The steps of the RF and DC magnetron sputtering process differ slightly, but will contain the following steps: A vacuum environment is created, containing the target material, the substrate and an inert gas. The gas becomes charged upon exposure to the current. The sputtering target materials will act as one node, while the substrate acts as the other. The gas flow ionises and collides with the surface of the target. Collisions caused in this process knock off metal ions into the plasma. The charged plasma particles then condense on the substrate surface, completing the thin film deposition. The charge distribution will vary whether you are using DC or RF techniques. The negatively-charged target material will remain as such in the DC process but alternate with the RF.