Optical determination of pattern feature parameters using a scalar model having effective optical properties
US7212293B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 2004 |
| Grant date | May 1, 2007 |
| Priority date | — |
| Expiry date | Jun 23, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/55
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Optical characterization of lateral features of a pattern is provided. A plane-wave optical response is calculated for each feature. At least one of these plane-wave responses is calculated from an effective optical property (e.g., a waveguide modal refractive index). Such effective optical properties depend on feature geometry and on intrinsic material optical properties. The plane-wave responses for each feature are combined to generate a modeled pattern response. By fitting the modeled pattern response to a corresponding measured pattern response, estimates for pattern feature parameters are obtained. The use of an effective optical property improves model accuracy, especially for features having a size on the order of a wavelength or less, without significantly increasing computation time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.