Patent · US Expired

Microlithographic structures and method of fabrication

US7008738B2 · kind B2 · utility

5Cited by
11References
29Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 18, 2004
Grant dateMar 7, 2006
Priority date
Expiry dateMay 18, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F1/29
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method of formulating and fabricating a mask pattern and resulting mask for forming isolated or closely spaced contact holes in an integrated circuit. The mask has a transparent mask substrate and patterned regions of attenuating phase shift material and opaque, partially transmissive or transparent material arranged to reduce the effect of side lobes and improve depth of focus. The rims, frames and outrigger patterns for the attenuating phase shift material and opaque, partially transmissive or transparent material are determined according to calculations performed on a processor with imaging software for various optical conditions and exposed feature criteria.

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