A Y _3Al _5O _(12):Ce ~(3+) (YAG:Ce ~(3+)) phosphor was successfully prepared by a modified impinging stream (IS) method at a temperature of 1200°C. The as-obtained sample has perfect crystallinity, uniform morphology and good dispersion due to the added size classification (SC) process and low-temperature calcination. The mechanism of YAG:Ce ~(3+) crystal growth was proposed based on the results of scanning electron microscopy and x-ray diffractometry, which agreed with the Ostwald ripening process. The excitation and emission spectra revealed that the excitation band distributes between 310nm and 520nm and peaks at 342nm and 460nm, and the emission band covers from 470nm to 650nm and centres at 532.5nm, respectively. White light can be obtained from the fabricated light-emitting diodes using the prepared phosphor, and the CIE coordinate, correlated colour temperature and luminescence efficiency are (0.312, 0.321), 7560K and 80.7lmW ~1, respectively. All the results indicated that the modified IS method is a promising way to prepare the YAG:Ce ~(3+) phosphor, and SC process is effective in producing the phosphor with uniform morphology, ideal size and size distribution. This method has a broad industrial prospect in phosphor manufacture.
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