US4627902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing a resistance element for a resistance thermometer
Assignee: Emerson Process Management Ltd
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Filing: 1984-04-05
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Granted: 1986-12-09
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Expires: 2004-04-05
Abstract
Abstract A resistance thermometer element having a thin layer of platinum metal on an insulating substrate is formed by magnetron sputtering in a gaseous atmosphere containing at least 10% by volume of oxygen. Any balance gas has less than 10% by volume of argon, krypton and xenon. The atmosphere may have up to 100% oxygen with any balance gas being inert to platinum. Air can be used. A planar magnetron may be used.
Inventors
- 👤 James S. Johnston
- 👤 Leslie Holland
- 👤 Christopher R. Wright
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:16
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/22; C; C23; C23C; C23C14/00; C23C14/0021; C23C14/0036; G; G01; G01K; G01K7/00; G01K7/16; G01K7/18; H01C17/00; H01C17/06; H01C17/075; H01C17/12
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
79 words
A method of producing a thin film platinum resistance thermometer element having a TCR of about 3.85×10 -3 ppm/°C. which comprises magnetron sputtering a platinum film onto an insulating substrate in a sputtering atmosphere consisting of at least about 20% by volume of oxygen, with the balance gas consisting primarily of nitrogen, and heat treating the film after sputtering to remove any entrapped oxygen from the film and reduce or dissociate platinum oxide in the film to platinum metal.
Claim 2
Independent Claim
79 words
A method of producing a thin film platinum resistance thermometer element having a TCR of about 3.85×10 -3 ppm/°C. which comprises magnetron sputtering a platinum film onto an insulating substrate in a sputtering atmosphere consisting of at least about 20% by volume of oxygen, with the balance gas consisting primarily of nitrogen, and heat treating the film after sputtering to remove any entrapped oxygen from the film and reduce or dissociate platinum oxide in the film to platinum metal.
Claim 3
Dependent Claim
29 words
A method as claimed in claim 1 and including heat treating the thin platinum layer after sputtering at between 700° C. and 1200° C. for at least 5 hours.
Claim 4
Dependent Claim
21 words
A method as claimed in claim 2 wherein said heat treating is carried out for at least 5 to 10 hours.
Claim 5
Dependent Claim
18 words
A method as claimed in claim 3 wherein said heat treating is carried out for about 20 hours.
Claim 6
Dependent Claim
30 words
A method as claimed in claim 1 and including the further step, after said heat treating, of scribing the platinum layer with a laser to form an extended path thereof.
Claim 7
Dependent Claim
36 words
A method as claimed in claim 5 and including the futher step, after said laser scribing, of further heat treating the scribed platinum layer at between 700° C. and 1200° C. for at least 1 hour.
Claim 8
Dependent Claim
19 words
A method as claimed in claim 1 wherein said gaseous atmosphere is at least 50% by volume of oxygen.
Claim 9
Dependent Claim
18 words
A method as claimed in claim 1 wherein said gaseous atmosphere is about 20% by volume of oxygen.
Claim 10
Dependent Claim
13 words
A method as claimed in claim 8 wherein said gaseous atmosphere is air.
Claim 11
Dependent Claim
16 words
A method as claimed in claim 1 wherein the sputtering target used is 99.99% pure platinum.
Claim 12
Dependent Claim
23 words
A method as claimed in claim 1 wherein the pressure of said gaseous atmosphere is between 10 -3 Torr and 10 -2 Torr.
Claim 13
Dependent Claim
19 words
A method as claimed in claim 11 wherein the pressure is between 4×10 -3 Torr and 6×10 -3 Torr.
Claim 14
Dependent Claim
19 words
A method as claimed in claim 11 wherein the pressure is between 6×10 -3 Torr and 9×10 -3 Torr.
Claim 15
Dependent Claim
23 words
A method as claimed in claim 1 wherein the pressure of said gaseous atmosphere is between 10 -2 Torr and 10 -1 Torr.
Claim 16
Dependent Claim
11 words
A method as claimed in claim 1 using a planar magnetron.
Claim 17
Dependent Claim
27 words
A method as claimed in claim 15 wherein the magnetron is arranged to confine the electrons to drift in a closed path perpendicular to an electric field.
Claim 18
Dependent Claim
14 words
A method as claimed in claim 16 wherein the closed path is generally circular.
Claim 19
Independent Claim
64 words
A method of producing a thin film platinum resistance thermometer element having a TCR of about 3.85×10 -3 ppm/°C. which comprises magnetron sputtering a platinum film onto an insulating substrate in a substantially pure oxygen sputtering atmosphere, and heat treating the film after sputtering to remove any entrapped oxygen from the film and reduce or dissociate platinum oxide in the film to platinum metal.
Claim 20
Independent Claim
64 words
A method of producing a thin film platinum resistance thermometer element having a TCR of about 3.85×10 -3 ppm/°C. which comprises magnetron sputtering a platinum film onto an insulating substrate in a substantially pure oxygen sputtering atmosphere, and heat treating the film after sputtering to remove any entrapped oxygen from the film and reduce or dissociate platinum oxide in the film to platinum metal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-08 | 1990-06-09 | 1990-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-08 | 1994-06-09 | 1994-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-08 | 1998-06-09 | 1998-12-09 | $7700.00 | Window Closed / Lapsed |