This analysis is part of our PCB Visualizer set of tools and the results are available in the DFM section of PCB Checker. For every board we calculate a plating index, and show a graphical image that highlights areas on the board that risk to be underplated or overplated during the galvanisation process. The aim is to achieve a plating index as close as possible to 1, the score for a perfectly balanced copper distribution.
To start the galvanisation, we first fix the production panels to fly-bars. A set of maximum 4 panels run together on a fly-bar through the galvanic line. This fly-bar creates an electrical connection to the power supply. The production panels act as cathodes in the process. The production panels travel through different tanks, each with a different function, such as cleaner, micro-etch, copper and tin galvanisation, rinsing and drying.
Copper is electroplated onto the surface of the exposed copper of the production panel. We can deposit copper in the holes as well, thanks to the conductive carbon layer we built into the holes before the imaging process.
For copper galvanisation we can use two different power supplies:
Direct current, called DC
Pulse plating, called PP
These two methods have a different influence on the distribution of the copper over the panel. Let us look at it more in detail now.