The effects of substrates and deposition parameters on the growing and luminescent properties of Y3Al5O12:Ce thin films

YAG:Ce (Ce doped Y3Al5O12) phosphor thin films were deposited by rf magnetron sputtering on quartz and sapphire substrates. The effects of sputtering parameters, annealing conditions, and substrates on the crystallinity and the luminescent properties were investigated. Oxygen partial pressure in sputtering gas strongly contributed to the crystallinity and atomic ratio of Al/Y, and the luminescent properties of YAG:Ce films accordingly depended on it. Stoichiometric and polycrystalline YAG:Ce films could be obtained at the gas ratio of 50% oxygen. After annealing process, amorphous YAG:Ce films were not only transformed to crystalline phases, but also activated to exhibit the yellow emission peak at 550 nm with the excitation wavelength of 450 nm. The films deposited on c-plane sapphire substrates exhibited higher PL intensity than those on quartz substrates due to the superior crystallinity.