Printed Circuit Board - PCB

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PCB finishes refer to the surface treatment applied to the printed circuit board (PCB) after the etching process to protect it from environmental factors and enhance its electrical performance. Some common PCB finishes include:

• HASL (Hot Air Solder Leveling) - a tin-lead alloy is melted and leveled over the surface of the PCB to provide a smooth, flat surface for component mounting.

• ENIG (Electroless Nickel Immersion Gold) - a layer of nickel is deposited on the surface of the PCB followed by a thin layer of gold. This finish provides excellent solderability and good resistance to oxidation and corrosion.

• OSP (Organic Solderability Preservative) - a thin organic coating is applied to the surface of the PCB to protect it from oxidation. This is a cost-effective alternative to ENIG but has a shorter lifespan.

• Immersion Silver - a layer of silver is deposited on the surface of the PCB to provide good solderability and resistance to corrosion.

• Immersion Tin - a layer of tin is deposited on the surface of the PCB to provide good solderability and resistance to corrosion.

The choice of PCB finish depends on the specific requirements of the project, such as environmental factors, cost, and electrical performance.