A Guide to ENIG (Electroless Nickel Immersion Gold) in PCBs
Printed Circuit Boards (PCBs) are the backbone of modern electronics, and ensuring their durability and performance often comes down to the type of surface finish applied. One of the most popular options in the electronics industry is ENIG — Electroless Nickel Immersion Gold. In this article, we’ll explore what ENIG is, how it works, and why it’s a preferred finishing process for high-performance PCBs. What is ENIG in PCB Manufacturing? ENIG is a two-layer metallic surface finish commonly applied to PCBs. It consists of: A nickel layer deposited through an electroless process, which acts as a barrier and provides mechanical strength. A thin layer of gold , applied via immersion, which protects the nickel and enhances solderability. This combination offers both durability and excellent electrical performance. The ENIG Process: Step by Step The ENIG finishing process follows a precise chemical sequence: Surface Preparation – The copper surface of the PC...