Fabrication method for white-light LED bead by ultraviolet stimulation of perovskite fluorescent powder

Abstract

The invention discloses a fabrication method for a white-light LED bead by ultraviolet stimulation of perovskite fluorescent powder. White fluorescent powder is of a perovskite structure and can be stimulated by ultraviolet light with relatively short wavelength to give out white single-phase fluorescent powder, the light-emitting intensity is high, and the problems of defect and low light effectbrought by mixed blending of fluorescent powder are solved. The fabrication method is simple and is low in cost and small in energy consumption; the white fluorescent powder is stable in chemical property and relatively good in humidity resistance and has relatively good light attenuation consistency, the perovskite has high light-emitting efficiency, the light color adjustability is relatively high; the single-phase fluorescent powder is used for fabricating the white-light LED bead, the gamut value of the back-light bead is greatly improved, the simulation efficiency is high, the concentration of the fluorescent powder during the package operation process is relatively low, and the package operation difficulty and the rejection ratio of the product are reduced; the fluorescent powder andpackage glue are uniformly mixed by an organic solvent, failure agglomeration is prevented, and the quality of the white-light LED bead is improved; and by vacuum defoamation, toxicity of the organicsolvent is prevented, and the reliability of a white-light LED is improved.

Description

technical field [0001] The invention relates to the technical field of white light LED lamp beads, in particular to a method for preparing white light LED lamp beads with ultraviolet-excited perovskite phosphor powder. Background technique [0002] In recent years, with the gradual reduction of luminous efficiency and cost of light-emitting diodes, semiconductor lighting has gradually become the development trend of modern lighting. For "21st Century Green Light Source". [0003] At present, the main methods for obtaining white light from GaN-based LEDs are: blue LED + yellow phosphor powder, three-color LED synthetic white light, and purple LED + three-color phosphor powder. Commercially available white LEDs use GaN-based LED chips emitting 450-470nm blue light and surface-coated blue light-excited yellow-emitting phosphors, mainly cerium-doped yttrium aluminate phosphors. This commercial phosphor also has some disadvantages, mainly poor color saturation and instability o...

AI Technical Summary

Problems solved by technology

[0005] Using ultraviolet LED as the excitation source with red and blue phosphors to prepare white LEDs, due to the radiation reabsorption between phosphors of different substrates, it will increase energy loss and reduce luminous efficiency, so single-phase phosphors excited by ultraviolet LEDs have become the mainstream development. Trend; There are many reported UV LEDs to excite single-phase phosphors, such as the Chinese invention patent of application number CN106929011A, which provides a method for preparing white LED lamp beads for UV-excited perovskite phosphors, whose general chemical formula is M 1-x-y-z SM x Tb y T m z AlSiN 3-2(x+y+z) / 2 , wherein: M is at least one of Ca, Sr, and Ba, 0.001≤x≤0.2, 0.001≤y≤0.1, 0.001≤z≤0.2, and the white light phosphor can emit White light with short excitation wavelength and wide excitation spectrum