Magnetic sensor device and a method for fabricating the same

• US 9,201,123 B2
• Filed: 11/04/2011
• Issued: 12/01/2015
• Est. Priority Date: 11/04/2011
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Elian, Klaus, Mueller, Thomas
• Primary Examiner(s): Assouad, Patrick
• Assistant Examiner(s): BROWN, LAMARR A
• Application Number:
  US13/289,735
• Publication Number:
  US 20130113475A1
• Time in Patent Office: 1,488 Days
• Field of Search: 324/244, 324/219, 324/260, 324/207.23, 324/207.24, 324/207.25, 324/173, 324/174, 324/207.2, 324/207.21
• US Class Current: 1/1
• CPC Class Codes: G01R 33/0047 Housings or packaging of magnetic sensors packaging of semiconductor devices H01L23/00; Holders
• CPC Class Codes: H01F 1/083 in a bonding agent
• CPC Class Codes: H01F 1/113 in a bonding agent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/49227 Insulator making

Abstract

A magnetic sensor device includes a plurality of electrical wires, a magnetic sensor chip, and a magnet. The magnet is formed from a material composition of a polymer and magnetic particles and attached to at least one of the electrical wires.

Claims

1. A magnetic sensor device comprising:

a magnetic sensor chip;

a plurality of electrical wires; and

a permanent magnet configured to generate a bias magnetic field, the permanent magnet being arranged so that at least one of the electrical wires of the plurality of electrical wires extends through opposing parallel side faces of the permanent magnet.

2. The magnetic sensor device according to claim 1, wherein the at least one of the electrical wires is completely embedded within a material composition along a line section of an electrical wire of the plurality of electrical wires.

3. The magnetic sensor device according to claim 2, wherein the at least one of the electrical wires, to which the material composition is attached, are covered by an electrically insulating layer along respective line sections thereof.

4. The magnetic sensor device according to claim 1, wherein the permanent magnet comprises a shape of a cube or cuboid.

5. A magnetic sensor device comprising:

a leadframe comprising leadfingers;

a magnetic sensor chip attached to at least one of the leadfingers;

a magnet comprising a first material composition of a polymer and magnetic particles, the first material composition being attached to at least one of the leadfingers; and

an encapsulant comprising a second material composition different from the first material composition, the encapsulant encapsulating the magnetic sensor chip.

6. The magnetic sensor device according to claim 5, wherein the first material composition is attached to the at least one of the leadfingers in such a way that the at least one of the leadfingers extends through the first material composition.

7. The magnetic sensor device according to claim 5, wherein the first material composition is attached to the at least one of the leadfingers in such a way that the at least one of the leadfingers is completely embedded within the first material composition along a line section of the leadfingers.

8. The magnetic sensor device according to claim 5, wherein the at least one of the leadfingers, to which the first material composition is attached, are covered by an electrically insulating layer along respective line sections thereof.

9. A method for fabricating a magnetic sensor device, the method comprising:

providing a plurality of electrical wires;

providing a magnetic sensor chip; and

attaching a magnet to at least one of the electrical wires, the magnet comprising a material composition of a polymer and magnetic particles, wherein the at least one of the electrical wires extends through opposing parallel sides faces of the magnet.

10. The method according to claim 9, further comprising molding the material composition to the at least one of the electrical wires.

11. The method according to claim 9, further comprising covering the at least one of the electrical wires, to which the material composition is to be attached, with an electrically insulating layer along respective line sections thereof.

12. The method according to claim 9, wherein the magnet has a shape of a cube or cuboid or a shape deviating from a shape of a cube or cuboid insofar as in a surface adjacent to the magnetic sensor chip a depression is formed.

13. A method for fabricating a magnetic sensor device, the method comprising:

providing a leadframe comprising a plurality of leadfingers;

providing a magnetic sensor chip; and

molding a material composition of a polymer and magnetic or magnetizable particles on or around at least one of the leadfingers, wherein the material composition molded on or around at least one of the leadfingers does not cover the magnetic sensor chip.

14. The method according to claim 13, further comprising covering those of the leadfingers on or around which the material composition is to be molded with an electrically insulating layer.

15. The method according to claim 13, further comprising molding the material composition to a shape of a cube or cuboid or to a shape deviating from a shape of a cube or cuboid insofar as in a surface adjacent to the magnetic sensor chip a depression is formed.