Global analysis of heat transfer in CZ crystal growth of oxide taking into account three-dimensional unsteady melt convection: Effect of meniscus shape

The numerical modeling of melt flow, heat transfer and impurity (phosphorus) diffusion in the double crucible of "Redmet-90M" Cz puller was carried out in an application to a 200 mm diameter Si single crystal growth. The double crucible consists of two coaxial crucibles having different sizes: 490 mm (external) and 300 mm (internal) inner diameters. The bottom of internal crucible has a central hole of Do = 6 and 12 mm diameter for melt inflow from the external crucible. During crystal pulling the granulated Si was added in the external crucible and a melt of the internal crucible was doped by phosphorus. Three-dimensional features of a rotating melt flow affecting on heat transfer and impurity diffusion in the internal crucible were analyzed. In particular, the melt precession and thermal asymmetry near the liquid-solid interface (LSI) in the internal crucible are discussed. It is shown that a significant phosphorus losses caused by its evaporation from a melt surface may be compensated by additional phosphorus doping in the internal crucible.

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Global Analysis of Heat Transfer in CZ Crystal Growth of Oxide.

JOURNAL OF CHEMICAL ENGINEERING OF JAPAN ◽

10.1252/jcej.27.25 ◽

1994 ◽

Vol 27 (1) ◽

pp. 25-31 ◽

Cited By ~ 45

Author(s):

Takao Tsukada ◽

Mitsunori Hozawa ◽

Nobuyuki Imaishi

Keyword(s):

Heat Transfer ◽

Crystal Growth ◽

Global Analysis

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Modeling and Simulation of MHD Melt Convection and Heat Transfer in CZ Crystal Growth

2018 Chinese Automation Congress (CAC) ◽

10.1109/cac.2018.8623579 ◽

2018 ◽

Author(s):

Ni Zhang ◽

Ding Liu ◽

Weichao Huang

Keyword(s):

Heat Transfer ◽

Crystal Growth ◽

Modeling And Simulation ◽

Convection And Heat Transfer ◽

Melt Convection

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Modeling of Fluid Flow and Heat Transfer in a Hydrothermal Crystal Growth System: Use of Fluid-Superposed Porous Layer Theory

Journal of Heat Transfer ◽

10.1115/1.2826055 ◽

1999 ◽

Vol 121 (4) ◽

pp. 1049-1058 ◽

Cited By ~ 24

Author(s):

Q.-S. Chen ◽

V. Prasad ◽

A. Chatterjee

Keyword(s):

Heat Transfer ◽

Crystal Growth ◽

Porous Layer ◽

Hydrothermal System ◽

Growth Process ◽

Three Dimensional ◽

Seed Region ◽

Porous Bed ◽

Flow And Heat Transfer ◽

Growth System

Hydrothermal synthesis, which uses aqueous solvents under high pressure and relatively low temperature, is an important technique for difficult to grow crystalline materials. It is a replica of crystal growth under geological conditions. A hydrothermal growth system usually consists of finely divided particles of the nutrient, predetermined volume of a solvent and a suitably oriented crystal seed (Fig. 1) under very high pressures, generally several thousand bar. The nutrient dissolves at a higher temperature in the lower region, moves to the upper region due to buoyancy-induced convective flows, and deposits on the seed due to lower solubility if the seed region is maintained at a lower temperature. The system can be modeled as a composite fluid and porous layer using the Darcy-Brinkman-Forchheimer flow model in the porous bed. Since the growth process is very slow, the process is considered quasi-steady and the effect of dissolution and growth is neglected. This first study on transport phenomena in a hydrothermal system therefore focuses on the flow and temperature fields without the presence of the seed and mass transfer. A three-dimensional algorithm is used to simulate the flow and heat transfer in a typical autoclave system. An axisymmetric flow pattern at low Grashof numbers becomes three-dimensional at high Grashof numbers. A reduction in the porous bed height for fixed heated and cooled regions can result in oscillatory flows. These results, for the first time, depict the possible flow patterns in a hydrothermal system, that can have far reaching consequences on the growth process and crystal quality.

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