METHOD FOR OBTAINING FINELY-DISPERSED RED LUMINESCENT MATERIAL FOR THE PRODUCTION OF RESULTING WHITE LIGHT IN LIGHT-EMITTING DIODES

摘要

The invention relates to the chemical industry and can be used for producing resulting white light in light-emitting diodes. The following dry powders, in their basic form, are mixed in a gas-filled vacuum glovebox by way of repeated screenings in a neutral atmosphere: calcium nitride Ca₃N₂, strontium nitride Sr₃N₂, aluminium nitride AlN, silicon nitride Si₃N₄ and europium fluoride, in a stoichiometric ratio in order to obtain a compound with the common formula Ca_1-x-ySr_xEu_yAlSiN₃, where x =0.68-0.97; y=0.0009-0.027. Ammonia chloride and barium fluoride are added to the obtained mixture, in excess of stoichiometry, in quantities of 3-5% by weight of the total mass of charge material, in the ratio 1:1. After that, the mixture of powders is loaded into an alundum crucible, and placed in a vacuum oven where sintering is carried out in a forming gas at a temperature of 1700°C, at a heating rate of 4-5°C per minute. Said mixture is held for 3 hours at a temperature of 1700°C. The average size of particles of the obtained luminophore is 7-11 microns, the monodispersity coefficient is 0.8-0.9. The luminous intensity, at an excitation radiation wavelength of 450-460 nm, is 95-97%.