1. First consider what surface treatment the circuit board uses. If it is sprayed tin (HA LS, I must prevent the use of single-sided plug hole technology, because the depth of the single-sided plug hole is low, which is easy to cause plugging during tin spraying. Tin beads, plug tin beads have a great influence on the appearance.
2. If the circuit board is treated with other external surfaces, such as immersion gold, OSP, immersion silver, etc., single-sided plug holes can be accepted. After considering the above factors, let's look at the customer's green oil window design. If it is partially opened, it should be Try to prevent the use of green oil cover hole edges and allow green oil to enter the hole, because this method is also easy to cause tin beads.
3. Combining the above two situations, the best treatment is to double-sided plug holes, or green oil cover hole edges, the disposal method that allows 1-2MIL tin rings is the most popular with circuit boards. Of course, the oil plugging situation here is for Ordinary photosensitive oil is not a heat curing oil.
