2024-01-13
Challenges for COB packaging
Challenges for COB packaging
1, the one-time pass rate of the packaging process.
COB package because of its characteristics, COB package is to be on a large board, the board has a maximum of 1024 lights, SMD if the seal is broken, only need to change one on the line, but COB package of 1024 lights after the completion of the package, to test, all lights confirmed that there is no problem, before sealing. How to ensure that the whole board of 1024 lights are completely intact, a pass rate is a very big challenge.
2. One-time pass rate of finished products.
The COB product is to seal the lamp first, after sealing the lamp, the IC driver device should be reflow processing, how to ensure that the lamp surface in the reflow processing, the high temperature of 240 degrees in the furnace will not cause damage to the lamp. This is another big challenge. Compared with SMD, COB saves the processing of over-reflow on the lamp surface, but the device surface needs to be over-reflow as well as SMD, that is, SMD needs to be reflow twice. The difference is that when SMD is over-reflow, the temperature in the furnace will cause two kinds of damage to the lamp surface, one is the welding wire, the temperature is too high. It will expand rapidly, causing the filament to break, the second is the heat in the furnace through the four pins of the support quickly transferred to the wick, the wick may cause small fragmentation damage, this damage is very deadly, detection is often difficult to find, including aging test is difficult to detect, but the crystal of this small damage subtle cracks, after a period of time
Use, this drawback will be highlighted, and then lead to the failure of the lamp. COB is to ensure that when the lamp surface is reflow welded, the high temperature in the furnace does not cause damage to it and ensure the yield, which is also a very important level.
Use, this drawback will be highlighted, and then lead to the failure of the lamp. COB is to ensure that when the lamp surface is reflow welded, the high temperature in the furnace does not cause damage to it and ensure the yield, which is also a very important level.
3, the whole lamp maintenance.
For the maintenance of COB lights, professional repair and maintenance is required. One of the biggest problems with single lamp maintenance is that after repair, there will be a circle around the lamp, repair a lamp, and the surrounding circle will be smoked by the welding torch, and the maintenance difficulty is relatively high.
There are challenges that need to find out the corresponding solutions, at present, COB packaging in the packaging and maintenance process of the problems encountered, the company has come up with the corresponding solutions, such as when the lamp surface reflow, using a certain way to protect the lamp surface, reduce damage; In the maintenance process, point-by-point correction technology is used to ensure the consistency between the lamp beads.
There are challenges that need to find out the corresponding solutions, at present, COB packaging in the packaging and maintenance process of the problems encountered, the company has come up with the corresponding solutions, such as when the lamp surface reflow, using a certain way to protect the lamp surface, reduce damage; In the maintenance process, point-by-point correction technology is used to ensure the consistency between the lamp beads.
4,Fourth, the development trend of COB packaging
One advantage of COB packaging is that it is directly packaged on the PCB board and is not limited by the lamp beads, so, for COB, the point spacing is not scientific, in theory, COB packaging wants to achieve high-density, it is very easy. To borrow a word from the industry, COB packaging is tailored for small spacing.
Oreda marketing director Yang Rui said, "COB does not take the conventional screen route, so that the product will lose meaning, COB is mainly used in the small pitch display, the current small pitch display in the field of security has more use, so COB display a main application field is security."
Hu Zhijun, deputy general manager of Wei Qiaosun Optoelectronics Co., LTD., also expressed the same view, "SMD needs to solve the problem of welding feet, a lamp bead has four welding feet, then with the higher density of the display screen, the lamp beads used in the unit square meter will be more and more, the welding foot will be more and more dense, this problem is not solved, for the table sticker miniaturization is a very big challenge," The COB bypassed the bracket part, and the problem of millions of solder joints was eliminated, so it was easier to miniaturize."
"A feature of COB packaging is to be able to solve the problem of outdoor protection, Wei Qiaoshun adopted a 'rural encircling the city' strategy, the first development of outdoor small spacing, for COB, even to P3, P2.5, P1.8, it is easy to achieve, so Wei Qiaoshun intends to seize the time, seize the opportunity, first break through the outdoor small spacing, Use the advantages of high reliability to penetrate into the field of indoor small space." This is Hu Zhijun's blueprint for the future.
"We think that COB has very good prospects for development, because the reliability of COB products is much higher than that of surface paste products, which is the first point; They are enough to sustain COB into a better future.
"For COBs, there is no limit to lamp beads. Anything below 1.0 can be done easily, but the resulting product will lose its meaning and value without a market. COB display is the hope of the future, but it will take some time for this road to go smoothly. More work is needed to solve the consistency problem. COB is a very good development. Because the price of the two is similar, but the cost of COB is about 15% lower, one is the process problem, to eliminate several process processes, and the other is to achieve mass is easier."
Oreda marketing director Yang Rui said, "COB does not take the conventional screen route, so that the product will lose meaning, COB is mainly used in the small pitch display, the current small pitch display in the field of security has more use, so COB display a main application field is security."
Hu Zhijun, deputy general manager of Wei Qiaosun Optoelectronics Co., LTD., also expressed the same view, "SMD needs to solve the problem of welding feet, a lamp bead has four welding feet, then with the higher density of the display screen, the lamp beads used in the unit square meter will be more and more, the welding foot will be more and more dense, this problem is not solved, for the table sticker miniaturization is a very big challenge," The COB bypassed the bracket part, and the problem of millions of solder joints was eliminated, so it was easier to miniaturize."
"A feature of COB packaging is to be able to solve the problem of outdoor protection, Wei Qiaoshun adopted a 'rural encircling the city' strategy, the first development of outdoor small spacing, for COB, even to P3, P2.5, P1.8, it is easy to achieve, so Wei Qiaoshun intends to seize the time, seize the opportunity, first break through the outdoor small spacing, Use the advantages of high reliability to penetrate into the field of indoor small space." This is Hu Zhijun's blueprint for the future.
"We think that COB has very good prospects for development, because the reliability of COB products is much higher than that of surface paste products, which is the first point; They are enough to sustain COB into a better future.
"For COBs, there is no limit to lamp beads. Anything below 1.0 can be done easily, but the resulting product will lose its meaning and value without a market. COB display is the hope of the future, but it will take some time for this road to go smoothly. More work is needed to solve the consistency problem. COB is a very good development. Because the price of the two is similar, but the cost of COB is about 15% lower, one is the process problem, to eliminate several process processes, and the other is to achieve mass is easier."
