Editing Copper electroplating (section)

==Overview==
Copper electroplating takes place in an [[electrolytic cell]] using [[electrolysis]]. As with all plating processes, the part to be plated must be cleaned before depositing metal to remove soils, grease, oxides, and defects.<ref name="ASTM B322-99">{{citation | title = ASTM B322-99 Standard| url=https://www.astm.org/b0322-99.html}}</ref><ref name="Flott">{{cite journal |last1=Flott |first1=Leslie W. |title=Metal finishing: an overview |journal=Metal Finishing |date=January 1, 2000 |volume=98 |issue=1 |pages=20–34 |doi=10.1016/S0026-0576(00)80308-6 |url=https://doi.org/10.1016/S0026-0576(00)80308-6 |access-date=July 21, 2022 |language=en |issn=0026-0576|url-access=subscription }}</ref> After precleaning, the part is immersed in the cell's [[aqueous]] [[electrolyte]] solution and functions as the [[cathode]]. A copper [[anode]] is also immersed in the solution. During plating, a [[direct current|direct electric current]] is applied to the cell which causes the copper in the anode to dissolve into the electrolyte through [[oxidation]], losing [[electron]]s and [[ionization|ionizing]] into copper [[cation]]s. The copper cations form a [[coordination complex]] with salts present in the electrolyte, after which they are transported [[Electric current#Conventions|from the anode to the cathode]]. At the cathode, the copper ions are [[Reduction (chemistry)|reduced]] to metallic copper by gaining electrons. This causes a thin, solid, metallic copper film to deposit onto the surface of the part.

The anodes can be either simple copper slabs or titanium or steel baskets filled with copper nuggets or balls.<ref name="Barauskas" /> The anodes may be placed in anode bags, which are typically made of polypropylene or another fabric and are used to contain insoluble particles that flake off the anode and prevent them from contaminating the plating bath.<ref name="PFCu" /><ref>{{cite web |title=ANODE BAGS |url=https://www.anodeproducts.com/products/anode-bags/ |website=Anode Products Company, Inc. |access-date=July 23, 2022}}</ref>

Copper electroplating baths can be used to plate either a ''[[Electroplating#Strike|strike]]'' or ''flash'' coating, which is a thin highly-adherent initial layer that is plated with additional layers of metal and that serves to improve adhesion of the subsequent layers to the underlying substrate, or a thicker coating of copper that may serve as the finish layer or as a standalone coating.<ref name="Flott" />