KR100357215B1 - Multi-domain liquid crystal display device - Google Patents

Abstract

The multi-domain liquid crystal display device of the present invention is formed on the first substrate and the second substrate facing each other, the liquid crystal layer formed between the first substrate and the second substrate, and vertically and horizontally formed on the first substrate to form a pixel region. A plurality of gate wirings and data wirings to be defined, a common auxiliary electrode formed on the same layer as the gate wiring and surrounding the pixel region, a pixel electrode integrally formed in the pixel region, and The storage electrode overlaps one gate line and is electrically connected to the pixel electrode in a region other than the pixel region.

Description

Multi-domain liquid crystal display device {MULTI-DOMAIN LIQUID CRYSTAL DISPLAY DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a multi-domain liquid crystal display device for distorting an electric field by forming a common auxiliary electrode to surround a pixel region in the same layer as a gate wiring. .

Recently, a liquid crystal display device for driving a liquid crystal by an auxiliary electrode electrically insulated from the pixel electrode without aligning the liquid crystal has been proposed. 1 is a cross-sectional view of a unit pixel of the above-described conventional liquid crystal display device.

The conventional liquid crystal display device includes a first substrate and a second substrate, a plurality of data wirings and gate wirings formed vertically and horizontally on the first substrate to divide the first substrate into a plurality of pixel regions, and the pixel regions on the first substrate, respectively. A thin film transistor (TFT) formed at the gate electrode, a gate insulating film, a semiconductor layer, an ohmic contact layer, and a source / drain electrode, and a protective film formed over the entire first substrate. ), A pixel electrode 13 formed to be connected to the drain electrode on the passivation layer 37, and an auxiliary electrode 21 formed to overlap a portion of the pixel electrode 13 on the gate insulating layer.

The light blocking layer 25 for blocking light leaking from the gate wiring, the data wiring, and the thin film transistor on the second substrate, the color filter layer 23 formed on the light blocking layer 25, and A common electrode 17 formed on one color filter layer 23 and a liquid crystal layer formed between the first substrate and the second substrate.

The auxiliary electrode 21 formed around the pixel electrode 13 and the open region 27 of the common electrode 17 distort the electric field applied to the liquid crystal layer, thereby driving various liquid crystal molecules in the unit pixel. This means that when a voltage is applied to the liquid crystal display, the dielectric energy due to the distorted electric field places the liquid crystal director in a desired direction.

However, the liquid crystal display device requires an open area 27 in the common electrode 17 in order to obtain a multi-domain effect. To this end, a process of patterning the common electrode 17 in the manufacturing process of the liquid crystal display device is added. do.

In addition, if the open area is not present or the width thereof is small, the degree of electric field distortion required for domain division is weak, and thus, the time for reaching the stable state of the liquid crystal director is relatively long.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the prior art, and forms a common auxiliary electrode so as to surround a pixel region on the same layer as a gate wiring, and forms a storage electrode so as to overlap the gate wiring. An object of the present invention is to provide a multi-domain liquid crystal display device in which an electrode is electrically connected to a pixel electrode in a region other than the above-described pixel region, thereby improving aperture ratio and implementing a multi-domain effect.

The multi-domain liquid crystal display device of the present invention corresponds to the invention described in the patent application No. 1999-05587 filed by the applicant of the present application, and the storage electrode is formed so as to be electrically connected to the pixel electrode in a region other than the pixel region. As an improved invention, it shares with the technical idea.

In order to achieve the above object, the multi-domain liquid crystal display device according to the present invention, the opposing first substrate and second substrate, the liquid crystal layer formed between the first substrate and the second substrate, and the first A plurality of gate wirings and data wirings formed vertically and horizontally on a substrate to define a pixel region, a common auxiliary electrode formed on the same layer as the gate wiring and surrounding the pixel region, and the first substrate as a whole A gate insulating film formed over the gate insulating film, a storage electrode formed to overlap the gate wiring on the gate insulating film, a protective film formed over the entire first substrate on the gate insulating film, and integrally formed in the pixel region. A pixel electrode, a light shielding layer formed on said second substrate, a color filter layer formed on said light shielding layer, a common electrode formed on said color filter layer, and It made of an orientation film formed on at least one substrate of the aforementioned first substrate and second substrate, in a region other than the above-mentioned storage electrode above the pixel region being electrically connected to the pixel electrode and the.

The multi-domain liquid crystal display device further includes a storage electrode connected to the pixel electrode under the passivation layer and overlapping the common auxiliary electrode.

The liquid crystal described above is a liquid crystal having positive or negative dielectric anisotropy, and the liquid crystal layer contains a chiral dopant.

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

2A, 2B, and 2C, 2D, 2E, 2F, and 2G are plan and cross-sectional views of a multi-domain liquid crystal display device according to a first embodiment of the present invention.

3A, 3B, and 3C, 3D, 3E, 3F, 3G, and 3H are plan and cross-sectional views of a multi-domain liquid crystal display device according to a second embodiment of the present invention.

4A and 4B are a plan view and a sectional view of a multi-domain liquid crystal display device according to a third embodiment of the present invention.

5A, 5B, and 5C and 5D are plan and cross-sectional views of a multi-domain liquid crystal display device according to a fourth embodiment of the present invention.

6A to 6G illustrate various electric field induction windows or dielectric structures of a multi-domain liquid crystal display device according to an exemplary embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

1: gate wiring 3: data wiring

5 semiconductor layer 7 source electrode

9 drain electrode 11 gate electrode

13 pixel electrode 15 common auxiliary electrode

17: common electrode 21: auxiliary electrode

23: color filter layer 25: light shielding layer

27: open area 29: retardation film

31: first substrate 33: second substrate

35 gate insulating film 37 protective film

39: contact hole 43: storage electrode

51: electric field induction window (hole or slit) 53: dielectric structure

Hereinafter, a multi-domain liquid crystal display device according to the present invention will be described in detail with reference to the drawings.

2A and 2B are plan views of a multi-domain liquid crystal display device according to a first exemplary embodiment of the present invention, and FIG. 2C is a cross-sectional view taken along the line II ′ of FIG. 2A, and FIGS. 2D, 2E, 2F, and 2G are the above. It is sectional drawing along the II-II 'line | wire of FIG. 2A.

As shown in the above drawings, the multi-domain liquid crystal display device of the present invention is formed vertically and horizontally on the first substrate 31 and the second substrate 33 and the above-described first substrate to form a plurality of pixels. A plurality of data wirings 3 and gate wirings 1 divided into regions, a common auxiliary electrode 15 formed on the same layer as the gate wirings to distort an electric field, and a pixel region on the first substrate, respectively; A thin film transistor including a gate electrode 11, a gate insulating film 35, a semiconductor layer 5, an ohmic contact layer, and source / drain electrodes 7 and 9, and a protective film 37 formed over the entire first substrate. And a pixel electrode 13 connected to the drain electrode 9 on the passivation layer.

On the second substrate 33, the light blocking layer 25 for blocking light leaking from the gate wiring 1, the data wiring 3, and the thin film transistor, and the light blocking layer 25 above. The formed color filter layer 23, the common electrode 17 formed on the color filter layer, and a liquid crystal layer formed between the first substrate and the second substrate.

In order to manufacture a multi-domain liquid crystal display device having the above structure, first, a gate electrode 11, a gate insulating film 35, a semiconductor layer, an ohmic contact layer, and a source / drain electrode 7 are respectively formed in each pixel area of the first substrate. A thin film transistor consisting of 9) is formed. At this time, a plurality of gate wirings 1 and data wirings 3 are formed which divide the first substrate into a plurality of pixel regions.

The gate electrode 11 and the gate wiring 1 are formed by stacking a metal made of Al, Mo, Cr, Ta, Al alloy, or a double layer thereof by a sputtering method and then patterning the same. At the same time, the common auxiliary electrode 15 is formed to surround the pixel region. The gate insulating film 35 is formed thereon by laminating SiN _X or SiO _X by PECVD. Subsequently, the semiconductor layer and the ohmic contact layer are formed by laminating a-Si and n ⁺ a-Si, respectively, by PECVD (Plasma Enhanced Chemical Vapor Deposition). Further, the gate insulating film 35, a-Si, and n ⁺ a-Si can be patterned by continuous deposition by PECVD.

Then, metals such as Al, Mo, Cr, Ta, or Al alloys are stacked and patterned by sputtering to form data wirings 3 and source / drain electrodes 7 and 9. At this time, the storage electrode 43 is formed at the same time so as to overlap the gate wiring 1 and / or the common auxiliary electrode 15, and the storage electrode 43 is the gate wiring 1 and / or It serves as a common auxiliary electrode 15 and a storage capacitor.

Subsequently, the protective film 37 is formed of a material such as BCB (BenzoCycloButene), an acrylic resin, a polyimide compound, SiN _X or SiO _X and the like, and the ITO (indium) is formed over the first substrate 31. Tin oxide) is stacked by the sputtering method and then patterned to form the pixel electrode 13.

At this time, the pixel electrode 13 is formed with an extension portion protruding so as to partially overlap with the storage electrode 43, and by removing the protective film under the extension portion to form a contact hole 39 electrically. Connected. In addition, it is connected to the drain electrode 9 through the contact hole 39 on the drain electrode 9 in the same manner.

When the common auxiliary electrode 15 is formed of the same material as the gate wiring 1, the common auxiliary electrode 15 is formed on the same layer as the gate wiring 1 with the same mask to form the same layer as the gate electrode 1. It can be electrically connected and made up of different metals using additional masks, or from different double layers.

The light blocking layer 25 is formed on the second substrate 33, and the color filter layer 23 is formed such that R, G, and B (red, green, blue) elements are repeated for each pixel. The photosensitive material is laminated on the color filter layer 23 and then patterned by photolithography to form the dielectric structure 53 in various shapes.

Subsequently, the common electrode 17 is formed of a transparent electrode such as ITO or the like as the pixel electrode 13, and a liquid crystal is injected between the first substrate 31 and the second substrate 33 by the liquid crystal. Complete the display element. The liquid crystal constituting the liquid crystal layer may use a liquid crystal having positive or negative dielectric anisotropy, and may also include a chiral dopant.

The material constituting the dielectric structure 53 preferably has a dielectric constant equal to or less than the dielectric constant of the liquid crystal layer, preferably 3 or less, and a material such as acrylic (photoacrylate) or BCB (BenzoCycloButene). Can be mentioned.

In the method of applying the voltage V _com to the common auxiliary electrode 15, the Ag substrate is formed on each corner of the driving region of the liquid crystal display device on the first substrate 31. An electric field is applied to drive the liquid crystal by the vertical potential difference. The Ag-Dotting part of each corner and the common auxiliary electrode 15 are connected to apply a voltage V _com . This process is performed simultaneously with forming the common auxiliary electrode 15.

In addition, the multi-domain liquid crystal display device of the present invention draws a polymer on at least one of the first substrate 31 or the second substrate 33 to form a retardation film 29.

The retardation film 29 is a negative uniaxial film, which is formed of a uniaxial material having one optical axis, and serves to compensate for a user's feeling in a direction perpendicular to the substrate and a direction depending on a viewing angle change. Accordingly, the viewing angle in the left and right directions can be more effectively compensated by widening the region without gray inversion, increasing the contrast ratio in the oblique direction, and forming one pixel in a multi-domain.

In the multi-domain liquid crystal display device of the present invention, in addition to the negative uniaxial film described above, a negative biaxial film may be formed as a retardation film, and a negative biaxial film composed of a biaxial material having two optical axes. Compared to the uniaxial film described above, a wide viewing angle characteristic can be obtained.

After attaching the retardation film, a polarizer (not shown) is attached to both substrates, and the polarizer may be formed integrally with the retardation film.

In the multi-domain liquid crystal display device illustrated in FIG. 2, the pixel electrode 13 overlaps the common auxiliary electrode 15, and the light blocking layer 25 also overlaps the common auxiliary electrode, so that the aperture ratio is high. Reference numeral 43 overlaps the gate wiring 1 and the common auxiliary electrode 15 to form a storage capacitor.

2D and 2E illustrate embodiments in which the dielectric structure 53 is formed on the common electrode 17, and FIGS. 2F and 2G illustrate embodiments in which the electric field induction window 51 is formed in the common electrode 17. to be. 2D and 2F show an embodiment in which the protective film 37 is formed of a material such as SiN _X or SiO _X. FIGS. 2E and 2G illustrate BCB (BenzoCycloButene), acrylic resin, or polyimide. ) Is an embodiment formed of a compound and planarized.

3A and 3B are plan views of a multi-domain liquid crystal display device according to a second exemplary embodiment of the present invention, and FIGS. 3C and 3D are cross-sectional views taken along line III-III 'of FIG. 3B, and FIGS. 3E, 3F, 3G, and 3H are FIGS. It is sectional drawing along the IV-IV 'line | wire of FIG. 3A.

In the above drawings, the pixel electrode 13 does not overlap the common auxiliary electrode 15, and thus, the light blocking layer 25 is formed to overlap the pixel electrode 13. In this case, the gate insulating layer and the protective layer formed on the common auxiliary electrode 15 are removed to strengthen the electric field of the common auxiliary electrode 15 applied to the pixel electrode 13, and the common auxiliary electrode 15 is removed. And the pixel electrode 13 are obtained in the same plane. 3C is a structure in which a gate insulating layer and a protective layer are removed to expose a part of the common auxiliary electrode, and FIG. 3D is a structure in which the common auxiliary electrode is completely exposed.

The storage electrode 43 overlaps the gate wiring 1 and the common auxiliary electrode 15 to form a storage capacitor.

3E and 3F illustrate embodiments in which the dielectric structure 53 is formed on the common electrode 17, and FIGS. 3G and 3H illustrate embodiments in which the electric field induction window 51 is formed in the common electrode 17. to be. 3E and 3G illustrate embodiments in which the protective layer 37 is formed of a material such as SiN _X or SiO _X. FIGS. 3F and 3H illustrate BCB (BenzoCycloButene), acrylic resin, or polyimide. ) Is an embodiment formed of a compound and planarized.

4A is a plan view of a multi-domain liquid crystal display device according to a third exemplary embodiment of the present invention, and FIG. 4B is a cross-sectional view taken along the line VV ′ of FIG. 4A.

The liquid crystal display device is formed so that the upper and lower pairs of pixels share the common auxiliary electrode 15, and the storage electrodes 43 of the upper and lower pixels are formed on the common auxiliary electrode 15. As a structure, the aperture ratio can be greatly improved than the liquid crystal display device shown in FIG.

In addition, the pixel electrode 13 is formed to overlap the common auxiliary electrode 15, the light blocking layer 25 also overlaps with the common auxiliary electrode, and the storage electrode 43 is the common auxiliary electrode 15 and the storage capacitor. To form. In the third embodiment, the dielectric structure 53 may be formed on the common electrode 17, or the electric field induction window 51 may be formed in the common electrode 17.

5A and 5B are plan views of a multi-domain liquid crystal display device according to a fourth exemplary embodiment of the present invention, and FIGS. 5C and 5D are cross-sectional views taken along line VI-VI 'of FIG. 5B.

The liquid crystal display device is configured in the same manner except for the following parts.

The pixel electrode 13 does not overlap the common auxiliary electrode 15, and thus, the light blocking layer 25 is formed to overlap the pixel electrode 13. In this case, the gate insulating layer and the protective layer formed on the common auxiliary electrode 15 are removed to strengthen the electric field of the common auxiliary electrode 15 applied to the pixel electrode 13, and the common auxiliary electrode 15 is removed. And the pixel electrode 13 are obtained in the same plane. 5C illustrates a structure in which a gate insulating layer and a protective layer are removed to expose a portion of the common auxiliary electrode, and FIG. 5D is a structure in which the common auxiliary electrode is completely exposed.

Embodiments of the multi-domain liquid crystal display device of the present invention are a high-throughput thin film transistor (L-lined Thin Film Transistor) structure, the L-shaped TFT is formed by forming the TFT in the L-shape on the gate wiring (1), Compared with the conventional liquid crystal display device, the aperture ratio is improved, and parasitic capacitors generated between the gate wiring 1 and the drain electrode 9 can be reduced.

6A-6G illustrate various field induction windows 51 or dielectric structures 53 in accordance with one embodiment of the present invention. In the multi-domain liquid crystal display device of the present invention, a dielectric structure 53 is formed on the pixel electrode 13 and / or the common electrode 17, or the pixel electrode 13, the passivation layer 37, and the gate are formed. Electric field distortion is caused by patterning the insulating film 35, the color filter layer 23, the overcoat layer and / or the common electrode 17 and forming an electric field induction window 51 such as a hole or a slit therein. Implement effects and multidomains.

The electric field induction window 51 or the dielectric structure 53 has the effect of dividing the pattern into two domains by patterning the pattern horizontally, vertically, and diagonally, or ×, +, or ◇ shape, comb shape, The effect of dividing the double-wire (Fig. 6G) shape and the × and + -shape at the same time to divide into 4 domains and multi-domains, and formed on at least one of the first and second substrates, or both It is also possible to apply them independently or in combination.

In addition, the multi-domain liquid crystal display device of the present invention forms an alignment film (not shown) over the entirety of the first substrate and / or the second substrate. In this case, a material such as polyamide or polyimide compound, PVA (polyvinylalcohol), polyamic acid or SiO ₂ may be used as the alignment material constituting the alignment layer. In the case of determining the orientation direction by use, any material suitable for other rubbing treatments can be applied.

In addition, the alignment layer may be formed of a photoreactive material, that is, a material such as PVCN (polyvinylcinnamate), PSCN (polysiloxanecinnamate), or CelCN (cellulosecinnamate) -based compound to form a photoalignment film, and other optical alignment treatment Any material suitable for is applicable. The photoalignment film is irradiated with light at least once to determine the pretilt angle and alignment direction or pretilt direction of the liquid crystal molecules at the same time, and thereby Secure the orientation stability. As for the light used for the optical alignment, light in the ultraviolet region is suitable, and any light among non-polarized light, linearly polarized light, and partially polarized light may be used.

The rubbing method or the photo-alignment method may be applied to only one of the first substrates or the second substrates, or may be treated on both substrates, or may be subjected to different alignment treatments on both substrates, or only an alignment film is formed and the alignment treatment is performed. It is also possible not to.

In addition, by performing the above-described alignment process, a multi-domain liquid crystal display device divided into at least two regions can be formed so that the liquid crystal molecules of the liquid crystal layer can be differently aligned on each region. That is, the multi-domain effect is realized by dividing each pixel into four regions, such as + or × characters, or by dividing them into horizontal, vertical, or diagonal lines, and by forming different alignment processes or orientation directions in each region and each substrate. do. At least one of the divided regions may be a non-oriented region, and the entire region may be a non-oriented region.

In the multi-domain liquid crystal display device of the present invention, the common auxiliary electrode is formed on the same layer as the gate wiring, and the storage electrode is formed to overlap with the gate wiring, and the storage electrode is the pixel region. It is formed to be electrically connected to the pixel electrode in other areas, thereby inducing electric field distortion, thereby maximizing the high opening ratio and the multi-domain effect.

In addition, since the common auxiliary electrode is on the same layer as the gate wiring, the short between the pixel electrode and the common auxiliary electrode can be prevented and the yield can be improved.

Claims (31)

Opposing first and second substrates, A liquid crystal layer formed between the first substrate and the second substrate; A plurality of gate wirings and data wirings formed vertically and horizontally on the first substrate to define pixel regions; A common auxiliary electrode formed on the same layer as the gate wiring and surrounding the pixel area; A gate insulating film formed over the entire first substrate; A storage electrode formed on the gate insulating layer to overlap the gate wiring; A protective film formed over the first substrate on the gate insulating film; A pixel electrode integrally formed in the pixel region; A light blocking layer formed on the second substrate; A color filter layer formed on the light shielding layer; A common electrode formed on the color filter layer; In the multi-domain liquid crystal display device comprising an alignment film formed on at least one of the first substrate and the second substrate, And the storage electrode is electrically connected to the pixel electrode in a region other than the pixel region. The multi-domain liquid crystal display device of claim 1, further comprising a storage electrode connected to the pixel electrode under the passivation layer and formed to overlap the common auxiliary electrode. The multi-domain liquid crystal display device of claim 1, wherein the pixel electrode is formed to overlap the common auxiliary electrode. The multi-domain liquid crystal display device of claim 3, wherein the light blocking layer is formed to overlap the common auxiliary electrode. The multi-domain liquid crystal display of claim 1, wherein the pixel electrode is formed so as not to overlap with the common auxiliary electrode. 6. The multi-domain liquid crystal display device of claim 5, wherein the light shielding layer is formed to overlap the pixel electrode. The multi-domain liquid crystal display device according to claim 1, wherein the gate insulating film and the protective film are formed in a region other than the common auxiliary electrode. The multi-domain liquid crystal display device of claim 1, wherein the common auxiliary electrode is electrically connected to the common electrode. The multi-domain liquid crystal display device of claim 1, further comprising an electric field distortion dielectric structure on the pixel electrode. The multi-domain liquid crystal display device of claim 1, further comprising a dielectric structure for electric field distortion on the common electrode. The multi-domain liquid crystal display device according to claim 1, wherein the pixel electrode has an electric field induction window therein. The multi-domain liquid crystal display device according to claim 1, wherein the protective film has an electric field induction window therein. The multi-domain liquid crystal display device according to claim 1, wherein the gate insulating film has an electric field induction window therein. The multi-domain liquid crystal display device according to claim 1, wherein the common electrode has an electric field induction window therein. The multi-domain liquid crystal display device according to claim 1, wherein the color filter layer has an electric field induction window on its surface. The multi-domain liquid crystal display device according to claim 1, further comprising an overcoat layer on the color filter layer. 17. The multi-domain liquid crystal display device according to claim 16, wherein the overcoat layer has an electric field induction window therein. The multi-domain liquid crystal display device according to claim 1, wherein the material constituting the protective film is selected from the group consisting of BCB (BenzoCycloButene), acrylic resin, and polyimide compound. The multi-domain liquid crystal display device according to claim 1, wherein the material constituting the protective film is selected from the group consisting of SiN _X and SiO _X. The material constituting the common auxiliary electrode is selected from the group consisting of indium tin oxide (ITO), Al, Mo, Cr, Ta, Ti, Al alloy, and a double layer thereof. Multi-domain liquid crystal display device. The multi-domain liquid crystal display of claim 1, wherein the material constituting the common electrode is made of indium tin oxide (ITO). The multi-domain liquid crystal display device according to claim 1, wherein the pixel region is divided into at least two regions so that the liquid crystal molecules of the liquid crystal layer exhibit different driving characteristics on each region. The multi-domain liquid crystal display device according to claim 1, wherein the alignment film is divided into at least two regions so that the liquid crystal molecules of the liquid crystal layer exhibit different alignment characteristics on each region. 24. The multi-domain liquid crystal display device according to claim 23, wherein at least one of the regions of the alignment film is subjected to an alignment process. The multi-domain liquid crystal display device according to claim 23, wherein all of the regions of the alignment film are not aligned. The multi-domain liquid crystal display device according to claim 1, wherein the liquid crystal constituting the liquid crystal layer is a liquid crystal having positive or negative dielectric anisotropy. The multi-domain liquid crystal display device of claim 1, further comprising: forming a negative uniaxial film on at least one of the first and second substrates. The multi-domain liquid crystal display device of claim 1, further comprising: forming a negative biaxial film on at least one of the first and second substrates. The multi-domain liquid crystal display device according to claim 1, wherein the liquid crystal layer comprises a chiral dopant. Opposing first and second substrates, A liquid crystal layer formed between the first substrate and the second substrate; A plurality of gate wirings and data wirings formed vertically and horizontally on the first substrate to define pixel regions; A common auxiliary electrode formed on the same layer as the gate wiring and surrounding the pixel area; A pixel electrode integrally formed in the pixel region, and And a storage electrode overlapping the gate wiring and electrically connected to the pixel electrode in a region other than the pixel region. Opposing first and second substrates, A liquid crystal layer formed between the first substrate and the second substrate; A plurality of gate wirings and data wirings formed vertically and horizontally on the first substrate to define pixel regions; An L-lined thin film transistor formed at an intersection point of the gate line and the data line; A common auxiliary electrode formed on the same layer as the gate wiring and surrounding the pixel area; A gate insulating film formed over the entire first substrate; A protective film formed over the first substrate on the gate insulating film; A pixel electrode integrally formed in the pixel region; A storage electrode overlapping the gate wiring and formed to be electrically connected to the pixel electrode in a region other than the pixel region; A light blocking layer formed on the second substrate; A color filter layer formed on the light shielding layer; A common electrode formed on the color filter layer; A multi-domain liquid crystal display device comprising an alignment film formed on at least one of the first substrate and the second substrate.