Transport phenomena in the UCC process are important in that they effect the quality of the crystal. Hence the heat, fluid flow and mass transfer must be considered in order to understand crystal growth. A numerical model has been developed for the prediction of temperature, velocity, and concentration fields. The governing equations have been discretized using the control-volume based on the finite difference method. The effects of convection on the solute profiles both in the melt and in the crystal have been studied. Attention is also focused both on the initial transient stage of solte redistribtuion and on the radial inhomogeneity of the solute concentration in the grown crystal. The effects of process variables, such as mold length, crucible wall temperature, and crystal pulling speed upon transport phenomena have been investigated. |
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