Via-in-pad places an interconnect in a component land. It is a placement strategy and must be paired with a suitable filling and finishing process.
What to consider
An open hole beneath a soldered pad can change solder volume and joint shape. The fabricator and assembler should agree whether the via is copper filled or resin filled and capped, how flat the pad must be and what inspection is required. Tenting a hole is not equivalent to a qualified filled-and-capped pad.
A practical review example
For a fine-pitch BGA, compare a short dog-bone escape with a via-in-pad option. Include solder-mask registration, finished pad size and rework requirements in the decision.
Checks before release
- Specify filling, capping and finished surface requirements.
- Confirm the land matches the package assembly guidance.
- Review solder-joint inspection and rework feasibility.
Connect this decision to fabrication
Use the design checklist to organize the initial discussion. Keep proposed values separate from the approved drawing and document the effect of any change on the rest of the construction.
- Record depth and diameter using the same units and measurement convention.
- Check capture lands, target lands and registration together.
- Match the test coupon to the actual interconnect construction.
Technical references
Fabrication design guidelinesHistorical IPC microvia reliability warning (2019)References checked 2 October 2026. Manufacturer data describes its stated construction and is not an HDIPCB.org manufacturing commitment.