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The traveling solvent method known as TSM is a process used to produce pure and homogeneous crystals structures. TSM has been tested on many alloys producing uniform and uncontaminated single crystals. In the present study the effect of buoyancy convection on the growth of the S[i.sub.0.02]G[e.sub.0.98] crystal grown by the traveling solvent method is investigated under different heating conditions. The full Navier-Stokes equations together with the energy and solutal equations are solved numerically using the finite element technique. The model takes into consideration the losses of heat by radiation and the use of the phase diagram to determine the silicon concentration at the growth interface. Results reveal a strong convection in the solvent, which in turn is detrimental to the growth uniformity in the crystal rod. Additional numerical results show that the convective heat transfer significantly influences the solute distribution in the liquid zone and affects the growth rate substantially. Qualitative comparison of the numerical results with the experiment conducted at Dalhousie University showed a good agreement for the silicon concentration at the growth interface.

Byline: M. Sohail, M.Z. Saghir, T.J. Makriyannis A numerical simulation study is carried out for the crystal growth of Ge1-xSix by the Travelling Heater Method (THM). The effects of a geometrical misalignment and rotation on the crystal growth are investigated. The full Navier-Stokes equations together with the energy, mass transport and continuity equations are solved numerically using the finite element technique. The application of a crucible rotation and misalignment is shown to have a considerable effect on the buoyancy induced flow. An optimal rotational speed was found that lessened the convective flow and provided a uniform concentration along the growth interface.

Byline: T.J. Makriyannis, M.Z. Saghir, D. Labrie The travelling solvent method known as TSM is a process used to produce pure and homogeneous crystals. The TSM process has been tested on many alloys producing uniform and uncontaminated crystal products. A three-dimensional numerical simulation for the fluid flow, heat and mass transfer in the solvent during the growth of Ge1-xSix by the travelling solvent method under axial rotation has been modelled. The full Navier-Stokes equations together with the energy, mass transport and continuity equations were solved numerically using the finite element technique. The application of crucible rotation to the travelling solvent method is an attempt to control the buoyancy induced convection throughout the melt and to suppress the three-dimensional characteristics of unsteady heat flow. The application of rotation was shown to have a considerable effect on the buoyancy-induced flow. An optimal rotational speed was found that lessened the convective flow, provided a uniform concentration along the growth interface, and gave symmetrical characteristics to the three-dimensional buoyancy-induced flow.