What is drowning in gold? Why Shen Jin?
1. What is drowning in gold?
To put it simply, immersion gold is to use a chemical deposition method to obtain a layer of metal coating on surface of a printed circuit board through a chemical redox reaction.
Second, why do you want to sink gold?
The copper on PCB is mainly red copper, and copper solder joints are easy to oxidize in air, which causes poor conductivity, that is, poor tin suction or poor contact, and reduces performance of PCB. .
Then it is necessary to carry out surface treatment of copper solder joints. Immersion gold consists in applying gold to it. Gold can effectively block copper metal and air to prevent oxidation. Therefore, immersion gold is a surface treatment method of anti-oxidation. The reaction coats copper surface with a layer of gold, also known as gold.
Third, what are benefits of surface treatment with immersion gold?
The advantage of immersion gold process is that color deposited on surface is very stable when circuit is printed, very good brightness, very smooth finish and very good solderability.
Immersion gold is usually 1-3 inches thick, so immersion gold surface treatment method is generally thicker, so immersion gold surface treatment method is usually used in keyboards, gold finger pads, etc. Circuit boards, because gold is highly conductive , good oxidation resistance and long service life.
Fourth, what are benefits of using immersed gold printed circuit boards?
Highlights are as follows:
1. The immersion gold plate is bright in color, good in color and luster and looks good.
2. The crystal structure formed by immersion gold is easier to weld than other surface treatments and can have better performance and quality assurance.
3. Since gold immersion board only has nickel-gold on pad, this will not affect signal because skin effect signal transmission occurs on copper layer.
4. The metallic properties of gold are relatively stable, crystal structure is denser, and oxidation reaction is not easy.
5. Since gold immersion board only has nickel-gold on pad, solder mask on circuit and copper layer are more strongly bonded, and a micro-short is not easily caused.
6. The project will not affect distance when compensated.
7. The voltage of immersion gold plate is easier to control.
Five, immersion gold and gold finger
The gold finger, to put it bluntly, is a brass contact, which can also be called a conductor.
In particular, since gold is highly resistant to oxidation and highly conductive, components connected to memory slot on memory card are plated with gold, and all signals are transmitted through gold fingers.
Because gold finger is made up of many yellow conductive contacts, its surface is plated with gold, and conductive contacts are arranged like fingers, hence name.
Generally speaking, gold finger is connector between memory card and memory slot, and all signals are transmitted through gold finger. The gold finger is made up of many gold conductive contacts. The gold finger is actually plated with a layer of gold on a copper clad laminate through a special process.
So, simple difference is that immersion gold is a PCB surface treatment process, while gold fingers are PCB components that have signal connections and conduction.
In real market conditions, gold fingers may not appear gold.
Due to high price of gold, most memory is currently being replaced by tinning. Since 1990s, tin materials have become popular. At present, almost all "gold fingers" of motherboards, memory and video cards used material, only some high-end server/workstation accessory contact points will continue to use gold-plated methods, and price is naturally high.
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