For metal substrate, copper and aluminum are used in PCB, but have various applications;
However, if we discuss it from the Angle of the PCB Plating, we get a totally different answer:
PCB plating mainly includes copper, tin, nickel and gold plating.Copper plating is an important processing technology in PCB manufacturing.
As you know, copper plating has the advantages of good electrical conductivity, thermal conductivity, mechanical malleability and so on, namely, copper immersion after drilling, electroplating of the whole PCB, and thickening circuit with copper, all of which are to ensure electrical conductivity;In addition, ordinary plating solution is CuSO4;
In short, the process goes like this: drilling – immersion copper-plating – wire-drawing – etching