The 2.5D/3D Package brings dies that would otherwise sit apart on a board into a single structure: chiplets, digital logic, power modules and RF system-in-package blocks are placed side by side or stacked, interconnected, and sealed as one device. For a design team chasing miniaturisation, this is the point where functional convergence stops being a board-layout problem and becomes a packaging decision.
Two configurations sit under one platform. In a 2.5D layout the dies are carried side by side on a common interconnect platform, so each one keeps its own known-good position while the paths between them get shorter. In a 3D layout the dies are stacked, interconnect density rises again and the footprint stops growing with every function added. Choosing between them is a heterogeneous integration question: it depends on how many functions have to coexist, how much heat they produce, and how short the path between them has to be.
Chipset designers and embedded system manufacturers come to this package when a design has run out of board area, when several dies must behave as one device, or when a module has to shed the latency between its RF front end and its digital section. Both configurations run through the same SiP package platform, so a later move from side by side to stacked does not mean changing partners mid-programme.
The finished part is a flat, low-profile module — a metal lid over the assembled dies, with the board edge and its connector strip left exposed for board-level mating.
| Package family | 2.5D/3D package, side-by-side and stacked configurations |
| Die types | Chiplets, digital logic, power modules, RF system-in-package modules |
| Integration | Multi-die assembly in a single structure |
| Interconnect | High-density interconnect with optimised signal paths |
| Thermal design | Dissipation planned across adjacent and stacked dies |
| Isolation | Separate return paths, with electrical isolation between die groups |
| Customisation | Stack, layout and compliance requirements tailored to the design |
| Simulation | Package and thermal modelling before tooling is committed |
| Build | Manufactured in our own advanced packaging facility |
| Verification | Electrical test, reliability assessment, failure analysis |
| Production | Prototype builds through to volume production |
Heat has further to travel and less room to spread. In a stacked structure the thermal path is planned while the package is still a model: which die sits closest to the lid, where the power blocks go, and how much metal area each function gets. The target is that every die stays inside its own operating window at the load the application actually applies, not at a bench condition.
Short paths, controlled parasitics. Dies that talk to each other at speed are placed close together, and the interconnect between them is kept short so inductance and capacitance stay where the model says they should. Parasitic effects are designed rather than absorbed later, because a stacked body leaves very little room to correct a poor path once the build is done.
Keeping functions apart. RF, power and digital blocks behave badly when they share an unplanned ground or sit too close together. The layout separates them, gives each its own return path, and adds electrical isolation between die groups where the design calls for it — which is what allows an RF front end and a digital section to live in one enclosure without the digital noise arriving at the receiver.
As an advanced semiconductor packaging manufacturer, we treat the thermal and electrical model as a deliverable in its own right: it is reviewed with your engineers before tooling, so the first build starts from predicted numbers instead of trial parts.
Most SiP semiconductor programmes have one function that dominates the design — the hottest die, the fastest interface, or the tightest isolation requirement. Once that is identified the rest of the stack is arranged around it, which is why two projects with similar die counts can end up with quite different structures.
Compliance designed in from the start. The compliance and safety requirements a programme has to meet are carried into the layout, the material set and the inspection plan, so they shape the build instead of being checked against it at the end.
Documents issued for the project. Certificates, test reports and material declarations are prepared around the specific programme. Tell us at the start of an advanced semiconductor packaging project what your quality team needs to see and we will confirm what can be provided — the paperwork is agreed alongside the technical scope, not after the first shipment.
Records that follow the lot. Build records travel with the lot through the process, so a question raised months into production can be answered from the record rather than reconstructed from memory.
The same standard on every run. Consistency between the first build and the tenth matters as much as the first result: the same procedures, the same inspection points and the same acceptance criteria apply each time a wafer set goes through.
One set of records. Design simulation, manufacturing, test and analysis sit inside our own facility, so the inspection results, the paperwork and the answers all come from the same team. When your quality department asks why a lot behaved the way it did, there is one party to ask — which is what most teams are really looking for when they shortlist a chip packaging service provider.
Package selection is rarely a catalogue decision. Our engineers review your die, interconnect and thermal requirements together with your design team before anything is built, and recommend the package format and lead count that suit your board, your test plan and your production volume. Because design simulation, manufacturing and reliability testing sit within the same team, feasibility questions and qualification findings come back with a clear answer. Drawing on more than 30 years of shared packaging expertise, we also help trace yield and reliability problems back to their root cause.
Chiplets, digital logic, power modules and RF system-in-package blocks are the four families we build with most often, and they can be mixed in one structure — logic beside memory, power conversion beside the die it feeds, an RF front end alongside its digital control. The limit is set by the design rather than by a fixed list: we review the die set, the interconnects each one needs and the isolation each one requires, then propose a stack that fits. Hybrid multi-chip configurations are the normal case rather than the exception.
Three signals usually point that way: board area has run out, the path between two dies has become the performance limit, or several functions have to ship as one qualified device rather than as a set of separately packaged parts. If a single die in a substrate package still meets the thermal and signal budget, that route is simpler to build and to qualify. We look at the die list, the power map and the end application together before recommending a stack, because 2.5D/3D only earns its place when the density or the path length actually buys something.
Yes. The stack, the interconnect scheme and the isolation between die groups are designed around your layout and your performance targets, and the compliance requirements your programme has to meet are built in from the start rather than added afterwards. Our simulation and manufacturing teams work from your design files, so the discussion starts with your die list and footprint. That is the practical difference between working with a chip packaging service provider on a custom build and picking a catalogue part number.
Both are planned while the package is still a model. Heat is routed deliberately — which die sits closest to the lid, where the power blocks go, how much metal each function gets — and signal paths are kept short so inductance and capacitance do not erode performance at frequency. RF, power and digital functions get their own return paths and electrical isolation where needed, so one does not corrupt another inside the same enclosure. The result is a SiP semiconductor module that holds its numbers at the load and the frequency the application actually uses.
Electrical test confirms the module behaves as designed, reliability assessment then examines how it holds up over time and under stress, and failure analysis traces any deviation back to its process step or design assumption. Because test, reliability and analysis sit on one platform in our own facility, findings come back with a cause attached rather than as a bare pass or fail. As a semiconductor packaging manufacturer we agree the documentation set with your quality team at the start, so the reports needed for internal qualification are planned rather than requested late.
That is the point of building both on one platform. The process controls used for the first SiP system in package build are the ones that hold in production, so the design characterised on the bench is the one that ships. Where a programme spans several die revisions, we keep the package definition and the simulation model current, so each revision is compared against the same baseline instead of being re-invented.
