1. Chemical copper plating

It is on a surface with catalytic activity that copper ions are reduced and precipitated through the action of reducing agents:

Reduction (cathodic) reaction: CuL2++2e - → Cu+L

Oxidation (anodic) reaction: R → O+2e-

Therefore, the main reaction formula for using sodium hypophosphite as a reducing agent for electroless copper plating is: 2H2PO2-+Cu2++2OH - → Cu+2H2PO3+H2 ↑

In addition to being thermodynamically valid, chemical reactions must also satisfy kinetic conditions. Chemical copper plating, like other catalytic reactions, requires thermal energy to allow the reaction to proceed, which is why the plating rate only occurs when the chemical plating solution reaches a certain temperature. In theory, the rate of electroless copper plating can be expressed by the rate at which the concentration of reaction products increases and the concentration of reactants decreases. Due to the presence of certain additives in the actual chemical copper plating solution, its influence factors become too numerous and the situation becomes too complex. Therefore, most studies on the kinetics of chemical copper plating reactions start with the most basic components in the plating solution.

2. Electroplated copper

The specific process is as follows: The smooth progress of the electroplating process requires the following conditions: electroplating power supply (which can convert alternating current into direct current), plating solution (which contains coated metal, how to electroplate copper, the plating solution must contain copper ions, and so on, in addition to copper ions, the plating solution also contains other ions), workpiece (in electroplating, the workpiece must be conductive, otherwise electroplating cannot be carried out) Polar plate (there must be two levels during the electroplating process, with the workpiece serving as the cathode and the anode made of inert materials or coated metal plates); With the above items for assembly, you can turn on the power to electroplate and the coating can be formed.