Growth stability of zinc selenide bulk crystals from solutions

The limitation of ZnSe bulk solution growth by the formation of solvent inclusions at high growth rates is investigated both theoretically and experimentally in terms of the ratio V/G of growth rate to temperature gradient. Far the solvents Se, Zn, ZnCl2, PbCl2 and PbSe the V/G-ratio is calculated using Mullins' stability criterion. THM experiments employing PbCl2 and PbSe resulted in the formation of inclusions containing other stable phases than ZnSe. THM growth with Se as a solvent encounters experimental difficulties due to the considerable vapor pressures. The results indicate a discrepancy between experiments and calculation, the experimental V/G-ratio for stable growth being at least one order of magnitude smaller. This deviation is explained by the effect of convection and formation of boundary layers on growth stability. Implications for the growth from Se solutions are given. (C) 1998 Elsevier Science B.V. All rights reserved.