KR102583815B1 - Flexible display device and method for manufacturing thereof - Google Patents

Abstract

The present invention relates to a flexible display device and a manufacturing method thereof that prevent reliability from being reduced when bonded to an upper substrate by flattening the lower substrate.
The present invention includes a display panel divided into a display area where pixels are arranged and a non-display area provided outside the display area. This display panel includes a first substrate, a thin film transistor layer, an organic light emitting device layer, an organic encapsulation film in a display area, and an edge planarization film in a non-display area. The height of the edge planarization film is flattened with the heights of the thin film transistor layer, the organic light emitting device layer, and the organic encapsulation film in the display area.

Description

Flexible display device and manufacturing method thereof {FLEXIBLE DISPLAY DEVICE AND METHOD FOR MANUFACTURING THEREOF}

The present invention relates to a display device and a method of manufacturing the same, and more specifically, to a display device based on a flexible substrate and a method of manufacturing the same.

Flexible display devices are attracting attention as next-generation display devices because pixel cells are implemented on a thin flexible substrate such as plastic and have the advantage of being able to display desired images even when folded or rolled like paper. It is being received, and research and development on this is in progress.

The flexible display device includes a flexible liquid crystal display device, a flexible plasma display device, a flexible organic light emitting display device, and a flexible electrophoresis display device. An electrophoretic display device, a flexible electro-wetting display device, etc. may be included.

Among the flexible display devices, in particular, organic light emitting display devices are attracting attention as next-generation flexible display devices because they have a high-speed response time of 1 ms or less, low power consumption, and are capable of self-emitting light.

A conventional flexible display device is constructed by bonding a lower substrate and an upper substrate. Recently, there has been a lot of demand for high-resolution flexible display devices. In order to implement a high-resolution display device, the cell gap between the lower substrate and the upper substrate must be configured to be low to secure the viewing angle of the pixel. In order to configure the cell gap between the lower substrate and the upper substrate to be low, the thickness of the adhesive layer disposed between the lower substrate and the upper substrate must be thinner to bond the lower substrate and the upper substrate. However, since the display area of the lower substrate requires a certain thickness or more to form the organic light-emitting layer, a large thickness difference occurs between the display area and the non-display area where the organic light-emitting layer is not formed. Therefore, in order to bond a lower substrate having a display area and a non-display area with a large difference in thickness to the upper substrate, an adhesive layer thickness exceeding a certain thickness is required, making it impossible to configure the cell gap to be low. When a lower substrate with a large difference in thickness between the display area and the non-display area is bonded to the upper substrate with a thin adhesive layer, a non-bonded area may occur in the non-display area. In such a conventional flexible display device, cracks may occur in the wiring during post-processing due to non-bonding areas, and the reliability of the display device may decrease.

The present invention was developed to solve the above-mentioned problems, and its technical task is to provide a flexible display device and a manufacturing method thereof that prevent reliability from being reduced when bonded to an upper substrate by flattening the lower substrate.

The present invention for achieving the above-described technical problem includes a display panel divided into a display area where pixels are arranged and a non-display area provided outside the display area. This display panel includes a first substrate, a thin film transistor layer, an organic light emitting device layer, an organic encapsulation film in a display area, and an edge planarization film in a non-display area. The present invention provides a flexible display device in which the height of the edge planarization film is planarized with the height of the thin film transistor layer, the organic light emitting device layer, and the organic encapsulation film in the display area, and a method of manufacturing the same.

According to the present invention, the flexible display device of the present invention reduces the difference in thickness between the display area and the non-display area of the first substrate by disposing the edge planarization film in the non-display area.

In addition, the flexible display device of the present invention has a low cell gap between the first and second substrates by arranging a thin resin layer, and thus, it is possible to secure the viewing angle of the pixel, thereby realizing a high-resolution flexible display device. .

In addition, the flexible display device of the present invention distributes the resin layer thinly and evenly between the planarized first and second substrates, thereby preventing the occurrence of non-bonded areas.

In addition, the flexible display device of the present invention can prevent cracks and peeling of wiring that may occur during post-processing due to non-bonded areas, thereby preventing the reliability of the flexible display device from being deteriorated. It can be prevented.

Additionally, the flexible display device of the present invention can more effectively prevent moisture from penetrating into the display panel from the outside by disposing a plurality of first organic layers.

Additionally, the manufacturing method of the flexible display device of the present invention can flatten the display area and non-display area of the first substrate using existing processes without adding additional processes.

The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. .

1 is a perspective view showing a flexible display device according to an example of the present invention.
FIG. 2 is a plan view showing the display area, non-display area, gate driver, source drive IC, flexible film, circuit board, and timing control unit of the first substrate of FIG. 1.
Figure 3 is a cross-sectional view of a flexible display device according to a first example of the present invention.
Figure 4 is a cross-sectional view of a flexible display device according to a second example of the present invention.
5A to 5G are cross-sectional views for explaining a method of manufacturing a flexible display device according to an example of the present invention.

The meaning of terms described in this specification should be understood as follows.

Singular expressions should be understood to include plural expressions unless the context clearly defines otherwise, and terms such as “first”, “second”, etc. are used to distinguish one element from another element. The scope of rights should not be limited by these terms. Terms such as “include” or “have” should be understood as not precluding the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. The term “at least one” should be understood to include all possible combinations from one or more related items. For example, “at least one of the first, second, and third items” means each of the first, second, or third items, as well as two of the first, second, and third items. It means a combination of all items that can be presented from more than one. The term “on” means not only the case where a component is formed directly on top of another component, but also the case where a third component is interposed between these components.

Hereinafter, a preferred example of the flexible display device and its manufacturing method according to the present invention will be described in detail with reference to the attached drawings. In adding reference numerals to components in each drawing, identical components may have the same reference numerals as much as possible even if they are shown in different drawings. Additionally, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description may be omitted.

Figure 1 is a perspective view showing a flexible display device according to an example of the present invention, and Figure 2 is a display area and a non-display area of the first substrate of Figure 1, a gate driver, source drive IC, flexible film, circuit board, and timing. This is a floor plan showing the control unit. 1 and 2, the X-axis represents a direction parallel to the gate line, the Y-axis represents a direction parallel to the data line, and the Z-axis represents the height direction of the flexible display device.

Referring to FIGS. 1 and 2 , the flexible display device according to an example of the present invention includes a display panel 100, a gate driver 200, and a source drive integrated circuit (hereinafter referred to as “IC”) 310. , a flexible film 330, a circuit board 350, and a timing control unit 400.

The display panel 100 includes a first substrate 110 and a second substrate 190. Gate lines, data lines, and pixels are formed on one side of the first substrate 110 facing the second substrate 190. The pixels include a plurality of sub-pixels, and the plurality of sub-pixels are formed in intersection areas of gate lines and data lines.

Each of the plurality of sub-pixels may include at least one thin film transistor and an organic light emitting device. Each of the plurality of sub-pixels receives a data voltage through a data line when at least one thin film transistor is turned on by a gate signal of the gate line. Each of the plurality of sub-pixels controls the current flowing to the organic light-emitting device according to the data voltage, causing the organic light-emitting device to emit light at a predetermined brightness.

As shown in FIG. 2, the display panel 100 can be divided into a display area (DA) that displays images and a non-display area (NDA) that does not display images. Gate lines, data lines, and pixels may be formed in the display area DA. A gate driver 200 and pads may be formed in the non-display area NDA. This display panel 100 is described in detail with reference to examples in FIGS. 3 and 4.

The gate driver 200 supplies gate signals to the gate lines according to the gate control signal input from the timing controller 400. The gate driver 200 may be formed in a non-display area (NDA) outside one or both sides of the display area (DA) of the display panel 100 using a gate driver in panel (GIP) method. Alternatively, the gate driver 200 is manufactured as a driving chip, mounted on a flexible film, and formed in a non-display area (NDA) outside one or both sides of the display area (DA) of the display panel 100 using a TAB (tape automated bonding) method. It may be attached to .

The source drive IC 310 receives digital video data and source control signals from the timing control unit 400. The source drive IC 310 converts digital video data into analog data voltages according to the source control signal and supplies them to the data lines. When the source drive IC 310 is manufactured as a driving chip, it can be mounted on the flexible film 330 using a COF (chip on film) or COP (chip on plastic) method.

Pads such as data pads may be formed in the non-display area NDA of the display panel 100. Wires connecting the pads and the source drive IC 310 and wires connecting the pads and the wires of the circuit board 350 may be formed in the flexible film 330. The flexible film 330 is attached to the pads using an anisotropic conducting film, so that the pads and the wiring of the flexible film 330 can be connected.

The circuit board 350 may be attached to the flexible films 330. The circuit board 350 may be equipped with multiple circuits implemented with driving chips. For example, the timing control unit 400 may be mounted on the circuit board 350. The circuit board 350 may be a printed circuit board or a flexible printed circuit board.

The timing control unit 400 receives digital video data and timing signals from an external system board through a cable of the circuit board 350. The timing control unit 400 generates a gate control signal for controlling the operation timing of the gate driver 200 and a source control signal for controlling the source drive ICs 310 based on the timing signal. The timing control unit 400 supplies a gate control signal to the gate driver 200 and a source control signal to the source drive ICs 310.

Figure 3 is a cross-sectional view of a flexible display device according to a first example of the present invention. This is a diagram schematically showing the cross section along II' shown in FIG. 2.

Referring to FIG. 3 , the flexible display device according to the first example of the present invention includes a first substrate 110, a resin layer 180, and a second substrate 190.

The first substrate 110 includes a display area (DA) and a non-display area (NDA). The display area DA has a plurality of pixels arranged horizontally and vertically. As such, the display area DA of the flexible display device according to the first example of the present invention includes a thin film transistor T disposed on the first substrate 110, a passivation layer (PAS), a planarization layer 120, and an organic It includes a light emitting device layer (OLED), a bank 140, a first inorganic layer 150, an organic encapsulation layer 160, and a second inorganic layer 170.

The first substrate 110 may be a flexible plastic film. For example, the first substrate 110 is a cellulose resin such as triacetyl cellulose (TAC) or diacetyl cellulose (DAC), cyclo olefin polymer (COP), cyclo olefin copolymer (COC) such as norbornene derivatives, etc. , acrylic resin such as PMMA (poly(methylmethacrylate)), polyolefin such as PC (polycarbonate), PE (polyethylene) or PP (polypropylene), PVA (polyvinyl alcohol), PES (poly ether sulfone), PEEK (polyetheretherketone) , It may be a sheet or film containing polyester such as PEI (polyetherimide), PEN (polyethylenenaphthalate), PET (polyethyleneterephthalate), PI (polyimide), PSF (polysulfone), or fluoride resin. , but is not limited to this.

A buffer layer may be additionally provided on the first substrate 110. The buffer layer may be provided on the entire upper surface of the first substrate 110. The buffer layer functions to prevent moisture from penetrating into the display panel 100 from the first substrate 110, which is vulnerable to moisture permeation. Additionally, the buffer layer functions to prevent impurities such as metal ions from diffusing from the first substrate 110 and penetrating into the active layer (ACT) of the thin film transistor (T). The buffer layer may be made of an inorganic insulating material, such as silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or multiple layers thereof, but is not limited thereto.

The thin film transistor T is disposed in the display area DA on the first substrate 110. The thin film transistor (T) includes an active layer (ACT), a gate insulating layer (GI), a gate electrode (GE), an interlayer insulating layer (ILD), a source electrode (SE), and a drain electrode (DE). The thin film transistor (T) may be composed of a thin film transistor layer together with a passivation layer (PAS).

The active layer ACT is provided on the first substrate 110 disposed in the display area DA. The active layer (ACT) is arranged to overlap the gate electrode (GE). The active layer (ACT) has one end area (A1) located on the source electrode (SE) side, the other end area (A2) located on the drain electrode (DE) side, and the center located between one end area (A1) and the other end area (A2). It may be composed of an area (A3). The central region A3 may be made of a semiconductor material that is not doped with a dopant, and the first region (A1) and the other end region (A2) may be made of a semiconductor material that is doped with a dopant.

The gate insulating layer (GI) is provided on the active layer (ACT). The gate insulating film (GI) functions to insulate the active layer (ACT) and the gate electrode (GE). The gate insulating film (GI) covers the active layer (ACT) and is formed on the entire display area (DA). The gate insulating film (GI) may be made of an inorganic insulating material, such as silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or multiple layers thereof, but is not limited thereto.

The gate electrode GE is provided on the gate insulating film GI. The gate electrode (GE) overlaps the central area (A3) of the active layer (ACT) with the gate insulating film (GI) interposed therebetween. The gate electrode (GE) is made of, for example, molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be a single layer or a multi-layer made of any one or an alloy thereof, but is not limited thereto.

An interlayer insulating layer (ILD) is provided on the gate electrode (GE). The interlayer insulating layer (ILD) is provided on the entire surface of the display area (DA) including the gate electrode (GE). The interlayer dielectric (ILD) may be made of the same inorganic insulating material as the gate insulating film (GI), such as silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or multiple layers thereof, but is limited thereto. It doesn't work.

The source electrode (SE) and drain electrode (DE) are arranged to be spaced apart from each other on the interlayer insulating layer (ILD). The above-described gate insulating film (GI) and interlayer insulating film (ILD) include a first contact hole (CNT1) exposing a part of one end area (A1) of the active layer (ACT) and a part of the other end area (A2) of the active layer (ACT). An exposed second contact hole (CNT2) is provided. The source electrode (SE) is connected to one end area (A1) of the active layer (ACT) through the first contact hole (CNT1), and the drain electrode (DE) is connected to the active layer (ACT) through the second contact hole (CNT2). It is connected to the other end area (A2).

The configuration of the thin film transistor T described above is not limited to the example described above, and can be modified in various ways to known configurations that can be easily implemented by those skilled in the art.

The passivation layer (PAS) is provided on the thin film transistor (T). The passivation layer (PAS) functions to protect the thin film transistor (T). The passivation layer (PAS) is provided in the display area (DA) on the first substrate 110. A passivation layer (PAS) is not provided in the non-display area (NDA) of the first substrate 110. The passivation layer (PAS) may be made of inorganic insulating materials such as silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or multiple layers thereof, but is not limited thereto.

The planarization layer 120 is provided on the thin film transistor layer, and more specifically, it is disposed between the thin film transistor layer and the organic light emitting device layer (OLED). The planarization layer 120 performs the function of flattening the upper part of the thin film transistor layer. The planarization layer 120 is made of an organic insulating material, such as acryl resin, epoxy resin, phenolic resin, polyamides resin, and polyimides resin. ), etc., but is not limited to this. The passivation layer (PAS) and the planarization layer 120 are provided with a third contact hole (CNT3) exposing the drain electrode (DE) of the thin film transistor (T). The drain electrode DE and the first electrode 130 are electrically connected through the third contact hole CNT3.

The organic light emitting device layer (OLED) is provided on the thin film transistor layer. The organic light emitting device layer (OLED) includes a first electrode 130, an organic light emitting layer (EL), and a second electrode (CAT).

The first electrode 130 is connected to the drain electrode DE of the thin film transistor T through the third contact hole CNT3 provided in the passivation layer PAS and the planarization layer 120. A bank 140 is provided between adjacent first electrodes 130 to partition the first electrodes 130. The bank 140 may electrically insulate the first electrodes 130 adjacent to each other. The bank 140 may be made of an organic insulating material, such as polyimides resin, acryl resin, or benzocyclobutene (BCB), but is not limited thereto.

The organic light emitting layer (EL) is provided on the first electrode 130. The organic light emitting layer (EL) may include a hole transporting layer, an organic light emitting layer, and an electron transporting layer. Furthermore, the organic light emitting layer (EL) may further include at least one functional layer to improve the luminous efficiency and/or lifespan of the light emitting layer.

The second electrode (CAT) is provided on the organic light emitting layer (EL) and the bank 140. When a voltage is applied to the first electrode 130 and the second electrode CAT, holes and electrons move to the light-emitting layer through the hole transport layer and the electron transport layer, respectively, and combine with each other in the light-emitting layer to emit light.

The first inorganic layer 150 is provided on the second electrode CAT. The first inorganic layer 150 includes a thin film transistor (T), a passivation layer (PAS), a planarization layer 120, a first electrode 130, an organic light emitting layer (EL), and a bank 140 disposed in the display area DA. ), sealing the second electrode (CAT). The first inorganic layer 150 may be made of an inorganic insulating material, such as silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or multiple layers thereof, but is not limited thereto.

The organic encapsulation film 160 is provided on the organic light emitting device layer (OLED) and the first inorganic film 150 disposed in the display area (DA). The organic encapsulation film 160 flattens the top of the second electrode CAT. Additionally, the organic encapsulation film 160 can prevent cracks from occurring in the first encapsulation layer 160 due to stress when the display panel 100 is bent or warped. The organic encapsulation film 160 is made of an organic insulating material, such as acryl resin, epoxy resin, phenolic resin, polyamides resin, and polyimides. resin), etc., but is not limited thereto.

The second inorganic layer 170 is provided on the first inorganic layer 150 and the organic encapsulation layer 160. The second inorganic layer 170 seals the first inorganic layer 150 and the organic encapsulation layer 160. Since the second inorganic film 170 seals the organic encapsulation film 160, moisture can be prevented from penetrating into the organic encapsulation film 160, which is vulnerable to moisture permeation. The second inorganic layer 170 may be made of the same material as the first inorganic layer 150, but is not limited thereto.

The non-display area (NDA) is provided outside the display area (DA). The non-display area (NDA) is formed with various pad electrodes and a driver for applying signals to the display area (DA), and the configuration of the non-display area (NDA) can be changed into various forms known in the art. As such, the non-display area (NDA) of the flexible display device according to the first example of the present invention includes an edge planarization film (EFF) disposed on the first substrate 110, a first inorganic film 150, and a second inorganic film 150. It includes an inorganic membrane (170).

The edge planarization film (EFF) is provided in the non-display area (NDA) on the first substrate 110. The height of the edge planarization film (EFF) is flattened with the height of the thin film transistor layer including the thin film transistor (T) in the display area (DA), the organic light emitting device layer (OLED), and the organic encapsulation film 160. The edge planarization film (EFF) includes a first organic film 125 and an inorganic encapsulation film 135.

The first organic layer 125 is provided in the non-display area NDA on the first substrate 110. The first organic layer 125 is provided to have a constant height from the first substrate 110 and functions to flatten the display area DA and the non-display area NDA of the first substrate 110. The first organic layer 125 may be made of the same material as the planarization layer 120 through the same process, but is not limited thereto.

The inorganic encapsulation film 135 is provided on the first organic film 125, and more specifically, is provided to surround the first organic film 125. Since the inorganic encapsulation film 135 seals the first organic film 125, moisture can be prevented from penetrating into the first organic film 125, which is vulnerable to moisture permeation. The inorganic encapsulation film 135 may be made of the same material and through the same process as the first electrode 130, but is not limited thereto.

The flexible display device according to the first example of the present invention arranges the edge planarization film (EFF) in the non-display area (NDA), thereby reducing the thickness of the display area (DA) and the non-display area (NDA) of the first substrate 110. Reduce the difference. A resin layer that bonds the second substrate 190 and the first substrate 110 on the first substrate 110, where the thickness difference between the display area (DA) and the non-display area (NDA) is reduced by the edge flattening film (EFF). (180) can be placed thinly. Accordingly, the flexible display device according to the first example of the present invention arranges the resin layer 180 to be thin to configure the cell gap between the first substrate 110 and the second substrate 190 to be low, and accordingly, the pixel It is possible to secure a viewing angle, making it possible to implement a high-resolution flexible display device. In addition, the flexible display device according to the first example of the present invention distributes the resin layer 180 thinly and evenly between the planarized first substrate 110 and the second substrate 190, thereby forming a non-bonded area that is not bonded. prevent occurrence. Therefore, the flexible display device according to the first example of the present invention can prevent cracks and peeling of the wiring that may occur during post-processing due to the non-bonding area, and thus, the flexible display device Reliability can be prevented from deteriorating.

The first inorganic layer 150 extends from the display area DA and seals the first organic layer 125 and the inorganic encapsulation layer 135 disposed in the non-display area NDA. The first inorganic layer 150 extends between the organic light emitting device layer (OLED) and the organic encapsulation layer 160 in the display area (DA) and covers the edge planarization film (EFF) in the non-display area (NDA).

The second inorganic layer 170 extends from the display area DA and seals the first organic layer 125, the inorganic encapsulation layer 135, and the first inorganic layer 150 disposed in the non-display area NDA. do. The second inorganic layer 170 covers the organic encapsulation layer 160 in the display area DA and the first inorganic layer 150 in the non-display area NDA. The second inorganic layer 170 may be made of the same material as the first inorganic layer 150, but is not limited thereto. However, when the first and second inorganic films 150 and 170 are made of the same material, the interfacial adhesion between the first and second inorganic films 150 and 170 may be improved. Accordingly, when the first and second inorganic films 150 and 170 are made of the same material, the inside of the display panel 100 from the outside is more visible than when the first and second inorganic films 150 and 170 are made of different materials. This can more effectively prevent moisture from penetrating. An inorganic layer or an organic layer may be additionally disposed on the second inorganic layer 170 .

The resin layer 180 is provided entirely on the encapsulation layer. The resin layer 180 is disposed between the first substrate 110 and the second substrate 190 to prevent light loss and increase the adhesive force between the first substrate 110 and the second substrate 190. In the flexible display device according to the first example of the present invention, the display area (DA) and the non-display area (NDA) of the first substrate 110 are flattened by the first organic layer 125, so that the resin layer 180 is disposed thinly to configure a low cell gap between the first substrate 110 and the second substrate 190. Accordingly, the viewing angle of the pixel can be secured, making it possible to implement a high-resolution flexible display device. In addition, the flexible display device according to the first example of the present invention distributes the resin layer 180 thinly and evenly between the planarized first substrate 110 and the second substrate 190, thereby forming a non-bonded area that is not bonded. prevent occurrence.

The second substrate 190 includes a color filter 191 and a touch array unit 195.

The color filter 191 is provided on the second substrate 190 to correspond to each pixel area. The color filter 260 may be made of red, green, and blue color filters corresponding to each pixel area, and a light blocking layer 193 to prevent color mixing between the red, green, and blue color filters is provided. may be included.

The touch array unit 195 may be formed in a pattern on the color filter 191. The touch array unit 195 includes a transparent channel electrode (not shown) of a cross-shaped shape and a touch pad (not shown) that transmits signals to the transparent channel electrodes, respectively. The touch pad includes a pad electrode (not shown) and can be connected.

As such, the flexible display device according to the first example of the present invention arranges the edge flattening film (EFF) in the non-display area (NDA), thereby dividing the display area (DA) and the non-display area (NDA) of the first substrate 110 ) to reduce the thickness difference. In addition, the flexible display device according to the first example of the present invention arranges the resin layer 180 to be thin so that the cell gap between the first substrate 110 and the second substrate 190 is low, and accordingly, the pixel It is possible to secure a viewing angle, making it possible to implement a high-resolution flexible display device. In addition, the flexible display device according to the first example of the present invention distributes the resin layer 180 thinly and evenly between the planarized first substrate 110 and the second substrate 190, thereby forming a non-bonded area that is not bonded. prevent occurrence. Therefore, the flexible display device according to the first example of the present invention can prevent cracks and peeling of the wiring that may occur during post-processing due to the non-bonding area, and thus, the flexible display device Reliability can be prevented from deteriorating.

FIG. 4 is a cross-sectional view of a flexible display device according to a second example of the present invention, and is a diagram schematically showing the cross-section taken along line II' shown in FIG. 2. This is achieved by changing the first organic layer and the inorganic encapsulation layer and adding a second organic layer in the non-display area of the flexible display device according to the first example shown in FIG. 3. Accordingly, in the following description, only the first organic layer, the inorganic encapsulation layer, and the second organic layer will be described, and duplicate descriptions of the same components will be omitted.

Referring to FIG. 4, the flexible display device according to the second example of the present invention includes a first organic layer 125, an inorganic encapsulation layer 135, and a second organic layer in the non-display area (NDA) of the first substrate 110. It includes a film 145, a first inorganic film 150, and a second inorganic film 170.

The first organic layer 125 is provided in the non-display area NDA on the first substrate 110. The first organic layer 125 is disposed to have a constant height from the first substrate 110 . The first organic layer 125 consists of a plurality of layers and is arranged to be spaced apart from each other at a predetermined interval. In the drawing, the first organic layer 125 is shown in a rectangular shape, but the present invention is not limited thereto. Additionally, the first organic layer 125 may be made of the same material as the planarization layer 120 through the same process, but is not limited thereto.

Unlike the first organic layer 125 according to the first example, the first organic layer 125 according to the second example of the present invention is provided by separating a plurality of first organic layers 125, thereby forming one Even if moisture penetrates the first organic layer 125, it does not affect other first organic layers 125. Accordingly, the flexible display device according to the second example of the present invention can more effectively prevent moisture from penetrating into the display panel 100 from the outside by disposing a plurality of first organic layers 125.

The inorganic encapsulation film 135 is provided between the first organic film 125 and the second organic film 145, and more specifically, is provided to surround the plurality of first organic films 125. Since the inorganic encapsulation film 135 seals the first organic film 125, moisture can be prevented from penetrating into the first organic film 125, which is vulnerable to moisture permeation. In addition, the inorganic encapsulation film 135 according to the second example of the present invention is provided to surround each of the separately provided first organic films 125, so that even if moisture penetrates into one first organic film 125, It can be prevented from affecting the remaining first organic layers 125. The inorganic encapsulation film 135 may be made of the same material and through the same process as the first electrode 130, but is not limited thereto.

The second organic layer 145 is provided between the first organic layers 125 to fill the space between the first organic layers 125 . The second organic layer 145 is provided lower than the height of the first organic layer 125 to prevent a moisture permeation path from being formed. The second organic layer 145 is disposed between the plurality of first organic layers 125 to planarize the non-display area NDA on the first substrate 110. The second organic layer 145 may be made of the same material as the bank 140 through the same process, but is not limited thereto.

As such, the flexible display device according to the second example of the present invention arranges the edge flattening film (EFF) in the non-display area (NDA), thereby dividing the display area (DA) and the non-display area (NDA) of the first substrate 110 ) to reduce the thickness difference. In addition, the flexible display device according to the second example of the present invention arranges the resin layer 180 to be thin to configure a low cell gap between the first substrate 110 and the second substrate 190, and accordingly, the pixel It is possible to secure a viewing angle, making it possible to implement a high-resolution flexible display device. In addition, the flexible display device according to the second example of the present invention distributes the resin layer 180 thinly and evenly between the planarized first substrate 110 and the second substrate 190, thereby forming a non-bonding area in which the resin layer 180 is not bonded. prevent occurrence. Therefore, the flexible display device according to the second example of the present invention can prevent cracks and peeling of the wiring that may occur during post-processing due to the non-bonded area, and thus, the flexible display device Reliability can be prevented from deteriorating.

Additionally, the flexible display device according to the second example of the present invention can more effectively prevent moisture from penetrating into the display panel 100 from the outside by disposing a plurality of first organic layers 125.

5A to 5G are cross-sectional views taken along line I-I to illustrate a method of manufacturing a flexible display device according to an example of the present invention. Accordingly, the same reference numerals are assigned to the same components, and redundant descriptions of repeated parts in the materials and structures of each component are omitted.

First, as shown in FIG. 5A, a thin film transistor (T) is formed in the display area (DA) of the first substrate 110, and a passivation layer (PAS) is formed on the thin film transistor (T), A planarization layer 120 is formed on the passivation layer (PAS). A first organic layer 125 is formed in the non-display area NDA of the first substrate 110. The planarization layer 120 and the first organic layer 125 may be formed of the same material through the same process, but are not limited thereto.

The process of forming the thin film transistor (T) includes forming an active layer (ACT) on the first substrate 110, forming a gate insulating film (GI) on the active layer (ACT), and forming a gate insulating film (GI) on the gate insulating film (GI). A gate electrode (GE) is formed, an interlayer insulating film (ILD) is formed on the gate electrode (GE), and first and second contact holes (CNT1, CNT2) are formed in the interlayer insulating film (ILD) and the gate insulating film (GI). It includes a process of forming the source and drain electrodes (SE, DE) on the interlayer insulating layer (ILD) to be connected to the active layer (ACT) through the first and second contact holes (CNT1, CNT2).

The forming process of the thin film transistor T may use various methods known in the art.

Second, as shown in FIG. 5B, after forming the planarization layer 120 and the first organic layer 125, the passivation layer (PAS) and the drain electrode (DE) of the thin film transistor (T) are exposed. A process of forming a third contact hole (CNT3) is performed in the planarization layer 120, and the first electrode 130 is formed to be electrically connected to the drain electrode (DE) through the third contact hole (CNT3). The first electrode 130 is formed only on the planarization layer 120. An inorganic encapsulation film 135 is formed in the non-display area NDA to surround the first organic film 125. The first electrode 130 and the inorganic encapsulation film 135 may be formed of the same material through the same process, but are not limited thereto. The first electrode 130 and the inorganic encapsulation film 135 may be formed through a deposition process such as sputtering.

Third, as shown in FIG. 5C, after forming the first electrode 130 and the inorganic encapsulation layer 135, the bank 140 is formed on the planarization layer 120. The bank 140 may be formed to overlap the first electrode 130. A second organic layer 145 is formed between the first organic layer 125 in the non-display area NDA. The second organic layer 145 is formed to have a lower height than the first organic layer 125 . The bank 140 and the second organic layer 145 may be formed of the same material through the same process, but are not limited to this. The bank 140 and the second organic layer 145 are formed by applying an organic material to the first electrode 130 using a spin coating method or a slit coating method and then exposing it to a photo process. You can.

Fourth, as shown in FIG. 5D, an organic light emitting layer (EL), a second electrode (CAT), and a first inorganic layer 150 are formed on the first electrode 130. The organic light emitting layer (EL) may be formed through a deposition process or a solution process. When the organic light emitting layer (EL) is formed through a deposition process, it may be formed using an evaporation method. The first inorganic layer 150 is formed entirely on the display panel 100.

Fifth, as shown in FIG. 5E, an organic encapsulation film 160 is formed on the first inorganic film 150 in the display area DA. The organic encapsulation film 160 is formed to be as equal as possible to the height of the non-display area NDA.

Sixth, as shown in FIG. 5F, the second inorganic layer 170 is formed entirely on the display panel 100.

Seventh, as shown in FIG. 5G, a resin layer 180 is formed between the second substrate 190 and the first substrate 110 on which the color filter 191 and the touch array unit 195 are formed, The first substrate 110 and the second substrate 190 are bonded.

As such, the flexible display device according to an example of the present invention arranges the edge flattening film (EFF) in the non-display area (NDA), so that the display area (DA) and the non-display area (NDA) of the first substrate 110 Reduces the thickness difference. In addition, the flexible display device according to an example of the present invention arranges the resin layer 180 to be thin so that the cell gap between the first substrate 110 and the second substrate 190 is low, and accordingly, the viewing angle of the pixel is reduced. It is possible to secure a high-resolution flexible display device. In addition, the flexible display device according to an example of the present invention distributes the resin layer 180 thinly and evenly between the planarized first substrate 110 and the second substrate 190, thereby preventing the generation of non-bonded areas that do not adhere. prevent. Therefore, the flexible display device according to an example of the present invention can prevent cracks and peeling of the wiring that may occur during post-processing due to the non-bonding area, thereby improving the reliability of the flexible display device. This deterioration can be prevented.

Additionally, the flexible display device according to an example of the present invention can more effectively prevent moisture from penetrating into the display panel 100 from the outside by disposing a plurality of first organic layers 125.

Additionally, the method of manufacturing a flexible display device according to an example of the present invention can flatten the display area (DA) and the non-display area (NDA) of the first substrate 110 using an existing process without adding an additional process.

Meanwhile, the method of manufacturing a flexible display device according to an example of the present invention can be applied to both the flexible display devices according to the first and second examples of the present invention when applied by changing the number of first organic layers 125. You can.

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

110: first substrate 120: planarization layer
125: first organic layer 130: first electrode
135: Weapon Encapsulation 140: Bank
145: second organic layer 150: first inorganic layer
160: Organic encapsulation film 170: Second inorganic film
180: Resin layer 190: Second substrate

Claims (13)

It has a display panel divided into a display area where pixels are arranged and a non-display area provided outside the display area,
The display panel is,
first substrate;
a thin film transistor layer including a thin film transistor provided in the display area on the first substrate;
An organic light emitting device layer provided on the thin film transistor layer;
An organic encapsulation film provided on the organic light emitting device layer; and
and an edge planarization film provided in the non-display area on the first substrate,
The height of the edge planarization film is higher than the height of the organic light emitting device layer,
The edge flattening film is,
a plurality of first organic layers having a constant height from the first substrate and being spaced apart from each other at predetermined intervals in a direction perpendicular to the height;
a plurality of second organic films disposed between the plurality of first organic films to fill the space between the plurality of first organic films; and
A flexible display device comprising an inorganic encapsulation film disposed between the plurality of first organic films and the plurality of second organic films to surround each of the plurality of first organic films. delete According to claim 1,
The display panel further includes a planarization layer disposed between the thin film transistor layer and the organic light emitting device layer to planarize an upper portion of the thin film transistor layer,
The first organic layer is a flexible display device made of the same material as the planarization layer. delete According to claim 3,
The organic light emitting device layer is,
a first electrode connected to the source electrode or drain electrode of the thin film transistor;
an organic light-emitting layer disposed on the first electrode; and
It includes a second electrode disposed on the organic light-emitting layer,
A flexible display device wherein the inorganic encapsulation film and the first electrode are made of the same material. According to claim 5,
Further comprising a bank disposed on the planarization layer to partition the first electrode,
A flexible display device wherein the second organic layer is made of the same material as the bank. According to claim 6,
A flexible display device wherein the height of the second organic layer is lower than the height of the first organic layer. According to claim 1,
a first inorganic layer disposed between the organic light emitting device layer and the organic encapsulation layer and covering the edge planarization layer; and
The flexible display device further includes a second inorganic layer covering the organic encapsulation layer in the display area and the first inorganic layer in the non-display area. It includes forming a display panel divided into a display area where pixels are arranged and a non-display area provided outside the display area,
The step of forming the display panel is,
forming a first substrate;
forming a thin film transistor layer including a thin film transistor provided in the display area on the first substrate;
forming an organic light emitting device layer provided on the thin film transistor layer and including a first electrode, an organic light emitting layer, and a second electrode;
forming an organic encapsulation film on the organic light emitting device layer; and
and forming an edge planarization film provided in the non-display area on the first substrate,
The height of the edge planarization film is higher than the height of the organic light emitting device layer,
The step of forming the edge planarization film is,
forming a plurality of first organic layers having a constant height from the first substrate and being spaced apart at predetermined intervals in a direction perpendicular to the height;
forming a plurality of second organic layers disposed between the plurality of first organic layers to fill the space between the plurality of first organic layers; and
A method of manufacturing a flexible display device comprising forming an inorganic encapsulation film between the plurality of first organic layers and the plurality of second organic layers. According to clause 9,
A method of manufacturing a flexible display device in which the height of the second organic layer is lower than the height of the first organic layer. According to claim 10,
After forming the thin film transistor layer, it further includes forming a planarization layer to planarize the upper part of the thin film transistor layer,
A method of manufacturing a flexible display device, wherein the first organic layer is formed through the same process as the planarization layer. According to claim 10,
A method of manufacturing a flexible display device, wherein the inorganic encapsulation film is formed through the same process as the first electrode. According to claim 11,
After forming the first electrode, it further includes forming a bank dividing the first electrode on the planarization layer,
A method of manufacturing a flexible display device, wherein the second organic layer is formed through the same process as the bank.

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