Solder Mask Is the Layer of Copper Protection
After copper plating and PTH process, outer layer trace is following as the next step. However, outer layer trace shares the same process of inner layer trace. For understanding more, please read below article.
https://www.explus.com.tw/faq/What-Are-The-Steps-of-PCB-Inner-Layer-Process.html
After all copper trace is done, we have to protect copper trace from oxidation. And that is what solder mask is printed on PCB for.
Similar to lamination, PCB manufacturer scrubs the PCB surface and then applies micro-etching to increase the adhesion when solder mask ink is printed on the surface. After printing solder mask ink, curing is applied to solidify the ink as the copper trace protection layer.
Green solder mask may be the most common color you can see on PCB. However, do you know what different colors of solder mask that are applied on PCB?
https://www.explus.com.tw/faq/What-Are-The-Steps-of-PCB-Inner-Layer-Process.html
After all copper trace is done, we have to protect copper trace from oxidation. And that is what solder mask is printed on PCB for.
Similar to lamination, PCB manufacturer scrubs the PCB surface and then applies micro-etching to increase the adhesion when solder mask ink is printed on the surface. After printing solder mask ink, curing is applied to solidify the ink as the copper trace protection layer.
Green solder mask may be the most common color you can see on PCB. However, do you know what different colors of solder mask that are applied on PCB?