Patent · US Expired

Method of lithography using vacuum ultraviolet radiation

US6605815B2 · kind B2 · utility

4Cited by
8References
14Claims
0Family size

Inventor

Key dates

Filing dateMar 11, 2002
Grant dateAug 12, 2003
Priority date
Expiry dateMar 11, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70575
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method of vacuum ultraviolet (VUV) lithography in which an irradiating wavelength is selected to be in a region of low absorption in air, e.g., one in the vicinity of a local minimum in an oxygen absorption spectrum. In one embodiment, a lithographic exposure wavelength is advantageously selected between 121.0 nm to 122.0 nm, preferably at about 121.6 nm, corresponding to an absorption window in the oxygen spectrum. This method relaxes the otherwise stringent vacuum and inert gas purge requirement imposed on a VUV lithographic tool.

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