Edge-mounted sensor

• US 8,987,840 B2
• Filed: 02/01/2011
• Issued: 03/24/2015
• Est. Priority Date: 02/01/2011
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Foster, Michael
• Primary Examiner(s): Sandvik, Benjamin
• Assistant Examiner(s): Cruz, Leslie Pilar
• Application Number:
  US13/019,175
• Publication Number:
  US 20120193731A1
• Time in Patent Office: 1,512 Days
• Field of Search: 257/414, 257/415, 257/417, 257/418, 257/419, 257/797, 257/E23.179, 438/5, 438/401
• US Class Current: 257/414
• CPC Class Codes: B81B 7/0074 3D packaging, i.e. encapsulation containing one or several MEMS devices arranged in planes non-parallel to the mounting board
• CPC Class Codes: H01L 23/544 Marks applied to semiconductor devices or parts, e.g. registration marks, alignment structures, wafer maps test patterns for characterising or monitoring manufacturing processes H01L22/00
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/1461 MEMS

Abstract

Sensor packages and methods for making a sensor device package for side mounting on a circuit board. A sensor device(s) in a mechanical layer of silicon is sandwiched between first and second layers of glass to create a wafer. A first via(s) is created in the first or second layers to expose a predefined area of the mechanical layer of silicon. A second via(s) is created in the first or second layers. The least one second via has a depth dimension that is less than a depth dimension of the first via. A metallic trace is applied between the exposed area on the mechanical layer and a portion of the second via. The wafer is sliced such that the second via is separated into two sections, thereby creating a sensor die. The sensor die is then electrically and mechanically bonded to a circuit board at the sliced second via.

Claims

1. A sensor die package comprising:

a mechanical layer of silicon that is bonded to a first layer of glass, the mechanical layer comprising a sensor device;

a second layer of glass attached to the mechanical layer of silicon;

at least one first via in at least one of the first or second layers of glass configured to expose a predefined area on a surface of the mechanical layer of silicon;

at least one second via in at least one of the first or second layers of glass, the at least one second via having a depth dimension that is less than a depth dimension of the at least one first via, wherein the at least one second via does not expose the mechanical layer of silicon and does not penetrate through the at least one of the first or second layers of glass in which the at least one second via is defined; and

a metallic trace located between the exposed area on the mechanical layer of silicon and at least a portion of the at least one second via,

wherein the at least one second via is open to an external surface of the at least one of the first or second layers of glass, the external surface facing away from the mechanical layer.

2. The package of claim 1, wherein the sensor device is hermetically sealed between the first or second layers of glass.

3. The package of claim 2, wherein the at least one sensor device comprises at least one of an accelerometer or a gyro.

4. The package of claim 1, wherein the predefined area on the surface of the mechanical layer of silicon exposed by the at least one first via includes an electrical trace that connects to the sensor device, and wherein the metallic trace electrically connects to the electrical trace.

5. The package of claim 1, wherein the at least one first via is defined by the first layer of glass and the at least one second via is defined by the second layer of glass.

6. The package of claim 1, wherein the at least one first via and the at least one second via are defined by the first layer of glass.

7. The package of claim 1, wherein the metallic trace extends between a bottom of the at least one second via and the predefined area on the surface of the mechanical layer of silicon, the bottom being defined by the at least one of the first or second layers of glass.

8. An accelerometer package comprising:

a first sensor die comprising;

a mechanical layer of silicon that is bonded to a first layer of glass, the mechanical layer comprising a sensor device;

a second layer of glass attached to the mechanical layer of silicon;

at least one first via in at least one of the first or second layers of glass configured to expose a predefined area on a surface of the mechanical layer of silicon;

at least one second via in at least one of the first or second layers of glass, the at least one second via having a depth dimension that is less than a depth dimension of the at least one first via, wherein the at least one second via does not expose the mechanical layer of silicon and does not penetrate through the at least one of the first or second layers of glass in which the at least one second via is defined;

a metallic trace located between the exposed area on the mechanical layer of silicon and at least a portion of the at least one second via,

wherein the at least one second via is open to an external surface of the at least one of the first or second layers of glass, the external surface facing away from the mechanical layer;

a circuit board;

second and third sensor dies formed from a wafer used for creation of the first sensor die, wherein each of the second and third sensor dies comprises a sensor device; and

a plurality of metallic beads configured to mechanically and electrically bond the first, second, and third dies to the circuit board such that sense axes for each of the sensor devices are perpendicular.

9. The package of claim 8, wherein the sensor devices are hermetically sealed between the first or second layers of glass.

10. The package of claim 8, wherein the sensor devices comprise at least one of accelerometers or gyros.

11. The package of claim 10, wherein the package comprises in-plane accelerometers configured to sense acceleration in three orthogonal axes.

12. The package of claim 8, wherein the predefined area on the surface of the mechanical layer of silicon exposed by the at least one first via includes an electrical trace that connects to the sensor device, and wherein the metallic trace electrically connects to the electrical trace.

13. The package of claim 8, wherein the at least one first via is defined by the first layer of glass and the at least one second via is defined by the second layer of glass.

14. The package of claim 8, wherein the at least one first via and the at least one second via are defined by the first layer of glass.

15. The package of claim 8, wherein the metallic trace extends between a bottom of the at least one second via and the predefined area on the surface of the mechanical layer of silicon, the bottom being defined by the at least one of the first or second layers of glass.

16. A method comprising:

creating at least one sensor device in a mechanical layer of silicon that is bonded to a first layer of glass;

attaching a second layer of glass to the mechanical layer of silicon to create a wafer;

creating at least one first via in at least one of the first or second layers of glass to expose a predefined area on a surface of the mechanical layer of silicon;

creating at least one second via in at least one of the first or second layers of glass, the at least one second via having a depth dimension that is less than a depth dimension of the at least one first via, wherein the at least one second via does not expose the mechanical layer of silicon and does not penetrate through the at least one of the first or second layers of glass in which the at least one second via is defined, and wherein the at least one second via is open to an external surface of the at least one of the first or second layers of glass, the external surface facing away from the mechanical layer; and

applying a metallic trace between the exposed area on the mechanical layer of silicon and at least a portion of the at least one second via.

17. The method of claim 16, wherein the sensor device is hermetically sealed between the first or second layers of glass.

18. The method of claim 16, wherein the at least one sensor device comprises at least one of an accelerometer or a gyro.