yield recovery

Yield Recovery is the process of restoring yield after a yield excursion or systematic yield drop — involving rapid root cause analysis, corrective action, re-qualification, and ramp-back to target yield levels, minimizing the total yield loss impact on production.

Yield Recovery Process

• Detection: SPC alerts, lot disposition failures, or inline inspection alarms signal the yield drop.
• Containment: Hold affected lots, quarantine suspect tools, implement 100% inspection — prevent further damage.
• Root Cause: Failure analysis (FA), defect review (DR), and engineering investigation to identify the cause.
• Corrective Action: Fix the root cause — recipe adjustment, tool maintenance, material change, design fix.
• Verification: Process qualification wafers confirm the fix — yield returns to target.

Why It Matters

• Speed: Faster recovery = less product loss — every hour of low yield costs thousands of dollars in lost production.
• Cost: A 5% yield drop for one week at 10K WSPM = hundreds of lost die — potentially millions in revenue impact.
• Prevention: Post-recovery analysis leads to preventive measures — documentation prevents recurrence.

Yield Recovery is manufacturing triage — rapidly diagnosing and fixing yield drops to minimize production losses and restore full manufacturing capability.