Method for measuring and calibrating centroid of coarse stage of photolithography tool
US9519231B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 2012 |
| Grant date | Dec 13, 2016 |
| Priority date | — |
| Expiry date | Sep 6, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70725
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for measuring and calibrating a centroid of a coarse stage of a photolithography tool by means of measuring an offset of the centroid relative to a midpoint of the coarse stage is disclosed. The method includes: individually performing closed-loop controls on parameters of the three degrees of freedom X, Y, and Rz of the coarse stage and converting the parameters into coordinates in a coordinate system of the coarse stage (601); for each of the X and Y directions, estimating a range for the centroid (604), equally dividing the range into N parts (605), and designating each dividing point as an eccentricity (605); obtaining N Rz direction positional deviations by conducting a compensation calibration and a calibration calculation based on each corresponding eccentricity (606-611); comparing a minimum of the N positional deviations with a preset Rz-direction positional deviation threshold (613), completing the measurement if the latter is greater (614), and otherwise designating a range between the eccentricities adjacently in front of and behind the eccentricity corresponding to the minimum positional deviation as a new range for the centroid (616-617) and repeating the mea…
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