Three axis magnetic sensor device and method using flex cables

• US 9,423,473 B2
• Filed: 01/27/2015
• Issued: 08/23/2016
• Est. Priority Date: 08/17/2011
• Status: Active Grant

• Current Assignee: Movella Incorporated (Movella Holdings, Inc.)
• Original Assignee: mCube, Inc.
• Inventors: Wan, Hong, Flannery, Anthony F.
• Primary Examiner(s): Tran, Minh-Loan
• Assistant Examiner(s): Cruz, Leslie Pilar
• Application Number:
  US14/606,909
• Publication Number:
  US 20150137806A1
• Time in Patent Office: 574 Days
• US Class Current: 1/1
• CPC Class Codes: G01R 33/0206 Three-component magnetometers
• CPC Class Codes: G01R 33/093 using multilayer structures, e.g. giant magnetoresistance sensors thin magnetic films H01F10/00
• CPC Class Codes: G01R 33/096 anisotropic magnetoresistance sensors
• CPC Class Codes: G01R 33/098 comprising tunnel junctions, e.g. tunnel magnetoresistance sensors

Abstract

A method and structure for a three-axis magnetic field sensing device. An IC layer having first bond pads and second bond pads can be formed overlying a substrate/SOI member with a first, second, and third magnetic sensing element coupled the IC layer. One or more conductive cables can be formed to couple the first and second bond pads of the IC layer. A portion of the substrate member and IC layer can be removed to separate the first and second magnetic sensing elements on a first substrate member from the third sensing element on a second substrate member, and the third sensing element can be coupled to the side-wall of the first substrate member.

Claims

1. A device for sensing magnetic fields, the device comprising:

a first substrate member having a first surface region and a second surface region

a first integrated circuit (IC) layer spatially disposed overlying at least a portion of the first surface region of the first substrate member, the first IC layer having one or more bond pads;

a first magnetic field sensor element operably coupled to the first IC layer, the first magnetic field sensor element being configured to sense magnetic fields in a first spatial direction;

a second magnetic field sensor element operably coupled to the first IC layer, the second magnetic field sensing element being configured to sense magnetic fields in a second direction;

a second substrate member coupled to the first substrate member, the second substrate member having a first surface region and a second surface region, the second surface region of the second substrate member being coupled to the second surface region of the first substrate member;

a second IC layer spatially disposed overlying at least a portion of the first surface region of the second substrate member, the second IC layer having one or more bond pads;

a third magnetic field sensor element operably coupled to the second IC layer, the third magnetic sensing element being configured to sense magnetic fields in a third spatial direction; and

one or more conductive elements electrically coupling the first IC layer and the second IC layer, the one or more conductive elements being coupled to the bond pad of the first IC layer and the bond pad of the second IC layer.

2. The device of claim 1 wherein the one or more conductive elements are selected from a group of materials consisting of:

metals or metal alloys.

3. The device of claim 1 wherein the first substrate member and the second substrate member both comprise materials from a monolithic silicon substrate.

4. The device of claim 1 wherein the one or more conductive elements comprise a passivation or parylene material.

5. The device of claim 1 wherein the second surface region of the second substrate member is coupled to the second surface region of the first substrate member via a material selected from a group consisting of:

an adhesive material, a glue material.

6. The device of claim 1

wherein the first, second, and third magnetic field sensor elements are devices selected from a group consisting of:

anisotropic magneto-resistive (AMR) devices, giant magneto-resistive (GMR) devices, or tunnel junction magneto-resistive (TMR) devices, and

wherein the first spatial direction, the second spatial direction and the third spatial direction are orthogonal.

7. The device of claim 1 wherein the first magnetic field sensor element is configured to detect magnetic fields in the first spatial direction via being disposed in a first spatial orientation overlying the first surface region, the second magnetic field sensor element is configured to detect magnetic fields in the second spatial direction via being disposed in a second spatial orientation overlying the first surface region, and the third magnetic field sensor element is configured to detect magnetic fields in the third spatial direction via a vertically mounted orientation.

8. The device of claim 1

wherein the first surface region of the first substrate member comprises a horizontal surface and wherein the second surface region of the first substrate member comprises a vertical surface;

and

wherein the first surface region of the second substrate member comprises a top surface and wherein the second surface region of the second substrate member comprises a bottom surface.

9. A device for sensing magnetic fields, the device comprising:

a substrate member having a first surface region and a second surface region;

a first insulation material spatially disposed overlying the first surface region of the substrate, the first insulation material having a surface region;

a first integrated circuit (IC) layer spatially disposed overlying at least a portion of the surface region of the first insulation material, the first IC layer having one or more bond pads;

a first magnetic field sensor element operably coupled to the first IC layer, the first magnetic field sensor element being configured to detect at least in a first direction;

a second magnetic field sensor element operably coupled to the first IC layer, the second magnetic field sensing element being configured to detect at least in a second direction;

a second insulation material coupled the substrate member, the second insulation material having a first surface region and a second surface region, the second surface region of the second insulation material being coupled to the second surface region of the substrate member;

a second IC layer spatially disposed overlying at least a portion of the first surface region of the second insulator material, the second IC layer having one or more bond pads;

a third magnetic field sensor element operably coupled to the second IC layer, the third magnetic sensing element being configured to detect at least in a third direction; and

one or more conductive cables electrically coupling the first IC layer and the second IC layer, the one or more conductive cables being coupled to at least one of the bond pad(s) of the first IC layer and at least one of the bond pad(s) from the second IC layer.

10. The device of claim 9 wherein the one or more conductive cables comprises metals or metal alloys.

11. The device of claim 9 wherein the one or more conductive cables is coated with a passivation material or a parylene material.

12. The device of claim 9 wherein the substrate member, the first insulation material, and the second insulation material comprise materials from a monolithic silicon-on-insulator member.

13. The device of claim 9 wherein the second surface region of the second insulation material is coupled to the second surface region of the substrate member via a material selected from a group consisting of:

an adhesive material, a glue material.

14. The device of claim 9 wherein the first, second, and third magnetic field sensor elements are devices selected from a group consisting of:

comprise anisotropic magneto-resistive (AMR) devices, giant magneto-resistive (GMR) devices, or tunnel-junction magneto-resistive (TMR) devices.

15. The device of claim 9 wherein the first magnetic field sensor element is configured to detect magnetic fields in the first spatial direction via being disposed in a first spatial orientation overlying the first surface region, the second magnetic field sensor element is configured to detect magnetic fields in the second spatial direction via being disposed in a second spatial orientation overlying the first surface region, and the third magnetic field sensor element is configured to detect magnetic fields in the third spatial direction via a vertically mounted orientation.

16. The device of claim 9

wherein the first surface region of the substrate member comprises a horizontal surface and wherein the second surface region of the substrate member comprises a vertical surface;

and

wherein the first surface region of the second insulation material comprises a top surface and wherein the second surface region of the second insulation material comprises a bottom surface.

17. A device for sensing magnetic fields, the device comprising:

a first substrate member having a first surface region and a second surface region, the second surface region being perpendicular to the first surface region;

a first integrated circuit (IC) layer spatially disposed on at least a portion of the first surface region of the first substrate member, the first IC layer having one or more bond pads;

a first magnetic field sensor element disposed on the first surface region of the first substrate member and operably coupled to the first IC layer, the first magnetic field sensor element being configured to sense magnetic fields in a first spatial direction;

a second magnetic field sensor element operably coupled to the first IC layer, the second magnetic field sensing element being configured to sense magnetic fields in a second direction;

a second substrate member coupled to the first substrate member, the second substrate member having a first surface region and a second surface region, the second surface region being parallel to the first surface region, the second surface region of the second substrate member being coupled to the second surface region of the first substrate member, such that the first surface of the second substrate member is perpendicular to the first surface of the first substrate member;

a second IC layer spatially disposed overlying at least a portion of the first surface region of the second substrate member, the second IC layer having one or more bond pads;

a third magnetic field sensor element disposed on the first surface region of the second substrate member and operably coupled to the second IC layer, the third magnetic sensing element being configured to sense magnetic fields in a third spatial direction; and

one or more conductive elements electrically coupling the first IC layer and the second IC layer, the one or more conductive elements being coupled to the bond pad of the first IC layer and the bond pad of the second IC layer.

18. The device of claim 17 wherein the axis of the third magnetic field sensor element is perpendicular to the axis of the first magnetic field sensor element and the axis of third magnetic field sensor element.