KR20220006365A - Display device using semiconductor light emitting elemetn - Google Patents

Abstract

The present invention provides a display device using a semiconductor light emitting element. The display device includes a frame, a plurality of display modules arranged in a grid on the frame to output an image signal, and a coating layer coated to connect the front surfaces of the plurality of display modules. According to the present invention, it is possible to prevent optical loss due to a gap formed between the tiled display modules.

Description

Display device using semiconductor light emitting device {DISPLAY DEVICE USING SEMICONDUCTOR LIGHT EMITTING ELEMETN}

The present invention relates to a display device using a semiconductor light emitting device. Here, the semiconductor light emitting device may correspond to micro LEDs (Light Emitting Diodes). The present invention relates to a display device capable of being enlarged and standardized.

Recently, in the field of display technology, a display device having excellent characteristics such as thinness and flexibility has been developed. Currently, commercialized major displays are represented by LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diodes).

However, in the case of LCD, there are problems in that the response time is not fast and it is difficult to implement flexible, and in the case of OLED, there are problems in that the lifespan is short and the mass production yield is not good.

On the other hand, a light emitting diode (Light Emitting Diode: LED) is a semiconductor light emitting device well known for converting current into light. It has been used as a light source for display images of electronic devices including information and communication devices. Accordingly, a method for solving the above-described problems by implementing a display device using the semiconductor light emitting device may be proposed. The semiconductor light emitting device has various advantages, such as a long lifespan, low power consumption, excellent initial driving characteristics, and high vibration resistance, compared to a filament-based light emitting device.

In order to implement a display device using such semiconductor light emitting devices, a very large number of semiconductor light emitting devices are required. Therefore, in consideration of the manufacturing cost, the size of the individual semiconductor light emitting devices should be miniaturized so as to increase the number of semiconductor light emitting devices that can be produced on a substrate of the same area.

As the semiconductor light emitting device is miniaturized, there is a problem in that the production yield of the display device is reduced. In particular, in the case of a large display device, there is a problem in that the yield is significantly reduced. In order to solve this problem, a large display is implemented by combining a display module.

However, when a large display is implemented by assembling a display module, there is a problem that a gap occurs between display modules due to a manufacturing tolerance and a problem that a step difference between the display modules occurs physically.

An object of the present invention is to provide a display device using a semiconductor light emitting device.

An object of an embodiment of the present invention is to implement a large display by tiling a display module.

An object of an embodiment of the present invention is to minimize a step difference between tiled display modules.

It is an object of an embodiment of the present invention to prevent optical loss due to a gap formed between tiled display modules.

Furthermore, another object of an embodiment of the present invention is to solve various problems not mentioned herein. Those skilled in the art can understand through the whole spirit of the specification and drawings.

A display device using a semiconductor light emitting device for achieving the above object includes a frame, a plurality of display modules arranged in a grid on the frame to output image signals, and a coating layer coated to connect the front surfaces of the plurality of display modules can do.

In addition, according to an embodiment, the coating layer may be cured after coating the front surfaces of the plurality of display modules with a liquid to offset a step difference between the front surfaces of the plurality of display modules.

In addition, according to an embodiment, in the coating layer, the cohesive force of the material in the liquid phase may be greater than the adhesion to the side surface of the display module and the weight of the material.

Also, according to an embodiment, the display device using the semiconductor light emitting device may further include a sealing member for sealing gaps formed between the plurality of display modules in a rear direction.

Also, according to an embodiment, the sealing member may be provided along a grid pattern formed by the plurality of display modules on the frame.

Also, according to an embodiment, the coating layer may include a protrusion introduced into a gap formed between the plurality of display modules.

Also, according to an embodiment, the protrusion may include a curved portion convex in a gap direction formed between the plurality of display modules.

Also, according to an embodiment, the coating layer may include at least one of an epoxy resin adhesive, a silicone resin adhesive, or a tape having adhesive strength.

Also, according to an embodiment, the display module may include a base substrate including a wiring circuit, and a plurality of semiconductor light emitting devices provided on the base substrate and connected to the wiring circuit.

Additionally, a method of manufacturing a display device using a semiconductor light emitting device for achieving the above object includes arranging a plurality of display modules on a frame, coating a liquid coating layer so that the front surfaces of the plurality of display modules are connected , and curing the coating layer in a flat state in which the step difference between the front surfaces of the plurality of display modules is offset.

In addition, according to an embodiment, in the coating layer, the cohesive force of the material in the liquid phase may be greater than the adhesion to the side surface of the display module and the weight of the material.

Also, according to an embodiment, the method of manufacturing a display device using a semiconductor light emitting device may further include applying a sealing member on the frame along an edge of a region where the display module is located.

Also, according to an embodiment, the sealing member may seal gaps formed between the plurality of display modules in a rear direction in a state in which the plurality of display modules are arranged in the frame.

According to an embodiment of the present invention, a display device using a semiconductor light emitting device can be provided.

According to an embodiment of the present invention, a large display may be implemented by tiling the display module.

According to an embodiment of the present invention, a step difference between tiled display modules may be offset.

According to an embodiment of the present invention, it is possible to prevent optical loss due to a gap formed between tiled display modules.

Furthermore, according to another embodiment of the present invention, there are additional technical effects not mentioned herein. Those skilled in the art can understand through the whole spirit of the specification and drawings.

1 is a conceptual diagram illustrating an embodiment of a display device using a semiconductor light emitting device of the present invention.
FIG. 2 is a partially enlarged view of part A of FIG. 1 .
3A and 3B are cross-sectional views taken along lines BB and CC of FIG. 2 .
4 is a conceptual diagram illustrating the flip-chip type semiconductor light emitting device of FIG. 3 .
5A to 5C are conceptual views illustrating various forms of implementing colors in relation to a flip-chip type semiconductor light emitting device.
6 is a cross-sectional view illustrating a method of manufacturing a display device using a semiconductor light emitting device of the present invention.
7 is a perspective view illustrating another embodiment of a display device using a semiconductor light emitting device of the present invention.
FIG. 8 is a cross-sectional view taken along line DD of FIG. 7 .
9 is a conceptual diagram illustrating the vertical semiconductor light emitting device of FIG. 8 .
10 is a perspective view of a display device using a semiconductor light emitting device manufactured by tiling a display module.
11 is an enlarged view of part A of FIG. 10 .
12 is a conceptual diagram for explaining a coating layer that offsets a step difference occurring between display modules.
13 is an enlarged view of part B of FIG. 12 .
14 is a conceptual diagram for explaining a coating layer that prevents optical loss occurring in a gap formed between display modules.
15 is a conceptual diagram illustrating a method of manufacturing a display device using a semiconductor light emitting device according to an exemplary embodiment.

Hereinafter, the embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but the same or similar components are assigned the same reference numbers regardless of reference numerals, and redundant description thereof will be omitted. The suffixes "module" and "part" for components used in the following description are given or mixed in consideration of only the ease of writing the specification, and do not have distinct meanings or roles by themselves. In addition, in describing the embodiments disclosed in the present specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in the present specification, the detailed description thereof will be omitted. In addition, it should be noted that the accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and should not be construed as limiting the technical spirit disclosed herein by the accompanying drawings.

Furthermore, although each drawing is described for convenience of description, it is also within the scope of the present invention that those skilled in the art implement other embodiments by combining at least two or more drawings.

It is also understood that when an element, such as a layer, region, or substrate, is referred to as being “on” another component, it may be directly present on the other element or intervening elements in between. There will be.

The display device described herein is a concept including all display devices that display information in a unit pixel or a set of unit pixels. Therefore, it can be applied not only to the finished product but also to parts. For example, a panel corresponding to a part of a digital TV also independently corresponds to a display device in the present specification. The finished products include mobile phones, smart phones, laptop computers, digital broadcasting terminals, personal digital assistants (PDA), portable multimedia players (PMPs), navigation systems, slate PCs, Tablet PCs, Ultra Books, digital TVs, desktop computers, etc. may be included.

However, it will be readily apparent to those skilled in the art that the configuration according to the embodiment described herein may be applied to a display capable device even in a new product form to be developed later.

In addition, the semiconductor light emitting device mentioned in this specification is a concept including an LED, a micro LED, and the like, and may be used interchangeably.

1 is a conceptual diagram illustrating an embodiment of a display device using a semiconductor light emitting device of the present invention.

1 , information processed by a controller (not shown) of the display apparatus 100 may be displayed using a flexible display.

The flexible display includes, for example, a display that can be bent, bent, or twisted, or folded or rolled by an external force.

Furthermore, the flexible display may be, for example, a display manufactured on a thin and flexible substrate that can be bent, bent, folded, or rolled like paper while maintaining the display characteristics of a conventional flat panel display.

In a state in which the flexible display is not bent (eg, a state having an infinite radius of curvature, hereinafter referred to as a first state), the display area of the flexible display becomes a flat surface. In a state bent by an external force in the first state (eg, a state having a finite radius of curvature, hereinafter referred to as a second state), the display area may be a curved surface. 1 , the information displayed in the second state may be visual information output on a curved surface. Such visual information is implemented by independently controlling the emission of sub-pixels arranged in a matrix form. The unit pixel means, for example, a minimum unit for realizing one color.

The unit pixel of the flexible display may be implemented by a semiconductor light emitting device. In the present invention, a light emitting diode (LED) is exemplified as a type of a semiconductor light emitting device that converts current into light. The light emitting diode is formed to have a small size, so that it can serve as a unit pixel even in the second state.

A flexible display implemented using the light emitting diode will be described in more detail with reference to the drawings below.

FIG. 2 is a partially enlarged view of part A of FIG. 1 .

3A and 3B are cross-sectional views taken along lines B-B and C-C in FIG. 2 .

4 is a conceptual diagram illustrating the flip-chip type semiconductor light emitting device of FIG. 3 .

5A to 5C are conceptual views illustrating various forms of implementing colors in relation to a flip-chip type semiconductor light emitting device.

As shown in FIGS. 2, 3A, and 3B , as the display device 100 using a semiconductor light emitting device, the display device 100 using a passive matrix (PM) type semiconductor light emitting device is exemplified. However, the examples described below are also applicable to an active matrix (AM) type semiconductor light emitting device.

The display device 100 shown in FIG. 1 includes a substrate 110 , a first electrode 120 , a conductive adhesive layer 130 , a second electrode 140 , and at least one semiconductor light emitting device as shown in FIG. 2 . (150).

The substrate 110 may be a flexible substrate. For example, to implement a flexible display device, the substrate 110 may include glass or polyimide (PI). In addition, any material such as polyethylene naphthalate (PEN) or polyethylene terephthalate (PET) may be used as long as it has insulating properties and is flexible. In addition, the substrate 110 may be made of either a transparent material or an opaque material.

The substrate 110 may be a wiring substrate on which the first electrode 120 is disposed, and thus the first electrode 120 may be located on the substrate 110 .

As shown in FIG. 3A , the insulating layer 160 may be disposed on the substrate 110 on which the first electrode 120 is positioned, and the auxiliary electrode 170 may be positioned on the insulating layer 160 . In this case, a state in which the insulating layer 160 is laminated on the substrate 110 may be a single wiring board. More specifically, the insulating layer 160 is made of an insulating and flexible material such as polyimide (PI, Polyimide), PET, PEN, etc., and is integrally formed with the substrate 110 to form a single substrate.

The auxiliary electrode 170 is an electrode that electrically connects the first electrode 120 and the semiconductor light emitting device 150 , is located on the insulating layer 160 , and is disposed to correspond to the position of the first electrode 120 . For example, the auxiliary electrode 170 may have a dot shape and may be electrically connected to the first electrode 120 by an electrode hole 171 penetrating the insulating layer 160 . The electrode hole 171 may be formed by filling the via hole with a conductive material.

2 or 3A, the conductive adhesive layer 130 is formed on one surface of the insulating layer 160, but the present invention is not necessarily limited thereto. For example, a layer performing a specific function is formed between the insulating layer 160 and the conductive adhesive layer 130 , or the conductive adhesive layer 130 is disposed on the substrate 110 without the insulating layer 160 . is also possible In a structure in which the conductive adhesive layer 130 is disposed on the substrate 110 , the conductive adhesive layer 130 may serve as an insulating layer.

The conductive adhesive layer 130 may be a layer having adhesiveness and conductivity, and for this purpose, a material having conductivity and a material having adhesiveness may be mixed in the conductive adhesive layer 130 . In addition, the conductive adhesive layer 130 has flexibility, thereby enabling a flexible function in the display device.

For this example, the conductive adhesive layer 130 may be an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing conductive particles, or the like. The conductive adhesive layer 130 may be configured as a layer that allows electrical interconnection in the Z direction passing through the thickness, but has electrical insulation in the horizontal X-Y direction. Accordingly, the conductive adhesive layer 130 may be referred to as a Z-axis conductive layer (however, hereinafter referred to as a 'conductive adhesive layer').

The anisotropic conductive film is a film in which an anisotropic conductive medium is mixed with an insulating base member, and when heat and pressure are applied, only a specific portion has conductivity by the anisotropic conductive medium. Hereinafter, it will be described that heat and pressure are applied to the anisotropic conductive film, but other methods may be applied in order for the anisotropic conductive film to have partial conductivity. The other method described above may be, for example, only one of the heat and pressure is applied or UV curing.

In addition, the anisotropic conductive medium may be, for example, conductive balls or conductive particles. For example, the anisotropic conductive film is a film in which conductive balls are mixed with an insulating base member, and when heat and pressure are applied, only a specific portion has conductivity by the conductive balls. The anisotropic conductive film may be in a state in which a core of a conductive material is covered with a plurality of particles covered by an insulating film made of a polymer material. . At this time, the shape of the core may be deformed to form a layer in contact with each other in the thickness direction of the film. As a more specific example, heat and pressure are applied as a whole to the anisotropic conductive film, and an electrical connection in the Z-axis direction is partially formed by the height difference of an object adhered by the anisotropic conductive film.

As another example, the anisotropic conductive film may be in a state in which an insulating core contains a plurality of particles coated with a conductive material. In this case, the conductive material is deformed (compressed) in the portion to which heat and pressure are applied, so that it has conductivity in the thickness direction of the film. As another example, a form in which the conductive material penetrates the insulating base member in the Z-axis direction to have conductivity in the thickness direction of the film is also possible. In this case, the conductive material may have a pointed end.

The anisotropic conductive film may be a fixed array anisotropic conductive film (ACF) in which conductive balls are inserted into one surface of the insulating base member. More specifically, the insulating base member is formed of a material having an adhesive property, the conductive balls are intensively disposed on the bottom portion of the insulating base member, and when heat and pressure are applied to the base member, the conductive balls are deformed together. It has conductivity in the vertical direction.

However, the present invention is not necessarily limited thereto, and the anisotropic conductive film has a form in which conductive balls are randomly mixed in an insulating base member, or is composed of a plurality of layers and conductive balls are arranged on one layer (double- ACF) are all possible.

The anisotropic conductive paste is a combination of a paste and a conductive ball, and may be a paste in which a conductive ball is mixed with an insulating and adhesive base material. Also, a solution containing conductive particles may be a solution containing conductive particles or nanoparticles.

Referring back to FIG. 3A , the second electrode 140 is positioned on the insulating layer 160 to be spaced apart from the auxiliary electrode 170 . That is, the conductive adhesive layer 130 is disposed on the insulating layer 160 in which the auxiliary electrode 170 and the second electrode 140 are located.

After the conductive adhesive layer 130 is formed in the state where the auxiliary electrode 170 and the second electrode 140 are positioned on the insulating layer 160, the semiconductor light emitting device 150 is connected in a flip-chip form by applying heat and pressure. In this case, the semiconductor light emitting device 150 is electrically connected to the first electrode 120 and the second electrode 140 .

Referring to FIG. 4 , the semiconductor light emitting device may be a flip chip type light emitting device.

For example, the semiconductor light emitting device includes a p-type electrode 156 , a p-type semiconductor layer 155 on which the p-type electrode 156 is formed, an active layer 154 formed on the p-type semiconductor layer 155 , an active layer ( It includes an n-type semiconductor layer 153 formed on the 154 , and an n-type electrode 152 spaced apart from the p-type electrode 156 in the horizontal direction on the n-type semiconductor layer 153 . In this case, the p-type electrode 156 may be electrically connected to the auxiliary electrode 170 and the conductive adhesive layer 130 as shown in FIG. 3 , and the n-type electrode 152 is electrically connected to the second electrode 140 . can be connected to

Referring back to FIGS. 2, 3A, and 3B , the auxiliary electrode 170 is formed to be elongated in one direction, so that one auxiliary electrode may be electrically connected to the plurality of semiconductor light emitting devices 150 . For example, p-type electrodes of left and right semiconductor light emitting devices with respect to the auxiliary electrode may be electrically connected to one auxiliary electrode.

More specifically, the semiconductor light emitting device 150 is press-fitted into the conductive adhesive layer 130 by heat and pressure, and through this, a portion between the p-type electrode 156 and the auxiliary electrode 170 of the semiconductor light emitting device 150 . And, only the portion between the n-type electrode 152 and the second electrode 140 of the semiconductor light emitting device 150 has conductivity, and there is no press-fitting of the semiconductor light emitting device in the remaining portion, so that it does not have conductivity. As described above, the conductive adhesive layer 130 not only interconnects the semiconductor light emitting device 150 and the auxiliary electrode 170 and between the semiconductor light emitting device 150 and the second electrode 140 , but also forms an electrical connection.

In addition, the plurality of semiconductor light emitting devices 150 constitute a light emitting device array, and the phosphor layer 180 is formed on the light emitting device array.

The light emitting device array may include a plurality of semiconductor light emitting devices having different luminance values. Each semiconductor light emitting device 150 constitutes a unit pixel and is electrically connected to the first electrode 120 . For example, there may be a plurality of first electrodes 120 , the semiconductor light emitting devices may be arranged in, for example, several columns, and the semiconductor light emitting devices in each column may be electrically connected to any one of the plurality of first electrodes.

In addition, since the semiconductor light emitting devices are connected in a flip-chip form, semiconductor light emitting devices grown on a transparent dielectric substrate can be used. In addition, the semiconductor light emitting devices may be, for example, nitride semiconductor light emitting devices. Since the semiconductor light emitting device 150 has excellent luminance, individual unit pixels can be configured even with a small size.

As shown in FIG. 3 , a barrier rib 190 may be formed between the semiconductor light emitting devices 150 . In this case, the partition wall 190 may serve to separate individual unit pixels from each other, and may be integrally formed with the conductive adhesive layer 130 . For example, by inserting the semiconductor light emitting device 150 into the anisotropic conductive film, the base member of the anisotropic conductive film may form the barrier rib.

In addition, when the base member of the anisotropic conductive film is black, the barrier rib 190 may have reflective properties and increase contrast even without a separate black insulator.

As another example, a reflective barrier rib may be separately provided as the barrier rib 190 . In this case, the barrier rib 190 may include a black or white insulator depending on the purpose of the display device. When the barrier ribs made of a white insulator are used, reflectivity may be increased, and when the barrier ribs made of a black insulator are used, it is possible to have reflective properties and increase contrast.

The phosphor layer 180 may be located on the outer surface of the semiconductor light emitting device 150 . For example, the semiconductor light emitting device 150 is a blue semiconductor light emitting device that emits blue (B) light, and the phosphor layer 180 functions to convert the blue (B) light into the color of the unit pixel. The phosphor layer 180 may be a red phosphor 181 or a green phosphor 182 constituting an individual pixel.

That is, a red phosphor 181 capable of converting blue light into red (R) light may be stacked on the blue semiconductor light emitting device at a position constituting the unit pixel of red color, and at a position constituting the unit pixel of green color, blue light A green phosphor 182 capable of converting blue light into green (G) light may be stacked on the semiconductor light emitting device. In addition, only the blue semiconductor light emitting device may be used alone in the portion constituting the blue unit pixel. In this case, unit pixels of red (R), green (G), and blue (B) may form one pixel. More specifically, a phosphor of one color may be stacked along each line of the first electrode 120 . Accordingly, one line in the first electrode 120 may be an electrode for controlling one color. That is, red (R), green (G), and blue (B) may be sequentially disposed along the second electrode 140 , thereby realizing a unit pixel.

However, the present invention is not necessarily limited thereto, and instead of the phosphor, the semiconductor light emitting device 150 and the quantum dot (QD) are combined to implement unit pixels of red (R), green (G), and blue (B). have.

In addition, a black matrix 191 may be disposed between each of the phosphor layers to improve contrast. That is, the black matrix 191 may improve contrast of light and dark.

However, the present invention is not necessarily limited thereto, and other structures for implementing blue, red, and green colors may be applied.

Referring to FIG. 5A , each semiconductor light emitting device 150 has gallium nitride (GaN) as a main material, and indium (In) and/or aluminum (Al) are added together to emit a variety of light including blue. It may be implemented as a light emitting device.

In this case, the semiconductor light emitting device 150 may be a red, green, and blue semiconductor light emitting device to form a sub-pixel, respectively. For example, red, green, and blue semiconductor light emitting devices R, G, and B are alternately arranged, and unit pixels of red, green, and blue colors by the red, green and blue semiconductor light emitting devices The pixels form one pixel, through which a full-color display can be realized.

Referring to FIG. 5B , the semiconductor light emitting device 150a may include a white light emitting device W in which a yellow phosphor layer is provided for each individual device. In this case, a red phosphor layer 181 , a green phosphor layer 182 , and a blue phosphor layer 183 may be provided on the white light emitting device W to form a unit pixel. In addition, a unit pixel may be formed on the white light emitting device W by using a color filter in which red, green, and blue are repeated.

Referring to FIG. 5C , a structure in which a red phosphor layer 184 , a green phosphor layer 185 , and a blue phosphor layer 186 are provided on the ultraviolet light emitting device 150b is also possible. In this way, the semiconductor light emitting device can be used in the entire region not only for visible light but also for ultraviolet (UV) light, and can be extended to the form of a semiconductor light emitting device in which ultraviolet (UV) can be used as an excitation source of the upper phosphor. .

Referring back to this example, the semiconductor light emitting device is positioned on the conductive adhesive layer to constitute a unit pixel in the display device. Since the semiconductor light emitting device has excellent luminance, individual unit pixels can be configured even with a small size.

The size of the individual semiconductor light emitting device 150 may be, for example, a side length of 80 μm or less, and may be a rectangular or square device. In the case of a rectangle, the size may be 20 X 80 μm or less.

In addition, even when a square semiconductor light emitting device 150 having a side length of 10 μm is used as a unit pixel, sufficient brightness to form a display device appears.

Accordingly, if the size of the unit pixel is a rectangular pixel having one side of 600 μm and the other side of 300 μm, for example, the distance between the semiconductor light emitting devices is relatively large.

Accordingly, in this case, it is possible to implement a flexible display device having a high picture quality higher than or equal to HD picture quality.

The display device using the semiconductor light emitting device described above can be manufactured by a new type of manufacturing method. Hereinafter, the manufacturing method will be described with reference to FIG. 6 .

6 is a cross-sectional view illustrating a method of manufacturing a display device using a semiconductor light emitting device of the present invention.

As shown in FIG. 6 , first, a conductive adhesive layer 130 is formed on the insulating layer 160 on which the auxiliary electrode 170 and the second electrode 140 are positioned. An insulating layer 160 is stacked on a wiring board 110 , and a first electrode 120 , an auxiliary electrode 170 , and a second electrode 140 are disposed on the wiring board 110 . In this case, the first electrode 120 and the second electrode 140 may be disposed in a mutually orthogonal direction. In addition, in order to implement a flexible display device, the wiring board 110 and the insulating layer 160 may each include glass or polyimide (PI).

The conductive adhesive layer 130 may be implemented by, for example, an anisotropic conductive film, and for this purpose, the anisotropic conductive film may be applied to the substrate on which the insulating layer 160 is positioned.

Next, a temporary substrate 112 corresponding to the positions of the auxiliary electrode 170 and the second electrodes 140 and on which a plurality of semiconductor light emitting devices 150 constituting individual pixels are located is formed with the semiconductor light emitting device 150 . ) is disposed to face the auxiliary electrode 170 and the second electrode 140 .

In this case, the temporary substrate 112 is a growth substrate on which the semiconductor light emitting device 150 is grown, and may be a sapphire substrate or a silicon substrate.

When the semiconductor light emitting device is formed in units of wafers, the semiconductor light emitting device can be effectively used in a display device by having an interval and a size that can form a display device.

Then, the wiring board and the temporary board 112 are thermocompressed. For example, the wiring board and the temporary board 112 may be thermocompressed by applying an ACF press head. The wiring board and the temporary board 112 are bonded by the thermal compression. Due to the properties of the anisotropic conductive film having conductivity by thermal compression, only the portion between the semiconductor light emitting device 150 and the auxiliary electrode 170 and the second electrode 140 has conductivity, and through this, the electrodes and the semiconductor light emission. The device 150 may be electrically connected. At this time, the semiconductor light emitting device 150 is inserted into the anisotropic conductive film, and through this, a barrier rib may be formed between the semiconductor light emitting devices 150 .

Then, the temporary substrate 112 is removed. For example, the temporary substrate 112 may be removed using a laser lift-off (LLO) method or a chemical lift-off (CLO) method.

Finally, the temporary substrate 112 is removed to expose the semiconductor light emitting devices 150 to the outside. If necessary, a transparent insulating layer (not shown) may be formed by coating silicon oxide (SiOx) or the like on the wiring board to which the semiconductor light emitting device 150 is coupled.

In addition, the method may further include forming a phosphor layer on one surface of the semiconductor light emitting device 150 . For example, the semiconductor light emitting device 150 is a blue semiconductor light emitting device that emits blue (B) light, and a red or green phosphor for converting the blue (B) light into the color of a unit pixel is the blue semiconductor light emitting device. A layer may be formed on one surface of the device.

The manufacturing method or structure of the display device using the semiconductor light emitting device described above may be modified in various forms. As an example, a vertical semiconductor light emitting device may also be applied to the display device described above.

In addition, in the modification or embodiment described below, the same or similar reference numerals are assigned to the same or similar components as those of the preceding example, and the description is replaced with the first description.

7 is a perspective view showing another embodiment of a display device using a semiconductor light emitting device of the present invention, FIG. 8 is a cross-sectional view taken along line DD of FIG. 7, and FIG. 9 is a vertical type semiconductor light emitting device of FIG. It is a conceptual diagram.

Referring to the drawings, the display device may be a display device using a passive matrix (PM) type vertical semiconductor light emitting device.

The display device includes a substrate 210 , a first electrode 220 , a conductive adhesive layer 230 , a second electrode 240 , and at least one semiconductor light emitting device 250 .

The substrate 210 is a wiring substrate on which the first electrode 220 is disposed, and may include polyimide (PI) to implement a flexible display device. In addition, any material that has insulating properties and is flexible may be used.

The first electrode 220 is positioned on the substrate 210 and may be formed as a bar-shaped electrode long in one direction. The first electrode 220 may serve as a data electrode.

The conductive adhesive layer 230 is formed on the substrate 210 on which the first electrode 220 is positioned. Like a display device to which a flip chip type light emitting device is applied, the conductive adhesive layer 230 is an anisotropic conductive film (ACF), an anisotropic conductive paste, and a solution containing conductive particles. ), and so on. However, in this embodiment as well, a case in which the conductive adhesive layer 230 is implemented by an anisotropic conductive film is exemplified.

After the anisotropic conductive film is positioned on the substrate 210 in a state where the first electrode 220 is positioned, when the semiconductor light emitting device 250 is connected by applying heat and pressure, the semiconductor light emitting device 250 becomes the first It is electrically connected to the electrode 220 . In this case, the semiconductor light emitting device 250 is preferably disposed on the first electrode 220 .

The electrical connection is created because, as described above, when heat and pressure are applied to the anisotropic conductive film, it partially has conductivity in the thickness direction. Accordingly, the anisotropic conductive film is divided into a conductive portion and a non-conductive portion in the thickness direction.

In addition, since the anisotropic conductive film contains an adhesive component, the conductive adhesive layer 230 implements not only electrical connection but also mechanical bonding between the semiconductor light emitting device 250 and the first electrode 220 .

As described above, the semiconductor light emitting device 250 is positioned on the conductive adhesive layer 230 and constitutes individual pixels in the display device through this. Since the semiconductor light emitting device 250 has excellent luminance, individual unit pixels can be configured even with a small size. The size of such an individual semiconductor light emitting device 250 may be, for example, a side length of 80 μm or less, and may be a rectangular or square device. In the case of a rectangular shape, for example, it may have a size of 20 X 80 μm or less.

The semiconductor light emitting device 250 may have a vertical structure.

A plurality of second electrodes 240 disposed in a direction crossing the longitudinal direction of the first electrode 220 and electrically connected to the vertical semiconductor light emitting device 250 are positioned between the vertical semiconductor light emitting devices.

Referring to FIG. 9 , the vertical semiconductor light emitting device 250 includes a p-type electrode 256 , a p-type semiconductor layer 255 formed on the p-type electrode 256 , and a p-type semiconductor layer 255 formed on the p-type semiconductor layer 255 . It includes an active layer 254 , an n-type semiconductor layer 253 formed on the active layer 254 , and an n-type electrode 252 formed on the n-type semiconductor layer 253 . In this case, the lower p-type electrode 256 may be electrically connected to the first electrode 220 and the conductive adhesive layer 230 , and the upper n-type electrode 252 may be a second electrode 240 to be described later. ) can be electrically connected to. The vertical semiconductor light emitting device 250 has a great advantage in that it is possible to reduce the chip size because electrodes can be arranged up and down.

Referring back to FIG. 8 , a phosphor layer 280 may be formed on one surface of the semiconductor light emitting device 250 . For example, the semiconductor light emitting device 250 is a blue semiconductor light emitting device 251 that emits blue (B) light, and a phosphor layer 280 for converting the blue (B) light into the color of a unit pixel is provided. can be In this case, the phosphor layer 280 may be a red phosphor 281 and a green phosphor 282 constituting individual pixels.

That is, a red phosphor 281 capable of converting blue light into red (R) light may be stacked on the blue semiconductor light emitting device at a position constituting the unit pixel of red color, and at a position constituting the unit pixel of green color, blue light A green phosphor 282 capable of converting blue light into green (G) light may be stacked on the semiconductor light emitting device. In addition, only the blue semiconductor light emitting device may be used alone in the portion constituting the blue unit pixel. In this case, unit pixels of red (R), green (G), and blue (B) may form one pixel.

However, the present invention is not necessarily limited thereto, and as described above in a display device to which a flip chip type light emitting device is applied, other structures for implementing blue, red, and green colors may be applied.

Referring back to the present embodiment, the second electrode 240 is positioned between the semiconductor light emitting devices 250 and is electrically connected to the semiconductor light emitting devices 250 . For example, the semiconductor light emitting devices 250 may be arranged in a plurality of columns, and the second electrode 240 may be positioned between the columns of the semiconductor light emitting devices 250 .

Since the distance between the semiconductor light emitting devices 250 constituting individual pixels is sufficiently large, the second electrode 240 may be positioned between the semiconductor light emitting devices 250 .

The second electrode 240 may be formed as a bar-shaped electrode long in one direction, and may be disposed in a direction perpendicular to the first electrode.

Also, the second electrode 240 and the semiconductor light emitting device 250 may be electrically connected to each other by a connection electrode protruding from the second electrode 240 . More specifically, the connection electrode may be an n-type electrode of the semiconductor light emitting device 250 . For example, the n-type electrode is formed as an ohmic electrode for ohmic contact, and the second electrode covers at least a portion of the ohmic electrode by printing or deposition. Through this, the second electrode 240 and the n-type electrode of the semiconductor light emitting device 250 may be electrically connected.

Referring back to FIG. 8 , the second electrode 240 may be positioned on the conductive adhesive layer 230 . In some cases, a transparent insulating layer (not shown) including silicon oxide (SiOx) may be formed on the substrate 210 on which the semiconductor light emitting device 250 is formed. When the second electrode 240 is positioned after the transparent insulating layer is formed, the second electrode 240 is positioned on the transparent insulating layer. In addition, the second electrode 240 may be formed to be spaced apart from the conductive adhesive layer 230 or the transparent insulating layer.

If a transparent electrode such as indium tin oxide (ITO) is used to position the second electrode 240 on the semiconductor light emitting device 250, the ITO material has a problem of poor adhesion to the n-type semiconductor layer. have. Accordingly, the present invention has the advantage of not using a transparent electrode such as ITO by locating the second electrode 240 between the semiconductor light emitting devices 250 . Therefore, it is possible to improve light extraction efficiency by using a conductive material having good adhesion to the n-type semiconductor layer as a horizontal electrode without being limited by the selection of a transparent material.

Referring back to FIG. 8 , a barrier rib 290 may be positioned between the semiconductor light emitting devices 250 . That is, a barrier rib 290 may be disposed between the vertical semiconductor light emitting devices 250 to isolate the semiconductor light emitting devices 250 constituting individual pixels. In this case, the partition wall 290 may serve to separate individual unit pixels from each other, and may be integrally formed with the conductive adhesive layer 230 . For example, by inserting the semiconductor light emitting device 250 into the anisotropic conductive film, the base member of the anisotropic conductive film may form the partition wall.

In addition, when the base member of the anisotropic conductive film is black, the barrier rib 290 may have reflective properties and increase contrast even without a separate black insulator.

As another example, as the barrier rib 190 , a reflective barrier rib may be separately provided. The barrier rib 290 may include a black or white insulator depending on the purpose of the display device.

If the second electrode 240 is directly positioned on the conductive adhesive layer 230 between the semiconductor light emitting device 250 , the barrier rib 290 is formed between the vertical semiconductor light emitting device 250 and the second electrode 240 . can be located between Accordingly, individual unit pixels can be configured with a small size by using the semiconductor light emitting device 250 , and the distance between the semiconductor light emitting devices 250 is relatively large enough to connect the second electrode 240 to the semiconductor light emitting device 250 . ), and there is an effect of realizing a flexible display device having HD picture quality.

Also, as shown in FIG. 8 , a black matrix 291 may be disposed between each phosphor to improve contrast. That is, the black matrix 291 may improve contrast of light and dark.

10 is a perspective view of a display device using a semiconductor light emitting device manufactured by tiling a display module. 11 is an enlarged view of part A of FIG. 10 .

According to an embodiment, a display device using a semiconductor light emitting device may include a frame 310 and a display module 320 arranged in a grid on the frame to output an image signal.

The frame 310 may be configured to support the plurality of display modules 320a to 320d in a flat state. The frame 310 may be made of a metal material or a film material that connects the plurality of display modules 320a to 320d. The frame 310 may include a connector electrically connected to the plurality of display modules 320a to 320d. The frame 310 may provide a power or data signal through the connector.

The display module 320 may be arranged in an N×M grid on the frame. Specifically, FIG. 10 shows an embodiment in which the first display module 320a, the second display module 320b, the third display module 320c, and the fourth display module 320d are arranged in a grid on the frame 310. is showing

The display module 320 may include a base substrate 321 including a wiring circuit and a plurality of semiconductor light emitting devices 322 provided on the base substrate 321 and connected to the wiring circuit. Additionally, the display module 320 may include an encapsulation layer 323 sealing the semiconductor light emitting device 332 . The other display module 320 may further include a film used for a display device. For example, it may be a protective film, a polarizing film, a retardation film, an adhesive film, a colored film, and the like. Here, the film may correspond to the coating layer 324 .

The base substrate 321 may have a configuration including the substrate 110 , the first electrode 120 , the conductive adhesive layer 130 , and the second electrode 140 described with reference to FIG. 3A .

The semiconductor light emitting device 322 may be the flip-chip type semiconductor light emitting device described with reference to FIG. 4 or the vertical semiconductor light emitting device described with reference to FIG. 6 . That is, the semiconductor light emitting device 322 may correspond to tens or several micro-LEDs. Here, the semiconductor light emitting device 322 may have a configuration including a fluorescent layer and a color filter.

The semiconductor light emitting device 322 may include a semiconductor light emitting device 322a emitting red light, a semiconductor light emitting device 322b emitting blue light, and a semiconductor light emitting device 322c emitting green light. The semiconductor light emitting device 322a emitting red light, the semiconductor light emitting device 322b emitting blue light, and the semiconductor light emitting device 322c emitting green light may be arranged as one set to correspond to a pixel of the display device.

A display device using a semiconductor light emitting device according to an embodiment may be manufactured on a large scale by tiling the plurality of display modules 320a to 320d. The plurality of display modules 320a to 320d may form a grid arrangement and may be provided on the frame 310 in close contact with adjacent display modules.

However, when the plurality of display modules 320a to 320d are tiled on the frame 310 and manufactured, the following problem may occur. In this regard, reference is made specifically to FIG. 11 .

First, a step d between the display modules 320a to 320d may occur due to a manufacturing tolerance of each display module 320a to 320d and a coupling tolerance that may occur in the process of coupling to the frame 310 . Here, the step d may mean a height difference between the front surfaces of the display modules 320a to 320d.

The manufacturing tolerance of each of the display modules 320a to 320d may be a cumulative tolerance of manufacturing tolerances occurring in at least one of the base substrate 321 , the encapsulation layer 323 , and the coating film 324 . For example, the manufacturing tolerance between the base substrates 321, the manufacturing tolerance of the encapsulation layer 321, and the manufacturing tolerance between the coating films 324 are accumulated to increase the step d between the respective display modules 320a to 320d. can

Conventional display devices are manufactured with a thickness that can ignore manufacturing tolerances. However, in recent display devices, flexibility is important, and the thickness is gradually decreasing, and this trend acts as a factor that makes the manufacturing tolerance between display modules stand out.

Second, each of the display modules 320a to 320d is arranged on the frame in close contact with each other, but a gap physically inevitably occurs. The gap may act as a factor causing optical loss. The semiconductor light emitting device 322 disposed adjacent to the gap may have poor color realization depending on the angle. Specifically, the semiconductor light emitting device disposed adjacent to the gap may not emit light at a specific angle due to the principle of total optical reflection. The reason is that the gap (gap) is because a layer of air with a low refractive index is formed.

When the optical loss is described with reference to FIG. 11 , the semiconductor light emitting device adjacent to the gap in the first display module 320a shows red light (R) and blue light (R) when viewed obliquely from the direction of the second display module 320b. B) and the combination of green light (G) may be difficult to realize white light. At least one of the red light R, the blue light B, and the green light G may be totally reflected without passing through the gap.

For example, the red light R1 irradiated from the outermost portion of the first display module 320a may not pass through the gap and may be totally reflected on the side surface of the first display module 320a. In this case, the red light R1 irradiated from the outermost portion of the first display module 320a may not reach the user 400 when viewed obliquely from the direction of the second display module 320b.

Likewise, the green light G2 irradiated from the outermost portion of the second display module 320b may not pass through the gap and may be totally reflected on the side surface of the second display module 320b. In this case, the green light B2 irradiated from the outermost part of the second display module 320b may not reach the user 400 when viewed obliquely from the direction of the first display module 320a.

A method for solving the above problem will be reviewed below.

12 is a conceptual diagram for explaining a coating layer that offsets a step difference occurring between display modules. Hereinafter, the same configuration will be described with reference to FIGS. 10 and 11 .

According to an embodiment, a display device using a semiconductor light emitting device includes a frame 310 and a display module 320 arranged in a grid on the frame to output an image signal and a front surface of the plurality of display modules 320a and 320b. It may include a coating layer 324 coated to connect.

Unlike FIG. 11 , the coating layer 324 is not provided separately for each display module 320a and 320b, but may be coated integrally. The coating layer 324 may offset the step d formed between the display modules 320a and 320b, and implement the exposed outer surface in a flat state.

The coating layer 324 may include at least one of an epoxy resin adhesive, a silicone resin adhesive, and an adhesive tape.

The coating layer 324 may be cured to form a planar state after coating the entire surface of the plurality of display modules 320a and 320b in a liquid state. However, when the coating layer 324 is coated to pass through the gap in a liquid state, the coating layer 324 passes through the gap and flows out in the rear direction of the display modules 320a and 320b. can occur

Hereinafter, a method of preventing the liquid coating layer 324 from leaking through the gap will be described.

13 is an enlarged view of part B of FIG. 12 . Hereinafter, a description of the same configuration will be referred to FIG. 12 .

According to an embodiment, a display device using a semiconductor light emitting device includes a frame 310 and a display module 320 arranged in a grid on the frame to output an image signal and a front surface of the plurality of display modules 320a and 320b. It may include a coating layer 324 coated to connect.

The coating layer 324 may include a protrusion 3241 introduced into a gap formed between the plurality of display modules 320a and 320b.

The protrusion 3241 is formed by the self-weight F2 and the adhesive force F3 of the display modules 320a and 320b in a state in which the liquid coating layer 324 and the front surfaces of the plurality of display modules 320a and 320b are coated. can

In order to prevent the liquid coating layer 324 from leaking into the gap formed between the plurality of display modules 320a and 320b before curing, the cohesive force ( F3) This large material can be used. That is, the coating layer 324 may not flow out into the gap due to the cohesive force F3 in the liquid state. (See Fig. 13(a))

In some cases, the display device using the semiconductor light emitting device may further include a sealing member 330 for sealing the gap formed between the plurality of display modules 320a and 320b in the rear direction.

The sealing member 330 may be configured to close the gap while the liquid coating layer 324 is coated. The liquid coating layer 324 may be prevented from being physically leaked into the gap by the sealing member 330 before being cured, or from flowing out due to the pressure F4 of the internal space of the gap. .

The sealing member 330 may be provided along a grid pattern formed by the plurality of display modules 320a and 320b on the frame 310 . Specifically, the sealing member 330 may be provided along a boundary where the plurality of display modules 320a and 320b are to be positioned.

Hereinafter, the function of the protrusion 3241 for preventing optical loss will be described.

14 is a conceptual diagram for explaining a coating layer 324 that prevents optical loss occurring in a gap formed between display modules. Hereinafter, the same configuration will be described with reference to FIGS. 11 to 13 .

According to an embodiment, a display device using a semiconductor light emitting device includes a frame 310 and a display module 320 arranged in a grid on the frame to output an image signal and a front surface of the plurality of display modules 320a and 320b. It may include a coating layer 324 coated to connect.

The coating layer 324 may include a protrusion 3241 introduced into a gap formed between the plurality of display modules 320a and 320b.

The protrusion 3241 may prevent the semiconductor light emitting device 322 adjacent to the gap in the first display module 320a from being totally reflected from the side of the first display module 320a forming the gap. . In the first display module 320a, the light irradiated from the semiconductor light emitting device 322 adjacent to the gap passes through the side surface and the protrusion 3241 of the first display module 320a forming the gap to the second It may be irradiated obliquely in the direction of the display module 320b.

For example, the red light R1 irradiated from the outermost portion of the first display module 320a may maintain a path without being totally reflected by the protrusion 3241 positioned in the gap. In this case, the red light R1 irradiated from the outermost portion of the first display module 320a may reach the user 400 when viewed obliquely from the direction of the second display module 320b.

Similarly, the green light G2 irradiated from the outermost portion of the second display module 320b may maintain a path without being totally reflected by the protrusion 3241 positioned in the gap. In this case, the green light B2 irradiated from the outermost portion of the second display module 320b may reach the user 400 when viewed obliquely from the direction of the first display module 320a.

The protrusion 3241 may include a curved surface convex in a gap direction formed between the plurality of display modules 320a and 320b. The curved portion may perform a function of correcting a path of light passing through a gap without being totally reflected in the lower portion of the protrusion 3241 and transmitting the corrected path to the user 400 .

In some cases, the protrusion 3241 may include a curved portion concave in a gap direction formed between the plurality of display modules 320a and 320b. The curved portion increases the area in contact between the protrusion 3241 and the side surfaces of the display modules 320a and 320b forming the gap, so that the semiconductor light emitting device 322 adjacent to the gap forms a gap. It is possible to prevent total reflection from the side of the display modules 320a and 320b.

15 is a conceptual diagram illustrating a method of manufacturing a display device using a semiconductor light emitting device according to an exemplary embodiment. Hereinafter, the same configuration will be described with reference to FIGS. 10 to 14 .

A method of manufacturing a display device using a semiconductor light emitting device may include preparing the frame 310 ( FIG. 15A ). The frame 310 may be configured to support the plurality of display modules 320 in a flat state. The frame 310 may be made of a metal material or a film material that connects the plurality of display modules 320 to each other.

The semiconductor light emitting device may include the step of providing the sealing member 330 on the frame 310 along the edge of the region where the plurality of display modules 320 are to be located ( FIG. 15( b ) ). The sealing member 330 may perform a function of sealing a gap formed between the plurality of display modules 320 . Specifically, the sealing member 330 may seal the gap formed between the plurality of display modules 320 in the rear direction. In some cases, this step may be omitted.

A method of manufacturing a display device using a semiconductor light emitting device may include arranging a plurality of display modules 320 on a frame 310 (15(c)). The display module 320 arranged on the frame 310 may have a height difference d due to manufacturing tolerance or assembly tolerance. Also, due to physical limitations, a gap may be formed between the plurality of display modules 320 .

In the method of manufacturing a display device using a semiconductor light emitting device, a liquid coating layer 324 is coated so that the front surfaces of the plurality of display modules 320 are connected, and the outer surface to which the coating layer 324 is exposed is cured in a flat state. step (FIG. 15(d)). When the coating layer 324 is positioned on the gap between the plurality of display modules 320 in a liquid state, a protrusion 3241 protruding in the gap direction by its own weight and adhesive force is formed, and the protrusion ( 3241) may be cured in the formed state.

The above description is merely illustrative of the technical spirit of the present invention, and various modifications and variations will be possible without departing from the essential characteristics of the present invention by those skilled in the art to which the present invention pertains.

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 scope equivalent thereto should be construed as being included in the scope of the present invention.

310: frame
320: display module
321: base substrate
322: semiconductor light emitting device
323: encapsulation layer
324: film coating layer
330: sealing member
400: user

Claims (13)

A display device using a semiconductor light emitting device, comprising:
frame;
a plurality of display modules arranged in a grid on the frame to output image signals; and
A display device using a semiconductor light emitting device comprising a; a coating layer coated to connect the front surfaces of the plurality of display modules. According to claim 1,
The coating layer is
A display device using a semiconductor light emitting device, characterized in that the front surfaces of the plurality of display modules are coated with liquid and then cured to offset the step difference between the front surfaces of the plurality of display modules. 3. The method of claim 2,
The coating layer is
A display device using a semiconductor light emitting device, characterized in that the cohesive force of the material in the liquid phase is greater than the adhesive force with the side surface of the display module and the weight of the element. 3. The method of claim 2,
A display device using the semiconductor light emitting device is
The display device using a semiconductor light emitting device, characterized in that it further comprises a sealing member for sealing the gap (gap) formed between the plurality of display modules in a rear direction. 5. The method of claim 4,
The sealing member is
A display device using a semiconductor light emitting device, characterized in that it is provided along a grid pattern formed by a plurality of the display modules on the frame. According to claim 1,
The coating layer is
A display device using a semiconductor light emitting device, characterized in that it includes a protrusion introduced into a gap formed between the plurality of display modules. 7. The method of claim 6,
the protrusion
A display device using a semiconductor light emitting device, characterized in that it includes a curved portion convex in a gap direction formed between the plurality of display modules. According to claim 1,
The coating layer is
A display device using a semiconductor light emitting device, comprising at least one of an epoxy resin adhesive, a silicone resin adhesive, and a tape having adhesive force. According to claim 1,
The display module is
a base substrate including a wiring circuit; and
and a plurality of semiconductor light emitting devices provided on the base substrate and connected to the wiring circuit. A method for manufacturing a display device using a semiconductor light emitting device, comprising:
arranging a plurality of display modules on a frame;
coating a liquid coating layer so that the front surfaces of the plurality of display modules are connected; and
A method of manufacturing a display device using a semiconductor light emitting device comprising a; curing the coating layer in a planar state in which the step difference between the front surfaces of the plurality of display modules is offset. 11. The method of claim 10,
The coating layer is
A method of manufacturing a display device using a semiconductor light emitting device, characterized in that the cohesive force of the material in the liquid phase is greater than the adhesion to the side surface of the display module and the weight of the material. 11. The method of claim 10,
A method of manufacturing a display device using a semiconductor light emitting device,
The method for manufacturing a display device using a semiconductor light emitting device, characterized in that it further comprises the step of applying a sealing member on the frame along the edge of the region where the display module is to be located. 13. The method of claim 12,
The sealing member is
A method of manufacturing a display device using a semiconductor light emitting device, characterized in that in a state in which the plurality of display modules are arranged in the frame, a gap formed between the plurality of display modules is sealed in a rear direction.

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