Resin Plugging & Via-in-Pad
Filled vias and via-in-pad structures for HDI, BGA breakout and better thermal paths.
PCB Technology & Capabilities
PRODUCTS CENTER
Get Custom Quote
PRODUCTS CENTER
Resin Plugging & Via-in-Pad (VIP/VIPPO)
Flat, void-controlled VIP delivers reliable micro-BGA assembly, shorter routes (VOP), better thermal paths, and cleaner high-speed signals.
Process Capability Matrix（Core Specs）
|
Technology |
Use Cases |
Min Via / Pad |
Max Lamination Cycles |
Max Layers |
Planarity (µm) |
Copper Cap (µm) |
Standards / Notes |
|
VIP (Copper-Capped) |
Micro-BGA, CSP, RF/5G |
Laser ≥0.050 mm / Pad ≥0.2 mm |
6–7 |
20–26 |
≤15–20 |
≤12 µm |
IPC-4761 Type VII, VOP-ready |
|
Resin-Plugged Through-Via |
Via transfer under BGA |
0.10–0.50 mm |
6–7 |
20–26 |
≤25 |
Optional re-copper |
Lower flux residue, higher SMT yield |
|
Copper-Filled Microvia |
Stacked / Skip |
0.075–0.10 mm |
6–7 |
14–20 |
≤10–15 |
Co-grows with surface Cu |
For stacked vias, stub reduction |
DFM & Package Rules（Designer-Ready）
|
Type |
Via Ø (mm) |
Pad Ø (mm) |
Fill Type |
Mask Strategy |
Typical Fan-out |
SMT Readiness |
|
Laser VIP (Microvia) |
0.075–0.10 |
0.25–0.32 |
Epoxy (NCF) |
Tent or micro-window |
0.40–0.50 mm BGA |
Planarity ≤10–15 µm |
|
Thru-Via Plug & Cap |
0.20–0.30 |
0.28–0.40 |
Epoxy (NCF/CF) |
Cover or windowed thermal |
Power/thermal pads |
Reduced ball collapse |
|
Stacked VIP (1-n) |
0.075–0.10 |
0.25–0.32 |
Epoxy (NCF) |
Align with upper VIP |
HDI build-up |
Recommend SM-tented |
|
Thermal VIP Array |
0.10–0.30 |
Via + 0.15–0.22 |
Epoxy（CF opt.） |
Windowed mask opt. |
Large thermal pads |
Enhanced heat path |
Manufacturing Flow & QC Checkpoints
Laser/Mech drilling → Desmear & plasma → Cu seed (PTH) → Pattern plating → Vacuum resin plug → Cure & planarization → Local copper-cap plating → Solder mask strategy → Finish (ENIG/ENEPIG/OSP) → X-ray / cross-section / white-light interferometry.
Assembly Collaboration（SMT-Ready）
Stencil: reduce aperture 5–10% for VOP pads; segment large thermal pads. Reflow: follow paste profile, ensure adequate soak on heavy-copper/thermal pads. Cleaning: low flux residue with plugged vias reduces ionic risk.
Typical Stack-ups & Use Cases
0.40 mm BGA: L1 VIP → L2 (VOP fan-down), TDR target ±5–8%, back-drill stub ≤ 0.20 mm. Thermal pads: 0.25–0.30 mm via array + CF plug + windowed mask tied to copper pour.
Common Defects → Countermeasures
Ball collapse/opens → tighter planarity, stencil reduction, reflow tuning. Solder beads/wicking → VIPPO mask cover, resin cure, window strategy. Large voids → vacuum plug recipe & cure pressure, grind planarity. Delam/cracks → stack-up CTE match, stop-flow design, cure curve. Impedance drift → copper roughness & dielectric control, back-drill.
Quality Standards & Verification
Standards: IPC-4761 Type VII, IPC-6012 Class 2/3, IPC-6018 (RF). Verification: X-ray (void ≤ 5%), cross-section, WLI planarity, TDR (±5–8%).
FAQs
Q: What’s the difference between VIP and VIPPO?
VIP is via-in-pad; VIPPO is VIP with solder-mask-over-pad for anti-wicking and better planarity.
Q: When to choose copper-filled microvia?
For stacked/skip structures to reduce stubs and improve reliability in dense HDI.
Q: Why is planarity critical?
≤15–20 µm reduces opens/bridges on fine-pitch BGAs and stabilizes paste transfer.
Get Custom Quote
PRODUCTS CENTER
World-class PCB & PCBA manufacturer focused on high-frequency and high-reliability boards for defense, aerospace, automotive and industrial electronics.
You can unsubscribe at any time with a single click.
Copyright © 2025 UltroNiu Electronics Group All Rights reserved.