Capacitor electrode formed on surface of integrated circuit chip

• US 20070199385A1
• Filed: 11/17/2006
• Published: 08/30/2007
• Est. Priority Date: 11/18/2005
• Status: Abandoned Application

• Current Assignee: CardioMEMS Incorporated
• Original Assignee: CardioMEMS Incorporated
• Inventors: O'Brien, David, You, Liang
• Application Number:
  US11/601,597
• Publication Number:
  US 20070199385A1
• Time in Patent Office: Days
• US Class Current: 73/718
• CPC Class Codes: G01L 9/0075 using a ceramic diaphragm, e.g. alumina, fused quartz, glass

Abstract

A sensor has a sensor housing defining a cavity therein. A first wall partially defining the cavity is deflectable under a physiologically relevant range of pressures. An integrated circuit chip bearing electronics is fixedly mounted within the cavity. A capacitor comprises first and second capacitor plates in generally parallel, spaced-apart relation. The first capacitor plate is physically coupled to the deflectable wall so as to move as the wall deflects, and the second capacitor plate is carried by the chip. The second capacitor plate is in electrical communication with the input pad of the chip.

Claims

1. A sensor comprising:

a sensor housing defining a cavity therein, said housing comprising a first wall partially defining said cavity that is deflectable under a physiologically relevant range of pressures;

an integrated circuit chip bearing electronics, said chip being fixedly mounted within said cavity, and said chip having input and output pads;

a capacitor comprising first and second capacitor plates in generally parallel, spaced-apart relation, said first capacitor plate being physically coupled to said deflectable wall so as to move as said wall deflects, and said second capacitor plate being carried by said chip; and

means for placing said second capacitor plate in electrical communication with said input pad of said chip.

2. The sensor of claim 1,

wherein said housing comprises a second wall defining said cavity, said second wall being generally parallel to and spaced apart from said first wall;

and

wherein said chip being fixedly mounted within said cavity comprises said chip being mounted to said second wall.

3. The sensor of claim 2, further comprising a first electrical contact pad affixed to said second wall and in electrical communication with said output pad of said chip, wherein said chip is mounted to said second wall by said electrical contact pad.

4. The sensor of claim 3, further comprising a second electrical contact pad affixed to said second wall for mounting said chip to said second wall.

5. The sensor of claim 3, further comprising an electrical feedthrough extending from the cavity of said housing to the exterior of said housing and in electrical communication with said first electrical contact pad so as to allow electrical communication between said output pad of said chip and the exterior of said housing.

6. The sensor of claim 5, wherein said electrical feedthrough extends through said second wall.

7. The sensor of claim 1, wherein said housing is hermetic.

8. The sensor of claim 5, wherein said electrical feedthrough is hermetic.

9. The sensor of claim 1, wherein said second capacitor plate being carried by said chip comprises a layer of an insulating material being located on a surface of said chip facing said first capacitor plate, and said second capacitor plate being mounted to said layer of insulating material.

10. The sensor of claim 1, further comprising a third capacitor plate, said third capacitor plate being located generally co-planar with said second capacitor plate and spaced-apart therefrom, said third capacitor plate being carried by said chip, and said second and third capacitor plates being capacitively coupled to one another via said first capacitor plate.

11. The sensor of claim 10, wherein said chip further comprises a second input pad, and wherein said sensor further comprises means for placing said third capacitor plate in electrical communication with said second input pad of said chip.

12. The sensor of claim 10, wherein said second and third capacitor plates being carried by said chip comprises a layer of an insulating material being located on a surface of said chip facing said first capacitor plate, and said second and third capacitor plates being mounted to said layer of insulating material.

13. The sensor of claim 2, wherein said chip being mounted to said second wall comprises said chip being adhesively bonded to said second wall.