Surface Finish Comparison
The surface finish influences the cost, manufacturability, quality and reliability of your board. Compare the options Sunking offers below.
Surface finish application is one of the final steps in PCB manufacturing, designed to prevent oxidation of exposed copper and provide a solderable surface. Selecting the right finish is a critical material decision. If you're unsure which finish suits your project, contact us and we'll be happy to assist.
| Characteristics | HASL | HASL (LF) | ENIG | ENEPIG | HARD GOLD | SOFT GOLD | SILVER | OSP | WHITE TIN |
|---|---|---|---|---|---|---|---|---|---|
| Deposit | Dipped | Dipped | Immersion | Immersion | Electrolytic | Electrolytic | Immersion | Dipped | Immersion |
| Process Control | Poor | Poor | Fair | Fair | Fair | Fair | Fair | Poor/Fair | Fair |
| Process Cost | Low | Low | Medium | High | High | High | Medium | Low | Medium |
| SMT Pad Flatness | Dome | Dome | Flat | Flat | Flat | Flat | Flat | Flat | Flat |
| Thin Board Finish | No | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Thermal Cycle (times) | 2 | 3 | 2 | 2 | 2 | 2 | 2 | ~2 | 2 |
| Shelf Life | 1+ yr | 1+ yr | 1+ yr | 1+ yr | 1+ yr | 1+ yr | 9-12 mo* | 9-12 mo* | 9-12 mo* |
| Handling | Normal | Normal | Normal | Normal | Normal | Normal | Critical | Critical | Critical |
| Exposed Copper | No | No | No | No | Yes | No | No | Yes | No |
| RoHS Compliant | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Fine Pitch SMT | No | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| BGA & μBGA | No | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Flip Chip | No | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Wire Bonding | No | No | Yes (Al) | Yes | No | Yes (Au) | No | No | No |
| Contact / Connector | No | No | Yes | Yes | Yes | No | No | No | No |
| Reliability | High | Low/Med | High | High | Med/High | High | Med/High | Med/High | High |
| Solder Joint Integrity | Excellent | Good | Good | Good | Poor | Poor | Excellent | Good | Good |
| Thickness | 25–2000 μin | 25–2000 μin | 3–10 μin Au / 150–200 μin Ni | 1–2 μin Au / 8–15 μin Pd / 100–150 μin Ni | 30–50 μin Au (23K) / 100–150 μin Ni | 30–50 μin Au (24K) / 100–200 μin Ni | 6–18 μin | 8–24 μin | 25–60 μin |
μin = microinches. * Requires unique storage techniques. Data provided as typical values; consult us for project-specific guidance.
Not sure which finish to choose?
Our engineers will recommend the best finish for your application.