Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12 : Ce3+ phosphor for white light emitting diodes

We have developed a new oxide-based phosphor Ca3Sc2Si3O12:Ce3+, which is applicable as a green-emitting color converter for white light emitting diodes (LEDs). This phosphor absorbs blue light around 450 nm and emits green luminescence, with a peak wavelength around 505 nm. It is a promising candidate for application in LEDs as quenching of the phosphor at 150 C was smaller than that of Y3Al5O12:Ce yellow phosphor. A white LED with high color rendering was fabricated by combining this phosphor with a blue GaN LED and a red phosphor. The luminescence of this phosphor is derived from the 5d-4f transition of the Ce ion and the luminescence decay curve fit a single exponential function. This phosphor has a garnet-type host crystal structure. X-ray absorption fine structure analysis showed that Ce ions replaced the Ca position of the host crystal as Ce3+. (c) 2006 The Electrochemical Society.