What is Anode

By Bester PCBA

Last Updated: 2023-08-14

Table of Contents

What is Anode

An anode is a positive electrode or terminal in an electrochemical cell or circuit component, which is important in various processes, such as electroplating and CAF (Conductive Anodic Filament) formation and failure.

In electroplating, the anode is responsible for supplying metal ions that are deposited onto the PCB surface. It serves as the source of the metal that will form a layer on the conductive surface during the electroplating process. The anode is typically made of a material that can be oxidized, such as copper or titanium, and it is immersed in an electrolyte solution containing metal ions.

In the specific context of CAF formation and failure, the anode refers to the location from which the conductive filaments grow towards the cathode. It provides an acid environment near conductors, enabling corrosion and the subsequent growth of conductive filaments. This growth can lead to electrical failure in the PCB.

The length and placement of anodes are important factors in achieving consistent copper thickness distribution during the plating process. Anodes should have a long service life and require minimal maintenance to ensure reliable and uniform plating results. They should also contribute to the stability and longevity of the plating bath, reducing the need for frequent maintenance and adjustments.