Semiconductor Fab Equipment Manufacturing worked example

Chamber Machining Yield at 99% target machining yield: a worked example

This scenario runs the chamber machining yield calculation on the strong side: 99% target machining yield, with every other input held at its documented default. Use it when chamber machining yield in semiconductor fab equipment manufacturing needs a clean rate and gap-to-target you can put on a tier board.

The inputs for this scenario

  • Machined chambers passing dimensional inspection: 8 count (unchanged)
  • Chambers machined this run: 250 count (unchanged)
  • Target machining yield: 99 % (raised for this scenario; the documented default is 95)

Working through the calculation

  • Applying the documented formula (Chamber machining yield rate = chamber machining yield count ÷ total chamber machining yield population × 100) to the inputs above produces each figure below.
  • At this operating point the engine returns 3.2 % for chamber machining yield rate, the number this scenario is built around.
  • At this operating point the engine returns 95.8 points for chamber machining yield gap to target.
  • At this operating point the engine returns 8 count for chamber machining yield count.
  • At this operating point the engine returns 250 count for total chamber machining yield population.

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. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Chamber machining yield rate: 3.2 % (headline result)
  • Chamber machining yield gap to target: 95.8 points
  • Chamber machining yield count: 8 count
  • Total chamber machining yield population: 250 count

Run it with your numbers

  • Every input above is editable in the live Chamber Machining Yield calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.