In the LED production of the problem is the chip package, the cup of bubbles occupy a large proportion of bad, if the production bubble is not well resolved or control, it will cause the product to accelerate the decay of a factor, which will show the IV Decrease, IR becomes larger, VF rises.
Affect the bubble generation factors are more. In the general case, the process is mature, the bad proportion of the bubble will not be too high.
If the cup has bubbles, you can give the cup a certain percentage of glue, and then in the next process.
The following are the relevant factors:
1. The temperature and humidity of the environment have a greater impact on the bubble.
2. The temperature of the mold is also a factor in the generation of bubbles.
3. Bubble generation and process adjustment has a great relationship.
For example, some factories do not have the same vacuum without bubbles, and there is a bubble in this factory even if there is a vacuum, from this point of view should not be pumping the problem of vacuum. But the speed of operation, the problem of skilled.
At the same time with the ambient temperature is inseparable. Environmental temperature changes, we can take the appropriate measures to be controlled. If the room temperature is 15 degrees, we have to think of ways to make the glue temperature reaches 60 degrees, so do the cup bubble should not appear again!
At the same time we have to pay attention to a lot of details. Such as the drum in the plastic when the plastic produced a small bubble under the naked eye and can not see under the microscope, but one into the oven body, thermal expansion bubble expansion. If the temperature is too high at this time, the gas has not jumped on the curing so the bubble phenomenon. LED surface bubble but did not break, this is the glue when the bubble. LED surface bubble but broken, because the temperature is too high.
Before the pre-filling glue, the bracket must be preheated. Preheat pre-irrigation of the AB material for 2 hours exchange time. As long as you keep the AB material, the stent is hot, the bubble problem is not difficult to understand. Because AB cold when the poor mobility, cold bracket easily encountered into the bubble.
Operation should pay attention to the following questions:
1. Operator's operating skills in question (the whole side of which there are bubbles)
2. The speed and glue of the glue machine is not controlled (it is easy to place the bubble)
3. Is the machine clean (this does not cause air bubbles, but it is easy to produce something like ice, especially cyclohexanone)
4 to the stent glue, the drum speed can not be fast.
5. glue to change, clean the drum.
6. Please match the glue from the glue and the speed of the glue to control the glue method there is a problem, but with the adjustment of the glue machine has a certain relationship.