Temperature dependence of luminescence in ZnSe

As-grown ZnSe and RbCl- and CsCl-doped ZnSe single crystals are grown by a sublimination method. The temperature dependence of the photoluminescence (PL) spectra in the blue emission region is measured from 4.2 K to 300 K. The emission band is observed in RbCl- and CsCl-doped ZnSe from 4.2 K to 300 K. In as-grown and Zn-annealed ZnSe, the emission band undergoes considerable attenuation at 100 K. However, the emission band is clearly observed in Se-annealed ZnSe up to near room temperature. These results prove that the disappearance of Se vacancies enhances room temperature PL.