Optical proximity correction for phase shifting photolithographic masks
US6721938B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2002 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Sep 26, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/36
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for producing a computer readable definition of photolithographic mask used to define a target pattern is provided. The phase shift mask patterns include phase shift windows, and the trim mask patterns include trim shapes, which have boundaries defined by such sets of line segments. For a particular pair of phase shift windows used to define a target feature in a target pattern, each of the phase shift windows in the pair can be considered to have a boundary that includes at least one line segment that abuts the target feature. Likewise, a complementary trim shape used in definition of the target feature, for example by including a transmissive region used to clear an unwanted phase transition between the particular pair of phase shift windows, includes at least one line segment that can be considered to abut the target feature. Proximity correction is provided by adjusting the position of the at least one line segment on the boundary of a phase shift windows in said pair which abuts the target feature, and by adjusting the position of the at least one line segment on the boundary of the complementary trim shape which abuts the target feature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.