US5095401A
Expired / Lapsed
US
⏱️ 0.0 years remaining
SOI diaphragm sensor
Assignee: Kopin Corp
•
Filing: 1990-05-21
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Granted: 1992-03-10
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Expires: 2010-05-21
Abstract
Abstract The present invention relates to the fabrication of diaphragm pressure sensors utilizing silicon-on-insulator technology where recrystallized silicon forms a diaphragm which incorporates electronic devices used in monitoring pressure. The diaphragm is alternatively comprised of a silicon nitride having the necessary mechanical properties with a recrystallized silicon layer positioned thereon to provide sensor electronics.
Inventors
- 👤 Paul M. Zavracky
- 👤 Richard H. Morrison, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:45
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/0041; G01L9/0051; G01L9/0052; G01L9/0055; G01L9/0042; G01L9/0072; G01L9/0073; G01P; G01P15/00; G01P15/02; G01P15/08; G01P15/0802; G01P15/12; G01P15/123; G01P2015/0805; G01P2015/0822; G01P2015/0825; G01P2015/0828
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
52 words
A self-calibrated sensor comprising: a substrate of semiconductor material; a layer of sacrificial material formed on the substrate; a sensor structure formed with a layer of epitaxial semiconductor material positioned over the layer of sacrificial material; and a calibration circuit formed in the layer of epitaxial semiconductor material to calibrate the sensor.
Claim 2
Dependent Claim
52 words
A self-calibrated sensor comprising: a substrate of semiconductor material; a layer of sacrificial material formed on the substrate; a sensor structure formed with a layer of epitaxial semiconductor material positioned over the layer of sacrificial material; and a calibration circuit formed in the layer of epitaxial semiconductor material to calibrate the sensor.
Claim 3
Dependent Claim
26 words
The sensor of claim 1 wherein said calibration circuit comprises a processing circuit that interacts with a memory which stores calibration information to calibrate the sensor.
Claim 4
Dependent Claim
21 words
The sensor of claim 2 wherein the memory is a programmable memory such that stored calibration information can be selectively altered.
Claim 5
Dependent Claim
13 words
The sensor of claim 2 wherein the sensor structure is a pressure sensor.
Claim 6
Dependent Claim
19 words
The sensor of claim 4 wherein the calibration information comprises information about a zero calibration point and a span.
Claim 7
Dependent Claim
12 words
The sensor of claim 1 wherein the substrate is comprised of silicon.
Claim 8
Dependent Claim
15 words
The sensor of claim 1 wherein the electrically insulating layer is comprised of silicon oxide.
Claim 9
Dependent Claim
67 words
A microsensor comprising: a substrate of semiconductor material; a layer of sacrificial material deposited on the substrate; a sensor structure formed in a layer of epitaxial semiconductor material positioned over the layer of sacrificial material; and a monitoring circuit formed on the layer of epitaxial semiconductor material that determines whether an additional circuit in the sensor is shorted or whether another circuit in the sensor is open.
Claim 10
Dependent Claim
67 words
A microsensor comprising: a substrate of semiconductor material; a layer of sacrificial material deposited on the substrate; a sensor structure formed in a layer of epitaxial semiconductor material positioned over the layer of sacrificial material; and a monitoring circuit formed on the layer of epitaxial semiconductor material that determines whether an additional circuit in the sensor is shorted or whether another circuit in the sensor is open.
Claim 11
Dependent Claim
14 words
The microsensor of claim 8 wherein the sensor structure is a pressure sensing structure.
Claim 12
Dependent Claim
12 words
The microsensor of claim 8 wherein the substrate is comprised of silicon.
Claim 13
Dependent Claim
14 words
The microsensor of claim 8 wherein the sacrificial layer is comprised of silicon oxide.
Claim 14
Dependent Claim
47 words
A microsensor comprising: a substrate of semiconductor material; a layer of sacrificial material formed on the substrate; a sensor structure formed in the layer of sacrificial material; and a calibration circuit formed in the layer of epitaxial silicon that compensates for a non-linear characteristic of the sensor.
Claim 15
Dependent Claim
47 words
A microsensor comprising: a substrate of semiconductor material; a layer of sacrificial material formed on the substrate; a sensor structure formed in the layer of sacrificial material; and a calibration circuit formed in the layer of epitaxial silicon that compensates for a non-linear characteristic of the sensor.
Claim 16
Dependent Claim
18 words
The microsensor of claim 12 wherein the calibration circuit compensates for non-linear characteristic produced by an environmental condition.
Claim 17
Dependent Claim
11 words
The microsensor of claim 13 wherein the environmental condition includes temperature.
Claim 18
Dependent Claim
22 words
The microsensor of claim 12 wherein the sensor generates an electrical signal correlated with a pressure of a fluid contacting the sensor.
Claim 19
Dependent Claim
12 words
The microsensor of claim 12 wherein the substrate is comprised of silicon.
Claim 20
Dependent Claim
15 words
The microsensor of claim 12 wherein the electrically insulating layer is comprised of silicon oxide.
Claim 21
Dependent Claim
63 words
An integrated circuit comprising: a substrate of silicon; a layer of electrically insulating material; a plurality of redundant sensor structures formed out of a layer of silicon nitride deposited on the layer of electrically insulating material such that if one sensor structure fails, another redundant sensor structure replaces the failed sensor; and an electrical circuit formed on the layer of epitaxial silicon nitride.
Claim 22
Dependent Claim
63 words
An integrated circuit comprising: a substrate of silicon; a layer of electrically insulating material; a plurality of redundant sensor structures formed out of a layer of silicon nitride deposited on the layer of electrically insulating material such that if one sensor structure fails, another redundant sensor structure replaces the failed sensor; and an electrical circuit formed on the layer of epitaxial silicon nitride.
Claim 23
Dependent Claim
23 words
The integrated circuit of claim 18 wherein the microsensor generates an electrical signal correlated with a pressure of a fluid contacting the sensor.
Claim 24
Dependent Claim
17 words
The integrated circuit of claim 18 wherein the sensor structure comprises a diaphragm stretched across a cavity.
Claim 25
Independent Claim
97 words
A method of forming a semiconductor diaphragm pressure sensor comprising: forming an electrically insulating layer portion on a semiconductor substrate; forming a polycrystalline semiconductor layer over the substrate that encloses the insulating layer portion between the semiconductor and the substrate; recrystallizing the polycrystalline layer to form a substantially single crystal flexible member; integrating an electronic circuit into the single crystal member; opening a portion of the single crystal member to expose a surface portion of the insulating portion; removing the enclosed insulating portion through the opened portion; and sealing the opened portion of the single crystal member.
Claim 26
Independent Claim
97 words
A method of forming a semiconductor diaphragm pressure sensor comprising: forming an electrically insulating layer portion on a semiconductor substrate; forming a polycrystalline semiconductor layer over the substrate that encloses the insulating layer portion between the semiconductor and the substrate; recrystallizing the polycrystalline layer to form a substantially single crystal flexible member; integrating an electronic circuit into the single crystal member; opening a portion of the single crystal member to expose a surface portion of the insulating portion; removing the enclosed insulating portion through the opened portion; and sealing the opened portion of the single crystal member.
Claim 27
Dependent Claim
35 words
The method of claim 21 further comprising forming a transducer in the single crystal layer such that a displacement of the single crystal layer relative to the substrate generates an electrical signal from the transducer.
Claim 28
Dependent Claim
13 words
The method of claim 21 wherein said semiconductor layer is comprised of silicon.
Claim 29
Dependent Claim
19 words
The method of claim 21 wherein said opening is formed with an anisotropic etch of the single crystal member.
Claim 30
Dependent Claim
15 words
The method of claim 21 wherein the insulating layer portion is comprised of an oxide.
Claim 31
Independent Claim
103 words
A method of forming semiconductor diaphragm pressure sensor comprising: forming an insulating layer portion on a semiconductor substrate; forming a silicon nitride layer over the substrate such that the insulating portion is enclosed between the nitride layer and the substrate; forming a polycrystalline silicon layer over the silicon nitride layer; recrystallizing the polycrystalline layer to form a substantially single crystal silicon layer; integrating an electronic circuit into the crystal silicon layer; opening a portion of the silicon nitride layer to expose a surface portion of the insulating portion; and removing the insulation portion through the opened portion to form a silicon nitride diaphragm.
Claim 32
Independent Claim
103 words
A method of forming semiconductor diaphragm pressure sensor comprising: forming an insulating layer portion on a semiconductor substrate; forming a silicon nitride layer over the substrate such that the insulating portion is enclosed between the nitride layer and the substrate; forming a polycrystalline silicon layer over the silicon nitride layer; recrystallizing the polycrystalline layer to form a substantially single crystal silicon layer; integrating an electronic circuit into the crystal silicon layer; opening a portion of the silicon nitride layer to expose a surface portion of the insulating portion; and removing the insulation portion through the opened portion to form a silicon nitride diaphragm.
Claim 33
Dependent Claim
14 words
The method of claim 26 further comprising the step of sealing the opened portion.
Claim 34
Dependent Claim
34 words
The method of claim 27 further comprising forming a transducer in the single crystal layer such that a displacement of the nitride layer relative to the substrate generates an electrical signal from the transducer.
Claim 35
Dependent Claim
20 words
The method of claim 28 further comprising forming a second insulating layer between the nitride layer and the silicon layer.
Claim 36
Dependent Claim
90 words
A differential semiconductor pressure sensor comprising: a substrate of polysilicon; a first layer of electrically insulating, material deposited on the substrate; an epitaxial silicon diaphragm formed on top of the first layer of electrically insulating material; a second layer of electrically insulating material deposited over the epitaxial silicon diaphragm; a polysilicon nitride film to cap the sensor; a lower cavity formed in the substrate below the diaphragm and first electrically insulating layer; and an upper cavity formed in the polysilicon nitride film above the diaphragm and second electrically insulating layer.
Claim 37
Dependent Claim
90 words
A differential semiconductor pressure sensor comprising: a substrate of polysilicon; a first layer of electrically insulating, material deposited on the substrate; an epitaxial silicon diaphragm formed on top of the first layer of electrically insulating material; a second layer of electrically insulating material deposited over the epitaxial silicon diaphragm; a polysilicon nitride film to cap the sensor; a lower cavity formed in the substrate below the diaphragm and first electrically insulating layer; and an upper cavity formed in the polysilicon nitride film above the diaphragm and second electrically insulating layer.
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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) | 1995-03-10 | 1995-09-09 | 1996-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-10 | 1999-09-09 | 2000-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-10 | 2003-09-09 | 2004-03-10 | $7700.00 | Window Closed / Lapsed |