Because copper is easily oxidized in the air, the oxide layer of copper has a great influence on welding. It is easy to form false welding and virtual welding, and in serious cases, the welding plate and components cannot be welded. Because of this, there will be a process when PCB is manufactured, a layer of material will be coated on the surface of the plate to protect the plate from oxidation.
At present, the PCB surface treatment process of domestic plate manufacturers includes: tin spray (HASL, HotairSolderLEVELING), tin deposition, silver deposition, OSP(anti-oxidation), chemical deposition (ENIG), electroplating and so on. Of course, there are also some special PCB surface treatment processes coming with like this.
Comparing different PCB surface treatment technology, their cost is different, of course, the situation is different, only don't choose the right, there is no perfect PCB surface treatment to suit all application scenarios (here is cost-effective, at the lowest price they can satisfy all of the PCB application scenario), so just can have so many process to let our choice, each process is different, of course, there is reasonable, the key is we want to know they use them well.