Influence of crystallization temperature on growth rate of epitaxial gallium arsenide layers in the system GaAs-AsCl3-H2

1982 ◽  
Vol 25 (9) ◽  
pp. 859-862 ◽  
Author(s):  
L. G. Lavrent'eva ◽  
V. G. Ivanov ◽  
I. V. Ivonin ◽  
V. A. Moskovkin ◽  
S. E. Toropov
Keyword(s):  
Growth Rate ◽  
Gallium Arsenide ◽  
Crystallization Temperature ◽  
Influence Of Crystallization

A polycentric growth model of gallium arsenide epitaxial layers from the gas phase with simultaneous diffusion, adsorption and chemical reaction

1988 ◽  
Vol 53 (12) ◽  
pp. 2995-3013
Author(s):  
Emerich Erdös ◽  
Jindřich Leitner ◽  
Petr Voňka ◽  
Josef Stejskal ◽  
Přemysl Klíma
Keyword(s):  
Growth Rate ◽  
Gallium Arsenide ◽  
Epitaxial Growth ◽  
Gas Phase ◽  
Surface Reaction ◽  
Quantitative Description ◽  
The Other ◽  
Rate Equations ◽  
Impact Interaction ◽  
Partial Pressures

For a quantitative description of the epitaxial growth rate of gallium arsenide, two models are proposed including two rate controlling steps, namely the diffusion of components in the gas phase and the surface reaction. In the models considered, the surface reaction involves a reaction triple - or quadruple centre. In both models three mechanisms are considered which differ one from the other by different adsorption - and impact interaction of reacting particles. In every of the six cases, the pertinent rate equations were derived, and the models have been confronted with the experimentally found dependences of the growth rate on partial pressures of components in the feed. The results are discussed with regard to the plausibility of individual mechanisms and of both models, and also with respect to their applicability and the direction of further investigations.

Phase separation in undercooled molten Pd80Si20: Part I

1999 ◽  
Vol 14 (9) ◽  
pp. 3653-3662 ◽  
Author(s):  
K. L. Lee ◽  
H. W. Kui
Keyword(s):  
Growth Rate ◽  
Phase Separation ◽  
Crystal Growth ◽  
Grain Refinement ◽  
Crystallization Temperature ◽  
Sharp Decrease ◽  
Nucleation And Growth ◽  
Crystal Growth Rate ◽  
Large Undercooling ◽  
Kinetic Crystallization

Three different kinds of morphology are found in undercooled Pd80Si20, and they dominate at different undercooling regimens ΔT, defined as ΔT = T1 – Tk, where T1 is the liquidus of Pd80Si20 and Tk is the kinetic crystallization temperature. In the small undercooling regimen, i.e., for ΔT ≤ 190 K, the microstructures are typically dendritic precipitation with a eutecticlike background. In the intermediate undercooling regimen, i.e., for 190 ≤ ΔT ≤ 220 K, spherical morphologies, which arise from nucleation and growth, are identified. In addition, Pd particles are found throughout an entire undercooled specimen. In the large undercooling regimen, i.e., for ΔT ≥ 220 K, a connected structure composed of two subnetworks is found. A sharp decrease in the dimension of the microstructures occurs from the intermediate to the large undercooling regimen. Although the crystalline phases in the intermediate and the large undercooling regimens are the same, the crystal growth rate is too slow to bring about the occurrence of grain refinement. Combining the morphologies observed in the three undercooling regimens and their crystallization behaviors, we conclude that phase separation takes place in undercooled molten Pd80Si20.

Effects of crystallization temperature on the growth and doping of autoepitaxial gallium arsenide films

1973 ◽  
Vol 16 (6) ◽  
pp. 794-797
Author(s):  
L. G. Lavrent'eva ◽  
I. V. Ivonin ◽  
L. M. Krasil'nikova ◽  
Yu. M. Rumyantsev ◽  
M. P. Yakubenya
Keyword(s):  
Gallium Arsenide ◽  
Crystallization Temperature

Research on Preparation Technology for Machinable Ceramics

2014 ◽  
Vol 804 ◽  
pp. 203-206
Author(s):  
Hao Zhang ◽  
Yan Xu ◽  
Hai Yun Jin ◽  
Guan Jun Qiao
Keyword(s):  
Heat Treatment ◽  
Growth Rate ◽  
Phase Composition ◽  
Crystallization Temperature ◽  
Treatment Process ◽  
Glass Ceramics ◽  
Heat Treatment Process ◽  
Preparation Technology ◽  
The Relationship ◽  
Sintering Method

In this paper, the compact SiO2-B2O3-Al2O3-MgO-F machinable ceramics were prepared through melt-cast and sintering method. The phase composition and microstructure of the ceramics were analyzed and observed using XRD and SEM, and the relationship between processing and microstructure were discussed. The results showed that, after the heat treatment, the main phase of the ceramics changed from fluorophlogopite (mica like) to fluoramphibole (rod like). When the crystallization temperature at 950°C, the nuclei growth rate of the mica glass-ceramics was higher. Meanwhile, a small quantity of forsterite (Mg2SiO4) was also crystallized out in the process. The best heat treatment process was nucleated at 630°C for 2h and crystallized at 950°C for 2h.

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