6 Layers Immersion Silver PCB Silver Coating Finish

Immersion Silver, it’s also known as Immersion Ag, it’s produced by the selective displacement of the copper atoms by silver atoms on the exposed copper surface. As an improvement on HASL with more flat surface, the cost of Immersion Ag is more expensive than HASL but less expensive than Immersion Gold.

Immersion Ag is a RoHS compliant finish, and it’s compatible with surface mount, BGA and through hole components. The typical thickness of Imm Ag is 0.1-0.3um and the shelf life is 6-12 months.

The advantages of Immersion Silver

● Absolutely flat
● Good for fine pitch and SMD
● Good for press fit connector’s capability
● Excellent solderability
● Multiple heat cycles during assembly process
● It’s reworkable

The disadvantages of Immersion Silver

● Very sensitive to handling / tarnishing / cosmetic concerns – gloves must be used
● Short operating window between assembly stages
● Not recommended to use peelable masks
● Special packaging required – if packaged opened and not all boards used, it must be resealed quickly
● Reduced supply chain options to support this surface finish

A-TECH offers the surface finish of immersion silver, since this finish is much more sensitive in manufacturing and it’s more susceptible to temperature and humidity than other finishes, we use special operation standards and higher level of packing standards to ensure excellent appearance of immersion Ag.