Patent US4323875A successfully refreshed from Google Patents.
US4323875A
Expired / Lapsed
US
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Method of making temperature sensitive device and device made thereby
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1981-01-21
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Granted: 1982-04-06
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Expires: 2001-01-21
Abstract
Abstract A method of making a thin nickel film temperature sensitive device with a relatively high positive temperature coefficient of resistance utilizing a film of nickel deposited from a bulk nickel source onto an electrically insulating substrate, and device made thereby including the step of heat treating a resistor element having a thin film of nickel deposited on an electrically insulating substrate by heating in a reducing atmosphere to a peak temperature of at least 550° C., over a heating cycle of at least about 20 minutes. The nickel film of the heat treated resistor element has a selected temperature coefficient of resistance which is at least 60% of the value of the coefficient for the bulk nickel and a sheet resistance of at least one ohm per square which properties are determined by the heat treating temperature and cycle time, and the thickness of the nickel film. The resistor element can be made by vacuum depositing the nickel film to the desired thickness onto the insulating substrate, and affixing terminations to the ends of the resistor element and applying a protective outer coating to the nickel film after the heat treating of the element.
Inventors
- 👤 Joseph A. Tentarelli
- 👤 Richard L. Wahlers
- 👤 John G. Woods
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:24
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/075; H01C17/08; H01C17/30; H01C7/00; H01C7/02; H01C7/021; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49085
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
144 words
A method of making a thin nickel film temperature sensitive device with a relatively high positive temperature coefficient of resistance utilizing a film of nickel deposited from a bulk nickel source onto an electrically insulating substrate, including the step of heat treating a resistor element having a thin film of nickel deposited on an electrically insulating substrate by heating in a reducing atmosphere to a peak temperature of at least 550° C., over a heating cycle of at least about 20 minutes, whereby the nickel film of the heat treated resistor element has a selected temperature coefficient of resistance which is at least 60% of the value of the coefficient for the bulk nickel and a sheet resistance of at least one ohm per square which properties are determined by the heat treating temperature and cycle time, and the thickness of the nickel film.
Claim 2
Independent Claim
144 words
A method of making a thin nickel film temperature sensitive device with a relatively high positive temperature coefficient of resistance utilizing a film of nickel deposited from a bulk nickel source onto an electrically insulating substrate, including the step of heat treating a resistor element having a thin film of nickel deposited on an electrically insulating substrate by heating in a reducing atmosphere to a peak temperature of at least 550° C., over a heating cycle of at least about 20 minutes, whereby the nickel film of the heat treated resistor element has a selected temperature coefficient of resistance which is at least 60% of the value of the coefficient for the bulk nickel and a sheet resistance of at least one ohm per square which properties are determined by the heat treating temperature and cycle time, and the thickness of the nickel film.
Claim 3
Dependent Claim
21 words
The method of making a temperature sensitive device in accordance with claim 1 in which the heating atmosphere is slightly reducing.
Claim 4
Dependent Claim
25 words
The method of making a temperature sensitive device in accordance with claim 1 in which the heating atmosphere is a mixture of nitrogen and hydrogen.
Claim 5
Dependent Claim
32 words
The method of making a temperature sensitive device in accordance with claim 3 in which the volume percent of the hydrogen of the heating atmosphere is less than that of the nitrogen.
Claim 6
Dependent Claim
30 words
The method of making a temperature sensitive device in accordance with claim 4 in which the volume percent of the hydrogen of the heating atmosphere is not greater than 15%.
Claim 7
Dependent Claim
30 words
The method of making a temperature sensitive device in accordance with claim 5 in which the volume percent of the hydrogen of the heating atmosphere is not greater than 5%.
Claim 8
Dependent Claim
30 words
The method of making a temperature sensitive device in accordance with claim 6 in which the volume percent of the hydrogen of the heating atmosphere is not greater than 1%.
Claim 9
Dependent Claim
34 words
The method of making a temperature sensitive device in accordance with claim 1 in which the resistor element is heat treated over a heating cycle of between about one-half hour to about four hours.
Claim 10
Dependent Claim
34 words
The method of making a temperature sensitive device in accordance with claim 1 in which the resistor element is heat treated to a peak temperature of between about 600° C. and about 950° C.
Claim 11
Dependent Claim
45 words
The method of making a temperature sensitive device in accordance with claim 9 in which the resistor element is heat treated to a peak temperature of between about 750° C. and about 850° C., and the heating cycle is between one-half hour and two hours.
Claim 12
Dependent Claim
29 words
The method of making a temperature sensitive device in accordance with claim 10 in which the resistor element is heat treated to a peak temperature of about 800° C.
Claim 13
Dependent Claim
49 words
The method of making a temperature sensitive device in accordance with claim 3 in which the resistor element is heat treated to a peak temperature of at least about 600° C. for about one and one-half hours in an atmosphere in which the nitrogen is about 95 volume percent.
Claim 14
Dependent Claim
92 words
The method of making a temperature sensitive device in accordance with claim 3 in which the resistor element is heat treated by heating in a furnace to a peak temperature of between 550° C. and 700° C. over a period of about 3 hours in an atmosphere in which the nitrogen is about 99 volume percent and the hydrogen is about 1 volume percent, the resistor element is held at the peak temperature for about one-quarter hour, and then allowed to cool with the furnace to a temperature of about 25° C.
Claim 15
Dependent Claim
55 words
The method of making a temperature sensitive device in accordance with claim 1, 5, 6, 7, 9, 10 or 12 which includes an auxiliary heat treating step preceding the reducing heat treating step of heating the resistor element in air at a temperature of about 350° C. for a cycle time of about one hour.
Claim 16
Dependent Claim
87 words
The method of making a temperature sensitive device in accordance with claim 1, 5, 6, 7, 9 or 10 which includes an auxiliary heat treating step preceding the reducing heat treating step of heating the resistor element in air at a temperature of about 350° C. for a cycle time of about one hour, and a stabilizing heat treating step following the reducing heat treating step of heating the resistor element in air at a temperature of about 250° C. for a period of about one hour.
Claim 17
Dependent Claim
42 words
The method of making a temperature sensitive device in accordance with claim 1, 5, 6, 7, 9 or 10 in which the relatively high temperature coefficient of resistance of the device is at least 80% of the value for the bulk nickel.
Claim 18
Dependent Claim
42 words
The method of making a temperature sensitive device in accordance with claim 1, 5, 6, 7, 9 or 10 in which the relatively high temperature coefficient of resistance of the device is at least 90% of the value for the bulk nickel.
Claim 19
Dependent Claim
42 words
The method of making a temperature sensitive device in accordance with claim 1, 5, 6, 7, 9 or 10 in which the relatively high temperature coefficient of resistance of the device is at least 95% of the value for the bulk nickel.
Claim 20
Dependent Claim
69 words
The method of making a temperature sensitive device in accordance with claim 1, 5, 6, 7, 9 or 10 which includes the steps of preparing the resistor element by vacuum depositing the nickel film to the desired thickness onto the insulating substrate, and affixing terminations to the ends of the resistor element and applying a protective outer coating to the nickel film after the heat treating of the element.
Claim 21
Dependent Claim
133 words
A thin film temperature sensitive device with a relatively high positive temperature coefficient of resistance utilizing a film of nickel deposited from a bulk nickel source onto an electrically insulating substrate, made by heat treating a resistor element having a film of nickel deposited on an electrically insulating substrate by heating in a reducing atmosphere to a peak temperature of at least 550° C., over a heating cycle of at least about 20 minutes, whereby the nickel film of the heat treated resistor element has a selected temperature coefficient of resistance which is at least 60% of the value of the coefficient for the bulk nickel and a sheet resistance of at least one ohm per square determined by the heat treating temperature and cycle time, and the thickness of the nickel film.
Claim 22
Dependent Claim
133 words
A thin film temperature sensitive device with a relatively high positive temperature coefficient of resistance utilizing a film of nickel deposited from a bulk nickel source onto an electrically insulating substrate, made by heat treating a resistor element having a film of nickel deposited on an electrically insulating substrate by heating in a reducing atmosphere to a peak temperature of at least 550° C., over a heating cycle of at least about 20 minutes, whereby the nickel film of the heat treated resistor element has a selected temperature coefficient of resistance which is at least 60% of the value of the coefficient for the bulk nickel and a sheet resistance of at least one ohm per square determined by the heat treating temperature and cycle time, and the thickness of the nickel film.
Claim 23
Dependent Claim
18 words
The temperature sensitive device made in accordance with claim 20 in which the heating atmosphere is slightly reducing.
Claim 24
Dependent Claim
22 words
The temperature sensitive device made in accordance with claim 20 in which the heating atmosphere is a mixture of nitrogen and hydrogen.
Claim 25
Dependent Claim
29 words
The temperature sensitive device made in accordance with claim 22 in which the volume percent of the hydrogen of the heating atmosphere is less than that of the nitrogen.
Claim 26
Dependent Claim
27 words
The temperature sensitive device made in accordance with claim 23 in which the volume percent of the hydrogen of the heating atmosphere is not greater than 15%.
Claim 27
Dependent Claim
27 words
The temperature sensitive device made in accordance with claim 24 in which the volume percent of the hydrogen of the heating atmosphere is not greater than 5%.
Claim 28
Dependent Claim
27 words
The temperature sensitive device made in accordance with claim 25 in which the volume percent of the hydrogen of the heating atmosphere is not greater than 1%.
Claim 29
Dependent Claim
31 words
The temperature sensitive device made in accordance with claim 20 in which the resistor element is heat treated over a heating cycle of between about one-half hour to about four hours.
Claim 30
Dependent Claim
31 words
The temperature sensitive device made in accordance with claim 20 in which the resistor element is heat treated to a peak temperature of between about 600° C. and about 950° C.
Claim 31
Dependent Claim
42 words
The temperature sensitive device made in accordance with claim 28 in which the resistor element is heat treated to a peak temperature of between about 750° C. and about 850° C., and the heating cycle is between one-half hour and two hours.
Claim 32
Dependent Claim
26 words
The temperature sensitive device made in accordance with claim 29 in which the resistor element is heat treated to a peak temperature of about 800° C.
Claim 33
Dependent Claim
46 words
The temperature sensitive device made in accordance with claim 22 in which the resistor element is heat treated to a peak temperature of at least about 600° C. for about one and one-half hours in an atmosphere in which the nitrogen is about 95 volume percent.
Claim 34
Dependent Claim
89 words
The temperature sensitive device made in accordance with claim 22 in which the resistor element is heat treated by heating in a furnace to a peak temperature of between 550° C. and 700° C. over a period of about 3 hours in an atmosphere in which the nitrogen is about 99 volume percent and the hydrogen is about 1 volume percent, the resistor element is held at the peak temperature for about one-quarter hour, and then allowed to cool with the furnace to a temperature of about 25° C.
Claim 35
Dependent Claim
52 words
The temperature sensitive device made in accordance with claim 20, 24, 25, 26, 28, 30 or 31 which includes an auxiliary heat treating step preceding the reducing heat treating step of heating the resistor element in air at a temperature of about 350° C. for a cycle time of about one hour.
Claim 36
Dependent Claim
84 words
The temperature sensitive device made in accordance with claim 20, 24, 25, 26, 28 or 29 which includes an auxiliary heat treating step preceding the reducing heat treating step of heating the resistor element in air at a temperature of about 350° C. for a cycle time of about one hour, and a stabilizing heat treating step following the reducing heat treating step of heating the resistor element in air at a temperature of about 250° C. for a period of about one hour.
Claim 37
Dependent Claim
39 words
The temperature sensitive device made in accordance with claim 20, 24, 25, 26, 28 or 29 in which the relatively high temperature coefficient of resistance of the device is at least 80% of the value for the bulk nickel.
Claim 38
Dependent Claim
39 words
The temperature sensitive device made in accordance with claim 20, 24, 25, 26, 28 or 29 in which the relatively high temperature coefficient of resistance of the device is at least 90% of the value for the bulk nickel.
Claim 39
Dependent Claim
39 words
The temperature sensitive device made in accordance with claim 20, 24, 25, 26, 28 or 29 in which the relatively high temperature coefficient of resistance of the device is at least 95% of the value for the bulk nickel.
Claim 40
Dependent Claim
66 words
The temperature sensitive device made in accordance with claim 20, 24, 25, 26, 28 or 29 which includes the steps of preparing the resistor element by vacuum depositing the metal film into the insulating substrate to the desired thickness, and affixing terminations to the ends of the resistor element and applying a protective outer coating to the nickel film after the heat treating of the element.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-04-05 | 1985-10-05 | 1986-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-04-05 | 1989-10-05 | 1990-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-04-05 | 1993-10-05 | 1994-04-06 | $7700.00 | Window Closed / Lapsed |