Several common high-frequency PCB board surface treatment methods
In high-frequency PCB proofing, different surface treatment methods are used according to the number of layers. Simple single-sided and double-sided. Usually, most of the surface treatment methods are tin spraying or OSP, and more than 4 layers. The frequency board adopts the surface treatment method of immersion gold more. Each PCB surface treatment method has its own characteristics. The following are several common high-frequency pcb prototype manufacturer surface treatment methods.
1. Spray tin
Tin spraying is also called hot air leveling (HASL). In the early days, it was the most commonly used surface treatment method for high-frequency PCB proofing. With the development of pcb, the tin spraying process has been very mature and the cost is low. Now there are lead-free tin spraying and lead spraying tin. Tin spraying is suitable for visual inspection and electrical measurement, and is one of the high-quality surface treatment methods in high-frequency pcb proofing.
2. Nickel gold
Nickel gold is also a relatively large PCB surface treatment method used in high-frequency PCB proofing. The nickel layer in nickel gold is a nickel-phosphorus alloy layer, which will not be described in detail here. Nickel gold is suitable for lead-free soldering, smt, switch contact design, aluminum wire binding, thick plates, etc. The surface is very flat and strong against environmental attacks.
3. Nickel palladium gold
Nickel-palladium-gold has been widely used in semiconductors. With the development, high-frequency pcb proofing is now gradually applicable. It is cheaper than ENIG and electro-nickel gold, suitable for a variety of surface treatment processes and stored on the board.
4. Electroplated nickel gold
Electroplated nickel gold has the difference between hard gold and soft gold. Hard gold is like gold-cobalt alloy, and soft metal is better than pure gold.
Nickel and gold electroplating on IC substrates (such as PBGA) is mostly used, mainly for bonding gold and copper wires; but when electroplating on the C substrate, additional conductive wires need to be made at the place where the gold fingers are bound. It can be electroplated only after coming out. In high frequency PCB proofing turnkey pcb assembly service, electroplated nickel gold is suitable for contact switch design and gold wire binding, suitable for electrical testing.