KR20210070673A - Flexible display apparatus - Google Patents

Abstract

The flexible display device according to the exemplary embodiment of the present specification includes an active area and an inactive area, and the inactive area includes a first area adjacent to the active area, a second area on which a pad is disposed, and between the first area and the second area. There is a substrate including a bending region in the , and a wiring extending from the first region to the second region, and the wiring includes a protrusion and a groove in the bending region, thereby providing a more stable flexible display device.

Description

Flexible display device {FLEXIBLE DISPLAY APPARATUS}

The present specification relates to a flexible display device, and more particularly, to a flexible display device capable of bending a display panel.

Recently, as we enter the information age, the field of display that visually expresses electrical information signals has developed rapidly, and in response to this, various display devices (Display Apparatus) with excellent performance of thinness, light weight, and low power consumption have been developed. is being developed

Specific examples of such a display device include a Liquid Crystal Display Apparatus (LCD), an Organic Light Emitting Display Apparatus (OLED), and a Quantum Dot Display Apparatus.

The display device may include a display panel and a plurality of components for providing various functions. For example, one or more display driving circuits for controlling the display panel may be included in a display assembly. Examples of drive circuits include gate drivers, light emitting (source) drivers, power (VDD) routing, electrostatic discharge (ESD) circuits, multiplex (MUX) circuits, data signal lines, cathode contacts, and other functional element. include those A number of peripheral circuits for providing various types of additional functions, for example, touch sensing or fingerprint identification functions, may be included in the display assembly. Some components may be disposed on the display panel itself, and may be disposed on areas adjacent to the display area, which are non-display areas and/or inactive areas or non-active areas.

When designing a display device, size and weight are important issues. Also, a high ratio of the size of the active area to the size of the inactive area, referred to as the screen-to-bezel ratio, may be one of the main characteristics. However, placing some of the components described above within a display assembly may require a large inactive area, which may add up to a large portion of the display panel. A large inactive area makes the display panel large, which makes it difficult to integrate the display panel into the housing of the display device. A large inactive area may require a large masking (eg, a bezel edge, a covering material, etc.) to cover a large portion of the display panel, and may impair the aesthetics of the display device.

Some components may be disposed on a separate flexible printed circuit board (FPCB), and may be disposed on a backplane of the display panel. However, even with such a configuration, components essential for driving the display panel such as interfaces for connecting wires between the FPCB and the active region or driver ICs are still disposed in the inactive region, which may become a limit in reducing the bezel size.

The inventors of the present invention have recognized that in order to implement a narrow bezel in which the size of the inactive region is reduced, various technologies are required, including the position of the wiring, the width of the wiring, and a signal transmission method. Accordingly, the inventors of the present invention conducted various studies using the bending characteristics of the display device to which the flexible substrate is applied. Through various studies, a new structure and manufacturing method for minimizing a non-display area, for example, an inactive area, rather than an active area where an image is displayed have been invented.

For example, in order to make the display device smaller and lighter by lowering the ratio of the inactive area, a portion of the display panel may be bent to increase the ratio of the active area. This allows some inactive areas to be located behind the active areas of the display panel, thereby reducing or eliminating the inactive areas that must be masked or hidden under the housing of the display device. The bending of the display panel can minimize the size of the inactive region that must be covered from the view, realize a narrow bezel or a bezel-free display, and provide a flexible display that can improve aesthetics.

There are problems to be solved in order to implement the flexible display device, which will be described below.

Various components may be disposed directly on the flexible substrate together with the pixels of the display panel. The use of thin substrates for flexibility of flexible substrates may make components vulnerable to various mechanical and environmental stresses that may occur after manufacturing and/or completion. For example, mechanical stress due to bending of the display panel may affect the reliability of the display device, and further may cause failure of components. For example, components of wirings, such as high potential voltage (VDD) wiring, low potential voltage (VSS) wiring, and data signal lines, arranged in a region extending from the inactive region and being bent may form a flexible substrate. Deformation may occur during the bending bending process. And, during the process of attaching the flexible printed circuit board (FPCB) or light emitting (source) driver to the flexible substrate after the bending process, or during the process of bonding the display panel manufactured to the display device after attachment, the bending area of the flexible substrate Deformation of the radius of curvature (R: Radius Curvature) may occur in a specific area. Deformation of the radius of curvature may not withstand tensile stress and/or contractile stress applied to high potential voltage wirings, low potential voltage wirings, or data signal lines disposed in the corresponding region, and may cause disconnection or partial cracks. The bending region of the flexible substrate may be a bending region or a bending portion.

Accordingly, an organic passivation layer may be formed on the bending portion to protect the components from various stresses that may occur during bending. For example, an organic layer that is a micro coating layer (MCL) may be disposed on the components of the bending region. In the absence of the micro-coating layer, components on the bending area are exposed to the outside and exposed to physical impact, moisture, oxygen, etc., resulting in chemical deformation. Also, when bending, tensile stress, which relatively increases the upper surface area of the bending area, is applied to the top of the bending area. It can be strongly applied to various wirings located. The disconnection and partial cracks by this may cause a driving defect of the display panel. By disposing a micro-coating layer to protect various wirings of the bending part, it is possible to absorb physical and/or chemical shocks that may be received from the outside. By making the wirings arranged in the bending part close to the neutral plane in the laminate structure including the substrate and the micro-coating layer, less tensile stress and shrinkage stress can be applied, and the tensile stress and contraction applied to the wiring by the micro-coating layer made of organic material. By absorbing stress, defects can be reduced.

It was recognized that wirings such as data wiring, high potential voltage wiring, and low potential voltage wiring were continuously disconnected or damaged in the bending part despite the application of the micro-coating layer. For example, it has been recognized that there are cases in which damage to the wires may occur due to an impact generated during a bending process of folding a portion of the flexible substrate or a user using the display module after mounting or mounting in a process after bending.

Therefore, implementing a light and thin display device and reinforcing the rigidity of the wiring in the bending area without reinforcement of additional mechanical materials is a narrow bezel or bezel-free display device that can prevent wiring disconnection or damage that may occur before and after the bending process. can be implemented.

A display device according to an exemplary embodiment of the present specification includes an active area and an inactive area, and the inactive area includes a first area adjacent to the active area, a second area on which a pad is disposed, and a space between the first area and the second area. The substrate including the bending region and the wiring extending from the first region to the second region may include a line-shaped protrusion and a line-shaped groove in the bending region.

A display device according to an exemplary embodiment of the present specification includes a substrate including a display area and a non-display area, a light emitting display device disposed in the display area, and an encapsulation layer disposed on at least a portion of the non-display area, and disposed on the light emitting display device; The polarizing layer and the cover window disposed on the encapsulation layer, the non-display area includes a bending area, the bending area includes a bending wire extending to the light emitting display device, and the bending wire is parallel to the direction in which the bending wire extends It includes a line-shaped groove disposed, and the line-shaped groove portion may be disposed to be spaced apart from the substrate.

The details of other embodiments are included in the detailed description and drawings.

The display device according to the embodiment of the present specification applies a flexible substrate to fold all or a part of the inactive area, which is a non-display area of the display panel, into a shape having a constant radius of curvature and arrange it on the rear surface of the active area, thereby forming the entire display panel A display device having a slim bezel or a narrow bezel may be provided.

Therefore, the user of the display device can aesthetically use a device in which the light emitting screen is full on the front of the display device, and functionally, the compact module applied to the narrow bezel provides the user with an excellent grip and light weight. can provide

In the display device according to the exemplary embodiment of the present specification, the wiring disposed in the bending area may be configured as a plurality of overlapping layers. If the wiring is formed in multiple layers, a more robust wiring structure can be made against changes in the radius of curvature or external impact that may occur before/after the bending process.

In the display device according to the embodiment of the present specification, when the wiring disposed in the bending region is formed in a plurality of layers, the region of the wiring that is subjected to tensile stress and contractile stress generated for each section can be reduced or optimized, so that the disconnection occurring in the wiring Or you can reduce cracks.

In the display device according to the exemplary embodiment of the present specification, the wiring disposed in the bending region may be formed in a dome shape capable of withstanding tensile stress and contractile stress. Two dome-shaped or line-shaped grooves may be formed in the wiring to be arranged parallel to the bending direction. With such an arrangement of the wirings, it may be possible to provide wirings that can better withstand tensile stress and shrinkage stress applied to the bending region.

In the display device according to the exemplary embodiment of the present specification, the wiring disposed in the bending region may be formed in a plurality of layers, and the upper wiring is formed thickly to have a structure that mainly withstands tensile stress and contractile stress, and the lower wiring is relatively formed. By forming it thin, it can play an auxiliary role in firmly maintaining the structure of the upper wiring.

The display device according to the exemplary embodiment of the present specification may form a central groove by configuring the dome shape of the upper wiring disposed in the bending area in a double shape. By varying the size of the dome and the depth or width of the groove, it can withstand the tensile stress caused by the bending process well.

The display device according to the exemplary embodiment of the present specification may have a planar structure strong against tensile stress in the bending area by making the dome shape of the wiring disposed in the bending area to have a semicircular or trapezoidal plane.

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

Since the content of the invention described in the problems to be solved above, the means for solving the problems, and the effects do not specify the essential characteristics of the claims, the scope of the claims is not limited by the matters described in the content of the invention.

1 is a view showing a plan view of a display panel according to an embodiment of the present specification.
FIG. 2 is a cross-sectional view taken along the cutting line I-I' of FIG. 1 .
FIG. 3 is an enlarged cross-sectional view of a dotted line area II of FIG. 1 .
4 is an enlarged view of the bending area in which the cut portion of FIG. 2 is bent.
FIG. 5 is an enlarged view of a region adjacent to a cut surface of a substrate in a bending start region of FIG. 4 and is a plan view of wiring according to an embodiment of the present specification.
6A to 6C are cross-sectional views of wirings according to various embodiments of the present specification taken along line III-III′ of FIG. 5 .
7 is a cross-sectional view of a wiring according to another embodiment of the present specification taken along the cutting line III-III' of FIG.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of 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 the embodiments of the present invention are exemplary, and thus the present invention is not limited to the illustrated matters. Like reference numerals refer to like elements throughout. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. When 'including', 'having', 'consisting', 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 case in which the plural is included is included unless otherwise explicitly stated.

In interpreting the components, it is interpreted as including an error range even if there is no separate explicit description.

In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, one or more other parts may be positioned between the two parts unless 'directly' is used.

In the case of a description of a temporal relationship, for example, 'immediately' or 'directly' when a temporal relationship is described with 'after', 'following', 'after', 'before', etc. It may include cases that are not continuous unless this is used.

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

In describing the components of the present specification, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, order, or number of the elements are not limited by the terms. When it is described that a component is “connected”, “coupled” or “connected” to another component, the component may be directly connected or connected to the other component, but other components may be interposed between each component. It will be understood that each component may be “interposed” or “connected”, “coupled” or “connected” through another component.

As used herein, the term “display device” refers to a liquid crystal module (LCM) including a display panel and a driving unit for driving the display panel, an organic light emitting module (OLED Module), and a quantum dot module (Quantum Dot Module). It may include a display device. And, an electric field including a notebook computer, a television, a computer monitor, an automotive display or other type of vehicle, which is a complete product or final product including LCM, OLED module, QD module, etc. A set electronic device such as an equipment display, a mobile electronic device such as a smart phone or an electronic pad, or a set device or set apparatus may also be included.

Accordingly, the display device in the present specification may include a set device that is a narrow display device itself such as an LCM, an OLED module, a QD module, and an application product or an end-user device including an LCM, an OLED module, a QD module, etc. .

And, in some cases, the LCM, OLED module, and QD module composed of the display panel and the driver are expressed as a narrow “display device”, and the electronic device as a finished product including the LCM, OLED module, and QD module is “set” It can also be expressed as "device". For example, a display device in the narrow sense includes a liquid crystal (LCD), organic light emitting (OLED) or quantum dot display panel, and a source PCB that is a control unit for driving the display panel, and the set device is connected to the source PCB. It may be a concept further including a set PCB, which is a set controller that is electrically connected to control the entire set device.

The display panel used in this embodiment includes all types of liquid crystal display panels, organic light emitting diode (OLED) display panels, quantum dot (QD) display panels, electroluminescent display panels, etc. can be used, and is not limited to a specific display panel capable of bezel bending with the flexible substrate for the organic light emitting (OLED) display panel of the present embodiment and the lower backplay support structure. In addition, the display panel used in the display device according to the embodiment of the present specification is not limited to the shape or size of the display panel.

For example, when the display panel is an organic light emitting (OLED) display panel, it may include a plurality of gate lines and data lines, and pixels formed at intersections of the gate lines and the data lines. In addition, an array including a thin film transistor, which is a device for selectively applying a voltage to each pixel, an organic light emitting device (OLED) layer on the array, and an encapsulation substrate or an encapsulation layer disposed on the array to cover the organic light emitting device layer (Encapsulation) and the like may be configured. The encapsulation layer may protect the thin film transistor and the organic light emitting device layer from external impact, and may prevent penetration of moisture or oxygen into the organic light emitting device layer. In addition, the layer formed on the array may include an inorganic light emitting layer, for example, a nano-sized material layer or quantum dots.

1 herein illustrates an exemplary organic electroluminescent (OLED) display panel 100 that may be incorporated into displays.

1 is a view showing a plan view of a display panel according to an embodiment of the present specification. 1 is a diagram illustrating an exemplary organic electroluminescent display (OLED) panel 100 that may be disposed within displays.

Referring to FIG. 1 , an organic light emitting display panel 100 includes at least one active layer 101 in which light emitting devices and an array for driving the light emitting devices are formed.

The display panel 100 may include an inactive area IA disposed at a periphery of the active area AA, and upper, lower, left, and right sides of the active area AA may be referred to as an inactive area IA. The active area AA may have a rectangular shape, and various types of display devices such as a circle, an oval, or a polygon may be applied to a smart watch or a display device for a vehicle. Accordingly, the arrangement of the inactive area IA surrounding the active area AA is not limited to the organic light emitting (OLED) display panel 100 illustrated in FIG. 1 . Various components for driving the light emitting devices and arrays formed in the active area AA may be positioned in the left and right inactive areas IA of the active area AA to provide a function for stable light emission. For example, circuits such as GIP (Gate-in-Panel, 123) and ESD (Electrostatic Discharge, 124), a cathode that is a part of a light emitting device, and a low potential voltage (VSS) that is a voltage reference point of the light emitting device ) area for contact between the wiring 122, the encapsulation layer 170 for protecting the light emitting element from external moisture permeation or foreign matter to prevent overflowing to the outside of the display panel 100 during the application process of the foreign material compensation layer There may be multiple dam structures. In addition, a crack stopper structure for preventing cracks that may occur during the cutting process (scribing process) for dividing the mother substrate into individual display panels 100 from being transmitted to the inside of the display panel 100 (Crack stopper structure, 126), etc. may be disposed.

The crack prevention structure 126 of the present specification is a GIP 123 or ESD 124 or low potential voltage ( VSS) reaching the wiring 122 and destroying it or providing a vapor transmission path to the light emitting device or array formed in the active area AA to prevent dark spots from growing or pixel shrinkage from occurring .

The crack prevention structure 126 may be formed of an inorganic film or an organic film, and may be formed of a multilayer structure of an inorganic film and an organic film, but is not limited thereto. In FIG. 1 , the crack prevention structure 126 is illustrated as being disposed only on both sides of the long side and one side of the short side of the display panel 100 , but the present invention is not limited thereto. For example, the crack prevention structure 126 may also be disposed in the area where the bending area 103 and the notch 151 are formed, and may be disposed on the entire periphery of the substrate 110 .

In a region adjacent to the cut surface of the substrate 110 outside the crack preventing structure 126 , part or all of the insulating films (GI, buffer layer, etc.) deposited on the entire surface of the active region AA are etched by etching. can do. A small amount of the insulating film may be left on the upper portion of the substrate 110 through etching, or the upper surface of the substrate may be completely exposed to prevent the cutting impact from being transmitted to the insulating film.

Referring to FIG. 1 , an FPCB electrically connected to a pad 135 formed to receive an external power source and a data driving signal or to transmit and receive a touch signal may be disposed in a lower region of the display panel 100 . The wiring 121 for the high potential voltage VDD, the wiring 122 for the low potential voltage VSS, and/or the voltage wiring 127 for data extending from the FPCB may be disposed.

The data voltage line 127 of the present specification may be disposed to be connected to the data driver IC (IC) that generates the light emitting signal of the light emitting device 112 .

A region where the pad 135 and the data driver IC (IC) described above are disposed may be referred to as a second component forming part. A portion of the high-potential voltage wiring 121 and the low-potential voltage wiring 122 may be disposed in the second component forming portion.

Referring to FIG. 1 , in a display panel 100 according to an embodiment of the present invention, as indicated by a dotted line, a notch formed by cutting both lower corners of the display panel 100 for bending of the bending area BA. , 151) can be placed.

For example, when performing a cutting process for dividing the mother substrate into individual panels, the cut surface is cut inside the inactive area IA near the lower edge area of the display panel 100, which is a part of the inactive area IA. The notch 151 may be formed adjacent to the wiring 121 for the upper voltage VDD or the wiring 122 for the low potential voltage VSS.

As for the notch 151 of the present specification, the notch 151 starts at one end of the flexible substrate 110 and a bending process may be performed in the vicinity of the corresponding area. The bending process is terminated near the data driver IC 137 so that the flexible substrate area including the data driver IC and the FPCB pad 135 may be in contact with the back side of the flexible substrate 110 on which the active area AA is formed. .

The member connected to the pad 135 formed on the upper surface of the display panel 100 is not limited to the FPCB, and various members can be connected, and the position of the pad 135 may be disposed on the upper surface or the rear surface of the display panel 100 . Do.

Although the data driver IC (IC) is illustrated as being disposed on the upper surface of the display panel 100 in FIG. 1 , it is not limited to the data driver IC (IC). For example, the data driver IC (IC) may be disposed on the rear surface of the display panel 100 .

FIG. 2 is a cross-sectional view taken along the cutting line I-I' shown in FIG. 1 for emphasizing a cross-section in a state in which the inactive area IA of the display panel 100 of FIG. 1 is bent. In FIG. 2 , the active layer 101 is illustrated to include the flexible substrate 110 , a TFT that may be formed on the flexible substrate 110 , a light emitting device, and an encapsulation layer 170 .

The flexible substrate 110 may be, for example, a polyimide resin-based material, but is not limited thereto. A buffer layer 111 may be formed on the flexible substrate 110 and an active layer 101 may be formed. The buffer layer 111 may have a structure in which a plurality of inorganic insulating layers such as SiNx or SiOx are stacked, but is not limited thereto. The active layer 101 may be formed of low temperature polysilicon (LTPS), and a gate insulating layer 120 may be disposed on the active layer 101 . A gate layer GE may be formed on the gate insulating layer 120 , and the gate layer GE may be formed of molybdenum (Mo). An interlayer insulating layer 130 may be formed on the gate layer GE, and a hole is formed in the gate insulating layer 120 and the interlayer insulating layer 130 to activate the source electrode SE and the drain electrode DE of the TFT. It can be connected to the layer 101 . A first planarization layer 150 and a second planarization layer 160 may be disposed on the source electrode SE and the drain electrode DE. The planarization film may be formed of an organic film. An anode electrode AD, an organic light emitting material layer EL for light emission, and a cathode electrode CD may be formed on the second planarization layer 160 .

An encapsulation layer may be formed on the cathode electrode CD to protect the organic light emitting layer EL from external moisture or foreign matter. The encapsulation layer 170 may have a three-layer structure of an inorganic layer/organic layer/inorganic layer, and the inorganic layer may be Si-based SiNx, SiOx, or SiON. The structure of the encapsulation layer 170 is not limited thereto.

The organic layer applied to the encapsulation layer 170 may be a particle capping layer (PCL), but is not limited thereto. The particle cover layer may be formed of a material such as an epoxy resin that is a polymer. In the case of the inorganic film, an inorganic material composed of a plurality of layers such as SiNx/SiON rather than a single layer may be used.

The above-described buffer layer 111 to the encapsulation layer 170 may be referred to as the active layer 101 .

The bending region 103 is disposed in the inactive region IA that is the region surrounding the active layer 101 , and various types of bending regions 103 are disposed on the upper portion of the substrate 110 corresponding to the bending region 103 . A micro coating layer (MCL, 360) may be disposed to prevent cutting and breakage of the wires.

The micro-coating layer 360 is disposed on various wirings such as the data wiring 127, the high-potential voltage wiring 121, and the low-potential voltage wiring 122 formed on the bending region 103, so that when bending, The position can be adjusted to be closer to the Neutral Line. As a result, the tensile stress formed above the neutral line and the shrinkage stress formed below the neutral line are applied to the wirings as small as possible, thereby improving the durability of the wiring. In addition, the micro-coating layer 360 may also include a physical and chemical protection function capable of protecting various wires disposed on the flexible substrate 110 from external impact, moisture, or dust during the manufacturing process.

FIG. 3 is an enlarged view of an area in which the notch 151 of FIG. 1 is disposed, and shows components of the bending area BA and the inactive area IA before a bending process is performed.

The notch 151 may be generated by cutting the edge of the flexible substrate 110 at a position corresponding to the bending area BA folded toward the rear surface of the substrate 110 when bending in the inactive area IA. The substrate cutting line as shown in FIG. 3 may be formed by a substrate cutting method using a laser. For a slim bezel or a narrow bezel, the smaller the area of the substrate 110 bent during the bending process is, the smaller the stress applied to the substrate 110 during bending, so fairness can be further improved. In addition, in order to prevent the propagation of cracks that may occur during the cutting process, a crack preventing structure 126 may be formed inside the substrate 110 along the cut surface including the notch 151 . As shown in FIG. 3 , the cut surface of the substrate 110 may have rounded corners to improve fairness and durability.

The GIP 123 and the ESD 124 may be disposed on a side surface of the active area AA, and a low potential voltage line 122 for grounding may be disposed along the periphery. External power input from the pad 135 passes through the bending area BA through the high potential voltage line 121 , the data line 127 , and the gate power line 125 to the inactive area close to the active area AA ( ). IA) can be entered. Also, the data line 127 may extend from the driver IC (IC) to pass through the bending area BA and enter the active area AA. By configuring the various wirings to pass through the bending area BA, most of the wirings may be exposed to tensile stress and contractile stress during the bending process. When the bending area (BA) is bent with a radius of curvature (R: Radius curvature) smaller than the design value that the wires passing through the bending area (BA) can withstand, the stress is concentrated on the part corresponding to the radius of curvature smaller than the design value of the wiring This may cause damage to the wiring. Due to this, a defect in which the display panel 100 does not operate properly may occur.

4 is a cross-sectional view illustrating a stacked structure when bending of the display panel 100 is completed. For convenience of illustration, the TFT array and the light emitting device formed on the flexible substrate 110 in FIG. 4 are illustrated as the active layer 101 . The encapsulation layer 170 may be a triple layer of an inorganic layer/organic layer/inorganic layer covering the upper surface of the active layer 101 and the side surface of the bending area BA. The configuration of the encapsulation layer is not limited thereto.

A touch electrode layer 181 capable of recognizing a touch and a first adhesive layer may be disposed on the active layer 101 . The touch electrode layer 181 may be, for example, an electrostatic touch method capable of sensing a touch pressure, a force touch method, or a pen touch method in which a touch is performed using a pen, but is not limited thereto.

A polarization layer 182 may be disposed on the touch electrode layer 181 according to the embodiment of the present specification. The polarization layer 182 may minimize the effect that light generated from an external light source may have on the active layer 101 by entering the inside of the display panel 100 . The embodiment of the present specification is not limited to the structure of FIG. 4 . For example, when the touch sensitivity is sensitive, the order of the touch electrode layer 181 and the polarization layer 182 may be reversed.

According to the embodiment of the present specification, the second adhesive layer 183 may be disposed on the polarization layer 182 . The cover window 190 may be attached to the outside of the display panel 100 to protect the display panel 100 from an external environment. The cover window 190 may be a cover glass, a cover member, etc., but is not limited to terms.

A support layer 116 may be disposed under the flexible substrate 110 , and a second touch electrode layer may be disposed under the support layer 116 . The support layer 116 may be made of, for example, polyethylene terephthalate (PET), but is not limited thereto. The second touch electrode layer may be a second sensor layer for a force touch sensing touch pressure or an electromagnetic sensing type touch sensing layer for recognizing touch with a pen under the flexible substrate 110 .

A layer may be additionally disposed under the support layer 116 or under the second touch electrode layer. For example, the added layer may be a metal layer. Noise may be generated in the battery or semiconductor chips of the module to which the display panel 100 is attached, and electromagnetic interference (EMI) may occur in the display panel 100 due to the noise. can The electromagnetic interference may cause a malfunction in the thin film transistor of the active layer 101 or the organic light emitting device including the organic light emitting layer or abnormality of the display screen of the display panel. To prevent this, for example, by disposing a metal layer, electromagnetic interference (EMI) may be blocked. Alternatively, the metal layer may have a heat dissipation effect of dissipating heat generated from the display panel 100 and a rigid effect capable of more firmly supporting the flexible substrate 110 .

An adhesive layer 118 may be disposed between the bent flexible substrate 110 . The adhesive layer 118 may be disposed below the support layer 116 to maintain a bent shape. For example, the adhesive layer 118 may be a double-sided adhesive layer. For example, the double-sided adhesive layer may include a foam tape, a pressure sensitive adhesive, a foam-type adhesive, a liquid adhesive, a light curing adhesive, or other adhesive component. The adhesive layer 118 may be formed of or include a compressive material, which may be a cushion for portions bonded to the adhesive layer 118 . For example, the constituent material of the adhesive layer 118 may be a material having compressibility. The adhesive layer 118 may include a cushion layer interposed between an upper layer and a lower layer of an adhesive material, for example, a plurality of layers including polyolefin foam. The adhesive layer 118 may be disposed on at least one of an upper surface and a lower surface of the extended body portion of the support layer 116 .

The FPCB is formed on the upper surface of the flexible substrate 110 , but is bent to be electrically connected to the driver IC, the pad 135 and the pad 135 , and may be disposed on the opposite side of the active area AA.

A micro-coating layer 360 may be disposed to protect wiring on the flexible substrate 110 . For example, the micro-coating layer 360 is formed in the bending area BA so as to be in contact with the lower surface of the touch electrode layer 181 including the upper surface of the active layer 101 starting from the vicinity of the driver IC (IC) to protect the wiring. It can be configured as a whole. A portion of the micro-coating layer 360 may be over-applied at the end of application or may be disposed to contact or be adjacent to the side surface of the touch electrode layer 181 due to surface tension between the touch electrode layer 181 and the micro-coating layer 360 . The micro-coating layer 360 may be formed in the entire region from the adjacent region of the driver IC (IC) through the bending region BA to the active layer 101, and as described in FIG. 1 , the inactive region IA and It may be disposed along a line of the notch 151 formed across the bending area BA.

FIG. 5 is a plan view of the bending start portion of FIG. 4 .

5 shows that at the beginning of bending, various wires such as a high potential voltage (VDD) wire, a low potential voltage (VSS) wire, and a data signal line extending from the active area AA are formed in the inactive area IA and the bending area BA. Shows a plane disposed in the first direction in the middle portion of the.

On the left side of FIG. 5 , there may be a notch 151 in a trimming line through which the flexible substrate 110 is cut. A crack prevention structure 126 may be disposed to prevent cracks that may occur during the laser cutting process for forming the notch 151 from being transmitted to the wiring forming section. The flexible substrate 110 may be formed of a flexible material such as polyimide. The polyimide material has liquid-like flexibility before curing, but when cured, the surface hardness increases and heat resistance is relatively excellent. Accordingly, while having a function of forming an insulating film and wiring on the upper surface of the film, it can be flexibly deformed, so that it can be used in a flexible device. However, when the laser cutting process is performed to cut from the mother substrate to an individual device, there may be disadvantages in that cracks are generated at the cut surface or moisture easily penetrates into the roughened side surface. To this end, it is possible to protect the elements disposed inside the flexible substrate 110 by forming a buffer structure in consideration of cracks or penetration of foreign substances or moisture with a plurality of inorganic or organic films near the laser cutting surface. The cushioning structure may be referred to as a crack preventing structure 126, and the term is not limited thereto. Since the crack preventing structure 126 is disposed in the bending area BA, like elements in the active area AA, it is necessary to protect various wirings in the bending area BA from cracks or penetration of moisture.

Among the wirings extending from the active area AA, a wiring extending further to the bending area BA may be configured as the bending wiring 300 . The bending wiring 300 may extend from the inactive area IA through the bending area BA to the drive IC (IC) or the pad 135 , and bending is performed in the direction in which the bending wiring 300 extends. . Accordingly, tensile stress may be applied parallel to the direction in which the bending wiring 300 extends. The bending wiring 300 capable of withstanding such tensile stress may be arranged in consideration of the arrangement of the line width and the height of the wiring. The line width of the bending wiring 300 has a line width that does not generate cracks, and the resistance of the bending wiring 300 must be low because electrical signal transmission, which is the role of the bending wiring 300 , must be easy. Accordingly, in terms of resistance, the larger the line width of the bending wiring 300 is, the better, but in terms of crack generation, the smaller the line width, the more smoothly bending and stress can be tolerated.

When configuring the bending wiring 300 , the thickness of the wiring may be considered. Similarly to the line width, in terms of resistance, if the thickness of the bending wiring 300 is thick, low resistance may be achieved, but the possibility of cracking may increase. If the thickness is thin, it can withstand more smooth bending and stress, but the electrical resistance increases and the performance of the wiring may deteriorate. Accordingly, the wiring disposed in the bending area BA must be applied to overcome the tensile stress applied to the bending area BA within considerations such as line width and thickness.

Referring to FIG. 5 , a groove portion 410 may be disposed on the bending wire 300 in parallel to the extending direction of the bending wire 300 . Since the groove portion 410 allows the bending wiring 300 to have a partially different thickness, the possibility of occurrence of cracks due to the thickness of the wiring may be reduced. The groove portion 410 may be disposed in the central portion of the bending wire 300 and extend parallel to the direction of the bending wire 300 . The groove portion 410 disposed on the bending wire 300 may vary depending on the shape of the bending wire 300 . For example, if the shape of the bending wiring 300 is a line shape as shown in FIG. 5 , the groove portion 410 may also be disposed in a line shape. When the bending wiring 300 has a circular or zigzag shape, the shape of the groove 410 may also have a circular or zigzag shape.

6A to 6C are views illustrating a cross-section according to an embodiment of the present specification taken along line III-III′ of FIG. 5 .

Referring to FIG. 6A , a cross-section of the bending wiring 300 is shown. For example, the flexible substrate 110 may have a bending wire 300 disposed thereon, and one bending wire 300 may have two trapezoidal protrusions 310 . In order to form the two trapezoidal protrusions 310 , a groove 410 may be formed in the center of the bending wiring 300 . The groove portion 410 may not remove all of the bottom surface or the lower surface of the bending wiring 300 , but may leave some wiring so that the two trapezoidal protrusions 310 can be connected. When the groove portion 410 is formed to expose the flexible substrate 110 , for example, the etching of the bending wiring 300 proceeds to the base surface or the lower surface so that the protrusions 310 formed on both sides of the groove portion 410 are completely removed. Separation can increase the electrical resistance of the wiring. Accordingly, the groove portion 410 may be disposed at a predetermined distance from the base surface or the lower surface of the bending wiring 300 . By forming the groove portion 410 , the overall thickness of the bending wiring 300 may be increased, and tensile stress applied during bending may be better tolerated. For example, stress generated during bending by the groove portion 410 may be distributed to a wide surface of the bending wiring 300 . Tensile stress applied per unit area may be reduced due to an increase in the surface area of the bending wiring 300 .

The groove portion 410 may use a halftone method in a photolithography for forming the bending wiring 300 . Although the shape of the protrusion 310 is exemplified as a trapezoid, it is not limited thereto.

For example, referring to FIGS. 6B to 6C , the protrusion 310 may be implemented in a semicircular dome shape or a triangular pyramid shape. Similar to the protrusion 310 described in FIG. 6A , a semicircular dome shape or a triangular pyramid The protrusion 310 in the shape of a halftone method during a photo process for making a pattern of the bending wiring 300 and an etch rate (Etch) process for removing a photo resist (PR: Photo resist) used in the photo process rate) can be adjusted. The trapezoidal protrusion 310 may pattern the bending wiring 300 in a halftone method only for the temporary groove 410 .

The semicircular dome structure or the triangular pyramid-shaped protrusion 310 may be configured in the form of a gentle curve or a triangular side by applying halftones to the center and left and right ends of the bending wiring 300 . Since the trapezoidal protrusion 310 can form a predetermined bending wiring 300 finely in the bending area BA, it may be advantageous in process. In this case, since the upper surface of the bending wire 300 has a constant width, the cross-sectional area of the bending wire 300 may be wide and resistance may be low. However, since an inclination is formed at two points on the upper surface of the bending wiring 300 , tensile stress may be concentrated at the angled inflection point. In order to remove the inflection point, the protrusion 310 having a semicircular dome structure may be configured.

Since the protrusion 310 of the semicircular dome structure of FIG. 6B may be configured to have no inflection point, it is possible to reduce or minimize a phenomenon in which the tensile stress is concentrated at a specific point. However, the protrusion 310 of the semicircular dome structure may be configured by simultaneously adjusting the halftone and the etch rate. If the trapezoidal protrusion has a large cross-sectional area of the bending wire 300 and cracks are increased, the bending wire 300 may be formed with the triangular pyramidal protrusion 310 to reduce cracking.

The triangular pyramidal protrusion 310 of FIG. 6C may be configured to form a wider area to be etched during the photo process, so that the upper surface of the bending wiring 300 is formed as a single point. In the triangular pyramidal protrusion 310 , the cross-sectional area of the bending wire 310 is relatively reduced, so that the electrical resistance of the wire may increase. However, since the cross-sectional area is reduced, it is possible to more effectively respond to tensile stress applied during bending.

A first planarization layer 150 may be disposed on the bending wiring 300 .

Considering the line width of the wiring, when the bending wiring 300 has a line width of about 6 to 10 μm, it may be advantageous in the bending process, but is not limited thereto, and may have various line widths. Also, when the bending wiring 300 has a thickness of about 4000 to 6000 Å, it may be advantageous for a bending process. The thickness of the bending wiring 300 is not limited thereto, and may have various thicknesses. In the case of the central groove portion 410 , it may be formed so as to remain at a height of about 500 to 1000 Å from the base or lower surface of the bending wiring 300 . The bending wiring 300 may be formed of molybdenum (Mo) or aluminum (Al), but is not limited thereto. If aluminum is used as the bending wiring 300, since aluminum oxide is formed by reacting with oxygen in the atmosphere after deposition, the wiring may be torn or oxidized. To prevent this, oxidation of aluminum may be prevented by further depositing titanium (Ti; Titanium) on the aluminum wiring.

7 is a view showing a cross-section of the embodiment taken along line III-III' of FIG. 5 .

The bending wiring 300 of FIG. 7 may have a trapezoidal protrusion 310 similar to that of FIG. 6A . The bending wiring 300 of FIG. 6A uses a single-layered metal, but in FIG. 7, a multi-layered or double-layered metal may be used to form a wiring stronger against bending cracks. Although the trapezoidal protrusion 310 of FIG. 6A is illustrated as an example of the bending wiring 300 using a multilayer or double metal in FIG. 7 , the semi-circular dome protrusion 310 or the triangular cone shape protrusion 310 used in FIGS. 6B to 6C . ) can also be applied.

The bending wiring 300 having a multilayer structure may include a lower bending wiring 320 and a protrusion 310 . 7 , the protrusion may be referred to as an upper bending wiring. In FIG. 7 , the protrusion will be described as an upper bending wiring.

A lower bending wiring 320 and an upper bending wiring 310 may be formed on the flexible substrate 110 and patterned by a photo process. In this case, a halftone method may be used to form the groove portion 410 in the center of the upper bending wiring 310 . For example, the upper bending wirings 310 may be etched to be spaced apart from each other to expose the lower bending wirings 320 . When the upper bending wirings 310 are spaced apart from each other by etching to expose the lower bending wirings 320 , the cross-sectional area of the upper bending wirings 310 is reduced, thereby reducing the occurrence of cracks when the bending area BA is bent. In addition, durability against cracks may be further increased by using a crack-resistant metal for the lower bending wiring 320 . For example, the lower bending wiring 320 may be made of titanium (Ti), and the upper bending wiring 310 may be formed of molybdenum (Mo) or aluminum (Al). When aluminum is configured as the bending wiring 300, the wiring may be torn or oxidized by reacting with oxygen in the atmosphere after deposition. To prevent this, it is possible to prevent oxidation of aluminum by further depositing titanium (Ti; titanium) on the aluminum wiring.

A display device according to an embodiment of the present specification includes a liquid crystal display device (LCD), a field emission display device (FED), an organic light emitting display device (OLED), and a Quantum Dot Display Device.

A display device according to an embodiment of the present specification is a laptop computer, a television, a computer monitor, an automotive display apparatus, or another vehicle (vehicle), which is a complete product or final product including an LCM, an OLED module, and the like. A set electronic device or set apparatus such as an electronic device including a form and the like, a mobile electronic device such as a smartphone or an electronic pad, or the like may also be included. can

A display device according to an embodiment of the present specification may be described as follows.

A display device according to an exemplary embodiment of the present specification includes an active area and an inactive area, and the inactive area includes a first area adjacent to the active area, a second area on which a pad is disposed, and between the first area and the second area. There is a substrate including a bending region, and a wiring extending from a first region to a second region, and the wiring may include a protrusion and a groove in the bending region.

In the display device according to the exemplary embodiment of the present specification, the protrusion may have a trapezoidal shape.

In the display device according to the exemplary embodiment of the present specification, the protrusion may have a semicircular dome shape.

In the display device according to the embodiment of the present specification, the protrusion may have a triangular shape.

In the display device according to the exemplary embodiment of the present specification, the groove portion may be disposed in a central portion of the wiring.

In the display device according to the exemplary embodiment of the present specification, the groove may be formed without exposing the upper surface of the substrate.

The display device according to the exemplary embodiment of the present specification may further include a lower bending wire disposed on a lower surface of the protrusion.

In the display device according to the exemplary embodiment of the present specification, the lower bending wiring and the line-shaped protrusion may be formed of different materials.

The display device according to the exemplary embodiment of the present specification may further include a first planarization layer that fills the curved electrode of the groove and is disposed on the wiring.

In the display device according to the exemplary embodiment of the present specification, the protrusion and the groove may include a line shape.

The display device according to the embodiment of the present specification may further include a micro-coating layer on the first planarization layer so that the wiring comes to a neutral plane in the cross-sectional structure of the bending region.

A display device according to an exemplary embodiment of the present specification includes a substrate including a display area and a non-display area, a light emitting display device disposed in the display area, and an encapsulation disposed on the light emitting display device and disposed on at least a portion of the non-display area The polarizing layer disposed on the layer and the encapsulation layer, the cover window, and the non-display area include a bending area, the bending area includes a bending wire extending to the light emitting display device, and the bending wire has a bending wire parallel to the extending direction It includes a line-shaped groove that is disposed to be in the same manner, and the line-shaped groove may be disposed to be spaced apart from the substrate.

In the display device according to the exemplary embodiment of the present specification, the bending wiring may further include a protrusion formed by the line-shaped groove.

In the display device according to the embodiment of the present specification, the protrusion has a trapezoidal cross-section.

In the display device according to the exemplary embodiment of the present specification, the protrusion may have a semicircular dome-shaped cross-section.

In the display device according to the embodiment of the present specification, the bending wiring may further include a second electrode layer in which the protrusion serves as the first electrode layer and is disposed on the lower surface of the protrusion.

Features, structures, effects, etc. described in the above-described examples of the present application are included in at least one example of the present application, and are not necessarily limited to only one example. Furthermore, features, structures, effects, etc. illustrated in at least one example of the present application may be combined or modified with respect to other examples by those of ordinary skill in the art to which the present application belongs. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present application.

The present application described above is not limited to the above-described embodiments and the accompanying drawings, and it is common in the technical field to which this application pertains that various substitutions, modifications, and changes are possible without departing from the technical matters of the present application. It will be clear to those who have the knowledge of Therefore, the scope of the present application is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present application.

100: display panel
AA: active area IA: inactive area
BA: bending area
110: substrate 111: multi-buffer layer
120: gate insulating layer 130: first interlayer insulating film
140: second interlayer insulating film
150: first planarization film 160: second planarization film
170: encapsulation layer
121: high potential voltage wiring (Vdd) 122: low potential voltage wiring (Vss)
123: GIP 124: ESD
125: gate power line
126: Crack Stopper Structure
127: data wiring
116: support layer 118: double-sided adhesive layer
181: first adhesive layer and touch film 182: polarizing film
183: second adhesive layer
190: cover glass
360: micro coating layer (MCL: Micro Coating layer)
134: foam tape (Foam Tape)
135: pad
IC: Driver IC
151: cut plane
300: bending wiring 310: protrusion, upper bending wiring
320: lower bending wiring 410: groove

Claims (16)

A substrate comprising an active region and an inactive region, wherein the inactive region includes a first region adjacent to the active region, a second region on which a pad is disposed, and a bending region between the first region and the second region ;
a wiring extending from the first area to the second area; and
The wiring includes a protrusion and a groove in the bending region.
According to claim 1,
The protrusion has a trapezoidal shape.
According to claim 1,
wherein the protrusion has a semicircular dome shape.
According to claim 1,
The protrusion has a triangular shape.
According to claim 1,
The groove portion is disposed in a central portion of the wiring.
6. The method of claim 5,
The groove portion does not expose a top surface of the substrate.
According to claim 1,
The wiring further includes a lower bending wiring disposed on a lower surface of the protrusion.
8. The method of claim 7,
and the lower bending wiring and the protrusion are formed of different materials.
7. The method of claim 6,
and a first planarization layer disposed on the wiring and filling the line-shaped groove portion.
10. The method of claim 9,
and a micro-coating layer on the first planarization layer so that the wiring is on a neutral plane in a cross-section of the bending region.
According to claim 1,
and the protrusion and the groove have a line shape.
a substrate including a display area and a non-display area;
a light emitting display device disposed in the display area and an encapsulation layer disposed on the light emitting display device and disposed on at least a portion of the non-display area; and
and a polarizing layer and a cover window disposed on the encapsulation layer,
the non-display area includes a bending area;
the bending region includes a bending wiring extending to the light emitting display device;
the bending wiring includes a line-shaped groove disposed parallel to a direction in which the bending wiring extends;
The line-shaped groove portion is disposed to be spaced apart from the substrate.
13. The method of claim 12,
The bending wiring further includes a protrusion formed as the line-shaped groove.
14. The method of claim 13,
The protrusion has a trapezoidal shape.
14. The method of claim 13,
wherein the protrusion has a semicircular dome shape.
14. The method of claim 13,
The protrusion is a first electrode layer,
The flexible display device further comprising a second electrode layer disposed on a lower surface of the protrusion.

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