Fingerprint sensing assemblies and methods of making

Patent metadata

Field	Value
Publication number	US-2016055365-A1
Application number	US-201514930352-A
Country	US
Kind code	A1
Filing date	Nov 2, 2015
Priority date	Oct 4, 2004
Publication date	Feb 25, 2016
Grant date	—

Abstract

A fingerprint sensing module includes a sensor substrate having a sensing side and a circuit side, an image sensor including conductive traces on the circuit side of the sensor substrate, and a sensor circuit including at least one integrated circuit mounted on the circuit side of the sensor substrate and electrically connected to the image sensor. The sensor substrate may be a flexible substrate. The module may include a velocity sensor on the sensor substrate or on a separate substrate. The module may further include a rigid substrate, and the sensor substrate may be affixed to the rigid substrate.

First claim

1 . A fingerprint sensing module comprising:
a rigid substrate having a cutout; a flexible substrate attached to the rigid substrate; an image sensor including conductive traces formed on the flexible substrate; and a sensor integrated circuit that is connected to the conductive traces of the image sensor, wherein the sensor integrated circuit is disposed in the cutout of the rigid substrate.

2 . The fingerprint sensing module of claim 1 , wherein the sensor integrated circuit is flip chip bonded to the flexible substrate.

3 . The fingerprint sensing module of claim 1 , wherein the flexible substrate is attached to the rigid substrate with an adhesive.

4 . The fingerprint sensing module of claim 1 , wherein the sensor integrated circuit is fully enclosed in the cutout.

5 . The fingerprint sensing module of claim 1 , wherein the sensor integrated circuit is disposed between the flexible substrate and the rigid substrate.

6 . The fingerprint sensing module of claim 1 , wherein the flexible substrate has a sensing side and a circuit side, wherein the conductive traces of the image sensor are formed on the circuit side of the flexible substrate, and wherein a finger of a user is configured to be received from the sensing side of the flexible substrate.

7 . The fingerprint sensing module of claim 1 , further comprising electrical interconnects formed on the rigid substrate.

8 . The fingerprint sensing module of claim 1 , wherein the rigid substrate comprises vias interconnecting different layers.

9 . The fingerprint sensing module of claim 1 , wherein the image sensor comprises an array of capacitive sensors for capacitive sensing of ridge peaks and ridge valleys of a fingerprint on a finger.

10 . The fingerprint sensing module of claim 9 , wherein the image sensor comprises a plurality of sensor gaps between respective image drive plates and image pickup plates, wherein the ridge peaks and ridge valleys of the fingerprint over the sensor gaps produce a change in capacitance between the respective image drive plates and image pickup plates.

11 . The fingerprint sensing module of claim 1 , wherein the conductive traces on the flexible substrate form a plurality of sensor gaps between respective image drive plates and image pickup plates.

12 . The fingerprint sensing module of claim 11 , wherein the ridge peaks and ridge valleys of the fingerprint over the sensor gaps produce a change in capacitance between the respective image drive plates and image pickup plates.

13 . A method of forming a fingerprint sensing module, the method comprising:
forming a rigid substrate having a cutout; forming an image sensor including conductive traces on a flexible substrate; connecting a sensor integrated circuit to the conductive traces of the image sensor; and attaching the flexible substrate to the rigid substrate, wherein the sensor integrated circuit is disposed in the cutout of the rigid substrate.

14 . The method of claim 13 , wherein the connecting the sensor integrated circuit comprises flip chip bonding the sensor integrated circuit to the flexible substrate.

15 . The method of claim 13 , wherein the attaching the flexible substrate comprises attaching the flexible substrate to the rigid substrate with an adhesive.

16 . The method of claim 13 , wherein the sensor integrated circuit is fully enclosed in the cutout.

17 . The method of claim 13 , wherein the sensor integrated circuit is disposed between the flexible substrate and the rigid substrate.

18 . The method of claim 13 , wherein the forming the image sensor including conductive traces comprises forming an array of capacitive sensors for capacitive sensing of ridge peaks and ridge valleys of a fingerprint on a finger.

19 . The method of claim 13 , wherein the forming the image sensor including conductive traces comprises forming a plurality of sensor gaps between respective image drive plates and image pickup plates.

20 . A sensing module comprising:
a rigid substrate having a cutout; a flexible substrate attached to the rigid substrate; a sensor including conductive traces formed on the flexible substrate; and a sensor integrated circuit that is connected to the conductive traces of the sensor, wherein the sensor integrated circuit is disposed in the cutout of the rigid substrate.

Assignees

• Synaptics Inc

Inventors

• Benkley Iii Fred G

Classifications

• Y10T29/4913

  Assembling to base an electrical component, e.g., capacitor, etc. · CPC title

• G06K9/00053 Primary

  Physics · mapped topic

• G06K9/0002

  Physics · mapped topic

• G06V40/1329 Primary

  Protecting the fingerprint sensor against damage caused by the finger · CPC title

• G06V40/1359

  Extracting features related to ridge properties; Determining the fingerprint type, e.g. whorl or loop · CPC title