Method and apparatus for enhancing signal strength for improved generation and placement of model-based sub-resolution assist features (MB-SRAF)
US8826198B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 2013 |
| Grant date | Sep 2, 2014 |
| Priority date | — |
| Expiry date | May 13, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/36
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Model-Based Sub-Resolution Assist Feature (SRAF) generation process and apparatus are disclosed, in which an SRAF guidance map (SGM) is iteratively optimized to finally output an optimized set of SRAFs as a result of enhanced signal strength obtained by iterations involving SRAF polygons and SGM image. SRAFs generated in a prior round of iteration are incorporated in a mask layout to generate a subsequent set of SRAFs. The iterative process is terminated when a set of SRAF accommodates a desired process window or when a predefined process window criterion is satisfied. Various cost functions, representing various lithographic responses, may be predefined for the optimization process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.