Capacitive sensor packaging

• US 10,007,832 B2
• Filed: 12/29/2016
• Issued: 06/26/2018
• Est. Priority Date: 05/18/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Pope, Benjamin J., Arnold, Shawn, Corlett, Barry J., Gilton, Terry L., Husaini, Syed, Webster, Steven, Myers, Scott A., Hill, Matthew D., Lyon, Benjamin B.
• Primary Examiner(s): HICKS, CHARLES V
• Application Number:
  US15/393,610
• Publication Number:
  US 20170109565A1
• Time in Patent Office: 544 Days
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: G06V 40/1318 using electro-optical elements or layers, e.g. electroluminescent sensing
• CPC Class Codes: G06V 40/1329 Protecting the fingerprint sensor against damage caused by the finger
• CPC Class Codes: G06V 40/1353 Extracting features related to minutiae or pores
• CPC Class Codes: G06V 40/1365 Matching; Classification

Abstract

An apparatus comprises a fingerprint sensor having a set of capacitive elements configured for capacitively coupling to a user fingerprint. The fingerprint sensor may be disposed under a control button or display element of an electronic device, for example one or more of a control button and a display component. A responsive element is responsive to proximity of the user fingerprint, for example one or both of a first circuit responsive to motion of the control button, and a second circuit responsive to a coupling between the fingerprint and a surface of the display element. The fingerprint sensor is disposed closer to the fingerprint than the responsive element. The control button or display component may include an anisotropic dielectric material, for example sapphire.

Claims

1. An electronic device, comprising:

a cover layer comprising an opening;

a display positioned below the cover layer;

a structure positioned adjacent to the display and within the opening; and

an input device, comprising;

a top element positioned within the opening and surrounded by the structure;

a fingerprint sensor positioned below the top element;

a flexible circuit positioned below and electrically connected to the fingerprint sensor; and

a stiffener positioned below the flexible circuit and affixed to the structure.

2. The electronic device of claim 1, wherein:

the flexible circuit comprises a first flexible circuit; and

the input device further comprises;

a second flexible circuit positioned below the stiffener; and

a control element positioned below and electrically connected to the second flexible circuit, the control element responsive to a pressure applied to the input device.

3. The electronic device of claim 2, wherein the second flexible circuit is electrically connected to the first flexible circuit.

4. The electronic device as in claim 1, wherein the top element is comprised of a sapphire material having a planar axis perpendicular to a C-plane of the sapphire material, the planar axis extending between the fingerprint sensor and a top surface of the top element.

5. The electronic device as in claim 1, wherein the fingerprint sensor comprises a sensor circuit electrically connected to one or more bonding wires disposed through one or more edge trenches formed in a wafer.

6. The electronic device as in claim 1, wherein at least a portion of a top surface of the top element is recessed with respect to the cover layer.

7. The electronic device as in claim 1, wherein the top element is recessed at least partially by a chamfer in the structure.

8. The electronic device as in claim 1, wherein the top element has a substantially flat top surface.

9. The electronic device as in claim 1, wherein the structure electrically isolates the fingerprint sensor.

10. The electronic device as in claim 1, wherein the cover layer is comprised of a sapphire material.

11. An input device, comprising:

a button;

a fingerprint sensor positioned below the button;

a flexible circuit positioned below and electrically connected to the fingerprint sensor;

a stiffener positioned below the flexible circuit; and

a layer of electrically conductive material positioned between at least one of;

the fingerprint sensor and the flexible circuit and configured to conduct signals between the fingerprint sensor and the flexible circuit;

or

the button and the fingerprint sensor and configured to conduct signals between the button and the fingerprint sensor.

12. The input device of claim 11, wherein:

the flexible circuit comprises a first flexible circuit; and

the input device further comprises;

a second flexible circuit positioned below the stiffener; and

a control element positioned below and electrically connected to the second flexible circuit, the control element responsive to a pressure applied to the button.

13. The input device of claim 12, wherein the control element comprises a switch.

14. The input device of claim 13, further comprising:

a switch gasket positioned below the switch and configured to support the switch; and

a support plate positioned below the switch gasket and configured to support the switch gasket.

15. The input device as in claim 11, wherein the button is comprised of a sapphire material having a planar axis perpendicular to a C-plane of the sapphire material, the planar axis extending between the fingerprint sensor and a top surface of the button.

16. The input device as in claim 11, wherein at least a portion of a top surface of the button is recessed with respect to a cover layer.

17. The input device as in claim 11, wherein a top surface of the button is substantially flat with respect to a cover layer.

18. The input device as in claim 11, wherein the fingerprint sensor comprises a sensor circuit electrically connected to one or more bonding wires disposed through one or more edge trenches formed in a wafer.

19. The input device as in claim 11, wherein the layer of electrically conductive material is encapsulated in a resin.

20. The input device as in claim 11, wherein the layer of electrically conductive material comprises a layer of solder balls.

21. The input device of claim 11, wherein the fingerprint sensor comprises a capacitive fingerprint sensor.