The rheology of olivine and spinel magnesium germanate (Mg 2 GeO 4 ): TEM study of the defect microstructures

The defect microstructures of Si arising from ion implantation and subsequent regrowth for a (111) substrate have been found to be dominated by microtwins. Figure 1(a) is a typical diffraction pattern of annealed ion-implanted (111) Si showing two groups of extra diffraction spots; one at positions (m, n integers), the other at adjacent positions between <000> and <220>. The object of the present paper is to show that these extra reflections are a direct consequence of the microtwins in the material.

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Radiation-Induced Precipitation in Ti-6A1-4V

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600000659 ◽

1980 ◽

Vol 38 ◽

pp. 154-155

Author(s):

J. E. O'Neal ◽

S. M. L. Sastry ◽

J. W. Davis

Keyword(s):

Dark Field ◽

Dislocation Loops ◽

Beta Titanium Alloy ◽

Defect Clusters ◽

Weak Beam ◽

Beta Titanium ◽

Small Defect ◽

Radiation Induced ◽

Vector Orientation ◽

Defect Microstructures

The radiation-induced defect structure and nonequilibrium phase precipitation were studied in T1-6A1-4V (an alpha-beta titanium alloy), irradiated at 450 ± 30°C in row VII of the EBR-II to a fluence of 3.0 × 1021 neutrons/cm2 (En > 0.1 MeV). The Irradiation-induced defect microstructures were examined using bright-field, conventional dark-field, and weak-beam dark-field techniques. The nature of dislocations and dislocation loops was determined by standard-contrast experiments under two-beam conditions, and the small defect clusters were identified using the line-of-contrast criterion and black-white vector orientation criterion.

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Determination of the olivine-spinel transition in magnesium germanate (Mg2GeO4) up to 20 kilobars and 1300°C

Physics of The Earth and Planetary Interiors ◽

10.1016/0031-9201(77)90145-5 ◽

1977 ◽

Vol 14 (2) ◽

pp. P3-P5 ◽

Cited By ~ 2

Author(s):

B.J Hensen

Keyword(s):

Magnesium Germanate

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Crystal structures of quartz and magnesium germanate by profile analysis of synchrotron-radiation high-resolution powder data

Journal of Applied Crystallography ◽

10.1107/s0021889887011567 ◽

1988 ◽

Vol 21 (2) ◽

pp. 182-191 ◽

Cited By ~ 99

Author(s):

G. Will ◽

M. Bellotto ◽

W. Parrish ◽

M. Hart

Keyword(s):

High Resolution ◽

Synchrotron Radiation ◽

Crystal Structures ◽

Profile Analysis ◽

Magnesium Germanate

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Effect of Energy and Dose on Transient-Enhanced Diffusion and Defect Microstructure in Low Energy High Dose As+ Implanted Si

MRS Proceedings ◽

10.1557/proc-438-21 ◽

1996 ◽

Vol 438 ◽

Author(s):

V. Krishnamoorthy ◽

D. Venables ◽

K. Moeller ◽

K. S. Jones ◽

B. Freer

Keyword(s):

Point Defects ◽

Surface Recombination ◽

High Dose ◽

Enhanced Diffusion ◽

Projected Range ◽

Diffusion Enhancement ◽

Defect Microstructures ◽

Dose Dependent ◽

Higher Doses ◽

Defect Microstructure

Abstract(001) CZ silicon wafers were implanted with arsenic (As+) at energies of 10–50keV to doses of 2×1014 to 5×1015/cm2. All implants were amorphizing in nature. The samples were annealed at 700°C for 16hrs. The resultant defect microstructures were analyzed by XTEM and PTEM and the As profiles were analyzed by SIMS. The As profiles showed significantly enhanced diffusion in all of the annealed specimens. The diffusion enhancement was both energy and dose dependent. The lowest dose implant/annealed samples did not show As clustering which translated to a lack of defects at the projected range. At higher doses, however, projected range defects were clearly observed, presumably due to interstitials generated during As clustering. The extent of enhancement in diffusion and its relation to the defect microstructure is explained by a combination of factors including surface recombination of point defects, As precipitation, As clustering and end of range damage.

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