Mechanism of zinc oxide single crystal growth under hydrothermal conditions

The growth mechanism of ZnO single crystals is discussed on the basis of th e analysis of ZnO crystal structure and physical-chemical characteristics o f growth media. Polar growth of ZnO single crystals along the C-axis is exp lained taking into account the mechanism of the interaction between negativ ely charged Zn-containing species in the solution and the (0001), (000 (1) over bar) surfaces with different chemical compositions (Zn-flat plane for the face of positive mononedron, O-flat plane for the face of negative mono hedron) and the opposite sign of the charge (close to +2 and -2 respectivel y). Partial substitution of Li+ for Zn2+ leads to decrease the effective po sitive charge of (0001) surface and as a result to decrease the growth rate s in the presence of Li-ion in the starting solution.