US4396683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photomask blank provided with a transparent electro-conductive layer
Assignee: KONIAHIEOKU PHOTO INDUSTRY Co Ltd
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Filing: 1981-03-04
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Granted: 1983-08-02
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Expires: 2001-03-04
Abstract
Abstract There is presented a photomask blank provided with a transparent electroconductive layer, comprising a base having (a) a transparent electroconductive material coated thereon, and also having (b) a heavy metal oxide layer laminated on said material (a) in direct contact therewith or through an intermediary light-screening layer of the same heavy metal as in said layer (b).
Inventors
- 👤 Takashi Hatano
- 👤 Akira Maruyama
- 👤 Keiko Hioka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:26
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/38; G03F1/40; G03F1/54; Y; Y10; Y10S; Y10S428/00; Y10S428/913
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
80 words
A photomask blank provided with a transparent electroconductive layer, comprising a base having (a) a transparent electroconductive material coated layer thereon, and also having (b) a heavy metal oxide layer laminated on said material (a) in direct contact therewith or through an intermediary light-screening layer of a heavy metal which is the same heavy metal as that comprised in said heavy metal oxide in said layer (b); each of said layers having a thickness of between 1 A and 1μ.
Claim 2
Dependent Claim
80 words
A photomask blank provided with a transparent electroconductive layer, comprising a base having (a) a transparent electroconductive material coated layer thereon, and also having (b) a heavy metal oxide layer laminated on said material (a) in direct contact therewith or through an intermediary light-screening layer of a heavy metal which is the same heavy metal as that comprised in said heavy metal oxide in said layer (b); each of said layers having a thickness of between 1 A and 1μ.
Claim 3
Dependent Claim
30 words
The photomask blank of claim 1, wherein said transparent electroconductive material (a) is at least one oxide selected from the group consisting of indium oxide, tin oxide and lead oxide.
Claim 4
Dependent Claim
20 words
The photomask blank of claim 1, wherein said heavy metal is one having a specific gravity of 10 or more.
Claim 5
Dependent Claim
27 words
The photomask blank of claim 3, wherein said heavy metal is one having a reflected electron beam intensity ±50% of the reflected electron beam intensity of gold.
Claim 6
Dependent Claim
26 words
The photomask blank of claim 1 or 2, wherein said heavy metal is at least one selected from the group consisting of tungsten, tantalum and molybdenum.
Claim 7
Dependent Claim
45 words
The photomask blank of claim 1 comprising a base having (a) said transparent electroconductive material coated layer thereon, an intermediate layer of a light-screening heavy metal coated on said layer (a) and (b) an oxide of said heavy metal coating said heavy metal intermediate layer.
Claim 8
Dependent Claim
27 words
The photomask blank of claim 1 having said transparent electroconductive material coated layer and a heavy metal oxide layer laminated on said transparent electroconductive material coated layer.
Claim 9
Dependent Claim
32 words
The photomask blank of claim 6 or 7, wherein said transparent electroconductive material (a) is at least one oxide selected from the group consisting of indium oxide, tin oxide and lead oxide.
Claim 10
Dependent Claim
22 words
The photomask blank of claim 6 or 7, wherein said heavy metal is one having a specific gravity of 10 or more.
Claim 11
Dependent Claim
27 words
The photomask blank of claim 9, wherein said heavy metal is one having a reflected electron beam intensity ±50% of the reflected electron beam intensity of gold.
Claim 12
Dependent Claim
24 words
The photomask blank of claim 8, wherein said heavy metal is at least one selected from the group consisting of tungsten, tantalum and molybdenum.
Claim 13
Dependent Claim
14 words
The photomask blank of claim 11, wherein said transparent electroconductive material is indium oxide.
Claim 14
Dependent Claim
14 words
The photomask blank of claim 11, wherein said transparent electroconductive material is tin oxide.
Claim 15
Dependent Claim
14 words
The photomask blank of claim 11, wherein said transparent electroconductive material is lead oxide.
Claim 16
Dependent Claim
12 words
The photomask blank of claim 11, wherein said heavy metal is tungsten.
References Cited (Backward Citations)
US3847659A
Cited
US4251138A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-01 | 1987-01-31 | 1987-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-01 | 1991-01-31 | 1991-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-01 | 1995-01-31 | 1995-08-02 | $7700.00 | Window Closed / Lapsed |