In short
This glossary defines the terms used when running a silicon program, in plain language. It covers chip design milestones, verification and physical design, firmware and bring-up, equipment programs, and qualification and ramp.
Chip design milestones
- RTL freeze: the point after which the design's logic is no longer changed without a formal change order.
- Coverage closure: when verification has exercised the design to its agreed target.
- Timing closure: when the physical design meets its timing requirements.
- Tape-out: the release of the final design to the foundry for manufacture.
- Samples: the first chips returned from the fab, sent to the team and to customers.
- First-silicon success: the first chips working well enough to go to production without another tape-out.
- Re-spin: a second tape-out to correct a design that did not work the first time.
Design and verification
- RTL: register-transfer level, the code that describes a chip's logic.
- Design verification (DV): checking that the design does what the specification says.
- Regression: the full set of verification tests, run repeatedly as the design changes.
- Physical design (PD): turning the logic into a layout that can be manufactured.
- ECO: engineering change order, a change made after the design was meant to be stable.
- DFT: design for test, the structures added so the manufactured chip can be tested.
- IP: a pre-designed block, often licensed from a third-party vendor.
- PVT: process, voltage and temperature, the conditions a design must work across.
- Shuttle: a shared manufacturing run on which several designs are fabricated together.
- Mask set: the set of photomasks used to manufacture a chip, a major cost of each tape-out.
Firmware and bring-up
- Bring-up: getting first silicon running, with firmware, on the bench.
- Emulation: running the design on hardware before silicon exists, so software can start early.
- SDK: the software development kit a customer uses to build on the chip.
- Post-silicon validation: testing the manufactured chip against its specification.
Equipment and tool programs
- Alpha tool: the first internal build of a new equipment platform.
- Beta tool: a tool installed at a customer's fab for evaluation.
- Insertion window: the period in which a fab decides which tools it will use for a process node.
- Tool of record: the tool a fab has qualified and committed to for a process step.
- Long-lead part: a component with a long delivery time, often setting the schedule.
Qualification and ramp
- Qualification (qual): demonstrating that a product or process meets the customer's reliability and performance criteria.
- Reliability lot: a batch of parts put through stress testing as part of qualification.
- OSAT: outsourced semiconductor assembly and test, a company that packages and tests chips.
- Transfer: moving a product or process from one site or line to another.
- Ramp: increasing production volume after qualification.
- MES: manufacturing execution system, the factory's record of lots and operations.
Program terms
- Program: one deliverable with one end date and one accountable owner.
- Commitment: something promised, with an owner and a date.
- Baseline: the agreed plan against which changes are measured.
- Re-baseline: an approved change to the plan.
- Authority envelope: the actions an AI may take on a program without asking a person.
- Decision receipt: a signed record of one consequential action, with its reasoning and approver.