Touch sensor and method of manufacturing the same

• US 10,642,392 B2
• Filed: 02/14/2018
• Issued: 05/05/2020
• Est. Priority Date: 02/16/2017
• Status: Active Grant

• Current Assignee: Dongwoo Fine-Chem Co., Ltd. (Sumitomo Chemical Company Ltd.)
• Original Assignee: Dongwoo Fine-Chem Co., Ltd. (Sumitomo Chemical Company Ltd.)
• Inventors: Yoon, Ju In, Lee, Jae Hyun, Choi, Yong-Seok
• Primary Examiner(s): Park, Sanghyuk
• Application Number:
  US15/896,393
• Publication Number:
  US 20180232090A1
• Time in Patent Office: 811 Days
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/042 by opto-electronic means

Abstract

A touch sensor includes a base film including a first region and a second region. First sensing electrode patterns are formed on the first region of the base film. The first sensing electrode pattern may consist of a transparent metal oxide. Second sensing electrode patterns are formed on the second region of the base film. The second sensing electrode pattern may include a multi-layered structure that includes a transparent metal oxide pattern and a metal pattern.

Claims

1. A touch sensor, comprising:

a base film including a first region and a second region;

first sensing electrode patterns on the first region of the base film, the first sensing electrode patterns consisting of a single layer of a transparent metal oxide; and

second sensing electrode patterns on the second region of the base film, the second sensing electrode patterns including a multi-layered structure that includes a transparent metal oxide pattern and a metal pattern,

wherein the first region has greater light transmittance than the second region, and the second region has higher touching sensitivity than the first region; and

each of the first sensing electrode patterns and the second sensing electrode patterns has first patterns and second patterns that are insulated from the first patterns, and the first patterns and the second patterns are arranged in directions crossing each other.

2. The touch sensor according to claim 1, wherein the first sensing electrode patterns have a sheet resistance the second sensing electrode patterns.

3. The touch sensor according to claim 1, wherein the second sensing electrode patterns include a first transparent metal oxide pattern, the metal pattern and a second transparent metal oxide pattern which are sequentially stacked.

4. The touch sensor according to claim 3, wherein the first transparent metal oxide pattern includes indium tin oxide (ITO), and the second transparent metal oxide pattern include indium zinc oxide (IZO).

5. The touch sensor according to claim 1, wherein the first sensing electrode patterns have a single-layered structure of indium tin oxide (ITO).

6. The touch sensor according to claim 1, further comprising bridge patterns electrically connecting neighboring ones of the first sensing electrode patterns to each other, and electrically connecting neighboring ones of the sensing electrode patterns to each other.

7. The touch sensor according to claim 6, wherein the bridge patterns include a metal, and the bridge patterns are disposed between the first sensing electrode patterns and the base film and between the second sensing electrode patterns and the base film.

8. The touch sensor according to claim 7, wherein the base film further includes a third region and a pad formed on the third region of the base film.

9. The touch sensor according to claim 8, wherein the pad includes a stack structure including a first conductive pattern and a second conductive pattern formed on the first conductive pattern, wherein the first conductive pattern includes a metal, and the second conductive pattern includes a transparent metal oxide.

10. The touch sensor according to claim 9, wherein the first conductive pattern includes the same metal included in the bridge pattern, and the second conductive pattern includes the same transparent metal oxide included in the first sensing electrode patterns.

11. The touch sensor according to claim 8, further comprising a passivation layer formed on the first region and the second region to cover the first sensing electrode pattern and the second sensing electrode pattern.

12. The touch sensor according to claim 11, wherein the passivation layer partially covers a portion of the base film on the third region such that the pad is exposed.

13. An image display device, comprising:

a window film including a plane portion and a bent portion; and

the touch sensor of claim 1 disposed under the window film,

wherein a portion of the touch sensor of the first region is located in the plane portion and a portion of the touch sensor of the second region is located in the bent portion.

14. A method of manufacturing a touch sensor, comprising:

preparing a base film including a first region and a second region;

forming a first transparent metal oxide layer on the base film;

forming a low resistance pattern on a portion of the first transparent metal oxide layer on the second region, the low resistance pattern having a resistance less than that of the first transparent metal oxide layer;

etching the first transparent metal oxide layer using the low resistance pattern as a mask to form a second sensing electrode pattern including the low resistance pattern on the second region; and

forming a first sensing electrode pattern consisting of a transparent metal oxide on a portion of the base film of the first region.

15. The method according to claim 14, wherein preparing the base film includes:

forming a separation layer on a carrier substrate; and

forming a protective layer on the separation layer.

16. The method according to claim 15, further comprising:

forming a passivation layer covering the first sensing electrode pattern and the second sensing electrode pattern; and

detaching the carrier substrate from the separation layer.

17. The method according to claim 14, wherein the base film further includes a third region,

wherein the method further comprises forming a pad on a portion of the base film of the third region.

18. The method according to claim 17, further comprising forming a second transparent metal oxide layer after forming the second sensing electrode pattern,

wherein the first sensing electrode pattern and the pad are formed simultaneously by etching the second transparent metal oxide layer.

19. The method according to claim 17, wherein the first sensing electrode pattern and the pad are formed simultaneously by etching the first transparent metal oxide layer.

20. The method according to claim 14, further comprising before forming the first transparent metal oxide layer:

forming bridge patterns on the base film by etching a metal layer; and

forming an insulation layer that includes contact holes partially exposing the bridge patterns,

wherein the first transparent metal oxide layer is formed on the insulation layer to at least partially fill the contact holes.