Patent US4496435A successfully refreshed from Google Patents.
US4496435A
Expired / Lapsed
US
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Method of manufacturing thin film circuits
Assignee: NEC Corp
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Filing: 1984-02-07
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Granted: 1985-01-29
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Expires: 2004-02-07
Abstract
Abstract A thin film circuit including resistor elements and capacitor elements is prepared by forming a tantalum film for capacitor on an insulating substrate, forming a tantalum film for resistor over the substrate, covering a predetermined region of the tantalum resistor film with a titanium film, heat treating a resulting assembly, removing the titanium film, and then covering the predetermined region with a metal film to provide ohmic contact therebetween.
Inventors
- 👤 Keiji Harada
- 👤 Akio Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:12
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/01; H10D86/00; H10D86/01
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
54 words
A method of manufacturing a thin film circuit comprising the steps of: forming a tantalum film on insulating substrate; covering a predetermined region of said tantalum film with a titanium film; heat treating a resulting assembly; removing said titanium film; and covering said predetermined region with a metal film to provide ohmic contact therebetween.
Claim 2
Independent Claim
54 words
A method of manufacturing a thin film circuit comprising the steps of: forming a tantalum film on insulating substrate; covering a predetermined region of said tantalum film with a titanium film; heat treating a resulting assembly; removing said titanium film; and covering said predetermined region with a metal film to provide ohmic contact therebetween.
Claim 3
Dependent Claim
16 words
The method according to claim 1 wherein said metal film comprises nichrome, palladium and gold layers.
Claim 4
Independent Claim
171 words
A method of forming a thin film circuit including capacitor elements and resistor elements which are formed on the same insulating substrate, comprising the steps of: forming a tantalum film for capacitor on said insulating substrate; etching said tantalum capacitor film to form a predetermined circuit pattern; anodizing a portion of said tantalum capacitor film to convert said portion into a dielectric layer of said capacitor; forming a tantalum film for resistor on the entire surface of said substrate; forming a titanium film on said tantalum resistor film; patterning said titanium film to remove a portion thereof except portions at which conductor patterns and external lead terminal connectors are formed; patterning said tantalum resistor film to form the resistor element; removing a portion of said tantalum resistor film overlying said dielectric layer; heat treating said resistor element for stabilizing the same; etching off said titanium film; forming a metal film on the entire substrate; and patterning said metal film to form terminals or conductor patterns of said resistor and capacitor elements.
Claim 5
Independent Claim
171 words
A method of forming a thin film circuit including capacitor elements and resistor elements which are formed on the same insulating substrate, comprising the steps of: forming a tantalum film for capacitor on said insulating substrate; etching said tantalum capacitor film to form a predetermined circuit pattern; anodizing a portion of said tantalum capacitor film to convert said portion into a dielectric layer of said capacitor; forming a tantalum film for resistor on the entire surface of said substrate; forming a titanium film on said tantalum resistor film; patterning said titanium film to remove a portion thereof except portions at which conductor patterns and external lead terminal connectors are formed; patterning said tantalum resistor film to form the resistor element; removing a portion of said tantalum resistor film overlying said dielectric layer; heat treating said resistor element for stabilizing the same; etching off said titanium film; forming a metal film on the entire substrate; and patterning said metal film to form terminals or conductor patterns of said resistor and capacitor elements.
Claim 6
Dependent Claim
16 words
The method according to claim 3 wherein said tantalum resistor film is a tantalum nitride film.
Claim 7
Dependent Claim
18 words
The method according to claim 3 wherein said tantalum resistor film is an oxygen doped tanalum nitride film.
Claim 8
Dependent Claim
16 words
The method according to claim 3 wherein said metal film comprises nichrome, palladium and gold layers.
Claim 9
Dependent Claim
18 words
The method according to claim 3 wherein said tantalum capacitor film has a thickness of about 5000 Å.
Claim 10
Dependent Claim
18 words
The method according to claim 3 wherein said tantalum resistor film has a thickness of about 800 Å.
Claim 11
Dependent Claim
17 words
The method according to claim 3 wherein said titanium film has a thickness of about 700 Å.
Claim 12
Dependent Claim
21 words
The method according to claim 3 wherein said resistor element is heat treated in air for 5 hours at 50° C.
Claim 13
Dependent Claim
27 words
The method according to claim 3 wherein said three layers of nichrome, palladium and gold respectively have thicknesses of about 500 Å, 2000 Å and 6000 Å.
References Cited (Backward Citations)
US3607679A
Cited
US4251326A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-01-29 | 1988-07-30 | 1989-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-29 | 1992-07-30 | 1993-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-29 | 1996-07-30 | 1997-01-29 | $7700.00 | Window Closed / Lapsed |