KR101888941B1 - Display device and method of manufacturing the same - Google Patents

Abstract

The present invention relates to a display device and a method of manufacturing the same, the display device comprising: a substrate layer; A bank disposed on the base layer and having a prime area having a degree of hydrophobicity gradually changed in accordance with the opening area and the traveling direction; And a functional layer disposed on the base layer in the opening region of the bank, wherein the thin film having a uniform thickness can be formed in a predetermined region based on the wet process.

Description

DISPLAY DEVICE AND METHOD FOR MANUFACTURING THE SAME

The present invention relates to a display device and a method of manufacturing the same, and more particularly, to a display device that can be manufactured based on a wet process and a method of manufacturing the same.

Today, with the development of information communication, display devices are rapidly developing. The display device may include a plurality of conductive patterns and an insulating pattern. Particularly, the organic electroluminescent display device of the display device may include a plurality of functional layers such as an electron injecting layer, an electron transporting layer, an organic light emitting layer, a hole transporting layer, and a hole injecting layer.

In order to manufacture a display device including such a plurality of patterns and a functional layer, a thin film forming process is required. The thin film forming process can be a wet process or a dry process. The wet process has advantages in that it is easy to make it larger in comparison with the dry process, the apparatus and equipment are simple, and the production cost can be reduced. Particularly, since the wet process can be performed in a lower temperature environment than the dry process, it may be advantageous in manufacturing a flexible display device.

At present, display devices are generally structured to be manufactured based on a dry process, and development of a structure of a display device suitable for manufacturing based on a wet process and development of a technique for manufacturing the display device is required. Particularly, a wet process is a technique for forming a thin film using a solution-like material, and a technique for forming a thin film having a uniform thickness in a certain region in a wet process.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a display device capable of forming a thin film having a uniform thickness in a predetermined region based on a wet process and a method of manufacturing the same.

A display device of the solution means according to the present invention is provided. A display device according to the present invention includes a substrate layer; A bank disposed on the base layer and having a prime area having a degree of hydrophobicity gradually changed in accordance with the opening area and the traveling direction; And a functional layer disposed on the base layer of the opening region of the bank.

A manufacturing method of a display device according to still another solution according to the present invention is provided. The manufacturing method according to the present invention comprises the steps of forming a bank on a base layer having an aperture region and a prime area having a gradually changing hydrophobicity according to a traveling direction; And forming a functional layer in the opening region by a wet process.

The display device according to the embodiment of the present invention includes the bank having the hydrophobicity gradually changed according to the position, so that the thin film having excellent flatness can be formed in the region defined by the bank.

In addition, since the display device according to the embodiment of the present invention forms banks so as to have progressively changed hydrophobicity, it is possible to prevent the aperture ratio from being reduced due to the residual film as compared with the case of forming the bank with the hydrophobic material.

In addition, since the display device according to the embodiment of the present invention forms banks so as to have progressively changed hydrophobicity, it is unnecessary to consider the generation of the residual film, so that the soft baking temperature can be increased and the adhesion strength of the banks on the base layer can be increased .

In addition, the display device according to the embodiment of the present invention can adjust the taper angle of the bank by using the gray scale mask for forming the banks so as to have gradually changed hydrophobic degree, and can easily obtain the optimum taper angle .

In addition, the display device according to the embodiment of the present invention easily exposes the hydrophobic uniformity in the entire area of the display device by performing the exposure process using the gray scale mask to form banks so as to have gradually changed hydrophobicity. can do.

1 is a schematic plan view of a part of a display region of an organic light emitting display according to a first embodiment of the present invention.
2 is a circuit diagram for one pixel in Fig.
3 is a schematic cross-sectional view taken along line I-I 'of FIG.
4A to 4D are cross-sectional views illustrating various examples of the structure of a bank applicable to the embodiment of the present invention.
5A to 5E are cross-sectional views illustrating a manufacturing process of an organic light emitting display according to a second embodiment of the present invention.
6A and 6B are schematic views showing a process of forming a functional layer according to an embodiment of the present invention and a comparative example.
7 is a cross-sectional view of a liquid crystal display device according to a third embodiment of the present invention.
8 is a cross-sectional view of the color filter substrate of Fig.
9A and 9B are cross-sectional views of a bank according to an embodiment of the present invention and a comparative example.
10A and 10B are views showing pixel regions of a display device according to an embodiment and a comparative example of the present invention.
Figs. 11A and 11B are graphs of the thickness profile of the functional layer in the pixel region of the display device according to the embodiment of the present invention and the comparative example shown in Figs. 10A and 10B.
12A and 12B are top views of pixel regions of a display device according to an embodiment of the present invention and a comparative example.
13A and 13B are views for measuring the adhesion of the bank according to the embodiment and the comparative example of the present invention.
FIGS. 14A and 14B are photographs showing a state in which a hydrophilic ink is dropped onto a display device according to Examples and Comparative Examples of the present invention. FIG.

Embodiments of the present invention will be described in detail with reference to the drawings of a display device. The following embodiments are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention.

Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the size and thickness of an apparatus may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

1 is a schematic plan view of a part of a display region of an organic light emitting display according to a first embodiment of the present invention.

Referring to FIG. 1, the organic light emitting display according to the first embodiment of the present invention may include a plurality of pixels P, which are the minimum units for displaying an image.

2 is a circuit diagram for one pixel in Fig.

Referring to FIG. 2, each pixel P may be defined through a gate line GL and a data line DL disposed so as to cross each other. Here, the switching thin film transistor STr connected to the gate line GL, the driving thin film transistor DTr connected to the switching thin film transistor STr, the organic light emitting diode E connected to the driving thin film transistor DTr, May be disposed. In addition, a driving thin film transistor DTr and a storage capacitor StgC connected to the organic light emitting diode E may be further disposed in the pixel P.

Here, the switching thin film transistor STr and the driving thin film transistor DTr may include a gate electrode, a semiconductor pattern, and a source and a drain electrode, respectively. At this time, the gate electrode of the switching thin film transistor STr is electrically connected to the gate line GL, and the source electrode of the switching thin film transistor STr may be electrically connected to the data line DL. The drain electrode of the switching thin film transistor STr may be electrically connected to the gate electrode of the driving thin film transistor DTr.

Here, the source electrode of the driving thin film transistor DTr may be electrically connected to the power supply line PL. In addition, the driving thin film transistor DTr may be electrically connected to the organic light emitting diode E.

Here, the organic light emitting diode E may include an organic light emitting layer interposed between the first and second electrodes and the first and second electrodes. Here, the recombination of the first and second charges provided in each of the first and second electrodes in the organic light emitting layer is performed, and the recombined first and second charges are transited from the excited state to the ground state to generate and emit light.

At this time, the drain electrode of the driving thin film transistor DTr may be electrically connected to the first electrode of the organic light emitting diode E. At this time, the power supply line PL may be electrically connected to the second electrode of the organic light emitting diode E.

Further, the storage capacitor StgC may be formed between the gate electrode and the source electrode of the driving thin film transistor DTr.

Accordingly, the switching thin film transistor switches the driving thin film transistor in accordance with the gate signal. By switching the switching thin film transistor, the driving thin film transistor applies a current corresponding to the data signal to the organic light emitting diode. The organic light emitting diode can display the gradation according to the applied current. The storage capacitor StgC maintains the gate voltage of the driving thin film transistor DTr constant when the switching thin film transistor STr is turned off so that the level of the current flowing through the organic light emitting diode E Can be kept constant.

3 is a schematic cross-sectional view taken along line I-I 'of FIG.

3, an organic light emitting display includes an insulating member 130 disposed on a base layer 110 including a driving thin film transistor DTr and a driving thin film transistor DTr disposed on a base layer 110, , And an organic light emitting diode (E) disposed on the insulating member (130). Here, the organic light emitting display device may include a bank 150 for forming a functional layer of the organic light emitting diode E by a wet process. The bank 150 may comprise a fractional area having a gradually varying degree of hydrophobicity in at least some regions. Since the bank 150 has the prime number area, the functional layer having excellent flatness can be easily formed in a certain area by the wet process.

Specifically, an organic light emitting display device according to an embodiment of the present invention will be described.

The substrate layer 110 can be a flat substrate or a flexible film that can be bent by a constant force. Examples of the material for forming the base layer 110 may be glass, metal, or plastic.

The driving thin film transistor DTr includes a semiconductor pattern 120 disposed on the substrate layer 110, a gate insulating film 121 disposed on the substrate layer 110 including the semiconductor pattern 120, A gate electrode 122 overlapped with a partial region and disposed on the gate insulating film 121, an interlayer insulating film 123 disposed on the gate insulating film 121 including the gate electrode 122, an interlayer insulating film 123 disposed on the interlayer insulating film 123, And source and drain electrodes 124 and 125 connected to the source and drain regions of the semiconductor pattern 120, respectively. In the embodiment of the present invention, the driving thin film transistor DTr has been illustrated as having a top gate structure, but the present invention is not limited thereto. Though not shown in the figure, the switching thin film transistor may have the same shape as the driving thin film transistor DTr.

The insulating member 130 may be disposed on the base layer 110 including the driving thin film transistor DTr. Here, the insulating member 130 may have a double structure of an inorganic insulating film 131 and an organic insulating film 132. The inorganic insulating film 131 may be formed of silicon oxide or silicon nitride. In addition, the organic insulating layer 132 may perform a planarization function to remove a stepped portion by the driving thin film transistor DTr and a plurality of wirings. In the embodiment of the present invention, the insulating member 130 has a double structure, but the present invention is not limited thereto. The insulating member 130 may be formed of any one of an inorganic insulating film or an organic insulating film, It may have a triple structure of an insulating film.

The organic light emitting diode E may include a pixel electrode 140 sequentially disposed on the insulating member 130, a functional layer 160 including at least an organic light emitting layer, and a common electrode 170.

Here, the pixel electrode 140 may be connected to the drain electrode 125 through a contact hole formed in the insulating member 130.

The pixel electrode 140 may be patterned for each pixel region.

The bank 150 may cover the edge of the pixel electrode 140 and may be disposed in the non-pixel region. That is, the bank 150 includes an opening region 151 that exposes the pixel electrode 140, a side wall 152 that is disposed along the edge of the opening region 151, and a pixel electrode 140 on the edge and non- And an upper surface 153 that is disposed and connected to the sidewalls 152.

The bank 150 may serve to define a functional layer 160, particularly a formation region of an organic light emitting layer, which will be described later. In addition, the bank 150 can prevent a short circuit between the pixel electrode 140 and the common electrode 170.

The bank 150 may have a fractional area in at least some of the areas. Here, the fractional region may have gradually changed hydrophobicity as it proceeds in a certain direction. Here, the fractional area may be disposed on the side wall 152 of the bank 150. [ Accordingly, when the functional layer to be described later is formed through the wet process, not only the solution for forming the functional layer into the opening region 151 of the bank 150 flows stably, And can evenly spread in the opening area. As a result, the functional layer having excellent flatness can be formed in the opening region 151 of the bank 150.

The taper angle a of the bank 150 may range from 50 to 70 degrees. More preferably, the taper angle a of the bank 150 may range from 50 to 60 degrees. If the taper angle a of the bank 150 is less than 50, the side wall of the bank 150 is gentle and can not serve as a bank for placing the solution in a predetermined region in the wet process. On the other hand, when the taper angle (a) of the bank 150 is more than 70 degrees, it is not necessary to give a progressively changed prime degree in the wet process. This is because the solution can move well to the region defined by the bank 150 due to the sharp inclination of the side wall 152. In addition, when the taper angle a of the bank 150 is more than 70, it may be difficult to form the common electrode 170, which will be described later, with a uniform thickness due to a sharp inclination of the side wall 152. However, the taper angle a of the bank 150 is not limited in the embodiment of the present invention.

A detailed description of the bank 150 will be specifically described below.

The functional layer 160 including at least the organic light emitting layer is disposed on the pixel electrode 140 of the opening region 151 exposed by the bank 150. [

Although not shown in the drawing, in order to increase the luminous efficiency of the organic light emitting diode E, the functional layer 160 may include one or both of a hole injection layer and a hole transport layer between the pixel electrode 140 and the organic light emitting layer . The functional layer 160 may further include one or both of an electron injection layer and an electron transport layer between the organic light emitting layer and the common electrode 170.

Here, each of the hole injecting layer, the hole transporting layer, the electron injecting layer, and the electron transporting layer may be patterned for each pixel region like the organic light emitting layer. Alternatively, each of the hole injecting layer, the hole transporting layer, the electron injecting layer and the electron transporting layer may be disposed in the entire region of the display region.

The common electrode 170 may be disposed on the bank 150 including the functional layer 160.

Here, the material of the pixel electrode 140 and the common electrode 170 may be selected from a transparent conductive material or a reflective conductive material according to the emission method of the organic light emitting display. For example, when the organic electroluminescent display device is a bottom emission type in which light is emitted to the substrate layer 110, the pixel electrode 140 may be formed of a transparent conductive material and the common electrode 170 may be formed of a reflective conductive material. have. On the other hand, when the organic light emitting display device is a top emission type in which light is emitted to the common electrode 170, the pixel electrode 140 may be formed of a reflective conductive material and the common electrode may be formed of a transparent conductive material. Here, examples of the transparent conductive material include ITO or IZO. In addition, examples of the reflective conductive material may be a metal having reflective properties such as Ag or Al.

In addition, although not shown in the drawing, the organic light emitting display device may further include a sealing member bonded with the substrate layer 110 including the organic light emitting diode (E). The sealing member may seal the organic light emitting diode from the external environment to protect the organic light emitting diode (E) from external moisture and oxygen. Here, the sealing member may be an encapsulating substrate bonded on the base layer, or an inorganic protective film coated on the base layer including the organic light emitting diode (E), and does not limit the form of the encapsulating member in the embodiment of the present invention.

4A to 4D are cross-sectional views illustrating various examples of the structure of a bank applicable to the embodiment of the present invention. Here, only the base layer and the bank are shown for convenience of explanation.

Referring to FIG. 4A, the bank 150a according to the first example may have a fractional area H1 having a progressively changed degree of hydrophobicity as it proceeds in a certain direction. Here, the fractional area H1 may be formed in the entire area of the side wall 152a of the bank 150a. At this time, the degree of hydrophobicity may be increased as it goes upward from the side wall 152a of the bank 150a downward. Accordingly, when the solution is provided on the bank 150a, it can be stably moved to the opening region 151a of the bank 150a even if the solution is dropped into any region.

Referring to FIG. 4B, in the bank 150b according to the second example, the fractional area H2 may be disposed in a partial area on the side wall 152b of the bank 150b. The fractional area H2 may be the side wall 152b of the bank 150b corresponding to the formation region of the functional layer 160. [ Here, in the fractional area H2, the degree of hydrophobicity can be increased as the bank 150b moves from the lower side to the upper side. Accordingly, the fractional area of the bank 150b can be formed in only a part of the area.

Referring to FIG. 4C, in the bank 150c according to the third example, the fractional area H3 may be divided into the first and second fractional areas H3a and H3b on the sidewall. Each of the first and second fractional areas H3a and H3b may gradually increase from the lower side to the upper side of the side wall 152c of the bank 150c. At this time, the first and second fractional areas H3a and H3b may have a step difference. Thus, the taper angle of the bank 150c can be kept constant, and the step coverage of the bank 150c can be reduced, so that the common electrode formed on the bank 150c can be easily formed with a uniform thickness.

4D, when the side wall 152d of the bank 150d according to the fourth example is formed so as to have a step, the bank 150d is arranged on the lower side of the side wall 152d of the bank 150d, And a hydrophobic region having an increased degree of hydrophobicity toward the upper side.

Hereinafter, a manufacturing process of the organic light emitting display device according to the third embodiment of the present invention will be described with reference to FIGS. 5A to 5E. FIG.

5A to 5E are cross-sectional views illustrating a manufacturing process of an organic light emitting display according to a third embodiment of the present invention.

Referring to FIG. 5A, in order to manufacture an organic light emitting display, first, a thin film transistor substrate is formed.

Specifically, the semiconductor pattern 120 is formed on the base layer 110. Here, in order to form the semiconductor pattern 120, an amorphous silicon layer is first formed on the base layer through a deposition process, and then the amorphous silicon layer is crystallized. Thereafter, the semiconductor pattern 120 may be formed by patterning the crystallized amorphous silicon layer. A gate insulating film 121 is formed on the base layer 110 including the semiconductor pattern 120. The gate insulating film 121 may be formed by chemical vapor deposition. The gate insulating film 121 may be formed of silicon nitride or silicon oxide. The gate electrode 122 is formed on the gate insulating film 121 corresponding to the channel region of the semiconductor pattern 120. [ In the step of forming the gate electrode 122, a gate wiring connected to the gate electrode 122 may be formed. An interlayer insulating film 123 is formed on the gate insulating film 121 including the gate electrode 122. The interlayer insulating film 123 may be formed by chemical vapor deposition. The interlayer insulating film 123 may be formed of silicon nitride or silicon oxide. Thereafter, a via hole penetrating the interlayer insulating film 123 and the gate insulating film 121 is formed. The via hole may expose portions of both sides of the semiconductor pattern 120, that is, source and drain regions. Source and drain electrodes 124 and 125 connected to the source and drain regions of the semiconductor pattern 120 are formed on the interlayer insulating film 123 through via holes. The driving thin film transistor DTr including the semiconductor pattern 120, the gate insulating film 121, the gate electrode 122, and the source and drain electrodes 124 and 125 can be formed on the base layer 110 .

Though not shown in the drawing, a switching thin film transistor and a storage capacitor may be formed in the process of forming the driving thin film transistor DTr.

After the driving thin film transistor DTr is formed, the insulating member 130 is formed on the interlayer insulating film 123 including the driving thin film transistor DTr. Here, the insulating member 130 may be formed of a double structure of an inorganic insulating film 131 and an organic insulating film 132. At this time, the inorganic insulating film 131 may be formed by chemical vapor deposition. The inorganic insulating film 132 may be formed of silicon nitride or silicon oxide. The organic insulating film 131 may be formed through a wet process. Examples of the wet process include a spin coating method, a dip coating method, an inkjet printing method, a screen printing method, a die coating method, and a doctor blade method. Examples of the material for forming the organic insulating film 131 may include photo-acrylic resin, benzocyclobutene resin, and polyimide resin.

After forming the insulating member 130, a contact hole exposing the drain electrode 125 of the driving thin film transistor DTr is formed in the insulating member 130.

Thereafter, the pixel electrode 140 electrically connected to the drain electrode 125 is formed through the contact hole. The pixel electrode 140 may be formed by forming a conductive film and etching each pixel region.

5B, a pixel electrode 140 is formed, and then a photosensitive resin film 150L is formed on the insulating member 130 including the pixel electrode 140. Referring to FIG. The photosensitive resin film may be a negative photosensitive resin film 150L. For example, a cardo-based resin, a novolac-based resin, and an acrylic-based resin can be used for the photosensitive resin film 150L, but the material of the photosensitive resin film is not limited to the examples of the present invention. The photosensitive resin film can be formed through a wet process such as a spin coating method, a dip coating method, an inkjet printing method, a screen printing method, a die coating method, and a doctor blade method.

In order to increase the adhesion of the bank 150 to be described later, a soft baking process can be further performed. Here, in the conventional soft-baking process, there is a limit to raise the baking temperature to a residual temperature, considering that the residual film, that is, the negative photosensitive resin film, remains in the opening region. However, in the embodiment of the present invention, since the exposure amount control for preventing the generation of the residual film is easy, the temperature of the soft baking step can be made higher than the conventional one without considering the formation of the residual film. Accordingly, the adhesion force of the bank 150, which will be described later, can be increased.

Referring to FIG. 5C, an exposure process using a gray scale mask M is performed on the photosensitive resin film 150L.

In order to perform the exposure process, first, the gray scale mask M is aligned on the photosensitive resin film 150L. Here, the gray scale mask M includes a light blocking portion M1 for blocking light, a gray scale portion M2 arranged along the periphery of the light blocking portion M1, And a transmissive portion M3. The grayscale portion M2 may be a region having a progressively changed transmissivity. At this time, the light blocking portion M1 of the gray scale mask M may correspond to the opening region 151 of the bank 150. [ Here, the gray scale portion M2 may correspond to the entire region of the side wall 152 of the bank 150 or a partial region of the side wall 152. [ At this time, some regions may correspond to formation regions of the functional layer 160, which will be described later.

An exposure process is performed on the photosensitive resin film 150L including the gray scale mask M. [ Here, the exposure dose may range from 60 to 250 mJ / cm < 2 >. Preferably from 100 to 200 mJ / cm < 2 >, and more preferably from 150 to 190 mJ / cm < 2 >. Here, since the region where the light is received is cured due to the characteristics of the negative photosensitive resin film, when the exposure amount is less than 60 mJ / cm 2, a part of the bank can be removed in the developing process. On the other hand, when the exposure dose exceeds 250 mJ / cm 2, the tack time may increase. In addition, due to the diffraction of light, it is possible to deviate from the mask range, so that an area larger than the designed value is hardened, and as a result, the portion to be removed in the developing process remains, and the aperture ratio may be lowered.

Through the exposure process, the photosensitive resin film 150L in the region corresponding to the transmissive portion M3 is cured. In addition, the portion corresponding to the gray scale mask M may have a progressively changed degree of curing according to the gradual change of the light transmittance.

Thereafter, the exposed photosensitive resin film 150P is developed to form the bank 150 as shown in Fig. 5D. In the developing process, the portion corresponding to the transmissive portion M3 remains cured and the portion corresponding to the light intercepting portion M1 can be removed. Here, the sidewall 152 of the bank 150 may be formed in the boundary region between the transmissive portion M3 and the light blocking portion. At this time, the gray scale part M2 may have a reduced transmittance as it goes from the upper side of the side wall 152 to the lower side. Accordingly, a fractional area H having an increased degree of hydrophobicity may be formed in the side wall 152 of the portion corresponding to the gray scale portion M2 as the distance from the lower side to the upper side increases. This is because the crosslinking degree of the reactors having the hydrophobic property of the photosensitive resin film increases as the exposure amount increases. Accordingly, the reactors having hydrophobicity are chemically bonded in the main chain of the polymer constituting the exposed photosensitive resin film, so that the hydrophobic reactors are not removed in the developing process. That is, as the amount of exposure increases, the distribution of the hydrophobic reactors increases after the developing step. As a result, the degree of hydrophobicity of the photosensitive resin film can be increased with an increase in the exposure amount.

Here, since the degree of hydrophobicity can be controlled through the gray scale mask M, the hydrophobicity of the bank 150 in the entire region of the display device can be made uniform.

The gray scale mask M is aligned so as to correspond to the side wall 152 of the bank 150 and then the amount of exposure gradually changed in the side wall 152 of the bank 150 can be adjusted as the exposure process proceeds , The taper angle (a) of the bank 150 can be freely adjusted.

As in the embodiment of the present invention, by forming the bank 150 using the gray scale mask M, the fractional area H having gradually changed hydrophobicity in the side wall 152 of the bank 150 At the same time, a bank having an optimum taper angle (a) can be formed.

 The taper angle a of the bank 150 may be in the range of 50 to 70 degrees and more preferably the taper angle a of the bank 150 may be in the range of 50 to 60 degrees .

Further, as the bank 150 is formed using the gray scale mask M, the taper angle a can be freely adjusted. Further, the formation of the residual film of the photosensitive resin film which can remain in the opening region 151 can be controlled by the gray scale mask M. Thus, the soft baking process can be performed only taking the adhesion force of the bank 150 into account, without considering the decrease in the opening ratio due to the formation of the remaining film. That is, as in the embodiment of the present invention, by forming the bank 150 by the exposure process using the gray scale mask M, it is possible to simultaneously secure the opening ratio of the bank 150 and the adhesion force of the bank.

Referring to FIG. 5E, a solution for forming a functional layer is provided in a wet process as a formation region of the bank 150. FIG. Examples of the wet process include ink jet printing, dispensing, spin coating, slit coating, and dip coating.

The solution for forming the functional layer may have hydrophilicity. The functional layer forming solution may be a solution containing an organic light emitting material.

The functional layer forming solution may be provided in the opening area 151 of the bank 150, but may also be provided on the top surface 153 of the bank. Here, since the solution for forming a functional layer has progressively reduced hydrophobicity from the upper side to the lower side of the side wall 152 of the bank 150, the hydrophilic functional layer forming solution naturally flows into the opening of the bank 150 Area 151 as shown in FIG.

Thereafter, the functional layer forming solution disposed in the opening region 151 of the bank 150 is baked to form the functional layer 160, that is, the organic light emitting layer may be formed in the opening region 151 of the bank 150 have.

In the embodiment of the present invention, only the organic light emitting layer is formed as the functional layer 160, but the present invention is not limited thereto. For example, although not shown in the drawing, in order to increase the luminous efficiency of the organic light emitting diode E, any one of a hole injection layer and a hole transport layer may be formed as an additional functional layer 160 between the pixel electrode 140 and the organic light emitting layer Or two more. Further, one or both of the electron injecting layer and the electron transporting layer may be additionally formed as an additional functional layer between the organic light emitting layer and the common electrode 170.

Here, each of the hole injecting layer, the hole transporting layer, the electron injecting layer, and the electron transporting layer may be formed by the same method as that of the organic light emitting layer and patterned for each pixel region. Alternatively, each of the hole injection layer, the hole transport layer, the electron injection layer, and the electron transport layer may be formed by performing a wet process or a deposition process on the entire region of the display region.

Thereafter, a common electrode 170 is formed on the base layer including the functional layer 160 and the bank to form an organic layer including the pixel electrode 140, the functional layer 160, and the common electrode 170 on the base layer 110 A light emitting diode E can be formed.

In addition, although not shown in the drawing, a sealing process for sealing the organic light emitting diode E on the base layer 110 may be further performed.

Hereinafter, FIGS. 6A and 6B will specifically describe and compare the formation process of the functional layer according to the embodiment of the present invention and the comparative example.

6A and 6B are schematic views showing a process of forming a functional layer according to an embodiment of the present invention and a comparative example.

6A is a cross-sectional view illustrating a process of forming a functional layer according to an embodiment of the present invention. Here, the case where the decimal region is formed in the entire region of the sidewall of the bank is described as an example, and is not limited to the description of the present invention.

A hydrophilic functional layer forming solution 160a may be provided on the base layer 110 including the banks 150 including the sidewalls 151 of the prime number region as shown in Fig. Here, the prime number area may be a region having a progressively increased degree of hydrophobicity as it goes from the lower side of the side wall 151 of the bank 150 to the upper side. Here, the fractional area may be formed in the entire area of the bank 150. [ Here, the functional layer forming solution 160a may be disposed not only on the opening area 151 of the partition wall but also on the upper surface of the bank 150. (a1) The hydrophilic functional layer forming solution 160a is relatively hydrophilic (A2) Here, the hydrophilic functional layer forming solution 160a is formed by the hydrophobic region in the opening region (not shown) of the bank 150 151). ≪ / RTI > This is because the lower side of the sidewall 152 of the bank 150 is more hydrophilic than the upper side (a3). Thereafter, the baking process is performed to form the functional layer 160 having a uniform thickness.

FIG. 6B is a cross-sectional view illustrating a process of forming a functional layer according to a comparative example.

As in FIG. 6B, the bank 15 may include sidewalls having a constant degree of hydrophobicity or a degree of hydrophilicity. The functional layer forming solution 16a may be disposed not only in the opening region of the bank but also on the upper surface of the bank 15. (b1) The functional layer forming solution 16a is supplied to the bank 15 15). ≪ / RTI > However, the functional layer forming solution 16a forms voids V at the lower edge of the bank in moving to the opening region of the bank 15, and may not be uniformly applied. This is because the sidewall of the bank 15 has uniform hydrophobicity or hydrophilicity so that voids may occur at the point where the bank 15 and the base layer 11 meet. (B2) As the opening area of the bank 15 The functional layer forming solution 16a may remain along the path of the functional layer forming solution 16a on the side wall of the bank 15 in the course of the movement of the functional layer forming solution 16a. Thereby, the functional layer forming solution 16a can be disposed on the sidewall of the bank 15 outside the region where the functional layer forming solution 16a is formed. (B3) Thereafter, when the baking process is performed, A functional layer may be formed on the side wall of the bank 15 outside the formation region of the functional layer 15 or a pinhole may be generated in the functional layer 15 due to voids. Here, the pinhole of the functional layer 15 may cause a short failure between the pixel electrode and the common electrode disposed on both sides of the functional layer 15, respectively.

7 is a cross-sectional view of a liquid crystal display device according to a third embodiment of the present invention.

8 is a cross-sectional view of the color filter substrate of Fig.

Here, as shown in FIGS. 7 and 8, a bank having a prime number area having gradually changed hydrophobicity can be applied to a black matrix of a liquid crystal display device. Here, the bank can be modified and applied in various forms as in the first embodiment described above, except that the bank is applied to the black matrix.

6 and 7, a liquid crystal display according to an embodiment of the present invention includes a thin film transistor substrate 200 and a color filter substrate 300 facing each other and a liquid crystal layer 400 interposed between the two substrates ).

The thin film transistor substrate 200 may include a thin film transistor Tr disposed on the first substrate 210 and a pixel electrode 240 electrically connected to the thin film transistor Tr. Here, the thin film transistor substrate 200 includes a gate electrode 211 disposed on the first substrate 210, a gate insulating film 220 disposed on the gate electrode 211, a semiconductor disposed on the gate insulating film 220, A pattern 212, source and drain electrodes 214 and 215 spaced apart on the semiconductor pattern 212. The semiconductor pattern 212 may include an active layer 212a and an ohmic contact layer 212b disposed under the source and drain electrodes 214 and 215 on the active layer 212a.

The color filter substrate 300 includes a bank 320 having an opening region on the second substrate 310 and a color filter 330, a color filter 330 and a bank 320 disposed in the opening region of the bank 320, And may include a common electrode 350 disposed on the common electrode 350.

Here, the bank 320 may be formed of a material for forming a black matrix. That is, the bank 320 may be a black matrix that blocks light. The bank 320 may have a fractional area in at least some areas. Here, the fractional region may have gradually changed hydrophobicity as it proceeds in a certain direction. Here, the fractional area may be disposed on the sidewall of the bank 320. Accordingly, when the functional layer 330, that is, the color filter 330, to be described later is formed through the wet process, the solution for forming the color filter 330 stably moves within the opening region of the bank 320 A color filter 330 having a uniform thickness can be formed.

The liquid crystal layer 400 may be interposed between the TFT substrate 200 and the color filter substrate 300. Here, the liquid crystal layer 400 may be formed by laminating the thin film transistor substrate 200 and the color filter substrate 300 except for the injection region, and injecting liquid crystal into the injection region. After the formation of the liquid crystal layer 400 is completed, the injection region can be sealed. As another method for forming the liquid crystal layer 400, liquid crystal may be dropped on the thin film transistor substrate 200 or the color filter substrate 300, and then the two substrates may be bonded together to form the liquid crystal layer 400.

In the embodiment of the present invention, the pixel electrode 240 and the common electrode 350 are disposed on the TFT substrate 200 and the color filter substrate 300, respectively. However, the present invention is not limited thereto. For example, when the liquid crystal display device is of the IPS or FSS type, the pixel electrode and the common electrode may be provided on the thin film transistor substrate.

In the embodiments of the present invention, since the manufacturing process of the liquid crystal display device is well known, the method of forming the bank described in the method of manufacturing the organic light emitting display device of the second embodiment described above and the liquid crystal display device of the third embodiment A person skilled in the art will be able to refer to the structural description to sufficiently form a process for forming the bank of the liquid crystal display device, so a detailed description of the manufacturing process of the liquid crystal display device will be omitted.

Hereinafter, display devices according to Examples and Comparative Examples of the present invention were observed.

Example

In order to manufacture a display device according to an embodiment of the present invention, a thin film transistor substrate including a pixel electrode is provided. Here, the pixel electrode is formed of ITO which is a transparent conductive material. Thereafter, a bank having an opening region on the pixel electrode was formed. Here, the banks were subjected to an exposure process using a gray scale mask after applying a negative photosensitive resin film. Here, a cardo-based polymer was used as the negative photosensitive resin. Further, the gray scale mask had an increased light transmittance as it progressed from the blocking portion to the transmissive portion. At that time, the exposure amount was 200 mJ / cm 2. Thereafter, the development process was performed to form banks. The bank could have a prime area with a gradual increase in hydrophobicity as the bank progressed from the lower side to the upper side through a change in the gradual exposure amount. After that, a functional layer was formed in the opening region of the bank using a solution containing the organic luminescent material, and then a common electrode made of metal was formed on the bank including the functional layer.

Comparative Example

The display device according to the comparative example was formed through the same method as the bank according to the embodiment of the present invention, except that the exposure process using a general mask having a transmission portion and a blocking portion was performed.

Hereinafter, with reference to the drawings, a display device according to an embodiment of the present invention and a comparative example are compared and analyzed.

9A and 9B are cross-sectional views of a bank according to an embodiment of the present invention and a comparative example.

As shown in FIGS. 9A and 9B, a bank having a taper angle of about 40 DEG was formed by using a general mask, while a bank having a taper angle of about 70 DEG was formed by using a gray scale mask .

10A and 10B are views showing pixel regions of a display device according to an embodiment and a comparative example of the present invention.

10A and 10B, it has been confirmed that the pixel of the display device according to the embodiment of the present invention can form a functional layer having a uniform thickness distribution than the pixel region of the display device according to the comparative example.

Figs. 11A and 11B are graphs of the thickness profile of the functional layer in the pixel region of the display device according to the embodiment of the present invention and the comparative example shown in Figs. 10A and 10B.

11A and 11B, it can be seen that the bank of the display device according to the embodiment of the present invention has a higher taper angle than the bank of the display device according to the comparative example, and that it has a functional layer of uniform thickness .

12A and 12B are top views of pixel regions of a display device according to an embodiment of the present invention and a comparative example.

As shown in FIGS. 12A and 12B, it can be seen that the aperture ratio is improved by preventing the formation of a residual layer of the bank when using the partition wall having the fractional area, as in the embodiment of the present invention, when using the general partition wall.

13A and 13B are views for measuring the adhesion of the bank according to the embodiment and the comparative example of the present invention. Here, the pictures after forming the banks and after the tape peeling test are shown.

As shown in FIGS. 13A and 13B, since the banks according to the comparative example are removed more than the banks of the display apparatus according to the embodiment of the present invention, the banks of the display apparatus according to the embodiment of the present invention exhibit excellent adhesion .

FIGS. 14A and 14B are views showing a state in which a hydrophilic ink is dropped onto a display device according to an embodiment and a comparative example of the present invention. FIG.

14A and 14B, it was confirmed that the hydrophilic ink was uniformly applied to the pixels of the display device according to the embodiment of the present invention. However, in the display device according to the comparative example, voids were formed at the edge of the opening area of the barrier rib, That is, a phenomenon in which the hydrophilic ink is not filled can be confirmed.

Therefore, as in the embodiment of the present invention, by forming the bank having the graded degree of hydrophobicity, the functional layer having a uniform thickness can be formed by the wet process.

In addition, since the banks are manufactured using a gray scale mask, the taper angle of the banks, the aperture ratio, and the adhesion can be improved.

110: substrate layer
130: Insulation member
140, and 240:
150, 320: bank
160, 330: functional layer
170, 350: common electrode

Claims (17)

A base layer;
A bank disposed on the base layer and having a prime area having an opening area and a hydrophobic degree gradually increasing from the bottom to the top; And
And a functional layer disposed on the base layer in an opening region of the bank.
The method according to claim 1,
And the fractional area is formed in a part of a sidewall of the bank.
The method according to claim 1,
Wherein the constant fractional area is formed in the entire area of the side wall of the bank.
The method according to claim 1,
Wherein the degree of crosslinking of the hydrophobic reactor is increased by increasing the exposure amount from the lower portion of the bank to the upper portion of the bank. 5. The method of claim 4,
Wherein the fractional region has a first fractional region disposed at a lower portion of a sidewall of the bank and a second fractional region disposed at an upper portion of the bank and adjacent to the first fractional region.
6. The method of claim 5,
Wherein each of the first and second fractional regions has a gradually increasing degree of hydrophobicity as it goes from the lower portion of the sidewall of the bank to the upper portion thereof.
6. The method of claim 5,
Wherein the first and second fractional regions have a stepped structure at a side wall of the bank.
The method according to claim 1,
Wherein the functional layer includes at least an organic light emitting layer,
Further comprising a pixel electrode disposed under the functional layer and a common electrode disposed over the functional layer.
The method according to claim 1,
Wherein the functional layer comprises a color filter,
A thin film transistor substrate including a pixel electrode facing the substrate layer including the functional layer, a liquid crystal layer interposed between the substrate layer and the thin film transistor substrate, and a substrate layer including the color filter and the thin film transistor substrate And a common electrode disposed on the common electrode.
Forming a bank having an aperture region on the base layer and a prime area having a degree of hydrophobicity that progressively increases from the bottom to the top; And
And forming a functional layer in a wet process in the opening region.
11. The method of claim 10,
Wherein forming the bank comprises:
Forming a photosensitive resin film on the base layer;
Disposing a gray scale mask having a light-shielding layer corresponding to the opening area and a gray scale part corresponding to the decimal area on the photosensitive resin film;
Performing an exposure process using the gray scale mask; And
And developing the exposed photosensitive resin film to form the bank,
Wherein the amount of light irradiated increases from the lower portion of the fractional region to the upper portion due to the portion of the scales of the gray scale mask.
12. The method of claim 11,
And the gray scale portion of the gray scale mask corresponds to at least a portion of the side wall of the bank.
13. The method of claim 12,
Wherein the gray scale portion corresponds to the entire area of the side wall of the bank.
delete 11. The method of claim 10,
Wherein the wet process includes any one of an ink jet printing method, a dispensing method, a spin coating method, a slit coating method and a dip coating method.
11. The method of claim 10,
Wherein the functional layer includes an organic light emitting layer,
Forming a pixel electrode on the base layer before forming the functional layer;
And forming a common electrode on the base layer after the functional layer is formed.
11. The method of claim 10,
Wherein the functional layer comprises a color filter,
And bonding the substrate layer including the color filter and the thin film transistor substrate, and interposing a liquid crystal layer between the substrate layer and the thin film transistor substrate.

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