Method and apparatus for performing model based placement of phase-balanced scattering bars for sub-wavelength optical lithography
US7550235B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 2004 |
| Grant date | Jun 23, 2009 |
| Priority date | — |
| Expiry date | Aug 22, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/36
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of generating a mask design having optical proximity correction features disposed therein. The methods includes the steps of obtaining a desired target pattern having features to be imaged on a substrate; determining a first interference map based on the target pattern, which defines areas of constructive interference between at least one of the features to be imaged and a field area adjacent the at least one feature; placing a first set of assist features having a first phase in the mask design based on the areas of constructive interference defined by the first interference map; determining a second interference map based on the first set of assist features, which defines areas of constructive interference between assist features of the first set of assist features and a field area adjacent at least one of the assist features of the first set of assist features; and placing a second set of assist features having a second phase in the mask design based on the areas of constructive interference defined by the second interference map, wherein the first phase does not equal the second phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.