KR102660313B1 - Electroluminescent Display Device - Google Patents

Abstract

The present invention includes a pixel electrode provided for each pixel; a thin film transistor electrically connected to the pixel electrode; and a bank layer having an open area for exposing a portion of the pixel electrode to define a light-emitting area, wherein the pixel electrode is electrically connected to an electrode portion provided in the light-emitting area and the thin film transistor. An electroluminescent display device comprising a contact part and a connection part connecting the electrode part and the contact part, wherein the bank layer is provided with a crack prevention part at a position facing the connection part,
According to the present invention, since the bank layer is provided with a crack prevention portion, even if an alignment process error of the bank layer occurs, the connection portion of the pixel electrode can overlap with the crack prevention portion, thereby preventing cracks from occurring in the connection portion. It can be.

Description

Electroluminescent Display Device

The present invention relates to an electroluminescence display device, and more specifically, to a bank layer of an electroluminescence display device.

An electroluminescent display device is a device that has a structure in which a light-emitting layer is formed between two electrodes, and displays an image by causing the light-emitting layer to emit light due to an electric field between the two electrodes.

The light-emitting layer may be made of an organic material that generates excitons by combining electrons and holes and emits light as the generated excitons fall from the excited state to the ground state, and may be made of quantum dots. It may be made of inorganic materials such as dots.

Hereinafter, a conventional electroluminescent display device will be described with reference to the drawings.

1A and 1B are schematic plan views of a conventional electroluminescent display device.

As can be seen in FIGS. 1A and 1B, a conventional electroluminescent display device includes a gate line (GL), a data line (DL), a power line (VDD), a pixel electrode (PE), a thin film transistor (TFT), and a bank layer. (BL) is included.

Such an electroluminescent display device includes a light emitting area (EA) that emits light and a circuit area (CA) that controls light emission of the light emitting area. The light emitting area (EA) and the circuit area (CA) are composed of a plurality of pixels. The pixel electrode (PE) is disposed in the emission area (EA), and the thin film transistor (TFT) is disposed in the circuit area (CA).

The gate line (GL) is arranged in the horizontal direction, and the data line (DL) and the power line (VDD) are arranged in the vertical direction. The gate line (GL), the data line (DL), and A pixel may be defined by a power line (VDD).

The pixel electrode (PE) is patterned for each of the plurality of pixels and is electrically connected to the thin film transistor (TFT).

The thin film transistor (TFT) includes a switching thin film transistor, a driving thin film transistor, and a sensing thin film transistor, of which the driving thin film transistor is electrically connected to the pixel electrode (PE).

The bank layer BL is patterned to define the light emitting area EA. Specifically, the bank layer BL is patterned to overlap the gate line GL, the data line DL, and the power line VDD, and is patterned to overlap the entire circuit area CA. do. Additionally, the bank layer BL is patterned to overlap the edge of the pixel electrode PE. For reference, for convenience, the bank layer BL is indicated by hatching in the drawing.

Meanwhile, although not shown, a light-emitting layer is formed on the pixel electrode PE, and a counter electrode is formed on the light-emitting layer. In this case, the pixel electrode (PE) may function as an anode and the counter electrode may function as a cathode.

In the case of such a conventional electroluminescent display device, there is a problem in which cracks occur in the pixel electrode (PE) when an error occurs in the pattern alignment of the bank layer (BL). This will be described in detail as follows. same.

As shown in FIG. 1A, the bank layer BL is patterned to overlap the edge of the pixel electrode PE. When the bank layer BL is patterned to overlap the top, left and right sides, and bottom of the pixel electrode PE, no cracks occur in the pixel electrode PE.

However, as shown in FIG. 1B, an error may occur in the mask alignment process when forming the bank layer BL, and the entire bank layer BL may be pushed downward to form a pattern. In this case, the bank layer BL overlaps the upper side and the left and right sides of the pixel electrode PE, but does not overlap the lower side of the pixel electrode PE. In this way, when the bank layer (BL) is patterned so as not to overlap the lower side of the pixel electrode (PE), the pixel electrode (PE) is extended and has a narrow width so as to be connected to the thin film transistor (TFT). One part (PE1) is covered by the bank layer (BL), but the other part (PE2) of the pixel electrode (PE) is not covered by the bank layer (BL). In this case, when the bank layer BL expands and contracts during the process, cracks may occur in other parts PE2 of the pixel electrode PE that are not covered by the bank layer BL. In this way, if a crack occurs in the pixel electrode (PE), signal transmission is interrupted, light is not emitted smoothly in the light emitting area (EA), and dark spot defects may occur.

The present invention was designed to solve the above-described conventional problems, and the present invention provides an electroluminescent display device that can prevent cracks from occurring in the pixel electrode even if expansion and contraction occur in the bank layer during the process. The purpose is to

In order to achieve the above object, the present invention includes a pixel electrode provided for each pixel; a thin film transistor electrically connected to the pixel electrode; and a bank layer having an open area for exposing a portion of the pixel electrode to define a light-emitting area, wherein the pixel electrode is electrically connected to an electrode portion provided in the light-emitting area and the thin film transistor. An electroluminescent display device includes a contact portion and a connection portion connecting the electrode portion and the contact portion, and the bank layer is provided with a crack prevention portion at a position facing the connection portion.

The present invention also provides a pixel electrode including an electrode portion provided in a light emitting area, a contact portion electrically connected to a thin film transistor, and a connection portion connecting the electrode portion and the contact portion; and a bank layer provided to overlap the edge of the electrode portion while exposing the central portion of the electrode portion, wherein the bank layer is provided with a crack prevention portion protruding into the inner region of the electrode portion at a position facing the connection portion. An electroluminescent display device is provided.

The present invention also provides a pixel electrode including an electrode portion provided in a light emitting area, a contact portion electrically connected to a thin film transistor, and a connection portion connecting the electrode portion and the contact portion; and a bank layer provided to overlap at least a portion of an edge of the electrode portion, wherein the bank layer is provided with a crack prevention portion protruding into an inner region of the electrode portion at a position facing the connection portion, and the crack prevention portion is provided. An electroluminescent display device is provided so that at least a portion of the portion overlaps the connection portion.

According to the present invention as described above, the following effects are achieved.

According to the present invention, since the bank layer is provided with a crack prevention portion, even if an alignment process error of the bank layer occurs, the connection portion of the pixel electrode can overlap with the crack prevention portion, thereby preventing cracks from occurring in the connection portion. It can be.

1A and 1B are schematic plan views of a conventional electroluminescent display device.
Figure 2 is a schematic diagram of an electroluminescence display device according to an embodiment of the present invention.
FIGS. 3A to 3C are schematic plan views of one pixel constituting an electroluminescent display device according to an embodiment of the present invention. FIGS. 3A and 3B show the bank layer being patterned without alignment errors. , Figure 3c shows an alignment error occurring in the bank layer.
FIG. 4A is a schematic plan view showing a crack prevention portion of the bank layer according to an embodiment of the present invention, and FIG. 4B is a cross-section of the AB line and CD line of FIG. 4A. An electroluminescent display device according to an embodiment of the present invention. This is a cross-sectional view of .
5 to 8 are schematic plan views showing crack prevention portions of the bank layer according to various embodiments of the present invention.
9 to 11 are schematic plan views showing pixel electrodes and bank layers according to various embodiments of the present invention.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and will be implemented in various different forms. These embodiments only serve to ensure that the disclosure of the present invention is complete and that common knowledge in the technical field to which the present invention pertains is not limited. It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining embodiments of the present invention are illustrative, and the present invention is not limited to the matters shown. Like reference numerals refer to like elements throughout the specification. Additionally, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. When 'includes', 'has', 'consists of', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the plural is included unless specifically stated otherwise.

When interpreting a component, it is interpreted to include the margin of error even if there is no separate explicit description.

In the case of a description of a positional relationship, for example, if the positional relationship of two parts is described as 'on top', 'on the top', 'on the bottom', 'next to', etc., 'immediately' Alternatively, there may be one or more other parts placed between the two parts, unless 'directly' is used.

In the case of a description of a temporal relationship, for example, if a temporal relationship is described as 'after', 'successfully after', 'after', 'before', etc., 'immediately' or 'directly' Unless used, non-consecutive cases may also be included.

Although first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are merely used to distinguish one component from another. Accordingly, the first component mentioned below may also be the second component within the technical spirit of the present invention.

Each feature of the various embodiments of the present invention can be combined or combined with each other partially or entirely, and various technical interconnections and operations are possible, and each embodiment can be implemented independently of each other or together in a related relationship. It may be possible.

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

Figure 2 is a schematic diagram of an electroluminescence display device according to an embodiment of the present invention.

As can be seen in FIG. 2, the electroluminescent display device according to an embodiment of the present invention includes a gate line (GL), a sensing line (SL), data lines (DL1, DL2, DL3, DL4), a power line (VDD), and reference lines (Ref1, Ref2).

The electroluminescent display device according to an embodiment of the present invention includes a light emitting area (EA) that emits light and a circuit area (CA) that controls light emission of the light emitting area. The light emitting area (EA) and the circuit area (CA) are composed of a plurality of pixels.

A pixel electrode, a light-emitting layer, and a counter electrode are formed in the light-emitting area EA. An electric field is generated between the pixel electrode and the counter electrode, and the light-emitting layer emits light due to the electric field.

A switching thin film transistor, a driving thin film transistor, a sensing thin film transistor, and a capacitor are formed in the circuit area CA to control light emission of the light emitting area EA.

The switching thin film transistor is switched according to the gate signal supplied to the gate line GL and supplies the data voltage supplied from the data lines DL1, DL2, DL3, and DL4 to the driving thin film transistor. The driving thin film transistor is switched according to the data voltage supplied from the switching thin film transistor to generate a data current from the power supplied from the power line (VDD) and supplies it to the pixel electrode of the light emitting area (EA). The sensing thin film transistor is for sensing a threshold voltage deviation of the driving thin film transistor, which causes deterioration of image quality, and controls the current of the driving thin film transistor in response to a sensing control signal supplied from the sensing line (SL) to the reference line. Supplied as (Ref1, Ref2). The capacitor maintains the data voltage supplied to the driving thin film transistor for one frame. The circuit area CA may be formed in various forms known in the art.

In Figure 2, the leftmost red light emitting area (EA(R)) and the rightmost white light emitting area (EA(W)) are connected to the gate line GL, the reference lines Ref1, Ref2, and the data line ( It is provided by a combination including DL1 and DL4), and the green light-emitting area (EA(G)) and the blue light-emitting area (EA(B)) at the center are connected to the gate line (GL), the power line (VDD), and the data lines DL2 and DL3, but is not necessarily limited thereto.

For example, as shown, four pixels from columns 1 to 4 are displayed using two reference lines (Ref1, Ref2), four data lines (DL1, DL4), and one power line (VDD). may be configured, but is not necessarily limited thereto, and it is also possible to configure one power line, one reference line, and one data line for each pixel. In addition, the arrangement of the red light-emitting area (EA(R)), green light-emitting area (EA(G)), blue light-emitting area (EA(B)), and white light-emitting area (EA(W)) may also be changed in various ways. You can.

Although FIG. 2 shows the circuit area CA provided between the gate line GL and the sensing line SL, the circuit area CA is not necessarily limited thereto.

For example, the gate line (GL) may be disposed between the sensing line (SL) and the circuit area (CA), in which case the circuit area (CA) is connected to the light emitting area (EA) and the gate. It is provided between lines (CA). Additionally, the sensing line (SL) may be omitted and the gate line (GL) may also be configured to perform the function of the sensing line (SL).

Additionally, the electroluminescent display device according to the present invention may be configured with a top emission structure in which light emitted from the light emitting area EA is emitted toward the top, and light emitted from the light emitting area EA is emitted toward the bottom. It may also have a bottom emission structure that emits light toward the side.

In FIG. 2 , the circuit area CA and the light emitting area EA are shown not to overlap each other, but the present invention is not limited thereto. In terms of cross-sectional structure, the circuit area (CA) may be formed below the light-emitting area (EA), and in the case of the lower light-emitting structure, the circuit area (CA) and the light-emitting area (EA) may not overlap each other. It is preferable that the upper light emitting structure be formed, and in the case of the upper light emitting structure, the circuit area CA and the light emitting area EA may overlap each other. Specifically, in the case of the lower light emitting structure, when the circuit area CA and the light emitting area EA overlap each other, when the light emitted from the light emitting area EA moves downward, the circuit area CA ), the light emission is interrupted and the transmittance is reduced. On the other hand, in the case of the upper light-emitting structure, even if the circuit area (CA) and the light-emitting area (EA) overlap each other, in the light-emitting area (EA) This is because the light emission is not interrupted by the circuit area CA when the emitted light moves upward.

FIGS. 3A to 3C are schematic plan views of one pixel constituting an electroluminescent display device according to an embodiment of the present invention, which illustrates the leftmost pixel of FIG. 2 . FIGS. 3A and 3B show the bank layer BL being patterned without alignment error, and FIG. 3B shows only the bank layer BL and the pixel electrode PE in FIG. 3A. FIG. 3C shows an alignment error occurring in the bank layer BL, and like FIG. 3B, it shows only the bank layer BL and the pixel electrode PE.

As can be seen in FIG. 3A, the electroluminescent display device according to an embodiment of the present invention includes a gate line (GL), a reference line (Ref1), a data line (DL1), a pixel electrode (PE), a thin film transistor (TFT), and a bank layer (BL).

The gate line GL is arranged horizontally, and the reference line Ref1 and the data line DL1 are arranged vertically.

The pixel electrode PE extends from the light emitting area EA to the circuit area CA and may be electrically connected to the thin film transistor TFT, particularly the driving thin film transistor.

The thin film transistor (TFT) is formed in the circuit area (CA). As described above, a plurality of thin film transistors performing various functions may be formed in the circuit area CA. For convenience, the drawing schematically shows only the driving thin film transistor that can be electrically connected to the pixel electrode PE. , this also applies to the following embodiments.

The bank layer BL is patterned to define the light emitting area EA. Specifically, the bank layer BL is patterned to overlap the gate line GL, the reference line Ref1, and the data line DL1 as well as the circuit area CA. Additionally, the bank layer BL is patterned to overlap the edge of the pixel electrode PE. For reference, in the drawing, the bank layer BL is indicated by hatching.

Referring to FIG. 3B, the pixel electrode (PE) and the bank layer (BL) will be described in more detail as follows.

As can be seen in FIG. 3B, the pixel electrode PE includes an electrode portion 110, a connection portion 120, and a contact portion 130.

The electrode unit 110 is provided in the light emitting area EA and emits light from the electrode unit 110 area. The contact portion 130 is provided in the circuit area CA and is electrically connected to the thin film transistor (TFT). The connection part 120 connects the electrode part 110 and the contact part 130. The electrode portion 110, the connecting portion 120, and the contact portion 130 are patterned simultaneously with the same material, and therefore, the electrode portion 110, the connecting portion 120, and the contact portion ( 130) is formed as a whole as one body.

The connection portion 120 extends from the light emitting area EA to the circuit area CA, and thus, for example, extends in the vertical direction. The width W2 of the connection portion 120 in a direction perpendicular to the direction in which the connection portion 120 extends, for example, the horizontal direction, is formed to be smaller than the width W1 of the electrode portion 110 in the horizontal direction. . Additionally, the horizontal width W2 of the connection portion 120 is formed to be smaller than the horizontal width W3 of the contact portion 130.

The reason why the horizontal width W2 of the connection portion 120 is formed to be relatively small is to facilitate the process of repairing the defective pixel when a specific pixel is determined to be defective in the pixel inspection process. am. Specifically, when a defective pixel occurs, the defective pixel can be repaired by blocking the electrical connection between the pixel electrode (PE) of the defective pixel and the thin film transistor (TFT). Accordingly, by forming the width W2 of the connection portion 120 of the pixel electrode PE to be small, the connection portion 120 can be more easily broken using a laser or the like. In order to facilitate the repair process of defective pixels, the width W2 of the connecting portion 120 is made small, and as a result, the problem of cracks occurring in the connecting portion 120 during the manufacturing process may occur as in the past. there is. In other words, if the width W2 of the connection part 120 is made large, the problem of cracks occurring in the connection part 120 during the manufacturing process can be reduced as in the past, but in this case, the repair process for defective pixels becomes difficult. There is a problem. Therefore, the present invention provides a method to facilitate the repair process of defective pixels by forming the width W2 of the connecting portion 120 to be small and to prevent the problem of cracks occurring in the connecting portion 120 during the manufacturing process. It is done.

To this end, according to an embodiment of the present invention, the bank layer BL is provided with a crack prevention portion 250. The crack prevention portion 250 of the bank layer BL is formed at a position facing the connection portion 120 of the pixel electrode PE, so that even if an alignment process error of the bank layer BL occurs, the pixel It serves to prevent cracks from occurring in the connection portion 120 of the electrode (PE). The crack prevention portion 250 is patterned using the same material as the bank layer BL through the same process.

If an alignment process error does not occur, the bank layer BL overlaps the entire connection portion 120 and the contact portion 130 of the pixel electrode PE and is connected to the electrode portion 110 of the pixel electrode PE. The pattern is formed to overlap the edge. Therefore, when an alignment process error does not occur, the bank layer BL has an open area OA to expose a portion of the pixel electrode PE, specifically the central portion of the electrode portion 110, and exposes the pixel electrode PE. A pattern is formed to cover the electrode (PE). The open area (OA) of the bank layer (BL) defines the area where light is emitted from the light emitting area (EA).

The portion where the bank layer BL overlaps the edge of the electrode portion 110 of the pixel electrode PE will be described in more detail as follows.

The electrode portion 110 has a first side 111, a second side 112, and a third side 113. For example, when the electrode portion 110 is formed in a square shape, the first side 111 constitutes the upper side, the second side 112 constitutes the left and right sides, and the third side 113 constitutes the riverside. The third side 113 of the electrode portion 110 is the side in contact with the connection portion 120.

As an internal side in contact with the open area OA, the bank layer BL has a first side 211, a second side 212, and a third side 213. The first side 211 of the bank layer BL faces the first side 111 of the electrode unit 110, and the second side 212 of the bank layer BL faces the electrode unit ( 110), and the third side 213 of the bank layer BL faces the third side 113 of the electrode portion 110. When an alignment process error does not occur in the bank layer BL, the first side 211 of the bank layer BL is parallel to the first side 111 of the electrode portion 110, and the bank The second side 212 of the layer BL is parallel to the second side 112 of the electrode portion 110, and the third side 213 of the bank layer BL is parallel to the second side 112 of the electrode portion 110. It is parallel to the third side (113). In addition, the distance between the first side 211 of the bank layer BL and the first side 111 of the electrode portion 110 is maintained constant, and the second side 212 of the bank layer BL ) and the second side 112 of the electrode portion 110 is also maintained constant, and the third side 213 of the bank layer BL and the third side 113 of the electrode portion 110 ) can also be kept constant.

At this time, the crack prevention portion 250 of the bank layer BL protrudes from the third side 213 of the bank layer BL toward the open area OA. In other words, the crack prevention portion 250 of the bank layer BL protrudes from the third side 213 of the bank layer BL toward the inside of the electrode portion 110 of the pixel electrode PE. . The third side 213 of the bank layer BL should be understood as excluding the side constituting the crack prevention portion 250.

When an alignment process error of the bank layer (BL) does not occur, the crack prevention unit 250 does not overlap the connection part 110 of the pixel electrode (PE), but other than the crack prevention unit 250 Since the bank layer BL area overlaps the connection portion 110 of the pixel electrode PE, cracks can be prevented from occurring in the connection portion 120 of the pixel electrode PE.

In addition, even if an alignment process error of the bank layer BL occurs and the bank layer BL is formed to be pushed downward as a whole, the crack prevention portion 250 is connected to the connection portion 120 of the pixel electrode PE. ) and covers the connection portion 120 of the pixel electrode (PE), thereby preventing cracks from occurring in the connection portion 120 of the pixel electrode (PE).

If the crack prevention portion 250 is formed to be large, it is possible to more effectively prevent cracks in the connection portion 120 of the pixel electrode (PE) when an error in the alignment process occurs. However, in this case, the transmittance in the light emitting area (EA) is reduced. There is a downside. Therefore, it is desirable to form the crack prevention portion 250 to an appropriate size to minimize a decrease in transmittance at a position facing the connection portion 120 of the pixel electrode PE.

Hereinafter, with reference to FIG. 3C, what happens when an alignment process error of the bank layer BL occurs will be described.

FIG. 3C shows a pattern formed in the structure of FIG. 3B such that an alignment process error of the bank layer BL occurs and the bank layer BL is pushed downward as a whole.

In the case of FIG. 3B described above, the bank layer BL is formed to overlap the entire edge of the electrode portion 110 of the pixel electrode PE and at the same time overlaps the entire connection portion 120 of the pixel electrode PE. In this case, the third side 213 of the bank layer BL is formed above the third side 113 of the electrode portion 110. Accordingly, the entire open area OA of the bank layer BL is formed in the inner area of the electrode unit 110.

On the other hand, in the case of FIG. 3C, the bank layer BL is formed so as not to overlap a portion of the edge of the electrode portion 110 of the pixel electrode PE, particularly at least a portion of the third side 113. In this case, The third side 213 of the bank layer BL is formed below the third side 113 of the electrode portion 110. In particular, the third side 113 of the electrode portion 110 is between the third side 213 of the bank layer BL and the upper side of the crack prevention portion 250 (see reference numeral 251 in FIG. 4A). Located. Accordingly, part of the open area OA of the bank layer BL is formed in the outer area of the electrode unit 110.

However, even in the case of FIG. 3C, the bank layer BL is formed to overlap the entire connection portion 120 of the pixel electrode PE to cover the entire connection portion 120 of the pixel electrode PE. That is, at least a portion of the crack prevention portion 250 of the bank layer BL is formed above the third side 113 of the electrode portion 110, and thus the connection portion 120 of the pixel electrode PE ) is prevented from being exposed without being covered by the bank layer BL by the crack prevention portion 250 of the bank layer BL. That is, the connection portion 120 of the pixel electrode PE is formed by a combination of the crack prevention portion 250 of the bank layer BL and other parts of the bank layer BL excluding the crack prevention portion 250. By being obscured, cracks can be prevented from occurring in the connection portion 120 of the pixel electrode PE.

Hereinafter, the crack prevention portion 250 of the bank layer BL according to various embodiments of the present invention will be described. In the following embodiments, the same reference numerals are assigned to the same components as the embodiments shown in FIGS. 3A to 3C, and detailed descriptions of the same components will be omitted.

FIG. 4A is a schematic plan view showing a crack prevention portion of a bank layer according to an embodiment of the present invention, and FIG. 4B is a cross section of lines A-B and C-D of FIG. 4A, showing an electroluminescent display device according to an embodiment of the present invention. This is a cross-sectional view of .

As can be seen in FIG. 4A, the pixel electrode PE includes an electrode portion 110, a connection portion 120, and a contact portion 130, and the electrode portion 110 includes the second side 112 and It is provided with a third side (113).

The bank layer BL has an open area OA exposing the central portion of the electrode portion 110 and overlaps the edge of the electrode portion 110 and the entirety of the connection portion 120 and the contact portion 130. It is formed as much as possible. The bank layer BL is a side in contact with the open area OA, a second side 212 facing the second side 112 of the electrode portion 110, and a second side 212 facing the second side 112 of the electrode portion 110. It is provided with a third side (213) facing the third side (113). Additionally, the bank layer BL has a crack prevention portion 250 protruding from the third side 213 toward the open area OA.

The crack prevention portion 250 has an upper side 251 and a side side 252. At least a portion of the upper side 251 of the crack prevention portion 250 constitutes the upper end of the crack prevention portion 250.

The upper side 251 of the crack prevention portion 250 may be formed in a straight structure parallel to the third side 213 of the bank layer BL or the third side 113 of the electrode portion 110. However, it is not necessarily limited to that. For example, the upper side 251 of the crack prevention portion 250 may be formed in an inclined straight structure or may be formed in a curved structure.

When the upper side 251 of the crack prevention portion 250 has a parallel straight structure, the top of the crack prevention portion 250 may be the entire upper side 251, and the crack prevention portion 250 If the upper side 251 of is formed in an inclined straight line or curved structure, the top of the crack prevention portion 250 may be any one point of the upper side 251.

The upper side 251 or top of the crack prevention portion 250 is located farther from the third side 113 of the electrode portion 110 than the third side 213 of the bank layer BL. That is, the distance D1 from the third side 113 of the electrode portion 110 to the upper side 251 or the top of the crack prevention portion 250 is the third side 113 of the electrode portion 110. is farther than the distance D2 of the third side 213 of the bank layer BL. In this specification, the distance between two components should be interpreted as the shortest distance between the two components.

The side side 252 of the crack prevention portion 250 connects the upper side 251 of the crack prevention portion 250 and the third side 213 of the bank layer BL. The side sides 252 are formed on the left and right sides of the upper side 251, respectively. The side sides 252 are formed in an inclined straight structure, and accordingly, the crack prevention portion 250 is formed in a square shape. In particular, the side side 252 provided on the left side of the upper side 251 and the side side 252 provided on the right side of the upper side 251 may be formed in a symmetrical structure, and in this case, the crack prevention portion 250 is formed in a trapezoidal shape.

The width W4 of the crack prevention portion 250 may be formed to be larger than the width W2 of the connection portion 120 of the pixel electrode PE. However, it is not necessarily limited thereto, and the width W4 of the crack prevention portion 250 may be formed to be the same as the width W2 of the connection portion 120 of the pixel electrode PE. The width W4 of the crack prevention portion 250 may be formed to be smaller than the width W2 of the connection portion 120 of the pixel electrode PE. However, if the width W4 of the crack prevention portion 250 is formed larger than the width W2 of the connection portion 120 of the pixel electrode PE, an error in the alignment process of the bank layer BL occurs. It is more effective in preventing cracks in the connection portion 120 of the pixel electrode (PE).

Additionally, the width W5 of the upper side 251 of the crack prevention portion 250 may be formed to be the same length as the width W2 of the connection portion 120 of the pixel electrode PE. In this case, the left and right ends of the upper side 251 of the crack prevention portion 250 are formed at positions corresponding to the left and right ends of the connection portion 120 of the pixel electrode PE. However, it is not necessarily limited thereto, and the width W5 of the upper side 251 of the crack prevention portion 250 may be formed to be larger than the width W2 of the connection portion 120 of the pixel electrode PE. In some cases, the width W5 of the upper side 251 of the crack prevention portion 250 may be formed to be smaller than the width W2 of the connection portion 120 of the pixel electrode PE. However, the bank layer BL is such that the width W5 of the upper side 251 of the crack prevention portion 250 is equal to or larger than the width W2 of the connection portion 120 of the pixel electrode PE. It may be more effective in preventing cracks in the connection portion 120 of the pixel electrode (PE) when an error in the alignment process occurs.

Hereinafter, the cross-sectional structure of the electroluminescence display device according to an embodiment of the present invention will be described with reference to FIG. 4B.

As can be seen in FIG. 4B, an active layer 20, a gate insulating film 25, a gate electrode 30, an interlayer insulating film 35, a source electrode 40a, and a drain electrode 40b are formed on the substrate 10. A thin film transistor (TFT) is formed.

The active layer 20 functions as an electron movement channel and is formed on the substrate 10. The gate insulating film 25 functions to insulate the active layer 20 and the gate electrode 30, and is formed on the active layer 20. The gate insulating layer 25 may be formed in the same pattern as the gate electrode 30. The gate electrode 30 is formed on the gate insulating film 25. The interlayer insulating film 35 is formed on the gate electrode 30. The interlayer insulating film 35 has a first contact hole (C1) exposing one end of the active layer 20 and a second contact hole (C2) exposing the other end of the active layer 20, and the substrate ( It is formed on the entire surface of 10). The source electrode 40a and the drain electrode 40b are formed on the interlayer insulating film 35. The source electrode 40a is connected to one end of the active layer 20 through the first contact hole C1, and the drain electrode 40b is connected to the active layer through the second contact hole C2. It is connected to the other end of (20).

The above thin film transistor (TFT) relates to a top gate structure in which the gate electrode 30 is formed on the active layer 20, and the present invention is not necessarily limited thereto, but the gate electrode ( 30) may be changed into various forms known in the art, including a bottom gate structure formed below the active layer 20.

A protective film 45 and a planarization film 50 are sequentially formed on the source electrode 40a and the drain electrode 40b of the thin film transistor (TFT).

The protective film 45 is formed on the source electrode 40a and the drain electrode 40b, and functions to protect the thin film transistor underneath. The planarization film 50 is formed on the protective film 45 and functions to planarize the surface of the substrate 10.

A pixel electrode (PE) is formed on the planarization film 50. The pixel electrode PE is connected to the source electrode 40a through a third contact hole C3 provided in the protective film 45 and the planarization film 50. In some cases, the third contact hole C3 may be provided in the protective film 45 and the planarization film 50 to expose the drain electrode 40b, and in this case, the pixel electrode PE is It can be connected to the drain electrode 40b through the third contact hole C3.

A bank layer (BL) is formed on the pixel electrode (PE). The bank layer BL extends from the planarization film 50 over the pixel electrode PE. In particular, since the bank layer BL in the area corresponding to lines A-B in FIG. 4A is provided with the crack prevention portion 250, the pixel electrode PE is stronger than the bank layer BL in the area corresponding to lines C-D in FIG. 4A. ) extends further upward.

A light-emitting layer 300 is formed on the pixel electrode PE, and a counter electrode 350 is formed on the light-emitting layer 300.

The light emitting layer 300 may be made of various materials known in the art that emit light. For example, the light-emitting layer 300 may be composed of a stacked structure of a hole injection layer, a hole transport layer, an organic light-emitting layer, an electron transport layer, and an electron injection layer. Although the drawing shows the light emitting layer 300 formed only on the pixel electrode PE, in some cases, the light emitting layer 300 may also be formed on the bank layer BL.

The counter electrode 350 is formed on the light emitting layer 300. The counter electrode 350 may also be formed on the bank layer BL. The pixel electrode (PE) functions as an anode (Anode) and the counter electrode 350 functions as a cathode (Cathode), so that an electric field is generated between the pixel electrode (PE) and the counter electrode (Anode), and the generated electric field The light emitting layer 300 can emit light.

Figures 5 to 8 are schematic plan views showing crack prevention parts of the bank layer according to various embodiments of the present invention, and hereinafter, only the configuration different from the above-described Figure 4a will be described.

In the case of FIG. 4A described above, the side side 252 of the crack prevention portion 250 has an inclined straight structure.

In contrast, in the case of FIG. 5, the side side 252 of the crack prevention portion 250 has a curved structure. In particular, the side side 252 of the curved structure is formed in a convex structure toward the open area OA, and accordingly, the area of the crack prevention portion 250 according to FIG. 5 is smaller than that of the crack prevention portion 250 according to FIG. 4A. It can be formed larger than the area. However, it is not necessarily limited thereto, and the curved side side 252 is formed in a concave structure toward the open area OA, so that the area of the crack prevention portion 250 is smaller than the area of the crack prevention portion 250 according to FIG. 4A. It is also possible to form

In addition, in the case of FIG. 6, the side 252 of the crack prevention portion 250 has a straight structure that is not inclined. That is, the side side 252 of the crack prevention portion 250 may be formed to be perpendicular to the upper side 251 of the crack prevention portion 250.

In the case of FIG. 4a described above, the side sides 252 of the crack prevention portion 250 are formed on both left and right sides centered on the upper side 251 of the crack prevention portion 250, and accordingly, the crack prevention portion 250 is formed on the bank layer BL. ) is formed so as not to contact the second side 212 of ).

In contrast, in the case of FIGS. 7 and 8, the side side 252 of the crack prevention portion 250 is formed only on one side, for example, the right side, of the upper side 251 of the crack prevention portion 250, and accordingly, the crack prevention portion 250 comes into contact with the second left side 212 of the bank layer BL. That is, in the case of FIGS. 7 and 8, the upper side 251 of the crack prevention portion 250 is in contact with the second side 212 of the bank layer BL. Although not shown, the side side 252 of the crack prevention portion 250 is formed only on the left side of the upper side 251 of the crack prevention portion 250, and accordingly, the crack prevention portion 250 is formed on the right side of the bank layer BL. It may be formed to contact the second side (212).

In the case of FIG. 7 , the upper side 251 of the crack prevention portion 251 is formed to face the entire width W2 direction area of the connection portion 120 of the pixel electrode PE. That is, the upper side 251 of the crack prevention portion 251 is formed to face both the left and right ends of the connection portion 120 of the pixel electrode PE. Accordingly, the right end of the upper side 251 of the crack prevention portion 251 in contact with the side side 252 is formed so that it matches the right end of the connection portion 120 of the pixel electrode PE or is located further to the right. It can be.

In the case of FIG. 8, the upper side 251 of the crack prevention portion 251 is formed to face a portion of the area in the width W2 direction of the connection portion 120 of the pixel electrode PE but not the remaining portion. . That is, the upper side 251 of the crack prevention portion 251 faces the left end of the connection portion 120 of the pixel electrode PE, but is formed so as not to face the right end of the connection portion 120. . Accordingly, the right end of the upper side 251 of the crack prevention portion 251, which is in contact with the side side 252, is formed to be located between the left and right ends of the connection portion 120 of the pixel electrode PE.

In the case of FIG. 8, when an alignment process error of the bank layer BL occurs and the bank layer BL is formed to be pushed downward as a whole, the crack prevention portion 250 is connected to the connection portion of the pixel electrode PE. It may overlap with one side (for example, the left side) of the pixel electrode (PE), but may not overlap with the other side (for example, the right side) of the connection part 120 of the pixel electrode (PE). However, even in the case of FIG. 8, at least one side of the connection portion 120 of the pixel electrode PE in the width W2 direction is covered by the crack prevention portion 250, so that the entire connection portion 120 Cracks can be prevented, and there are no problems with signal transmission.

Meanwhile, although not shown, in the case of FIGS. 7 and 8, the side side 252 of the crack prevention portion 251 is not formed as an inclined straight structure, but may be formed as a curved structure as shown in FIG. 5 described above. As shown in FIG. 6 described above, it may be formed in a non-slanted straight structure, that is, perpendicular to the upper side 251 of the crack prevention portion 250.

9 to 11 are schematic plan views showing pixel electrodes and bank layers according to various embodiments of the present invention, and hereinafter, only configurations different from the above-described embodiments will be described.

In the above-described embodiments, the electrode portion 110 of the pixel electrode PE is formed in a shape similar to a rectangle, and accordingly, the open area OA of the bank layer BL is also formed except for the crack prevention portion 250 area. The overall shape is similar to a rectangle.

On the other hand, in the embodiments shown in FIGS. 9 to 11, the electrode portion 100 of the pixel electrode PE has a structure of various shapes, for example, various polygonal shapes.

Since thin film transistors and capacitors of various structures, and wiring for electrical connection between them, are formed in the above-mentioned circuit area (CA), the circuit area (CA) can be changed in various ways to place complex circuits in optimal positions. The shape of the electrode portion 110 of the pixel electrode PE may also change in various ways according to changes in the circuit area CA. The embodiments according to FIGS. 9 to 11 show the shape of the electrode portion 110 of the pixel electrode PE being changed in various ways according to the change of the circuit area CA. The present invention does not necessarily apply to FIGS. It is not limited thereto, and may be changed in various ways other than the structure shown in FIGS. 9 to 11.

In the case of the embodiment according to FIG. 9, the length of the lower side of the electrode portion 110 is shorter than the upper side of the electrode portion 110, and the lower side of the electrode portion 110 and the side side of the electrode portion 110 ( For example, there is a slope between the left sides. The lower side of the electrode portion 110 is the side in contact with the connection portion 120. In the case of FIG. 9, additional space in the circuit area CA can be secured below the inclined surface compared to the above-described embodiments.

In the case of the embodiment according to FIG. 9, the bank layer BL overlaps the edge of the electrode portion 110 and has an open area OA. The open area (OA) of the bank layer (BL) is formed in a similar shape to the electrode unit 110 except for the crack prevention unit 250 area, and the electrode unit 110 is formed through the open area OA. The central part may be exposed. As in the above-described embodiments, the crack prevention portion 250 extends from the lower side of the bank layer BL facing the lower side of the electrode portion 110 toward the open area OA or inside the electrode portion 110. It protrudes in the direction of the area.

In the embodiment according to FIG. 10, the inclined surface between the lower side of the electrode portion 110 and the side side (for example, the left side) of the electrode portion 110 is formed in a stepped structure rather than a straight structure, and accordingly, the bank layer (BL) ) is also the same as the embodiment according to FIG. 9 except that the open area OA is formed in a similar shape to the electrode portion 110.

In the case of the embodiment according to FIG. 11, the connection part 120 is connected to the lower left side of the electrode part 110, and at this time, the lower left side of the electrode part 110 in contact with the connection part 120 is formed at a relatively high position. The lower right side of the electrode portion 110, which is not in contact with the connection portion 120, is formed at a relatively low position.

In the case of the embodiment according to FIG. 11, the bank layer BL overlaps the edge of the electrode portion 110 and has an open area OA. Accordingly, the bank layer BL has a lower left side facing the lower left side of the electrode portion 110 and a lower right side facing the lower right side of the electrode portion 110. At this time, the crack prevention portion 250 of the bank layer BL protrudes from the lower left side of the bank layer BL toward the open area OA or toward the inner region of the electrode portion 110.

Although embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications may be made without departing from the technical spirit of the present invention. . Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. The scope of protection of the present invention should be interpreted in accordance with the claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of rights of the present invention.

GL: Gate line DL1 DL2, DL3, DL4: Data line
Ref1, Ref2: Reference line TFT: Thin film transistor
PE: pixel electrode BL: bank layer
110: electrode part 120: connection part
130: contact part 250: crack prevention part

Claims (18)

Pixel electrodes provided for each pixel;
a thin film transistor electrically connected to the pixel electrode; and
It includes a bank layer having an open area to expose a portion of the pixel electrode to define a light emitting area,
The pixel electrode includes an electrode portion provided in the light emitting area, a contact portion electrically connected to the thin film transistor, and a connection portion connecting the electrode portion and the contact portion,
In order to prevent cracks from occurring in the connection portion of the pixel electrode, the bank layer is provided with a local crack prevention portion at a position facing the connection portion,
In a second direction perpendicular to the first direction in which the connection part extends, the width of the crack prevention part is provided to be greater than the width of the connection part,
The electrode portion includes one side in contact with the connection portion,
The bank layer is in contact with the open area and includes one side facing one side of the electrode portion,
The crack prevention portion is an electroluminescent display device in which the crack prevention portion protrudes from one side of the bank layer toward the inside of the electrode portion. delete delete delete Pixel electrodes provided for each pixel;
a thin film transistor electrically connected to the pixel electrode; and
It includes a bank layer having an open area to expose a portion of the pixel electrode to define a light emitting area,
The pixel electrode includes an electrode portion provided in the light emitting area, a contact portion electrically connected to the thin film transistor, and a connection portion connecting the electrode portion and the contact portion,
In order to prevent cracks from occurring in the connection portion of the pixel electrode, the bank layer is provided with a crack prevention portion at a position facing the connection portion,
The electrode portion includes one side in contact with the connection portion,
The bank layer is in contact with the open area and includes one side facing one side of the electrode portion,
The crack prevention portion protrudes from one side of the bank layer toward the inside of the electrode portion,
The crack prevention portion has an upper side and a side side connecting the upper side and one side of the bank layer,
The electroluminescent display is provided such that the left end of the upper side of the crack prevention part coincides with the left end of the connection part or is located to the left of it, or the right end of the upper side of the crack prevention part coincides with the right end of the connection part or is located to the right of it. Device. Pixel electrodes provided for each pixel;
a thin film transistor electrically connected to the pixel electrode; and
It includes a bank layer having an open area to expose a portion of the pixel electrode to define a light emitting area,
The pixel electrode includes an electrode portion provided in the light emitting area, a contact portion electrically connected to the thin film transistor, and a connection portion connecting the electrode portion and the contact portion,
In order to prevent cracks from occurring in the connection portion of the pixel electrode, the bank layer is provided with a crack prevention portion at a position facing the connection portion,
The electrode portion includes one side in contact with the connection portion,
The bank layer is in contact with the open area and includes one side facing one side of the electrode portion,
The crack prevention portion protrudes from one side of the bank layer toward the inside of the electrode portion,
The crack prevention portion has an upper side and a side side connecting the upper side and one side of the bank layer,
An electroluminescent display device wherein one end of the upper side of the crack prevention portion is positioned between the left end and the right end of the connection portion. Pixel electrodes provided for each pixel;
a thin film transistor electrically connected to the pixel electrode; and
It includes a bank layer having an open area to expose a portion of the pixel electrode to define a light emitting area,
The pixel electrode includes an electrode portion provided in the light emitting area, a contact portion electrically connected to the thin film transistor, and a connection portion connecting the electrode portion and the contact portion,
In order to prevent cracks from occurring in the connection portion of the pixel electrode, the bank layer is provided with a crack prevention portion at a position facing the connection portion,
The electrode portion includes one side in contact with the connection portion,
The bank layer is in contact with the open area and includes one side facing one side of the electrode portion,
The crack prevention portion protrudes from one side of the bank layer toward the inside of the electrode portion,
The electrode portion includes a second side connected to one side of the electrode portion, and the bank layer includes a second side facing the other side of the electrode portion,
An electroluminescent display device wherein the crack prevention portion is provided so as not to contact the other side of the bank layer. According to paragraph 1,
The electrode portion includes a second side connected to one side of the electrode portion, and the bank layer includes a second side facing the other side of the electrode portion,
An electroluminescent display device wherein the crack prevention portion is provided to contact the other side of the bank layer. According to paragraph 1,
An electroluminescent display device wherein the distance from one side of the electrode portion to the top of the crack prevention portion is greater than the distance from one side of the electrode portion to one side of the bank layer. According to clause 9,
The electroluminescent display device wherein the bank layer overlaps the connection portion and the crack prevention portion does not overlap the connection portion. According to paragraph 1,
An electroluminescent display device wherein one side of the electrode portion is located between an upper end of the crack prevention portion and one side of the bank layer. According to clause 11,
The crack prevention portion is provided to overlap the connection portion. a pixel electrode including an electrode portion provided in a light emitting area, a contact portion electrically connected to a thin film transistor, and a connection portion connecting the electrode portion and the contact portion; and
It includes a bank layer provided to overlap the edges of the electrode portion and having an open area for exposing the central portion of the electrode portion,
In order to prevent cracks from occurring in the connection portion of the pixel electrode, the bank layer is provided with a local crack prevention portion at a position facing the connection portion,
In a second direction perpendicular to the first direction in which the connection part extends, the width of the crack prevention part is provided to be greater than the width of the connection part,
The electrode portion includes one side in contact with the connection portion,
The bank layer is in contact with the open area and includes one side facing one side of the electrode portion,
The crack prevention portion is an electroluminescent display device in which the crack prevention portion protrudes from one side of the bank layer toward the center of the electrode portion. delete According to clause 13,
The electroluminescent display device wherein the bank layer overlaps the connection portion and the crack prevention portion does not overlap the connection portion. a pixel electrode including an electrode portion provided in a light emitting area, a contact portion electrically connected to a thin film transistor, and a connection portion connecting the electrode portion and the contact portion; and
It includes a bank layer provided to overlap at least a portion of an edge of the electrode portion,
In order to prevent cracks from occurring in the connection portion of the pixel electrode, the bank layer is provided with a crack prevention portion that locally protrudes into the inner region of the electrode portion at a position facing the connection portion, and at least a portion of the crack prevention portion is It is provided to overlap the connection part,
The electroluminescent display device wherein the width of the crack prevention portion is greater than the width of the connection portion in a second direction perpendicular to the first direction in which the connection portion extends. delete According to clause 16,
The electroluminescent display device is provided so that the connection portion is covered by a combination of the crack prevention portion and other portions of the bank layer excluding the crack prevention portion.

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