Patent · US Expired

Exposure mask

US5536604A · kind A · utility

19Cited by
1References
37Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 24, 1995
Grant dateJul 16, 1996
Priority date
Expiry dateJan 24, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F1/32
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An exposure mask according to the invention comprises a light-transmissive substrate, and mask patterns formed on the light-transmissive substrate, and including transparent phase shift patterns and translucent phase shift patterns, each of the translucent phase shift patterns having a phase difference of at least 180.degree. for exposure light corresponding to an optical path difference between a transparent portion of the light-transmissive substrate and a transparent portion of the transparent phase shift pattern, the transparent phase shift patterns and translucent phase shift patterns overlapping with each other, wherein the mask patterns include pattern groups each having a first region consisting of an exposed portion of the light-transmissive substrate, a second region adjacent to the first region, in which only a corresponding one of the translucent phase shift patterns exists, a third region adjacent to the second region, in which a corresponding one of the transparent phase shift patterns is laminated on the corresponding translucent phase shift pattern, and a fourth region adjacent to the third region, in which only the corresponding transparent phase shift pattern exis…

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