ABF substrate yield also depends heavily on circuit complexity.
The roughly 60% yield mentioned earlier is closer to a relatively simple design. For advanced AI or CPO substrates around 10cm × 10cm, supply-chain feedback suggests yields can fall below 50%. Larger and more complex substrates may be closer to 40%.
That changes material consumption dramatically:
60% yield → 1.67× input per good substrate
50% yield → 2.0×
40% yield → 2.5×
And much of the scrap has already consumed multiple ABF layers and expensive processing steps.
So the real ABF demand equation is increasingly:
Area × Layers × Design Complexity ÷ Yield
This is why a small reallocation of ABF supply cannot solve the shortage. Poor yield itself is becoming a major source of material consumption.