KR102593488B1 - Flexible electroluminescent display device - Google Patents

Abstract

A flexible electroluminescent display device according to an embodiment of the present specification includes a shield layer on a flexible substrate, a buffer layer on the shield layer, a thin film transistor on the buffer layer, and an electroluminescent element on the thin film transistor, and the shield layer The thin film transistor has an overlapping area, and the thin film transistor and the shield layer are connected in the overlapping area, thereby improving the process.

Description

Flexible electroluminescent display device and manufacturing method thereof {FLEXIBLE ELECTROLUMINESCENT DISPLAY DEVICE}

This specification relates to a flexible electroluminescent display device and a manufacturing method thereof, and more specifically, to a flexible electroluminescent display device and a manufacturing method thereof that can improve the process of the flexible electroluminescent display device.

As we enter the information age, the field of display devices that visually display electrical information signals is developing rapidly, and research is continuing to develop performance such as thinner, lighter, and lower power consumption for various display devices.

Representative display devices include Liquid Crystal Display device (LCD), Field Emission Display device (FED), Electro-Wetting Display device (EWD), and Organic Light Emitting Display device (Organic Light Emission Display). Light Emitting Display Device (OLED), etc.

Electroluminescent displays, including organic light emitting displays, are self-luminous displays, and unlike liquid crystal displays, they do not require a separate light source and can be manufactured in a lightweight and thin form. In addition, electroluminescent display devices are not only advantageous in terms of power consumption due to low voltage operation, but also have excellent color reproduction, response speed, viewing angle, and contrast ratio (CR), and are expected to be utilized in various fields.

In an electroluminescent display device, an emissive layer (EML) made of organic material is placed between two electrodes, an anode and a cathode. When holes from the anode are injected into the light-emitting layer and electrons from the cathode are injected into the light-emitting layer, the injected electrons and holes recombine with each other to form excitons in the light-emitting layer and emit light.

Additionally, the light-emitting layer contains a host material and a dopant material, and interaction between the two materials occurs. The host generates excitons from electrons and holes and transfers energy to the dopant. The dopant is a dye-like organic substance added in small amounts and serves to receive energy from the host and convert it into light.

An electroluminescent display device containing a light-emitting layer made of organic materials encapsulates the electroluminescent display device with glass, metal, or film to prevent moisture or oxygen from entering the electroluminescent display device from the outside. It blocks inflow to prevent oxidation of the light-emitting layer and electrode, and protects it from external mechanical or physical shock.

As display devices become smaller, efforts are being made to reduce the bezel area, which is the outer portion of the active area (A/A), in order to increase the size of the effective display screen in the same area of the display device.

Since wiring and driving circuits for driving the screen are generally placed in the bezel area, which is the non-active area (N/A), there was a limit to reducing the bezel area.

In the recently developed flexible electroluminescent display device that can maintain display performance even when bent by applying a flexible substrate made of a soft material such as plastic, the bezel area is secured while securing area for wiring and driving circuits. To reduce the size, the non-display area of the flexible substrate can be bent.

However, the flexible substrate included in the electroluminescent display device may deteriorate the performance of the thin film transistor disposed on the top due to charged charges generated on the substrate when the electroluminescent display device is operated for a long period of time.

Thin film transistors included in flexible electroluminescent displays contain multiple contact holes and require multiple steps, making production difficult.

Accordingly, the inventor of the present specification recognized the above-mentioned problem and invented a flexible electroluminescent display device including a thin film transistor with a new structure.

In addition, the inventor of the present specification recognized that as the resolution of electroluminescent display devices gradually increases, there is a shortage of space for wiring, and developed an electroluminescent display device with a new structure that allows wiring to be arranged more freely within a limited space. invented.

The problem to be solved according to the embodiments of the present specification is to provide an electroluminescent display device that can reduce the influence of the thin film transistor on the semiconductor layer by forming a shield layer.

The problem according to the embodiments of the present specification is to provide a method of manufacturing an electroluminescent display device in which the process of connecting the shield layer and the electrode can be simplified.

The tasks of this specification are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

A flexible electroluminescent display device according to an embodiment of the present specification includes a shield layer on a flexible substrate, a buffer layer on the shield layer, a thin film transistor on the buffer layer, and an electroluminescent element on the thin film transistor, and the shield layer The thin film transistor has an overlapping area, and the thin film transistor and the shield layer are connected in the overlapping area.

A flexible electroluminescent display device according to an embodiment of the present specification includes forming a shield layer on a flexible substrate, forming a buffer layer on the shield layer, and forming a semiconductor layer, a gate electrode, a source electrode, and a drain electrode on the buffer layer. The manufacturing process includes forming a thin film transistor, forming an electroluminescent element on the thin film transistor, and the shield layer and the thin film transistor have an overlapping area, and connecting the thin film transistor and the shield layer in the overlapping area. .

The electroluminescent display device according to an embodiment of the present specification has the effect of improving the performance of the thin film transistor by forming a shield layer to reduce the influence of charges on the flexible substrate on the semiconductor layer of the thin film transistor.

The electroluminescent display device according to an embodiment of the present specification has the effect of forming a contact hole connecting the shield layer and the electrode without an additional process.

The electroluminescent display device according to an embodiment of the present specification has the effect of allowing wiring used in the flexible electroluminescent display device to be more freely arranged within a limited space.

The effects according to the embodiments of the present specification are not limited to the contents exemplified above, and further various effects are included in the present specification.

Since the contents of the specification described in the problem to be solved, the means to solve the problem, and the effect described above do not specify the essential features of the claim, the scope of the claim is not limited by the matters described in the content of the specification.

1 is a block diagram of an electroluminescence display device according to an embodiment of the present specification.
Figure 2 is a circuit diagram of a pixel included in an electroluminescence display device according to an embodiment of the present specification.
Figure 3 is a plan view of an electroluminescent display device according to an embodiment of the present specification.
4A and 4B are cross-sectional views of detailed structures of a display area and a bending area of an electroluminescence display device according to an embodiment of the present specification.
5A and 5B are cross-sectional views of the shield layer connection structure included in the electroluminescence display device according to the first and second embodiments of the present specification.
6A to 6D illustrate the manufacturing process of the shield layer connection structure included in the electroluminescence display device according to the second embodiment of the present specification.
Figure 7 is a cross-sectional view of a bending area of a flexible electroluminescent display device according to an embodiment of the present specification.

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. The present 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.

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 technological 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.

Figure 1 is a block diagram of an electroluminescent display device 100 according to an embodiment of the present specification.

Referring to FIG. 1 , the electroluminescent display device 100 includes an image processing unit 110, a timing controller 120, a data driver 130, a gate driver 140, and a display panel 150.

The image processing unit 110 outputs a data enable signal (DE) in addition to a data signal (DATA) supplied from the outside. In addition to the data enable signal (DE), the image processing unit 110 may output one or more of a vertical synchronization signal, a horizontal synchronization signal, and a clock signal.

The timing controller 120 receives a data enable signal (DE) or a driving signal including a vertical synchronization signal, a horizontal synchronization signal, and a clock signal, as well as a data signal (DATA) from the image processing unit 110. The timing controller 120 includes a gate timing control signal (GDC) for controlling the operation timing of the gate driver 140 and a data timing control signal (DDC) for controlling the operation timing of the data driver 130 based on the driving signal. outputs.

The data driver 130 samples and latches the data signal (DATA) supplied from the timing controller 120 in response to the data timing control signal (DDC) supplied from the timing controller 120, converts it to a gamma reference voltage, and outputs it. . The data driver 130 outputs a data signal (DATA) through the data lines (DL1 to DLn).

The gate driver 140 outputs a gate signal while shifting the level of the gate voltage in response to the gate timing control signal (GDC) supplied from the timing controller 120. The gate driver 140 outputs a gate signal through the gate lines GL1 to GLm.

The display panel 150 displays an image as the pixel 160 emits light in response to the data signal (DATA) and gate signal supplied from the data driver 130 and the gate driver 140. The structure of the pixel 160 is explained in FIGS. 2 and 3.

Figure 2 is a circuit diagram of a pixel included in an electroluminescence display device according to an embodiment of the present specification.

Referring to FIG. 2 , the pixel of the electroluminescent display device 200 includes a switching transistor 240, a driving transistor 250, a compensation circuit 260, and a light emitting element 270.

The light emitting element 270 operates to emit light according to the driving current generated by the driving transistor 250.

The switching transistor 240 performs a switching operation so that the data signal supplied through the data line 230 is stored as a data voltage in a capacitor in response to the gate signal supplied through the gate line 220.

The driving transistor 250 operates so that a constant driving current flows between the high-potential power line (VDD) and the low-potential power line (GND) in response to the data voltage stored in the capacitor.

The compensation circuit 260 is a circuit for compensating the threshold voltage of the driving transistor 250, and the compensation circuit 260 includes one or more thin film transistors and a capacitor. The composition of the compensation circuit may vary depending on the compensation method.

In addition, the pixel of the electroluminescent display device 200 is composed of a 2T (Transistor) 1C (Capacitor) structure including a switching transistor 240, a driving transistor 250, a capacitor, and a light emitting element 270, but a compensation circuit ( 260) is added, it can be formed in various ways, such as 3T1C, 4T2C, 5T2C, 6T1C, 6T2C, 7T1C, 7T2C, etc.

Figure 3 is a plan view of an electroluminescence display device according to an embodiment of the present specification. In detail, the flexible substrate 310 of the flexible electroluminescent display device 300 is not bent.

Referring to FIG. 3, the flexible electroluminescent display device 300 has a display area (Active Area (A/A)) and a display area in which pixels that actually emit light through thin film transistors and light emitting elements are arranged on a flexible substrate 310. Includes a non-active area (N/A) surrounding the outer edge of the area (A/A).

The non-display area (N/A) of the flexible substrate 310 includes circuits such as the gate driver 390 for driving the flexible electroluminescent display device 300 and various signals such as scan lines (S/L). Wiring may be placed. In addition, the circuit for driving the flexible electroluminescent display device 300 is arranged as a GIP (Gate in Panel) on the substrate 310, or is mounted on a flexible substrate (Tape Carrier Package) (TCP) or Chip on Film (COF) method. 310).

A pad 395 is disposed on one side of the substrate 505 in the non-display area (N/A). Pad 395 is a metal pattern bonded to an external module.

A bending area (B/A) can be formed by bending a portion of the non-display area (N/A) of the flexible substrate 310 in the bending direction as indicated by the arrow. The non-display area (N/A) of the flexible substrate 310 has wiring and driving circuits for driving the screen, and is not an area where images are displayed, so it does not need to be visible from the top of the flexible substrate 310. . Accordingly, by bending a portion of the non-display area (N/A) of the flexible substrate 310, the bezel area can be reduced while securing an area for wiring and driving circuits.

Various wiring lines are formed on the flexible substrate 310. Wiring may be formed in the display area (A/A) of the substrate 310. Alternatively, the circuit wiring 370 formed in the non-display area (N/A) can transmit signals by connecting a driving circuit, a gate driver, and a data driver.

The circuit wiring 370 is made of a conductive material and may be made of a conductive material with excellent ductility to reduce the occurrence of cracks when bending the substrate 310. For example, the circuit wiring 370 may be formed of a conductive material with excellent ductility, such as gold (Au), silver (Ag), aluminum (Al), and various conductive materials used in the display area (A/A). It can be formed of one of molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), and an alloy of silver (Ag) and magnesium (Mg), etc. It may also be composed of: In addition, the circuit wiring 370 may be composed of a multi-layer structure containing various conductive materials, for example, a three-layer structure of titanium (Ti)/aluminum (Al)/titanium (Ti). It is not limited.

The circuit wiring 370 formed in the bending area (B/A) receives a tensile force when bent. For example, the circuit wiring 370 extending in the same direction as the bending direction (indicated by an arrow) on the flexible substrate 310 is subjected to the greatest tensile force, which may cause cracks. If the cracks are severe, disconnection may occur. there is. Therefore, rather than forming the circuit wiring 370 to extend in the bending direction, at least a portion of the circuit wiring 370 disposed including the bending area (B/A) extends in a diagonal direction that is different from the bending direction. By forming it, the tensile force can be minimized and the occurrence of cracks can be minimized.

The circuit wiring 370 disposed including the bending area (B/A) may be formed in various shapes, for example, trapezoidal wave shape, triangle wave shape, sawtooth wave shape, sinusoidal wave shape, omega (Ω) shape, and rhombus shape. It can be formed in various shapes, such as shape.

4A and 4B are cross-sectional views of detailed structures of a display area and a bending area of an electroluminescence display device according to an embodiment of the present specification.

FIG. 4A is a cross-sectional view of the display area (A/A) described in FIG. 3.

Referring to FIG. 4A, the substrate 405 serves to support and protect the components of the electroluminescent display device 400 disposed on the top, and recently, it can be made of a soft material with flexible characteristics. , the substrate 405 may be a flexible substrate. For example, the flexible substrate may be in the form of a film containing one of the group consisting of polyester-based polymer, silicon-based polymer, acrylic polymer, polyolefin-based polymer, and copolymers thereof.

For example, the substrate 405 may be made of polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polysilane, polysiloxane, polysilazane, polycarbosilane, polyacrylate, polymethacrylate, polymethylacrylate, polymethylmethacrylate, polyethylacrylate, polyethylmethacrylate, between Click olefin copolymer (COC), cyclic olefin polymer (COP), polyethylene (PE), polypropylene (PP), polyimide (PI), polymethyl methacrylate (PMMA), polystyrene (PS), polyacetal ( POM), polyetheretherketone (PEEK), polyestersulfone (PES), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), polycarbonate (PC), polyvinylidene fluoride (PVDF), purple It may be composed of at least one of fluoroalkyl polymer (PFA), styrene acryl nitrile copolymer (SAN), and combinations thereof.

Then, the first buffer layer 412 and the second buffer layer 414 are disposed on the substrate 405. The first and second buffer layers 412 and 414, which are composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx), prevent moisture or other impurities from penetrating through the substrate 405, and the substrate ( 405) can be flattened. The first and second buffer layers 412 and 414 are not absolutely necessary and may be omitted depending on the type of substrate 405 or the type of thin film transistor 420 disposed on the substrate 405.

A shield layer 410 is disposed on the first buffer layer 412. The shield layer 410 is made of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), and neodymium (Nd). It can be composed of a metal material or an alloy thereof, a single layer or multiple layers, and is placed between the substrate 405 and the semiconductor layer 428 to overlap the semiconductor layer 428.

By applying power to the shield layer 410, the electrical characteristics of the thin film transistor can be prevented from changing. When power is applied to the shield layer 410, the electric field generated by the flexible substrate 405 below the semiconductor layer 428 can be shielded to prevent the characteristics of the thin film transistor 420 from changing. At this time, as a method of applying power, source power can be applied to the shield layer 410 by connecting the source electrode 424 of the thin film transistor 420 and the shield layer 410 in each pixel. The connection structure of the source electrode 424 and the shield layer 410 will be described in detail in FIGS. 5A and 5B.

A second buffer layer 414 is disposed on the shield layer 410, and the thin film transistor 420 disposed on the second buffer layer 414 includes a gate electrode 422, a source electrode 424, and a drain electrode 426. and a semiconductor layer 428.

The semiconductor layer 428 is made of amorphous silicon or polycrystalline silicon, which has better mobility than amorphous silicon, has low energy consumption and excellent reliability, and can be applied to a driving thin film transistor within a pixel. ), but is not limited to this.

The semiconductor layer 428 can be made of an oxide semiconductor, and oxide semiconductors have excellent mobility and uniformity properties. Oxide semiconductors include indium tin gallium zinc oxide (InSnGaZnO)-based materials, which are quaternary metal oxides, indium gallium zinc oxide (InGaZnO)-based materials, which are ternary metal oxides, indium tin zinc oxide (InSnZnO)-based materials, and indium aluminum zinc oxide (InAlZnO). )-based materials, tin gallium zinc oxide (SnGaZnO)-based materials, aluminum gallium zinc oxide (AlGaZnO)-based materials, tin aluminum zinc oxide (SnAlZnO)-based materials, indium zinc oxide (InZnO)-based materials, which are binary metal oxides, tin-zinc Oxide (SnZnO) based material, aluminum zinc oxide (AlZnO) based material, zinc magnesium oxide (ZnMgO) based material, tin magnesium oxide (SnMgO) based material, indium magnesium oxide (InMgO) based material, indium gallium oxide (InGaO) based material The semiconductor layer 428 can be formed of indium oxide (InO)-based materials, tin oxide (SnO)-based materials, zinc oxide (ZnO)-based materials, etc., and the composition ratio of each element is not limited.

The semiconductor layer 428 may include a source region containing p-type or n-type impurities, a drain region, and a channel between the source region and the drain region. A low-concentration doping region may be included between adjacent source and drain regions.

The source region and drain region are regions doped with impurities at a high concentration, and are regions where the source electrode 424 and drain electrode 426 of the thin film transistor 420 are connected, respectively. The impurity ion may be a p-type impurity or an n-type impurity. The p-type impurity may be one of boron (B), aluminum (Al), gallium (Ga), and indium (In), and the n-type impurity may be phosphorus ( It may be one of P), arsenic (As), antimony (Sb), etc.

The semiconductor layer 428 may be doped with an n-type impurity or a p-type impurity in the channel region depending on the thin film transistor structure of NMOS or PMOS, and the thin film transistor included in the electroluminescent display device according to the embodiment of the present specification is NMOS. Alternatively, PMOS thin film transistors are applicable.

The first insulating layer 431 is an insulating layer composed of a single layer of silicon oxide (SiOx) or silicon nitride (SiNx) or multiple layers thereof, and prevents the current flowing in the semiconductor layer 428 from flowing to the gate electrode 422. Arrange so that it does not occur. In addition, silicon oxide is less ductile than metal, but has superior ductility than silicon nitride and can be selectively formed as a single layer or multiple layers depending on its characteristics.

The gate electrode 422 serves as a switch to turn on or off the thin film transistor 420 based on an external electrical signal transmitted through the gate line, and is made of a conductive metal. Single layer of copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), and neodymium (Nd), or alloys thereof. Alternatively, it may be composed of multiple layers, but is not limited thereto.

The source electrode 424 and the drain electrode 426 are connected to the data line and allow electrical signals transmitted from the outside to be transmitted from the thin film transistor 420 to the light emitting device 440. The source electrode 424 and the drain electrode 426 are made of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), It may be composed of a single layer or multiple layers of metal materials such as neodymium (Nd) or alloys thereof, but is not limited thereto.

In order to insulate the gate electrode 422, the source electrode 424, and the drain electrode 426 from each other, a second insulating layer 433 composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx) is formed on the gate. It can be placed between the electrode 422, the source electrode 424, and the drain electrode 426.

A passivation layer made of an inorganic insulating layer such as silicon oxide (SiOx) or silicon nitride (SiNx) may be further disposed on the thin film transistor 420. The passivation layer can prevent unnecessary electrical connections between passivation layer components and prevent contamination or damage from the outside, and may be omitted depending on the configuration and characteristics of the thin film transistor 420 and the light emitting device 440. You may.

The thin film transistor 420 can be classified into an inverted staggered structure and a coplanar structure depending on the positions of the components constituting the thin film transistor 420. In an inverted staggered thin film transistor, the gate electrode is located on the opposite side of the source electrode and drain electrode based on the semiconductor layer. As shown in FIG. 4A, in the thin film transistor 420 having a coplanar structure, the gate electrode 422 is located on the same side as the source electrode 424 and the drain electrode 426 with respect to the semiconductor layer 428.

Although FIG. 4A shows a thin film transistor 420 having a coplanar structure, the electroluminescent display device 400 may also include a thin film transistor having an inverted staggered structure.

For convenience of explanation, only the driving thin film transistor is shown among the various thin film transistors that may be included in the electroluminescent display device 400, but switching thin film transistors, capacitors, etc. may also be included in the electroluminescent display device 400. At this time, when a signal is applied from the gate wiring, the switching thin film transistor transfers the signal from the data wiring to the gate electrode of the driving thin film transistor. The driving thin film transistor transmits the current transmitted through the power wiring by a signal received from the switching thin film transistor to the anode 442, and controls light emission by the current transmitted to the anode 442.

Protects the thin film transistor 420, alleviates the step difference caused by the thin film transistor 420, and reduces parasitic capacitance generated between the thin film transistor 420, the gate line, the data line, and the light emitting device 440. In order to reduce capacitance, planarization layers 435 and 437 are disposed on the thin film transistor 420.

The planarization layers 435 and 437 are made of acrylic resin, epoxy resin, phenolic resin, polyamides resin, polyimides resin, and unsaturated polyester. It may be formed of one or more of Unsaturated Polyesters Resin, Polyphenylene Resin, Polyphenylenesulfides Resin, and Benzocyclobutene, but is not limited thereto.

The electroluminescent display device 400 according to an embodiment of the present specification may include a first planarization layer 435 and a second planarization layer 437, which are a plurality of planarization layers 435 and 437 sequentially stacked.

For example, the first planarization layer 435 may be stacked and disposed on the thin film transistor 420, and the second planarization layer 437 may be sequentially stacked on the first planarization layer 435.

Additionally, a buffer layer may be disposed on the first planarization layer 435. The buffer layer is disposed to protect the components disposed on the first planarization layer 435, and is a single layer of silicon nitride (SiNx) or silicon oxide (SiOx) or a multilayer of silicon nitride (SiNx) or silicon oxide (SiOx). It may be composed of layers, and may be omitted depending on the configuration and characteristics of the thin film transistor 420 and the light emitting device 440.

The intermediate electrode 430 is connected to the thin film transistor 420 through a contact hole formed in the first planarization layer 435. The intermediate electrode 430 may be formed to be connected to the thin film transistor 420.

In addition, the data line may be formed in a structure in which a lower layer made of the same material as the source electrode 424 and the drain electrode 426 and a layer made of the same material as the middle electrode 430 are connected, so that the two layers are parallel to each other. Since the data line can be implemented in a connected structure, the wiring resistance of the data line can be reduced.

A passivation layer made of an inorganic insulating layer such as silicon oxide (SiOx) or silicon nitride (SiNx) may be further disposed on the first planarization layer 435 and the intermediate electrode 430. The passivation layer may serve to prevent unnecessary electrical connections between components and prevent contamination or damage from the outside, and may be omitted depending on the configuration and characteristics of the thin film transistor 420 and the light emitting device 440.

The light emitting device 440 disposed on the second planarization layer 437 includes an anode 442, a light emitting portion 444, and a cathode 446.

The anode 442 may be disposed on the second planarization layer 437. The anode 442 is an electrode that supplies holes to the light emitting unit 444, and is connected to the intermediate electrode 430 through a contact hole in the second planarization layer 437, and is electrically connected to the thin film transistor 420. It is connected to

The anode 442 may be made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO), but is not limited thereto.

When the electroluminescent display device 400 is a top emission device that emits light toward the top where the cathode 446 is disposed, the emitted light is reflected from the anode 442 to more smoothly reach the cathode 446. It may further include a reflective layer so that it can be emitted in the upper direction where it is disposed.

For example, the anode 442 may have a two-layer structure in which a transparent conductive layer made of a transparent conductive material and a reflective layer are sequentially stacked, or it may have a three-layer structure in which a transparent conductive layer, a reflective layer, and a transparent conductive layer are sequentially stacked, and the reflective layer is It may be silver (Ag) or an alloy containing silver.

The bank 450 disposed on the anode 442 and the second planarization layer 437 may define a pixel by dividing an area that actually emits light. After forming photoresist on the anode 442, the bank 450 is formed by photolithography. Photoresist refers to a photosensitive resin whose solubility in a developer changes under the action of light, and a specific pattern can be obtained by exposing and developing the photoresist. Photoresist can be classified into positive photoresist and negative photoresist. Positive photoresist refers to a photoresist whose solubility in the developer of the exposed area increases with exposure. When a positive photoresist is developed, a pattern with the exposed area removed is obtained. In addition, negative photoresist refers to a photoresist whose solubility in the developer of the exposed area is greatly reduced by exposure. When the negative photoresist is developed, a pattern with the non-exposed area removed is obtained.

To form the light emitting portion 444 of the light emitting device 440, a fine metal mask (FMM), which is a deposition mask, can be used. In addition, in order to prevent damage that may occur by contact with the deposition mask disposed on the bank 450 and to maintain a constant distance between the bank 450 and the deposition mask, a transparent organic polyethylene layer is placed on the top of the bank 450. A spacer (452) composed of one of mead, photoacrylic, and benzocyclobutene (BCB) may be placed.

A light emitting unit 444 is disposed between the anode 442 and the cathode 446. The light emitting part 444 serves to emit light, and includes a hole injection layer (HIL), a hole transport layer (HTL), a light emitting layer, an electron transport layer (ETL), and an electron injection layer. (Electron Injection Layer; EIL), and some components of the light emitting unit 444 may be omitted depending on the structure or characteristics of the electroluminescence display device 400. Here, it is also possible to apply an electroluminescent layer or an inorganic light emitting layer as the light emitting layer.

The hole injection layer is disposed on the anode 442 to facilitate hole injection. The hole injection layer is, for example, HAT-CN (dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10.11-hexacarbonitrile), CuPc (phthalocyanine), and It may be composed of one or more of NPD (N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-2,2'-dimethylbenzidine).

The hole transport layer is disposed on the hole injection layer and serves to smoothly transfer holes to the light emitting layer. The hole transport layer is, for example, NPD (N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-2,2'-dimethylbenzidine), TPD(N,N'-bis -(3-methylphenyl)-N,N'-bis-(phenyl)-benzidine), s-TAD(2,2',7,7'-tetrakis(N,N-dimethylamino)-9,9-spirofluorene) , and MTDATA (4,4',4"-Tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine).

The light-emitting layer is disposed on the hole transport layer and can emit light of a specific color by including a material that can emit light of a specific color. Also, the light-emitting material can be formed using a phosphorescent material or a fluorescent material.

When the light-emitting layer emits red, the peak wavelength of light emission may be in the range of 600 nm to 650 nm, and CBP (4,4'-bis(carbazol-9-yl)biphenyl) or mCP (1,3 -Contains host materials including bis(carbazol-9-yl)benzene), PIQIr(acac)(bis(1-phenylisoquinoline)(acetylacetonate) iridium), PQIr(acac)(bis(1-phenylquinoline)(acetylacetonate) ) iridium), tris(1-phenylquinoline) iridium (PQIr), and octaethylporphyrin platinum (PtOEP). Alternatively, it may be made of a fluorescent material containing PBD:Eu(DBM)3(Phen) or Perylene.

Here, the peak wavelength (λ) refers to the maximum wavelength of EL (ElectroLuminescence). The wavelength at which the light-emitting layers that make up the light emitting part emit their own light is called PL (PhotoLuminescence), and the effect of the thickness or optical properties of the layers that make up the light emitting layers is called PL (PhotoLuminescence). The light received and emitted is called emittance. At this time, EL (ElectroLuminescence) refers to the light finally emitted by the electroluminescence display device, and can be expressed as the product of PL (PhotoLuminescence) and emittance.

When the light emitting layer emits green, the peak wavelength of light emission may be in the range of 520 nm to 540 nm, and includes a host material containing CBP or mCP, and Ir(ppy) ₃ (tris(2-phenylpyridine)iridium ) may be made of a phosphorescent material containing a dopant material such as an Ir complex containing. Additionally, it may be made of a fluorescent material containing Alq ₃ (tris(8-hydroxyquinolino)aluminum).

When the light emitting layer emits blue, the peak wavelength of light emission may be in the range of 440 nm to 480 nm, contains a host material containing CBP or mCP, and FIrPic (bis(3,5-difluoro-2 It may be made of a phosphorescent material containing a dopant material containing -(2-pyridyl)phenyl-(2-carboxypyridyl)iridium). In addition, spiro-DPVBi(4,4'-Bis(2,2-diphenyl-ethen) -1-yl)biphenyl), DSA (1-4-di-[4-(N,N-di-phenyl)amino]styryl-benzene), PFO (polyfluorene) polymer, and PPV (polyphenylenevinylene) polymer. It may be made of a fluorescent material containing one.

An electron transport layer is placed on the light emitting layer to facilitate the movement of electrons to the light emitting layer. The electron transport layer is, for example, Liq (8-hydroxyquinolinolato-lithium), PBD (2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), TAZ (3- (4-biphenyl)4-phenyl-5-tert-butylphenyl-1,2,4-triazole), spiro-PBD, BCP(2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline) and BAlq (bis(2-methyl-8-quinolinolate)-4-(phenylphenolato)aluminum).

An electron injection layer may be further disposed on the electron transport layer. The electron injection layer is an organic layer that facilitates injection of electrons from the cathode 446, and may be omitted depending on the structure and characteristics of the electroluminescence display device 400. The electron injection layer may be a metal inorganic compound such as BaF2, LiF, NaCl, CsF, _Li2O and BaO, and HAT-CN (dipyrazino[2,3-f:2',3'-h]quinoxaline-2, 3,6,7,10.11-hexacarbonitrile), CuPc (phthalocyanine), and NPD (N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-2,2'-dimethylbenzidine) It may be any one or more organic compounds.

An electron blocking layer or hole blocking layer is further placed adjacent to the light emitting layer to block the flow of holes or electrons, so that when electrons are injected into the light emitting layer, they move from the light emitting layer and pass through the adjacent hole transport layer. When holes are injected into the light-emitting layer, the luminous efficiency can be improved by preventing the hole from moving from the light-emitting layer and passing through the adjacent electron transport layer.

The cathode 446 is disposed on the light emitting unit 444 and serves to supply electrons to the light emitting unit 444. Since the cathode 446 must supply electrons, it can be made of a metal material such as magnesium (Mg) or silver-magnesium (Ag:Mg), which is a conductive material with a low work function, but is not limited thereto.

When the electroluminescent display device 400 is a top emission type, the cathode 446 is made of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), and zinc oxide ( It may be a transparent conductive oxide of the Zinc Oxide (ZnO) and Tin Oxide (TiO) series.

A bag is placed on the light emitting device 440 to prevent the thin film transistor 420 and the light emitting device 440, which are components of the electroluminescence display device 400, from being oxidized or damaged due to moisture, oxygen, or impurities flowing in from the outside. The portion 460 can be disposed and formed by stacking a plurality of encapsulation layers, a foreign matter compensation layer, and a plurality of barrier films.

The encapsulation layer is disposed on the entire upper surface of the thin film transistor 420 and the light emitting device 440, and may be made of one of inorganic silicon nitride (SiNx) or aluminum oxide (AlyOz), but is not limited thereto.

An encapsulation layer may be further disposed on the foreign matter compensation layer disposed on the encapsulation layer.

The foreign matter compensation layer is placed on the encapsulation layer, and can use organic silicon oxycarbon (SiOCz), acryl, or epoxy-based resin, but is not limited to this, and may be generated during the process. When defects occur due to cracks caused by foreign matter or particles, the bending and foreign matter can be covered by the foreign matter compensation layer to compensate.

By disposing a barrier film on the encapsulation layer and the foreign matter compensation layer, the electroluminescent display device 400 can delay the infiltration of oxygen and moisture from the outside. The barrier film is composed of a light-transmitting and double-sided adhesive film, and can be made of any one of the following insulating materials: Olefin-based, Acrylic-based, and Silicon-based, or COP (Cyclolefin). A barrier film made of any one of materials such as polymer), COC (cycloolefin copolymer), and PC (polycarbonate) can be further laminated, but is not limited thereto.

FIG. 4B is a cross-sectional view of the bending area (B/A) described in FIG. 3.

Some components of FIG. 4B are substantially the same/similar to the components described in FIG. 4A and detailed description thereof will be omitted.

The gate signal and data signal described in FIGS. 1 to 3 pass from the outside through circuit wiring disposed in the non-display area (N/A) of the electroluminescent display device 400 to the pixels disposed in the display area (A/A). It is transmitted to and emits light.

When the wires disposed in the non-display area (N/A) including the bending area (B/A) of the electroluminescent display device 400 are formed in a single layer structure, a large amount of space is required to place the wires. After depositing a conductive material, the conductive material is patterned into the shape of the wire to be formed through a process such as etching. However, since the precision of the etching process is limited, a lot of space is required due to the limitation of narrowing the gap between wires. As the area of the non-display area (N/A) increases, difficulties may arise in implementing a narrow bezel.

Additionally, when one wire is used to transmit one signal, if the wire is cracked, the signal may not be transmitted. In the process of bending the substrate 405, cracks may occur in the wiring itself, or cracks may occur in other layers and the cracks may propagate to the wiring. Likewise, if a crack occurs in the wiring, the transmitted signal may not be transmitted.

Accordingly, the wiring disposed in the bending area (B/A) of the electroluminescent display device 400 according to the embodiment of the present specification is arranged in the form of a double wiring of the first wiring 462 and the second wiring 464. .

The first wiring 462 and the second wiring 464 are made of a conductive material, and may be made of a conductive material with excellent ductility to reduce the occurrence of cracks when bending the flexible substrate 405. The first wiring 462 and the second wiring 464 may be formed of a conductive material with excellent ductility, such as gold (Au), silver (Ag), aluminum (Al), etc., and the display area (A/ A) It can be formed from one of the various conductive materials used in molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), and silver (Ag). It may also be composed of an alloy of and magnesium (Mg). In addition, the first wiring 462 and the second wiring 464 may be composed of a multilayer structure containing various conductive materials, for example, titanium (Ti)/aluminum (Al)/titanium (Ti) 3 It may be composed of a layered structure, but is not limited thereto.

In order to protect the first wiring 462 and the second wiring 464, a buffer layer made of an inorganic insulating layer may be disposed under the first wiring 462 and the second wiring 464, and the first wiring 462 ) and a passivation layer made of an inorganic insulating layer is formed to surround the top and sides of the second wiring 464 to prevent phenomena such as corrosion of the first wiring 462 and the second wiring 464 by reacting with moisture, etc. It could be.

The first wiring 462 and the second wiring 464 formed in the bending area B/A are subjected to a tensile force when bent. As explained in FIG. 3, the wiring extending in the same direction as the bending direction on the substrate 405 receives the greatest tensile force, and cracks may occur. If the cracks are severe, wire breakage may occur. Therefore, rather than forming the wiring to extend in the bending direction, at least a portion of the wiring arranged including the bending area (B/A) is formed to extend in a diagonal direction that is different from the bending direction, thereby minimizing the tensile force and cracking. occurrence can be reduced. The shape of the wiring may be a diamond shape, a triangular wave shape, a sinusoidal shape, a trapezoid shape, etc., but is not limited thereto.

A first wiring 462 is disposed on the substrate 405 and a first planarization layer 435 is disposed on the first wiring 462. A second wiring 464 is disposed on the first planarization layer 435, and a second planarization layer 437 is disposed on the second wiring 464.

The first planarization layer 435 and the second planarization layer 437 are made of acrylic resin, epoxy resin, phenolic resin, polyamides resin, and polyimide resin. (Polyimides Resin), Unsaturated Polyesters Resin, Polyphenylene Resin, Polyphenylenesulfides Resin, and Benzocyclobutene. may, but is not limited to this.

A micro coating layer (Micro Coating Layer) 466 is disposed on the second planarization layer 437. The micro coating layer 466 protects the wiring by coating it with a thin layer of resin at the bending position because tensile force may be applied to the wiring portion disposed on the substrate 405 during bending, which may cause fine cracks. can play a role.

5A and 5B are cross-sectional views of the shield layer connection structure included in the electroluminescence display device according to the first and second embodiments of the present specification.

Figure 5a shows a structure in which the shield layer 510 and the source electrode 524 are electrically connected through the gate bridge 522, and Figure 5b shows a structure in which the shield layer 510 is directly connected to the source electrode 524. Depending on the structure or characteristics of the electroluminescent display device, one of the two structures can be selectively arranged.

The main components of the electroluminescent display shown in FIGS. 5A and 5B are substantially the same as or similar to the main components described in FIGS. 1 to 4B, and overlapping structures are omitted.

Referring to FIG. 5A, the substrate 505, which has flexible characteristics such as polyimide, is composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx) to prevent moisture, etc. from penetrating from the outside. The first buffer layer 512 and the second buffer layer 514 are sequentially stacked and disposed.

A shield layer 510 is disposed on the first buffer layer 512 to minimize the influence of the semiconductor layer 528 from charges generated from the flexible substrate 505. The shield layer 510 is made of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), and neodymium (Nd). It can be composed of metal materials or alloys thereof, single layer or multiple layers. The shield layer 510 is disposed between the substrate 505 and the semiconductor layer 528 to overlap the semiconductor layer 528 .

The second buffer layer 514 and the semiconductor layer 528 are sequentially stacked and disposed on the shield layer 510.

The semiconductor layer 528 may be made of amorphous silicon, polycrystalline silicon with better mobility than amorphous silicon, or an oxide semiconductor such as ZnO or IGZO with excellent mobility and uniformity characteristics.

The semiconductor layer 528 includes a source region and a drain region containing p-type or n-type impurities and a channel between them, and may further include a low-concentration doped region between the source region and drain region adjacent to the channel. .

A first insulating layer 531 composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx) is disposed on the semiconductor layer 528.

A gate bridge 522 made of the same layer as the gate electrode of the thin film transistor is disposed on the first insulating layer 531 in an area overlapping the shield layer 522. The gate bridge 522 is spaced apart from the gate electrode and is directly connected to the shield layer 510 through a contact hole formed in the second buffer layer 514 and the first insulating layer 531. The gate bridge 522 may be a connection electrode.

A second insulating layer 533 may be disposed on the gate electrode and gate bridge 522 to insulate the source electrode 524.

A source electrode 524 connected to the semiconductor layer 528 is disposed on the second insulating layer 533.

The source electrode 524 serves to transmit electrical signals transmitted from the outside from the thin film transistor to the electroluminescent device, and is made of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), and gold. (Au), titanium (Ti), nickel (Ni), and neodymium (Nd), etc. or alloys thereof, and can be composed of a single layer or multiple layers.

The source electrode 524 is directly connected to the gate bridge 522 through a contact hole formed in the second insulating layer 533. Through this, the source electrode 524 and the shield layer 510 are electrically connected to each other, thereby minimizing the influence of the flexible substrate 505 on the semiconductor layer 528 disposed on the shield layer 510.

A planarization layer 535 is formed on the source electrode 524, and other main components of the electroluminescence display device on the planarization layer 535 are substantially the same or similar to the main components described in FIGS. 4A to 4B. .

Referring to Figure 5b, the substrate 505, which has flexible characteristics such as polyimide, is composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx) to prevent moisture, etc. from penetrating from the outside. The first buffer layer 512 and the second buffer layer 514 may be sequentially stacked and disposed. Additionally, the buffer layer may be omitted depending on the structure or characteristics of the electroluminescent display device.

A shield layer 510 is disposed on the first buffer layer 512 to minimize the influence of the semiconductor layer 528 from charges generated from the flexible substrate 505. The shield layer 510 is made of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), and neodymium (Nd). It can be composed of a metal material or an alloy thereof, a single layer or multiple layers. The shield layer 510 is disposed between the substrate 505 and the semiconductor layer 528 to overlap the semiconductor layer 528 .

A second buffer layer 514 on the shield layer 510 and a semiconductor layer (528) that can be made of amorphous silicon, polycrystalline silicon with better mobility than amorphous silicon, or an oxide semiconductor such as ZnO or IGZO with excellent mobility and uniformity characteristics. ) are stacked and placed sequentially.

The semiconductor layer 528 includes a source region and a drain region containing p-type or n-type impurities and a channel between them, and may further include a low-concentration doped region between the source region and drain region adjacent to the channel. there is.

A first insulating layer 531 and a second insulating layer 533 composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx) are sequentially disposed on the semiconductor layer 528.

A source electrode 524 is disposed on the second insulating layer 533, which is connected to the semiconductor layer 528 and serves to transmit an external electrical signal from the thin film transistor to the electroluminescent device.

The source electrode 524 is connected to the semiconductor layer 528 through a contact hole that penetrates the second buffer layer 514, the semiconductor layer 528, the first insulating layer 531, and the second insulating layer 533. and is simultaneously connected to the shield layer 510. Through this, the source electrode 324 and the shield layer 510 are electrically connected to each other, thereby minimizing the influence of the flexible substrate 505 on the semiconductor layer 528 disposed on the shield layer 510.

A planarization layer 535 is formed on the source electrode 524, and other main components of the electroluminescence display device on the planarization layer 535 are substantially the same or similar to the main components described in FIGS. 4A to 4B. .

6A to 6D illustrate the manufacturing process of the shield layer connection structure included in the electroluminescence display device according to the second embodiment of the present specification.

The main components of the flexible electroluminescence display shown in FIGS. 6A to 6C are substantially the same as or similar to the main components described in FIGS. 1 to 5B, and overlapping components are omitted.

Referring to FIG. 6A, a first buffer layer 612 is deposited as a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx) on the substrate 605, and a metal layer is deposited. A mask is placed on the deposited metal layer and patterned to form a shield layer 610. And, the shield layer 610 is overlapped with the semiconductor layer 528 disposed on top.

Referring to FIG. 6B, a second buffer layer 614 is deposited on the shield layer 610, a semiconductor material is deposited on the second buffer layer 614, and patterned with a mask to form a semiconductor layer 628.

Referring to FIG. 6C, a first insulating layer 631 is deposited on the semiconductor layer 628. As explained in FIGS. 5A and 5B, in the electroluminescence display device according to the first embodiment of the present specification, a separate layer penetrating the second buffer layer 614 and the first insulating layer 631 is used to connect the gate bridge and the shield layer. Although a contact hole is formed, in the electroluminescent display device according to the second embodiment of the present specification, a separate contact hole penetrating the second buffer layer 614 and the first insulating layer 631 is not formed, so the manufacturing process is There is a simplification effect.

A second insulating layer 633 is deposited on the first insulating layer 631, and the first insulating layer 631, the second insulating layer 633, the semiconductor layer 628, and the second insulating layer 633 are deposited on the first insulating layer 631. A contact hole is formed through which the upper part of the shield layer 610 is exposed through the buffer layer 614.

Referring to FIG. 6D, a conductive metal layer is deposited on the second insulating layer 633 and patterned with a mask to form a source electrode 624, and is connected to the semiconductor layer 628 through a contact hole while simultaneously forming a shield layer 610. ), the influence of the semiconductor layer 618 disposed on the shield layer 610 from the charge of the substrate 605 can be minimized.

Manufacturing processes for other main components of the electroluminescent display device on the source electrode 624 are substantially the same as or similar to the main components described in FIGS. 4A to 5B and are omitted.

Figure 7 is a cross-sectional view of a bending area of a flexible electroluminescent display device according to an embodiment of the present specification.

Referring to FIG. 7, a barrier film 720 is disposed on the flexible substrate 710. The barrier film 720 is a component for protecting various components of the flexible electroluminescent display device 700, and may be arranged to correspond to at least the display area (A/A) of the flexible electroluminescent display device 700.

For example, the barrier film 720 may be composed of an adhesive material, and the adhesive material may be a heat-curing or natural-curing adhesive, or a material such as PSA (Pressure Sensitive Adhesive). It can be configured to play a role in fixing the polarizer 730 on the barrier film 720.

The polarizer 730 disposed on the barrier film 720 suppresses reflection of external light on the display area (A/A). When the display device 700 is used outside, external natural light may flow in and be reflected by a reflector included in the anode of the electroluminescent device or by an electrode made of metal disposed below the organic light emitting device. The image of the display device 700 may not be clearly visible due to the reflected lights. The polarizer 730 polarizes light introduced from the outside in a specific direction and prevents the reflected light from being emitted outside of the display device 700 again. The polarizer 730 may be disposed on the display area A/A, but is not limited thereto.

The polarizing plate 730 may be a polarizing plate composed of a polarizer and a protective film that protects it, or may be formed by coating a polarizing material for flexibility.

A cover glass (CG) that protects the exterior of the display device 700 may be placed by placing an adhesive layer on the polarizing plate 730.

A back plate 740 is disposed below the flexible substrate 710. When the flexible substrate 710 is made of a plastic material such as polyimide, the manufacturing process of the flexible electroluminescent display device 700 proceeds with a support substrate made of glass placed below the flexible substrate 710, and the manufacturing process proceeds. After completion, the support substrate can be separated and released.

Since components are needed to support the flexible substrate 710 even after the support substrate is released, a backplate 740 for supporting the flexible substrate 505 may be disposed below the flexible substrate 710. The backplate 740 may be disposed adjacent to the bending area (B/A) in other areas of the flexible substrate 505 except for the bending area (B/A).

The backplate 740 may be made of a plastic thin film formed of polyimide, polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polymers, or a combination of these polymers.

A support member 770 is disposed between the two back plates 740, and the support member 770 may be adhered to the back plate 740 by an adhesive layer 760. The support member 570 may be formed of a plastic material such as polycarbonate (PC), polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polymers, combinations of these polymers, etc. The strength of the support member 770 formed from these plastic materials may be controlled by adding additives to increase the thickness and strength of the support member 770. Additionally, the support member 770 may be formed of glass, ceramic, metal, or other rigid materials or a combination of the above materials.

A micro coating layer (Micro Coating Layer) 750 is disposed on the bending area (B/A) of the flexible substrate 710. The micro coating layer 750 may be formed to cover one side of the barrier film 720.

Since the micro coating layer 750 may generate micro cracks due to tensile force acting on the wiring portion disposed on the flexible substrate 710 during bending, resin is coated with a thin layer at the bending position to secure the wiring. It can play a protective role.

The micro coating layer 750 can adjust the neutral plane of the bending area (B/A). The neutral plane refers to a virtual surface on which no stress occurs because the compressive force and tensile force applied to the structure cancel each other out when the structure is bent. When two or more structures are stacked, a virtual neutral plane may be formed between the structures. When the entire structure is bent in one direction, the structures arranged in the bending direction with respect to the neutral plane are compressed by bending and thus receive a compressive force. On the contrary, structures placed in the direction opposite to the bending direction based on the neutral plane are stretched by bending and thus receive a tensile force. At this time, structures are generally more vulnerable when subjected to tensile force among the same compressive force and tensile force, so the probability of cracks occurring when subjected to tensile force is higher.

The flexible substrate 710 disposed below the neutral plane is compressed and thus receives a compressive force, and the wiring disposed on the upper portion may receive a tensile force, and thus cracks may occur due to the tensile force. Therefore, in order to minimize the tension on the wiring, it can be located on the neutral plane.

By placing the micro coating layer 750 on the bending area (B/A), the neutral plane can be raised upward, and the neutral plane can be formed at the same position as the wiring or located at a higher position than the neutral plane to reduce stress during bending. The occurrence of cracks can be suppressed by not being exposed to compressive force.

The micro coating layer 750 may be made of resin, an acrylic material, or urethane acrylate, but is not limited thereto.

An insulating film 780 is connected to the end of the flexible substrate 710. Various wirings are formed on the insulating film 780 to transmit signals to pixels arranged in the display area (A/A). The insulating film 780 is made of a material that has flexibility so that it can be bent. A driving element may be mounted on the insulating film 780, and together with the insulating film 780, it forms a driving package such as a chip on film (COF), and is formed on the insulating film 780. It is connected to the wiring and provides driving signals and data to the pixels placed in the display area (A/A).

The circuit board connected to the insulating film 780 can receive image signals from the outside and apply various signals to the pixels arranged in the display area (A/A), and may be a printed circuit board. .

A flexible electroluminescent display device according to an embodiment of the present specification includes a shield layer on a flexible substrate, a buffer layer on the shield layer, a thin film transistor on the buffer layer, and an electroluminescent element on the thin film transistor, and the shield layer The thin film transistor has an overlapping area, and the thin film transistor and the shield layer are connected in the overlapping area.

The thin film transistor of the flexible electroluminescent display device according to the embodiment of the present specification is connected to the shield layer through a contact hole.

The thin film transistor of the flexible electroluminescent display device according to the embodiment of the present specification includes a semiconductor layer on a substrate, a first insulating layer on the semiconductor layer, a gate electrode on the first insulating layer, and a second insulating layer on the gate electrode. It includes an insulating layer, a drain electrode and a source electrode on the second insulating layer.

The contact hole of the flexible electroluminescent display device according to the embodiment of the present specification penetrates the buffer layer, the first insulating layer, the second insulating layer, and the semiconductor layer, and the source electrode and the shield layer are connected.

The contact hole of the flexible electroluminescent display device according to the embodiment of the present specification penetrates the buffer layer and the first insulating layer, and the connection electrode on the same layer as the gate electrode is connected to the shield layer.

The connection electrode of the flexible electroluminescent display device according to the embodiment of the present specification is directly connected to the source electrode.

The semiconductor layer of the flexible electroluminescent display device according to an embodiment of the present specification includes a region doped with impurities.

The impurity of the flexible electroluminescent display device according to the embodiment of the present specification is one of boron (B), aluminum (Al), gallium (Ga), and indium (In).

The impurity of the flexible electroluminescent display device according to the embodiment of the present specification is one of phosphorus (P), arsenic (As), and antimony (Sb).

The semiconductor layer of the flexible electroluminescent display device according to the embodiment of the present specification is either an oxide semiconductor layer or a polysilicon semiconductor layer.

At least one of the source electrode, drain electrode, and gate electrode of the flexible electroluminescent display device according to the embodiment of the present specification is composed of a plurality of metal layers.

A flexible electroluminescent display device according to an embodiment of the present specification includes forming a shield layer on a flexible substrate, forming a buffer layer on the shield layer, and forming a semiconductor layer, a gate electrode, a source electrode, and a drain electrode on the buffer layer. The manufacturing process includes forming a thin film transistor, forming an electroluminescent element on the thin film transistor, and the shield layer and the thin film transistor have an overlapping area, and connecting the thin film transistor and the shield layer in the overlapping area. .

The thin film transistor of the flexible electroluminescent display device according to an embodiment of the present specification includes forming a semiconductor layer on a buffer layer, forming a first insulating layer on the semiconductor layer, and forming a gate electrode on the first insulating layer. It is manufactured including the steps of forming a second insulating layer on the gate electrode, and forming a drain electrode and a source electrode on the second insulating layer.

A flexible electroluminescent display device according to an embodiment of the present specification includes forming a contact hole passing through a buffer layer, a semiconductor layer, a first insulating layer, and a second insulating layer, and forming a contact hole between a source electrode and a source electrode through the contact hole. The shield layer is manufactured to be directly connected.

A flexible electroluminescent display device according to an embodiment of the present specification includes forming a contact hole collectively penetrating a buffer layer and a first insulating layer, and forming a connection electrode on the same layer as the gate electrode, wherein the contact It is manufactured so that the connection electrode and the shield layer are connected through a hole.

It includes forming a contact hole penetrating the second insulating layer of the flexible electroluminescent display device according to an embodiment of the present specification, and manufacturing the connection electrode and the source electrode through the contact hole.

The manufacturing process further includes doping impurities into the semiconductor layer of the flexible electroluminescent display device according to an embodiment of the present specification.

Impurities in the flexible electroluminescent display device according to the embodiments of the present specification are made of one of boron (B), aluminum (Al), gallium (Ga), and indium (In).

The impurity of the flexible electroluminescent display device according to the embodiment of the present specification is made of one of phosphorus (P), arsenic (As), and antimony (Sb).

At least one of the source electrode, drain electrode, and gate electrode of the flexible electroluminescent display device according to an embodiment of the present specification is manufactured to consist of a plurality of metal layers.

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.

100, 200, 300, 400, 700: Electroluminescent display device
110: Image processing unit
120: Timing controller
130: data driver
140: gate driver
150: display panel
160: Pixels
220: Gateline
230: data line
240: switching transistor
250: Driving transistor
260: Compensation circuit
270, 440: Light emitting device
310, 405, 505, 605, 710: substrate
370: Circuit wiring
390: Gate driving part 395: Pad
410, 510, 610: shield layer
412, 512, 612: first buffer layer
414, 514, 614: second buffer layer
420: Thin film transistor
422: Gate electrode
424, 524, 624: source electrode
426: Drain electrode
428, 528, 628: semiconductor layer
431, 531, 631: first insulating layer
433, 533, 633: second insulating layer
435: first planarization layer
437: second planarization layer
442: anode
444: light emitting unit
446: cathode
450: bank
452: spacer
460: Encapsulation part
462: first wiring
464: second wiring
466, 750: Micro coating layer
522: Gatebridge
535: Flattening layer
720: Barrier film
730: Polarizer
740: Backplate
760: Adhesive layer
770: Support member
780: Circuit board
A/A: Display area
N/A: Non-display area
B/A: Bending area
S/L: scanline
C/H: Contact hole

Claims (13)

A flexible substrate including a display area and a non-display area, and forming a bending area by bending a portion of the non-display area in a bending direction;
a shield layer on the flexible substrate;
a buffer layer on the shield layer;
a thin film transistor disposed on the buffer layer;
a first planarization layer on the thin film transistor;
an intermediate electrode disposed on the first planarization layer and electrically connected to the thin film transistor;
a second planarization layer on the intermediate electrode;
an electroluminescent element disposed on the second planarization layer;
A barrier film disposed on top of the electroluminescent device;
A polarizing plate disposed on the barrier film;
a micro coating layer disposed on the flexible substrate corresponding to the bending area, spaced apart from the polarizing plate, and covering a portion of the side and top surfaces of the barrier film; and
Includes circuit wiring on the buffer layer in the bending area,
A flexible electroluminescent display device, wherein the first planarization layer and the second planarization layer are disposed in the bending area. According to claim 1,
The circuit wiring further includes a second wiring on the second planarization layer. According to clause 2,
A flexible electroluminescent display device, wherein the second wiring is on the same layer as the intermediate electrode and is made of the same material. According to clause 2,
The circuit wiring further includes a first wiring,
The first wire is disposed below the second wire,
A flexible electroluminescent display device, wherein the first wire is arranged not to overlap the second wire. According to claim 1,
First and second backplates disposed oppositely under the flexible substrate, first and second adhesive layers disposed respectively below the first and second backplates, and disposed between the first adhesive layer and the second adhesive layer. A flexible electroluminescent display device, further comprising a support member. According to clause 5,
The ends of the first and second backplates, the support member, and the first and second adhesive layers on the bending area side coincide with each other,
A flexible electroluminescent display device, wherein ends of the first backplate and the second backplate on opposite sides of the bending area are spaced apart from each other. delete According to claim 1,
It further includes an insulating film connected to an end of the flexible substrate bent in the bending direction,
A flexible electroluminescent display device, wherein the micro coating layer is extended and disposed to cover one side of the insulating film in the bending area. According to claim 1,
The thin film transistor is electrically connected to the shield layer through a contact hole. According to claim 1,
A flexible electroluminescent display device, wherein a portion of the circuit wiring disposed in the bending area extends in a diagonal direction different from the bending direction. According to claim 1,
A flexible electroluminescent display device further comprising a semiconductor layer disposed on the shield layer to overlap the shield layer. According to claim 11,
A flexible electroluminescent display device further comprising a source electrode disposed on the semiconductor layer and electrically connected to the shield layer through the semiconductor layer, and a drain electrode electrically connected to the anode of the electroluminescent device. According to claim 11,
A flexible electroluminescent display device, wherein the semiconductor layer is composed of either an oxide semiconductor layer or a polysilicon semiconductor layer.