Federal funding built the fabs. It mostly didn’t fund the step that comes after. A wafer fabbed in the United States, then shipped overseas for dicing, packaging, and assembly, is not a domestic part — it is a domestic die in an offshore product.
Every reshoring conversation tends to treat “domestic semiconductor manufacturing” as though it ends at tape-out. For commercial silicon, that gap is mostly a cost story. For defense, aerospace, and programs with ITAR exposure or supply-chain traceability requirements, it is a structural gap that rarely appears in the program plan until it is too late to address cheaply.
Where the supply chain actually ends
A finished, tested, qualified part requires more than a domestic wafer. It requires domestic dicing, domestic packaging, domestic hermetic or RF assembly, and a traceable domestic inspection record. Each of those steps is a place where the chain can leave US soil — and for most programs, at least one of them does.
The facts that don’t come up in most reshoring discussions:
- Hermetic and high-reliability packaging capacity. Domestic capability for hermetic, RF, and high-reliability assembly is concentrated in a small number of shops. This is not a perception gap — it is a capacity gap.
- Prototype-volume invisibility. Builds of 10 to 10,000 units fall through the cracks between large offshore OSATs and academic or hobbyist setups. Most defense and industrial programs live in that band for 12 to 24 months.
- Process knowledge transfer lag. Equipment moves faster than the process knowledge to run it. Domestic capacity that exists on paper takes years to produce qualified, traceable output.
- Traceability chain continuity. Most defense programs require end-to-end supply chain documentation. A packaging step that touches an offshore OSAT breaks that chain even if every other step was domestic.
- Planning-versus-audit timing. Programs that discover a packaging dependency at a supply chain audit face a different problem than programs that identified it at planning — and the difference is measured in schedule and cost.
The gap the funding missed
The CHIPS Act and the programs that followed it were designed around wafer fabrication. Packaging — the step that turns a wafer into a part a system can use — received a fraction of the attention and a fraction of the capital. The result is a domestic fab infrastructure that produces advanced silicon and then hands it to an offshore OSAT to finish. That is not a complete domestic supply chain. It is domestic front-end with an offshore back-end.
For programs where “domestic” is a contractual or regulatory requirement, the distinction is not academic. A part that left US soil for packaging does not satisfy a domestic-content clause, regardless of where the wafer was grown or the mask was written.
What planning early looks like
The programs that get this right treat packaging as a supply-chain decision made at program planning, not a detail resolved at first article. That means identifying the packaging steps, mapping them against domestic capacity, and qualifying a domestic supplier before the schedule requires it. The programs that get it wrong discover the gap when the part is already designed, the build date is already set, and the substitution is a schedule impact.
US-soil packaging and hermetic assembly for programs that need traceable, end-to-end domestic execution is the work we do at Heisler Semiconductor. If your supply chain plan has the fab covered and the packaging step is still an open question, that conversation is easier to have now than after the first article date is on a contract.