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Course contents

  • How to Use This Course
  • PD Flow Overview — RTL to GDSII
  • Data & Libraries — What PD Receives
  • Data and Libraries49
  • Floorplanning Expanded65
  • Power Planning57
  • Placement65
  • Clock Tree Synthesis57
  • Routing65
  • Timing Closure81
  • Signal Integrity and Variation41
  • Power Signoff57
  • Physical Verification65
  • Physical Design Integration49
  • Signoff and Tapeout49
    • Closure Metrics Dashboard
    • Tapeout Checklist Engineering
    • Handoff to Foundry Operations
      • Handoff to Foundry Operations — Mechanism
      • Handoff to Foundry Operations — Inputs & Outputs
      • Handoff to Foundry Operations — Reports & Metrics
      • Handoff to Foundry Operations — Debug Playbook
      • Handoff to Foundry Operations — Worked Example
      • Handoff to Foundry Operations — Pitfalls & Red Flags
      • Handoff to Foundry Operations — Interview Drills
      • Handoff to Foundry Operations — Review Checklist
    • Post-Mask ECO Decision Flow
    • Revision Tagging and Reproducibility
    • Risk Review and Executive Signoff
    • Signoff and Tapeout Tricky Q&A
  • PD Interview Prep5
  • PD Closure Cheat Sheet
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‹Handoff to Foundry Operations
  1. Topics
  2. Physical Design
  3. Signoff and Tapeout
  4. Handoff to Foundry Operations
  5. Handoff to Foundry Operations — Inputs & Outputs

Physical Design · All levels

Handoff to Foundry Operations — Inputs & Outputs

Inputs & Outputs for Handoff to Foundry Operations (Signoff and Tapeout).

On this page

    Inputs required

    • Final layout export

    • Deck/version manifest

    • Waiver packet

    • Package interface data

    Outputs produced

    • Foundry handoff package

    • Intake checklist acknowledgement

    • Submission audit record

    Handoff owners

    • PD owner

    • CAD/methodology

    • Timing lead for constraint review

    Production handoff contract

    Treat Handoff to Foundry Operations inputs as a signed contract between RTL, synthesis, CAD, IP, package, timing, and PD. A 10+ year engineer blocks execution when the contract is ambiguous instead of burning runtime on invalid databases.

    Diagram
    HANDOFF MANIFEST
      design_tag: <rtl/netlist/def tag>
      constraints_tag: <sdc/upf/mmmc tag>
      library_stack: <pdk/lib/lef/tech/qrc tag>
      signoff_corner_set: <corner/mode list>
      owner_of_truth: <team/person>
      known_risks: <open waivers or assumptions>

    Senior acceptance rules

    1. Reject mismatched views before optimization starts.

    2. Record the owner for every assumption that is not locally provable.

    3. Preserve enough metadata that another engineer can reproduce the run in six months.

    Deep dive: how this shows up in real closure

    Tapeout is an auditable decision backed by tagged artifacts.

    Reports and artifacts to inspect

    • closure dashboard: timing, power, PV, DFT, package, and open waivers

    • revision manifest: RTL, netlist, SDC, GDS/OASIS, library, rule deck

    • waiver register: rule, count, owner, approver, expiration

    • foundry handoff package checklist

    Mini case study

    Timing and power are green, but the GDS tag differs from the STA database tag. The design is not ready. Reconcile the manifest and rerun signoff on the exact export database.

    Debug branches

    • If a metric is yellow, name the owner, date, and mitigation before signoff review.

    • If the tag is mismatched, stop export; traceability is a hard gate.

    • If post-mask ECO is requested, confirm allowed metal layers before promising a fix.

    Senior review question

    Ask yourself: what single report line would prove this page's concept is either passing or failing?

    What changes at 10+ years

    • You are expected to predict what your fix can break before running it.

    • You should recognize when the issue is methodology, not one block's implementation.

    • You should communicate risk in tapeout language: owner, evidence, impact, mitigation, and decision date.

    Principal-level review bar

    Deep subpage pages in this course should be read like real closure review material. For a 10+ year PD engineer, the bar is not remembering terminology; it is making a release-quality decision under ambiguity.

    What excellent looks like

    • Names the failing metric, corner/mode, database tag, and analysis switches before proposing a fix.

    • Separates data, constraint, physical, tool, and methodology root causes instead of treating all failures as optimization problems.

    • Chooses experiments by information gain and reversibility, not by habit.

    • States regression blast radius across timing, route, power, PV, DFT, package, and tapeout manifest.

    • Turns recurring failures into methodology guardrails, dashboards, or checklist items.

    Closure note template

    Diagram
    STAFF / PRINCIPAL CLOSURE NOTE
    
    Context:
      stage: <pre-CTS | post-CTS | post-route | post-fill | signoff>
      tag: <database / netlist / SDC / library stack>
      failing metric: <exact report line>
      affected scope: <block / hierarchy / path group / power domain / region>
    
    Hypotheses:
      H1: <most likely physical or constraint mechanism>
      H2: <competing explanation>
      H3: <methodology or input-data issue>
    
    Decision:
      next experiment: <cheap check that can falsify H1>
      fix candidate: <minimal reversible change>
      rollback trigger: <metric that says the fix is wrong>
      regression set: <timing / route / power / PV / DFT / package>
      escalation owner: <team or reviewer>

    Tradeoffs a senior engineer must discuss

    Technical tradeoff

    Tapeout is an auditable decision backed by tagged artifacts. Explain not only the preferred fix, but what margin or schedule you are spending to get it.

    Cross-team tradeoff

    • What must RTL, synthesis, CAD, STA, DFT, package, IP, or foundry agree to before this decision is final?

    • Which artifact becomes the source of truth after the decision: report, waiver, manifest, ECO script, or methodology deck?

    • What is the cost of being wrong: one rerun, ECO churn, mask risk, performance loss, or silicon escape?

    Leadership communication

    Diagram
    "The current blocker is <metric> in <corner/mode/stage>. The leading cause is <mechanism>. I recommend <fix> because it is bounded and reversible. The regression surface is <domains>. If it fails, we escalate to <owner> with <evidence>."

    Key takeaways

    • Always connect the concept back to a measurable signoff artifact.

    • A fix is not complete until you can name the regression checks.

    Common pitfalls

    • Optimizing by habit instead of reading the current report.

    • Forgetting that a local fix can regress timing, routing, power, or PV elsewhere.

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    See also

    • Handoff to Foundry Operations — Mechanism
    • Handoff to Foundry Operations — Reports & Metrics
    • Handoff to Foundry Operations — Debug Playbook