KR20120034517A - Electrophoretic display device and method of fabricating thereof - Google Patents

Abstract

PURPOSE: An electrophoretic display device and a manufacturing method thereof are provided to prevent misalignment between an electrophoretic layer and a first substrate, thereby reducing manufacturing costs and simplifying manufacturing processes. CONSTITUTION: A thin film transistor is formed on each pixel of a first substrate. A protective layer is formed on the first substrate on which the thin film transistor is formed. A pixel electrode is formed on an image display area on the protective layer. A partition wall(180) is formed on a non image display area of the protective layer. An electrophoretic layer(160) is formed on an image display area and contacts the pixel electrode. A first obstacle(190a) is formed along with an external outline of the first substrate. At least one second obstacle and third obstacle(190b,190c) form a space(193) between the first, second, and third obstacles. A sealing material(194) is coated on the first obstacle to seal the first substrate and a second substrate.

Description

Electrophoretic display device and its manufacturing method {ELECTROPHORETIC DISPLAY DEVICE AND METHOD OF FABRICATING THEREOF}

The present invention relates to an electrophoretic display device and a method of manufacturing the same.

In general, an electrophoretic display device is an image display device using a phenomenon in which colloidal particles move to either polarity when a pair of electrodes to which voltage is applied is immersed in a colloidal solution. A wide viewing angle, high reflectance, and low consumption without using a backlight Since it has characteristics, such as an electric power, it is attracting attention as an electronic device, such as an electric paper.

The electrophoretic display device has a structure in which an electrophoretic layer is interposed between two substrates, one of the two substrates is made of a transparent substrate, and the other is composed of an array substrate on which a driving element is formed, thereby reflecting input light. The image can be displayed in the reflective mode.

1 is a view showing the structure of a conventional electrophoretic display device (1). As shown in FIG. 1, the electrophoretic display device 1 includes a first substrate 20 and a second substrate 40, a thin film transistor and a pixel electrode 18 formed on the first substrate 20, The common electrode 42 formed on the second substrate 40, the electrophoretic layer 60 formed between the first substrate 20 and the second substrate 40, the electrophoretic layer 60 and the pixel. It consists of an adhesive layer 56 formed between the electrodes 18.

The thin film transistor includes a gate electrode 11 formed on the first substrate 2, a gate insulating layer 22 formed over the entire first substrate 20 on which the gate electrode 11 is formed, and the gate insulating layer ( And a source electrode 15 and a drain electrode 16 formed on the semiconductor layer 13. The passivation layer 24 is formed on the source electrode 15 and the drain electrode 16 of the thin film transistor.

The pixel electrode 18 for applying a signal to the electrophoretic layer 60 is formed on the passivation layer 24. In this case, a contact hole 28 is formed in the passivation layer 24 so that the pixel electrode 18 on the passivation layer 24 is connected to the drain electrode 16 of the thin film transistor through the contact hole.

In addition, a common electrode 42 is formed on the second substrate 40, and an electrophoretic layer 60 is formed on the common electrode 42. At this time, the adhesive layer 56 is formed on the electrophoretic layer 60 to bond the second substrate 40 including the electrophoretic layer 60 to the first substrate 20. The electrophoretic layer 60 includes a capsule 70 filled with white particles 74 and black particles 76 having electrophoretic properties therein. When a signal is applied to the pixel electrode 18, an electric field is generated between the common electrode 42 and the pixel electrode 18, and the white particles 74 and the black particles inside the capsule 70 are generated by the electric field. 76 moves to implement the image.

For example, when a negative voltage is applied to the pixel electrode 18, the common electrode 42 of the second substrate 40 has a relatively positive potential and thus has a white particle having a positive charge. 74 moves toward the first substrate 20, and the black particles 76 having negative (-) charges move toward the second substrate 40. In this state, when light is input from the outside, that is, the upper portion of the second substrate 40, the input light is reflected by the black particles 76, so that the electrophoretic display device is implemented with black.

On the contrary, when a positive voltage is applied to the pixel electrode 18, the common electrode 42 of the second substrate 40 has a negative potential, so that the white particles 74 having a positive charge The black particles 76 moving to the second substrate 40 and having a negative charge are moved to the first substrate 20. In this state, when light is input from the outside, that is, the upper portion of the second substrate 40, the input light is reflected by the white particles 74, so that the electrophoretic display device is implemented with white.

However, the following problem occurs in the conventional electrophoretic display device 1 having the above structure.

In the conventional electrophoretic display device 1, the first substrate 20 and the second substrate 40 are separately manufactured, and then the first substrate 20 and the second substrate 40 are bonded by the adhesive layer 56. It is completed by. That is, a thin film transistor for driving unit pixels and a pixel electrode 18 for applying an electric field to the electrophoretic layer 60 are formed on the first substrate 20 and are common on the second substrate 40 in a separate process. After the electrode 42, the electrophoretic layer 60, and the adhesive layer 56 are formed, the first substrate 20 and the second substrate 40 are bonded to each other.

However, since the unit pixels of the electrophoretic display device are generally formed in a small size of less than 150 micrometers in width and length, it is very difficult to align the electrophoretic layer to exactly match this size. If the first substrate on which the electrophoretic layer and the thin film transistor are formed is not aligned correctly, the electric field may not be correctly transferred to the electrophoretic particles, which may cause a driving error.

In addition, since the first substrate 20 and the second substrate 40 are each manufactured on different processes, the first substrate 20 and the second substrate 40 must be transported by a conveying means and then bonded to each other in the bonding process.

Meanwhile, the common electrode 42 is formed on the second substrate 40, the electrophoretic layer 60 is applied, and then the adhesive layer 56 is applied. In order to transfer the second substrate 40 to the bonding process to bond the first substrate 20 with each other, in order to prevent the adhesion of the adhesive layer 56 from being lowered or from adhering to the adhesive layer 56, the adhesive layer ( 56) must be transported with the protective film attached. In order to attach the transferred second substrate 40 to the first substrate 20, the protective film must be peeled off from the second substrate 40. Static electricity is generated during the peeling process of the protective film. Misalignment was induced in the initial arrangement of the electrophoretic particles, causing a comb-shaped moire during operation of the electrophoretic display device.

As described above, in the conventional electrophoretic display device, since the first substrate 20 and the second substrate 40 are manufactured in different processes, the first substrate 20 and the second substrate 40 when the electrophoretic layer is bonded. There is a problem that misalignment occurs or the process becomes complicated, and static electricity is generated when the adhesive layer is peeled off, resulting in poor image quality.

The present invention is to solve the above problems, by forming the electrophoretic layer directly on the substrate on which the thin film transistor is formed to prevent misalignment between the electrophoretic layer and the first substrate, to reduce the manufacturing cost and simplify the manufacturing process An object of the present invention is to provide an electrophoretic display device and a method of manufacturing the same.

Another object of the present invention is to provide an electrophoretic display device and a method of manufacturing the same, by which the first substrate forms at least a triple barrier in the outer region to improve the bonding strength of the first substrate and the second substrate and minimize the area of the bezel. To provide.

In order to achieve the above object, the electrophoretic display device according to the present invention includes a first substrate and a second substrate comprising a plurality of pixels consisting of an image display area and an image non-display area; A thin film transistor formed on each pixel on the first substrate; A protective layer on the first substrate on which the thin film transistor is formed; A pixel electrode formed in the image display area on the protective layer; Barrier ribs formed on the non-display area on the passivation layer; An electrophoretic layer formed in the image display area inside the barrier rib above the protective layer and in contact with the pixel electrode; A first barrier formed along the periphery of the first substrate; At least one second barrier and a third barrier, which are formed along the outer periphery of the first substrate and are disposed at both sides of the first barrier to be spaced apart from the first barrier by a predetermined distance to form a space between the first barrier and the first barrier ; A sealing material applied to the upper surface and the space of the first barrier to seal the first substrate and the second substrate; And a common electrode formed on the second substrate.

The electrophoretic layer is composed of at least one particle and a dispersion medium of white particles, black particles, and color particles. The 1-3 barrier is made of the same material as the partition wall.

At least one groove is formed on the upper surface of the first barrier to fill the sealing material in the groove, thereby improving the surface area of the upper surface of the first barrier and bonding force between the first substrate and the second substrate by the pressure difference between the inside and the outside of the groove. To improve.

In addition, the electrophoretic display device manufacturing method according to the present invention comprises the steps of providing a first substrate and a second substrate comprising an image display area and an image non-display area; Forming a thin film transistor in an image display area on the first substrate; Forming a protective layer on the first substrate on which the thin film transistor is formed; Forming a pixel electrode in the image display area on the protective layer; Forming a partition wall defining a plurality of pixels in an image non-display area of the protective layer; Forming a first partition on an outer region of the first substrate; Forming at least one second barrier wall and a third barrier wall on both sides of the first partition wall of the outer region of the first substrate; Filling an electrophoretic material into the pixel inside the partition wall; Forming a common electrode on the second substrate; Dropping a sealing material over the first barrier to apply a sealing material to the upper portion of the first barrier and the cavity between the first barrier and the second barrier and the third barrier; And bonding the first substrate to the second substrate.

In the present invention, since the electrophoretic layer is directly applied to the substrate on which the thin film transistor is formed, a protective film for protecting the adhesive layer or the adhesive layer for bonding the electrophoretic layer compared to the conventional electrophoretic layer formed on a separate substrate is In addition to reducing manufacturing costs, the electrophoretic layer can be formed in-line on an existing thin film transistor manufacturing line, thereby simplifying the manufacturing process. In addition, since the electrophoretic layer is directly formed on the array substrate, misalignment does not occur in the alignment process of aligning the electrophoretic layer and the array substrate.

In addition, in the present invention, the bonding force between the first substrate and the second substrate may be improved when the electrophoretic display panel is bonded.

In addition, in the present invention, the bezel of the electrophoretic display device may be slimmed by minimizing the width of the sealing area when the electrophoretic display panel is bonded, and the sealing reliability may be improved.

1 is a view showing a conventional electrophoretic display device.
2 is a view showing an electrophoretic display device according to the present invention.
3 illustrates a pixel structure of an electrophoretic display device according to the present invention.
4A-4G illustrate a method of manufacturing an electrophoretic display device according to the present invention.
5A and 5B show a method of forming an electrophoretic layer of the electrophoretic display device according to the present invention, respectively.

Hereinafter, an electrophoretic display device according to the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, the electrophoretic layer is formed on the first substrate on which the thin film transistor is formed. That is, in the present invention, the electrophoretic layer is formed in the thin film transistor manufacturing process. Therefore, since the electrophoretic layer can be formed using the manufacturing equipment of the thin film transistor, the electrophoretic display device is completed by bonding the second substrate to the first substrate after forming the electrophoretic layer on the substrate in another process. Compared with the conventional method, the manufacturing process can be greatly simplified.

In a conventional electrophoretic display device manufacturing process of forming an electrophoretic layer on a second substrate, the electrophoretic layer is supplied from another factory or even another component company and transferred to a manufacturing factory where a thin film transistor is formed. Since the manufacturing process is delayed and cumbersome because it must be bonded to the first substrate, there is a problem that the second substrate is damaged in the process of transferring the second substrate by a transfer means such as a vehicle.

On the other hand, in the present invention, since the electrophoretic layer is formed on the first substrate by using the existing thin film transistor manufacturing equipment, it is possible to quickly manufacture the electrophoretic display device.

In addition, in the present invention, triple sealing walls are formed in the outer region of the electrophoretic display device to minimize the width of the sealing area when the electrophoretic display panel is bonded, thereby reducing the bezel of the electrophoretic display device as well as sealing. It is possible to improve the reliability of.

2 is a view schematically showing the structure of an electrophoretic display device according to the present invention.

As shown in FIG. 2, the electrophoretic display device 101 according to the present invention is formed between the first substrate 120 and the second substrate 140, and the substrate 120 and the second substrate 140. A plurality of partitions 180 for partitioning pixels, an electrophoretic layer 160 formed in an image display area inside the partitions 180, and an outer surface of the electrophoretic display element, the first substrate 120 and the first substrate 120. Sealing barriers 190a, 190b and 190c for bonding and sealing the second substrate 140 and the first and second substrates 120 and 140 to apply an electric field to the electrophoretic layer 160. The pixel electrode 118 and the common electrode 142 are formed.

The genital electrophoretic display device 101 is composed of a plurality of pixels divided into an image display area and an image non-display area, and the partition wall 180 is formed in a matrix shape in the image non-display area to display the electrophoretic display device 101. Define the pixel. Although not shown in the drawing, the pixels are arranged in a matrix form throughout the electrophoretic display device 101.

An electrophoretic material is filled in the partition 180 to form an electrophoretic layer 160. The electrophoretic material includes white particles 164 and black particles 165 having positive and negative charge characteristics, and the white particles 164 and black when an electric field is applied between the pixel electrode 118 and the common electrode 142. As the particles 165 or the color particles move to the second substrate 140, the particles 165 or the color particles reflect or absorb light incident from the outside to implement white and black, or desired colors.

The partition wall 180 is formed between the pixel and the pixel to partition the pixel of the electrophoretic display device 101, and the electrophoretic material is filled therein to form the electrophoretic layer 160. That is, in the conventional electrophoretic display device, after the electrophoretic layer is attached to the second substrate by a separate process from the first substrate, the second substrate is attached to the second substrate again, so that the electrophoretic layer is attached to the second substrate. There is a need for a protective film and the like to protect the adhesive film, the process is complicated and there is a problem that the quality of the image quality is poor due to the static electricity generated during the peeling of the adhesive film, the electrophoretic material directly in the partition wall This problem does not occur because it is formed.

Three sealing barriers 190a, 190b, and 190c are formed along the outer periphery of the electrophoretic display device 101 in the outer region of the electrophoretic display device 101. In this case, the barriers 190a, 190b, and 190c are formed to be spaced apart from the partition wall 180 formed in the outermost region of the electrophoretic display device 101.

A sealing material is coated on an upper surface of the first barrier 190a formed at the center of the barriers 190a, 190b, and 190c, and the first barrier 190a and the second barrier 190b and the third barrier 190 on both sides thereof ( The sealing material 194 is filled in the space 193 between 190c.

The reason for forming the barriers 190a, 190b, and 190c in the present invention as described above is as follows.

The first substrate 120 and the second substrate 140 are bonded to each other after the end of the process, the sealing material is applied to the upper surface of the partition wall 180 for this bonding and the second substrate 140 by the sealing material It is attached to the first substrate 120. However, when the sealing material is applied to the upper surface of the partition wall 180 as described above, the sealing material on the upper surface of the upper surface by the pressure applied to the first substrate 120 and the second substrate 140 rides on the inner and outer walls of the partition wall from the upper surface. It flows into and out of the electrophoretic display element 101.

As a result, when the sealing material penetrates into the interior of the electrophoretic display device 101, contamination occurs in the electrophoretic layer 160, and a defect occurs in the electrophoretic display device, and the sealing material is electrophoretic display device 101. In case of leaking to the outside, defects occur when the electrophoretic display device is assembled to the outer case.

Furthermore, when the sealing material flows from the upper surface of the partition wall 180 to the lower portion thereof, only the amount of the sealing material smaller than the set amount remains on the upper surface of the partition wall 180, so that the first substrate 120 and the second substrate as the sealing material. When the substrate 140 is bonded, the bonding force and the sealing force of the first substrate 120 and the second substrate 140 are smaller than the set bonding force and the sealing force. Therefore, impurities such as air and moisture penetrate into the electrophoretic display device 101 from the outside, thereby degrading the quality and reliability of the electrophoretic display device 101.

However, in the present invention, a plurality of barriers 190a, 190b, 190c are formed in the outer region of the electrophoretic display element 101 to surround the electrophoretic display element 101, and among the barriers 190a, 190b, 190c, Since the sealing material 194 is positioned in the space 193 formed between the top surface of the first barrier 190a and the barriers 190a, 190b, and 190c, the first substrate 120 and the second substrate 140 may be bonded to each other. In this case, the sealing material 194 may not only prevent a problem caused by flowing into and out of the partition wall 180, but also prevent a decrease in the bonding force and the sealing force of the first substrate 120 and the second substrate 140. You can do it.

In the electrophoretic display device 101 having the above structure, the first barrier 190a at the center of the three barriers 190a, 190b, and 190c is attached to the second substrate 140 by a sealing material applied on the upper surface thereof. The 120 and the second substrate 140 are bonded to each other, and the second barrier 190b and the third barrier 190c on both sides of the first barrier 190a block the flow of the sealant 194 outside the set area to seal the sealant. To minimize the width of 194.

Grooves 192 are formed on the upper surface of the first barrier 190a. The groove 192 increases the area of the upper surface of the first barrier 190a. Since the sealing member 194 is filled therein, the groove 192 increases the surface area in contact with the sealing member 194. ) And the adhesion of the second substrate 140 can be improved. In addition, since the pressure is applied to the groove 192 and the second substrate 140 when the first barrier 190a is attached to the second substrate 140, the pressure in the inner space of the groove 192 is lower than the external pressure. As a result, the adhesive force between the first barrier 190a and the second substrate 140 may be further improved by the pressure difference.

Although only one groove 192 is formed in the drawing, a plurality of grooves 192 may be formed on an upper surface of the first barrier wall 190a.

3 is a diagram showing the structure of one pixel of the electrophoretic display device 101 having the above structure. In this case, the pixels of the electrophoretic display device 101 are pixels of the outermost region of the electrophoretic display device 101, and adjacent barriers 190a, 190b, and 190c are also disclosed.

As shown in FIG. 3, the electrophoretic display device according to the present invention includes a first substrate 120 and a second substrate 140 made of transparent glass or plastic and including an image display area and an image non-display area. A thin film transistor formed on the first substrate 120, a protective layer 124 formed on the first substrate 120 on which the thin film transistor is formed, and an image display area on the protective layer 124 to form an image signal from the outside. Is input to the pixel electrode 118, the barrier rib 180 formed in the image non-display area on the passivation layer 124 to define a plurality of pixels, and the first substrate 120 on the passivation layer 124. ) A plurality of barriers (190a, 190b, 190c) formed on the outside, the electrophoretic layer 160 formed in the partition 180, the common electrode 142 formed on the second substrate 140, and the first The first substrate 120 and the second substrate 140 are combined to fill the space 193 between the top surface of the first barrier 190a and the barriers 190a, 190b, and 190c. It is made of a sealing material 194 sealing at the same time good.

The thin film transistor includes a gate electrode 111 formed on the first substrate 120, a gate insulating layer 122 formed on the gate electrode 111, and an amorphous silicon (a-Si) formed on the gate insulating layer 122. The semiconductor layer 113 is formed of a semiconductor material as described above, and a source electrode 115 and a drain electrode 116 formed on the semiconductor layer 113.

The protective layer 124 is made of an organic insulating material such as BCB (Benzo Cyclo Butene) or photo acryl, and at this time, a contact hole 117 is formed in the protective layer 124 on the drain electrode 116 of the thin film transistor. The pixel electrode 118 formed on the passivation layer 124 is electrically connected to the drain electrode 116 of the thin film transistor through the contact hole 117.

The partition wall 180 is formed of an organic insulating material and the like, and the electrophoretic layer 160 is formed therein to serve to seal the electrophoretic material of the electrophoretic layer 160 and to partition the pixel from the pixel. Also do.

The electrophoretic layer 160 is composed of white particles 164 having positive charge characteristics and black particles 166 having negative charge characteristics. Although not shown in the drawing, the electrophoretic layer 160 includes color particles such as cyan, magenta, and yellow, or color particles such as R, red, G, and blue. May be included.

The white particles 164 implements white. That is, when a voltage is applied between the pixel electrode 118 and the common electrode 142 so that the white particles 164 having charge characteristics move to the second substrate 140 side, incident from the outside of the second substrate 140 occurs. The reflected light is reflected by the white particles 164 to express white on the screen of the electrophoretic display device.

The black particles 165 implement black. That is, when a voltage is applied between the pixel electrode 118 and the common electrode 142 to move the black particles 165 having charge characteristics toward the second substrate 140, incident from the outside of the second substrate 140 occurs. The light is absorbed by the black particles 165, and black is displayed on the screen of the electrophoretic display device.

In addition, when the electrophoretic layer 160 includes color particles, the color particles may be colored particles such as cyan, magenta, yellow, or red (R), green (G), or blue (B) particles. Color particles such as (Blue) implement color. That is, when voltage is applied between the pixel electrode 118 and the common electrode 142 to move the color particles having charge characteristics toward the second substrate 140, light incident from the outside of the second substrate 140 The color corresponding to the pixel is reflected on the screen of the electrophoretic display device reflected by the color particles 165, and the desired color may be realized by the combination of these colors.

The electrophoretic material includes a dispersion medium such as a liquid polymer. In the dispersion medium, the white particles 164 and the black particles 165 are injected therein so that the white particles 164 and the black particles 165 move in the dispersion medium according to the application of a voltage. The dispersion medium may include air. That is, instead of a specific liquid dispersion medium such as a liquid polymer, air may act as a medium for moving the white particles 164 and the black particles 165. In addition, the electrophoretic layer 160 may not include a dispersion medium. In this case, as the voltage is applied, the white particles 164 and the black particles 165 are moved by the electric field, thereby realizing an image.

On the other hand, when a liquid polymer is used as the dispersion medium, the liquid polymer uses a transparent liquid polymer, but a color liquid polymer having a color corresponding to the color of the pixel may be used. For example, a pixel containing magenta colored cyan particles is filled with a magenta liquid polymer, and a pixel containing cyan magenta colored particles is filled with a cyan liquid polymer, and a yellow colored yellow particle is included. The color is filled with a yellow liquid polymer.

The barriers 190a, 190b, and 190c may be formed of an organic insulating material, or the like. The barriers 190a, 190b, and 190c may be formed of the same material as the partition wall 182 by the same process or by different materials.

At this time, the height of the barrier 182 is formed to about 10㎛ or more, in particular about 10-50㎛ and the line width is formed to about 10-5000㎛, especially about 100-1000㎛.

Although only a structure in which three barriers 190a, 190b and 190c are formed in the figure is shown, four or more barriers 190a, 190b and 190c may be formed.

In addition, the shape of the barriers 190a, 190b, 190c (that is, the shape of the barriers 190a, 190b, 190c when viewed from above) may be variously formed. In the drawing, the barriers 190a, 190b, and 190c are formed in a straight line along the outer regions of the first and second substrates 120 and 140, but the barriers 190a, 190b, and 190c are formed in a zigzag shape. It can also be formed along the outer region meandering.

The sealing material 194 is filled in the upper surface of the first barrier 190a and the groove 192 formed in the center of the barriers 190a, 190b and 190c, and the space 193 between the barriers 190a, 190b and 190c. The first substrate 120 and the second substrate 140 are bonded to each other and sealed at the same time.

The grooves 192 and the spaces 193 are formed along the periphery of the electrophoretic display device 101 along the barriers 190a, 190b, and 190c.

The second barrier 190b and the third barrier 190c serve to limit the position of the sealing member 194 filled in the space 193 so that the sealing member 194 is formed at another place, for example, a failure turn. It can be prevented from spreading to an area other than the sealing area, that is, the inner side or the outer side of the sealing area. Although the sealing material 194 may use a variety of materials, the ultraviolet curing sealing material or the thermosetting sealing material is mainly used.

The pixel electrode 118 is made of a transparent conductive material or an opaque metal, and is electrically connected to the drain electrode 116 of the thin film transistor through the contact hole 117 formed in the protective layer 124.

As shown in the figure, the pixel electrode 118 may be formed only in the image display area on the passivation layer 124, but the pixel electrode 118 is disposed on the passivation layer 124 and the sidewalls of the partition wall 180. It can be formed by extending to the top.

As described above, when the pixel electrode 118 is formed by extending on the protective layer 124 and on the sidewalls, the pixel electrode 118 at the bottom of the barrier wall 180, that is, the barrier wall 180 and the protective layer is formed. The dead area generated in the corner area of 124 can be removed to improve the aperture ratio, the contrast, and the response speed.

The common electrode 142 is made of a transparent conductive material such as ITO or IZO.

In the electrophoretic display device 101 according to the present invention having the above-described configuration, the partition wall 180 is directly formed on the first substrate 120, and the electrophoretic layer 160 is also the partition wall of the first substrate 120. And the electrophoretic layer 160 is directly formed on the pixel electrode 118 to be in direct contact with the pixel electrode 118, and thus, the electrophoretic layer 160 is different from the conventional electrophoretic display device. Since there is no need for a separate adhesive layer for attaching the electrophoretic layer 160 between the pixel electrode 118 and the protective layer 124, the manufacturing process can be simplified to reduce the manufacturing cost.

In addition, in the present invention, the barriers 190a, 190b, and 190c are formed to form the first substrate 120 and the second substrate 140 by the groove 192 of the first barrier 190a and the sealing member 194 on the upper surface. Since the bonding and sealing are performed, the bonding force between the first substrate 120 and the second substrate 140 is good and the sealing force of the first substrate 120 and the second substrate 140 can be prevented from penetrating the electrophoretic display device 101 with moisture or air. Will be. In addition, since the sealing material 194 can be prevented from being widely spread by the second barrier 190b and the third barrier 190c, the bezel can be minimized when the electrophoretic display device 101 is assembled. do.

5A-5G illustrate a method of manufacturing an electrophoretic display device according to the present invention. Although the electrophoretic display device is substantially composed of a plurality of unit pixels, in the drawings, only the pixels of the outer region including the barrier are illustrated in the drawings.

First, as shown in FIG. 5A, Cr, Mo, Ta, Cu, Ti, Al or Al alloys are formed on a first substrate 120 including an image display unit and an image non-display area and made of a transparent material such as glass or plastic. After stacking the opaque metal having good conductivity by the sputtering process and etching by the photolithography process to form the gate electrode 111, the first substrate on which the gate electrode 111 is formed The gate insulating layer 122 is formed by stacking an inorganic insulating material, such as SiO ₂ or SiNx, by the CVD (Chemicla Vapor Deposition) method over the entirety of the 120.

Subsequently, as illustrated in FIG. 5B, a semiconductor material such as amorphous silicon (a-Si) is deposited on the first substrate 120 by CVD and then etched to form a semiconductor layer 113. In addition, although not shown in the drawing, an ohmic contact that ohmic-contacts the source electrode and the drain electrode to be subsequently formed with a semiconductor layer 113 by doping impurities or stacking amorphous silicon added with impurities to a part of the semiconductor layer 113. To form an ohmic contact layer.

Thereafter, as illustrated in FIG. 5C, an electrically conductive opaque metal such as Cr, Mo, Ta, Cu, Ti, Al, or Al alloy is laminated on the first substrate 120 by sputtering and then etched to form a semiconductor. On the layer 113, strictly speaking, the source electrode 115 and the drain electrode 116 are formed on the ohmic contact layer, and then the entire first substrate 120 having the source electrode 115 and the drain electrode 116 formed thereon. A protective layer 124 is formed by stacking an organic insulating material such as BCB (Benzo Cyclo Butene) or photo acryl.

In addition, although not shown, the protective layer 124 may be formed of a plurality of layers. For example, the protective layer 124 may be formed of a double layer of an organic insulating layer made of an organic insulating material such as BCB or photoacryl and an inorganic insulating layer made of an inorganic insulating material such as SiO ₂ or SiNx. It may be formed of an insulating layer, an organic insulating layer and an inorganic insulating layer. As the organic insulating layer is formed, the surface of the protective layer 124 is formed to be flat, and the interface characteristic with the protective layer 124 is improved by applying the inorganic insulating layer.

In addition, a contact hole 117 is formed in the protective layer 124 to expose the drain electrode 116 of the thin film transistor to the outside.

Subsequently, as illustrated in FIG. 5D, the pixel electrode 118 is formed in the image display area on the passivation layer 124. In this case, the pixel electrode 118 is electrically connected to the drain electrode 116 of the thin film transistor through the contact hole 117.

The pixel electrode 118 may be formed by stacking a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO), metal such as Mo and AlNd, and then etching the same by a photolithography method. In addition, the pixel electrode 118 may be formed of a plurality of metal layers. That is, it may be formed by successively stacking a plurality of metal layers, such as Cu and MoTi, and then etching by a photolithography method. The pixel electrode 118 may be formed using carbon nanotubes or water-soluble conductive polymers.

Thereafter, as shown in FIG. 2E, the barrier 180 and the barriers 190a, 190b, and 190c are formed on the protective layer 124. The partition wall 180 is formed in the image non-display area of the first substrate 120 and substantially partitions the unit pixel. Although not illustrated in the drawing, the partition wall 180 is formed along a boundary area of pixels arranged in a matrix shape on the first substrate 120, so that the partition wall 180 also has a matrix shape on the first substrate 120. Is formed.

The barriers 190a, 190b, and 190c are formed to be spaced apart from the outermost partition wall 180 at a distance from the partition wall 180 arranged in a matrix.

The partition wall 180 may be formed by laminating an insulating layer made of a resin, or the like by etching using a photolithography method using a photoresist, or may be formed by laminating a photosensitive resin and then etching by a photolithography method. In addition, the partition wall 180 may be formed by printing the patterned partition wall 180 by a printing method such as a printing roll, or the like. The pattern 180 is formed by an imprint method of applying pressure to the resin layer using a patterned mold. It could be.

In practice, the formation of the partition wall 180 is not limited by a specific method. The specific method described above is for convenience of description and is not intended to limit the present invention. The partition 180 may be formed by various known methods.

The barriers 190a, 190b, and 190c may also be formed by the same method as the barrier 180. That is, the barrier 182 may be formed by laminating resins or photosensitive resins and then etching them by a photolithography method or an imprint method.

In this case, the barriers 190a, 190b, and 190c may be simultaneously formed by the same process as the partition wall 180 or may be formed by a separate process from the partition wall 180.

When the barriers 190a, 190b, and 190c are formed, the first barrier 190a, the second barrier 190, and the third barrier 190c are formed at a predetermined distance from each other, and the upper surface of the first barrier 190a is formed. A portion of the silver is removed to form the groove 192.

Meanwhile, in the drawing, the partition electrode 180 is formed after the pixel electrode 118 is formed on the passivation layer 124. However, after the partition wall 180 is first formed in the image non-display area on the passivation layer 124, The pixel electrode 118 may be formed in the image display area on the passivation layer 124. In this case, the protective layer 124 and the partition wall 180 may be simultaneously formed of the same material. For example, after the insulating layer is thickly formed, the insulating layer is removed by a diffraction mask or a halftone mask to simultaneously form the partition wall 180 and the contact hole 117 or a part of the insulating layer is removed by a mold or the like. May form.

When forming the barriers 190a, 190b, and 190c, at least one groove 192 is formed by removing a portion of the upper surface of the first barrier 190a.

Thereafter, as shown in FIG. 5F, the electrophoretic material is filled in the partition wall 180. The electrophoretic material is composed of particles having positive and negative charge characteristics.

The electrophoretic material is composed of particles having positive and negative charge characteristics. In this case, the particles may be white particles 164 and black particles 165, color particles such as cyan, magenta, yellow, or R (Red), G (Green), B It may be a color particle such as (Blue).

In addition, the electrophoretic material includes a dispersion medium such as a liquid polymer. In this case, the dispersion material may be a transparent liquid polymer or a black liquid polymer or may be a color liquid polymer corresponding to a color in each pixel. The electrophoretic material may be formed of only white particles and black particles or color particles without a liquid polymer. In this case, the white particles and the black particles or the color particles are distributed in the air on the electrophoretic layer 160 and move inside the electrophoretic layer 160 as a voltage is applied.

In the case of the white particles 164, particles having good reflectance such as TiO ₂ are used, and in the case of the black particles 165, particles having black characteristics such as carbon black are used. In addition, pigments or dyes are used as the color particles.

In this case, the white particles 164 may have negative charge characteristics, the black particles 165 may have positive charge characteristics, the white particles 164 may have positive charge characteristics, and the black particles 165 may have negative charge characteristics.

6A and 6B illustrate a method of forming the electrophoretic layer 160 by filling an electrophoretic material into the partition wall 180 formed on the first substrate 120.

The method illustrated in FIG. 36 relates to an inkjet method or a nozzle method. As shown in FIG. 6A, an electrophoretic material 160a is filled in a syringe (or nozzle) 185 and then the first substrate ( 120) The syringe 185 is positioned on the top. Thereafter, the partition wall 180 is moved by moving the syringe 185 on the first substrate 120 in a state where pressure is applied to the syringe 185 by an external air supply device (not shown). The electrophoretic material 160a is dropped therein to form the electrophoretic layer 160 on the first substrate 120.

The method illustrated in FIG. 6B relates to a squeeze method, and as shown in FIG. 6B, after the electrophoretic material 160a is applied to the first substrate 120 on which the plurality of partition walls 180 are formed, a squeeze bar ( The electrophoretic material 160a is filled into the partition 180 in the unit pixel by the pressure of the squeeze bar 187 by moving on the first substrate 120 by 187 to form the electrophoretic layer 160. .

Of course, the present invention is not limited to the method as described above. The method described above shows an example of the process of forming the electrophoretic layer 160 that can be used in the present invention, and the present invention is not limited to this specific process. For example, various electrophoretic layer 160 forming processes such as casting printing, bar coating printing, screen printing, and mold printing may be applied to the present invention.

Subsequently, as illustrated in FIG. 5G, the common electrode 142 is formed by stacking a transparent conductive material such as ITO or IZO on the second substrate 140 made of a transparent material such as glass or plastic. Thereafter, the sealing material 194 is dropped on the upper surface of the first barrier wall 190a of the first substrate 120 using a dropping device such as a syringe. The sealing material 194 dropped on the upper surface of the first barrier 190a is not only applied to the upper surface of the first barrier 190a, but also the first barrier 190a and the second barrier 190b on the upper surface of the first barrier 190a. ) Into the space 193 between the third barrier wall 190c and the sealing material 194 is filled in the space 193.

As described above, the first substrate 120 and the second substrate 140 are formed in a state where the sealing material 193 is applied to the upper surface of the first barrier wall 190a and the sealing material 193 is filled in the space 193. The first substrate 120 and the second substrate 140 are bonded to each other by applying pressure in the aligned state. In this case, the sealing member 193 is cured by applying heat or ultraviolet rays while applying pressure to the first substrate 120 and the second substrate 140 to complete the electrophoretic display device.

Meanwhile, in the drawing, the first substrate 120 and the second substrate 140 are bonded by the sealing material 194, but in order to improve the bonding strength of the first substrate 120 and the second substrate 140, It may be possible to form an adhesive layer made of an adhesive material.

Although not shown in the drawings, a color filter layer may be formed on the second substrate 140. This color filter layer is composed of R (Red), G (Green), B (Blue) color filter, and the color is realized when the electrophoretic material is composed of black particles and white particles.

In the above description, the structure of the electrophoretic display device is limited to a specific structure, but the electrophoretic display device of the present invention is not limited to the specific structure. In particular, various electrophoretic layers currently used as electrophoretic layers may be applied. That is, it may be applied to the electrophoretic layer of any structure that can be formed on the first substrate.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Accordingly, the scope of the present invention is not limited thereto, but various modifications and improvements of those skilled in the art using the basic concept of the present invention as defined in the following claims are also within the scope of the present invention.

120,140 substrate 111 gate electrode
113: semiconductor layer 115: source electrode
116: drain electrode 118: pixel electrode
124: protective layer 142: common electrode
160: electrophoretic layer 164: white particles
165 black particles 180 bulkhead
190a, 190b, 190c: Barrier grooves: 192
193: space 194: sealing material

Claims (19)

A first substrate and a second substrate including a plurality of pixels including an image display area and an image non-display area;
A thin film transistor formed on each pixel on the first substrate;
A protective layer on the first substrate on which the thin film transistor is formed;
A pixel electrode formed in the image display area on the protective layer;
Barrier ribs formed on the non-display area on the passivation layer;
An electrophoretic layer formed in the image display area inside the barrier rib above the protective layer and in contact with the pixel electrode;
A first barrier formed along the periphery of the first substrate;
At least one second barrier and a third barrier, which are formed along the outer periphery of the first substrate and are disposed at both sides of the first barrier to be spaced apart from the first barrier by a predetermined distance to form a space between the first barrier and the first barrier ;
A sealing material applied to the upper surface and the space of the first barrier to seal the first substrate and the second substrate; And
An electrophoretic display device comprising a common electrode formed on a second substrate. The method of claim 1, wherein the thin film transistor,
A gate electrode formed on the first substrate;
A semiconductor layer formed on the gate electrode; And
An electrophoretic display device comprising a source electrode and a drain electrode formed on the semiconductor layer. The electrophoretic display device of claim 1, wherein the electrophoretic layer comprises at least one of white particles, black particles, and color particles. The electrophoretic display device of claim 3, wherein the electrophoretic layer further comprises a dispersion medium in which white particles, black particles, or color particles are dispersed. The electrophoretic display device of claim 4, wherein the dispersion medium is a transparent liquid medium or a color liquid medium. The electrophoretic display device of claim 1, wherein the first to third barriers are made of the same material as the barrier ribs. The electrophoretic display device of claim 1, wherein the height of the first to third barriers is about 1 to 100 μm. 8. An electrophoretic display device according to claim 7, wherein the height of the first to third barriers is 1 to 50 mu m. The electrophoretic display device according to claim 1, wherein the width of the first to third barriers is 10 to 5000 µm. 10. The electrophoretic display device according to claim 9, wherein the width of the first to third barriers is 100 to 1000 mu m. The electrophoretic display device of claim 1, wherein at least one groove is formed on an upper surface of the first barrier, and a sealing material is filled in the groove. Providing a first substrate and a second substrate including an image display area and an image non-display area;
Forming a thin film transistor in an image display area on the first substrate;
Forming a protective layer on the first substrate on which the thin film transistor is formed;
Forming a pixel electrode in the image display area on the protective layer;
Forming a partition wall defining a plurality of pixels in an image non-display area of the protective layer;
Forming a first partition on an outer region of the first substrate;
Forming at least one second barrier wall and a third barrier wall on both sides of the first partition wall of the outer region of the first substrate;
Filling an electrophoretic material into the pixel inside the partition wall;
Forming a common electrode on the second substrate;
Dropping a sealing material over the first barrier to apply a sealing material to the upper portion of the first barrier and the cavity between the first barrier and the second barrier and the third barrier; And
A method of manufacturing an electrophoretic display device, comprising: bonding a first substrate to a second substrate. The method of claim 12, wherein the barrier rib and the first barrier are simultaneously formed. The method of claim 12, wherein the forming of the electrophoretic layer is performed using an inkjet method, a squeeze method, a casting printing method, a bar coating printing method, a screen printing method, or a mold printing method. Electrophoretic display device manufacturing method comprising the step of filling. The method of claim 12, wherein the filling of the sealing material is performed using one of an inkjet method, a squeeze method, a casting printing method, a bar coating printing method, a screen printing method, and a mold printing method. Electrophoretic display device manufacturing method comprising the step of filling. The method of claim 12, wherein the forming of the thin film transistor comprises:
Forming a gate electrode on the first substrate;
Forming a semiconductor layer on the gate electrode;
Forming a source electrode and a drain electrode on the semiconductor layer. The method of claim 12, wherein the electrophoretic material comprises at least one of white particles, black particles, and colored particles. 18. The method of claim 17, wherein the electrophoretic material further comprises a dispersion medium in which white particles, black particles, or color particles are dispersed. The method of claim 12, wherein at least one groove is formed on an upper surface of the first barrier to fill a sealing material.

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