KR102511040B1 - Flexible Display Device and Method for Manufacturing the Same - Google Patents

Abstract

The present invention relates to a flexible display device that is easily peelable when glass is removed, and a method for manufacturing the same. By forming a hole, the inorganic film having a strong binding force to the glass substrate is eliminated from the edge, thereby facilitating separation of the glass substrate.

Description

Flexible display device and manufacturing method thereof {Flexible Display Device and Method for Manufacturing the Same}

The present invention relates to a display device, and more particularly, to a flexible display device that is easily peelable when glass is removed and a method for manufacturing the same.

Specific examples of the flat panel display device include a liquid crystal display device (LCD), an organic light emitting display device (Organic Emitting Display Device), a plasma display panel device (PDP), and a quantum dot display device (Quantum Dot Display Device). ), field emission display device (FED), electrophoretic display device (EPD), etc., which commonly use a flat panel display panel for realizing an image as an essential component, A flat panel display panel has a structure in which a pair of transparent insulating substrates are bonded face-to-face with an inherent light emitting or polarizing or other optical material layer interposed therebetween.

With the recent increase in the size of display devices, demand for a flat display device that occupies less space is increasing. This demand is increasing, and recently, there is a demand for using a flat display device in a flexible form.

A flexible display device considered in response to such a demand has gradually become thinner and has been developed into a foldable type. In addition, in consideration of user's convenience, a form in which a touch screen is added to the upper side has also been proposed.

Among flexible display devices with a touch screen, an example in which a display panel is used as an organic light emitting display panel is drawing attention because it can be configured with a slimmer and lighter weight by omitting a light source, and thus can be easily implemented in a flexible form.

In a typical flexible display device, a thin film transistor array and an organic light emitting diode array are formed on a lower glass substrate, and a touch sensing array is formed on an upper glass substrate, and then the two glass substrates are bonded together with adhesive layers corresponding to each other.

On the other hand, the upper glass substrate and the lower glass substrate are removed in the mentioned order, and laser is irradiated so that the glass substrate is separated from the array adjacent to the glass substrate, thereby removing the upper and lower glass substrates.

However, in the process of removing the upper and lower glass substrates, in addition to laser irradiation, a physical external force is applied to the array side to completely remove the glass substrate. . As a result, there is a problem in which the operation of the cracked array is impossible, and a solution thereof is required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has an object to provide a flexible display device that can be easily peeled when glass is removed, and a method for manufacturing the same.

In order to achieve the above object, the flexible display device of the present invention forms a polymer substrate on a glass substrate, forms inorganic films thereon, and then forms a hole along the edge of the polymer substrate, so that the edge has a strong bonding force to the glass substrate. By eliminating the inorganic films with the, it facilitates the separation of the glass substrate.

To this end, the flexible display device of the present invention includes a first polymer substrate having a lower surface that is wider than an upper surface and having an inclination at the side, a second polymer substrate facing the first polymer substrate, and the first polymer substrate. A multi-layered inorganic film covering an upper surface and a side surface and having a cut surface corresponding to an edge line defined by a lower surface of the first polymer substrate and an adhesive layer provided between the first and second polymer substrates.

In addition, a cut surface of the multi-layered inorganic film may have a rectangular shape along the edge of the lower surface of the first polymer substrate in plan view.

In addition, an inorganic film pattern connected to the plurality of inorganic films may be further included at each corner of the quadrangular edge.

Meanwhile, the cut surfaces of the multi-layered inorganic film may be provided discontinuously along the edge line of the first polymer substrate. In this case, inorganic film patterns protruding outwardly of the first polymer substrate may be further included between cut surfaces of the discontinuously provided inorganic film on a plane.

Meanwhile, the inorganic layer may include a plurality of layers of a buffer layer, an interlayer insulating layer, and a protective layer.

Here, first touch electrodes and second touch electrodes may be further provided on the plurality of buffer layers and vertically positioned with the interlayer insulating film as a boundary. The passivation layer may cover the interlayer insulating layer and the second touch electrode.

In addition, a thin film transistor array and an organic light emitting diode array connected thereto may be further included on the second polymer substrate. The first and second surfaces of the adhesive layer may contact the organic light emitting diode array and the passivation layer, respectively.

The first and second polymer substrates may be polyimide.

Meanwhile, a method of manufacturing a flexible display device of the present invention for achieving the same object includes forming a first polymer substrate on a first glass substrate, covering the first polymer substrate on top of the first polymer substrate, and , Forming an inorganic film that protrudes from the edge of the first polymer substrate by a predetermined width and contacts the first glass substrate, and removes the inorganic film from the edge of the first polymer substrate to expose the first glass substrate. Forming a second polymer substrate on a second glass substrate, bonding between the inorganic film and the second polymer substrate through an adhesive layer, and on the rear surface of the first glass substrate The step of removing the first glass substrate by irradiating a laser beam and the step of removing the second glass substrate by irradiating a laser beam from the rear surface of the second glass substrate are included.

The flexible display device and the manufacturing method of the present invention have the following effects.

On the glass substrate, for the inorganic film protruding from the edge of the polymer substrate, by providing a hole along the edge of the polymer substrate, in the process of removing the glass substrate, the glass substrate is naturally separated from the polymer substrate only by laser irradiation without application of external force. can be peeled off.

Therefore, when removing the glass substrate, external force is not applied to the polymer substrate, which causes cracks on the edge that occurred during the removal of the conventional glass substrate to be transmitted to the active area. Remaining problems can be solved.

In addition, it can be applied to TV, tablet or mobile products as an application, so that mass production and panel reliability of the product can be secured.

1 is a cross-sectional view of a touch screen of the present invention.
2 is a plan view of a touch screen of the present invention;
Figure 3 is a plan view showing the configuration on the first glass substrate in manufacturing the touch screen of the present invention.
4a to 4c are cross-sectional views illustrating a method of manufacturing a touch screen.
5 is a cross-sectional view illustrating an active area and an inactive area of the flexible display device according to the present invention.
6 is a process cross-sectional view illustrating a manufacturing method of the flexible display device according to the present invention.
7 is a plan view of a first glass substrate showing inorganic film holes and inorganic film stacking patterns in the touch screen manufacturing method of the present invention.
8A to 8B are cross-sectional views along lines II to II' and II to II' in FIG. 7;
9a and 9b are plan views of the touch screen showing the inorganic film hole forming step and after removing the first glass substrate in the touch screen manufacturing method according to the first embodiment of the present invention.
10A and 10B are plan views of the touch screen showing the inorganic film hole formation step and after removing the first glass substrate in the touch screen manufacturing method according to the second embodiment of the present invention.
11a and 11b are plan views of the touch screen showing the inorganic film hole forming step and after removing the first glass substrate in the touch screen manufacturing method according to the third embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Like reference numbers throughout the specification indicate substantially the same elements. In the following description, if it is determined that a detailed description of a known technology or configuration related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, the component names used in the following description are selected in consideration of the ease of writing the specification, and may be different from the part names of the actual product.

1 is a cross-sectional view of a touch screen of the present invention, and FIG. 2 is a plan view of the touch screen of the present invention. 3 is a plan view showing the configuration on the first glass substrate when manufacturing the touch screen of the present invention.

1, the touch screen 1000 of the present invention includes a first polymer substrate 110, a first plurality of buffer layers 120 on the first polymer substrate 110, an interlayer insulating film 130, and a protective film 140. ).

And, as shown in FIG. 1, in the touch screen 1000, the upper and lower surfaces of the first polymer substrate 110 are formed in different areas, and in particular, in the outer region, the lower surface corresponds to the upper surface. The first plurality of buffer layers 120, the interlayer insulating film 130, and the protective film 140 are formed on the inclined side surface of the first polymer substrate 110. is covering

Here, the edges of the first plurality of buffer layers 120, the interlayer insulating film 130, and the protective film 140 have a vertical cut surface coincident with the edge line in common.

In a flexible display device, after forming a film from the first polymer substrate 110 on a first glass substrate for flexibility of the device and bending or folding of a specific area, the first polymer substrate An array is formed on (110), and then a process of removing the first glass substrate for softening is performed.

However, in the first polymer substrate 110 of organic polymer components coated by a relatively solution process, the solution gathers and aggregates from the edge line of the first glass substrate 100 to the inside, and has a certain inclination at the edge.

On the other hand, as shown in FIG. 3, the inorganic film laminate 170 including the first plurality of buffer layers 120, the interlayer insulating film 130, and the protective film 140 of inorganic components deposited by the inorganic gas CVD (Chemical Vapor Deposition) method is It is formed protruding from the edge of the first polymer substrate 110 so as to cover the edge of the first polymer substrate 110 .

The first plurality of buffer layers, interlayer insulating film, and protective film components of inorganic components covering the edges and outer edges of the first polymer substrate have good bonding with the glass substrate, and the inorganic films hold at the edge of the first glass substrate 100 Therefore, in the process of removing the first glass substrate required for ductility, it was difficult to separate the first polymer substrate including the inorganic films from the first glass substrate simply by laser irradiation. To solve this problem, a method of removing the glass substrate by applying force to the first polymer substrate in a direction different from that of the first glass substrate has been proposed. In particular, the removal of the first glass substrate is an adhesive layer between a touch screen manufactured on a first glass substrate and a display panel including a thin film transistor array and an organic light emitting diode array manufactured on another second glass substrate. In this case, a different external force remains as residual stress on the first polymer substrate of the touch screen or the second polymer substrate on the display panel side whenever the first glass substrate is removed, thereby removing the first glass substrate. Afterwards, there is a problem that the first polymer substrate and the second polymer substrate are rolled or peeled off, and even the provision of such an external force has not completely solved the problem of removing the glass substrate.

As shown in FIG. 3 , the flexible display device of the present invention has a good separation reaction by laser irradiation when the first glass substrate 100 is removed, compared with that between the first glass substrate 100 and the first polymer substrate 110 . Thus, the first plurality of buffer layers 120, the interlayer insulating film 130, and the protective film 140 of inorganic components covering the edges and outer edges of the first polymer substrate 110 have good bonding with the first glass substrate 100. The inorganic film hole 150 is formed vertically along the edge of the first polymer substrate 110 on a plane to distinguish the area from the other area, so that the first polymer substrate 110 and the first glass detached The substrate 100 is divided and the inorganic film hole 150 is separated only by the boundary, and the first glass substrate 100 can be naturally separated only by laser irradiation.

The inorganic film hole 150 is formed by removing the first plurality of buffer layers 120, the interlayer insulating film 130, and the protective film 140 of an inorganic component having good bonding with the first glass substrate 100 to a certain width, If the first polymer substrate 110 can be separated from the inorganic layered body 170 on the outside by being spaced apart from the inorganic film hole 150 as a boundary, its width can be determined within various ranges. However, depending on the method of forming the inorganic film hole 150, its size may be determined. For example, when the inorganic film hole 150 is defined by laser cutting, its width may be determined in the range of several μm. And, the inorganic film hole 150 may have the same diameter in each of the inorganic films. That is, it has a vertical cutting surface in cross section.

The drawing shown in FIG. 2 shows the shape after the first glass substrate 100 is removed, and shows a state in which some of the inorganic film patterns 170a remain at the four corners of the first polymer substrate 110 . This is a possible structure when the first glass substrate 100 is removed from the inorganic film laminate 170 in the area where the inorganic film hole 150 is not formed, and the adhesion to the side of the first polymer substrate 110 is relatively good. In addition, the partially protruding inorganic film pattern 170a may be gently formed along the side of the first polymer substrate 110 in an area where the first glass substrate 100 is absent. In addition, the inorganic film pattern 170a appears to protrude from each of the four corners, but is actually integrally connected to the plurality of inorganic films 120, 130, and 140 covering the side and top of the first polymer substrate 110. .

In addition to laser cutting, the inorganic film hole 150 may be defined together during the formation of each inorganic film 120, 130, and 140 by an exposure method, or by a dry etch method, the inorganic film 120, 130 and 140), it is possible to form an inorganic film hole 150 having a cut surface perpendicular to the laser by supplying plasma only to the corresponding area.

In this case, the shape of the inorganic films 120, 130, and 140 in the inorganic film hole 150 has a rectangular shape along the edge of the lower surface of the first polymer substrate in plan view. Also, at this time, the separation between the first polymer substrate and the first glass substrate within the inorganic film hole 150 is easy only by laser irradiation, and the first glass substrate can be removed only by simple laser irradiation.

Meanwhile, in the touch screen of the present invention, the first polymer substrate 110 is a component of polyester or a copolymer containing polyester, polyimide, or a copolymer containing polyimide. , olefin-based copolymer, polyacrylic acid or copolymer containing polyacrylic acid, polystyrene or copolymer containing polystyrene, polysulfate or copolymer containing polysulfate, polycarbonate (polycarbonate) or copolymers containing polycarbonate, polyamic acid or copolymers containing polyamic acid, copolymers containing polyamine and polyamic acid, polyvinylalcohol, polyallylamine It may include one or more polymer compounds selected from the group consisting of (polyallyamine), and its thickness may be 5 μm to 20 μm. In addition, the first polymer substrate 110 is a transparent substrate and may be the outermost surface viewed by a viewer when applied to an actual flexible display device. The aforementioned first polymer substrate 110 may be, for example, polyimide.

The plurality of first buffer layers 120 may be an oxide layer, a nitride layer, or an oxynitride layer. In some cases, it is also made in the form of a metal oxide film containing metal. The first plurality of buffer layers 120 compensates for the weak resistance to moisture permeability of the first polymer substrate 110, and is used in processes such as deposition and etching of first and second touch electrodes constituting a touch screen to be formed thereafter. The polymer substrate 110 may be protected.

Meanwhile, as shown in FIG. 5 to be described later, the touch screen 1000 includes first and second touch electrodes 122 and 124 crossing each other for touch sensing in the active area AA.

The first and second touch electrodes 122 and 124 may be provided in various shapes such as a bar shape, a diamond shape, or a polygonal shape, and are the main sensing units of the first and second touch electrodes 122 and 124 on the same layer. 122a and 124, and a bridge electrode 122b is provided on another layer at the intersection to prevent short circuit between them. In the figure, the main sensing unit 122a of the first touch electrode and the bridge electrode 122b are connected to each other through a contact hole provided in the interlayer insulating film 130 with an interlayer insulating film 130 therebetween. . In this case, the second touch electrode 124 has a shape in which the main sensing unit and the connection unit thereof are integrally formed. In some cases, the shapes of the first touch electrode 122 and the second touch electrode 124 may be changed.

In any case, the touch screen is located on the upper side of the display panel, and for display, the main sensing parts of the first and second touch electrodes 122 and 124 are made of transparent electrodes.

Meanwhile, a protective film 140 is formed to cover the first and second touch electrodes 122 and 124 and the interlayer insulating film 130 . The protective film 140 functions to protect the first and second touch electrodes 122 and 124 and prevents the influence of driving of the touch screen 1000 from interfering with the display panel.

Hereinafter, the touch screen manufacturing method of the present invention will be described.

4A to 4C are process cross-sectional views showing the touch screen manufacturing method.

As shown in FIG. 4A , the first polymer substrate 110 is coated on the first glass substrate 100 . In this case, the first polymer substrate 110 is coated by being agglomerated from the edge of the first glass substrate 100 to the inside of the first glass substrate 100 as a solution, and after curing, the edge has a certain angle of inclination. In the active region, the first polymer substrate 110 maintains flatness.

Then, on the first polymer substrate 110, a plurality of first buffer layers 120 of an oxide film, a nitride film, or an oxynitride film component are formed using a chemical vapor deposition method. Here, the plurality of first buffer layers 120 cover the inclination of the edge of the first polymer substrate 110 and protrude beyond it, so that the edge of the plurality of first buffer layers 120 is the surface of the first glass substrate 100. touches on

Next, in a shape similar to the first plurality of buffer layers 120, covering the edge of the first polymer substrate 110 and protruding more than this, on the first plurality of buffer layers 120, in turn, an interlayer insulating film ( 130) and the protective film 140 are formed.

Here, the first and second electrodes 122 and 124 provided in the active area AA of FIG. 5 to be described later pattern a transparent electrode on the first plurality of buffer layers 120 to form a first electrode sensing unit 122a. ) And a second electrode sensing unit in a direction crossing the first electrode sensing unit, and a second electrode 124 having a connection unit integrally connecting the second electrode sensing unit, wherein the first electrode sensing unit 122a and the second electrode 124, an interlayer insulating film 130 having a contact hole exposing a part of the adjacent first electrode sensing unit 122a is formed, and the contact hole of the interlayer insulating film 130 is formed. A bridge electrode 122b is connected to the adjacent first electrode sensing unit 122a through the interlayer insulating layer 130 to connect them. Here, the first electrode sensing unit 122a and the bridge electrode 122b are electrically connected to function as the first electrode 122 .

Subsequently, a protective layer 140 covering the interlayer insulating layer 130 and the bridge electrode 122b is formed.

As shown in FIG. 4B, the protective film 140 of the inorganic film component, the interlayer insulating film 130, and the first plurality of buffer layers 120 are removed from the edge of the first polymer substrate 110, thereby forming the first polymer substrate 110 An inorganic film hole 150 exposing the is formed. Meanwhile, the formation of the inorganic film hole 150 may be performed by laser cutting or by selectively dry etching only a portion of the inorganic film hole 150 . Alternatively, when the inorganic film hole 150 is formed with the first plurality of buffer layers 120, the interlayer insulating film 130, and the protective film 140, the photomask for patterning them is changed to form the edge of the first polymer substrate 110 Along, it may be provided with an inorganic film hole 150. When a photo mask is provided, the process of FIG. 4B is not performed separately, and the process of FIG. 4A may be performed.

Subsequently, as shown in FIG. 4C , laser is irradiated to the side of the first glass substrate 100 to separate the first polymer substrate 110 inside the inorganic film hole 150 from the first glass substrate 100. .

Through this separation process, the first polymer substrate 110 and the first plurality of buffer layers 120 thereon, the interlayer insulating film 130 and the protective film 140 and the first and second electrodes 122 therein, A touch screen 1000 including 124 is formed.

On the other hand, as in the above-described method, the natural peeling of the glass substrate is not limited to the touch screen, and if the structure has an inorganic film with a relatively wider edge than the polymer substrate, a display including a thin film transistor array and an organic light emitting diode array It will be applicable to the panel side as well.

However, since the polymer substrate of the display panel is a colored substrate and may not have an inclination at the edge portion, there may be relatively no difficulty in peeling the glass substrate compared to the touch screen side. Depending on the shape of the edge portion of the polymer substrate, The provision of such an inorganic film hole is selectively performed.

Hereinafter, the configuration of the flexible display device to which the touch screen is applied will be described in detail.

5 is a cross-sectional view illustrating an active area and an inactive area of the flexible display device according to the present invention.

Previously, in the active area on the touch screen side, the first plurality of buffer layers 120, the first and second electrodes 122 and 124, the interlayer insulating film 130 and the protective film 140 were formed on the first flexible substrate 110. The point of having has been described.

In addition, as shown in FIG. 5, the outside of the active area is in the non-active area, the edge of the first flexible substrate 110 has a certain inclination, and the first plurality of buffer layers 120 of inorganic film components thereon , the interlayer insulating film 130 and the protective film 140 are provided to cover the inclination, and it can be seen that these inorganic films have a vertical cutting surface.

Meanwhile, an example in which the touch routing wiring 125 is provided on the first plurality of buffer layers 120 is shown, which is formed by patterning a separate metal wiring before forming the first and second electrodes 122 and 124, or Alternatively, when the first and second electrodes 122 and 124 are double-layered, they may be formed of metal components only or may be formed on the same layer as the bridge electrode 122b of the first electrode. When the bridge electrode 122b of the first electrode and the touch routing wiring 125 are formed on the same layer, the touch routing wiring 125 may be positioned on the interlayer insulating layer 130 .

Further, on the second polymer substrate 210, a plurality of second buffer layers 220 covering the second polymer substrate 210 are formed, and the thin film transistor array 230 in the active region is formed on the plurality of second buffer layers. Two or more thin film transistors are provided on 220 to correspond to each pixel, and a second interlayer insulating film 237 covering the thin film transistors and having a protective function is provided.

Meanwhile, the second polymer substrate 210, like the first polymer substrate 110, is composed of polyester or a copolymer containing polyester, polyimide, or polyimide. Copolymers, olefinic copolymers, polyacrylic acid or copolymers containing polyacrylic acid, polystyrene or copolymers containing polystyrene, polysulfate or copolymers containing polysulfate, polycarbonate or copolymers containing polycarbonate, polyamic acid or copolymers containing polyamic acid, copolymers containing polyamine and polyamic acid, polyvinylalcohol, poly It may include one or more polymer compounds selected from the group consisting of allylamine (polyallyamine), and the thickness may be 5 μm to 30 μm. However, the second polymer substrate 210 is a colored substrate and may not be relatively transparent compared to the first polymer substrate 110 . For example, the above-described second polymer substrate 210 may be, for example, polyimide, but in this case, the second polymer substrate 210 is formed to have a different thickness and a different color from the first polymer substrate 110. outside light of can be blocked.

Here, the thin film transistor includes an active layer 231 located in a selective region of the second plurality of buffer layers 120, a gate insulating film 222 covering the active layer 231, and an upper portion of the active layer 231. The gate electrode 233 positioned in contact with the gate insulating film 222, the first interlayer insulating film 234 covering the gate electrode 233, and both sides of the active layer 231 passing through the first interlayer insulating film 234. It includes a source electrode 235 and a drain electrode 236 respectively connected to both sides of the active layer 231 through a contact hole exposing the .

Further, the second interlayer insulating film 237 has a contact hole at a connection portion between the source electrode 235 and the drain electrode 236 and the active layer 231 and covers the remaining portion.

In addition, the organic light emitting diode array 240 includes an organic light emitting diode (OLED) corresponding to each pixel, and the organic light emitting diode (OLED) has a first electrode connected to a driving thin film transistor (D-TFT) ( 241), an organic emission layer 243 provided on the first electrode 242, and a second electrode 244 on the organic emission layer 243. Here, the organic light emitting layer 243 defines a light emitting area by including a bank 242 at the boundary of each pixel, and is formed within the light emitting area.

And, to protect from external moisture or air, the encapsulation layer 250 may be included in the organic light emitting diode array 240 together with the plurality of organic light emitting diodes (OLEDs) provided for each pixel, in this case , The encapsulation layer 250 may be provided in the shape of a barrier laminate having an alternating structure of organic layers and inorganic layers to cover the upper and side portions of the organic light emitting array 240 .

Also, the display panel including the touch screen 1000, the thin film transistor array 230, the organic light emitting diode array 240, and the encapsulation layer 250 is bonded with an adhesive layer 160 interposed therebetween. After bonding, the encapsulation layer 250 covering the organic light emitting diode array 240 is formed on the first surface of the adhesive layer 160 , and the protective film 140 is in contact with the second surface.

On the other hand, in the touch screen manufacturing method of FIGS. 4A to 4C, it is shown that the first glass substrate 100 is removed after the inorganic film hole 150 is formed, but the actual removal of the first glass substrate 100 is After bonding the touch screen 1000 manufactured on the first glass substrate 100 and the display element array 2000 manufactured on the second glass substrate 200, respectively, the first glass substrate 100 It is done sequentially from elimination.

In addition, in the manufacturing method of the flexible display device of the present invention, since the removal of the first glass substrate 100 can be performed simply by laser irradiation, the process is easier compared to a known method in which an external force process is added. It is possible to solve the problem that the formed inorganic films of the inorganic component are not peeled cleanly from the edge of the first polymer substrate 110 , and the first polymer substrate 110 is degenerated when an external force is applied.

Hereinafter, a method of manufacturing a flexible display device using the above-described method of manufacturing a touch screen will be described.

6 is a process cross-sectional view illustrating a manufacturing method of the flexible display device according to the present invention. The following manufacturing process can be understood by including the cross-sectional view of FIG. 5 .

First, a first polymer substrate 110 is formed on the first glass substrate 100 (S100).

An inorganic film covering the first polymer substrate 110 on top of the first polymer substrate 110 and protruding from the edge of the first polymer substrate 110 by a certain width and in contact with the first glass substrate 100 It is formed (S110). Examples of the inorganic film include a first plurality of buffer layers 120 , an interlayer insulating film 130 and a protective film 140 . In addition, the inorganic film includes not only a single inorganic film but also a plurality of inorganic films.

The inorganic film is removed from the edge of the first polymer substrate 110 to form an inorganic film hole 150 exposing the first glass substrate 100 (S120). After the formation of the inorganic film, the formation of the inorganic film hole 150 only on the feature portion may be performed by laser cutting or a dry etching method in which plasma of an etching component is supplied by opening only the corresponding portion.

Alternatively, the removal of the inorganic film may be performed simultaneously during patterning of the inorganic film of each layer. In this case, since the diameters of the holes of each layer may not be aligned or the diameters may be different, it may be preferable to form the inorganic film hole at the edge of the first polymer substrate 110 after forming the inorganic film described above. .

A second polymer substrate 210 is formed on the second glass substrate 200 (S130).

Bonding is performed between the inorganic film and the second polymer substrate 210 via an adhesive layer 160 (S140).

Next, laser irradiation is performed on the rear surface of the first glass substrate 100 to remove the first glass substrate 100 (S150).

Next, laser irradiation is performed on the rear surface of the second glass substrate 200 to remove the second glass substrate 200 (S160).

That is, the flexible display device of the present invention recognizes the problem that the inorganic film in contact with the first glass substrate protruding outward from the first flexible substrate is not peeled off only by laser irradiation due to strong adhesion to the first glass substrate, A hole is formed in the inorganic film located at the edge of the flexible substrate by a method such as laser cutting, through which the first flexible substrate and the first glass substrate can be naturally separated.

In addition, forming a hole in the inorganic film is performed before bonding the glass substrate, and then bonding the arrays on both glass substrates in a state facing each other, and removing each glass substrate.

Here, the formation of the hole indicates that it is made only on the first glass substrate in the illustrated process flow chart, but the inorganic films on the second polymer substrate on the second glass substrate may protrude while covering the edge of the second glass substrate. It can also be applied at times.

Meanwhile, in the description of the manufacturing method of the flexible display device described above, the components formed on the first and second glass substrates are a touch screen and a thin film transistor array/organic light emitting diode array, but are not limited thereto, and may be formed by replacing each other. When the inorganic insulating films formed thereafter have a shape in which the side surface of the polymer substrate of the present invention has an inclination, they are located not only on the upper part of the polymer substrate but also on the side surface and the glass substrate, and have strong bonding between the substrate and the inorganic insulating film It can be applied by application.

Hereinafter, the shape of the inorganic film hole and various embodiments thereof will be described.

7 is a plan view of a first glass substrate showing inorganic film holes and inorganic film patterns in the touch screen manufacturing method of the present invention, and FIGS. am.

7 to 8B, on the outside of the inorganic film hole 150 on the first glass substrate 100 immediately after the inorganic film hole 150 is formed, the first plurality of buffer layers 120 formed on the first polymer substrate 110 in advance , the inorganic film laminate 170 of the laminated interlayer insulating film 130 and the protective film 140 remains.

On a plane, inside the inorganic film hole 150, the first polymer substrate 110 is positioned directly on the first glass substrate 100, and has the same configuration as the inorganic film laminate 170 on the top. In this way, the first plurality of buffer layers 120, the interlayer insulating film 130, and the protective film 140 are positioned.

9a and 9b are plan views of the touch screen showing the inorganic film hole forming step and after removing the first glass substrate in the touch screen manufacturing method according to the first embodiment of the present invention.

9A shows that the area occupied by the first polymer substrate 110 on the first glass substrate 100 is up to the active area AA and area A corresponding to a certain width around it, and the inorganic film laminate is the first polymer substrate In a shape covering 110, a film is formed more widely outward to area B than area A. The inorganic film hole 150 provided in the inorganic film laminate is provided along the edge of the first polymer substrate 110 to have a rectangular rim shape on a plane, and is provided between area A and area B. By preventing the bonding between the inorganic film laminate and the first glass substrate, the starting point of the inorganic film hole 150 in area A is determined, and the end point must be located inside the area B to prevent bonding before and after bonding, and the first glass substrate 100 ), it is possible to prevent the touch screen from sliding on the surface. Here, this frame shape is a continuous shape without a break.

On the first glass substrate 100 having the inorganic film hole 150, the first plurality of buffer layers 120, the interlayer insulating film 130, and the protective film 140 are formed outside the inorganic film hole 150 to form the first glass substrate 120. The inorganic film laminate 170 protrudes from the substrate 100, and as shown in FIG. 9B, they are bonded together in the process of removing the first glass substrate 100 by laser irradiation after bonding the two glass substrates together. Removed.

In the inorganic film hole 150 outside the first polymer substrate 110 on the first glass substrate 100, the first glass substrate 100 is exposed, and the rear surface of the first glass substrate 100 is irradiated with laser. At this time, pores are generated between the first polymer substrate 110 of different components and the first glass substrate 100, and the first glass substrate 100 at the edge of area A is opened, so that the first polymer substrate ( 110) may be separated from the first glass substrate 100. After the first glass substrate 100 is removed, the touch screen has an edge of the first polymer substrate 110 as an edge. That is, when the edge side of the first polymer substrate 110 has a certain inclination, the side having the inclination is the part of the touch screen up to the edge A in contact with the first glass substrate 100 (see FIG. 4A). is defined

10A and 10B are plan views of a touch screen showing an inorganic film hole forming step and a first glass substrate removed in a touch screen manufacturing method according to a second embodiment of the present invention.

10A shows the formation of inorganic film holes in the touch screen manufacturing method according to the second embodiment of the present invention, and the inorganic film holes 150 are formed by excluding corners of rectangular edges on a plane. In this case, as shown in FIG. 10B , the inorganic film laminate 170a on the first glass substrate 100 remains at a corner of the rectangular edge and outside the inorganic film hole 151 with a certain width. In this case, the inorganic film laminate 170a remaining outside the edge corner and the inorganic film hole 151 includes the first glass substrate 100 having a touch screen, a thin film transistor array on the lower side, and an organic light emitting diode array. 2 When bonding with the glass substrate 200, the flow of both glass substrates is controlled. That is, since the formation of the inorganic film hole 150 is performed before bonding of both glass substrates, when all the edges of the first polymer substrate 110 are exposed to the inorganic film hole, during the bonding process, the first polymer substrate 110 is exposed. In order to prevent such sliding, the inorganic film laminate 170a is brought into contact with the first glass substrate 100 only at the corners by weak force during the bonding process.

In some cases, the inorganic film laminate 170a at the corner of the inorganic film hole 150 of the first glass substrate 100 may also be removed.

As shown in FIG. 10B , when laser is irradiated to the rear surface of the first glass substrate 100 , the first glass substrate 100 is removed together with the inorganic film laminate 170a around the inorganic film hole 150 . In this case, a part of the inorganic film pattern 170a at the corner of the inorganic film hole 150 may remain.

11A and 11B are plan views of the touch screen showing the inorganic film hole forming step and after removing the first glass substrate in the touch screen manufacturing method according to the third embodiment of the present invention.

As shown in FIG. 11A, the touch screen according to the third embodiment of the present invention has inorganic film holes 150 discontinuously along the edge of the first polymer substrate 110. Such a discontinuous surface may be defined by laser cutting or dry etching only a portion corresponding to the inorganic film hole 152, for example.

In this case, as shown in FIG. 11B, after laser irradiation and removal of the first glass substrate 100, a portion of the inorganic film pattern 170a formed of the inorganic film laminate may remain, as shown in FIG. 11B. Alternatively, as shown in FIG. 9B, an inorganic film removal area having a substantially rectangular frame shape is already defined along the edge line of the first polymer substrate 110 by the inorganic film hole 150, and the laser irradiation intensity is increased. The inorganic film laminate 170 may also be removed between the inorganic film holes 150 along the edge of the first polymer substrate 110 .

On the other hand, the present invention described above is not limited to the above-described embodiments and accompanying drawings, and various substitutions, modifications, and changes are possible within a range that does not depart from the technical spirit of the present invention. It will be clear to those skilled in the art.

100: first glass substrate 110: first polymer substrate
120: first plurality of buffer layers 130: interlayer insulating film
140: protective film 150: weapon film hole
160: adhesive layer 170: inorganic laminate
200: second glass substrate 210: second polymer substrate
220: second plurality of buffer layers 230: thin film transistor array
240: organic light emitting diode array 250: encapsulation layer

Claims (12)

A first polymer substrate having a lower surface wider than an upper surface and having an inclination at a side portion;
a second polymer substrate facing the first polymer substrate;
a plurality of layers of inorganic films covering upper and side portions of the first polymer substrate and having a cut surface coincident with an edge line defining a lower surface of the first polymer substrate; and
An adhesive layer provided between the plurality of inorganic films and the second polymer substrate inside the edge line,
The flexible display device of claim 1 , wherein the edge line and the multi-layered inorganic film are in contact with each other between the first and second polymer substrates without intervening an organic layer. According to claim 1,
The flexible display device of claim 1 , wherein a cut surface of the plurality of layers of the inorganic film has a rectangular shape along an edge of a lower surface of the first polymer substrate in plan view. According to claim 2,
The flexible display device further comprises an inorganic film pattern connected to the plurality of inorganic films at each corner of the quadrangular edge. According to claim 1,
The flexible display device of claim 1 , wherein cut surfaces of the plurality of layers of the inorganic film are discontinuously provided along an edge line of the first polymer substrate. According to claim 4,
The flexible display device further includes inorganic film patterns protruding outward from the first polymer substrate between cut surfaces of the discontinuously provided inorganic film on a plane. According to claim 1,
The inorganic film includes a plurality of buffer layers, an interlayer insulating film, and a protective film. According to claim 6,
The flexible display device further includes first touch electrodes and second touch electrodes disposed vertically on the plurality of buffer layers with the interlayer insulating film as a boundary. According to claim 7,
The protective layer covers the interlayer insulating layer and the second touch electrode. According to claim 8,
The flexible display device further comprising a thin film transistor array and an organic light emitting diode array connected to the thin film transistor array on the second polymer substrate. According to claim 9,
The first and second surfaces of the adhesive layer are in contact with the organic light emitting diode array and the passivation layer, respectively. According to claim 1,
The flexible display device of claim 1 , wherein the first and second polymer substrates are polyimide. forming a first polymer substrate on a first glass substrate, the lower surface of which is wider than the upper surface, and the side of the polymer substrate is inclined;
On the first polymer substrate, covering the upper and side surfaces of the first polymer substrate, protruding a certain width from the edge line in which the lower surface of the first polymer substrate is defined, and contacting the first glass substrate. Forming an inorganic film;
Outside the edge line, the plurality of inorganic films are removed together to a predetermined width to form an inorganic film hole whose one side coincides with the edge line, and the plurality of inorganic films are brought into contact with the edge line without intervening an organic layer, exposing the first glass substrate to the inorganic film hole;
Forming a second polymer substrate on a second glass substrate;
adhering an uppermost surface of the plurality of layers of the inorganic film and the second polymer substrate to an inner side of the edge line through an adhesive layer;
removing the first glass substrate by irradiating a laser on the rear surface of the first glass substrate; and
and removing the second glass substrate by irradiating a laser on the rear surface of the second glass substrate.

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