US4363846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photomask and photomask blank
Assignee: Dai Nippon Printing Co Ltd
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Filing: 1981-11-02
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Granted: 1982-12-14
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Expires: 2001-11-02
Abstract
Abstract In a low reflection type photomask (hard mask) having a chromium masking film provided, through or without an intermediary low reflection layer, on a transparent substrate and further having a low reflection layer provided on the chromium layer, use is made of a composite layer containing chromium oxide and chromium nitride as the low reflection layer. The composite layer is substantially equal in etching speed to the chromium film, and the photomask obtained is free from image deterioration caused by protrusions such as visors, burrs, or fractures, as observed in the photomasks of the prior art using chromium oxide films, and also has excellent durability.
Inventors
- 👤 Satoru Kaneki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:56
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/50; G03F1/38; G03F1/46; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24851; Y10T428/24868; Y10T428/24917; Y10T428/24926; Y10T428/26; Y10T428/261
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
40 words
A photomask blank comprising a transparent substrate and a multi-layer masking film provided on the substrate, said multi-layer masking film comprising a layer of chromium and a composite layer of chromium oxide and chromium nitride laminated on said chromium layer.
Claim 2
Dependent Claim
40 words
A photomask blank comprising a transparent substrate and a multi-layer masking film provided on the substrate, said multi-layer masking film comprising a layer of chromium and a composite layer of chromium oxide and chromium nitride laminated on said chromium layer.
Claim 3
Dependent Claim
27 words
A photomask blank according to claim 1, wherein another composite layer of chromium oxide and chromium nitride is interposed between the chromium layer and the transparent substrate.
Claim 4
Dependent Claim
23 words
A photomask blank according to claim 1, wherein the atomic ratio of Cr:N:O in the composite layer is in the range of 1:0.1-0.3:0.8-1.4.
Claim 5
Dependent Claim
33 words
A photomask blank according to claim 1, wherein the composite layer is formed by sputtering or vacuum evaporation using as source a sintered product of mixed powders of chromium oxide and chromium nitride.
Claim 6
Dependent Claim
34 words
A photomask blank according to claim 1, wherein the composite layer is formed by reactive vacuum evaporation or reactive sputtering using chromium as source in an atmosphere of mixed N 2 -O 2 gas.
Claim 7
Dependent Claim
23 words
A photomask blank according to claim 1, wherein the composite layer has a thickness in the range of from 200 to 500 A.
Claim 8
Dependent Claim
40 words
A photomask comprising a transparent substrate and a patternized multi-layer masking film provided on the substrate, said multi-layer masking film comprising a layer of chromium and a composite layer of chromium oxide and chromium nitride laminated on said chromium layer.
Claim 9
Dependent Claim
40 words
A photomask comprising a transparent substrate and a patternized multi-layer masking film provided on the substrate, said multi-layer masking film comprising a layer of chromium and a composite layer of chromium oxide and chromium nitride laminated on said chromium layer.
Claim 10
Dependent Claim
26 words
A photomask according to claim 7, wherein another composite layer of chromium oxide and chromium nitride is interposed between the chromium layer and the transparent substrate.
Claim 11
Dependent Claim
22 words
A photomask according to claim 7, wherein the atomic ratio of Cr:N:O in the composite layer is in the range of 1:0.1-0.3:0.8-1.4.
Claim 12
Dependent Claim
16 words
A photomask according to claim 7, wherein the multi-layer masking film has been patternized by etching.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-12-13 | 1986-06-14 | 1986-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-13 | 1990-06-14 | 1990-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-13 | 1994-06-14 | 1994-12-14 | $7700.00 | Window Closed / Lapsed |