Electroless Nickel Immersion Gold (ENIG)

ENIG is a two layer metallic coating of 0.05um-  0.10uM of Gold over 3uM to 8UM of electroless nickel. The Nickel is the barrier to the copper and is the surface to which the components are actually soldered to. The gold protects the nickel during storage and also provides the low contact resistance required for the thin gold deposits. ENIG is now arguably the most used finish in the PCB industry due the growth and implementation of the RoHs regulation.

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Printed Circuit Board with Electroless Nickel Immersion Gold (ENIG) Surface Finish

  • ADVANTAGES
  • Gold Wire-Bondable
  • Planar Surface
  • Consistent Thicknesses
  • Multiple Thermal Cycles
  • Long Shelf Life
  • Solders Easily
  • Good for Fine Pitch Product

 

DISADVANTAGES

X – Solder Joint Embrittlement

Potential When Incorrectly

Specified

X – Difficult to Control

X – Cannot be Reworked at PCB

Fabricator