Thermocapillary convection

Single crystal silicon is one of the important fundamental materials for the modern photovoltaic industry. The Czochralski method of growing single crystal silicon is affected by the thermocapillary convection. Temperature and concentration gradients at the free surface of the melt give rise to surface tension-driven Marangoni flow, which can lead to crystal defects, if it is sufficiently large. 

Various thermal hydrodynamic phenomena are analyzed, which are related to the dependence of the surface tension coefficient on temperature. Thermo-gravitational and thermocapillary convection in a fluid layer is studied. The problem of thermocapillary drift of a drop in an external temperature-gradient field is considered, as well as other, more complicated problems. 

Figure 18.55 shows the predicted steady-state temperature and meridional flow streamlines for (a) no melt convection and stationary crystal, (b) no crystal rotation with buoyancy-induced melt flow, (c) modest rotation and mixed melt convection, and (d) high rotation rates with mixed melt convection [213], The emissivity of the crystal-vapor interface of the system was specified to be 0.3, while the melt-crystal interface emissivity was set to 0.9 for the GGG crystal of refractive index 1.8. Additional property values and geometric details are listed elsewhere [215]. The crucible diameter is 200 mm, the crystal diameter is 100 mm, and thermocapillary convection was not included in the analysis. 

Schwabe, D. Scharmann, A. Microgravity Experiments on the Transition from Laminar to Oscillatory Thermocapillary Convection in Floating Zones COSPAR, Advances in Space Research Pergamon Press, to be published in 1984. 

Buffone, C., Sefiane, K. Investigation of thermocapillary convective patterns and their role in the enhancement of evaporation from pores. Int. J. Multiphase Flow 30,1071-1091 (2004)... 

Buffone, C., Sefiane, K., Christy, J.R.E. Experimental investigation of self-induced thermocapillary convection for an evaporating meniscus in capillary tubes using microparticle image velocimetry. Phys. Fluids 17, 052104 (2005)... 

Hauser, M. J. B. Simoyi, R. H. 1994b. Inhomogeneous Precipitation Patterns in a Chemical Wave. Effect of Thermocapillary Convection, Chem. Phys. Lett. 227, 593-600. 

Cowley S.J. and Davis S.H. (1983). Viscous thermocapillary convection at high Marangoni number. J. Fluid Mech., 135, 175-188. 

Regnier V.C. and Lebon G. (1995). Time-growth and correlation length of fluctuations in thermocapillary convection with surface deformation. 

T. Azami, S. Nakamura, and T. Hibiya, 2001, Effect of o gen on thermocapillary convection in a molten silicon column under microgravity , J. Electrochem. Soc. 148, G185-G189. 

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