plated through and then filled with a conductive (or non-conductive) epoxy plugging ink. The ink is then planarized to create a flat surface before being plated over. Most commonly, this via will eventually be patterned into an SMT or BGA pad for soldering. Via-in-Pad conserves real estate and also provides a direct conduit for heat transfer. Current fine pitch BGA and flip-chip component footprints prohibit running traces and vias (typical BGA configuration). Instead, the BGA pad, trace, and via are combined into one single feature allowing for 50% space savings. Conductive inks (electrical and thermal) transfer heat from critical components. | Processes | Fabrication issues |
| 1. HDI via fill plating | 1. Voids / dimples |
| 2. Via plugging | 2. Surface planarity |
| 3. VIPPO / POFV | Click here for more |
Sample Boards
