KR102357645B1 - Display device using semiconductor light emitting device - Google Patents

Abstract

The present invention relates to a display device and a method for manufacturing the same, and more particularly, to a display device using a semiconductor light emitting device. A display device according to the present invention includes a first conductivity type semiconductor layer, a second conductivity type semiconductor layer stacked on the first conductivity type semiconductor layer, and disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer an active layer, an undoped semiconductor layer formed on one surface of the second conductivity type semiconductor layer, wherein at least a portion of the undoped semiconductor layer is recessed toward the second conductivity type semiconductor layer is formed, and a phosphor is filled in the groove.

Description

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

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

Recently, in the field of display technology, a display device having excellent characteristics such as thinness and flexibility has been developed. In contrast, currently commercialized main displays are represented by LCD (Liguid Crystal Display) and AMOLED (Active Matrix Organic Light Emitting Diodes).

However, in the case of LCD, there are problems in that the response time is not fast and flexible implementation is difficult, and in the case of AMOLED, there are weaknesses in that the lifespan is short and the mass production yield is not good.

Meanwhile, a light emitting diode (Light Emitting Diode: LED) is a well-known semiconductor light emitting device that converts electric current into light. It has been used as a light source for display images of electronic devices including communication devices. Accordingly, a method for solving the above problems by implementing a display using the semiconductor light emitting device can be proposed.

One object of the present invention is to provide a structure capable of reducing the manufacturing cost of a semiconductor light emitting device capable of freely realizing colors in a display device in a display device, and a method for manufacturing the same.

A display device according to the present invention includes a plurality of semiconductor light emitting devices, wherein at least one of the semiconductor light emitting devices includes a first conductive semiconductor layer and a second conductive semiconductor layer stacked on the first conductive semiconductor layer. , an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer and an undoped semiconductor layer formed on one surface of the second conductivity type semiconductor layer, wherein the undoped A groove recessed toward the second conductivity type semiconductor layer is formed in at least a portion of the semiconductor layer, and a phosphor is filled in the groove.

In an embodiment, the phosphor includes a bottom portion and a sidewall portion formed along an edge of the undoped semiconductor layer.

In an embodiment, the bottom portion overlaps at least a portion of the second conductivity type semiconductor layer. In addition, the bottom portion is formed on the second conductivity type semiconductor layer.

In an embodiment, the undoped semiconductor layer formed to cover the second conductivity type semiconductor layer may be further provided between the bottom portion and the second conductivity type semiconductor layer.

In an embodiment, at least a portion of the sidewall portion may be surrounded by the undoped semiconductor layer. In addition, the side wall portion is formed to be inclined with respect to a direction perpendicular to the bottom portion.

In an embodiment, the cross-sectional area of the phosphor increases as the distance from the second conductive semiconductor layer increases due to the inclination of the sidewall portion.

In an embodiment, the phosphor includes a quantum dot (QD).

In an embodiment, the first conductivity-type semiconductor layer may be a P-type GaN layer, the second conductivity-type semiconductor layer may be an N-type GaN layer, and the undoped semiconductor layer may be a GaN layer.

In an embodiment, a first conductivity type electrode formed to cover at least a portion of the first conductivity type semiconductor layer and a second conductivity type electrode formed to cover at least a portion of the second conductivity type semiconductor layer are provided.

In the semiconductor light emitting device according to the present invention, a first conductivity type semiconductor layer, a second conductivity type semiconductor layer laminated on the first conductivity type semiconductor layer, and between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer an active layer disposed thereon and an undoped semiconductor layer formed on one surface of the second conductivity type semiconductor layer, wherein at least a portion of the undoped semiconductor layer is recessed toward the second conductivity type semiconductor layer A groove is formed, and a phosphor is filled in the groove.

In the method of manufacturing a display device according to the present invention, the step of growing an undoped semiconductor layer on a substrate, the second conductivity type semiconductor layer, the active layer and the second conductivity type semiconductor layer are stacked sequentially growing a type semiconductor layer, an active layer, and a first conductivity type semiconductor layer, etching the undoped semiconductor layer, the first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer on the substrate Isolating the semiconductor light emitting devices, etching at least a portion of the undoped semiconductor to form a recessed groove, and filling the groove with a phosphor.

In an embodiment, the phosphor of the method of manufacturing a display device includes a quantum dot (QD).

In an embodiment, the steps of forming a first conductivity type electrode to cover at least a portion of the first conductivity type semiconductor layer and forming a second conductivity type electrode to cover at least a portion of the second conductivity type semiconductor layer may include

In the display device according to the present invention, a groove recessed toward the second conductivity type semiconductor layer is formed in the undoped semiconductor layer formed on one surface of the second conductivity type semiconductor layer by a simple process, and the groove A semiconductor light emitting device integrated with the phosphor may be manufactured by charging the phosphor including quantum dots (QD). Accordingly, it is possible to reduce the manufacturing cost of the semiconductor light emitting device capable of freely realizing the color of the semiconductor light emitting device through a simple process.

1 is a conceptual diagram illustrating an embodiment of a display device using a semiconductor light emitting device of the present invention.
FIG. 2 is a partially enlarged view of part A of FIG. 1 , and FIGS. 3A and 3B are cross-sectional views taken along lines BB and CC of FIG. 2 .
4 is a conceptual diagram illustrating the flip chip type semiconductor light emitting device of FIG. 3 .
5A to 5C are conceptual diagrams illustrating various forms of implementing colors in relation to a flip-chip type semiconductor light emitting device.
6 is a cross-sectional view illustrating a method of manufacturing a display device using the semiconductor light emitting device of the present invention.
7 is a perspective view illustrating 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 line DD of FIG. 7 ;
9 is a conceptual diagram illustrating the vertical semiconductor light emitting device of FIG. 8 .
10 is an enlarged view of part A of FIG. 1 for explaining another embodiment of the present invention to which a semiconductor light emitting device of a new structure is applied.
FIG. 11 is a cross-sectional view taken along line EE of FIG. 10 .
12 is a conceptual diagram illustrating a semiconductor light emitting device having a new structure.
13A to 13G are cross-sectional views illustrating a method of manufacturing a semiconductor light emitting device according to the present invention.
14A to 14C are cross-sectional views illustrating a method of manufacturing a display device using the semiconductor light emitting device of the present invention.
15 is a conceptual diagram illustrating a vertical semiconductor light emitting device for explaining another embodiment of the present invention.
16A to 16G are cross-sectional views illustrating a method of manufacturing a display device using the vertical semiconductor light emitting device of the present invention.

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

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

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

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

As illustrated, information processed by the control unit of the display apparatus 100 may be displayed using a flexible display.

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

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

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

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

2 is a partially enlarged view of part 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 showing the flip-chip type semiconductor light emitting device of FIG. 3A, 5A to 5C are conceptual diagrams illustrating various forms of implementing colors in relation to a flip-chip type semiconductor light emitting device.

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

The display device 100 includes a first 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 first substrate 110 may be a flexible substrate. For example, to implement a flexible display device, the first substrate 110 may include glass or polyimide (PI). In addition, any material such as polyethylene naphthalate (PEN) or polyethylene terephthalate (PET) may be used as long as it has insulating properties and is flexible. In addition, the first substrate 110 may be made of either a transparent material or an opaque material.

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

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

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

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 performing a specific function is formed between the insulating layer 160 and the conductive adhesive layer 130 , or the conductive adhesive layer 130 is disposed on the first substrate 110 without the insulating layer 160 . structure is also possible. In a structure in which the conductive adhesive layer 130 is disposed on the first substrate 110 , the conductive adhesive layer 130 may serve as an insulating layer.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

The phosphor layer 180 may be located on the outer surface of the semiconductor light emitting device 150 . For example, the semiconductor light emitting device 150 is a blue semiconductor light emitting device that emits blue (B) light, and the phosphor layer 180 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 an individual pixel.

That is, a red phosphor 181 capable of converting blue light into red (R) light may be stacked on the blue semiconductor light emitting device 151 at a position constituting a unit pixel of red color, and a position constituting a unit pixel of green color In , 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 the portion constituting the blue unit pixel. In this case, unit pixels of red (R), green (G), and blue (B) may form one pixel. More specifically, a phosphor of one color may be stacked along each line of the first electrode 120 . Accordingly, one line in the first electrode 120 may be an electrode for controlling one color. That is, red (R), green (G), and blue (B) may be sequentially disposed along the second electrode 140 , thereby realizing a unit pixel.

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

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

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

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

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

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

Referring to FIG. 5C , a structure in which a red phosphor layer 181 , a green phosphor layer 182 , and a blue phosphor layer 183 are provided on the ultraviolet light emitting device UV is also possible. In this way, the semiconductor light emitting device can be used in the entire region not only for visible light but also for ultraviolet (UV) light, and can be extended to form a semiconductor light emitting device in which ultraviolet (UV) can be used as an excitation source of the upper phosphor. .

Referring back to this example, the semiconductor light emitting device 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 luminance, individual unit pixels can be configured even with a small size. The size of the individual semiconductor light emitting device 150 may have a side length of 80 μm or less, and may be a rectangular or square device. In the case of a rectangle, the size may be 20X80㎛ or less.

In addition, even when a square semiconductor light emitting device 150 having a side length of 10 μm is used as a unit pixel, sufficient brightness to form a display device appears. Accordingly, when the unit pixel is a rectangular pixel having one side of 600 μm and the other side of 300 μm, the distance between the semiconductor light emitting devices is relatively large. Accordingly, in this case, it is possible to implement a flexible display device having HD image quality.

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

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

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 positioned. An insulating layer 160 is laminated on the first substrate 110 to form one substrate (or wiring board), and the wiring substrate includes a first electrode 120 , an auxiliary electrode 170 , and a second electrode 140 . this is placed In this case, the first electrode 120 and the second electrode 140 may be disposed in a mutually orthogonal direction. In addition, in order to implement a flexible display device, the 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, and for this purpose, the anisotropic conductive film may be applied to the substrate on which the insulating layer 160 is positioned.

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

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

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

Then, the wiring board and the second board 112 are thermocompression-bonded. For example, the wiring substrate and the second substrate 112 may be thermocompression-bonded by applying an ACF press head. The wiring substrate and the second substrate 112 are bonded by the thermocompression bonding. Due to the properties of the anisotropic conductive film having conductivity by thermocompression bonding, only the portion between the semiconductor light emitting device 150 and the auxiliary electrode 170 and the second electrode 140 has conductivity, and through this, the electrodes and the semiconductor light emission. The device 150 may be electrically connected. At this time, the semiconductor light emitting device 150 is inserted into the anisotropic conductive film, through which a barrier rib 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 (LLO) method or a chemical lift-off (CLO) method.

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) or the like on the wiring board to which the semiconductor light emitting device 150 is coupled.

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

The manufacturing method or structure of the display device using the semiconductor light emitting device described above may be modified in various forms. As an example, a vertical semiconductor light emitting device may also be applied to the display device described above. 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 components as those of the preceding example, and the description is replaced with the first description.

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

The display device includes a substrate 210 , a first electrode 220 , a conductive adhesive layer 230 , a second electrode 240 , and 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) to implement a flexible display device. In addition, any material that has insulating properties and is flexible may be used.

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

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

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

The electrical connection is created because, as described above, when heat and pressure are applied to the anisotropic conductive film, it partially has conductivity in the thickness direction. Accordingly, the anisotropic conductive film is divided into a conductive portion 231 and a non-conductive portion 232 in the thickness direction.

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

As described above, the semiconductor light emitting device 250 is positioned on the conductive adhesive layer 230 and constitutes individual pixels in the display device through this. Since the semiconductor light emitting device 250 has excellent luminance, individual unit pixels can be configured even with a small size. The size of the individual semiconductor light emitting device 250 may have a side length of 80 μm or less, and may be a rectangular or square device. In the case of a rectangle, the size may be 20X80㎛ or less.

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

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

Referring to FIG. 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 to the first electrode 220 and the conductive adhesive layer 230 , and the upper n-type electrode 252 may be a second electrode 240 to be described later. ) can be electrically connected to. The vertical semiconductor light emitting device 250 has a great advantage in that the size of the chip can be reduced because electrodes can be arranged up and down.

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

That is, a red phosphor 281 capable of converting blue light into red (R) light may be stacked on the blue semiconductor light emitting device 251 at a position constituting a unit pixel of red color, and a position constituting a unit pixel of green color In , 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 the portion constituting the blue unit pixel. In this case, unit pixels of red (R), green (G), and blue (B) may form one pixel.

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

Referring back to this 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 located between the columns of the semiconductor light emitting devices 250 .

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

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

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

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

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

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

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

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

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

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

As described above, the semiconductor light emitting device 250 is positioned on the conductive adhesive layer 230 and constitutes individual pixels in the display device through this. Since the semiconductor light emitting device 250 has excellent luminance, individual unit pixels can be configured even with a small size. Accordingly, a full-color display in which unit pixels of red (R), green (G), and blue (B) constitute one pixel can be implemented by the semiconductor light emitting device.

In the display device of the present invention described above, in a form in which the phosphor is stacked on a semiconductor light emitting device, the constituent materials and manufacturing processes constituting the unit pixels of red (R), green (G), and blue (B), respectively, are mutually exclusive. There is a different problem. Therefore, even in the implementation of the display device, there is a problem that the manufacturing cost is high due to the complicated process.

The present invention proposes a semiconductor light emitting device having a novel structure capable of solving these problems. Hereinafter, a display device to which a semiconductor light emitting device of a new structure in which a phosphor and a semiconductor light emitting device are integrated is applied and a manufacturing method thereof will be described.

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

10 and 11 , as the display device 1000 using the semiconductor light emitting device, the display device 1000 using the passive matrix (PM) type semiconductor light emitting device is exemplified. However, the examples described below are also applicable to an active matrix (AM) type semiconductor light emitting device.

The display apparatus 1000 includes a substrate 1010 , a first electrode 1020 , a charging layer 1030 , a second electrode 1040 , and a plurality of semiconductor light emitting devices 1050 .

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

In addition, the filling layer 1030 may be a white material that can improve light extraction efficiency. In addition, the filling layer 1030 is disposed between the substrate 1010 on which the first electrode 1020 is positioned and the semiconductor light emitting device 1050 to physically contact the first electrode 1020 and the semiconductor light emitting device 1050 . may be Accordingly, the semiconductor light emitting device 1050 and the first electrode 1020 may be electrically connected to each other.

In addition, an adhesive layer 1031 may be further disposed on the filling layer 1030 to bond the semiconductor light emitting device 1050 and the substrate 1010 . The adhesive layer 1031 may be formed of silver paste, tin paste, and solder paste. The list of the adhesive layer 1031 is merely exemplary, and the present invention is not limited thereto.

Furthermore, in the structure in which the filling layer 1030 is disposed, a material through which no current flows may be filled in the gap formed between the semiconductor light emitting devices 1050 .

In another embodiment, the filling layer 1030 may be replaced with the anisotropic conductive film described above. That is, the plurality of semiconductor light emitting devices 1050 are coupled by the anisotropic conductive film, and are electrically connected to the first electrode 1020 and the second electrode 1040 .

In addition, a panel 1060 is disposed on one surface of the semiconductor light emitting device 1050 . The panel 1060 may include a material that passes light such as glass or a polymer material, and may include an adhesive member 1061 for bonding the semiconductor light emitting device 1050 to the panel 1060 .

The adhesive member 1061 can bond the semiconductor light emitting device 1050 and the panel 1060 through a bonding process such as a laminate bonding process, and is provided on the light emitting surface of the semiconductor light emitting device 1050 to minimize optical loss. For this purpose, it is possible to apply a transparent polymer. In addition, since thermal stability sufficient to withstand heat generated during the laminate bonding process is required, polydimethylsiloxane (PDMS) or polymethylphenylsiloxane (PMPS) may be included. The items listed for the adhesive member 1061 are exemplary only, and the present invention is not limited thereto.

12 is a conceptual diagram illustrating a semiconductor light emitting device according to an embodiment of the present invention.

Referring to FIG. 12 , the semiconductor light emitting device 1050 is a semiconductor in which a first conductive electrode 1056 and a second conductive electrode 1052 are disposed in parallel in the same direction as in the flip chip type semiconductor light emitting device described above. It may be a light emitting device. In detail, the first conductive electrode 1056 and the second conductive electrode 1052 of the semiconductor light emitting device 1050 are disposed opposite to the surface on which the visual information is output, and light emitted from the surface on which the visual information is output. may be of a form that can prevent being disturbed by the first conductive type electrode 1056 and the second conductive type electrode 1052 .

The semiconductor light emitting device 1050 includes a first conductivity type electrode 1056 , a first conductivity type semiconductor layer 1055 on which the first conductivity type electrode 1056 is formed, and an active layer formed on the first conductivity type semiconductor layer 1055 . 1054 and a second conductivity type semiconductor layer 1053 formed on the active layer 1054 . In addition, an undoped semiconductor layer 1057 formed on a portion of one surface of the second conductivity type semiconductor layer 1053 and a second conductivity type electrode formed on a portion of the other surface of the second conductivity type semiconductor layer 1053 ( 1052) and a phosphor 1080. That is, the first conductivity type electrode 1056 may be formed to cover at least a portion of the first conductivity type semiconductor layer 1055 , and the second conductivity type electrode 1056 may be formed to cover at least a portion of the second conductivity type semiconductor layer 1053 . An electrode 1052 may be formed.

As illustrated, an active layer 1054 may be disposed between the first conductivity type semiconductor layer 1055 and the second conductivity type semiconductor layer 1053 . The active layer 1054 may be formed to cover the first conductivity type semiconductor layer 1055 . Also, the active layer 1054 may overlap at least a portion of the second conductivity type semiconductor layer 1053 on the other surface of the second conductivity type semiconductor layer 1053 .

In addition, an undoped semiconductor layer 1057 formed on one surface of the second conductivity type semiconductor layer 1053 is included. In the undoped semiconductor layer 1057 , a groove recessed toward the second conductivity type semiconductor layer 1053 is formed, and a phosphor 1080 may be filled in the groove.

In an embodiment, the first conductivity type semiconductor layer 1055 may be a P-type GaN layer, the second conductivity type semiconductor layer 1053 may be an N-type GaN layer, and the undoped semiconductor layer 1057 may be a GaN layer. . However, the present invention is not necessarily limited thereto, and examples in which the first conductivity type is an N-type and the second conductivity type is a P-type are also possible.

The phosphor 1080 may include a bottom portion 1080 ′ and a sidewall portion 1080 ″ formed along a semiconductor edge of the undoped semiconductor layer 1057 .

The bottom portion 1080 ′ of the phosphor 1080 may be disposed on the second conductivity type semiconductor layer 1053 , and may overlap at least a portion of the second conductivity type semiconductor layer 1053 . Furthermore, the area of the bottom portion 1080 ′ may be smaller than the area of one surface of the second conductivity type semiconductor layer 1053 . In addition, an undoped semiconductor layer 1057 formed to cover the second conductivity type semiconductor layer 1053 may be further disposed between the phosphor 1080 and the second conductivity type semiconductor layer 1053 .

In addition, the sidewall portion 1080″ of the phosphor 1080 may be formed such that at least a part thereof is surrounded by the undoped semiconductor layer 1057. In addition, the sidewall portion 1080″ is formed between the bottom portion 1080′ and the bottom portion 1080′. It is made to be inclined with respect to the vertical direction. For example, the phosphor 1080 may be formed to have an increased cross-sectional area as it moves away from the second conductive semiconductor layer 1053 due to the inclination of the sidewall portion 1080″.

In addition, the phosphor 1080 may include a quantum dot (QD) to implement a semiconductor light emitting device that emits red (R), green (G), and blue (B) light. In detail, the phosphor 1080 includes the quantum dot (QD) and a resin of an organic compound, and the bottom portion 1080 ′ is one surface of the second conductive semiconductor layer 1053 or the undoped semiconductor layer 1057 . may be formed on the Accordingly, the phosphor 1080 may be implemented integrally with the semiconductor light emitting device 1050 .

For example, the semiconductor light emitting device 1050 is a blue semiconductor light emitting device that emits blue (B) light, and the phosphor 1080 converts the blue (B) light into a color of a unit pixel. The phosphor 1080 may be a red phosphor constituting an individual pixel or a green phosphor. That is, a red quantum dot (QD) phosphor capable of converting blue light into red (R) light may be included on the blue semiconductor light emitting device at a position constituting the red unit pixel, and light may be emitted in red, and the unit of green color In the position forming the pixel, green light may be emitted by including a green quantum dot (QD) phosphor capable of converting blue light into green (G) light on the blue semiconductor light emitting device. In addition, only the blue semiconductor light emitting device may be used alone in a portion constituting the blue unit pixel. In this case, unit pixels of red (R), green (G), and blue (B) may form one pixel.

That is, the phosphor 1080 including the quantum dot (QD) is integrated so that the color of the semiconductor light emitting device can be freely realized, and units of red (R), green (G), and blue (B) can be achieved by the semiconductor light emitting device. A full-color display in which pixels constitute one pixel may be implemented.

13A to 13G are cross-sectional views illustrating a method of manufacturing the semiconductor light emitting device 1050 of the present invention.

Referring to FIG. 13A , a flip-chip type light emitting device may be formed on a substrate.

For example, in the semiconductor light emitting device, an undoped semiconductor layer 1057 and a second conductivity type semiconductor layer 1053 are stacked on a substrate W, and an undoped semiconductor layer 1053 is formed on the second conductivity type semiconductor layer 1053 . A second conductivity type semiconductor layer 1053, an active layer 1054, and a first conductivity type semiconductor layer 1055 are formed in a portion of the active layer 1054 and a first conductivity type semiconductor layer 1055 formed on the active layer 1054. grow in turn.

Referring back to FIG. 13A , the undoped semiconductor layer 1057 , the first conductivity type semiconductor layer 1055 , the active layer 1054 , and the second conductivity type semiconductor layer 1053 are etched to form a semiconductor on the substrate W Isolating the light emitting elements. Furthermore, the first conductive electrode 1056 is disposed on the first conductive semiconductor layer 1055 , and the first conductive electrode 1056 is horizontally spaced apart from the first conductive electrode 1056 on the second conductive semiconductor layer 1053 . A second conductive type electrode 1052 is included.

In an embodiment, the substrate W is a growth substrate on which semiconductor light emitting devices are grown, and may be a sapphire substrate or a silicon substrate. The enumeration of the substrate W is exemplary only, and the present invention is not limited thereto.

Referring to FIG. 13B , the undoped semiconductor layer 1057 , the second conductivity type semiconductor layer 1053 , the active layer 1054 , the first conductivity type semiconductor layer 1055 , the first conductivity type electrode 1056 and the first conductivity type semiconductor layer 1056 , A laminate bonding process may be performed between the substrate W on which the second conductive electrode 1052 is formed and the support substrate S on which the adhesive member 1071 is formed. Specifically, the semiconductor light emitting devices on the substrate W and the adhesive member 1071 are temporarily bonded.

Then, the semiconductor light emitting devices may be separated from the substrate W by a laser life-off (LLO) or chemical lift-off (CLO) method. In the present invention, the semiconductor light emitting device may be separated using a laser beam.

In an embodiment, the support substrate S may be a polymer substrate having a low coefficient of thermal expansion (CTE) and high thermal resistance, and in detail, the polymer substrate is polyimide (PI, Polyimide) Or silicon (silicone, polysiloxane) may be included. The items listed for the support substrate (S) are only exemplary, and the present invention is not limited thereto.

In addition, the adhesive member 1071 may include polydimethylsiloxane (PDMS) or polymethylphenylsiloxane (PMPS), since thermal stability sufficient to withstand the heat generated during the laminate bonding process is required. The items listed for the adhesive member 1071 are exemplary only, and the present invention is not limited thereto.

Referring to FIG. 13C , the semiconductor light emitting device is bonded to the support substrate S on which the adhesive member 1071 is formed, the substrate W is separated, and then a part of the adhesive member 1071 is removed to emit the semiconductor light. You can expose the small.

Referring to FIG. 13D , a photoresist (PR) 1072 on the adhesive member 1071 and the semiconductor light emitting device in order to etch the undoped semiconductor layer 1057 so that the phosphor 1080, which will be described later, can be charged. ) may be applied and patterned to expose a portion of the undoped semiconductor layer 1057 .

Referring to FIG. 13E , a process of selectively etching the partially exposed undoped semiconductor layer 1057 may be performed. The undoped semiconductor layer 1057 on which the photoresist 1072 is not stacked may be etched. In detail, dry etching using a mixture of boron trichloride (BCl ₃ ), chlorine (Cl ₂ ), and argon (Ar) gas may be performed to selectively etch the undoped semiconductor layer 1057 .

Accordingly, a groove 1058 recessed toward the second conductivity type semiconductor layer 1053 may be formed in at least a portion of the undoped semiconductor layer 1057 , and the undoped semiconductor layer 1057 may be recessed. A ring shape may be formed on the second conductivity type semiconductor layer 1053 along the groove 1058 .

In addition, the groove 1058 may be formed along the bottom and the edge of the second conductive semiconductor layer 1053 to have a sidewall surrounding the bottom, and the sidewall may be inclined in a direction perpendicular to the bottom. have. In detail, the cross-sectional area of the groove 1058 may increase as the distance from the second conductive semiconductor layer 1053 increases due to the inclination of the sidewall portion.

The bottom portion of the groove 1058 may be formed of a second conductivity type semiconductor layer 1053 . Furthermore, an undoped semiconductor layer 1057 formed to cover the second conductivity type semiconductor layer 1053 may be further provided between the bottom of the groove 1058 and the second conductivity type semiconductor layer 1053 .

Referring to FIG. 13F , filling the groove 1058 with the phosphor 1080 may be performed. The phosphor 1080 may include a bottom portion 1080 ′ and a sidewall portion 1080 ″ formed along the semiconductor edge of the undoped semiconductor layer 1057 while being filled in the groove 1058 .

The bottom portion 1080 ′ of the phosphor 1080 may be disposed on the second conductivity type semiconductor layer 1053 , and may overlap at least a portion of the second conductivity type semiconductor layer 1053 . Furthermore, the area of the bottom portion 1080 ′ may be smaller than the area of one surface of the second conductivity type semiconductor layer 1053 . In addition, an undoped semiconductor layer 1057 formed to cover the second conductivity type semiconductor layer 1053 may be further disposed between the phosphor 1080 and the second conductivity type semiconductor layer 1053 .

In addition, the sidewall portion 1080″ of the phosphor 1080 may be formed such that at least a part thereof is surrounded by the undoped semiconductor layer 1057. In addition, the sidewall portion 1080″ is formed between the bottom portion 1080′ and the bottom portion 1080′. It is made to be inclined with respect to the vertical direction. For example, the phosphor 1080 may be formed to have an increased cross-sectional area as it moves away from the second conductive semiconductor layer 1053 due to the inclination of the sidewall portion 1080″.

In detail, the phosphor 1080 forms a mixture including quantum dots (QD) and a resin of an organic compound, and the mixture is prepared by methods such as spray coating, inkjet printing, and dipping. As a result, the groove 1058 may be filled.

In addition, the phosphor 1080 may include a quantum dot (QD) to implement a semiconductor light emitting device that emits red (R), green (G), and blue (B) light. In detail, the phosphor 1080 includes the quantum dot (QD) and a resin of an organic compound, and the bottom portion 1080 ′ is one surface of the second conductive semiconductor layer 1053 or the undoped semiconductor layer 1057 . may be formed on the Accordingly, the phosphor 1080 may be implemented integrally with the semiconductor light emitting device 1050 .

Referring to FIG. 13G , a process of removing the photoresist 1072 after forming the phosphor 1080 may be performed to form the semiconductor light emitting device 1050 .

14A to 14C are cross-sectional views illustrating a method of manufacturing a display device using the semiconductor light emitting device 1050 of the present invention.

Referring to FIG. 14A , in order to manufacture a display device using the semiconductor light emitting device 1050 , the semiconductor light emitting device 1050 may be adhered to the panel 1060 including the adhesive member 1061 . In detail, as the semiconductor light emitting device 1050 and the panel 1060 are bonded through the bonding process such as the bonding process such as the bonding process between the adhesive member 1061 and the laminate, the semiconductor light emitting device 1050 is transferred from the supporting substrate S to the panel 1060. can be transcribed.

That is, the semiconductor light emitting device 1050 is transferred to the panel 1060 , the panel 1060 is disposed on one surface of the semiconductor light emitting device 1050 , and the semiconductor light emitting device 1050 and the panel 1060 are adhered for adhesion. A member 1061 may be included.

The panel 1060 may include a material made of glass or a polymer material that passes light, and since the adhesive member 1061 is provided on the light emitting surface of the semiconductor light emitting device 1050, a transparent polymer to minimize optical loss. applicable. In addition, since thermal stability sufficient to withstand heat generated during the laminate bonding process is required, polydimethylsiloxane (PDMS) or polymethylphenylsiloxane (PMPS) may be included.

Referring to FIG. 14B , a filling layer 1030 for improving light extraction efficiency of a display device including the semiconductor light emitting device 1050 may be filled between the semiconductor light emitting devices 1050 . The filling layer 1030 may be a white material and may be a material capable of improving light extraction efficiency.

Furthermore, after filling the filling layer 1030 , a metal layer with high reflectivity (not shown) is formed on at least a portion of the first conductive electrode 1056 , the second conductive electrode 1052 , and the filling layer 1030 . can do. The metal layer may be a high reflectivity silver (Ag), aluminum (Al), and APC (Ag+Pd+Cu) alloy, and may control optical characteristics of the semiconductor light emitting device 1050 .

Referring to FIG. 14C , the semiconductor light emitting device 1050 and the panel 1060 are bonded, the filling layer 1030 is filled between the semiconductor light emitting devices 1050 , and then the first electrode 1020 and the second electrode It may be adhered to the substrate 1010 on which the 1040 is disposed to form a display device. In detail, an adhesive layer 1031 is further disposed between the substrate 1010 on which the first electrode 1020 and the second electrode 1040 are disposed and the semiconductor light emitting device 1050 , so that the semiconductor light emitting device 1050 and the substrate 1010 are disposed. ) can also be attached.

Meanwhile, the display device using the semiconductor light emitting device described above may be modified in various forms. Hereinafter, such a modified example is demonstrated.

15 is a conceptual diagram illustrating a vertical semiconductor light emitting device 2050 for explaining another embodiment of the present invention.

Referring to FIG. 15 , the vertical semiconductor light emitting device 2050 has a great advantage in that the size of a chip can be reduced because electrodes can be arranged up and down.

However, since the phosphor 2080 is formed by the manufacturing method of FIGS. 13A to 13G described above, the second conductivity type semiconductor layer 2053 is surrounded by the undoped semiconductor layer 2057 , so the second conductivity type semiconductor layer The second conductive type electrode 2052 corresponding to 2053 cannot be directly formed. Accordingly, the second conductive electrode 2052 may be formed in the method of manufacturing a display device using the vertical semiconductor light emitting device 2050 of the present invention in FIGS. 16A to 16C , which will be described later.

In detail, the vertical semiconductor light emitting device 2050 includes a first conductivity type electrode 2056 , a first conductivity type semiconductor layer 2055 on which the first conductivity type electrode 2056 is formed, and a first conductivity type semiconductor layer 2055 . ) formed on the active layer 2054, the second conductivity type semiconductor layer 2053 formed on the active layer 2054, and an undoped semiconductor layer formed on a part of one surface of the second conductivity type semiconductor layer 1053 ( 2057). In addition, a groove recessed toward the second conductivity type semiconductor layer 2053 is formed in at least a portion of the undoped semiconductor layer 2057 , and a phosphor 2080 is filled in the groove.

In addition, the vertical semiconductor light emitting device 2050 may be self-assembled using a method of assembling the semiconductor light emitting device with a wiring board in order to solve a problem in which it is difficult to implement a large screen display due to the size limitation of the wafer. A detailed description of the self-assembly method will be described in detail with reference to FIG. 16C to be described later.

Accordingly, the vertical semiconductor light emitting device 2050 may include a sacrificial layer (not shown) on the other surface of the first conductive electrode 2056 . The sacrificial layer may be a material that can be easily removed in a fluid.

16A to 16G are cross-sectional views illustrating a method of manufacturing a display device using the vertical semiconductor light emitting device 2050 of the present invention.

Referring to FIG. 16A , a vertical semiconductor light emitting device 2050 may be formed on a substrate.

The vertical semiconductor light emitting device 2050 may be manufactured by the same manufacturing method as in FIGS. 13A to 13G described above.

For example, in the semiconductor light emitting device, an undoped semiconductor layer 2057 and a second conductivity type semiconductor layer 2053 are stacked on a substrate, and an active layer is partially formed on the second conductivity type semiconductor layer 2053 . A second conductivity type semiconductor layer 2053 , an active layer 2054 , and a first conductivity type semiconductor layer 2055 are sequentially grown to form a first conductivity type semiconductor layer 2055 formed on the active layer 2054 , 2054 . make it

Further, the undoped semiconductor layer 2057 , the first conductivity type semiconductor layer 2055 , the active layer 2054 , and the second conductivity type semiconductor layer 2053 are etched to isolate the semiconductor light emitting devices on the substrate. Furthermore, a first conductive electrode 2056 is disposed on the first conductive semiconductor layer 2055 to form a portion of the vertical semiconductor light emitting device 2050 .

In an embodiment, the substrate is a growth substrate on which semiconductor light emitting devices are grown, and may be a sapphire substrate or a silicon substrate.

In addition, a sacrificial layer (not shown) may be provided on the other surface of the first conductive electrode 2056 . The sacrificial layer may be a material that can be easily removed from the fluid, and can be easily removed from the fluid in a self-assembly process to be described later and assembled on the substrate 2010 .

Further, the substrate on which the undoped semiconductor layer 2057, the second conductivity type semiconductor layer 2053, the active layer 2054, the first conductivity type semiconductor layer 2055 and the first conductivity type electrode 2056 are formed is adhered. A laminate bonding process may be performed on the support substrate S on which the member 2071 is formed.

Accordingly, the semiconductor light emitting devices on the substrate and the adhesive member 2071 may be temporarily bonded, and the sacrificial layer (not shown) may be disposed between the first conductive electrode 2056 and the adhesive member 2071 . .

Subsequently, the semiconductor light emitting devices may be separated from the substrate by a laser life-off (LLO) or chemical lift-off (CLO) method. In the present invention, the semiconductor light emitting device may be separated using a laser beam.

In addition, after separating the substrate, a portion of the adhesive member 2071 may be removed to expose the semiconductor light emitting device. Furthermore, the undoped semiconductor layer 2057 may be etched so that the phosphor 2080 may be charged. Accordingly, a portion of the undoped semiconductor layer 2057 may be exposed by applying and patterning a photoresist (PR) on the adhesive member 2071 and the semiconductor light emitting device.

A process of selectively etching the partially exposed undoped semiconductor layer 2057 may be performed. The undoped semiconductor layer 2057 on which the photoresist is not stacked may be etched. In detail, dry etching using a mixture of boron trichloride (BCl ₃ ), chlorine (Cl ₂ ), and argon (Ar) gas may be performed to selectively etch the undoped semiconductor layer 2057 .

Accordingly, a groove recessed toward the second conductivity type semiconductor layer 2053 may be formed in at least a portion of the selectively etched undoped semiconductor layer 2057 , and the undoped semiconductor layer 2057 may be A ring shape may be formed on the second conductivity type semiconductor layer 2053 along the recessed groove.

Furthermore, filling the groove with the phosphor 2080 may be performed. The phosphor 2080 may include a bottom portion 2080 ′ and a sidewall portion 2080 ″ formed along the semiconductor edge of the undoped semiconductor layer 2057 while being filled in the groove.

The bottom portion 2080 ′ of the phosphor 2080 may be disposed on the second conductivity type semiconductor layer 2053 , and may overlap at least a portion of the second conductivity type semiconductor layer 2053 . Furthermore, the area of the bottom portion 2080 ′ may be smaller than the area of one surface of the second conductivity type semiconductor layer 2053 . In addition, an undoped semiconductor layer 2057 formed to cover the second conductivity type semiconductor layer 2053 may be further disposed between the phosphor 2080 and the second conductivity type semiconductor layer 2053 .

In addition, the sidewall portion 2080″ of the phosphor 2080 may be formed such that at least a part thereof is surrounded by the undoped semiconductor layer 2057. In addition, the sidewall portion 2080″ includes the bottom portion 2080′ and It is made to be inclined with respect to the vertical direction. For example, due to the inclination of the sidewall portion 2080 ″, the phosphor 2080 may be formed to have an increased cross-sectional area as it moves away from the second conductivity type semiconductor layer 2053 .

In detail, the phosphor 2080 forms a mixture including quantum dots (QD) and a resin of an organic compound, and the mixture is prepared by methods such as spray coating, inkjet printing, and dipping. As a result, the groove 2058 may be filled.

In addition, the phosphor 2080 may include a quantum dot (QD) to implement a semiconductor light emitting device that emits red (R), green (G), and blue (B) light. In detail, the phosphor 2080 includes the quantum dot (QD) and the organic compound resin, and the bottom portion 2080 ′ is one surface of the second conductive semiconductor layer 2053 or the undoped semiconductor layer 2057 . may be formed on the Accordingly, the phosphor 2080 may be implemented integrally with the vertical semiconductor light emitting device 2050 .

Furthermore, after the phosphor 2080 is formed, a process of removing the photoresist may be performed. Accordingly, the undoped semiconductor layer 2057, the second conductivity type semiconductor layer 2053, the active layer 2054, and the first conductivity type semiconductor layer ( 2055), a first conductive electrode 2056, and a vertical semiconductor light emitting device 2050 in which a sacrificial layer (not shown) is formed may be formed.

Referring to FIG. 16B , the vertical semiconductor light emitting device 2050 bonded to the support substrate S may be supported in a fluid. In the vertical semiconductor light emitting device 2050 bonded to the supporting substrate S supported in the fluid, a sacrificial layer (not shown) between the supporting substrate S and the vertical semiconductor light emitting device 2050 is removed from the fluid. can be Accordingly, the vertical semiconductor light emitting device 2050 may be dispersed in the fluid.

Referring to FIG. 16C , the self-assembly method is a method in which the semiconductor light emitting devices are mounted on a wiring board or an assembly board in the chamber filled with the fluid. For example, the semiconductor light emitting devices and the substrate are put in a chamber filled with a fluid, and the fluid is heated so that the semiconductor light emitting devices are self-assembled on the substrate. To this end, the substrate may be provided with grooves into which the semiconductor light emitting devices are inserted. Specifically, grooves in which the semiconductor light emitting devices are seated are formed in the substrate at positions where the semiconductor light emitting devices are aligned with the wiring electrodes. The grooves have a shape corresponding to the shape of the semiconductor light emitting devices, and the semiconductor light emitting devices move randomly in the fluid and are assembled into the grooves.

Referring back to FIG. 16C , the substrate 2050 is immersed in a chamber filled with a fluid in order to couple the vertical semiconductor light emitting device 2050 to the substrate 2010 .

Since the vertical semiconductor light emitting device 2050 is contained in the chamber filled with the fluid, a step of mounting the semiconductor light emitting device 2050 on the substrate 2010 is performed.

For example, the vertical semiconductor light emitting devices 2050 and the substrate 2010 are put into a chamber filled with a fluid, and the fluid is heated so that the semiconductor light emitting devices are self-assembled on the substrate 2010 .

The substrate 2010 may be a glass or polymer substrate, or a flexible substrate. For example, in order to implement a flexible display device, the substrate 2010 may include glass or polyimide (PI). In addition, any material such as polyethylene naphthalate (PEN) or polyethylene terephthalate (PET) may be used as long as it has insulating properties and is flexible. Also, the substrate 2010 may be made of either a transparent material or an opaque material.

Referring to FIG. 16D , when the assembly of the vertical semiconductor light emitting device 2050 and the substrate 2010 is completed, the substrate 2010 may be taken out of the fluid to prepare for a subsequent process.

Meanwhile, the substrate 2010 may include a metal layer 2011 having high reflectivity. The metal layer 2011 may be made of high reflectivity silver (Ag), aluminum (Al), and APC (Ag+Pd+Cu) alloy, and may control optical characteristics of the vertical semiconductor light emitting device 2050 . The metal layer 2011 may serve to improve light efficiency by preventing light emitted from the vertical semiconductor light emitting device 2050 from being lost to the rear surface.

Referring to FIG. 16E , a filling layer 2030 for improving light extraction efficiency of a display device including the vertical semiconductor light emitting device 2050 may be filled between the vertical semiconductor light emitting devices 2050 . The electrolayer 2030 is formed up to the same plane as one surface of the second conductivity-type semiconductor layer 2053 , and the filling layer 2030 may be a white material and may be a material capable of improving light extraction efficiency.

Referring to FIG. 16F , a second conductive electrode 2052 may be formed. In detail, at least a portion of the undoped semiconductor layer 2057 may be etched through a known etching technique using a photoresist. Accordingly, the second conductivity type semiconductor layer 2053 is exposed, and the second conductivity type electrode 2052 may be formed in the region where the second conductivity type semiconductor layer 2053 is exposed. In an embodiment, the second conductive electrode 2052 may include a transparent electrode such as gold (Au), silver (Ag), nanowire, and indium tin oxide (ITO), the second conductive electrode (2052) is illustrative only, and the present invention is not limited thereto.

Referring back to FIG. 16F , the first conductivity type electrode 2056 and the second conductivity type electrode 2052 are disposed above and below, but at least a portion of the undoped semiconductor layer 2057 is etched into the etched area for second conductivity. Since the type electrode 2052 is formed, the light emitting surface of the vertical semiconductor light emitting device 2050 is covered by the electrode, so that the vertical semiconductor light emitting device 2050 can be formed without loss of an area through which light is output.

A phosphor 2080 including a quantum dot (QD) is integrated into the vertical semiconductor light emitting device 2050 so that the color of the semiconductor light emitting device can be freely realized, and red (R) and green (G) by the semiconductor light emitting device and a full-color display in which blue (B) unit pixels constitute one pixel may be implemented.

Referring to FIG. 16G , it may be difficult to obtain light of a desired color with light leaking through a region in which the undoped semiconductor layer 2057 is removed and an electrode is not formed. Accordingly, when unwanted light leakage occurs, a color filter 2073 capable of blocking the unwanted light may be further provided.

In addition, although not shown, a panel is disposed on one surface of the vertical semiconductor light emitting device on which the second conductive electrode 2052 is formed to protect the vertical semiconductor light emitting device. Since the panel is provided on the light emitting surface of the vertical semiconductor light emitting device, in order to minimize optical loss, the panel may be made of glass or a polymer material that allows light to pass through.

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

Claims (15)

A display device having a plurality of semiconductor light emitting devices, the display device comprising:
At least one of the semiconductor light emitting devices,
a first conductive semiconductor layer;
a second conductivity type semiconductor layer stacked on the first conductivity type semiconductor layer;
an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer; and
An undoped semiconductor layer formed on one surface of the second conductivity type semiconductor layer,
A display device, characterized in that at least a portion of the undoped semiconductor layer is formed with a groove recessed toward the second conductivity type semiconductor layer, and a phosphor is filled in the groove. According to claim 1,
The display device according to claim 1, wherein the phosphor has a bottom portion and a sidewall portion formed along an edge of the undoped semiconductor layer. 3. The method of claim 2,
The display device, characterized in that the bottom portion overlaps at least a portion of the second conductive type semiconductor layer. 3. The method of claim 2,
The display device, characterized in that the bottom portion is formed on the second conductive semiconductor layer. 3. The method of claim 2,
and the undoped semiconductor layer formed to cover the second conductivity type semiconductor layer between the bottom portion and the second conductivity type semiconductor layer. 3. The method of claim 2,
The display device, characterized in that at least a part of the sidewall portion is surrounded by the undoped semiconductor layer. 3. The method of claim 2,
The display device, characterized in that the side wall portion is formed to be inclined in a direction perpendicular to the bottom portion. 8. The method of claim 7,
The display device, characterized in that the cross-sectional area of the phosphor increases as the distance from the second conductive semiconductor layer increases due to the inclination of the sidewall portion. According to claim 1,
The display device, characterized in that the phosphor includes a quantum dot (QD). delete delete In the semiconductor light emitting device,
a first conductive semiconductor layer;
a second conductivity type semiconductor layer stacked on the first conductivity type semiconductor layer;
an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer; and
An undoped semiconductor layer formed on one surface of the second conductivity type semiconductor layer,
A semiconductor light emitting device, characterized in that at least a portion of the undoped semiconductor layer is formed with a groove recessed toward the second conductivity type semiconductor layer, and a phosphor is filled in the groove. delete delete delete

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