In the surface treatment of circuit boards, there is a very common process called immersion gold. The purpose of the immersion gold process is to deposit a nickel-gold coating with stable color, good brightness, smooth coating and good solderability on the surface of the printed circuit board.

In short, immersion gold is to use chemical deposition to produce a metal coating on the surface of the circuit board through chemical redox reactions.

1. The role of immersion gold process

        The copper on the circuit board is mainly red copper, and the copper solder joints are easily oxidized in the air, which will cause poor electrical conductivity, that is, poor tin eating or poor contact, which reduces the performance of the circuit board, so the copper solder joints need to be surface treated. , Immersion gold is plated with gold on it, gold can effectively block copper metal and air to prevent oxidation, so immersion gold is a treatment method for surface anti-oxidation, which is to cover the surface of copper with a layer of gold through chemical reaction, also known as chemical gold.

2. Immersion gold can improve the surface treatment of PCB boards

 The advantage of the immersion gold process is that the color deposited on the surface of the printed circuit is very stable, the brightness is good, the coating is very flat, and the solderability is very good. The thickness of immersion gold is generally 1-3 Uinch, so the thickness of the gold made by the surface treatment method of immersion gold is generally thicker, so the surface treatment method of immersion gold is widely used in circuit boards such as key boards and gold finger boards. Because gold has strong electrical conductivity, good oxidation resistance and long service life. 

3. Advantages of circuit boards using immersion gold boards

1) . The immersion gold plate is bright in color, good in color and good in appearance, which improves the attraction to customers.

2). The crystal structure formed by immersion gold is easier to weld than other surface treatments, and can have better performance and ensure quality.

3). Because the immersion gold board only has nickel gold on the pad, it will not affect the signal, because the signal transmission in the skin effect is in the copper layer.

4). The metal properties of gold are relatively stable, the crystal structure is more compact, and the oxidation reaction is not easy to occur.

5). Because the immersion gold board only has nickel-gold on the pad, the combination of the solder mask on the line and the copper layer is stronger, and it is not easy to cause micro-short circuit.