Patent · US Expired

Raster-scan photolithographic reduction system

US5982475A · kind A · utility

27Cited by
17References
37Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 30, 1997
Grant dateNov 9, 1999
Priority date
Expiry dateSep 30, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70058
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A reduction photolithographic scanning system uses a reduction lens with a circular image field that is shaped to an irregular hexagonal configuration affording different effective scanning widths so that the full area of a microcircuit image can be scanned onto a substrate in an integer number of overlapping scans. This minimizes the number of scans required for each image area and maximizes the total image area that can be scanned per time unit.

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