KR20170080311A - Flexible display device - Google Patents

Abstract

The flexible display device of the present invention can prevent a crack from occurring by forming a blocking pattern in an outer area and arrange the display area array structure differently from neighboring sub-pixels so that cracks are generated inside the display area due to bending stress, Thereby preventing propagation of the radio wave.
Accordingly, the present invention provides an effect of improving reliability by preventing the occurrence of defects in devices and panels due to bending stress.
In addition, it provides an advantage of securing highly bendable devices and backplane technology for flexible display devices using existing infrastructure.

Description

[0001] FLEXIBLE DISPLAY DEVICE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible display device, and more particularly, to a flexible display device implemented on a flexible substrate such as plastic.

In recent information society, the importance of display devices as visual information delivery media is getting more emphasized, and in order to take a major position in the future, it is necessary to meet requirements such as low power consumption, thinning, light weight, and high image quality.

A flexible display device that is not damaged even if the display device is folded or rolled is expected to emerge as a new technology in the display device field.

The flexible display device is called a scroll display device. It is implemented on a thin substrate such as plastic, and is one of the next generation display devices in that it is not damaged when folded or rolled like paper. A thin film transistor liquid crystal display device, an organic light emitting display device, or an electrophoretic display device which can be made thin to 1 mm or less can be used.

2. Description of the Related Art A liquid crystal display device is an apparatus that expresses an image using optical anisotropy of a liquid crystal. The liquid crystal display device has better visibility than the conventional cathode-ray tube, and the average power consumption is smaller than that of the cathode-ray tube having the same screen size, and the amount of heat generated is also small.

Since the organic electroluminescent display device itself emits light itself, visibility is good even when it enters a dark place or an outside light. In addition, since the response speed, which is an important criterion for judging the performance of the mobile display device, is fast, a complete moving image can be realized. In addition, the organic light emitting display device can be slim with a variety of mobile devices such as a mobile phone because it is possible to have an ultra-thin design.

In order to realize such a flexible display device, it is necessary to secure the flexibility of the substrate, and in order to secure such a substrate flexibility, a plastic flexible substrate is used instead of the conventional glass substrate.

Hereinafter, the basic structure and operating characteristics of the organic light emitting display will be described in detail with reference to the drawings.

1 is a diagram for explaining the principle of light emission of a general organic light emitting diode.

In general, an organic light emitting display device includes an organic light emitting diode as shown in FIG.

The organic light emitting diode includes an anode 18 as a pixel electrode, a cathode 28 as a common electrode, and organic compound layers 30a, 30b, 30c, 30d and 30e formed therebetween.

The organic compound layers 30a, 30b, 30c, 30d and 30e are composed of a hole transport layer 30b and an electron transport layer 30d, and a light emission layer 30c interposed between the hole transport layer 30b and the electron transport layer 30d .

A hole injection layer 30a is interposed between the anode 18 and the hole transport layer 30b and an electron injection layer 30e is interposed between the cathode 28 and the electron transport layer 30d in order to improve the luminous efficiency. do.

When the positive and negative voltages are applied to the anode 18 and the cathode 28, the organic light emitting diode having the above structure passes through the hole transporting layer 30b and the electron transporting layer 30d One electron is moved to the light emitting layer 30c to form an exciton. Then, light is generated when the exciton transitions from an excited state to a ground state, that is, a stable state.

An organic light emitting display displays an image by arranging sub-pixels having organic light emitting diodes of the above-described structure in a matrix form and selectively controlling the sub-pixels with a data voltage and a scan voltage.

At this time, the organic light emitting display device is divided into an active matrix method using a thin film transistor (TFT) as a passive matrix type or a switching element. The active matrix method selectively turns on the active element TFT to select the sub-pixel and maintains the emission of the sub-pixel with the voltage held in the storage capacitor.

A typical organic light emitting display device driven in this manner includes a substrate on which a plurality of TFTs and organic light emitting diodes are formed, and an encapsulation layer formed on the substrate.

In order to fabricate such an organic light emitting display device with a flexible display device, a TFT array and an organic light emitting diode are formed based on a material having flexibility.

As the substrate material of the flexible display device, plastic such as PET (polyethylene terephthalate) or PEN, metal foil or the like may be used. As the flexible TFT device material, organic or soluble oxide may be used. And the like.

However, the technology for increasing the flexibility by applying structural modification of devices and arrays is very limited, in addition to the technology of thinning and neutral plane when manufacturing flexible panels using inorganic devices and backplanes.

As described above, when a flexible display device is manufactured, TFTs are usually formed on a flexible substrate using organic and inorganic materials, which indicates that the overall degree of flexibility is absolutely dependent on the flexibility of the substrate itself. It also proves that the flexibility of the substrate itself before the device formation is a way to maximize the overall flexibility.

However, when manufacturing devices on a flexible substrate, or after bending the substrate after fabrication, physical stresses affect the entire substrate. This again acts as a stress on the respective layers of the TFT array and the organic light emitting diode, thereby causing a physical defect in the device such as a crack.

That is, although the conventional method can provide a backplane that is flexible to a certain level of bending stress, it has a disadvantage that it is difficult to secure reliability of the device against extreme bending stress.

It is an object of the present invention to provide a flexible display device capable of preventing the occurrence of defects in devices and panels due to mechanical stress that occurs during panel and backplane bending.

Other objects and features of the present invention will be described in the following description of the invention and the claims.

According to an aspect of the present invention, there is provided a flexible display device including: a plurality of barrier patterns disposed at a periphery of a non-display area of a substrate to block crack propagation when cracks occur; A TFT having a layout different from the neighboring sub-pixels, and an electroluminescent (EL) region.

At this time, the blocking pattern may be arranged to form a plurality of rows.

At this time, the blocking pattern may be staggered with respect to the blocking pattern of the neighboring rows.

The odd-numbered row blocking pattern and the even-numbered row blocking pattern are arranged in the same arrangement, and the blocking pattern of the odd-numbered column and the blocking pattern of the even-numbered column may be staggered from each other.

The blocking pattern may be randomly arranged without forming a column.

The blocking patterns may be arranged in the rear row at positions corresponding to spaces between the blocking patterns in the front row.

The blocking pattern may be formed of the same material on the same layer as the gate wiring and the data wiring constituting the TFT.

The sub-pixel may be configured such that the gate electrode of the odd-numbered column sub-pixel is connected to the gate line of the odd-numbered row, and the gate electrode of the even-numbered column sub-pixel is connected to the gate line of the even- have.

The EL region may have a shape in which the EL region of the even-numbered column is inverted with respect to the EL region of the odd-numbered column.

As described above, the flexible display device according to an embodiment of the present invention is characterized in that cracks are prevented from propagating into the display area due to bending stress after fabrication of the backplane.

Accordingly, the present invention provides an effect of improving reliability by preventing the occurrence of defects in devices and panels due to bending stress.

In addition, the present invention provides an effect of securing a highly bendable device and a backplane technology for a flexible display device using an existing infrastructure.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining a principle of light emission of a general organic light emitting diode. FIG.
2 is a block diagram illustrating an example of a flexible display device according to an embodiment of the present invention.
3 is a perspective view schematically showing a structure of a flexible display device according to an embodiment of the present invention.
Fig. 4 is an exemplary view showing a state in which a plurality of panels for a flexible display device are arranged on a mother substrate; Fig.
5 is a cross-sectional view illustrating a structure of a flexible display device according to an embodiment of the present invention.
6 is a cross-sectional view exemplarily showing a structure of an organic compound layer in a flexible display device according to an embodiment of the present invention shown in Fig. 5;
FIG. 7 is a schematic view showing a part of a cross-sectional structure of a flexible display device according to an embodiment of the present invention; FIG.
FIG. 8 is a plan view exemplarily showing a part E1 of an outer area in the flexible display device according to the embodiment of the present invention shown in FIGS. 3 and 4. FIG.
FIGS. 9A and 9B illustrate circuit configurations for a portion E2 of a display area in a flexible display device according to an embodiment of the present invention shown in FIGS. 3 and 4. FIG.
10 is an exemplary diagram showing a circuit configuration for a sub-pixel of a flexible display device;

Hereinafter, preferred embodiments of the flexible display device according to the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification. The dimensions and relative sizes of the layers and regions in the figures may be exaggerated for clarity of illustration.

It will be understood that when an element or layer is referred to as being another element or "on" or "on ", it includes both intervening layers or other elements in the middle, do. On the other hand, when a device is referred to as "directly on" or "directly above ", it does not intervene another device or layer in the middle.

The terms spatially relative, "below," "lower," "above," "upper," and the like, And may be used to easily describe the correlation with other elements or components. Spatially relative terms should be understood to include, in addition to the directions shown in the drawings, terms that include the different directions of the elements in use, or in operation. For example, when inverting an element shown in the figures, an element described as "below" or "beneath" of another element may be placed "above" another element. Thus, the exemplary term "below" can include both downward and upward directions.

The terminology used herein is for the purpose of describing embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. &Quot; comprise "and / or" comprising ", as used in the specification, means that the presence of stated elements, Or additions.

In this specification, a top emission type organic light emitting display device refers to an organic light emitting display device in which light emitted from an organic light emitting diode is emitted to an upper part of an organic light emitting display device. Here, the organic light emitting display device refers to an organic light emitting display device in which light emitted from an organic light emitting diode is emitted in a direction of a top surface of a substrate on which a thin film transistor for driving an organic light emitting display device is formed.

In this specification, a bottom emission type organic light emitting display device refers to an organic light emitting display device in which light emitted from an organic light emitting diode is emitted to a lower portion of an organic light emitting display device. This means that an organic light emitting display device in which light emitted from an organic light emitting diode is emitted in a direction of a lower surface of a substrate on which a thin film transistor for driving an organic light emitting display device is formed.

As used herein, the flexible display device refers to a flexible display device, which includes a bendable display device, a rollable display device, an unbreakable display device, a foldable display device, Display device, and the like. In this specification, the organic light emitting display is one example of various flexible display devices.

2 is a block diagram illustrating an example of a flexible display device according to an embodiment of the present invention. At this time, FIG. 2 shows an organic electroluminescence display device as an example of a flexible display device.

2, a flexible display device according to an embodiment of the present invention includes an image processing unit 115, a data conversion unit 114, a timing control unit 113, a data driving unit 112, a gate driving unit 111, (116) may be included.

The image processing unit 115 performs various image processing such as setting a gamma voltage to realize the maximum luminance according to the average image level using the RGB data signals RGB, and then outputs RGB data signals RGB. The image processor 115 generates a driving signal including at least one of the RGB data signal RGB as well as the vertical synchronizing signal Vsync, the horizontal synchronizing signal Hsync, the data enable signal DES and the clock signal CLK Output.

The timing controller 113 receives one or more of the vertical synchronization signal Vsync, the horizontal synchronization signal Hsync, the data enable signal DES and the clock signal CLK from the image processing unit 115 or the data conversion unit 114 And is supplied with a drive signal. The timing control section 113 generates a gate timing control signal GCS for controlling the operation timing of the gate driving section 111 and a data timing control signal DCS for controlling the operation timing of the data driving section 112, .

The timing controller 113 outputs the data signal DATA corresponding to the gate timing control signal GCS and the data timing control signal DCS.

The data driver 112 samples and latches the data signal DATA supplied from the timing controller 113 in response to the data timing control signal DCS supplied from the timing controller 113, And outputs it. The data driver 112 outputs the converted data signal DATA through the data lines DL1 to DLm. The data driver 112 is formed in the form of an IC (Integrated Circuit).

The gate driving unit 111 outputs the gate signal while shifting the level of the gate voltage in response to the gate timing control signal GCS supplied from the timing control unit 113. [ The gate driver 111 outputs a gate signal through the gate lines GL1 to GLn. The gate driver 111 may be formed in the form of an IC or a gate-in-panel (GIP) method in the display panel 116.

The display panel 116 may be implemented with a sub-pixel structure including, for example, a red sub-pixel SPr and a green sub-pixel SPg and a blue sub-pixel SPb. That is, one pixel P is composed of RGB sub-pixels SPr, SPg, SPb. However, the present invention is not limited thereto, and may include a white sub-pixel.

3 is a perspective view schematically showing a structure of a flexible display device according to an embodiment of the present invention. 3 illustrates an organic light emitting display device in which a flexible circuit board is fastened. 3 shows a structure of a flexible display device according to an embodiment of the present invention in a state in which the flexible display device is not bent.

FIG. 4 is an exemplary view showing a state in which a plurality of panels for a flexible display device are arranged on a mother substrate.

5 is a cross-sectional view illustrating an exemplary structure of a flexible display device according to an exemplary embodiment of the present invention, and is a cross-sectional view taken along line A-A of FIG. 5 illustrates a state in which only the light emitting layer is provided on the substrate for the sake of convenience.

FIG. 6 is a cross-sectional view illustrating the structure of an organic compound layer in an organic light emitting display according to an embodiment of the present invention shown in FIG.

FIG. 7 is a schematic view showing a part of a cross-sectional structure of a flexible display device according to an embodiment of the present invention, and shows a display region and a partial cross-section of a non-display region and an outer region. The display region includes a plurality of sub-pixels arranged in a matrix in a plan view, each sub-pixel including a red sub-pixel emitting red light, a green sub-pixel emitting green light, and a blue sub- - pixels. In FIG. 7, for convenience of explanation, only one sub-pixel has a cross-sectional structure as an example.

7, the outer area is shown separately from the non-display area, and the outer area is shown to be wider than the non-display area. However, this is for the sake of convenience of description. Actually, the outer area is a region .

Referring to FIG. 3, the flexible display device according to the embodiment of the present invention includes a panel 100 for displaying an image and a flexible circuit board 150 connected to the panel 100.

The panel 100 is provided on the substrate 101 and includes a panel part 110 divided into an active area AA and a pad area PA and a part of the active area AA, And a thin film encapsulation layer 140 formed on the substrate.

The active area AA is formed in a display area DA where a plurality of sub-pixels are disposed and actually displays an image and a display area DA formed outside the display area DA, And a non-display area (NA) that transmits the display area (NA). At this time, the thin film sealing layer 140 may be formed on the panel part 110 while covering a part of the display area DA and the non-display area NA.

At this time, the panel part 110 exposed without being covered by the thin film sealing layer 140 constitutes a pad part PA where the pad is formed.

The non-display area NA is located around the edge of the display area DA or may be referred to as a peripheral area, a peripheral circuit area, an edge area, or a bezel area since various circuits for displaying an image are arranged.

That is, various elements that do not display an image may be disposed in the non-display area NA.

The components arranged in the non-display area NA may include various ICs and drive circuitry such as a gate driver IC or a data driver IC. The various ICs and driving circuit portions may be mounted on the substrate 101 in a GIP (gate in panel) or connected to the substrate 101 in a TCP (Tape Carrier Package) or a COF (Chip on Film) method.

The substrate 101 may be a flexible flexible substrate. At this time, the flexible substrate can be made of plastic having excellent heat resistance and durability.

For example, the substrate 101 may be in the form of a film including one selected from the group consisting of a polyester-based polymer, a silicon-based polymer, an acrylic polymer, a polyolefin-based polymer, and copolymers thereof. Specifically, the substrate 101 may be formed of a material selected from the group consisting of polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polysilane, polysiloxane, polysilazane, polycarbosilane, But are not limited to, polyacrylate, polymethacrylate, polymethylacrylate, polymethylmetacrylate, polyethylacrylate, polyethylmetacrylate, (PEEK), polypropylene (PP), polyimide (PI), polystyrene (PS), polyacetal (POM), polyetheretherketone (PEEK), olefin copolymer (COC), cyclic olefin polymer , Polyethersulfone (PES), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), polycarbonate (PC), polyvinylidene fluoride (PVDF), perfluoroalkyl polymer Acrylonitrile-butadiene-acrylonitrile polymer (SAN), and combinations thereof.

However, the present invention is not limited thereto, and various flexible materials may be used.

Although the substrate 101 is shown in FIG. 3 as having a rectangular parallelepiped shape, the shape of the substrate 101 is not limited thereto and may be variously formed.

In the case of the bottom emission type in which an image is realized in the direction of the substrate 101, the substrate 101 must be formed of a transparent material. However, in the case of the top emission type in which the image is implemented in the direction opposite to the substrate 101, the substrate 101 does not necessarily have to be formed of a transparent material. In this case, the substrate 101 can be formed of metal. When the substrate 101 is formed of metal, the substrate 101 may include at least one metal selected from the group consisting of carbon, iron, chromium, manganese, nickel, titanium, molybdenum and stainless steel, no.

On the upper surface of the substrate 101, a panel portion 110 is disposed. The term " panel unit 110 " referred to in this specification collectively refers to an organic light emitting diode and a TFT array for driving the same, and includes an active area AA for displaying an image and a pad area PA for displaying an image It means. Further, the TFT array provided over the substrate 101 and the substrate 101 can be collectively referred to as a backplane.

At this time, although not shown, pixels are arranged in a matrix form in the active area AA, and driving elements and other parts such as a scan driver and a data driver for driving the pixels are located outside the active area AA.

On the upper surface of the substrate 101, a thin film encapsulation layer 140 is formed to cover a part of the panel part 110. The organic light emitting diode included in the panel unit 110 is made of an organic material and easily deteriorated by external moisture or oxygen. Therefore, the panel unit 110 must be sealed to protect the organic light emitting diode. The thin film encapsulation layer 140 has a structure in which a plurality of inorganic films and organic films are alternately laminated by a means for sealing the panel part 110. By sealing the panel part 110 with the thin film sealing layer 140 instead of the sealing substrate, the organic light emitting display device can be made thin and flexible.

At this time, the portion that is not covered by the thin film encapsulation layer 140 and is exposed forms the pad region PA described above.

An integrated circuit chip (not shown) may be mounted on the pad area PA of the panel 100 constructed in this manner by a chip on glass (COG) method.

On the flexible circuit board 150, electronic elements (not shown) for processing a driving signal are mounted by a chip on film (COF) method, and an external signal is supplied to the flexible circuit board 150 A connector (not shown) may be installed.

The flexible circuit board 150 may be folded rearward of the panel 100 so that the flexible circuit board 150 faces the rear surface of the panel 100. At this time, an anisotropic conductive film (not shown) may be used to electrically connect the terminal portion of the panel portion 110 and the connection portion of the flexible circuit board 150 with each other.

The flexible display device constructed as described above can be formed on the large-sized mother board 200 as shown in FIG. In other words, a plurality of display areas DA are defined in the large-sized mother substrate 200, and a TFT array and an organic light emitting diode can be formed in each of the display areas DA. Thereafter, the large-sized mother board 200 may be cut along the scribe line SL and separated into a plurality of panels 100. FIG.

At this time, the flexible display device according to the embodiment of the present invention forms a blocking pattern in the non-display area (NA), that is, the outer area outside the panel 100 to primarily block the propagation of cracks, And the array structure is arranged differently from the neighboring sub-pixels. In this case, it is possible to prevent a crack from propagating into the display area DA due to bending stress after manufacturing the backplane.

That is, in the embodiment of the present invention, a cutoff pattern is formed in the outer area when fabricating the flexible backplane. At this time, the cutoff pattern can block crack propagation through arrangements such as arranging the cutoff patterns of the back row at positions corresponding to the space between the cutoff patterns of the front row. This is because when the mechanical stress is applied by the continuous bending of the substrate 101 after the fabrication of the device on the flexible substrate 101 or after the fabrication of the substrate 101 from the scribe line SL to the non-display area NA and the display area DA It is possible to prevent the crack from propagating.

Further, in the embodiment of the present invention, the array structure is arranged differently from the neighboring sub-pixels in the display area DA to minimize crack propagation propagated according to pattern regularity in the display area DA.

Referring to Figs. 5 to 7, as described above, each pixel in the display area DA may be configured to include red, green, and blue sub-pixels.

Each sub-pixel includes an organic light emitting diode and an electronic element electrically connected to the organic light emitting diode. The electronic device may include at least two or more TFTs, storage capacitors, and the like. The electronic device is electrically connected to the wirings and is driven by receiving an electrical signal from a driving element outside the panel portion. The array of electronic elements and wirings electrically connected to the organic light emitting diode is referred to as a TFT array.

In FIG. 7, only the driving TFTs for driving the organic light emitting diode and the organic light emitting diode are illustrated for each sub-pixel. However, the present invention is not limited to the illustrated embodiment, but may be applied to a plurality of TFTs, storage capacitors, Various wires may be further included.

The TFT shown in FIG. 7 is a top gate type and includes an active layer 124, a gate electrode 121, and source / drain electrodes 122 and 123 sequentially. The present invention is not limited to the top gate type of the TFT shown in the drawings, but various types of TFTs can be employed.

The TFT basically includes a switching transistor and a driving transistor.

Although not shown, the switching transistor is connected to a scan line and a data line, and transmits a data voltage input to the data line to the driving transistor according to a switching voltage input to the scan line. The storage capacitor is connected to the switching transistor and the power supply line, and stores a voltage corresponding to a difference between a voltage received from the switching transistor and a voltage supplied to the power supply line.

The driving transistor is connected to the power supply line and the storage capacitor to supply the organic light emitting diode with an output current proportional to the square of the difference between the voltage stored in the storage capacitor and the threshold voltage, and the organic light emitting diode emits light by the output current.

The driving transistor includes an active layer 124, a gate electrode 121 and source / drain electrodes 122 and 123, and the first electrode 118 of the organic light emitting diode is connected to the drain electrode 123 of the driving transistor .

That is, the driving transistor includes a buffer layer 115a formed on the substrate 101, and a first insulating layer 115b formed on the substrate 101 on which the active layer 124 and the active layer 124 formed on the buffer layer are formed. And a second insulating layer 115c formed on the substrate 101 having the gate electrode 121 and the gate electrode 121 formed on the first insulating layer 115b. And source / drain electrodes 122 and 123 formed on the second insulating layer 115c and electrically connected to the source / drain regions of the active layer 124 through the first contact holes.

At this time, the buffer layer 115a may be formed of a single layer or multiple layers of two or more layers, and may be formed to protect a TFT formed in a subsequent process from impurities such as alkali ions flowing out from the substrate 101. [

The active layer 124 may be formed of an oxide semiconductor.

When the active layer 124 is formed using an oxide semiconductor, it has a merit that it can be applied to a large-area display while ensuring uniform characteristics while satisfying high mobility and constant current test conditions.

In recent years, interest and activity have been concentrated on transparent electronic circuits. An oxide TFT using an oxide semiconductor as an active layer 124 has an advantage of being used in a transparent electronic circuit since it has high mobility and can be manufactured at a low temperature have.

However, the present invention is not limited thereto. The active layer 124 may be formed of an amorphous silicon film, a polycrystalline silicon film obtained by crystallizing amorphous silicon, an organic semiconductor or the like.

The gate electrode 121 may be formed of an aluminum-based metal such as aluminum (Al) or an aluminum alloy, a copper-based metal such as copper (Cu) or a copper alloy, molybdenum (Mo) And a low resistance opaque conductive material such as chromium (Cr), tantalum (Ta), and titanium (Ti) can be used. However, they may have a multilayer structure including two conductive films having different physical properties.

A first insulating layer (115b) and the second insulation layer (115c) is in a dual layer made of a single layer, or a silicon nitride film and a silicon oxide film made of an inorganic insulating material such as silicon nitride (SiNx) or silicon oxide (SiO ₂₎ Lt; / RTI >

The source electrode 122 and the drain electrode 123 may be formed of an aluminum-based metal such as aluminum or an aluminum alloy, a copper-based metal such as copper or a copper alloy, Low resistance opaque conductive materials such as tantalum and titanium can be used. However, they may have a multilayer structure including two conductive films having different physical properties.

However, the structure of such a TFT is not limited to the above-described example, and can be variously modified.

The third insulating layer 115d may be formed on the substrate 101 on which the driving transistor is formed and the third insulating layer 115d may be formed of an inorganic insulating material such as a silicon nitride film or a silicon oxide film.

At this time, a planarizing layer 115e made of a predetermined organic insulating material may be formed on the third insulating layer 115d. However, the present invention is not limited thereto, and the third insulating layer 115d may serve as the planarization layer 115e.

The drain electrode 123 of the driving transistor is electrically connected to the first electrode 118 through the third insulating layer 115d and the second contact hole formed in the planarization layer 115e.

A bank 115f may be formed at the boundary of sub-pixels above the planarization layer 115e. The bank 115f divides each sub-pixel and prevents the light of a specific color outputted from the adjacent sub-pixel from being mixed and outputted.

The organic light emitting diode may include a first electrode 118, an organic compound layer 130, and a second electrode 128.

The organic compound layer 130 may further include various organic layers 130a, 130b, 130d, and 130e for efficiently transporting carriers of holes or electrons to the light-emitting layer 130c in addition to the light- .

The organic layers 130a, 130b, 130d and 130e are formed by sequentially stacking a hole injection layer 130a, a hole transport layer 130b, a second electrode 128 and a light emitting layer 130c between the first electrode 118 and the light emitting layer 130c. An electron injection layer 130e and an electron transport layer 130d which are positioned between the electron injection layer 130d and the electron injection layer 130d.

The first electrode 118 is formed on the substrate 101 having the TFT array and the organic compound layer 130 and the second electrode 128 are sequentially stacked on the first electrode 118.

The light emitting layer 130c is an EL light emitting layer having an organic material and / or inorganic nanoparticles that emit light by electroluminescence (EL), and is interposed between the first electrode 118 and the second electrode 128. [ For example, the sub-pixel region partitioned by the bank 115f may be referred to as an EL region in which light of a specific color is emitted.

The light emitting layer 130c may be composed of a single layer or multiple layers of two or more layers.

The light emitting layer 130c may include red, green, and blue light emitting layers 130cr, 130cg, and 130cb that emit red, green, and blue light corresponding to the red, green, and blue sub-pixels, respectively.

At this time, as the EL material, there is an organic material or an inorganic material. When the organic EL material is used, there is a high molecular organic EL material or a low molecular organic EL material. The organic EL material may include one or more than two kinds of host materials and a luminescent material which is a luminescent compound.

The first electrode 118 and the second electrode 128 are electrodes for supplying holes and electrons to the light-emitting layer 130c having an EL material.

As the first electrode 118, a thin film of metal, conductive oxide, conductive polymer, or the like may be used as an anode. For example, a transparent conductive film such as Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO), and a metal having a good workability for hole injection such as gold and chromium And conductive polymers such as polyaniline, polyacetylene, polyalkyl thiophene derivatives and polysilane derivatives.

As the second electrode 128, a thin film of metal, conductive oxide, conductive polymer, or the like may be used as the cathode. For example, magnesium alloys such as MgAg, aluminum alloys such as AlLi, AlCa, and AlMg, alkali metals such as Li and Ca, alloys of alkali metals, .

Based on this structure, the organic light emitting diode has a structure in which holes injected from the first electrode 118 and electrons injected from the second electrode 128 are coupled to each other in the light emitting layer 130c via the transport layer for transportation, And light of a wavelength corresponding to the energy difference in the light emitting layer 130c is generated.

The organic compound layer 130 may be formed in the form of an island on the first electrode 118 between the banks 115f. However, the present invention is not limited thereto, and the organic layers 130a, 130b, 130d, and 130e other than the light emitting layer 130c may be deposited on the entire surface of the substrate 101 without using FMM (Fine Metal Mask).

A multilayer thin film encapsulation layer 140 may be formed on the substrate 101 in the display area DA where the second electrode 128 is formed.

The organic light emitting diode included in the panel portion is composed of an organic material and easily deteriorated by external moisture or oxygen. Therefore, the panel portion must be sealed to protect such an organic light emitting diode. The thin film sealing layer 140 may have a structure in which a plurality of inorganic films and organic films are alternately stacked by means of sealing the panel portion. However, the present invention is not limited thereto. By sealing the panel portion with the thin film sealing layer 140 instead of the sealing substrate, the hybrid display device can be made thin and flexible.

At this time, the portions that are not covered by the thin film encapsulation layer 140 and are exposed form the above-described pad regions.

The first passivation layer 140a, the organic layer 140b and the second passivation layer 140c are sequentially formed on the substrate 101 on which the organic light emitting diode is formed, Thereby forming the thin film encapsulation layer 140. However, the number of the inorganic films and the organic films constituting the thin film encapsulation layer 140 is not limited thereto.

The present invention can use a metal can bag, a glass can bag, a thin film encapsulation (TFE), or the like in addition to the above-described face seal method in a manner of sealing the panel portion .

A multilayer protective film 145 is placed opposite to the entire surface of the substrate 101 including the secondary protective film 140c so that the substrate 101 and the protective film 145 are transparent, A pressure-sensitive adhesive 146 may be interposed.

At this time, the protective film 145 may be composed of a cover glass.

On the protective film 145, a circular polarizer 150 may be attached to prevent reflection of light incident from the outside.

A pad portion 116 may be formed on the substrate 101. The pad portion 116 may be formed on the substrate 101 of the display area DA. 7, the pad portion 116 is formed on the first insulating layer 115b in the substrate 101 of the display area DA, but the present invention is not limited thereto. The pad portion 116 may be formed on the substrate 101 or on the buffer layer 115a.

The pad portion 116 may be formed of the same material as the gate electrode 121 on the same layer as the gate line 121 and a gate driver IC for applying a gate signal to the gate line. The pad portion 116 is connected to the source electrode 122 and the drain electrode 123 in the case where the pad portion 116 is configured to connect the data line and the data driver IC that applies the data signal to the data line, The same material may be formed on the same layer.

Next, a wiring 126 may be formed on the substrate 101 in the non-display area NA. The wiring 126 can transmit a signal by electrically connecting the pad portion 116 of the display area DA with the driving circuit part of the non-display area NA or the gate driver IC and the data driver IC. 7, the wiring 126 is formed of the same material as the source electrode 122 and the drain electrode 123, but the present invention is not limited thereto. The wiring 126 may be formed of the same material as the gate electrode 121 or may be integrally formed on the same layer as the pad portion 116.

The wiring 126 may be connected to another wiring pattern 116p. The wiring pattern 116p can be formed of the same material as the gate electrode 121 on the same layer.

Here, the flexible display device according to the embodiment of the present invention is characterized in that a plurality of blocking patterns 160 are formed in the outer area EA outside the non-display area NA.

7, the shielding pattern 160 is formed on the buffer layer 115a in the substrate 101 of the outer region EA, but the present invention is not limited thereto. The shielding pattern 160 may be formed on the substrate 101 or on the first insulating layer 115b or the second insulating layer 115c.

The blocking pattern 160 may be formed of the same material on the same layer as the gate wiring, that is, the gate electrode 121 and the gate line. In another embodiment, the blocking pattern 160 may be formed of the same material on the same layer as the data line, that is, the source electrode 122, the drain electrode 123, and the data line.

The interconnection pattern 160 and the interconnection 126 and the interconnection pattern 116p may be protected by the third insulating layer 115d, but the present invention is not limited thereto.

The blocking pattern 160 may be staggered or irregularly arranged with respect to neighboring rows to effectively prevent cracks due to bending stress from propagating into the display area DA, which will be described in detail with reference to the drawings.

FIG. 8 is a plan view illustrating a portion E1 of an outer area in the flexible display device according to the embodiment of the present invention shown in FIGS. 3 and 4. FIG.

On the other hand, Figs. 9A and 9B are plan views showing, by way of example, a circuit configuration for a portion E2 of the display area in the flexible display device according to the embodiment of the present invention shown in Figs. 3 and 4. Fig.

10 is an exemplary diagram showing a circuit configuration for a sub-pixel of a flexible display device.

Here, the sub-pixel shown in FIGS. 9A, 9B, and 10 includes a transistor 1C (Capacitor) structure including a switching transistor, a driving transistor, a capacitor, and an organic light emitting diode. However, the present invention is not limited to this, and when a compensation circuit is added, it can be configured in various ways such as 3T1C, 4T2C, 5T2C, and the like.

8, cracks (see the arrows) propagating from the scribe line SL are firstly blocked by the blocking pattern 160 disposed in the outer area EA according to the embodiment of the present invention .

As described above, the physical bending stress applied to the substrate itself when the device is fabricated on the flexible substrate or after the fabrication acts as a factor that can cause defects in the device. That is, when the bending stress is continuously applied after the inorganic element is formed on the flexible substrate, cracks of the inorganic film and device failure due to the crack can be caused. This suggests that a flexible display device capable of ensuring robust characteristics in terms of bending stress in view of device and panel reliability of the flexible display device is required.

In the present invention, in order to minimize the occurrence of backplane defects due to bending stress while maintaining the performance of the TFT at the time of manufacturing a device on a flexible substrate, a shielding pattern 160 for blocking propagation of cracks is formed in the outer region EA . The blocking patterns 160 may be staggered with respect to neighboring rows or the blocking patterns 160 of the rear row may be disposed at positions corresponding to spaces between the blocking patterns 160 of the front row. In addition, the blocking pattern 160 may be randomly arranged without forming a column.

That is, the applicant observed a phenomenon in which a crack due to bending stress propagated from the scribe line SL into the non-display area NA including the GIP and the display area DA. Thus, the present invention is to suppress this through the blocking pattern 160 to minimize damage due to mechanical stress inside the backplane.

As described above, this blocking pattern 160 may be arranged to form a plurality of rows. In addition, the blocking patterns 160 may be staggered with respect to the blocking patterns 160 of neighboring rows.

In this case, in each of the odd-numbered row blocking patterns 160 and the even-numbered row blocking patterns 160, the odd-numbered row blocking patterns 160 and the even-numbered row blocking patterns 160 are staggered The present invention is not limited thereto.

The blocking patterns 160 may be randomly arranged so as not to form a row, or they may be irregularly arranged.

In addition, the blocking pattern 160 may have a different arrangement from the blocking patterns 160 of the odd-numbered columns and the blocking patterns 160 of the even-numbered columns.

That is, in the shield pattern 160 according to the embodiment of the present invention, the shield patterns 160 of the rear row are arranged at positions corresponding to the spaces between the shield patterns 160 of the front row to block or reduce the propagation of the cracks Any arrangement is possible, if at all possible.

In addition, the applicant of the present invention can confirm that the propagation of the crack propagates more easily according to the regularity of the pattern in the display area DA, and accordingly, the sub-pixel structure in the display area DA is irregularly or irregularly arranged Lt; / RTI >

9A, 9B, and 10, the flexible organic EL display device includes a gate line GL arranged in a first direction and a gate line GL arranged in a second direction crossing the first direction Pixels P11, P12, P13, P14, P21, P22, P23 and P24 are defined by the data line DL and the driving power supply line VDDL.

The switching transistor SW, the driving transistor DR, the capacitor Cst, the compensation circuit CC and the organic light emitting diode (OLED) are connected to one sub-pixel P11, P12, P13, P14, P21, P22, P23, OLED) may be included.

The organic light emitting diode OLED operates to emit light in accordance with the driving current generated by the driving transistor DR.

The switching transistor SW operates in response to a gate signal supplied through the gate line GL so that a data signal supplied through the data line DL is stored as a data voltage in the capacitor Cst.

The driving transistor DR operates so that a driving current flows between the driving power supply line VDDL and the ground wiring GND in accordance with the data voltage stored in the capacitor Cst.

The compensation circuit CC compensates the threshold voltage of the driving transistor DR and the like. The compensation circuit CC may consist of one or more transistors and capacitors. The configuration of the compensation circuit (CC) is very various, and a detailed illustration and description thereof are omitted.

As described above, the flexible display device according to an embodiment of the present invention having such a structure differs from the sub-pixels adjacent to the array structure in the display area DA according to the pattern regularity in the display area DA Thereby minimizing propagation of propagated cracks.

9A, the gate electrodes of the sub-pixels P11 and P21 of the first column are connected to the first gate line GL, while the gate electrodes of the sub-pixels P12 and P22 of the second column are connected to the first gate line GL. And the gate electrode may be connected to the second gate line GL. Next, the gate electrodes of the sub-pixels P13 and P23 in the third column are connected to the first gate line GL while the gate electrodes of the sub-pixels P14 and P24 in the fourth column are connected to the second gate And may be configured to be connected to the line GL.

In other words, the sub-pixels P11, P21, P13 and P23 of the odd-numbered columns are connected to the gate line GL of the odd-numbered row and the sub-pixels P12, P22, P14 and P24 May be configured so that the gate electrode is connected to the gate line GL of the even-numbered row. However, the present invention is not limited to this. In the present invention, the gate electrodes GL of the even-numbered rows are connected to the gate electrodes GL of the sub-pixels P11, P21, P13 and P23 of the odd- The sub-pixels P12, P22, P14, and P24 of the row may be configured so that the gate electrode is connected to the gate line GL of the odd-numbered row.

In this case, the electroluminescence (EL) region of the even-numbered column may have an inverted form with respect to the EL region of the odd-numbered column.

As another example, referring to FIG. 9B, the array structures may be arranged in a staggered arrangement in the display area DA, that is, in a zigzag form in the horizontal direction.

In this case, the gate lines GL may be arranged in a zigzag manner in the horizontal direction. In this case, the TFTs and the EL regions in the even-numbered columns are inverted with respect to the TFTs and the EL regions in the odd-numbered columns, but the present invention is not limited thereto. They may have the same shape.

However, the present invention is not limited thereto. The present invention can be applied to a structure of sub-pixels P11, P12, P13, P14, P21, P22, P23 and P24 in the display area DA, It is applicable in any case where it is placed irregularly or irregularly.

While a great many are described in the foregoing description, it should be construed as an example of preferred embodiments rather than limiting the scope of the invention. Therefore, the invention should not be construed as limited to the embodiments described, but should be determined by equivalents to the appended claims and the claims.

101: Substrate 160: Breaking pattern
DA: Display area DL: Data line
DR: driving transistor EA: outer region
GL: Gate line NA: Non-display area
P11, P12, P13, P14, P21, P22, P23, P24:
SL: scribe line SW: switching transistor
VDDL: Power supply line

Claims (9)

A substrate divided into a display area composed of a plurality of sub-pixels and a non-display area around the display area;
A plurality of blocking patterns disposed on an outer periphery of the non-display area of the substrate to block crack propagation when cracks occur; And
And a TFT having an arrangement different from neighboring sub-pixels and an electroluminescence (EL) region provided in the sub-pixel. The flexible display device according to claim 1, wherein the blocking pattern is arranged to form a plurality of rows. 3. The flexible display device according to claim 2, wherein the cutoff patterns are staggered with respect to a cutoff pattern of neighboring rows. 3. The semiconductor memory device according to claim 2, wherein the blocking patterns of the odd-numbered columns and the blocking patterns of the even-numbered columns have the same arrangement,
Numbered column and the even-numbered column are arranged so as to be staggered from each other. The flexible display device according to claim 1, wherein the blocking pattern is randomly arranged without forming a column. The flexible display device according to any one of claims 2 and 4, wherein the blocking patterns are disposed at positions corresponding to spaces between the blocking patterns of the front row. The flexible display device according to claim 1, wherein the blocking pattern is made of the same material as the gate wiring and the data wiring constituting the TFT. 2. The method of claim 1, wherein the sub-
The gate electrode of the odd-numbered sub-pixel is connected to the gate line of the odd-numbered row,
And the gate electrode of the sub-pixel in the even-numbered column is connected to the gate line of the even-numbered row. The flexible display device according to claim 1, wherein the EL region has a shape in which an EL region in an even-numbered column is inverted with respect to an EL region in an odd-numbered column.

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