Improved output coupling efficiency of a ZnS:Mn thin-film electroluminescent device with addition of a two-dimensional SiO2 corrugated substrate

We present a study of the effects of adding a two-dimensional (2-D) SiO2 corrugated substrate onto a ZnS:Mn thin-film electroluminescence (EL) device on its EL properties. Two-step irradiated hologram lithography and reactive ion etching were used to fabricate a 2-D square-lattice-dotted pattern of SiO2 on the glass substrate. The addition of this corrugation leads to a 220% enhancement in the EL efficiency at 40 V above the threshold voltage under a 500-Hz sinusoidal excitation. This improvement in the output coupling efficiency is due to the diffraction scattering produced by the 2-D SiO2 periodic corrugations.