Crystal growth and epitaxy from solutions I. Fundamentals of growth from solutions

Crystal growth from aqueous solutions, organic solutions, and high-temperature solutions is widely used for preparation of samples for research, also to prepare new phases for exploratory research. Furthermore, there are a few crystals which are grown to a large size on a technological scale. In this lecture an attempt is made to present a few fundamental aspects of crystal growth from solutions which are of relevance for the practical crystal grower. Firstly the concepts of solutions are presented in order to find suitable solvents of sufficient solubility and minimum contamination of the crystals. Then we have to understand nucleation and growth mechanisms in order to control the formation of nuclei so that large crystals may be obtained, and to adjust the growth mode and surface morphology for achieving homogeneous crystals of high structural perfect-ion. Lastly growth from solutions is often limited by diffusion : the understanding of the role of hydrodynamics allows us to derive experimental conditions for the maximum stable growth rate, i.e. to grow large inclusion-free crystals at the highest possible growth rate.