Patent · US Active

Method, program product and apparatus for performing double exposure lithography

US7681171B2 · kind B2 · utility

8Cited by

10References

23Claims

0Family size

Assignee

ASML Masktooks B.V. · NL

Inventors

Jang Fung Chen · Cupertino, US
Duan-Fu Stephen Hsu · Fremont, US
Douglas Van Den Broeke · Sunnyvale, US

Key dates

Filing date	Apr 12, 2006
Grant date	Mar 16, 2010
Priority date	—
Expiry date	Feb 9, 2028

Classification

Technology area (CPC G)Physics
CPC primaryG06F2119/18
WIPO fieldComputer technology
WIPO sectorElectrical engineering

Abstract

A method of generating complementary masks based on a target pattern having features to be imaged on a substrate for use in a multiple-exposure lithographic imaging process. The method includes the steps of: defining an initial H-mask corresponding to the target pattern; defining an initial V-mask corresponding to the target pattern; identifying horizontal critical features in the H-mask having a width which is less than a predetermined critical width; identifying vertical critical features in the V-mask having a width which is less than a predetermined critical width; assigning a first phase shift and a first percentage transmission to the horizontal critical features, which are to be formed in the H-mask; and assigning a second phase shift and a second percentage transmission to the vertical critical features, which are to be formed in the V-mask. The method further includes the step of assigning chrome to all non-critical features in the H-mask and the V-mask. The non-critical features are those features having a width which is greater than or equal to the predetermined critical width. The non-critical features are formed in the H-mask and the V-mask utilizing chrome. The target…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.