Integrated lithographic print and detection model for optical CD
US6869739B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 2003 |
| Grant date | Mar 22, 2005 |
| Priority date | — |
| Expiry date | Jun 11, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70683
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of modeling dose and focus response in lithographic imaging to simulate an optical critical dimension (OCD) metrology system creates simulated aerial images of the object pattern to be transferred to a resist film on the substrate at different focus settings of the metrology imaging system. The method then successively creates simulated images, at different exposure dose and focus settings of the metrology imaging system, of the latent and developed image of the object pattern in the resist film on the substrate, and the etched image of the object pattern in the substrate. The method converts the simulated images into polygons having more than four sides and determines the Fourier spectrum of the polygons simulating the images of the object pattern. Using the spectrum of the polygons simulating the images of the object pattern, the method then creates simulated aerial images of the object pattern developed in the resist film, at different dose and focus settings, as viewed by the OCD metrology system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.