The change in the photoluminescence spectra of Cu-doped ZnSe single crystals caused by heat treatment

Copper has been incorporated into high-purity ZnSe single crystals in the concentration range from 0.005 to 0.5 p.p.m. using the distribution effect during dipping into molten Zn-Cu alloys. The change in the I 1 d emission line reveals that the occupation state of the incorporated Cu atoms can be converted from interstitial to substitutional sites through annealing at 573 K after heat treatment under a saturated Se pressure. It becomes clear that there are two origins, V Zn and Cu Zn , for the I 1 d emission as suggested by Huang and co-workers (1983).