Migrations of Interstitial Atoms in Semiconductors (Surface Diffusion and Kick-Out Mechanism)

1989 ◽  
Vol 163 ◽  
Author(s):  
Takao Wada ◽  
Akihiro Takeda ◽  
Masaya Ichimura ◽  
Michihiko Takeda
Keyword(s):  
Electron Beam ◽  
Surface Diffusion ◽  
High Energy ◽  
Gaas Substrates ◽  
High Energy Electrons ◽  
Interstitial Atoms

AbstractGe and Zn atoms were introduced into the unirradiated regions of Si at 150°C and GaAs wafers at 50°C, respectively by using the electron-beam doping method. The surfaces of Si and GaAs substrates were covered partially by the overlayers of Ge and Zn sheets, respectively. The only surfaces of the Ge and Zn sheets were irradiated locally. with high energy electrons at 7MeV with the fluences of 5×1017 – 1×1018 electrons cm-2 . Even at a distance of ~10mm from the irradiated overlayers in the Si and GaAs substrates, Ge and Zn atoms respectively, whose interstitials may migrate the unirradiated regions, were detected by SIMS measurements. PL signal due to band-to-acceptor (ZnGa ) transition at 1.48eV becomes observable after annealing at 800°C for 20mm in the unirradiated GaAs region, which is separated from Zn sheet by nearly 10mm.

scholarly journals Особенности применения электронов в исследовании пленок гексаферрита бария на c-сапфире

2021 ◽  
Vol 47 (1) ◽  
pp. 31
Author(s):  
А.Э. Муслимов ◽  
М.Г. Исмаилов ◽  
В.М. Каневский
Keyword(s):  
Magnetic Field ◽  
Electron Beam ◽  
Easy Axis ◽  
Film Formation ◽  
High Energy ◽  
Beam Deflection ◽  
Angle Of Incidence ◽  
High Energy Electrons

Processes of film formation (0001) BaFe12O19 on sapphire with ferromagnetic "easy axis" directed along normal to substrate are investigated. Propagation of the beam of high-energy electrons during interaction with the (0001) BaFe12O19 film was studied depending on the angle of incidence of the beam. Deflection of sliding electron beam by magnetic field of (0001) BaFe12O19 film is demonstrated. It is shown that the presence of (0001) BaFe12O19 film on sapphire leads to the redistribution of cathodoluminescence in it mainly to the "red" region. The radiation associated with the film itself was not detected in the experiment.

The application of scanning electron beam anomalous transmission patterns in mineralogy

1969 ◽  
Vol 37 (286) ◽  
pp. 270-274 ◽  
Author(s):  
M. P. Jones ◽  
J. Gavrilovic
Keyword(s):  
Electron Beam ◽  
High Energy ◽  
Crystallographic Structure ◽  
Scattered Electron ◽  
Scanning Electron Beam ◽  
Large Bulk ◽  
High Energy Electrons ◽  
Anomalous Transmission ◽  
Solid Bulk ◽  
Scanning Electron

SummaryIt is possible with a standard Geoscan microanalyser to produce back-scattered electron pictures that resemble Kikuchi patterns but which are produced by a different mechanism. These effects have been called scanning electron beam anomalous transmission (SEBAT) patterns and they are produced by the interaction of a parallel scanning beam of high-energy electrons with a crystalline sample. The patterns are excellent indicators of the crystallographic perfection and orientation of samples and can provide information about the lattice dimensions of solid, bulk specimens. The same specimens can, if necessary, be chemically analysed in the same instrument.In order to produce the patterns the electron beam must be deflected through a minimum angle of approximately 20° and, on existing instruments, the beam covers an area of about 2 × 2 mm during such a deflection. Minor modification of the authors' microanalyser has reduced the scanned area to 0·5 × 0·5 mm and attempts are being made to reduce this even further.In favourable circumstances the technique enables the mineralogist to determine, rapidly and easily, the crystallographic structure and orientation of large, bulk specimens. Examples are given of patterns that have been produced from cleaved, as grown, and polished mineral faces. The degree and nature of the crystallographic damage produced during mechanical polishing of a galena crystal are illustrated.

Studies of Oxide Desorption From GaAs by Diffuse Electron Scatfering and Optical Reflectivity

1991 ◽  
Vol 222 ◽  
Author(s):  
T. Van Buuren ◽  
T. Tiedje ◽  
M. K. Weilmeier ◽  
K. M. Colbow ◽  
J. A. Mackenzie
Keyword(s):  
Oxygen Plasma ◽  
Oxide Thickness ◽  
High Energy ◽  
Secondary Electrons ◽  
Oxide Layers ◽  
Gaas Substrates ◽  
Pressure Oxygen ◽  
High Energy Electrons ◽  
Order Of Magnitude ◽  
Magnitude Increase

ABSTRACTWe have determined that the temperature for desorption of gallium oude from GaAs increases linearly with oxide thickness, for oxide layers between about 6Å and 26Å thick. Different thicknesses of oxide layers were created by varying the exposure time of the GaAs wafers to a low pressure oxygen plasma. In addition, we show by diffuse light scattering that highly polished GaAs substrates roughen during the oxide desorption. These results are interpreted in terms of a model in which the oxide evaporates inhomogeneously. The oxide desorption was also studied by monitoring the secondary electrons produced by the high energy electrons from the RHEED gun. After the gallium oxide desorption there is a reversible, order of magnitude, increase in the number of secondary electrons produced. We interpret this result as evidence for the formation of microscopic gallium droplets on the GaAs surface.

High-resolution planar electron beam induced current in bulk diodes using high-energy electrons

2021 ◽  
Vol 119 (1) ◽  
pp. 014103
Author(s):  
Zoey Warecki ◽  
Andrew A. Allerman ◽  
Andrew M. Armstrong ◽  
A. Alec Talin ◽  
John Cumings
Keyword(s):  
Electron Beam ◽  
High Resolution ◽  
High Energy ◽  
Induced Current ◽  
High Energy Electrons ◽  
Electron Beam Induced Current ◽  
Planar Electron

Electron-beam-induced deposition using a subnanometer-sized probe of high-energy electrons

2003 ◽  
Vol 83 (10) ◽  
pp. 2064-2066 ◽  
Author(s):  
K. Mitsuishi ◽  
M. Shimojo ◽  
M. Han ◽  
K. Furuya
Keyword(s):  
Electron Beam ◽  
High Energy ◽  
High Energy Electrons ◽  
Electron Beam Induced Deposition

Electron microprobe analysis: The upper limit of submicron spectroscopy

1986 ◽  
Vol 44 ◽  
pp. 744-747
Author(s):  
Paul F. Hlava ◽  
William F. Chambers
Keyword(s):  
Electron Beam ◽  
Electron Microprobe ◽  
Region Of Interest ◽  
High Energy ◽  
Atomic Weight ◽  
X Rays ◽  
Beam Voltage ◽  
Large Numbers ◽  
High Energy Electrons ◽  
Beam Interaction

In the electron microprobe, a beam of high energy electrons is focussed to a fine point on the surface of a fairly thick specimen and the x rays produced are analyzed to determine the chemistry of the "point". The spa- cial resolution of this instrument for chemical analysis, then, is defined by the volume of material from which the x ray signal originates. This, in turn, is related to factors such as the diameter of the electron beam, the spreading of the electron beam as it penetrates into the sample and interacts with the atoms of the sample to generate x rays, and the extent to which these primary x rays penetrate beyond the region of electron beam interaction and generate secondary x rays by the process of fluorescence. Beam voltage, current, and diameter can all be easily controlled by the analyst. Once the electrons enter the specimen, however, the analyst loses control of their density. Each individual electron follows a unique, erratic path as it passes near, passes through, or collides with parts of the atoms in the specimen. Monte Carlo calculations are a means by which many investigators have tried to model the paths of individual electrons and the interation volume that large numbers of such electrons define.3 “* It is well known that the size and shape of the region into which the electron beam penetrates and expends its energy is controlled primarily by the average atomic number, atomic weight, and density of the specimen in the region of interest and the beam voltage.

Physical and Technological Features of Formation of Large Thickness Welded Joints in Electron-Beam Welding

2017 ◽  
Vol 265 ◽  
pp. 237-244 ◽  
Author(s):  
V.V. Novokreschenov ◽  
R.V. Rodyakina ◽  
M.A. Karimbekov
Keyword(s):  
Electron Beam ◽  
Electron Beam Welding ◽  
Melting Zone ◽  
High Energy ◽  
After Effects ◽  
Large Thickness ◽  
High Energy Electrons ◽  
Plasma State ◽  
Gas Kinetic Theory ◽  
Depth Increase

In this paper, based on the gas-kinetic theory of plasma, a theoretical analysis of the possibility of forming a plasma state in melting channel as a result of the interaction of high-energy electrons of the electron beam with the atoms of the material, being processed in melting channel (in free state) is proposed. Also the assessment of a possible impact of this process on the quality of weld metal is given. It is shown that if we take the electron-beam welding of large thickness with formation of a knife-form melting zone, the occurring processes can develop both in the direction of self-organization (synergetic, evolution) and chaotically (it all depends on the set of after-effects, caused by them, and their duration), which is manifested either as autofocusing and melted depth increase (synergy, evolution) or as formation of defects in the center of the channel (in the central part of the weld) in the form of steam and gas cavities of quite considerable size.

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