Display device having a domain-forming layer with a depression pattern and method of manufacturing the same

A display device may include a first substrate, a second substrate, and a liquid crystal layer. The first substrate may include a domain-forming layer including a depression pattern for forming a liquid crystal domain in a pixel area and a pixel electrode formed on the domain-forming layer. The second substrate may face the first substrate. The second substrate may include a common electrode formed on the entire surface thereof. The liquid crystal layer may be disposed between the first substrate and the second substrate. The liquid crystal layer may include a reactive mesogen (RM) which fixes liquid crystal molecules formed in the liquid crystal domain. Since a liquid crystal domain may be formed without a separate pattern on a common electrode, a display device having an enhanced aperture ratio and an enhanced viewing angle may be manufactured.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority from and the benefit of Korean Patent Application No. 10-2009-0010026, filed on Feb. 9, 2009, which is hereby incorporated for all purposes as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Exemplary embodiments of the present invention relate to liquid crystal display devices and methods of manufacturing the same.

2. Description of the Background

Generally, a liquid crystal display (LCD) panel may include an array substrate, an opposite substrate facing the array substrate, and a liquid crystal layer interposed between the array substrate and the opposite substrate. A plurality of switching elements for driving pixel areas may be formed on the array substrate. The LCD panel may display an image by controlling transmissivity when a voltage is applied to the liquid crystal layer interposed between two substrates.

In a patterned vertical alignment (PVA) mode of an LCD device, liquid crystal molecules may be arranged in different directions by using a patterned transmissive electrode to form a liquid crystal domain, so that a viewing angle of the LCD device may be enhanced. To manufacture the PVA-mode LCD device, a process of forming the patterned transmissive electrode may be required. Moreover, in another type of the PVA mode, a protrusion may be formed on the opposite substrate and a common electrode layer may be formed on the opposite substrate on which the protrusion is formed, so that a liquid crystal domain providing an enhanced viewing angle of the LCD device may be formed. However, a separate process for forming the protrusion may be required.

As described above, in order to form a liquid crystal domain in a PVA-mode LCD device, a process of patterning a transmissive electrode and/or a process of forming a protrusion may be performed, thereby leading to a greater number of steps in the manufacturing process of an LCD device. Furthermore, patterning of the transmissive electrode and forming of the protrusion may reduce the aperture ratio of the LCD device. Moreover, in an assembly process of a display substrate and the opposite substrate, misalignment of the display substrate and the opposite substrate may generate misalignment of patterns of the display substrate's pixel electrode and the opposite substrate's common electrode, so that a liquid crystal domain is not appropriately formed.

SUMMARY OF THE INVENTION

Exemplary embodiments of the present invention provide a display device and a method of manufacturing the display device with greater manufacturing efficiency and display quality.

Exemplary embodiments of the present invention disclose a display device comprising a first substrate, a second substrate, and a liquid crystal layer. The first substrate comprises a domain-forming layer comprising a depression pattern to form a liquid crystal domain in a pixel area and a pixel electrode. The second substrate faces the first substrate. The second substrate comprises a common electrode. The liquid crystal layer is disposed between the first substrate and the second substrate. The liquid crystal layer comprises a reactive mesogen (RM) to fix liquid crystal molecules forming a liquid crystal domain.

Other exemplary embodiments of the present invention disclose a display device comprising a first substrate, a second substrate, and a liquid crystal layer. The first substrate comprises a pixel electrode having an opening pattern to form a liquid crystal domain on a pixel area. The second substrate faces the first substrate. The second substrate comprises a common electrode. The liquid crystal layer is disposed between the first substrate and the second substrate. The liquid crystal layer comprises a reactive mesogen to fix liquid crystal molecules in the liquid crystal domain.

Other exemplary embodiments of the present invention disclose a method of manufacturing a display device. The method comprises manufacturing a first substrate comprising a domain-forming layer comprising a depression pattern to form a liquid crystal domain in a pixel area and a pixel electrode formed on the domain-forming layer. The method further comprises manufacturing a second substrate facing the first substrate. The second substrate comprises a common electrode. The method further comprises disposing a liquid crystal composition material comprising liquid crystal molecules and reactive mesogen monomers between the first substrate and the second substrate. The method further comprises forming a liquid crystal layer by applying light to the liquid crystal molecules and the reactive mesogen monomers disposed between the first substrate and the second substrate. A first voltage is applied to the common electrode and a second voltage is applied to the pixel electrode.

Other exemplary embodiments of the present invention disclose a method of manufacturing a display device. The method comprises manufacturing a first substrate comprising a pixel electrode having an opening pattern to form a liquid crystal domain in a pixel area. The method further comprises manufacturing a second substrate facing the first substrate. The second substrate comprises a common electrode. The method further comprises forming a liquid crystal layer by applying light to liquid crystal molecules and reactive mesogen monomers disposed between the first substrate and the second substrate. A first voltage is applied to the common electrode and a second voltage is applied to the pixel electrode.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Hereinafter, exemplary embodiments of the present invention will be explained in detail with reference to the accompanying drawings and following examples.

FIG. 1is a plan view illustrating a display device according to some exemplary embodiments of the present invention.

FIG. 2Ais a cross-sectional view taken along a line I-I′ ofFIG. 1, andFIG. 2Bis a cross-sectional view taken along a line II-IF ofFIG. 1.

FIG. 2AandFIG. 2Bshow, states of a reactive mesogen (RM) and liquid crystal molecules of non-electric field in which a voltage is not applied between a pixel electrode and a common electrode.

Referring toFIG. 1,FIG. 2AandFIG. 2B, a display device may include a first substrate100, a second substrate200, and a liquid crystal layer300interposed between the first substrate100and the second substrate200.

The first substrate100may include a first base substrate110, first and second gate lines GL1and GL2, a storage line STL, a gate insulation layer120, first and second data lines DL1and DL2, a thin-film transistor (TFT) SW that may be a switching element in some cases, a passivation film140, a domain-forming layer150, a pixel electrode PE, and a first alignment layer AL1.

The first and second gate lines GL1and GL2may be extended along a first direction D1on the first base substrate110. In some cases, the first and second gate lines GL1and GL2may be arranged in parallel with a second direction D2that is different from the first direction D1. The second direction D2may be substantially perpendicular to the first direction D1. The storage line STL may be disposed between the first and second gate lines GL1and GL2and may extend along the first direction D1. The gate insulation layer120may be formed on the first base substrate110to cover the first and second gate lines GL1and GL2and the storage line STL. In some cases, the first and second data lines DL1and DL2may extend along the second direction D2on the gate insulation layer120. In some cases, the first and second data lines DL1and DL2may be arranged along the first direction D1in parallel with each other. The first and second data lines DL1and DL2may cross each of the first and second gate lines GL1and GL2and the storage line STL. The first substrate100may include a plurality of pixel areas P formed by crossing of the first and second gate lines GL1and GL2and the first and second data lines DL1and DL2. The pixel electrode PE may be formed on the pixel areas P.

The TFT SW may include a first gate electrode GE connected to the first gate line GL1; an active pattern AP formed on the gate insulation layer120; a source electrode SE overlapping, at least partially, the active pattern AP and being connected to the first data line DL1; a drain electrode DE overlapping, at least partially, the pixel area P and being spaced apart from the source electrode SE; and a contact electrode CNT extending from the drain electrode DE to the pixel area P. The TFT SW may include a semiconductor layer130aand an ohmic contact layer130bsequentially formed on the gate insulation layer120. The contact electrode CNT may extend from the drain electrode DE to the storage line STL. The contact electrode CNT may overlap the storage line STL.

The passivation film140may be formed on the gate insulation layer120to cover the first and second data lines DL1and DL2, the source electrode SE, the drain electrode DE, and the contact electrode CNT.

The domain-forming layer150may be formed on the passivation film140. The domain-forming layer150may planarize the first substrate100. The domain-forming layer150may include a depression pattern152that may be depressed from a surface of the domain-forming layer150toward the first substrate110. The depression pattern152may be formed in the pixel area P to yield a liquid crystal domain of the pixel area P. The depression pattern152may be formed in the domain-forming layer150in a dot shape. The depression pattern152may extend to the contact electrode CNT. The depression pattern152may be a dot-shaped hole, which may expose a portion of the contact electrode CNT. Even though the depression pattern152is formed as a dot-shaped hole, light leakage where the depression pattern152is formed may be prevented. In some cases, the domain-forming layer150may include an organic material. In some cases, the domain-forming layer150may include an inorganic material. In some cases, the domain-forming layer150may include an organic layer formed from the organic material, an inorganic layer formed from the inorganic material, and the depression pattern152formed on the organic layer or the inorganic layer.

The pixel electrode PE may be formed on the domain-forming layer150in the pixel area P. The pixel electrode PE may include an optically transparent and electrically conductive material. The pixel electrode PE may be formed to cover the depression pattern152. In some cases, the entire depression pattern152may be covered by the pixel electrode PE. The pixel electrode PE may contact the contact electrode CNT through the depression pattern152, thereby electrically connecting the pixel electrode PE to the TFT SW. An area of the pixel electrode PE on the depression pattern152may be relatively wider than an area of the pixel electrode PE formed on a planar area of the domain-forming layer150. Accordingly, when an electric field is formed between the first substrate100and the second substrate200, an electric field intensity of an area adjacent to the depression pattern152may be relatively greater than an electric field intensity of the planar area in which the depression pattern152is not formed.

In some cases, the first alignment layer AL1may be formed on the entire surface of the first base substrate110including the pixel electrode PE. In some cases, the first alignment layer AL1may be formed on part of the surface of the first base substrate110including the pixel electrode PE.

The second substrate200may include a second base substrate210facing the first substrate100, a black matrix pattern220, a first color filter232, a second color filter234, a third color filter236, an overcoating layer240, a common electrode layer250, and a second alignment layer AL2. In some cases, the overcoating layer240may be omitted from the second substrate200.

The black matrix pattern220may be formed on the second base substrate210in an area that corresponds to the area in which the first and second gate lines GL1and GL2, the first and second data lines DL1and DL2, and the TFT SW are formed. The first, second and third color filters232,234, and236may be formed on the second base substrate210. The black matrix pattern220may be placed between the color filters232,234, and236. For example, the first color filter232may be formed on the second base substrate210in an area corresponding to the pixel area P on which the pixel electrode PE is formed. The second color filter234may be formed in the first direction D1, and the third color filter236may be formed in an opposite direction of the first direction D1. The overcoating layer240may be formed on the second base substrate210on which the black matrix pattern220and the first, second and third color filters232,234and236are formed. The overcoating layer240may planarize the second substrate200.

The common electrode250may be formed on the overcoating layer240. The common electrode250may include an optically transparent and electrically conductive material. The common electrode250may be formed on the second substrate200without a separate depression pattern being formed thereon. In some cases, the common electrode250may cover an entire surface of the second substrate200.

The second alignment layer AL2may be formed on the common electrode250, and may be formed, in some cases, on the entire surface of the second substrate200.

The liquid crystal layer300may be disposed between the first substrate100and the second substrate200. The liquid crystal layer300may include the liquid crystal molecules310and an RM curing material320. An electric field may be generated between the pixel electrode PE and the common electrode250. An arrangement of the liquid crystal molecules310may be altered by the electric field via the pixel electrode PE and depression pattern152, so that a transmissivity may be adjusted. The liquid crystal molecules310may have negative dielectric anisotropy.

When a voltage is not applied to the pixel electrode PE and the common electrode250, a long axis of the liquid crystal molecules310adjacent to the first substrate100and/or the second substrate200may be arranged substantially perpendicular to a surface of the first base substrate110and/or a surface of the second base substrate210. With respect to a surface of a side wall of the domain-forming layer150which forms the depression pattern152, a long axis of the liquid crystal molecules310adjacent to the depression pattern152may be arranged perpendicular to a surface of the side wall.

The RM curing material320may be disposed along the liquid crystal molecules310adjacent to the pixel electrode PE and/or the common electrode250. For example, the RM curing material320may be disposed along the liquid crystal molecules310adjacent to the first alignment layer AL1and/or the second alignment layer AL2.

Even though an electric field may not be applied to the pixel electrode PE and the common electrode250, the RM curing material320may maintain a pretilt state with respect to the surface of the first base substrate110and/or the surface of the second base substrate210. A plurality of RM monomers330(refer toFIG. 3E) may be polymerized by external light during a manufacturing process of the display device, so that the RM curing material320may be formed.

FIG. 2Cis a cross-sectional view showing a state in which a voltage is applied to the display device ofFIG. 2B.

Referring toFIG. 2C, when an electric field is formed between the pixel electrode PE and the common electrode250, a direction of the electric field inside the pixel area P may be perpendicular to a surface of the first substrate100and/or the second substrate200.

In some cases, the direction of the electric field may be curved between an end portion of the pixel electrode PE and the common electrode250. The direction of the electric field may also be curved between an end portion of another pixel electrode adjacent to the pixel electrode PE and the common electrode250. Accordingly, in an area adjacent to the pixel electrodes PE, the liquid crystal molecules310may be arranged to diffuse towards the adjacent portion of the common electrode250, so that a liquid crystal domain between the adjacent pixel areas P may be divided.

An electric field in an area adjacent to the depression pattern152may have a shape which convergences toward a first position of the common electrode250, for example, an area of the common electrode250corresponding to the depression pattern152, due to a pretilt by side walls of the depression pattern152.

Referring toFIG. 3A, a gate metal layer (not shown) may be formed on the first base substrate110. The gate metal layer may be patterned through a photolithography process to form a gate pattern including the first and second gate lines GL1and GL2, the gate electrode GE and the storage line STL.

The gate insulation layer120may be disposed on the first base substrate110having the gate pattern formed thereon. The gate insulation layer120may include silicon oxide (SiOx) and/or silicon nitride (SiNx). In general, any suitable material may be used to form the gate insulation layer120.

The active pattern AP may include the semiconductor layer130aand the ohmic contact layer130b. The semiconductor layer130aand the ohmic contact layer130bmay sequentially be formed on the gate insulation layer120. The semiconductor layer130amay include amorphous silicon (a-Si), and the ohmic contact layer130bmay include N+ amorphous silicon doped with a high concentration of n-type dopants. In should be understood that various suitable materials may be used alone or in combination to form the semiconductor layer130aand/or the ohmic contact layer130b.

A data metal layer (not shown) may be formed on the active pattern AP. The data metal layer may be patterned through a photolithography process to form a source pattern including the first and second data lines DL1and DL2, the source electrode SE, the drain electrode DE, and the contact electrode CNT.

The passivation layer140and the domain-forming layer150may sequentially be formed on the source pattern. A material forming the passivation layer140may be, for example, silicon oxide (SiOx) and/or silicon nitride (SiNx). A material forming the domain-forming layer150may be, for example, an organic material such as a positive photoresist composition, a negative photoresist composition, and/or an inorganic material such as silicon oxide (SiOx), silicon nitride (SiNx). In should be understood that various suitable materials may be used alone or in combination to form the passivation layer140and the domain forming layer150.

Referring toFIG. 3B, the domain-forming layer150may be patterned to form the depression pattern152. The depression pattern152may be formed on the contact electrode CNT. The contact electrode CNT may overlap the storage line STL. The depression pattern152may be formed in a hole-shape exposing the passivation film140on the contact electrode CNT.

Then, the passivation film140exposed through the depression pattern152may be removed to form a passivation hole142. The passivation hole142may be formed on the contact electrode CNT. A portion of the contact electrode CNT may be exposed through the contact hole142and the depression pattern152.

Referring toFIG. 3C, a transmissive electrode layer (not shown) may be formed on the domain-forming layer150and in the depression pattern152. The transmissive electrode may be patterned to form the pixel electrode PE. The transmissive electrode layer may include indium tin oxide (ITO) and/or indium zinc oxide (IZO).

The first alignment layer AL1may be disposed on the pixel electrode PE. The first alignment layer AL1may include a vertical alignment material which may vertically align the liquid crystal molecules310.

Accordingly, the first substrate100including the gate insulation layer120, the active pattern AP, the source pattern, the passivation layer140, the depression pattern152, the pixel electrode PE, and the first alignment layer AL1may be manufactured.

FIG. 3Dis a cross-sectional view showing a method of manufacturing the second substrate ofFIG. 2B.

Referring toFIG. 3D, the black matrix pattern220may be formed on the second base substrate210. The black matrix pattern220may be formed by spraying an organic ink or patterning a metal layer through a photoetching process.

The first, second and third color filters232,234and236may be formed on the second base substrate210and the black matrix pattern220. For example, the first color filter232may be formed on the second base substrate210, the second color filer234may be formed on the first color filer232, and the third color filter234may be formed on the first and second color filters232and234. The first, second and third color filters232,234and236may be formed by patterning a color photoresist layer through a photoetching process or by spraying a color ink.

The overcoating layer240may be disposed on the black matrix pattern220and the first to third color filters232,234and236. An acrylate resin may be used to form the overcoating layer240.

A transmissive electrode layer (not shown) may be disposed on the overcoating layer240to form the common electrode250. In some cases, the common electrode250may cover the entire surface of the second base substrate210without patterning the transmissive electrode layer. The common electrode250may include indium tin oxide (ITO) and/or indium zinc oxide (IZO).

The second alignment layer AL2may be disposed on the common electrode250. In some cases, the second alignment layer AL2may cover the entire surface of the common electrode250.

Therefore, the second substrate200including the black matrix pattern220, the first to third color filters232,234and236, the overcoating layer240, the common electrode250, and the second alignment layer AL2may be manufactured.

FIG. 3Eis a cross-sectional view showing a step of forming the liquid crystal layer inFIG. 2B.

Referring toFIG. 3E, the first substrate100and the second substrate200may be assembled with each other. The liquid crystal molecules310and the RM monomer330may be disposed between the first substrate100and the second substrate200. In some cases, the liquid crystal molecules310and the RM monomer330may randomly be disposed between the first substrate100and the second substrate200.

A first voltage Vcom may then be applied to the common electrode250, and a second voltage Vdata that is different from the first voltage Vcom may be applied to the pixel electrode PE. The applied voltages (e.g., Vdata, Vcom) may be a positive voltage, a negative voltage, and/or a zero voltage (e.g., ground potential). By applying different voltages to the common electrode250and the pixel electrode PE, an electric field may be formed between the pixel electrode PE and the common electrode250. When the electric field is formed therebetween, a long axis of the liquid crystal molecules310may be perpendicular to the electric field direction.

In some cases, the first voltage Vcom may have a higher level than the second voltage Vdata. For example, the first voltage Vcom may be about 0 V, and the second voltage Vdata may be a negative value. The second voltage Vdata may be about −5 V.

When an electric field is formed between the first substrate100and the second substrate200thereby pretilting liquid crystal molecules310, light is irradiated into the first and second substrates100and200. The light may be, for example, ultraviolet (UV) light. The RM monomers330may react to the light and may be polymerized thus forming the RM curing material320between the liquid crystal molecules310. Accordingly, the liquid crystal layer300according to Example 1 may be formed.

A liquid crystal domain may be formed by the depression pattern152in the domain-forming layer150without separately forming a pattern on the common electrode250. Thus, an aperture ratio of the pixel area P and a viewing angle of the LCD may be enhanced. Moreover, since a separate pattern is not formed on the common electrode250, problems due to misalignment of the first and second substrates100and200may, in principle, no longer exist. Furthermore, a separate patterning process for patterning the common electrode250is omitted, so that a manufacturing process may be simplified. Therefore, production and display quality of a display device may be enhanced.

FIG. 4is a cross-sectional view of a display device according to some exemplary embodiments of the present invention.

A structure of the display device according to the illustrated embodiment shown inFIG. 4is substantially the same as the structure of the display device shown inFIG. 1. Thus, a plan view ofFIG. 4may be explained with reference toFIG. 1, and any repetitive detailed explanation may be hereinafter omitted.

Referring toFIG. 1andFIG. 4, a display device may include a first substrate100, a second substrate200, and a liquid crystal layer300.

The first substrate100may include a first base substrate110, a storage line STL, a gate insulation layer120, a first data line DL1, a second data line DL2, a passivation film140, a domain-forming layer150, a pixel electrode PE, and a first alignment layer AL1. The storage line STL may be formed on the first base substrate110. The gate insulation layer120may be disposed over the storage line STL. The first data line DL1and the second data line DL2may be formed on the gate insulation layer120. The passivation film140may be patterned and may expose a portion of the contact electrode CNT. The domain-forming layer150may be disposed on the passivation film140and the depression pattern152may be formed to expose a portion of the contact electrode CNT. The pixel electrode PE may be formed on the domain-forming layer150and may contact the contact electrode CNT through the depression pattern152. The first alignment layer AL1may cover the pixel electrode PE.

The domain-forming layer150may be formed on the passivation layer140to planarize the first substrate100. The domain-forming layer150may be formed in a pixel area P of the first base substrate110. The domain-forming layer150may include one or more color filters. For example, the domain-forming layer150may include a positive-type color photoresist and/or a negative-type color photoresist. For example, a first color filter layer CF1and a second color filter layer CF2may be respectively formed on areas adjacent to the pixel area P where the domain-forming layer150is formed. The domain-forming layer150may be formed using a different material than the materials used to form the first and second color filters CF1and CF2. The domain-forming layer150may provide a first color, the first color filter layer CF1may provide a second color different from the first color, and the second color filter layer CF2may provide a third color different from the first and second colors. In some cases, for example, the domain-forming layer150and the first and second color filters CF1and CF2may provide red, green, and blue colors.

The domain-forming layer150may include the depression pattern152, which may extend to an overlapping area with the storage line STL. The depression pattern152may form a liquid crystal domain of a pixel area P. Each of the first and second color filter layers CF1and CF2may include the depression pattern152. The depression pattern152may be substantially the same as the depression pattern described hereinabove with reference toFIG. 2AandFIG. 2B, thus any repetitive detailed explanation may be hereinafter omitted.

The domain-forming layer150may include a color layer (not shown) including color filters displaying different colors and a pattern layer (not shown) formed on the color layer. The color layer may include a first color filter, a second color filter, and a third color filter. The pattern layer may include the depression pattern152, which may form a liquid crystal domain in the pixel area P. The pattern layer may include an organic material and/or an inorganic material.

The second substrate200may include a common electrode250and a second alignment layer AL2, as described hereinabove with reference toFIG. 2AandFIG. 2B.

FIG. 5A,FIG. 5B, andFIG. 5Care cross-sectional views showing a method of manufacturing the display device ofFIG. 4.

FIG. 5AandFIG. 5Bare cross-sectional views illustrating a manufacturing process of the first substrate shown inFIG. 4. InFIG. 5A, the storage line STL, the gate insulation layer130, the first and second data lines DL1and DL2and the passivation film140may be formed in substantially the same manner as described with reference toFIG. 3A, and thus any repetitive detailed explanation may hereinafter be omitted.

Referring toFIG. 5A, a first color photoresist layer (not shown) may be formed on the passivation layer140from an organic material including a pigment displaying a first color. The first color photoresist layer may be patterned through a photolithography process to form the domain-forming layer150formed on the pixel area P. The domain-forming layer150may overlap portions of the first and second data lines DL1and DL2.

Referring toFIG. 4andFIG. 5B, a second color photoresist layer (not shown) may be formed on the domain-forming layer150and the passivation layer140, and may subsequently be patterned through a photolithography process to form the first color layer CF1. The first color layer CF1may be formed on a first side of the domain-forming layer150. That is, the first color layer CF1may be formed in an area adjacent to the pixel area P. The first color layer CF1may be a domain-forming layer of the first pixel area adjacent to the pixel area P.

A third color photoresist layer (not shown) may be disposed on the domain-forming layer150and the first color layer CF1. The third color photoresist layer may then be patterned through a photolithography process to form the second color layer CF2. The second color layer CF2may be a domain-forming layer of a second pixel area substantially adjacent to the pixel area P

Then, the depression pattern152may be formed on the domain-forming layer150. The depression pattern152may be formed on the contact electrode CNT. The depression pattern152may expose the passivation layer140on the contact electrode CNT. A plurality of depression patterns substantially identical to the depression pattern152may be formed in the first and second color layers CF1and CF2.

A portion of the passivation layer140exposed through the depression pattern152may be removed to form a passivation hole142to expose the contact electrode CNT. A transmissive electrode layer (not shown) may be formed on the passivation hole142. The transmissive electrode layer may then be patterned through a photolithography process to form the pixel electrode PE. The contact electrode CNT exposed through the depression pattern152and the passivation hole142may be in contact with the pixel electrode PE. The pixel electrode PE may cover the entire surface of the pixel area P.

The first alignment layer AL1may then be formed on the pixel electrode PE.

FIG. 5Cis a cross-sectional view illustrating a step of manufacturing the second substrate shown inFIG. 4.

Referring toFIG. 5C, a transmissive electrode layer (nor shown) may be formed on the second base substrate210, so that the common electrode250may be formed. In some cases, the common electrode250may be formed to cover the entire surface of the second baser substrate210without a process of patterning the transmissive electrode layer. The second alignment layer AL2may be formed on the common electrode250.

The first substrate100and the second substrate may then be assembled with each other, and a liquid crystal layer300may be formed between the first substrate100and the second substrate200. A process of forming the liquid crystal layer300may be substantially the same as the process of forming the liquid crystal layer as described hereinabove with reference toFIG. 3E, and any repetitive detailed explanation may hereinafter be omitted.

Thus, a display device according to Example 2 may be manufactured.

The depression pattern152may be formed without forming a separate pattern in the common electrode250, so that a liquid crystal domain may be formed. Thus, the aperture ratio of the pixel area P and the viewing angle of the display device may be enhanced. Moreover, since a separate pattern may not be formed on the common electrode250, misalignment of the first and second substrates100and200may, in principal, be removed. Furthermore, a separate patterning process for patterning the common electrode250may be omitted, so that a manufacturing process of the display device may be simplified. In addition, the domain-forming layer150may be formed using a color photoresist layer, so that a manufacturing process of the display device may be simplified.

FIG. 6is a plan view illustrating a display device according to some exemplary embodiments of the present invention.

FIG. 7is a cross-sectional view taken along a line III-III′ ofFIG. 6.

Referring toFIG. 6andFIG. 7, a display device according to some exemplary embodiments may include a first substrate100, a second substrate200, and a liquid crystal layer300.

The first substrate100may include a first base substrate110, first and second gate lines GL1and GL2, a storage line STL, a gate insulation layer120, first and second data lines DL1and DL2, a thin-film transistor (TFT) SW that may be a switching element, a passivation film140, a domain-forming layer150, a pixel electrode PE, and a first alignment layer AL1. The first substrate100may be substantially the same as the first substrate described with reference toFIG. 1,FIG. 2A, andFIG. 2Bexcept for the TFT SW and the domain-forming layer150. Any repetitive detailed explanation of the first substrate may hereinafter be omitted.

The TFT SW may include a gate electrode GE connected to the first gate line GL1, an active pattern (not shown) formed on the gate electrode GE, a source electrode SE connected to the first data line DL1, a drain electrode DE spaced apart from the source electrode SE1, and a contact electrode CNT connected to the drain electrode DE to contact the pixel electrode PE. The contact electrode CNT may be extended toward the storage line STL. The contact electrode CNT may be formed on a pixel area P of the first base substrate110and may not overlap with the storage line STL.

The domain-forming layer150may be formed on the first and second data lines DL1and DL2, the source electrode SE, and the drain electrode DE. The domain-forming layer150may include a depression pattern152which may be formed in an area corresponding to the storage line STL or may be formed in correspondence with patterns formed from an opaque metal except the storage line STL. The patterns formed from opaque metal except for the storage line STL may include, for example, the first and second gate lines GL1and GL2, and/or the first and second data lines DL1and DL2. The domain-forming layer150may be removed, at least partially, by a predetermined thickness, so that the depression pattern152may be formed. The depression pattern152may be formed in a hole-shape to expose the passivation layer140. The depression pattern152may form a liquid crystal domain of the pixel area P. The storage line STL and/or other patterns formed from an opaque metal formed below the depression pattern152may prevent light leakage generated by the depression pattern152from being generated.

InFIG. 6andFIG. 7, the domain-forming layer150may include one depression pattern152. In some cases, at least two depression patterns may be formed on the pixel area P. The number of the depression patterns152may determine the number of the liquid crystal domains.

The domain-forming layer150may further include a contact hole154exposing a portion of the contact electrode CNT. The pixel electrode PE may contact the contact electrode CNT through the contact hole154, so that the pixel electrode PE may be electrically connected to the TFT SW.

The second substrate200and the liquid crystal layer300may be substantially the same as the second substrate and the liquid crystal layer described with reference toFIG. 2AandFIG. 2B, and thus any repetitive detailed explanation may hereinafter be omitted.

Hereinafter, a method of manufacturing a display device according to some exemplary embodiments may be described with reference toFIG. 7andFIG. 8.

FIG. 8is a cross-sectional view showing a method of manufacturing the display device ofFIG. 7.

InFIG. 8, steps for respectively forming the storage line STL, the gate insulation layer120, the first and second data lines DL1and DL2, and the passivation layer140may be substantially the same as the steps explained with reference toFIG. 3A. Thus, any repetitive detailed explanation may be hereinafter omitted.

Referring toFIG. 8, the domain-forming layer150may be formed on the passivation layer140, and the domain-forming layer150may be patterned using a first mask A to form the depression pattern152.

The domain-forming layer150may be formed from a positive-type photoresist composition. The first mask ‘A’ may include a light-blocking portion1which may block light and a translucent portion2which may allow, at least partially, light to pass through. The first mask ‘A’ may allow approximately 0% to 30% of the light irradiated onto an upper portion of the first mask ‘A’ to pass through the translucent portion2.

When light is irradiated onto the upper portion of the first mask ‘A’ and the domain-forming layer150is developed, the domain-forming layer150corresponding to (i.e., aligned with) the light-blocking portion ‘1’ may remain on the passivation layer140and a portion of the domain-forming layer150corresponding to the translucent portion ‘2’ may be removed to form the depression pattern152.

The pixel electrode PE and the first alignment layer AL1may sequentially be formed on the domain-forming layer150comprising the depression pattern152. The pixel electrode PE and the first alignment layer AL1may be formed to cover an entire surface of the pixel area P. Thus, the first substrate100according to Example 3 may be manufactured.

Referring again toFIG. 7, the second substrate200may be manufactured, and the first substrate100and the second substrate200may be assembled with each other to produce the liquid crystal layer300, so that the display device according to some exemplary embodiments of the present invention may be manufactured.

InFIG. 7, a process manufacturing the second substrate200and a process manufacturing the liquid crystal layer300may substantially be the same as processes described with reference toFIG. 3AandFIG. 3E, respectively. Thus, any repetitive detained explanation may be hereinafter omitted.

As described above, a liquid crystal domain may be formed by forming the depression pattern152without forming a separate pattern on the common electrode250. Thus, the aperture ratio of the pixel area P and a viewing angle may be enhanced. Moreover, since a separate pattern may not be formed on the common electrode250, misalignment of the first and second substrates100and200may, in principle, be removed. Furthermore, a separate patterning process for patterning the common electrode250may be omitted, so that a manufacturing process of the display device may be simplified.

FIG. 9is a cross-sectional view of a display device according to some exemplary embodiments of the present invention.

A plan structure of the display device illustrated inFIG. 9may be substantially the same as a plan structure of the display device described with reference toFIG. 1. Thus a detailed description of the plan view ofFIG. 9may be omitted.

The display device ofFIG. 9is substantially the same as the display device ofFIG. 2Bexcept for a main spacer340and a sub-spacer350, and any repetitive detailed explanation may hereinafter be omitted.

Referring toFIG. 9, a display device may include a first substrate100, a second substrate200, and a liquid crystal layer300.

The first substrate100may include a storage line STL, a gate insulation layer120formed on the storage line STL, first and second data lines DL1and DL2formed on the gate insulation layer120, a contact electrode CNT of a TFT SW, a passivation layer140formed on the first and second data lines DL1and DL2, a domain-forming layer150including a depression pattern152for forming a liquid crystal domain of a pixel area P, a pixel electrode PE, and a first alignment layer AL1.

The second substrate200may include a black matrix pattern220formed on a second base substrate210, first, second and third color filters232,234and236, an overcoating layer240, a common electrode250, a second alignment layer AL2, a main spacer340, and a sub-spacer350.

The main spacer340may be formed on the second substrate200to maintain an interval between the first substrate100and the second substrate200. The height of the main spacer340may be substantially equal to a cell gap of the liquid crystal layer300. The main spacer340may be disposed on the first alignment layer AL1.

The sub-spacer350may be formed on the second substrate200. When the display device is suppressed by an external force, the sub-spacer350may buffer an interval between the first and second substrates100and200so that liquid crystal molecules310of the liquid crystal layer300may not be damaged. The height of the sub-spacer350may be less than the height of the main spacer340.

The main spacer340and/or the sub-spacer350may be formed on the second base substrate210corresponding to an area in which the depression pattern152is formed. A long axis of the liquid crystal molecules310may be arranged perpendicular to a surface of the main spacer340and/or the sub-spacer350, so that the liquid crystal molecules310situated in the depression pattern152may be pretilted. That is, the liquid crystal molecules310may be pretilted relative to the depression pattern152and one of the main spacer340and the sub-spacer350.

Hereinafter, a method of manufacturing a display device according to Example 4 may be described with reference to the followingFIGS. 9 and 10.

Referring toFIG. 9, the first substrate100may be manufactured. The first substrate100may be manufactured through processes that are substantially the same as the processes described with reference toFIG. 3A,FIG. 3B, andFIG. 3C.

The second substrate200may then be manufactured in substantially the same manner as the second substrate described with reference toFIG. 3Dexcept for manufacturing of the main spacer340and the sub-spacer350. Thus any repetitive detailed explanation may hereinafter be omitted.

FIG. 10is a cross-sectional view showing a method of manufacturing the display device ofFIG. 9.

Referring toFIG. 10, a photo layer (not shown) may be formed on the second alignment layer AL2. The second photo layer may be developed using a second mask B disposed on the photo layer to form the main spacer340and the sub-spacer350.

The photo layer may include a positive photoresist composition. The second mask B may include a light-blocking portion1, a translucent portion2, and a light-permeating portion3. The light-permeating portion3may be an area through which most of the light irradiated on an upper portion of the second mask B may passes.

Light may be irradiated on an upper portion of the second mask B and then the photo layer may be developed. A portion of the photo layer corresponding to the light-blocking portion1may remain to form the main spacer340. A portion of the photo layer corresponding to the translucent portion2may be removed, and a remainder of the photo layer may remain to form the sub-spacer350. A portion of the photo layer corresponding to the transparent portion3may be removed thereby exposing the second alignment layer AL2. Thus, the second substrate200according to some exemplary embodiments may be manufactured.

The liquid crystal layer300may be formed between the first substrate100and the second substrate200. Steps to form liquid crystal layer300may be substantially the same as the steps described with reference toFIG. 3E. Thus any repetitive detailed explanation may hereinafter be omitted.

Accordingly, the display device according to Example 4, which may include the first substrate100, the second substrate200, and the liquid crystal layer300, may be manufactured.

InFIG. 9andFIG. 10, the sub-spacer350may be formed relative to the depression pattern152. In some cases, the main spacer350may be formed relative to the depression pattern152, so that the liquid crystal molecules310may be pretilted.

Accordingly, in the display device described with reference toFIG. 9andFIG. 10, the aperture ratio of the pixel area P may be increased, and a viewing angle may be enhanced. Moreover, the reliability of a manufacturing process may be enhanced and a manufacturing process may be simplified.

FIG. 11is a plan view illustrating a display device according to Example 5 of the present invention.

FIG. 12is a cross-sectional view taken along a line IV-IV′ ofFIG. 11.

Referring toFIG. 11andFIG. 12, a display device may include a first substrate100, a second substrate200, and a liquid crystal layer300.

The first substrate100may include a first base substrate110, first and second gate lines GL1and GL2, a storage line STL, a gate insulation layer120, first and second data lines DL1and DL2, a TFT SW that may be a switching element, a passivation film140, a domain-forming layer150, a pixel electrode PE, a reflective electrode RFE, and a first alignment layer AL1. The first substrate100may be substantially the same as the first substrate described with reference toFIG. 1,FIG. 2A, andFIG. 2Bexcept for the TFT SW, the domain-forming layer150, and the reflective electrode RFE. Any repetitive detailed explanation may hereinafter be omitted.

The TFT SW may include a gate electrode GE connected to the first gate line GL1, an active pattern (not shown) formed on the gate electrode GE, a source electrode SE connected to the first data line DL1, a drain electrode DE spaced apart from the source electrode SE, a first contact pattern CT1connected to the drain electrode DE to contact the pixel electrode PE, and a second contact pattern CT2connected to the first contact pattern CT1extended in a pixel area P. The second contact pattern CT2may also contact the reflective electrode RFE.

The domain-forming layer150may cover the first and second data lines DL1and DL2. The domain-forming layer150may include a depression pattern152forming a liquid crystal domain of the pixel area P. The depression pattern152may include a first hole pattern H1exposing a portion of the first contact pattern CT1and a second hole pattern H2exposing a portion of the second contact pattern CT2. A first liquid crystal domain may be formed by the first hole pattern H1, and a second liquid crystal domain may be formed by the second hole pattern H2. That is, one pixel area P may be divided into two liquid crystal domains.

The pixel electrode PE may be formed on the domain-forming layer150, and, in some cases, may be formed in one area of the pixel area P. The pixel electrode PE may be formed using ITO and/or IZO. The reflective electrode RFE may be formed on the domain-forming layer150in another area of the pixel area P. The reflective electrode RFE may be formed, at least partially, of aluminum (Al). The first alignment layer AL1may be disposed on the pixel electrode PE and the reflective electrode RFE.

The second substrate200and the liquid crystal layer300are substantially the same as the second substrate and the liquid crystal layer described with reference toFIG. 1,FIG. 2A, andFIG. 2B, and thus any repetitive detailed explanation may hereinafter be omitted.

As illustrated inFIG. 11andFIG. 12, in some cases, the storage line STL may be situated between the first contact pattern CT1and the second contact pattern CT2. In some cases, the storage line STL may overlap with the first contact pattern CT1and/or the second contact pattern CT2.

In some cases, the depression pattern152may have two hole patterns H1and H2. In some cases, the depression pattern152may have a plurality of hole patterns to form a plurality of liquid crystal domains.

In some cases, the second hole pattern H2may be not formed in the depression pattern152.

In some cases, the pixel electrode PE and the reflective electrode RFE may be electrically connected to each other by a bridge. In some cases, to enhance side visibility (e.g., wide angle viewing), the pixel electrode PE and the reflective electrode RFE may be driven by using a first transistor connected to the pixel electrode PE and a second transistor connected to the reflective electrode RFE, or may be driven using a common swing method in which a common voltage applied to a common electrode may vary with respect to a data voltage.

FIG. 13AandFIG. 13Bare cross-sectional views showing a method of manufacturing the display device ofFIG. 12.

Referring toFIG. 12andFIG. 13A, a storage line STL may be formed on the first base substrate110, and the gate insulation layer120may be formed on the storage line STL. The first and second contact patterns CT1and CT2may be formed on the gate insulation layer120. The passivation layer140and the domain-forming layer150are sequentially formed on the first and second contact patterns CT1and CT2. The domain-forming layer150may be patterned to form the depression pattern152having the first and second hole patterns H1and H2.

Then, the passivation layer140exposed through the depression pattern152may be removed to expose the first and second contact electrodes CT1and CT2, respectively, thereby forming a transmissive electrode layer (not shown). The transmissive electrode layer may contact the first contact pattern CT1through the first hole pattern H1and the second contact pattern CT2through the second hole pattern H2. The transmissive electrode layer may then be patterned adjacent to the first hole pattern H1to form the pixel electrode PE contacting the first contact pattern CT1.

Referring toFIG. 13B, an opaque electrode layer (not shown) may be formed on the first base substrate110on which the pixel electrode PE is formed. The opaque electrode layer may be patterned adjacent to the second hole pattern H2to form the reflective electrode RFE contacting the second contact pattern CT2.

Then, the first alignment layer AL1may be formed on the pixel electrode PE and the reflective electrode RFE. The pixel electrode PE and the first alignment layer AL1may be formed without using a separate pattern to cover the entire surface of the pixel area P. Thus, the first substrate100according to some exemplary embodiments may be manufactured.

The second substrate200facing the first substrate100may be manufactured and the liquid crystal layer300may be formed between the first substrate100and the second substrate200, so that a display device according to Example 5 may be manufactured. A step forming the second substrate200and a step forming the liquid crystal layer300may be substantially the same as the steps explained inFIGS. 3D and 3E, respectively, and thus any repetitive detailed explanation may be hereinafter omitted.

FIG. 14is a cross-sectional view illustrating a transmissive-mode display device having a structure ofFIG. 11.

A plan structure of a transmissive-mode display device ofFIG. 14may be substantially the same as a plan structure ofFIG. 11. Moreover, the display device ofFIG. 14may be substantially the same as the display device ofFIG. 12except for a transmissive electrode TE, and thus any repetitive detailed explanation may hereinafter be omitted.

Referring toFIG. 14, a pixel electrode PE and a transmissive electrode TE may be formed on a domain-forming layer150. The transmissive electrode TE may contact a second contact pattern CT2through a second hole pattern H2. The transmissive electrode TE may include ITO and IZO, and may be identical to material(s) used to form the pixel electrode PE.

InFIG. 14, the pixel electrode PE and the transmissive electrode TE may be physically divided from each other. In some cases, the transmissive electrode TE may be connected to the pixel electrode PE.

According to the description of the display device in Example 5, an aperture ratio of the pixel area P may be increased, and a viewing angle may be enhanced. For example, a plurality of liquid crystal domains may be formed in one pixel area P, so that a viewing angle may be further enhanced. Moreover, the reliability of a manufacturing process may be enhanced and a manufacturing process may be simplified, so that the productivity of the display device may be enhanced.

FIG. 15is a plan view illustrating a display device according to some exemplary embodiments of the present invention.

FIG. 16is a cross-sectional view taken along a line V-V′ ofFIG. 15.

Referring toFIG. 15andFIG. 16, a display device may include a first substrate100, a second substrate200, and a liquid crystal layer300.

The first substrate100may include a first base substrate110, first and second gate lines GL1and GL2, a storage line STL, a bottom electrode BE, a gate insulation layer120, first and second data lines DL1and DL2, a TFT SW that may be a switching element, a domain-forming layer150, a pixel electrode PE, and a first alignment layer AL1. The first substrate100may be substantially the same as the first substrate described inFIG. 1,FIG. 2A, andFIG. 2Bexcept for the bottom electrode BE, and thus any repetitive detailed explanation may hereinafter be omitted.

The bottom electrode BE may be formed in a pixel area P to overlap the pixel electrode PE. The gate insulation layer120and the contact electrode CNT of the TFT SW may be formed between the bottom electrode BE and the pixel electrode PE. The bottom electrode BE may be formed on the storage line STL. The bottom electrode BE may directly contact the storage line STL and may be electrically connected to the storage line STL.

The bottom electrode BE and the pixel electrode PE may be charged at different voltages. As a result, an electric field may develop across the gate insulation layer120. Accordingly, the entire area of the pixel area P may be used as a storage capacitor Cst.

The second substrate200and the liquid crystal layer300are substantially the same as the second substrate and the liquid crystal layer described inFIG. 1,FIG. 2A, andFIG. 2B, and thus any repetitive detailed explanation may hereinafter be omitted.

FIG. 17A,FIG. 17B, andFIG. 17Care cross-sectional views showing a method of manufacturing the display device ofFIG. 16.

Referring toFIG. 16andFIG. 17, a gate metal layer (not shown) may be formed on the first base substrate110, and patterned to form a gate pattern including the first and second gate lines GL1and GL2, the gate electrode GE, and the storage line STL.

The gate pattern may include a transmissive electrode layer TEL formed on the first base substrate110. The transmissive electrode TEL may include a transparent conductive material. The transparent conductive material TEL may be indium tin oxide (ITO) and/or indium zinc oxide (IZO). In general, any suitable material(s) and combination thereof may be used for transparent conductive material.

Referring toFIG. 17B, the transmissive electrode layer TEL may be patterned to form the bottom electrode BE. The bottom electrode BE may directly contact the storage line STL.

Then, the gate insulation layer120may be formed on the bottom electrode BE.

Referring toFIG. 17C, an active pattern AP of the TFT SW may be formed on the gate insulation layer120, and a source pattern including the first and second data lines DL1and DL2, the source electrode SE, the drain electrode DE and the contact electrode CNT may be formed. The passivation film140may be formed on the source pattern, and the domain-forming layer150may be formed on the passivation film140.

A depression pattern152exposing a portion of the contact electrode CNT may be formed on the domain-forming layer150. The pixel electrode PE and the first alignment layer AL1may be sequentially formed on the depression pattern152. The pixel electrode PE and the first alignment layer AL1may be formed without a separate pattern covering, in some cases, the entire surface of the pixel area P. Thus, the first substrate100according to Example 6 may be manufactured.

The second substrate200facing the first substrate100may be manufactured and the liquid crystal layer300may be formed between the first and second substrates100and200, so that the display device according to some exemplary embodiments may be manufactured. A step for manufacturing the second substrate200and a step for manufacturing the liquid crystal layer300are substantially the same as the steps described inFIGS. 3D and 3E, respectively, and thus any repetitive detailed explanation may hereinafter be omitted.

According to the description of the display device in Example 6, an aperture ratio of the pixel area P may be increased, and a viewing angle may be enhanced. Moreover, the reliability of a manufacturing process may be enhanced and a manufacturing process may be simplified, so that the productivity of the display device may be enhanced.

FIG. 18is a plan view illustrating a display device according to some exemplary embodiments of the present invention.

FIG. 19Ais a cross-sectional view taken along a line VI-VI′ ofFIG. 18, andFIG. 19Bis a cross-sectional view taken along a line VII-VII′ ofFIG. 18.

Referring toFIG. 18,FIG. 19A, andFIG. 19B, a display device may include a first substrate100, a second substrate200, and a third substrate300.

The first substrate100may include a first base substrate110, first and second gate lines GL1and GL2, a storage line STL, a bottom electrode BE, a gate insulation layer120, first and second data lines DL1and DL2, a TFT SW that may be a switching element, a passivation film140, a domain-forming layer150, a pixel electrode PE, and a first alignment layer AL1.

The first and second gate lines GL1and GL2may be extended along a first direction D1on the first base substrate110. In some cases, the first and second data lines DL1and DL2may be arranged in a second direction D2that may be different from the first direction D1. The second direction D2may be substantially perpendicular to the first direction D1.

The storage line STL may be disposed between the first and second gate lines GL1and GL2to be extended along the first direction D1. The bottom electrode BE may directly contact a portion of the storage line STL. The bottom electrode BE may be formed in a pixel area P of the first base substrate110.

The gate insulation layer120may be formed on the first base substrate110to cover the first and second gate lines GL1and GL2, the storage line STL, and the bottom electrode BE.

The first and second data lines DL1and DL2may extend along the second direction D2on the gate insulation layer120. The first and second data lines DL1and DL2may cross the first and second gate lines GL1and GL2and the storage line STL.

The TFT SW may include a first gate electrode GE1, an active pattern AP, a is source electrode SE, a drain electrode DE, and a contact electrode CNT. The first gate electrode GE1may be connected to the first gate line GL1. The active pattern AP may be formed on the gate insulation layer120adjacent to the first gate electrode GE1. The source electrode SE may be connected to the first data line DL1to overlap the active pattern AP. The drain electrode DE may be spaced apart from the source electrode SE to overlap the active pattern AP. The contact electrode CNT may extend from the drain electrode DE to the pixel area P. The contact electrode CNT may extend from the drain electrode DE to overlap a portion of the storage line STL. The contact electrode CNT may have a large size and may be formed in an area adjacent to the first gate line GL1.

The domain-forming layer150may be formed on the passivation layer140. The domain-forming layer150may planarize the first substrate100. The domain-forming layer150may have a contact hole154exposing the contact electrode CNT. The pixel electrode PE formed on the domain-forming layer150may contact the contact electrode CNT through the contact hole154, so that the pixel electrode PE may be electrically connected to the TFT SW.

The pixel electrode PE may be formed on the domain-forming layer150of the pixel area P. The pixel electrode PE may include an optically transparent and electrically conductive material. The pixel electrode PE may have a dot-shaped opening pattern162formed in the pixel area P. The dot shape may be a circular shape, a polygonal shape, or a line shape. It should be understood that any suitable shape may be used in the opening pattern162. The liquid crystal molecules310of the liquid crystal layer300may converge towards a position in the second substrate200corresponding to an area in which the opening pattern162is formed. The liquid crystal molecules310may also be situated around the contact hole154and/or the pixel electrode PE. The opening pattern162may form a liquid crystal domain of the pixel area P. Moreover, a direction of the electric field in the liquid crystal layer300may be curved between an end portion of another pixel electrode adjacent to the pixel electrode PE and the common electrode250. Accordingly, the liquid crystal molecules310adjacent to the pixel electrodes PE may be diffused toward a different position of the common electrode250, so that a liquid crystal domain between adjacent pixel areas P may be divided.

The first alignment layer AL1may be formed, in some cases, on the entire surface of the first base substrate110including the pixel electrode PE.

The second substrate200may include a second base substrate210, a black matrix pattern220, first and second color filters232,234and236, an overcoating layer240, a common electrode250, and a second alignment layer AL2. The liquid crystal layer300may include liquid crystal molecules310, and an RM curing structure320. The second substrate200and the liquid crystal layer300are substantially the same as the second substrate and the liquid crystal described with reference toFIG. 2AandFIG. 2B, and the any repetitive detailed explanation may hereinafter be omitted.

Hereinafter, a method of manufacturing the first substrate100and the second substrate200according to some exemplary embodiments may be described with reference toFIG. 19AandFIG. 19B.

Referring toFIG. 19AandFIG. 19B, a gate metal layer (not shown) may be formed on the first base substrate110, and the gate metal layer may be patterned to form a gate pattern including the first and second gate lines GL1and GL2, the gate electrode GE, and the storage line STL.

A transmissive electrode layer (not shown) may be formed on the first base substrate110and the gate pattern. The transmissive electrode layer may be patterned to form the is bottom electrode, which may directly contact a first end portion of the storage line STL. In the pixel area P, the bottom electrode BE may directly contact the first base substrate110.

The active pattern AP may be formed on the first base substrate110on which the bottom electrode BE is formed. A source metal layer (not shown) may be formed on the first base substrate110including the active pattern AP. The source metal layer may be patterned to form a source pattern including the first and second data lines DL1and DL2, the source electrode SE, the drain electrode DE, and the contact electrode CNT.

The passivation layer140and the domain-forming layer150may be sequentially formed on the source pattern, and the pixel electrode PE and the first alignment layer AL1may be sequentially formed on the domain-forming layer150. Thus, the first substrate according to the some exemplary embodiments may be manufactured.

The second substrate200facing the first substrate100may be manufactured and the liquid crystal layer300may be formed between the first and second substrates100and200, so that the display device according to Example 7 may be manufactured. Steps for manufacturing the second substrate200may be substantially the same as the steps described with reference toFIG. 3D, and thus any repetitive detailed explanation may hereinafter be omitted. Hereinafter, a step for forming the liquid crystal layer300may be explained in detail with reference toFIG. 20.

FIG. 20is a flowchart showing a method of manufacturing the display device ofFIG. 19B.

Referring toFIG. 19BandFIG. 20, the first substrate100and the second substrate200may be assembled with each other, and a liquid crystal composition material may be disposed between the first and second substrates100and200. The liquid crystal composition material may include a plurality of liquid crystal molecules310and a plurality of RM monomers330(refer toFIG. 3E).

When the liquid crystal composition material is disposed between the first and second substrate100and200, a first voltage Vcom may be applied to the common electrode250(step S12), and a second voltage Vb1may be applied to the bottom electrode BE (step S14).

In some cases, the first voltage Vcom may be about 0 V. The second voltage Vb1may be higher than the first voltage Vcom. In some cases, the second voltage Vb1may range from about 7 V to about 16 V. The bottom electrode BE may receive the second voltage Vb1through the storage line STL. An electric field may be generated between the first and second substrates100and200due to the applied first voltage Vcom and second voltage Vb1. Due to the electric field, a long axis of the liquid crystal molecules310may be arranged in a perpendicular direction (e.g., perpendicular to the electric field).

Then, a third voltage Vdata may be applied to the pixel electrode PE (step S16). The third voltage Vdata may be higher than the first voltage Vcom and may be lower than the second voltage Vb1. The third voltage Vdata may be a positive polarity voltage or a negative polarity voltage. For example, the third voltage Vdata may be about 5 V.

When the liquid crystal molecules310are pretilted by using the first to third voltages Vcom, Vb1and Vdata, UV light is irradiated onto the first and second substrates100and200(step S50). The RM monomers330may be reactive to the UV light and may be polymerized. The polymerized RM curing material320(refer toFIG. 19B) may be formed, the liquid crystal molecules310may be fixed adjacent to the pixel electrode PE and/or the common electrode250, and the liquid crystal molecules310may be pretilted by the RM curing material320.

As described above, the second voltage Vb1may be higher than the third voltage Vdata applied to the pixel electrode PE and may be provided to the bottom electrode BE, so that the liquid crystal molecules310disposed in an area adjacent to the opening pattern162may be stably arranged using a strong electric field. Therefore, the liquid crystal layer300according to the Example 7 may be formed.

According to the description of the display device in Example 6, an aperture ratio of the pixel area P may be increased, and a viewing angle may be enhanced. Moreover, the reliability of a manufacturing process may be enhanced and a manufacturing process may be simplified, so that the productivity of the display device may be enhanced.

Hereinafter, another method of manufacturing a display device according the present embodiment may be explained in detail with reference toFIG. 19A,FIG. 19B, andFIG. 21. Steps for manufacturing the first and second substrates100and200according to the some exemplary embodiments are substantially the same as the steps for manufacturing the first and second substrates according to Example 7, respectively, and thus any repetitive detailed explanation may be hereinafter omitted.

Referring toFIG. 19A,FIG. 19B, andFIG. 21, the first substrate100and the second substrate200may be respectively manufactured and assembled with each other. A liquid crystal composition material may be disposed between the first and second substrates100and200. The liquid crystal composition material may include a plurality of liquid crystal molecules310, and a plurality of RM monomers330(refer toFIG. 3E).

FIG. 21is a flowchart showing a method of manufacturing a display device according to exemplary embodiments of the present invention.

Referring toFIG. 21, when the liquid crystal composition material is disposed between the first substrate100and the second substrate200, a first voltage Vcom may be applied to the common electrode250(step S22), and a second voltage Vb1may be applied to the bottom electrode BE (step S24). The second voltage Vb1may be higher than the first voltage Vcom. The second voltage Vb1may be provided to the bottom electrode BE through the storage line STL.

An electric field may be generated between the first and second substrates100and200due to the applied first voltage Vcom and second voltage Vb1. Due to the electric field, a long axis of the liquid crystal molecules310may be arranged in a perpendicular direction (e.g., perpendicular to the electric field).

A third voltage Vdata may then be applied to the pixel electrode PE (step S26). The third voltage Vdata may be higher than the first voltage Vcom and may be lower than the second voltage Vb1. Even though the third voltage Vdata may be applied to the pixel electrode PE, a strong electric field may form adjacent to the opening pattern162, so that an arrangement of liquid crystal molecules310disposed adjacent to the opening pattern162may not vary in comparison to an arrangement in which just the first voltage Vcom and the second voltage Vb1are applied. In some cases, the first, second, and third voltages Vcom, Vb1, and Vdata may employ a positive polarity voltage or a negative polarity voltage. In some cases, the first, second, and third voltages Vcom, Vb1, and Vdata may employ a DC voltage or an AC voltage.

A fourth voltage Vb2may be applied to the bottom electrode BE (step S28). The fourth voltage Vb2may be greater than the first, second, and third voltages Vcom, Vb1, and Vdata. The fourth voltage Vb2may be, for example, about 25 V. Thus, a strong electric field is formed between the common electrode250and the bottom electrode BE when the fourth voltage Vb2is applied, and a long axis of the liquid crystal molecules310may be perpendicular to the electric field direction due to the electric field formed between the common electrode250and the bottom electrode BE.

When the liquid crystal molecules310are pretilted using the first to fourth voltages Vcom, Vb1, Vdata, and Vb2, UV light may be irradiated onto the first and second substrates100and200(step S50). Due to the UV light, the RM monomers may react to light and may be polymerized. Thus, the polymerized RM curing material320(refer toFIG. 19B) may be formed, and the liquid crystal molecules310may be fixed adjacent to the pixel electrode PE and/or the common electrode250in a state in which the liquid crystal molecules310are pretilted by the RM curing material320.

As described above, the second voltage Vb1and the fourth voltage Vb2may be supplied to the bottom electrode BE so that the liquid crystal molecules310disposed in an area adjacent to the opening pattern163may be stably arranged in a strong electric field. The third voltage Vdata may be applied to the bottom electrode BE before the fourth voltage Vb2is applied to the bottom electrode BE, so that rapid movement of the liquid crystal molecules310may be prevented. Accordingly, the liquid crystal molecules310disposed in an area adjacent to the opening pattern163may be stably arranged in a strong electric field.

Although not shown inFIG. 21, irradiation of UV light onto the first substrate100and the second substrate200may be further performed before the fourth voltage Vb2is applied to the bottom electrode BE. UV light may be irradiated onto the first and second substrates100and200to partially react and polymerize the RM monomers330before the fourth voltage Vb2is applied thereto. The UV light may again be irradiated thereto after the fourth voltage Vb2is applied thereto, so that the RM monomers330may be fully polymerized.

According to the description of the display device in Example 7, an aperture ratio of the pixel area P may be increased, and a viewing angle may be enhanced. For example, liquid crystal molecules310of the liquid crystal layer300may be stably pretilted. Thus, the reliability of a manufacturing process may be enhanced and a manufacturing process may be simplified, so that the productivity of the display device may be enhanced.

FIG. 22is a cross-sectional view illustrating a display device according to some exemplary embodiments of the present invention.

InFIG. 22, the display device may be substantially the same as the display device described with reference toFIG. 18,FIG. 19A, andFIG. 19Bexcept for a depression pattern152in the domain-forming layer150, and thus any repetitive detailed explanation may hereinafter be omitted.

Referring toFIG. 22, a display device may include a first substrate100, a second substrate200, and a liquid crystal layer300.

The first substrate100may include a bottom electrode BE, a gate insulation layer120, first and second data lines DL1and DL2, a passivation film140, a domain-forming layer150, a pixel electrode PE, and a first alignment layer AL1.

The domain-forming layer150may include a depression pattern152having a dot shape formed in a pixel area P. The domain-forming layer150may be removed by a predetermined thickness, so that the depression pattern152may be formed. The depression pattern152may form a liquid crystal domain in the pixel area P.

The pixel electrode PE may include an opening pattern162having a dot shape. The opening pattern162may be formed in an area corresponding to the depression pattern152. The first alignment layer AL1may be formed on the pixel electrode PE and may contact the depression pattern152through the opening pattern162. The opening pattern162and the depression pattern152may form a liquid crystal domain on the pixel area P.

The second substrate200and the liquid crystal layer300may be substantially the same as the second substrate and the liquid crystal layer described inFIG. 18,FIG. 19A, andFIG. 19B, and thus any repetitive detailed explanation may hereinafter be omitted.

The display device according to Example 8 may be manufactured using the same manufacturing method described with reference to Example 7 except for forming the depression pattern152on the domain-forming layer150.

According to the description of the display device in Example 8, an aperture ratio of the pixel area P may be increased, and a viewing angle may be enhanced. Moreover, liquid crystal molecules310of the liquid crystal layer300may be stably pretilted. Thus, the reliability of a manufacturing process may be enhanced and a manufacturing process may be simplified, so that the productivity of the display device may be enhanced.

FIG. 23is a cross-sectional view illustrating a display device according to some exemplary embodiments of the present invention.

InFIG. 23, the display device may be substantially the same as the display device described with reference toFIG. 22except for a light-blocking pattern BL in a first substrate100. Any repetitive detailed explanation may hereinafter be omitted.

Referring toFIG. 23, a display device may include a first substrate100, a second substrate200, and a liquid crystal layer300.

The first substrate100may include a light-blocking pattern BL, a bottom electrode BE, a gate insulation layer120, first and second data lines DL1and DL2, a passivation film140, a domain-forming layer150, a pixel electrode PE, and a first alignment layer AL1.

The light-blocking pattern BL may be formed by patterning a gate metal layer that may be identical to a metal layer forming the first and second gate lines GL1and GL2. The light-blocking pattern BL may prevent light leakage, which may be due to an opening pattern162of the domain-forming layer150and an opening pattern162of the pixel electrode PE. The light-blocking pattern BL may be formed in an area corresponding to the depression pattern152and the opening pattern162.

The second substrate200and the liquid crystal layer300may be substantially the same as the second substrate and the liquid crystal layer described with reference toFIG. 18,FIG. 19A, andFIG. 19B, and thus any repetitive detailed explanation may hereinafter be omitted.

The display device according to Example 9 may be manufactured using the same manufacturing method as described for manufacturing the display device according to Example 7 except for formation of the depression pattern152on the domain-forming layer150.

InFIG. 23, the light-blocking pattern BL may be formed from the gate metal layer; however, the light-blocking pattern BL may be formed on the gate insulation layer120by patterning a source metal layer forming the first and second data lines DL1and DL2. In some cases, the light-blocking pattern BL may be formed from a layer identical to a black matrix pattern220formed on the second substrate200.

According to the description of the display device in Example 9, the aperture ratio of the pixel area P may be increased, and a viewing angle may be enhanced. For example, liquid crystal molecules310of the liquid crystal layer300may be stably pretilted. Thus, the reliability of a manufacturing process may be enhanced and a manufacturing process may be simplified, so that the productivity of the display device may be enhanced.

As described in detail, since a liquid crystal domain may be formed without a separate pattern on a common electrode, a display device having an enhanced aperture ratio and an enhanced viewing angle may be manufactured. Moreover, since a separate pattern is not formed on the common electrode, a misalignment cause of the first and second substrates may be removed in principle so that a manufacturing process of a display device may have enhanced reliability. Furthermore, since a separate patterning process for patterning the common electrode is omitted, a manufacturing process of the display device may be simplified. Therefore, the display device having enhanced productivity and display quality may be manufactured. The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of the present invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of the present invention. Accordingly, all such modifications are intended to be included within the scope of the present invention as defined in the claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Therefore, it is to be understood that the foregoing is illustrative of the present invention and is not to be construed as limited to the specific exemplary embodiments disclosed, and that modifications to the disclosed exemplary embodiments, as well as other exemplary embodiments, are intended to be included within the scope of the appended claims.