KR102327466B1 - Method for manufacturing a flexible display device - Google Patents

Abstract

The present specification discloses a method of manufacturing a display device. The method includes: patterning, on one surface of a support substrate on which a plurality of unit display panel areas are disposed, an area between the cut lines of each unit panel with a light non-transmissive material; bonding a first surface of a mother substrate made of a flexible material to a patterning surface of the support substrate; stacking a color filter layer on the second surface of the mother substrate for each area of the unit display panel; scribing a cut line along a boundary line of the unit display panel; and separating the support substrate from the mother substrate by irradiating laser light to the entire area of the support substrate.

Description

Method for manufacturing a flexible display device {METHOD FOR MANUFACTURING A FLEXIBLE DISPLAY DEVICE}

The present invention relates to a flexible display device and a method for manufacturing the same.

Flat panel displays (FPDs) are used in various types of electronic products, including mobile phones, tablet PCs, and notebook computers. Specific examples of the flat panel display device include a liquid crystal display device (LCD), an organic light emitting display device (OLED), a plasma display panel device (PDP), and a quantum dot display device (Quantum Dot). display device), field emission display device (FED), electrophoretic display device (EPD), etc., which in common use a flat panel display panel that implements an image as an essential component. However, the flat panel display panel has a structure in which a pair of transparent insulating substrates face to face with each other with a unique light emitting or polarized light or other optical material layer interposed therebetween.

The flat panel display device as described above is generally manufactured through a process in which a plurality of pieces are formed in a matrix shape on a brittle substrate like a semiconductor chip such as a large-scale integrated circuit, and the substrate is cut and separated in units of devices.

As a method used for cutting and separating brittle substrates such as glass, silicon, ceramic, etc., the substrate is cut by a diamond blade with a thickness of about 50 to 200 μm rotating at high speed and The thickness direction of the substrate by dicing to form a cutting groove on the substrate and a scribing wheel made of diamond having a thickness of about 0.6 to 2 mm to form a cutting groove on the surface of the substrate Two methods of scribing that generate cracks with

First, since the dicing uses a very thin blade, it is also suitable for cutting a substrate having a thin film or a convex portion formed on its surface. However, in dicing, frictional heat is generated in the area where the blade is being cut, and the cutting is performed while supplying cooling water to this area. It cannot be said that That is, in the case of dicing, it is actually difficult to completely remove the cooling water after dicing, and if there is residual water due to incomplete removal of the cooling water, corrosion may occur on the metal part of the flat panel display. . In addition, dicing has a problem in that the cutting time is longer than that of scribing, and furthermore, productivity is not good.

On the other hand, since scribing does not require any cooling water, the yield of the product is better than that of dicing, and since the cutting time is shorter than that of dicing, it has the advantage of being excellent in productivity. However, in a process in which a flexible substrate is used, improvement measures are needed to effectively perform ash or residue treatment.

An object of the present specification is to provide a flexible display device and a method of manufacturing the same. More specifically, an object of the present specification is to provide a manufacturing method for effectively separating a unit display panel from a mother substrate.

According to an embodiment of the present specification, a method of manufacturing a display device is provided. The method may include: patterning, on one surface of a support substrate on which a plurality of unit display panel areas are disposed, an area between the cut lines of each unit panel with a light non-transmissive material; bonding a first surface of a mother substrate made of a flexible material to a patterning surface of the support substrate; stacking a color filter layer on the second surface of the mother substrate for each area of the unit display panel; scribing a cut line along a boundary line of the unit display panel; and separating the support substrate from the mother substrate by irradiating laser light to the entire area of the support substrate.

According to the embodiment of the present specification, it is possible to prevent panel contamination by residues after separation of the flexible substrate and the support substrate. In addition, according to the exemplary embodiment of the present specification, the process of removing the outer region of the unit display panel may be simplified, and the impact applied to the display panel during this process may be minimized.

1 is a diagram illustrating a method of manufacturing an organic light emitting display device according to the related art.
2 is a plan view of an organic light emitting display device according to an exemplary embodiment of the present specification.
3 is an exemplary view of a substrate according to an embodiment of the present specification.
FIG. 4 is an enlarged view of a portion of the substrate shown in FIG. 3 .
5 is a view showing a line to be cut according to an embodiment of the present specification.
6 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment of the present specification.

In describing the embodiments of the present specification, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, order, or number of the elements are not limited by the terms. When it is described that a component is “connected”, “coupled” or “connected” to another component, the component may be directly connected or connected to the other component, but other components may be interposed between each component. It will be understood that each component may be “interposed” or “connected”, “coupled” or “connected” through another component. Reference to a device or layer “on” another device or layer includes any intervening layer or other device directly on or in the middle of another device. The size and thickness of each component shown in the drawings are shown for convenience of description, and the present invention is not limited to the size and thickness of the illustrated component.

Each feature of the various embodiments herein may be partially or wholly combined or combined with each other, and may be technically various interlocking and actuation by those skilled in the art, and each embodiment may be implemented independently of each other or together in a related relationship. may be carried out.

Hereinafter, embodiments of the present specification will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a method of manufacturing an organic light emitting display device according to the related art.

The organic light emitting display device includes an upper substrate 100 and a color filter layer 200 . It may be configured to include an organic light emitting layer 300 , a lower substrate 150 , a glass substrate 400 , and the like.

The upper substrate 100 and the lower substrate 150 are plates for forming a mechanical structure of a cell of a display device, and in the case of a flexible display device, they are made of a material such as a plastic film having excellent ductility.

The color filter layer 200 expresses a color using the light emitted from the organic light emitting layer 300 .

The organic light emitting layer 300 may include a thin film transistor (TFT) layer and an electroluminescent layer. The thin film transistor layer is formed on the lower substrate 150 and is a layer in which switch elements supplying a data voltage to the pixel electrode are arranged. A pad part may be positioned on one side of the thin film transistor layer. The pad part is a connection part formed for signal connection between the panel and the driver IC. The electroluminescent layer is a layer that emits light to the outside by stimulation of electrical energy, and in the case of an organic light emitting display device, an organic element emitting light to the outside by electrical stimulation is located in the electroluminescent layer.

The glass substrate 400 is attached to the upper substrate 100 and the lower substrate 150 to support each substrate during the process. The upper substrate 100 and the lower substrate 150 are attached to the glass substrate 400 and transported.

The organic light emitting display device may be manufactured through the following process.

(a) A color filter layer 200 is formed on one surface of the upper substrate 100, and a boundary line of each cell is drawn (scribing). The upper substrate 100 is attached to the organic substrate 400 .

(b) The upper substrate 100 and the lower substrate 150 on which the organic light emitting layer 300 is formed are bonded to each other.

(c) The glass substrate 400 attached to the upper substrate 100 is removed with a laser.

(d) The area between the boundary lines of each cell in the upper substrate 100 is removed by manually applying a physical force. Thereafter, the upper substrate 100 is cut into cells, and subsequent processes are performed for each cell.

In the process of the above method, an impact was applied to the upper substrate in step (d), or residual ash was generated, thereby lowering the panel manufacturing yield. Therefore, a method to solve these problems is requested.

2 is a plan view of an organic light emitting display device according to an exemplary embodiment of the present specification.

The organic light emitting diode display according to the present specification includes a lower substrate SUB and a barrier film BF. The barrier film BF and the lower substrate SUB are bonded to each other via a cotton encapsulant PSA. The barrier film BF is made of a film material for protecting display elements formed on the lower substrate SUB.

The organic light emitting diode display is divided into a display area AA and a non-display area NA. The display area AA is an area for directly displaying video information expressed by the display device, and is disposed in the center of the display device. The non-display area NA is disposed around the display area AA and does not perform a display function, but is an area in which necessary elements are disposed. An organic light emitting diode and thin film transistors for driving the organic light emitting diode are formed in the display area AA. In the non-display area NA, a gate driving device GIP, a square device EIP, and a data driving device DIC necessary to perform a display function are disposed. The gate driving device GIP and the square device EIP may be simultaneously formed with the thin film transistor of the display area AA. Meanwhile, the data driving device DIC may be attached to one side of the display device.

The ground line GND is disposed to surround the display area AA and the driving elements GIP and EIP disposed around the display area AA. The base line GND may be branched from the data driving device DIC.

The data driver DIC is disposed on one side, for example, an upper side of the lower substrate SUB. In particular, the data driver DIC may be directly attached to the lower substrate SUB. The gate driver GIP is disposed on one side, for example, a left side of the lower substrate SUB. The square element EIP is disposed on the other side of the lower substrate SUB, for example, on the right side. The gate driver GIP and the square element EIP may also be manufactured as a direct circuit element and attached to the lower substrate SUB. Alternatively, in order to narrow the width of the left and right non-display areas NA, the display elements may be directly formed in the non-display area NA.

3 is an exemplary view of a substrate according to an embodiment of the present specification.

The substrate is a plate for forming a unit structure (unit panel) of a cell of a display device, and in the case of a flexible display device, it may be made of a plastic film material (eg, polyimide, etc.) having excellent ductility. 3 shows the mother substrate 100 on which a plurality of cells, ie, unit display panels 101, can be simultaneously manufactured. The upper panel of the display device may be formed by stacking the color filter layer on the mother substrate 100 . In addition, the mother substrate 100 may be provided in a lower panel attachment process in a state in which it is bonded to a support substrate (eg, a glass substrate).

Meanwhile, in the region 102 between the cut lines (scribe lines) of the display panels, a light non-transmissive material is patterned. The material is a kind of shield pattern, and the patterned region 102 is not affected by the light even when the laser light is irradiated to the mother substrate and the support substrate. Accordingly, the region 102 between the planned cutting lines (scribe lines) is continuously attached to the support substrate during the light irradiation process, and the region 102 is supported in the separation process of the support substrate and the parent substrate 100 . It is removed from the parent substrate together with the substrate. The patterning is formed on one surface of the support substrate (the surface on which the support substrate and the mother substrate are adhered). In this case, the mother substrate 100 may be coated in the form of a film on the patterned surface of the support substrate.

After the support substrate and the parent substrate are bonded, the color filter layer is laminated. In this case, the color filter layer is laminated on a surface (second surface) opposite to the surface (first surface) on which the support substrate and the mother substrate 100 are bonded.

Thereafter, a line to be cut is formed along the boundary of the unit display panel 101 . That is, a scribe line is drawn outside the color filter layer formed on the unit display panel 101 . In this case, the cut line (scribe line) may be drawn with a laser. In a subsequent process, the unit display panel 101 is separated individually along the cut line.

When the upper panel (support substrate, parent substrate, and color filter layer) of the display device is completed including the above process, the upper panel is bonded to the lower panel. A transistor layer, an organic light emitting layer, and the like are stacked on the lower panel.

When bonding of the upper panel and the lower panel is completed, the supporting substrate of the upper panel is removed. The removal of the support substrate may be performed through a process of irradiating laser light to the entire area of the support substrate. At this time, under the influence of laser light, shrinkage/expansion occurs at the interface between the support substrate and the parent substrate, and the adhesion is separated. On the other hand, since the patterned portion 102 reflects or absorbs laser light, there is no effect on the interface, so that the support substrate and the parent substrate are not separated. Accordingly, the region 102 between the cut lines (scribe lines) is continuously attached to the support substrate during the light irradiation process, and the region 102 is supported in the separation process of the support substrate and the parent substrate 100 . It is removed from the parent substrate together with the substrate.

FIG. 4 is an enlarged view of a portion of the substrate shown in FIG. 3 .

FIG. 4(a) is a part of FIG. 3(a), and FIG. 4(b) is a part of FIG. 3(b). As can be seen from the enlarged drawing, a line to be cut (scribe line)) is drawn along the periphery of the unit panel, and the outer area is patterned with a laser shield. The cut line is drawn as deep as the parent substrate.

5 is a view showing a line to be cut according to an embodiment of the present specification.

The line to be cut may be drawn in a straight line along each side of the rectangle, or may be drawn in a specific shape on a portion of the display panel area as shown in FIG. 5 . The reason why the lower side of the display panel area is drawn as shown in FIG. 5 is that a specific device (eg, an IC) or a component (eg, a conductive part) may be positioned only on both sides of the lower part of the panel.

6 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment of the present specification.

The manufacturing method may be performed by manufacturing equipment of a display device. In addition, the display device has the characteristics described with reference to FIGS. 2 to 5 .

First, on one surface of the support substrate on which the plurality of unit display panel areas are disposed, the step of patterning the area between the cut lines of each unit panel with a light non-transmissive material ( S610 ) is performed.

Next, bonding the first surface of the mother substrate made of a flexible material to the patterning surface of the support substrate ( S620 ) is performed. The step S620 may include coating a plastic film on one surface of the patterned support substrate. In this case, the material of the parent substrate may be polyimide, and the support substrate may be a glass substrate.

Next, laminating a color filter layer on the second surface of the mother substrate for each area of the unit display panel ( S630 ) is performed.

Next, a step (S640) of scribing a cut line along the boundary line of the unit display panel is performed. The step S640 may be a step of drawing a cut line as much as the depth of the parent substrate along the outer boundary of the region where the color filter layer is formed.

Thereafter, a step (S650) of separating the support substrate and the mother substrate by irradiating laser light to the entire area of the support substrate is performed.

The step S650 may include separating the region where the light non-transmissive material is patterned from the support substrate at the same time. That is, in step S650, the region on which the light non-transmissive material is patterned is continuously attached to the support substrate.

The above description and the accompanying drawings are merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains can combine the configuration within a range that does not depart from the essential characteristics of the present invention. , various modifications and variations such as separation, substitution and alteration will be possible. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

Claims (6)

patterning, on one surface of a support substrate on which a plurality of unit display panel areas are disposed, an area between the cut lines of each unit panel with a light non-transmissive material;
bonding a first surface of a mother substrate made of a flexible material to a patterning surface of the support substrate;
stacking a color filter layer on the second surface of the mother substrate for each area of the unit display panel;
scribing a cut line along a boundary line of the unit display panel;
and separating the support substrate from the mother substrate by irradiating laser light to the entire area of the support substrate. According to claim 1,
The step of bonding the mother substrate to one surface of the support substrate comprises:
and coating the mother substrate made of the flexible material on one surface of the patterned support substrate in the form of a plastic film. According to claim 1,
The step of drawing the cut line is,
and drawing a line to be cut as much as the depth of the parent substrate along an outer boundary of the region where the color filter layer is formed. According to claim 1,
The material of the parent substrate is polyimide,
The support substrate is a method of manufacturing a display device, characterized in that the glass substrate. According to claim 1,
In the step of separating the support substrate and the parent substrate,
The method of claim 1 , wherein the light non-transmissive material patterned in a region between the cut lines is continuously attached to the support substrate. According to claim 1,
Separating the support substrate and the parent substrate comprises:
and separating the light non-transmissive material patterned in the region between the cut lines and the support substrate from the mother substrate at the same time.

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