Photomask having an internal substantially transparent etch stop layer
US7049034B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 2003 |
| Grant date | May 23, 2006 |
| Priority date | — |
| Expiry date | Jun 1, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/30
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention generally relates, to optical lithography and more particularly relates to the fabrication of transparent or semitransparent phase shifting masks used in the manufacture of semiconductor devices. In particular, the present invention utilizes an internal etch stop layer and either a deposited substantially transparent layer, deposited partially transparent layer or deposited opaque thereon in an otherwise conventional photomask. The photomask of the present invention is used to make semiconductor devices or integrated circuits. In a preferred embodiment of the present invention is directed to an aaPSM comprising: a patterned opaque layer with a first set of at least one light transmitting openings and a second set of at least one light transmitting openings; a deposited substantially transparent layer underlying the opaque layer wherein the deposited substantially transparent layer has corresponding light transmitting openings to each of the openings of the first set of at least one light transmitting openings, a substantially transparent etch stop layer underlying the deposited substantially transparent layer, and a substantially transparent substrate underlyi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.