KR20170077916A - Flexible Organic Light Emitting Diode Display Embedding In-Cell Touch Sensor - Google Patents

Abstract

The present invention relates to a flexible organic light emitting diode display device incorporating an in-cell touch sensor. The organic light emitting diode display device according to the present invention includes a flexible base film, a display element layer, an in-cap thin film layer, an adhesive layer, a touch thin film layer, a protective insulating film, a transparent ultraviolet shielding film, and a polarizing film. The display element layer has a display region formed on the flexible base film and implementing a picture and a pad portion extending in the display region. The in-cap thin film layer seals the display element layer. The adhesive layer is applied to the entire upper surface of the in-cap thin film layer. The touch thin film layer is adhesively bonded to the adhesive layer. The protective insulating film is applied to the entire upper surface of the touch thin film layer. The transparent ultraviolet shielding film is applied to the entire upper surface of the protective insulating film. The polarizing film is attached to the upper surface of the transparent ultraviolet shielding film.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a flexible organic light emitting diode

The present invention relates to a flexible organic light emitting diode display device incorporating an in-cell touch sensor. In particular, the present invention relates to an in-cell touch sensor built-in flexible organic light emitting diode display device having a structure for preventing the damage of an organic light emitting device by a laser in separating a flexible substrate from a rigid substrate by using a laser.

Various flat panel display devices have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. A flat panel display device includes a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an electroluminescence device (EL) have.

An electroluminescent display device is divided into an inorganic electroluminescent display device and an organic light emitting diode display device depending on the material of the light emitting layer, and is self-luminous device that emits itself, has a high response speed, and has a large luminous efficiency, brightness and viewing angle. 1 is a view showing a structure of an organic light emitting diode. The organic light emitting diode includes an organic electroluminescent compound layer that electroluminesces as shown in FIG. 1, and a cathode and an anode that face each other with an organic electroluminescent compound layer interposed therebetween. The organic electroluminescent compound layer includes a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and an electron injection layer layer, EIL).

In the organic light emitting diode, an excitation is formed in the excitation process when the holes and electrons injected into the anode and the cathode recombine in the light emitting layer (EML), and the organic light emitting diode emits light due to energy from the exciton. The organic light emitting diode display device displays an image by electrically controlling the amount of light generated from the emission layer (EML) of the organic light emitting diode as shown in FIG.

The organic light emitting diode display device using the characteristics of the organic light emitting diode, which is an electroluminescent device, is divided into a passive matrix type organic light emitting diode display device and an active matrix type organic light emitting diode display device. In addition, depending on the direction in which the light is emitted, it is classified into a top-emission type and a bottom-emission type.

An active matrix type flexible organic light emitting diode display device (flexible AMOLED) displays an image by controlling a current flowing in an organic light emitting diode using a thin film transistor (TFT). Flexible Organic Light Emitting Diode (OLED) display devices have completed the development of active matrix type organic light emitting diode (OLED) panels on a thin substrate of flexible polyimide material, and have developed protective cap, barrier film, circular polarization film, A printed circuit board (PCB) connection with a film (COF: Circuit On Film) and a COF, and a cover substrate.

Hereinafter, a process for manufacturing a conventional flexible organic light emitting diode display device will be described with reference to FIGS. 2A to 2G. FIGS. 2A to 2G are cross-sectional views illustrating a process of manufacturing a conventional flexible organic light emitting diode display device according to the related art.

A base substrate GS having sufficient rigidity is prepared. Here, the sufficient rigidity means that the transfer and transport and the deposition process are repeated between manufacturing equipments in order to form an element on the base substrate GS, in which the base substrate GS does not affect the quality of the device Refers to rigidity that maintains flatness without bending or deforming.

A buffer layer (NL) comprising silicon nitride is deposited over the base substrate (GS) for improved isolation and planarization. A silicon layer (SL) containing amorphous silicon is entirely coated on the buffer layer (NL). Then, an organic layer PL including polyimide is coated on the silicon layer SL. (Fig. 2A)

A display element layer TOL is formed on the organic layer PL. The display element layer TOL includes a display region for realizing an image and a pad portion extending in the display region. In this embodiment, the display element layer TOL including the organic light emitting diode display elements in which the thin film transistors and the pixel regions are arranged in an active matrix manner and the organic light emitting diodes driven by the thin film transistors are formed in each pixel region is formed .

On the display element layer TOL, it is preferable to further form a plurality of display elements for improving the image implementation ability. For example, the display element layer TOL is sealed with a thin film-type cap (TFE) to protect the display element from moisture and gas. The display element layer TOL is formed in a part of the organic layer PL.

In FIG. 2B, a display element layer (TOL) is shown connected to the right end, which represents a pad portion extending from the display element and a connection wiring. Therefore, the display elements of the display element layer TOL are kept completely sealed with the thin film film type cap (TFE). (Figure 2b)

The display element region of the display element layer TOL including the thin film type cap (TFE) is sealed with the barrier film (BF) in order to compensate the sealing ability and rigidity of the thin film type cap (TFE). A circular polarizing film (CP) is attached on the barrier film (BF). At this time, it is preferable that the circular polarizing film CP is disposed so as to completely cover the display element region where the light of image data is emitted. (Fig. 2C)

A film-like circuit board (COF) having a driving IC for driving the display panel is mounted on a pad portion exposed on one side of the display panel (right side in the drawing). The sectional shape of the display panel to which the display element, the thin film type cap (TFE), the barrier film (BF), the circular polarization film (CP) and the film type circuit board (COF) Likewise, the step has a severe shape. If the flatness of the cover substrate is not ensured when the final cover substrate is attached in this state, moisture and active gases may penetrate into the display device through the gap due to the step difference.

It is also important that the adhesive performance of the film-like circuit board (COF) attached to the pad portion is maintained in the subsequent manufacturing process. Therefore, the film-like circuit board (COF) is coated with a reinforcing adhesive (TUF) for compensating the adhesion performance and compensating for the stepped shape generated at this portion. It is preferable that the reinforcing adhesive (TUF) includes an organic adhesive material of acrylic series or silicon series in order to maintain flatness with the height of the circular polarizing film CP.

In particular, it is preferable to coat the upper surface of the terminal portion of the film-like circuit board (COF) adhered to the pad portion and the space of the upper portion of the display element layer exposed between the pad portion and the display barrier film (BF). It is more preferable to coat the space between the circular polarizer plates CP at the end of the organic layer PL including the upper surface of the film type printed substrate (COF) connected to the pad part. (Figure 2d)

After the adhesive strength of the film-like circuit board (COF) is reinforced by the reinforcing adhesive (TUF), the adhesive layer (ADH) is entirely coated on the entire surface of the base substrate GS. In particular, it is preferable that the surface is flatly applied over a region corresponding to the entire plane area of the organic layer PL. Further, in the present invention, the light emission direction proceeds in a direction in which the circular polarizing film CP is attached. Therefore, it is preferable that the adhesive layer ADH has a high optical transparency. Further, it is preferable to include an organic material so as to planarize the surface of the base substrate GS having a large level difference. Particularly, it is more preferable to include an optical adhesive which is cured with ultraviolet rays (Optical Bond).

The adhesive layer (ADH) preferably comprises an organic optical adhesive including materials of the Acrylate Esters, Acrylate Urethanes, Mercaptons series and Photoinitiator series. The adhesive layer ADH is applied so as to completely cover all the elements attached on the base substrate GS, in particular, to completely cover the upper portion of the reinforcing adhesive (TUF) for fixing the film type circuit board (COF) . (Figure 2E)

The cover substrate CG is attached via the adhesive layer ADH. After completing the attachment to the cover substrate CG to complete the display panel, a green laser LA having a wavelength band of 532 nm from the outside of the base substrate GS is irradiated into the silicon layer SL. Particularly, the entire area of the base substrate GS is uniformly scanned, and uniformly irradiated onto the entirety of the silicon layer SL. As a result, the amorphous silicon of the silicon layer SL is crystallized to separate the base substrate GS and the organic layer PL including polyimide. That is, the base substrate GS used for rigidity in the manufacturing process and the display panel formed on the organic layer PL having light-weight-pliability can be separated from each other. (Figure 2f)

The organic layer PL of the display panel separated from the base substrate GS has a very thin and flexible property. Therefore, it is preferable to further attach a protective film (PF) for protecting the organic layer PL. Further, the display-panel module is completed by connecting the film-like circuit board (COF) of the display panel to an external circuit board (PCB). Since the film type circuit board COF having high ductility is adhered to the cover substrate CG by the adhesive layer ADH, sufficient rigidity can be ensured. In this state, there is no reliability problem in connecting the external circuit board (PCB) to the film type circuit board (COF). (Figure 2g)

An organic electroluminescent display device formed on a thin and flexible organic layer rather than a thick glass substrate has been described. When the touch input sensor is attached to the organic light emitting diode display device as described above, the overall thickness of the display device is increased, and the flexibility is also greatly reduced. Therefore, there are still many problems that need to be solved to develop flexible organic light emitting diode display device with built-in touch sensor capable of flexing and folding freely.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flexible organic light emitting diode display device that maintains normal display function without being damaged even if it is folded or bent. It is another object of the present invention to provide an in-cell touch flexible organic light emitting diode display device having a built-in touch sensor and being foldable or bendable. Another object of the present invention is to provide an in-cell touch flexible organic light emitting diode display device capable of preventing the organic light emitting layer from being damaged by a laser in the process of separating the flexible display device from the rigid substrate .

In order to achieve the above object, an organic light emitting diode display device according to the present invention includes a flexible base film, a display element layer, an in-cap thin film layer, an adhesive layer, a touch thin film layer, a protective insulating film, a transparent ultraviolet shielding film, and a polarizing film. The display element layer has a display region formed on the flexible base film and implementing a picture and a pad portion extending in the display region. The in-cap thin film layer seals the display element layer. The adhesive layer is applied to the entire upper surface of the in-cap thin film layer. The touch thin film layer is adhesively bonded to the adhesive layer. The protective insulating film is applied to the entire upper surface of the touch thin film layer. The transparent ultraviolet shielding film is applied to the entire upper surface of the protective insulating film. The polarizing film is attached to the upper surface of the transparent ultraviolet shielding film.

As an example, it further includes a polyimide thin film layer and a buffer layer. The polyimide thin film layer is interposed between the base film and the display element layer. The buffer layer is interposed between the display element layer and the polyimide thin film layer.

For example, the transmittance of a 300 nm to 400 nm wavelength band laser is 70% or less in a transparent ultraviolet shielding film.

For example, the transparent ultraviolet shielding film includes an indium-zinc oxide material.

For example, the transparent ultraviolet blocking film has a thickness of 100 ANGSTROM to 300 ANGSTROM.

The organic light emitting diode display according to the present invention has a structure for preventing the organic light emitting layer from being damaged by the laser used for separating the flexible display device from the rigid substrate. By arranging the indium-zinc oxide thin film layer in the direction of laser light incidence in the organic light emitting layer, it is possible to prevent the laser from flowing into the organic light emitting layer. In addition, the indium-zinc oxide thin film layer has high transmittance to visible light, and light emitted from the organic light emitting layer can be provided without deteriorating transmittance.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a structure of an organic light emitting diode. FIG.
FIGS. 2A to 2G are cross-sectional views illustrating a process of manufacturing a flexible organic light emitting diode display device according to a related art.
3 is a cross-sectional view showing a structure of a flexible organic light emitting diode display device incorporating an in-cell touch sensor according to a first embodiment of the present invention.
4A to 4D are cross-sectional views illustrating a manufacturing process of a flexible organic light emitting diode display device having an in-cell touch sensor according to a first embodiment of the present invention.
5 is a cross-sectional view illustrating a structure of a flexible organic light emitting diode display device having an in-cell touch sensor according to a second embodiment of the present invention.
6A to 6D are cross-sectional views illustrating a process for fabricating a flexible organic light emitting diode display device having an in-cell touch sensor according to a second embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description, a detailed description of known technologies or configurations related to the present invention will be omitted when it is determined that the gist of the present invention may be unnecessarily obscured. In addition, the component names used in the following description may be selected in consideration of easiness of specification, and may be different from the parts names of actual products.

≪ Embodiment 1 >

Hereinafter, a flexible organic light emitting diode display device having an in-cell touch sensor according to a first embodiment of the present invention will be described. 3 is a cross-sectional view illustrating a structure of a flexible organic light emitting diode display device incorporating an in-cell touch sensor according to a first embodiment of the present invention.

Referring to FIG. 3, the flexible organic light emitting diode display according to the first embodiment of the present invention includes a base film PF, an organic layer PL, a display element layer TOL, an in-cap thin film layer ENC, (ADH), a touch thin film layer (TSP), a protective film (PAC), and a polarizing film (CP) are sequentially stacked. The base film (PF) is an organic film excellent in flexibility so as to be bent or folded. The organic layer PL is adhered to the upper surface of the base film PF. For example, by optical adhesive.

The display element layer TOL is deposited and / or coated on the organic layer PL. The display element layer TOL has a display region for realizing an image and a pad portion extending in the display region. For example, in the display region of the display element layer TOL, a plurality of pixel regions partitioned by scan wirings, data wirings, and drive current wirings are arranged. A thin film transistor and an organic light emitting diode connected to the thin film transistor are formed in a thin film shape in the pixel region. The pad portion is provided with connection pads and connection means for applying signals to the scan wiring, the data wiring, and the drive current wiring.

The in-cap thin film layer ENC is applied so as to cover both the upper surface and the side surface of the display element layer TOL. The in-cap thin film layer (ENC) is in direct surface contact with the display element layer (TOL), thereby preventing moisture and air from entering from the outside. The in-cap thin film layer (ENC) can be formed by applying a metal paste by surface deposition and / or surface coating. Alternatively, the organic thin film and the inorganic thin film may have a structure in which multiple layers are alternately stacked. Alternatively, a protective film excellent in water and air barrier properties may be adhered and formed.

A transparent adhesive layer (ADH) is applied to the entire upper surface of the in-cap thin film layer (ENC). The transparent adhesive layer ADH preferably has excellent transmittance to light provided by the display element layer TOL. On the upper surface of the transparent adhesive layer ADH, a touch thin film layer TSP is surface-bonded.

The touch thin film layer TSP includes a sensor wiring layer ITS including a sensor wiring extending in a lateral direction and a driving wiring layer ITL including a driving wiring extending in a longitudinal direction. The sensor wiring layer ITS and the driving wiring layer ITL may be separately formed on respective base films and then cemented. Or a structure in which a sensor wiring layer (ITS) is formed on the lower surface of one base film and a driving wiring layer (ITL) is formed on the upper surface. Alternatively, it may have a structure including a sensor wiring layer (ITS) deposited on a lower layer with a protective layer therebetween, and a driving wiring layer (ITL) formed on the upper layer.

A protective film PAC is deposited and / or applied on the entire upper surface of the touch thin film layer TSP. The protective film PAC preferably includes a material having high transmittance to light provided by the display element layer TOL, in particular, light in a visible light wavelength band. The protective film PAC is for securing the adhesive force with the polarizing film CP bonded on the surface of the touching thin film layer TSP, and is preferably excellent in interfacial adhesion property.

On the upper surface of the touch thin film layer TSP, a polarizing film CP is adhered. The polarizing film CP is surface-bonded to the entire surface of the display device for the purpose of preventing external light from being reflected and hindering display quality. The polarizing film CP is laminated on the uppermost layer of the flexible organic light emitting diode display device and preferably has a robust structure that can prevent damage due to external impact or foreign matter. For example, a hard coating layer may be further applied to the upper surface of the polarizing film (CP).

Thus, the flexible organic light-emitting diode display device according to the present invention has a thickness of ultra-thin film and excellent flexibility. You can freely bend or fold to use the carry and store or display functions. Further, the touch sensor has an in-line touch structure in which a touch sensor is interposed between the display element layer TOL and the polarizing film CP.

Hereinafter, a method of manufacturing a flexible organic light emitting diode display device having an in-cell touch sensor according to a first embodiment of the present invention will be described. 4A to 4D are cross-sectional views illustrating a manufacturing process of a flexible organic light emitting diode display device having an in-cell touch sensor according to a first embodiment of the present invention.

First, as shown in Fig. 4A, a display substrate DP is formed. The lower buffer layer NL1 is deposited on the entire surface of the lower rigid substrate GS1. The lower buffer layer NL1 is formed of silicon nitride (SiNx). A lower sacrificial layer SL1 is deposited on the entire upper surface of the lower buffer layer NL1. The lower sacrificial layer SL1 is formed of amorphous silicon (a-Si). An organic layer PL is applied on the lower sacrificial layer SL1. The organic layer PL is formed of a polyimide which is resistant to high temperatures.

A display element layer TOL is formed on the upper surface of the organic layer PL. The display element layer TOL includes a thin film transistor and an organic light emitting diode. The display devices for an organic light emitting diode display device can be applied to the presently developed ones, and a detailed description thereof will be omitted. The display element layer TOL may be formed only on a part of the upper surface of the organic layer PL. It is preferable that the in-cap thin film layer (ENC) is surface-bonded while completely covering the display element layer (TOL). For example, it may be formed to be fully surface-bonded with the upper surface and side surfaces of the display element layer TOL.

Next, as shown in Fig. 4B, a touch substrate TP is formed. An upper buffer layer NL2 is deposited on the entire surface of the upper rigid substrate GS2. The upper buffer layer NL2 is formed of silicon nitride (SiNx). An upper sacrificial layer SL2 is deposited on the entire upper surface of the upper buffer layer NL2. The upper sacrificial layer SL2 is formed of amorphous silicon (a-Si).

A protective film (PAC) is deposited on the entire upper surface of the upper sacrificial layer SL2. The upper sacrificial layer SL2 under the protective film PAC is a portion to be peeled together with the rigid substrate GS2 in the future. Therefore, it is preferable to form another protective film (PAC), rather than directly forming the display element on the upper sacrificial layer SL2. The protective layer (PAC) preferably includes a transparent organic material having a high transmittance to visible light. After the upper sacrificial layer SL2 and the rigid substrate GS2 are separated, the polarizing film CP is attached to the protective film PAC. Therefore, it is preferable that the protective film (PAC) includes a material having an excellent interfacial adhesion with the film material.

A touch thin film layer (TSP) is formed on the protective film (PAC). For example, a transparent conductive material is deposited on a protective film (PAC) and patterned to form a driving wiring to form a driving wiring layer (ITL). A protective layer (not shown) is deposited on the entire upper surface of the driving wiring layer (ITL). A transparent conductive material is deposited on the protective layer and patterned to form a sensor wiring to form a sensor wiring layer (ITS).

The display substrate DP and the touch substrate TP are bonded together as shown in Fig. 4C. The in-cap thin film layer ENC which is the uppermost layer of the display substrate DP and the touch thin film layer TSP which is the uppermost layer of the touch substrate TP are arranged to face each other and are adhered to each other via the adhesive layer ADH therebetween .

A laser LA having a wavelength range of 300 nm to 400 nm is irradiated from the outside of the upper rigid substrate GS2 to the upper sacrificial layer SL2. Since the cross section of the laser LA is very small and the substrate is relatively wide, it is preferable to irradiate the entire surface of the upper sacrificial layer SL2 evenly while moving up and down while scanning left and right. As a result, a phase change occurs in the upper sacrificial layer SL2 and is removed to separate the upper rigid substrate GS2 and the upper buffer layer NL2 from the touch thin film layer TSP.

The polarizing film (CP) is surface-bonded onto the entire surface of the exposed touching thin film layer (TSP). Thereafter, the laser LS having a wavelength range of 300 nm to 400 nm is irradiated from the outside of the lower rigid substrate GS1 to the lower sacrificial layer SL1. As a result, a phase change occurs in the lower sacrificial layer SL1 and is removed to separate the lower rigid substrate GS1 and the lower buffer layer NL1 from the organic layer PL.

Although not shown in the drawings, a buffer layer may be further laminated between the organic layer PL and the display element layer TOL. The buffer layer may have a multi-layer structure in which an inorganic layer and an organic layer are alternately stacked. In particular, a metal layer may be added to the buffer layer so that the laser used for separating the lower rigid substrate GS1 is not transmitted to the display element layer TOL. Thereafter, the flexible base film PF is attached to the lower surface of the exposed organic layer PL. Then, a flexible organic light emitting diode display device having a structure as shown in FIG. 4D is completed.

In the process for manufacturing the flexible organic light emitting diode display device, first, a flexible display device is manufactured on a rigid substrate, and then the rigid substrate is peeled from the flexible display device. A laser is used in the peeling process, and the laser has a strong energy, so that the organic light emitting layer may be damaged if the laser touches the organic light emitting layer.

Particularly, when separating the upper rigid substrate GS2, there is a high possibility that the laser LA is irradiated to the organic light emitting layer. Therefore, when irradiating the laser LA, it is preferable to irradiate the upper sacrificial layer SL2 with as much focus as possible. Even so, a part of the laser can be transmitted below the upper sacrificial layer SL2. In this case, the laser can damage the other thin film layer, particularly, the organic light emitting layer of the display element layer TOL.

≪ Embodiment 2 >

Hereinafter, a flexible organic light emitting diode display device having an in-cell touch sensor according to a second embodiment of the present invention will be described. 5 is a cross-sectional view illustrating a structure of a flexible organic light emitting diode display device having an in-cell touch sensor according to a second embodiment of the present invention.

5, a flexible organic light emitting diode display device according to a second embodiment of the present invention includes a base film PF, an organic layer PL, a display element layer TOL, an in-cap thin film layer ENC, A structure in which a transparent adhesive layer ADH, a touch thin film layer TSP, a protective insulating film PAC, a transparent ultraviolet shielding film IZO, and a polarizing film CP are sequentially laminated. The base film (PF) is an organic film excellent in flexibility so as to be bent or folded. The organic layer PL is adhered to the upper surface of the base film PF. For example, by optical adhesive.

The display element layer TOL is deposited and / or coated on the organic layer PL. The display element layer TOL has a display region for realizing an image and a pad portion extending in the display region. For example, in the display region of the display element layer TOL, a plurality of pixel regions partitioned by scan wirings, data wirings, and drive current wirings are arranged. A thin film transistor and an organic light emitting diode connected to the thin film transistor are formed in a thin film shape in the pixel region. The pad portion is provided with connection pads and connection means for applying signals to the scan wiring, the data wiring, and the drive current wiring.

The in-cap thin film layer ENC is applied so as to cover both the upper surface and the side surface of the display element layer TOL. The in-cap thin film layer (ENC) is in direct surface contact with the display element layer (TOL), thereby preventing moisture and air from entering from the outside. The in-cap thin film layer (ENC) can be formed by applying a metal paste by surface deposition and / or surface coating. Alternatively, the organic thin film and the inorganic thin film may have a structure in which multiple layers are alternately stacked. Alternatively, a protective film excellent in water and air barrier properties may be adhered and formed.

A transparent adhesive layer (ADH) is applied to the entire upper surface of the in-cap thin film layer (ENC). The transparent adhesive layer ADH preferably has excellent transmittance to light provided by the display element layer TOL. On the upper surface of the transparent adhesive layer ADH, a touch thin film layer TSP is surface-bonded.

The touch thin film layer TSP includes a sensor wiring layer ITS including a sensor wiring extending in a lateral direction and a driving wiring layer ITL including a driving wiring extending in a longitudinal direction. The sensor wiring layer ITS and the driving wiring layer ITL may be separately formed on respective base films and then cemented. Or a structure in which a sensor wiring layer (ITS) is formed on the lower surface of one base film and a driving wiring layer (ITL) is formed on the upper surface. Alternatively, it may have a structure including a sensor wiring layer (ITS) deposited on a lower layer with a protective layer therebetween, and a driving wiring layer (ITL) formed on the upper layer.

A protective insulating film (PAC) is deposited and / or coated on the entire upper surface of the touch thin film layer (TSP). The protective insulating film PAC preferably includes a material having high transmittance to light provided by the display element layer TOL, particularly light in a visible light wavelength range. In addition, the protective insulating film PAC is for securing the adhesive force with the polarizing film CP bonded onto the surface of the touching thin film layer TSP, and is preferably excellent in the interface adhesion property.

A transparent ultraviolet blocking film IZO is deposited on the entire upper surface of the protective insulating film PAC. The transparent ultraviolet blocking film IZO preferably includes a transparent material having a transmittance of 70% or less for a laser having a wavelength range of 300 nm to 400 nm. In particular, the transparent ultraviolet (IZO) blocking film is preferably formed of indium zinc oxide. Indium-zinc oxide is a kind of transparent oxide. A similar transparent oxide is indium-tin oxide (Indium Tin Oxide). However, the indium-tin oxide has a transmittance exceeding 90% for a laser having a wavelength range of 300 nm to 400 nm. Therefore, indium-tin oxide is not suitable for use as a transparent ultraviolet (IZO) barrier film.

The indium-zinc oxide constituting the transparent ultraviolet blocking film (IZO) is a transparent oxide and can have conductivity. Therefore, if there is no protective insulating film PAC, the transparent ultraviolet shielding film IZO is directly adhered to the touching thin film layer TSP. In the touch thin film layer (TSP), the wirings are patterned. When these wirings are in surface contact with the transparent ultraviolet protection film (IZO), all the wirings are electrically connected to fail to function as wiring. Therefore, it is preferable that the protective insulating film PAC includes a material having excellent insulating performance. Unlike the first embodiment, it is not a simple protective film but an insulating film.

On the upper surface of the transparent ultraviolet shielding film IZO, a polarizing film CP is adhered. The polarizing film CP is surface-bonded to the entire surface of the display device for the purpose of preventing external light from being reflected and hindering display quality. The polarizing film CP is laminated on the uppermost layer of the flexible organic light emitting diode display device and preferably has a robust structure that can prevent damage due to external impact or foreign matter. For example, a hard coating layer may be further applied to the upper surface of the polarizing film (CP).

Thus, the flexible organic light-emitting diode display device according to the present invention has a thickness of ultra-thin film and excellent flexibility. You can freely bend or fold to use the carry and store or display functions. Further, the touch sensor has an in-line touch structure in which a touch sensor is interposed between the display element layer TOL and the polarizing film CP.

Hereinafter, a method of manufacturing a flexible organic light emitting diode display device having an in-cell touch sensor according to a second embodiment of the present invention will be described. 6A to 6D are cross-sectional views illustrating a process for fabricating a flexible organic light emitting diode display device having an in-cell touch sensor according to a second embodiment of the present invention.

First, as shown in Fig. 6A, a display substrate DP is formed. The lower buffer layer NL1 is deposited on the entire surface of the lower rigid substrate GS1. The lower buffer layer NL1 is formed of silicon nitride (SiNx). A lower sacrificial layer SL1 is deposited on the entire upper surface of the lower buffer layer NL1. The lower sacrificial layer SL1 is formed of amorphous silicon (a-Si). An organic layer PL is applied on the lower sacrificial layer SL1. The organic layer PL is formed of a polyimide which is resistant to high temperatures.

A display element layer TOL is formed on the upper surface of the organic layer PL. The display element layer TOL includes a thin film transistor and an organic light emitting diode. The display devices for an organic light emitting diode display device can be applied to the presently developed ones, and a detailed description thereof will be omitted. The display element layer TOL may be formed only on a part of the upper surface of the organic layer PL. It is preferable that the in-cap thin film layer (ENC) is surface-bonded while completely covering the display element layer (TOL). For example, it may be formed to be fully surface-bonded with the upper surface and side surfaces of the display element layer TOL.

Next, as shown in Fig. 6B, a touch substrate TP is formed. An upper buffer layer NL2 is deposited on the entire surface of the upper rigid substrate GS2. The upper buffer layer NL2 is formed of silicon nitride (SiNx). An upper sacrificial layer SL2 is deposited on the entire upper surface of the upper buffer layer NL2. The upper sacrificial layer SL2 is formed of amorphous silicon (a-Si).

A transparent ultraviolet blocking film IZO is deposited on the entire upper surface of the upper sacrificial layer SL2. The transparent ultraviolet blocking film (IZO) deposits indium-zinc oxide to a thickness of 100 Å to 300 Å. The transparent ultraviolet blocking film (IZO) made of indium-zinc oxide has a transmittance of 70% or less for a laser having a wavelength range of 300 nm to 400 nm.

A protective insulating film (PAC) is deposited on the entire upper surface of the transparent ultraviolet shielding film IZO. The protective insulating film (PAC) preferably includes a transparent organic material having an excellent transmittance to visible light. A touch thin film layer (TSP) is deposited on the transparent ultraviolet shielding film IZO, and indium-zinc oxide may be conductive. Therefore, it is preferable that a protective insulating film (PAC) having an insulating property is interposed between the transparent ultraviolet shielding film IZO and the touch thin film layer TSP.

A touch thin film layer (TSP) is formed on the protective insulating film (PAC). For example, a transparent conductive material is deposited on a protective insulating film (PAC) and patterned to form a driving wiring to form a driving wiring layer (ITL). A protective layer (not shown) is deposited on the entire upper surface of the driving wiring layer (ITL). A transparent conductive material is deposited on the protective layer and patterned to form a sensor wiring to form a sensor wiring layer (ITS).

The display substrate DP and the touch substrate TP are bonded together as shown in Fig. 6C. The in-cap thin film layer ENC which is the uppermost layer of the display substrate DP and the touch thin film layer TSP which is the uppermost layer of the touch substrate TP are arranged to face each other and are adhered to each other via the adhesive layer ADH therebetween .

A laser having a wavelength range of 300 nm to 400 nm is irradiated from the outside of the upper rigid substrate GS2 to the upper sacrificial layer SL2. As a result, a phase change occurs in the upper sacrificial layer SL2, and the upper rigid substrate GS2 and the upper buffer layer NL2 are separated from the transparent ultraviolet blocking layer IZO. It is preferable to irradiate the upper sacrificial layer SL2 as much as possible when irradiating the laser. Even so, a part of the laser can be transmitted below the upper sacrificial layer SL2. In this case, the laser can damage the other thin film layer, particularly, the organic light emitting layer of the display element layer TOL. However, in the present invention, the transparent ultraviolet shielding film IZO is disposed directly under the upper sacrificial layer SL2 to prevent the energy of the laser from being transmitted to other thin film layers.

The polarizing film CP is adhered to the entire surface of the exposed transparent ultraviolet blocking film IZO. Thereafter, a laser having a wavelength range of 300 nm to 400 nm is irradiated from the outside of the lower rigid substrate GS1 to the lower sacrificial layer SL1. As a result, a phase change occurs in the lower sacrificial layer SL1 and is removed to separate the lower rigid substrate GS1 and the lower buffer layer NL1 from the organic layer PL.

Although not shown in the drawings, a buffer layer may be further laminated between the organic layer PL and the display element layer TOL. The buffer layer may have a multi-layer structure in which an inorganic layer and an organic layer are alternately stacked. In particular, a metal layer may be added to the buffer layer so that the laser used for separating the lower rigid substrate GS1 is not transmitted to the display element layer TOL. Thereafter, the flexible base film PF is attached to the lower surface of the exposed organic layer PL. Thus, a flexible organic light emitting diode display device having the structure as shown in FIG. 6D is completed.

In the second embodiment of the present invention, unlike the first embodiment, it further includes a transparent ultraviolet (IZO) film laminated on the touch thin film layer TSP. The transparent ultraviolet shielding film IZO is a thin film containing indium-zinc oxide and has a transmittance of 70% or less with respect to light in the ultraviolet region, which is the wavelength range of the laser used for separating the flexible display from the rigid substrate. Therefore, the laser can be prevented from flowing into the organic light emitting layer disposed below the touch thin film layer TSP, thereby protecting the organic light emitting layer.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

DP: display substrate TP: touch substrate
GS1: Lower rigid substrate GS2: Upper rigid substrate
NL1: Lower buffer layer NL2: Upper buffer layer
SL1: lower sacrificial layer SL2: upper sacrificial layer
PL: organic layer IZO: transparent ultraviolet shielding film
TOL: Display element layer PAC: Protective insulating film
ENC: In-cap thin film layer TSP: Touch thin film layer
ADH: adhesive layer ITL: driving wiring layer
ITS: sensor wiring layer

Claims (5)

Flexible base film;
A display element layer formed on the flexible base film, the display element layer having a display region for realizing an image and a pad portion extending in the display region;
An in-cap thin film layer for sealing the display element layer;
An adhesive layer applied over the entire upper surface of the in-cap thin film layer;
A touch thin film layer adhesively bonded to the adhesive layer;
A protective insulating film coated on the entire upper surface of the touch thin film layer;
A transparent ultraviolet shielding film applied over the entire upper surface of the protective insulating film; And
And a polarizing film attached to the upper surface of the transparent ultraviolet shielding film.
The method according to claim 1,
A polyimide thin film layer sandwiched between the base film and the display element layer; And
And a buffer layer interposed between the display element layer and the polyimide thin film layer.
The method according to claim 1,
The transparent ultraviolet blocking film
Wherein the transmittance of the 300 nm to 400 nm wavelength band laser is 70% or less.
The method according to claim 1,
The transparent ultraviolet blocking film
A flexible organic light emitting diode display comprising an indium-zinc oxide material.
The method according to claim 1,
The transparent ultraviolet blocking film
A flexible organic light emitting diode display device having a thickness of 100 ANGSTROM to 300 ANGSTROM.

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