KR20190075869A - Display device using micro led and manufacturing method thereof - Google Patents

Abstract

According to the present invention, disclosed are a display device using a micro LED and a manufacturing method thereof, which can be easily manufactured while being applicable to a large-screen display device and reducing manufacturing costs. Here, according to an embodiment of the present invention, the device comprises at least one LED to be assembled to the substrate. The substrate includes: an assembly electrode layer on which an assembly electrode is disposed; an insulation layer applied to the upper part of the assembly electrode; and an assembling groove including a partition in the upper part of the insulating layer. The LED includes a first electrode, a first semiconductor layer, an active layer, a second semiconductor layer, and a second electrode stacked in a first direction. The assembly surface is formed in a second direction corresponding to the stacked first direction.

Description

TECHNICAL FIELD [0001] The present invention relates to a display device using a micro LED,

The present invention is applicable to a display device related technology field, for example, a display device using a micro LED (Light Emitting Diode) and a method of manufacturing the same.

In recent years, display devices having excellent characteristics such as a thin shape and a flexible shape in the field of display technology have been developed. On the other hand, major displays that are currently commercialized are represented by LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diodes).

However, in the case of an LCD, there is a problem that the reaction time is not fast and the implementation of the flexible is difficult. In the case of the OLED, the lifetime is short and the mass production yield is poor.

Meanwhile, a light emitting diode (LED) is a semiconductor light emitting device well known to convert current into light. In 1962, a red LED using a GaAsP compound semiconductor was commercialized, and a GaP: N LED Has been used as a light source for a display image of an electronic device including an information communication device. Accordingly, a method of implementing the display using the semiconductor light emitting device and solving the above-described problems can be presented. Such a light emitting diode has various advantages such as long lifetime, low power consumption, excellent initial driving characteristic, and high vibration resistance as compared with a filament-based light emitting device.

On the other hand, in the case of a display using a semiconductor light emitting device, the semiconductor light emitting device corresponding to each pixel must be coupled to the substrate, so that it is relatively difficult to implement a large screen display.

In addition, in order to realize a large-area high-resolution display, a large amount of semiconductor light-emitting devices are required, and therefore efforts to reduce the manufacturing cost of individual semiconductor light-emitting devices are required.

An object of an embodiment of the present invention is to provide a display device using a vertical type semiconductor light emitting device and a manufacturing method thereof which can reduce manufacturing cost.

An object of another embodiment of the present invention is to provide a manufacturing method which is applicable to a display device of a large screen and can reduce a defect rate.

Furthermore, another object of the present invention is to solve various problems not mentioned here. Skilled artisans may understand from the full scope of the specification and drawings.

According to another aspect of the present invention, there is provided a method of manufacturing a display device, including: forming an assembled electrode on a substrate; Applying an insulating layer to the substrate on which the assembly electrode is formed; Forming an assembly groove including a barrier rib on the substrate coated with the insulating layer; Providing an LED having an assembly surface corresponding to the assembly groove; And assembling the assembly surface of the LED into the assembly groove, wherein the providing of the LED comprises: providing a first electrode, a first semiconductor layer, an active layer, a second semiconductor layer, and a second electrode, The method of claim 1, further comprising laminating in a first direction, wherein the mounting surface is formed in a second direction corresponding to the stacked first direction.

In an embodiment, the second direction is a horizontal direction in the stacked first direction.

In an embodiment, the step of assembling the assembly surface of the LED into the assembly groove includes: contacting the assembly surface of the LED with the assembly groove using an assembly device having a magnetic body; And assembling the assembly surface of the LED into the assembly groove based on an electric field applied through the assembly electrode formed on the substrate.

In an embodiment, the LED has a lateral length (X) in a first direction in which the LEDs are stacked and a first vertical direction, and a longitudinal length (Y) in a first direction and a second vertical direction in which the LEDs are stacked The transverse length X has at least two values different from each other, and the vertical length Y has a fixed value.

The step of forming the assembly electrodes on the substrate may include forming the assembly electrodes apart from each other so as to overlap the partition walls provided on both sides of the assembly groove, To form an electrode.

In an embodiment, the first semiconductor layer is an N-type GaN layer and the second semiconductor layer is a P-type GaN layer.

In an embodiment, the LED is characterized in that it comprises a magnetic layer.

In an embodiment, the substrate includes at least one of glass, a conductor, and a flexible polymer material.

In an embodiment, the step of forming the mounting groove includes forming a polymer adhesive layer on at least a part of the lower portion of the mounting groove on which the mounting surface of the LED is mounted.

In an embodiment, the step of forming the mounting groove includes forming a metal reflecting film on at least a part of the lower portion of the mounting groove on which the active layer of the LED is mounted.

In an embodiment, the substrate is provided with a TFT for driving an active matrix.

In an embodiment, the LED is a micro-LED having a micrometer size. In an embodiment, the substrate is provided with a transistor for active matrix driving.

According to an embodiment of the present invention, there is provided an apparatus including at least one LED incorporated in a substrate, the substrate including: an assembling electrode layer in which an assembling electrode is disposed; An insulating layer applied over the assembly electrode; And an assembly groove including a barrier rib on the insulating layer, wherein the LED has a first electrode, a first semiconductor layer, an active layer, a second semiconductor layer, and a second electrode stacked in a first direction, Are formed in a second direction corresponding to the stacked first direction.

According to an embodiment of the present invention, a vertical type semiconductor light emitting device is used in a display device using a semiconductor light emitting device, thereby reducing the manufacturing cost of an individual semiconductor light emitting device.

According to another embodiment of the present invention, since the vertical type semiconductor light emitting device has an assembling surface corresponding to an assembly groove of the substrate, a technical effect that a large number of semiconductor light emitting devices can be easily assembled onto a substrate through self- have.

Further, according to another embodiment of the present invention, there are additional technical effects not mentioned here. Skilled artisans may understand from the full scope of the specification and drawings.

1 is a conceptual diagram showing an embodiment of a display device using the semiconductor light emitting device of the present invention.
2 is a partially enlarged view of a portion A in Fig.
Figs. 3A and 3B are cross-sectional views taken along line BB and CC in Fig.
4 is a conceptual diagram showing a flip chip type semiconductor light emitting device of FIG.
FIGS. 5A to 5C are conceptual diagrams showing various forms of implementing a color 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 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 present invention.
8 is a cross-sectional view taken along the line DD of FIG.
9 is a conceptual diagram showing a vertical semiconductor light emitting device of FIG.
10 is a view illustrating a process of manufacturing a substrate having an assembly groove for assembling a semiconductor light emitting device according to another embodiment of the present invention.
FIG. 11 is a view showing a method of arranging the assembled electrodes included in the substrate of FIG. 10 and a metal layer formed additionally.
12 is a view schematically showing the structure of a vertical type semiconductor light emitting device assembled to the substrate of FIG.
13 is a plan view of various shapes that the vertical semiconductor light emitting device of FIG. 12 may have.
14 is a plan view and a cross-sectional view of the substrate having the mounting groove of Fig.
FIG. 15 is a view schematically showing a process of assembling the vertical semiconductor light emitting device of FIG. 12 on a substrate having the mounting groove of FIG.
FIG. 16 is a view showing an adhesive layer for fixing the vertical type semiconductor light emitting device to the substrate having the mounting groove of FIG. 10; FIG.
FIG. 17 is a view showing that a reflective layer is included in an upper part of the substrate having the mounting groove of FIG. 10;
FIG. 18 is a view showing electrode pads formed on the vertical semiconductor light emitting device assembled according to the embodiment of FIGS. 10 and 12. FIG.
Fig. 19 is a cross-sectional view of a display device manufactured according to the embodiment of Figs. 10 and 12. Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. In addition, it should be noted that the attached drawings are only for easy understanding of the embodiments disclosed in the present specification, and should not be construed as limiting the technical idea disclosed in the present specification by the attached drawings.

Further, although the respective drawings are described for convenience of explanation, it is also within the scope of the present invention that a person skilled in the art can combine at least two drawings to implement other embodiments.

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

The display device described in this specification is a concept including all display devices that display information as a unit pixel or a set of unit pixels. Therefore, the present invention can be applied not only to finished products but also to parts. For example, a panel corresponding to one part of a digital TV corresponds to the display device of the present invention on its own. The final product includes mobile phones, smart phones, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation systems, slate PCs, Books, digital TVs, desktop computers, and the like.

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 being displayed, even in the form of a new product to be developed in the future.

In addition, the semiconductor light emitting device mentioned in this specification includes an LED, a micro LED, and the like.

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

As shown in FIG. 1, information processed in a control unit (not shown) of the display device 100 may be displayed using a flexible display.

The flexible display includes, for example, a display that can be bent or curved by external force, or which can be twisted, collapsed, or can be curled.

Further, the flexible display can be a display that is fabricated on a thin and flexible substrate that can be bent, bent, folded or rolled, such as paper, while maintaining the display characteristics of a conventional flat panel display, for example.

In a state where the flexible display is not bent (for example, a state having an infinite radius of curvature, hereinafter referred to as a first state), the display area of the flexible display is flat. In the first state, the display area may be a curved surface in a state of being 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 FIG. 1, the information displayed in the second state may be time information output on the curved surface. Such visual information is realized by independently controlling the emission of a sub-pixel arranged in a matrix form. The unit pixel means, for example, 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 one type of semiconductor light emitting device for converting a current into light. The light emitting diode is formed in 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 now be described in more detail with reference to the drawings.

2 is a partially enlarged view of a portion A in Fig.

Figs. 3A and 3B are cross-sectional views taken along lines B-B and C-C of Fig.

4 is a conceptual diagram showing a flip chip type semiconductor light emitting device of FIG.

FIGS. 5A to 5C are conceptual diagrams showing various forms of implementing a color in relation to a flip-chip type semiconductor light emitting device.

As shown in FIGS. 2, 3A and 3B, a display device 100 using a passive matrix (PM) semiconductor light emitting device as a display device 100 using a semiconductor light emitting device is illustrated. However, the example described below is also applicable to an active matrix (AM) 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- (150).

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

The substrate 110 may be a wiring substrate on which the first electrode 120 is disposed, so that the first electrode 120 may be positioned on the substrate 110.

3A, the insulating layer 160 may be disposed on the substrate 110 on which the first electrode 120 is located, and the auxiliary electrode 170 may be disposed on the insulating layer 160. Referring to FIG. In this case, a state in which the insulating layer 160 is laminated on the substrate 110 may be one wiring substrate. More specifically, the insulating layer 160 is formed of a flexible material such as polyimide (PI), polyimide (PET), or PEN, 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 and is disposed on the insulating layer 160 and corresponds to the position of the first electrode 120. For example, the auxiliary electrode 170 may be in the form of a dot 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 hole with a conductive material.

As shown in FIG. 2 or 3A, the conductive adhesive layer 130 is formed on one surface of the insulating layer 160, but the present invention is not limited thereto. For example, a layer having a specific function may be 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. To this end, the conductive adhesive layer 130 may be mixed with a substance having conductivity and a substance having adhesiveness. Also, the conductive adhesive layer 130 has ductility, thereby enabling the flexible function in the display device.

As an 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 formed as a layer having electrical insulation in the horizontal X-Y direction while permitting electrical interconnection in the Z direction passing through the thickness. Accordingly, the conductive adhesive layer 130 may be referred to as a Z-axis conductive layer (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 heat and pressure are applied, only a specific part of the anisotropic conductive film has conductivity due to the anisotropic conductive medium. Hereinafter, heat and pressure are applied to the anisotropic conductive film. However, another method may be applied to partially conduct the anisotropic conductive film. Other methods described above may be applied, for example, only one of the above heat and pressure, UV curing, or the like.

In addition, the anisotropic conduction medium can be, for example, a conductive ball or a conductive particle. For example, the anisotropic conductive film is a film in which conductive balls are mixed with an insulating base member. When heat and pressure are applied, only specific portions are conductive by the conductive balls. The anisotropic conductive film may be a state in which a plurality of particles coated with an insulating film made of a polymer material are contained in the core of the conductive material. In this case, the insulating film is broken by heat and pressure, . 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 mating member adhered by the anisotropic conductive film.

As another example, the anisotropic conductive film may be in a state in which a plurality of particles coated with a conductive material are contained in the insulating core. In this case, the conductive material is deformed (pressed) to the portion where the heat and the pressure are applied, so that the conductive material becomes conductive in the thickness direction of the film. As another example, it is possible that the conductive material penetrates the insulating base member in the Z-axis direction and has conductivity in the thickness direction of the film. 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 an insulating base member. More specifically, the insulating base member is formed of a material having adhesiveness, and the conductive ball is concentrated on the bottom portion of the insulating base member, and is deformed together with the conductive ball when heat and pressure are applied to the base member So that they have conductivity in the vertical direction.

However, the present invention is not limited thereto. The anisotropic conductive film may be formed by randomly mixing conductive balls into an insulating base member or by forming a plurality of layers in which a conductive ball is placed in a double- ACF) are all available.

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. In addition, a solution containing conductive particles can be a solution in the form of conductive particles or nanoparticles.

Referring again to FIG. 3A, the second electrode 140 is located in the insulating layer 160 away 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 disposed.

After the conductive adhesive layer 130 is formed in a state where the auxiliary electrode 170 and the second electrode 140 are positioned in the insulating layer 160, the semiconductor light emitting device 150 is connected to the semiconductor light emitting device 150 in a flip chip form 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 semiconductor layer 155 in which a p-type electrode 156, a p-type electrode 156 are formed, an active layer 154 formed on the p-type semiconductor layer 155, And an n-type electrode 152 disposed on the n-type semiconductor layer 153 and the p-type electrode 156 on the n-type semiconductor layer 153 and 154 in the horizontal direction. In this case, the p-type electrode 156 can be electrically connected to the auxiliary electrode 170 and the conductive adhesive layer 130 shown in Fig. 3, and the n-type electrode 152 can be electrically connected to the second electrode 140 .

Referring again to FIGS. 2, 3A and 3B, the auxiliary electrode 170 is elongated 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 right and left semiconductor light emitting elements may be electrically connected to one auxiliary electrode around the auxiliary electrode.

More specifically, the semiconductor light emitting device 150 is pressed into the conductive adhesive layer 130 by heat and pressure, and the portion between the p-type electrode 156 of the semiconductor light emitting device 150 and the auxiliary electrode 170 And only the portion between the n-type electrode 152 and the second electrode 140 of the semiconductor light emitting device 150 has conductivity. In the remaining portion, the semiconductor light emitting device does not have a press-fitting function, The conductive adhesive layer 130 not only couples the semiconductor light emitting device 150 and the auxiliary electrode 170 and 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 element array, and the phosphor layer 180 is formed in the light emitting element array.

The light emitting element array may include a plurality of semiconductor light emitting elements having different brightness values. Each of the semiconductor light emitting devices 150 constitutes a unit pixel and is electrically connected to the first electrode 120. For example, the first electrodes 120 may be a plurality of semiconductor light emitting devices, and the semiconductor light emitting devices may be electrically connected to any one of the plurality of first electrodes.

Also, since the semiconductor light emitting devices are connected in a flip chip form, the semiconductor light emitting devices grown on the transparent dielectric substrate can be used. The semiconductor light emitting devices may be, for example, a nitride semiconductor light emitting device. Since the semiconductor light emitting device 150 has excellent brightness, individual unit pixels can be formed with a small size.

As shown in FIG. 3, the barrier ribs 190 may be formed between the semiconductor light emitting devices 150. In this case, the barrier ribs 190 may separate the 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 can form the partition.

Also, if the base member of the anisotropic conductive film is black, the barrier 190 may have a reflection characteristic and a contrast may be increased without a separate black insulator.

As another example, the barrier ribs 190 may be provided separately from the reflective barrier ribs. In this case, the barrier rib 190 may include a black or white insulation depending on the purpose of the display device. When a barrier of a white insulator is used, an effect of enhancing reflectivity may be obtained. When a barrier of a black insulator is used, a contrast characteristic may be increased while having a reflection characteristic.

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 converts 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 an individual pixel.

That is, a red phosphor 181 capable of converting blue light into red (R) light can be laminated on the blue semiconductor light emitting element at a position forming a red unit pixel, and at a position forming a green unit pixel, A green phosphor 182 capable of converting blue light into green (G) light can be laminated on the semiconductor light emitting element. Further, only the blue semiconductor light emitting element can be used solely in the portion constituting the blue unit pixel. In this case, the unit pixels of red (R), green (G), and blue (B) can form one pixel. More specifically, phosphors 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. In other words, red (R), green (G), and blue (B) may be arranged in order along the second electrode 140, thereby realizing a unit pixel.

(R), green (G), and blue (B) unit pixels may be implemented by combining the semiconductor light emitting device 150 and the quantum dot QD instead of the fluorescent material. 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 can improve the contrast of light and dark.

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

5A, each of the semiconductor light emitting devices 150 is formed of gallium nitride (GaN) as a main material, and indium (In) and / or aluminum (Al) are added together to form a high output Emitting device.

In this case, the semiconductor light emitting devices may be red, green, and blue semiconductor light emitting devices to form a unit pixel (sub-pixel), respectively. For example, red, green, and blue semiconductor light emitting elements R, G, and B are alternately arranged, and red, green, and blue unit pixels Form a single pixel, through which a full color display can 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, a red phosphor layer 181, a green phosphor layer 182, and a blue phosphor layer 183 may be provided on the white light emitting element W to form a unit pixel. Further, a unit pixel can be formed by using a color filter in which red, green, and blue are repeated on the white light emitting element W.

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

Referring again to this example, the semiconductor light emitting device is disposed on the conductive adhesive layer, and constitutes a unit pixel in the display device. Since the semiconductor light emitting device is excellent in luminance, individual unit pixels can be formed with a small size.

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

Also, even if a square semiconductor light emitting device 150 having a length of 10 m on one side is used as a unit pixel, sufficient brightness for forming a display device appears.

Therefore, when the size of the unit pixel is a rectangle pixel having one side of 600 mu m and the other side of 300 mu m as an example, the distance of the semiconductor light emitting element becomes relatively large.

Therefore, in such a case, a flexible display device having a high image quality higher than the HD picture quality can be realized.

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

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

6, a conductive adhesive layer 130 is first formed on the insulating layer 160 on which the auxiliary electrode 170 and the second electrode 140 are located. A first electrode 120, an auxiliary electrode 170, and a second electrode 140 are formed on the wiring substrate, and the insulating layer 160 is formed on the first substrate 110 to form a single substrate (or a wiring substrate) . In this case, the first electrode 120 and the second electrode 140 may be arranged in mutually orthogonal directions. In addition, the first substrate 110 and the insulating layer 160 may include glass or polyimide (PI), respectively, in order to implement a flexible display device.

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

Next, the second substrate 112, which corresponds to the positions of the auxiliary electrode 170 and the second electrodes 140 and on which the plurality of semiconductor light emitting elements 150 constituting the individual pixels are located, 150 are disposed so as to face the auxiliary electrode 170 and the second electrode 140.

In this case, the second substrate 112 is a growth substrate for growing the semiconductor light emitting device 150, and may be a spire 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 at which a display device can be formed.

Then, the wiring substrate and the second substrate 112 are thermally bonded. For example, the wiring board and the second board 112 can be thermally compressed by applying an ACF press head. The wiring substrate and the second substrate 112 are bonded by the thermocompression bonding. Only the portion between the semiconductor light emitting device 150 and the auxiliary electrode 170 and the second electrode 140 has conductivity due to the characteristics of the anisotropic conductive film having conductivity by thermocompression, The device 150 may be electrically connected. At this time, the semiconductor light emitting device 150 is inserted into the anisotropic conductive film, and partition walls may be formed between the semiconductor light emitting devices 150.

Then, the second substrate 112 is removed. For example, the second substrate 112 may be removed using a laser lift-off method (LLO) or a chemical lift-off method (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 a wiring substrate on which the semiconductor light emitting device 150 is coupled with silicon oxide (SiOx) or the like.

Further, 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 for emitting blue (B) light, and a red phosphor or a green phosphor for converting the blue (B) A layer can be formed on one surface of the device.

The manufacturing method and structure of the display device using the semiconductor light emitting device described above can be modified into various forms. For example, a vertical semiconductor light emitting device may be applied to the display device described above.

In the modifications or embodiments described below, the same or similar reference numerals are given to the same or similar components as those of the previous example, and the description is replaced with the first explanation.

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

Referring to these drawings, the display device may be a display device using a passive matrix (PM) 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. The substrate 210 may include polyimide (PI) to implement a flexible display device. In addition, any insulating and flexible material may be used.

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

A conductive adhesive layer 230 is formed on the substrate 210 on which the first electrode 220 is located. The conductive adhesive layer 230 may be formed of an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing a conductive particle, or the like, as in a display device to which a flip chip type light emitting device is applied. ) And the like. However, the present embodiment also exemplifies the case where the conductive adhesive layer 230 is realized by the anisotropic conductive film.

If the semiconductor light emitting device 250 is connected to the semiconductor light emitting device 250 by applying heat and pressure after the anisotropic conductive film is positioned in a state where the first electrode 220 is positioned on the substrate 210, And is electrically connected to the electrode 220. In this case, the semiconductor light emitting device 250 may be disposed on the first electrode 220.

As described above, the electrical connection is generated because heat and pressure are applied to the anisotropic conductive film to partially conduct in the thickness direction. Therefore, in the anisotropic conductive film, it is divided into a portion having conductivity in the thickness direction and a portion having no conductivity.

In addition, since the anisotropic conductive film contains an adhesive component, the conductive adhesive layer 230 realizes electrical connection as well as mechanical bonding between the semiconductor light emitting element 250 and the first electrode 220.

Thus, 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 can be formed with a small size. The size of the individual semiconductor light emitting device 250 may be, for example, 80 mu m or less on one side and may be a rectangular or square device. In the case of a rectangle, for example, the size may be 20 X 80 μm or less.

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

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

9, the vertical type semiconductor light emitting device includes a p-type electrode 256, a p-type semiconductor layer 255 formed on the p-type electrode 256, 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 p-type electrode 256 located at the bottom may be electrically connected to the first electrode 220 by the conductive adhesive layer 230, and the n-type electrode 252 located at the top may be electrically connected to the second electrode 240 As shown in FIG. Since the vertical semiconductor light emitting device 250 can arrange the electrodes up and down, it has a great advantage that the chip size can be reduced.

Referring to FIG. 8 again, a phosphor layer 280 may be formed on one side 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) . 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 can be laminated on the blue semiconductor light emitting element at a position forming a red unit pixel, and in a position forming a green unit pixel, A green phosphor 282 capable of converting blue light into green (G) light can be laminated on the semiconductor light emitting element. Further, only the blue semiconductor light emitting element can be used solely in the portion constituting the blue unit pixel. In this case, the unit pixels of red (R), green (G), and blue (B) can form one pixel.

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

The second electrode 240 is located between the semiconductor light emitting devices 250 and electrically connected to the semiconductor light emitting devices 250. For example, the semiconductor light emitting devices 250 may be disposed in a plurality of rows, and the second electrode 240 may be disposed between the columns of the semiconductor light emitting devices 250.

The second electrode 240 may be positioned between the semiconductor light emitting devices 250 because the distance between the semiconductor light emitting devices 250 forming the individual pixels is sufficiently large.

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

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 as an ohmic electrode for ohmic contact, and the second electrode covers at least a part of the ohmic electrode by printing or vapor deposition. Accordingly, the second electrode 240 and the n-type electrode of the semiconductor light emitting device 250 can be electrically connected.

Referring again to FIG. 8, the second electrode 240 may be positioned on the conductive adhesive layer 230. A transparent insulating layer (not shown) containing silicon oxide (SiOx) or the like 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 spaced apart from the conductive adhesive layer 230 or the transparent insulating layer.

If a transparent electrode such as ITO (Indium Tin Oxide) is used for positioning the second electrode 240 on the semiconductor light emitting device 250, the problem that the ITO material has poor adhesion with the n-type semiconductor layer have. Accordingly, the present invention has an advantage in that the second electrode 240 is positioned between the semiconductor light emitting devices 250, so that a transparent electrode such as ITO is not used. Therefore, the light extraction efficiency can be improved by using a conductive material having good adhesiveness with the n-type semiconductor layer as a horizontal electrode without being bound by transparent material selection.

Referring again to FIG. 8, the barrier ribs 290 may be positioned between the semiconductor light emitting devices 250. That is, the barrier ribs 290 may be disposed between the vertical semiconductor light emitting devices 250 to isolate the semiconductor light emitting devices 250 forming the individual pixels. In this case, the barrier ribs 290 may separate the individual unit pixels from each other, and may be formed integrally 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 can form the partition.

Also, if the base member of the anisotropic conductive film is black, the barrier ribs 290 may have a reflection characteristic and a contrast may be increased without a separate black insulator.

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

If the second electrode 240 is directly disposed on the conductive adhesive layer 230 between the semiconductor light emitting devices 250, the barrier ribs 290 may be formed between the vertical semiconductor light emitting device 250 and the second electrode 240 As shown in FIG. Therefore, individual unit pixels can be formed with a small size by using the semiconductor light emitting device 250, and the distance between the semiconductor light emitting device 250 can be relatively large enough so that the second electrode 240 can be electrically connected to the semiconductor light emitting device 250 ), And it is possible to realize a flexible display device having HD picture quality.

Further, as shown in FIG. 8, a black matrix 291 may be disposed between the respective phosphors to improve the contrast. That is, this black matrix 291 can improve the contrast of light and dark.

In the display device using the semiconductor light emitting device of the present invention described above, the semiconductor light emitting device grown on the wafer is arranged on the wiring substrate as a flip chip type and used as individual pixels.

Therefore, there is a problem that it is difficult to realize a large screen display due to the size limitation of the wafer. Other embodiments of the present invention for solving such problems will be described in detail below with reference to FIGS. 10 to 19. Furthermore, for example, a display device to which a vertical type semiconductor light emitting device self-assembled in a fluid is applied will be described with reference to the drawings, but the scope of the present invention is not necessarily limited thereto.

10 is a view illustrating a process of manufacturing a substrate 1000 having an assembly groove for assembling the semiconductor light emitting device according to another embodiment of the present invention.

As shown in FIG. 10, the substrate 1000 has an assembly groove such that the semiconductor light emitting device self-assembles into a substrate prepared in the fluid.

The self-assembly method refers to a process in which a plurality of semiconductor light emitting devices grown on a wafer are separated into individual devices and dispersed in a fluid, and then assembled on a substrate using an electromagnetic field.

The semiconductor light emitting device may be a horizontal type semiconductor light emitting device or a vertical type semiconductor light emitting device.

However, since the n-electrode and the p-electrode are formed on the same surface, it is difficult to reduce the sizes of the individual devices formed on the wafer.

In the case of the vertical type semiconductor light emitting device, there is an advantage in that the sizes of devices manufactured on the wafer can be reduced. However, since the n electrode and the p electrode must be disposed on the upper and lower surfaces, And there is a problem that the incidence of defects is relatively high.

Therefore, a display device and a manufacturing method capable of solving the above-described complicated process problems while using a vertical type semiconductor light emitting device are required for a display device of a large screen of a large screen, which requires a reduction in manufacturing cost.

10, the assembly groove 1050 has a shape corresponding to a side portion of the vertical type semiconductor light emitting device so that the vertical type semiconductor light emitting device is arranged in the horizontal direction on the substrate.

First, a substrate 1010 is selected, an assembly electrode 1020 is disposed on the substrate 1010, and an insulating layer 1030 and a barrier rib 1030 are formed on the assembly electrode 1020. [ (1040).

The substrate 1010 may be a flexible substrate. For example, to implement a flexible display device, the substrate 1010 may include, for example, glass or polyimide (PI). In addition, any insulating material such as PEN (polyethylene naphthalate) and PET (polyethylene terephthalate) may be used as long as it is insulating and flexible. Further, the substrate 1010 may be either a transparent material or an opaque material.

The assembly electrode 1020 formed on the substrate 1010 is disposed to induce a dielectrophoresis (DEP) phenomenon due to an electric field during self-assembly.

The assembly electrode 1020 may be formed of, for example, a transparent electrode (ITO), a single layer of molybdenum, or a multilayer structure of molybdenum and aluminum, or may be formed using other general materials.

The assembling electrode 1020 may correspond to a pair of assembling electrodes for fixing the assembled vertical semiconductor light emitting device by forming an electric field as voltage is applied. The gap between the assembly electrodes 1020 is formed to be smaller than the width of the vertical type semiconductor light emitting device and the width of the assembly groove 1050 so that the assembly position of the vertical type semiconductor light emitting device using the electric field can be more accurately fixed.

An insulating layer 1030 is formed on the assembling electrode 1020 so that the assembling electrode 1020 is protected from the fluid and leakage of the current flowing through the assembling electrode 1020 can be prevented. For example, the insulating layer 1030 may be formed of a single layer or a multilayer of an inorganic insulator such as silica, alumina, or the like, or an organic insulator. The insulating layer 1030 may have a minimum thickness to prevent damage to the assembled electrode 1020 in assembling the vertical type semiconductor light emitting device and may have a maximum thickness for stably assembling the vertical type semiconductor light emitting device .

A barrier rib 1040 may be formed on the insulating layer 1030. A portion of the barrier rib 1040 may be located on top of the assembly electrode 1020 and the remaining region may be on the top of the substrate 1010.

For example, when the substrate 1010 is manufactured, part of the barrier ribs formed on the entire upper surface of the insulating layer 1040 may be removed so that the assembly groove 1050, in which each vertical semiconductor light emitting device is coupled to and assembled with the substrate 1010, Can be formed.

The assembly groove 1050 may be formed by photolithography by coating a photosensitive material. Alternatively, glass, SOG (Spin On Glass) or a polymer material is first coated on the substrate for display, a photosensitive material is coated, and a pattern is formed by a photolithography method. Dry etching or wet etching is performed and the photosensitive material is removed.

FIG. 11 is a view of a method of arranging the assembled electrode 1020 included in the substrate of FIG. 10 and the additionally formed metal layers 1110 and 1120.

The assembly electrodes 1020 may be provided in pairs in order to generate an electric field, but the positions where the assembly electrodes are disposed may be different.

11 (a) shows a structure in which a pair of assembly electrodes 1020 are disposed on both sides of one side of an assembly groove. An electric field is generated due to a voltage difference between the assembled electrodes. The applied voltage means an AC voltage. An induced dipole is generated in the dielectric by the AC voltage, and the device can be fixed to the substrate by the DEP force.

11 (b) shows a structure in which one assembling electrode is disposed under one assembly groove. And a voltage difference is generated in relation to an assembled electrode disposed at the lower part of another assembled groove. The number of assembled electrodes can be reduced as compared with the case of FIG. 11 (a).

11 (c) shows a structure including the metal layer 1110 on the partition wall 1040. In FIG. The metal layer 1110 serves to shield an electric field generated in the assembled electrode, thereby helping the electric field generated in the assembled electrode to be formed only in the assembly groove.

The metal layer may be formed between the insulating layer and the barrier ribs or may be formed on the barrier ribs.

11 (d) shows a structure in which the metal layer 1120 is formed only on the upper part of the barrier ribs.

The metal layer may be, for example, a metal thin film such as aluminum (Al) or copper (Cu).

12 is a view schematically showing the structure of a vertical type semiconductor light emitting device 1200 assembled to the substrate of FIG.

12, the vertical semiconductor light emitting device 1200 includes a first semiconductor layer 1210, an active layer 1220 formed on the first semiconductor layer 1210, a second semiconductor layer 1220 formed on the active layer 1220, A semiconductor layer 1230, a magnetic layer 1240 formed on the second semiconductor layer 1230, and a second electrode 1250 formed on the magnetic layer 1240.

The stacked structure of the vertical type semiconductor light emitting device 1200 is a structure that can be formed naturally while the vertical semiconductor light emitting device 1200 is grown on the wafer, and a first electrode connected to the first semiconductor layer is formed through a separate process can do.

Further, the stacked structure of the vertical type semiconductor light emitting device 1200 of FIG. 12 is intended to facilitate understanding of the embodiments disclosed in the present specification, and it should be understood that the present invention is not limited to the above- .

In order to further explain the structural characteristics of the vertical semiconductor light emitting device 1200, the stacking direction is defined as a first direction.

The vertical semiconductor light emitting device 1200 has a lateral length X in the first direction and a first vertical direction and a vertical length Y in the second vertical direction. The transverse length X corresponds to one of a maximum value X1, a minimum value X2 and a value between the maximum value X1 and the minimum value X2, while the longitudinal length Y corresponds to a fixed value Lt; / RTI >

For example, the vertical type semiconductor light emitting device forms an assembly surface 1260 that is flat in the horizontal direction with respect to the first direction. The assembly surface 1260 has a shape corresponding to the lower portion of the assembly groove 1050 formed in the substrate of FIG. 10, so that the assembly surface 1260 can be seated in the lower portion of the assembly groove 1050 .

That is, the side surface portion of the vertical type semiconductor light emitting device 1200 becomes the assembly surface 1260 and assembles in the horizontal direction with the substrate.

The reason why the horizontal length X corresponds to any one of the maximum value X1, the minimum value X2 and the maximum value X1 to the minimum value X2 is that the vertical semiconductor light emitting device 1200 The first semiconductor layer 1210 and the second semiconductor layer 1230 are separated from each other when assembled in the assembly groove 1050.

For example, if the lateral length of the first semiconductor layer 1210 is longer than the lateral length 1230 of the second semiconductor layer, the vertical semiconductor light emitting device has a T- The second semiconductor layer 1230 can be distinguished. Accordingly, even when the substrate is self-assembled to the substrate, it can be assembled with a certain directionality.

However, when the transverse length X does not change and has a fixed value, the first semiconductor layer 1210 and the second semiconductor layer 1230 (refer to FIG. 12) are formed on the assembly surface 1260 of the vertical semiconductor light- It is difficult to distinguish between the two.

Therefore, in the display device in which the vertical semiconductor light emitting device 1200 is to be assembled in the assembly groove 1250 at random and a plurality of semiconductor light emitting devices are arranged in a matrix form, .

Therefore, the vertical type semiconductor light emitting device 1200 has at least two lateral length values X1 and X2 and a fixed vertical length Y, so that the vertical type semiconductor light emitting device 1200 can be assembled at the upper and lower portions in the first direction Of the assembly surface.

Another purpose of changing the transverse length X is to make the shape different depending on the type of the semiconductor light emitting device. In order to implement a display device, red (R), green (G), and blue (B) light emitting devices are required, and they must be precisely assembled according to the respective types. If the shape of the devices and the corresponding mounting grooves of the substrate can be provided, accurate assembly according to the type of device can be performed in the self-assembly process.

It is a further feature of the present invention that the difference between the maximum value X1 and the minimum value X2 of the transverse length X is determined in consideration of the dielectrophoresis (DEP) phenomenon by the electric field .

Dielectrophoresis is a method in which dielectric particles induce an induced dipole in a non-uniform electric field, and the dielectric particles are moved using the force generated thereby.

As described above, the vertical type semiconductor light emitting device 1200 may have two mounting surfaces 1260. A gap is formed between the lower surface of the mounting groove 1050 and the lower surface of the mounting groove 1050 according to the difference between the maximum value X1 and the minimum value X2. If the gap is larger than the effective distance at which the DEP force acts, the remaining surface can not be assembled into the mounting groove.

The effective distance at which the DEP force acts is, for example, within 200 nm. Therefore, the vertical semiconductor light emitting device 1200 is assembled only on the assembly surface 1260 as a result of experimentally making a difference between the maximum value X1 and the minimum value X2 within the range of 200 nm to 20 μm. The difference is assumed to be a structure in which a part of the vertical type semiconductor light emitting device protrudes only in one direction. If the vertical type semiconductor light emitting device has a T-shaped structure symmetrical with respect to the stacking direction, It is desirable to fabricate the semiconductor device in a range of between.

In a display device in which the position of a unit pixel needs to be precisely controlled, when assembled on the remaining surface other than the assembly surface 1260, it is connected immediately to a defect, so it is very important to assemble only the assembly surface. Therefore, there is a technical effect that the defective rate can be largely reduced at the time of designing as described above.

12, the first semiconductor layer 1210 and the second semiconductor layer 1230 may be semiconductor layers of different kinds and may be n or p type semiconductor layers.

For example, if the first semiconductor layer 1210 is an n-type semiconductor layer, the second semiconductor layer is a p-type semiconductor layer.

Each of the n-type semiconductor layer and the p-type semiconductor layer is made of gallium nitride (GaN) or gallium arsenide (GaAs) as a main material and a material such as indium (In) can do.

The magnetic layer 1240 may include a metal having magnetic properties such as Ni. In FIG. 12, the magnetic layer 1240 is disposed on the second semiconductor layer 1230, The position of the magnetic layer 1240 may be changed according to the manufacturing method of the vertical type semiconductor light emitting device 1200.

Since the vertical semiconductor light emitting device 1200 includes the magnetic layer 1240, the vertical semiconductor light emitting device 1200 can move toward the substrate in the fluid due to the magnetic field during self-assembly.

The vertical semiconductor light emitting device 1200 may further include a first electrode and a passivation layer.

The first electrode may be connected to the first semiconductor layer 1210. For this purpose, the vertical semiconductor light emitting device 1200 grown on the wafer must be separated from the wafer and a separate electrode forming process must be performed.

The passivation layer may be formed to surround the upper surface and side surfaces of the vertical type semiconductor light emitting device 1200. Since the passivation layer is formed in a state where the vertical semiconductor light emitting device 1200 is connected to the wafer, a passivation layer may not be formed on the bottom surface of the vertical semiconductor light emitting device 1200.

The passivation layer may be formed of an inorganic insulator such as silica or alumina through plasma enhanced chemical vapor deposition (PECVD), low pressure chemical vapor deposition (LPCVD), sputtering, or the like, or may be formed of a photoresist, Or by spin coating.

13 is a plan view of various shapes that the vertical semiconductor light emitting device 1200 of FIG. 12 can have. The plan view is observed from above in the direction in which the vertical semiconductor light emitting devices 1200 are stacked.

13, the vertical semiconductor light emitting device has a mesa structure or a T-shaped structure in which a second semiconductor layer and a second electrode 1250 protrude from the first semiconductor layer 1210.

For example, the shape and size of the mesa may be a square or a rectangle having a width and a length of 20 mu m or less. The shape and size of the mesa may have various shapes such as a circle or an ellipse having a diameter of 20 탆 or less.

In the case of growing the vertical type semiconductor light emitting device 1200 on the wafer, a shape as shown in FIG. 13 can be obtained by using dry etching or wet etching.

However, the present invention is not limited to the T-shaped or mesa structure expressed by the embodiments. As described above, various shapes other than the T-shaped structure can be derived by adjusting the value of the transverse length X.

14 is a plan view and a cross-sectional view of the substrate 1000 having the mounting groove of Fig.

The mounting groove 1050 formed by the partition 1040 has a T shape, which corresponds to the shape of the side surface of the vertical semiconductor light emitting device 1200 of FIG.

14 (b) is a cross-sectional view taken along line E-E in Fig. 14 (a). An assembly electrode and an insulating layer 1030 are formed on a substrate 1010, and a barrier rib 1040 is disposed thereon.

The width of the assembly groove 1050 formed by the partition 1040 is slightly larger than the width of the assembly surface of the vertical type semiconductor light emitting device. For example, the difference between the width of the assembly groove 1050 and the width of the assembly surface of the vertical type semiconductor light emitting device may be within a range of 3 μm. If the difference in width is too small, the accuracy of the assembly position can be improved. However, since it takes a long time until the vertical type semiconductor light emitting device is assembled into the assembly groove 1050, .

The height of the partition wall 1040 or the depth of the fitting groove 1050 is formed within a range of, for example, within two times the height of the fixed longitudinal length Y represented in FIG.

If the height of the barrier ribs 1040 is too high, the vertical semiconductor light emitting device may be trapped in the assembly groove 1050 even at a position other than the assembly surface 1260 of the vertical semiconductor light emitting device.

Therefore, for example, the height of the barrier ribs 1040 is preferably 500 nm or less.

FIG. 15 is a view schematically showing a process of assembling the vertical semiconductor light emitting device 1200 of FIG. 12 on a substrate 1000 having an assembly groove of FIG.

If the vertical semiconductor light emitting device 1200 is assembled on a surface other than the assembly surface 1260, the probability of failure in the subsequent process is high. Thus, the vertical semiconductor light emitting device 1200 is assembled only on the assembly surface , And should not be assembled on the other side.

As shown in FIG. 15, it can be confirmed that when attempting to assemble the other side surface of the vertical semiconductor light emitting device 1201 other than the flat mounting surface 1260, it is not precisely assembled into the mounting groove.

In addition, even if the vertical semiconductor light emitting device has a flat surface, the vertical semiconductor light emitting device can not be stably assembled into the mounting groove unless it has a structure corresponding to the mounting groove.

For example, the surface of the vertical semiconductor light emitting device 1202 on which the first semiconductor layer is located is flat, but is considerably smaller than the shape of the mounting groove, so that the DEP force is not acted strongly and is difficult to fix.

The reason can be found in the principle of the self-assembly method used in the present invention. The self-assembly of the present invention places the substrate at the top within the fluid, and the assembly groove directs to the bottom of the fluid, i.e., the ground. Therefore, even if the semiconductor light emitting device is attracted to the substrate by the magnetic field, if the DEP force acting on the device is not strong, the device is not fixed to the mounting groove of the substrate but returns to the fluid by gravity.

Referring to FIG. 15, when the mounting surface of the vertical semiconductor light emitting device 1203 is seated in the mounting groove of the substrate, it can be easily fixed by the DEP force.

FIG. 16 is a view showing an adhesive layer 1610 for fixing the vertical semiconductor light emitting device 1200 to the substrate 1000 having the mounting groove of FIG.

The adhesive layer 1610 may be an organic material such as PDMS (Polydimethylsiloxane), PET (Polyethylene Terephthalate), or polyurethane film.

As described above, in one embodiment of the present invention, the vertical type semiconductor light emitting device 1200 is assembled and fixed to the assembly groove 1050 in an electromagnetic field manner, and is not physically or chemically assembled.

Therefore, the vertical semiconductor light emitting device may be moved or separated due to an external impact in the assembly process and the subsequent process.

As shown in FIG. 16, the adhesive layer 1610 may be positioned inside the assembly groove 1050 to stably fix the vertical semiconductor light emitting device after self-assembly.

16 (a) is a plan view for showing the position of the adhesive layer 1610, and FIG. 16 (b) is a sectional view taken along the line F-F in FIG. 16 (a).

The adhesion layer 1610 is formed to be thin, for example, several hundreds of nm, and does not directly affect the DEP force acting by the assembling electrode 1020. [

FIG. 17 is a view of the substrate 1000 having the mounting groove of FIG. 10 including the reflective films 1710 and 1720 on the upper part thereof.

The reflective films 1710 and 1720 are formed at or near the portions where the active layers of the vertical type semiconductor light emitting devices contact the assembly grooves 1050.

As described above, the side surface portion of the vertical type semiconductor light emitting device corresponds to an assembly surface. When the vertical type semiconductor light emitting device is driven, light emitted from the side surface of the active layer is implemented as a pixel.

In the case of a normal vertical semiconductor light emitting element, light emission from the front side of the active layer is used, whereas in the present invention, side emission of the active layer is used, and reflection films 1710 and 1720 are formed near the active layer .

17 (a) is a plan view for showing the positions of the reflective films 1710 and 1720, and FIG. 17 (b) is a sectional view taken along the line G-G in FIG. 17 (a).

As shown in FIG. 17B, the reflective layer may be formed by forming a reflective layer 1710 after applying an insulating layer and forming a barrier rib thereafter There is a way.

As another method of forming the reflective film, there is a method of forming a reflective film 1720 on a part of the folded barrier ribs and a portion where the active layer abuts the assembly groove after the assembly groove 1050 is formed on the substrate.

As the reflective film, for example, a metal reflective film such as silver (Ag) or aluminum (Al) can be used.

Apart from FIG. 17, in the present invention, an Omni-Directional Reflective (ODR) layer may be formed without forming the reflective layer. The ODR layer maintains high reflectivity for a wide angle of incidence as compared to a metal reflective film.

The ODR layer generally has a structure of a semiconductor layer, a dielectric layer, and a metal layer. In the present invention, the ODR layer includes an insulating layer contacting the active layer, which is a light emitting region of the vertical semiconductor light emitting device, Lt; RTI ID = 0.0 > ODR < / RTI > layer.

That is, if the semiconductor layer including the active layer 1220, the insulating layer, and the assembled electrode are designed to be possible as the ODR layer, the reflection efficiency of the lateral light emission of the vertical type semiconductor light emitting device can be enhanced.

FIG. 18 is a diagram showing electrode pads 1810 and 1820 formed on the vertical semiconductor light emitting device 1200 assembled according to the embodiment of FIGS. 10 and 12.

The electrode pad may further be subjected to a wiring process for connecting metal wires thereafter, or may be used for connecting to the corresponding wiring through a wiring board prepared in advance.

18 (a) is a plan view in which the vertical type semiconductor light emitting device 1200 is assembled to a substrate 1000 on which an assembly groove is formed, and FIG. 18 (b) to be.

In the vertical semiconductor light emitting device 1200, the first semiconductor layer and the second semiconductor layer are arranged in a line in a horizontal direction on the substrate, so that the first electrode pad 1810 electrically connects the first semiconductor layer And the second electrode pad 1820 is for electrically connecting the second semiconductor layer.

In addition, the process of forming the first electrode pad 1810 and the second electrode pad 1820 may be performed by only one photo process.

For example, after the vertical semiconductor light emitting device 1200 is assembled on the substrate 1000 having the mounting groove, a planarization process may be performed on the device and the substrate. The planarization process is a process of forming a planarization layer, and the planarization layer may be formed of a photosensitive compound (PAC) or the like.

Thereafter, a part of the planarization layer may be removed so as to be exposed to the outside in order to electrically connect the first semiconductor layer and the second semiconductor layer to the respective wirings.

That is, it is possible to create a trench for forming a via electrode between the planarization layer and the semiconductor layer or between the electrodes formed on the respective semiconductor layers. In this case, the level difference between the upper surface of the flattening layer and the electrode formed on each semiconductor layer or each semiconductor layer is the same according to the assembled structure of the present invention. Therefore, the trench can be formed by performing one photo process and an etching process.

On the other hand, in the case of the horizontal type semiconductor light emitting device, the photolithography process must be separately performed to form n-type and p-type electrodes. Although the n-type semiconductor layer and the p-type semiconductor layer are located on the same plane, the photolithography process and the etching process can be performed for each of the n-type and p-type semiconductor layers because the step difference between the upper portion of the planarization layer and the semiconductor layers is different.

Further, in the case of the horizontal flat type semiconductor light emitting device, the interval between the n-type and the p-type electrode becomes closer as the size of the device becomes smaller in the electrode formation process, and the risk of short is large.

On the other hand, in the case of the present invention, the n-type and p-type electrode intervals may be proportional to the vertical length (lamination direction) of the vertical type semiconductor light emitting device. Accordingly, it is possible to further secure a margin corresponding to the vertical length, thereby eliminating the problem that a defect such as a short circuit occurs in a subsequent process.

Fig. 19 is a cross-sectional view of a display device manufactured according to the embodiment of Figs. 10 and 12. Fig.

The substrate on which the assembly groove of the present invention is formed may be a donor substrate for transferring a light emitting device to another substrate, but a panel substrate for direct use in a display device may also be used.

In the case of the panel substrate, a transistor 1910 for driving an active matrix (AM) may be separately provided. A wiring line 1920 electrically connected to the first-type semiconductor layer and a second- A wiring line 1930 for electrically connecting the transistor 1910, and the like.

Therefore, after the semiconductor light emitting device is assembled horizontally on the panel substrate, the display device can be manufactured by performing the wiring process through the planarization process and the trench formation.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments.

The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100: display device 1010: substrate
1020: Assembly electrode 1030: Insulating layer
1040: barrier rib 1200: vertical type semiconductor light emitting element

Claims (17)

Forming an assembled electrode on a substrate;
Applying an insulating layer to the substrate on which the assembly electrode is formed;
Forming an assembly groove including a barrier rib on the substrate coated with the insulating layer;
Providing an LED having an assembly surface corresponding to the assembly groove; And
Assembling the assembly surface of the LED into the assembly groove,
Wherein providing the LED comprises:
The method of claim 1, further comprising: stacking the first electrode, the first semiconductor layer, the active layer, the second semiconductor layer, and the second electrode in a first direction, wherein the assembly surface is formed in a second direction corresponding to the stacked first direction Wherein the first and second substrates are bonded to each other. The method according to claim 1,
Wherein the second direction is a horizontal direction in the stacked first direction. The method according to claim 1,
Wherein assembling the assembly surface of the LED into the assembly groove comprises:
Contacting an assembly surface of the LED with the assembly groove using an assembly device having a magnetic body; And
And assembling the assembly surface of the LED into the assembly groove based on an electric field applied through the assembly electrode formed on the substrate. The method of claim 3,
Wherein the LED comprises:
The LED having a lateral length (X) in a first direction stacked and a first vertical direction,
Wherein the LED has a vertical length (Y) in a first direction and a second vertical direction in which the LEDs are stacked,
Wherein the horizontal length (X) has at least two different values, and the vertical length (Y) has a fixed value. The method according to claim 1,
Wherein forming the assembly electrode on the substrate comprises:
And forming the assembly electrode as a single assembly electrode so as to be spaced apart from each other so as to overlap the partition walls provided on both sides of the assembly groove or to overlap with the bottom surface of the assembly groove. The method according to claim 1,
Wherein the first semiconductor layer is an N-type GaN layer and the second semiconductor layer is a P-type GaN layer. The method according to claim 1,
RTI ID = 0.0 > 1, < / RTI > wherein the LED comprises a magnetic layer. The method according to claim 1,
Wherein the substrate comprises at least one of glass, a conductor, and a flexible polymer material. The method according to claim 1,
Wherein the step of forming the assembly groove comprises:
And forming a polymer adhesive layer on at least a part of a lower portion of the mounting groove on which the mounting surface of the LED is mounted. The method according to claim 1,
Wherein the step of forming the assembly groove comprises:
And forming a metal reflective film on at least a part of the lower portion of the mounting groove on which the active layer of the LED is mounted. The method according to claim 1,
And simultaneously forming wiring electrodes electrically connected to the first electrode and the second electrode of the LED. The method according to claim 1,
Wherein the LED is a micro-LED having a micrometer size. The method according to claim 1,
Wherein the substrate is provided with a transistor for driving an active matrix. An apparatus comprising at least one LED assembled to a substrate,
Wherein:
An assembling electrode layer in which the assembling electrode is disposed; An insulating layer applied over the assembly electrode; And an assembly groove including a partition wall above the insulating layer,
Wherein the LED comprises:
A first electrode, a first semiconductor layer, an active layer, a second semiconductor layer, and a second electrode are stacked in a first direction,
Wherein the mounting surface is formed in a second direction corresponding to the stacked first direction. 15. The method of claim 14,
And the second direction is a horizontal direction in the stacked first direction. 16. The method of claim 15,
The LED having a lateral length (X) in a first direction stacked and a first vertical direction,
Wherein the LED has a vertical length (Y) in a first direction and a second vertical direction in which the LEDs are stacked,
Wherein the horizontal length (X) has at least two values different from each other, and the vertical length (Y) has a fixed value. 15. The method of claim 14,
Wherein the LED has two surfaces that can be assembled into an upper portion and a lower portion in the first direction when assembled into an assembly groove of the substrate.

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