Abstract: A novel photoluminescent material is disclosed comprising an active layer of ZnS.sub.1-x Te.sub.x deposited directly onto a substrate by molecular beam epitaxy. The emitted light is primarily in the blue end of the spectrum. The substrate may be GaAs or more preferably Si. Depositing the material directly onto Si allows the material to be used to manufacture integrated semiconductor light emitting devices. High efficiency may be obtained at low concentrations of Te (0.01.ltoreq.x.ltoreq.0.07) which allow good lattice matching of the active layer to an Si substrate.