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US4510222A Expired / Lapsed US ⏱️ 0.0 years remaining

Photomask with corrected white defects

Assignee: Hitachi Ltd
•
Filing: 1983-05-19
•
Granted: 1985-04-09
•
Expires: 2003-05-19
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Abstract

Abstract A photomask with white defects that have corrected with a film comprising a mixture of silver and tantalum oxide. The film has a good resistance to chemicals.

Inventors

  • 👤 Masaaki Okunaka
  • 👤 Katsuro Mizukoshi
  • 👤 Mikio Hongo
  • 👤 Tateoki Miyauchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 18:39
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/68; G03F1/72; G03F1/54; Y; Y10; Y10S; Y10S430/00; Y10S430/139; Y10S430/146

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 61 words
A photomask with corrected white defects which comprises the white defects having been coated with a film comprising a mixture of silver and tantalum oxide to form a light-shielding film for the white defects which is sufficiently resistant to chemicals such that the photomask can be washed without dissolution of said film and which exhibits good adhesion to the photomask substrate.
Claim 2
Dependent Claim 61 words
A photomask with corrected white defects which comprises the white defects having been coated with a film comprising a mixture of silver and tantalum oxide to form a light-shielding film for the white defects which is sufficiently resistant to chemicals such that the photomask can be washed without dissolution of said film and which exhibits good adhesion to the photomask substrate.
Claim 3
Dependent Claim 175 words
A photomask with corrected white defects according to claim 1 wherein the film comprising a mixture of silver and tantalum oxide is obtained by applying a composition composed of (a) silver nitrate, (b) at least one compound selected from the group of tantalum complexes described by general formulas (1) to (3) Ta(OR.sub.1).sub.l (R.sub.2 COCR.sub.3 COR.sub.4).sub.5-l ( 1) Ta(OR.sub.1).sub.m (OCOR.sub.5).sub.5-m ( 2) Ta(OR.sub.1).sub.n (R.sub.2 COCR.sub.3 COR.sub.4).sub.k (OCOR.sub.5).sub.5-n-k ( 3) where R 1 , R 3 , and R 5 are alkyl groups of 1 to 18 carbon atoms, R 2 and R 4 are alkyl or alkoxy groups of 1 to 18 carbon atoms, and l, m, n, and k are 0 or integers from 1 to 5, with n+k≦5, and (c) a solvent, said components (a) and (b) being combined in a mixing ratio by mole falling with the range described in Eq. (I) below ##EQU3## to at least the white defects of a photomask pattern, and irradiating the defects with a beam of light, thereby bringing about deposition of the silver and tantalum oxide.
Claim 4
Dependent Claim 21 words
A photomask with corrected white defects according to claim 2 wherein a multibasic carboxylic acid is also added to the composition.
Claim 5
Dependent Claim 39 words
A photomask with corrected white defects according to claim 2 or 3 wherein the solvent is a mixture of the nitrile substitution product of an aliphatic hydrocarbon and either an alcohol or the monoalkyl ether of an ethylene glycol.
Claim 6
Dependent Claim 54 words
A photomask with corrected white defects according to claim 3 wherein the carboxylic acid is at least one compound selected from the group consisting of malonic acid, methylmalonic acid, succinic acid, methylsuccinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, itaconic acid, maleic acid, citraconic acid, ethylmaleic acid, and mesaconic acid.
Claim 7
Dependent Claim 19 words
A photomask with corrected white defects according to claim 2 wherein said beam of light is a laser beam.
Claim 8
Dependent Claim 34 words
A photomask with corrected white defects according to claim 2 wherein said composition is applied to at least the white defects by spin coating the composition on the photomask to provide a uniform film.
Claim 9
Dependent Claim 29 words
A photomask with corrected white defects according to claim 3 wherein said silver nitrate and said multibasic carboxylic acid are used in a mixing ratio, in moles, of: ##EQU4##
Claim 10
Dependent Claim 65 words
A photomask with corrected white defects according to claim 4 wherein said alcohol is selected from the group consisting of methanol, ethanol and isopropanol; the monoalkyl ether of ethylene glycol is selected from the group consisting of ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; and said nitrile substitution product of an aliphatic hydrocarbon is selected from the group consisting of acetonitrile and propionitrile.

References Cited (Backward Citations)

US4023961A Cited
US4340654A Cited
US4444801A Cited
JPS57206026A Cited
JPS586128A Cited
US4463073A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-04-08 1988-10-08 1989-04-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-04-08 1992-10-08 1993-04-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-04-08 1996-10-08 1997-04-09 $7700.00 Window Closed / Lapsed

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