Immersion silver is a RoHS compliant finish available on any PCB configuration, at no additional cost.
Immersion silver is:
- Less expensive than Electroless-Nickel Immersion Gold (ENIG)
- Safer than immersion tin (for the environment)
- Easier to use than Organic Solder Preservative (OSP)
- Has a more level (planar) surface than hot air surface leveling (HASL)
- Well suited to lead-free assembly techniques
However, immersion silver is more susceptible to temperature and humidity as well as handling. If left exposed to the environment, immersion silver reacts with sulfur from the environment, creating silver sulfide on the surface of the board. Though Silver requires more care in storage and handling than immersion tin, immersion silver is nevertheless an emerging standard as a good, predictable, general purpose non-lead finish.