Touch screen, method of manufacturing touch screen, and display device including touch screen

Patent metadata

Field	Value
Publication number	US-10613689-B2
Application number	US-201715574584-A
Country	US
Kind code	B2
Filing date	Mar 15, 2017
Priority date	Sep 12, 2016
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

The present disclosure relates generally to a method for manufacturing a touch screen, a touch screen, and a display device having a touch screen. An embodiment of the method for manufacturing a touch screen may include forming a touch sensor and a fingerprint sensor concurrently on a glass substrate; thinning the glass substrate at a portion facing the fingerprint sensor to a predetermined thickness.

First claim

What is claimed is:

1. A method of manufacturing a touch screen, comprising:
forming a black matrix pattern on a glass substrate, the black matrix pattern comprising a first black matrix, a second black matrix, and a third black matrix arranged consecutively, so that an area of the glass substrate between the first black matrix and the second black matrix defines a display portion of the touch screen, and an area of the glass substrate between the second black matrix and the third black matrix defines a fingerprint recognition portion of the touch screen,
after forming the black matrix pattern, performing a first patterning step to form a patterned electrode layer on the glass substrate by using a first single mask, the patterned electrode layer comprising a plurality of first electrodes forming the touch sensor on a first portion of the glass substrate in the display portion, and a plurality of second electrodes forming a first component of the fingerprint sensor on a second portion of the glass substrate in the fingerprint recognition portion, wherein the plurality of second electrodes comprises a plurality, of fingerprint sensing electrodes,
performing a second patterning step to form a first insulating layer on the patterned electrode layer by using a second single mask,
performing a third patterning step to form a first patterned metal layer covering the insulating layer and the patterned electrode layer by using a third single mask, the first patterned metal layer comprising a plurality of metal electrodes forming a second component of the fingerprint sensor, wherein the plurality of metal electrodes comprises a plurality of fingerprint recognition control electrodes, and
performing a fourth patterning step using a fourth single mask to form a second patterned metal layer, the second patterned metal layer comprising a plurality of metal control electrodes on the plurality of fingerprint recognition control electrodes, a plurality of metal sensing electrodes on the plurality of fingerprint sensing electrodes, and a metal trace on the first black matrix, the second black matrix, and the third black matrix,
wherein in the fourth patterning step, a pattern of the plurality of metal control electrodes corresponds to a pattern of the plurality of fingerprint recognition control electrodes, a pattern of the plurality of metal sensing electrodes corresponds to a pattern of the plurality of the fingerprint sensing electrodes, a first portion of the metal trace on the first black matrix and the second black matrix extends along at least a portion of a periphery of the display portion, and a second portion of the metal trace on the third black matrix extends along at least a portion of a periphery of the fingerprint recognition portion,
wherein the patterned electrode layer, the insulating layer and the patterned metal layer form a touch sensor and a fingerprint sensor, and
wherein the method further comprises, after the fourth patterning step, providing a protective layer on the fingerprint sensor, reducing a thickness of a portion of the glass substrate facing the fingerprint sensor to less than or equal to 0.1 mm, and removing the protective layer.

2. The method according to claim 1 ,
wherein the plurality of first electrodes comprise a plurality of touch sensing electrodes arranged in a first direction, and a plurality of touch control electrodes arranged in a second direction, and
wherein the plurality of touch sensing electrodes intersect the plurality of touch control electrodes, and one of the plurality of touch sensing electrodes and the plurality of touch control electrodes are discontinuous at positions of intersection.

3. The method according to claim 1 ,
wherein the first patterned metal layer further comprises a plurality of metal bridges for connecting the first electrodes.

4. The method according to claim 3 ,
wherein each of the plurality of metal bridges is formed on the first electrodes, so as to connect two ends of discontinuous one of touch sensing electrode and touch control electrode at a position of intersection.

5. The method according to claim 1 ,
wherein the plurality of first electrodes and the plurality of second electrodes are composed of a transparent conductive material.

6. The method according to claim 1 , further comprising forming a cover layer, wherein the cover layer does not cover at least a portion of the metal trace, so as to form a bonding area opening for electrically connecting the portion of the metal trace to an external circuit.

7. The method according to claim 1 ,
wherein before forming the patterned electrode layer on the glass substrate, the method further comprises:
forming a conductive bridge layer on the glass substrate, the conductive bridge layer comprising a first array of first conductive bridges arranged on a portion of the glass substrate in the display portion, and a second array of second conductive bridges on a portion of the glass substrate in the fingerprint recognition portion, and
forming a second insulation layer on the conductive bridge layer.

8. The method according to claim 7 ,
wherein the first electrodes comprise a plurality of touch sensing electrodes arranged in a first direction, and a plurality of touch control electrodes arranged in a second direction, and
wherein the plurality of touch sensing electrodes intersect the plurality of touch control electrodes, and one of the plurality of touch sensing electrodes and the plurality of touch control electrodes are discontinuous at positions of intersection, each of the first conductive bridges connecting two ends of discontinuous one of touch sensing electrode and touch control electrode at a position of intersection.

9. The method according to claim 7 , wherein the plurality of fingerprint sensing electrodes are arranged in a first direction, and the plurality of fingerprint recognition control electrodes are arranged in a second direction, and
wherein the plurality of fingerprint sensing electrodes intersect the plurality of fingerprint recognition control electrodes, and one of the plurality of fingerprint sensing electrodes and the plurality of fingerprint recognition control electrodes are discontinuous at positions of intersection, each of the second conductive bridges connecting two ends of discontinuous one of touch sensing electrode and touch control electrode at a position of intersection.

10. The method according to claim 7 , further comprising forming a cover layer, wherein the cover layer does not cover at least a portion of the metal trace, so as to form a bonding area opening for electrically connecting the portion of the metal trace to an external circuit.

11. A touch screen, comprising:
a glass substrate,
a black matrix layer on the glass substrate, the black matrix layer comprising a first black matrix, a second black matrix, and a third black matrix arranged consecutively, so that an area of the glass substrate between the first black matrix and the second black matrix defines a display portion of the touch screen, and an area of the glass substrate between the second black matrix and the third black matrix defines a fingerprint recognition portion of the touch screen,
a touch sensor disposed on a first portion of the glass substrate in the display portion, and
a fingerprint sensor disposed on a second portion of the glass substrate in the fingerprint recognition portion,
wherein a thickness of the second portion of the glass substrate facing the fingerprint sensor is smaller than a thickness of the first portion of the glass substrate facing the touch sensor,
wherein the touch sensor comprises a plurality of touch sensing electrodes and a pl

Assignees

• Boe Technology Group Co Ltd
• Hefei Xinsheng Optoelectronics Technology Co Ltd

Inventors

• Zhang Lei
• Xie Taofeng
• Wu Lingyan
• Liu Yang

Classifications

• G06F3/0446

  using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes · CPC title

• G06F3/0412 Primary

  Digitisers structurally integrated in a display · CPC title

• G06F2203/04103

  Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices · CPC title

• G06F2203/04112

  Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material · CPC title

• G06F2203/04111

  Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate · CPC title