Patent US5740804A successfully refreshed from Google Patents.
Patent EP0082977A1 successfully refreshed from Google Patents.
EP0082977A1
Expired / Lapsed
EP
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Integrated circuit photomask
Assignee: International Business Machines Corp
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Filing: 1982-12-02
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Granted: —
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Expires: 2002-12-02
Abstract
Abstract The invention relstes to an integrated circuit photomask. The photomask it formed of a transparent dielectric substrate (1), such as glass and quartz based substrates, and has a conductive surface adjacent region (3), which is patterned with sequential overcoatings of a composite chrome oxide layer (5) and a chrome film (6). The mask comprises a combination of varied reflectivities to provide proper densities for the opaque areas of the mask.
Inventors
- 👤 Bernt Narken
- 👤 Henry Carl Schick
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 04:56
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/20; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24851; Y10T428/24868; Y10T428/24917; Y10T428/24926; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/24975; Y10T428/24992
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
64 words
Photomask comprised of a transparent dielectric (1) having a transparent conductive zone (3) therein coextensive with and adjacent a surface (4) thereof, and mask on said surface having a predetermined pattern of opaque extensions of a first film (5) on said surface and of a second film (6) on said first film delineating a desired pattern of complementary transparent areas (10) through substrate (1).
Claim 2
Dependent Claim
64 words
Photomask comprised of a transparent dielectric (1) having a transparent conductive zone (3) therein coextensive with and adjacent a surface (4) thereof, and mask on said surface having a predetermined pattern of opaque extensions of a first film (5) on said surface and of a second film (6) on said first film delineating a desired pattern of complementary transparent areas (10) through substrate (1).
Claim 3
Dependent Claim
15 words
Photomask of claim 1 wherein substrate (1) is selected from glass and quartz based substrates.
Claim 4
Dependent Claim
23 words
Photomask of claims 1 and 2 wherein zone (3) comprises a region doped with additives selected from the group of tin and indium.
Claim 5
Dependent Claim
20 words
, Photomask of claim 3 wherein zone (3) comprises a tin doped region, said tin displacing oxygen in substrate (1).
Claim 6
Dependent Claim
13 words
Photomask of claim 1 wherein first film (5) has a reflectance of 33%+6%.
Claim 7
Dependent Claim
35 words
Photomask of claims 1 and 5 wherein second film (6) has a minimum reflectance of 50%, with the total reflectance of first film (5) and second film (6) in the range of 27 to 39%.
Claim 8
Dependent Claim
20 words
Photomask of claim 1 wherein first and second film (6) have a combined minimum optical density of at least 3.
Claim 9
Dependent Claim
46 words
8 . Photomask of claim 1 wherein the predetermined pattern comprises a first film (5) selected from the group of Cr 2 O 3 , Cr 2 O 5 , and Cr 2 O 7 and a second film (6) of chromium on said first film.
Claim 10
Dependent Claim
84 words
Photomask adapted for E-beam lithography comprised of a transparent dielectric substrate (1) having a first surface (4) adjacent coextending region (3) doped with tin converting said region into a transparent electrically conductive layer, with said region spaced from the opposite surface of substrate (1) a first film (5) on first surface (4) adjacent region (3), with said film selected from the group consisting of Cr 2 0 3 and Cr 2 O 5 ; and a chromium second film (6) over first film (5).
Claim 11
Dependent Claim
84 words
Photomask adapted for E-beam lithography comprised of a transparent dielectric substrate (1) having a first surface (4) adjacent coextending region (3) doped with tin converting said region into a transparent electrically conductive layer, with said region spaced from the opposite surface of substrate (1) a first film (5) on first surface (4) adjacent region (3), with said film selected from the group consisting of Cr 2 0 3 and Cr 2 O 5 ; and a chromium second film (6) over first film (5).
Claim 12
Dependent Claim
26 words
Photomask of claim 9 wherein first and second films (5,6) are coextensively delineated in a predetermined pattern of opaque and transparent areas (10) on substrate (1).
References Cited (Backward Citations)
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