KR101949924B1 - In-Plane switching mode liquid crystal display device - Google Patents

Abstract

The present invention provides a liquid crystal display device comprising: a first substrate and a second substrate which are defined by a display region and a non-display region and which are adhered to each other with a liquid crystal layer interposed therebetween; Gate lines and data lines formed to define a plurality of pixel regions intersecting with each other in the display region of the inner surface of the first substrate; A common wiring formed on an inner surface of the first substrate so as to be parallel to the gate wiring; A thin film transistor connected to the gate wiring and the data wiring and formed in each of the pixel regions; A color filter layer formed on the thin film transistor and having red, green, and blue color filter patterns sequentially repeating over the display region; A first protective layer formed on the color filter layer; And a vertical portion formed to overlap with the data line on the first protective layer and a horizontal portion overlapping the gate line and the common line, An auxiliary common wiring; A plurality of bar-shaped central common electrodes branched from the horizontal portion of the auxiliary common wiring in each pixel region above the first protective layer; And a plurality of bar-shaped pixel electrodes connected to the thin film transistors on the first protective layer and alternating with the plurality of central common wirings in the pixel regions.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a liquid crystal display (LCD)

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a transverse electric field type liquid crystal display device capable of improving the aperture ratio and reducing the number of mask processes and a method of manufacturing the same.

Recently, liquid crystal display devices have been attracting attention as next generation advanced display devices with low power consumption, good portability, and high value-added.

In general, a liquid crystal display device is driven by using optical anisotropy and polarization properties of a liquid crystal. Since the liquid crystal has a long structure, it has a directionality in the arrangement of molecules, and the direction of the molecular arrangement can be controlled by artificially applying an electric field to the liquid crystal.

Therefore, when the molecular alignment direction of the liquid crystal is arbitrarily adjusted, the molecular arrangement of the liquid crystal is changed, and light is refracted in the molecular alignment direction of the liquid crystal by optical anisotropy, so that image information can be expressed.

At present, active matrix liquid crystal display devices (hereinafter, abbreviated as liquid crystal display devices) in which a thin film transistor and pixel electrodes connected to the thin film transistor are arranged in a matrix manner have been receiving the most attention because of their excellent resolution and video realization ability.

Such a liquid crystal display device generally comprises a color filter substrate on which a common electrode is formed, an array substrate on which pixel electrodes are formed, and a liquid crystal interposed between the two substrates. In such a liquid crystal display device, And the characteristics such as the transmittance and the aperture ratio are excellent.

However, liquid crystal driving by an electric field that is applied up and down has a drawback that the viewing angle characteristic is not excellent.

Therefore, in order to overcome the above disadvantages, a transverse electric field type liquid crystal display device having both a common electrode and a pixel electrode provided on an array substrate and being driven by a transverse electric field has been proposed.

Hereinafter, a general transverse electric field type liquid crystal display device will be described in detail with reference to FIG.

1 is a cross-sectional view of a general transverse electric field type liquid crystal display device.

As shown in the figure, in a general transverse electric field liquid crystal display device, an upper substrate 9 as a color filter substrate and a lower substrate 10 as an array substrate are opposed to each other with a gap therebetween, and between the upper and lower substrates 9 and 10 A liquid crystal layer 11 is interposed.

A common electrode 17 having a bar shape and a pixel electrode 30 are alternately formed on the same substrate on the lower substrate 10. The liquid crystal layer 11 is formed on the common electrode 17 17 and the horizontal electric field L by the pixel electrode 30.

2A and 2B are cross-sectional views respectively showing the on and off states of a general transverse electric field type liquid crystal display device.

2A showing the alignment state of the liquid crystal in the ON state to which the voltage is applied, the phase of the liquid crystal 11a at the position corresponding to the common electrode 17 and the pixel electrode 30 is The liquid crystal 11b located between the common electrode 17 and the pixel electrode 30 is formed by a horizontal electric field L formed by applying a voltage between the common electrode 17 and the pixel electrode 30, And arranged in the same direction as the horizontal electric field (L). That is, in the transverse electric field type liquid crystal display device, since the liquid crystals 11a and 11b operate by the horizontal electric field, the viewing angle becomes wide.

Therefore, when viewed from the front, the transverse electric-field-type liquid-crystal display device can be seen in the direction of about 80 to 89 degrees in the up / down / left / right directions without reversal.

2B, a horizontal electric field is not formed between the common electrode 17 and the pixel electrode 30 because the liquid crystal display device is in an off state in which no voltage is applied to the liquid crystal display device. Therefore, The array status does not change.

3 is a cross-sectional view of a portion of a conventional transverse electric field type liquid crystal display device in which a central portion of one pixel region is cut.

As shown in the drawing, a conventional general transverse electric-field liquid crystal display device 95 comprises an array substrate 40, a color filter substrate 70 and a liquid crystal layer 90 interposed between these two substrates 40 and 70 have.

(Not shown) that are arranged parallel to the gate wiring (not shown) in parallel with the gate wiring (not shown) spaced apart from each other by a predetermined distance in the array substrate 40 A data line 50 which intersects the wiring (not shown) and the gate and the common wiring (not shown), particularly crosses the gate wiring (not shown) and defines the pixel region P, And the lower part and the upper part.

In each pixel region P, a thin film transistor (not shown) formed of a gate electrode (not shown), a semiconductor layer (not shown), and a source and a drain electrode (not shown) is formed. And a protective layer 60 is formed.

A drain electrode (not shown) is formed in the pixel region P through a drain contact hole (not shown) exposing a drain electrode (not shown) of the thin film transistor (not shown) And a plurality of bar-shaped common electrodes 62 (not shown), which are alternately connected to the pixel electrodes 64 through common contact holes (not shown) Is formed.

In this case, the bar-shaped pixel electrode 64 and the common electrode 62 formed on the protective layer 48 are typically formed of a single layer structure of a transparent conductive material or an opaque metal material.

Corresponding to the array substrate 40 having such a configuration, the color filter substrate 70 is provided with red, green, and blue sub-pixels corresponding to the regions surrounded by the black matrix 73 and the black matrix 73, The color filter layer 76 is formed in such a manner that the blue color filter patterns 76a, 76b, and 76c are sequentially and repeatedly formed.

An overcoat layer 78 is formed to cover the color filter layer 76. A gap forming spacer (not shown) having a first height at the boundary of the pixel region P and a second gap (Not shown) having a height is formed.

However, in the conventional transverse electric field liquid crystal display device 95 having such a configuration, the black matrix 73 is formed in consideration of the adhesion margin of the array substrate 40 and the color filter substrate 70 to the color filter substrate 70 The aperture ratio is lowered. Furthermore, in each pixel region, a common contact hole is provided to bring the common wiring and the common electrode into contact with each other, thereby further decreasing the aperture ratio.

In the conventional transverse electric field type liquid crystal display device 95, the reflectance by the common electrode 62 and the pixel electrode 64 is 60% or more when exposed to external light, resulting in iridescence. ambient contrast ratio) is reduced.

Disclosure of the Invention The present invention has been devised to solve the problems of the conventional transverse electric field type liquid crystal display device, and it is an object of the present invention to improve the aperture ratio, reduce the reflectance due to external light to suppress the occurrence of rainbow stains, The present invention provides a transverse electric field type liquid crystal display device having an excellent display quality both indoors and outdoors by improving the display quality.

According to an aspect of the present invention, there is provided a transverse electric field type liquid crystal display device comprising: a first substrate and a second substrate which are defined by a display area and a non-display area and are aligned with each other with a liquid crystal layer interposed therebetween; Gate lines and data lines formed to define a plurality of pixel regions intersecting with each other in the display region of the inner surface of the first substrate; A common wiring formed on an inner surface of the first substrate so as to be parallel to the gate wiring; A thin film transistor connected to the gate wiring and the data wiring and formed in each of the pixel regions; A color filter layer formed on the thin film transistor and having red, green, and blue color filter patterns sequentially repeating over the display region; A first protective layer formed on the color filter layer; And a vertical portion formed to overlap with the data line on the first protective layer and a horizontal portion overlapping the gate line and the common line, An auxiliary common wiring; A plurality of bar-shaped central common electrodes branched from the horizontal portion of the auxiliary common wiring in each pixel region above the first protective layer; And a plurality of bar-shaped pixel electrodes connected to the thin film transistors on the first passivation layer and alternating with the plurality of central common electrodes in each of the pixel regions.

At this time, on the first substrate, an outermost common electrode branched from the common wiring and adjacent to the data wiring is formed in each of the pixel regions, and the vertical portion of the auxiliary common wiring is also connected to the outermost common electrode And is formed by overlapping.

In addition, a columnar gap-forming spacer having a first height corresponding to the boundary of the pixel region and spaced apart by a predetermined distance is formed on the inner surface of the second substrate, and a spacer having a second height lower than the first height, Shaped push-off spacer is formed.

Further, the auxiliary common wiring, the pixel electrode, and the central common electrode have a double layer structure of a lower layer made of an opaque metal material and an upper layer made of a transparent conductive material or copper nitride (CuNx). In this case, (ITO), indium-zinc-oxide (IZO), and aluminum-doped zinc-oxide (AZO).

The common wiring may be a first storage electrode, and the drain electrode of the thin film transistor may be formed to overlap with the first storage electrode to form a second storage electrode. The first storage electrode, the gate electrode, 2 The storage electrode features a storage capacitor.

In addition, a second passivation layer made of an inorganic insulating material is formed on the entire surface of the first substrate between the thin film transistor and the color filter layer, and the first passivation layer, the color filter layer, and the second passivation layer A drain contact hole exposing a drain electrode of the thin film transistor is provided and the pixel electrode is in contact with a drain electrode of the thin film transistor through the drain contact hole.

A pixel pattern for connecting one end of the bar-shaped pixel electrode is formed on the first passivation layer in each pixel region.

In addition, the data line, the pixel electrode, the outermost pixel electrode, and the central common electrode are symmetrically bent with respect to the center of each pixel region, so that each pixel region forms a double domain.

The vertical portion of the auxiliary common wiring may surround the spacing region between the data wiring and the outermost common electrode and the horizontal portion of the auxiliary common wiring may cover the spacing region between the common wiring and the gate wiring to prevent light leakage It is a feature that plays a role.

The transverse electric field type liquid crystal display device according to the present invention omits the black matrix formed in consideration of the adhesion margin with respect to the array substrate on the color filter substrate and omits the common contact holes provided in the respective pixel regions, .

A common electrode having a bar shape formed on a protective layer and a pixel electrode are made to have a double layer structure of an opaque metal material and a transparent conductive material having a low resistance property to reduce the reflectance due to external light to 39% It has an effect of suppressing occurrence of stain and improving the ambient contrast ratio.

Further, omitting the black matrix on the color filter substrate can reduce the material cost and the number of mask processes, thereby simplifying the process and reducing the manufacturing cost.

In addition, since the common electrode and the pixel electrode in the form of a bar are formed in a line-symmetrical structure in which the data lines and the pixel electrodes are vertically folded in each pixel region, a dual domain is implemented to suppress the chrominance due to the change of the viewing angle .

1 is a cross-sectional view schematically showing a part of a general transverse electric field type liquid crystal display device.
FIGS. 2A and 2B are cross-sectional views respectively showing the on and off states of a general transverse electric field liquid crystal display device;
3 is a cross-sectional view of one pixel region in a conventional general transverse electric field type liquid crystal display device.
4 is a plan view of one pixel region including a switching element in a transverse electric field type liquid crystal display according to an embodiment of the present invention.
5 is a cross-sectional view of a portion cut along line V-V in Fig. 4; Fig.
FIG. 6 is a cross-sectional view of a portion of FIG. 4 taken along line VI-VI; FIG.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 4 is a plan view of a pixel region including a switching element in a transverse electric field type liquid crystal display according to an embodiment of the present invention.

A transverse electric field type liquid crystal display 100 according to an embodiment of the present invention includes an array substrate 102 having a pixel electrode 170, a common electrode 173 and a color filter layer 150, And a liquid crystal layer 195 sandwiched between the two substrates 102 and 181. The liquid crystal layer 195 is formed of a liquid crystal layer 195,

The array substrate has a gate insulating film (not shown) interposed therebetween on a transparent insulating substrate (not shown) made of a glass or plastic material forming a base, and a plurality of pixel regions P A plurality of gate wirings 103 and a data wiring 130 are formed.

A common wiring 109 is formed on the insulating substrate (not shown) and made of the same material as the gate wiring 103, spaced apart from the gate wiring 103, passing through each pixel region P,

The gate lines 103 and the data lines 130 are connected to the gate lines 103 and the data lines 130 in the respective pixel regions P to form thin film transistors Tr Is formed.

The thin film transistor Tr is composed of sequentially stacked gate electrodes 105, a gate insulating film (not shown), a semiconductor layer (not shown) and source and drain electrodes 133 and 136 spaced from each other .

On the other hand, in the respective pixel regions P, the common wiring 109 is formed in the same layer in which the common wiring 109 is formed. The common wiring 109 is branched from the common wiring 109, The electrode 116 is formed.

A color filter layer (not shown) made up of red, green and blue color filter patterns (not shown) which are sequentially and repeatedly formed corresponding to each pixel region P as one of the most characteristic structures of the present invention is formed on the thin film transistor Tr And is formed on the entire display area for displaying an image.

At this time, the boundary of each color filter pattern (not shown) is located at the boundary of each pixel region P, and the black matrix normally formed at the boundary of each color filter pattern (not shown) .

In the upper portion of the color filter layer (not shown) having such a configuration, the outermost common electrode 116 provided on both sides of the data line 130, and the vertical An auxiliary common wiring 175 composed of a portion 175a and the gate wiring 103 and the horizontal portion 175b overlapping the common wiring 109 and the spacing regions of these two components 103 and 109 is formed . Therefore, the auxiliary common wiring 175 having such a configuration is substantially in the form of a lattice.

These auxiliary common wirings 175 are connected to the gate wirings 103 and the common wirings 109 corresponding to the gate wirings 103, the common wirings 109 and the data wirings 130 forming the boundaries of the pixel regions P, Of the conventional liquid crystal display device (95 in FIG. 3) by covering the spacing region between the data line 130 and the outermost common electrode 116. As a result, 3 in FIG. 3) provided in the black matrix (70 in FIG. 3).

In this case, since the auxiliary common wiring 175 is formed on the array substrate, it is unnecessary to consider the cohesion margin, so that it can be formed to have a smaller width than the width of the conventional black matrix (73 in FIG. 3) .

Each of the pixel regions P is provided with a plurality of central common electrodes (not shown) which are branched from the horizontal portion 175b of the auxiliary common wiring 175 and are parallel to the outermost common electrode 216 173 are formed at regular intervals.

At this time, the characteristic feature of the present invention is that the central portion common electrode 173 and the common contact hole for contacting the common wiring 109 are omitted in each pixel region P.

That is, the common line 109 and the auxiliary common line 175 on the characteristic of the transverse electric field type liquid crystal display device 100 according to the embodiment of the present invention are arranged in a non-display area (not shown) outside the display area including a plurality of pixel areas And the auxiliary common wiring 175 is electrically connected to the display region through a separate contact hole by a lower layer 175a made of moly titanium (MoTi), which is an opaque metal material having a low resistance characteristic, (95 in FIG. 3) in which each of the pixel regions P is in contact with each other through the common contact hole.

Therefore, the transverse electric field type liquid crystal display device 100 according to the embodiment of the present invention has a structure in which the common wiring 109 and the auxiliary common wiring 175 are electrically connected in the non-display area, and the common wiring 109 And the central common electrode 173 are omitted for the purpose of electrically connecting the pixel region P and the central common electrode 173. The effect of further increasing the aperture ratio of each pixel region P .

A pixel pattern 169 connected to the drain electrode 136 of the thin film transistor Tr through the drain contact hole 157 is formed in each pixel region P so as to overlap with the common wiring 109 And a plurality of pixel electrodes 170 branched in the pixel pattern 169 and having a bar shape alternate with the plurality of central common electrodes 173 to the inside of the outermost common electrode 116 .

The outermost common electrode 116 and the central common electrode 173 and the pixel electrode 170 having a bar shape are arranged in parallel with the gate wiring 103 located at the center of each pixel region P The upper and lower portions of the pixel region P are symmetrically bent at a predetermined angle with respect to a virtual reference line so that the upper and lower portions of the pixel region P are connected to the common electrodes 116 and 173 and the pixel electrode 170, Are formed in different directions to form a double-domain structure.

The implementation of the dual domain by forming the common electrodes 116 and 173 and the pixel electrode 170 in different directions in one pixel region P suppresses the chrominance due to the change in the viewing angle of the user, .

 The plurality of pixel electrodes 170 and the common electrodes 116 and 173 are bent in the pixel regions P so that the data lines 130 are also aligned with the center of each pixel region P And has a symmetrically deflected configuration.

Since the data lines 130 are not formed separately for each pixel region P but are connected to the entire display region, the data lines 130 are formed in a central portion of each pixel region P in the display region It is characterized in that it forms a zigzag shape which is bent by reference.

The common electrodes 116 and 173 and the pixel electrodes 170 and the data lines 130 are formed in the center portion of each pixel region P in the case of the array substrate for the transverse electric field type liquid crystal display device 100 according to the embodiment of the present invention, The common electrodes 116 and 173 and the pixel electrodes 170 and the data lines 130 must be formed in a central portion of each pixel region P as shown in FIG. It is not necessary to form a folded structure by reference, and it may be a straight line.

On the other hand, the common wiring 109 and the common wiring 109 overlap each other with a gate insulating film (not shown) interposed therebetween by overlapping the common wiring 109 and extending the drain electrode 136 in each pixel region P, Drain electrodes 136 constitute first and second storage electrodes 110 and 138. The first and second storage electrodes 110 and 138 and a gate insulating film (not shown) (StgC).

In the transverse electric field type liquid crystal display according to the embodiment of the present invention, the auxiliary common wiring 175, the pixel pattern 169, the central common electrode 173 in the form of a bar, Layer structure so that the electrode 170 has a reflectance of 39% or less due to external light.

In this case, the sub-layers (not shown) of the auxiliary common wiring 175 and the pixel pattern 169 having the bilayer structure and the pixel electrode 170 and the central common electrode 173 are opaque (ITO), indium-zinc-oxide (IZO), aluminum-doped zinc-oxide (AZO), and the like, which are transparent conductive materials, , Or copper nitride (CuNx) which is an opaque metal material.

On the other hand, a counter substrate (not shown) positioned corresponding to an array substrate (not shown) having such a structure is formed of a black resin material including black pigment, Spacers (not shown) having a height are formed spaced apart from each other by a predetermined distance, and at the same time, pillar-shaped spacers (not shown) having a second height smaller than the first height are spaced apart from each other by a predetermined distance .

A liquid crystal layer (not shown) is resumed between the array substrate (not shown) and the counter substrate (not shown) having such a configuration, and the end of the gap forming spacer (not shown) And the other end of each of the components.

At this time, the non-display area serves as an adhesive to surround the liquid crystal layer (not shown) so that the array substrate (not shown) and the counter substrate (not shown) A transverse electric field type liquid crystal display device 100 according to an embodiment of the present invention is completed by providing a seal pattern (not shown).

Hereinafter, a cross-sectional structure of a transverse electric field type liquid crystal display device having such a planar configuration according to an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 5 is a cross-sectional view taken along the section line V-V in FIG. 4, and FIG. 6 is a cross-sectional view taken along the section line VI-VI in FIG. For convenience of description, a region where the thin film transistor Tr as a switching element is formed is defined as a switching region TrA, and a region where the storage capacitor StgC is formed is defined as a storage region StgA.

The transverse electric field type liquid crystal display 100 according to the embodiment of the present invention includes an array substrate 100 having a plurality of pixel electrodes 170 alternately spaced apart from each other and a common electrode 173 and a color filter layer 150, And an opposing substrate 181 and a liquid crystal layer 195 provided with a spacer 102 and spacers 188 and 189, respectively.

4) extending in one direction is formed on the lower array substrate 102, and a common wiring (109 in Fig. 4) is formed in parallel to the gate wiring (103 in Fig. 4) Respectively.

At this time, corresponding to the switching region TrA, the gate wiring (103 in FIG. 4) itself forms a gate electrode 105 in a part of the region.

In the respective pixel regions P, an outermost common electrode 116 is formed which is branched from the common wiring (109 in Fig. 4) and is adjacent to the data wiring 130 and the outermost common electrode 116. In the storage region StgA, (109 in FIG. 4) has a larger width than other regions, thereby forming the first storage electrode 110 itself.

Next, an inorganic insulating material such as silicon oxide (SiO ₂ ) is formed on the entire surface of the gate wiring (103 in FIG. 4), the gate electrode 105, the common wiring (109 in FIG. 4) Or a gate insulating film 118 made of silicon nitride (SiNx) is formed.

An active layer 120a made of pure amorphous silicon and an ohmic contact layer 120b made of impurity amorphous silicon and spaced apart from each other are formed in the switching region TrA above the gate insulating layer 118, The semiconductor layer 120 is formed.

A data line 130 is formed on the gate insulating layer 118 to define a pixel region P intersecting the gate line 103 (see FIG. 4). In this example, a semiconductor pattern 121 formed of first and second patterns 121a and 121b made of the same material that constitutes the semiconductor layer 120 is formed under the data line 130 However, such a semiconductor pattern 121 is caused by the manufacturing process and can be omitted.

A source electrode 133 is formed in the switching region TrA so as to branch off from the data line 130 above the semiconductor layer 120. The source electrode 133 is spaced apart from the source electrode 133, Respectively. At this time, the source electrode 133 and the drain electrode 136 are in contact with the ohmic contact layer 120b which are separated from each other.

The gate electrode 105, the gate insulating film 118, the semiconductor layer 120, and the source and drain electrodes 133 and 136, which are sequentially stacked in the switching region TrA, Respectively.

The drain electrode 136 extends to correspond to the first storage electrode 110 above the gate insulating layer 118 to form a second storage electrode 138 in the storage region StgA. At this time, the first storage electrode 110, the gate insulating layer 118, and the second storage electrode 138, which are sequentially stacked in the storage region StgA, form a storage capacitor StgC.

Next, a first protection made of an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx) is formed on the data line 130, the source and drain electrodes 133 and 136, and the second storage electrode 138. A layer 140 is formed on the entire surface.

The red, green, and blue color filter patterns 150a, 150b, and 150c are sequentially formed on the first passivation layer 140 in the display area corresponding to the pixel areas P, A color filter layer 150 is formed.

Next, a second passivation layer 155 made of photo acryl, which is a material having a relatively low dielectric constant, is formed on the color filter layer 150.

The formation of the second passivation layer 155 with photo-acrylic having low dielectric constant characteristics is caused by overlapping with the data line 130 and the conductive pattern 175 formed on the uppermost common electrode 116 And minimizes the influence of the undesired electric field generated by the data line 130 and the outermost common electrode 116 formed in the periphery thereof.

In addition, since photo-acryl has a negative type characteristic that is left at the time of development upon reception of light, when a contact hole or the like is formed in the lower part of the manufacturing process, it is not necessary to perform a separate strip process, This is because it has advantages.

The drain electrode 136 is formed on the color filter layer 150 and the first passivation layer 140 provided below the second passivation layer 155 made of photoacrylic material having a low dielectric constant. And a drain contact hole 157 exposing the second storage electrode (not shown), which is an extended portion of the electrode 136, is formed. In the transverse electric field type liquid crystal display device 100 according to the embodiment of the present invention, the common contact holes provided in the conventional transverse electric field type liquid crystal display device (95 in Fig. 3) in each pixel region P are omitted, It is characterized by being improved.

Next, a lower layer (not shown) made of moly titanium (MoTi), which is an opaque metal material having opaque low resistance characteristics, on the second passivation layer 155 having the drain contact hole 157, Layer structure of an upper layer (not shown) made of any one of tin-oxide (ITO), indium-zinc-oxide (IZO), aluminum-doped zinc-oxide (AZO) The auxiliary common wiring 175 is formed.

At this time, since the auxiliary common wiring 175 is configured to be in contact with the common wiring (109 in Fig. 4) in the non-display area outside the display area, these two elements can be electrically As shown in FIG.

The auxiliary common wiring 175 includes a vertical portion 175a overlapping the data line 130 and the outermost common electrode 116 spaced apart from the data line 130 in correspondence with the boundary of each pixel region P, 4) 103 and a horizontal portion 175b overlapping with the common wiring (109 in FIG. 4) spaced apart from each other. The data line 130 and the outermost common electrode 116 form a lattice- And a black matrix for suppressing light leakage generated in the spacing region between the gate wiring (103 in FIG. 4) and the common wiring (109 in FIG. 4).

A pixel pattern 169 is formed on the second passivation layer 155 to contact the second storage electrode 138 connected to the drain electrode 136 through the drain contact hole 157.

In each pixel region P, a plurality of central portions in the form of a bar having a bilayer structure branching from the horizontal portion 175b of the auxiliary common wiring 175 are formed on the upper portion of the second protective layer 155 And an electrode 173 is formed inside the outermost common electrode 116 at a predetermined interval.

A plurality of central common electrodes (not shown) in the shape of a bar are formed in the pixel region P above the second passivation layer 155 and branching from the pixel pattern 169 and inside the outermost common electrode 116 And a plurality of bar-shaped pixel electrodes 170 are formed alternately.

At this time, the plurality of pixel electrodes 170 and the central common electrode 173 are formed of a lower layer 170a, 173a made of moly titanium (MoTi), a transparent conductive material such as indium-tin-oxide (ITO), indium- Layer structure composed of an upper layer 170b and a lower layer 173b made of copper nitride (CuNx), which is either low-reflectivity opaque metal material, IZO, or aluminum-doped zinc-oxide (AZO).

When the double-layer structure pixel electrode 170 and the central common electrode 173 are formed in each pixel region P, the reflectance due to external light can be reduced to 39% or less.

When two or more materials have a specific thickness and a material layer of a bilayer structure is formed, each material layer has a difference in refractive indices therein, and the light reflected from the surface of each material layer due to the refractive index and thickness difference is canceled It is possible to reduce the intensity of the finally reflected light due to the anti-reflection coating effect that causes the interference, and the reflectance of the external light can be reduced to 39% or less by this phenomenon.

On the other hand, when the upper layer is made of copper (CuNx), there is no effect of the anti-reflection coating described above, but since it has a low reflection characteristic, it has a reflectance of 39% or less with respect to external light. At this time, the reason why the lower layer of moly titanium is formed below the upper layer made of copper nitride (CuNx) is that the adhesion property of the second protective layer 155 made of copper nitride (CuNx) and photoacryl is very poor, And a lower layer of copper nitride (CuNx) is formed.

The pixel electrode 170, the central common electrode 173 and the outermost common electrode 116 having such a bilayer structure may have a linear bar shape in each pixel region P, Or may have a bar shape symmetrically deflected with respect to a central portion of each pixel region P. [

In the case where the pixel electrode 170 and the common electrodes 116 and 173 are formed in a bar shape symmetrically bent in each pixel region P, each pixel region P has a double domain, And has an effect of suppressing the generation of color difference due to the change.

On the other hand, a gap forming spacer 188 having a columnar first height corresponding to the boundary of the pixel region P is formed on the counter substrate 181 corresponding to the array substrate 102 having such a configuration, Spaced apart from each other, and at the same time, a pressure-preventing spacer 189 having a second height smaller than the first height is formed at a predetermined interval.

The liquid crystal layer 195 is resumed between the array substrate 102 and the counter substrate 181 having such a configuration and the end of the gap forming spacer 188 is positioned at the top of the array substrate 102 And are joined together.

At this time, in order to keep the array substrate 102 and the counter substrate 181 adhered to each other to maintain the state of the panel, a seal pattern (not shown) serving as an adhesive in the form of surrounding the liquid crystal layer 195 A transverse electric field type liquid crystal display device 100 according to an embodiment of the present invention is completed.

In the transverse electric field type liquid crystal display device 100 according to the embodiment of the present invention having such a configuration, the aperture ratio can be improved by omitting the black matrix, and the number of mask steps can be reduced at the same time. The manufacturing cost can be reduced.

In addition, the common contact holes are omitted in each pixel region P, thereby further improving the aperture ratio.

A central portion common electrode 173 having a bar shape formed on the second passivation layer 155 and the pixel electrode 170 may be formed of an opaque metal material, a transparent conductive material, or a double layer structure of copper nitride (CuNx) So that the reflectance by the external light is reduced to 39% or less, thereby suppressing the occurrence of rainbow stains and improving the ambient contrast ratio.

In addition, the data line 130, the center common electrode 173 and the pixel electrode 170 in the form of a bar formed in parallel thereto form a line-symmetric structure in which the pixel electrode 170 is bent upward and downward in each pixel region P, So that chrominance due to a change in the viewing angle is suppressed.

100: transverse electric field type liquid crystal display device 103: gate wiring
105: gate electrode 109: common wiring
110: first storage electrode 116: outermost common electrode
130: data line 133: source electrode
136: drain electrode 138: second storage electrode
157: drain contact hole 169: pixel pattern
170: pixel electrode 173: central common electrode
175: auxiliary common wiring
175a, 175b: a vertical portion (of the auxiliary common wiring) and a horizontal portion
P: pixel region StgC: storage capacitor
Tr: thin film transistor

Claims (10)

A first substrate and a second substrate which are defined by a display region and a non-display region and are bonded to each other with a liquid crystal layer interposed therebetween;
Gate lines and data lines formed to define a plurality of pixel regions intersecting with each other in the display region of the inner surface of the first substrate;
A common wiring formed on an inner surface of the first substrate so as to be parallel to the gate wiring;
A thin film transistor connected to the gate wiring and the data wiring and formed in each of the pixel regions;
A color filter layer formed on the thin film transistor and having red, green, and blue color filter patterns sequentially repeating over the display region;
A first protective layer formed on the color filter layer;
And a vertical portion formed to overlap with the data line on the first protective layer and a horizontal portion overlapping the gate line and the common line, An auxiliary common wiring;
A plurality of bar-shaped central common electrodes branched from the horizontal portion of the auxiliary common wiring in each pixel region above the first protective layer;
And a plurality of bar-shaped pixel electrodes connected to the thin film transistors on the first passivation layer and alternating with the plurality of central common electrodes in each of the pixel regions,
Wherein an outermost common electrode branched from the common wiring and adjacent to the data wiring is formed in each of the pixel regions in the first substrate, the vertical portion of the auxiliary common wiring also overlaps with the outermost common electrode Lt; / RTI &
Wherein a vertical portion of the auxiliary common wiring covers a spacing region between the data wiring and the outermost common electrode and a horizontal portion of the auxiliary common wiring covers a gap region between the common wiring and the gate wiring, Electric field type liquid crystal display device.
delete The method according to claim 1,
A spacer formed on the inner surface of the second substrate in a columnar shape having a first height corresponding to a boundary of the pixel region and spaced apart from the spacer by a predetermined distance, a spacer having a second height lower than the first height, Type liquid crystal display device according to the present invention.
The method according to claim 1,
Wherein the auxiliary common wiring, the pixel electrode, and the central common electrode have a double layer structure of a lower layer made of an opaque metal material and an upper layer made of a transparent conductive material or copper nitride (CuNx).
5. The method of claim 4,
Wherein the transparent conductive material is any one of indium-tin-oxide (ITO), indium-zinc-oxide (IZO), and aluminum-doped zinc-oxide (AZO).
The method according to claim 1,
The common wiring may be a first storage electrode, and the drain electrode of the thin film transistor may be formed to overlap the first storage electrode to form a second storage electrode. The first storage electrode, the gate insulating film, And the electrode is a storage capacitor.
The method according to claim 1,
A second protective layer made of an inorganic insulating material is formed on the entire surface of the first substrate between the thin film transistor and the color filter layer,
In each pixel region, a drain contact hole is formed in the first passivation layer, the color filter layer, and the second passivation layer to expose the drain electrode of the thin film transistor,
And the pixel electrode is in contact with the drain electrode of the thin film transistor through the drain contact hole.
The method according to claim 1,
And a pixel pattern for connecting all the ends of the bar-shaped pixel electrode is formed on the first passivation layer in each of the pixel regions.
The method according to claim 1,
Wherein the data line, the pixel electrode, the outermost electrode, and the central common electrode are symmetrically bent with respect to a central portion of the pixel region, so that each pixel region forms a double domain.
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