Foundry

A foundry, or fab, is the factory that physically manufactures integrated circuits. In the pure-play foundry model, the foundry owns no chip designs of its own; instead it fabricates wafers on behalf of fabless companies that design chips but operate no fabrication plant. This separation is the backbone of the modern semiconductor industry and of Bitcoin mining hardware specifically: none of the major mining ASIC vendors owns a fab.

The fabless-foundry split

ASIC vendors such as Bitmain, MicroBT, and Canaan design their hashing chips but rely on a foundry to build them. The leading-edge nodes used for competitive mining ASICs are produced by a small number of foundries, with TSMC being the dominant supplier and Samsung a secondary one. The S17 generation's BM1397 was a 7 nm part; the S19j Pro's BM1362 is fabricated on TSMC's 5 nm process; each subsequent generation has chased the newest node the vendor could secure. This concentration means access to foundry capacity is a strategic bottleneck: the company that locks in wafer allocation at the newest node can ship more efficient miners first, and in tight markets wafer supply — not demand — sets how many machines exist. For miners, that is worth internalising: the efficiency curve of the entire industry is gated by a handful of factories.

Inside a fab

A foundry runs hundreds of precisely controlled steps in cleanroom conditions — deposition, photolithography, etching, ion implantation, and chemical-mechanical polishing — repeated layer by layer to build transistors and the stacked metal interconnect above them. A single wafer can spend two to three months moving through the line. The enormous capital cost of a leading-edge fab, often tens of billions of dollars, is why so few companies operate at the frontier and why each new node's cost is amortised across every customer willing to pay for it, from smartphone SoCs to hashing chips.

From design handoff to hashboard

The interface between designer and foundry is tape-out: the moment the finalised layout is delivered and the mask set is manufactured. From there the foundry prints the design onto wafers, each carrying thousands of identical copies of the semiconductor die. After probe testing, dicing, and packaging, the parts are graded by chip binning — a practical reality every repair tech encounters, since chips from different bins can behave differently at the same voltage. Only then do they arrive at the miner assembler to be reflowed onto a hashboard.

Why decentralists should watch the fabs

Bitcoin's hashrate is globally distributed, but the silicon it runs on funnels through a remarkably centralised manufacturing chokepoint. That is not a protocol flaw — SHA-256 does not care which fab printed the chip — but it is a supply-chain concentration worth understanding. Open hardware efforts like the Bitaxe demonstrate the counterweight: the board design, firmware, and tooling can all be open even while the hashing chip itself comes from the same few foundries. Diversity in who can design, assemble, repair, and run miners is the layer of decentralization the community can actually build itself; understanding what happens inside the fab tells you where that work starts. Progress at the foundry frontier — from FinFET to GAAFET transistors — is what keeps Moore's law-style efficiency gains flowing into each new miner generation.

Foundries and the hardware cycle

The foundry cadence also sets the rhythm of the mining hardware market. A new node ramps over roughly two to three years: early wafers are expensive and yield-limited, so first-run machines carry premium prices; as yields mature, cost per chip falls and mid-cycle refreshes appear at better price-performance. Buying hardware with this cycle in mind — rather than chasing each launch — is one of the quiet edges available to smaller operators. It also explains why previous-generation machines remain rational purchases for heat-reuse and low-cost-power deployments: the fab already amortised its line on those wafers, the secondary market prices them accordingly, and a well-maintained board keeps hashing long after the foundry has moved two nodes ahead.

See who designs the chips in the manufacturers directory.