Solution Technique Flux Growth

FIGURE 29.15 Flux growth of emerald (a) schematic (b) emeralds. 

In addition to their importance in jewelry, diamonds also have important industrial applications such as in diamond-impregnated cutting tools and as abrasives. The world use of diamonds is about 261 (26 Mg) per year, of which about 161 is synthetic. The synthetic diamond industry is a 1 billion/year business. 

---

Solids such as KF, PbO, PbFj and BjOj are powerful solvents (flux) in the molten state for many inorganic substances and hence can be used as media for the growth of crystals. The usual technique is to dissolve the solute in a suitable combination of flux... 

The nonlinear optical oxide crystals recently developed are grown by flux (and hydrothermal solution for KTP) techniques to prevent decomposition (KTP, KTA, LBO) or to obtain a low temperature phase (BBO). The intrinsic nonstoichiometry and the impurity contents of the as-grown crystals is determined by the solutions and temperatures used for growth. The intrinsic defect concentrations in these materials are relatively low, compared to the more traditional nonlinear optical oxides having the... 

Brice, J.C. (1986) Crystal Growth Processes, Blackie, Glasgow. A clear description of aU the major (and most of the minor) techniques used to produce single crystals and a useful discussion on method selection. Elwell, D. and Scheel, H.J. (1975) Crystal Growth from High Temperature Solutions, Academic Press, New York. An excellent place to look for fluxes for crystal growth. 

Fig. 22. A brief classification of R123 crystal growth techniques on a basis of different phenomena taking place at various interfaces between solid, liquid and gaseous phases participating in the solidification process (a) possible interface boundaries and phenomena connected with the presence of such interfaces (b) different interfaces present in the self-flux method note that numbers in brackets correspond to the general scheme of classification (a) (c) a number of interfaces and phenomena of some importance for the unidirectional solidification method note that (crystal-high-temperature phase and melt-high-temperature phase) interfaces are close to each other (d) different interfaces and phenomena to be considered in the SRL-CP pulling technique of bulk crystal production note that solute transport and nudeation can be controlled in order to achieve a desired morphology of the crystal.

---