KR20100077096A - Electrophoretic display device and method for manufacturing the same - Google Patents

Abstract

PURPOSE: An electrophoresis display device and a method for manufacturing the same are provided to prevent misalign which is generated when an upper array unit and a lower array unit are going on a collaboration process. CONSTITUTION: A lower array unit(200) comprises a common electrode(201b), pixel electrode(222a) and thin film transistor. A gate insulating layer(210) is in between the common electrode and pixel electrode which is formed on a first substrate. The thin film transistor is electrically connected to the pixel electrode. An upper array unit(300) comprise a color filter layer(224), a plurality of partitions, and electrophoresis material layer(230). The plurality of partition wall defines a unit block.

Description

Electrophoretic Display Device and Method for Manufacturing the Same

The present invention relates to an electrophoretic display device and a manufacturing method thereof.

A typical electrophoretic display device (EPD) has excellent flexibility and portability, and has electrophoresis, which has characteristics such as light weight (electrophoresis: a phenomenon in which charged particles move toward an anode or a cathode in an electric field). It is a kind of flat panel display using.

The electrophoretic display is a display that forms a thin film transistor array on a thin, bendable base film such as paper or plastic, and drives electrophoretic floating particles by a vertical electric field between a pixel electrode and a common electrode of the thin film transistor array. It is a display device that is also expected as paper.

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

The electrophoretic display shown in FIG. 1 is divided into a lower array unit 60 and an upper array unit 80.

The upper array unit 80 includes a common electrode 84 formed on the upper plate 82 and an electrophoretic film 90 positioned on the common electrode 84.

The upper plate 82 may be made of a flexible plastic, an easily bent base film, a flexible metal, or the like.

The electrophoretic film 90 includes a capsule 92 including charged pigment particles, and upper and lower protective layers 96 and 94 positioned above and below the capsule 92.

The capsule 92 includes black dye particles 92a in response to a positive voltage, white dye particles 92b in response to a negative voltage, and a solvent 92c.

The upper and lower protective layers 96 and 94 block the flow of the spherical capsule 92 and serve to protect the capsule 92. The upper and lower protective layers 96, 94 are made of flexible plastic, easily bent base film, flexible metal, or the like.

The lower array unit 60 includes a gate line (not shown) and a data line (not shown) formed to intersect the gate insulating film 44 on the lower plate 42, and a thin film transistor formed at each intersection thereof. Transistor (hereinafter referred to as "TFT") 6 and a pixel electrode 18 formed in a cell region provided in a cross structure thereof.

The bottom plate 42 is made of flexible plastic, easily bent base film, flexible metal, or the like.

The TFT 6 includes a gate electrode 8 to which a gate voltage is supplied, a source electrode 10 connected to a data line, a drain electrode 12 connected to a pixel electrode 18, a gate electrode 8, An active layer 14 is provided that overlaps and forms a channel between the source electrode 10 and the drain electrode 12.

The active layer 14 is formed to overlap the source electrode 10 and the drain electrode 12, and further includes a channel portion between the source electrode 10 and the drain electrode 12. An ohmic contact layer 48 for ohmic contact with the source electrode 10 and the drain electrode 12 is further formed on the active layer 14. Here, the active layer 14 and the ohmic contact layer 48 are commonly referred to as a semiconductor pattern 45.

The pixel electrode 18 is in contact with the drain electrode 12 through the contact hole 17 exposing the drain electrode 12 through the protective film 50 protecting the TFT 6.

The upper array portion 80 and the lower array portion 60 having such a structure are bonded to each other by an adhesive 86 to form an electrophoretic display device.

Such an electrophoretic display includes a pixel voltage signal supplied to a data line in response to a gate voltage supplied to the gate electrode 8 of the lower array unit 60 to the pixel electrode 18 via a channel of the TFT 6. When charged and the reference voltage is supplied to the common electrode 84 of the upper array unit 80, the white dye particles 92b and the black dye particles 92a in the capsule 92 are formed by the electrophoretic phenomenon caused by the electric field. It is possible to realize black or white while dividing.

Meanwhile, the electrophoretic display device illustrated in FIG. 1 has a disadvantage in that only two colors, black and white, are implemented and conventional colors cannot be realized.

Accordingly, a technique for realizing color by introducing an upper array substrate structure of a liquid crystal display device into an electrophoretic display device has been proposed.

2 is a diagram illustrating an electrophoretic display device capable of realizing color by introducing an upper array substrate of a conventional liquid crystal display into an electrophoretic display device.

The electrophoretic display illustrated in FIG. 2 has a structure in which the upper array portion 80 and the lower array portion 60 are bonded through the sealant 125.

The structure of the lower array unit 60 has the same structure as that shown in FIG.

The upper array unit 80 includes red, green, and blue color fills 138 and a common electrode 84 formed on the entire surface of the color filter 138 on the upper glass substrate 102, and also charge pigment particles. It is provided with an electrophoretic film 90 in which capsules 92 containing particles are arranged.

The electrophoretic display device including the color filter 138 may implement a color image like the liquid crystal display device.

However, in the electrophoretic display device, the manufacturing process of the upper array unit 80 and the lower array unit 60 is complicated, thereby increasing the manufacturing cost.

In addition, there is a fear that a misalignment may occur by adding a bonding process to the upper array portion 80 and the lower array portion 60.

SUMMARY OF THE INVENTION An object of the present invention for solving the above-described problems is to provide an electrophoretic display device and a method of manufacturing the same, which can reduce the manufacturing cost and facilitate the manufacturing process, and can prevent misalignment.

An electrophoretic display device according to the present invention for solving the above problems is a lower array unit having a common electrode and a pixel electrode formed on a first substrate with a gate insulating film interposed therebetween, and a thin film transistor electrically connected to the pixel electrode. And an upper array unit including a color filter layer formed on the lower array unit, a plurality of partition walls formed on the color filter layer and defining a unit block, and an electrophoretic material layer formed between the partition walls. The barrier rib is stacked with an insulating pattern for the barrier rib and a common electrode pattern for the barrier rib, and the barrier common electrode pattern is connected to the common electrode of the lower array unit through a connection electrode pattern.

The electrophoretic material layer is filled with a transparent fluid containing charged black particles.

The unit block is one unit pixel area in which the pixel electrode is formed, or a plurality of the unit blocks is one unit pixel area.

A second substrate is further formed on the barrier and the layer of electrophoretic material.

Method of manufacturing an electrophoretic display device according to the present invention for solving the above problems is the step of forming a gate electrode, a common electrode and a gate pad on a first substrate, and on the substrate on which the gate electrode and the common electrode is formed Forming a gate insulating film, forming a source and drain electrode and a data pad on the substrate on which the gate insulating film is formed, and forming a protective film on the substrate on which the source and drain electrodes are formed, and then patterning the drain electrode. Forming a drain contact hole for exposing, a data pad contact hole for exposing the data pad, a gate pad contact hole for exposing the gate pad, and a common electrode contact hole for exposing the common electrode; The first metal film on the first substrate on which the electrodes are formed and patterned to form a first metal layer before draining through the drain contact hole. And a pixel electrode connected to the common electrode, a connection electrode pattern connected to the common electrode through the common electrode contact hole, a gate pad connection electrode connected to the gate pad through the gate pad contact hole, and the data pad through the data pad contact hole. Forming a data pad connection electrode to be connected; forming a color filter pattern on the first substrate on which the pixel electrode is formed; and forming a second metal film and an insulating film on the first substrate on which the color filter pattern is formed. Forming a barrier rib defining a unit block, forming a layer of electrophoretic material in a unit block defined by the barrier ribs, and forming a barrier rib on the first substrate on which the electrophoretic material and the barrier rib are formed. Forming a second substrate.

The first metal layer includes an opaque metal layer formed of any one of Al, AlNd, and Ag, and a transparent metal layer formed of any one of ITO, IZO, and ITZO.

The passivation layer is formed by stacking an inorganic insulating material and an organic insulating material, and a passivation layer having the data pad contact hole and the gate pad contact hole is formed only of the inorganic insulating material.

As described above, the electrophoretic display device and the manufacturing method thereof according to the present invention are formed by integrating a color filter pattern and an upper array portion on which an electrophoretic material layer is formed on a lower array portion on which TFTs are formed, thereby forming an upper array portion and a lower array portion, respectively. There is an effect that can prevent the process complexity and the increase in manufacturing cost caused by manufacturing.

In addition, the electrophoretic display device and the method of manufacturing the same according to the present invention as described above are formed integrally with the upper array portion and the lower array portion, it is possible to prevent the misalignment generated during the bonding process of the upper array portion and the lower array portion. It has an effect.

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

3 is a cross-sectional view of an electrophoretic display device according to the present invention.

The electrophoretic display device illustrated in FIG. 3 includes a lower array unit 200 and an upper array unit 300.

First, the lower array unit 200 intersects a gate line (not shown) and a data line (not shown) that define a pixel area by crossing the gate insulating layer 210 therebetween on the first substrate 201, and the intersection thereof. Thin Film Transistors ("TFT", T) formed in each section, the pixel electrode 222a formed in the pixel region, and the common electrode 201b formed on the same layer as the gate line (not shown). It is provided.

The TFT T includes a gate electrode 201a to which a gate voltage is supplied, a source electrode 212a protruding from a data line (not shown), a drain electrode 212b connected to the pixel electrode 222a, and a gate electrode. An active layer (not shown) overlapping the 201a and forming a channel between the source electrode 212a and the drain electrode 222a is provided. The active layer (not shown) is formed to overlap the source electrode 212a and the drain electrode 222a and further includes a channel portion between the source electrode 212a and the drain electrode 222a. An ohmic contact layer (not shown) for ohmic contact with the source electrode 212a and the drain electrode 222a is further formed on the active layer (not shown). Here, the active layer (not shown) and the ohmic contact layer (not shown) are commonly referred to as a semiconductor pattern 211.

The pixel electrode 222a is connected to the drain electrode 222a through a drain contact hole that penetrates through the passivation layer 220 protecting the TFT (T) and exposes the drain electrode 222a.

The upper array unit 300 includes red, green, and blue color filter patterns 224 formed on the passivation layer 220 and the pixel electrode 222a of the lower array unit 200, and on the color filter pattern 224. Barrier ribs 228b and 226b defined in the unit block and defining unit blocks, an electrophoretic material layer 230 formed between the barrier ribs 228b and 226b, barrier ribs 228b and 226b, and It is formed of a second substrate 250 formed on the electrophoretic material layer 230.

Meanwhile, the color filter layer 224 illustrated in FIG. 3 is a view showing one color filter pattern among red, green, and blue color filter patterns.

The plurality of unit blocks define one unit pixel area.

In addition, as illustrated in FIG. 3, one unit pixel region is defined through three unit blocks and pixel electrodes 222a, but one unit pixel region is defined through one unit block and pixel electrodes. It can also be defined.

The partition walls 228b and 226b are formed by stacking the partition insulating pattern 228b and the partition common electrode pattern 226b. The partition common electrode pattern 226b includes the color filter layer 224, the passivation layer 220, and the gate insulating layer. The common electrode 201b is connected to the common electrode 201b through a common electrode contact hole through which the common electrode 201b is exposed, and the partition insulating pattern 228b is formed on the common electrode pattern 226b for the partition wall. .

The electrophoretic material layer 230 is filled with a transparent fluid 230b containing black particles 230a, and the black particles 230a carry a positive or negative charge.

The electrophoretic display device according to the present invention configured as described above may implement a black screen or a white screen by forming the common electrode pattern 226b for the partition on the side of the unit region. That is, the charged black particles 230a move in accordance with the polarities of the voltages applied to the common electrode 201b and the pixel electrode 222a, and are applied to the common electrode 201b and the pixel electrode 222a. By controlling the polarity and voltage value of the voltage, the black mode or the white mode can be implemented by controlling the movement of the black particles distributed in the common electrode pattern 226b for the partition wall connected to the common electrode 201b and the pixel electrode 222a. .

That is, when all black particles 230a are distributed in the partition common electrode pattern 226b, a white screen is displayed, and when all black particles 230a are distributed on the pixel electrode 222a, a black screen is displayed. do.

As such, the driving mode according to the black mode or the white mode will be described in more detail with reference to FIGS. 4A and 4B. In this case, it is assumed that the black particles 230a carry a (+) charge.

In this case, the electrophoretic display device displays the screen with the light reflected by the external light source.

First, as shown in FIG. 4A, when a negative voltage is applied to the pixel electrode 222a and a positive voltage is applied to the common electrode 201b (for example, the voltage is applied to the pixel electrode). A high voltage is applied to the common electrode) and the attraction force between the pixel electrode 222a and the black particles 230a acts, so that the black particles 230a are formed on the color filter pattern 22 corresponding to the pixel electrode 222a. The black particles 230a distributed on the pixel electrode 222a block all the light reflected by the external light source and display the black screen.

As shown in FIG. 4B, when a positive voltage is applied to the pixel electrode 222a and a negative voltage is applied to the common electrode 201b (for example, the voltage is applied to the pixel electrode). A low voltage is applied to the common electrode) and the attraction force between the partition common electrode pattern 226b and the black particles 230a connected to the common electrode 201b causes the black particles 230a to form the partition common electrode pattern. Since there is no black particle 230a blocking the light on the pixel electrode 222a since the movement to 226b occurs, all the light reflected by the external light source is transmitted to display the white screen.

Hereinafter, a method of manufacturing the electrophoretic display device as described above will be described in more detail.

5A to 5H are cross-sectional views illustrating a method of manufacturing an electrophoretic display device according to the present invention.

As shown in FIG. 5A, a gate metal layer is deposited on the substrate 201 and then selectively patterned to form a gate wiring (not shown), a gate electrode 201a, and a common electrode 201b in the pixel region P. FIG. ) Is formed, and the gate pad 201c is formed in the gate pad formation region GP.

The substrate 201 is defined as a pixel region P, a gate pad forming region GP, and a data pad forming region DP.

Subsequently, as shown in FIG. 5B, a gate insulating layer 210 is formed on the entire surface of the substrate 201 on which the gate electrode 201a, the common electrode 201b, and the gate pad 201c are formed.

Next, as shown in FIG. 5C, a semiconductor layer and a data metal layer are deposited on the substrate 201 on which the gate insulating layer 210 is formed, and then selectively patterned to form a data line (not shown) in the pixel region P. The semiconductor pattern 211, the source electrode 212a and the drain electrode 212b are formed, and the data pad 212c is formed in the data pad formation region DP.

In this case, the drain electrode 212b and the common electrode 201b form a storage capacitor with the gate insulating layer 210 interposed therebetween.

Subsequently, as shown in FIG. 5D, after forming the passivation layer 220 on the substrate 201 where the source electrode 212a and the drain electrode 212b are formed, the passivation layer 220 is selectively patterned. A drain contact hole 221a exposing the drain electrode 212b and a data pad contact hole 221d exposing the data pad 212c are respectively formed in the pixel region P. . In addition to patterning the passivation layer 220, the gate insulating layer 210 may be selectively patterned to expose the common electrode contact hole 221b exposing the common electrode 201b in the pixel region P, and the gate pad forming region ( Gate pad contact holes 221c exposing the gate pads 201c are respectively formed in the GP).

The passivation layer 220 is formed by stacking a film formed of an inorganic insulating material such as silicon nitride and a film formed of an organic insulating material such as a photo acrylic film.

Subsequently, a photo acrylic film is patterned from the passivation layer 220 formed in the gate pad forming region GP and the data pad forming region DP. As a result, in the passivation layer 220 in which the gate pad contact hole 221c and the data pad contact hole 221d are formed, the photo acryl layer is removed and only the silicon nitride layer remains.

Next, as illustrated in FIG. 5E, an opaque metal film and a transparent metal film are deposited on the substrate 201 on which the drain contact hole 221a and the common electrode contact hole 221b are formed, and then patterned selectively. The pixel electrode 222a connected to the drain electrode 212b through the drain contact hole 221a and the connection electrode pattern 222b connected to the common electrode 201b through the common electrode contact hole 221b. ) And a data pad through the gate pad connecting electrode 222c and the data pad contact hole 221d respectively connected to the gate pad 201c through the gate pad contact hole 221c in the gate pad forming region GP. Data pad connection electrodes 222d are formed in the formation region DP to connect with the data pads 212c.

The opaque metal film is formed of a metal film such as Al, AlNd, Ag, and the like, and the transparent metal film is formed of a metal film such as ITO, IZO, or ITZO.

As described above, in the pixel electrode 222a stacked with the opaque metal film and the transparent metal film, the opaque metal film serves as a reflection plate of the pixel region.

Next, as illustrated in FIG. 5F, a color filter layer is deposited on the substrate 201 on which the pixel electrode 222a and the first connection electrode pattern 222b are formed, and then patterned to color the pixel region P. FIG. The filter pattern 224 is formed.

Subsequently, a metal film and an insulating film are sequentially deposited on the substrate 201 on which the color filter pattern 224 is formed, and then patterned to form a partition wall in which the partition common electrode pattern 226 and the partition insulation pattern 228 are stacked. 226, 228).

The partition common electrode pattern 226 is connected to the common electrode 201b through the connection electrode pattern 222b.

The partitions 226 and 228 define a unit block, and the plurality of unit blocks define one unit pixel area. Meanwhile, as illustrated in FIG. 5F, one unit pixel region is defined through three unit blocks and the pixel electrode 222a, but one unit pixel region is defined through one unit block and the pixel electrode. It can also be defined.

Subsequently, as shown in FIG. 5G, a layer of electrophoretic material 230 is formed in the unit block formed through the partition walls 226 and 228 of the substrate 201 on which the partition walls 226 and 228 are formed.

The electrophoretic material layer 230 is filled with a transparent fluid 230b containing black particles 230a, and the black particles 230a carry a positive or negative charge.

Finally, as shown in FIG. 5H, the process is completed by forming the second substrate 250 on the entire surface of the substrate 201 on which the electrophoretic material layer 230 and the partition walls 226 and 228 are formed.

The second substrate 250 is a substrate formed for encapsulation on the first substrate 201 where the electrophoretic material layer 230 and the partition walls 226 and 228 are formed. At this time, an adhesive is applied to the surface of the second substrate 250 in contact with the first substrate 201, and the adhesive applied through UV curing is cured and encapsulated.

1 and 2 are cross-sectional views illustrating a conventional electrophoretic display device.

3 is a cross-sectional view showing an electrophoretic display device according to the present invention;

4A and 4B are cross-sectional views showing a driving mode of the electrophoretic display device according to the present invention.

5A to 5H are cross-sectional views illustrating a method of manufacturing an electrophoretic display device according to the present invention.

Claims (9)

A lower array unit including a common electrode and a pixel electrode formed on the first substrate with a gate insulating layer interposed therebetween, and a thin film transistor electrically connected to the pixel electrode; An upper array unit including a color filter layer formed on the lower array unit, a plurality of partition walls formed on the color filter layer and defining a unit block, and an electrophoretic material layer formed between the partition walls, The partition wall has an insulating pattern for partition walls and a common electrode pattern for partition walls, and the partition common electrode pattern is connected to the common electrode of the lower array unit through a connection electrode pattern. The method of claim 1, wherein the electrophoretic material layer An electrophoretic display device comprising a transparent fluid filled with charged black particles. According to claim 1, And wherein the unit block is one unit pixel region in which the pixel electrode is formed, or the plurality of unit blocks are the one unit pixel region. According to claim 1, And a second substrate on the barrier rib and the electrophoretic material layer. Forming a gate electrode, a common electrode and a gate pad on the first substrate; Forming a gate insulating film on the substrate on which the gate electrode and the common electrode are formed; Forming source and drain electrodes and a data pad on the substrate on which the gate insulating film is formed; A drain contact hole exposing the drain electrode by patterning and forming a passivation layer on the substrate on which the source and drain electrodes are formed, a data pad contact hole exposing the data pad, and a gate pad contact hole exposing the gate pad. Forming a common electrode contact hole exposing the common electrode; After forming and patterning a first metal film on the first substrate on which the contact holes are formed, a pixel electrode is connected to the drain electrode through the drain contact hole, and a connection electrode pattern is connected to the common electrode through the common electrode contact hole. Forming a gate pad connection electrode connected to the gate pad through the gate pad contact hole and a data pad connection electrode connected to the data pad through the data pad contact hole; Forming a color filter pattern on the first substrate on which the pixel electrode is formed; Forming a partition wall defining a unit block by sequentially forming and patterning a second metal layer and an insulating layer on the first substrate on which the color filter pattern is formed; Forming an electrophoretic material layer in a unit block defined by the partitions; And forming a second substrate on the first substrate on which the electrophoretic material and the partition wall are formed. The method of claim 5, wherein the first metal film An opaque metal film formed of any one of Al, AlNd and Ag and a transparent metal film formed of any one of ITO, IZO and ITZO are laminated. The method of claim 5, wherein the electrophoretic material layer A method for manufacturing an electrophoretic display device, characterized in that a transparent fluid containing charged black particles is filled. 6. The method of claim 5, And wherein the unit block is one unit pixel region in which the pixel electrode is formed, or a plurality of the unit blocks are the one unit pixel region. The electrophoretic display device of claim 5, wherein the passivation layer is formed of an inorganic insulating material and an organic insulating material, and the passivation layer having the data pad contact hole and the gate pad contact hole is formed of only an inorganic insulating material. Way.

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