Liquid crystal display device and method for manufacturing the same

Abstract

Disclosed are an LCD device and a method of manufacturing the same, in which a passivation layer and a pixel electrode are simultaneously formed by a single mask process using a half tone mask, and thus, manufacturing efficiency increases, and a defective contact due to loss of the pixel electrode can be prevented in a pad area. The LCD device includes a pad part including a pad area and a contact area. The LCD device includes a pixel pad formed in the pad area, a pixel bar formed in the contact area, and a bridge layer contacting the pixel pad with the pixel bar. The bridge layer is formed as a single layer or multi layers, and formed of one or more of a transparent conductive material and an opaque conductive material.

Claims

1. A liquid crystal display (LCD) device, comprising: an active area with a plurality of pixels; an inactive area comprising a pad part including a pad area and a contact area; a first passivation layer in the pad area and the contact area, and having a first contact hole in the pad area; a pixel pad formed in the first contact hole; a pixel bar formed in the contact area and separated from the pixel pad; and a bridge on the first passivation layer in the contact area, the bridge extending to the first contact hole and connecting the pixel bar to the pixel pad; and a second passivation layer on the first passivation layer, and having a second contact hole in the pixel bar exposing a portion of the bridge on the first passivation layer and a third contact hole exposing another portion of the bridge in the first contact hole.

2. The LCD device of claim 1, wherein the pad part comprises a unit on-off pad part, a unit FPC pad/unit FPC shorting connection part, and a bump input dummy/bump output dummy part.

3. The LCD device of claim 1, further comprising a pixel electrode contacting the bridge via the third contact hole.

4. The LCD device of claim 3, wherein the bridge comprises a lower metal connected to the pixel pad in the first contact hole, and wherein the pixel electrode contacts the lower metal via the third contact hole.

5. The LCD device of claim 4, wherein the lower metal is disposed on the first passivation layer in the contact area.

6. The LCD device of claim 5, wherein the bridge further comprises a contact pattern on the second passivation layer and contacting the lower metal via the second contact hole.

7. The LCD device of claim 6, wherein the contact pattern extends to the pad area and contacts the lower metal via the third contact hole.

8. The LCD device of claim 1, further comprising a pixel electrode on the second passivation layer in the contact area, wherein the pixel electrode contacts the bridge via the second contact hole.

9. The LCD device of claim 8, wherein: the pixels include a common electrode, the bridge comprises a contact pattern on the first passivation layer in the contact area, the contact pattern extending to the first contact hole, and the contact pattern is formed of a same transparent conductive material on a same underlying layer as the common electrode.

10. The LCD device of claim 8, wherein the bridge comprises: a contact pattern on the first passivation layer in the contact area, the contact pattern extending to the first contact hole; and a lower metal on the contact pattern in the contact area.

11. The LCD device of claim 10, wherein the second contact hole exposes the lower metal, and wherein the pixel electrode contacts the lower metal via the second contact hole.

12. The LCD device of claim 1, wherein the second passivation layer has at least one other contact hole in the pixel bar in addition to the second contact hole to further expose the bridge.

13. The LCD device of claim 1, wherein the pixels include a transparent common electrode, and wherein the bridge comprises a same transparent conductive material on a same underlying layer as the common electrode.

14. The LCD device of claim 1, wherein the first contact hole has a larger area than the bridge in the first contact hole in plan view, and wherein the bridge has a larger area than the third contact hole in plan view.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings:

(2) FIG. 1 is a view illustrating a related art LCD device;

(3) FIG. 2 is a view illustrating a pixel structure of the related art LCD device;

(4) FIG. 3 is a view for describing limitations of a related art method of manufacturing an LCD device;

(5) FIG. 4 is a view for describing disconnection of a pixel bar that occurs in a pad part of the related art LCD device;

(6) FIG. 5 is a view for describing disconnection of a pixel bar that occurs in a pad part of the related art LCD device;

(7) FIG. 6 is a view illustrating a plurality of masks that are used in a schematic manufacturing method and process of a related art LCD device with integrated touch sensor;

(8) FIG. 7 is a view illustrating an LCD device according to an embodiment of the present invention;

(9) FIG. 8 is a view illustrating a pixel structure of an LCD device according to a first embodiment of the present invention;

(10) FIG. 9 is a view illustrating a pad part of an LCD device according to a first embodiment of the present invention;

(11) FIG. 10 is an enlarged view of a contact area of FIG. 9;

(12) FIGS. 11 to 15 are views illustrating a method of manufacturing an LCD device according to an embodiment of the present invention;

(13) FIG. 16 is a view illustrating a pixel structure of an LCD device according to a second embodiment of the present invention;

(14) FIG. 17 is a view illustrating a pad part of an LCD device according to a second embodiment of the present invention;

(15) FIG. 18 is an enlarged view of a contact area of the pad part of FIG. 17;

(16) FIG. 19 is a sectional view taken along line A1-A2 and line B1-B2 of FIG. 17;

(17) FIGS. 20 to 24 are views illustrating a method of manufacturing an LCD device according to an embodiment of the present invention; and

(18) FIG. 25 is a view illustrating a plurality of masks that are used in a schematic manufacturing method and process of an LCD device with integrated touch sensor.

DETAILED DESCRIPTION OF THE INVENTION

(19) Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

(20) Hereinafter, an LCD device with integrated touch sensor and a method of manufacturing the same according to embodiments of the present invention will be described with reference to the accompanying drawings.

(21) In description of embodiments of the present invention, when a structure (for example, an electrode, a line, a wiring, a layer, or a contact) is described as being formed at an upper portion/lower portion of another structure or on/under the other structure, this description should be construed as including a case where the structures contact each other and moreover a case where a third structure is disposed therebetween.

(22) Furthermore, terms “upper portion/lower portion” and “on/under” are for describing the structure and manufacturing method of the present invention with reference to the drawings. Therefore, the terms “upper portion/lower portion” and “on/under” may differ in structure during a manufacturing process and after manufacturing is completed.

(23) LCD devices have been variously developed in a twisted nematci (TN) mode, a vertical alignment (VA) mode, an in-plane switching (IPS) mode, and a fringe field switching (FFS) mode according to a scheme of adjusting the alignment of liquid crystal.

(24) In the IPS mode and the FFS mode among the modes, a plurality of pixel electrodes and common electrode are arranged on a lower substrate, and thus, the alignment of liquid crystal is adjusted by electric fields between the pixel electrodes and the common electrodes.

(25) In the IPS mode, particularly, the pixel electrodes and the common electrodes are alternately arranged in parallel, and thus, lateral electric fields are respectively generated between the pixel electrodes and the common electrodes, thereby adjusting the alignment of liquid crystal.

(26) In the IPS mode, however, the alignment of liquid crystal is not adjusted in a portion on the pixel electrodes and common electrodes, and thus, light transmittance is reduced in a corresponding area.

(27) To overcome the limitation of the IPS mode, the FFS mode has been proposed. In the FFS mode, a plurality of pixel electrodes and common electrodes are formed apart from each other with an insulating layer therebetween.

(28) In this case, the one electrodes of the pixel electrodes and common electrodes are formed in a plate shape or a pattern, and the other electrodes are formed in a finger shape, thereby adjusting the alignment of liquid crystal with fringe fields generated between the pixel electrodes and common electrodes.

(29) An LCD device with integrated touch sensor (screen) according to embodiments of the present invention includes a liquid crystal panel, a backlight unit that supplies light to the liquid crystal panel, and a driving circuit part. Here, a liquid crystal panel is formed in an in-cell touch type in which a touch sensor for detecting a position touched by a user is built in the liquid crystal panel.

(30) The driving circuit part includes a timing controller (T-con), a data driver (D-IC), a gate driver (G-IC), a sensing driver, a backlight driver, and a power supply that supplies a driving source voltage to the drivers.

(31) Here, all or some of the driving circuit part may be formed in a chip on glass (COG) type or a chip on film (chip on flexible printed circuit, COF), on a liquid crystal panel.

(32) FIG. 7 is a view illustrating an LCD device according to an embodiment of the present invention. FIG. 8 is a view illustrating a pixel structure of an LCD device according to a first embodiment of the present invention;

(33) In FIGS. 7 and 8, the structure of a thin film transistor (TFT) array substrate (lower substrate) is illustrated in the FFS mode. In FIGS. 7 and 8, a touch sensor is illustrated as being internalized in an in-cell touch type in the TFT array substrate.

(34) In FIGS. 7 and 8, a color filter array substrate (upper substrate), a liquid crystal layer, a backlight unit, and a driving circuit part are not illustrated.

(35) Referring to FIG. 7, an active area 100 displaying an image is formed at a TFT array substrate, and an inactive area is formed at an outer portion of the active area 100. A plurality of pixels are formed in the active area 100. Furthermore, a plurality of pad parts 230, 240 and 250 are formed in the inactive area 200.

(36) The plurality of pad parts 230, 240 and 250 formed in the inactive area 200 include a unit on-off pad part 230, a unit FPC pad/unit FPC shorting connection part 240, and a bump input dummy/bump output dummy part 250.

(37) In FIG. 7, the pad parts 230, 240 and 250 are illustrated as being formed at an outer portion of an upper end of a panel, but may be formed at an outer portion of a left/right side of the panel and an outer portion of a lower end of the panel.

(38) A plurality of pixels formed in the active area are defined by respective intersections between a plurality of data lines (not shown) and gate lines (not shown). A TFT is formed in each of a plurality of areas in which the data lines intersect the gate lines.

(39) The plurality of pixels are formed at the TFT array substrate, and defined by respective intersections between the data lines (not shown) and the gate lines (not shown).

(40) A TFT is formed in each of a plurality of areas in which the data lines intersect the gate lines. Also, each of the pixels includes a common electrode and a pixel electrode.

(41) Referring to FIG. 8, the TFT array substrate includes a glass substrate 110, a light shield 120, a buffer layer 122, a gate insulator 136, a data contact 145, a inter-layer dielectric (ILD) 140, a first passivation layer 150, a common electrode 160, a touch sensing line 170, a second passivation layer 180, a pixel electrode 190, and a TFT that includes an active 130, a source 132, a drain 134, and a gate 138. Here, the TFT includes a lightly doped drain (LDD) 133.

(42) In an upper portion of the glass substrate 110, the light shield 120 is formed in a TFT area, and the buffer layer 122 is formed to cover the light shield 120. The light shield 120 may be formed of Mo or Al, and have a thickness of 500 Å.

(43) The buffer layer 122 may be formed of an inorganic material, for example, SiO.sub.2 or SiNx, and have a thickness of 2,000 Å to 3,000 Å.

(44) The active 130, source 132, and drain 134 of the TFT are formed in an area overlapping the light shield 120, on the buffer layer 122 in the TFT area.

(45) Here, the active 130 may be formed of poly silicon (P-Si), and have a thickness of 500 Å. The LDD 133, the source 132, and the drain 134 may be formed by doping P-type impurities or N-type impurities on a semiconductor layer.

(46) The gate insulator 136 is formed to cover the active 130, the source 132, and the drain 134 on the buffer layer 122. In this case, the gate insulator 136 may be formed of SiO.sub.2, and have a thickness of 1,300 Å.

(47) The gate insulator 136 may be formed by depositing tetra ethyl ortho silicate (TEOS) or middle temperature oxide (MTO) in a chemical vapor deposition (CVD) process.

(48) In an upper portion of the gate insulator 136, the light shield 120 is formed in an area overlapping the active 130. In this case, the gate 138 may be formed of Al or Mo, and have a thickness of 3,000 Å.

(49) In this way, the gate 138 and the active 130, source 132, and drain 134 are formed with the gate insulator 136 therebetween, thereby forming the TFT.

(50) The inter-layer dielectric 140 is formed to cover the gate 138, on the gate insulator 136.

(51) In this case, the inter-layer dielectric 140 may be formed of SiO.sub.2 or SiNx, and have a thickness of 6,000 Å. As another example, the inter-layer dielectric 140 may be formed in a structure in which SiO.sub.2 (3,000 Å) and SiNx (3,000 Å) are stacked.

(52) A portion of the gate insulator 136 and a portion of the inter-layer dielectric 140 are etched to expose a top of the drain 134, and the data contact 145 is formed at a portion in which the gate insulator 136 and the inter-layer dielectric 140 are etched. The data contact 145 contacts the drain 134.

(53) The data contact 145 contacts the drain 134 and the pixel electrode 190. In this case, the data contact 145 may be formed to have a thickness of 6,000 Å, and formed in a structure in which Mo, Al, and Mo are stacked.

(54) The first passivation layer (PAS1) 150 is formed to cover the data contact 145, on the inter-layer dielectric 140. Here, the first passivation layer 150 is formed of photo acryl, and has a thickness of 3 um.

(55) The common electrode 160 is formed on the first passivation layer 150, in the pixel area.

(56) The common electrode 160 may be formed of a transparent conductive material, such as indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), to have a thickness of 500 Å.

(57) The touch sensing line 170 is formed on the common electrode 160. The conductive line 170 is formed to cross the plurality of pixels, and connects the common electrodes 160 of adjacent pixels. Therefore, the common electrode 160 acts as a touch sensing electrode during a non-display period.

(58) Here, the touch sensing line 170 may be formed of Mo or Al, and have a thickness of 1,500 Å to 2,000 Å. The touch sensing line 170 may be formed in a structure in which Mo, Al, and Mo are stacked.

(59) The touch sensing line 170 connects the common electrodes 160 of adjacent pixels to form a touch block. In this case, the touch block includes a touch row block for detecting a touch position in an X-axis direction, and a touch column block for detecting a touch position in a Y-axis direction.

(60) The touch sensor detects X-axis and Y-axis coordinates for detecting a position touched by a user. Therefore, the touch row block and the touch column block are required to be separated from each other without contact therebetween.

(61) To this end, the touch sensing line 170 in the touch column block is connected in the Y-axis direction by using a conductive line that is formed to overlap the data line of the TFT array substrate. Therefore, the touch sensing line 170 in the touch column block enables the detection of a position touches by a user in the Y-axis direction.

(62) The touch sensing line 170 in the touch row block avoids contact with the touch column block by using a bride line that is formed simultaneously with a gate line formed on the TFT array substrate. The touch sensing line 170 in the touch row block enables the detection of a position touches by a user in the X-axis direction. For example, the bridge line disposed in a central portion of the pixel to block disclination of the multi-domain pixel region, the bridge line being parallel with the gate line.

(63) As described above, the touch row block and the touch column block are separated from each other, thereby enabling the detection of a position touched by a user in the X-axis direction and the Y-axis direction.

(64) A second passivation layer 180 is formed to cover the common electrode 160 and the touch sensing line 170, on the first passivation layer 150. Here, the second passivation layer 180 may be formed of SiO.sub.2 or SiNx, and have a thickness of 2,000 Å to 3,000 Å.

(65) A first contact hole 155 is formed in an area overlapping the data contact 145, in the first passivation layer 150.

(66) The second passivation layer 180 is etched to form a second contact hole 185, on the first contact hole 155.

(67) The pixel electrode 190 is formed in a finger shape in the pixel area, on the second passivation layer 180. The pixel electrode 190 is formed in the first and second contact holes 155 and 185, and contacts the data contact 145. Through such a contact structure, the drain 134 of the TFT contacts the pixel electrode 190 via the data contact 145.

(68) In this case, the pixel electrode 190 may be formed of a transparent conductive material, such as ITO, IZO, or ITZO, to have a thickness of 500 Å.

(69) The second passivation layer 180 and the pixel electrode 190 may be simultaneously formed by a single mask process by using one half tone mask (HTM).

(70) The LCD device according to an embodiment of the present invention adjusts the transmittance of light, which passes through a liquid crystal layer, with data voltages applied to the respective pixel electrodes of the pixels and a common voltage applied to the common electrodes during a display period, thereby displaying an image realized with image signals.

(71) Furthermore, the LCD device drives the respective common electrodes 160 of the pixels, connected by the touch sensing line 170, as touch sensing electrodes during the non-display period, thereby sensing the change in a capacitance (Ctc) due to a user's touch. The LCD device compares a capacitance generated by the user's touch and a reference capacitance to detect a touch position (TS).

(72) FIG. 9 is a view illustrating a pad part of an LCD device according to a first embodiment of the present invention. FIG. 10 is an enlarged view of a contact area of FIG. 9.

(73) In FIGS. 9 and 10, the unit on-off pad part 230 among the pad parts 230, 240 and 250 is illustrated.

(74) Referring to FIGS. 9 and 10, the unit on-off pad part 230 among the pad parts 230, 240 and 250 includes a plurality of pixel pads 232 and pixel bars (pixel lines) 234.

(75) The unit on-off pad part 230 formed at an outer portion of the panel is formed through a manufacturing process of forming the pixels. At this point, the first contact hole 155 is formed by broadly etching the first passivation layer (PAS1) 150. The unit on-off pad part 230 has a structure in which the pixel pads and the second contact holes 185 of the second passivation layer 180 are arranged in the first contact hole 155.

(76) The connection of the pixel bar 234 is made using the first contact hole 155 portion. Therefore, the pixel pads 232 and the second contact holes are arranged in the first contact hole 155.

(77) Moreover, in the unit on-off pad part 230, a lower metal 270 and the pixel electrode 190 are formed inside the first contact hole 155.

(78) Here, the lower metal 270 of the unit on-off pad part 230 may be formed of metal that is used when forming the touch sensing line formed in the pixel area. As another example, the lower metal 270 of the unit on-off pad part 230 may be formed of a transparent conductive material that is used when forming the common electrode formed in the pixel area.

(79) The unit on-off pad part 230 is formed for a contact instead of an electrode to which a pixel voltage for image display is supplied. The pixel electrode 190 of the unit on-off pad part 230 is formed of the same material as that of the pixel electrode in the pixel area when forming the pixel electrode.

(80) The pixel bar 234 and the pixel pad 232 are formed apart from each other, and thus are not directly connected. The pixel bar 234 and the pixel pad 232 are connected through the lower metal 270 and the contact pattern 260.

(81) To this end, the second contact hole 185 is formed in the second passivation layer 180 formed on the pixel bar 234. A contact pattern 260 is formed to contact the pixel bar 234, in the second contact hole 185. Furthermore, the contact pattern 260 is formed to contact the lower metal 270, in the first contact hole 155.

(82) In this way, the pixel bar 234 and the pixel pad 232 are connected using the contact pattern 260.

(83) Here, the contact pattern 260 is formed of a transparent conductive material, on the same layer as that of the common electrode 160 in the pixel area. A contact between the pixel bar 234 and the pixel pad 232 is formed by connecting the contact pattern 260 to the lower metal 270 connected to the pixel pad 232.

(84) The pixel bar 234 is formed to have a width of 20 um and a length of 36 um. The pixel bar 234 is formed to be separated by a distance of 5 um from the first contact hole 155 so as not to overlap the first contact hole 155.

(85) The second contact hole 185 formed on the pixel bar 234 may be formed in a 6 um×6 um size.

(86) The second contact hole 185 is formed in the first contact hole 155 inside the unit on-off pad part 230. In this case, the second contact hole 185 is formed to have a size similar to that of the lower metal 270. One side of the lower metal 270 is formed to have a size less by 10 um than that of the second contact hole 185, such that a contact between the lower metal 270 and the contact pattern 260 is smoothly made.

(87) Here, to prevent the contact of the pixel bar 234 from being broken at a boundary surface of the first contact hole 155, the lower metal 270 is used as a bridge for a contact between the pixel bar 234 and the pixel pad 232. Comparing with the related art, the length of the lower metal 270 of the present invention is expanded, and thus the lower metal 270 contacts the pixel bar 234 with the pixel pad 232.

(88) A contact area of the pixel bar 234 uses a clear area in a manufacturing process. In this case, the clear area is formed to have a size less than that of the lower metal 270. When forming the second contact 185 by etching the second passivation layer 180, the lower metal 270 act as an etch stop.

(89) Comparison between relative sizes of respective elements is as follows. The clear area of the first passivation layer is the greatest size, and the lower metal 270 has the second greatest size. The pixel electrode 190 has the smallest size. The pixel electrode 190 and the clear area of the second passivation layer 180 have the same size. That is, the clear area of the first passivation layer (PAS1)>the lower metal>the pixel electrode=the clear area of the second passivation layer (PAS2).

(90) Even in the unit FPC pad/unit FPC shorting connection part 240 and the bump input dummy/bump output dummy part 250, identically to the unit on-off pad part 230, contacts between pad patterns and a signal line (shorting bar) may be made using the lower metal 270 and the contact pattern 260 as a bridge.

(91) In the pad part of the LCD device (having the above-described structure) according to an embodiment of the present invention, the second contact hole 185 is formed in the pixel bar 234, and the pixel bar 234 may be connected to the pixel pad 232 in the pad area by using the lower metal 270 and the contact pattern 260 as a bridge. Therefore, the second passivation layer 180 and the pixel electrode 190 can be simultaneously formed using the half tone mask, and a defective contact can be prevented in the pad area.

(92) FIGS. 11 to 15 are views illustrating a method of manufacturing an LCD device according to an embodiment of the present invention. Here, FIGS. 11 to 15 illustrate a manufacturing process with respect to a sectional surface along line A1-A2 and line B1-B2 of FIG. 9. In FIGS. 11 to 15, a manufacturing method of forming a pixel in the active area is not illustrated.

(93) Hereinafter, the method of manufacturing the LCD device according to an embodiment of the present invention will be described with reference to FIGS. 11 to 15. A sectional view taken along line A1-A2 illustrates a portion corresponding to one pixel pad in the pad area. A sectional view taken along line B1-B2 illustrates a portion corresponding to one pixel pad in the pad area.

(94) Referring to FIG. 11, the first passivation layer (PAS1) 150 is formed in a pad area and a contact area. Subsequently, a clear area is formed by an etching process and a photolithography process using a half tone mask.

(95) The first contact hole 155 is formed through the clear area of the first passivation layer (PAS1) 150. Here, the first passivation layer 150 may be formed of photo acryl, and have a thickness of 3 um.

(96) Subsequently, the lower metal 270 is formed in the clear area of the contact area and the pad area. In this case, the lower metal 270 formed in the contact area is expanded in size, and thus formed on the first passivation layer 150 in a normal area as well as the clear area.

(97) The lower metal 270 of the unit on-off pad part 230 may be formed of at least one of the transparent conductive material of the common electrode and the metal of the touch sensing line formed in the pixel area.

(98) Here, in a subsequent process, the lower metal 270 acts as an etch stop of the second contact hole 185 that is formed by etching the second passivation layer 180.

(99) Subsequently, referring to FIG. 12, the second passivation layer (PAS2) 180 is formed to cover the first passivation layer 150 and the lower metal 270. Here, the second passivation layer 180 may be formed of SiO.sub.2 or SiNx, and have a thickness of 2,000 Å to 3,000 Å.

(100) Subsequently, referring to FIG. 13, a photoresist 195 is coated on the second passivation layer 180, and then, the etching process and the photolithography process using the half tone mask are performed.

(101) In the pad area, an area overlapping the lower metal 270, namely, the photoresist 195 on the first contact hole 155 is removed, thereby forming a clear area. In this case, the clear area is formed to have a size less than that of the lower metal 270.

(102) In the contact area, the photoresist 195 on the first contact hole 155 is removed, thereby forming a clear area.

(103) In the photoresist 195 in an area overlapping the normal area of the first passivation layer 150, a portion overlapping the lower metal 270 is removed to form the clear area, and the other portion is formed as a half tone area.

(104) A top of the second passivation layer 180 is exposed by the clear areas that are respectively formed in the pad area and the contact area.

(105) Subsequently, referring to FIG. 14, the second passivation layer 180 exposed by the clear area is removed by performing an ashing process, thereby exposing the lower metal 270.

(106) Specifically, the second passivation layer 180 in the clear area is removed in the pad area, and thus, the second contact hole 185 is formed. The lower metal 270 is exposed by the second contact hole 185.

(107) Moreover, the second passivation layer 180 in the clear area is removed in the contact area, and thus, the second contact hole 185 is formed. In this case, as illustrated in FIGS. 9 and 10, the second contact hole 185 formed in the contact area is formed on the pixel bar 234 to expose the pixel bar 234.

(108) The second contact hole 185 formed on the pixel bar 234 is formed to have a 6 um×6 um size.

(109) The first contact hole 155 and the second contact hole 185 are formed using a clear area of a half tone mask.

(110) Subsequently, referring to FIG. 15, the pixel electrode 190 is formed of a transparent conductive material such as ITO, in the pad area.

(111) Moreover, the contact pattern 260 is formed of a transparent conductive material such as ITO, in an outer portion of the pad area and the contact area.

(112) Here, the pixel bar 234 in the contact area and the pixel pad 232 in the pad area are formed apart from each other, and thus are not directly connected. The pixel bar 234 in the contact area and the pixel pad 232 in the pad area are connected through the lower metal 270 and the contact pattern 260.

(113) As described above, the second contact hole 185 is formed at the second passivation layer 180 formed on the pixel bar 234, and the pixel bar 234 and the pixel pad 232 are connected using the contact pattern 260 as a bridge.

(114) The contact pattern 260 is formed of a transparent conductive material, on the same layer as that of the common electrode 160 in the pixel area. The contact pattern 260 is connected to the lower metal 270 connected to the pixel pad 232. Therefore, the pixel bar 234 contacts the pixel pad 232.

(115) The pixel bar 234 is formed to have a width of 20 um and a length of 36 um. The pixel bar 234 is formed to be separated by a distance of 5 um from the first contact hole 155 so as not to overlap the first contact hole 155.

(116) The second contact hole 185 is formed to have a size similar to that of the lower metal 270. One side of the lower metal 270 is formed to have a size less by 10 um than that of the second contact hole 185, such that a contact between the lower metal 270 and the contact pattern 260 is smoothly made.

(117) To prevent the contact of the pixel bar 234 from being broken at a boundary surface of the first contact hole 155, the lower metal 270 is used as a bridge for a contact between the pixel bar 234 and the pixel pad 232.

(118) Comparing with the related art, the length of the lower metal 270 of the present invention is expanded, and thus the lower metal 270 contacts the pixel bar 234 with the pixel pad 232.

(119) The lower metal 270 that acts as a bridge for contact of the pixel bar 234 may be expanded in length to a lower portion of the pixel bar 234. In this case, the length of the lower metal 270 may be expanded using both the metal of a conductive line and the transparent conductive material of the common electrode. As another example, the length of the lower metal 270 may be expanded using only one of the metal of the conductive line and the transparent conductive material of the common electrode.

(120) Comparison between relative sizes of respective elements is as follows. The clear area of the first passivation layer is the greatest size, and the lower metal 270 has the second greatest size. The pixel electrode 190 has the smallest size.

(121) The pixel electrode 190 and the clear area of the second passivation layer 180 have the same size. That is, the clear area of the first passivation layer (PAS1)>the lower metal>the pixel electrode=the clear area of the second passivation layer (PAS2).

(122) According to another embodiment of the present invention, even in the unit FPC pad/unit FPC shorting connection part 240 and the bump input dummy/bump output dummy part 250, identically to the unit on-off pad part 230, contacts between pad patterns and a signal line (shorting bar) may be made using the lower metal 270 and the contact pattern 260 as a bridge.

(123) The sizes of the second contact hole 185 and pixel pad 232 in the second passivation layer 185 formed in the pad area may be changed, in which case the sizes are required to be sizes in which a test is capable of being performed with a probe tip.

(124) In the LCD device and the method of manufacturing the same according to the first embodiment of the present invention, the second passivation layer 180 and the pixel electrode 190 are simultaneously formed by the single mask process using the half tone mask, and thus, manufacturing efficiency increases.

(125) Moreover, in forming the pixel electrode 190, the present invention can prevent disconnection of the pixel bar 234, caused by loss of the pixel electrode 190 due to the lift-off process, in the pad area. Accordingly, the present invention can enhance the contact performance of the pixel bar 234 in the pad area.

(126) FIG. 16 is a view illustrating a pixel structure of an LCD device according to a second embodiment of the present invention. In FIG. 16, a touch sensor is illustrated as being internalized in an in-cell touch type in the TFT array substrate. In FIG. 16, a color filter array substrate (upper substrate), a liquid crystal layer, a backlight unit, and a driving circuit part are not illustrated. The pixel structure of FIG. 8 is similar to that of FIG. 16, and thus, a detailed description on the same element is not provided.

(127) Referring to FIG. 16, a TFT array substrate includes a glass substrate 110, a light shield 120, a buffer layer 122, a gate insulator 136, a data contact 145, a inter-layer dielectric (ILD) 140, a first passivation layer 150, a common electrode 160, a touch sensing line 170, a first contact line 160a, a second contact line 170a, a second passivation layer 180, a pixel electrode 190, and a TFT that includes an active 130, a source 132, an LDD 133, a drain 134, and a gate 138.

(128) A portion of the gate insulator 136 and a portion of the inter-layer dielectric 140 are etched to expose a top of the drain 134. The data contact 145 is formed at a portion in which the gate insulator 136 and the inter-layer dielectric 140 are etched.

(129) The data contact 145 contacts the drain 134 and the pixel electrode 190. The first passivation layer (PAS1) 150 is formed to cover the data contact 145, on the inter-layer dielectric 140.

(130) The common electrode 160 is formed on the first passivation layer 150, in a pixel area.

(131) The touch sensing line 170 is formed on the common electrode 160 to cross a plurality of pixels, and connects the common electrodes 160 of adjacent pixels. Therefore, the common electrode 160 acts as a touch sensing electrode during a non-display period.

(132) The first and second contact lines 160a and 170a are formed on the data contact 145. The first and second passivation layers 150 and 180 are etched to expose a top of the data contact 145, thereby forming a contact hole. The first and second contact lines 160a and 170a are formed inside the contact hole.

(133) Here, the first contact line 160a is formed of the same material as that of the common electrode 160 simultaneously with the common electrode 160 during a manufacturing process. The second contact line 170a is formed of the same material as that of the touch sensing line 170 simultaneously with the touch sensing line 170 during the manufacturing process.

(134) The first and second contact lines 160a and 170a are formed insularly, and thus, a signal and a voltage are not supplied thereto. That is, the first and second contact lines 160a and 170a act as a via between the data contact 145 and the pixel electrode 190.

(135) A second passivation layer 180 is formed to cover the common electrode 160 and the touch sensing line 170, on the first passivation layer 150.

(136) A first contact hole 155 is formed in an area overlapping the data contact 145, in the first passivation layer 150.

(137) The second passivation layer 180 is etched to form a second contact hole 185, on the first contact hole 155.

(138) The pixel electrode 190 is formed in a finger shape in the pixel area, on the second passivation layer 180. The pixel electrode 190 is formed in the first and second contact holes 155 and 185, and contacts the data contact 145.

(139) The second passivation layer 180 and the pixel electrode 190 may be simultaneously formed by a single mask process by using one half tone mask (HTM).

(140) FIG. 17 is a view illustrating a pad part of an LCD device according to a second embodiment of the present invention. FIG. 18 is an enlarged view of a contact area of the pad part of FIG. 17. FIG. 19 is a sectional view taken along line A1-A2 and line B1-B2 of FIG. 17.

(141) In FIGS. 17 to 19, a unit FPC pad/unit FPC shorting connection part 240 among a plurality of pad parts 230, 240 and 250 is illustrated.

(142) Referring to FIGS. 17 to 19, the unit FPC pad/unit FPC shorting connection part 240 among the pad parts 230, 240 and 250 includes a plurality of pads 242, a plurality of pixel bars (pixel lines) 244, and a power line 246.

(143) The unit FPC pad/unit FPC shorting connection part 240 includes a pad area in which the pads 242 are formed, and a contact area in which the pixel bar 244 contacts the pad 242.

(144) The unit FPC pad/unit FPC shorting connection part 240 is formed by a manufacturing process of forming a plurality of pixels. Here, the unit FPC pad/unit FPC shorting connection part 240 has a structure in which a pad pattern for supplying a signal to a pixel are arranged in each of the pads 242.

(145) Moreover, a lower metal 270 and the pixel electrode 190 are formed in the contact area of the unit FPC pad/unit FPC shorting connection part 240. In this case, the lower metal 270 and pixel electrode 190 formed in the contact area are formed apart from the first contact hole 155.

(146) The pixel bar 244 and pad 242 of the unit FPC pad/unit FPC shorting connection part 240 are formed to be separated from each other, and thus are not directly connected. The pixel bar 244 and the pad 242 are connected through a bridge layer 280 that is configured with the contact pattern 260 and the lower metal 270.

(147) The bridge layer 280 may be configured with the contact pattern 260 and the lower metal 270.

(148) The contact pattern 260 and the common electrode 160 in the pixel area may be formed on the same layer. The contact pattern 260 is formed of a transparent conductive material (ITO) which is the material of the common electrode 160.

(149) The lower metal 270 may be formed using the metal of the touch sensing line 170 formed in the pixel area. When forming the touch sensing line 170, the lower metal 270 is formed of the same material as that of the touch sensing line 170.

(150) To connect the pixel bar 244 and the pad 242, the second contact hole 185 is formed in the second passivation layer 180 on the pixel bar 244. The pixel electrode 190 is formed on the second passivation layer 180 and in the second contact hole 185. The contact pattern 260 is formed in the first contact hole 155. The lower metal 270 is formed on the contact pattern 260, in an area in which the second contact hole 185 is formed. That is, the contact pattern 260 and the lower metal 270 are stacked in an area in which the second contact hole 185 is formed. In this way, the pixel bar 244 and the pad 242 are connected with the bridge layer 280 that is configured with the contact pattern 260 and the lower metal 270.

(151) When simultaneously forming the second passivation layer 180 and the pixel electrode 190 in an etching process, a lift-off process, and a photolithography process using a half tone mask, the pixel electrode 190 may be lost in the contact area. However, even when the pixel electrode 190 is lost in the contact area, a contact is not disconnected because the pixel bar 244 and the pad 242 are connected with the bridge layer 280.

(152) Here, the pixel bars 234 are formed to be separated by a distance of 10 um to 20 um from each other so as not to overlap the first contact hole 155.

(153) The second contact hole 185 formed on the pixel bar 234 may be formed in a 6 um×6 um size.

(154) The second contact hole 185, as illustrated in FIG. 17, may be formed as one on one pixel bar 244, but is not limited thereto. To more enhance the contact performance of the pixel bar 244, as illustrated in FIG. 18, a plurality of the second contact holes 185 may be formed in one pixel bar 244.

(155) A contact area of the pixel bar 234 is formed using a clear area in a manufacturing process. In this case, the clear area is formed to have a size less than that of the lower metal 270. When forming the second contact 185 by etching the second passivation layer 180, the lower metal 270 act as an etch stop.

(156) As illustrated in FIG. 19, the second contact hole 185 formed in the contact area is formed to have a size less than that of the lower metal 270. As an example, the second contact hole 185 is formed to have a size less by 10 um than that of one side of the lower metal 270.

(157) In addition to the unit FPC pad/unit FPC shorting connection part 240, the unit on-off pad part 230 and the bump input dummy/bump output dummy part 250 may also connect the pad 242 and the pixel bar 244 by using the above-described bridge layer 280.

(158) In the pad part of the LCD device (having the above-described structure) according to an embodiment of the present invention, the second contact hole 185 is formed in the pixel bar 244, and the pixel bar 234 may be connected to the pixel pad 232 in the pad area by using the bridge layer 280 configured with the lower metal 270 and the contact pattern 260. Therefore, the second passivation layer 180 and the pixel electrode 190 can be simultaneously formed using the half tone mask, and the defective contact of the pixel bar 244 can be prevented in the pad area.

(159) FIGS. 20 to 24 are views illustrating a method of manufacturing an LCD device according to an embodiment of the present invention.

(160) FIGS. 20 to 24 illustrate a manufacturing process with respect to a sectional surface along line A1-A2 and line B1-B2 of FIG. 17. In FIGS. 20 to 24, a manufacturing method of forming a pixel in the active area is not illustrated.

(161) Hereinafter, the method of manufacturing the LCD device according to an embodiment of the present invention will be described with reference to FIGS. 20 to 24. A sectional view taken along line A1-A2 illustrates a portion corresponding to one pixel pad in the pad area. A sectional view taken along line B1-B2 illustrates a portion corresponding to one pixel pad in the pad area.

(162) Referring to FIG. 20, the first passivation layer (PAS1) 150 is formed in a pad area and a contact area.

(163) Subsequently, in the contact area, a portion of the first passivation layer (PAS1) 150 is etched by performing an etching process and a photolithography process using a half tone mask. The etched portion of the first passivation layer 150 becomes the first contact hole 155. The first passivation layer 150 may be formed using the clear area of the half tone mask.

(164) In this case, the first passivation layer 150 may be formed of photo acryl, and have a thickness of 3 um.

(165) Subsequently, the bridge layer 280 is formed by sequentially forming the contact pattern 260 and the lower metal 270 in the pad area and the contact area.

(166) In this case, in the contact area, the contact pattern 260 is formed on the first passivation layer 150 and in the first contact hole 155 area. The lower metal 270 is formed only on the first passivation layer 150

(167) Here, in a subsequent process, the lower metal 270 acts as an etch stop of the second contact hole 185 that is formed by etching the second passivation layer 180.

(168) Subsequently, referring to FIG. 21, the second passivation layer (PAS2) 180 is formed on the first passivation layer 150 and in the first contact hole 155 area. Here, the bridge layer 280 is covered by the second passivation layer 180. The second passivation layer 180 may be formed of SiO.sub.2 or SiNx, and have a thickness of 2,000 Å to 3,000 Å.

(169) Subsequently, referring to FIG. 22, a photoresist 195 is coated on the second passivation layer 180, and then, the etching process and the photolithography process using the half tone mask are performed.

(170) In the pad area, a portion of the photoresist 195 partially overlapping the bridge layer 280 is removed, thereby forming a clear area. In this case, the clear area is formed to have a size less than that of the lower metal 270.

(171) In the contact area, a portion of the photoresist 195 partially overlapping the bridge layer 280 is removed, thereby forming a clear area.

(172) A portion of the photoresist 195 that does not overlap the bridge layer 280 forms a half tone area or a normal area.

(173) A top of the second passivation layer 180 is exposed by the clear areas that are respectively formed in the pad area and the contact area.

(174) Subsequently, referring to FIG. 23, the second passivation layer 180 exposed by the clear area is removed by performing an ashing process, thereby exposing the bridge layer 280.

(175) Specifically, the second passivation layer 180 in the clear area is removed in the pad area, and thus, the second contact hole 185 is formed. The bridge layer 280 is exposed by the second contact hole 185.

(176) Moreover, the second passivation layer 180 in the clear area is removed in the contact area, and thus, the second contact hole 185 is formed. In this case, the second contact hole 185 formed in the contact area is formed on the pixel bar 244 to expose the pixel bar 244.

(177) The second contact hole 185 formed on the pixel bar 234 is formed to have a 6 um×6 um size.

(178) The second contact hole 185, as illustrated in FIG. 17, may be formed as one on one pixel bar 244, but is not limited thereto. To more enhance the contact performance of the pixel bar 244, as illustrated in FIG. 18, a plurality of the second contact holes 185 may be formed in one pixel bar 244.

(179) The first contact hole 155 and the second contact hole 185 are formed using a clear area of a half tone mask.

(180) Subsequently, referring to FIG. 24, the pixel electrode 190 is formed of a transparent conductive material such as ITO, in the pad area.

(181) Moreover, the pixel electrode 190 is formed of a transparent conductive material such as ITO, in an outer portion of the pad area and the contact area.

(182) Here, the pixel bar 244 in the contact area and the pad 242 in the pad area are formed apart from each other, and thus are not directly connected. The pixel bar 234 in the contact area and the pixel pad 232 in the pad area are connected through the bridge layer 280.

(183) Accordingly, by performing the lift-off process for simultaneously forming the second passivation layer 180 and the pixel electrode 190, a contact between the pad 242 and the pixel bar 244 is not disconnected even when the pixel electrode 190 is partially lost in the pad area.

(184) Here, the pixel bar 234 is formed to be separated by a distance of 20 um from the first contact hole 155 so as not to overlap the first contact hole 155.

(185) The second contact hole 185 formed in the contact area is formed to have a size less than that of the lower metal 270. As an example, the second contact hole 185 is formed to have a size less by 10 um than that of one side of the lower metal 270.

(186) To prevent the contact of the pixel bar 234 from being broken at a boundary surface of the first contact hole 155, by expanding the length of the contact pattern 260 in the bridge layer 280 in the contact area, the contact pattern 260 is used as a bridge for a contact between the pixel bar 244 and the pixel pad 242.

(187) The contact pattern 260, as a bridge for contact of the pixel bar 244, may be expanded in length to a lower portion of the pixel bar 234. In this case, the contact pattern 260 may be formed using all transparent metals of the common electrode.

(188) In addition to the unit FPC pad/unit FPC shorting connection part 240, the unit on-off pad part 230 and the bump input dummy/bump output dummy part 250 may also connect the pad 242 and the pixel bar 244 by using the above-described bridge layer 280.

(189) The sizes of the second contact hole 185 and pad 242 in the second passivation layer 185 formed in the pad area may be changed, in which case the sizes are required to be sizes in which a test is capable of being performed with a probe tip.

(190) In the LCD device and the method of manufacturing the same according to the second embodiment of the present invention, the second passivation layer 180 and the pixel electrode 190 are simultaneously formed by the single mask process using the half tone mask, and thus, manufacturing efficiency increases.

(191) Moreover, in forming the pixel electrode 190, the present invention can prevent disconnection of the pixel bar 244, caused by loss of the pixel electrode 190 due to the lift-off process, in the pad area. Accordingly, the present invention can enhance the contact performance of the pixel bar 244 in the pad area.

(192) FIG. 25 is a view illustrating a plurality of masks that are used in a schematic manufacturing method and process of an LCD device with integrated touch sensor.

(193) Referring to FIG. 25, in the related art, a total of eleven masks are required in manufacturing a TFT array substrate with built-in touch sensor, but the number of masks can decrease by one or two in the manufacturing methods according to the first and second embodiments of the present invention.

(194) Specifically, as illustrated in FIG. 25A, by forming the second passivation layer (PAS2) and a pixel electrode (PXL) with one half tone mask, the number of used masks can decrease by one compared to the related art. Accordingly, a TFT array substrate with built-in touch sensor can be manufactured with a total of ten masks.

(195) Moreover, as illustrated in FIG. 25B, by forming the second passivation layer (PAS2) and a pixel electrode (PXL) with one half tone mask and forming a common electrode and a touch sensing line with one mask, the number of used masks can decrease by two compared to the related art. Accordingly, a TFT array substrate with built-in touch sensor can be manufactured with a total of nine masks.

(196) Accordingly, in manufacturing a TFT array substrate with built-in touch sensor, the number of masks can decrease, the manufacturing cost can be saved, and a time taken in manufacturing can be shortened.

(197) As described above, the method of manufacturing the LCD device simultaneously forms the passivation layer and the pixel electrode in the single mask process using the half tone mask, and thus can increase manufacturing efficiency.

(198) The method of manufacturing the LCD device can prevent disconnection, caused by loss of a pixel electrode due to the lift-off process, in the pad area.

(199) In the LCD device and the method of manufacturing the same, the contact performance of the pixel bar can be enhanced in the pad area.

(200) In addition to the aforesaid features and effects of the present invention, other features and effects of the present invention can be newly construed from the embodiments of the present invention.

(201) It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.