Methods for improved monitor and control of lithography processes
US9188974B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 2011 |
| Grant date | Nov 17, 2015 |
| Priority date | — |
| Expiry date | Feb 20, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B19/41875
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Various computer-implemented methods are provided. One method includes determining errors across a field of a lens of a lithography system based on wafer measurements. In addition, the method includes separating the errors into correctable and non-correctable errors across the field. The errors may include dose errors, focus errors, or dose and focus errors. In another embodiment, the method may include determining correction terms for parameter(s) of the lithography system, which if applied to the parameter(s), the correctable errors would be eliminated resulting in approximately optimal imaging performance of the lithography system. Another method includes controlling one or more parameters of features within substantially an entire printed area on a product wafer using a limited number of wafer measurements performed on a test wafer. The wafer measurements may be performed on a first feature type, and the features that are controlled may include a second, different feature type.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.