US3878079A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing thin tantalum films
Assignee: Siemens AG
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Filing: 1973-03-23
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Granted: 1975-04-15
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Expires: 1993-03-23
Abstract
Abstract Thin films of tantalum in the Alpha phase body-centered cubic lattice are produced by heating a substrate to a temperature above 300* C. and applying a high frequency discharge to a tantalum target member. The sputtering atmosphere is adjusted so as to contain a sputtering gas (i.e., argon) at a pressure of 1.5 X 10 3 Torr and a reactive gas (i.e., oxygen) at a partial pressure below 10 6 Torr. The resultant films have a specific resistance of about 25 Mu Omega cm and a temperature coefficient of about +1500 ppm/*C. so as to be particularly useful as initial films in thin-film electronic circuits.
Inventors
- 👤 Alois Schauer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:22
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/06; C23C14/14; C03; C03C; C03C17/00; C03C17/06; C03C17/09; C23C14/0021; C23C14/0036; C03C2217/00; C03C2217/20; C03C2217/25; C03C2217/263; C03C2218/00; C03C2218/10; C03C2218/15
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
104 words
A METHOD OF PRODUCING THIN-FILM TANTALUM IN THE A-PHASE BODY-CENTERED CUBIC LATTICE WITH A CATHODE SPUTTERING APPARATUS INCLUDING A SPUTTERING CHAMBER CONTAINING A SPUTTERING ATMOSPHERE AND A TANTALUM TARGET MEMBER, COMPRISING: HEATING A GLASS GLAZED OR CERAMIC SUBSTRATE POSITIONED WITHIN THE CHAMBER SO AS TO HAVE A SURFACE THEREOF EXPOSED TO THE TARGET MEMBER TO A TEMPERATURE ABOVE 300*C, ADJUSTING THE SPUTTERING ATMOSPHERE SO THAT IS CONTAINS A GIVEN AMOUNT OF A SPUTTERING GAS AND A MUCH SMALLER AMOUNT OF A REACTIVE GAS, APPLYING A HIGH FREQUENCY DISCHARGE TO THE TARGET MEMBER SO THAT SPUTTERING OCCURS, AND DEPOSITING RELATIVELY PURE TANTALUM IN A-PHASE BODY-
Claim 2
Independent Claim
104 words
A METHOD OF PRODUCING THIN-FILM TANTALUM IN THE A-PHASE BODY-CENTERED CUBIC LATTICE WITH A CATHODE SPUTTERING APPARATUS INCLUDING A SPUTTERING CHAMBER CONTAINING A SPUTTERING ATMOSPHERE AND A TANTALUM TARGET MEMBER, COMPRISING: HEATING A GLASS GLAZED OR CERAMIC SUBSTRATE POSITIONED WITHIN THE CHAMBER SO AS TO HAVE A SURFACE THEREOF EXPOSED TO THE TARGET MEMBER TO A TEMPERATURE ABOVE 300*C, ADJUSTING THE SPUTTERING ATMOSPHERE SO THAT IS CONTAINS A GIVEN AMOUNT OF A SPUTTERING GAS AND A MUCH SMALLER AMOUNT OF A REACTIVE GAS, APPLYING A HIGH FREQUENCY DISCHARGE TO THE TARGET MEMBER SO THAT SPUTTERING OCCURS, AND DEPOSITING RELATIVELY PURE TANTALUM IN A-PHASE BODY-
Claim 3
Dependent Claim
50 words
A method as defined in claim 1 wherein the sputtering gas is argon and is present in the sputtering atmosphere in an amount sufficient to produce a pressure of 1.5 X 10 3 Torr and the partial pressure of reactive gas in said sputtering atmosphere is below 10 6 Torr.
Claim 4
Dependent Claim
30 words
A method as defined in claim 1 wherein a pre-sputtering is effected prior to the deposition of relatively pure tantalum in Alpha -phase body centered cubic lattice on the substrate.
Claim 5
Dependent Claim
18 words
A method as defined in claim 1 wherein the exposed surface of the substrate is coated with Ta2O5.
Claim 6
Dependent Claim
22 words
A method as defined in claim 1 wherein a magnetic d.c. field is axially disposed between the target member and the substrate.
References Cited (Backward Citations)
US3258413A
Cited
US3395089A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |