Metrology method, apparatus and computer program
US10551172B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 17, 2018 |
| Grant date | Feb 4, 2020 |
| Priority date | — |
| Expiry date | Apr 19, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/7065
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed herein is a metrology method, and an associated metrology apparatus, the metrology method includes measuring a target formed in at least two layers on a substrate by a lithographic process and capturing at least one corresponding pair of non-zeroth diffraction orders, for example in an image field, to obtain measurement data. A simulation of a measurement of the target as defined in terms of geometric parameters of the target, the geometric parameters including one or more variable geometric parameters, is performed and a difference between the measurement data and simulation data is minimized, so as to directly reconstruct a value for each of the one or more variable geometric parameters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.