Plated Copper is simply Plated Through hole and Plated via Eletcroless Copper. Simply abbreviated as PTH, it is a self-catalyzed REDOX reaction.The process of PTH shall be carried out after the drilling of two or multiple layers of boards. The purpose of copper sinking is to add a layer of 0.3-0.5um copper in the holes based on the principle of chemical reaction, so as to make the previously non-conductive holes have electrical conductivity, so as to facilitate the smooth operation of plate plating and graphic plating behind, and thus complete the electrical intercommunication between PCB circuit board circuits.
PTH process decomposition: alkaline degreasing → second or third countercurrent rinsing → roughening (micro erosion) → second countercurrent rinsing → prepreg → activation → second countercurrent rinsing → gel → second countercurrent rinsing → copper sink → second countercurrent rinsing → acid leaching