There are different types of FPC circuit board production processes according to different requirements, and there are mainly 4 types.

The first type, immersion gold, also known as gold, is to chemically react between copper and gold on the surface of the substrate through a chemical method, and the other two are integrated together. Its advantage is that it can make the welding effect stronger, the color is bright and bright, and the disadvantages It is difficult to produce, because chemical reactions will occur during production, and related gases will be produced. Improper handling will produce toxic gases, which will cause certain damage to the production environment;

The second type is gilding. As the name implies, gold plating means spraying a layer of gold on the surface of the substrate. Because there is no chemical bonding of copper, the surface gold content is higher than that of sinking gold, and the gold is brighter, but the welding effect is not as good as that of sinking gold;

The third type is tin plating. Just like gold plating, tin is used instead of gold. The melting point of tin is not as high as that of gold, the hardness is not as high as that of gold, the color is poor, and the welding effect is better;

The fourth type, OSP, is the anti-oxidation process. It is also a chemical method, which can avoid or slow down the oxidation of the pad under a certain environment. It is the most used process in addition to gold in the FPC surface treatment process.