Immersion gold process

Immersion gold process is a surface finishing method used in the electronics industry to deposit a layer of gold onto the surface of printed circuit boards (PCBs). The immersion gold process is also referred to as electroless nickel immersion gold (ENIG) or chemical immersion gold (CIG).

The immersion gold process involves several steps:

Surface preparation: The surface of the PCB is cleaned and activated to ensure good adhesion of the gold layer.

Electroless nickel deposition: A layer of nickel is deposited onto the PCB using a chemical process that does not require electricity.

Immersion gold deposition: A layer of gold is deposited onto the nickel layer by immersing the PCB in a gold-containing solution.

Gold thickness measurement: The thickness of the gold layer is measured to ensure it meets the required specifications.

Post-treatment: The PCB is rinsed and dried to remove any residual chemicals and ensure the surface is clean and free of contamination.

The immersion gold process is preferred over other surface finishing methods because it provides a reliable, uniform, and corrosion-resistant layer of gold that is suitable for wire bonding and other electronic applications.