ENEPIG Surface Finish

ENEPIG Surface Finish

Electroless Nickel / Electroless Palladium / Immersion Gold (ENEPIG) is an advanced and complicated surface finish. ENEPIG is similar to ENIG and was developed over a decade ago as a design improvement on the ENIG surface finish. ENEPIG recently became more popular due to a decrease in the price of palladium. The application process of ENEPIG is similar to the ENIG application process, with one extra step: the application of a palladium layer over the nickel layer, before adding the top gold layer. The palladium layer in the middle removes the possibility of “Black Pad”, caused by the nickel layer being corroded by the gold. The ENEPIG method forms a flat, coplanar, hard surface that is good for gold wire bonding, aluminum wire bonding, and provides excellent solder-ability.See below figure 1
Example of an ENEPIG Surface Finish

Pros

Flat surfaces
Strong
Lead-free
Good for PTH (Plated Through-holes)
Long Shelf Life

Cons

Expensive
Not Re-workable
Very Limited Availability
Complicated Process (Three Parts)

Back to the technology data.Please note that we at Hopetimepcb usually do not provide ENEPIG as one of our standard surface finish options. If a client is interested in this finish, we ask that they please contact one of our technical support specialists for further details about cost and lead time before finalizing their order.

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