KR20070065065A - Method for manufacturing transflective type liquid crystal display device - Google Patents

Abstract

A method for manufacturing a transflective LCD(Liquid Crystal Display) is provided to reduce the number of processes and a manufacturing cost of an LCD panel by simultaneously forming a column spacer and a pattern for cell-gap adjustment of a reflective area through one masking process. A black matrix(110) is patterned on a substrate. Color filters(120) including red, green and blue are patterned in regions between portions of the black matrix, and a stack pattern is formed by stacking the color filters at one side of the substrate. An upper cell-gap adjustment pattern(130) is formed on the color filter, and a spacer is formed on the stack pattern. The step of forming the cell-gap adjustment pattern on the color filter and the spacer on the stack pattern includes applying an over-coat layer on the substrate including the color filter and the stack pattern, providing a mask on the overcoat layer, exposing an upper region of the stack pattern and a region excluding the upper cell-gap adjustment pattern through an exposure process, and removing the exposed region through a development process.

Description

Manufacturing method of transflective liquid crystal display device {METHOD FOR MANUFACTURING TRANSFLECTIVE TYPE LIQUID CRYSTAL DISPLAY DEVICE}

1 is a cross-sectional view for explaining a conventional transflective liquid crystal display device.

2A to 2C are cross-sectional views illustrating a method for manufacturing a color filter substrate of a conventional transflective liquid crystal display device.

3 is a plan view of a liquid crystal display according to an exemplary embodiment of the present invention.

4 is a cross-sectional view taken along line A-A of the liquid crystal display of FIG. 3.

5 is a cross-sectional view for explaining a modification of the present embodiment.

6 and 7 are cross-sectional views illustrating a method of manufacturing a color filter substrate according to an embodiment of the present invention.

8A and 8B are cross-sectional views illustrating a method of forming a column spacer and an upper cell gap adjustment pattern according to the present embodiment.

<Explanation of symbols for the main parts of the drawings>

10, 110: black matrix 20, 120: color filter

30, 70, 130, 240: cell gap adjustment pattern 40, 140: common electrode

50, 240: reflective electrode 60, 250: pixel electrode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a transflective liquid crystal display, and more particularly, to a method of manufacturing a transflective liquid crystal display capable of simplifying a manufacturing process by simultaneously manufacturing a step pattern and a column spacer for forming a multi-cell gap.

In today's information society, the role of electronic display devices becomes more and more important, and various electronic display devices are widely used in various industrial fields.

In general, an electronic display device refers to a device that transmits various information to a human through vision. In other words, an electronic display device may be defined as an electronic device that converts electrical information signals output from various electronic devices into optical information signals that can be recognized by human eyes, and serves as a bridge that connects humans and electronic devices. It may be defined as.

In such an electronic display device, when an optical information signal is displayed by a light emitting phenomenon, it is called an emissive display device, and when a light modulation is displayed by reflection, scattering, or interference phenomenon, a light receiving display ( It is called a non-emissive display device. The light emitting display device, also called an active display device, includes a cathode ray tube (CRT), a plasma display panel (PDP), a light emitting diode (LED), and an electroluminescent display (electroluminescence display). luminescent display; ELD). In addition, the light receiving display device, which is a passive display device, includes a liquid crystal display (LCD), an electrochemical display (ECD), and an electro phoretic image display (EPID). .

Cathode ray tubes (CRTs) used in image display devices such as televisions and computer monitors occupy the highest share in terms of display quality and economy, but have many disadvantages such as heavy weight, large volume and high power consumption. .

However, due to the rapid progress of semiconductor technology, the electronic display device suitable for the new environment, that is, the thin and light, the low driving voltage and the low power consumption, according to the solidification, low voltage and low power of various electronic devices, and the small size and light weight of electronic devices The demand for flat panel display devices with features is rapidly increasing.

Among the various flat panel display devices currently developed, liquid crystal displays are thinner and lighter than other display devices, have low power consumption and low driving voltage, and are widely used in various electronic devices because they are capable of displaying images close to cathode ray tubes. Is being used.

Such a liquid crystal display may be broadly classified into a transmissive liquid crystal display displaying an image using an internal light source such as a backlight and a reflective liquid crystal display using external incident light such as natural light.

The transmissive liquid crystal display device has a high brightness of the screen because a back light unit is installed on the back and used as its own light source, but it is difficult to apply to a portable device because of high power consumption.

On the other hand, the reflective liquid crystal display displays an image by selectively transmitting natural light incident from the outside by the switching action of the liquid crystal layer and reflecting it back from the reflecting plate to be emitted to the front surface. It has a disadvantage that it is difficult to use in a low brightness and dark place because there is no own light source.

The semi-transmissive liquid crystal display device for solving the shortcomings of the transmissive and reflective liquid crystal display device displays an image by using both the external incident light and the light of the backlight unit.

1 is a cross-sectional view for describing a conventional transflective liquid crystal display device.

As shown in FIG. 1, a general transflective liquid crystal display device includes a thin film transistor substrate 2 and a color filter substrate 1 in which reflective and transmissive regions are defined, and is provided to maintain a cell gap between the two substrates. And a spacer 80 and a liquid crystal layer injected between the two substrates.

The color filter substrate 1 includes a black matrix 10, a color filter 20, and a common electrode 40. The thin film transistor substrate 2 includes a gate line (not shown), a source line 3, and a thin film transistor pattern (not shown) provided therebetween, and the thin film transistor substrate corresponding to the reflective and transmissive regions is formed. (2) is provided with the reflection electrode 30 and the transparent electrode 40, respectively.

In the transflective liquid crystal display, the reflective electrode 50 reflects the light incident from the outside (color filter substrate) in the reflective mode and emits the light to the upper plate. It exits to the upper plate through the transparent pixel electrode 60 located in the region.

In this case, when the cell gap between the thin film transistor substrate 2 and the color filter substrate 1 is constant, the path through which the light passes through the liquid crystal layer is different in the transmission region and the reflection region. That is, in the transmissive region, light from the backlight passes through the liquid crystal layer only once, while in the reflective region, the light incident from the color filter substrate 1 passes through the liquid crystal layer and then reflects back from the reflective electrode 50. It passes through the liquid crystal layer and is emitted as reflected light. For this reason, the distance through which the reflected light passes through the liquid crystal layer is longer than that of the transmitted light. Therefore, in order to obtain optimal optical characteristics in both the reflection mode and the transmission mode, it is necessary to design different cell gaps between the reflection area and the transmission area.

Accordingly, as shown in FIG. 1, the lower cell gap adjustment pattern 70 is formed on the thin film transistor substrate 2 corresponding to the reflective region, and the upper cell gap adjustment pattern 30 is formed on the color filter substrate 1. Formed. As a result, the cell gap d of the reflective region is narrower than the cell gap 2d of the transmissive region, thereby adjusting the distance that light passes through the liquid crystal layer. The transflective liquid crystal display of such a configuration is generally called a multi-cell gap transflective liquid crystal display.

In the related art, a column spacer 80 is provided between the thin film transistor substrate 2 and the color filter substrate 1 in order to maintain a constant gap between the multi-cell gaps as described above.

In general, these column spacers 80 are formed on the upper cell gap adjustment pattern of the color filter substrate 1 to keep the inter-cell gap constant. The column spacer 80 was formed by applying a predetermined resin onto the upper cell gap adjustment pattern 30 and then patterning the resin.

Hereinafter, a method of manufacturing a color filter substrate including a conventional column spacer will be described with reference to the drawings.

2A to 2C are cross-sectional views illustrating a method of manufacturing a color filter substrate of a conventional transflective liquid crystal display device.

Referring to FIG. 2A, the black matrix 10 is formed by coating and patterning a black matrix film on the substrate 1, and the color filter 20 is formed by coating and patterning the film for color filter.

Referring to FIG. 2B, an overcoat film is coated on a substrate 1 on which lower patterns such as the black matrix 10 and the color filter 20 are formed, followed by exposure using a mask, and development to adjust upper cell gaps. The pattern 30 is formed. In this case, the upper cell gap adjustment pattern 30 includes a shape in which the overcoat layer remains in the reflective region and protrudes, and the overcoat layer in the transmissive region is removed to concave. Thereafter, a transparent common electrode 40 is formed on the upper cell gap adjustment pattern 30 along the step.

Referring to FIG. 2C, a column spacer 80 is formed on the upper cell gap adjustment pattern 30 by applying an organic film for a spacer on the entire structure shown in FIG. 2B and then performing exposure and development using a mask.

As described above, in order to form the upper cell gap adjustment pattern and the column spacer on the substrate on which the lower pattern is formed, two photo development processes using two masks must be performed. That is, one photo development process for forming the upper cell gap adjustment pattern and another photo development process for forming the column spacers must be performed. As a result, the manufacturing process of the liquid crystal display device becomes complicated and the production cost of the liquid crystal display device increases.

Accordingly, the present invention was derived to solve the above problems, and provides a method of manufacturing a transflective liquid crystal display device which can reduce the number of manufacturing processes by simultaneously forming a pattern for adjusting the cell gap of a reflective region and a column spacer. It is for that purpose.

Patterning a black matrix on a substrate according to the present invention, patterning a color filter including red, blue, and green in a region between the black matrices, and forming a stacked pattern in which the color filters are stacked on one side of the substrate And forming an upper cell gap adjustment pattern on the color filter and simultaneously forming a spacer on the stack pattern.

The forming of the upper cell gap adjustment pattern on the color filter and simultaneously forming the spacer on the stack pattern may include applying an overcoat layer on the substrate on which the color filter and the stack pattern are formed. And providing a mask on the overcoat layer, exposing an upper region of the stack pattern and an area other than the upper cell gap adjustment pattern region through an exposure process, and exposing the exposed region through a development process. It is preferred to include the step of removing.

And after the said image development process, you may perform a baking process further.

Patterning the color filter including red, blue, and green in the area between the black matrices, and forming the stacked pattern in which the color filters are stacked on one side of the substrate may include a red color filter on the substrate. Patterning and forming a first stacked pattern including the red color filter, patterning a green color filter on the substrate, and forming a second stacked pattern including the green color filter; Patterning a blue color filter on the substrate, and forming a third stacked pattern comprising the blue color filter.

Of course, patterning the color filter including red, blue, and green in the region between the black matrix, and forming a common electrode after forming the stacked pattern in which the color filter is stacked on one side of the substrate, It may further include.

Also, a light blocking area and a pixel area according to the present invention are defined, and the pixel area includes a color filter substrate and a thin film transistor substrate defined as a transmission area and a reflection area, and on the light blocking area of the color filter substrate. Forming a black matrix, patterning a color filter including red, blue, and green in the pixel area, and forming a stacked pattern in which the color filters are stacked in a part of the light blocking area, and forming a spacer on the stacked pattern And simultaneously forming an upper cell gap adjustment pattern on the reflective region, forming a lower pattern including a thin film transistor in the light blocking region of the thin film transistor substrate, and forming the lower pattern corresponding to the reflective region. Forming a reflective electrode on the pixel and forming a pixel electrode on the pixel region; Pressurizing and sealing the color filter substrate on which the cell gap adjustment pattern is formed, the thin film transistor substrate on which the lower pattern, the reflective electrode, and the pixel electrode are formed, and injecting liquid crystal between the sealed substrate. Provided is a method of manufacturing a transflective liquid crystal display device.

The method may further include forming a lower cell gap adjustment pattern on the reflective region after the forming of the lower pattern including the thin film transistor in the light blocking region of the thin film transistor substrate.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and the scope of the invention to those skilled in the art. It is provided for complete information.

In the drawings, the thickness of layers, films, panels, regions, etc., may be exaggerated for clarity, and like reference numerals designate like elements. In addition, when a part such as a layer, a film, an area, or a plate is expressed as being on or above another part, not only when each part is directly above or directly above the other part but also another part between each part and another part This includes cases.

3 is a plan view of a liquid crystal display according to an exemplary embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line A-A of the liquid crystal display of FIG. 3. 5 is a cross-sectional view for explaining a modification of the present embodiment.

3 to 5, the liquid crystal display according to the present exemplary embodiment includes a color filter substrate 1000 and a thin film transistor substrate 2000 in which light blocking regions, transmission regions, and reflection regions are defined, and between the two substrates. It includes a liquid crystal layer provided in. The liquid crystal display device is defined as a light blocking area in which a circuit pattern such as a switching element is formed, and a pixel area displaying an image, wherein the pixel area transmits light of a lower backlight to display an image, and reflects natural light to reflect an image. It is separated into a reflective area to display.

In the color filter substrate 1000, the black matrix 110 and the column spacer 150 are formed in the light blocking area, the color filter 120 is patterned in the pixel area, and the upper cell gap adjustment pattern 130 is formed in the reflective area. And a common electrode 140 formed along the steps of the patterns. An upper cell gap adjustment pattern may also be formed in part of the light blocking region. The common electrode 140 may be formed under the upper cell gap adjustment pattern 130 as shown in FIG. 5. That is, it may be formed on the black matrix 110 and the color filter 120.

The thin film transistor substrate 2000 includes a thin film including a gate electrode 211, a gate insulating film 212, an active layer 213, an ohmic contact layer 214, a source electrode 215, and a drain electrode 216 formed in a light blocking region. A lower cell gap adjustment pattern 230 formed on the reflective region and at least a portion of the lower cell gap adjustment pattern 230 including a transistor, a gate line 210 and a source line 220 connected thereto. The reflective electrode 240 is formed, and the pixel electrode 250 is formed on the pixel region. Of course, the present invention does not form the upper lower cell gap adjustment pattern 230 as shown in FIG. 5, but forms only the protective layer 232 for protecting the lower patterns, and the reflective electrode 240 and the pixel electrode thereon. 250 may be formed. In this case, the path of the light passing through the liquid crystal layer in the transmissive region and the reflective region may be the same through the upper cell gap adjustment pattern 130 provided in the color filter substrate 1000. The reflective electrode 240 may have a wave pattern formed thereon. As shown in the drawing, a predetermined insulating film 242 is formed between the reflective electrode 240 and the pixel electrode 250. Of course, the pixel electrode 250 may be directly formed on the reflective electrode 240 or the reflective electrode 240 may be formed on the pixel electrode 250 without forming the insulating layer 242.

Here, the column spacer 150 formed on the color filter substrate 1000 is formed at the same time as the upper cell gap adjustment pattern 130, and includes a plurality of color filter films for height adjustment of the column spacer 150. It is preferable to consist of a thin film. That is, as shown in FIGS. 4 and 5, color filter films 120 corresponding to R, G, and B are sequentially stacked, and thin films for forming the upper cell gap adjustment pattern 130 are stacked thereon. Can be formed. The column spacer 150 may be disposed on upper portions of the thin film transistor or gate line 210 and the source line 220 formed in the light blocking region of the thin film transistor substrate 2000.

A color filter substrate 100 having a column spacer 150 formed on a thin film transistor substrate 2000 coated with a sealant such as a sealant and coated with a sealant is formed along an edge of the thin film transistor substrate 2000. Arrange and then press seal. At this time, the gap between the two substrates is kept constant by the column spacer 150. In this case, it is preferable that the gap between the two substrates is larger than the cell gap of the transflective area by the upper cell gap adjustment pattern 130 and the lower cell gap adjustment pattern 230. And it is preferable that an oriented film is formed in the surface of the said opposing board | substrate. Thereafter, a liquid crystal is injected into the sealed cell gap to complete a liquid crystal display.

As described above, the present invention can simplify the manufacturing process of the color filter substrate by simultaneously forming the upper cell gap adjustment pattern and the column spacer. Hereinafter, a method of manufacturing the color filter substrate according to the present embodiment will be described with reference to the drawings.

6 and 7 are cross-sectional views illustrating a method of manufacturing a color filter substrate according to an exemplary embodiment of the present invention. 8A and 8B are cross-sectional views illustrating a method of forming a column spacer and an upper cell gap adjustment pattern according to the present embodiment.

Referring to FIG. 6, the black matrix 110 and the color filter 120 are patterned on the transparent substrate 100, and the stack patterns 120a, 120b, and 120c for column spacers are formed on one side of the transparent substrate 100. Form.

The patterning of the black matrix 110 and the color filter 120 proceeds as follows. First, the organic film for black matrices is apply | coated on the translucent insulation board | substrate 100. FIG. At this time, it is preferable that the organic film for black matrices use the chromium / chromium oxide double layer which has light shielding property, or the organic film which consists of carbon black, titanium oxide, etc. The organic film for a black matrix is patterned by performing a photo developing process using a mask for patterning the black matrix 110.

On the patterned black matrix 110, a color filter 120 of red color (R), green color (G), and blue color (B) is sequentially formed, and a stack for spacers including the color filter 120 is formed. Patterns 120a, 120b, and 120c are formed. To this end, a photoresist film including an azo red pigment is coated on the substrate 100 on which the black matrix 110 is formed, and the photoresist film is exposed to a predetermined pattern using a mask. Thereafter, the photosensitive film is developed according to the exposed pattern, and the developed photosensitive film is cured to form a red color filter, and together with the first stacked pattern 120a for the spacer. Subsequently, a photoresist film containing a protarocyanine-based green pigment is applied onto the substrate 100 on which the red color filter is formed, and the photoresist film is exposed to a predetermined pattern using a mask. Thereafter, the photoresist film is developed according to the exposed pattern, the developed photoresist film is cured to form a green color filter, and together with the second stacked pattern 120b for spacers. Subsequently, a photoresist film containing a phthalocyanine-based blue pigment is applied onto the substrate 100, exposed and developed using a mask, and then the photoresist film is cured to form a blue color filter, together with a third stack for spacers. It is preferable to form the pattern 120c.

The patterns of the red, green, and blue color filters 120 may be formed to be spaced apart from each other by the same size as shown in the drawing, and patterned to different thicknesses according to the characteristics of the color filters 120. You can do this, or you can pattern them so that they overlap each other.

In addition, the stacked layers of the column spacer stack patterns 120a, 120b, and 120c manufactured together with the color filter 120 may be changed according to the height of the column spacer 150. That is, in the drawings, the stacking patterns 120a, 120b and 120c for the column spacer having three layers have been described. However, the present invention is not limited thereto, and one or two layers are stacked to stack the stacking patterns 120a, 120b and 120c. It may be formed.

Referring to FIG. 7, the upper cell gap adjustment pattern 130 is formed on the patterned black matrix 110 and the color filter 120, and on the stacked patterns 120a, 120b, and 120c for the column spacer. The column spacer 150 is formed, and a common electrode 140 is formed on the column spacer 150. It is preferable that the upper cell gap adjustment pattern 130 is formed on the reflection area so that the reflection area becomes a protruding shape and the transmission area is concave.

As the common electrode 140 layer, indium tin oxide (ITO) or indium zinc oxide (IZO) is preferably used.

Here, the upper cell gap adjustment pattern 130 and the column spacer 150 may be patterned at the same time. That is, the overcoat layer 131 may be coated on the entire structure and exposed and developed using a mask to manufacture the sal gap adjustment pattern 130 and the column spacer 150 at once. This can reduce the photo development process using the mask, it is possible to reduce the manufacturing cost.

To this end, as shown in FIG. 8A, an overcoat layer 131 is coated on the black matrix 110, the color filter 120, and the stacked patterns 120a, 120b and 120c for the column spacer. As the overcoat layer 131, a material whose property is changed by light or heat is used, but a photoresist-based material that is cured by light is preferably used. In this embodiment, it is preferable to use photosensitive transparent resin.

The overcoat layer 131 is exposed to light using a mask and then developed to form the column spacer 150, and the upper cell gap adjustment pattern 130 protruding from the reflective region is formed.

Here, the mask 300 is provided with a column spacer region and a light shielding portion 301 through which light cannot pass through the reflective region, and a transmission portion 302 through which light passes through the remaining region. When exposure is performed using such a mask, the overcoat film 131 under the transmissive part is exposed to change its chemical property, and the overcoat film 131 under the light shielding part does not change its chemical property. As such, when the chemical property of the overcoat layer 131 is changed through the exposure process and then the development process is performed, only the overcoat layer 131 in the region where the chemical property is changed is removed. Thereafter, the overcoat layer 131 remaining through the baking process is cured to form the upper cell gap adjustment pattern 130 and the column spacer 150 as shown in FIG. 8D.

In the above description, the overcoat film 131 in which the region irradiated with light is removed in a subsequent development process has been described. However, the present invention is not limited thereto, and the overcoat layer 131 in which the region irradiated with light remains may be used. have. That is, both positive and negative photosensitive materials may be used.

As described above, the present invention may form the column spacer 150 and the upper cell gap adjustment pattern 130 through one photo development process. In this case, the distance of the light passing through the liquid crystal layer in the reflective region may be adjusted by adjusting the height of the upper cell gap adjustment pattern 130, and the stacked patterns 120a, 120b, and 120c at the bottom of the column spacer 150. ), The overall height of the column spacer 150 may be adjusted.

As described above, the column spacer and the pattern for adjusting the cell gap of the reflective region may be simultaneously formed through one masking process to reduce the number of processes and to reduce the production cost of the liquid crystal display panel by reducing the number of processes. .

Although the invention has been described with reference to the accompanying drawings and the preferred embodiments described above, the invention is not limited thereto, but is defined by the claims that follow. Accordingly, one of ordinary skill in the art may variously modify and modify the present invention without departing from the spirit of the following claims.

Claims (7)

Patterning the black matrix on the substrate; Patterning a color filter including red, blue, and green in a region between the black matrices, and forming a stacked pattern in which the color filters are stacked on one side of the substrate; Forming an upper cell gap adjustment pattern on the color filter and simultaneously forming a spacer on the stack pattern. The method of claim 1, wherein the forming of the upper cell gap adjustment pattern on the color filter and simultaneously forming the spacer on the stack pattern include: Applying an overcoat layer on the substrate on which the color filter and the lamination pattern are formed; Providing a mask on the overcoat layer; Exposing a region other than the upper portion of the stacked pattern and the upper cell gap adjustment pattern region through an exposure process; A method of manufacturing a transflective liquid crystal display device comprising removing the exposed region through a developing process. The method according to claim 2, The manufacturing method of the transflective liquid crystal display device which further performs a baking process after the said image development process. The method of claim 1, wherein the patterning of the color filters including red, blue, and green in the region between the black matrices and forming the stacked pattern in which the color filters are stacked on one side of the substrate comprises: Patterning a red color filter on the substrate, and forming a first stacked pattern including the red color filter; Patterning a green color filter on the substrate, and forming a second stacked pattern including the green color filter; And patterning a blue color filter on the substrate, and forming a third stacked pattern including the blue color filter. The method of claim 1, further comprising: patterning the color filters including red, blue, and green in the region between the black matrices, and forming the stacked pattern in which the color filters are stacked on one side of the substrate. A method of manufacturing a transflective liquid crystal display further comprising the step of forming a common electrode. Providing a color filter substrate and a thin film transistor substrate, wherein a light blocking region and a pixel region are defined, wherein the pixel region is defined as a transmission region and a reflection region; A black matrix is formed on the light blocking area of the color filter substrate, a color filter including red, blue, and green is patterned on the pixel area, and a stacked pattern in which the color filter is stacked is formed on a part of the light blocking area. Doing; Simultaneously forming a spacer on the stacked pattern and an upper cell gap adjustment pattern on the reflective region; Forming a lower pattern including a thin film transistor in the light blocking region of the thin film transistor substrate; Forming a reflective electrode on the lower pattern corresponding to the reflective region, and forming a pixel electrode in the pixel region; Pressing sealing the color filter substrate on which the spacer and the cell gap adjustment pattern are formed, and the thin film transistor substrate on which the lower pattern, the reflective electrode, and the pixel electrode are formed; And injecting a liquid crystal between the encapsulated substrates. The method of claim 6, after the forming of the lower pattern including the thin film transistor in the light blocking region of the thin film transistor substrate, A method of manufacturing a transflective liquid crystal display further comprising forming a lower cell gap adjustment pattern on the reflective region.

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