Intrinsic LiNbO₃ melt species partitioning at the congruent melt composition II. Dynamic interface case

Crystal growth from a stirred melt is discussed by considering the relationship of a phase diagram partition coefficient, k^j₀, and its effective partition coefficient, k^j_E, for all of the seven LiNbO₃ intrinsic species. Here, the interface electric field become s an extremely important variable for the crystallization process. The causes of these electric fields, i.e., the thermoelectric power and the charge separation effects (crystallization EMF), are a function of growth velocity, V, temperature gradient, G_L, and solute boundary layer thickness, δ_C. Additionally, the chemical conversion reactions in the melt are taken into account. The above considerations eventually lead us to discuss conditions for the dynamic congruent-state growth of LiNbO₃ via the Czochralski technique and to set up the most appropriate congruent composition for each bulk crystal growth condition from a finite amount of melt, 1-g. For the best congruent-state growth, one must find an appropriate combination of δ_C(g), V(g) and G_L(g) which satisfies the conditions that, as much as possible, lead to a crystal with approximately constant composition.