勛圖tv 繚 ENGINEERING GUIDE
Copper Filled Via: Electroplated Fill, Geometry and Evidence
A copper filled via contains deposited copper within the via cavity rather than only a hollow plated wall. It can support dense interconnection structures and alter electrical or thermal paths. It is distinct from resin fill, conductive paste and a thin copper cap over a nonconductive fill.
Define which copper structure is intended
Specify the hole geometry and layer span, whether the fill is required through the cavity, and any surface planarity or cap requirements. A photo of a filled microvia does not establish that a deep through hole can be filled by the same route. Geometry and process equipment influence the applicable filling method.
The filled-via material comparison explains alternative fill types. Use the present page when electrodeposited copper is central to the design, and the blind-hole panel-plating page when surface copper growth is the main process trade-off.
Filling and surface deposition happen together
During an electrolytic process, copper can grow inside the via and on other exposed conductive surfaces. The desired balance is not simply 'more copper everywhere.' Excess surface growth can make fine-line processing more difficult, while incomplete filling or undesirable surface shape can affect subsequent stages.
Atotech's published filling systems describe process-specific approaches to this balance. Their example geometries and performance belong to those systems and conditions. They are not evidence that 勛圖tv uses a particular chemistry or can guarantee every figure in a supplier brochure.
Model the cavity, not the production recipe
The worksheet treats the opening as a conical frustum using top diameter, bottom diameter, depth and count. A cylindrical hole is the equal-diameter special case. The output is an ideal volume useful for comparing design geometries. It does not estimate plating time, additive consumption or current distribution.
For an illustrative 0.10 mm deep cylinder of 0.10 mm diameter, volume is about 0.000785 cubic millimeters. A thousand such ideal cavities have about 0.785 cubic millimeters of internal volume. This excludes surface copper, roughness, process losses and any variation in the actual hole shape.
Electrical and thermal claims need the real geometry
Bulk copper in a cavity can create a different path from a hollow barrel. However, the full connection still includes lands, adjoining copper and interfaces. Do not infer a current rating or junction-temperature improvement from fill volume alone. Use representative material properties and system boundary conditions in the relevant analysis.
The via resistance worksheet is specifically a hollow-barrel DC model. It should not be applied unchanged to a solid filled structure. Selecting the correct model is part of the engineering review, not a cosmetic calculator setting.
Tapered microvia geometry
Tapered microvia geometry
Use the current inputs and keep the assumptions
Start with the example to understand the units and output, then use Clear for my inputs before entering your project. Example mode stays visibly labeled even if you edit its numbers. The form begins without a result so an illustrative value cannot be mistaken for an approved requirement. Every field must have a valid value; zero is accepted only where it has a meaningful role in the particular model.
Read the input notes before calculating. They identify the physical boundary and what is excluded. Keep the same unit convention across the drawing and worksheet. Changing an input invalidates the previous result and disables its download until you calculate again. This prevents an old number from appearing to describe a revised geometry.
The result is a screening record. A negative margin or an out-of-range condition identifies a question to resolve; a positive margin is not a manufacturing approval. Use the record with the actual drawing, material and project requirement. The model does not load CAD files, inspect images or retrieve private factory data.
Download the current result if it helps the discussion. The text includes the entered inputs, result and limitations. It stays on your device until you choose to attach or share it. Contact is a separate step; this page does not automatically populate the enquiry form or upload a file. Avoid confidential identifiers if you only need an exploratory calculation.
| Input | What to establish before using it |
|---|---|
| Review reference | Use a nonconfidential reference that lets you connect this calculation to the correct drawing revision. |
| Top opening diameter 繚 mm | Use the dimension at the entrance of the idealized cavity. This is not an equipment capability recommendation. |
| Bottom opening diameter 繚 mm | The model accepts a narrowing or cylindrical cavity with positive bottom diameter. Re-entrant and irregular shapes need another model. |
| Cavity depth 繚 mm | Use the local dielectric or cavity depth defined for the operation. Do not substitute total board thickness for a blind opening. |
| Number of equal cavities | Only equal ideal conical frustums are summed. Mixed geometries must be calculated separately; volume does not predict process time. |
Optional cost comparison from your own allowances
Use a quotation or a clearly labeled internal assumption for each input. Keep the quantity, construction and inspection scope the same when comparing alternatives. This uncalibrated planning model adds entered values; it contains no current market rates and does not issue a 勛圖tv quotation. You can contact the team without completing it.
Entered manufacturing cost scenario
Evidence to request
Agree how voids, seams, surface dimples or protrusion, and connection integrity are evaluated for the application. Identify the locations and construction represented by microsections. Where thermal reliability is important, discuss applicable testing and whether the sample matches the intended structure.
A visually attractive section is useful explanatory evidence but not a universal lot guarantee. Preserve its source and sample identity. Do not substitute an untraceable image for the agreed inspection and acceptance records.
Quotation and release details
Supply layer spans, actual cavity dimensions, hole count or subset, material stackup, surface requirements and any subsequent stacked stages. State whether copper filling is fixed or whether alternatives may be proposed. The optional budget worksheet accepts entered process and inspection allowances without creating a price from cavity volume.
Is conductive paste the same as electrodeposited copper? No. Does a copper cap prove the cavity is copper filled? No. Does filling eliminate every interface risk? No. Request a construction proposal that identifies the internal fill, outer surface and evidence needed for the product, then preserve it with the fabrication drawing.
Measure the right copper in the right location
Copper descriptions should identify both location and origin. Starting foil, a seed layer, electrolytic surface copper, barrel copper, fill and cap can coexist in one structure. A thickness value is only interpretable when the measurement location and included layers are stated. Do not compare a total-surface reading with a deposit-only requirement without reconciling those definitions.
Distinguish averages from local requirements. A panel can have an acceptable average while a critical location differs. The relevant inspection plan should identify hole families, panel positions and section locations that represent the construction. The appropriate sampling and acceptance criteria come from the agreed specification and project scope; a calculator cannot select them from a layer count.
The process route connects hole integrity with surface patterning. Copper needed for one interconnect operation may also appear on exposed surfaces and change the later etching task. Review fine-line geometry when the route changes. Conversely, reducing surface copper to simplify etching must not silently compromise a required barrel, cap or wrap condition. A cross-section and process map make these dependencies visible.
For filled structures, assess the internal and external results separately. A smooth surface does not prove a complete internal fill. A filled cavity does not establish every surrounding trace dimension. Ask which observations demonstrate void-related conditions, surface shape, connection continuity and final dimensions. Keep each result linked to the structure and location it actually represents.
Supplier chemistry and equipment documentation can explain a mechanism or a process option. It does not establish that a particular factory uses that system or has qualified the same performance. Treat brochure examples as examples with conditions, and ask for relevant manufacturing evidence when a design depends on a demanding feature. Do not turn a third-party product specification into an unverified 勛圖tv capability claim.
The quotation should identify the required construction, inspection and any separate qualification work. If alternatives are offered, compare their resulting copper geometry and acceptance scope before comparing price. Keep approved deviations with the release drawing. A well-defined plating review produces measurable copper requirements and an evidence plan, while leaving the qualified process controls with the responsible manufacturer.
Standards, source context and limits
Use the performance and acceptance documents named in the procurement agreement, including their revisions and any applicable addenda. A design guide explains choices; a product acceptance requirement defines what must be demonstrated. Neither a reference link nor a calculator result is a certification of the board or the supplier. Where a value is contractually important, check the controlled document and agree the measurement method with the responsible parties.
Examples on this page are deliberately labeled and are not advertised 勛圖tv limits. Supplier documentation is linked for the specific material or process context it explains. Equipment photographs and cross-section examples show the subject; they are not current production, inspection or qualification records for your order.