Patent · US Expired

Photomask, aberration correction plate, exposure apparatus, and process of production of microdevice

US6653024B1 · kind B1 · utility

18Cited by
8References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 10, 2000
Grant dateNov 25, 2003
Priority date
Expiry dateMay 10, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70866
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A photomask including a substrate comprised of fluorite (calcium fluoride (CaF2)) and protective films comprised of chrome (Cr), chromium oxide (Cro), silicon oxide (SiO2 or SiO), etc. and formed at regions, other than the pattern region where the pattern to be transferred is formed, which contact other members when transporting the photomask or using it for exposure.

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