Abstract: A device with a ITO/SiO2/ZnSe/SiO2/Al structure was deposited by electron beam evaporation.Blue-green electroluminescence of ZnSe film,which does not appear in the traditional sandwich structure,was observed.The dependence of emission on applied voltage and frequency were studied in detail.The luminescence mechanism of the device was discussed.It is thought that original electrons are accelerated in the SiO2 layer where they obtain energy and bombard the ZnSe molecules.The electrons in the valence band of the ZnSe are excited to the conduction band.The excited electrons transit back to the valance band or the defect energy level and give emission.This mechanism is called solid state cathodoluminescence because the electrons accelerate in the solid but not in the vacuum.This phenomenon can provide a new way to realize blue inorganic electroluminescence.

Key words: ZnSe, blue, electroluminescence, solid state cathodoluminescence