Electrostatic pressure transducer and a method thereof

• US 6,688,179 B2
• Filed: 10/24/2002
• Issued: 02/10/2004
• Est. Priority Date: 10/26/2001
• Status: Expired due to Fees

• Current Assignee: Nth Tech Corporation
• Original Assignee: Nth Tech Corporation
• Inventors: Potter, Michael D., Martens, Alexander E.
• Primary Examiner(s): Lefkowitz, Edward
• Assistant Examiner(s): ALLEN, ANDRE J
• Application Number:
  US10/280,264
• Publication Number:
  US 20030079548A1
• Time in Patent Office: 474 Days
• Field of Search: 737/00, 735/143.2, 361/280, 257/252, 257/248
• US Class Current: 73/700
• CPC Class Codes: B81B 2201/0257 Microphones or microspeakers
• CPC Class Codes: B81C 1/00158 Diaphragms, membranes manufacture process for semi-permeable inorganic membranes B01D67/0039
• CPC Class Codes: B81C 2201/0109 Sacrificial layers not provided for in B81C2201/0107 - B81C2201/0108
• CPC Class Codes: G01L 9/0073 using a semiconductive diaphragm
• CPC Class Codes: G01L 9/0075 using a ceramic diaphragm, e.g. alumina, fused quartz, glass

Abstract

A pressure transducer system includes a housing with a chamber, a member with a stored electrical charge, and a pair of electrodes that are at least partially in alignment with each other. At least a portion of the chamber is at a reference pressure. The member is connected to the housing and extends across at least a portion of the chamber. Each of the pair of electrodes is connected to the housing and is spaced from and on substantially opposing sides of the member. The member is movable with respect to the pair of electrodes or one of the pair of electrodes is movable with respect to the member in response to a monitored pressure.

Claims

1. A pressure transducer system comprising:

a housing with a chamber, at least a portion of the chamber is sealed at a reference pressure;

a non-conducting member with a stored electrical charge, the non-conducting member connected to the housing and extending at least partially across the chamber; and

a pair of electrodes that are at least partially in alignment with each other, with each of the pair of electrodes connected to the housing and spaced from and on substantially opposing sides of the non-conducting member, wherein the non-conducting member is movable with respect to the pair of electrodes or one of the electrodes in the pair of electrodes is movable with respect to the non-conducting member in response to a monitored pressure.

2. The system as set forth in claim 1 wherein the member divides the chamber into a first compartment and a second compartment, the first compartment or the second compartment is sealed at the reference pressure.

3. The system as set forth in claim 2 further comprising at least one opening extending into the first compartment or the second compartment to the first compartment or the second compartment to the pressure to be measured, the other one of the first compartment or the second compartment is sealed at the reference pressure.

4. The system as set forth in claim 2 wherein the first compartment or the second compartment is filled with at least fluid at the reference pressure and the other one of the first compartment or the second compartment is filled with at least one material.

5. The system as set forth in claim 1 further comprising a pressure monitoring device coupled to the pair of electrodes, the pressure monitoring device determining the pressure in response to the movement of the member with respect to the pair of electrodes or the one of the electrodes in the pair of electrodes with respect to the member.

6. The system as set forth in claim 1 wherein the at least a portion of the chamber is vacuum sealed and the reference pressure is zero.

7. The system as set forth in claim 1 wherein the member comprises two or more dielectric layers.

8. The system as set forth in claim 1 wherein the member comprises a single dielectric layer.

9. The system as set forth in claim 1 wherein the member is made from one or more materials selected from a group consisting of silicon oxide, silicon dioxide, silicon nitride, aluminum oxide, tantalum oxide, tantalum pentoxide, titanium oxide, titanium dioxide, barium strontium titanium oxide.

10. A method for making a pressure transducer system, the method comprising:

providing a housing with a chamber, at least a portion of the chamber is sealed at a reference pressure;

providing a non-conducting member with a stored electrical charge, the non-conducting member connected to the housing and extending at least partially across the chamber; and

providing a pair of electrodes that are at least partially in alignment with each other, with each of the pair of electrodes connected to the housing and spaced from and on substantially opposing sides of the non-conducting member, wherein the non-conducting member is movable with respect to the pair of electrodes or one of the electrodes in the pair of electrodes is movable with respect to the non-conducting member in response to a monitored pressure.

11. The method as set forth in claim 10 wherein the provided member divides the chamber into a first compartment and a second compartment, one of the first and second compartments is sealed at the reference pressure.

12. The method as set forth in claim 11 further comprising providing at least one opening extending into the first compartment or the second compartment to expose the first compartment or the second compartment to the monitored pressure, the other one of the first compartment or the second compartment is sealed at the reference pressure.

13. The method as set forth in claim 11 further comprising filling the first compartment or the second compartment with at least fluid at the reference pressure and filling the other one of the first compartment or the second compartment with at least one material.

14. The method as set forth in claim 10 further comprising providing a pressure monitoring device coupled to the pair of electrodes, the pressure monitoring device determining the pressure in response to the movement of the member with respect to the pair of electrodes or the one of the electrodes in the pair of electrodes with respect to the member.

15. The method as set forth in claim 10 wherein the at least a portion of the chamber is vacuum sealed and the reference pressure is zero.

16. The method as set forth in claim 10 wherein the member comprises two or more dielectric layers.

17. The method as set forth in claim 10 wherein the member comprises a single dielectric layer.

18. The method as set forth in claim 10 wherein the member is made from one or more materials selected from a group consisting of silicon oxide, silicon dioxide, silicon nitride, aluminum oxide, tantalum oxide, tantalum pentoxide, titanium oxide, titanium dioxide, barium strontium titanium oxide.

19. A method for measuring pressure, the method comprising:

exposing a non-conducting member with a stored electrical charge or one of a pair of electrodes to a monitored pressure, the member is connected to a housing with a chamber, at least a portion of the chamber is sealed at a reference pressure, the non-conducting member extends across at least a portion of the chamber, each of a pair of electrodes is connected to the housing and is spaced from and on substantially opposing sides of the non-conducting member, the pair of electrodes are at least partially in alignment with each other;

moving the non-conducting member with respect to the pair of electrodes or one of the electrodes in the pair of electrodes with respect to the non-conducting member in response to a monitored pressure member in response to the monitored pressure; and

measuring the movement of the non-conducting member or one of the electrodes in the pair of electrodes; and

determining the monitored pressure based on the measured movement.

20. The method as set forth in claim 19 wherein the exposing the member or one of the electrodes in the pair of electrodes to a pressure to be measured further comprises exposing one of the first compartment and the second compartment to the monitored pressure through at least one opening extending into the exposed one of the first compartment and the second compartment, the other one of the first compartment and the second compartment is sealed at the reference pressure.

21. The method as set forth in claim 19 wherein the exposing the member or one of the pair of electrodes to a pressure to be measured further comprises exposing one of the electrodes in the pair of electrodes which is spaced from the member by the at least a portion of the chamber that is sealed at the reference pressure.

22. The method as set forth in claim 19 wherein moving the member with respect to the pair of electrodes or one of the electrodes in the pair of electrodes with respect to the member further comprises inducing a difference in electrical potential across the pair of electrodes.

23. The method as set forth in claim 22 wherein the measuring the movement further comprises measuring the difference in electrical potential across the pair of electrodes.

24. The method as set forth in claim 23 wherein the determining the monitored pressure further using the measure difference in electrical potential to determine the monitored pressure.