plating, anodizing, & finishing Q&As since 1989
PWB: ENIG vs Gold over silver
August 14, 2012
Q. Our local PWB manufacturer is using a gold over silver process instead of the ENIG.
My understanding is they use sterling silver instead of nickel as barrier between the gold and the copper. But I could not find more on the net.
What are the pros and cons of gold over silver process?
Are there any risk of corrosion or delamination (MLB) of the PWB with this process?
- Auckland, New Zealand
A. Hi Jerome,
What I can think of is gold over silver instead of ENIG can avoid common ENIG defects such as black pad (black nickel), nickel skip plating, high temp and long plating time of electroless nickel causing soldermask blistering, etc. Also, ENIG is not good for gold wire bonding but gold over silver might be better.
However, running cost of gold over silver might be higher than gold over nickel.