To protect the copper solder pads on a PCB from oxidation, contamination and to enhance their solderability, they need to be protected with a Surface Finish and these must conform to the European Union RoHS & RoHS2 (Restriction of Hazardous Substances) Directives.
But which is the right Surface Finish for your PCB’s?
In accordance to this directive Eurocircuits offers the following Lead-free Surface Finishes:
- Hot Air Levelling or Hot Air Surface Levelling (HAL or HASL).
- Chemical Ni/Au (Electroless Nickle/Gold – ENIG).
- Chemical Ag (Immersion Silver).
- Electroplated Ni/Au (Hard Gold) for Edge Connectors.
-
Carbon (Chemical C) for Switch Contacts.
Each has its own advantages and disadvantages and the goal is to select the one that best fits you the Function and Usage of the PCB.
For more information please read our post Selecting the Right Surface Finish for your Design.
Another important point about Lead-free soldering this that it requires higher soldering temperatures which have a direct effect on the reliability and durability of your PCB.
For more information please read our post on How Often Can You Raise a Eurocircuits PCB to Lead-free Soldering Temperatures.
The Eurocircuits Team.
