Via Fill Epoxy
CAS Number: 25068-38-6
Via fill epoxy is a specialized thermosetting epoxy paste used to plug through-holes and blind vias in PCBs to create a planar surface suitable for component mounting and fine-pitch interconnection. It eliminates via-in-pad solder wicking problems and enables higher routing density in HDI designs. Formulated with controlled CTE and low void content for reliable thermal cycling performance.
Technical Specifications
| Tg | 130–160°C |
| CTE | 25–40 ppm/°C |
| viscosity | 200,000–600,000 cP |
| appearance | Black or green paste |
| voidContent | <3% after cure |
| cureCondition | 150°C / 60 min |
Applications
- HDI PCB via-in-pad plugging
- Blind via filling for build-up layers
- Through-hole plugging for surface planarization
- High-frequency PCB via sealing
- Military and aerospace HDI board fabrication
Key Features
- Eliminates via-in-pad solder wicking defects
- Low void content for thermal cycle reliability
- Planar surface after cure and planarization
- Compatible with ENIG and HASL surface finishes