GLASS-ENCAPSULATED PRESSURE SENSOR

• US 20130127879A1
• Filed: 11/18/2011
• Published: 05/23/2013
• Est. Priority Date: 11/18/2011
• Status: Abandoned Application

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Burns, David William, Stephanou, Philip Jason, Shenoy, Ravindra V., Petersen, Kurt Edward
• Application Number:
  US13/299,645
• Publication Number:
  US 20130127879A1
• Time in Patent Office: Days
• US Class Current: 345/501
• CPC Class Codes: B81B 2201/0264 Pressure sensors
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81B 2207/012 the micromechanical device and the control or processing electronics being separate parts in the same package
• CPC Class Codes: B81B 2207/096 through the substrate
• CPC Class Codes: B81B 2207/097 Interconnects arranged on the substrate or the lid, and covered by the package seal
• CPC Class Codes: B81C 1/00238 Joining a substrate with an electronic processing unit and a substrate with a micromechanical structure
• CPC Class Codes: B81C 2203/0109 Bonding an individual cap on the substrate
• CPC Class Codes: B81C 2203/032 Gluing
• CPC Class Codes: B81C 2203/0792 Forming interconnections between the electronic processing unit and the micromechanical structure
• CPC Class Codes: G01L 19/0084 to the outside of the housing other details about the housing see G01L19/14
• CPC Class Codes: G01L 19/143 Two part housings
• CPC Class Codes: G01L 19/147 Details about the mounting of the sensor to support or covering means
• CPC Class Codes: G01L 19/148 Details about the circuit board integration, e.g. integrated with the diaphragm surface or encapsulation
• CPC Class Codes: G01L 9/0051 using variations in ohmic resistance
• CPC Class Codes: G01L 9/0072 using variations in capacitance
• CPC Class Codes: G01L 9/008 using piezoelectric devices piezoelectric resonators G01L9/0022; surface acoustic waves G01L9/0025
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 23/047 the other leads being parallel to the base
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/12044 : OLED
• CPC Class Codes: H01L 2924/1461 : MEMS
• CPC Class Codes: H01L 2924/15788 : Glasses, e.g. amorphous oxides, nitrides or fluorides
• CPC Class Codes: Y10T 29/5313 : Means to assemble electrical device

Abstract

This disclosure provides systems, methods and apparatus for glass-encapsulated pressure sensors. In one aspect, a glass-encapsulated pressure sensor may include a glass substrate, an electromechanical pressure sensor, an integrated circuit device, and a cover glass. The cover glass may be bonded to the glass substrate with an adhesive, such as epoxy, glass frit, or a metal bond ring. The cover glass may have any of a number of configurations. In some configurations, the cover glass may partially define a port for the electromechanical pressure sensor at an edge of the glass-encapsulated pressure sensor. In some configurations, the cover glass may form a cavity to accommodate the integrated circuit device that is separate from a cavity that accommodates the electromechanical pressure sensor.

Claims

1. An apparatus comprising:

a glass substrate;

an electromechanical pressure sensor disposed on a surface of the glass substrate;

a cover glass bonded to the surface of the glass substrate with a joining ring, wherein the cover glass includes a first recess that forms a first cavity when the cover glass is bonded to the surface of the glass substrate, the first cavity being configured to accommodate the electromechanical pressure sensor, and

a port in at least one of the glass substrate, joining ring, or cover glass providing fluidic access to the pressure sensor.

2. The apparatus of claim 1, further comprising an integrated circuit device disposed on the surface of the glass substrate, the integrated circuit device configured to sense output from the electromechanical pressure sensor.

3. The apparatus of claim 2, wherein the first cavity is further configured to accommodate the integrated circuit device.

4. The apparatus of claim 2, wherein the cover glass further includes a second recess that forms a second cavity when the cover glass is bonded to the surface of the glass substrate, the second cavity being configured to accommodate the integrated circuit device.

5. The apparatus of claim 4, wherein the second cavity is isolated from the first cavity by the joining ring.

6. The apparatus of claim 4, wherein the second cavity is hermetically sealed.

7. The apparatus of claim 1, wherein the port is partially defined by the first recess.

8. The apparatus of claim 1, wherein the port is partially defined by one or more channels in the joining ring.

9. The apparatus of claim 1, further comprising a feature in the port partially obstructing fluid access to the pressure sensor.

10. The apparatus of claim 1, wherein the cover glass bonded to the glass substrate forms a glass die having a plurality of side surfaces and further wherein the port is in one of the plurality of side surfaces.

11. The apparatus of claim 1, wherein the cover glass bonded to the glass substrate forms a glass die having a plurality of side surfaces disposed between parallel major surfaces of the glass substrate and cover glass, and wherein the port is in one of the parallel major surfaces.

12. The apparatus of claim 1, further comprising through-glass via interconnects in at least one of the cover glass and the glass substrate.

13. The apparatus of claim 1, wherein the joining ring includes at least one of a metal bond ring, an epoxy, or a glass frit.

14. The apparatus of claim 1, wherein a thickness of the glass substrate is about 50 to 700 microns, and wherein a thickness of the cover glass is about 50 to 700 microns.

15. The apparatus of claim 1, wherein the port has a smallest dimension of between about 0.2 microns and 300 microns.

16. The apparatus of claim 1, wherein the glass substrate and the cover glass serve as packaging for the electromechanical pressure sensor.

17. The apparatus of claim 1, further comprising a plurality of bond pads on a surface of the cover glass or the glass substrate configured to attach to a flexible connector.

19. The apparatus of claim 17, wherein the bond pads are on a ledge formed by the cover glass extending past a side surface of the glass substrate.

20. The apparatus of claim 17, further comprising:

a flexible connector, the flexible connector including;

a plurality of flex pads at a first end of the flexible connector;

a plurality of contacts at a second end of the flexible connector; and

a plurality of electrical connections connecting each of the plurality of flex pads with a contact of the plurality of contacts,

wherein each of the plurality of flex pads is in electrical contact with a bond pad of the plurality of bond pads.

21. The apparatus of claim 1, wherein the cover glass further includes a second recess that forms a second cavity when the cover glass is bonded to the surface of the glass substrate.

22. The apparatus of claim 1, further comprising:

a display;

a processor that is configured to communicate with the display, the processor being configured to process image data; and

a memory device that is configured to communicate with the processor.

23. The apparatus of claim 22, further comprising:

a driver circuit configured to send at least one signal to the display; and

a controller configured to send at least a portion of the image data to the driver circuit.

24. The apparatus of claim 23, further comprising:

an image source module configured to send the image data to the processor, wherein the image source module includes at least one of a receiver, transceiver, and transmitter.

25. The apparatus of claim 22, further comprising:

an input device configured to receive input data and to communicate the input data to the processor.

18. The apparatus of 17, wherein the bond pads are on a ledge formed by the glass substrate extending past a side surface of the cover glass.

26. An apparatus comprising:

means for encapsulating an electromechanical pressure sensor inside a package;

means for transmitting a fluidic pressure from an outside of the package to the electromechanical pressure sensor;

means for converting a fluidic pressure within the electromechanical pressure sensor into an electrical signal; and

means for transmitting an electrical signal from the electromechanical pressure sensor to the exterior of the package.

27. The apparatus of claim 26, further comprising means for conditioning the electrical signal generated by the electromechanical pressure sensor.

28. The apparatus of claim 26, further comprising means for hermetically sealing an integrated circuit device encapsulated inside the package.

29. A method comprising:

providing a glass substrate, the glass substrate having an electromechanical pressure sensor and an integrated circuit device disposed on a surface of the glass substrate, the integrated circuit device configured to sense output from the electromechanical pressure sensor; and

bonding a cover glass to the surface of the glass substrate, wherein the cover glass includes a first recess that forms a first cavity when the cover glass is bonded to the surface of the glass substrate, the first cavity being configured to accommodate the electromechanical pressure sensor.

30. The method of claim 29, wherein a portion of the first recess is at an edge of the cover glass such that when the cover glass is bonded to the surface of the glass substrate, a port is formed, the port configured to allow a pressure signal to interact with the electromechanical pressure sensor.

31. The method of claim 29, wherein the bonding is performed with at least one of a metal bond ring or an epoxy.