Hello,

I'm Darshan Hiranandani, working on analyzing the bow profile of processed wafers, and I need some guidance on determining how well a wafer meets the pre-defined specification.

I've created an ideal profile based on the median of 500 previous wafers and established tolerance limits at ?2 sigma (0.025 and 97.5 percentiles).

What I need is a way to:

Measure how well the new wafer profile fits within the tolerance window.
Quantify the distance from the tolerance limits and the distance from the ideal profile.
Possibly use a Ppk-like value or similar metric to express how well the profile conforms.

Does anyone have experience with this, or any tools/methods you?ve used to quantify conformance to a specification? Any advice or insights would be extremely helpful.

Thank you in advance!
Regards
Darshan Hiranandani