Optical metrology model optimization for repetitive structures
US7355728B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 2005 |
| Grant date | Apr 8, 2008 |
| Priority date | — |
| Expiry date | Mar 8, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/705
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical metrology model for a repetitive structure is optimized by selecting one or more profile parameters using one or more selection criteria. One or more termination criteria are set, the one or more termination criteria comprising measures of stability of the optical metrology model. The profile shape features of the repetitive structure are characterized using the one or more selected profile parameters. The optical metrology model is optimized using a set of values for the one or more selected profile parameters. One or more profile parameters of the profile of the repetitive structure are determined using the optimized optical metrology model and one or more measured diffraction signals. Values of the one or more termination criteria are calculated using the one or more determined profile parameters. When the calculated values of the one or more termination criteria do not match the one or more set termination criteria, the selection of the one or more profile parameters and/or the characterization of the profile shape features of the repetitive structure are revised.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.