Vapor growth of typical II-VI wide-gap semiconductor crystals directly from the constituent elements

Three ZnE (E   =   Se, Te) single crystals were successfully grown directly from Zn-E (E   =   Se, Te) system with the assistance of I 2 or NH 4 Cl as the transport agents via a modified chemical vapor transport (CVT) method by avoiding the kinetics limitations of the congruent sublimation of ZnE compound. As-grown ZnE crystals exhibit different crystalline appearance due to various growth conditions. The structure, growth habit and morphologies of as-grown ZnE crystals are investigated by XRD , RO-XRD, SEM and optic microscope. ZnE crystals with NH 4 Cl transport agent look like the platelets with an interesting growth habit, while ZnE crystal with I 2 transport agent has high crystalline quality with a conical shape. Contrasting investigation between different growth results offers us an opportunity to understand the vapor-free-growth mechanism of ZnE crystals in closed-space CVT system, indicating that the free-growth habit of ZnE crystals depends on the growth parameters, which can be essentially attributed to their growth mechanism and the main vapor–solid reactions on the interfaces.