Metal finishing Q&As since 1989

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Electroless Nickel Immersion Gold vs. Immersion White Tin

We currently use Immersion White Tin finish for our PCB's and it's been working out well. Several of our fab houses are asking us if we can move to Electroless Nickel Immersion Gold and away from Immersion White Tin because of processing cost associated with Immersion White Tin. Anyone have any problems with ENIG finish, or any reasons why we shouldn't consider this switch?

Joe Reina
Microwave Communications Systems mfg - Tampa, Florida, USA
2006

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Hello Joe,
Sorry it took so long to respond to your inquiry. About four years ago a shop I worked for asked me to generate three RFQ's for equipment and chemistry for EN and Immersion Au installation. When I reviewed the quotations with costs attached, I almost fell off my chair. The average cost was $11,600.00. We currently had three customers requesting the finish. Needless to say payback on the investment was years away. Electroless Ni chemistry is fairly user friendly, but immersion Au can be tricky. If your lab and plating personnel don't have the experience with either of the solutions, the learning process can be a nightmare. Both baths require close and careful attention to frequent analysis and accurate additions. If you had to go this route, it's a good idea to choose the same chemical supplier for the EN and Au to eliminate finger pointing when problems arise. You may want to ask the tech rep to stay with your people for a few days to get you kicked off. Hope this will be helpful to you.

Mark Baker
process engineer - Malone, New York
2006

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Sir,
Immersion tin is very easy to control, but immersion gold or electroless gold is very hard to control
there two types palladium base,nickel boron, both required good lab analysis, if something not in control you reject the whole production. even you can't strip the panels.


Thanks

Milind Patel
- Toronto, ON, Canada
2006