Metrology system optimization for parameter tracking
US9255877B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 2014 |
| Grant date | Feb 9, 2016 |
| Priority date | — |
| Expiry date | May 15, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/213
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and systems for evaluating the capability of a measurement system to track measurement parameters through a given process window are presented herein. Performance evaluations include random perturbations, systematic perturbations, or both to effectively characterize the impact of model errors, metrology system imperfections, and calibration errors, among others. In some examples, metrology target parameters are predetermined as part of a Design of Experiments (DOE). Estimated values of the metrology target parameters are compared to the known DOE parameter values to determine the tracking capability of the particular measurement. In some examples, the measurement model is parameterized by principal components to reduce the number of degrees of freedom of the measurement model. In addition, exemplary methods and systems for optimizing the measurement capability of semiconductor metrology systems for metrology applications subject to process variations are presented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.