KR100499577B1 - Trans-reflective liquid crystal display device and method for fabricating the same - Google Patents

Abstract

It is an object of the present invention to provide a reflective transmissive liquid crystal display device and a method of manufacturing the same, which can improve the process reliability when etching the reflective metal, improve the reflection efficiency, and solve the problem of deterioration of the uneven pattern composed of photoacryl. A reflective transmissive liquid crystal display device comprising: a plurality of gate lines and data lines in which a pixel area is defined as a reflective area and a transmissive area, the pixel area being alternatingly disposed to define a pixel area; A thin film transistor formed at an intersection of the gate line and the data line; A gate pad and a source pad having first and second holes at one end of the gate line and the data line, the inner side of the gate line and the source line being separated from each other; A transmission electrode connected to the drain electrode of the thin film transistor and formed in the pixel region; A gate pad terminal and a source pad terminal in contact with the gate pad and the source pad through the first and second holes; An interlayer insulating film formed on the substrate including the transmissive electrode to surround side surfaces of the gate pad and the source pad; An uneven pattern formed on the reflective region; It is characterized by including a reflective electrode formed on the reflective region including the uneven pattern so that a portion of the transmissive electrode is exposed.

Description

Reflective type liquid crystal display device and manufacturing method therefor {TRANS-REFLECTIVE LIQUID CRYSTAL DISPLAY DEVICE AND METHOD FOR FABRICATING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a liquid crystal display device, and more particularly, to a reflective liquid crystal display device and a method for manufacturing the same, which can selectively use a reflection mode and a transmission mode.

In general, a liquid crystal display device may be classified into a transmissive liquid crystal display device using a backlight as a light source and a reflective liquid crystal display device using natural light and artificial light without using the backlight as a light source.

In this case, the transmissive liquid crystal display uses a backlight as a light source to realize a bright image even in a dark external environment. However, there is a problem that can not be used in bright places, the power consumption is large.

On the other hand, since the reflective liquid crystal display does not use a backlight, power consumption can be reduced, but there is a limitation that it cannot be used when the external natural light is dark.

As an alternative to overcome these limitations, a reflective liquid crystal display device is provided.

Such a transflective liquid crystal display device has a function of a transmissive liquid crystal display device and a reflective liquid crystal display device by simultaneously providing a reflection unit and a transmissive unit in a unit pixel area, and includes backlight light and external natural light or artificial light. Since all light sources can be used, there is an advantage in that power consumption is reduced without being restricted by the surrounding environment.

On the other hand, the liquid crystal display devices constitute an additional storage capacitor to assist the charge holding ability of the liquid crystal.

Among the structures for forming the storage capacitor, the structure in which the capacitor is formed between the front gate wiring and the pixel electrode is called a storage on gate structure.

The storage capacitor maintains the voltage charged in the liquid crystal capacitor in the turn-off period of the corresponding thin film transistor.

Accordingly, leakage current is prevented from being generated through the liquid crystal capacitor in the turn-off period of the thin film transistor, and deterioration in image quality due to flicker is solved.

Hereinafter, a general reflective transmissive liquid crystal display device will be described with reference to the drawings.

FIG. 1 is an exploded perspective view showing a general reflective transmissive color liquid crystal display device.

As shown in FIG. 1, the general reflective transmissive liquid crystal display 11 includes a color filter 17 including a black matrix 16 and an upper substrate 15 having a transparent common electrode 13 formed on the color filter. And a pixel electrode 19 having a transmissive portion A and a reflecting portion C formed at the same time in the pixel region P and the pixel region, and a lower substrate 21 having a switching element T and array wiring formed thereon. The liquid crystal 23 is filled between the substrate 15 and the lower substrate 21.

The lower substrate 21 is also referred to as a TFT array substrate, and the thin film transistor T, which is a switching element, is positioned in a matrix type, and includes a gate wiring 25 and a data wiring 27 passing through the plurality of thin film transistors. ) Is formed.

In this case, the pixel area P is an area where the gate line 25 and the data line 27 cross each other.

The operation characteristics of the reflective liquid crystal display device having such a configuration will be described with reference to FIG.

2 is a cross-sectional view showing a general reflective transmissive liquid crystal display device.

As shown in FIG. 2, the schematic reflection-transmissive liquid crystal display device 11 includes an upper substrate 15 having the common electrode 13 formed thereon, a reflection electrode 19b including a transmission hole A, and a transmission electrode 19a. ) A lower substrate 21 having a pixel electrode 19 formed of a pixel electrode, a liquid crystal 23 filled between the upper substrate 15 and the lower substrate 21, and a lower substrate 21 positioned below the lower substrate 21. The backlight 41 is comprised.

When the reflective liquid crystal display device 11 having such a configuration is used in a reflective mode, most of the light is used as an external natural light source or an artificial light source.

The operation of the liquid crystal display device in the reflection mode and the transmission mode will be described with reference to the above-described configuration.

In the reflective mode, the liquid crystal display uses an external natural or artificial light source, and the light B incident on the upper substrate 15 of the liquid crystal display is reflected by the reflective electrode 19b to reflect the light. Passes through the liquid crystal 23 arranged by the electric field of the electrode and the common electrode 13, the amount of light (B) passing through the liquid crystal is adjusted according to the arrangement of the liquid crystal 23 to display an image (image) Will be implemented.

On the contrary, when operating in the transmission mode, the light source uses the light F of the backlight 41 positioned below the lower substrate 21. Light emitted from the backlight 41 enters the liquid crystal 23 through the transparent electrode 19a and is arranged by an electric field of the transparent electrode 19a and the common electrode 13 below the through hole. By adjusting the amount of light incident from the lower backlight 41 by the liquid crystal 23 is implemented an image.

Hereinafter, a reflective transmissive liquid crystal display device and a method of manufacturing the same according to the related art will be described with reference to the accompanying drawings.

Generally, a liquid crystal display device includes a thin film transistor array substrate called a lower substrate, a color filter substrate called an upper substrate, and a liquid crystal formed between the two substrates. The following description relates to a thin film transistor array substrate which is a lower substrate.

Hereinafter, a reflective transmissive liquid crystal display device and a manufacturing method thereof will be described.

3 and 4 are plan and structural cross-sectional views of a conventional transflective liquid crystal display device.

5A through 5C are stepwise plan views illustrating a conventional method of manufacturing a transflective liquid crystal display device by enlarging pixels on an array substrate, and FIGS. 6A through 6C illustrate I-I 'and II in FIGS. 5A through 5C. The process cross-sectional view which cuts along -II ', III-III' and IV-IV 'and shows in order of process.

The prior art is a reflective transmissive liquid crystal display device manufactured by applying an uneven pattern to a reflector. As illustrated in FIGS. 3 and 4, a gate pad 51a is formed in one region on a transparent substrate 50. The gate line 51 extends from the gate pad 51a and is arranged in parallel in one direction, and the gate electrode 51b protrudes from one side of the gate line 51, and is integrated with the front gate line. The storage lower electrode 51c is formed at the position.

A gate insulating film 52 is formed on the substrate 50 including the gate line 51, the gate electrode 51b, and the storage lower electrode 51c to electrically insulate the upper layer from the gate electrode 51b. An active layer 53 is formed on the upper gate insulating film 52.

At this time, the active layer 53 is composed of an amorphous silicon layer.

An ohmic contact layer 53a made of amorphous silicon doped is formed on the active layer 53 except for the channel region.

There is a data line 54 intersecting with the gate line 51 to define a pixel region. The source electrode 54b protrudes in one direction from the data line 54 and overlaps one side of the active layer 53. There is a drain electrode 54c spaced apart from the source electrode 54b and overlapping with the other side of the active layer 53.

There is a storage upper electrode 54d formed integrally with the drain electrode 54c and extending to an upper portion of the storage lower electrode 51c formed in a front gate line.

A source pad 54a is formed at one end of the data line 54 to occupy a predetermined area.

The first passivation layer 55 is formed on the entire surface of the substrate 50 including the drain electrode 54c and the storage upper electrode 54d.

In this case, the first passivation layer 55a may include the first, second, and third contact holes 56a, 56b, and 56c on the gate pad 51a, the storage upper electrode 54d, and the source pad 54a, respectively. And a through hole 56d in the pixel region.

Convex and concave and convex patterns 55b (parts shown by circles in FIG. 3) are formed on the first passivation film 55a of the reflecting portion (pixel region except for the lower surface of the through hole 56d), and the first passivation film is formed. On the 55a and the uneven pattern 55b, the reflective electrode 57 is formed with curvature.

In this case, the reflective electrode 57 overlaps with the data line 54 defining the pixel area at a predetermined interval.

 A second passivation layer 58 is formed on the entire surface of the substrate 50 except for the lower surfaces of the first, second, and third contact holes 56a, 56b, 56c and the through hole 56d.

A gate pad terminal 59a and a source pad terminal 59b are formed on the first and third contact holes 56a and 56c and the second passivation layer 58 adjacent thereto, and the second contact hole 56b is formed. The transmissive electrode 59c is formed in the pixel region including the transmissive hole 56d through contact with the storage upper electrode 54d.

As in the above configuration, the transmissive electrode 59c is contacted through the storage upper electrode 54d and the second contact hole 56b in the pixel region.

The reflective electrode 57 and the transmissive electrode 59c are combined to form a pixel electrode.

According to the related art, a method of manufacturing a reflective transmissive liquid crystal display device according to the related art is aluminum (Al), molybdenum (Mo), and tungsten (W), which are conductive metals, on the transparent substrate 50 as shown in FIGS. 5A and 6A. And depositing and patterning other conductive alloys to form a predetermined area at an end thereof, the gate pad 51a, the gate line 51 extending in one direction from the gate pad 51a, and the gate line 51 The gate electrode 51b is formed to protrude to a predetermined area.

While forming the gate line 51, a storage lower electrode 51c is formed in the storage capacitor region of the front gate line.

Next, an insulating material such as silicon dioxide (SiO 2) or silicon nitride (SiN x) is deposited on the entire surface of the substrate 50 on which the gate line 51 is formed, and amorphous amorphous silicon (a-Si) and impurities are sequentially contained. Silicon is deposited to form a gate insulating film 52 and a semiconductor layer (amorphous silicon + impurity amorphous silicon).

Thereafter, the semiconductor layer is patterned to form an active layer 53 in an island shape on the gate electrode 51b.

A conductive metal such as molybdenum (Mo), tungsten (W), or chromium (Cr) is deposited and patterned on the entire surface of the substrate 51 on which the active layer 53 is formed.

The patterning process is performed to form a data line 54 that intersects the gate insulating layer 52 therebetween, a source pad 54a at one end of the data line 54, and the gate electrode 51b. The source electrode 54b is formed so as to protrude in one direction to the top of the top and overlap the one side of the active layer 53.

In addition, the data line 54 is formed, and at the same time, the drain electrode 54c is formed to be spaced apart from the source electrode 54b and overlap with the other side of the active layer 53, and the drain electrode 54c The storage upper electrode 54d is formed on the storage lower electrode 51c formed integrally and connected to the front gate line.

Also, the ohmic contact layer 53a is formed on the active layer 53 by etching the impurity amorphous silicon in the channel region using the source electrode 54b and the drain electrode 54c as a mask.

Next, as shown in FIGS. 5B and 6B, an organic insulating material including benzocyclobuten (BCB), photoacryl resin, and the like on the entire surface of the substrate including the storage upper electrode 54d. The first protective film 55a is formed by applying one selected from the group.

Subsequently, an organic material such as photo acryl is applied onto the first passivation layer 55a, and then the organic material is patterned using an embossing technique to a portion corresponding to the reflector. The uneven pattern 55b is formed.

Thereafter, the first passivation layer 55 and the uneven pattern 55b are patterned to form a through hole 56d in the pixel area.

A reflective metal such as AlNd having a low resistance value and excellent reflectance is deposited on the entire surface of the substrate 50 including the transmission hole 56d, the first passivation layer 55a, and the uneven pattern 55b.

Thereafter, the reflective metal is patterned to form a reflective electrode 57 having a bend in the pixel region.

When the reflective metal is patterned, all of the reflective metal on the gate pad 51a and the source pad 54a is removed.

In this case, since the reflective metal is in direct contact with the gate pad 51a and the source pad 54a through the first and third contact holes 56a and 56c, the gate pad 51a and the source pad ( There is a risk of damage to 54a).

The silicon nitride film SiNx is deposited on the substrate 50 including the reflective electrode 57 to form a second passivation layer 58.

Next, the second passivation layer 58, the reflective electrode 57, and the gate insulating layer 52 are etched to form first and second portions on the gate pad 51a, the storage upper electrode 54d, and the source pad 54a, respectively. And third contact holes 56a, 56b, and 56c. In this case, the substrate 50 is exposed in the portion of the through hole 56d.

Next, as shown in FIGS. 5C and 6C, Indium Tin Oxide (ITO) or Indium-Zink- is formed on the entire surface of the substrate 50 on which the source electrode 54b and the drain electrode 54c are formed. A transparent conductive metal such as indium zinc oxide (IZO) is deposited and patterned to form a transmissive electrode 59c in the pixel region so as to be in direct contact with the storage upper electrode 54d formed on the front gate line.

At the same time as forming the reflective electrode 57, a gate pad terminal 59a in contact with the gate pad 51a is formed in the contact hole on the gate pad 51a and the second passivation layer 58 adjacent thereto. The source pad terminal 59b is formed on the contact hole on the source pad 54a and the second passivation layer 58 adjacent thereto to contact the source pad 54a.

In this case, the reflective electrode 57 is formed to overlap the data line 54 by a predetermined interval.

The reflective liquid crystal display device according to the prior art as described above has the following problems.

First, the photoacryl used to form the uneven pattern 55b has a phase transition temperature of about 200 ° C., and thus has poor thermal stability. However, when the second protective film 58 made of a silicon nitride film is subsequently formed, it must proceed at a temperature higher than 200 ° C., causing a problem of deterioration of the properties of the photo acrylic.

In order to prevent such a problem, the deposition temperature of the second protective film 58 made of a silicon nitride film should be lowered to 200 ° C. or less, which causes a problem in that it is difficult to apply to an actual mass production line.

Second, since the reflective electrode 57 is formed below the transmissive electrode 59c, the reflection efficiency is low.

Third, when the reflective metal is patterned, all of the reflective metal on the gate pad 51a and the source pad 54a is removed. In this case, the reflective metal passes through the first and third contact holes 56a and 56c to form the gate pad 51a. ) And direct contact with the source pad 54a, there is a risk that damage occurs to the gate pad 51a and the source pad 54a.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a reflective transmissive liquid crystal display device that can improve the process reliability when etching the reflective metal in the gate pad and the source pad.

Another object of the present invention is to provide a reflective transmissive liquid crystal display device which can improve reflection efficiency by forming a reflective electrode on the transmissive electrode.

Still another object of the present invention is to provide a method of manufacturing a reflective transmissive liquid crystal display device, which can solve the problem of deterioration of an uneven pattern composed of photoacryl.

In the liquid crystal display device of the present invention for achieving the above object, in the liquid crystal display device in which each pixel region is defined as a reflection region and a transmission region, a plurality of gate lines and data lines are arranged to define the pixel region. and; A thin film transistor formed at an intersection of the gate line and the data line; A gate pad and a source pad having first and second holes at one end of the gate line and the data line, the inner side of the gate line and the source line being separated from each other; A transmission electrode connected to the drain electrode of the thin film transistor and formed in the pixel region; A gate pad terminal and a source pad terminal in contact with the gate pad and the source pad through the first and second holes; An interlayer insulating film formed on the substrate including the transmissive electrode to surround side surfaces of the gate pad and the source pad; An uneven pattern formed on the reflective region; And a reflective electrode formed on the reflective region including the uneven pattern so that a part of the transmissive electrode is exposed.

A protective film is further interposed on the interlayer insulating film including the transmissive electrode.

The protective film further includes a lower portion of the transmissive electrode and the interlayer insulating film.

The transmission electrode, the gate pad terminal, and the source pad terminal may be formed of indium tin oxide (ITO), tin oxide (TO), indium zinc oxide (IZO), or indium tin zinc oxide ( It is formed of a transparent conductive metal such as Indium Tin Zinc Oxide (ITZO).

The interlayer insulating film is formed of a silicon nitride film.

The interlayer insulating film extends about 3 μm from side surfaces of the gate pad and the source pad.

An insulating layer having a contact hole is further provided on the drain electrode of the thin film transistor under the transmission electrode, and the transmission electrode is in contact with the drain electrode through the contact hole.

The reflective electrode may be formed to overlap the data line defining a pixel area.

The reflective electrode is characterized by forming a two-layer structure of Mo-Al or Mo-AlNd.

A storage lower electrode formed integrally with the front gate line and a storage upper electrode are further formed on the storage lower electrode with a gate insulating layer interposed therebetween.

The transmissive electrode is directly contacted by overlapping the storage upper electrode and the drain electrode of the thin film transistor.

The drain electrode of the thin film transistor further extends into the pixel region and is connected to the storage upper electrode.

A semiconductor layer occupying a predetermined area is further formed below the source pad, and the second hole is formed so that one region of the semiconductor layer is exposed.

Bonding bumps are further formed to contact the gate pad terminals and the source pad terminals.

A reflective transmissive liquid crystal display device according to an embodiment of the present invention comprises: a liquid crystal display device in which each pixel region is defined as a reflective region and a transmissive region, comprising: a plurality of gate lines and data lines intersecting to define pixel regions; A thin film transistor formed at an intersection of the gate line and the data line; A storage upper electrode of the storage capacitor formed integrally with the drain electrode of the thin film transistor and formed on a front gate line; A gate pad and a source pad having first and second holes at one end of the gate line and the data line, the inner side of the gate line and the source line being separated from each other; A transmission electrode connected to the drain electrode of the thin film transistor and formed in the pixel region; A gate pad terminal and a source pad terminal in contact with the gate pad and the source pad through the first and second holes; An interlayer insulating film formed on the substrate including the transmissive electrode to surround side surfaces of the gate pad and the source pad; A passivation layer provided with a first through hole having an inclined step so that a part of the transmissive electrode is exposed; An uneven pattern formed on the reflective region including the storage upper electrode and the drain electrode; The inclined stepped portion including the uneven pattern, the passivation layer, and a reflective electrode formed in the reflective region on the lower surface of the first through hole adjacent to the inclined step so that the transmissive electrode is exposed with a second through hole. It is characterized by.

The reflective electrode may be in contact with the transmissive electrode at a lower surface of the first transmissive hole extending at an oblique step.

In the method of manufacturing a reflective transmissive liquid crystal display according to the present invention having the above structure, in the method of manufacturing a liquid crystal display device in which each pixel region is defined as a reflective region and a transmissive region, the gate electrode is arranged in one line direction and protrudes on one side thereof. Forming a plurality of gate lines constituting the plurality of gate lines; Forming a gate pad having a first hole at one end of the gate line to isolate an interior of the gate line; Forming a plurality of data lines intersecting the gate line to define a pixel region, a source electrode protruding from the data line, and a drain electrode spaced apart from the source electrode; Forming a source pad having a second hole at one end of the data line to isolate the inside of the source line; Forming a transmissive electrode in the pixel region in contact with the drain electrode; Forming a gate pad terminal and a source pad terminal to contact the gate pad and the source pad through the first and second holes; Forming an interlayer insulating film on the substrate including the transmissive electrode to surround side surfaces of the gate pad and the source pad; Forming a protective film having a transmission hole so that a part of the transmission electrode is exposed; Forming an uneven pattern on the passivation layer of the reflective region; And forming a reflective electrode in the reflective region including the uneven pattern to be in contact with the transmissive electrode.

The interlayer insulating film is formed of a silicon nitride film and extends about 3 μm from the side surfaces of the gate pad and the source pad.

The passivation layer having the transmission hole may further include being formed before forming the transmission electrode.

The protective layer is formed of one selected from the group of organic insulating materials including benzocyclobuten (BCB), photoacryl resin, and the like.

When forming the transmission hole, first and second contact holes are formed in the gate pad terminal and the source pad terminal.

The uneven pattern is formed by applying an embossing technique after coating an organic material such as photo acryl on the protective film.

The reflective electrode is formed to contact the transmission electrode at an edge of the transmission hole.

The reflective electrode is formed by stacking a first metal having a low resistance and a second metal having good reflectivity, wherein the first metal uses Mo, and the second metal uses Al or AlNd.

The transmissive electrode is formed to be in direct contact with both the drain electrode and the storage upper electrode.

Bonding bumps are formed in the first and second contact holes to contact the gate pad terminal and the source pad terminal.

In general, a liquid crystal display device includes a thin film transistor array substrate called a lower substrate, a color filter substrate called an upper substrate, and a liquid crystal formed between the two substrates. The following description relates to a thin film transistor array substrate which is a lower substrate.

Hereinafter, a reflective liquid crystal display device and a method of manufacturing the same will be described with reference to the accompanying drawings.

7 and 8 are a plan view and a structural cross-sectional view of a reflective transmissive liquid crystal display device according to an embodiment of the present invention.

9A to 9C are stepped plan views illustrating a method of manufacturing a reflective transmissive liquid crystal display device according to an exemplary embodiment of the present invention, in which pixels of an array substrate are enlarged, and FIGS. 10A to 10C are V-V of FIGS. 9A to 9C. Process cross-sectional view, cut along ', VI-VI', Ⅶ-Ⅶ 'and Ⅷ-Ⅷ', according to the process sequence.

VV 'is a cross-sectional view of the thin film transistor and the storage capacitor, VI-VI' is a cross-sectional view of the storage capacitor and the through hole, V-V 'is a cross-sectional view of the gate pad, and V-V' is a source. It is a cross section which cut the pad.

The present invention provides a reflective transmission liquid crystal display device having a concave-convex pattern made of photoacryl. As shown in FIGS. 7 and 8, the gate pad 111a and the source pad 114a have first and second holes therein. And a reflective electrode 119a is formed on the transmissive electrode 115 and extends to the sides of the gate pad 111a and the source pad 114a and the gate line 111 before forming the transmissive hole. It is characteristic to form a protective film pattern as much as possible.

Hereinafter, the reflective liquid crystal display of the present invention having the above characteristics will be described in more detail.

As shown in FIG. 7 and FIG. 8, the gate lines 111 are arranged parallel to each other at a predetermined interval on the transparent substrate 110, and a first hole is formed at the end of the gate lines 111. A gate pad 111a is formed and isolated, and there is a gate electrode 111b protruding in one direction from the gate line 111. The gate pad 111b is formed integrally with the front gate line. ) Is formed.

A gate insulating layer 112 is formed on the gate line 111, the gate electrode 111b, and the storage lower electrode 111c to electrically insulate the upper layer. The gate insulating layer 112 is formed on the gate electrode 111b. An active layer 113 is formed on the 112.

In this case, the active layer 113 is formed of an amorphous silicon layer, and an ohmic contact layer 113a formed of a doped amorphous silicon layer is formed on the active layer 113 except for the channel region on the gate electrode 111b.

A data line 114 is formed to cross the gate line 111 to define a pixel region, and a second hole is formed at an end of the data line 114 to form an isolated source pad 114a. The source electrode 114b protrudes in one direction from the data line 114 and overlaps one side of the active layer 113. The source electrode 114b is spaced apart from the source electrode 114b and overlaps the other side of the active layer 113. There is a drain electrode 114c formed.

A semiconductor layer 113a is formed below the source pad 114a to occupy a predetermined area, and the second hole is formed to expose one region of the semiconductor layer 113a.

A storage upper electrode 114d is formed on the storage lower electrode 111c and spaced apart from the drain electrode 114c and formed on a front gate line.

As described above, the thin film transistor is formed in an area where the gate line 111 and the data line 114 cross each other.

In the pixel region, there is a transmissive electrode 115 directly overlapping the storage upper electrode 114d and the drain electrode 114c.

In this case, the transmission electrode 115 is larger than the second transmission hole 117 which will be described later.

When the transparent electrode 115 is in direct contact with the drain electrode 114c and the storage upper electrode 114d as described above, the drain electrode 114c, the transmissive electrode 115, the storage upper electrode 114d, and the transmissive electrode 115 are formed. No separate contact is required between them, simplifying the process.

The gate pad terminal 115a and the source pad terminal 115b are formed on the gate pad 111a and the source pad 114a so as to contact each other through first and second holes.

The transmissive electrode 115, the gate pad terminal 115a, and the source pad terminal 115b are formed of indium tin oxide (ITO), tin oxide (TO), and indium zinc oxide (IZO). ) Or a transparent conductive metal such as indium tin zinc oxide (ITZO).

Although not shown in the drawing, a passivation layer having a contact hole in the drain electrode 114c and the storage upper electrode 114d is further provided below the transmissive electrode 115 so that the transmissive electrode 115 has a drain electrode through the contact hole. It may be in contact with the 114c and the storage upper electrode 114d.

An interlayer insulating film 120 formed of a silicon nitride film is formed on the entire surface of the substrate 110 including the thin film transistor and the pixel region. In this case, the interlayer insulating layer 120 is formed to cover the side surfaces of the gate pad 111a and the source pad 114a on the gate pad terminal 115a and the source pad terminal 115b on the first and second holes. have.

The interlayer insulating layer 120 extends at least 3 μm from the side surfaces of the gate pad 111a and the source pad 114a.

As described above, when the interlayer insulating layer 120 is formed to cover side surfaces of the gate pad 111a and the source pad 114a in the first and second holes, the interlayer insulating layer 120 is transparent when the reflective electrodes of the first and second holes are removed later. The gate pad terminal 115a and the source pad terminal 115b formed of a conductive metal are damaged by an etchant to damage the lower gate pad 111a and the source pad 114a through a pin hole. Can be prevented.

The first passivation layer 116a having first through holes, first and second contact holes 118a and 118b formed on the transmissive electrode 115, the gate pad 111a and the source pad 114a in the pixel area, respectively. Is formed.

Convex and concave patterns 116b (parts shown by circles in FIG. 7) are formed convexly on the first passivation film 116a of the reflecting portion (a pixel region except the lower surface of the through hole).

The through hole is divided into a first through hole and a second through hole. The first through hole refers to a contact hole formed with an inclined step by the first passivation layer 116a, and the second through hole later reflects the electrode 119a. Refers to a region where the transmissive electrode 115 is exposed by.

Therefore, the first through hole has a larger area than the second through hole.

The reflective electrode 119a is bent on the first passivation layer 116a and the concave-convex pattern 116b on the reflector so as to contact the transmissive electrode 115 at a lower surface of the first through hole extending from the inclined stepped portion on the pixel region. It is formed with.

The reflective electrode 119a is formed to overlap the data line 114 defining the pixel area.

The reflective electrode 119a and the transmissive electrode 115 are combined to form a pixel electrode.

The reflective electrode 119a is formed by stacking a first metal having a lower resistance than a single layer structure and a second metal having good reflectivity, wherein the first metal uses Mo, and the second metal uses Al or AlNd. .

The reason why the reflective electrode 119a is formed is because the contact resistance of Mo and the transparent electrode ITO is smaller than that of Al or AlNd when contacting the transparent electrode, and Al, AlNd and ITO are directly Diffusion occurs at the interface and Al2O3 is generated to cause galvanic corrosion problems.

Since the reflective electrode 119a extends to the upper portion of the first passivation layer 116a, the inclined step portion of the first through hole, and the lower surface of the first through hole extending from the inclined step portion, the reflection efficiency can be increased. .

In addition, since the reflective electrode 119a has irregularities and the reflective electrode 119a is formed on the transmission electrode 115, the reflectance in the effective viewing angle range can be improved.

As such, the structure having the unevenness of the reflective electrode 119a may be applied to the structure in which the storage upper electrode and the drain electrode are connected.

The first passivation layer 116a may be formed under the transmissive electrode 115 and the interlayer insulating layer 120. In this case, the uneven pattern 116b is formed on the interlayer insulating layer 120.

For reference, although not shown in the drawing, a bonding bump is formed therein to apply a signal to the gate pad terminal 115a and the source pad terminal 115b. COG bonding bumps are formed in the two contact holes 118a and 118b.

In the case of the COF and TAP methods, the bonding bumps may be large so that the bonding bumps may not enter the first and second contact holes. In this case, conductive balls are formed in the first and second contact holes, and the upper part of the conductive balls is bonded. Since bumps are formed, the bonding pads are connected to the gate pad terminals 115a and the source pad terminals 115b through the first and second contact holes, so that no separate bonding problem occurs.

Next, a method of manufacturing a reflective transmissive liquid crystal display device having the above configuration will be described with reference to FIGS. 9A to 9C and 10A to 10C.

First, as shown in FIGS. 9A and 10A, aluminum (Al), molybdenum (Mo), tungsten (W), and other conductive alloys, which are conductive metals, are deposited and patterned on the transparent substrate 110, and then predetermined at the ends. A gate pad 111a having an area and having a first hole, a gate line 111 extending in one direction from the gate pad 111a, and a gate electrode 111b protruding a predetermined area from the gate line 111. To form.

At the same time as the gate line 111 is formed, the storage lower electrode 111c is formed in the storage capacitor region of the front gate line.

Next, an insulating material such as a silicon oxide film (SiO 2) or a silicon nitride film (SiN x) is deposited on the entire surface of the substrate 110 on which the gate line 111 is formed, and amorphous silicon (a-Si) and amorphous silicon containing impurities are successively deposited. To form a first insulating layer and a semiconductor layer (amorphous silicon + impurity amorphous silicon).

Thereafter, the semiconductor layer is patterned to form a semiconductor pattern in an island shape on the gate electrode 111b.

A conductive metal such as molybdenum (Mo), tungsten (W), or chromium (Cr) is deposited and patterned on the entire surface of the substrate 110 on which the semiconductor pattern is formed.

The patterning process may be performed to form a data line 114 so as to intersect with the gate line 111 with the first insulating layer therebetween, and a source pad having a second hole at one end of the data line 114. 114a is formed, and a source electrode 114b is formed to protrude from one side of the data line 114 to overlap one side of the semiconductor pattern.

At the same time as the data line 114 is formed, a drain electrode 114c is formed to be spaced apart from the source electrode 114b by a predetermined interval and overlap the other side of the semiconductor pattern, and is spaced apart from the drain electrode 114c. The storage upper electrode 114d is formed on the storage lower electrode 111c of the gate line.

Thereafter, an amorphous silicon layer doped with the source electrode 114b and the drain electrode 114c as a mask is etched to form an active layer 113 formed of an amorphous silicon layer in the semiconductor pattern, and an active layer except for a channel region. An ohmic contact layer 113a formed of a doped amorphous silicon layer is formed on 113.

Next, as shown in FIGS. 9B and 10B, indium tin oxide (ITO) and indium zinc are formed on the entire surface of the substrate 110 on which the source electrode 114b and the drain electrode 114c are formed. Depositing and wet etching one selected from a group of transparent conductive metals including indium zinc oxide (IZO) to directly contact the storage upper electrode 114d formed on the drain electrode 114c and the front gate line. The transmissive electrode 115 is formed in the pixel region.

In this case, the transmissive electrode 115 may be formed to be larger than a region in which a second through hole (see FIGS. 9C and 10C) will be formed later.

Next, an interlayer insulating film 120 made of a silicon nitride film is deposited on the entire surface of the substrate 110 including the transmissive electrode 115, and then transmissive in one region and the pixel region of the gate pad terminal 115a and the source pad terminal 115b. The interlayer insulating film 120 is patterned to expose one region of the electrode 115.

The interlayer insulating layer 120 is formed to surround side surfaces of the gate pad 111a and the source pad 114a. In this case, the interlayer insulating layer 120 is formed to extend at least 3 μm from the side surfaces of the gate pad 111 a and the source pad 114 a.

Subsequently, as illustrated in FIGS. 9C and 10C, one selected from the group of organic insulating materials including benzocyclobuten (BCB), photoacryl resin, and the like may be coated to form a first protective film ( 116a).

Subsequently, an organic material such as photo acryl is applied onto the first passivation layer 116a, and then the organic material is patterned by using an embossing technique to a portion corresponding to the reflector. The uneven pattern 116b is formed.

Next, a photo process is performed to pattern the first passivation layer 116a and the concave-convex pattern 116b to form a first through hole so that the transmissive electrode 115 of the pixel region is exposed, and at the same time, the gate pad terminal 115a. And the first and second contact holes 118a and 118b are formed on the source pad terminal 115b by performing a pad opening process.

Thereafter, a reflective metal having a low resistance value, such as aluminum (Al), an aluminum alloy, or Ag, and excellent reflectance is deposited on the entire surface of the substrate 110 including the uneven pattern 116b, and then patterned to form the transmissive electrode 115. The reflective electrode 119a is formed in the reflecting portion of the pixel region so as to contact the transmissive electrode 115 at the inclined step and the lower surface of the first through hole. A second through hole 117 through which the transmission electrode 115 is exposed is formed.

In this case, the reflective electrode 119a is formed by stacking a first metal having a lower resistance than a single layer structure and a second metal having good reflectivity, wherein the first metal uses Mo, and the second metal uses Al or AlNd.

The reason for forming as described above is that when Mo and the transparent electrode (ITO) are contacted, contact resistance can be lowered than when Al or AlNd is contacted with the transparent electrode. Galvanic corrosion problems occur to prevent this.

When removing the reflective metal, all of the reflective metal on the gate pad 111a and the source pad 114a are also removed.

In this case, the gate pad 111a and the source pad 114a are separated from each other with the first and second holes therein, and the interlayer insulating layer 120 is formed on the upper side thereof to etch the reflective metal. The etchant is prevented from penetrating through the pin holes of the gate pad terminal 115a and the source pad terminal 115b formed of the transparent conductive metal, thereby preventing damage to the gate pad 111a and the source pad 114a. can do.

In this case, the reflective electrode 119a is formed to overlap the data line 114 defining the pixel area by a predetermined interval.

The first passivation layer 116a may be formed under the transmissive electrode 115 and the interlayer insulating layer 120. In this case, the uneven pattern 116b is formed on the interlayer insulating layer 120.

For reference, although not shown in the drawing, a bonding bump is formed therein to apply a signal to the gate pad terminal 115a and the source pad terminal 115b. COG bonding bumps are formed in the two contact holes 118a and 118b.

In the case of the COF and TAP methods, the bonding bumps may be large so that the bonding bumps may not enter the first and second contact holes. In this case, conductive balls are formed in the first and second contact holes, and the upper part of the conductive balls is bonded. Since bumps are formed, the bonding pads are connected to the gate pad terminals 115a and the source pad terminals 115b through the first and second contact holes, so that no separate bonding problem occurs.

Although the invention has been described as a preferred embodiment, those skilled in the art will recognize that many modifications can be made without departing from the scope of the invention as defined in the appended claims.

The reflection-transmissive liquid crystal display device and a method of manufacturing the same of the present invention as described above have the following effects.

First, since the gate pad and the source pad are formed by isolating the first and second holes therein, and the interlayer insulating film is formed to cover the side surfaces of the gate pad and the source pad in the first and second holes, the reflective electrode is subsequently formed. It is possible to improve process reliability by preventing damage during etching.

Second, by forming the reflective electrode in a two-layer structure such as Mo-Al or Mo-AlNd, it is possible to prevent the galvanic problem from occurring at the interface with the transmission electrode.

Third, it is possible to improve the reflection efficiency compared to the conventional by forming the reflective electrode above the transmissive electrode.

Fourth, since a process of depositing a separate silicon nitride film after forming the uneven pattern composed of photo acryl is not required, a problem of deterioration of the photo acryl due to temperature can be prevented.

1 is an exploded perspective view showing a part of a general reflective transmissive liquid crystal display device

2 is a cross-sectional view of a typical reflective transmissive liquid crystal display device

3 and 4 are a plan view and a structural cross-sectional view of a conventional transflective liquid crystal display device.

5A to 5C are gradual plan views showing enlarged pixels of an array substrate of a conventional method of manufacturing a reflective transmissive liquid crystal display device;

6A through 6C are cross-sectional views of the process sequence of FIG. 5A through FIG. 5C, taken along the lines I-I ', II-II', III-III 'and IV-IV'.

7 and 8 are a plan view and a structural sectional view of a reflective transmissive liquid crystal display device according to an embodiment of the present invention.

9A to 9C are sectional plan views showing enlarged pixels of an array substrate of a method of manufacturing a reflective transmissive liquid crystal display device according to an exemplary embodiment of the present invention.

10A to 10C are cross-sectional views of the process sequence of FIG. 9A to FIG. 9C taken along the line V-V ′, VI-VI ′, VIII-VIII and VIII-VIII.

Explanation of symbols on the main parts of the drawings

110 substrate 111 gate line

111a: gate pad 111b: gate electrode

111c: storage lower electrode 112: gate insulating film

113: active layer 113a: semiconductor layer

113a: ohmic contact layer 114: data line

114a: source pad 114b: source electrode

114c: drain electrode 114d: storage upper electrode

115: transmission electrode 115a: gate pad terminal

115b: source pad terminal 116a: first protective film

116b: uneven pattern 117: second through hole

118a: first contact hole 188b: second contact hole

119a: reflective electrode 120: interlayer insulating film

Claims (28)

In the liquid crystal display device in which each pixel area is defined as a reflection area and a transmission area, A plurality of gate lines and data lines intersecting to define a pixel area; A thin film transistor formed at an intersection of the gate line and the data line; A gate pad and a source pad having first and second holes at one end of the gate line and the data line, the inner side of the gate line and the source line being separated from each other; A transmission electrode connected to the drain electrode of the thin film transistor and formed in the pixel region; A gate pad terminal and a source pad terminal in contact with the gate pad and the source pad through the first and second holes; An interlayer insulating film formed on the substrate including the transmissive electrode to surround side surfaces of the gate pad and the source pad; An uneven pattern formed on the reflective region; And a reflective electrode formed on the reflective region including the uneven pattern so that a part of the transparent electrode is exposed. The method of claim 1, And a passivation layer is further disposed on the interlayer insulating layer including the transmissive electrode. The method of claim 2, And the passivation layer is formed under the transmissive electrode and the interlayer insulating layer. The method of claim 1, The transmission electrode, the gate pad terminal, and the source pad terminal may be formed of indium tin oxide (ITO), tin oxide (TO), indium zinc oxide (IZO), or indium tin zinc oxide ( Reflective liquid crystal display device, characterized in that formed of a transparent conductive metal such as Indium Tin Zinc Oxide (ITZO). The method of claim 1, And said interlayer insulating film is formed of a silicon nitride film. The method of claim 1, And said interlayer insulating film extends about 3 [mu] m from the sides of the gate pad and the source pad. The method of claim 1, And an insulating film having a contact hole on the drain electrode of the thin film transistor under the transmissive electrode, wherein the transmissive electrode is in contact with the drain electrode through the contact hole. Device. The method of claim 1, And the reflective electrode overlaps with the data line defining the pixel area. The method of claim 1, The reflective electrode is a transflective liquid crystal display device, characterized in that the two-layer structure of Mo-Al or Mo-AlNd. The method of claim 1, And a storage upper electrode formed integrally with the front gate line and a storage upper electrode interposed between the gate insulating layer on the storage lower electrode. The method of claim 1, And the transmissive electrode is in direct contact with the storage upper electrode and the drain electrode of the thin film transistor. The method of claim 1, And a drain electrode of the thin film transistor is extended to the pixel region and connected to the upper electrode of the storage. The method of claim 1, A semiconductor layer occupying a predetermined area is further formed below the source pad, and the second hole is formed so that one region of the semiconductor layer is exposed. The method of claim 1, And a bonding bump formed to be in contact with the gate pad terminal and the source pad terminal. In the liquid crystal display device in which each pixel area is defined as a reflection area and a transmission area, A plurality of gate lines and data lines intersecting to define a pixel area; A thin film transistor formed at an intersection of the gate line and the data line; A storage upper electrode of the storage capacitor formed integrally with the drain electrode of the thin film transistor and formed on a front gate line; A gate pad and a source pad having first and second holes at one end of the gate line and the data line, the inner side of the gate line and the source line being separated from each other; A transmission electrode connected to the drain electrode of the thin film transistor and formed in the pixel region; A gate pad terminal and a source pad terminal in contact with the gate pad and the source pad through the first and second holes; An interlayer insulating film formed on the substrate including the transmissive electrode to surround side surfaces of the gate pad and the source pad; A passivation layer provided with a first through hole having an inclined step so that a part of the transmissive electrode is exposed; An uneven pattern formed on the reflective region including the storage upper electrode and the drain electrode; And an inclined stepped portion including the uneven pattern, the protective film upper portion, and a reflective electrode formed in the reflective region below the first through hole adjacent to the inclined step so that the transmissive electrode is exposed with a second through hole. Reflective type liquid crystal display device characterized in that. The method of claim 15, And the reflective electrode is in contact with the transmissive electrode at a lower surface of the first transmissive hole extending at an inclined step. In the manufacturing method of the liquid crystal display device wherein each pixel area is defined as a reflection area and a transmission area, Forming a plurality of gate lines arranged in one line direction and protruding from one side to constitute a gate electrode; Forming a gate pad having a first hole at one end of the gate line to isolate an interior of the gate line; Forming a plurality of data lines intersecting the gate line to define a pixel region, a source electrode protruding from the data line, and a drain electrode spaced apart from the source electrode; Forming a source pad having a second hole at one end of the data line to isolate the inside of the source line; Forming a transmissive electrode in the pixel region in contact with the drain electrode; Forming a gate pad terminal and a source pad terminal to contact the gate pad and the source pad through the first and second holes; Forming an interlayer insulating film on the substrate including the transmissive electrode to surround side surfaces of the gate pad and the source pad; Forming a protective film having a transmission hole so that a part of the transmission electrode is exposed; Forming an uneven pattern on the passivation layer of the reflective region; And forming a reflective electrode in the reflective region including the uneven pattern so as to be in contact with the transmissive electrode. The method of claim 17, And said interlayer insulating film is formed of a silicon nitride film. The method of claim 17, And the interlayer insulating layer is formed to extend approximately 3 μm from side surfaces of the gate pad and the source pad. The method of claim 17, The protective film having the transmissive hole is formed before the transmissive electrode is formed. The method of claim 17, The protective film is formed of one selected from the group of organic insulating materials containing benzocyclobuten (BCB), photoacryl resin (resin) and the like. The method of claim 17, And forming first and second contact holes in the gate pad terminal and the source pad terminal when forming the transmission hole. The method of claim 17, And the uneven pattern is formed by applying an embossing technique after applying an organic material such as photo acryl on the passivation layer. The method of claim 17, And the reflective electrode is formed to be in contact with the transmissive electrode at an edge of the transmissive hole. The method of claim 17, And the reflective electrode is formed by stacking a first metal having a low resistance and a second metal having good reflectivity. The method of claim 17, The first metal is Mo, and the second metal is Al or AlNd manufacturing method of a reflective liquid crystal display device. The method of claim 17, And the transmissive electrode is formed to be in direct contact with both the drain electrode and the upper storage electrode. The method of claim 22, And forming a bonding bump in the first and second contact holes to contact the gate pad terminal and the source pad terminal.