ChemInform Abstract: REDUCTION OF THE DISLOCATION DENSITY IN GALLIUM ARSENIDE ANTIMONIDE (GAAS1-XSBX) LAYER ON GALLIUM ARSENIDE GROWN BY AN IMPROVED LPE METHOD

1980 ◽  
Vol 11 (32) ◽  
Author(s):  
Y. NISHITANI ◽  
K. AKITA ◽  
A. YAMAGUCHI ◽  
T. KOTANI
Keyword(s):  
Gallium Arsenide ◽  
Dislocation Density ◽  
Gallium Arsenide Antimonide

Gallium arsenide antimonide: The possibility of lattice‐matched LPE growth on InP substrates

1978 ◽  
Vol 49 (12) ◽  
pp. 5920-5923 ◽  
Author(s):  
Clifton G. Fonstad ◽  
Maurice Quillec ◽  
Stephen Garone
Keyword(s):  
Gallium Arsenide ◽  
Gallium Arsenide Antimonide ◽  
Inp Substrates ◽  
Lattice Matched

Distribution of Carbon in Large Diameter Semi-Insulating Gallium Arsenide Grown by Liquid Encapsulated Czochralski Technique

2012 ◽  
Vol 472-475 ◽  
pp. 587-590
Author(s):  
Li Hua Wang ◽  
Qiu Yan Hao ◽  
Bing Zhang Wang ◽  
Wei Zhong Sun ◽  
Cai Chi Liu
Keyword(s):  
Gallium Arsenide ◽  
Dislocation Density ◽  
Strain Field ◽  
Elastic Strain ◽  
Radial Direction ◽  
Large Diameter ◽  
Czochralski Technique ◽  
Carbon Impurity ◽  
Distribution Of Dislocations ◽  
Elastic Strain Field

Carbon impurity concentration and dislocation density were investigated with optical microscopy and Fourier transform infrared absorption spectrometer in radial direction of large diameter (6-inch) undoped semi-insulating Gallium Arsenide (SI-GaAs) grown by liquid encapsulated Czochralski (LEC). The experimental results showed that their distributions are both “W”-shaped along wafer diameter, which is relatively higher on the center and lower near the center, but highest on the edge of the wafer. The nonuniformity distribution of thermal stress from growth process leads to the “W”-shaped distribution of dislocations in radial direction. The adsorption of matrix elastic strain field around dislocations induces the “W”-shaped distribution of carbon impurity. Dislocations adsorb carbon impurity and carbon impurity decorates dislocations. Dislocation density distribution affects carbon behavior.

Observations of dislocation interactions with recrystallized grain boundaries

1988 ◽  
Vol 46 ◽  
pp. 628-629
Author(s):  
C. W. Price
Keyword(s):  
Dislocation Density ◽  
Grain Boundary ◽  
Strain Rate ◽  
Grain Boundaries ◽  
Dislocation Structure ◽  
Hot Deformation ◽  
Static Recrystallization ◽  
High Dislocation Density ◽  
High Angle ◽  
Dislocation Interactions

Little evidence exists on the interaction of individual dislocations with recrystallized grain boundaries, primarily because of the severely overlapping contrast of the high dislocation density usually present during recrystallization. Interesting evidence of such interaction, Fig. 1, was discovered during examination of some old work on the hot deformation of Al-4.64 Cu. The specimen was deformed in a programmable thermomechanical instrument at 527 C and a strain rate of 25 cm/cm/s to a strain of 0.7. Static recrystallization occurred during a post anneal of 23 s also at 527 C. The figure shows evidence of dissociation of a subboundary at an intersection with a recrystallized high-angle grain boundary. At least one set of dislocations appears to be out of contrast in Fig. 1, and a grainboundary precipitate also is visible. Unfortunately, only subgrain sizes were of interest at the time the micrograph was recorded, and no attempt was made to analyze the dislocation structure.

Investigation of shock-wave deformation history from recovered structure

1986 ◽  
Vol 44 ◽  
pp. 434-435
Author(s):  
M.A. Mogilevsky ◽  
L.S. Bushnev
Keyword(s):  
Shock Wave ◽  
Plastic Deformation ◽  
Dislocation Density ◽  
Shock Waves ◽  
Shock Front ◽  
Single Crystals ◽  
Residual Deformation ◽  
Deformation Structure ◽  
Deformation History ◽  
Deformation Velocity

Single crystals of Al were loaded by 15 to 40 GPa shock waves at 77 K with a pulse duration of 1.0 to 0.5 μs and a residual deformation of ∼1%. The analysis of deformation structure peculiarities allows the deformation history to be re-established.After a 20 to 40 GPa loading the dislocation density in the recovered samples was about 1010 cm-2. By measuring the thickness of the 40 GPa shock front in Al, a plastic deformation velocity of 1.07 x 108 s-1 is obtained, from where the moving dislocation density at the front is 7 x 1010 cm-2. A very small part of dislocations moves during the whole time of compression, i.e. a total dislocation density at the front must be in excess of this value by one or two orders. Consequently, due to extremely high stresses, at the front there exists a very unstable structure which is rearranged later with a noticeable decrease in dislocation density.

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