From a quality point of view, when selecting the PCB board process, the resin plug hole is good, but for the entire process flow, there is one more process. In terms of cost, the cost of the PCB board resin plug hole is greener than that of the PCB board. The oil plug hole is much higher, and the green oil plug hole is simple for the whole process and can be operated together with the surface ink in the combined clean room. Or the plug hole is printed first, but the quality of the plug hole is not as good as the resin plug hole. The green oil plug hole shrinks after being fixed, which is not very suitable for customers with high requirements or design requirements.
When the PCB board uses resin plug holes, this process is usually due to BGA parts, because traditional BGA may make VIA between PAD and PAD to the back of the wiring, but if the BGA is too dense and the VIA cannot go out, you can directly go from the PAD Drill holes to make vias to other layers to route the wires, and then fill the holes with resin to fill and plate the copper into PAD, which is commonly known as the VIP process (viainpad). If you just do via on the PAD without plugging the holes with resin, it is easy The leakage of tin leads to a short circuit on the back and empty solder on the front.
PCB board resin plugging process includes drilling, electroplating, plugging, baking, and grinding. After drilling, the hole is plated through, then the resin is plugged and baked, and finally, the resin is polished and ground. It does not contain copper, so another layer of copper is needed to turn it into PAD. These processes are done before the original PCB drilling process, that is, the holes of the fortress hole are processed first, and then other holes are drilled. The original normal manufacturing process went.
Generally, the green oil window is the through-hole, that is, the plug-in hole with a diameter of 0.35MMC or more. Because it is used for plug-ins, there can be no insulating green oil in the hole. The green oil plug hole part is mainly for the subsequent BGA PCB multi-layer circuit board motherboards in the SMT production to plug the holes and the NPTH holes with a diameter below 0.35MMC. The reason for the plug holes is to prevent these non-part holes from being natural for many years. In the environment, it will cause a short circuit after being oxidized and corroded by acid and alkali, causing poor electrical properties, so plug holes should be made. The standard for BGA plug holes is opaque, and it is best to fill up two-thirds of the hole, but the ink cannot pack the hole after the plug hole. Some customers with BGA require plug holes.
The resin plug hole and the green oil plug hole of the PCB board are mainly different in fullness. In other aspects, such as acid and alkali resistance, the resin plug hole has an advantage over the green oil.
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