SURFACE FINISHES COMPARED
Lead-free HASL or EPIG: which PCB surface finish?
Lead-free HASL is the cheaper of the two, at $0.05–0.08 per square inch against $0.12–0.22 for EPIG. EPIG leaves a flat pad, which fine-pitch parts need; lead-free HASL does not.
- EPIG keeps longer before assembly: 12+ mo against 6–12 mo for lead-free HASL.
- Known risk with lead-free HASL: Flatness.
- Known risk with EPIG: Wire bond (EPIG).
Lead-free HASL and EPIG, as published
| Property | Lead-free HASL | EPIG |
|---|---|---|
| Cost, USD per square inch | 0.05–0.08 | 0.12–0.22 |
| Shelf life | 6–12 mo | 12+ mo |
| Reflow passes | 6+ | 5+ |
| Minimum pitch, mm | 0.5 | 0.3 |
| RF performance | Poor | Excellent |
| Gold wire bonding | No | EPAG only |
| Aluminium wire bonding | No | Limited |
| Standard | not published | Under dev. |
| Known risk | Flatness | Wire bond (EPIG) |
How this was counted
Both columns come from the surface finish table in the MPBxChange material catalogue, as its sources published them. Costs are indicative ranges in US dollars per square inch, not quotations, and move with the gold price and the fabricator. "Not published" means the source gave no value, not that the answer is no.