Phase conflict resolution for photolithographic masks
US7083879B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 17, 2001 |
| Grant date | Aug 1, 2006 |
| Priority date | — |
| Expiry date | Nov 22, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70558
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A photolithographic mask used for defining a layer in an integrated circuit, or other work piece, where the layer comprises a pattern including a plurality of features to be implemented with phase shifting in phase shift regions is laid out including for patterns comprising high density, small dimension features, and for “full shift” patterns. The method includes identifying cutting areas for phase shift regions based on characteristics of the pattern. Next, the process cuts the phase shift regions in selected ones of the cutting areas to define phase shift windows, and assigns phase values to the phase shift windows. The phase shift values assigned comprise φ and θ, so that destructive interference is caused in transitions between adjacent phase shift windows having respective phase shift values of φ and θ. In the preferred embodiment, φ is equal to approximately θ+180 degrees. Results of the cutting and assigning steps are stored in a computer readable medium, used for manufacturing a mask, and used for manufacturing an integrated circuit. By identifying the cutting areas based on characteristics of the pattern to be formed, the problem of dividing phase shift regions into phase …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.