US3619387A
Expired / Lapsed
US
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Technique for the fabrication of thin film capacitor including lead dioxide conductive films
Assignee: AT&T Inc
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Filing: 1970-01-27
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Granted: 1971-11-09
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Expires: 1990-01-27
Abstract
Abstract Lead dioxide films are deposited upon a substrate with mechanical properties such as to permit fabrication of capacitors in which they are used as the solid electrolyte over a metal oxide dielectric. The lead dioxide is produced by the oxidation of a divalent lead compound in solution by means of a persulfate.
Inventors
- 👤 Wolfgang Friedrich Herma Mindt
- 👤 George Ignatius Parisi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:11
CPC Classifications
H; H01; H01G; H01G9/00; H01G9/0029; H01G9/0036; C; C01; C01G; C01G21/00; C01G21/02; C01G21/08; H01G9/004; H01G9/022; H01G9/025
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
35 words
Process in accordance with claim 1 wherein the solution employed to subsequently contact said surface consists essentially of a solution of a divalent lead compound and a persulfate at a pH between 10 and 12.
Claim 2
Dependent Claim
153 words
A Process for the fabrication of a solid electrolytic capacitor comprising the steps of (a) partially anodizing a film-forming metal, thereby producing a dielectric oxide layer, and (b) depositing a counterelectrode upon and in intimate contact with said dielectric layer characterized in that there is deposited intermediate said dielectric oxide layer and said counterelectrode, a layer of lead dioxide formed by first nucleating a thin film of lead dioxide upon said dielectric oxide layer by reacting an acidic first solution of ammonium acetate, lead acetate and a soluble silver salt with a compound selected from the group consisting of the persulfates of sodium, potassium and ammonium and then growing a layer of lead dioxide of a thickness within the range of 4,000-6,000 angstroms upon said nucleated layer by reacting a second solution comprising ammonium acetate, lead acetate and a persulfate selected from the group consisting of the persulfates of sodium, potassium and ammonium.
Claim 3
Dependent Claim
20 words
Process in accordance with claim 3 wherein said first and second solutions have a pH within the range of 5.0-6.9.
Claim 4
Dependent Claim
18 words
Process in accordance with claim 3 wherein said second solution has a pH within the range of 10-12.
Claim 5
Dependent Claim
54 words
Process in accordance with claim 3 wherein the molarity of components of said solutions is as follows: ammonium acetate 1-8 lead acetate 0.1-1 silver salt 5 X 10 5-5 X 10 4 persulfate 1-2 the upper limit of concentration of the lead acetate corresponding with the upper limit of concentration of the ammonium acetate.
References Cited (Backward Citations)
US3466230A
Cited
US3415722A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |