LED packaging method

Abstract

The invention relates to an LED packaging method. The method comprises steps: a cooling substrate (21) is prepared; an LED chip is prepared; a first lens layer (22) is formed on the upper surface of the LED chip; a first packaging layer (23) is formed on the upper surface of the LED chip and above the first lens layer (22); a second lens layer (24) is formed above the first packaging layer (23); asecond packaging layer (25) is formed above the second lens layer (24), and the second packaging layer (25) contains phosphor; and the LED packaging structure provided with the first lens layer (22),the first packaging layer (23), the second lens layer (24) and the second packaging layer (25) is subjected to long roasting to complete packaging of the LED. Through forming multiple layers of hemispherical lenses, the light beams are more concentrated and can perform uniform irradiation, the light extraction efficiency is improved, increasing of extra lenses is avoided, and the production costis reduced.

Description

technical field [0001] The invention belongs to the technical field of optoelectronic devices, and particularly relates to an LED packaging method. Background technique [0002] At the end of the last century, the breakthrough of III-V compound semiconductors represented by GaN-based materials in the field of blue light chips brought about a lighting revolution, which was marked by high-power light-emitting diodes (Light-Emitting Diodes, LEDs). Semiconductor lighting technology (Solid State Lighting, SSL) for the light source. [0003] At present, LEDs mostly use GaN-based blue chips and yellow phosphors to generate white light to achieve illumination, but this method has the following problems. [0004] First of all, because the light emitted by the LED light source generally has a divergent distribution, that is, a Lambertian distribution, which causes the illumination brightness of the light source to be insufficiently concentrated, and generally requires secondary shapi...

AI Technical Summary

Problems solved by technology

[0004] First of all, because the light emitted by the LED light source is generally distributed in a divergent manner, that is, the Lambertian distribution, this causes the illumination brightness of the light source to be insufficiently concentrated, and generally requires secondary shaping through an external lens to meet the lighting needs of specific occasions, which increases production costs.

Secondly, phosphor powder is generally directly coated on the surface of the chip, and due to the light scattering characteristics of phosphor powder, a considerable part of the forward incident light will be back scattered, so the chip has an absorption effect on the back scattered light. Therefore, this direct coating method will reduce the light extraction efficiency of the package

In addition, the high temperature generated by the chip will significantly reduce the quantum efficiency of the phosphor, which seriously affects the lumen efficiency of the package

Again, when the LED chip is working, it will generate a lot of heat. If the temperature is too high, it will lead to a series of problems such as reduced light intensity, spectral shift, increased color temperature, increased thermal stress, and accelerated aging of the chip, which greatly reduces the use of LEDs. life

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