Convection in a chemical vapor transport process

Crystal growth of Cu2ZnSnS4 solar cell absorber by chemical vapor transport with I2

“…From a rough estimation of the ampoule pressure for the two cases, this behaviour seems consistent with the predictions of Zuo et al [45] on the transition between a diffusion-dominated to a convection-dominated regime of mass transport. Indeed, the computed Grashof, Schmidt and Rayleigh fluid numbers (Table 2) [23] show that the longitudinal convective share of transport for test No. 3 is about three times higher than for test No.…”

“…The CZTS lattice parameters as from relevant XRD literature are also reported for comparison. For computation of the fluid numbers, the reader is referred to Klosse's work [23]. Table 2: experiments No.…”

“…9. However, according to the analytical model of Klosse et al [23], the mass transport regime should be considered convection-dominated for both these two cases. Furthermore, the Rayleigh numbers exceed 4·10 3 , a value above which a strong deterioration of the crystal quality has been reported by Böttcher et al [25].…”

“…The importance of fluid dynamics in determining the right growth conditions in such systems is well described by the literature [22][23][24][25][26][27][28][29][30][31][32]. The CVT crystal grower will often encounter dimensionless numbers such as the Grashof, Schmidt, Prandtl and Rayleigh numbers that serve for the description of the system, especially with regard to diffusion and convection.…”

“…The CVT crystal grower will often encounter dimensionless numbers such as the Grashof, Schmidt, Prandtl and Rayleigh numbers that serve for the description of the system, especially with regard to diffusion and convection. The interested reader is referred to Klosse's work [23] for a detailed treatment of such aspects. For example, for simple systems it is known that crystallographic perfection is favoured under diffusion-limited transport rate, when nucleation density is minimized [24].…”