Self-selecting vapour growth of bulk crystals - Principles and applicability

To date, most SSVG has been done at the <50 g level for research or small scale production use. Prospects for scaling up the growth are considered, there being no barriers identified in principle. However, there is a limitation in that the shape of the grown crystals is not accurately controlled at present. To overcome this, and to offer an alternative method of scaling up, the use of vertical tube systems is explored. A significant additional advantage of the vertical configuration is that it allows for continuous recycling of the source/crystal mass so as to continuously self-refine the increasingly uniform - and crystalline - product. Achievements to date in growing II-VI and IV-VI crystals are described for prototype vertical SSVG systems. Finally, future prospects for the SSVG method in terms of further developments to the method, and the specific materials that will benefit from it are highlighted.