Touch sensing type liquid crystal display device including anti-static outer layer and method of fabricating the same

• US 9,218,080 B2
• Filed: 03/18/2011
• Issued: 12/22/2015
• Est. Priority Date: 03/19/2010
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Oh, Kum-Mi, An, Yong-Su, Nam, Kyoung-Jin, Lee, Han-Seok
• Primary Examiner(s): Ghebretinsae, Temesgh
• Assistant Examiner(s): LANDIS, LISA S
• Application Number:
  US13/050,990
• Publication Number:
  US 20110227850A1
• Time in Patent Office: 1,740 Days
• Field of Search: 345 30- 34, 345/38, 345 87-104, 345173-178
• US Class Current: 1/1
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/134372 for fringe field switching [FFS] where the common electrode is not patterned
• CPC Class Codes: G02F 2202/22 Antistatic materials or arrangements
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A touch sensing type liquid crystal display device includes an array substrate includes an array substrate including a first substrate, a common electrode, a pixel electrode, and a touch sensing unit; a color filter substrate including a second substrate and facing the array substrate; an anti-static layer on an outer side of the second substrate and including an inorganic material and conductive particles; and a liquid crystal layer between the first substrate and an inner side of the second substrate.

Claims

1. A touch sensing type liquid crystal display device, comprising:

a liquid crystal panel including a first substrate, a second substrate facing the first substrate, and a liquid crystal layer between the first and second substrates;

a pixel electrode and a common electrode on an inner side of the first substrate;

a color filter on an inner side of the second substrate;

an X direction sensing line on the common electrode and overlapping one of a plurality of gate lines, the X direction sensing line directly contacting the common electrode;

a Y direction sensing line on the common electrode and overlapping one of a plurality of data lines, the Y direction sensing line directly contacting the common electrode; and

an anti-static layer on an outer side of the second substrate and including a base layer of an inorganic material and a plurality of conductive particles in the base layer,

wherein a user'"'"'s touch is detected by a capacitor constituted by a user'"'"'s finger, the anti-static layer, and the common electrode,

wherein the anti-static layer is configured to discharge static electricity, and

wherein the common electrode, the X direction sensing line, and the Y direction sensing line form a touch sensing unit.

2. The device according to claim 1, wherein the anti-static layer has a sheet resistance of several tens of thousands to several hundreds of thousands ohms per square (Ω

/sq).

3. The device according to claim 1, further comprising:

an X direction sensing circuit at one end of the X direction sensing line; and

a Y direction sensing circuit at one end of the Y direction sensing line.

4. The device according to claim 3, wherein each touch sensing unit includes first to third regions, each of which includes at least one pixel region, and wherein the X direction sensing line is in the first and third regions, and the Y direction sensing line is in the second region.

5. The device according to claim 4, wherein the X direction sensing line in the first region is electrically connected to the X direction sensing line in the third region.

6. The device according to claim 5, wherein the touch sensing unit further includes a connection line in the second region for electrical connection of the X direction sensing line in the first region and the X direction sensing line in the third region.

7. The device according to claim 4, wherein the common electrode has an island shape in each of the first to third regions.

8. The device according to claim 1, wherein the array substrate further includes:

an interlayer insulating layer on the plurality of gate lines;

a plurality of pixel regions defined by the plurality of gate lines and the plurality of data lines, wherein the plurality of pixel regions each form first to third regions;

a thin film transistor in each pixel region and connected to one of the plurality of gate lines and one of the plurality of data lines;

a first passivation layer on the plurality of data lines and the thin film transistors, wherein the common electrode is on the first passivation layer and has an island shape in each of the first to the third regions; and

a second passivation layer over the common electrode, wherein the first and the second passivation layers have a drain contact hole exposing a portion of the thin film transistors,

wherein the pixel electrode is on the second passivation layer and contacts the portion of the thin film transistors through the drain contact hole.

9. The device according to claim 8, wherein the pixel electrode has at least one opening to generate a fringe field with the common electrode.

10. The device according to claim 8, wherein the touch sensing unit includes:

a connection line in the second region under the interlayer insulating layer;

a first and a second connection patterns on the second passivation layer,

wherein the second passivation layer has a first contact hole exposing an end of the X direction sensing line in the first region and a second contact hole exposing an end of the X direction sensing line in the third region, wherein the first and the second passivation layers have a drain contact hole exposing a portion of the thin film transistors, and the first and the second passivation layers and the interlayer insulating layer have third and fourth contact holes respectively exposing both ends of the connection line,

wherein one end of the first connection pattern contacts the X direction sensing line in the first region through the first contact hole, and the other end of the first connection pattern contacts one end of the connection line through the third contact hole,

wherein one end of the second connection pattern contacts the X direction sensing line in the third region through the second contact hole, and the other end of the second connection pattern contacts the other end of the connection line through the fourth contact hole, and

wherein the X direction sensing line is in the first and the third regions, and the Y direction sensing line is in the second region.

11. The device according to claim 8, wherein the color filter substrate further includes:

a black matrix corresponding to boundaries of each pixel region.

12. A method of fabricating a touch sensing type liquid crystal display device, comprising:

forming a gate line, a data line, a thin film transistor, a common electrode in each of a plurality of touch blocks, a pixel electrode, and a touch sensing unit including an X direction sensing line and a Y direction sensing line on a first substrate;

forming an anti-static layer on an outer side of a second substrate, the anti-static layer including a base layer of an inorganic material and a plurality of conductive particles in the base layer; and

attaching the first and the second substrates with a liquid crystal layer interposed between the first and the second substrates,

wherein a user'"'"'s touch is detected by a capacitor constituted by a user'"'"'s finger, the anti-static layer, and the common electrode,

wherein the anti-static layer is configured to discharge static electricity,

wherein the X direction sensing line is on and directly contacting the common electrode and overlaps one of a plurality of gate lines, and

wherein the Y direction sensing line is on and directly contacting the common electrode and overlaps one of a plurality of data lines.

13. The method according to claim 12, wherein the anti-static layer has a sheet resistance of several tens of thousands to several hundreds of thousands ohms per square (Ω

/sq).

14. The method according to claim 12, wherein the step of forming the anti-static layer is performed by a sputtering process with a target including an inorganic base material and the conductive particles.

15. The method according to claim 14, wherein the sputtering process is performed under a room temperature or a temperature above 300°

C.

16. The method according to claim 12, wherein the step of forming the touch sensing unit further includes:

forming a connection line at the same layer as the gate line;

and

forming first and second connection patterns at the same layer as the pixel electrode,

wherein one end of the first connection pattern is electrically connected to the X direction sensing line in a first region, and the other end of the first connection pattern is electrically connected to the connection line,

wherein one end of the second connection pattern is electrically connected to the X direction sensing line in a second region, and the other end of the second connection pattern is electrically connected to the connection line, and

wherein the X direction sensing line is in the first and the second regions, and the Y direction sensing line is in a third region between the first and the second regions.

17. A method of fabricating a touch sensing type liquid crystal display device, comprising:

forming a gate line, a data line, a thin film transistor, a common electrode, a pixel electrode, and a touch sensing unit including an X direction sensing line and a Y direction sensing line on a first substrate;

attaching a second substrate to the first substrate to form a liquid crystal panel, wherein the liquid crystal panel has a first thickness;

etching an outer side of each of the first and the second substrates such that the liquid crystal panel has a second thickness thinner than the first thickness; and

forming an anti-static layer on the outer side of the second substrate, the anti-static layer including a base layer of an inorganic material and a plurality of conductive particles in the base layer,

wherein the step of forming the anti-static layer is performed by a sputtering process with a target including an inorganic base material and the conductive particles, wherein the sputtering process is performed under a room temperature or a temperature below 100°

C.,

wherein a user'"'"'s touch is detected by a capacitor constituted by a user'"'"'s finger, the anti-static layer, and the common electrode,

wherein the anti-static layer is configured to discharge static electricity,

wherein the X direction sensing line is on and directly contacting the common electrode and overlaps one of a plurality of gate lines, and

wherein the Y direction sensing line is on and directly contacting the common electrode and overlaps one of a plurality of data lines.

18. The method according to claim 17, wherein the anti-static layer has a sheet resistance of several tens of thousands to several hundreds of thousands ohms per square (Ω

/sq).

19. The method according to claim 17, wherein the inorganic material includes silicon oxide or silicon nitride.

20. The method according to claim 17, wherein the conductive particles include aluminum or gallium.

21. The method according to claim 17, wherein the step of forming the touch sensing unit further includes:

forming a connection line at the same layer as the gate line;

and

forming first and second connection patterns at the same layer as the pixel electrode,

wherein one end of the first connection pattern is electrically connected to the X direction sensing line in the first region, and the other end of the first connection pattern is electrically connected to the connection line,

wherein one end of the second connection pattern is electrically connected to the X direction sensing line in the second region, and the other end of the second connection pattern is electrically connected to the connection line, and

wherein the X direction sensing line is in first and second regions, and the Y direction sensing line is in a third region between the first and second regions.