Interconnection system on a plane adjacent to a solid-state device structure

• US 20090261432A1
• Filed: 03/26/2009
• Published: 10/22/2009
• Est. Priority Date: 03/26/2008
• Status: Active Grant

• Current Assignee: PCB Piezotronics of North Carolina, Inc. (Amphenol Corporation)
• Original Assignee: Meggitt Incorporated (Amphenol Corporation)
• Inventors: Wilner, Leslie Bruce
• Granted Patent: US 8,115,265 B2
• Time in Patent Office: Days
• US Class Current: 257/418
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2207/07 Interconnects
• CPC Class Codes: B81B 7/0006 Interconnects
• CPC Class Codes: B81C 1/00238 Joining a substrate with an electronic processing unit and a substrate with a micromechanical structure
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/123 by piezo-resistive elements, e.g. semiconductor strain gauges
• 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

Abstract

An interconnection system is provided for a solid-state device. The solid-state that includes, a first layer, multiple devices and a first face. A second layer is bonded to the first face at a bonded face of the second layer that faces the first face. Electrically conductive bonds are between the first and second faces. Conductive paths are on the bonded face of the second layer and connect two or more of the conductive bonds.

Claims

1. An interconnection system for a solid-state device, comprising:

a solid-state device that includes, a first layer, multiple devices and a first face;

a second layer bonded to the first face at a bonded face of the second layer that faces the first face;

electrically conductive bonds between the first face and the bonded face; and

conductive paths on the bonded face of the second layer connecting two or more of the conductive bonds.

2. The system of claim 1, wherein the solid state device has a moveable portion that is moveable relative to an associated frame structure.

3. The system of claim 2, wherein motion of the moveable portion is monitored to produce a signal.

4. The system of claim 3, wherein motion of the moveable portion is not restrained by the second layer, and a corresponding area on the second layer is available for electrical coupling.

5. The system of claim 1, wherein conductive paths on the bonded face include paths for cross overs for circuitry on the first face.

6. The system of claim 1, wherein the first layer is silicon, and the second layer is made of a material that matches thermal expansion of silicon.

7. The system of claim 6, wherein the second layer is glass that is thermally expansion-matched to silicon.

8. The system of claim 1, further comprising:

a first metal film applied to the first face and a second metal film applied to the second face to provide for a diffusion bond interface.

9. The system of claim 1, wherein the solid state device is made of SOI.

10. The system of claim 9, wherein the SOI has a silicon dioxide insulator.

11. The system of claim 9, wherein the SOI has an insulator with a thickness in the range of about 0.2 to 3 microns.

12. The system of claim 1, wherein the first layer has a pattern of silicon on an oxide layer.

13. The system of claim 1, wherein the second layer is single crystal.

14. The system of claim 1, wherein a thickness of the first layer is from 0.5 micron to 4.0 microns.

15. The system of claim 1, wherein the solid state device is selected from at least one of, an accelerometer, pressure sensor, resonator and relay.

16. The system of claim 15, wherein the accelerometer is selected from at least one of, (i) single axis, linear, (ii) single axis, rotational, (iii) two-axis, (iv) three axis, (v) x-axis, rotational and linear, (vi) piezoresistive and (vii) variable capacitance.

17. An interconnection system for a MEMS device, comprising:

a MEMS device with contact points, including,

a silicon substrate with a face surface that has a pattern of recesses which define functional elements of the MEMS device leaving sharp-edged, highly doped to degeneracy ridges; and

a cover with a mating surface coupled to the face surface, the cover including patterns of metal films that engage the ridges to form connections from the face surface to the patterns of metal film on the mating surface.

18. The system of claim 17, wherein the sharp edge has a radius of curvature at the edge that is no great than 0.1 microns.

19. The system of claim 17, wherein the ridges have a doping of at least 10¹⁹ Bo atoms/cm³

20. The system of claim 17, wherein the mating surface is contoured.

21. The system of claim 18, wherein the mating surface is contoured in a range of 1 to 3 microns.

22. The system of claim 17, wherein the metal films are made of a material selected from at least one of aluminum, tin, copper, gold and silver.

23. The system of claim 17, wherein the MEMS device is an accelerometer and includes one or more seismic masses configured to pivot around pivot axes defined by pivot points between the seismic masses and a body of the silicon substrate.

24. The system of claim 23, wherein the seismic masses are formed in the silicon substrate.

25. The system of claim 24, wherein strain gauges are formed at the pivot points selectively doping the substrate to create piezoresistors that change resistance when the seismic masses pivot under acceleration.