FINGERPRINT SENSING MODULE AND METHOD FOR MANUFACTURING THE FINGERPRINT SENSING MODULE

• US 20180174018A1
• Filed: 11/09/2017
• Published: 06/21/2018
• Est. Priority Date: 12/15/2016
• Status: Active Grant

• Current Assignee: Fingerprint Cards AB
• Original Assignee: Fingerprint Cards AB
• Inventors: LUNDBERG, Nils, MO, Zhimin, SLOTTNER, Mats
• Granted Patent: US 10,395,164 B2
• Time in Patent Office: Days
• CPC Class Codes: G06K 19/07701 the record carrier comprising an interface suitable for human interaction
• CPC Class Codes: G06K 19/0772 Physical layout of the record carrier
• CPC Class Codes: G06K 19/145 at least one of the further markings being adapted for galvanic or wireless sensing, e.g. an RFID tag with both a wireless and an optical interface or memory, or a contact type smart card with ISO 7816 contacts and an optical interface or memory
• CPC Class Codes: G06K 19/18 Constructional details
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: G06V 40/1329 Protecting the fingerprint sensor against damage caused by the finger
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• 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 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/19107 off-chip wires

Abstract

There is provided a fingerprint sensing module comprising a fingerprint sensor device having a sensing array arranged on a first side of the device. The fingerprint sensor device also comprises connection pads for connecting the fingerprint sensor device to external circuitry and a fingerprint sensor device cover structure, the cover structure having a first side configured to be touched by a finger, and a second side facing the sensing array, wherein the cover structure comprises conductive traces, arranged on the second side, for electrically connecting the fingerprint sensor module to external circuitry, and wherein a surface area of the cover structure is larger than a surface area of the sensor device. Moreover, the fingerprint sensor device comprises wire-bonds electrically connecting the connection pads of the fingerprint sensing device to the conductive traces of the cover structure.

Claims

1. A fingerprint sensing module comprising:

a fingerprint sensor device having a sensing array arranged on a first side of the device, the sensing array comprising an array of fingerprint sensing elements, wherein said fingerprint sensor device comprises connection pads for connecting said fingerprint sensor device to external circuitry;

a fingerprint sensor device cover structure arranged to cover said fingerprint sensor device, said cover structure having a first side configured to be touched by a finger, thereby forming a sensing surface of said sensing module, and a second side facing said sensing array, wherein said cover structure comprises conductive traces arranged on the second side of the cover structure, for electrically connecting said fingerprint sensing module to external circuitry, and wherein a surface area of said cover structure is larger than a surface area of said sensor device;

wherein said fingerprint sensor device further comprises wire-bonds electrically connecting said connection pads of said fingerprint sensor device to said conductive traces of said cover structure.

2. The fingerprint sensing module according to claim 1, wherein said connection pads are arranged on a second side of said fingerprint sensor device, opposite of said first side of said fingerprint sensor device, said fingerprint sensor device further comprising a substrate comprising via connections reaching from said first side of said fingerprint senor device to said connection pads of said second side of said fingerprint sensor device.

3. The fingerprint sensing module according to claim 1, wherein said connection pads are arranged on said first side of said fingerprint sensor device, said fingerprint sensor device further comprising:

a carrier having a first side attached to said a second side of said fingerprint sensor device, opposite of said first side of said fingerprint sensor device;

wire-bonds between said connection pads of said fingerprint sensor device and said first side of said carrier; and

wire-bonds arranged between a second side of said carrier, opposite of said first side of said carrier, and said conductive traces of said cover structure.

4. The fingerprint sensing module according claim 1, further comprising mold layer arranged between said sensor device and said cover structure.

5. The fingerprint sensing module according to claim 1, wherein said cover structure is a laminate structure comprising at least one layer comprising conductive traces and at least one insulating layer.

6. The fingerprint sensing module according to claim 1, further comprising a passive component, arranged on said second side of said cover structure and electrically connected to the conductive traces of said cover structure.

7. The fingerprint sensing module according to claim 3, further comprising a passive component arranged on said first side of said carrier and electrically connected to conductive traces of said cover structure.

8. The fingerprint sensing module according to claim 1, further comprising:

a fingerprint sensor control device attached to a second side of said fingerprint sensor device, said second side being opposite of said first side of said fingerprint sensor device.

9. The fingerprint sensing module according to claim 8, further comprising wire-bonds electrically connecting said fingerprint sensor control device to conductive traces of said cover structure.

10. The fingerprint sensing module according to claim 8, further comprising a silicon interposer layer arranged between said fingerprint sensor control device and said second side of said fingerprint sensor device.

11. The fingerprint sensing module according to claim 1, further comprising an electrically conductive bezel arranged adjacent to said sensing array to provide an electrical connection between a finger placed on said sensing surface and drive signal circuitry of said fingerprint sensing module.

12. The fingerprint sensing module according to claim 1, wherein said cover structure extends outside of said fingerprint sensor device such that said fingerprint sensing module has a T-shaped profile.

13. The fingerprint sensing module according to claim 1, wherein said cover structure is flexible.

14. The fingerprint sensing module according to claim 1, further comprising a secure element.

15. A smart card comprising a fingerprint sensing module according to claim 1;

said smart card comprising a recess into which said fingerprint sensing module is arranged;

wherein said cover structure of said fingerprint sensing module comprises connection pads for connecting said conductive traces to corresponding connection pads of a conductive inlay of said smart card.

16. The smart card according to claim 15, wherein said recess has a shape corresponding to a shape of said fingerprint sensing module.

17. The smart card according to claim 15, wherein said recess is T-shaped and configured to receive a correspondingly T-shaped fingerprint sensing module.

21. A method for manufacturing a smart card comprising a fingerprint sensing module according to claim 1, the method comprising:

providing a smart card substrate comprising a plurality of layers;

forming a recess in said smart card, said recess comprising a lower portion and an upper portion, said upper portion having an area larger than an area of said lower portion;

forming via connections between said upper portion of said recess and conductive traces of the smart card; and

arranging a sensing module in said recess such that said conductive traces of said cover structure form an electrical contact with said via connections.

18. A method for manufacturing a fingerprint sensing module comprising:

providing a fingerprint sensor device having a sensing array arranged on a first side of the device, the sensing array comprising an array of fingerprint sensing elements, wherein said fingerprint sensor device comprises connection pads for connecting said fingerprint sensor device to external circuitry;

providing a fingerprint sensor device cover structure comprising conductive traces, arranged on the second side of the cover structure, for electrically connecting said fingerprint sensing module to the external circuitry;

attaching said fingerprint sensor device to said cover structure;

electrically connecting said fingerprint sensor device by means of wire bonding between said connections pads and said conductive traces.

19. The method according to claim 18, further comprising attaching a fingerprint sensor control device to a second side of said fingerprint sensor device, said second side being opposite of said first side of said fingerprint sensor device.

20. The method according to claim 18, further comprising encapsulating said fingerprint sensing module.