Luminescence properties of ZnS/porous Si composites

Abstract

ZnS/porous Si composites were obtained by depositing ZnS films on porous Si substrates. The photoluminescence (PL) spectra were measured. The results showed that, excitation wavelengths, growth temperature of ZnS films and preparation current density of porous Si can all affect the PL properties of ZnS/porous Si. The PL spectra were different when excited by the light with different wavelengths, and the relative integrated intensities of ZnS and PS were also different; when ZnS films were grown at different temperatures and porous Si were prepared at different current densities, ZnS/porous Si composites also presented different PL properties. With the increase of growth temperature of ZnS, the luminescence intensity of ZnS increased but the luminescence intensity of PS decreased along with the redshift of the peak; under proper preparing current density of PS conditions, the blue, green emission from ZnS combining with the red emission from PS, a broad PL band in the visible region was obtained, exhibiting intensive white light emission. This work might open up a way to obtain the electroluminescence (EL) of ZnS/porous Si and solid white light emission devices.