KR102448361B1 - Flexible display device, and method for fabricating the same - Google Patents

Abstract

The present invention provides a flexible display device capable of preventing damage to the surface of a base film or damage to a thin film transistor by a laser, which is generated in the process of separating a base film and an auxiliary substrate, and a method of manufacturing the same. A flexible display device according to an embodiment of the present invention provides a non-display device including a base film, a display area including thin film transistors disposed on a first surface of the base film, and pads disposed on at least one side of the display area. A region is provided, and an intaglio pattern is provided on a second surface opposite to the first surface of the base film.

Description

Flexible display device and manufacturing method thereof

Embodiments of the present invention relate to a flexible display device and a method of manufacturing the same.

As the era develops into an information society, the importance of flat panel display devices (FPDs) having excellent characteristics such as thinness, light weight, and low power consumption is increasing. Flat panel displays include a liquid crystal display device (LCD), a plasma display panel device (PDP), an organic light emitting display device (OLED), and the like, and recently electrophoresis. An electrophoretic display device (EPD) is also widely used.

Among them, liquid crystal display devices and organic light emitting display devices including thin film transistors have excellent resolution, color display, and image quality, and are widely commercialized as display devices for televisions, notebook computers, tablet computers, or desktop computers. Such a liquid crystal display device and an organic light emitting display device are being developed as a flexible display device having flexibility.

A conventional flexible display panel includes a base film, a buffer layer, a thin film transistor, and an organic light emitting diode. The base film is provided on the auxiliary substrate and may be a flexible plastic film. The buffer layer is provided on the base film, and the thin film transistor is provided on the buffer layer. The organic light emitting diode is provided on the thin film transistor and is electrically connected to the thin film transistor. Such a conventional flexible display panel may be manufactured by sequentially forming a base film, a buffer layer, a thin film transistor, and an organic light emitting diode on an auxiliary substrate, and then separating the base film and the auxiliary substrate using a laser.

However, in the conventional flexible display device, the surface of the base film may be damaged in the process of separating the base film and the auxiliary substrate, or the thin film transistor may be damaged by the laser. Accordingly, the reliability of the flexible display panel may be deteriorated.

The present invention provides a flexible display device capable of preventing damage to the surface of a base film or damage to a thin film transistor by a laser, which is generated in the process of separating a base film and an auxiliary substrate, and a method of manufacturing the same.

A flexible display device according to an embodiment of the present invention provides a non-display device including a base film, a display area including thin film transistors disposed on a first surface of the base film, and pads disposed on at least one side of the display area. A region is provided, and an intaglio pattern is provided on a second surface opposite to the first surface of the base film.

A method of manufacturing a flexible display device according to an embodiment of the present invention includes: patterning a sacrificial layer on an auxiliary substrate; forming a base film to cover the sacrificial layer on the auxiliary substrate; forming thin film transistors and pads thereon, and separating the auxiliary substrate and the base film by using a laser to form an intaglio pattern on a second surface of the base film opposite to the first surface of the base film.

In an embodiment of the present invention, the intaglio pattern is provided on the second surface opposite to the first surface of the base film on which the thin film transistor is provided. Such an intaglio pattern may be provided by a sacrificial layer patterned on the auxiliary substrate in the process of forming the base film. Since the embodiment of the present invention is provided with the intaglio pattern, it is possible to prevent damage to the surface of the base film or damage to the thin film transistor by the laser, which is generated in the process of separating the base film from the auxiliary substrate.

In addition to the effects of the present invention mentioned above, other features and advantages of the present invention will be described below or will be clearly understood by those skilled in the art from such description and description.

1 is a perspective view showing a flexible display device according to an embodiment of the present invention;
FIG. 2 is a plan view illustrating a display area and a non-display area, a gate driver, a source drive IC, a flexible film, a circuit board, and a timing controller of the first substrate of FIG. 1 ;
3 is a plan view illustrating pixels of a display area according to an embodiment of the present invention;
FIG. 4 is a cross-sectional view showing an example of line I-I' of FIG. 2;
5 is a cross-sectional view showing an example of II-II' of FIG. 3;
6 is a flowchart illustrating a method of manufacturing a flexible display device according to an embodiment of the present invention.
7A to 7F are cross-sectional views illustrating a method of manufacturing a flexible display device according to an embodiment of the present invention;

The meaning of the terms described herein should be understood as follows.

The singular expression is to be understood as including the plural expression unless the context clearly defines otherwise, and the terms "first", "second", etc. are used to distinguish one element from another, The scope of rights should not be limited by these terms. It should be understood that terms such as “comprise” or “have” do not preclude the possibility of addition or existence of one or more other features or 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, the meaning of "at least one of the first, second, and third items" means 2 of the first, second, and third items as well as each of the first, second, or third items. It means a combination of all items that can be presented from more than one. The term “on” is meant to include not only cases in which a certain component is formed directly on top of another component, but also a case in which a third component is interposed between these components.

Hereinafter, a preferred example of a flexible display device and a method for manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to components of each drawing, the same components may have the same reference numerals as much as possible even though they are indicated in different drawings. In addition, in describing the present invention, when 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.

1 is a perspective view illustrating a flexible display device according to an exemplary embodiment of the present invention. FIG. 2 is a plan view illustrating a display area and a non-display area, a gate driver, a source drive IC, a flexible film, a circuit board, and a timing controller of the first substrate of FIG. 1 . 3 is a plan view illustrating pixels of a display area according to an exemplary embodiment of the present invention.

In FIG. 1 , the X axis indicates a direction parallel to the gate line, the Y axis indicates a direction parallel to the data line, and the Z axis indicates a height direction of the flexible display device. Configurations that are not visible in the perspective view of FIG. 1 and the plan view of FIG. 2 are indicated by dotted lines. Hereinafter, a flexible display device according to an exemplary embodiment of the present invention will be described with reference to FIGS. 1 to 3 .

1 to 3 , a flexible display device according to an embodiment of the present invention includes a flexible 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 controller 400 .

The flexible display panel 100 includes a display area DA and a non-display area NDA. Gate lines, data lines, and pixels are formed in the display area DA of the flexible display panel 100 . The pixels P of the display area NA include a plurality of light-emitting areas RE, GE, and BE, and the light-emitting areas RE, GE, and BE are formed at intersections of gate lines and data lines. do. The display area DA displays an image by means of the pixels P. In the present invention, although it is exemplified that each of the pixels P includes a red emission region RE, a green emission region GE, and a blue emission region BE, the present invention is not limited thereto. That is, each of the pixels P may further include a white emission region as well as a red emission region RE, a green emission region GE, and a blue emission region BE. A bank is disposed between the light emitting regions RE, GE, and BE. The light emitting regions RE, GE, and BE are partitioned by banks. The non-display area NDA is disposed at the edge of the display area DA. The gate driver 200 and pads may be provided in the non-display area NDA.

The flexible display panel 100 includes a protective film 120 , a base film 110 , and an upper film 190 . The protective film 120 may be attached to the second surface of the base film 110 to protect and support the base film 110 . The base film 110 may be a flexible plastic film such as polyimide. The upper film 190 may be a protection film when the display panel 110 is implemented in a bottom emission method, and may be formed of polyimide and polyimide when the display panel 110 is implemented in a top emission method. The same may be a flexible plastic film.

The gate driver 200 supplies gate signals to the gate lines according to a gate control signal input from the timing controller 400 . 1 illustrates that the gate driver 200 is formed on one side of the outer side of the display area DA of the flexible display panel 100 by a gate driver in panel (GIP) method, but is not limited thereto. That is, the gate driver 200 may be formed in a GIP method on both sides of the display area DA of the flexible display panel 100 , or manufactured as a driving chip, mounted on a flexible film, and performed by tape automated bonding (TAB). In this way, it may be attached to the flexible display panel 100 .

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

The upper film 190 may be provided to be smaller than the base film 110 . Accordingly, a portion of the base film 110 may be exposed without being covered by the upper film 190 . Pads such as data pads are provided on a portion of the base film 110 that is not covered by the upper film 190 and is exposed. 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 on the flexible film 330 . The flexible film 330 is attached on the pads using an anisotropic conducting film, whereby the pads and the wirings of the flexible film 330 can be connected.

The circuit board 350 may be attached to the flexible films 330 . A plurality of circuits implemented with driving chips may be mounted on the circuit board 350 . For example, the timing controller 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 controller 400 receives digital video data and a timing signal from an external system board (not shown). The timing controller 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 driver ICs 310 based on the timing signal. The timing controller 400 supplies the gate control signal to the gate driver 200 and supplies the source control signal to the source drive ICs 310 .

Although the flexible display device according to the embodiment of the present invention has been mainly described as being implemented as an organic light emitting display, it may be implemented as a liquid crystal display or an electrophoresis display. may be

4 is a cross-sectional view illustrating an example of line I-I' of FIG. 2 . 5 is a cross-sectional view illustrating an example of II-II′ of FIG. 3 . 4 is a cross-sectional view illustrating a cross section of the display area DA and the non-display area NDA shown in FIG. 2 . FIG. 5 is a cross-sectional view illustrating a cross section of the light emitting areas RE and GE and the non-emission area NEA of the display area DA shown in FIG. 3 .

4 and 5 , the flexible display panel 100 includes a display area DA and a non-display area NDA. The display area DA of the flexible display panel 100 includes light-emitting areas RE and GE and a non-emission area NEA. Organic light emitting devices OLED and color filters RC and GC may be provided in the light emitting regions RE and GE. Banks 170 partitioning the thin film transistors T and the light emitting regions RE and GE may be provided in the non-emission area NEA. The non-display area NDA is disposed at the edge of the display area DA. Pads 160 may be provided in the non-display area NDA.

Specifically, the flexible display panel 100 includes a protective film 120 , a base film 110 , a buffer layer 130 , a thin film transistor T, a passivation layer PAS, a planarization layer PAC, and an organic light emitting device (OLED). , an encapsulation layer 180 , and an upper film 190 .

The protective film 120 is attached to the second surface 110b of the base film 110 . The protective film 120 protects and supports the base film 110 . For example, the protective film 120 may be a polyethylene terephthalate (PET) film or a poly carbonate (PC) film, but is not limited thereto.

The base film 110 is provided on the protective film 120 . A thin film transistor T and pads 160 are provided on the first surface 110a of the base film 110 . Intaglio patterns 112 are provided on the second surface 110b of the base film 110 opposite to the first surface 110a. Although one engraved pattern 112 is illustrated in the drawing, at least one engraved pattern 112 may be provided on the entire second surface 110b of the base film 110 corresponding to the non-display area NDA. . The intaglio patterns 112 are provided to be concave from the second surface 110b of the base film 110 in the upper direction (Z-axis direction) in which the pads 160 are provided. The engraved patterns 112 are disposed at positions corresponding to the non-display area NDA. Accordingly, the thickness of the base film 110 in the non-display area NDA is smaller than the thickness of the base film 110 in the display area DA. The engraved patterns 112 are disposed at positions corresponding to the non-emission area NEA in the display area NA. The engraved patterns 112 are disposed at positions corresponding to the thin film transistor (T). Accordingly, the thickness of the base film 110 in the non-emission area NEA is smaller than the thickness of the base film 110 in the light emission areas RE and GE.

The base film 110 may be a flexible plastic film. For example, the base film 110 is a cellulose resin such as triacetyl cellulose (TAC) or diacetyl cellulose (DAC), a cyclo olefin polymer (COP) such as norbornene derivatives, a cyclo olefin copolymer (COC), Acrylic resin such as PMMA(poly(methylmethacrylate), PC(polycarbonate), PE(polyethylene) or PP(polypropylene), polyolefin(polyolefin), PVA(polyvinyl alcohol), PES(poly ether sulfone), PEEK(polyetheretherketone), Polyetherimide (PEI), polyethylenenaphthalate (PEN), or polyester such as polyethyleneterephthalate (PET), polyimide (PI), polysulfone (PSF), or fluoride resin may be a sheet or film containing, The base film 110 will be described in detail later with reference to the manufacturing method of FIGS. 6 and 7A to 7F .

Additionally, an adhesive member 125 is provided between the base film 110 and the protective film 120 . The adhesive member 125 is provided between the second surface 110b of the base film 110 and the protective film 120 to adhere the base film 110 and the protective film 120 . The adhesive member 125 is filled between the intaglio patterns 122 and the protective film 120 to adhere the base film 110 and the protective film 120 . For example, the adhesive member 125 may be a transparent adhesive film such as an optically clear adhesive (OCA) or a transparent adhesive such as an optically clear resin (OCR), but is not limited thereto.

The buffer layer 130 is provided on the first surface 110a of the base film 110 . The buffer layer 130 prevents moisture from penetrating into the flexible display panel 100 from the base film 110 which is vulnerable to moisture permeation and degrading the characteristics of the thin film transistors T. In addition, the buffer layer 130 prevents impurities such as metal ions from diffusing from the base film 110 and penetrating into the active layer ACT. To this end, the buffer layer 130 may include at least one inorganic layer. The buffer layer 130 may be, for example, silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or a multilayer thereof, but is not limited thereto.

The thin film transistor T is provided on the first surface 110a of the base film 110 . The thin film transistor T is provided in the display area DA of the base film 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 active layer ACT is provided on the buffer layer 130 . The active layer ACT has one end region A1 positioned on the source electrode SE side, the other end region A2 positioned on the drain electrode DE side, and a center positioned between the one end region A1 and the other end region A2. It may include an area A3. The central region A3 may be made of a semiconductor material undoped with a dopant, and the one end region A1 and the other end region A2 may be made of a semiconductor material doped with a dopant.

The gate insulating layer GI is provided on the active layer ACT. The gate insulating layer GI functions to insulate the active layer ACT from the gate electrode GE. The gate insulating layer GI covers the active layer ACT and is formed on the entire surface of the display area DA. The gate insulating layer GI may be formed of an inorganic layer, for example, silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or a multilayer thereof, but is not limited thereto.

The gate electrode GE is provided on the gate insulating layer GI. The gate electrode GE overlaps the central region A3 of the active layer ACT with the gate insulating layer GI interposed therebetween. The gate electrode GE may include, 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 multiple layers made of any one or an alloy thereof, but is not limited thereto.

The interlayer insulating layer ILD is provided on the gate electrode GE. The interlayer insulating layer ILD covers the gate electrode GE and may be provided on the entire surface of the base film 110 . The interlayer insulating layer ILD may be formed of the same inorganic layer as the gate insulating layer GI, for example, silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or a multilayer thereof, but is not limited thereto. does not

The source electrode SE and the drain electrode DE are disposed to be spaced apart from each other on the interlayer insulating layer ILD. A portion of the first contact hole CNT1 exposing a portion of the region A1 at one end of the active layer ACT and a portion of the region A2 at the other end of the active layer ACT are formed in the gate insulating layer GI and the interlayer insulating layer ILD. A second contact hole CNT2 to be exposed 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 . is connected to the other end area A2 of the For example, the source electrode SE and the drain electrode DE may include molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), or neodymium (Nd). and copper (Cu), or may be a single layer or a multilayer made of an alloy thereof, but is not limited thereto.

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

When the source electrode SE and the drain electrode DE are provided in the display area NA, pads 160 may be provided in the non-display area NDA. The pads 160 may be made of the same material as the source electrode SE and the drain electrode DE. A flexible film 330 electrically connected to the circuit board 350 and mounted with the source drive IC 310 may be attached to the pads 160 .

The passivation layer PAS is provided on the thin film transistor T. The passivation layer PAS serves to protect the thin film transistor T. The passivation layer PAS may be formed of an inorganic layer, for example, silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiON), or a multilayer thereof, but is not limited thereto.

The color filters RC and GC are provided on the passivation layer PAS. The color filters RC and GC are provided in the light emitting regions RE and GE on the base substrate 110 so as not to overlap the thin film transistor T. Referring to FIG. The color filters RC and GC are used to implement color in the flexible display panel 100 . For example, light emitted from the organic light emitting diode OLED passes through the color filters RC and GC and is emitted downward. In the drawings of the present invention, only the red color filter RC disposed in the red emission region RE and the green color filter GC disposed in the green emission region GE are illustrated, but the present invention is not limited thereto. That is, the flexible display panel 100 may further include a blue color filter disposed in the blue light emitting area and a white color filter disposed in the white light emitting area.

The planarization layer PAC is provided on the passivation layer PAS. The planarization layer PAC covers the thin film transistor T and the color filters RC and GC. The planarization layer PAC serves to flatten the upper portion of the base substrate 110 on which the thin film transistor T and the color filters RC and GC are provided. For example, it may be made of acrylic resin, epoxy resin, phenolic resin, polyamides resin, polyimides resin, etc., but is not limited thereto. A third contact hole CNT3 exposing the drain electrode DE of the thin film transistor T is provided in the planarization layer PAC and the passivation layer PAS. (DE) and the anode electrode (AND) are connected.

The organic light emitting diode (OLED) is connected to the thin film transistor (T). The organic light emitting diode OLED is provided on the thin film transistor T and the color filters RC and GC. The organic light emitting device OLED includes an anode electrode AND, an organic light emitting layer EL, and a cathode electrode CAT.

The anode electrode AND 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 PAC. The anode electrode AND may be a transparent conductive material having a relatively large work function value, for example, indium-tin-oxide (ITO) or indium-zinc-oxide (IZO). In addition, the anode electrode AND may be formed of at least two or more layers including a metal material having excellent reflection efficiency, for example, aluminum (Al), silver (Ag), APC (Ag; Pb; Cu), or the like.

The bank 170 is provided between the anode electrodes AND adjacent to each other. The bank 170 electrically insulates the anode electrodes AND adjacent to each other. The bank 170 covers one side of the anode electrode AND. The bank 170 is disposed in the non-emission area NEA of the display area DA. The bank 170 is disposed to correspond to the engraved pattern 112 provided on the second surface 110b of the base film 110 . The bank 170 according to an embodiment of the present invention may be a black bank including a light absorbing material. For example, the bank 170 may include an organic film including a black pigment such as carbon black, for example, polyimides resin, acryl resin, benzocyclobutene (BCB), or the like. It may be formed of the same organic layer, but is not limited thereto.

When a conventional bank that does not include a light absorbing material is applied, external light incident into the display panel from the outside is reflected by the cathode electrode CAT and emitted to the outside of the display panel, so that the outdoor visibility of the display panel is deteriorated. Problems may arise. However, when the bank 170 including the light absorbing material is applied, since both external light incident from the outside and reflected light reflected by the cathode electrode CAT are absorbed, the outdoor visibility of the display panel may be improved. .

The organic light emitting layer EL is provided on the anode electrode AND. 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 for improving luminous efficiency and/or lifespan of the light emitting layer.

The cathode electrode CAT is provided on the organic light emitting layer EL and the bank 170 . When a voltage is applied to the anode electrode AND and the cathode electrode CAT, holes and electrons move to the organic light emitting layer EL through the hole transport layer and the electron transport layer, respectively, and combine with each other in the organic light emitting layer EL to emit light.

The encapsulation layer 180 is provided on the thin film transistor T and the organic light emitting diode OLED. The encapsulation layer 180 covers the thin film transistor T and the organic light emitting diode OLED. The encapsulation layer 180 serves to protect the thin film transistor T and the organic light emitting diode OLED from external impact, and to prevent moisture from penetrating into the flexible display panel 100 .

The upper film 190 is provided on the encapsulation layer 180 . The upper film 190 may be a protection film when the flexible display panel 100 is implemented in a bottom emission method, and may be formed of polyimide when the flexible display panel 100 is implemented in a top emission method. It may be a flexible plastic film, such as However, the present invention is not limited thereto, and the upper film 190 may be a metal layer for protecting the thin film transistor T and the organic light emitting diode OLED from external impact and preventing moisture from penetrating.

In the embodiment of the present invention, the intaglio patterns 112 are provided on the second surface 110b opposite to the first surface 110a of the base film 110 on which the thin film transistor T is provided. These engraved patterns 112 may be provided by a sacrificial layer patterned on the auxiliary substrate in the process of forming the base film 110 . In the embodiment of the present invention, since the engraved patterns 112 provided on the second surface 110b of the base film 110 are disposed to correspond to the non-display area NDA, the base film 110 is separated from the auxiliary substrate. It is possible to prevent damage to the surface of the base film 110 generated in the process.

In the embodiment of the present invention, since the engraved patterns 112 provided on the second surface 110b of the base film 110 are disposed to correspond to the non-emission area NEA, the base film 110 is separated from the auxiliary substrate. It is possible to prevent damage to the thin film transistor T by the laser generated in the process. In addition, since the intaglio patterns 112 are not provided in the light emitting regions RE and GE, the optical properties such as transmittance and color coordinates of the light emitting regions RE and GE due to the remaining sacrificial layer material are prevented from being deteriorated. can

6 is a flowchart illustrating a method of manufacturing a flexible display device according to an embodiment of the present invention. 7A to 7F are cross-sectional views illustrating a method of manufacturing a flexible display device according to an exemplary embodiment of the present invention. This relates to a method of manufacturing a flexible display device according to an embodiment of the present invention shown in FIG. 4 . Accordingly, the same reference numerals are assigned to the same components, and repeated descriptions of parts that are repeated in the materials and structures of each component will be omitted.

First, as shown in FIG. 7A , the sacrificial layer 107 is patterned on the auxiliary substrate 105 . The sacrificial layer 107 may be patterned at positions corresponding to the non-display area NDA and the non-emission area NDA of the display panel. For example, the sacrificial layer 107 may be amorphous silicon. When a laser is irradiated to the sacrificial layer 107 in a process of separating the auxiliary substrate 105 and the base film 110 later, amorphous silicon may be crystallized. Accordingly, the base film 110 and the auxiliary substrate 105 may be separated from each other without damaging the surface of the base film 110 . An inorganic layer for improving adhesion between the auxiliary substrate 105 and the sacrificial layer 107 may be additionally provided between the auxiliary substrate 105 and the sacrificial layer 107 . For example, the inorganic layer may be silicon nitride (SiNx), but is not limited thereto. (S101 in FIG. 6)

Second, the base film 110 is formed to cover the sacrificial layer 107 on the auxiliary substrate 105 as shown in FIG. 7B . For example, the base film 110 may be formed by a slit coating method. The slit coating method is a method of forming a thin flexible film by uniformly coating a liquid material used as the base film 110 on the auxiliary substrate 105 using a nozzle and then curing it. However, the present invention is not limited thereto, and the base film 110 may be formed by a roll coating method or a spin coating method. (S102 in FIG. 6)

Third, thin film transistors T and pads 160 are formed on the first surface 110a of the base film 110 as shown in FIG. 7C . In this case, the thin film transistors T are disposed in the non-emission area NEA of the display panel, and the pads 160 are disposed in the non-display area NDA. First, a buffer layer 130 , an active layer ACT, and a gate insulating layer G1 are sequentially formed on the base film 110 . Next, the gate electrode GE is formed to overlap the active layer ACT on the gate insulating layer GI disposed in the display area DA. Next, an interlayer insulating layer ILD is formed on the gate electrode GE. Finally, the source electrode SE and the drain electrode DE connected to the active layer ACT through the first and second contact holes CNT1 and CNT2 are formed on the interlayer insulating layer ILD, and the non-display Pads 160 are formed in the area NDA. In this case, the source electrode SE, the drain electrode DE, and the pads 160 are simultaneously formed through the same process and may be made of the same material. (S103 in FIG. 6)

Fourth, as shown in FIG. 7D , the organic light emitting diodes (OLEDs) connected to the thin film transistors (T) are formed, and the encapsulation layer 180 covering the organic light emitting elements (OLEDs) is formed. A passivation layer PAS and a planarization layer PAC are sequentially formed on the thin film transistors T. The anode electrode AND is formed on the thin film transistor T and is connected to the drain electrode DE through the third contact hole CNT3 provided in the passivation layer PAS and the planarization layer PAC. A bank B is formed between the anode electrodes AND adjacent to each other. The organic layer EL is formed on the anode electrode AND. The cathode electrode CAT is formed on the organic layer EL and the bank B. The encapsulation layer 180 is formed to cover the thin film transistor T and the organic light emitting diode OLED. A front adhesive layer 190 may be additionally formed on the encapsulation layer 180 . Next, a flexible film 330 electrically connected to the circuit board 350 and mounted with the source drive IC 310 is attached on the pads 160 of the non-display area NDA.

Fifth, the base film 110 is separated from FIG. 7E and the auxiliary substrate 115 . The auxiliary substrate 115 and the base film 110 may be separated from each other using a laser. In this case, laser is irradiated to the sacrificial layer 107 to separate the base film 110 and the auxiliary substrate 105 from each other without damaging the surface of the base film 110 . As the auxiliary substrate 105 and the base film 110 are separated, the intaglio patterns 112 are provided on the second surface 110b, which is the opposite surface of the first surface 110a of the base film 110 . (S104 in FIG. 6)

Finally, as shown in FIG. 7F , the protective film 120 is attached to the second surface 110b of the base film 110 using an adhesive member 125 . In this case, the adhesive member 125 is filled between the intaglio patterns 112 and the protective film 120 to adhere the base film 110 and the protective film 120 .

In summary, the flexible display panel 100 is formed by sequentially forming a base film 110 , a thin film transistor T, and an organic light emitting diode OLED on an auxiliary substrate 105 , and then using a laser. It may be manufactured by separating the base film 110 and the auxiliary substrate. In this case, the sacrificial layer 107 is patterned between the auxiliary substrate 105 and the base film 110 . When the sacrificial layer 107 is provided between the auxiliary substrate 105 and the base film 110 , damage to the base film 110 due to a laser release process may be reduced. The sacrificial layer 107 is patterned at a position corresponding to the non-display area NDA. When the base film 110 and the auxiliary substrate 105 are separated, the base film 110 is separated from the auxiliary substrate 105 while the sacrificial layer 107 is crystallized. As the sacrificial layer 107 and the auxiliary substrate 105 are separated, engraved patterns 112 may be provided on the second surface 110b of the base film 110 .

In the embodiment of the present invention, since the engraved patterns 112 provided on the second surface 110b of the base film 110 are disposed to correspond to the non-display area NDA, the base film 110 is separated from the auxiliary substrate. It is possible to prevent damage to the surface of the base film 110 generated in the process.

In the embodiment of the present invention, since the engraved patterns 112 provided on the second surface 110b of the base film 110 are disposed to correspond to the non-emission area NEA, the base film 110 is separated from the auxiliary substrate. It is possible to prevent damage to the thin film transistor T by the laser generated in the process. In addition, since the intaglio patterns 112 are not provided in the light emitting regions RE and GE, the optical properties such as transmittance and color coordinates of the light emitting regions RE and GE due to the remaining sacrificial layer material are prevented from being deteriorated. can

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

100: flexible display panel
105: auxiliary substrate 107: sacrificial layer
111: first base film 113: second base film
130: buffer layer 180: encapsulation layer
190: front adhesive layer 200: gate driver
310: source drive IC 330: flexible film
350: circuit board 400: timing control unit
T: thin film transistor OLED: organic light emitting device
DA: display area NDA: non-display area
RE, GE: Emitting area NEA: Non-emissive area

Claims (11)

base film;
a display area including thin film transistors disposed on a first surface of the base film; and
a non-display area including pads disposed on at least one side of the display area;
An engraved pattern is disposed on a second side opposite to the first side of the base film,
The display area includes a light emitting area including organic light emitting devices disposed on the thin film transistors,
The engraved pattern is not disposed at a position corresponding to the light emitting area. The method of claim 1,
The engraved pattern is disposed at a position corresponding to the non-display area. The method of claim 1,
A thickness of the base film in the non-display area is thinner than a thickness of the base film in the display area. The method of claim 1,
The display area further includes a non-emission area including banks dividing the light-emitting area,
The engraved pattern is disposed at a position corresponding to the non-emission area. 5. The method of claim 4,
A thickness of the base film in the non-emission region is thinner than a thickness of the base film in the emission region. 6. The method according to claim 4 or 5,
The thin film transistor is disposed in the non-emission area. The method of claim 1,
a protective film disposed on the second surface of the base film; and
The flexible display device further comprising an adhesive member for adhering the base film and the protective film. 5. The method of claim 4,
an encapsulation layer provided on the organic light emitting devices and the banks; and
The flexible display device further comprising an upper film provided on the encapsulation layer. patterning a sacrificial layer on the auxiliary substrate;
forming a base film on the auxiliary substrate to cover the sacrificial layer;
forming thin film transistors in a display area on the first surface of the base film and forming pads in a non-display area; and
Separating the auxiliary substrate and the base film using a laser, comprising the step of providing an intaglio pattern on a second surface opposite to the first surface of the base film,
The display area includes a light emitting area including organic light emitting devices connected to each of the thin film transistors,
The method of manufacturing a flexible display device in which the engraved pattern is not disposed at a position corresponding to the light emitting area. 10. The method of claim 9,
The method of manufacturing a flexible display device further comprising the step of forming an encapsulation layer on the organic light emitting devices. 10. The method of claim 9,
and attaching a protective film to the second surface of the base film using an adhesive member.

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