Pressure sensor with expanding member

• US 7,418,870 B2
• Filed: 02/13/2006
• Issued: 09/02/2008
• Est. Priority Date: 02/28/2005
• Status: Expired due to Fees

• Current Assignee: Zin Technologies, Inc.
• Original Assignee: Zin Technologies, Inc.
• Inventors: Izadnegahdar, Alain
• Primary Examiner(s): Allen; Andre J
• Application Number:
  US11/352,629
• Publication Number:
  US 20060191349A1
• Time in Patent Office: 932 Days
• Field of Search: 737/08, 737/291, 737/54, 257/415, 257/417
• US Class Current: 73/754
• CPC Class Codes: G01L 15/00 Devices or apparatus for measuring two or more fluid pressure values simultaneously
• CPC Class Codes: G01L 19/04 Means for compensating for effects of changes of temperature , i.e. other than electric compensation
• CPC Class Codes: G01L 9/0019 of a semiconductive element
• CPC Class Codes: G01L 9/065 with temperature compensating means non electric temperature compensating means G01L19/04
• CPC Class Codes: G01L 9/125 with temperature compensating means non electric temperature compensating means G01L19/04

Abstract

Systems and methodologies that provide for multi-parameter sensing via micro fabricated sensing structures operatively connected to oscillators, each micro-fabricated sensing structure in part defines a frequency of a respective associated oscillator. Output from such oscillators can be combined together, and then AC coupled with an incoming DC voltage that feeds the oscillators. The wiring arrangement includes two conducting paths/wires that carry a direct current to the oscillators as well as outputting the combined signal to external measurement devices. In addition, arrangements for pressure sensors are provided that mitigate errors from temperature variations and the induced stress/strains.

Claims

1. A micro-fabricated pressure sensor, comprising:

a pressure sensing element; and

a free expanding member formed as a result of a connection of a base of the micro-fabricated pressure sensor to a package, such that a connection area therebetween is less than an area of the base, the free expanding member mitigates effects of at least one of temperature induced stress and strains on the pressure sensing element.

2. The micro-fabricated pressure sensor of claim 1, the micro-fabricated pressure sensor with a step structure that forms the connection area.

3. The micro-fabricated pressure sensor of claim 1, the pressure sensing element operates based on at least one of a resonator, capacitive structures and piezoresistive.

4. The micro-fabricated pressure sensor of claim 1, the pressure sensing element positioned on the free expanding member.

5. The micro-fabricated pressure sensor of claim 1, the pressure sensing element comprising an encapsulation that relative thereto, a pressure of surrounding environment is measured.

6. The micro-fabricated pressure sensor of claim 1, the free expanding member with a uniform thermal expansion coefficient to provide a zone that mitigates thermal stresses or strains.

7. The micro-fabricated pressure sensor of claim 1, the free expanding member comprising silicone carbide.

8. The micro-fabricated pressure sensor of claim 1, the pressure sensing element further sensitive to temperature.

9. The micro-fabricated pressure sensor of claim 1, further comprising a wire connectable portion for attaching a wire thereto.

10. The micro-fabricated pressure sensor of claim 4 the free expanding member expandable to mitigate at least one of a strain and stress on the pressure sensing element.

11. A method of measuring a pressure via a pressure sensor comprising:

connecting a base of the pressure sensor to a package to form a connection area, the connection area smaller than an area of the base; and

forming a free expanding member from the connecting act, to reduce stress or strain on a sensing element associated with the pressure sensor.

12. The method of claim 11 further comprising forming a step shaped structure on the base.

13. The method of claim 11 further comprising positioning a sensing element associated with the pressure sensor on the free expanding member.

14. The method of claim 13 further comprising expanding the free expanding member as a result of pressure or temperature induced on the pressure sensor.

15. The method of claim 14 further comprising contracting the free expanding member.

16. The method of claim 14 further comprising mitigating a deformation on the sensing element.

17. The method of claim 14, further comprising measuring a pressure of a surrounding environment relative to the sensing element.

18. The method of claim 14 further comprising providing a zone within the expanding member to absorb stresses or strains therein.

19. A micro-fabricated pressure sensor comprising:

means for forming a free expandable member; and

means for reducing a strain or stress on a sensing means of the pressure sensor;

means for reducing a contact area of the pressure sensor to a package.