Luminescence of ZnS and ZnSe Window and Filter Materials

The visible and infrared cathodoluminescence spectra of undoped polycrystalline and single-crystal ZnSe and ZnS have been measured at 295, 78, and 10 K. Infrared luminescence bands were detected at 1.8, 2.4, 3.2, and 3.8 pm in IRTRAN 4 (ZnSe) and single-crystal ZnSe, but not in Raytran ZnSe. Similarly, bands at 1.4, 1.6, and 1.9 am were detected in IRTRAN 2 (ZnS) and single-crystal ZnS, but not in Raytran ZnS. The infrared luminescence in ZnSe materials is accompanied by edge emission and the copper red band, in addition to the copper green band appearing in IRTRAN 4. Self-activated luminescence was observed in Raytran ZnSe. The power law decay of the 1.8 and 3.8 pm bands in IRTRAN 4 suggests a bimolecular kinetic reaction. A model is proposed to account for the transitions involved.