Chip-grade LED (Light Emitting Diode) packaging device with controllable light emitting angle and packaging process

Abstract

The invention discloses a chip-grade LED (Light Emitting Diode) packaging device with a controllable light emitting angle and a packaging process. According to the LED packaging device, first white wall adhesive layers are arranged on side faces of an LED chip, a diffusion layer and a fluorescent adhesive layer and are used as reflection surfaces; the reflection surfaces with different shapes can be designed aiming at requirements on different light emitting angles, so that the LED packaging device with the controllable light emitting angle is obtained; furthermore, the diffusion layer is arranged between the LED chip and the fluorescent adhesive layer, and the diffusion layer has a refractive index higher than that of a fluorescent adhesive; the difference between the refractive indexes of the LED chip and the fluorescent adhesive layer is reduced; the refractive indexes of the LED chip, the diffusion layer and the fluorescent adhesive layer have a certain gradient and the light emitting efficiency of the LED chip is improved, so that the luminous flux of the device is improved; the refractive indexes of diffusion powder and a packaging adhesive in the diffusion layer are different, and the condition that light emission of blue light of the LED chip is not uniform can be improved, so that the space color uniformity of the device is improved; and the design of a concave groove and white wall structure is adopted, so that the reliability problem of a product is greatly improved.

Description

technical field [0001] The invention belongs to the technical field of LED packaging, and relates to a chip-level LED packaging device, in particular to a chip-level LED packaging device and a packaging process with a controllable luminous angle. Background technique [0002] In recent years, under the trend of global energy saving and emission reduction, LED light sources have developed rapidly. Compared with traditional light sources, LED light sources have the advantages of long life, small size, high efficiency, fast response, shock resistance, energy saving, and no pollution. , is a "green light source", and LED light sources are bound to be used on a large scale. [0003] In the production process of LED light sources, packaging is a key link between the past and the future. The function of packaging is to provide sufficient protection for the light-emitting chip, preventing the chip from being exposed to aging in the air for a long time or being damaged by mechanical ...

AI Technical Summary

Problems solved by technology

This structure has the following problems (1) the large luminous angle is not conducive to the design of secondary optics, and the extraction rate of light is relatively low during secondary optics design; (2) the phosphor is an opaque micron-sized solid particle, which is mixed in glue Among them, at the contact with the surface of the chip, bubbles are easy to form around the phosphor particles, which affects the adhesion between the adhesive layer and the chip, and the phosphor particles have a back reflection effect on light, which affects the extraction rate of blue light and fluorescence, and reduces the light extraction efficiency; The refractive index of the glue in the fluorescent glue is generally 1.4-1.54, while the LED chip sapphire has a refractive index of 1.78. The refractive index difference between the two is large, which is easy to cause full emission of light, thereby reducing the luminous efficiency of the device.

(3) Due to the inconsistency of the light emitted from the side and the front of the chip, it is easy to cause the thickness of the fluorescent adhesive layer to not match the light energy in all directions of the flip-chip chip, and it is easy to cause uneven light color in space

When using solder paste, the residue of flux will affect the light and color parameters of the device and its reliability; when using silver glue as solder, the silver ions migrate along the direction of current during the long-term use of the device, and the silver ions at both ends of the electrode gap Silver whiskers are produced, which is prone to short circuit of the device, which brings great hidden danger to the reliability of the product

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