Advanced-Packaging Chiplet Qualification Director — Automotive Compute

The mandate

A vehicle-compute platform combines logic, safety island, memory and high-speed interfaces from different process nodes on an organic substrate with a silicon bridge. Early assemblies meet room-temperature performance but show warpage-driven attach loss, intermittent die-to-die links and divergent ageing between suppliers. The defined problem is to construct qualification evidence for the complete package rather than stacking individually favourable component reports that do not represent automotive mission profiles.

The deliverables are a package failure-mechanism map, known-good-die strategy, simulation-to-measurement correlation, assembly control plan, accelerated-stress matrix, interface-margin evidence, supplier deviation route and production qualification dossier. Each artefact must bind die revision, substrate lot, assembly recipe, thermal solution and test coverage. The design must expose interaction risks without reopening every supplier’s proprietary silicon qualification.

Four milestones govern the engagement: baseline correlation and sample sufficiency agreement by 30 October 2026; controlled assembly splits plus known-good-die decisions by 18 December; combined thermal, mechanical and electrical stress evidence by 19 February 2027; and accepted dossier, manufacturing limits and trained client owners by 30 April. Each milestone includes physical sample evidence from the declared production path.

Acceptance requires quality to trace every safety-relevant claim to representative hardware, manufacturing to reproduce the approved process window, and platform engineering to demonstrate interface margin after stress at temperature extremes. The client sponsor returns one consolidated defect register within seven working days. Passing individual die tests, simulation agreement without measured correlation or a supplier waiver lacking vehicle consequence cannot close a qualification question.

The client provides design rules, package models, die revisions, wafer-test data, assembly genealogy, reliability chambers, vehicle mission profiles, failure-analysis access and empowered supplier representatives. It funds agreed sample builds and declares safety classification before test design. The director cannot release product, alter vehicle safety goals, compel proprietary supplier disclosure or approve deviations outside the project’s documented acceptance chain.

Why this is external work

No single supplier owns the interaction among heterogeneous die, bridge, substrate, attach, thermal stack and vehicle duty cycle. Internal teams also carry schedule commitments that make it difficult to reject a locally passing component. An independent qualification director can integrate the physical evidence and finish when the client accepts bounded manufacturing limits and residual risks.

What you will own

• Build the interaction-level failure model spanning warpage, interconnect fatigue, delamination, thermal gradients, power cycling and die-to-die margin.
• Define known-good-die evidence and coverage allocation across wafer sort, assembly test, system test and vehicle-level diagnostics.
• Reconcile finite-element, thermal and signal-integrity predictions against measured package behaviour across representative build genealogies.
• Govern sample matrices by mechanism, corner, supplier, lot and mission profile rather than convenient chamber availability.
• Challenge assembly windows for bonding, underfill, mould, substrate handling, rework and thermal-interface application using statistical evidence.
• Translate qualification anomalies into containment, additional test, design change, supplier concession or explicitly owned residual risk.
• Deliver the accepted qualification dossier, production control limits, deviation logic and client-led review rehearsal.

Candidate qualifications

• Directed heterogeneous-integration or advanced-package qualification for automotive, aerospace, networking or high-reliability compute products.
• Can show a package interaction failure missed by component-level qualification and resolved through representative physical evidence.
• Understands chiplets, interposers or bridges, micro-bumps, substrates, warpage, thermo-mechanical fatigue and high-speed interface margin.
• Has governed known-good-die strategy where added test cost competed with expensive assembled-package yield loss.
• Worked across guarded supplier boundaries while preserving traceable system-level acceptance and change control.
• Converts reliability data into manufacturable limits instead of broad requests for more samples or indefinite stress testing.

Non-negotiables

• Will attend the Dresden, Grenoble and Penang qualification windows stated in the milestone plan.
• Has personally accepted or rejected production-representative heterogeneous packages using post-stress electrical evidence.
• Accepts milestone rejection when die, substrate, assembly or test genealogy is not traceable to the claimed configuration.
• Will disclose foundry, OSAT, substrate, EDA and automotive-customer relationships before mobilisation.

1. 49 words maximum. Which package-level failure escaped otherwise valid qualification of each constituent die?
2. 49 words maximum. How would you size a stress matrix when assembled samples are scarce and configuration choices multiply?
3. 49 words maximum. What evidence makes a supplier deviation acceptable for a safety-relevant automotive package?