As is well known, the most commonly used copper foil on substrates is ED copper. Use various waste wires and cables to melt into Copper(II) sulfate plating solution. In a special large plating tank deep underground, the distance between cathode and anode is very short. Impulse the plating solution at a very high speed. With a high current density of 600 ASF, the columnar crystalline copper layer is plated on the smooth and passivated stainless steel barrel like drum. Because the adhesion of the passivated stainless steel drum to the copper layer is not good, Therefore, the plating surface can be torn off from the runner, and the continuous copper layer obtained can be made of copper foil with different thicknesses based on the speed and current density of the runner. The smooth copper foil surface adhered to the runner is called the Drum side, and the rough crystalline surface of the plating solution on the other side is called the Matte side. This type of copper foil: