PCB surface finishes protect exposed copper, enhance solderability, and influence overall assembly quality. Choosing the right finish depends on cost, reliability, component density, and long-term performance needs. This guide compares the most common options to help you make an informed decision.
Bare copper oxidizes quickly when exposed to air. Surface finishes prevent oxidation and improve wetting during soldering. Popular finishes ensure:
One of the most widely used finishes, HASL involves immersing the PCB in molten solder and removing excess with hot air knives.
Best for: General-purpose electronics, low-cost designs.
ENIG is one of the most popular premium finishes, providing a flat surface ideal for fine-pitch designs.
Best for: High-reliability electronics, medical devices, aerospace, fine-pitch components.
OSP uses an environmentally friendly organic coating to protect copper during storage and soldering.
Best for: High-volume consumer electronics with simple assembly.
A thin layer of silver deposited over copper provides strong conductivity and excellent solderability.
Best for: RF circuits, high-speed digital, controlled impedance applications.
Known as the "universal surface finish," ENEPIG includes a palladium layer between nickel and gold.
Best for: Medical, aerospace, high-reliability electronics.
| Finish | Cost | Planarity | Solderability | Reflow Durability | Best For |
|---|---|---|---|---|---|
| HASL | Low | Fair | Good | High | General, low-cost boards |
| ENIG | MediumâHigh | Excellent | Excellent | Excellent | HDI, BGAs, fine-pitch |
| OSP | Very Low | Excellent | Good | Poor | Simple consumer electronics |
| Immersion Silver | Medium | Excellent | Very Good | Medium | RF, impedance-controlled |
| ENEPIG | High | Excellent | Excellent | Excellent | High-reliability designs |
Consider the following when selecting a finish:
Xekera offers all major PCB finishes to support any application or budget. Our engineering team can help you choose the ideal finish based on your design requirements.