Sunstone offers the following surface finishes for PCB fabrication to meet a variety of complex needs:
- Immersion Silver — RoHS compliant finish available on all Sunstone PCBs. This "no additional cost" coating that provides a very planar surface and a very reliable solder joint. While this finish is ideal for prototyping as well as larger lot sizes, this coating is more susceptible to temperature, humidity as well as handling. As a result, care should be taken when storing or handling these PCBs
- HASL — Tin-lead solder coating (Hot Air Solder Level). This time tested leaded solder finish is available on all Sunstone PCBs and at no additional cost. Solder provides the most reliable solder joint and shelf life of the available surface finishes. However due to the thickness and application of this coating, it can be less planar and may not be an ideal choice for fine pitch components
- ENIG — (Electroless Nickel / Immersion Gold) RoHS compliant finish provides a very planar surface, a very reliable solder joint and is very resistant to environmental storage conditions, handling etc. ENIG is available on all Sunstone PCBs (except ValueProto ). ENIG provides a great deal of flexibility of applications and is ideally suited for PCBs of many design needs.
- Gold Fingers — Ideal surface finish for a wear application such as an insertion connector. Provides a very planar surface that is resistant to wear from repeated insertions. Gold fingers can be ordered in conjunction with the other surface finishes as well, to provide the needed solderable surface finish, as well as the wear protection needed, all on one circuit board. Available on PCBpro or Sunstone Custom Quote PCBs.
- Other — Sunstone Custom Quote offers additional surface finishes such as: Full body (hard) gold, soft bondable gold, O.S.P., lead-free solder, immersion tin and more.