The capability extract shows in thirty seconds what runs as standard and what carries a surcharge.
See capabilities →Send the files and an engineer reviews them against your build — free, before you enquire.
To the data check →The carrier that sits between a bare die and the main board. Structures finer than a standard HDI build, warpage held within a narrow window across the part, and a sequential build-up taken to its limit. This is the most demanding class we quote — it always starts with a feasibility review, and we publish no general limits for it.
An IC substrate does what a package does: it fans a die's I/O out from bond-pad pitch to something a board can route, and it does so in a few square millimetres. That means structures and microvias finer than a standard HDI build, and layer counts that would be unremarkable on a large board packed into a part the size of a fingernail. What is achievable depends on the design, so the values are confirmed per project rather than published here.
The dominant constraint is not the structure size but the flatness. A substrate that warps by more than a few tens of microns across its length will not accept a die reliably, and the warpage comes from the same asymmetry and copper-balance issues as any multilayer — only with far less tolerance. This is why the design conversation happens before layout rather than after data submission.
Structure sizes beyond the conventional etched HDI window. What is achievable is confirmed against your design in the feasibility review.
Microvia layers built up stage by stage, in a part measured in millimetres. The routing density is what makes the fan-out possible.
Flatness held tightly enough for reliable die attach — the parameter that most often decides whether a substrate design works.
| Parameter | Value | Note |
|---|---|---|
| Min. line / gap | on request | Confirmed per design in the feasibility review |
| Microvia Ø | on request | Laser-drilled; diameter confirmed per design |
| Build-up | sequential HDI | Number of build-up stages per design |
| Layer count | on request | Depends on die footprint and fan-out |
| Surface finish | ENEPIG | Bondable and solderable |
| Flatness | tightly toleranced | Confirmed per design in the feasibility review |
| Bump pitch | on request | Flip-chip attachment |
| Lead time | extended | Reflects the process complexity |
Guide values for pre-selection. Binding values are confirmed per project against your data.
The points below are what most often comes back as a query after data review. Settling them before layout freeze saves a loop.
Structure size, build-up and flatness interact in ways that cannot be resolved after routing. A feasibility review before layout freeze is not a formality here.
Warpage tolerance is a fraction of a normal board's. Copper distribution has to be balanced per layer and across the part, not just approximately symmetrical.
The bump or bond pad geometry drives the entire build-up. A change to the die pinout late in the project is a new substrate, not a revision.
The process has more steps, tighter inspection and lower yields than any other class. Schedule accordingly rather than treating it as a normal HDI order.
It is HDI taken past where normal HDI stops. The sequential build-up principle is shared, but the structure sizes and the flatness requirement are a different class — which is why the limits are confirmed per project.
Structure sizes against the process window, build-up against the routing requirement, copper balance against the warpage target, and the die attach method. It results in a build proposal you approve before layout freeze.
Substrates are panelised in large arrays, so volume helps a great deal. Prototype quantities are possible but the per-part cost is dominated by tooling and setup.
Partly. The tools are the same, but the design rules, the tolerance stack and the DFM checks are not. Send the intended rules with the enquiry so we can flag mismatches early.
Send us your data or a rough sketch. We check feasibility, name the cost drivers and answer within one working day.