Controlled deposition of high grade crystals - involves monitoring volume change of overall liquid and solid system while solution is cooled

摘要

A method for the measurement and control of the solidification of a two phase liquid/solid system is esp. for application in the preparation of high grade crystals by control of the volume of the system. The whole system may be immersed in an inert fluid and the volume changes measured on Archimedes principle, or by the immersion of a partly immersed float in the liquid phase, holding it at a fixed level, and measuring the buoyancy force experienced by it. The measurement signals obtained may be used to control the solidification process, especially in the production of oriented single crystal or by epitaxial deposition on a substrate of appropriate crystalline orientation.