As the integration level of ICs increases, the number of IC pins also increases. However, the vertical tin spraying process is difficult to blow flat the fine solder pads, which brings difficulty to SMT mounting; In addition, the shelf life of tin spray boards is very short. And the gold-plated plate precisely solves these problems:

1. For surface mount technology, especially for 0603 and 0402 ultra small surface mount, the flatness of the solder pads directly affects the quality of the solder paste printing process and has a decisive impact on the quality of subsequent reflow soldering. Therefore, whole board gold plating is often seen in high-density and ultra small surface mount processes. In the trial production stage, the influence of factors such as component procurement is often not that the board is soldered immediately upon arrival, but that it often has to wait for several weeks or even months before use. The shelf life of gold-plated boards is longer than that of lead-tin composite boards

Gold is many times longer, so everyone is willing to use it. Moreover, the cost of gold-plated PCBs in the sampling stage is almost the same as that of lead tin alloy plates.

But as the wiring becomes denser, the line width and spacing have reached 3-4 MIL. Therefore, it has brought about the problem of gold wire short circuit

As the frequency of the signal increases, the impact of the skin effect on signal transmission in multiple coatings becomes more pronounced on signal quality

Skin effect refers to the phenomenon where high-frequency alternating current tends to concentrate on the surface of a wire.

1. Generally, sinking gold has a much thicker thickness than plating gold, and sinking gold will appear golden yellow, which is even more yellow than plating gold. Customers are more satisfied with the surface of sinking gold. The crystal structures formed by these two are different.

2. Due to the different crystal structures formed by sinking gold and plating gold, sinking gold is easier to weld than plating gold, which will not cause poor welding and cause customer complaints. At the same time, precisely because sinking gold is softer than plating gold, gold finger boards are generally chosen to be plated with gold, which is hard and wear-resistant.

3. The sinking gold plate only has nickel gold on the solder pad, and the signal transmission in the skin effect is in the copper layer without affecting the signal.

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

5. As the wiring becomes denser, the line width and spacing have reached 3-4 MIL. Plating gold can easily cause short circuits in the gold wire. The sinking gold plate only has nickel gold on the solder pad, so it will not produce gold wire short circuits.

6. The sinking gold plate only has nickel gold on the solder pad, so the bonding between the solder mask on the circuit and the copper layer is stronger. The engineering compensation will not affect the spacing.

7. Generally used for boards with relatively high requirements, with good flatness, sinking gold is generally used, and sinking gold generally does not cause black pad phenomenon after assembly. The flatness and service life of the gold-plated plate are as good as those of the gold-plated plate.