Patent · US Expired

Pattern projecting method

US5627625A · kind A · utility

14Cited by
1References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 21, 1994
Grant dateMay 6, 1997
Priority date
Expiry dateOct 21, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/702
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A pattern projecting method is disclosed. The pattern projecting method has the step of illuminating a mask having a fine pattern formed therein with an exposure light and causing a transmitted light of the mask to be incident on a pupil of a projection optical system to project an image of the fine pattern onto a substrate, the illuminating step using an effective light source capable of achieving such light intensity distribution as to provide a predetermined light intensity in a central region of the pupil, a maximum light intensity in plural peripheral regions around the central region, and a light intensity lower than the maximum light intensity in a region connecting the plural regions.

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