PCB manufacturers take you to understand the difference between immersion gold and gold-plated boards

Printed circuit boards we all know the difference between the color, but in fact does not have an impact on the performance, but today jiubao circuit editor want to take you to understand: the difference between immersion gold and gold-plated process. When the circuit board printed out, due to the different products we need to carry out a certain treatment of the surface of the circuit board to ensure the stability and quality of the circuit board. Generally speaking, the surface of the circuit board has several treatment processes: bare board (the surface does not do any processing), rosin board, OSP (organic solder protectant, slightly better than rosin), spray tin (leaded tin, lead-free tin), gold-plated boards, gold-plated boards, and so on, these are more common.

pcb manufacturer small reminder: all gold finger boards need to be gold plated or gold immersion.

Sinking gold using the chemical deposition method, through the chemical redox reaction method to generate a layer of plating, the general thickness is thicker, is a chemical nickel gold gold layer deposition method, you can achieve a thicker layer of gold.

Gold plating, on the other hand, uses the principle of electrolysis, also called electroplating. Most of the other metal surface treatment is also used in the electroplating method.

In the actual product application, 90% of the gold plate is immersed gold plate, because the poor weldability of the gold-plated plate is his fatal flaw, but also lead to many companies to give up the gold-plated process is the direct cause!

Sinking gold process in the printed circuit surface deposition of color stability, good brightness, flat plating, good solderability of nickel-gold plating. Can be basically divided into four stages: pre-treatment (degreasing, micro-etching, activation, after dipping), immersion nickel, immersion gold, post-treatment (waste gold washing, DI washing, drying). The thickness of gold immersion is between 0.025-0.1um.

Gold used in circuit board surface treatment, because of the strong conductivity of gold, good oxidation resistance, long life, general applications such as keypad, gold finger boards, etc., and gold-plated and gold-plated boards with the fundamental difference between the immersion of the board is that gold-plated is hard gold (wear-resistant), immersion of gold is soft gold (not wear-resistant).

1, immersion gold and gold plating formed by the crystal structure is not the same, immersion gold for the thickness of the gold is much thicker than gold plating, immersion gold will be golden yellow, more yellow than gold plating (this is one of the ways to distinguish between gold plating and immersion gold), gold plating will be slightly whitish (the color of nickel).

2, immersed gold and gold plating formed by the crystal structure is not the same, immersed gold relative to gold plating is easier to weld, will not cause bad welding. Immersion gold plate stress is easier to control, for products with bonding, more conducive to the processing of bonding. At the same time, it is also because of the immersed gold is softer than the gold plating, so the immersed gold plate to do the gold finger is not wear-resistant (the disadvantage of the immersed gold plate).

3, immersed gold plate only pads on the nickel gold, skin effect in the transmission of the signal is in the copper layer will not have an impact on the signal.

4, gold-immersed compared to gold-plated crystal structure is more dense, not easy to produce oxidation.

5, with the circuit board processing accuracy requirements are becoming more and more high, line width, spacing has reached below 0.1mm. Gold plating is prone to short-circuit gold wire. Immersion gold plate only pads on the nickel gold, so it is not easy to produce gold short circuit.

6, immersed gold plate only pads on the nickel gold, so the line of solder resistors and the combination of copper layer is more solid. Engineering in the compensation will not have an impact on the pitch.

7, for the higher requirements of the board, flatness requirements to be good, generally use immersed gold, immersed gold generally does not appear after the assembly of the black pad phenomenon. The flatness and service life of the immersion gold plate is better than the gold-plated plate.

So most factories currently use the immersion gold process to produce gold plates. In the PCB supplier editorial point of view, immersion gold process is more expensive than the cost of gold-plating process (higher gold content), so there are still a large number of low-priced products using gold-plating process (such as remote control boards, toy boards). So in the choice of surface treatment, you can go according to the cost of the product to consider, compromise choice.

Shenzhen jiubao technology Co., Ltd. production of PCB circuit boards has been more than 13 years, we are high-quality, good service, fast delivery to win the recognition of a wide range of customers, we will also be better technology and team to serve you as your strong shield, you can rest assured to engage in the production of the rest to us, such as you are interested in cooperating with us, please contact us at +86-755-29717836!