ZnS is one of the most popular luminescence material in the electroluminescence(EL)application

and it is the most promising material for the blue EL devices.Because of it's wide energy band gap(3.6eV)and directive transition characteristics

it can be used to fabricate different colour EL devices with whose visible region by doping various impurities.In this paper

ZnS single crystal with high quality grown by chemical vapour transportation with Iodine is described.First

powder ZnS precipitation is purified in Ar and H2S mixed gas at 1100℃ for 10-20 hrs.to improve the stoichiometry and increase the size of the ZnS particals.Then

both purified ZnS and lodjne powder are put jnto a vessel separately.