Defect Density To Yield Calculator

Work out defect density to yield instantly with clear inputs, formula shown and shareable results.

About Defect Density To Yield Calculator

Two yield mechanisms multiply: random defect yield e^(-A x D0) and cumulative process yield, which is per-layer yield raised to the number of critical layers. Twelve layers at 99.5% each already costs 5.8%, which is why layer count reduction is as valuable as defect reduction.

Formula

Combined yield

Y = e^(-A D0) x (layer yield)^layers

Worked example

With the default values below, Defect Density To Yield Calculator returns Overall yield of 77.094%. Change any input above and every figure here is recalculated in your browser.

Inputs used

Defect density: 0.2 defects/cm²
Die area: 100 mm²
Critical mask layers: 12 layers
Per-layer yield: 99.5 %

Results

Overall yield: 77.094% %
Yield from defect density: 81.873% %
Cumulative process yield: 94.162% %
Average defects per die: 0.2000 defects

Step by step

1Values used
2Combined yield
3Overall yield= 77.094 %
4Yield from defect density= 81.873 %
5Cumulative process yield= 94.162 %
6Average defects per die= 0.2000 defects

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why does per-layer yield matter so much?

Because it compounds. At 99% per layer, 30 layers gives only 74% overall even with zero random defects.

What is D0 in a mature process?

Typically 0.05-0.3 defects per cm2 for a mature node, rising sharply during ramp-up of a new process.