Naica’s Giant Crystals: Characterization and Evolution of the Wall–Crystal Interface

The continuous-feeding Czochralski method is a cost-effective method to grow single silicon crystals. An inner crucible is used to prevent the un-melted silicon feedstock from transferring to the melt-crystal interface in this method. A series of global simulations were carried out to investigate the impact of the inner crucible on the oxygen impurity distributions at the melt-crystal interface. The results indicate that, the inner crucible plays a more important role in affecting the O concentration at the melt-crystal interface than the outer crucible. It can prevent the oxygen impurities from being transported from the outer crucible wall effectively. Meanwhile, it also introduces as a new source of oxygen impurity in the melt, likely resulting in a high oxygen concentration zone under the melt-crystal interface. We proposed to enlarge the inner crucible diameter so that the oxygen concentration at the melt-crystal interface can be controlled at low levels.

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Diffusion Enhancement in Glassy Metals Under Non-Equilibrium Conditions

MRS Proceedings ◽

10.1557/proc-400-149 ◽

1995 ◽

Vol 400 ◽

Author(s):

S. Bellini ◽

G. Mazzone ◽

A. Montone ◽

M. Vittori-antisari Enea ◽

C.R. Casaccia

Keyword(s):

Free Volume ◽

Growth Kinetics ◽

Bulk Diffusion ◽

High Energy ◽

First Case ◽

Diffusion Enhancement ◽

Glass Crystal ◽

Kinetics Of ◽

Crystal Interface ◽

Diffusion Properties

AbstractThe diffusion properties of a Ni-Zr metallic glass formed at the interface of a bulk diffusion couple have been studied in conditions far from a fully relaxed state. The growth kinetics of the interface film have been enhanced by both plastic deformation and high energy electron irradiation. Different results have been obtained in the two cases, since in the first case the film grows exponentially with time, while in the second case the usual square root dependence on time is observed. This behaviour has been interpreted as a consequence of the annihilation kinetics of the excess free volume introduced in the glass by the above methods. Two different mechanisms of free volume annihilation , namely exchange with a crystal vacancy at the glass-crystal interface and structural relaxation in the bulk glassy phase have been considered to be operative so that the nature of the growth kinetics has been found to depend on the mechanism predominant in each experimental condition.

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A new pathway for the formation of radial nematic droplets within a lipid-laden aqueous-liquid crystal interface

RSC Advances ◽

10.1039/c3ra48044e ◽

2014 ◽

Vol 4 (36) ◽

pp. 18889-18893 ◽

Cited By ~ 17

Author(s):

Sumyra Sidiq ◽

Dibyendu Das ◽

Santanu Kumar Pal

Keyword(s):

Liquid Crystal ◽

Topological Defects ◽

Soft Materials ◽

Stimuli Responsive ◽

First Time ◽

Crystal Interface

A new pathway for the formation of liquid crystal (LC) droplets with radial LC ordering is reported for the first time in the presence of surfactants and lipids. Interactions of an enzyme with the topological defects in the LC mediate the response of these droplets and thus provide new designs for stimuli-responsive soft materials.

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Numerical Study of the Effect of Magnetic Fields on Melt-Crystal Interface-Deflection in Czochralski Crystal Growth

Heat Transfer: Volume 3 ◽

10.1115/ht2003-47534 ◽

2003 ◽

Cited By ~ 2

Author(s):

Lijun Liu ◽

Koichi Kakimoto

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Numerical Study ◽

Silicon Crystal ◽

Czochralski Growth ◽

Thermal Flow ◽

Interface Shape ◽

Convective Thermal ◽

And Control ◽

Crystal Interface

In order to control the impurity distribution and remove defects in a crystal grown in Czochralski growth for high quality crystals of silicon, it is necessary to study and control the melt-crystal interface shape, which plays an important role in control of the crystal quality. The melt-crystal interface interacts with and is determined by the convective thermal flow of the melt in the crucible. Application of magnetic field in the Czochralski system is an effective tool to control the convective thermal flow in the crucible. Therefore, the shape of the melt-crystal interface can be modified accordingly. Numerical study is performed in this paper to understand the effect of magnetic field on the interface deflection in Czochralski system. Comparisons have been carried out by computations for four arrangements of the magnetic field: without magnetic field, a vertical magnetic field and two types of cusp-shaped magnetic field. The velocity, pressure, thermal and electromagnetic fields are solved with adaptation of the mesh to the iteratively modified interface shape. The multi-block technique is applied to discretize the melt field in the crucible and the solid field of silicon crystal. The unknown shape of the melt-crystal interface is achieved by an iterative procedure. The computation results show that the magnetic fields have obvious effects on both the pattern and strength of the convective flow and the interface shape. Applying magnetic field in the Czochralski system, therefore, is an effective tool to control the quality of bulk crystal in Czochralski growth process.

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