PCB Via Filling Process First, define the objective; then, select the materials
Preventing solder from entering the holes, achieving a smooth pad surface, and meeting specific thermoelectric requirements are distinct design objectives. Only by distinguishing between solder mask-filled holes, resin-filled holes, conductive-filled holes, and copper-filled microvias can clear manufacturing specifications be written.
To understand the process, start by clarifying these key points
Solder Mask Hole Filling
Use solder mask material to seal the holes. Unlike applying solder mask to the hole openings, this does not automatically ensure full-depth filling or a surface suitable for direct soldering.
Resin Filling of Holes
Use a specialized via-filling resin, and cure, level, and apply a copper layer as required. Suitable for structures that require control over via filling and surface finish; specific solutions must be confirmed.
Filling Holes with Conductive Material
Use fillers with conductive properties. Their thermoelectric performance depends on the material and manufacturing process and is not equivalent to that of solid copper; this page provides a comparison of manufacturing processes, and project feasibility must be evaluated separately.
Design Boundaries and Manufacturing Reviews
- Tenting
- This primarily covers the orifice; it does not mean the orifice is completely filled. Specify whether the treatment is single-sided or double-sided.
- Plugging
- Specify the materials, orientation, and filling requirements; the term itself does not guarantee that the hole will be completely filled.
- Copper Plating After Hole Filling
- It involves steps such as filling, flattening, and metal plating, unlike simply filling the holes.
- Copper Filling via Micro-Holes Electroplating
- Electroplated copper is used to fill the microporous structure, as opposed to filling with resin or conductive paste.
- Production Instructions
- Please specify the hole numbers, hole diameters, plate thickness, areas to be filled, and final surface finish requirements; avoid simply writing “Plug all holes.”
The manufacturing values cited are based on this site’s existing process capabilities. The listed limit values do not imply that all can be achieved simultaneously; the manufacturing plan will be finalized after the complete stack-up, hole layout, and materials have been confirmed.
View Full Manufacturing CapabilitiesBefore requesting a quote, prepare these three sets of documents
Production and Layer Files
Gerber or ODB++ files, drill files, stack-up diagrams, and layer-to-hole mapping tables; ensure that file versions are consistent.
Key Process Requirements
Specify the hole diameter, plating material, copper-clad area, surface treatment, and required tolerances.
Quantity and Inspection Requirements
Please provide the quantity for prototypes and production runs, the desired delivery date, inspection reports, and reliability verification requirements.
Frequently Asked Questions
Is a conductive plug the same as a copper plug?
No. Conductive paste plugging differs from electroplated copper plugging in terms of materials, processes, and results; orders should be placed using the actual process name.
Is it always possible to weld a hole in a plate after plugging it?
Not necessarily. For through-holes, you also need to verify that the surface is flat, the metal is fully covered, and the pads are properly finished; you cannot rely solely on the fact that the holes have been filled.
Submit the via design for engineering review
Shenzhen Jingpeng Electronics | We provide stack-up and via tables to help you assess manufacturability, cost implications, and delivery requirements.
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