furthermore, what began primarily as an application to solid substances has turned out to be similarly applicable to soft tissue surfaces such as mucous membranes and skin, even in cases of acute, chronic and precancerous epithelial surface changes, and to post-mortem identification of specific structures pertinent to forensic science.

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