KR20230094571A - Display apparatus - Google Patents

Abstract

A display device according to an embodiment of the present specification includes: a substrate including a display area, a non-display area adjacent to the display area, and a bending area provided in at least a portion of the non-display area; a first connection wire disposed on the substrate in the bending area; It may include a first planarization layer disposed on the first connection wire, and a second connection wire disposed on the first planarization layer.

Description

Display device {DISPLAY APPARATUS}

The present specification relates to a display device, and more particularly, to a display device including a rigidity-enhanced wiring structure in a bending region of a flexible substrate.

Recently, as we enter the information age, the display field that visually expresses electrical information signals has developed rapidly. is being developed.

Specific examples of such a display device include a liquid crystal display device (LCD), an organic light emitting display device (OLED), and a quantum dot display device (Quantum Dot Display Apparatus).

The display device includes driving circuits to drive pixels. Examples of drive circuits include gate drivers, emission (source) drivers, power (VDD) routing, electrostatic discharge (ESD) circuits, multiplex (MUX) circuits, data signal lines, cathode contacts, and other functional elements. include A plurality of peripheral circuits may be included to provide various kinds of additional functions, for example, touch sensing or fingerprint identification functions. The driving circuit may be disposed in a non-active area adjacent to a display area where an image is displayed.

As display devices are used in various ways, designs of display devices are becoming diversified in order to reduce the area of a non-display area where images are not displayed for aesthetics of users. A high ratio of the size of the display area to the size of the non-display area is one of the most important design issues.

In order to solve the above problems, research is being conducted to bend or bend various parts of the display device by applying a flexible material to the substrate of the display device and using the flexible property of the flexible substrate.

Therefore, by bending the flexible substrate and folding all or part of the non-display area and placing it on the rear surface of the display area, the non-display area is hidden from users, thereby providing a display device in which the ratio of the display area visible to users is increased. there is.

While manufacturing a display device using a flexible substrate, it has become an important task to secure flexibility of various insulating layers formed on the substrate and wires formed of metal materials.

Mechanical stress applied to a bent region (bending region) of a flexible substrate causes cracks or disconnection in wires formed in the bent region. Cracks and disconnections in wiring may interfere with image driving in the display area, causing abnormal image display problems.

Therefore, various studies have been made to prevent cracks and disconnections of wires in a bending area where a flexible substrate of a display device is bent, but it is still insufficient, and development thereof is urgently required.

The problem to be solved by the present specification is to distribute the tensile force applied to the bending area formed during or after the bending process of the substrate to remove cracks and disconnection of wiring caused by mechanical stress in the bending area. A display device including a double wiring structure of a connection wire and a second connection wire is provided.

Another problem to be solved by the present specification is to provide first connection wires arranged in a pattern to remove cracks and disconnections of wires by dispersing tensile force acting on a bent substrate or during a bending process.

Another problem to be solved by the present specification is to provide a display device in which an angle of an inclined plane formed by a hole in a first flattening layer is set to prevent a problem in which a first connection wire and a second connection wire are not connected or disconnected. will be.

Another problem to be solved by the present specification is to provide a display device having improved reliability by normally transmitting signals by removing cracks and disconnections of connection wires.

Another problem to be solved by the present specification is to arrange a non-display area that does not display an image on the rear surface of the display device so that it is not exposed to the user's field of view, thereby increasing the size of the display area of the display device recognized by users and providing high aesthetics. It provides a sense.

A display device according to an embodiment of the present specification includes: a substrate including a display area, a non-display area adjacent to the display area, and a bending area provided in at least a portion of the non-display area; a first connection wire disposed on the substrate in the bending area; a first planarization layer disposed on the first connection wire; and a second connection wire disposed on the first planarization layer.

A display device according to another exemplary embodiment of the present specification includes a substrate including a display area, a non-display area adjacent to the display area, and a bending area in at least a portion of the non-display area, a thin film transistor disposed in the display area, and a bending area. a first planarization layer disposed on the disposed first connection wire, the thin film transistor in the display area, and the first connection wire in the bending area; and a connection electrode disposed in the display area on the first planarization layer and a second connection wire disposed in the bending area.

The problems to be solved according to the embodiments of the present specification are not limited to the above-mentioned problems, and other problems not mentioned above will be clearly understood by those skilled in the art from the description below.

In the display device according to the exemplary embodiment of the present specification, since the connection wiring unit has a double wiring structure of a first connection wiring and a second connection wiring, bending is performed by dispersing tensile force applied to a bending area formed during or after a bending process of a substrate. It is possible to remove cracks and disconnection of wires caused by mechanical stress in the area.

In the display device according to the exemplary embodiment of the present specification, by arranging the first connection wires in a pattern shape, cracks and disconnections of the wires may be removed by dispersing tensile force acting on the bent substrate during a bending process.

In the display device according to the exemplary embodiment of the present specification, it is possible to prevent a problem in which the first connection wire and the second connection wire are not connected or disconnected by setting the angle of the inclined surface formed by the hole of the first planarization layer.

The display device according to the exemplary embodiment of the present specification can improve reliability by normally transferring an image signal sent from a driving circuit to a display area by eliminating cracks and disconnection of connection wires.

In the display device according to the exemplary embodiment of the present specification, since a non-display area that does not display an image is disposed on the rear surface of the display device so that it is not exposed to the user's field of view, the size of the display area is increased to provide a high sense of aesthetics.

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 description below.

1 is a display device according to an embodiment of the present specification.
2 is a plan view of a display device according to an exemplary embodiment of the present specification.
3 is a cross-sectional view of a display device according to an exemplary embodiment of the present specification.
FIG. 4 is an enlarged plan view of a part of the bending area of FIG. 3 .
FIG. 5 is an enlarged cross-sectional view of a portion of the bending area of FIG. 3 .

Advantages and features of this specification, and methods of achieving them, will become clear with reference to embodiments described below in detail in conjunction with the accompanying drawings. However, this specification is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only these embodiments make the disclosure of this specification complete, and common knowledge in the art to which this specification belongs. It is provided to completely inform the person who has the scope of the invention, and this specification is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of this specification are illustrative, so this specification is not limited to the matters shown. Like reference numbers designate like elements throughout the specification. In addition, in describing the present specification, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present specification, the detailed description will be omitted. When "includes", "has", "consists of", etc. mentioned in this specification is used, other parts may be added unless "only" is used. In the case where a component is expressed in the singular, the case including the plural is included unless otherwise explicitly stated.

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

In the case of a description of a positional relationship, for example, when the positional relationship of two parts is described as "on", "upper", "at the bottom", "next to", etc., for example, "right" Or, unless "directly" is used, one or more other parts may be located between the two parts.

In the case of a description of a temporal relationship, if a temporal precedence relationship is described with "after", "following", "next to", "before", etc., unless "immediately" or "direct" is used, it is not continuous. cases may be included.

Although 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. Therefore, the first component mentioned below may be the second component within the technical spirit of the present specification.

In describing the components of the present specification, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, order, or number of the corresponding component is not limited by the term. When an element is described as being "connected", "coupled", or "connected" to another element, that element is directly connected or capable of being connected to the other element, but unless specifically stated otherwise. It should be understood that other components may be "interposed" between each component that is indirectly connected or capable of being connected.

“At least one” should be understood to include all combinations of one or more of the associated elements. For example, "at least one of the first, second, and third elements" means not only the first, second, or third elements, but also two of the first, second, and third elements. It can be said to include a combination of all components of one or more.

In this specification, “device” may include a display device such as a liquid crystal module (LCM) including a display panel and a driving unit for driving the display panel, and an organic light emitting display module (OLED module). In addition, electric devices including laptop computers, televisions, computer monitors, automotive apparatuses, or other types of vehicles, which are complete or final products including LCM and OLED modules, etc. It may also include a set electronic apparatus such as an equipment apparatus, a mobile electronic apparatus such as a smart phone or an electronic pad, or a set device or set apparatus.

Accordingly, the device in the present specification may include a display device itself such as an LCM, an OLED module, and the like, and an application product including the LCM, an OLED module, and the like, or a set device that is a device for end consumers.

And, in some embodiments, an LCM and OLED module composed of a display panel and a driving unit may be expressed as a “display device”, and an electronic device as a finished product including the LCM and OLED module may be distinguished and expressed as a “set device”. . For example, the display device may include a liquid crystal (LCD) or organic light emitting (OLED) display panel and a source PCB that is a controller for driving the display panel. The set device may further include a set PCB that is a set controller that is electrically connected to the source PCB and drives the entire set device.

All types of display panels such as liquid crystal display panels, organic light emitting diode (OLED) display panels, and electroluminescent display panels may be used as the display panels used in the embodiments of the present specification. Examples are not limited thereto. For example, the display panel may generate sound by being vibrated by the vibration device according to the embodiment of the present specification. A display panel applied to a display device according to an exemplary embodiment of the present specification is not limited to a shape or size of the display panel.

Each feature of the various embodiments of the present specification can be partially or entirely combined or combined with each other, technically various interlocking and driving are possible, and each embodiment can be implemented independently of each other or can be implemented together in an association relationship. may be

Hereinafter, looking at the embodiments of the present specification through the accompanying drawings and embodiments are as follows. Since the scales of the components shown in the drawings have different scales from actual ones for convenience of explanation, they are not limited to the scales shown in the drawings.

Hereinafter, various embodiments of the present specification will be described in detail with reference to the accompanying drawings.

1 is a display device according to an embodiment of the present specification. 2 is a plan view of a display device according to an exemplary embodiment of the present specification.

Referring to FIGS. 1 and 2 , the display device 100 according to the exemplary embodiment of the present specification includes a display area AA, a non-display area NA, and a bending area BA.

The display device 100 may include various additional elements for generating various signals or driving a plurality of sub-pixels SP in the display area AA. Additional elements for driving the sub-pixel SP may include an inverter circuit, a multiplexer, an electro static discharge (ESD) circuit, and the like. The display device 100 may also include additional elements related to functions other than driving the sub-pixel SP. For example, the display device 100 may include additional elements providing a touch sensing function, a user authentication function (eg, fingerprint recognition), a multi-level pressure sensing function, and a tactile feedback function. The aforementioned additional elements may be located in the non-display area NA or an external circuit connected to the connection interface.

Referring to FIGS. 1 and 2 , the substrate 110 may include an active area (AA) and a non-active area (NA) surrounding the display area AA. The non-display area NA of the substrate 110 may be adjacent to the display area AA and disposed outside the display area AA.

The display area AA is an area in which a plurality of sub-pixels SP are disposed to display an image. Each of the plurality of sub-pixels SP is an individual unit that emits light, and each sub-pixel SP may emit, for example, red, green, blue, or white light. no.

The display area AA may include an organic light emitting diode. A thin film transistor and a light emitting element layer may be disposed in each of the plurality of sub-pixels SP. For example, a display element for displaying an image and a circuit unit for driving the display element may be disposed in the plurality of sub-pixels SP.

The non-display area NA is an area in which an image is not displayed, and is an area where various wires and driving circuits for driving the plurality of sub-pixels SP disposed in the display area AA are disposed. For example, various ICs and driving circuits such as a gate driver IC and a data driver IC may be disposed in the non-display area NA. The non-display area NA may be a bezel area and is not limited thereto.

As shown in FIGS. 1 and 2 , the non-display area NA may be disposed around the display area AA. For example, the non-display area NA may be an area surrounding the display area AA. The non-display area NA may be an area extending from the display area AA. Alternatively, the non-display area NA may be an area in which the plurality of sub-pixels SP are not disposed, but is not limited thereto.

1 and 2 show that the non-display area NA surrounds the rectangular display area AA, the shape of the display area AA and the non-display area NA adjacent to the display area AA The form and arrangement are not limited to the examples shown in FIGS. 1 and 2 . The display area AA and the non-display area NA may have shapes suitable for the design of an electronic device in which the display device 100 is mounted. In the case of a display device of a wearable device by a user, it may have a circular shape like a general wrist watch, and the concepts of the embodiments of the present specification can be applied to a free-form display device applicable to a vehicle dashboard. may be applied. Exemplary shapes of the display area AA may be pentagonal, hexagonal, circular, elliptical, etc., but are not limited thereto.

The non-display area NA is an area in which various signal lines such as scan lines and circuit parts such as the connection wiring unit 300 and the gate driver 112 are formed. The gate driver 112 may be disposed in a gate-in-panel (GIP) shape. Also, a data driver may be disposed in the non-display area NA.

A bending area (BA) may be provided in a portion of the non-display area NA. The bending area BA may be provided between the pad part 114 located in the display area AA and the non-display area NA. Also, the bending area BA may be an area where the connection wiring unit 300 is formed.

The bending area BA is a region in which a portion of the substrate 110 is bent (bent) to dispose the pad portion 114 and an external module bonded to the pad portion 114 on the rear side of the substrate 110 . For example, as the bending area BA is bent toward the rear surface of the substrate 110, the external module bonded to the pad portion 114 of the substrate 110 moves toward the rear surface of the substrate 110. ) External modules may not be recognized when viewed from the top. In addition, as the bending area BA is bent, the size of the non-display area NA visible from above the substrate 110 is reduced, so that a narrow bezel may be realized. In this specification, it is illustrated that the bending area BA is present in the non-display area NA, but is not limited thereto. For example, the bending area BA may be located in the display area AA, and since the display area AA itself can be bent in various directions, the bending area BA located in the display area AA is also described herein. can have the mentioned effect.

A pad unit 114 is disposed on one side of the non-display area NA. The pad part 114 is a metal pattern to which external modules, for example, a flexible printed circuit board (FPCB) and a chip on film (COF) are bonded. Although the pad part 114 is illustrated as being disposed on one side of the substrate 110, the shape and arrangement of the pad part 114 are not limited thereto.

The connection wiring unit 300 may be disposed in the non-display area NA. For example, it may be disposed in the bending area BA where the substrate is bent among the non-display area NA. The connection wiring unit 300 may be configured to transfer a signal (voltage) from an external module bonded to the pad unit 114 to a circuit unit such as the display area AA or the gate driver 112 . For example, various signals such as various signals for driving the gate driver 112 , data signals, high potential voltages, and low potential voltages may be transmitted through the connection wiring unit 300 . According to the present specification, the connection wiring unit 300 may include the same material as various conductive components constituting the thin film transistor and the light emitting element layer disposed in the display area AA, and may be formed at the same time by the same process. can

The driver is disposed in the non-display area NA of the substrate 110 and provides a driving signal to the thin film transistor of the sub-pixel SP. For example, the driver may be the gate driver 112 providing a gate signal to the thin film transistor. The gate driver 112 includes various gate driving circuits, and the gate driving circuits may be directly formed on the substrate 110 . In this case, the gate driver 112 may be a gate-in-panel (GIP).

3 is a plan view of a display device according to an exemplary embodiment of the present specification. FIG. 2 is a cross-sectional view taken along line II′ shown in FIG. 1 .

Referring to FIG. 3 , the display device 100 according to the exemplary embodiment of the present specification includes a substrate 110, a first connection wire 310, a second connection wire 320, and a first planarization layer 130. do.

The substrate 110 may support various components of the display device. The substrate 110 may be made of a plastic material having flexibility (or flexibility).

For example, the substrate 110 may be made of polyimide (PI). When the substrate 110 is made of polyimide, the manufacturing process of the light emitting display device proceeds with a support substrate made of glass disposed below the substrate 110, and the manufacturing process of the display device is completed and then supported. The substrate may be released. Also, after the support substrate is released, a back plate (or plate) for supporting the substrate 110 may be disposed under the substrate 110 .

When the substrate 110 is made of polyimide, moisture penetrates the substrate 110 made of polyimide, and the moisture permeates to the thin film transistor or light emitting element layer, which can deteriorate the performance of the display device. there is. The display device according to the exemplary embodiment of the present specification may be composed of two pieces of polyimide to prevent deterioration in performance of the display device due to moisture permeation. In addition, by forming an inorganic film between the two polyimides, it is possible to improve the performance reliability of the product by blocking the permeation of moisture components into the lower polyimide. The inorganic layer may be formed of a single layer of silicon nitride (SiNx) or silicon oxide (SiOx) or multiple layers thereof, but is not limited thereto.

The substrate 110 is also referred to as a concept including a device and a functional layer formed on the substrate 110, for example, a switching device, a thin film transistor connected to the switching device, an organic light emitting device connected to the thin film transistor, and a protective layer. do.

The buffer layer 111 may be disposed on the entire surface of the substrate 110 . The buffer layer 111 can improve adhesion between the layers formed on the buffer layer and the substrate 110 and block various types of defect-causing factors such as alkali components flowing out from the substrate 110 . In addition, the buffer layer 111 may delay diffusion of moisture or oxygen penetrating into the substrate 110 .

The buffer layer 111 may be formed of a single layer or multiple layers of silicon nitride (SiNx) or silicon oxide (SiOx), but is not limited thereto. When the buffer layer 111 is formed of multiple layers, silicon oxide (SiOx) and silicon nitride (SiNx) may be alternately formed.

The buffer layer 111 may be omitted based on the type and material of the substrate 110, the structure and type of the thin film transistor, and the like.

Hereinafter, components formed in each area according to the display area AA, the non-display area NA, and the bending area BA will be described.

The thin film transistor 120 , the first planarization layer 130 , the connection electrode 140 , and the second planarization layer 150 may be disposed in the display area AA.

A thin film transistor 120 may be disposed in the display area AA on the buffer layer 111 .

The thin film transistor 120 includes a semiconductor layer 121, a gate electrode 123, a source electrode 125S, and a drain electrode 125D. The thin film transistor 120 is a driving thin film transistor and has a top gate structure in which a gate electrode 123 is disposed on the semiconductor layer 121 . For convenience of explanation, only a driving thin film transistor among various thin film transistors that may be included in the display device 100 is illustrated, but other thin film transistors such as switching thin film transistors may also be included in the display device 100 . Also, for convenience of description, the thin film transistor 120 has been described as having a coplanar structure, but may be implemented in other structures such as a staggered structure.

A semiconductor layer 121 may be disposed on the buffer layer 111 in the display area AA. The semiconductor layer 121 may be made of polycrystalline silicon. Polysilicon is formed by depositing an amorphous silicon (a-Si) material on the buffer layer 111, performing a dehydrogenation process, a crystallization process, an activation process, and a hydrogenation process, and patterning the polysilicon to form a semiconductor layer ( 121) can be formed. When the semiconductor layer 121 is made of polysilicon, the thin film transistor 120 may be an LTPS thin film transistor using low temperature poly-silicon (LTPS). The polysilicon material has high mobility, and when the semiconductor layer 121 is made of polysilicon, there are advantages in that energy consumption is low and reliability is excellent.

In addition, the semiconductor layer 121 may be made of amorphous silicon (a-Si) or may be made of various organic semiconductor materials such as pentacene. For another example, the semiconductor layer 121 may be made of oxide.

A first insulating layer 122 may be disposed on the semiconductor layer 121 . The first insulating layer 122 may insulate the gate electrode 123 from the semiconductor layer 121 . The first insulating layer 122 may be formed of an insulating material such as silicon nitride (SiNx) or silicon oxide (SiOx), and may also be formed of an insulating organic material. The first insulating layer 122 may include second holes to electrically connect each of the source electrode 125S and the drain electrode 125D with the semiconductor layer 121 .

A gate electrode 123 may be disposed on the first insulating layer 122 to overlap the semiconductor layer 121 in the display area AA. The gate electrode 123 is made of molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al), chromium (Cr), gold (Au), nickel (Ni), neodymium (Nd), tungsten (W) , And may be formed of a single layer or multiple layers made of any one of gold (Au) or an alloy thereof.

A second insulating layer 124 may be disposed on the gate electrode 123 . The second insulating layer 124 may be formed of an insulating material such as silicon nitride (SiNx) or silicon oxide (SiOx), and may also be formed of an insulating organic material. The second insulating layer 124 may include second holes to electrically connect each of the source electrode 125S and the drain electrode 125D with the semiconductor layer 121 .

A source electrode 125S and a drain electrode 125D may be disposed in the display area AA on the second insulating layer 124 .

The source electrode 125S and the drain electrode 125D disposed in the display area AA are electrically connected to the semiconductor layer 121 through second holes of the first insulating layer 122 and the second insulating layer 124. do.

The source electrode 125S and the drain electrode 125D include molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al), chromium (Cr), gold (Au), nickel (Ni), and neodymium (Nd). ) may be formed as a single layer or multi-layer made of any one or an alloy thereof, but is not limited thereto. For example, the source electrode 125S and the drain electrode 125D may have a three-layer structure of titanium (Ti)/aluminum (Al)/titanium (Ti) made of a conductive metal material, but is not limited thereto.

A protective layer 126 may be disposed on the thin film transistor 120 . The protective layer 126 may be disposed in some areas of the display area AA and the non-display area NA.

The protective layer 126 may protect the thin film transistor 120 . The protective layer 126 may be formed of an insulating material such as silicon nitride (SiNx) or silicon oxide (SiOx), and may also be formed of an insulating organic material.

The protective layer 126 may have a third hole to connect the anode electrode 210 of the light emitting element layer 200 and the thin film transistor 120 . The protective layer 126 is not a necessary component and may be omitted according to the design of the display device 100 .

A first planarization layer 130 may be disposed on the protective layer 126 . The first planarization layer 130 may be disposed to cover the thin film transistor 120 .

The first planarization layer 130 may be disposed in some areas of the display area AA and the non-display area NA. For example, the first planarization layer 130 may be disposed in the bending area BA of the non-display area NA.

The first planarization layer 130 may protect thin film transistors disposed therebelow and alleviate or planarize steps caused by various patterns.

The first planarization layer 130 is made of at least one of an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, a polyimide resin, an unsaturated polyester resin, a polyphenylene resin, and a polyphenylene sulfide resin. It may be formed, but is not limited thereto.

In the first planarization layer 130, a connection electrode 140 electrically connecting the anode electrode 210 of the light emitting element layer 200 and the source electrode 125S or drain electrode 125D of the thin film transistor 120 is disposed. To do so, a third hole may be provided.

A connection electrode 140 may be disposed on the first planarization layer 130 .

A third hole is formed in the first planarization layer 130, and a connection electrode 140 is further disposed on top of the first planarization layer 130 or in the third hole, so that the thin film transistor 120 passes through the connection electrode 140. ) and the light emitting element layer 200 may be electrically connected. For example, one end (or part or one side) of the connection electrode 140 is electrically connected to the thin film transistor 120, and the other end (or other part or other side) of the connection electrode 140 is the light emitting element layer 200 It is electrically connected to, and a current and a signal of the thin film transistor 120 may be transmitted to the light emitting element layer 200 through the connection electrode 126 .

The connection electrode 140 is any one of molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al) chromium (Cr), gold (Au), nickel (Ni), and neodymium (Nd), or these It may be formed of a single layer or multiple layers made of an alloy of. For example, the connection electrode 140 may have a three-layer structure of titanium (Ti)/aluminum (Al)/titanium (Ti) made of a conductive metal material, but is not limited thereto.

The planarization layer may be disposed as a single layer, but may be disposed as a plurality of layers of two or more layers in consideration of the arrangement of electrodes. This is due to the increase in various signal lines as the display device 100 evolves to a high resolution. Therefore, it was difficult to place all the wires on one layer with minimum spacing, so an additional layer was created. The additional layer frees up wiring layout, making wire/electrode layout design easier. In addition, when a dielectric material is used as a planarization layer composed of multiple layers, the planarization layer may be used for forming capacitance between metal layers.

A second planarization layer 150 may be disposed on the first planarization layer 130 and the connection electrode 140 .

The second planarization layer 150 may be disposed in some areas of the display area AA and the non-display area NA. For example, the second planarization layer 150 may be disposed in the bending area BA of the non-display area NA.

The second planarization layer 150 may protect thin film transistors disposed therebelow and alleviate or planarize steps caused by various patterns.

The second planarization layer 150 is made of at least one of acrylic resin, epoxy resin, phenol resin, polyamide resin, polyimide resin, unsaturated polyester resin, polyphenylene resin, and polyphenylene sulfide resin. It may be formed, but is not limited thereto.

The second planarization layer 150 may have a fourth hole to electrically connect the anode electrode 210 and the connection electrode 140 of the light emitting device layer 200 .

The light emitting device layer 200 may be disposed on the second planarization layer 150 . The light emitting element layer 200 includes an anode electrode 210 , a light emitting layer 230 , and a cathode electrode 240 . The light emitting element layer 200 may be formed by disposing an anode electrode 210 , a light emitting layer 230 , and a cathode 240 sequentially on the second planarization layer 150 .

The anode electrode 210 may be disposed on the second planarization layer 150 . The anode electrode 210 is electrically connected to the connection electrode 140 through the fourth hole of the second planarization layer 150 . The anode electrode 210 may be electrically connected to the drain electrode 125D through the connection electrode 140 .

The anode electrode 210 supplies holes to the light emitting layer 230 and may be made of a conductive material having a high work function.

When the display device 100 is a top emission type, the anode electrode 210 is a reflective electrode that reflects light and may be disposed using an opaque conductive material. For example, the anode electrode 210 is formed of at least one of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or alloys thereof. It may be, but is not limited thereto.

For example, the anode electrode 210 may have a three-layer structure of silver (Ag)/lead (Pd)/copper (Cu), but is not limited thereto.

An emission layer 230 may be disposed on the anode electrode 210 . The light emitting layer 230 may include one of a red organic light emitting layer, a green organic light emitting layer, a blue organic light emitting layer, and a white organic light emitting layer in order to emit light of a specific color. When the light emitting layer 230 includes a white organic light emitting layer, a color filter for converting white light from the white organic light emitting layer into light of a different color may be disposed on the light emitting device layer 200 . In addition, the light emitting layer 230 may further include a hole injection layer, a hole transport layer, an electron transport layer, and an electron transport layer in addition to the organic light emitting layer. there is.

A cathode electrode 240 may be disposed on the light emitting layer 230 . The cathode electrode 240 supplies electrons to the light emitting layer 230 and may be made of a conductive material having a low work function.

When the display device 100 is a top emission type, the cathode electrode 240 may be disposed using a transparent conductive material that transmits light. For example, it may be formed of at least one of indium tin oxide (ITO) and indium zinc oxide (IZO), but is not limited thereto.

In addition, it may be disposed using a translucent conductive material that transmits light. For example, with at least one or more alloys such as LiF/Al, CsF/Al, Mg:Ag, Ca/Ag, Ca:Ag, LiF/Mg:Ag, LiF/Ca/Ag, and LiF/Ca:Ag. can be formed, but is not limited thereto.

The bank layer 220 may be disposed on the anode electrode 210 and the second planarization layer 150 .

The bank layer 220 can distinguish a plurality of sub-pixels SP, minimize light blurring, and prevent color mixing occurring at various viewing angles.

The bank layer 220 may have a bank hole exposing the anode electrode 210 corresponding to the light emitting region.

The bank layer 220 may be formed of at least one of an inorganic insulating material such as silicon nitride (SiNx) or silicon oxide (SiOx) or an organic insulating material such as BCB (BenzoCycloButene), acrylic resin, or imide resin. It is not limited.

A spacer may be further disposed on the bank layer 220 . The spacer may buffer an empty space between the substrate 110 on which the light emitting device layer 200 is formed and the upper substrate, thereby minimizing damage to the display device 100 from impact from the outside. The spacer may be formed of the same material as the bank layer 220 and may be formed simultaneously with the bank layer 220, but is not limited thereto.

A protective layer 160 may be further disposed on the cathode electrode 240 of the light emitting device layer 200 to protect it from external moisture or foreign substances. The protective layer 160 may be made of a transparent material to transmit light emitted from the light emitting layer 230 .

The protective layer 200 may have a three-layer structure of inorganic film/organic film/inorganic film, and the inorganic film may be made of at least one inorganic material selected from silicon nitride (SiNx), silicon oxide (SiOx) and aluminum oxide (AlyOz), It is not limited to this.

A pad part 114 and a gate driver 112 may be disposed in the non-display area AA.

A pad part 114 may be disposed on one side of the substrate 110 in the non-display area AA. The non-display area NA where the pad part 114 is disposed by the bending process of the substrate 110 may be located on the rear surface of the substrate 1100 where an image is not displayed.

The pad part 114 may include a signal pad SP and a pad electrode PE connected to the signal pad SP. The pad unit 114 may be configured to transfer a signal (voltage) from an external module bonded to the pad unit 114 to a circuit unit such as the display area AA or the gate driver 112 . The signal pad SP may be formed of the same material and the same process as the gate electrode 123 of the thin film transistor 120, but is not limited thereto. In addition, the pad electrode PE may be formed of the same material and the same process as the source electrode 125S and the drain electrode 125D of the thin film transistor 120, but is not limited thereto.

The connection wiring part 300 and the first planarization layer 130 may be disposed in the bending area BA where the substrate is bent by the bending process in the non-display area NA.

The connection wiring unit 300 transfers a signal (voltage) from an external module bonded to the pad unit 114 to a circuit unit such as the display area AA or the gate driver 112 . For example, various signals such as various signals for driving the gate driver 112 , data signals, high potential voltages, and low potential voltages may be transmitted through the connection wiring unit 300 .

The bending area BA of the present specification undergoes a bending process of bending the substrate after forming various wires and components on the substrate. Tensile force is applied to the bending area BA formed during the bending process or after the bending process, and thus, cracks and disconnection may occur in the connection wiring part due to mechanical stress.

The tensile force may be an external force that acts when an object is bent, stretched, or pulled. Stress is a resistance generated in an object when an external force such as tensile force, compression, or torsion acts on the object.

For example, the tensile force of the connection wiring part 300 may be differently received according to the bending curvature of the substrate in the bending area. The bending curvature indicates the degree of bending of the curve, and the value of the bending curvature may be inversely proportional to the radius of curvature or the radius of curvature. For example, when the radius of curvature or the radius of curvature is large, the curvature value may be relatively low, and when the radius of curvature or the radius of curvature is small, the curvature value may be relatively high.

When the connection wiring part is formed in a straight line with one wire, the part having a large bending curvature among the connection wiring parts disposed in the bending area BA receives a large tensile force, so stress is generated in the connection wiring part and this stress Due to this, cracks and disconnection may occur.

When a crack occurs in a corresponding connection wiring part among at least one connection wiring part, a signal (voltage) from an external module may not be transferred to the display area AA. Since normal signal transfer is not performed, the thin film transistor 120 or the light emitting element layer 200 disposed in the display area AA may not operate normally, which may lead to defects in the display device.

Accordingly, in the display device 100 according to the exemplary embodiment of the present specification, the connection wiring unit 300 disposed in the bending area BA may be disposed as a double wire.

For example, the connection wiring unit 300 may include a first connection wiring 310 , a second connection wiring 320 , and a first planarization layer 130 . Accordingly, the connection wiring unit 300 may constitute a double wiring.

FIG. 4 is an enlarged plan view of a part of the bending area of FIG. 3 . 4 is a plan view illustrating that the first connection wire 310 and the second connection wire 320 of the connection wire unit 300 are arranged in a pattern shape. 4 will be described together to describe the pattern shapes of the first connection wire 310 and the second connection wire 320 .

The first connection wire 310 may transfer a signal (or voltage) from an external module bonded to the pad unit 114 to a circuit unit such as the display area AA or the gate driver 112 .

When the first connection wire 310 in the bending area BA is formed as one continuous wire between the pad part 114 disposed on one side of the non-display area NA in the display area AA, the bending area Among the connection wiring parts disposed at BA, since the connection wiring receives a large tensile force in a portion having a large bending curvature, cracks may occur. Accordingly, the first connection wires 310 may be spaced apart from each other with the first planarization layer 130 interposed therebetween in a pattern shape. For example, the first connection wire 310 has at least two or more patterns, and the plurality of patterns are disposed separately from each other. Accordingly, it is possible to prevent cracks and disconnection in a portion having a large bending curvature among the connection wiring portions disposed in the bending area BA.

When the first connection wire 310 is arranged in a pattern, the tensile force acting on the first connection wire 310 disposed in the bending area is dispersed by the bending process, as opposed to continuously forming one wire. can Accordingly, mechanical stress applied to the connection wiring unit 300 is reduced, and thus reliability of the display device 100 may be prevented from being deteriorated due to cracks or disconnection of the first connection wiring 310 .

The first connection wire 310 may be formed of the same material and the same process as the source electrode 125S and the drain electrode 125D of the thin film transistor 120 disposed in the display area AA, but is not limited thereto. .

For example, the first connection wire 310 may include molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al), chromium (Cr), gold (Au), nickel (Ni), and neodymium (Nd). ) may be formed as a single layer or multi-layer made of any one or an alloy thereof, but is not limited thereto. For example, the first connection wire 310 may have a three-layer structure of titanium (Ti)/aluminum (Al)/titanium (Ti) made of a conductive metal material, but is not limited thereto.

A first planarization layer 130 may be disposed on the first connection wire 310 . The first planarization layer 130 may protect the first connection wire 310 by filling the spaced apart space of the first connection wire 310 configured in a pattern shape and covering the first connection wire 310 .

The first planarization layer 130 may be formed simultaneously with the same material and the same process during the process of forming the first planarization layer on the thin film transistor 120 disposed in the display area AA of the display device 100. It is not necessarily limited thereto, and may be formed through patterning by performing a separate process during the process.

The first planarization layer 130 may further include a plurality of first holes H exposing at least a portion of the first connection wire 310 . The first hole H may be a hole, but is not limited to the term.

The first connection wiring 310 disposed under the first planarization layer 130 and the second connection wire 310 disposed above the first planarization layer 130 through the first holes H of the first planarization layer 130 . The connection wire 320 may be electrically connected.

A second connection wire 320 may be disposed on the first planarization layer 130 . The second connection wire 320 may electrically connect each pattern of the first connection wire 310 formed in a pattern so that the tensile force acting on the first connection wire 310 is dispersed. For example, since the first connection wires 310 are arranged in a plurality of patterns of at least two or more, and the patterns of the first connection wires 310 are formed separately from each other, signals from the pad part 114 are transmitted to the display area. In order to transfer to (AA), the patterns of the first connection wire must be electrically connected.

The second connection wire 320 may electrically connect patterns of the first connection wire 310 through the first holes H of the first planarization layer 130 . For example, the second connection wire 320 may be an upper portion of the first planarization layer 130, an upper portion of the first connection wire 310 exposed by the first hole H of the first planarization layer 130, And it may be disposed on the inclined surface of the first planarization layer 130 formed by the first hole H of the first planarization layer 130 .

When the second connection wire 320 disposed in the bending area BA is formed as one continuous wire between the pad part 114 disposed on one side of the non-display area NA in the display area AA, Among the connection wiring parts disposed in the bending area BA, since the connection wiring receives a large tensile force in a portion having a large bending curvature, cracks may occur. Accordingly, the second connection wires 320 may be arranged in a pattern shape. For example, the second connection wire 320 has a plurality of patterns, and the patterns of the second connection wire 320 are formed separately from each other. Accordingly, it is possible to prevent cracks and disconnection in a portion having a large bending curvature among the connection wiring portions disposed in the bending area BA.

When the second connection wire 320 is arranged in a pattern shape, as opposed to continuously forming one wire in the bending area BA, the second connection wire 320 disposed in the bending area by the bending process The acting tensile force can be dissipated. Accordingly, mechanical stress applied to the connection wire 300 is reduced, and thus reliability of the display device 100 may be prevented from deteriorating due to cracks or disconnection of the second connection wire 320 .

Each pattern of the second connection wire 320 may include one side connection portion (or first portion) and another side connection portion (or second portion) spaced apart from the one side connection portion. For example, each pattern of the second connection wire 320 includes one connection part (or first part) at one end, and the other connection part (second part) at the other end opposite to one end. can include One connection part (or first part) and the other connection part (or second part) of each pattern of the second connection wire 320 are parts disposed in the first holes H of the first planarization layer 130. .

One connection part (or first part) and the other connection part (or second part) of each pattern of the second connection wire 320 may be electrically connected to different patterns of the first connection wire 310 . The patterns of the first connection wire 310 are spaced apart from each other, and may be connected to one connection part (or first part) and the other connection part (or second part) of each pattern of the second connection wire 320, respectively. .

The second connection wire 320 may be formed of the same material and the same process as the connection electrode 140 disposed in the display area AA, but is not limited thereto.

For example, the second connection wire 320 includes molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al), chromium (Cr), gold (Au), nickel (Ni), and neodymium (Nd). ) may be formed as a single layer or multi-layer made of any one or an alloy thereof, but is not limited thereto. For example, the second connection wire 320 may have a three-layer structure of titanium (Ti)/aluminum (Al)/titanium (Ti) made of a conductive metal material, but is not limited thereto.

A second planarization layer 150 may be further disposed on the second connection wire 320 and the first planarization layer 130 . The second planarization layer 150 may protect the second connection wire 310 by covering the second connection wire 320 .

The second planarization layer 150 may be formed at the same time using the same material and process during the process of forming the planarization layer on the connection electrode 140 disposed in the display area AA of the display device 100. It is not limited, and may be provided through patterning by performing a separate process during the process.

FIG. 5 is an enlarged cross-sectional view of a portion of the bending area of FIG. 3 .

Referring to FIG. 5 , the angle θ between the inclined surface of the first planarization layer 130 formed by the first hole H of the first planarization layer 130 and the first connection wire 310 is 45° or more. and 60 degrees or less.

The angle of the slope formed by the first hole H of the first flattening layer 130 is set to prevent a problem in which the first connection wire and the second connection wire are not connected or disconnected in the bending area BA. can

The first planarization layer 130 disposed between the first connection wire 310 and the second connection wire 320 may electrically connect the first connection wire 310 and the second connection wire 320 to the first flattening layer 130 . It includes a hole (H).

A second connection wire 320 is disposed inside the first hole H of the first planarization layer 130 to be electrically connected to the first connection wire 310. Depending on the angle of the inclined surface of the hole H, cracks or disconnection may occur when the second connection pattern 320 is connected to the first connection wire.

The second connection wire 320 is formed on the top of the first planarization layer 130, the top of the first connection wire 310 exposed by the first hole H of the first planarization layer 130, and the first planarization layer 130. It may be disposed on an inclined surface of the first planarization layer 130 formed by the first hole H of the layer 130 .

The inclined surface of the first planarization layer 130 formed by the first hole H and the first connection wire 310 may form a predetermined taper angle θ.

A taper angle θ between the inclined surface of the first planarization layer 130 and the first connection wire 310 may be greater than or equal to 45 degrees and less than or equal to 60 degrees. For example, the angle θ between the inclined surface of the hole of the first planarization layer 130 and the first connection wire 310 may be the angle of the portion where the first planarization layer 130 is formed. When the taper angle θ between the inclined surface of the first planarization layer 130 and the first connection wire 310 is less than 45°, the length of the inclined surface of the first planarization layer 130 becomes long, and the first planarization layer The length of each pattern of the second connection wire 320 formed on the inclined surface of (130) is formed long in a straight line. In this way, when the length of each pattern of the second connection wires 320 disposed on the inclined surface of the first flattening layer 130 is formed to be long in a straight line, the second connection disposed in a portion having a large bending curvature among the bending areas BA. Each pattern of the wiring 320 receives a tensile force due to a bending process, and cracks or disconnection may occur.

In addition, when the taper angle θ between the inclined surface of the first planarization layer 130 and the first connection wire 310 exceeds 60 degrees, during the process of forming the second connection wire 320, the first planarization layer The taper angle of (130) is high, and disconnection may occur.

For example, the first planarization layer 130 has a relatively thick thickness compared to other elements constituting the display device 100 . The second connection wiring 320 is formed through a patterning process in which a metal material is applied on the first planarization layer 130 and then cured. At a high angle of the slope of the first planarization layer 130, the metal material is cured before the metal material is cured. Due to the high angle of the first planarization layer, it flows down and is not coated on the inclined surface, so that the second connection wire may be disconnected.

Therefore, since the taper angle θ of the first flattening layer 130 is formed to be 45 degrees or more and 60 degrees or less, cracks or disconnection problems of the double wiring of the connection wiring unit 300 of the present specification can be effectively prevented. .

A coating layer may be further disposed on the upper portion of the substrate 110 corresponding to the bending area BA to prevent cracks and disconnection of various wires located on the bending area BA. The coating layer may be a micro coating layer (MCL), and the term is not limited thereto.

For example, since the coating layer may cause fine cracks due to tensile force acting on the connection wiring unit 300 disposed on the substrate 110 when the substrate is bent, resin is applied with a thin thickness at the bending position. It can serve as a coating to protect the wiring.

The coating layer may be disposed on various wire forming parts such as data wires, high potential voltage wires, and low potential voltage wires formed on the bending area BA to adjust the positions of the wires to be closer to the neutral line during bending. there is. Accordingly, durability of the wires may be improved by applying a minimum tensile stress formed above the neutral wire and contractive stress formed below the neutral wire to the wires. In addition, the coating layer may also include physical and chemical protective functions capable of protecting various wires disposed on the flexible substrate 110 from external impact, moisture, or dust during the manufacturing process.

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 a substrate including a display area, a non-display area adjacent to the display area, and a bending area provided in at least a portion of the non-display area, a first connection wire disposed in the bending area on the substrate, and a first connection line on the substrate. It may include a first planarization layer disposed on one connection wire, and a second connection wire disposed on the first planarization layer.

According to some embodiments of the present specification, the first planarization layer may include a hole, and the first connection wire and the second connection wire may be electrically connected through the hole.

According to some embodiments of the present specification, the first connection wire may include a plurality of patterns.

According to some embodiments of the present specification, the second connection wire includes a plurality of patterns, and each pattern of the second connection wire has one connection portion at one end and the other end opposite to the one end. It includes the other connection part, and the one connection part and the other connection part may be electrically connected to different patterns of the first connection wire.

According to some embodiments of the present specification, an angle θ formed between the inclined surface of the hole of the first planarization layer and the first connection wire may be 45° or more and 60° or less.

According to some embodiments of the present specification, an angle θ formed between an inclined surface of the hole of the first planarization layer and the first connection wire may be an angle of a portion where the first planarization layer is formed.

According to some embodiments of the present specification, it may further include a thin film transistor disposed on a substrate in the display area, a connection electrode connected to the thin film transistor, and a second planarization layer disposed on the second connection line in the non-display area. there is.

According to some embodiments of the present specification, the thin film transistor may further include a semiconductor layer, a gate electrode on the semiconductor, and source and drain electrodes on the gate electrode.

According to some embodiments of the present specification, the first connection wire may be formed through the same process as the source and drain electrodes.

According to some embodiments of the present specification, the second connection wire may be formed through the same process as the connection electrode.

According to some embodiments of the present specification, a light emitting element layer may be further included on the second planarization layer.

According to some embodiments of the present specification, a substrate including a display area, a non-display area adjacent to the display area, and a bending area in at least a portion of the non-display area, a thin film transistor disposed in the display area, and a first substrate disposed in the bending area. 1 connection wire, a first planarization layer disposed on the thin film transistor in the display area and the first connection wire in the bending area, and a connection electrode disposed in the display area on the first planarization layer and a second connection wire disposed on the bending area can include

According to some embodiments of the present specification, the first planarization layer may include a hole, and the first connection wire and the second connection wire may be electrically connected through the hole.

According to some embodiments of the present specification, an angle θ formed between the inclined surface of the hole of the first planarization layer and the first connection wire may be 45° or more and 60° or less.

According to some embodiments of the present specification, the first connection wire may include a plurality of patterns.

According to some embodiments of the present specification, the second connection wire includes one side connection portion and the other connection portion spaced apart from the one side connection portion, and the one side connection portion and the other connection portion are different from each other in patterns of the first connection wire, respectively. can be electrically connected.

According to some embodiments of the present specification, the thin film transistor may further include a semiconductor layer, a gate electrode on the semiconductor, and source and drain electrodes on the gate electrode.

According to some embodiments of the present specification, the first connection wire may be formed through the same process as the source and drain electrodes.

According to some embodiments of the present specification, the second connection wire may be formed through the same process as the connection electrode.

According to some embodiments of the present specification, a second planarization layer disposed in the display area and the bending area and on the second connection line, and a light emitting element layer disposed on the second planarization layer may be included.

Although the embodiments of this specification have been described in more detail with reference to the accompanying drawings, the present specification is not necessarily limited to these embodiments, and may be variously modified and implemented without departing from the technical spirit of the present specification. . Therefore, the embodiments disclosed in this specification are not intended to limit the technical spirit of the present specification, but to explain, and the scope of the technical spirit of the present specification is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of this specification should be construed by the scope of the claims, and all technical ideas within the equivalent range should be construed as being included in the scope of rights of this specification.

100: display device
110: substrate
120: thin film transistor
130: first planarization layer
140: connection electrode
150: second planarization layer
310: first connection wire
320: second connection wire

Claims (20)

a substrate including a display area, a non-display area adjacent to the display area, and a bending area provided in at least a portion of the non-display area;
a first connection wire disposed in the bending area on the substrate;
a first planarization layer disposed on the first connection wire; and
and a second connection wire disposed on the first planarization layer. According to claim 1,
The display device of claim 1 , wherein the first planarization layer includes a hole, and the first connection wire and the second connection wire are electrically connected through the hole. According to claim 1,
The first connection wire includes a plurality of patterns. According to claim 3,
The second connection wire includes a plurality of patterns,
Each pattern of the second connection wire includes one connection portion at one end portion; And a second connection part at the other end opposite to the one end,
The one-side connection portion and the other-side connection portion are electrically connected to different patterns of the first connection wire, respectively. According to claim 2,
An angle θ formed between an inclined surface of the hole of the first planarization layer and the first connection wire is 45 degrees or more and 60 degrees or less, the display device. According to claim 5,
An angle θ formed between an inclined surface of the hole of the first planarization layer and the first connection wire is an angle of a portion where the first planarization layer is formed. According to claim 1,
a thin film transistor disposed on the substrate of the display area;
a connection electrode connected to the thin film transistor; and
and a second planarization layer disposed on the second connection wire in the non-display area. According to claim 7,
The thin film transistor further includes a semiconductor layer, a gate electrode on the semiconductor, and source and drain electrodes on the gate electrode. According to claim 8,
The first connection wire is formed in the same process as the source and drain electrodes. According to claim 7,
The second connection wire is formed in the same process as the connection electrode. According to claim 7,
Further comprising a light emitting element layer on the second planarization layer, the display device. a substrate including a display area, a non-display area adjacent to the display area, and a bending area in at least a portion of the non-display area;
a thin film transistor disposed in the display area and a first connection wire disposed in the bending area;
a first planarization layer disposed on the thin film transistor of the display area and the first connection line of the bending area; and
and a connection electrode disposed on the first planarization layer in the display area and a second connection wire disposed on the bending area. According to claim 12,
The display device of claim 1 , wherein the first planarization layer includes a hole, and the first connection wire and the second connection wire are electrically connected through the hole. According to claim 12,
An angle θ formed between an inclined surface of the hole of the first planarization layer and the first connection wire is 45° or more and 60° or less, the display device. According to claim 12,
The first connection wire includes a plurality of patterns. According to claim 12,
The second connection wire includes one side connection portion and the other side connection portion spaced apart from the one side connection portion, and the one side connection portion and the other side connection portion are electrically connected to different patterns of the first connection wire, respectively. , display device. According to claim 12,
The thin film transistor further includes a semiconductor layer, a gate electrode on the semiconductor, and source and drain electrodes on the gate electrode. According to claim 17,
The first connection wire is formed in the same process as the source and drain electrodes. According to claim 12,
The second connection wire is formed in the same process as the connection electrode. According to claim 12,
a second planarization layer disposed in the display area and the bending area and on the second connection wire; and
A display device comprising a light emitting element layer disposed on the second planarization layer.

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