WO2016186376A1

WO2016186376A1 - Display apparatus using semiconductor light-emitting device and manufacturing method thereof

Info

Publication number: WO2016186376A1
Application number: PCT/KR2016/005015
Authority: WO
Inventors: 최환준; 이병준
Original assignee: 엘지전자 주식회사
Priority date: 2015-05-19
Filing date: 2016-05-12
Publication date: 2016-11-24
Also published as: KR20160136148A

Abstract

The present invention relates to a display apparatus and, more particularly, to a display apparatus using a semiconductor light-emitting device. A display apparatus according to the present invention comprises: a wiring board in which an electrode is disposed; an adhesive layer disposed on the wiring board; a plurality of semiconductor light-emitting devices combined with the adhesive layer and electrically connected to the electrode; and reflective particles, charged in a space formed among the plurality of light-emitting devices, for reflecting light emitted from the semiconductor light-emitting devices.

Description

Display device using semiconductor light emitting device and manufacturing method thereof

The present invention relates to a display device and a method of manufacturing the same, and more particularly, to a flexible display device using a semiconductor light emitting device.

Recently, display apparatuses having excellent characteristics such as thin and flexible have been developed in the display technology field. In contrast, the major displays currently commercialized are represented by LCD (Liguid Crystal Display) and AMOLED (Active Matrix Organic Light Emitting Diodes).

However, there is a problem that the LCD is not fast response time, difficult implementation of the flexible, there is a weak life in the case of AMOLED, short-lived, not good yield yield, the weakness of the flexible.

On the other hand, Light Emitting Diode (LED) is a well-known semiconductor light emitting device that converts current into light.In 1962, red LEDs using GaAsP compound semiconductors were commercialized. It has been used as a light source for display images of electronic devices including communication devices. Therefore, a method of solving the above problems by implementing a flexible display using the semiconductor light emitting device can be presented.

In the flexible display using the semiconductor light emitting device, there may be a need to improve the luminous efficiency of the semiconductor light emitting device. In order to solve this necessity, a method of renewing the structure of the semiconductor light emitting device and the like may be used, but this has the disadvantage of complicating the manufacturing of the semiconductor light emitting device. Thus, the present invention provides a mechanism for improving the luminous efficiency even with a simple structure.

An object of the present invention is to provide a structure for improving the brightness in the display device and a manufacturing method thereof.

Another object of the present invention is to implement a structure that is simply implemented while blocking the leakage of light between the semiconductor light emitting devices.

According to an exemplary embodiment of the present invention, a display apparatus includes a wiring board on which an electrode is disposed, an adhesive layer disposed on the wiring board, a plurality of semiconductor light emitting devices coupled to the adhesive layer and electrically connected to the electrode, and the plurality of semiconductors. Filled in the space formed between the light emitting elements, and includes reflective particles reflecting the light emitted from the semiconductor light emitting elements.

In example embodiments, the adhesive layer may be formed to cover the reflective particles together with the plurality of semiconductor light emitting devices. At least a portion of the adhesive layer is formed to penetrate between the reflective particles.

In an embodiment, the reflecting particles include a nano-sized oxide. The nano-sized oxide may be any one of spherical, acicular and plate-shaped alumina or titania.

In example embodiments, each of the plurality of semiconductor light emitting devices may include a first conductive electrode and a second conductive electrode spaced apart from each other along one direction, and the reflective particles may be disposed along the thickness direction of the display device. The first conductive electrode and the second conductive electrode overlap each other, and are disposed so as not to overlap the other.

The first conductive electrode may have a bottom surface formed at a position farther from the reflective particles from the second conductive electrode. The second conductive electrode may extend to protrude from at least one side of the plurality of semiconductor light emitting devices. The plurality of semiconductor light emitting devices include a first conductive semiconductor layer and a second conductive semiconductor layer on which the first conductive electrode and the second conductive electrode are disposed, respectively, the second conductive electrode and the second conductive electrode. The conductive semiconductor layer may be covered by an insulating part, and the reflective particles may be formed to cover the insulating part.

In addition, the present invention is to grow a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer on a substrate, forming an array of semiconductor light emitting elements on the substrate through etching, the semiconductor light emitting device Forming at least one conductivity type electrode in the semiconductor, charging the reflective particles reflecting light between the semiconductor light emitting elements in the array of semiconductor light emitting elements, and the array of semiconductor light emitting elements charged with the reflective particles. A method of manufacturing a display apparatus, the method comprising: connecting a wiring board to a wiring board and removing the board.

In an embodiment, the charging may include applying the reflective particles to the array of semiconductor light emitting devices, and filling the coated reflective particles between the semiconductor light emitting devices through rolling.

In example embodiments, after forming an array of semiconductor light emitting devices on the substrate, a second conductive electrode is stacked on the second conductive semiconductor layer. After the reflective particles are filled between the semiconductor light emitting devices, a first conductive electrode is stacked on the first conductive semiconductor layer.

In the display device according to the present invention, as the periphery of the individual elements of the semiconductor light emitting devices is surrounded by the reflective particles, the side emitting light of the semiconductor light emitting devices is directed upward. In addition, it is possible to reflect the light toward the lower portion on the track of the light excited by the phosphor. Through this, the brightness of the display device may be improved.

In addition, in the present invention, as the reflective particles are disposed on the side surfaces of the semiconductor light emitting devices, the mixed light is prevented in the display device by blocking the light emitted from the side surfaces.

In addition, in the present invention, by applying the reflective particles, the structure of surrounding the individual elements of the semiconductor light emitting device, despite the simple manufacturing method can be implemented to improve the brightness of the display device.

In addition, in the present invention, as the insulating reflective particles overlap with the conductive electrode, the conductive electrode may be protected from the conductive ball of the conductive adhesive layer.

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

2 is an enlarged view of a portion A of FIG. 1, and FIGS. 3A and 3B are cross-sectional views taken along the lines B-B and C-C of FIG. 2.

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

5A through 5C are conceptual views illustrating various forms of implementing colors in connection with a flip chip type semiconductor light emitting device.

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

7 is a perspective view showing another embodiment of a display device using the semiconductor light emitting device of the invention.

FIG. 8 is a cross-sectional view taken along the line D-D of FIG. 7.

9 is a conceptual diagram illustrating the vertical semiconductor light emitting device of FIG. 8.

FIG. 10 is an enlarged view of portion A of FIG. 1 for explaining another embodiment of the present invention to which a semiconductor light emitting device having a new structure is applied.

FIG. 11A is a cross-sectional view taken along the line E-E of FIG. 10.

FIG. 11B is a cross-sectional view taken along the line F-F of FIG. 11.

12 is a conceptual diagram illustrating the flip chip type semiconductor light emitting device of FIG. 11A.

FIG. 13 is an enlarged view of a portion A of FIG. 1 for explaining still another embodiment of the present invention.

FIG. 14 is a cross-sectional view taken along the line G-G of FIG. 13, and FIG. 15 is a cross-sectional view taken along the line H-H of FIG. 13.

16A, 16B, 16C, 16D, 16E, 16F, 16G, 16H, 17A, 17B, and 17C are cross-sectional views illustrating a method of manufacturing a display device using the semiconductor light emitting device according to the present invention. .

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, and the same or similar components are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used in consideration of ease of specification, and do not have distinct meanings or roles from each other. In addition, in describing the embodiments disclosed herein, when it is determined that the detailed description of the related known technology may obscure the gist of the embodiments disclosed herein, the detailed description thereof will be omitted. In addition, it should be noted that the accompanying drawings are only for easily understanding the embodiments disclosed in the present specification and are not to be construed as limiting the technical spirit disclosed in the present specification by the accompanying drawings.

Also, when an element such as a layer, region or substrate is referred to as being on another component "on", it is to be understood that it may be directly on another element or intermediate elements may be present therebetween. There will be.

The display device described herein includes a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), navigation, and a slate PC. , Tablet PC, Ultra Book, digital TV, desktop computer. However, it will be readily apparent to those skilled in the art that the configuration according to the embodiments described herein may be applied to a device capable of displaying even a new product form developed later.

According to an embodiment, the information processed by the controller of the display apparatus 100 may be displayed using a flexible display.

The flexible display includes a display that can be bent, bent, twisted, foldable, or rollable by external force. For example, a flexible display can be a display fabricated on a thin, flexible substrate that can be bent, bent, folded, or rolled like a paper while maintaining the display characteristics of a conventional flat panel display.

In a state where the flexible display is not bent (for example, a state having an infinite curvature radius, hereinafter referred to as a first state), the display area of the flexible display becomes flat. The display area may be a curved surface in a state in which the first state is bent by an external force (for example, a state having a finite radius of curvature, hereinafter referred to as a second state). As shown in the drawing, the information displayed in the second state may be visual information output on a curved surface. Such visual information is implemented by independently controlling light emission of a sub-pixel disposed in a matrix form. The unit pixel refers to a minimum unit for implementing 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 semiconductor light emitting device that converts current into light. The light emitting diode is formed to have a small size, thereby enabling it to serve as a unit pixel even in the second state.

Hereinafter, a flexible display implemented using the light emitting diode will be described in more detail with reference to the accompanying drawings.

FIG. 2 is a partially enlarged view of portion A of FIG. 1, FIGS. 3A and 3B are cross-sectional views taken along lines BB and CC of FIG. 2, and FIG. 4 is a conceptual diagram illustrating a flip chip type semiconductor light emitting device of FIG. 3A. 5A through 5C are conceptual views illustrating various forms of implementing colors in connection with a flip chip type semiconductor light emitting device.

Referring to FIGS. 2, 3A, and 3B, a display device 100 using a passive matrix (PM) type semiconductor light emitting device is illustrated as a display device 100 using a semiconductor light emitting device. However, the example described below is also applicable to an active matrix (AM) type semiconductor light emitting device.

The display apparatus 100 includes a substrate 110, a first electrode 120, a conductive adhesive layer 130, a second electrode 140, and a plurality of semiconductor light emitting devices 150.

The substrate 110 may be a flexible substrate. For example, in order 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 is an insulating and flexible material. In addition, the substrate 110 may be either a transparent material or an opaque material.

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

In some embodiments, the insulating layer 160 may be disposed on the substrate 110 on which the first electrode 120 is disposed, 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 stacked on the substrate 110 may be one wiring board. More specifically, the insulating layer 160 is made of an insulating and flexible material such as polyimide (PI, Polyimide), PET, and PEN, and can be formed integrally with the substrate 110 to form one substrate.

The auxiliary electrode 170 is an electrode that electrically connects the first electrode 120 and the semiconductor light emitting device 150. The auxiliary electrode 170 is disposed on the insulating layer 160 and 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 passing through the insulating layer 160. The electrode hole 171 may be formed by filling a via material with a conductive material.

Referring to the drawings, 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 is formed between the insulating layer 160 and the conductive adhesive layer 130 or a structure in which the conductive adhesive layer 130 is disposed on the substrate 110 without the insulating layer 160. It is also possible. In the 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. For this purpose, the conductive adhesive layer 130 may be mixed with a conductive material and an adhesive material. In addition, the conductive adhesive layer 130 is flexible, thereby enabling a flexible function in the display device.

In 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 allows electrical interconnection in the Z direction through the thickness, but may be configured as a layer having electrical insulation in the horizontal X-Y direction. Therefore, 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. When the heat and pressure are applied, only the specific portion is conductive by the anisotropic conductive medium. Hereinafter, although the heat and pressure is applied to the anisotropic conductive film, other methods are possible in order for the anisotropic conductive film to be partially conductive. Such a method can be, for example, only one of the heat and pressure applied or UV curing or the like.

In addition, the anisotropic conductive medium may be, for example, conductive balls or conductive particles. According to the drawing, the anisotropic conductive film in this example is a film in which the conductive ball is mixed with the insulating base member, and only a specific portion of the conductive ball is conductive when heat and pressure are applied. The anisotropic conductive film may be in a state in which a core of a conductive material contains a plurality of particles coated by an insulating film made of a polymer material, and in this case, a portion to which heat and pressure are applied becomes conductive by the core as the insulating film is destroyed. . 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 to the anisotropic conductive film as a whole, and the electrical connection in the Z-axis direction is partially formed by the height difference of the counterpart bonded by the anisotropic conductive film.

As another example, the anisotropic conductive film may be in a state containing a plurality of particles coated with a conductive material on the insulating core. In this case, the portion to which the heat and pressure are applied is deformed (pressed) to have conductivity in the thickness direction of the film. As another example, the conductive material may penetrate the insulating base member in the Z-axis direction and have conductivity in the thickness direction of the film. In this case, the conductive material may have a pointed end.

According to the illustration, the anisotropic conductive film may be a fixed array anisotropic conductive film (fixed array ACF) consisting of a conductive ball inserted into one surface of the insulating base member. More specifically, the insulating base member is formed of an adhesive material, and the conductive ball is concentrated on the bottom portion of the insulating base member, and deforms with the conductive ball when heat and pressure are applied to the base member. Therefore, 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 a plurality of layers, in which a conductive ball is disposed in one layer (double- ACF) etc. are all possible.

The anisotropic conductive paste is a combination of a paste and a conductive ball, and may be a paste in which conductive balls are mixed with an insulating and adhesive base material. In addition, solutions containing conductive particles can be solutions in the form of conductive particles or nanoparticles.

Referring to the drawing again, the second electrode 140 is positioned on the insulating layer 160 spaced apart from the auxiliary electrode 170. That is, the conductive adhesive layer 130 is disposed on the insulating layer 160 on 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 may include 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, and an active layer ( The n-type semiconductor layer 153 formed on the 154 and the n-type electrode 152 disposed horizontally spaced apart from the p-type electrode 156 on the n-type semiconductor layer 153. In this case, the p-type electrode 156 may be electrically connected to the auxiliary electrode 170 by the conductive adhesive layer 130, and the n-type electrode 152 may be electrically connected to the second electrode 140.

Referring to FIGS. 2, 3A, and 3B, the auxiliary electrode 170 is formed to be long in one direction, and one auxiliary electrode may be electrically connected to the plurality of semiconductor light emitting devices 150. For example, the p-type electrodes of the left and right semiconductor light emitting devices around 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 thus, between the p-type electrode 156 and the auxiliary electrode 170 of the semiconductor light emitting device 150. Only the portion and the portion between the n-type electrode 152 and the second electrode 140 of the semiconductor light emitting device 150 have conductivity, and the rest of the semiconductor light emitting device does not have a press-fitted conductivity. As such, the conductive adhesive layer 130 not only couples 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 an array of light emitting devices, and a 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, a plurality of first electrodes 120 may be provided, the semiconductor light emitting devices may be arranged in several rows, and the semiconductor light emitting devices 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 may 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 brightness, individual unit pixels may be configured with a small size.

According to an embodiment, the partition wall 190 may be formed between the semiconductor light emitting devices 150. In this case, the partition wall 190 may serve to separate the individual unit pixels from each other, and may be integrally formed with the conductive adhesive layer 130. For example, when the semiconductor light emitting device 150 is inserted 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, even if there is no separate black insulator, the partition 190 may have reflective properties and contrast may be increased.

As another example, a reflective partition may be separately provided as the partition 190. In this case, the partition 190 may include a black or white insulator according to the purpose of the display device. When the partition wall of the white insulator is used, the reflectivity may be improved, and when the partition wall of the black insulator is used, the contrast may be increased at the same time.

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 performs a function of converting the blue (B) light into the color of a unit pixel. The phosphor layer 180 may be a red phosphor 181 or a green phosphor 182 constituting individual pixels.

That is, a red phosphor 181 capable of converting blue light into red (R) light may be stacked on the blue semiconductor light emitting element 151 at a position forming a red unit pixel, and a position forming a green unit pixel. In FIG. 3, a green phosphor 182 capable of converting blue light into green (G) light may be stacked on the blue semiconductor light emitting device 151. In addition, only the blue semiconductor light emitting device 151 may be used alone in a portion of the blue unit pixel. In this case, the unit pixels of red (R), green (G), and blue (B) may form one pixel. More specifically, phosphors of one color may be stacked along each line of the first electrode 120. Therefore, 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, and thus, a unit pixel may be implemented.

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

In addition, a black matrix 191 may be disposed between the respective phosphor layers in order to improve contrast. That is, the black matrix 191 may improve contrast of the contrast.

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

Referring to FIG. 5A, each semiconductor light emitting device 150 is mainly made of gallium nitride (GaN), and indium (In) and / or aluminum (Al) is added together to emit light of various colors including blue. It can be implemented as an element.

In this case, the semiconductor light emitting devices 150 may be red, green, and blue semiconductor light emitting devices, respectively, to form a sub-pixel. For example, the red, green, and blue semiconductor light emitting devices R, G, and B are alternately disposed, and the red, green, and blue unit pixels are arranged by the red, green, and blue semiconductor light emitting devices. These pixels constitute one pixel, and thus, a full color display may be implemented.

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

Referring to FIG. 5C, the red phosphor layer 181, the green phosphor layer 182, and the blue phosphor layer 183 may be provided on the ultraviolet light emitting device UV. As such, the semiconductor light emitting device can be used not only for visible light but also for ultraviolet light (UV) in all areas, and can be extended in the form of a semiconductor light emitting device in which ultraviolet light (UV) can be used as an excitation source of the upper phosphor. .

Referring back to the present example, the semiconductor light emitting device 150 is positioned on the conductive adhesive layer 130 to constitute a unit pixel in the display device. Since the semiconductor light emitting device 150 has excellent brightness, individual unit pixels may be configured with a small size. The size of the individual semiconductor light emitting device 150 may be 80 μm or less in length of one side, and may be a rectangular or square device. In the case of a rectangle, the size may be 20 × 80 μm or less.

In addition, even when a square semiconductor light emitting element 150 having a side length of 10 μm is used as a unit pixel, sufficient brightness for forming a display device appears. Therefore, for example, when the size of the unit pixel is a rectangular pixel in which one side is 600 µm and the other side is 300 µm, the distance of the semiconductor light emitting element is relatively sufficiently large. Therefore, in this case, it is possible to implement a flexible display device having an HD image quality.

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

Referring to this figure, first, the conductive adhesive layer 130 is formed on the insulating layer 160 on which the auxiliary electrode 170 and the second electrode 140 are located. The insulating layer 160 is stacked on the first substrate 110 to form a single substrate (or a wiring substrate), and the first electrode 120, the auxiliary electrode 170, and the second electrode 140 are formed on the wiring substrate. Is placed. In this case, the first electrode 120 and the second electrode 140 may be disposed in a direction perpendicular to each other. In addition, in order to implement a flexible display device, the first substrate 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. For this purpose, an anisotropic conductive film may be applied to a substrate on which the insulating layer 160 is located.

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

In this case, the second substrate 112 may be a growth substrate for growing the semiconductor light emitting device 150, and may be a sapphire substrate or a silicon substrate.

When the semiconductor light emitting device is formed in a wafer unit, the semiconductor light emitting device may be effectively used in the display device by having a gap and a size capable of forming the display device.

Next, the wiring board and the second board 112 are thermocompressed. For example, the wiring board and the second substrate 112 may be thermocompressed by applying an ACF press head. By the thermocompression bonding, the wiring substrate and the second substrate 112 are bonded. Only a portion between the semiconductor light emitting device 150, the auxiliary electrode 170, and the second electrode 140 has conductivity due to the property of the conductive anisotropic conductive film by thermocompression bonding. The device 150 may be electrically connected. At this time, the semiconductor light emitting device 150 is inserted into the anisotropic conductive film, through which a partition wall may be formed between the semiconductor light emitting device 150.

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

Finally, the second 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) 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 phosphor or a green phosphor for converting the blue (B) light into a color of a unit pixel emits the blue semiconductor light. 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. Hereinafter, a vertical structure will be described with reference to FIGS. 5 and 6.

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

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

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

The display device includes a substrate 210, a first electrode 220, a conductive adhesive layer 230, a second electrode 240, and a plurality of semiconductor light emitting devices 250.

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

The first electrode 220 is positioned on the substrate 210 and may be formed as an electrode having a bar shape that is long in one direction. The first electrode 220 may be formed to serve as a data electrode.

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

After the anisotropic conductive film is positioned on the substrate 210 with the first electrode 220 positioned thereon, the semiconductor light emitting device 250 is connected to the semiconductor light emitting device 250 by applying heat and pressure. It is electrically connected to the electrode 220. In this case, the semiconductor light emitting device 250 may be disposed on the first electrode 220.

The electrical connection is created because, as described above, in the anisotropic conductive film is partially conductive in the thickness direction when heat and pressure are applied. Therefore, in the anisotropic conductive film is divided into a portion 231 having conductivity and a portion 232 having no conductivity 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 coupling between the semiconductor light emitting device 250 and the first electrode 220.

As such, the semiconductor light emitting device 250 is positioned on the conductive adhesive layer 230, thereby forming individual pixels in the display device. Since the semiconductor light emitting device 250 has excellent brightness, individual unit pixels may be configured with a small size. The size of the individual semiconductor light emitting device 250 may be 80 μm or less in length of one side, and may be a rectangular or square device. In the case of a rectangle, the size may be 20 × 80 μm or less.

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

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

9, the vertical semiconductor light emitting device includes a p-type electrode 256, a p-type semiconductor layer 255 formed on the p-type electrode 256, and an active layer 254 formed on the p-type semiconductor layer 255. ), 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 by the first electrode 220 and the conductive adhesive layer 230, and the upper n-type electrode 252 may be the second electrode 240 described later. ) Can be electrically connected. Since the vertical semiconductor light emitting device 250 can arrange electrodes up and down, the vertical semiconductor light emitting device 250 has a great advantage of reducing chip size.

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 the phosphor layer 280 is provided to convert the blue (B) light into the color of a unit pixel. 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, at the position forming the red unit pixel, a red phosphor 281 capable of converting the blue light into the red (R) light may be stacked on the blue semiconductor light emitting element 251, and the position forming the green unit pixel. In FIG. 3, a green phosphor 282 capable of converting blue light into green (G) light may be stacked on the blue semiconductor light emitting device 251. In addition, only the blue semiconductor light emitting device 251 may be used alone in a portion of the blue unit pixel. In this case, the 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 the display device to which the flip chip type light emitting device is applied, other structures for implementing blue, red, and green 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 forming the 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 an electrode having a bar shape that is long in one direction, and may be disposed in a direction perpendicular to the first electrode.

In addition, the second electrode 240 and the semiconductor light emitting device 250 may be electrically connected 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 of 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 to each other.

According to the illustration, 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 may not have good adhesion with the n-type semiconductor layer. have. Therefore, the present invention has the advantage of not having to use a transparent electrode such as ITO by placing the second electrode 240 between the semiconductor light emitting devices 250. Therefore, the light extraction efficiency can be improved by using a conductive material having good adhesion with the n-type semiconductor layer as a horizontal electrode without being limited to the selection of a transparent material.

According to an embodiment, the partition wall 290 may be located between the semiconductor light emitting devices 250. That is, the partition wall 290 may be disposed between the vertical semiconductor light emitting devices 250 to isolate the semiconductor light emitting devices 250 forming 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, when the semiconductor light emitting device 250 is inserted 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, even if there is no separate black insulator, the partition wall 290 may have reflective properties and contrast may be increased.

As another example, as the partition 190, a reflective partition may be separately provided. The partition 290 may include a black or white insulator according to the purpose of the display device.

If the second electrode 240 is positioned directly on the conductive adhesive layer 230 between the semiconductor light emitting devices 250, the partition wall 290 is disposed between the vertical semiconductor light emitting device 250 and the second electrode 240. It can be located in between. Accordingly, the individual unit pixels may be configured even 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 so that the second electrode 240 is connected to the semiconductor light emitting device 250. ), And a flexible display device having HD image quality can be implemented.

In addition, according to the drawings, a black matrix 291 may be disposed between the respective phosphors in order to improve contrast. That is, this black matrix 291 can improve contrast of the contrast.

As described above, the semiconductor light emitting device 250 is positioned on the conductive adhesive layer 230, thereby forming individual pixels in the display device. Since the semiconductor light emitting device 250 has excellent brightness, individual unit pixels may be configured with a small size. Therefore, a full color display in which the unit pixels of red (R), green (G), and blue (B) form one pixel may be implemented by the semiconductor light emitting device.

In the display device using the semiconductor light emitting device of the present invention described above, when the flip chip type is applied, since the first and second electrodes are disposed on the same plane, it is difficult to realize a high definition (fine pitch). Hereinafter, a display device to which a flip chip type light emitting device is applied according to another exemplary embodiment of the present invention may be solved.

10 is an enlarged view of a portion A of FIG. 1 for explaining another embodiment of the present invention to which a semiconductor light emitting device having a new structure is applied, FIG. 11A is a cross-sectional view taken along the line EE of FIG. 10, and FIG. 11 is a cross-sectional view taken along the line FF of FIG. 11, and FIG. 12 is a conceptual diagram illustrating the flip chip type semiconductor light emitting device of FIG. 11A.

Referring to FIGS. 10, 11A, and 11B, a display device 1000 using a passive matrix (PM) type semiconductor light emitting device is illustrated as a display device 1000 using a semiconductor light emitting device. However, the example described below is also applicable to an active matrix (AM) type semiconductor light emitting device.

The display apparatus 1000 includes a substrate 1010, a first electrode 1020, a conductive adhesive layer 1030, a second electrode 1040, and a plurality of semiconductor light emitting devices 1050. Here, the first electrode 1020 and the second electrode 1040 may each include a plurality of electrode lines.

The substrate 1010 is a wiring board on which the first electrode 1020 is disposed, and may include polyimide (PI) to implement a flexible display device. In addition, any material that is insulating and flexible may be used.

The first electrode 1020 is positioned on the substrate 1010 and may be formed as an electrode having a bar shape that is long in one direction. The first electrode 1020 may be configured to serve as a data electrode.

The conductive adhesive layer 1030 is formed on the substrate 1010 on which the first electrode 1020 is located. Like the display device to which the above-described flip chip type light emitting device is applied, the conductive adhesive layer 1030 is a solution containing an anisotropic conductive film (ACF), anisotropic conductive paste, and conductive particles. solution, etc. However, in the present embodiment, the conductive adhesive layer 1030 may be replaced with an adhesive layer. For example, if the first electrode 1020 is not located on the substrate 1010 and is integrally formed with the conductive electrode of the semiconductor light emitting device, the adhesive layer may not need conductivity.

A plurality of second electrodes 1040 are disposed between the semiconductor light emitting devices in a direction crossing the length direction of the first electrode 1020 and electrically connected to the semiconductor light emitting devices 1050.

According to the illustration, the second electrode 1040 may be located on the conductive adhesive layer 1030. That is, the conductive adhesive layer 1030 is disposed between the wiring board and the second electrode 1040. The second electrode 1040 may be electrically connected to the semiconductor light emitting device 1050 by contact.

By the above-described structure, the plurality of semiconductor light emitting devices 1050 are coupled to the conductive adhesive layer 1030 and electrically connected to the first electrode 1020 and the second electrode 1040.

In some cases, a transparent insulating layer (not shown) including silicon oxide (SiOx) may be formed on the substrate 1010 on which the semiconductor light emitting device 1050 is formed. When the second electrode 1040 is positioned after the transparent insulating layer is formed, the second electrode 1040 is positioned on the transparent insulating layer. In addition, the second electrode 1040 may be formed to be spaced apart from the conductive adhesive layer 1030 or the transparent insulating layer.

As illustrated, the plurality of semiconductor light emitting devices 1050 may form a plurality of columns in a direction parallel to the plurality of electrode lines provided in the first electrode 1020. However, the present invention is not necessarily limited thereto. For example, the plurality of semiconductor light emitting devices 1050 may form a plurality of columns along the second electrode 1040.

In addition, the display apparatus 1000 may further include a phosphor layer 1080 formed on one surface of the plurality of semiconductor light emitting devices 1050. For example, the semiconductor light emitting device 1050 is a blue semiconductor light emitting device that emits blue (B) light, and the phosphor layer 1080 performs a function of converting the blue (B) light into the color of a unit pixel. The phosphor layer 1080 may be a red phosphor 1081 or a green phosphor 1082 constituting individual pixels. That is, at the position forming the red unit pixel, a red phosphor 1081 capable of converting the blue light into the red (R) light may be stacked on the blue semiconductor light emitting device 1051a, and the position forming the green unit pixel. In the above, a green phosphor 1082 capable of converting blue light into green (G) light may be stacked on the blue semiconductor light emitting device 1051b. In addition, only the blue semiconductor light emitting device 1051c may be used alone in a portion of the blue unit pixel. In this case, the unit pixels of red (R), green (G), and blue (B) may form one pixel. More specifically, phosphors of one color may be stacked along each line of the first electrode 1020. Accordingly, one line in the first electrode 1020 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 1040, and thus a unit pixel may be implemented. However, the present invention is not necessarily limited thereto, and instead of the phosphor, a unit pixel that emits red (R), green (G), and blue (B) by combining a quantum dot (QD) with a semiconductor light emitting element 1050 may be used. Can be implemented.

Meanwhile, in order to improve contrast of the phosphor layer 1080, the display apparatus may further include a black matrix 1091 disposed between the respective phosphors. The black matrix 1091 may form a gap between phosphor dots, and a black material may be formed to fill the gap. As a result, the black matrix 1091 may absorb the external light reflection and improve contrast of the contrast. The black matrix 1091 is positioned between the phosphor layers along the first electrode 1020 in the direction in which the phosphor layers 1080 are stacked. In this case, the phosphor layer is not formed at a position corresponding to the blue semiconductor light emitting element 1051, but the black matrix 1091 has a space without the phosphor layer therebetween (or between the blue semiconductor light emitting element 1051c). On each side) can be formed.

Again, referring to the semiconductor light emitting device 1050 of the present example, since the semiconductor light emitting device 1050 may be disposed up and down in this example, the semiconductor light emitting device 1050 has a great advantage of reducing the chip size. However, although the electrodes are disposed up and down, the semiconductor light emitting device of the present invention may be a flip chip type light emitting device.

12, for example, the semiconductor light emitting device 1050 may include a first conductive semiconductor layer 1155 on which a first conductive electrode 1156, a first conductive electrode 1156 are formed, and An active layer 1154 formed on the first conductive semiconductor layer 1155, and a second formed on the second conductive semiconductor layer 1153 and the second conductive semiconductor layer 1153 formed on the active layer 1154. A conductive electrode 1152.

More specifically, the first conductive electrode 1156 and the first conductive semiconductor layer 1155 may be a p-type electrode and a p-type semiconductor layer, respectively, and the second conductive electrode 1152 and the second conductive layer may be formed. The conductive semiconductor layer 1153 may be an n-type electrode and an n-type semiconductor layer, respectively. However, the present invention is not necessarily limited thereto, and an example in which the first conductive type is n-type and the second conductive type is p-type is also possible.

More specifically, the first conductive electrode 1156 is formed on one surface of the first conductive semiconductor layer 1155, and the active layer 1154 is formed on the other surface of the first conductive semiconductor layer 1155. The second conductive semiconductor layer 1153 is formed between one surface of the second conductive semiconductor layer 1153, and the second conductive electrode 1152 is formed on one surface of the second conductive semiconductor layer 1153.

In this case, the second conductive electrode is disposed on one surface of the second conductive semiconductor layer 1153, and an undoped semiconductor layer 1153a is disposed on the other surface of the second conductive semiconductor layer 1153. ) May be formed.

Referring to FIG. 12 together with FIGS. 10 to 11B, one surface of the second conductive semiconductor layer may be the surface closest to the wiring board, and the other surface of the second conductive semiconductor layer may be closest to the wiring substrate. It can be far away.

In addition, the first conductive electrode 1156 and the second conductive electrode 1152 have a height difference from each other in the width direction and the vertical direction (or thickness direction) at positions spaced apart along the width direction of the semiconductor light emitting device. It is made to have.

The second conductive electrode 1152 is formed on the second conductive semiconductor layer 1153 using the height difference, but is disposed adjacent to the second electrode 1040 positioned above the semiconductor light emitting device. . For example, the second conductive electrode 1152 may have at least a portion of the second conductive electrode 1152 in the width direction from the side surface of the second conductive semiconductor layer 1153 (or the side surface of the undoped semiconductor layer 1153a). It protrudes along. As such, since the second conductive electrode 1152 protrudes from the side surface, the second conductive electrode 1152 may be exposed to the upper side of the semiconductor light emitting device. Through this, the second conductive electrode 1152 is disposed at a position overlapping with the second electrode 1040 disposed above the conductive adhesive layer 1030.

More specifically, the semiconductor light emitting device includes a protrusion 1152a extending from the second conductive electrode 1152 and protruding from the side surfaces of the plurality of semiconductor light emitting devices. In this case, based on the protrusion 1152a, the first conductive electrode 1156 and the second conductive electrode 1152 are disposed at positions spaced apart along the protrusion direction of the protrusion 1152a. It may be represented to have a height difference from each other in the direction perpendicular to the protruding direction.

The protrusion 1152a extends from one surface of the second conductive semiconductor layer 1153 to the side surface, and more specifically to an upper surface of the second conductive semiconductor layer 1153, an undoped semiconductor layer. Extends to 1153a. The protrusion 1152a protrudes along the width direction from the side of the undoped semiconductor layer 1153a. Accordingly, the protrusion 1152a may be electrically connected to the second electrode 1040 on the opposite side of the first conductive electrode based on the second conductive semiconductor layer.

The structure having the protrusion 1152a may be a structure that can utilize the advantages of the above-described horizontal semiconductor light emitting device and vertical semiconductor light emitting device. Meanwhile, fine grooves may be formed on the upper surface furthest from the first conductive electrode 1156 in the undoped semiconductor layer 1153a by roughing.

In addition, the semiconductor light emitting device 1050 may include an insulating portion 1158 formed to cover the second conductive electrode 1152. The insulating part 1158 may be formed to cover a portion of the first conductive semiconductor layer 1155 together with the second conductive electrode 1152.

In this case, the second conductive electrode 1152 and the active layer 1154 are formed on one surface of the second conductive semiconductor layer 1153, and are spaced apart in one direction with the insulating portion 1158 interposed therebetween. do. Here, one direction (or horizontal direction) may be the width direction of the semiconductor light emitting device, the vertical direction may be the thickness direction of the semiconductor light emitting device.

In addition, the first conductive electrode 1156 may be formed in a portion of the first conductive semiconductor layer 1155 that is not covered by the insulating portion 1158 and is exposed. Therefore, the first conductive electrode 1156 is exposed to the outside through the insulating portion 1158.

As such, since the first conductive electrode and the second

conductive electrode

1156 and 1152 are spaced apart by the insulating portion 1058, the n-type electrode and the p-type electrode of the semiconductor light emitting device may be insulated.

In addition, the display apparatus 1000 may further include a phosphor layer 1080 (refer to FIG. 11B) formed on one surface of the plurality of semiconductor light emitting devices 1050. In this case, the light output from the semiconductor light emitting devices is excited using a phosphor, thereby implementing red (R) and green (G). In addition, the aforementioned

black matrices

191, 291, 1091, FIGS. 3B, 8, and 11B serve as partition walls that prevent color mixing between the phosphors.

Furthermore, in the present invention, the structure and manufacturing method of the display device is simple, but the mechanism of increasing the brightness and a method of manufacturing the same are presented.

Hereinafter, the structure of the display device of the present invention for increasing luminance will be described in detail with reference to the accompanying drawings. FIG. 13 is an enlarged view of a portion A of FIG. 1 for explaining another embodiment of the present invention, FIG. 14 is a sectional view taken along the GG of FIG. 13, and FIG. 15 is a sectional view taken along the HH of FIG. .

13, 14, and 15 illustrate a display device 2000 using the flip chip type semiconductor light emitting device described with reference to FIGS. 10 to 12 as a display device using the semiconductor light emitting device. More specifically, the flip chip type semiconductor light emitting device described with reference to FIGS. 10 to 12 exemplifies a case where a mechanism for increasing brightness is added. In this case, the arrow shown in Fig. 14 represents a path of light for increasing the luminance. Meanwhile, the example described below may be applied to a display device using the above-described other type of semiconductor light emitting device.

In the present example described below, the same or similar reference numerals are assigned to the same or similar components as those in the above-described examples with reference to FIGS. 10 to 12, and the description is replaced with the first description. For example, the display apparatus 2000 includes a substrate 2010, a first electrode 2020, a conductive adhesive layer 2030, a second electrode 2040, and a plurality of semiconductor light emitting devices 2050. The description will be replaced with the description with reference to FIGS. 10 to 12. Therefore, in the present exemplary embodiment, the conductive adhesive layer 2030 is replaced with an adhesive layer, and a plurality of semiconductor light emitting devices are attached to the adhesive layer disposed on the substrate 2010, and the first electrode 2020 is formed on the substrate 2010. It may be formed integrally with the conductive electrode of the semiconductor light emitting device without being located at.

The second electrode 2040 may be located on the conductive adhesive layer 2030. That is, the conductive adhesive layer 2030 is disposed between the wiring board and the second electrode 2040. The second electrode 2040 may be electrically connected to the semiconductor light emitting device 2050 by contact.

In addition, the semiconductor light emitting device 2050 may include a first conductive electrode 2156, a first conductive semiconductor layer 2155 on which the first conductive electrode 2156 is formed, and a first conductive semiconductor layer 2155. ) And a second conductive type electrode 2152 formed on the second conductive type semiconductor layer 2153 and the second conductive type semiconductor layer 2153 formed on the active layer 2154. The description thereof will be replaced with the description with reference to FIG. 12.

In addition, as described above with reference to FIG. 12, the protrusion 2152a extends from one surface of the second conductive semiconductor layer 2153 to the side surface, and to the top surface of the second conductive semiconductor layer 2153. Specifically, it extends to the undoped semiconductor layer 2153a. Thus, the protrusion 2152a may be electrically connected to the second electrode 2040 on the opposite side of the first conductive electrode based on the second conductive semiconductor layer.

In addition, the semiconductor light emitting device 2050 may include an insulating portion 2158 formed to cover the second conductive electrode 2152. The insulating part 2158 may be formed to cover a portion of the first conductive semiconductor layer 2155 together with the second conductive electrode 2152.

In addition, the first conductive electrode 2156 may be formed at a portion of the first conductive semiconductor layer 2155 that is not covered by the insulating portion 2158 and is exposed. Therefore, the first conductive electrode 2156 is exposed to the outside through the insulating portion 2158.

In addition, the display apparatus 2000 may further include a phosphor layer 2080 formed on one surface of the plurality of semiconductor light emitting devices 2050. For example, the semiconductor light emitting device 2050 is a blue semiconductor light emitting device that emits blue (B) light, and the phosphor layer 2080 performs a function of converting the blue (B) light into the color of a unit pixel. In this case, the light output from the semiconductor light emitting devices 2050 is excited using a phosphor, thereby implementing red (R) and green (G). Meanwhile, the phosphor layer 2080 may be replaced with a color filter or quantum dot. In addition, the aforementioned

black matrices

Referring to the drawings, reflecting particles 2060 are filled in a space formed between the plurality of semiconductor light emitting devices 2050 to reflect light emitted from the semiconductor light emitting devices 2050. The reflective particles 2060 may include a nano-sized oxide, and the nano-sized oxide may be any one of spherical, acicular, and plate-shaped alumina or titania.

In this case, the conductive adhesive layer 2030 electrically and physically connecting the wiring board 2010 and the semiconductor light emitting devices 2050 may include the reflective particles 2060 together with the plurality of semiconductor light emitting devices 2050. ) Is formed to cover. In addition, at least a portion of the conductive adhesive layer 2030 may penetrate between the reflective particles 2060. As an example, an insulating base member or base material of the conductive adhesive layer 2030 may penetrate between the reflective particles 2060.

On the other hand, the reflective particles 2060 may be disposed in different forms in both directions perpendicular to each other. More specifically, the semiconductor light emitting devices 2050 may form a light emitting device array, and the light emitting device array may be formed to have a narrow interval between the semiconductor light emitting devices in a horizontal direction and to be wide in a vertical direction. In this case, the vertical direction may be defined as a direction in which the second conductive electrode protrudes, and the horizontal direction may be a direction perpendicular to the vertical direction. Meanwhile, the phosphor layer 2080 is formed to extend in the longitudinal direction, and

phosphor layers

2081 and 2082 implementing different colors are sequentially arranged along the horizontal direction.

In this case, the reflective particles 2060 may fill the gap in the horizontal direction where the gap is narrow, and the reflective particles 2060 may fill only a portion of the gap in the longitudinal direction where the gap is relatively wide. have. Since only a part of the gap is filled in the longitudinal direction, the first portion 2061 with the reflective particles disposed between the conductive adhesive layer 2030 and the phosphor layer 2080 in the longitudinal direction, and the undisposed first agent. Two portions 2062 may be formed. This is because the phosphor layer of the same color along the longitudinal direction covers the first portion 2061 and the second portion 2062 together, so that only the luminance increase is required along the longitudinal direction, so that the problem of color mixing does not occur. Because.

The reflective particles 2060 may reflect light reflected from the phosphor layer 2080 and directed toward the inside of the display device to the phosphor layer 2080. In this case, in order to reflect back light reflected from the phosphor layer 2080 to the inside of the display device, the unarranged second portion 2062 may be formed of a layer having reflective particles formed therein than the first portion 2061. It can be a thin layer. That is, for the re-reflection, the second particles 2062 are disposed in a smaller amount than the first portion 2061, not completely unplaced.

As illustrated, the reflective particles 2060 overlap with one of the first conductive electrode 2156 and the second conductive electrode 2152 along the thickness direction of the display device, and do not overlap with the other. May be arranged so as not to. As an example, the reflective particles 2060 may be formed to overlap the second conductive electrode 2152 and not overlap the first conductive electrode 2156.

More specifically, the reflective particles are formed to cover the insulating portion 2158, and since the insulating portion is disposed between the reflective particles and the second conductive electrode 2152, the reflective particles 2060 are formed. It may overlap with the second conductive electrode 2152. On the other hand, since the first conductive electrode 2156 is provided without being covered by the insulating portion 2158, the reflective particles are formed so as not to cover the first conductive electrode 2156. .

This is because the first conductive electrode 2156 is connected to the wiring electrode at the lower side and the second conductive electrode 2152 at the upper side in the thickness direction of the display device. More specifically, the first conductive electrode 2156 has a lower surface formed at a position farther from the second conductive electrode 2152 than the reflective particles 2060, and the lower surface is electrically connected to the wiring electrode. Connected.

According to the structure of the new display device described above, a structure that improves luminance and a structure that is simply implemented while blocking leakage of light between the semiconductor light emitting devices may be implemented.

Hereinafter, a manufacturing method for forming the structure of the new display device described above will be described in more detail with reference to the accompanying drawings. 16A, 16B, 16C, 16D, 16E, 16F, 16G, 16H, 17A, 17B, and 17C are cross-sectional views illustrating a method of manufacturing a display device using the semiconductor light emitting device according to the present invention. .

First, according to the manufacturing method, the second conductive semiconductor layer 2053, the active layer 2054, and the first conductive semiconductor layer 2055 are grown on the growth substrate W or the semiconductor wafer (FIG. 16A).

When the second conductive semiconductor layer 2053 is grown, an active layer 2054 is grown on the first conductive semiconductor layer 2052, and then a first conductive semiconductor is formed on the active layer 2054. Grow layer 2055. As such, when the second conductive semiconductor layer 2053, the active layer 2054, and the first conductive semiconductor layer 2055 are sequentially grown, as shown in the drawing, the second conductive semiconductor layer 2053 and the active layer ( 2054 and the first conductive semiconductor layer 2055 form a stacked structure.

The growth substrate W may be formed of a material having a light transmissive property, for example, sapphire (Al 2 O 3), GaN, ZnO, or AlO, but is not limited thereto. In addition, the growth substrate W may be formed of a material suitable for growing a semiconductor material, a carrier wafer. At least one of Si, GaAs, GaP, InP, and Ga2O3 may be formed of a material having excellent thermal conductivity, including a conductive substrate or an insulating substrate, for example, a SiC substrate having a higher thermal conductivity than a sapphire (Al2O3) substrate. Can be used.

The second conductive semiconductor layer 2053 is an n-type semiconductor layer, and may be a nitride semiconductor layer such as n-Gan, and may further include an undoped semiconductor layer 2153a.

Next, an etching process for separating the p-type semiconductor and the n-type semiconductor is performed. For example, referring to FIG. 16B, at least a portion of the first conductive semiconductor layer 2055 and the active layer 2054 are etched to partition the first conductive semiconductor layer 2055 into a plurality of portions ( Mesa etching). In this case, a portion of the active layer 2054 and the first conductive semiconductor layer 2055 are removed in the vertical direction, and the second conductive semiconductor layer 2053 is exposed to the outside. The etching forms an array of semiconductor light emitting devices on the substrate.

Next, a plurality of semiconductor light emitting devices that are isolated from each other on the substrate are formed through etching (see FIG. 16C). In this case, the etching may proceed until the undoped semiconductor layer is exposed. As another example, etching may be performed until a part of the second conductive semiconductor layer 2053 is left between the semiconductor light emitting devices.

Next, at least one conductive electrode is formed on the semiconductor light emitting devices (FIG. 16D). More specifically, the second conductive electrode 2052 is formed on one surface of the second conductive semiconductor layer 2053. That is, after forming an array of semiconductor light emitting devices on the substrate, a second conductive electrode 2052 is stacked on the second conductive semiconductor layer 2053.

Thereafter, in the state where the second conductive electrode 2052 is formed, the insulator is applied to form the insulator 2058 (FIG. 16E).

The second conductive electrode 2052 and the active layer 2054 are formed on one surface of the second conductive semiconductor layer 2053, and are spaced apart in the horizontal direction with the insulating portion 2058 interposed therebetween. In addition, the plurality of semiconductor light emitting devices forming the light emitting device array may be disposed to be spaced apart from adjacent light emitting devices with a predetermined space therebetween, and may be filled with an insulating portion 2058 between the spaced apart semiconductor light emitting devices. . In addition, the insulating portion 2058 is formed so as not to cover a portion of the first conductive semiconductor layer 2055 for electrical connection of the first conductive electrode 2056.

Next, the filling of reflective particles reflecting light between the semiconductor light emitting devices in the array of semiconductor light emitting devices is performed (FIGS. 16F and 16G).

The charging step includes applying the reflective particles to the array of semiconductor light emitting devices (FIG. 16F), and filling the coated reflective particles between the semiconductor light emitting devices (FIG. 16G) through rolling. can do.

In the applying step, a solvent in which the oxides of the nanoparticles are dispersed is applied by a spray method, and in the filling step, the applied solvent is pressed by using a roller or rubber to nano-measure the mesa space of the semiconductor light emitting devices. To fill the particles. Pressurization of the rollers or rubbers may be repeatedly applied in the horizontal and vertical directions.

As described above, after the reflective particles are filled between the semiconductor light emitting devices, a first conductive electrode is stacked on the first conductive semiconductor layer (FIG. 16H).

According to this process, the reflective particles are filled in the space formed between the plurality of semiconductor light emitting devices, it can be implemented to reflect the light emitted from the semiconductor light emitting devices.

Subsequently, the array of semiconductor light emitting devices filled with the reflective particles is connected to a wiring board and the substrate is removed.

For example, the semiconductor light emitting devices are bonded to the wiring board using the conductive adhesive layer, and the growth substrate is removed (FIG. 17A). The wiring board is in a state where a first electrode 2020 is formed, and the first electrode 2020 is a lower wiring and is electrically connected to the first conductive electrode 2156 by a conductive ball in the conductive adhesive layer 2030. do. At this time, at least a part of the conductive adhesive layer penetrates between the reflective particles by thermal compression.

Thereafter, after the undoped semiconductor layer 2153a is etched and removed (FIG. 17B), a second electrode 2040 connecting the protruding second conductive electrode 2152 is formed (FIG. 17c). The second electrode 2040 is an upper wiring and is directly connected to the second conductive electrode 2152.

However, the present invention is not necessarily limited thereto, and the undoped semiconductor layer may be replaced with another type of absorbing layer that absorbs a UV laser. The absorber layer may be a buffer layer, may be formed in a low temperature atmosphere, and may be formed of a material that can alleviate the difference in lattice constant between the semiconductor layer and the growth substrate. For example, it may include materials such as GaN, InN, AlN, AlInN, InGaN, AlGaN, and InAlGaN.

According to the manufacturing method described above, by applying the reflective particles, depending on the structure surrounding the individual elements of the semiconductor light emitting device, the brightness of the display device can be improved despite the simple manufacturing method.

The display device using the semiconductor light emitting device described above is not limited to the configuration and method of the embodiments described above, but the embodiments may be configured by selectively combining all or part of the embodiments so that various modifications may be made. It may be.

Claims

A wiring board on which electrodes are disposed;

An adhesive layer disposed on the wiring board;

A plurality of semiconductor light emitting devices coupled to the adhesive layer and electrically connected to the electrodes; And

And a reflective particle filled in a space formed between the plurality of semiconductor light emitting devices to reflect light emitted from the semiconductor light emitting devices.
The method of claim 1,

And the adhesive layer is formed to cover the reflective particles together with the plurality of semiconductor light emitting devices.
The method of claim 2,

At least a portion of the adhesive layer penetrates between the reflective particles.
The method of claim 1,

And the reflective particles comprise a nano-sized oxide.
The method of claim 4, wherein

The nano-sized oxide is any one of spherical, acicular and plate-shaped alumina or titania.
The method of claim 1,

Each of the plurality of semiconductor light emitting devices includes a first conductive electrode and a second conductive electrode which are spaced apart from each other along one direction.

And the reflective particles overlap with any one of the first conductive electrode and the second conductive electrode in the thickness direction of the display device, and are arranged not to overlap with the other.
The method of claim 6,

And the first conductive electrode has a lower surface formed at a position farther from the second conductive electrode than the reflective particles.
The method of claim 6,

The second conductive electrode extends to protrude from at least one side of the plurality of semiconductor light emitting devices.
The method of claim 6,

The plurality of semiconductor light emitting devices include a first conductive semiconductor layer and a second conductive semiconductor layer on which the first conductive electrode and the second conductive electrode are disposed, respectively.

And the second conductive electrode and the second conductive semiconductor layer are covered by an insulating part, and the reflective particles cover the insulating part.
Growing a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer on the substrate;

Forming an array of semiconductor light emitting devices on the substrate through etching, and forming at least one conductive electrode on the semiconductor light emitting devices;

Charging reflective particles reflecting light between the semiconductor light emitting devices in the array of semiconductor light emitting devices; And

And connecting the array of semiconductor light emitting devices filled with the reflective particles with a wiring substrate and removing the substrate.
The method of claim 10,

The charging step,

Applying the reflective particles to the array of semiconductor light emitting devices; And

And filling the coated reflective particles between the semiconductor light emitting devices through rolling.
The method of claim 10,

After forming an array of semiconductor light emitting devices on the substrate, a second conductive electrode is stacked on the second conductive semiconductor layer,

And after the reflective particles are filled between the semiconductor light emitting devices, a first conductive electrode is stacked on the first conductive semiconductor layer.