There are three common methods to deal with via holes in PCB boards:Tenting vias,Plugged vias and Vias not covered. Next, let Grande introduce to you what the meaning of Plugged vias in the PCB board manufacturing process is.
The production reason of Plugged Vias
Plugged vias is to guide the hole inside the through-hole with ink for plugging production, and the emphasis is on the quality and denseness of the plugging hole. The processing inspection standard of plugged vias is to be opaque, and the top must be covered and blocked with ink. The next is that the hole must not appear yellowing, and it must not be stained with tin.
Plugged vias process is an important supplement to Tenting vias, generally high-quality PCB boards will require made plugged vias .Plugged vias, first over hole full plugging ink, plugging holes can not let the translucent block over hole, so that the ink on the solder resist ring, will not flow into the over hole, so as to achieve the effect of not appearing over hole yellowing. The smaller the holes the easier to plug, the plug holes is not easy to be too large, the best is maximum 0.5mm, if more than 0.5mm, it is better to choose tenting vias.
The Over-hole is usually used for inter-layer conduction role. So to avoid the board use with short circuit and other situations, usually choose to do Tenting vias. Both to ensure the electrical performance, but also to avoid the risk of short circuit with other components during use. If some PCBs need over-hole as a test point or heat dissipation, it will do Vias not covered.