Before we point to the topic, I’d like to share one story with you first.
Recently, one of our customers, whose projects need ENIG(1u”) on whole surface, and we didn’t know these projects was strict with the gold surface on some special area.
There are two pre-treatment for ENIG, one is gridding plating, another is sand blasting. At first, what we used is gridding plate, so when customer watched the gold surface can saw some cracks.
To solve this issue, we suggested to try sand blasting ENIG pre-treatment. Compared with gridding plating, it only need slightly brush the plate. But it’s still cannot meet customer’s need.
For normal design, change the surface treatment from ENIG(1u”) to gold plating can completely solve this issue. But in this design, the PADs on boards are separate, and there are in different gridding with outside. So gold plating is infeasible for this design.
Only when the inner PADs lie in same gridding with big copper plate, the gold plating is feasible.
So, let going to today’s the topic. What’s the difference between ENIG and plating gold?
- The difference in process.
- ENIG is called immersion gold, achieved by chemical deposit. Through an oxidation-reduction chemical reaction, it formed a layer of coating. It’s one of chemical nickel-gold depositing methods, can reach thicker gold layer.
It need pre-treatment gridding plating and sand blasting before immersion gold, need brush the board to enhance the adhesion between the board and the gold surface.
2）Gold plating use the principle of electrolysis, also known as electroplating. Needn’t pre-treatment before plating gold.
- The difference in color.
ENIG is golden.
Plating gold will be slightly whiter (nickel color).
- The difference in performance.
The crystal structure between ENIG and gold plating is different. Compared with plating gold, ENIG is easier to weld and will not cause bad welding.
The stress of ENIG is more easily controlled, for the products with bond, more conducive to the processing of the bond.
Last but not least, as we mentioned at the beginning, if your project need plating gold, pls make sure these area need gold plating can connect with outside gridding.
Hope above information is helpful for you to know more about ENIG and plating gold.
If any further question, pls let us know.