US3751968A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solid state sensor
Assignee: Inficon Inc
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Filing: 1971-01-22
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Granted: 1973-08-14
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Expires: 1991-01-22
Abstract
Abstract A sensor for detecting given constituents of an atmosphere employing a solid state device formed by a glass-ceramic element having a depletion layer exposed to the atmosphere in which a given gas or vapor is to be sensed. The glass-ceramic sensor is formed with two terminals on opposite sides of the depletion layer and the terminals are connected into a circuit establishing a potential difference between the terminals across the depletion layer. By forming the glass-ceramic element of a material in which leakage currents between the terminals through the glassceramic sensing element will be produced by the presence of a given material in the atmosphere, sensing results.
Inventors
- 👤 J Loh
- 👤 C Lu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:48
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/62; G01N27/626
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
153 words
A solid state sensor for detecting the presence of given constituents of an atmosphere, said sensor comprising: a glassceramic sensing element, which consists of compositions of alkali metal ion containing metal salts selected from the classes including sodium or lithium silicate, lanthanum oxide or fluoride, and oxides or fluorides of scandium yttrium, gallium, and other rare earth metals, or aluminum, and halides; a depletion layer on a surface of said sensing element formed by the migration of thE alkali metal ions to said surface exposed to the atmosphere; a source of biasing potential; a sensing element terminal on said sensing element at a point spaced from said depletion layer and connected to said biasing potential source; means for heating said sensing element; and a depletion layer terminal spaced from said sensing element terminal and connected to said biasing potential source to form an electrical circuit through said sensing element across said depletion layer.
Claim 2
Dependent Claim
153 words
A solid state sensor for detecting the presence of given constituents of an atmosphere, said sensor comprising: a glassceramic sensing element, which consists of compositions of alkali metal ion containing metal salts selected from the classes including sodium or lithium silicate, lanthanum oxide or fluoride, and oxides or fluorides of scandium yttrium, gallium, and other rare earth metals, or aluminum, and halides; a depletion layer on a surface of said sensing element formed by the migration of thE alkali metal ions to said surface exposed to the atmosphere; a source of biasing potential; a sensing element terminal on said sensing element at a point spaced from said depletion layer and connected to said biasing potential source; means for heating said sensing element; and a depletion layer terminal spaced from said sensing element terminal and connected to said biasing potential source to form an electrical circuit through said sensing element across said depletion layer.
Claim 3
Dependent Claim
19 words
A solid state sensor as in claim 1 specifically detecting the presence of halogen containing gases in an atmosphere.
Claim 4
Dependent Claim
41 words
A solid state sensor as in claim 1 in which said sensing element terminal is formed within the interior of said sensing element; and said depletion layer and depletion layer terminal are formed on an outer surface of said sensing element.
Claim 5
Dependent Claim
23 words
A solid state sensor as in claim 3 in which said depletion layer terminal is wound over the surface of said sensing element.
Claim 6
Dependent Claim
51 words
A solid state sensor as in claim 3 in which said sensing element comprises a cylindrically shaped glass-ceramic element; said sensing element terminal comprises an elongate wire extending axially in said sensing element; and said depletion layer terminal comprises a wire coiled around the surface of said cylindrically shaped sensing element.
Claim 7
Dependent Claim
39 words
A solid state sensor as in claim 2 in which said sensing element comprises a glass-ceramic comprising a mixture of lanthanum oxide, lanthanum fluoride, and sodium silicate in a molar ratio of La2O3 . (1-2) LaF3 . (1-4.5) Na2SiO3.
Claim 8
Dependent Claim
47 words
A solid state sensor as in claim 6 in which said sensing element terminal comprises a platinum containing wire extending in the interior of said sensing element; and said depletion layer terminal comprises a coil of platinum containing wire coiled around the surface of said sensing element.
Claim 9
Dependent Claim
21 words
A solid state sensor as in claim 4 in which said depletion layer terminal is connected to a heater power supply.
Claim 10
Dependent Claim
107 words
A solid state sensor as in claim 1 in which said glass-ceramic sensing element comprises a mixture of lanthanum oxide, lanthanum fluoride, and soidum silicate formed into a cylindrical shape; said sensing element terminal comprises a platinum wire extending along the longitudinal axis of said cylindrically shaped sensing element; said depletion layer terminal comprises a coil of platinum wire wound over the surface of said cylindrically shaped sensing element; said biasing potential source having a negative connection to said sensing element terminal and a positive connection to said depletion layer terminal; and a heater power supply, said coil coupled in a circuit to said heater power supply.
Claim 11
Independent Claim
81 words
A method of forming a gas or vapor sensing element comprising the steps of coating a conductor with a slurry containing ion containing alkali metal salts; drying the slurry; and arranging a conductor in contact with the surface of the dried slurry coating the conductor; heating said element and establishing a biasing potential difference between the coated conductor and the surface contacting conductor to form a depletion layer by causing a migration of said metal ions toward the negatively connected conductor.
Claim 12
Independent Claim
81 words
A method of forming a gas or vapor sensing element comprising the steps of coating a conductor with a slurry containing ion containing alkali metal salts; drying the slurry; and arranging a conductor in contact with the surface of the dried slurry coating the conductor; heating said element and establishing a biasing potential difference between the coated conductor and the surface contacting conductor to form a depletion layer by causing a migration of said metal ions toward the negatively connected conductor.
Claim 13
Dependent Claim
30 words
A method as in claim 10 comprising the steps of forming the slurry with which the conductor is coated of a mixture of sodium silicate, lanthanum fluoride, and lanthanum oxide.
Claim 14
Dependent Claim
16 words
A method as in claim 11 in which said conductors are formed of platinum containing wire.
Claim 15
Dependent Claim
24 words
A method as in claim 10 in which said surface contact conductor is formed of a coil of wire wound around the slurry coating.
Claim 16
Dependent Claim
19 words
A method as in claim 13 in which said coil of wire is connected to a heater power supply.
Claim 17
Independent Claim
139 words
A method of sensing the presence of a gas or vapor in an atmosphere, said method comprising the steps of: positioning a solid state element consisting of alkali metal ion containing compositions of metal salts selected from the clAsses including sodium or lithium silicate, lanthanum oxide or fluoride, and oxides or fluorides of scandium, yttrium, gallium, and other rare earth metals, or aluminum, and halides in the atmosphere in which the gas or vapor is to be sensed; establishing a voltage difference across said solid state element to cause migration of the alkali metal ions to form a depletion layer on a portion of the surface of the solid state element exposed to the atmosphere; heating said solid state element; establishing a circuit between opposite sides of the depletion layer; and sensing the flow of current through said circuit.
Claim 18
Independent Claim
139 words
A method of sensing the presence of a gas or vapor in an atmosphere, said method comprising the steps of: positioning a solid state element consisting of alkali metal ion containing compositions of metal salts selected from the clAsses including sodium or lithium silicate, lanthanum oxide or fluoride, and oxides or fluorides of scandium, yttrium, gallium, and other rare earth metals, or aluminum, and halides in the atmosphere in which the gas or vapor is to be sensed; establishing a voltage difference across said solid state element to cause migration of the alkali metal ions to form a depletion layer on a portion of the surface of the solid state element exposed to the atmosphere; heating said solid state element; establishing a circuit between opposite sides of the depletion layer; and sensing the flow of current through said circuit.
Claim 19
Dependent Claim
27 words
A method as in claim 15 comprising the step of heating the atmosphere adjacent the depletion layer to ionize the gas or vapor adjacent the depletion layer.
Claim 20
Dependent Claim
34 words
A method as in claim 15 for specifically sensing halogen containing gases or vapors comprising the step of forming the solid state element of a mixture of sodium silicate, lanthanum fluoride, and lanthanum oxide.
Claim 21
Dependent Claim
27 words
A method as in claim 15 comprising the step of forming platinum containing terminals on the solid state element between which terminals the voltage difference is established.
Claim 22
Dependent Claim
34 words
A method as in claim 16 in which said heating step is performed by forming a coil of wire about the solid state element, and establishing a current flow through the coil of wire.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-13 | 1977-02-12 | 1977-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-13 | 1981-02-12 | 1981-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-13 | 1985-02-12 | 1985-08-14 | $7700.00 | Window Closed / Lapsed |