Evaporation kinetics and composition of CdSe crystals during annealing in vacuum

Using CdSe crystals as an example, the regularities of variation in the dynamically equilibrium state of the crystal have been studied in particular in its composition, with variations in temperature. It is shown that each temperature of warming up of a CdSe crystal in a vacuum is associated with a definite, non-stoichiometric (toward an excess of Cd), reversibly varying dynamically equilibrium composition. An excess of Cd in the CdSe crystal is probably realized in the form of vacancies of Se. A change in the ratio of evaporation rates of Cd and Se2 (with a change in crystal temperature) exerts a strong effect on the electrophysical properties of CdSe films obtained by condensation from the vapour phase