Metal etchers are used for metal etching metal products with a permanent black or clear mark. Metal etch is a vacuum process where a reactive ion process and arc layer (anti reflective coating) are used to create metal pattern for interconnects on semiconductor devices. As the etcher gets closer to its PM a build up of polymer on the side walls of the chamber reaches a point where it cracks, showering the wafer below in large flakes, several microns in size. This results in the tool having to undergo a wet clean.