FINGER SENSOR INCLUDING ENCAPSULATING LAYER OVER SENSING AREA AND RELATED METHODS

• US 20110309482A1
• Filed: 06/17/2011
• Published: 12/22/2011
• Est. Priority Date: 06/18/2010
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: AuthenTec Incorporated (Apple Inc.)
• Inventors: SALATINO, Matthew, Iantosca, Anthony
• Granted Patent: US 8,736,001 B2
• Time in Patent Office: Days
• US Class Current: 257/659
• CPC Class Codes: G06V 40/1329 Protecting the fingerprint sensor against damage caused by the finger
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48095 Kinked
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 23/3121 a substrate forming part of the encapsulation
• CPC Class Codes: H01L 23/3135 Double encapsulation or coating and encapsulation
• CPC Class Codes: H01L 24/48 of an individual wire connector
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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: H01L 2924/01014 Silicon [Si]
• CPC Class Codes: H01L 2924/01057 Lanthanum [La]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/10253 Silicon [Si]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/1815 Shape
• CPC Class Codes: H01L 2924/182 Disposition
• CPC Class Codes: Y10T 29/49117 : Conductor or circuit manufacturing

Abstract

A fingerprint sensor may include a substrate, and a finger sensing IC on the substrate and including a finger sensing area on an upper surface thereof for sensing an adjacent finger. The fingerprint sensor may include an encapsulating material on the finger sensing IC and covering the finger sensing area, and a bezel adjacent the finger sensing area and on an uppermost surface of the encapsulating layer.

Claims

1. A fingerprint sensor comprising:

a substrate;

a finger sensing integrated circuit (IC) on said substrate and comprising a finger sensing area on an upper surface thereof for sensing an adjacent finger;

an encapsulating material on said finger sensing IC and covering said finger sensing area; and

a bezel adjacent the finger sensing area and on an uppermost surface of said encapsulating layer.

2. The fingerprint sensor of claim 1 wherein said encapsulating material comprises a body portion covering said finger sensing area, and a flange portion extending from the periphery of said body portion;

and wherein said bezel is on said flange portion.

3. The fingerprint sensor of claim 1 wherein outer surfaces of said bezel are completely exposed;

and wherein said finger sensing area is completely covered by said encapsulating material.

4. The fingerprint sensor of claim 1 wherein said finger sensing area comprises an array of electric field sensing electrodes carried by the upper surface of said finger sensing IC.

5. The fingerprint sensor of claim 1 further comprising at least one drive circuit coupled to said bezel so that said bezel defines a drive electrode.

6. The fingerprint sensor of claim 1 further comprising at least one electrostatic discharge (ESD) circuit coupled to said bezel so that said bezel also defines an ESD electrode.

7. The fingerprint sensor of claim 1 further comprising:

a flexible circuit layer on said substrate and comprising a connector portion, said flexible circuit layer being on an opposite major surface of said substrate from that of said finger sensing IC; and

a switch carried by said flexible circuit layer.

8. The fingerprint sensor of claim 1 wherein said bezel comprises a solid metallic ring.

9. The fingerprint sensor of claim 1 wherein said bezel comprises an electrically conductive layer on said encapsulating material.

10. The fingerprint sensor of claim 1 further comprising at least one of a plurality of bond wires, a fan out circuitry interconnection, a flip chip interconnection, and a chip-on-tape interconnection for coupling said substrate and said finger sensing IC and being embedded in said encapsulating material.

11. A fingerprint sensor comprising:

a substrate;

a finger sensing integrated circuit (IC) on said substrate and comprising a finger sensing area on an upper surface thereof for sensing an adjacent finger, said finger sensing area comprising an array of electric field sensing electrodes;

an encapsulating material on said finger sensing IC and covering said finger sensing area;

a bezel adjacent the finger sensing area and on an uppermost surface of said encapsulating layer; and

at least one electrostatic discharge (ESD) circuit coupled to said bezel so that said bezel defines an ESD electrode.

12. The fingerprint sensor of claim 11 wherein said encapsulating material comprises a body portion covering said finger sensing area, and a flange portion extending from the periphery of said body portion;

and wherein said bezel is on said flange portion.

13. The fingerprint sensor of claim 11 wherein outer surfaces of said bezel are completely exposed;

and wherein said finger sensing area is completely covered by said encapsulating material.

14. The fingerprint sensor of claim 11 further comprising at least one drive circuit coupled to said bezel so that said bezel also defines a drive electrode.

15. The fingerprint sensor of claim 11 further comprising:

a flexible circuit layer on said substrate and comprising a connector portion, said flexible circuit layer being on an opposite major surface of said substrate from that of said finger sensing IC; and

a switch carried by said flexible circuit layer.

16. The fingerprint sensor of claim 11 wherein said bezel comprises an electrically conductive layer on said encapsulating material.

17. A method of making a fingerprint sensor comprising:

positioning a finger sensing integrated circuit (IC) on a substrate, the finger sensing IC comprising a finger sensing area on an upper surface thereof for sensing an adjacent finger;

forming an encapsulating material on the finger sensing IC and to cover the finger sensing area; and

positioning a bezel to be adjacent the finger sensing area and to be on an uppermost surface of the encapsulating layer.

18. The method of claim 17 wherein forming the encapsulating material comprises forming the encapsulating material to comprise a body portion covering the finger sensing area, and a flange portion extending from the periphery of the body portion, the bezel being positioned on the flange portion.

19. The method of claim 17 wherein positioning the bezel comprises positioning outer surfaces of the bezel to be completely exposed;

and wherein forming the encapsulating material comprises forming the encapsulating material so that the finger sensing area is completely covered thereby.

20. The method of claim 17 further comprising coupling at least one drive circuit to the bezel so that the bezel defines a drive electrode.

21. The method of claim 17 further comprising coupling at least one electrostatic discharge (ESD) circuit to the bezel so that the bezel also defines an ESD electrode.

22. The method of claim 17 further comprising:

coupling a flexible circuit layer on the substrate and comprising a connector portion, the flexible circuit layer being on an opposite major surface of the substrate from that of the finger sensing IC; and

positioning a switch to be carried by the flexible circuit layer.