Roles of Agitator / Cathode Rocker

Agitator is a device for swinging an item. The purposes of use when plating are as follows;

1. Improve the separation of hydrogen gas generated from the cathode
2. Thin or stabilize the diffusion layer on the cathode surface
3. Supply ions to the plating reaction surface.

If hydrogen gas stays on the surface of the cathode, it will hinder precipitation and cause pit (dents). In addition, stabilizing the diffusion layer and efficiently supplying the ions in the bath to the cathode is very
important for the uniformity of the film and the smoothing of the surface.
There are various rocking methods such as those that move the object to be plated and those that move the rod (paddle), and there are various swing directions such as vertical and horizontal, which are used
according to the purpose.

Rocking direction

Rocking directions are 3 types; vertical (up/down), horizontal (left/right), and 3D (up/down, left/right, front/back).

Rocking Type

There are two types of rocking. Please see this video for the difference between impact type and smooth type motion.

Comparison Table – Agitator