KR20070044918A - Liquid display panel and method for manufacturing the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal panel and a method of manufacturing the same, which can prevent the transverse electric field formed in the liquid crystal layer from being distorted by removing static electricity generated from the inside as well as the outside of the liquid crystal panel. Upper and lower substrates, recesses formed by etching non-display areas of the upper substrates, conductive pads formed on the non-display areas of the lower substrates to correspond to the recesses, and the lower substrates. And a conductive tape formed by connecting a conductive pad formed in the non-display area of the substrate to a recess formed in the upper substrate.

LCD panel, static electricity, conductive tape, conductive pad, recess

Description

Liquid crystal panel and method for manufacturing the same

1 is a schematic perspective view showing a general liquid crystal panel

Figure 2a is a plan view showing a conventional IPS mode liquid crystal display device

FIG. 2B is a cross-sectional view illustrating the IPS mode liquid crystal display device taken along the line II ′ of FIG. 2A.

3A and 3B are plan views schematically illustrating structures of an upper substrate and a lower substrate of a liquid crystal panel according to an exemplary embodiment of the present invention.

4 is a plan view illustrating a thin film transistor array formed on a display area of a lower substrate of FIG. 3B.

5 is a cross-sectional view showing a liquid crystal panel according to the present invention.

6A to 6D are process plan views illustrating a method of manufacturing a liquid crystal panel according to the present invention.

Explanation of symbols for the main parts of the drawings

200: upper substrate 210: recessed portion

300: lower substrate 310: ground wiring

320: conductive pad 400: conductive tape

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal panel and a method of manufacturing the same, which can effectively discharge static electricity generated inside and outside the liquid crystal panel.

Recently, with the development of various portable electronic devices such as mobile phones, PDAs, and notebook computers, there is a growing demand for flat panel display devices for light and thin applications.

Such flat panel displays are being actively researched, such as LCD (Liquid Crystal Display), PDP (Plasma Display Panel), FED (Field Emission Display), and VFD (Vacuum Fluorescent Display). Liquid crystal displays (LCDs) are in the spotlight for reasons of implementation.

Such liquid crystal display devices have various display modes according to the arrangement of liquid crystal molecules. However, TN mode liquid crystal display devices are mainly used because of the advantages of easy monochrome display, fast response speed, and low driving voltage.

In such a TN mode liquid crystal display, liquid crystal molecules oriented horizontally with respect to the substrate are almost perpendicular to the substrate when a voltage is applied. Therefore, there is a problem that the viewing angle is narrowed upon application of voltage due to the refractive anisotropy of the liquid crystal molecules.

In order to solve this viewing angle problem, liquid crystal displays of various modes having a wide viewing angle characteristic have recently been proposed, but among them, the liquid crystal display of the lateral field mode (In Plane Switching Mode) is applied to actual production. It is produced.

The IPS mode liquid crystal display device aligns liquid crystal molecules in a plane by forming at least one pair of electrodes arranged in parallel in a pixel to form a transverse electric field substantially parallel to the substrate.

1 is a schematic perspective view showing a general liquid crystal panel.

As shown in FIG. 1, the liquid crystal panel includes a color filter array substrate 10 and a thin film transistor array substrate 20 bonded together with a liquid crystal 8 interposed therebetween.

In this case, the liquid crystal 8 is rotated in response to an electric field applied to the liquid crystal 8 to adjust the amount of light transmitted through the thin film transistor array substrate 20.

In addition, the thin film transistor array substrate 20 is formed such that the data line 18 and the gate line 12 are insulated from each other with a gate insulating film interposed therebetween on the front surface of the lower substrate 21, and the TFTs are formed at the intersections thereof. 16 is formed. The TFT 16 consists of a drain electrode facing the source electrode with a channel portion including a gate electrode connected to the gate line 12, a source electrode connected to the data line 18, an active layer, and an ohmic contact layer interposed therebetween.

In addition, the TFT 16 is connected to the pixel electrode 14 through a contact hole penetrating the protective film.

The TFT 16 selectively supplies the data signal from the data line 18 to the pixel electrode 14 in response to the gate signal from the gate line 12.

The pixel electrode 14 is positioned in a cell region divided by the data line 18 and the gate line 12 and is made of a transparent conductive material having high light transmittance. The pixel electrode 14 generates a potential difference from the common electrode 6 by the data signal supplied via the drain electrode.

Due to this potential difference, the liquid crystal 8 located between the lower substrate 21 and the upper substrate 1 is rotated by the dielectric anisotropy.

Accordingly, light supplied from the light source via the pixel electrode 14 is transmitted toward the upper substrate 1.

In addition, the color filter array substrate 10 includes a color filter 4 and a common electrode 6 formed on the rear surface of the upper substrate 1. The color filter 4 has a color filter layer of red (R), green (G), and blue (B) colors arranged in a stripe shape to transmit light of a specific wavelength band, thereby enabling color display.

The black matrix 2 is formed between the color filters 4 of the adjacent color to absorb the light incident from the adjacent cells, thereby preventing the lowering of the contrast.

Hereinafter, a liquid crystal display according to the related art will be described with reference to the accompanying drawings.

FIG. 2A is a plan view illustrating a conventional IPS mode liquid crystal display device, and FIG. 2B is a cross-sectional view illustrating an IPS mode liquid crystal display device taken along line II ′ of FIG. 2A.

As shown in FIG. 2A, the liquid crystal panel 30 is provided with a gate line 31 and a data line 32 defining pixel regions while crossing each other at regular intervals. Although only the (n, m) th pixel region is shown in the drawing, the actual liquid crystal panel 30 includes N (> n) and M (> m) gate lines 31 and data lines 32, respectively. ) To form N × M pixels over the entire liquid crystal panel 30.

The thin film transistor 40 is formed at the intersection of the gate line 31 and the data line 32 in the pixel region.

The thin film transistor 40 is a gate electrode 41 to which a scan signal is applied from the gate line 31 and a semiconductor formed on the gate electrode 41 and activated as a scan signal is applied to form a channel layer. The liquid crystal layer is formed of a layer 42 and a source electrode 43 and a drain electrode 44 formed on the semiconductor layer 42 and to which an image signal is applied through the data line 32. To apply.

In the pixel area, a plurality of common electrodes 33 and pixel electrodes 34 arranged substantially parallel to the data line 32 are disposed.

In addition, a common line 35 connected to the common electrode 33 is disposed in the middle of the pixel region, and a pixel electrode line 36 connected to the pixel electrode 34 is disposed on the common line 35. And overlaps with the common line 35.

A storage capacitance is formed by the overlap of the common line 35 and the pixel electrode line 36.

In the IPS mode liquid crystal panel configured as described above, the liquid crystal molecules are aligned substantially in parallel with the common electrode 33 and the pixel electrode 34.

When the thin film transistor 40 is operated to apply a signal to the pixel electrode 34, a transverse electric field substantially parallel to the liquid crystal panel 30 is generated between the common electrode 33 and the pixel electrode 34. Since the liquid crystal molecules rotate on the same plane along the transverse electric field, gray level inversion due to the refractive anisotropy of the liquid crystal molecules can be prevented.

The conventional IPS mode liquid crystal panel having the above structure will be described in more detail with reference to the cross-sectional view of FIG. 1B.

As shown in FIG. 2B, a gate electrode 41 is formed on the first substrate 50, and a gate insulating layer 45 is stacked over the entire first substrate 50.

The semiconductor layer 42 is formed on the gate insulating layer 45, and a source electrode 43 and a drain electrode 44 are formed thereon.

In addition, a passivation layer 46 is formed over the entire first substrate 50.

In addition, a plurality of common electrodes 33 are formed on the first substrate 50, and a pixel electrode 35 and a data line 32 are formed on the gate insulating layer 45 to form the common electrode 33 and the pixel. The transverse electric field is generated between the electrodes 34.

The black matrix 62 and the color filter layer 64 are formed on the second substrate 60. The black matrix 62 is to prevent light leakage into an area where the liquid crystal molecules do not operate. As shown in the drawing, the black matrix 62 is between the region of the thin film transistor 40 and between the pixel and the pixel (ie, the gate line and the data line). Area).

In addition, the color filter layer 64 is composed of R (Red), B (Blue), G (Green) to implement the actual color. The liquid crystal layer 70 is formed between the first substrate 50 and the second substrate 60 to complete the liquid crystal panel 30.

In the IPS mode liquid crystal display device, a transverse electric field parallel to the liquid crystal panel 30 is generated by the common electrode 33 and the pixel electrode 34, and the liquid crystal molecules rotate on the same plane along the transverse electric field. . Therefore, the gray scale inversion due to the refractive anisotropy of the liquid crystal molecules can be prevented, and as a result, the viewing angle can be improved.

However, in the IPS mode liquid crystal display device as described above, when an electric field perpendicular to the liquid crystal panel 30 (the direction from the first substrate 50 to the second substrate 60) is generated, the transverse electric field of the liquid crystal layer 70 is generated. Influence on the liquid crystal layer 70 prevents the formation of a transverse electric field that is completely parallel to the liquid crystal panel 30.

That is, the transverse electric field applied to the liquid crystal layer 70 is distorted. When the lateral electric field is not parallel to the liquid crystal panel 30 as described above, the liquid crystal molecules of the liquid crystal layer 70 do not rotate on the same plane, thereby causing a defect in the liquid crystal display device.

Currently, studies on the cause of the electric field perpendicular to the liquid crystal panel 30 are being actively conducted. Among various causes, the second substrate 60 is formed on the rear surface (the surface exposed to the outside without contacting the liquid crystal layer). It is known that vertical electric fields are generated by static electricity.

Such static electricity is generated by contact with a human hand after completion of the liquid crystal panel 30.

In order to remove such static electricity, in the conventional IPS mode liquid crystal panel, as illustrated in FIG. 1B, the static electricity removing conductive layer 80 made of a transparent conductive material such as indium tin oxide (ITO) is formed on the back surface of the second substrate 60. ) Was formed.

Although not shown in the figure, a conductive tape is attached to the conductive layer 80 to electrically connect the outer case and the liquid crystal panel 30 to which the liquid crystal panel 1 is assembled. That is, the conductive layer 80 is grounded by the conductive tape to remove the static electricity generated on the back surface of the second substrate 60.

However, the static electricity is not substantially completely removed by the static electricity removing conductive layer 80 as described above. This is because static electricity is not only generated on the back surface of the second substrate 60 but also on the inner surface of the second substrate 60 (the surface in contact with the liquid crystal layer).

The static electricity on the inner surface of the second substrate 60 is caused by various factors, but the external environment during the process is one of the main causes.

As described above, since the static electricity of the liquid crystal panel 30 is generated not only on the rear surface of the second substrate 60 but also on the inner surface, only the static electricity removal conductive layer 80 formed on the rear surface of the second substrate 60 completely removes the static electricity. It was impossible to do.

The present invention has been made to solve the above and the conventional problems, the liquid crystal panel and method for manufacturing the liquid crystal panel which can prevent the transverse electric field formed in the liquid crystal layer is distorted by eliminating static electricity generated from the inside as well as the outside of the liquid crystal panel. The purpose is to provide.

The liquid crystal panel according to the present invention for achieving the above object includes an upper substrate and a lower substrate defined as a display area and a non-display area, a recess formed by etching a predetermined portion of the non-display area of the upper substrate, And a conductive tape formed in the non-display area of the lower substrate so as to correspond to the recess portion, and a conductive tape formed by connecting the conductive pad formed in the non-display area of the lower substrate and the recess formed in the upper substrate. It features.

In addition, the manufacturing method of the liquid crystal panel according to the present invention for achieving the above object is a step of forming a conductive pad to tie the ground wiring formed in the non-display area of the lower substrate defined by the display area and the non-display area in one place And etching a predetermined portion of the non-display area of the upper substrate defined as the display area and the non-display area to form a recessed portion corresponding to the conductive pad formed on the lower substrate, and forming the lower substrate and the lower portion on which the conductive pad is formed. And forming a conductive tape connecting the recess portion and the upper substrate to correspond to each other, and forming a conductive tape connecting the conductive pad and the recess portion to each other.

Hereinafter, a liquid crystal panel and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings.

3A and 3B are plan views schematically illustrating structures of an upper substrate and a lower substrate of a liquid crystal panel according to an exemplary embodiment of the present invention.

As shown in FIGS. 3A and 3B, a cell gap is fixed between the lower substrate 300 and the upper substrate 200 and the upper substrate 200 and the lower substrate 300 bonded to each other with a predetermined gap. And a liquid crystal filled in the liquid crystal space provided by the spacer.

As illustrated in FIG. 3A, the upper substrate 200 is divided into an upper display region 170a on which a color filter array is formed and an upper non-display region 170b positioned outside the upper display region 170a.

In addition, the upper display area 170a includes a color filter, a black matrix for preventing light leakage, and an alignment layer coated thereon for liquid crystal alignment.

In addition, a predetermined portion of the upper non-display area 170b of the upper substrate 200 is etched to form a recess 210 on a side surface thereof.

In addition, as shown in FIG. 3B, the lower substrate 300 may include a lower display area 180a in which a thin film transistor array is formed and a lower non-display area 180b positioned outside the lower display area 180a. Equipped.

The lower display area 180a is formed to overlap the upper display area 170a, and the lower non-display area 180b is formed to overlap the upper non-display area 170b.

Meanwhile, although the upper display area 170a and the lower display area 180a have the same size, the lower non-display area 180b is formed to have a wider width than the non-display area 170b.

In addition, a plurality of ground lines 310 formed at an edge of the lower non-display area 180b and a conductive pad 320 connecting the plurality of ground lines 310 are provided.

Here, the recess 210 formed on the upper substrate 200 corresponds to the conductive pad 320 formed on the lower substrate 300.

Here, the conductive pad 320 is formed in a form in which a ground inside the thin film transistor (TFT) array is bundled together.

Meanwhile, the conductive pad 320 is coated on the edge of the non-display area when the electrode material is completely coated on a substrate and then patterned, for example, when forming a gate line or a data line, a common electrode, and a pixel electrode. The material is left without removing it to form a relatively large area ratio.

In addition, the conductive pad 320 may be formed of a conductive metal, indium tin oxide (ITO), tin oxide (TO), indium zinc oxide (IZO), or indium tin. Zinc oxide (Indium Tin Zinc Oxide: ITZO) and the like are used.

4 is a plan view illustrating a thin film transistor array formed in a display area of a lower substrate of FIG. 3B.

As shown in FIG. 4, the lower display area 180a of the lower substrate 300 intersects each other to define a gate line 301 and a data line 302, and the gate line 301. ) And a pixel electrode formed to form a horizontal electric field in the pixel region P defined by the intersection of the thin film transistor 303 formed at each intersection of the data line 302 and the gate line 301 and the data line 302. 304 and the common electrode 305, and a common line 316 connected to the common electrode 305.

Here, the gate line 301 supplies a gate signal to the gate electrode 308 of the thin film transistor 303, and the data line 302 uses the pixel electrode (312) through the drain electrode 312 of the thin film transistor 303. The pixel signal is supplied to 304.

In addition, the common line 316 is formed in parallel with the gate line 301 with the pixel region therebetween, and supplies a reference voltage for driving the liquid crystal to the common electrode 305.

In addition, the thin film transistor 303 keeps the pixel signal of the data line 302 charged and maintained in the pixel electrode 304 in response to the gate signal of the gate line 301.

To this end, the thin film transistor 303 is connected to the gate electrode 308 connected to the gate line 301, the source electrode 311 connected to the data line 302, and the pixel electrode 304. A drain electrode 312 is provided.

In addition, the pixel electrode 304 is formed in the pixel region P by being connected to the drain electrode 312 of the thin film transistor 303 through a contact hole 313 penetrating a protective film (not shown).

In particular, the pixel electrode 304 is connected to the drain electrode 312 and is parallel to the adjacent gate line 301, and is formed in parallel with the horizontal portion 304A and is parallel to the common electrode 305. It is provided with a finger portion 304C.

In addition, the common electrode 305 is connected to the common line 316 and is formed in the pixel area P.

In particular, the common electrode 305 is formed parallel to the finger portion 304C of the pixel electrode 304 in the pixel region P.

Accordingly, a horizontal electric field is formed between the pixel electrode 304 supplied with the pixel signal through the thin film transistor 303 and the common electrode 305 supplied with the reference voltage through the common line 316.

In particular, a horizontal electric field is formed between the finger portion 304C of the pixel electrode 304 and the common electrode 305.

The horizontal electric field causes liquid crystal molecules arranged in the horizontal direction between the lower substrate and the upper substrate to rotate by dielectric anisotropy.

According to the degree of rotation of the liquid crystal molecules, the light transmittance passing through the pixel region P is changed, thereby realizing an image.

5 is a cross-sectional view showing a liquid crystal panel according to the present invention.

As shown in FIG. 5, a recess part formed by etching the upper substrate 200 and the lower substrate 300 defined as the display area and the non-display area, and a non-display area of the upper substrate 200 by a predetermined portion ( 210, a conductive pad 320 formed in the non-display area of the lower substrate 300 to correspond to the recess 210, and a conductive pad 320 formed in the non-display area of the lower substrate 300. ) And a conductive tape 400 formed by connecting the recess 210 formed on the upper substrate 200.

On the other hand, the liquid crystal panel configured as described above is accommodated in the support main is not shown and including the edge of the liquid crystal panel is fixed to the support main through the top case.

That is, when the conductive tape 400 is in contact with the top case, not only the static electricity generated inside the liquid crystal panel but also the static electricity generated from the outside may be effectively discharged to the outside.

6A to 6D are process plan views illustrating a method of manufacturing a liquid crystal panel according to the present invention.

As shown in FIG. 6A, a conductive pad 320 is formed to tie the ground wiring 310 formed in the non-display area of the lower substrate 300 defined as the display area and the non-display area at one place.

As shown in FIG. 6B, a predetermined portion of the non-display area of the upper substrate 200 defined as the display area and the non-display area is etched so as to correspond to the conductive pad 320 formed on the lower substrate 300. The part 210 is formed.

As illustrated in FIG. 6C, the lower substrate 300 on which the conductive pad 320 is formed, the recess 210, and the upper substrate 200 formed on each other correspond to each other and are bonded to each other.

As shown in FIG. 6D, the conductive pad 320 and the recess 210 are connected by using a conductive tape 400.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

As described above, the liquid crystal panel and its manufacturing method according to the present invention have the following effects.

That is, by removing a portion of the non-display area of the upper substrate to form a recess and connecting the ground line and the conductive tape of the lower substrate to the liquid crystal layer by effectively dissipating static electricity generated not only from the outside but also from the inside to the outside. The transverse electric field formed can be prevented from being distorted.

Claims (3)

An upper substrate and a lower substrate defined by a display area and a non-display area, A recess formed by etching a predetermined portion of the non-display area of the upper substrate; Conductive pads formed in the non-display area of the lower substrate to correspond to the recesses; And a conductive tape formed by connecting a conductive pad formed in the non-display area of the lower substrate and a recess formed in the upper substrate. The method of claim 1, wherein the conductive pad is a conductive metal, Indium Tin Oxide (ITO), Tin Oxide (TO), Indium Zinc Oxide (IZO) or Indium Tin Zinc Oxide (Indium Tin Zinc Oxide: ITZO) The liquid crystal panel, characterized in that made of any one. Forming a conductive pad that binds the ground wirings formed in the non-display area of the lower substrate defined by the display area and the non-display area in one place; Etching a predetermined portion of the non-display area of the upper substrate defined as the display area and the non-display area to form a recessed portion corresponding to the conductive pad formed on the lower substrate; Bonding the lower substrate on which the conductive pad is formed, the recess portion, and the upper substrate formed to correspond to each other; And forming a conductive tape connecting the conductive pad and the recess to each other.

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