Semiconductor Fab Equipment Manufacturing worked example

Chamber Machining Yield at 68% target machining yield: a worked example

This worked example runs the chamber machining yield numbers for a tougher week than the baseline: 68% target machining yield instead of the typical 95%. Estimate chamber machining yield for semiconductor fab equipment manufacturing using production-ready inputs so teams can track KPI performance and decide whether corrective action is needed.

The inputs for this scenario

  • Machined chambers passing dimensional inspection: 8 count (held at the documented default)
  • Chambers machined this run: 250 count (held at the documented default)
  • Target machining yield: 68 % (the input this scenario stresses; the baseline uses 95)

Working through the calculation

  • The calculation starts from the formula this tool documents: Chamber machining yield rate = chamber machining yield count ÷ total chamber machining yield population × 100.
  • Chamber machining yield rate works out to 3.2 % at these inputs, and this is the headline figure for the scenario.
  • Chamber machining yield gap to target works out to 64.8 points at these inputs.
  • Chamber machining yield count works out to 8 count at these inputs.
  • Total chamber machining yield population works out to 250 count at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where target machining yield sits at 95% and the headline result is 3.2 %, this scenario lands almost exactly on the baseline at 3.2 %.
  • Use it after a machining run when CMM and surface-finish results are in, to judge process capability and scrap. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Chamber machining yield rate: 3.2 % (headline result)
  • Chamber machining yield gap to target: 64.8 points
  • Chamber machining yield count: 8 count
  • Total chamber machining yield population: 250 count

Run it with your numbers

  • To rerun this with your own numbers, open the live Chamber Machining Yield calculator, set target machining yield to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.