Light-emitting diode (LED) full-color chip on board (COB) mode packaging method

Abstract

The invention discloses a light-emitting diode (LED) full-color chip on board (COB) mode packaging method. The LED full-color COB mode packaging method is characterized in that the LED full-color COB mode packaging method comprises a substrate, a circuit arranged on the substrate, LED light emitting chips, and a packaging glue for the LED light emitting chips, wherein the circuit comprises a front surface circuit arranged on the upper surface of the substrate and a back surface circuit arranged on the back surface of the substrate, and the LED light emitting chips are placed on the front surface circuit; the LED full-color COB mode packaging method mainly includes the following steps of substrate cleaning, die bonding primer unfreezing, uniform expansion of distances among the LED chips, attachment of the LED chips to the substrate through a die bonder and a die bonding primer, connection of the LED chips attached to the substrate with a bonding pad on the substrate through a bonding wire and a welding wire machine, and compression molding of a packaging glue and the front surface of the substrate through a die manufacturing machine under a high temperature to protect the LED chips on the substrate. According to the LED full-color COB mode packaging method, the problem of uneven light emitting caused by a light mixing phenomenon existing after an application end is lighted in original COB packaging processes is solved, so that reliability and property of an indoor display screen can be improved, service life of the indoor display screen is prolonged, and the method is further application to outdoor display screens.

Description

technical field [0001] The invention relates to the technical field of LED packaging, and more specifically relates to a packaging method of LED full-color COB mode. Background technique [0002] With the continuous improvement of indoor display application technology, the currently used display application products such as projection / DLP / LCD / PDP cannot fully meet the market application requirements. There are also some defects in various aspects so that it cannot break through the development of technology. [0003] The main defects of the current projection display: 1. The light point design of the front projection fusion splicing needs to be very precise. The geometry will change a lot, and professional re-calibration is required; 2. Rear projection fusion splicing needs to provide a large darkroom space, and front projection fusion splicing requires no people to walk in front of the screen to prevent blocking the projection light path; 3. Fusion belt "Eat" the pixels i...

AI Technical Summary

Problems solved by technology

[0003] The main defects of the current projection display: 1. The light point design of the front projection fusion splicing needs to be very precise. The geometry will change a lot, and professional re-calibration is required; 2. Rear projection fusion splicing needs to provide a large darkroom space, and front projection fusion splicing requires no people to walk in front of the screen to prevent blocking the projection light path; 3. Fusion belt "Eat" the pixels in the overlapping part, and the full screen resolution cannot achieve standard resolution splicing; 4. The requirements for ambient lighting are high, and the environment directly shining on the screen will seriously affect the display effect; 5. After long-term use, due to the brightness of the projector, Inconsistent color attenuation causes obvious fusion bands, which seriously affects the display effect

[0004] Defects of DLP splicing display: 1. After using for a certain period of time, there will be obvious color and brightness differences between screens, commonly known as "patching" phenomenon, which seriously affects the display effect; Obvious "row brightness reduction" phenomenon; 3. The brightness in front of the screen is low, and it is greatly affected by the ambient light, and the glass screen is easy to form a more obvious reflection phenomenon; 4. The unit consistency is poor, and the patchwork is easy to match The confusion of the table separation lines leads to misreading and misjudgment of the content

[0005] Defects of LCD / PDP splicing display: 1. When used in large-scale conferences or video conferences, the characters will be clearly divided by the splicing seams, which seriously affects the display effect

2. After using for a period of time, dark edges and black corners of the display will appear, and there will be differences in color and brightness between screens, and the recovery cannot be adjusted

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