KR20110116506A - Electro wetting display - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to flat panel displays, and more particularly, to an electrowetting display that utilizes electrowetting properties.
A feature of the present invention is to form a color filter layer of an electrowetting display device for full color on a first substrate on which a thin film transistor, an insulating thin film, and a black oil layer are formed.
Through this, the external light incident from the outside can be blocked and absorbed by the black oil, thereby preventing the external light from being reflected by the color filter layer.
Therefore, it is not necessary to attach the anti-reflection film for external light blocking separately, thereby preventing the problem that the efficiency of transmitted light is lowered by attaching the anti-reflection film.
In particular, in the process of bonding the first and second substrates, it is not necessary to consider the bonding error of the first and second substrates, and the step of attaching the anti-reflection film can be omitted, thereby improving the efficiency of the process.

Description

Electro Wetting Display {Electro wetting display}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to flat panel displays, and more particularly, to an electrowetting display that utilizes electrowetting properties.

Until recently, cathode ray tubes (CRT) have been mainly used as display devices. Recently, however, flat panel displays such as plasma display panels (PDPs), liquid crystal display devices (LCDs), and organic luminescence emitting devices (OLEDs), which can replace CRTs, have recently been used. Devices are being widely researched and used.

In particular, as one of flat panel displays having light weight and thinness, an electrowetting display using an electrowetting characteristic has been attracting attention.

The electrical wettability characteristic is that the contact angle generated between the liquid phase and the thin film is changed by the presence or absence of electric charges at the interface. The electrowetting display device applies the electrical wettability characteristic of the polar liquid phase as an optical switching tool.

1 is a diagram schematically illustrating an electrowetting display device.

As illustrated, the electrowetting display device 10 includes first and second substrates 1 and 3 bonded to each other with the polar liquid layer 20 therebetween.

Here, a pixel region P is defined on the first substrate 1, and a thin film transistor T, which is a switching element, is formed in each pixel region P, and is connected to one electrode of the thin film transistor T. The pixel electrode 11 is formed for each pixel region P. As shown in FIG.

In addition, an insulating thin film 13 having a hydrophobic characteristic is formed on the pixel electrode 11, and a partition wall which surrounds each edge of the pixel region P is formed at a boundary of each pixel region P on the insulating thin film 13. (15) is formed.

In addition, black oil 17 is formed in each pixel area P whose edge is surrounded by the partition wall 15 and has a nonpolar characteristic and opens and closes light transmission by an applied voltage.

The common electrode 19 is entirely formed on the second substrate 3, which is the upper substrate facing the first substrate 1.

In this case, although not shown in the drawing, the electrowetting display device 10 is provided with a backlight unit for supplying light from the rear surface of the first substrate 1 so that the difference in transmittance is expressed to the outside.

Accordingly, when the electrowetting display device 10 is in a voltage off state, the non-polar black oil 17 completely covers the pixel region P, and thus, the lower portion of the first substrate 1 may be formed. Light emitted from a backlight unit (not shown) positioned at is blocked by the black oil 17 to display black.

On the other hand, when the voltage is on, an electric field is formed between the pixel electrode 11 and the common electrode 19 by the applied voltage, so that the insulating thin film 13 has a hydrophilic characteristic by the electrical wettability characteristic. .

As a result, the polar liquid layer 20 existing on the nonpolar black oil 17 pushes the black oil 17 toward the partition wall 15 to form the opening region OP in the pixel region P. FIG. Done.

Therefore, the light emitted from the backlight unit (not shown) positioned below the first substrate 1 passes through the opening area OP thereof, thereby displaying white. That is, an image is displayed.

Meanwhile, the electrowetting display device 10 includes a color filter layer (not shown) including a color filter (not shown) of red (R), green (G), and blue (B) colors on the second substrate 3. When the color filter layer (not shown) is provided on the second substrate 3, external light reflection is generated by the color filter layer 3, so that contrast is greatly reduced. There is a problem.

Therefore, in order to prevent a decrease in contrast due to external light reflection, it is common to attach an external light blocking antireflection film (not shown) such as a polarizing plate to the outside of the second substrate 3. ) Causes a problem that the efficiency of transmitted light is reduced.

In particular, by providing a color filter layer (not shown) on the second substrate 3, a probability of light leakage due to a bonding error between the first substrate 1 and the second substrate 3 on which the thin film transistor T is formed may occur. This is very high. Therefore, the first and second substrates 1 and 3 must undergo a very careful bonding process, including separate alignment processes.

Thus, the efficiency of the process is lowered.

Accordingly, an object of the present invention is to provide an electrowetting display device capable of preventing a decrease in contrast due to reflection of external light of an electrowetting display device that implements color. It is done.

In addition, the second object is to improve the efficiency of the transmitted light, and the third object is to improve the efficiency of the process.

In order to achieve the above object, the present invention includes a first substrate in which a pixel region is defined and a thin film transistor and a color filter layer are formed; A pixel electrode formed on the first substrate corresponding to the pixel region and connected to the thin film transistor; An insulating thin film having a hydrophobicity formed on the entire surface of the pixel electrode; Barrier ribs formed over the insulating thin film and covering edges of the pixel region; Non-polar black oil formed inside the partition wall on the insulating thin film; A second substrate; A common electrode formed on the second substrate to face the pixel electrode; An electrowetting display device including a polar liquid layer interposed between the first and second substrates is provided.

In this case, the color filter layer is composed of red (R), green (G), and blue (B) color filters that are sequentially repeated, and the boundary between the red (R), green (G), and blue (B) color filters. Correspondingly, the partition is formed.

The color filter layer is formed on the thin film transistor, and the color filters of red (R), green (G), and blue (B) colors each include a contact hole exposing the thin film transistor, and the pixel electrode. Is formed on the red (R), green (G), and blue (B) color filters, and is connected to the thin film transistor through the contact hole.

The color filter layer is formed under the thin film transistor, and includes a buffer layer between the thin film transistor and the color filter layer, and the black oil blocks external light reflection of the color filter layer.

In this case, the polar liquid layer is H ₂ O, and includes a backlight on the outer surface of the first substrate.

As described above, according to the present invention, by forming the color filter layer on the first substrate on which the thin film transistor, the insulating thin film and the black oil layer are formed, external light incident from the outside can be blocked and absorbed by the black oil. The external light is prevented from being reflected by the color filter layer.

Therefore, it is not necessary to attach the anti-reflection film for external light blocking separately, thereby preventing the occurrence of a problem that the efficiency of transmitted light is lowered by attaching the anti-reflection film.

In particular, in the process of bonding the first and second substrates, the bonding error of the first and second substrates does not have to be taken into consideration, and the process of attaching the anti-reflection film can be omitted, so that the efficiency of the process can be improved. have.

1 schematically illustrates an electrowetting display.
2 is a cross-sectional view of an area including a plurality of pixel areas of an electrowetting display device according to a first exemplary embodiment of the present invention.
3 is a cross-sectional view of an area including a plurality of pixel areas of an electrowetting display device according to a second exemplary embodiment of the present invention.
4A to 4B are cross-sectional views schematically showing an output mode of an electrowetting display.
5A to 5J are process charts illustrating an electrowetting display device according to a second embodiment of the present invention for each manufacturing process.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

2 is a cross-sectional view of an area including a plurality of pixel areas of an electrowetting display device according to a first exemplary embodiment of the present invention.

The electrowetting display device adopts the electrowetting property of the polar liquid phase as an optical switching tool, has a fast response speed of 10 ms or less, and achieves high color luminance of about 40%. In addition, it has a contrast ratio of about 15, and has low power consumption and high resolution characteristics of 160 dpi or less (dot per ink).

As shown in the drawing, the electrowetting display device is disposed under the panel 100 for the electrowetting display device in which the first and second substrates 101 and 103 face each other with the polar liquid layer 120 interposed therebetween. Consisting of a backlight 140.

Here, a plurality of thin film transistors T, an insulating thin film 113, a black oil 117, and a color filter layer 200 are formed on the first substrate 101, and the common electrode 119 is formed on the second substrate 103. Is formed. In addition, these two substrates 101 and 103 are sealed with a polar turn (not shown) with the polar liquid layer 120 interposed therebetween to be bonded.

In more detail, first, a plurality of gate wirings (not shown) are formed on the first substrate 101 to extend in a first direction in a display area for displaying an image, and the second direction intersects with the first direction. As a result, data wirings (not shown) defining the pixel region P together with gate wirings (not shown) are formed.

In each pixel area P, a thin film transistor T connected to these two wires (not shown) is formed at a portion where a gate wiring (not shown) and a data wiring (not shown) intersect, and a thin film transistor (T) is formed. ) Is formed of a gate electrode 121, a gate insulating film 123, a semiconductor layer 125, and source and drain electrodes 127 and 129.

Here, the semiconductor layer 125 is composed of an active layer 125a made of pure amorphous silicon (a-si: H) and an ohmic contact layer 125b made of amorphous silicon (n + a-si: H) containing impurities. The gate electrode 121 is connected to a gate wiring (not shown), and the source electrode 127 is connected to a data wiring (not shown).

In addition, a passivation layer 131 having a first contact hole 131a exposing a part of the drain electrode 129 of each thin film transistor T is formed on the passivation layer 131. The color filters 210a, 210b, and 210c of red (R), green (G), and blue (B) colors are respectively formed in each pixel area.

At this time, the color filters 210a, 210b, and 210c of red (R), green (G), and blue (B) colors have a boundary of each pixel region (P), more precisely, gate and data wiring (not shown) and a thin film. Red (R), green (G), and blue (B) color filters 210a, 210b, and 210c are formed in a region corresponding to the transistor T so as to be positioned.

The red (R), green (G), and blue (B) color filters 210a, 210b, and 210c form a color filter layer 200, and the arrangement of each color layer may be variously modified.

Accordingly, the electrowetting display device of the present invention emits R, G, and B colors for each pixel area P, thereby realizing full color through mixing of light.

At this time, each of the red (R), green (G), and blue (B) color filters 210a, 210b, and 210c is part of the drain electrode 129 of the thin film transistor T of each pixel region P. Is formed to have a second contact hole 200a exposing the light emitting layer, and the thin film transistor T is disposed on the color filter layer 200 through the first and second contact holes 131a and 200a for each pixel area P. The pixel electrode 133 in contact with the drain electrode 129 is formed.

In addition, an insulating thin film 113 is formed by coating or depositing a material having a hydrophobic property on the pixel electrode 133, and the insulating thin film 113 is formed of a polymer of a series such as teflon.

On the insulating thin film 113, a partition wall 115 is formed on the boundary of each pixel region to surround the edge of each pixel region P. That is, the partition wall 115 is formed in a lattice shape in plan view corresponding to the gate and data wirings (not shown). Accordingly, the partition wall 115 has gate and data wirings (not shown) defining each pixel area P. FIG. )).

The partition wall 115 is formed of a photoresist or the like.

The black oil 117 which opens and closes light transmission by a voltage applied to the inside of the partition wall 115, which is a predetermined space defined by the partition wall 115 for each pixel region P. FIG. This is filled.

The black oil 117 is an organic solvent such as silicon oil, mineral oil, carbon tetrachloride (CCl ₄ ), which is black, and has a nonpolar characteristic.

In particular, the black oil 117 of the present invention blocks and absorbs external light incident from the outside in addition to shielding the transmission of light, thereby preventing the external light from being reflected.

In more detail, in the display device, in addition to the light emitted from the backlight unit 140, a specific light is incident from the outside into the display device, and the incident external light is reflected by the color filter layer 200 to display the display device. This will greatly reduce the contrast.

Therefore, in order to prevent the external light from being reflected by the color filter layer 200, a separate anti-reflection film (not shown) is attached to the side on which the external light is incident, that is, the outside of the second substrate 103. It must block itself from being incident on the color filter layer 200.

However, in the electrowetting display device of the present invention, as the color filter layer 200 is formed on the first substrate 101, the black oil 117 is positioned on the color filter layer 200. Therefore, the external light incident from the outside is to block the incident to the color filter layer 200 by the black oil 117.

That is, the black oil 117 replaces the role of the existing anti-reflection film (not shown) for blocking external light.

Therefore, the present invention can prevent the external light from being reflected and reducing the contrast.

In particular, the external light blocking antireflection film (not shown) does not need to be separately attached, thereby preventing the efficiency of transmitted light from being lowered by attaching the antireflection film (not shown), and attaching the antireflection film (not shown). May be omitted to improve the efficiency of the process.

The common electrode 119 is entirely formed on the second substrate 103 facing the first substrate 101 as a transparent conductive material for forming an electric field with the pixel electrode 133 formed on the first substrate 101. It is composed.

Between the first and second substrates 101 and 103 having such a configuration, a polar liquid layer 120 is interposed between a liquid having a polarity characteristic, and although not shown, to prevent leakage of the polar liquid layer 120. A seal pattern is formed along the edges of both substrates 101 and 103.

At this time, the liquid having a polar characteristic may be made of H ₂ O as an example. Therefore, the polar liquid layer 120 and the black oil 117 have different specific gravity and form a boundary without being mixed with each other.

Therefore, the signal for turning on / off the thin film transistor T is sequentially scanned and applied to the gate wiring (not shown), so that the image signal of the data wiring (not shown) is selected and the pixel region P is selected. The black oil 117 filled in each pixel region P by an electric field between the pixel electrode 133 and the common electrode 119 is transferred to the pixel electrode 133 of the pixel electrode 133 and the common electrode 119. In response to the potential difference applied to), it is scattered or aggregated to display an image.

In addition, the backlight 140 is configured to supply light from the rear surface of the electrowetting display panel 100 so that the difference in transmittance of the electrowetting display panel 100 is expressed to the outside.

The backlight 140 is classified into a side type and a direct type according to a position of a light source (not shown) that emits light, and the backlight 140 has a rear side thereof with respect to the panel 100 for an electrowetting display device. The light of a light source (not shown) emitted from one side of the light is refracted by a separate light guide plate (not shown) to be incident on the panel 100 for the electrowetting display, and the direct type is the back of the panel 100 for the electrowetting display. Thus, a plurality of light sources (not shown) are directly arranged to cause light to enter.

The present invention can use either of them.

In this case, as a light source (not shown), a fluorescent lamp such as a cold cathode fluorescent lamp or an external electrode fluorescent lamp may be used. Alternatively, a light emitting diode lamp may be used as the lamp in addition to the fluorescent lamp.

In the present invention, the color filter layer 200 is formed on the first substrate 101 on which the thin film transistor T, the insulating thin film 113, and the black oil 117 are formed. 117 may be blocked and absorbed to prevent external light from being reflected by the color filter layer 200.

Therefore, the external light blocking antireflection film (not shown) does not need to be separately attached, thereby preventing the problem that the efficiency of transmitted light is lowered by attaching the antireflection film (not shown).

In particular, in the process of bonding the first and second substrates 101 and 103, the bonding error of the first and second substrates 101 and 103 does not have to be considered, and the process of attaching the anti-reflection film (not shown) is omitted. Can improve the efficiency of the process.

On the other hand, the color filter layer 200 of the electrowetting display device of the present invention can be configured to be positioned on the thin film transistor (T).

3 is a cross-sectional view of an area including a plurality of pixel areas of an electrowetting display device according to a second exemplary embodiment of the present invention.

Here, in order to avoid duplicate description with the above-described first embodiment, the same reference numerals are given to the same parts, which play the same role as the above description, and only the characteristic contents will be described.

As illustrated, a plurality of thin films are formed on the first substrate 101 of the panel 100 for the electrowetting display device, in which the first and second substrates 101 and 103 face to face with the polar liquid layer 120 interposed therebetween. The transistor T, the insulating thin film 113, the black oil 117, and the color filter layer 200 are formed. In this case, the color filter layer 200 is formed on the thin film transistor T.

In detail, first, as an example of sequentially repeating each pixel region P defined on the first substrate 101, R (red), G (green), and B (blue) color filters 210a and 210b. , 210c) is configured.

The red (R), green (G), and blue (B) color filters 210a, 210b, and 210c form a color filter layer 200, and the arrangement of each color layer may be variously modified.

Accordingly, the electrowetting display device of the present invention emits R, G, and B colors for each pixel area P, thereby realizing full color through mixing of light.

The buffer layer 220 is formed of a transparent organic insulating material on the color filters 210a, 210b, and 210c of red (R), green (G), and blue (B) colors.

The buffer layer 220 removes the step of the color filter layer 200 and protects the color filter layer 200.

In the display area for displaying an image, a plurality of gate wirings (not shown) are formed on the buffer layer 220, and gate wirings (not shown) extend in a second direction crossing the first direction. In addition, data wiring (not shown) defining the pixel region P is formed.

In each pixel region P, a thin film transistor T connected to the two wires is formed at a portion where a gate wiring (not shown) and a data wiring (not shown) intersect, and the thin film transistor T is a gate electrode. (121), the gate insulating film 123, the semiconductor layer 125, and the source and drain electrodes 127 and 129.

The semiconductor layer 125 includes an active layer 125a made of pure amorphous silicon (a-si: H) and an ohmic contact layer 125b made of amorphous silicon (n + a-si: H) containing impurities.

In this case, the gate electrode 121 is connected to the gate wiring (not shown), and the source electrode 127 is connected to the data wiring (not shown).

In addition, a passivation layer 131 having a contact hole 131a exposing a part of the drain electrode 129 of each of the thin film transistors T is formed on the thin film transistor T. In each pixel region P, a pixel electrode 133 is formed to contact the drain electrode 129 of each thin film transistor T through the contact hole 131a.

In addition, an insulating thin film 113 is formed on the pixel electrode 133 by coating or depositing a material having a hydrophobic characteristic on the entire surface of the pixel electrode 133. A partition wall 115 covering the edge of P is formed.

That is, the partition wall 115 is formed in a lattice shape in plan view corresponding to the gate and data wirings (not shown). Accordingly, the partition wall 115 has gate and data wirings (not shown) defining each pixel area P. FIG. )).

The partition wall 115 is formed of a photoresist or the like.

The black oil 117 which opens and closes light transmission by a voltage applied to the inside of the partition wall 115, which is a predetermined space defined by the partition wall 115 for each pixel region P. FIG. This is filled.

The black oil 117 is an organic solvent such as silicon oil, mineral oil, carbon tetrachloride (CCl ₄ ), which is black, and has a nonpolar characteristic.

In particular, the black oil 117 of the present invention blocks and absorbs external light incident from the outside in addition to shielding the transmission of light, thereby preventing the external light from being reflected.

That is, the black oil 117 replaces the role of the existing anti-reflection film (not shown) for blocking external light. Therefore, the present invention can prevent the external light from being reflected and reducing the contrast.

In particular, the external light blocking antireflection film (not shown) does not need to be separately attached, thereby preventing the efficiency of transmitted light from being lowered by attaching the antireflection film (not shown), and attaching the antireflection film (not shown). May be omitted to improve the efficiency of the process.

The common electrode 119 is entirely formed on the second substrate 103 facing the first substrate 101 as a transparent conductive material for forming an electric field with the pixel electrode 133 formed on the first substrate 101. It is composed.

Between the first and second substrates 101 and 103 having such a configuration, a polar liquid layer 120 is interposed between a liquid having a polarity characteristic, and although not shown, to prevent leakage of the polar liquid layer 120. A seal pattern is formed along the edges of both substrates 101 and 103.

At this time, the liquid having a polar characteristic may be made of H ₂ O as an example. Therefore, the polar liquid layer 120 and the black oil 117 have different specific gravity and form a boundary without being mixed with each other.

Therefore, the signal for turning on / off the thin film transistor T is sequentially scanned and applied to the gate wiring (not shown), so that the image signal of the data wiring (not shown) is selected and the pixel region P is selected. The black oil 117 filled in each pixel region P by an electric field between the pixel electrode 133 and the common electrode 119 is transferred to the pixel electrode 133 of the pixel electrode 133 and the common electrode 119. In response to the potential difference applied to), it is scattered or aggregated to display an image.

The electrowetting display device according to the second embodiment of the present invention can be formed with a simple configuration in the color filter layer 200 without the formation of a separate contact hole 200a compared to the first embodiment, thereby simplifying the manufacturing process. have.

4A to 4B are cross-sectional views schematically illustrating an output mode of an electrowetting display device.

In this case, the green pixel region will be described as an example.

As shown in FIG. 4A, when the thin film transistor T of the green pixel region P is selectively controlled and a signal voltage is applied to the pixel electrode 133, between the pixel electrode 133 and the common electrode 119. An electric field having a specific intensity is formed in the insulating film, and the insulating thin film 113 is changed to hydrophilic by the electric field having the specific intensity.

As a result, the polar liquid layer 120 pushes the black oil 117 toward the side surface of the pixel region P, that is, the partition wall 115, to form the opening region OP.

Accordingly, light emitted from the backlight unit 140 positioned below the first substrate 101 passes through the opening area OP through the green color filter 200b, thereby expressing green color.

In this case, the area where the polar liquid layer 120 comes into contact with the insulating thin film 113 varies according to the intensity of the electric field applied between the common electrode 119 and the pixel electrode 133. That is, since the area in the pixel region P covered by the black oil 117 is formed differently, the amount of light transmitted can be adjusted.

Therefore, the gray level can be changed while passing through the same color filter layer (200 of FIG. 3) for each pixel region P. FIG.

In addition, as shown in FIG. 4B, when the voltage is not applied to the pixel electrode 133 to maintain the off state, the insulating thin film 113 has a hydrophobic property, and thus the polar liquid layer 120 It is located on top of the black oil 117.

Accordingly, since the black oil 117 spreads thinly over the entire green pixel region P surrounded by the partition wall 115 and covers the entire pixel region P, the light emitted from the backlight unit 140 is black oil 117. Blocked by the light, the pixel region P cannot be transmitted, thereby displaying black.

Hereinafter, a method of manufacturing an electrowetting display device according to a second embodiment of the present invention will be described with reference to FIGS. 5A to 5J.

Here, the electrowetting display device according to the second embodiment of the present invention is characterized in that the color filter layer 200 is formed on the first substrate 101. Therefore, the manufacturing method of the first substrate 101 will be described. I'll do it.

First, as shown in FIG. 5A, one of red (R), green (G), and blue (B), for example, red (R) pigments is spin coated on the substrate 101. The red (R) color filter material layer 210 is formed by coating the entire surface through a coating method or a bar coating method.

Thus, after forming the red (R) color filter material layer 210 on the first substrate 101, a mask (not shown) having a transmission region for passing light and a blocking region for blocking light, is formed on the first substrate. The red (R) color filter 210a is repeated at regular intervals as shown in FIG. 5B by exposing and developing the red (R) color filter material layer 210 after being positioned on the 101. Will form.

Next, as shown in FIG. 5C, the process proceeds in the same manner as the method of forming the red color filter 210a, and the green (G) and blue (B) pigments are applied, exposed, and developed, respectively. (G) and blue (B) color filters 210b and 210c are formed on the first substrate 101.

Accordingly, the color filter layer 200 is formed on the first substrate 101 by sequentially repeating the red, green, and blue color filters 210a, 210b, and 210c.

Next, as shown in FIG. 5D, the protection of the color filters 210a, 210b, and 210c on the red (R), green (G), and blue (B) color filters (210a, 210b, and 210c) is performed. The buffer layer 220 is formed by applying a transparent organic insulating material to compensate for the step difference.

Thereafter, as shown in FIG. 5E, a thin film transistor T is formed on the buffer layer 220. The thin film transistor T is a color filter of red (R), green (G), and blue (B) colors. It forms in correspondence with the boundary of 210a, 210b, 210c.

That is, the thin film transistor T includes the gate electrode 121, the semiconductor layer 125, and the source and drain electrodes 127 and 129. Although not shown in the drawings, the formation method thereof will be described in detail. A first metal layer is formed and patterned on the substrate 101 to form a gate wiring (not shown) and a gate electrode 121.

In this case, the gate wirings (not shown) are formed corresponding to the boundaries of the color filters 210a, 210b, and 210c of red (R), green (G), and blue (B) colors.

The first metal layer is formed by selecting one of a conductive metal group consisting of aluminum (Al), aluminum alloy, copper (Cu), tungsten (W), molybdenum (Mo), and chromium (Cr).

Next, silicon nitride (SiNx) or silicon oxide (SiO 2) is deposited on the entire surface of the substrate 101 to form a gate insulating film 123, and then on the gate insulating film 123 on the gate electrode 121. A semiconductor layer 125 comprising a source layer and a drain including an active layer 125a formed of pure amorphous silicon (a-Si: H) and an ohmic contact layer 125b formed of impurity amorphous silicon (n + a-Si: H). Electrodes 127 and 129 are formed.

At this time, in the process of forming the source and drain electrodes 127 and 129, a data line (not shown) intersecting with the gate line (not shown) and the common line (not shown) is formed. The data line (not shown) It is connected to the electrode 127.

Here, the data line (not shown) is also formed corresponding to the boundary of the color filters 210a, 210b, and 210c of red (R), green (G), and blue (B) colors. Accordingly, each of the red, green, and blue color filters 210a, 210b, and 210c define pixels in which the gate line (not shown) and the data line (not shown) cross each other. It is located in the area P, respectively.

Next, as shown in FIG. 5F, the protective layer 131 is formed by sequentially applying an insulating material and an inorganic material to the entire surface of the substrate 101 on which the source and drain electrodes 127 and 129 are formed. As a result, a contact hole 131a exposing a part of the drain electrode 129 is formed.

Next, as illustrated in FIG. 5G, the transparent conductive material is deposited on the protective layer 131 and patterned to form the pixel electrode 133 in contact with the drain electrode 129 through the contact hole 131a. do.

Next, as shown in FIG. 5H, the insulating thin film 113 is formed by depositing or applying a hydrophobic material such as teflon on the entire surface of the pixel electrode 133 to the entire surface, and then continuously insulating thin film. The organic insulating material is coated over the pattern 113 and patterned to form a grid partition wall 115 corresponding to a gate and data wiring (not shown), as shown in FIG. 5I.

Next, as illustrated in FIG. 5J, the non-polar black oil 117 is applied to each pixel region P surrounded by the partition wall 115 to provide an electrowetting display device according to the first embodiment of the present invention. The first substrate 101 is completed.

Thereafter, a seal pattern (not shown) is formed along edges of the first and second substrates 101 (103 of FIG. 3), and referring to FIG. 3, the second substrate 103 having the common electrode 119 formed on the entire surface thereof. ) To face the first substrate 101 and to be bonded to each other to form a panel state, and the polar liquid layer 120 is injected into the spaced areas of the two substrates (101, 103), according to the second embodiment of the present invention The electrowetting display is completed.

As described above, in the electrowetting display device of the present invention, the color filter layer 200 is formed on the first substrate 101 on which the thin film transistor T, the insulating thin film 113, and the black oil 117 are formed. The external light incident from the block may be blocked and absorbed by the black oil 117, thereby preventing the external light from being reflected by the color filter layer 200.

Therefore, the external light blocking antireflection film (not shown) does not need to be separately attached, thereby preventing the problem that the efficiency of transmitted light is lowered by attaching the antireflection film (not shown).

In particular, in the process of bonding the first and second substrates 101 and 103, the bonding error of the first and second substrates 101 and 103 does not have to be considered, and the process of attaching the anti-reflection film (not shown) is omitted. Can improve the efficiency of the process.

Meanwhile, in the above description, the electrowetting display device has a backlight (140 in FIG. 3) positioned under the electrowetting display panel (100 in FIG. 3), and thus the panel for the electrowetting display device (100 in FIG. 3). ), But the transmission type (transmission type) in which the difference in transmittance is expressed to the outside by supplying light to the outside has been described as an example, but the electrowetting display device of the present invention reflects the pixel electrode (133 of FIG. 3) such as aluminum (Al). The reflection type is formed of a metal, and the external light incident from the outside of the second substrate (103 in Fig. 3) is reflected by the pixel electrode (133 in Fig. 3) to implement the image through the reflected light (reflection type) It is possible.

Alternatively, a transflective type electrowetting display device that accommodates only the advantages of reflective and transmissive is also possible.

The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

100: panel for electrowetting display
101: first substrate, 103: second substrate, 113: insulating thin film, 115: partition wall
117: black oil, 119: common electrode, 120: polar liquid layer
121: gate electrode, 123: gate insulating film
125: semiconductor layer (125a: active layer, 125b: ohmic contact layer)
127: source electrode, 129: drain electrode, 131: protective layer, 131a: contact hole
133: pixel electrode
200: color filter layer, 210a, 210b, 210c: red (R), green (G), blue (B) color filter
220: buffer layer, T: thin film transistor, P: pixel region

Claims (9)

A first substrate having a pixel region defined therein, and having a thin film transistor and a color filter layer formed thereon;
A pixel electrode formed on the first substrate corresponding to the pixel region and connected to the thin film transistor;
An insulating thin film having a hydrophobicity formed on the entire surface of the pixel electrode;
Barrier ribs formed over the insulating thin film and covering edges of the pixel region;
Non-polar black oil formed inside the partition wall on the insulating thin film;
A second substrate;
A common electrode formed on the second substrate to face the pixel electrode;
A polar liquid layer interposed between the first and second substrates
Electro wetting display device comprising a.
The method of claim 1,
The color filter layer is an electrowetting display device consisting of red (R), green (G), blue (B) color filters sequentially repeated.
The method of claim 2,
An electrowetting display device in which the partition wall is formed corresponding to a boundary of the red (R), green (G), and blue (B) color filters.
The method of claim 2,
The color filter layer is formed on the thin film transistor, and the red (R), green (G), and blue (B) color filters each include a contact hole exposing the thin film transistor.
The method of claim 4, wherein
The pixel electrode is formed on top of the red (R), green (G), and blue (B) color filters, and is connected to the thin film transistor through the contact hole.
The method of claim 1,
The color filter layer is formed under the thin film transistor, and includes a buffer layer between the thin film transistor and the color filter layer.
The method of claim 1,
And the black oil blocks an external light reflection of the color filter layer.
The method of claim 1,
And the polar liquid layer is H ₂ O. ₂ .
The method of claim 1,
And an backlight on an outer surface of the first substrate.

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