KR20070059290A - Liquid crystal display and manufacturing method thereof - Google Patents

Abstract

An LCD(Liquid Crystal Display) and a method for manufacturing the same are provided to improve the direction characteristic of light incident to the LCD, thereby improving the efficiency of light, by forming a reflecting electrode to have a plurality of protrusions each having an asymmetric structure. An LCD comprises a first substrate(110) and a reflecting electrode(194) formed above the first substrate, wherein the reflecting electrode has a plurality of protrusions. Each of the protrusions has a first inclined surface and a second inclined surface. Each of the protrusions has an asymmetric structure such that the first inclined surface has a smaller inclination than the second inclined surface. A second substrate(210) is disposed to face the first substrate, and a color filter layer(230) is formed on the second substrate.

Description

Liquid crystal display device and its manufacturing method {LIQUID CRYSTAL DISPLAY AND MANUFACTURING METHOD THEREOF}

1 is a cross-sectional view schematically illustrating a liquid crystal display according to an exemplary embodiment of the present invention.

2 illustrates reflection of light according to the protrusion structure of the reflective electrode of the liquid crystal display according to the exemplary embodiment.

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

4 and 5 are cross-sectional views of the liquid crystal display shown in FIG. 3 taken along lines IV-IV and V-V, respectively.

6 is an example of a mask used in a method of manufacturing a liquid crystal display according to an exemplary embodiment of the present invention.

7 is a cross-sectional view of a mask used in the method of manufacturing a liquid crystal display device according to an exemplary embodiment of the present invention and a pattern manufactured thereby.

8 is a laminated structure of a protective film used in the method of manufacturing a liquid crystal display according to another embodiment of the present invention.

9A to 9D are cross-sectional views illustrating a method of manufacturing a liquid crystal display according to another exemplary embodiment of the present invention.

The present invention relates to a liquid crystal display device and a manufacturing method thereof.

In general, a liquid crystal display device includes a liquid crystal layer positioned between a field generating electrode and a pair of display panels provided with a polarizing plate. The field generating electrode generates an electric field in the liquid crystal layer and the arrangement of the liquid crystal molecules changes as the intensity of the electric field changes. For example, in the state where an electric field is applied, the liquid crystal molecules of the liquid crystal layer change its arrangement to change the polarization of light passing through the liquid crystal layer. The polarizer displays a desired image by appropriately blocking or transmitting polarized light to create bright and dark areas.

Since the liquid crystal display is a light-receiving display device that does not emit light by itself, light from a lamp of a separately provided backlight unit passes through the liquid crystal layer, or light from external sources such as natural light passes through the liquid crystal layer once again. Reflects and passes the liquid crystal layer again. The former case is called a transmissive liquid crystal display device, and the latter case is called a reflective liquid crystal display device. The latter case is mainly used for small and medium size display devices. In addition, a semi-transmissive or reflective-transmissive liquid crystal display device using either a backlight device or an external light is developed according to the environment, and is mainly applied to a small and medium display device.

In the case of a small and medium-sized liquid crystal display device in which natural light is reflected from a reflective electrode and used as a light source, the user generally uses the liquid crystal display device while standing in front of the user while carrying the liquid crystal display device.

However, the amount of light incident on the small and medium-sized liquid crystal display using the reflected light of natural light as a light source is very different depending on the direction of the user. For example, when using the liquid crystal display at an eye level, the amount of light incident from the upper part of the user is much greater than the amount of light incident from the lower part or the rear of the user, which means that the liquid crystal display is displayed at the lower part or behind the user. This is because light incident on the screen of the device is blocked by the user's body.

However, a liquid crystal display device using reflected light as a light source generally has a structure of a reflective electrode in which all light incident in all directions is equally reflected in all directions.

Accordingly, an object of the present invention is to provide a liquid crystal display device and a method of manufacturing the same, which optimize light reflectivity by utilizing the direction characteristic of light incident on a portable small and medium liquid crystal display device.

According to an embodiment of the present invention, a liquid crystal display device includes a first substrate and a pixel electrode formed on the first substrate and having a plurality of protrusions, wherein the protrusions include a first inclined surface and a first inclined surface. It has two inclined surfaces, and the inclination of the first inclined surface is an asymmetric shape smaller than the inclination of the second inclined surface.

The liquid crystal display includes a gate line and a data line formed on the first substrate, a thin film transistor connected to the gate line and a data line, and a protective film formed on the first substrate and having a plurality of protrusions on a surface thereof. The pixel electrode may be connected to the thin film transistor.

The liquid crystal display may further include a second substrate facing the first substrate, and a plurality of color filters formed on the second substrate.

The liquid crystal display may further include a light blocking member formed on the second substrate, an overcoat formed on the color filter, and a common electrode formed on the overcoat.

A method of manufacturing a liquid crystal display according to an exemplary embodiment of the present invention includes preparing a substrate, forming a gate line and a data line on the substrate, and a thin film transistor connected to the gate line and the data line on the substrate. Forming a passivation layer formed on the first substrate and having a plurality of protrusions on a surface thereof, and forming a pixel electrode on the passivation layer, wherein the protrusions include a first inclined surface and a second inclined surface. The inclination of the first inclined surface is less than the inclination of the second inclined surface.

The forming of the passivation layer having a plurality of protrusions having an asymmetric shape may include applying a photosensitive organic layer on the substrate, exposing the substrate on which the organic layer is applied according to a mask pattern, developing the exposed substrate, And baking the developed substrate.

The mask pattern is divided into first and second opaque regions and a transparent region, the transparent region is surrounded by the first opaque region, and the second opaque region is formed between the first opaque region and the transparent region. It may be disposed in a separated form above the transparent region surrounded by the first opaque region.

Forming a protective film having a plurality of protrusions of the asymmetrical form may include laminating a protrusion structure layer film having a laminated structure on the substrate, irradiating ultraviolet rays on the substrate on which the protrusion structure layer film is laminated, and It may include the step of removing the support of the projection structure layer film.

The protrusion structure layer film may have a laminated structure of a support, a protrusion film, and a cover layer.

The support may be made of a transparent polyethylene terpthalate (PET) film and an acrylic layer having a plurality of protrusions formed on a surface thereof.

The polyethylene terephthalate film may have a thickness of 40 μm to 60 μm, and the acrylic layer may have a thickness of 4 μm to 5 μm.

The protrusion film may be made of a photosensitive acrylic resin, and the thickness of the protrusion film may be 2 μm to 2.5 μm.

The cover layer may be formed of a polyethylene terephthalate film having a thickness of 20 μm to 30 μm, and the cover layer may be removed in a manufacturing step of the liquid crystal display.

DETAILED DESCRIPTION Embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like parts are designated by like reference numerals throughout the specification. When a part of a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the other part being "right over" but also another part in the middle. On the contrary, when a part is "just above" another part, there is no other part in the middle.

A liquid crystal display according to an exemplary embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view schematically illustrating a cross section of a liquid crystal display according to an exemplary embodiment of the present invention.

As illustrated in FIG. 1, the liquid crystal display includes a thin film transistor array panel 100 and a common electrode panel 200 facing each other, and a liquid crystal layer 3 interposed therebetween.

In the thin film transistor array panel 100, a switching element (not shown), a passivation layer 180, and a pixel electrode 191 are formed on the insulating substrate 110. The pixel electrode 191 includes a transparent electrode 192 and a reflective electrode 194 on a portion of the transparent electrode 192. A plurality of protrusions are formed on the surface of the passivation layer 180 to induce a protrusion pattern on the reflective electrode 194. The projection pattern of the reflective electrode 194 induces diffuse reflection of light to prevent the object from being reflected on the screen. The projection of the reflective electrode 194 has a first inclined surface and a second inclined surface, and the inclination of the first inclined surface is smaller than that of the second inclined surface, so that it is gentle in the first direction and has a steep inclination in the second direction. In this case, the first direction portion having a gentle slope is a region where a lot of light is incident, and corresponds to an upper portion of the liquid crystal display.

In the common electrode display panel 200, the color filter 220 and the common electrode 270 are formed on the insulating substrate 210.

The transflective liquid crystal display may be partitioned into a transmissive area TA and a reflective area RA defined by the transparent electrode 192 and the reflective electrode 194, respectively. Specifically, the portion of the thin film transistor array panel 100, the common electrode display panel 200, the liquid crystal layer 3, and the like positioned below and below the exposed portion of the transparent electrode 192 becomes the transmission area TA, and the reflective electrode ( 194) The upper and lower portions become the reflection area RA. In the transmissive area TA, light incident on the back side of the liquid crystal display, that is, the thin film transistor array panel 100, passes through the liquid crystal layer 3 and exits the front side, that is, toward the common electrode display panel 200, to perform display. In the area RA, the light enters the liquid crystal layer 3, enters the liquid crystal layer 3, is reflected by the reflective electrode 194, passes through the liquid crystal layer 3, and exits to the front surface.

Since the average thickness of the color filter 230 of the reflective area RA is about 1/2 of the average thickness of the color filter 230 of the transmissive area TA, the average thickness of the color filter 230 passing through the reflective area RA and the transmissive area TA is different. The color tone of light can be constant.

The projection structure of the reflective electrode 194 has an asymmetric shape having a first inclined surface and a second inclined surface having different inclination inclinations from each other, and the asymmetrical shape is formed depending on the amount of incident light along the direction of the liquid crystal display. This is to change the amount of light reflected accordingly.

This will be described in more detail with reference to FIG. 2. 2 illustrates reflection of light according to the protrusion structure of the reflective electrode of the liquid crystal display according to the exemplary embodiment.

Referring to FIG. 2, the substrate 110 of the liquid crystal display is disposed at a position facing the user's field of view. That is, since a user of a small and medium-sized liquid crystal display device generally uses the liquid crystal display device in front of its own field of view, the size of light incident on the liquid crystal display device is the maximum.

As shown in FIG. 2, since the protrusion structure of the reflective electrode 194 of the liquid crystal display according to the exemplary embodiment of the present invention has a small inclination angle at a portion where light is mainly incident, it is gently inclined, the incident light (a To f) are reflected at the surface of the reflective electrode 194 to advance toward the user's field of view. On the contrary, if the projection structure of the reflective electrode 194 is formed so that the upper and lower sides of the user are symmetrical, the light (a to f) incident from the upper side is reflected in all directions, and the reflected light is directed toward the user's field of view. The amount of light is reduced compared to the embodiment of the present invention.

Next, a specific example of the liquid crystal display shown in FIG. 1 will be described in more detail with reference to FIGS. 3 to 5.

3 is a layout view of a liquid crystal display according to an exemplary embodiment of the present invention, and FIGS. 4 and 5 are cross-sectional views of the liquid crystal display shown in FIG. 3 taken along lines IV-IV and V-V, respectively. .

The liquid crystal display according to the present exemplary embodiment includes a thin film transistor array panel 100, a common electrode panel 200 facing the thin film transistor array panel 100, and a liquid crystal layer 3 including liquid crystal molecules interposed therebetween.

First, the thin film transistor array panel 100 will be described.

A plurality of gate lines 121 and a plurality of storage electrode lines 131 are formed on an insulating substrate 110 made of transparent glass or plastic.

The gate line 121 transmits a gate signal and mainly extends in a horizontal direction. Each gate line 121 includes a plurality of gate electrodes 124 protruding upward and end portions 129 having a large area for connection with another layer or an external driving circuit. A gate driving circuit (not shown) for generating a gate signal may be mounted on a flexible printed circuit film (not shown) attached to the substrate 110 or directly mounted on the substrate 110, It may be integrated into the substrate 110. When the gate driving circuit is integrated on the substrate 110, the gate line 121 may extend to be directly connected to the gate driving circuit.

The storage electrode line 131 receives a predetermined voltage and almost extends in parallel with the gate line 121. Each storage electrode line 131 is positioned between two adjacent gate lines 121 and is close to a lower side of the two gate lines 121. The storage electrode line 131 includes a storage electrode 137 extending up and down. However, the shape and arrangement of the storage electrode line 131 may be modified in various ways.

The gate line 121 and the storage electrode line 131 may be formed of aluminum-based metal such as aluminum (Al) or aluminum alloy, silver-based metal such as silver (Ag) or silver alloy, copper-based metal such as copper (Cu) or copper alloy, or molybdenum ( It may be made of molybdenum-based metals such as Mo) or molybdenum alloy, chromium (Cr), tantalum (Ta) and titanium (Ti). However, they may have a multilayer structure including two conductive films (not shown) having different physical properties. One of the conductive films is made of a metal having low resistivity, such as aluminum-based metal, silver-based metal, or copper-based metal, so as to reduce signal delay or voltage drop. In contrast, other conductive films are made of other materials, particularly materials having excellent physical, chemical, and electrical contact properties with indium tin oxide (ITO) and indium zinc oxide (IZO), such as molybdenum-based metals, chromium, tantalum, and titanium. Good examples of such a combination include a chromium bottom film, an aluminum (alloy) top film, and an aluminum (alloy) bottom film and a molybdenum (alloy) top film. However, the gate line 121 and the storage electrode line 131 may be made of various other metals or conductors.

Side surfaces of the gate line 121 and the storage electrode line 131 are inclined with respect to the surface of the substrate 110, and the inclination angle is preferably about 30 ° to about 80 °.

A gate insulating layer 140 made of silicon nitride (SiNx) or silicon oxide (SiOx) is formed on the gate line 121 and the storage electrode line 131.

A plurality of linear semiconductors 151 made of hydrogenated amorphous silicon (hereinafter referred to as a-Si) or polysilicon are formed on the gate insulating layer 140. The linear semiconductor 151 mainly extends in the longitudinal direction, includes a plurality of projections 154 extending toward the gate electrode 124, and an extension 157 extends from the projection 154. The linear semiconductor 151 has a wider width in the vicinity of the gate line 121 and the storage electrode line 131 and covers them widely.

A plurality of linear and island ohmic contacts 161 and 165 are formed on the semiconductor 151. The ohmic contacts 161 and 165 may be made of a material such as n + hydrogenated amorphous silicon in which n-type impurities such as phosphorus are heavily doped, or may be made of silicide. The linear ohmic contact 161 has a plurality of protrusions 163, and the protrusion 163 and the island-type ohmic contact 165 are paired and disposed on the protrusion 154 of the semiconductor 151.

Side surfaces of the semiconductor 154 and the ohmic contacts 163 and 165 are also inclined with respect to the surface of the substrate 110, and the inclination angle is about 30 ° to 80 °.

A plurality of data lines 171 and a plurality of drain electrodes 175 separated therefrom are formed on the ohmic contacts 163 and 165 and the gate insulating layer 140.

The data line 171 transmits a data signal and mainly extends in the vertical direction to cross the gate line 121. Each data line 171 includes a plurality of source electrodes 173 extending toward the gate electrode 124 and an end portion 179 having a large area for connection with another layer or an external driving circuit. A data driving circuit (not shown) for generating a data signal is mounted on a flexible printed circuit film (not shown) attached to the substrate 110, directly mounted on the substrate 110, or integrated in the substrate 110. Can be. When the data driving circuit is integrated on the substrate 110, the data line 171 may be extended to be directly connected to the data driving circuit.

The drain electrode 175 is separated from the data line 171 and faces the source electrode 173 with respect to the gate electrode 124. Each drain electrode 175 has one wide end portion 177 and the other end having a rod shape. The wide end portion 177 overlaps the sustain electrode 137, and the rod-shaped end portion is partially surrounded by the bent source electrode 173.

One gate electrode 124, one source electrode 173, and one drain electrode 175 together with the protrusion 154 of the semiconductor 151 form one thin film transistor (TFT). A channel of the transistor is formed in the protrusion 154 between the source electrode 173 and the drain electrode 175.

The data line 171 and the drain electrode 175 are preferably made of a refractory metal such as molybdenum, chromium, tantalum, and titanium, or an alloy thereof, and include a refractory metal film (not shown) and a low resistance conductive film. It may have a multilayer structure including (not shown). Examples of the multilayer structure include a double layer of chromium or molybdenum (alloy) lower layer and an aluminum (alloy) upper layer, and a triple layer of molybdenum (alloy) lower layer and aluminum (alloy) interlayer and molybdenum (alloy) upper layer. However, the data line 171 and the drain electrode 175 may be made of various metals or conductors.

The side of the data line 171 and the drain electrode 175 may also be inclined at an inclination angle of about 30 ° to about 80 ° with respect to the surface of the substrate 110.

The ohmic contacts 163 and 165 exist only between the semiconductor 154 thereunder and the data line 171 and the drain electrode 175 thereon to lower the contact resistance therebetween. Although the linear semiconductor 151 is narrower than the data line 171 in most places, as described above, the width of the linear semiconductor 151 is widened at the portion where it meets the gate line 121 to smooth the profile of the surface, thereby disconnecting the data line 171. prevent. The semiconductor 154 includes an exposed portion 154 between the source electrode 173 and the drain electrode 175 and not covered by the data line 171 and the drain electrode 175.

A passivation layer 180 is formed on the data line 171, the drain electrode 175, and the exposed semiconductor 154. The passivation layer 180 includes a lower layer 180p made of an inorganic insulator such as silicon nitride or silicon oxide and an upper layer 180q made of an organic insulator. The upper passivation layer 180q preferably has a dielectric constant of 4.0 or less, may have photosensitivity, and protrusions are formed on the surface thereof. In addition, an opening that exposes a portion of the lower passivation layer 180p is formed in the upper passivation layer 180q. However, the passivation layer 180 may have a single layer structure made of an inorganic insulator or an organic insulator.

In the passivation layer 180, a plurality of contact holes 182 and 185 exposing the end portion 179 and the drain electrode 175 of the data line 171 are formed, respectively, and the passivation layer 180 and the gate insulating layer are formed. A plurality of contact holes 181 exposing the end portion 129 of the gate line 121 are formed at 140.

A plurality of pixel electrodes 191 and a plurality of contact assistants 81 and 82 are formed on the passivation layer 180.

Each pixel electrode 191 is curved along the protrusion structure of the upper passivation layer 180q and includes a transparent electrode 192 and a reflective electrode 194 thereon. The transparent electrode 192 is made of a transparent conductive material such as ITO or IZO, and the reflective electrode 194 is made of a reflective metal such as aluminum, silver, chromium or an alloy thereof. However, the reflective electrode 194 has a low resistance reflective upper film (not shown) such as aluminum, silver, or an alloy thereof, and a lower film (not shown) having good contact properties with ITO or IZO such as molybdenum-based metal, chromium, tantalum, and titanium. ) May have a double membrane structure.

The reflective electrode 194 exists only on a portion of the transparent electrode 192 to expose another portion of the transparent electrode 192, and the exposed portion of the transparent electrode 192 is positioned in the opening 195 of the upper passivation layer 180q. do.

The pixel electrode 191 is physically and electrically connected to the drain electrode 175 through the contact hole 185 and receives a data voltage from the drain electrode 175. The pixel electrode 191 to which the data voltage is applied is formed between the two electrodes 191 and 270 by generating an electric field together with the common electrode 270 of the common electrode display panel 200 to which the common voltage is applied. The direction of the liquid crystal molecules of the liquid crystal layer 3 is determined. The polarization of light passing through the liquid crystal layer 3 varies according to the direction of the liquid crystal molecules determined as described above. The pixel electrode 191 and the common electrode 270 form a capacitor (hereinafter, referred to as a "liquid crystal capacitor") to maintain an applied voltage even after the thin film transistor is turned off.

The transflective liquid crystal display device including the thin film transistor array panel 100, the common electrode display panel 200, the liquid crystal layer 3, and the like is a transmissive area TA defined by the transparent electrode 192 and the reflective electrode 194, respectively. And a reflection area RA. Specifically, the portion located above and below the transmission window 195 becomes the reflection area RA.

In the transmissive area TA, light is incident on the back side of the liquid crystal display, that is, the thin film transistor array panel 100, passes through the liquid crystal layer 3 and exits the front side, that is, toward the common electrode display panel 200. In the reflective area RA, the light enters the liquid crystal layer 3, enters the liquid crystal layer 3, is reflected by the reflective electrode 194, passes through the liquid crystal layer 3, and exits to the front surface. At this time, the bending of the reflective electrode 194 induces diffuse reflection of light to prevent the object from being reflected on the screen.

Since the upper passivation layer 180q is not present in the transmission area TA, the thickness of the liquid crystal layer 3 or the cell gap in the transmission area TA is greater than the cell gap in the reflection area RA. In particular, it is preferable that the cell spacing in the transmission area TA is twice the cell spacing in the reflection area RA.

The pixel electrode 191 and the drain electrode 175 electrically connected thereto overlap the storage electrode line 131. A capacitor in which the pixel electrode 191 and the drain electrode 175 electrically connected thereto overlap with the storage electrode line 131 is called a "storage capacitor", and the storage capacitor enhances the voltage holding capability of the liquid crystal capacitor. .

The contact auxiliary members 81 and 82 are connected to the end portion 129 of the gate line 121 and the end portion 179 of the data line 171 through the contact holes 181 and 182, respectively. The contact auxiliary members 81 and 82 compensate for and protect the adhesion between the end portion 129 of the gate line 121 and the end portion 179 of the data line 171 and the external device.

Next, the common electrode display panel 200 will be described.

A light blocking member 220 is formed on a substrate 210 made of an insulating material such as transparent glass or plastic. The light blocking member 220 is also referred to as a black matrix and defines a plurality of opening regions facing the pixel electrode 191 while preventing light leakage between the pixel electrodes 191.

A plurality of color filters 230 are also formed on the substrate 210 and are arranged to almost fit into the opening region surrounded by the light blocking member 220. The color filter 230 may extend in the vertical direction along the pixel electrode 191 to form a stripe. Each color filter 230 may display one of primary colors such as three primary colors of red, green, and blue.

The average thickness of the color filter 230 of the reflection area RA is preferably about 1/2 of the average thickness of the color filter 230 of the transmission area TA. The color tone of each passing light may be constant.

An overcoat 250 is formed on the color filter 230 and the light blocking member 220. The overcoat 250 may be made of an (organic) insulator, protects the color filter 230, prevents the color filter 230 from being exposed, and provides a flat surface.

In the present exemplary embodiment, the cell gap between the reflection area RA and the transmission area TA is adjusted by forming the transmission window 195, but is disposed in the reflection area RA of the color filter display panel 200 of the liquid crystal display device. The cell gap may be adjusted by forming the overcoat 250 thicker than the overcoat 250 disposed in the transmission area TA.

The common electrode 270 is formed on the overcoat 250. The common electrode 270 is preferably made of a transparent conductive conductor such as ITO or IZO.

An alignment layer (not shown) for aligning the liquid crystal layer 3 is coated on the inner surfaces of the display panels 100 and 200, and one or more polarizers are disposed on the outer surfaces of the display panels 100 and 200. (Not shown) is provided.

The liquid crystal layer 3 is vertically or horizontally aligned.

The liquid crystal display further includes a plurality of elastic spacers (not shown) that hold the thin film transistor array panel 100 and the common electrode panel 200 to form a gap therebetween.

The liquid crystal display may further include a sealant (not shown) for coupling the thin film transistor array panel 100 and the common electrode panel 200. The sealing material is positioned at the edge of the common electrode display panel 200.

Next, a method of forming the protrusion structure of the passivation layer 180 inducing the protrusion structure of the reflective electrode 194 of the liquid crystal display according to the exemplary embodiment of the present invention will be described in more detail with reference to FIGS. 6 and 7. Explain.

A photolithography process is used to form protrusions on a surface of a reflective region electrode of a liquid crystal display according to an exemplary embodiment of the present invention. An example of a mask used in such a photolithography process is shown in FIG. A cross sectional view of and a cross sectional view of a projection that can be produced therefrom is shown in FIG. 7.

Referring to FIG. 6, the surface of the mask 950 is divided into a first opaque region 951 through which light does not pass, a transparent region 952 through which light passes, and a second opaque region 953, and a transparent region 952. ) Is surrounded by the first opaque region 951.

Also, as shown in FIG. 6, the second opaque region 953 of the mask 950 is formed between the first opaque region 951 and the transparent region 952, which is surrounded by the opaque region 951. The regions 952 are arranged above each other in a form separated from each other.

FIG. 7 is a cross-sectional view of the protrusion 183 formed on the passivation layer 180 of the liquid crystal display according to the exemplary embodiment of the present invention and the mask 950 disposed thereon. The mask 950 includes a first opaque region 951 that cannot pass through light, a first transparent region 952 that passes through light, a second opaque region 953 that does not pass through light, and a second transparent through light. Regions 954 are arranged one after the other.

The width d1 of the first transparent region 952 is greater than the width d2 of the second transparent region 954. Also, the width of the first opaque region 951 is larger than the second opaque region 953.

The amount of light reaching the photosensitive protective layer 180 in the exposure step of the photolithography process of patterning the protective layer 180 by using the mask 950 according to the embodiment of the present invention is the first and second transparent regions 952 and 954. It depends on the area of, which is the largest in the large first transparent region 952 and rapidly decreases in the opaque region 953, then increases in the second transparent region 954 and increases in the wide opaque region 951. By the smallest. Therefore, the organic film is most removed in the first transparent region 952 where the light reaches the most and the organic film is relatively removed in the second transparent region where the light reaches the least, and is not removed in the opaque regions 951 and 953. The photosensitive film is reflowed into the first and second transparent regions 952 and 954 to form protrusions 183 in the form shown below in FIG.

As such, when the protrusion 183 of the passivation layer 180 is formed by the photolithography process using the mask 950 according to the embodiment of the present invention, the second opaque region 953 has a gentle inclination. It will have an asymmetrical shape.

In the above, the case where the organic film which has positive photosensitivity is used is illustrated, and when the organic film which has negative photosensitivity is used, the arrangement | positioning of the transparent part 952 and the opaque part 951 of a mask is reversed from FIG. 6 and FIG. .

Next, a method of forming protrusions on the surface of the reflective electrode 194 according to another exemplary embodiment of the present invention will be described with reference to FIGS. 8 to 9D.

8 is a laminated structure of a protrusion structure used in the method of manufacturing a liquid crystal display according to another embodiment of the present invention, and FIGS. 9A to 9D illustrate a method of manufacturing a liquid crystal display according to another embodiment of the present invention. A cross-sectional view is shown step by step.

As shown in FIG. 8, the protruding structure layer 183 has a film form in which a support 183a, a protruding film 183c, and a cover layer 183b are stacked. The support 183a may be formed of a transparent polyethylene terpthalate (PET) film and an acrylic layer having a protrusion structure formed on the surface thereof. The polyethylene terephthalate film has a thickness of about 50 μm and the thickness of the acrylic layer. May be about 4.5 μm. The projection film 183c may be made of a photosensitive acrylic resin and may have a thickness of about 2.3 μm. Also, the cover layer 183b may be a polyethylene terephthalate film having a thickness of about 25 μm. The cover layer 183b is used to protect the projection film 183c and is removed in the manufacturing step of the liquid crystal display device.

The projection film 183c is inclined asymmetrically in both directions, such as the projections formed on the protective film 180 of the liquid crystal display of the present invention.

Next, a method of inducing protrusions on the surface of the reflective film 194 using the protrusion structure layer 183 of FIG. 8 will be described with reference to FIGS. 9A to 9D.

Referring to FIG. 9A, the protrusion structure layer 183, which is already manufactured in a film form, is cut to a suitable size, and the cover layer 183b is removed, and then laminated on the substrate 110.

At this time, the projection structure layer 183 in the form of film is placed on the substrate 110, and the rollers 961 and 962 respectively disposed above and below the substrate 110 are rotated in different directions as indicated by small arrows. Move in the direction of the arrow to apply pressure. The temperature of the rollers 961 and 962 may be 100 ° C to 140 ° C.

As shown in FIG. 9B, ultraviolet rays (UV) are irradiated onto the substrate 110 on which the projection film 183 is laminated so that the projection film 183c is well adhered to the substrate 110.

Next, referring to FIG. 9C, after the support 183b is removed, the reflective electrode 194 is deposited on the remaining protrusion film 183c by sputtering or the like, as shown in FIG. 9D, according to an exemplary embodiment of the present invention. It is possible to form a plurality of protrusions having an asymmetric slope on the surface of the reflective electrode 194 of the device.

According to the present invention, a plurality of asymmetrical projections having different inclination inclinations in both directions are formed on the surface of the reflective electrode of the liquid crystal display device, taking advantage of the direction characteristic of light incident on the portable small and medium liquid crystal display device. The light incident from the upper side of the user is mainly reflected toward the user's field of view, thereby increasing the efficiency of the light.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims (13)

A first substrate, and A pixel electrode formed on the first substrate and having a plurality of protrusions; The protrusion has a first inclined surface and a second inclined surface, and the inclination of the first inclined surface is an asymmetric shape smaller than the inclination of the second inclined surface. In claim 1, A gate line and a data line formed on the first substrate; A thin film transistor connected to the gate line and the data line, and A protective film formed on the first substrate and having a plurality of protrusions on a surface thereof; The pixel electrode is connected to the thin film transistor. In claim 2, A second substrate facing the first substrate, and And a plurality of color filters formed on the second substrate. In claim 3, A light blocking member formed on the second substrate, An overcoat formed on the color filter, and And a common electrode formed on the overcoat. Preparing the substrate, Forming a gate line and a data line on the substrate; Forming a thin film transistor connected to the gate line and the data line on the substrate; Forming a protective film formed on the first substrate and having a plurality of protrusions on a surface thereof; and Forming a pixel electrode on the passivation layer, The protrusion has a first inclined surface and a second inclined surface, and the inclination of the first inclined surface is an asymmetric shape smaller than the inclination of the second inclined surface. In claim 5, Forming a protective film having a plurality of protrusions of the asymmetric type Applying a photosensitive organic film on the substrate, Exposing the substrate on which the organic film is applied according to a mask pattern; Developing the exposed substrate, and A method of manufacturing a liquid crystal display comprising baking the developed substrate. In claim 6, The mask pattern is divided into first and second opaque regions and transparent regions, The transparent region is surrounded by the first opaque region, The second opaque region is formed between the first opaque region and the transparent region, and is disposed in a separated form above the transparent region surrounded by the first opaque region. In claim 5, Forming a protective film having a plurality of protrusions of the asymmetric type Laminating the protrusion structure layer film of the laminated structure on the substrate; Irradiating ultraviolet rays onto the substrate on which the protrusion structure layer film is laminated; and Removing the support of the protruding structure layer film. In claim 8, The projection structure layer film has a laminated structure of a support, a projection film, and a cover layer. In claim 9, And the support comprises a transparent polyethylene terpthalate (PET) film and an acrylic layer having a plurality of protrusions formed on a surface thereof. In claim 10, The polyethylene terephthalate film has a thickness of 40 μm to 60 μm, and the acrylic layer has a thickness of 4 μm to 5 μm. In claim 10, The projection film is made of a photosensitive acrylic resin, the thickness of the projection film is a liquid crystal display device manufacturing method of 2.0㎛ to 2.5㎛. In claim 10, And the cover layer is made of a polyethylene terephthalate film having a thickness of 20 μm to 30 μm, and the cover layer is removed in a manufacturing step of the liquid crystal display device.

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