KR20130015126A - Liquid crystal display device with a built-in touch screen and method for manufacturing the same - Google Patents

Abstract

PURPOSE: An LCD(Liquid Crystal Display) device including a touch screen and a manufacturing method thereof are provided to reduce the number of masks by simultaneously forming a data contact line and a sensing line. CONSTITUTION: A light blocking layer(112) is formed on a glass substrate(110). After a buffer layer(114) is formed, an active layer(116) is formed on the buffer layer. After a gate insulating layer(122) and a gate(124) are formed, a source(118) and a drain(120) are formed. After an inter-layer insulating layer(126) and a first passivation layer(132) are formed, a common electrode(134) is formed on the first passivation layer. After a first contact hole is formed, a data contact layer(130) is formed on the first contact hole. A touch sensing line(136) is formed on the common electrode.

Description

Liquid crystal display with built-in touch screen and manufacturing method therefor {LIQUID CRYSTAL DISPLAY DEVICE WITH A BUILT-IN TOUCH SCREEN AND METHOD FOR MANUFACTURING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel display device, and more particularly, to a liquid crystal display device having a thin touch screen, and a liquid crystal display device having a touch screen that can reduce manufacturing costs and improve manufacturing efficiency by simplifying a manufacturing process. It relates to a manufacturing method.

With the development of various portable electronic devices such as mobile communication terminals and notebook computers, there is an increasing demand for a flat panel display device that can be applied thereto.

Among flat panel display devices, the liquid crystal display device has been expanding its application field due to development of mass production technology, ease of driving means, low power consumption, high image quality, and large screen.

Recently, a touch screen that allows a user to directly input information on the screen using a finger or a pen has been applied to replace the conventional input device such as a mouse or a keyboard as an input device of a liquid crystal display. Such a touch screen is being applied due to its ease of operation by anyone.

The touch screen is classified into an in-cell method that is refractory in a cell of a liquid crystal panel according to a structure that is combined with a liquid crystal panel, an on-cell method formed on an upper part of the liquid crystal panel, and an add-on method in which the touch screen is coupled to the outside of the liquid crystal panel. Can be.

In the application of a touch screen to a liquid crystal display, development has been made in a form in which a touch screen is embedded in a TFT array substrate (lower substrate) of a liquid crystal panel for slimming.

In this case, an in-cell touch type liquid crystal display device using a common electrode formed on the TFT array substrate as a touch sensing electrode and separately forming a sensing line connecting the common electrode formed on the pixels is developed. have.

FIG. 1 is a diagram schematically illustrating a liquid crystal display including a touch screen and a driving method thereof according to the related art.

In FIG. 1, a TFT array substrate structure in a FFS (Fringe Field Switch) mode is illustrated, and illustrations of the color filter array substrate (upper substrate) and the liquid crystal layer are omitted. 1 illustrates that the touch screen is internalized in the TFT array substrate as an in-cell touch type.

A plurality of pixels are formed on the TFT array substrate, each of which is defined by data lines (not shown) and gate lines (not shown) that cross each other.

Thin film transistors (TFTs) are formed in regions where the data lines intersect the gate lines. In addition, each of the plurality of pixels includes a common electrode Vcom electrode and a pixel electrode. In FIG. 1, only one pixel of a plurality of pixels formed on the TFT array substrate is shown.

Referring to FIG. 1, the TFT array substrate may include a glass substrate 10, a light shielding layer 12, a buffer layer 14, a TFT, a gate insulator 22, and an interlayer insulating layer. (26, ILD: Inter Layer Dielectric), a plurality of protective layers 28, 32, and 38: PAS0, PAS1, and PAS2, data contact 30, common electrode 34, and touch sensing line 36, a sensing line (3 ^rd metal) and a pixel electrode 42.

In the liquid crystal display device having a touch screen according to the related art including the above-described configuration, an image according to an image signal is adjusted by adjusting the transmittance of light passing through the liquid crystal layer of each pixel according to a data voltage and a common voltage applied to a pixel during a display period. Is displayed.

In the non-display period, the common electrodes 34 of the pixels connected by the touch sensing line 36 are driven by a touch sensing electrode to sense a change in capacitance Ctc according to a user's touch. do.

That is, the common electrode 34 functions as an electrode for supplying the common voltage Vcom to the pixel in the display period, and as a touch sensing electrode for detecting the touch in the non-display period.

2 is a diagram illustrating a method of manufacturing a liquid crystal display device having a touch screen according to the related art.

Referring to FIG. 2, in order to compensate for the disadvantages of the slow operation speed of the amorphous silicon (a-Si) TFT, the limitation of the fine line width design, and the like, the low-temperature polycrystalline silicon ( LTPS: Low Temperature Poly Silicon.

 When low temperature polycrystalline silicon (LTPS) is used to manufacture a liquid crystal display device with a touch screen according to the related art, as shown in FIG. 2, ten photolithography processes using ten masks are performed.

As such, when ten photolithography processes using ten masks are performed to manufacture a TFT array substrate, the tact time of the manufacturing process is long, resulting in a decrease in manufacturing efficiency and an increase in manufacturing cost.

In particular, a separate mask and photolithography process for forming the touch sensing line 36 on the TFT array substrate has a disadvantage in that manufacturing efficiency is lowered and manufacturing cost is increased.

These shortcomings are a major cause of the product competitiveness of the liquid crystal display device with a touch screen.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problem, and in the manufacture of a TFT array substrate (lower substrate), it is possible to provide a liquid crystal display device having a touch screen and a manufacturing method thereof in which a manufacturing process can be reduced by reducing a mask process. It is a technical problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and provides a liquid crystal display device having a touch screen and a method for manufacturing the same, which can improve manufacturing efficiency by simplifying a manufacturing process of a TFT array substrate (lower substrate). Shall be.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and a technical object of the present invention is to provide a liquid crystal display device having a touch screen and a method for manufacturing the same, which can reduce the thickness of a TFT array substrate (lower substrate).

Disclosure of Invention The present invention has been made in view of the above-described problems, and it is an object of the present invention to provide a liquid crystal display device having a touch screen and a method for manufacturing the same, which can improve driving performance.

Other features and advantages of the invention will be set forth in the description which follows, or may be obvious to those skilled in the art from the description and the claims.

Method of manufacturing a liquid crystal display device with a touch screen according to an embodiment of the present invention comprises the steps of forming a light shielding layer on a glass substrate; Forming a buffer layer formed to cover the light blocking layer, and forming an active on the buffer layer; Forming a thin film transistor (TFT) by forming a gate insulating layer and a gate so as to cover the active, and forming a source and a drain by doping impurities outside the active; Forming an interlayer insulating layer and a first protective layer to cover the gate; Forming a common electrode on the first passivation layer and forming a first contact hole exposing an upper surface of the drain; Forming a data contact in the first contact hole and forming a touch sensing line on the common electrode; Forming a second passivation layer exposing a top surface of the data contact; And forming a pixel electrode on the second passivation layer and on the data contact.

According to an embodiment of the present invention, a liquid crystal display including a touch screen may include: a light blocking layer formed on a glass substrate; A thin film transistor (TFT) formed on the light blocking layer; An interlayer insulating layer and a first protective layer formed to cover the TFT; A common electrode formed on the first protective layer; A touch sensing line formed on the common electrode; A data contact connected to the drain of the TFT through the gate insulating layer, the interlayer insulating layer, and the first protective layer of the TFT; A second passivation layer formed to cover the common electrode and the first passivation layer and exposing an upper surface of the data contact; And a pixel electrode formed on the second protective layer and connected to the data contact.

The manufacturing method of a liquid crystal display device with a touch screen according to an embodiment of the present invention can reduce manufacturing costs by reducing a mask process when manufacturing a TFT array substrate (lower substrate).

The manufacturing method of a liquid crystal display device with a touch screen according to an embodiment of the present invention can simplify the manufacturing process of the TFT array substrate (lower substrate), thereby improving manufacturing efficiency.

According to an exemplary embodiment of the present invention, a method of manufacturing a liquid crystal display device with a built-in touch screen may reduce the thickness of a TFT array substrate (lower substrate) to reduce the thickness of the liquid crystal display device.

According to an exemplary embodiment of the present invention, driving performance of a liquid crystal display having a touch screen may be improved.

Other features and effects of the present invention may be newly understood through the embodiments of the present invention in addition to the features and effects of the present invention mentioned above.

1 is a cross-sectional view schematically illustrating a structure of a liquid crystal display device having a touch screen according to the related art.
2 is a view illustrating a method of manufacturing a liquid crystal display device having a touch screen according to the related art.
3 is a cross-sectional view illustrating a structure of a liquid crystal display device having a touch screen according to an embodiment of the present invention.
4 to 13 illustrate a method of manufacturing a liquid crystal display device having a touch screen according to a first embodiment of the present invention.
14 to 20 are views illustrating a method of manufacturing a liquid crystal display device having a touch screen according to a second embodiment of the present invention.

Hereinafter, a liquid crystal display and a method of manufacturing the same in which a touch screen is built according to embodiments of the present invention will be described with reference to the accompanying drawings.

In describing embodiments of the present invention, when a structure (electrode, line, layer, contact) is described as being formed 'on or on' and 'under or under' another structure, these descriptions indicate that the structures It is to be interpreted as including the case of contact, as well as the case where a third structure is interposed between these structures.

The expressions 'above or on' and 'below or below' are used to describe the liquid crystal display and the manufacturing method thereof of the present invention based on the drawings. Thus, the expressions 'above or above' and 'below or below' may differ from each other in the manufacturing process and in the configuration after manufacture is complete.

Prior to the detailed description of the present invention with reference to the drawings, the liquid crystal display device includes a twisted nematic (TN) mode, a vertical alignment (VA) mode, an in plane switching (IPS) mode, and a fringing ring (FFS) according to a method of adjusting the arrangement of the liquid crystal layer. Field Switching) has been developed.

In the IPS mode and the FFS mode, a pixel electrode and a common electrode are disposed on a lower substrate, and the alignment of the liquid crystal layer is adjusted by an electric field between the pixel electrode and the common electrode.

In the IPS mode, the pixel electrode and the common electrode are alternately arranged in parallel to generate a transverse electric field between both electrodes to adjust the arrangement of the liquid crystal layer. Such an IPS mode has a disadvantage in that the arrangement of the liquid crystal layer is not controlled in the upper portion of the pixel electrode and the common electrode, thereby decreasing light transmittance in the region.

The FFS mode is designed to overcome the shortcomings of the IPS mode. In the FFS mode, the pixel electrode and the common electrode are formed to be spaced apart from each other with an insulating layer interposed therebetween.

In this case, one electrode is configured in a plate shape or a pattern and the other electrode is configured in a finger shape to adjust the arrangement of the liquid crystal layer through a fringe field generated between the two electrodes. That's the way.

A liquid crystal display with a touch screen according to embodiments of the present invention has the structure of the FFS mode. In addition, low temperature polysilicon (LTPS) may be used as a material of the TFT array substrate (lower substrate).

Prior to the description with reference to the drawings, a liquid crystal display device with a built-in touch screen according to an embodiment of the present invention includes an in-cell touch type liquid crystal panel with a built-in touch screen for detecting a touch position of a user; And a backlight unit and a driving circuit unit for supplying light to the liquid crystal panel.

The driving circuit unit includes a power supply unit for supplying driving power to a timing controller T-con, a data driver D-IC, a gate driver G-IC, a sensing driver, a backlight driving unit, and driving circuits.

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

3 is a cross-sectional view illustrating a structure of a liquid crystal display device having a touch screen according to an embodiment of the present invention.

3 illustrates that the touch screen is internalized in the TFT array substrate as an in-cell touch type, and only one pixel is shown among a plurality of pixels formed on the TFT array substrate.

In FIG. 3, the color filter array substrate (upper substrate), the liquid crystal layer, and the driving circuit unit are omitted from among the configurations of the liquid crystal display including the touch screen according to the embodiment of the present invention.

A plurality of pixels are formed on the TFT array substrate, each of which is defined by data lines (not shown) and gate lines (not shown) that cross each other.

A thin film transistor (TFT) is formed in each region where the data lines intersect the gate lines. In addition, each of the plurality of pixels includes a common electrode Vcom electrode and a pixel electrode.

Referring to FIG. 3, a TFT region in which a pixel region for displaying an image and a TFT for driving a pixel is formed is formed in a TFT array substrate.

In the TFT region, a TFT for supplying the pixel voltage applied from the data line to the pixel is formed.

The pixel electrode 142 and the common electrode 136 are formed in the pixel area, and the common electrodes 134 of the adjacent pixels are rowed or columned to drive the common electrode 134 as a touch electrode. A touch sensing line 136 is formed to connect in the direction.

Hereinafter, the configuration of the TFT array substrate will be described in detail with reference to the TFT region and the contact region where the pixel electrode and the TFT are connected.

The TFT array substrate may include a glass substrate 110, a light blocking layer 112, a buffer layer 114, a gate insulator 122, a common electrode 134, a Vcom electrode, a touch sensing line 136, Interlayer dielectric 126 (interlayer dielectric), data contact 130, pixel electrode 142, first protective layer 132, PAS1, and second protective layer 138, PAS2 And a TFT consisting of an active 116, a source 118, a drain 120, and a gate 124.

Specifically, the light blocking layer 112 is formed in the TFT region on the glass substrate 110, and the buffer layer 114 is formed thereon.

Here, the light blocking layer 112 may be formed of molybdenum (Mo) or aluminum (Al), and may have a thickness of 500 μs.

The buffer layer 114 may be formed of an inorganic material, for example, SiO ₂ , or SiN x, and may have a thickness of 2,000 μs to 3,000 μs.

An active 116, a source 118, and a drain 120 of the TFT are formed in an area overlapping the light blocking layer 112 on the buffer layer 114.

Here, the active 116 may be formed of low temperature polysilicon (P-Si), and may have a thickness of 500 μs. The source 118 and the drain 120 are formed by doping P-type or N-type impurities into the semiconductor layer of the active 116.

The gate insulating layer 122 is formed on the upper front surface of the buffer layer 114 to cover the active 116, the source 118, and the drain 120.

Here, the gate insulating layer 122 may be formed of SiO ₂ , and may have a thickness of 1,300 μs.

The gate insulating layer 122 may be formed by depositing TEOS (Tetra Ethyl Ortho Silicate) or MTO (Middle Temperature Oxide) by Chemical Vapor Deposition (CVD).

A gate 124 of the TFT is formed in a region overlapping the active 116 in the upper portion of the gate insulating layer 122.

Here, the gate 124 may be formed of aluminum (Al) or molybdenum (Mo), and may have a thickness of 3,000 kPa.

In this manner, the active 116, the source 118, the drain 120, and the gate 124 are formed with the gate insulating layer 122 interposed therebetween to form a TFT.

An interlayer insulating layer 126 is formed on the gate insulating layer 122 to cover the gate 124 of the TFT.

Here, the interlayer insulating layer 126 may be formed of SiO ₂ or SiNx, and may have a thickness of 6,000 μs. As another example, the interlayer insulating layer 126 may also be formed in a structure of SiO ₂ (3,000 mW) / SiNx (3,000 mW).

The first passivation layer 132 (PAS1) is formed on the interlayer insulating layer 126.

Here, the first protective layer 132 is formed of photo acryl to have a thickness of 3um to planarize the entire surface of the glass substrate 110.

Portions of the gate insulating layer 122, the interlayer insulating layer 126, and the first passivation layer 132 are etched to form a first contact hole for exposing the drain 120 of the TFT. The first contact hole is formed in the first contact hole. The data contact 130 is formed of a conductive metal material.

The data contact 130 electrically connects the drain 120 of the TFT and the pixel electrode 142.

For example, the data contact 130 may include molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be formed to have a thickness of 6,000 로 with a conductive metal material such as). As another example, the data contact 130 may be formed of a structure in which molybdenum (Mo) / aluminum (Al) / molybdenum (Mo) is stacked.

The common electrode 134 (Vcom electrode) is formed on the first passivation layer 132.

The common electrode 134 is a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), and may be formed to have a thickness of 500 μs.

The touch sensing line 136 is formed on one side of the common electrode 134.

Here, the conductive metal material is deposited on the first protective layer and the common electrode, and then patterned to form a data contact 130 in the first contact hole, and together with the touch sensing line on the common electrode 134. 136 is formed.

The touch sensing line 136 is formed on the common electrode 134 to cross the pixels to connect the common electrodes 134 of adjacent pixels. This allows the common electrode 134 to function as a touch sensing electrode.

The touch sensing line 136 may be formed of molybdenum (Mo) or aluminum (Al), and may have a thickness of 1,500 kPa to 2,000 kPa. The touch sensing line 136 may also be formed in a structure in which molybdenum (Mo) / aluminum (Al) / molybdenum (Mo) is stacked.

The touch sensing line 136 connects the common electrode 134 of adjacent pixels to form a touch block. In this case, the touch block includes a touch row block for detecting the touch position in the X-axis direction and a touch column block for detecting the touch position in the Y-axis direction.

Since the touch screen needs to recognize the coordinates of the X and Y axes in order to detect the touch position of the user, the touch row block and the touch column block should be separated from each other without contact.

To this end, the touch sensing line 136 of the touch column block is connected in the Y-axis direction by using a conductive line formed to overlap the data line of the TFT array substrate, so that the user's touch position is recognized in the Y-axis direction.

The touch sensing line 136 of the touch row block uses the gate metal formed together when the gate line is formed on the TFT array substrate as a bridge to avoid contact with the touch column block and to recognize the touch position of the user in the X-axis direction. do.

In this way, the touch row block and the touch column block are separated so that the touch position of the user is detected in the X and Y axis directions.

A second passivation layer 138 (PAS2) is formed on the first passivation layer 132 to cover the common electrode 134 and the touch sensing line 136.

Here, the second protective layer 138 may be formed of SiO ₂ , or SiNx, and may have a thickness of 2,000 μs to 3,000 μs.

A second contact hole is formed in an area of the second passivation layer 138 that overlaps the data contact 130 to expose the top surface of the data contact 130.

The pixel electrode 142 is formed in a pixel shape in the pixel area of the second passivation layer 138. In addition, a pixel electrode 142 is formed in the second contact hole and connected to the data contact 130. Through this contact structure, the drain 120 of the TFT and the pixel electrode 142 are connected via the data contact 130.

Here, the pixel electrode 142 is made of a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), and may be formed to have a thickness of 500 μs.

In the liquid crystal display according to the exemplary embodiment of the present invention including the above-described configuration, the arrangement of the liquid crystal layer is controlled through a fringe field generated between the common electrode 134 and the pixel electrode 142 during the display period. An image is displayed.

In the non-display period, the common electrodes 134 of the pixels connected through the touch sensing line 136 are driven as the touch sensing electrodes.

According to the user's touch, a touch capacitance Ctc is formed between the color filter array substrate (upper substrate) and the common electrode 134 of the TFT array substrate (lower substrate). The touch position of the user is detected by sensing the change in capacitance Ctc according to the touch.

According to an exemplary embodiment of the present invention, a liquid crystal display including a touch screen may form a TFT by applying low temperature polysilicon (LTPS), thereby improving driving performance of a liquid crystal display having a touch screen. have.

In addition, the liquid crystal display device with a touch screen according to an embodiment of the present invention can reduce the thickness of the TFT array substrate (lower substrate) by removing the protective layer PAS0 applied in the prior art.

4 to 13 illustrate a method of manufacturing a liquid crystal display device having a touch screen according to a first embodiment of the present invention. Hereinafter, a method of manufacturing a liquid crystal display device having a touch screen according to a first embodiment of the present invention will be described with reference to FIGS. 4 to 13.

4 to 13 illustrate a manufacturing method of internalizing a touch screen on a TFT array substrate with an in-cell touch type, and only one pixel is shown among a plurality of pixels formed on the TFT array substrate.

4 to 13, illustration of the manufacturing process for forming the color filter array substrate (upper substrate) and the liquid crystal layer is omitted.

First, referring to FIG. 4, a method of manufacturing a liquid crystal display device having a touch screen according to a first embodiment of the present invention may include a TFT array substrate having a touch screen using a photolithography process using eight masks. It can manufacture.

Through this, it is possible to reduce the mask required for the manufacturing process compared to the prior art (10 masks), thereby reducing the detailed process. In addition, by removing the process of forming the protective layer (PAS0) has been applied in the prior art it can also reduce the detailed process accordingly.

Specifically, referring to FIG. 5, a light shield metal layer is formed on a glass substrate 110 using a metal material that blocks light such as molybdenum (Mo).

Subsequently, the light shield metal layer is patterned through photolithography and wet etching using a mask to form a light shielding layer 112 in the TFT region. In this case, the light blocking layer 112 is formed to be aligned with the active 116 of the TFT formed in a subsequent process.

In FIG. 5, the glass substrate 110 is applied to the base of the TFT array substrate as an example. However, the plastic substrate may replace the glass substrate 110.

Although not shown in FIG. 5, the glass substrate 110 is formed such that a plurality of gate lines and a plurality of data lines cross each other. TFTs are formed in regions where the plurality of gate lines and the plurality of data lines intersect.

6, the buffer layer 114 is formed of an inorganic material, for example, SiO ₂ or SiN x on the glass substrate 110. In this case, the buffer layer 114 may have a thickness of 2,000 Å to 3,000 Å.

Thereafter, low temperature polysilicon (P-Si) or amorphous silicon (a-Si) is deposited on a region overlapping the light blocking layer 112 in the buffer layer 114 to form a semiconductor layer.

The semiconductor layer is then patterned through photolithography and dry etching processes using a mask to form the active 116 of the TFT. In this case, the active 116 may have a thickness of 500 kHz and may be aligned with the light blocking layer 112.

Subsequently, referring to FIG. 7, the gate insulating layer 122 is formed of SiO ₂ on the entire upper surface of the buffer layer 114 to cover the active 116. In this case, the gate insulating layer 122 may have a thickness of 1,300 Å.

The gate insulating layer 122 may be formed by depositing TEOS (Tetra Ethyl Ortho Silicate) or MTO (Middle Temperature Oxide) by Chemical Vapor Deposition (CVD).

Thereafter, the gate 124 of the TFT is formed of aluminum (Al) or molybdenum (Mo) in a region overlapping the active 116 in the upper portion of the gate insulating layer 122. In this case, the gate 124 may have a thickness of 3,000 Å.

Thereafter, the source 118 and the drain 120 of the TFT are formed by doping a P-type or N-type impurity on the outside of the active 116 using the gate 124 as a mask.

In this case, when the gate 124 is formed, a wet etching process and a dry etching process are performed. The active 116 may be N + or P + doped between the wet etching process and the dry etching process so that the source 118 and the drain ( 120).

In this manner, the active 116, the source 118, the drain 120, and the gate 124 are formed with the gate insulating layer 122 interposed therebetween to form a TFT.

Subsequently, referring to FIG. 8, an insulating material is deposited on the gate insulating layer 122 to cover the gate 124 to form an interlayer insulating layer 126 (ILD).

In this case, the interlayer insulating layer 126 may be formed of SiO ₂ or SiNx, and may have a thickness of 6,000 μs. As another example, the interlayer insulating layer 126 may also be formed in a structure of SiO ₂ (3,000 mW) / SiNx (3,000 mW).

Thereafter, a first passivation layer 132 (PAS1) is formed on the interlayer insulating layer 126. In this case, the first protective layer 132 is formed of photo acryl and is formed to have a thickness of 3 μm to planarize the entire surface of the glass substrate 110.

9, a portion of the gate insulating layer 122, the interlayer insulating layer 126, and the first passivation layer 132 is etched to expose the drain 120 of the TFT. 128).

In this case, the first contact hole 128 may be formed by sequentially forming the interlayer insulating layer 126 and the first protective layer 132, and then performing a dry etching process continuously.

Subsequently, referring to FIG. 10, a common electrode 134 (Vcom electrode) is formed on the first passivation layer 132.

The common electrode 134 is a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), and may be formed to have a thickness of 500 μs.

In the prior art, the interlayer insulating layer ILD was etched to form a contact hole exposing the top surface of the drain of the TFT, and then a data contact was formed. Thereafter, after forming the first passivation layer PAS1, two masks were required to sequentially form the common electrode and the touch sensing line thereon.

On the other hand, in the manufacturing method of the liquid crystal display device with a touch screen according to the first embodiment of the present invention, the interlayer insulating layer 126 and the first protective layer 132 through the manufacturing process of FIGS. 8 and 9 described above. After sequentially forming, the dry etching process was continuously performed to form the first contact hole 128 exposing the top surface of the drain 120. Through this, the number of masks can be reduced and manufacturing process time and manufacturing cost can be reduced.

Subsequently, referring to FIG. 11, after the conductive metal material is coated in the first contact hole 128, a photolithography and etching process using a mask is performed to form the data contact 130 to be connected to the drain 120. do.

This data contact 130 electrically connects the drain 120 of the TFT and the pixel electrode 142 formed in the manufacturing process described later.

For example, the data contact 130 may include molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be formed to have a thickness of 6,000 로 with a conductive metal material such as). As another example, the data contact 130 may be formed of a structure in which molybdenum (Mo) / aluminum (Al) / molybdenum (Mo) is stacked.

The touch sensing line 136 is formed on the common electrode 134 using the process of forming the data contact 130.

After the conductive metal material is deposited on the first protective layer and the common electrode, the conductive metal material is patterned to form a data contact 130 in the first contact hole 128, and with the touch sensing line on the common electrode 134. 136 is formed.

That is, when patterning the conductive metal material applied to form the data contact 130, the touch sensing line 136 is formed by allowing the conductive metal material to remain on the common electrode 134.

The touch sensing line 136 is formed on the common electrode 134 to cross the pixels to connect the common electrodes 134 of adjacent pixels. This allows the common electrode 134 to function as a touch sensing electrode.

Here, the touch sensing line 136 may be formed of molybdenum (Mo) or aluminum (Al), and may have a thickness of 1,500 kPa to 2,000 kPa. The touch sensing line 136 may also be formed in a structure in which molybdenum (Mo) / aluminum (Al) / molybdenum (Mo) is stacked.

In the prior art, a process of forming a data contact and a process of forming a touch sensing line were performed using separate masks, and thus two masks were required.

On the other hand, in the manufacturing method of the liquid crystal display device with a touch screen according to the first embodiment of the present invention, the data contact 130 and the touch sensing line 136 using one mask through the manufacturing process of FIG. 11. By simultaneously forming, the number of masks can be reduced, and manufacturing process time and manufacturing cost can be reduced.

Next, referring to FIG. 12, a second passivation layer 138 (PAS2) is formed on the first passivation layer 132 to cover the common electrode 134 and the touch sensing line 136.

Here, the second protective layer 138 may be formed of SiO ₂ , or SiNx, and may have a thickness of 2,000 μs to 3,000 μs.

Thereafter, a second contact hole 140 is formed in an area of the second protective layer 138 that overlaps with the data contact 130 to expose the top surface of the data contact 130.

Subsequently, referring to FIG. 13, a pixel electrode 142 is formed in a pixel shape in a pixel area among the second passivation layer 138. In addition, a pixel electrode 142 is also formed in the second contact hole 140 to be connected to the data contact 130.

Through such a contact structure, the drain 120 of the TFT and the pixel electrode 142 are connected via the data contact 130.

Here, the pixel electrode 142 is made of a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), and may be formed to have a thickness of 500 μs.

Through the manufacturing process of FIG. 4 to FIG. 13 described above, a liquid crystal display device having a touch screen according to an embodiment of the present invention may be manufactured.

14 to 20 are views illustrating a method of manufacturing a liquid crystal display device having a touch screen according to a second embodiment of the present invention.

Hereinafter, a method of manufacturing a liquid crystal display device having a touch screen according to a second embodiment of the present invention will be described with reference to FIGS. 14 to 20.

First, referring to FIG. 14, a method of manufacturing a liquid crystal display device having a touch screen according to a second embodiment of the present invention may include a TFT array substrate having a touch screen using a photolithography process using eight masks. It can manufacture.

Through this, it is possible to reduce the mask required for the manufacturing process compared to the prior art (10 masks), thereby reducing the detailed process. In addition, by removing the process of forming the protective layer (PAS0) has been applied in the prior art it can also reduce the detailed process accordingly.

The manufacturing method of the liquid crystal display device with a touch screen according to the second embodiment of the present invention is the same as the above-described first embodiment until the process of forming the first protective layer 132. Therefore, detailed descriptions up to the process of forming the first protective layer 132 will be omitted, and FIGS. 5 to 8 and detailed description thereof will be referred to.

Referring to FIG. 5, after forming the light blocking layer 112, the TFT, the interlayer insulating layer 126, and the first protective layer 132 on the glass substrate 110, the TFT of the first protective layer 132 may be formed. The first contact hole 128 is formed by dry etching the region overlapping the drain 120. At this time, since the gate insulating layer 122 and the interlayer insulating layer 126 are not etched, the drain 120 of the TFT is not exposed.

Next, referring to FIG. 16, a common electrode 134 (Vcom electrode) is formed on the first passivation layer 132.

The common electrode 134 is a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), and may be formed to have a thickness of 500 μs.

Next, referring to FIG. 17, during the process of forming the common electrode 134, the gate insulating layer 122 and the interlayer insulating layer 126 in the first contact hole 128 region are dry-etched to remove the drain 120. Expose the top surface.

In the prior art, the interlayer insulating layer ILD was etched to form a contact hole exposing the top surface of the drain of the TFT, and then a data contact was formed. Thereafter, after forming the first passivation layer PAS1, two masks were required to sequentially form the common electrode and the touch sensing line thereon.

On the other hand, in the manufacturing method of the liquid crystal display device with a touch screen according to the second embodiment of the present invention, the process of forming the common electrode 134 and the drain 120 through the manufacturing process of FIGS. 16 and 17 described above. It is possible to reduce the number of masks and to reduce the manufacturing process time and manufacturing cost by performing a process of exposing the mask with one sheet.

18, after the conductive metal material is coated in the first contact hole 128, a photolithography and etching process using a mask is performed to form the data contact 130 to be connected to the drain 120. do.

This data contact 130 electrically connects the drain 120 of the TFT and the pixel electrode 142 formed in the manufacturing process described later.

For example, the data contact 130 may include molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be formed to have a thickness of 6,000 로 with a conductive metal material such as). As another example, the data contact 130 may be formed of a structure in which molybdenum (Mo) / aluminum (Al) / molybdenum (Mo) is stacked.

The touch sensing line 136 is formed on the common electrode 134 using the process of forming the data contact 130.

After the conductive metal material is deposited on the first protective layer and the common electrode, the conductive metal material is patterned to form a data contact 130 in the first contact hole 128, and with the touch sensing line on the common electrode 134. 136 is formed.

That is, when patterning the conductive metal material applied to form the data contact 130, the touch sensing line 136 is formed by allowing the conductive metal material to remain on the common electrode 134.

The touch sensing line 136 is formed on the common electrode 134 to cross the pixels to connect the common electrodes 134 of adjacent pixels. This allows the common electrode 134 to function as a touch sensing electrode.

Here, the touch sensing line 136 may be formed of molybdenum (Mo) or aluminum (Al), and may have a thickness of 1,500 kPa to 2,000 kPa. The touch sensing line 136 may also be formed in a structure in which molybdenum (Mo) / aluminum (Al) / molybdenum (Mo) is stacked.

In the prior art, a process of forming a data contact and a process of forming a touch sensing line were performed using separate masks, and thus two masks were required.

On the other hand, in the manufacturing method of the liquid crystal display device with a touch screen according to the first embodiment of the present invention, the data contact 130 and the touch sensing line 136 using one mask through the manufacturing process of FIG. 18. By simultaneously forming, the number of masks can be reduced, and manufacturing process time and manufacturing cost can be reduced.

Subsequently, referring to FIG. 19, second protective layers 138 and PAS2 are formed on the first protective layer 132 to cover the common electrode 134 and the touch sensing line 136.

Here, the second protective layer 138 may be formed of SiO ₂ , or SiNx, and may have a thickness of 2,000 kPa to 3,000 kPa.

Thereafter, a second contact hole 140 is formed in an area of the second protective layer 138 that overlaps with the data contact 130 to expose the top surface of the data contact 130.

Next, referring to FIG. 20, the pixel electrode 142 is formed in a pixel shape in a pixel area among the upper portions of the second passivation layer 138. In addition, a pixel electrode 142 is also formed in the second contact hole 140 to be connected to the data contact 130.

Through such a contact structure, the drain 120 of the TFT and the pixel electrode 142 are connected via the data contact 130.

Here, the pixel electrode 142 is made of a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), and may be formed to have a thickness of 500 μs.

According to the manufacturing process of FIGS. 14 to 20 described above, a liquid crystal display device having a touch screen according to an exemplary embodiment may be manufactured.

The manufacturing method of a liquid crystal display device with a touch screen according to embodiments of the present invention can reduce manufacturing costs by reducing a mask process when manufacturing a TFT array substrate (lower substrate).

In addition, the manufacturing process of the TFT array substrate (lower substrate) can be simplified to improve the manufacturing efficiency. In addition, it is possible to reduce the thickness of the TFT array substrate (lower substrate) to make the thickness of the liquid crystal display device slim.

The second protective layer 138 and the pixel electrode 142 may be simultaneously formed through a single mask process using a half tone mask (HTM).

In this case, the second protective layer 138 is etched to form the second contact hole 140 by exposing the upper surface of the data contact 130 by performing a photolithography process and an etching process using a halftone mask.

Thereafter, after applying and patterning the photoresist PR on the second passivation layer 138, a pixel electrode layer is formed thereon, ashing the photoresist PR, and then a lift off process is performed. In this manner, the pixel electrode 134 may be formed in a finger shape.

By simultaneously forming the second passivation layer 138 and the pixel electrode 142 using the halftone mask, the mask required for the manufacturing process may be further reduced, and thus manufacturing time and manufacturing cost may be further reduced.

It will be understood by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

110: glass substrate 112: light shielding layer
114: buffer layer 116: active
118: source 120: drain
122: gate insulating layer 124: gate
126: interlayer insulating layer 128: first contact hole
130: data contact 132: first protective layer
134: common electrode 136: touch sensing line
138: second protective layer 140: second contact hole
142: pixel electrode

Claims (10)

In the method of manufacturing a liquid crystal display device having a touch screen embedded in a TFT array substrate,
Forming a light shielding layer on the glass substrate;
Forming a buffer layer formed to cover the light blocking layer, and forming an active on the buffer layer;
Forming a thin film transistor (TFT) by forming a gate insulating layer and a gate so as to cover the active, and forming a source and a drain by doping impurities outside the active;
Forming an interlayer insulating layer and a first protective layer to cover the gate;
Forming a common electrode on the first passivation layer and forming a first contact hole exposing an upper surface of the drain;
Forming a data contact in the first contact hole and forming a touch sensing line on the common electrode;
Forming a second passivation layer exposing a top surface of the data contact; And
And forming a pixel electrode on the second passivation layer and on the data contact. 2. The method of claim 1,
In the step of forming a common electrode on the first protective layer, and forming a first contact hole for exposing the top surface of the drain,
Dry etching is continuously performed on a portion of the gate insulating layer, the interlayer insulating layer, and the first passivation layer to form a first contact hole exposing an upper surface of the drain, and forming a common electrode on the first passivation layer Method of manufacturing a liquid crystal display device with a touch screen, characterized in that. The method of claim 1,
In the step of forming a common electrode on the first protective layer, and forming a first contact hole for exposing the top surface of the drain,
After dry etching the first protective layer in the region overlapping with the drain, a common electrode is formed on the first protective layer,
And forming a first contact hole by dry etching the gate insulating layer and the interlayer insulating layer in a region overlapping with the drain. The method according to claim 2 or 3,
Forming a data contact in the first contact hole and forming a touch sensing line on the common electrode;
And the data contact and the touch sensing line are simultaneously formed through a single mask process. The method of claim 4, wherein
Depositing a conductive metal material on the first protective layer and the common electrode, and then patterning to form a data contact with the conductive metal material in the first contact hole, and forming a touch sensing line on the common electrode with the conductive metal material Method of manufacturing a liquid crystal display device with a touch screen, characterized in that. The method of claim 5, wherein
And a common electrode of adjacent pixels through the touch sensing line so that the common electrode functions as a touch electrode. The method of claim 1,
And forming a TFT, a data contact, a pixel electrode, a common electrode, and a touch sensing line on a TFT array substrate using eight masks. In a liquid crystal display device having a touch screen embedded in a TFT array substrate,
A light blocking layer formed on the glass substrate;
A thin film transistor (TFT) formed on the light blocking layer;
An interlayer insulating layer and a first protective layer formed to cover the TFT;
A common electrode formed on the first protective layer;
A touch sensing line formed on the common electrode;
A data contact connected to the drain of the TFT through the gate insulating layer, the interlayer insulating layer, and the first protective layer of the TFT;
A second passivation layer formed to cover the common electrode and the first passivation layer and exposing an upper surface of the data contact; And
And a pixel electrode formed on the second protective layer and connected to the data contact. The method of claim 8,
And the data contact and the touch sensing line are simultaneously formed of a contact hole exposing an upper surface of the drain and a conductive metal material formed on the common electrode. The method of claim 8,
And a common electrode of adjacent pixels connected to the touch sensing line to function as the touch electrode.

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