Patent · US Active

Reflection mode photomask and method of making

US11735421B2 · kind B2 · utility

1Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 8, 2022
Grant dateAug 22, 2023
Priority date
Expiry dateFeb 8, 2042

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/0276
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method of manufacturing a reticle includes depositing an etch stop layer over a substrate; and depositing an absorber layer over the etch stop layer. The method further includes depositing a hard mask layer over the absorber layer, wherein the hard mask layer includes tantalum. The method includes patterning the hard mask layer. The method further includes performing a first etch process to remove a portion of the absorber layer underneath the patterned hard mask. The method includes performing a second etch process to partially remove a portion of a thickness of an etch stop layer underneath the removed portion of the absorber layer, wherein performing the third etch process comprises maintaining a remaining thickness of the etch stop layer underneath the removed portion of the absorber. The method further includes maintaining the remaining thickness of the etch stop layer through a termination of the method of manufacturing the reticle.

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