Scatterometry-based imaging and critical dimension metrology
US9494535B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 19, 2015 |
| Grant date | Nov 15, 2016 |
| Priority date | — |
| Expiry date | May 13, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and systems for performing measurements of semiconductor structures and materials based on scatterometry measurement data are presented. Scatterometry measurement data is used to generate an image of a material property of a measured structure based on the measured intensities of the detected diffraction orders. In some examples, a value of a parameter of interest is determined directly from the map of the material property of the measurement target. In some other examples, the image is compared to structural characteristics estimated by a geometric, model-based parametric inversion of the same measurement data. Discrepancies are used to update the geometric model of the measured structure and improve measurement performance. This enables a metrology system to converge on an accurate parametric measurement model when there are significant deviations between the actual shape of a manufactured structure subject to model-based measurement and the modeled shape of the structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.