Most first-spin failures are not exotic — they are the same handful of DFM misses, over and over. Run this checklist before you release, and you will catch the majority of them before a fab ever quotes the job.
Copper and spacing
- Trace width / spacing meets the fab minimum for your copper weight, not just your layout default.
- No acute slivers or acid traps at sharp copper intersections.
- No hanging copper — dangling traces and orphaned pours removed.
- Thermal reliefs on plane connections to keep pads solderable.
Drills and vias
- Annular ring verified against worst-case registration for your reliability class.
- Via-in-pad filled and capped where pitch demands it.
- Aspect ratio within the fab's plating capability.
- Drill sizes consolidated to a sane tool count.
Solder mask and legend
- Mask slivers between fine-pitch pads meet the minimum web width.
- Mask-defined vs copper-defined pads chosen deliberately.
- Silkscreen clipped off pads and clear of solderable areas.
Data package
- Netlist included, and it matches the copper.
- Stackup drawing with controlled-impedance targets called out.
- Fabrication notes specify finish, class, and material.
| Item | Common first-spin miss |
|---|---|
| Annular ring | Breakout at worst-case layer |
| Mask sliver | Bridging between BGA pads |
| Netlist | Missing or mismatched |
| Finish | HASL on fine-pitch part |
Engineering noteRun the check against your actual fabricator's rule deck, not a generic ruleset. A design that passes a generic DRC can still violate your specific plant's plating and etch limits.
None of this is glamorous, but the boards that come back working on the first spin are the ones where someone ran exactly this list before hitting release. When in doubt, get a DFM review before you commit tooling.
dfmchecklistmanufacturingfirst-spin