백색 LED용 ZnS:Mn,Cu 황색형광체의 발광특성

Abstract

ZnS:Mn yellow phosphors doped with Cu for white light emitting diodes were synthesized by solid state reaction method. The optical properties and structures of ZnS:Mn,Cu phosphors were investigated by x-ray diffraction, photoluminescence, and scanning electro microscopy. Photoluminescence excitation spectra originated from <TEX>$Mn^{2+}$</TEX> were ranged from 450 nm to 500 nm. The yellow emission at around 580 nm was associated with <TEX>$^4T_1{\rightarrow}^6A_1$</TEX> transition of <TEX>$Mn^{2+}$</TEX> ions in ZnS:Mn,Cu phosphors. The highest photoluminescence intensity of the phosphors under 405 nm excitation was obtained at Cu concentration of 0.02 mol%. The enhanced photoluminescent intensity in the ZnS:Mn,Cu phosphors was interpreted by energy transfer from Cu to Mn.