What is the PCB surface treatment process?

The surface treatment of Standard PCB includes: spray tin, lead-free spray tin, immersion gold, immersion tin, immersion silver, hard gold plating, full plate gold plating, gold finger, nickel palladium, OSP and other processes. Among them, immersion gold and gold plating are often used in PCB circuit boards. Some customers will hesitate in the surface development of new products. Is it better to use immersion gold or gold plating? What is the difference? How to choose? The PCB Industries Company will give you detailed answers below.

What we call the whole plate gold plating generally refers to "plated gold", "plated nickel gold plate", "electrolytic gold", "electric gold", and "electric nickel gold plate". There is a distinction between soft gold and hard gold. Generally, hard gold is Used for cheats.

The principle is to dissolve nickel and gold in chemical solution, immerse the circuit board in the plating tank and switch on the current to generate a nickel-gold coating on the copper foil surface of the circuit board.

Electro-nickel gold is widely used in electronic products due to its high hardness, wear resistance and resistance to oxidation.

Gold is produced by a chemical oxidation-reduction reaction method, which is generally thicker. It is one of the chemical nickel-gold gold layer deposition methods, which can achieve a thicker gold layer.

1. Generally, the thickness of immersion gold is much thicker than that of gold plating. The immersion gold will be golden yellow and yellower than gold plating, and customers on the surface will be more satisfied with immersion gold. The crystal structure formed by the two is different.

2. Because the crystal structure formed by immersion gold and gold plating is different, immersion gold is easier to weld than gold plating, which will not cause welding failure and cause customer complaints. At the same time, because immersion gold is softer than gold plating, gold finger circuit boards are generally gold-plated, and hard gold is wear-resistant.

3. The immersion gold board only has nickel-gold on the pads, and the signal transmission in the skin effect is that the copper layer will not affect the signal.

4. Compared with gold plating, immersion gold has a denser crystal structure and is less prone to oxidation.

5. As the wiring becomes denser and denser, the line width and spacing have reached 3-4 MIL. Gold plating is prone to short circuit of gold wire. The immersion gold plate only has nickel-gold on the pads, so it will not produce a gold wire short circuit.

6. The sinking gold circuit board has nickel-gold only on the pad, so the combination of solder mask and copper layer on the circuit is stronger. The project will not affect the spacing when making compensation.

7. Generally, it is used for relatively high-demand boards. The flatness is better. Generally, immersion gold is used. The immersion gold generally does not have a black pad phenomenon after assembly. The flatness and standby life of an immersion gold plate are as good as those of a gold plate.

8. Nowadays, gold is expensive on the market. In order to save costs, many manufacturers are no longer willing to produce gold-plated plates, and they only use immersion gold plates with nickel gold on the pads, which is indeed a lot cheaper.

Our company also has Aluminum PCB on sale, welcome to consult.