Patent · US Expired

Lithography reflective mask

US6178221A · kind A · utility

38Cited by
1References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 4, 1998
Grant dateJan 23, 2001
Priority date
Expiry dateDec 4, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70233
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A reflective lithography mask (12) including a substrate (40); a reflective coating (42); a plurality of absorbing blocks (44) covering certain regions of the reflective coating (42) in a manner corresponding to a desired circuit pattern; and a plurality of buffer blocks (46) situated between the covered regions of the reflective coating and the absorbing blocks. The buffer blocks (46) are made of an electrically conducting material, such as carbon in graphite form; tin oxide (and materials based on this compound) and/or indium oxide (and materials based on this compound). Since the buffer material is electrically conducting, rather than insulating, the risk of electrostatic discharge damage is reduced.

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