dppm

DPPM (Defective Parts Per Million) is the primary quality metric measuring the rate of defective devices shipped to customers — calculated as $DPPM = \frac{\text{defective parts}}{\text{total shipped}} \times 10^6$, representing the outgoing quality level of manufactured semiconductor products.

DPPM Context

• Automotive: Target <1 DPPM — extremely stringent, requiring multiple layers of screening and testing.
• Consumer: Target <10-50 DPPM — less stringent than automotive but still demanding.
• Industrial: Target <5-20 DPPM — varies by application criticality.
• Calculation Period: Typically measured quarterly or annually — smooths statistical variation.

Why It Matters

• Customer Expectation: Customers specify maximum acceptable DPPM — failure to meet targets risks losing business.
• Cost of Quality: Lower DPPM requires more testing, screening, and inspection — balance quality cost with target level.
• Improvement: DPPM improvement requires systematic defect reduction, test coverage improvement, and burn-in optimization.

DPPM is the quality scorecard — the universal metric for semiconductor outgoing quality measured in defective parts per million shipped.