A high color purity red emitting phosphor CaYAlO4:Mn4+ for LEDs

An intense red phosphor, CaYAlO 4 :Mn 4+ , was developed by solid state reaction. The photoluminescence excitation and emission spectra, concentration effect, thermal-dependent luminescence quenching properties and decay curves are investigated. The results show Mn 4+ ion exhibits a broadband excitation extending from 250 to 550 nm and emits an intense red light at 710 nm with high color purity and stable chromaticity coordinates. These results demonstrate that Mn 4+ ion can play a role of activator in narrow red emitting phosphor potentially useful in UV (~370 nm) GaN-base or Blue (~460 nm) InGaN-base LED.