JP6833385B2 - Display device manufacturing method and manufacturing device - Google Patents

Description

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

In recent years, an organic EL display including an organic light emitting diode (OLED), which is an organic EL element utilizing the organic electroluminescence (organic EL) phenomenon, has been developed. Since the organic EL display is self-luminous, it does not require a backlight unlike a conventional liquid crystal display (LCD), and it is easy to realize a thin display. In addition, OLED has the advantages of low power consumption, high contrast, and high response speed. However, since OLED uses an organic material for the light emitting layer, it deteriorates when exposed to water or oxygen, and malfunctions such as a decrease in brightness and inability to emit light occur. Therefore, there is a demand for a technique for suppressing deterioration of the light emitting layer of the OLED.

In the technique described in Patent Document 1, the first substrate on which the OLED is formed and the second substrate facing the OLED are fixed by an adhesive arranged so as to surround the OLED. A desiccant is arranged in the space partitioned by the first substrate, the second substrate, and the adhesive to suppress deterioration of the OLED due to water.

Japanese Unexamined Patent Publication No. 2012-28265

In Patent Document 1, since the adhesive used for fixing the substrates to each other is an ultraviolet curable resin or a thermosetting resin, the barrier property against water and oxygen is lower than that of a metal or an inorganic compound. Therefore, even if the desiccant is arranged in the vicinity of the OLED, it is not possible to sufficiently suppress the arrival of water and oxygen at the OLED, and the deterioration of the light emitting layer of the OLED tends to proceed. In the technique described in Patent Document 1, in order to reduce water and oxygen that pass through the adhesive and reach the OLED, it is necessary to widen the width of the adhesive and lengthen the invasion route of water and oxygen. In this case, the distance from the end of the adhesive to the OLED is increased to, for example, about several mm, which hinders the narrowing of the frame of the display.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a manufacturing device and a manufacturing method of a display device capable of reducing water and oxygen reaching the OLED.

A first aspect of the present invention is a method for manufacturing a display device including a first substrate having an organic light emitting diode layer and a second substrate facing the first substrate, wherein the organic light emitting diode layer is used. The step of bringing the first protrusion formed on the first substrate and the second protrusion formed on the second substrate so as to surround each other so as to face each other was brought into contact with the step. It has a step of joining the first protrusion and the second protrusion by applying a load to the first protrusion and the second protrusion and applying vibration.

A second aspect of the present invention is a display device manufacturing apparatus, which comprises a first substrate having an organic light emitting diode layer, a support base on which a second substrate facing the first substrate is placed, and a support base. The first protrusion formed on the first substrate so as to surround the organic light emitting diode layer and the second protrusion formed on the second substrate are in contact with each other facing each other. By applying vibration to the fixing portion to which the load is applied, the first protrusion and the second protrusion to which the load is applied by the fixing portion, the first protrusion and the second protrusion are applied. It has a vibration generating part that joins the protrusions of the above.

According to the present invention, a first substrate having an OLED and a second substrate facing the OLED are joined by applying vibration to the protrusions provided on the first substrate and the second substrate, respectively. .. The protrusions are provided so as to surround the display area and are firmly joined by vibration, so that water and oxygen reaching the OLED can be reduced.

It is a top view and sectional view of the display device which concerns on 1st Embodiment. It is a side view of the manufacturing apparatus of the display apparatus which concerns on 1st Embodiment. It is sectional drawing of the display device which concerns on 1st Embodiment. It is a figure which shows the flowchart of the joining method which concerns on 1st Embodiment. It is sectional drawing of the display device which concerns on 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the respective embodiments. In the drawings described below, those having the same function are designated by the same reference numerals, and the repeated description thereof may be omitted.

(First Embodiment)
FIG. 1A is a top view of the display device 100 according to the present embodiment. FIG. 1B is a cross-sectional view of the display device 100 as viewed from line AA of FIG. 1A. The display device 100 includes an OLED substrate 110 (first substrate) including an organic light emitting diode (OLED) and a sealing substrate 120 (second substrate). The size and composition ratio of each part included in the display device 100 shown in FIGS. 1A and 1B do not reflect the actual configuration, and may be arbitrarily designed according to the actual mounting method. The display device 100 according to the present embodiment may be either a top emission type that extracts light from the sealing substrate 120 side or a bottom emission type that extracts light from the OLED substrate 110 side.

The OLED substrate 110 and the sealing substrate 120 are rectangular flat plates arranged parallel to each other, and are fixed to each other by a joint 130. The OLED substrate 110 and the sealing substrate 120 are not limited to a rectangular flat plate, and may have any shape such as a circular shape or a polygonal shape, and may be a curved or bent plate.

The sealing substrate 120 is a substrate made of an inorganic substance such as quartz, glass, silicon, or metal, or a resin such as polycarbonate, polyethylene terephthalate, or polyimide. When the display device 100 is a top emission type, the sealing substrate 120 is made of a material that transmits light.

The OLED substrate 110 includes a multilayer barrier layer 112, a thin film transistor layer (TFT layer) 113, an organic light emitting diode layer (OLED layer) 114, and a high barrier layer 115 on the substrate 111. The substrate 111 is a substrate made of an inorganic substance such as quartz, glass, silicon, or metal, or a resin such as polycarbonate, polyethylene terephthalate, or polyimide. When the display device 100 is a bottom emission type, the substrate 111 is made of a material that transmits light.

The TFT layer 113 includes a thin film transistor (TFT) that controls the voltage supply to the OLED layer 114. The TFT may be either p-type or n-type and has a well-known configuration including a semiconductor layer and electrodes. The semiconductor layer of the TFT is formed using, for example, at least one material of amorphous silicon, polysilicon, and an oxide. The TFT supplies a voltage to the OLED layer 114 when a predetermined voltage is applied from a control device (not shown) via an electrode. The number and arrangement of TFTs included in the TFT layer 113 are arbitrarily designed according to the configuration of the display device 100. In particular, when the display device 100 is a bottom emission type, the electrode included in the TFT layer 113 is made of a conductive material that transmits light such as indium tin oxide (ITO).

The OLED layer 114 is a light emitting layer and includes an OLED (that is, an organic EL element) that emits light in response to a voltage supplied from the TFT layer 113. The OLED has a well-known configuration including an organic light emitting layer and electrodes. The organic light emitting layer is formed by using, for example, at least one of a dye-based material, a metal complex-based material, and a polymer-based material. The number and arrangement of OLEDs included in the OLED layer 114 are arbitrarily designed according to the configuration of the display device 100. In particular, when the display device 100 is a top emission type, the electrode included in the OLED layer 114 is made of a conductive material that transmits light such as indium tin oxide (ITO).

The multi-layer barrier layer 112 has a structure in which two or more layers of a film composed of at least one of a metal, an inorganic compound, and a polymer having a barrier property against oxygen and water are laminated. The high barrier layer 115 includes a film composed of at least one of a metal, an inorganic compound and a polymer having a barrier property against oxygen and water. The multilayer barrier layer 112 covers the substrate 111 side of the TFT layer 113 and the OLED layer 114, and the high barrier layer 115 covers the sealing substrate 120 side of the TFT layer 113 and the OLED layer 114 and their end faces. With such a configuration, oxygen and water are suppressed from reaching the TFT layer 113 and the OLED layer 114.

A first protrusion 131 is formed on the high barrier layer 115. The first protrusion 131 is provided so as to go around the peripheral edge of the high barrier layer 115 along the surface of the high barrier layer 115 and surround the OLED layer 114. Further, a second protrusion 132 is formed on the sealing substrate 120. When viewed from the direction perpendicular to the OLED substrate 110 and the sealing substrate 120, the second protrusion 132 has the same size and shape as the first protrusion 131. Therefore, when the surface of the OLED substrate 110 on the side of the first protrusion 131 and the surface of the sealing substrate 120 on the side of the second protrusion 132 face each other and come close to each other, the first protrusion 131 and the second protrusion 132 are brought close to each other. Completely overlap each other. The joint 130 is formed by integrating the first protrusion 131 and the second protrusion 132 in a state where the first protrusion 131 and the second protrusion 132 are overlapped with each other by using the joining method described later. Will be done.

The first protrusion 131 and the second protrusion 132 are made of metal. The metal constituting the first protrusion 131 and the second protrusion 132 is, for example, a simple substance or an alloy of Au, Ag, Cu, Mo, Al, Ni, and Sn.

The first protrusion 131 and the second protrusion 132 are thin film-shaped or rib-shaped, respectively. The first protrusion 131 and the second protrusion 132 each have a predetermined width capable of preventing the ingress of oxygen and water when the joint 130 is formed. Since the first protrusion 131 and the second protrusion 132 are made of a metal having excellent barrier properties against oxygen and water, the widths of the first protrusion 131 and the second protrusion 132 are wide. Even if the narrowness is larger than 0 μm and less than 10 μm, the effect of suppressing oxygen and water can be obtained. More preferably, the width of the first protrusion 131 and the second protrusion 132 is 10 μm or more and less than 100 μm.

Each of the first protrusion 131 and the second protrusion 132 has a predetermined height for providing a predetermined distance between the OLED substrate 110 and the sealing substrate 120. The heights of the first protrusion 131 and the second protrusion 132 are such that at least the OLED substrate 110 and the sealing substrate 120 do not come into contact with each other when the joint portion 130 is formed. The heights of the first protrusion 131 and the second protrusion 132 may be different from each other.

The first protrusion 131 and the second protrusion 132 may be formed by any method. The first protrusion 131 and the second protrusion 132 are formed by, for example, a vapor deposition method such as physical vapor deposition (PVD) or chemical vapor deposition (CVD), or a printing method such as screen printing using metal ink, inkjet, letterpress, or dispense. Formed by.

The configurations of the OLED substrate 110 and the sealing substrate 120 shown here are examples, and the components may be added or removed according to the actual configuration of the display device 100. In the present embodiment, the first protrusion 131 is provided on the high barrier layer 115, but is not limited to this, and may be provided so as to surround the outer periphery of the OLED layer 114. The first protrusion 131 may be provided, for example, on a substrate 111, a multi-layer barrier layer 112, or another layer (not shown).

The OLED substrate 110 and the sealing substrate 120 may be configured to be deformable in response to an external force. More specifically, at least one of the OLED substrate 110 and the sealing substrate 120 may be mounted as a deformable flexible substrate. In that case, the substrate 111 and the sealing substrate 120 of the OLED substrate 110 are configured by using a film made of a resin such as polyimide.

FIG. 2 is a side view of the manufacturing device 200 of the display device 100 according to the present embodiment. The manufacturing apparatus 200 includes a support base 210, a vibration generating portion 220, and a fixing portion 230. The support base 210 is a base on which the display device 100 being manufactured is placed. An arbitrary driving unit (not shown) such as a motor or a manipulator is provided on the support base 210, and the OLED substrate 110 and the sealing substrate 120 can be independently moved for alignment.

The vibration generating unit 220 is a device that generates vibration at a predetermined frequency to which the first protrusion 131 and the second protrusion 132 are joined. It is desirable that the frequency of vibration generated by the vibration generating unit 220 is in the ultrasonic region, that is, 20 kHz or more.

A fixing portion 230 is connected to the vibration generating portion 220 to apply a load to the display device 100 being manufactured and fix it. The fixing unit 230 includes a horn 231 that propagates vibration from the vibration generating unit 220 to the display device 100, and a head 232 that applies a load to the display device 100. The horn 231 is a director for efficiently propagating the vibration generated by the vibration generating unit 220 to the head 232. The head 232 comes into contact with the upper surface of the sealing substrate 120, and a load of a predetermined size is applied to the first protrusion 131 and the second protrusion 132 in the direction perpendicular to the OLED board 110 and the sealing board 120. Add. The magnitude of the load by the head 232 is at least a value at which the first protrusion 131 and the second protrusion 132 do not shift when vibration is applied to the first protrusion 131 and the second protrusion 132. .. The vibration direction of the vibration applied to the first protrusion 131 and the second protrusion 132 via the horn 231 and the head 232 is a direction parallel to the OLED board 110 and the sealing board 120.

When vibration of a predetermined frequency is generated from the vibration generating portion 220 while the display device 100 being manufactured is fixed by the fixing portion 230, the first protruding portion 131 and the second protruding portion 132 are joined and joined. Part 130 is formed. By generating vibration in the ultrasonic region, that is, a frequency of 20 kHz or more from the vibration generating unit 220, a large amount of energy can be applied to the first protrusion 131 and the second protrusion 132 to perform ultrasonic bonding. .. As a result, the interface between the first protrusion 131 and the second protrusion 132 is firmly joined, and the joint 130 capable of sufficiently suppressing the infiltration of oxygen and water is formed.

In ultrasonic bonding technology, by applying a load to the contact part of two metal materials and applying vibration, the unevenness of the interface of the contact part is smoothed and cleaned by vibration, and the bonding interfaces come into contact with each other to form atoms. Bonded at the atomic level by thinning force or the like. That is, since the bonding portion 130 formed by ultrasonic bonding is stronger than the conventional adhesive, even if the width is smaller than 10 μm, oxygen and water can be sufficiently prevented from entering. Therefore, it is not necessary to provide a surplus area around the OLED layer 114 to prevent the ingress of oxygen and water, and the display device 100 having a narrow frame can be realized.

Next, the joining method according to the present embodiment will be described with reference to FIGS. 3 (a) to 3 (c) and FIG. 3 (a) to 3 (c) are cross-sectional views of the display device 100 as viewed from the line AA of FIG. 1 (a) at each timing of the joining method according to the present embodiment. FIG. 4 is a diagram showing a flowchart of the joining method according to the present embodiment. The joining method shown in FIG. 4 is included in the manufacturing method of the display device 100. FIG. 3A is a cross-sectional view corresponding to step S11 in FIG. FIG. 3B is a cross-sectional view corresponding to step S12 in FIG. FIG. 3C is a cross-sectional view corresponding to step S13 in FIG.

First, the manufacturing apparatus 200 aligns the OLED substrate 110 and the sealing substrate 120 (step S11). The alignment is performed by moving at least one of the OLED substrate 110 and the sealing substrate 120 so that the first protrusion 131 and the second protrusion 132 face each other. For the above-mentioned positions, for example, the alignment marks formed on the OLED substrate 110 and the sealing substrate 120 are photographed by a camera or the like provided in the manufacturing apparatus 200 to acquire an image, and the marks are marked from the captured images. It can be obtained by calculating the coordinates. Processing such as moving the substrate for alignment, photographing marks, recognizing images, and calculating coordinates can be performed using well-known techniques. It should be noted that the alignment mark may not be explicitly provided, and the shape of the edge of the substrate or the like may be used to acquire the alignment information.

Next, the manufacturing apparatus 200 brings the OLED substrate 110 and the sealing substrate 120 close to each other, and brings the first protrusion 131 and the second protrusion 132 into contact with each other (step S12). The arrangement of the OLED substrate 110 and the sealing substrate 120 in steps S11 to S12 may be manually performed by the user.

Next, the manufacturing apparatus 200 applies a load of a predetermined size to the first protrusion 131 and the second protrusion 132 by using the fixing portion 230 (that is, the horn 231 and the head 232), and the vibration generating portion 220 causes the manufacturing apparatus 200 to apply a load of a predetermined size. The generated vibration of a predetermined frequency is applied to the first protrusion 131 and the second protrusion 132 via the fixing portion 230 (step S13). As a result, the first protrusion 131 and the second protrusion 132 are joined by vibration to form the joint 130.

At the time of joining in step S13, the first protrusion 131 and the second protrusion 132 may be heated to a temperature higher than room temperature. By raising the temperature of the contact portion between the first protrusion 131 and the second protrusion 132 to a high temperature, the formation of a joint by applying vibration or the like can be further promoted. However, heating is not essential if sufficient bonding strength can be obtained without heating. In the above-mentioned heating, both the first protrusion 131 and the second protrusion 132 may be heated, or only one of them may be heated. Further, the entire OLED substrate 110 and the sealing substrate 120 may be heated, or only the vicinity of the first protrusion 131 and the second protrusion 132 may be locally heated.

The joining in step S13 may be performed in two steps, a temporary joining and a main joining. In the temporary joining, at least a part of the first protrusion 131 and the second protrusion 132 is joined in a short time prior to the main joining, so that the aligned positions are displaced before the main joining is performed. It is a process to prevent it. This joining is a step for making the joining state more reliable by performing the joining over a relatively long time. In the manufacturing apparatus 200, by separately mounting the portion for performing the alignment and temporary joining and the portion for performing the main joining, the alignment and the temporary joining and the main joining can be performed in parallel, so that the processing speed is high. Can be transformed.

Since the technique described in Patent Document 1 described above has a structure in which the OLED is surrounded by a resin adhesive, it is necessary to increase the width of the adhesive in order to sufficiently suppress the invasion of oxygen and water. Therefore, the technique described in Patent Document 1 does not have a sufficient effect of suppressing the intrusion of oxygen and water into the OLED, and it is difficult to realize a display device having a narrow frame. On the other hand, in the manufacturing method according to the present embodiment, since the first protrusion 131 and the second protrusion 132 formed by using metal are joined by vibration (particularly ultrasonic vibration), the OLED layer 114 It forms a strong joint 130 that surrounds it. With such a configuration, deterioration of the OLED layer 114 due to infiltration of oxygen and water can be suppressed more effectively than before. Further, since the width of the joint portion 130 can be reduced, the display device 100 having a narrow frame can be realized.

(Second Embodiment)
In the display device 100 according to the first embodiment, the joint portion 130 is formed on the high barrier layer 115 that covers the OLED layer 114. On the other hand, in the display device 300 according to the present embodiment, the high barrier layer 115 is omitted, and the joint portion 130 is directly provided on the substrate 111. The manufacturing method of the display device 300 is the same as that of the first embodiment.

FIG. 5 is a cross-sectional view of the display device 300 according to the present embodiment. The cross-sectional view of FIG. 5 is a view of the display device 300 from the line AA of FIG. 1 (a). The display device 300 includes the OLED substrate 110 and the sealing substrate 120 as in the first embodiment, but only the configuration of the OLED substrate 110 is different from that of the first embodiment.

The OLED substrate 110 includes a TFT layer 113 and an OLED layer 114 on the substrate 111. That is, the multi-layer barrier layer 112 and the high barrier layer 115 are omitted from the configuration of the display device 100 of the first embodiment. Further, the first protrusion 131 is directly formed on the substrate 111. The first protrusion 131 is provided so as to go around the peripheral edge of the substrate 111 along the surface of the substrate 111 and surround the OLED layer 114. Further, a second protrusion 132 is formed on the sealing substrate 120. When viewed from the direction perpendicular to the OLED substrate 110 and the sealing substrate 120, the second protrusion 132 has the same size and shape as the first protrusion 131. When the surface of the OLED substrate 110 on the side of the first protrusion 131 and the surface of the sealing substrate 120 on the side of the second protrusion 132 face each other and come close to each other, the first protrusion 131 and the second protrusion 132 become It completely overlaps with each other. The first protrusion 131 and the second protrusion 132 form a joint 130 by ultrasonic bonding as in the first embodiment.

In the present embodiment, the heights of the first protrusion 131 and the second protrusion 132 are at least the OLED layer 114 when the first protrusion 131 and the second protrusion 132 form the joint 130. The height is such that it does not come into contact with the sealing substrate 120. The heights of the first protrusion 131 and the second protrusion 132 may be different from each other.

In this embodiment, the outside of the end face of the joint 130 is surrounded by a joint 130 formed by ultrasonic bonding. Therefore, since oxygen and water can be suppressed from entering the space partitioned by the OLED substrate 110, the sealing substrate 120, and the joint portion 130, the multilayer barrier layer 112 and the high barrier layer 115 are omitted. Even so, deterioration of the OLED layer 114 can be effectively suppressed.

The present invention is not limited to the above-described embodiment, and can be appropriately modified without departing from the spirit of the present invention.

100, 300 Display device 110 OLED board 114 OLED layer 120 Encapsulation board 131 First protrusion 132 Second protrusion 200 Manufacturing equipment 210 Support base 220 Vibration generator 230 Fixed part

Claims (7)

A method of manufacturing a Viewing device,
The step of forming the organic light emitting diode layer on the flat first substrate,
A step of forming a barrier layer having a flat upper surface and covering the organic light emitting diode layer,
Forming a first protrusion on said barrier layer so as to surround the organic light emitting diode layer,
A step that form a second protrusion on the flat second substrate,
A step of arranging the first substrate and the second substrate so that the first protrusion and the second protrusion come into contact with each other.
A step of joining the first protrusion and the second protrusion by applying a load to the contacted first protrusion and the second protrusion and applying vibration.
Have a,
The first protrusion and the second protrusion contain metal and contain metal.
The load is applied in the direction perpendicular to the first substrate and the second substrate.
The joining step includes a step of applying vibration in a direction parallel to the first substrate and the second substrate.
By purifying the interface between the first protrusion and the contact portion between the second protrusions and flattening the unevenness of the interface by the vibration, the first protrusion and the second protrusion To join by interatomic attraction,
How to manufacture a display device. The method for manufacturing a display device according to claim 1, wherein the vibration is ultrasonic vibration. The method for manufacturing a display device according to claim 2, wherein the frequency of the vibration is 20 kHz or more. The method for manufacturing a display device according to any one of claims 1 to 3, wherein the first protrusion and the second protrusion have the same size and shape. The method for manufacturing a display device according to claim 1 , wherein the first protrusion and the second protrusion contain a simple substance or an alloy of Au, Ag, Cu, Mo, Al, Ni, Sn. .. The method for manufacturing a display device according to any one of claims 1 to 5 , wherein the width of the first protrusion and the width of the second protrusion is larger than 0 μm and less than 10 μm. A first substrate having an organic light emitting diode layer, a support base on which a second substrate facing the first substrate is placed, and a support base.
The first protrusion formed on the first substrate so as to surround the organic light emitting diode layer and the second protrusion formed on the second substrate are in contact with each other facing each other. A fixed part that lets you apply a load,
A vibration generating portion that joins the first protrusion and the second protrusion by applying vibration to the first protrusion and the second protrusion to which the load is applied by the fixing portion. When,
Have a,
The first protrusion and the second protrusion contain metal and contain metal.
The fixing portion includes a horn and a head that applies the load to the first protrusion and the second protrusion in a direction perpendicular to the first substrate and the second substrate.
One end of the horn is connected to the head, and the other end of the horn extends in a direction parallel to the surface of the support and is connected to the vibration generating portion.
The vibration is applied to the head via the horn and is in a direction parallel to the first substrate and the second substrate.
By purifying the interface between the first protrusion and the contact portion between the second protrusions and flattening the unevenness of the interface by the vibration, the first protrusion and the second protrusion To join by interatomic attraction,
Display device manufacturing equipment.

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