고상법에 의한 Zn_2SiO_4:Mn^(2+)녹색 형광체의 제조와 특성에 관한 연구

Zn_(2(1-x))Mn_xSiO_4(0.07≦×≦0.15) green phosphor was prepared by solid state reaction. The first heating was at 900℃-1250℃ in air for 3 hours and the second heating was at 900℃ in N_2/H_2(95%/5%) for 2 hours. The size effect of SiO_2 in forming Zn_2SiO_4 was investigated. The temperature for obtaining single phase Zn_2SiO_4 was lowered from 1100℃ to 1000℃ by decreasing the SiO_2 particle size from micro size to submicro size. The effect of the activators for the Photoluminescence (PL) intensity of Zn_2SiO_4:Mn^(2+) was also investigated. The PL intensity properties of the phosphors were investigated under vacuum ultraviolet excitation (147 nm). The emission spectrum peak was between 520 nm and 530 nm, which was involved in green emission area. MnCl_2·4H_2O, the activator source, was more effective in providing high emission intensity than MnCO_3. The optimum conditions for the best optical properties of Zn_2SiO_4:Mn^(2+) were at x = 0.11 and 1100℃. In these conditions, the phosphor particle shape was well dispersed spherical and its size was 200 nm.