KR20080061107A - Liquid crystal display device and manufacturing method thereof - Google Patents

Abstract

An LCD(Liquid Crystal Display) and a manufacturing method thereof are provided to use the extinction light at a black matrix area in order to enhance the brightness of an LCD. The first array panel(130) includes a gate line formed on the first substrate. A data line is crossed with the gate line and defines a cell area. A pixel electrode is formed at the cell area. The second array panel includes a black matrix(164) formed on the second substrate located oppositely to the first substrate and for partitioning the cell area. A reflection pattern(154) is formed on the black matrix and a refraction pattern(156) has an embossing surface. Color filters(166) are formed on the cell areas. A back light unit(170) includes a light source for irradiating the light to the first and second array panels. A reflection plate(174) reflects the light beam irradiated from the light source toward the first and second array panels.

Description

Liquid crystal display device and manufacturing method thereof

1 is a cross-sectional view schematically showing a conventional liquid crystal display device.

FIG. 2 is a plan view illustrating a portion of a black matrix forming region and a thin film transistor array panel of the liquid crystal display shown in FIG. 1.

3 is a view showing a liquid crystal display device according to the present invention.

FIG. 4 is a diagram illustrating a portion of a black matrix forming region and a thin film transistor array panel of the liquid crystal display shown in FIG. 3.

FIG. 5 is an enlarged view of a region A1 shown in FIG. 3; FIG.

6 is a flowchart illustrating a method of manufacturing a liquid crystal display device according to the present invention.

7A to 7E are cross-sectional views for sequentially explaining a step of preparing a second array panel according to the present invention.

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

170: backlight unit 172: light source

174: reflector 176: optical sheet

130: first array panel 131: first substrate

106: thin film transistor 160: second array panel

162: second substrate 164: black matrix

154: reflection pattern 156: refraction pattern

166 color filter

190: path of light incident toward the black matrix

P1: transmission region P2: non-transmission region

The present invention relates to a liquid crystal display device and a manufacturing method thereof. In particular, the present invention relates to a liquid crystal display device and a method for manufacturing the same, which can use the light disappearing in the black matrix region to improve the brightness of the liquid crystal display device.

The liquid crystal display device displays an image by adjusting the light transmittance of the liquid crystal using an electric field. To this end, a conventional liquid crystal display device includes a liquid crystal display panel in which liquid crystal cells are arranged in a matrix form as shown in FIGS. 1 and 2, a driving circuit (not shown) for driving the liquid crystal panel, and light to the liquid crystal panel. The backlight unit 70 is provided for this purpose. The liquid crystal panel includes a thin film transistor array panel 30 and a color filter array panel 60 facing each other, a spacer (not shown) positioned between the two panels to maintain a constant cell gap, and a liquid crystal 80 filled in the cell gap. do.

The thin film transistor array panel 30 includes a gate line 2 and a data line 4 formed to intersect a gate insulating layer 33 therebetween on a lower substrate 31, and a thin film transistor 6 formed at each intersection thereof. And a pixel electrode 17 formed in the cell region provided in the intersection structure. The thin film transistor array panel 30 includes a storage capacitor 20 formed at an overlapping portion of the pixel electrode 17 and the previous gate line 2.

The thin film transistor 6 includes a gate electrode 8 connected to the gate line 2, a source electrode 10 connected to the data line 4, a drain electrode 12 connected to the pixel electrode 17, and A semiconductor pattern 18 is formed between the source electrode 10 and the drain electrode 12 and overlaps the gate electrode 8 with the gate insulating film 33 therebetween.

The semiconductor pattern 18 is formed to overlap the source electrode 10 and the drain electrode 12 to form a channel portion between the source electrode 10 and the drain electrode 12, the active layer 14, It consists of an ohmic contact layer 16 for ohmic contact between the source electrode 10 and between the active layer 14 and the drain electrode 12. The thin film transistor 6 serves as a switch for charging the pixel voltage signal supplied to the data line 4 to the pixel electrode 17 in response to the gate signal supplied to the gate line 2.

The pixel electrode 17 is connected to the drain electrode 12 of the thin film transistor 6 through a contact hole 15 penetrating through the passivation layer 35. The pixel electrode 17 generates a potential difference from the common electrode 52 provided in the color filter array panel 60 by the charged pixel voltage. By this potential difference, the liquid crystal 80 positioned between the thin film transistor array panel 30 and the color filter array panel 60 is rotated by dielectric anisotropy to adjust the light transmittance through the liquid crystal 80 to realize gray scale. .

The storage capacitor 20 includes a front gate line 2 and a pixel electrode 17 overlapping each other with the gate insulating layer 33 and the passivation layer 35 interposed therebetween. The storage capacitor 20 allows the pixel voltage charged in the pixel electrode 17 to be stably maintained until the next pixel voltage is charged.

The gate line 2 is supplied with the scan voltage from the gate driver, and the data line 4 transfers the data voltage supplied from the data driver to the pixel electrode 17 via the thin film transistor 6.

The color filter array panel 60 includes a black matrix 64, a color filter 66, a planarization layer 68, and a common electrode 52 sequentially formed on the upper substrate 62. The black matrix 64 is formed to overlap the thin film transistor region, the gate lines 2 and the data lines 4 of the thin film transistor array panel 30, and defines a cell region in which the color filter 66 is to be formed. do. The color filter 66 is formed in the cell region separated by the black matrix 64. The color filter 66 is formed for each of R, G, and B to implement R, G, and B colors. The planarization layer 68 is formed to planarize the upper substrate 62 surface on which the color filter 66 is formed. The common electrode 52 is formed to control the movement of the liquid crystal 80 by forming an electric field together with the pixel electrode 17 as described above.

The backlight unit 70 receives power from an external power source to irradiate light to the liquid crystal display panel. To this end, the backlight unit 70 includes one or more light sources 72 for irradiating light to the liquid crystal panel and a reflector 74 for reflecting light emitted from the light source 72 to the bottom of the backlight unit 70 toward the liquid crystal panel. Equipped.

The liquid crystal display panel of the liquid crystal display device is formed by patterning the color filter array panel 60 and the thin film transistor array panel 30 and then bonding them together. Therefore, the black matrix 64 of the color filter array panel 60 is formed with a wider width of the gate line 2 and the data line 4 in consideration of the bonding margin. Here, the light 90 incident on the region where the black matrix 64 is formed is hidden by the black matrix 64 and disappears without being displayed on the screen, and thus does not contribute to the luminance of the liquid crystal display. This problem occurs not only in the vertical field type liquid crystal display device illustrated in FIG. 1, but also in the horizontal field type liquid crystal display device in which the common electrode 52 is formed on the lower substrate 31 to form a horizontal electric field with the pixel electrode 17. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal display device and a method of manufacturing the same, which can use the light disappearing in the black matrix region to improve the brightness of the liquid crystal display device.

In order to achieve the above object, a liquid crystal display according to the present invention includes a gate line formed on a first substrate, a data line crossing the gate line to define the cell region, and a pixel electrode formed in the cell region. 1 array panel; And a black matrix formed on a second substrate facing the first substrate to define a cell region, a refractive pattern having a reflection pattern and an embossed surface formed on the black matrix, and color filters formed in the cell region. A second array panel; And a light source for irradiating light to the first and second array panels, and a reflector to reflect the light emitted from the light source toward the first and second array panels.

The black matrix pattern and the reflective pattern are formed in the same pattern.

The light incident from the light source to the reflective pattern is reflected toward the embossing surface of the refractive pattern, then is refracted at the surface of the refractive pattern to pass through the cell region, and then is incident on the reflector of the backlight unit to the color filter. Is investigated.

In addition, a method of manufacturing a liquid crystal display according to the present invention includes a first array including a gate line formed on a first substrate, a data line crossing the gate line to define the cell region, and a pixel electrode formed in the cell region. Providing a panel; Providing a second array panel including a black matrix formed on a second substrate to define a cell region, a refractive pattern having a reflective pattern and an embossed surface superimposed on the black matrix, and color filters formed in the cell region; Steps; Bonding the first and second array panels to face each other; And assembling a backlight unit including a light source for irradiating light to the first and second array panels, and a reflector to reflect light emitted from the light source toward the first and second array panels.

The preparing of the second array panel may include forming the black matrix and the reflective pattern on the second substrate; Forming the refractive pattern on the reflective pattern; And sequentially forming the color filter in the cell region.

The forming of the black matrix and the reflective pattern on the second substrate may include depositing an opaque material including an opaque metal or an opaque resin including chromium on the second substrate; Depositing a reflective metal comprising AlNd on the opaque material; Forming a photoresist pattern on the reflective metal; Etching the opaque material and the reflective metal using the photoresist pattern.

Other objects and advantages of the present invention other than the above object will be apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 3 to 7E.

The liquid crystal display according to the present invention forms a reflection pattern and a refraction pattern in the black matrix area of the second array panel, which is a color filter array panel, so that light incident on the black matrix area can be reflected to transmit the transmission area. Description of the liquid crystal display device according to the present invention will be specifically described as an example of the horizontal field type liquid crystal display device shown in FIGS.

3 is a diagram illustrating a liquid crystal display according to a first embodiment of the present invention. 4 is a diagram illustrating a portion of the black matrix forming region and the thin film transistor array panel of the liquid crystal display shown in FIG. 3. 5 is an enlarged view of an area A1 illustrated in FIG. 3.

3 to 5, the liquid crystal display according to the first embodiment of the present invention is a liquid crystal display panel (hereinafter, referred to as a liquid crystal panel) in which liquid crystal cells are arranged in a matrix form, for driving a liquid crystal panel. A driving circuit (not shown) and a backlight unit 170 for irradiating light to the liquid crystal panel are provided. The liquid crystal panel includes a first array panel 130 and a second array panel 160 facing each other, a spacer (not shown) positioned between the two panels to maintain a constant cell gap, and a liquid crystal 180 filled in the cell gap. . The liquid crystal panel overlaps with the black matrix 164, the gate line 102, the data line 104, and the thin film transistor 106 to form a non-transmissive region P2 through which no light is transmitted, and a transmissive region through which other light is transmitted. It is divided into (P1).

The backlight unit 170 receives power from an external power source to irradiate light to the liquid crystal display panel. To this end, the backlight unit 170 may include at least one light source 172 for irradiating light to the liquid crystal panel, a reflector 174 for reflecting light emitted from the light source 172 to the bottom of the backlight unit 170 toward the liquid crystal panel; The optical sheets 176 may be provided to improve the efficiency of light emitted from the light source 172 and irradiate the liquid crystal panel. In particular, the optical sheets 176 include a prism sheet so that light incident obliquely from the surface of the reflecting plate 174 passes toward the liquid crystal display panel vertically after passing through the prism sheet.

The first array panel 130 includes a gate line 102 and a data line 104 formed on the first substrate 131 with the gate insulating layer 133 interposed therebetween, and the thin film transistor 106 formed at each intersection thereof. And a pixel electrode 117 formed in the cell region provided in the intersection structure. The first array panel 130 includes a storage capacitor 120 formed at an overlapping portion of the pixel electrode 117 and the previous gate line 102.

The thin film transistor 106 includes a gate electrode 108 connected to the gate line 102, a source electrode 110 connected to the data line 104, and a drain electrode 112 connected to the pixel electrode 117. A semiconductor pattern 118 is formed between the source electrode 110 and the drain electrode 112 and overlaps the gate electrode 108 with the gate insulating layer 133 therebetween.

The semiconductor pattern 118 is formed to overlap the source electrode 110 and the drain electrode 112 to form a channel portion between the source electrode 110 and the drain electrode 112, the active layer 114, and the active layer 114. An ohmic contact layer 116 for ohmic contact between the source electrode 110 and the active layer 114 and the drain electrode 112 is formed. The thin film transistor 106 serves as a switch to charge the pixel voltage signal supplied to the data line 104 to the pixel electrode 117 in response to the gate signal supplied to the gate line 102.

The pixel electrode 117 is connected to the drain electrode 112 of the thin film transistor 106 through the contact hole 115 passing through the passivation layer 135. The pixel electrode 117 generates a potential difference from the common electrode 152 of the first array panel 160 by the charged pixel voltage. By the potential difference, the liquid crystal 180 positioned between the first array panel 130 and the second array panel 160 is rotated by dielectric anisotropy to adjust the light transmittance through the liquid crystal 180 to realize gradation. .

The storage capacitor 120 includes a front gate line 102 and a pixel electrode 117 overlapping each other with the gate insulating layer 133 and the passivation layer 135 interposed therebetween. The storage capacitor 120 allows the pixel voltage charged in the pixel electrode 117 to be stably maintained until the next pixel voltage is charged.

The gate line 102 is supplied with a scan voltage from the gate driver, and the data line 104 transmits the data voltage supplied from the data driver to the pixel electrode 117 via the thin film transistor 106.

The second array panel 160 includes a black matrix 164, a reflective pattern 154, a refractive pattern 156, and a color filter 166 sequentially formed on the second substrate 162. In addition, the second array panel 160 further includes a planarization layer 168 covering the second substrate 162 on which the black matrix 164, the reflective pattern 154, the refractive pattern 156, and the color filter 166 are formed. Can be. 3 to 5, when the liquid crystal 180 is driven by a vertical electric field, a common electrode 152 is further formed on the planarization layer 168.

The black matrix 164 is formed to overlap the thin film transistor forming region of the first array panel 130 and the region of the gate lines 102 and the data lines 104, and defines a cell region in which the color filter 166 is to be formed. Compartment.

The reflective pattern 154 is formed on the black matrix 164 in the same pattern as the black matrix 164. The reflective pattern 154 reflects the light 190 incident to the black matrix 164 toward the backlight unit 170.

The refractive pattern 156 is formed on the reflective pattern 154 so as to overlap, and has an embossed surface. The refractive pattern 156 is a light incident on the black matrix 164 area reflected by the reflective pattern 154 by causing the light 190 incident on the reflective pattern 154 to be refracted at the embossed surface when the reflective pattern 154 is reflected. The path of 190 is refracted toward the transmission region P1 of the liquid crystal panel. The light 190 passing through the transmission area P1 is reflected by the reflecting plate 174 of the backlight unit 170 to be described later, and thus may be displayed on the screen. Accordingly, the light 190 incident toward the black matrix 164 is reflected and refracted by the reflective pattern 154, the refraction pattern 156, and the reflecting plate 174 to pass through the transmission region P1, thereby providing It can contribute to brightness improvement. In addition, since the light whose path is changed to face the transmission region P1 by the refraction pattern 156 is refracted to the transmission region P1 without facing the channel portion of the thin film transistor 106, the channel portion of the thin film transistor 106 has light 190. In addition, the phenomenon of leakage current flowing through the thin film transistor 106 can be prevented as well.

The color filter 166 is formed in the cell region separated by the black matrix 164. The color filter 166 is formed for each of R, G, and B to implement R, G, and B colors.

The planarization layer 168 is formed to planarize the surface of the second substrate 162 on which the black matrix 164, the reflective pattern 154, the refractive pattern 156, and the color filter 166 are formed.

The common electrode 152 is formed to form an electric field together with the pixel electrode 117 to control the movement of the liquid crystal 180.

3 to 5 illustrate only the vertical field type liquid crystal display device. However, the reflective pattern 154 and the refractive pattern 156 according to the present invention are not limited to the vertical field type liquid crystal display device, but the common electrode 152 is applied to the first substrate 131 instead of the second substrate 162. The present invention may also be applied to a horizontal field type liquid crystal display device. In the horizontal field type liquid crystal display, the common electrode 152 and the pixel electrode 117 are formed side by side on the first substrate 131 to form a horizontal electric field between the common electrode 152 and the pixel electrode 117.

6 is a flowchart illustrating a method of manufacturing a liquid crystal display device according to the present invention. Referring to FIG. 6, a method of manufacturing a liquid crystal display according to the present invention is largely divided into a substrate patterning step S1, a liquid crystal cell forming step S3, and a backlight unit assembly step S5.

In the substrate patterning step S1, various thin film patterns are patterned on each of the first substrate and the second substrate. The substrate patterning step S1 includes a plurality of mask processes including a photolithography process and an etching process to prepare a first array panel and a second array panel. The first array panel patterns a gate line, a data line crossing the gate line, a thin film transistor connected to the gate line and the data line, a pixel electrode connected to the thin film transistor, and the like on the first substrate through a plurality of mask processes. To be prepared. In the case of the horizontal field type liquid crystal display, a common electrode parallel to the pixel electrode is further patterned on the first substrate as compared with the vertical field type liquid crystal display. The second array panel is provided by patterning a black matrix, a reflective pattern, a refractive pattern, a color filter, and the like on a second substrate through a plurality of mask processes. In the case of the vertical field type liquid crystal display, a common electrode is further formed on the second substrate as compared with the horizontal field type liquid crystal display.

In the liquid crystal cell forming step S3, the first array panel and the second array panel are bonded to face each other such that a predetermined cell gap is formed between the first array panel and the second array panel provided in the substrate patterning step S1. Forming liquid crystal in the cell gap between the array panel and the second array panel. Thereafter, the driving circuit is mounted to complete the liquid crystal panel.

The backlight unit assembly step S5 is a step of assembling the backlight unit including the light source and the reflector on the rear surface of the liquid crystal panel.

Details of the steps of preparing the second array panel will be described below with reference to FIGS. 7A to 7E.

In order to prepare the second array panel according to the present invention, as shown in FIG. 7A, the opaque material 192 and the reflective metal 194 are deposited on the second substrate 162 by a deposition method such as PECVD, spin coating, or sputtering. To form sequentially. Here, an opaque metal or an opaque resin containing chromium (Cr) is used for the opaque material 192, and a high reflectance metal such as AlNd is used for the reflective metal 194. The photoresist pattern 196 is formed on the reflective metal 194 through a photolithography process using a first mask.

The opaque material 192 and the reflective metal 194 are then etched using the photoresist pattern 196 to etch the black matrix 164 and the same pattern on the second substrate 162 as shown in FIG. 7B. Phosphorus reflection pattern 154 is formed.

Thereafter, a reflective pattern 156 having an embossed surface is formed on the reflective pattern 154 by a photolithography process using a second mask as shown in FIG. 7C. Here, the refractive pattern 156 is made of photo acryl. In addition, the second mask for forming the refractive pattern 156 includes a transmissive portion that overlaps the region where the black matrix 164 is not formed, that is, the transmissive region. The photo acryl corresponding to the transmissive portion is removed through a developing process included in the photolithography process. The remaining portion of the second mask except for the transmissive portion has a structure in which the blocking portion and the diffractive exposure portion are repeated, and the remaining photo acryl is patterned in a structure in which protrusions and groove portions having a step are repeated. Subsequently, the photoacryl with repeated protrusions and grooves is fired to form a refractive pattern 156 having an embossed surface.

On the second substrate 162 on which the black matrix 164, the reflective pattern 154, and the refractive pattern 156 are formed, as shown in FIG. 7D, red (R), green (G), and blue (B) are included. The color filter 166 is formed. The color filter 166 is formed by sequentially patterning color resins of red (R), green (G), and blue (B) using a third mask, or each pixel (R, G, It is formed by spraying and curing the color material corresponding to B) in the cell area. The planarization layer 168 for planarizing the second substrate 162 is formed by applying a transparent resin having an insulating property on the second substrate 162 on which the color filter 166 is formed.

In the case of the vertical field type liquid crystal display, as shown in FIG. 7E, indium tin oxide (ITO), tin oxide (TO), and indium zinc oxide (Indium Zinc Oxide) are formed on the planarization layer 168. The common electrode 152 is formed by applying a transparent metal material such as IZO) or indium tin zinc oxide (ITZO).

As described above, the liquid crystal display and the manufacturing method thereof according to the present invention form a reflection pattern and a refraction pattern in the black matrix area so that light incident on the black matrix area is refracted and reflected toward the transmission area to be displayed on the liquid crystal display device. To be able. Accordingly, the liquid crystal display and the manufacturing method thereof according to the present invention can use the light incident on the black matrix area to improve the brightness of the liquid crystal display.

In addition, in the present invention, since the path of the light incident on the black matrix using the reflection pattern and the refraction pattern is directed toward the transmission region, and not toward the thin film transistor channel portion of the non-transmissive region, the channel portion of the thin film transistor is activated by light to leak the current into the thin film transistor. The phenomenon of flowing can also be prevented.

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.

Claims (8)

A first array panel including a gate line formed on the first substrate, a data line crossing the gate line to define the cell region, and a pixel electrode formed in the cell region; A black matrix formed on a second substrate facing the first substrate to partition a cell region, a refractive pattern having a reflection pattern and an embossing surface formed on the black matrix, and a color filter formed in the cell region; 2 array panels; And a backlight unit including a light source for irradiating light to the first and second array panels, and a reflector to reflect the light emitted from the light source toward the first and second array panels. Device. The method of claim 1, And the black matrix pattern and the reflective pattern are formed in the same pattern. The method of claim 1, The light incident from the light source to the reflective pattern is reflected toward the embossing surface of the refractive pattern, then is refracted at the surface of the refractive pattern to pass through the cell region, and then is incident on the reflector of the backlight unit to the color filter. A liquid crystal display device, characterized in that irradiated. The method of claim 1, And the reflective pattern comprises AlNd metal. The method of claim 1, And the refractive pattern comprises photo acryl. Providing a first array panel including a gate line formed on a first substrate, a data line crossing the gate line to define the cell region, and a pixel electrode formed in the cell region; Providing a second array panel including a black matrix formed on a second substrate to define a cell region, a refractive pattern having a reflective pattern and an embossed surface superimposed on the black matrix, and color filters formed in the cell region; Steps; Bonding the first and second array panels to face each other; Assembling a backlight unit having a light source for irradiating light to the first and second array panels and a reflector to reflect light emitted from the light source toward the first and second array panels. The manufacturing method of the liquid crystal display device made into. The method of claim 6, Preparing the second array panel, Forming the black matrix and the reflective pattern on the second substrate; Forming the refractive pattern on the reflective pattern; And sequentially forming the color filter in the cell region. The method of claim 7, wherein Forming the black matrix and the reflective pattern on the second substrate is Depositing an opaque material comprising opaque metal or opaque resin comprising chromium on said second substrate; Depositing a reflective metal comprising AlNd on the opaque material; Forming a photoresist pattern on the reflective metal; And etching the opaque material and the reflective metal by using the photoresist pattern.

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