WO2023182625A1

WO2023182625A1 - Substrate for defect inspection, semiconductor light-emitting element and display device

Info

Publication number: WO2023182625A1
Application number: PCT/KR2022/095062
Authority: WO
Inventors: 강병준; 황성현; 박형조
Original assignee: 엘지전자 주식회사
Priority date: 2022-03-22
Filing date: 2022-03-22
Publication date: 2023-09-28

Abstract

The substrate for defect inspection comprises a transfer substrate and a plurality of semiconductor light-emitting elements spaced apart from each other on the substrate. Each of the plurality of semiconductor light-emitting elements includes: a light-emitting part; a first electrode including a plurality of first layers below the light-emitting part; a second electrode on the light-emitting part; and a passivation layer for encompassing the light-emitting part. At least one first layer from among the plurality of first layers of the first electrode is a common layer for commonly connecting each of the plurality of semiconductor light-emitting elements.

Description

Substrates for defect inspection, semiconductor light emitting devices and display devices

Examples relate to defect inspection substrates, semiconductor light-emitting devices, and display devices.

Large-area displays include liquid crystal displays (LCDs), OLED displays, and Micro-LED displays.

A micro-LED display is a display that uses micro-LED, a semiconductor light emitting device with a diameter or cross-sectional area of 100㎛ or less, as a display element.

Because micro-LED displays use micro-LED, a semiconductor light-emitting device, as a display device, they have excellent performance in many characteristics such as contrast ratio, response speed, color gamut, viewing angle, brightness, resolution, lifespan, luminous efficiency, and luminance.

In particular, the micro-LED display has the advantage of being able to freely adjust the size and resolution and implement a flexible display because the screen can be separated and combined in a modular manner.

However, because large micro-LED displays require more than millions of micro-LEDs, there is a technical problem that makes it difficult to quickly and accurately transfer micro-LEDs to the display panel.

Transfer technologies that have been recently developed include the pick and place process, laser lift-off method, or self-assembly method.

Among these, the self-assembly method is a method in which the semiconductor light-emitting device finds its assembly position within the fluid on its own, and is an advantageous method for implementing a large-screen display device.

Meanwhile, in a micro-LED display, each of tens of millions of micro-LEDs lights up (or emits light) to create an image. In particular, a lighting yield of 99.99999% (hereinafter referred to as target lighting yield) is required.

However, among tens of millions of micro-LEDs, there are quite a few micro-LEDs that do not light up due to defects due to various reasons. For example, micro-LEDs may have defects during the manufacturing process or transfer process, defects may occur during the self-assembly process, or defects may occur during post-processing after self-assembly.

In particular, even if lighting defects are reduced by improving the self-assembly process conditions or post-process conditions, if defects occurring during the manufacturing process or transfer process are not prevented in advance, the display panel manufactured by self-assembly may fall below the target lighting yield. Discarded due to defective display panel. It is very difficult for micro-LEDs with defects generated during the manufacturing process or transfer process to be restored to a lightable state through a repair process on the display panel.

Therefore, the electrical or optical properties of the micro-LED on which the manufacturing process or transfer process has been performed must be inspected.

The optical properties of micro-LEDs are inspected (or measured) using photoluminescence (PL) equipment. PL equipment does not require physical contact with the micro-LED, so it can easily measure the optical properties of the micro-LED.

The electrical properties of micro-LED are measured using EL (electroluminescence) equipment. In order to measure the electrical characteristics of a micro-LED, the probes of the EL equipment must be contacted to the corresponding electrodes of the micro-LED. In addition, because the probe is very sensitive to shaking, the micro-LED must be fixed to measure electrical characteristics. However, because micro-LEDs are very small in micrometer size, it is impossible to individually fix micro-LEDs. Therefore, during the transfer process of transferring the micro-LED, the electrical characteristics must be measured for the micro-LED fixed on the transfer substrate, but since one side of the micro-LED is not exposed by the transfer substrate, electrical contact by the probe is not possible. Therefore, there is a problem that the electrical characteristics of micro-LED cannot be measured.

Therefore, when a display device in which micro-LEDs are assembled through self-assembly is manufactured without measuring the electrical characteristics of the micro-LEDs, there is a problem in that it is difficult to obtain the target lighting yield. In addition, it is not possible to determine which process of the defective Micro-LED does not light up due to a defect occurring during the manufacturing process, transfer process, self-assembly process, or post-assembly process, so appropriate measures or improvement of the defect can be taken. There is a problem that is difficult to solve.

Therefore, there is an urgent need to develop technology to easily and in large quantities measure the electrical properties of micro-LEDs before self-assembly.

The embodiments aim to solve the above-described problems and other problems.

Another object of the embodiment is to provide a defect inspection substrate, a semiconductor light emitting device, and a display device having a new structure.

Additionally, another purpose of the embodiment is to provide a defect inspection substrate, a semiconductor light emitting device, and a display device that can improve lighting yield.

Additionally, another object of the embodiment is to provide a display device that can improve the assembly rate.

Additionally, another object of the embodiment is to provide a display device that facilitates electrical connection with a semiconductor light emitting device.

The technical problems of the embodiments are not limited to those described in this item and include those that can be understood through the description of the invention.

According to one aspect of the embodiment to achieve the above or other objects, a defect inspection substrate includes: a transfer substrate; and a plurality of semiconductor light emitting devices spaced apart from each other on the transfer substrate, wherein each of the plurality of semiconductor light emitting devices includes: a light emitting unit; a first electrode including a plurality of first layers below the light emitting unit; a second electrode on the light emitting unit; and a passivation layer surrounding the light emitting unit, wherein at least one first layer among the plurality of first layers of the first electrode is a common layer that commonly connects each of the plurality of semiconductor light emitting devices.

The common layer may have an area larger than the total area of the plurality of semiconductor light emitting devices.

The second electrode includes a plurality of second layers, and the uppermost layer of the plurality of second layers of the second electrode may be a conductive protective layer.

According to another aspect of the embodiment, a semiconductor light emitting device includes: a light emitting unit; a first electrode including a plurality of first layers below the light emitting unit; a second electrode on the light emitting unit; and a passivation layer surrounding the light emitting unit, wherein the first electrode may include a bonding layer having a diameter larger than the diameter of the light emitting unit.

The bonding layer includes: a first bonding layer below the light emitting unit; a second bonding layer below the first bonding layer; and a third bonding layer between the first bonding layer and the second bonding layer.

The second bonding layer may have a diameter larger than the diameter of the light emitting part.

The second bonding layer may include a protrusion that protrudes outward from a side of the light emitting unit.

The second bonding layer may have a diameter larger than that of at least one of the first bonding layer and the third bonding layer.

The second bonding layer may include a protrusion that protrudes outward from a side of at least one of the first bonding layer and the third bonding layer.

The third bonding layer may include the material of the first bonding layer and the material of the second bonding layer.

The first bonding layer and the second bonding layer may each include at least one of Sn, In, Cu, Au, Ag, Ni, Ti, W, Cr, or Pb, or an alloy thereof.

The first electrode may include at least one of an electrode layer, a magnetic layer, an ohmic layer, a reflective layer, an adhesive layer, and a barrier layer.

The first electrode may vertically overlap each of the light emitting unit and the passivation layer.

According to another aspect of the embodiment, a display device includes: a substrate including a plurality of sub-pixels; a plurality of first assembly wirings for each of the plurality of sub-pixels; a plurality of second assembly wirings for each of the plurality of sub-pixels; a partition wall having a plurality of assembly holes in each of the plurality of sub-pixels; a plurality of semiconductor light emitting devices in each of the plurality of assembly holes; and a plurality of connection electrodes, wherein each of the plurality of semiconductor light emitting devices includes: a light emitting unit; a first electrode including a plurality of first layers below the light emitting unit; a second electrode on the light emitting unit; and a passivation layer surrounding the light emitting unit, wherein the first electrode includes a bonding layer having a diameter larger than the diameter of the light emitting unit, and each of the connection electrodes includes the first electrode and the first assembled wiring. Alternatively, at least one assembly wiring among the second assembly wiring may be connected.

Each of the connection electrodes may be connected to the bonding layer.

The bonding layer includes: a first bonding layer below the light emitting unit; a second bonding layer below the first bonding layer; and a third bonding layer between the first bonding layer and the second bonding layer, wherein each of the connection electrodes may be connected to the side and top surfaces of the second bonding layer along the outer peripheral surface of the second bonding layer. there is.

Each of the connection electrodes may be connected to a side surface of each of the first bonding layer and the third bonding layer.

The first electrode includes at least one of an electrode layer, a magnetic layer, an ohmic layer, a reflective layer, an adhesive layer, and a barrier layer, and each of the connection electrodes may be connected to a side of the at least one layer.

The embodiment tracks semiconductor light-emitting devices with poor or defective electrical characteristics before self-assembly, separates defective semiconductor light-emitting devices from normal semiconductor light-emitting devices, and achieves the target lighting yield by assembling only normal semiconductor light-emitting devices on a display substrate. can do.

Specifically, as shown in FIGS. 7 and 8 , a plurality of semiconductor light emitting devices 150 may be electrically connected to the second bonding layer 132 disposed over the entire area of the transfer substrate 130. That is, the second bonding layer 132 may be a common layer that commonly connects the plurality of semiconductor light emitting devices 150. Therefore, as shown in FIG. 9, the first probe 1021 of the PL inspection equipment 1020 contacts one point of the second bonding layer 132, and a plurality of

second probes

1022 and 1023 are connected to each other. After contacting the second electrode 155 of the semiconductor light emitting device 150, voltage is supplied through the first probe 1021 and the

second probes

1022 and 1023 to each of the plurality of semiconductor light emitting devices 150. Electrical properties can be tested.

Therefore, in the embodiment, the electrical characteristics of each of the plurality of semiconductor light-emitting devices 150 are simultaneously performed at once using the second bonding layer 132 commonly connected to each of the plurality of semiconductor light-emitting devices 150, thereby improving productivity. It can be improved dramatically.

Meanwhile, as a result of the inspection of electrical characteristics, the semiconductor light emitting device determined to be defective is decomposed into fragments or particles using a destruction equipment 1030, and the decomposed fragments or particles are collected and removed, as shown in FIG. 10. It can be. Thereafter, the transfer substrate 130 is removed, so that only a plurality of normal semiconductor light emitting devices 150 can be manufactured. By mounting these normal semiconductor light emitting devices 150 on the display panel through a self-assembly process and post-processing, the lighting yield can be improved.

Meanwhile, as shown in FIG. 12, the second bonding layer 132 used to inspect electrical characteristics may be formed as a part of the first electrode 154 of the semiconductor light emitting device 150. At this time, the second bonding layer 132 may include a protrusion 132a that protrudes outward from the side of the light emitting unit 150a.

As shown in FIG. 14, the semiconductor light emitting device 150-1 may be assembled on the substrate 310 and the connection electrode 370 may be disposed in the assembly hole 340H. In this case, by expanding the size of the second bonding layer 132, the connection area with the connection electrode 370 increases, thereby further increasing luminance and the contact area with the connection electrode 370 increases, thereby forming a semiconductor light emitting device ( The fixity of 150-1) can be further strengthened.

Meanwhile, as shown in FIG. 15, the first electrode 154 of the semiconductor light emitting device 150A may include a transparent electrode layer 155-1 and a conductive protective layer 155-2. As shown in FIG. 16, when inspecting electrical characteristics using the PL inspection equipment 1020, the

second probes

1022 and 1023 contact the conductive protective layer 155-2, so the second probe 1022 , 1023), the transparent electrode layer 155-1 can be protected from pressure applied to the electrode layer 155-1. Accordingly, the transparent electrode layer 155-1 is not scratched or damaged by the

second probes

1022 and 1023, thereby preventing deterioration in electrical or optical properties.

Additional scope of applicability of the embodiments will become apparent from the detailed description that follows. However, since various changes and modifications within the spirit and scope of the embodiments may be clearly understood by those skilled in the art, the detailed description and specific embodiments, such as preferred embodiments, should be understood as being given by way of example only.

Figure 1 shows a living room of a house where a display device according to an embodiment is installed.

Figure 2 is a block diagram schematically showing a display device according to an embodiment.

FIG. 3 is a circuit diagram showing an example of the pixel of FIG. 2.

FIG. 4 is an enlarged view of the first panel area in the display device of FIG. 1.

Figure 5 is an enlarged view of area A2 in Figure 4.

Figure 6 is a diagram showing an example in which a light emitting device according to an embodiment is assembled on a substrate by a self-assembly method.

Figure 7 is a cross-sectional view showing a defect inspection substrate according to the first embodiment.

Figure 8 is a plan view showing a defect inspection substrate according to the first embodiment.

FIG. 9 shows inspecting the electrical characteristics of a defect inspection board according to the first embodiment.

FIG. 10 shows removal of a semiconductor light emitting device determined to be defective in the electrical characteristics test results in FIG. 8 .

11A to 11M are diagrams illustrating a manufacturing process for a semiconductor light emitting device according to an embodiment.

Figure 12 is a cross-sectional view showing a semiconductor light emitting device according to the first embodiment.

Figure 13 is a plan view showing a display device including a semiconductor light emitting device according to the first embodiment.

FIG. 14 is a cross-sectional view taken along line C1-C2 of the first sub-pixel in the display device according to the embodiment of FIG. 12.

Figure 15 is a cross-sectional view showing a defect inspection substrate according to a second embodiment.

FIG. 16 shows inspecting the electrical characteristics of a defect inspection board according to the second embodiment.

Figure 17 is a cross-sectional view showing a semiconductor light-emitting device according to the second embodiment.

Figure 18 is a cross-sectional view showing a display device including a semiconductor light-emitting device according to a second embodiment.

The size, shape, and dimensions of components shown in the drawings may differ from actual ones. In addition, although the same components are shown in different sizes, shapes, and numbers between the drawings, this is only an example in the drawings, and the same components are shown in the same size, shape, and number across the drawings. You can have it.

Hereinafter, embodiments disclosed in the present specification will be described in detail with reference to the attached drawings. However, identical or similar components will be assigned the same reference numbers regardless of reference numerals, and duplicate descriptions thereof will be omitted. The suffixes 'module' and 'part' for components used in the following description are given or used interchangeably in consideration of ease of specification preparation, and do not have distinct meanings or roles in themselves. Additionally, the attached drawings are intended to facilitate easy understanding of the embodiments disclosed in this specification, and the technical idea disclosed in this specification is not limited by the attached drawings. Additionally, when an element such as a layer, region or substrate is referred to as being 'on' another component, this includes either directly on the other element or there may be other intermediate elements in between. do.

Display devices described in this specification include TVs, shines, mobile phones, smart phones, head-up displays (HUDs) for automobiles, backlight units for laptop computers, displays for VR or AR, etc. You can. However, the configuration according to the embodiment described in this specification can be applied to a device capable of displaying even if it is a new product type that is developed in the future.

Hereinafter, a light emitting device according to an embodiment and a display device including the same will be described.

Referring to FIG. 1, the display device 100 of the embodiment can display the status of various electronic products such as a washing machine 101, a robot vacuum cleaner 102, and an air purifier 103, and displays the status of each electronic product and an IOT-based You can communicate with each other and control each electronic product based on the user's setting data.

The display device 100 according to an embodiment may include a flexible display manufactured on a thin and flexible substrate. Flexible displays can bend or curl like paper while maintaining the characteristics of existing flat displays.

In a flexible display, visual information can be implemented by independently controlling the light emission of unit pixels arranged in a matrix form. A unit pixel refers to the minimum unit for implementing one color. A unit pixel of a flexible display may be implemented by a light-emitting device. In the embodiment, the light emitting device may be Micro-LED or Nano-LED, but is not limited thereto.

FIG. 2 is a block diagram schematically showing a display device according to an embodiment, and FIG. 3 is a circuit diagram showing an example of the pixel of FIG. 2.

Referring to FIGS. 2 and 3 , a display device according to an embodiment may include a display panel 10, a driving circuit 20, a scan driver 30, and a power supply circuit 50.

The display device 100 of the embodiment may drive the light emitting device in an active matrix (AM) method or a passive matrix (PM) method.

The driving circuit 20 may include a data driver 21 and a timing control unit 22.

The display panel 10 may be rectangular, but is not limited thereto. That is, the display panel 10 may be formed in a circular or oval shape. At least one side of the display panel 10 may be bent to a predetermined curvature.

The display panel 10 may be divided into a display area (DA) and a non-display area (NDA) disposed around the display area (DA). The display area DA is an area where pixels PX are formed to display an image. The display panel 10 includes data lines (D1 to Dm, m is an integer greater than 2), scan lines (S1 to Sn, n is an integer greater than 2) that intersect the data lines (D1 to Dm), and a high potential voltage. The pixels (PX) connected to the high-potential voltage line (VDDL) supplied, the low-potential voltage line (VSSL) supplied with the low-potential voltage, and the data lines (D1 to Dm) and scan lines (S1 to Sn). It can be included.

Each of the pixels PX may include a first sub-pixel PX1, a second sub-pixel PX2, and a third sub-pixel PX3. The first sub-pixel (PX1) emits a first color light of a first main wavelength, the second sub-pixel (PX2) emits a second color light of a second main wavelength, and the third sub-pixel (PX3) A third color light of a third main wavelength may be emitted. The first color light may be red light, the second color light may be green light, and the third color light may be blue light, but are not limited thereto. Additionally, in FIG. 2, it is illustrated that each of the pixels PX includes three sub-pixels, but the present invention is not limited thereto. That is, each pixel PX may include four or more sub-pixels.

Each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) includes at least one of the data lines (D1 to Dm), at least one of the scan lines (S1 to Sn), and It can be connected to the above voltage line (VDDL). As shown in FIG. 3 , the first sub-pixel PX1 may include light-emitting devices LD, a plurality of transistors for supplying current to the light-emitting devices LD, and at least one capacitor Cst.

Although not shown in the drawing, each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) may include only one light emitting element (LD) and at least one capacitor (Cst). It may be possible.

Each of the light emitting elements LD may be a semiconductor light emitting diode including a first electrode, a plurality of conductive semiconductor layers, and a second electrode. Here, the first electrode may be an anode electrode and the second electrode may be a cathode electrode, but this is not limited.

The light emitting device (LD) may be one of a horizontal light emitting device, a flip chip type light emitting device, and a vertical light emitting device.

As shown in FIG. 3 , the plurality of transistors may include a driving transistor (DT) that supplies current to the light emitting elements (LD) and a scan transistor (ST) that supplies a data voltage to the gate electrode of the driving transistor (DT). The driving transistor DT is connected to a gate electrode connected to the source electrode of the scan transistor ST, a source electrode connected to the high potential voltage line VDDL to which a high potential voltage is applied, and the first electrodes of the light emitting elements LD. It may include a connected drain electrode. The scan transistor (ST) has a gate electrode connected to the scan line (Sk, k is an integer satisfying 1≤k≤n), a source electrode connected to the gate electrode of the driving transistor (DT), and a data line (Dj, j). It may include a drain electrode connected to an integer satisfying 1≤j≤m.

The capacitor Cst is formed between the gate electrode and the source electrode of the driving transistor DT. The storage capacitor (Cst) charges the difference between the gate voltage and source voltage of the driving transistor (DT).

The driving transistor (DT) and the scan transistor (ST) may be formed of a thin film transistor. In addition, in FIG. 3, the driving transistor (DT) and the scan transistor (ST) are mainly described as being formed of a P-type MOSFET (Metal Oxide Semiconductor Field Effect Transistor), but the present invention is not limited thereto. The driving transistor (DT) and scan transistor (ST) may be formed of an N-type MOSFET. In this case, the positions of the source and drain electrodes of the driving transistor (DT) and the scan transistor (ST) may be changed.

In addition, in FIG. 3, each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) includes one driving transistor (DT), one scan transistor (ST), and one capacitor ( Although it is exemplified to include 2T1C (2 Transistor - 1 capacitor) with Cst), the present invention is not limited thereto. Each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) may include a plurality of scan transistors (ST) and a plurality of capacitors (Cst).

Since the second sub-pixel (PX2) and the third sub-pixel (PX3) can be represented by substantially the same circuit diagram as the first sub-pixel (PX1), detailed descriptions thereof will be omitted.

The driving circuit 20 outputs signals and voltages for driving the display panel 10. For this purpose, the driving circuit 20 may include a data driver 21 and a timing controller 22.

The data driver 21 receives digital video data (DATA) and source control signal (DCS) from the timing control unit 22. The data driver 21 converts digital video data (DATA) into analog data voltages according to the source control signal (DCS) and supplies them to the data lines (D1 to Dm) of the display panel 10.

The timing control unit 22 receives digital video data (DATA) and timing signals from the host system. Timing signals may include a vertical sync signal, a horizontal sync signal, a data enable signal, and a dot clock. The host system may be an application processor in a smartphone or tablet PC, a monitor, or a system-on-chip in a TV.

The timing control unit 22 generates control signals to control the operation timing of the data driver 21 and the scan driver 30. The control signals may include a source control signal (DCS) for controlling the operation timing of the data driver 21 and a scan control signal (SCS) for controlling the operation timing of the scan driver 30.

The driving circuit 20 may be disposed in the non-display area (NDA) provided on one side of the display panel 10. The driving circuit 20 may be formed of an integrated circuit (IC) and mounted on the display panel 10 using a chip on glass (COG) method, a chip on plastic (COP) method, or an ultrasonic bonding method. The present invention is not limited to this. For example, the driving circuit 20 may be mounted on a circuit board (not shown) rather than on the display panel 10.

The data driver 21 may be mounted on the display panel 10 using a chip on glass (COG) method, a chip on plastic (COP) method, or an ultrasonic bonding method, and the timing control unit 22 may be mounted on a circuit board. there is.

The scan driver 30 receives a scan control signal (SCS) from the timing controller 22. The scan driver 30 generates scan signals according to the scan control signal SCS and supplies them to the scan lines S1 to Sn of the display panel 10. The scan driver 30 may include a plurality of transistors and may be formed in the non-display area NDA of the display panel 10. Alternatively, the scan driver 30 may be formed as an integrated circuit, and in this case, it may be mounted on a gate flexible film attached to the other side of the display panel 10.

The circuit board may be attached to pads provided at one edge of the display panel 10 using an anisotropic conductive film. Because of this, the lead lines of the circuit board can be electrically connected to the pads. The circuit board may be a flexible printed circuit board, a printed circuit board, or a flexible film such as a chip on film. The circuit board may be bent toward the bottom of the display panel 10. Because of this, one side of the circuit board is attached to one edge of the display panel 10, and the other side is placed below the display panel 10 and can be connected to a system board on which the host system is mounted.

The power supply circuit 50 may generate voltages necessary for driving the display panel 10 from the main power supplied from the system board and supply them to the display panel 10. For example, the power supply circuit 50 generates a high potential voltage (VDD) and a low potential voltage (VSS) for driving the light emitting elements (LD) of the display panel 10 from the main power supply to It can be supplied to the high potential voltage line (VDDL) and low potential voltage line (VSSL). Additionally, the power supply circuit 50 may generate and supply driving voltages for driving the driving circuit 20 and the scan driver 30 from the main power supply.

FIG. 4 is an enlarged view of the first panel area in the display device of FIG. 3.

Referring to FIG. 4 , the display device 100 of the embodiment may be manufactured by mechanically and electrically connecting a plurality of panel areas, such as the first panel area A1, by tiling.

The first panel area A1 may include a plurality of semiconductor light emitting devices 150 arranged for each unit pixel (PX in FIG. 2).

For example, the unit pixel PX may include a first sub-pixel PX1, a second sub-pixel PX2, and a third sub-pixel PX3. For example, a plurality of red semiconductor light-emitting devices 150R are disposed in the first sub-pixel PX1, a plurality of green semiconductor light-emitting devices 150G are disposed in the second sub-pixel PX2, and a plurality of blue semiconductor light-emitting devices are disposed in the second sub-pixel PX2. (150B) may be disposed in the third sub-pixel (PX3). The unit pixel PX may further include a fourth sub-pixel in which a semiconductor light-emitting device is not disposed, but this is not limited.

Figure 5 is an enlarged view of area A2 in Figure 4.

Referring to FIG. 5 , the display device 100 of the embodiment may include a substrate 200, assembly wiring 201 and 202, an insulating layer 206, and a plurality of semiconductor light emitting devices 150. More components may be included than this.

The assembly wiring may include a first assembly wiring 201 and a second assembly wiring 202 that are spaced apart from each other. The first assembly wiring 201 and the second assembly wiring 202 may be provided to generate dielectrophoresis force (DEP force) to assemble the semiconductor light emitting device 150. For example, the semiconductor light emitting device 150 may be one of a horizontal semiconductor light emitting device, a flip chip type semiconductor light emitting device, and a vertical semiconductor light emitting device.

The semiconductor light-emitting device 150 may include, but is not limited to, a red semiconductor light-emitting device 150, a green semiconductor light-emitting device 150G, and a blue semiconductor light-emitting device 150B0 to form a unit pixel (sub-pixel). , red and green phosphors may be provided to implement red and green colors, respectively.

The substrate 200 may be a support member that supports components disposed on the substrate 200 or a protection member that protects the components.

The substrate 200 may be a rigid substrate or a flexible substrate. The substrate 200 may be made of sapphire, glass, silicon, or polyimide. Additionally, the substrate 200 may include a flexible material such as PEN (Polyethylene Naphthalate) or PET (Polyethylene Terephthalate). Additionally, the substrate 200 may be made of a transparent material, but is not limited thereto. The substrate 200 may function as a support substrate in a display panel, and may also function as an assembly substrate when self-assembling a light emitting device.

The substrate 200 may be a backplane equipped with circuits in the sub-pixels (PX1, PX2, PX3) shown in FIGS. 2 and 3, such as transistors (ST, DT), capacitors (Cst), signal wires, etc. However, there is no limitation to this.

The insulating layer 206 may include an insulating and flexible organic material such as polyimide, PAC, PEN, PET, polymer, etc., or an inorganic material such as silicon oxide (SiO2) or silicon nitride series (SiNx), and may include a substrate. (200) may be integrated to form one substrate.

The insulating layer 206 may be a conductive adhesive layer that has adhesiveness and conductivity, and the conductive adhesive layer may be flexible and enable a flexible function of the display device. For example, the insulating layer 206 may be an anisotropic conductive film (ACF) or a conductive adhesive layer such as an anisotropic conductive medium or a solution containing conductive particles. The conductive adhesive layer may be a layer that is electrically conductive in a direction perpendicular to the thickness, but electrically insulating in a direction horizontal to the thickness.

The insulating layer 206 may include an assembly hole 203 into which the semiconductor light emitting device 150 is inserted. Therefore, during self-assembly, the semiconductor light emitting device 150 can be easily inserted into the assembly hole 203 of the insulating layer 206. The assembly hole 203 may be called an insertion hole, a fixing hole, an alignment hole, etc. The assembly hall 203 may also be called a hall.

The assembly hole 203 may be called a hole, groove, groove, recess, pocket, etc.

The assembly hole 203 may be different depending on the shape of the semiconductor light emitting device 150. For example, the red semiconductor light emitting device, the green semiconductor light emitting device, and the blue semiconductor light emitting device each have different shapes, and may have an assembly hole 203 having a shape corresponding to the shape of each of these semiconductor light emitting devices. For example, the assembly hole 203 may include a first assembly hole for assembling a red semiconductor light emitting device, a second assembly hole for assembling a green semiconductor light emitting device, and a third assembly hole for assembling a blue semiconductor light emitting device. there is. For example, the red semiconductor light emitting device has a circular shape, the green semiconductor light emitting device has a first oval shape with a first minor axis and a second major axis, and the blue semiconductor light emitting device has a second oval shape with a second minor axis and a second major axis. However, there is no limitation to this. The second major axis of the oval shape of the blue semiconductor light emitting device may be greater than the second major axis of the oval shape of the green semiconductor light emitting device, and the second minor axis of the oval shape of the blue semiconductor light emitting device may be smaller than the first minor axis of the oval shape of the green semiconductor light emitting device.

Meanwhile, methods for mounting the semiconductor light emitting device 150 on the substrate 200 may include, for example, a self-assembly method (FIG. 6) and a transfer method.

Based on FIG. 6, an example in which a semiconductor light emitting device according to an embodiment is assembled into a display panel by a self-assembly method using an electromagnetic field will be described.

The assembled substrate 200, which will be described later, can also function as the panel substrate 200a in a display device after assembly of the light emitting device, but the embodiment is not limited thereto.

Referring to FIG. 6, the semiconductor light emitting device 150 may be introduced into the chamber 1300 filled with the fluid 1200, and the semiconductor light emitting device 150 may be placed on the assembly substrate ( 200). At this time, the light emitting device 150 adjacent to the assembly hole 207H of the assembly substrate 200 may be assembled into the assembly hole 207H by DEP force caused by the electric field of the assembly wiring. The fluid 1200 may be water such as ultrapure water, but is not limited thereto. The chamber may be called a water tank, container, vessel, etc.

After the semiconductor light emitting device 150 is input into the chamber 1300, the assembled substrate 200 may be placed on the chamber 1300. Depending on the embodiment, the assembled substrate 200 may be input into the chamber 1300.

After the assembled substrate 200 is placed in the chamber, the assembled device 1100 that applies a magnetic field may move along the assembled substrate 200. Assembly device 1100 may be a permanent magnet or an electromagnet.

The assembly device 1100 may move while in contact with the assembly substrate 200 in order to maximize the area to which the magnetic field is applied within the fluid 1200. Depending on the embodiment, the assembly device 1100 may include a plurality of magnetic materials or may include a magnetic material of a size corresponding to that of the assembly substrate 200. In this case, the moving distance of the assembly device 1100 may be limited to within a predetermined range.

The semiconductor light emitting device 150 in the chamber 1300 may move toward the assembly device 1100 and the assembly substrate 200 by the magnetic field generated by the assembly device 1100.

Hereinafter, various embodiments for solving the above-described problem will be described with reference to FIGS. 7 to 18. Descriptions omitted below can be easily understood from FIGS. 1 to 6 and the description given above in relation to the corresponding drawings.

[First Example]

Figure 7 is a cross-sectional view showing a defect inspection substrate according to the first embodiment. Figure 8 is a plan view showing a defect inspection substrate according to the first embodiment.

Referring to FIGS. 7 and 8 , the defect inspection substrate 1000 according to the first embodiment may include a transfer substrate 130 and a plurality of semiconductor light emitting devices 150.

The transfer substrate 130 may be a temporary substrate. The transfer substrate 130 may serve to temporarily support the plurality of semiconductor light emitting devices 150 to inspect the electrical characteristics of each of the plurality of semiconductor light emitting devices 150 disposed thereon. To this end, a plurality of semiconductor light-emitting devices 150 are bonded to the transfer substrate 130 through

bonding layers

112, 132, and 133. The bonding layers 112, 132, and 133 are connected to a plurality of semiconductor light-emitting devices 150. It may be composed of a portion of each first electrode 154. This will be explained in detail later.

In more detail, as shown in FIG. 11A, a plurality of light emitting units 150a may be formed on the growth substrate 110. Each of the plurality of light emitting units 150a may be obtained by sequentially depositing a plurality of semiconductor layers on the growth substrate 110 and then performing mesa etching. The plurality of semiconductor layers constitute the light emitting unit 150a and may include, for example, at least one first conductivity type semiconductor layer, an active layer, and at least one second conductivity type semiconductor layer. For example, the first conductivity type semiconductor layer may include a first dopant, such as Si, and the second conductivity type semiconductor layer may include a second dopant, such as Mn.

Afterwards, the second electrode 155 may be formed on the light emitting part 150a and the passivation layer 157 may be formed to surround the light emitting part 150a. The second electrode 155 may include a transparent electrode layer 155-1. That is, the light generated in the light emitting unit 150a may pass through the second electrode 155 and be emitted forward. Accordingly, the second electrode 155 may include a material with excellent transmittance, such as ITO. A portion of the passivation layer 157 corresponding to the second electrode 155 may be removed to form an opening 158 . Later, when the electrical properties of the semiconductor light emitting device 150 are inspected, each of the

second probes

1022 and 1023 of the PL inspection equipment (1020 in FIG. 9) will be contacted with the second electrode 155 through the opening 158. You can.

Afterwards, the first electrode 154 may be formed below the light emitting unit 150a.

The defect inspection substrate 1000 shown in FIGS. 7 and 8 is a substrate for forming the first electrode 154 below the light emitting unit 150a and simultaneously inspects the electrical characteristics of a plurality of semiconductor light emitting devices 150. It may be a substrate that can do this. In other words, the defect inspection substrate 1000 of the embodiment can be used to simultaneously inspect the electrical characteristics of a plurality of semiconductor light-emitting devices 150 to determine which semiconductor light-emitting devices 150 have defective electrical characteristics. In addition, the inspection electrode used to simultaneously inspect the electrical characteristics of a plurality of semiconductor light-emitting devices 150, that is, the second bonding layer 132, forms part of the second electrode 155 of the semiconductor light-emitting device 150. , It can be used to facilitate electrical connection of the lower part of the semiconductor light emitting device 150 when manufacturing a display panel.

Referring again to FIG. 7, a semiconductor including a conductive layer 111, a first bonding layer 112, a light emitting portion 150a, a second electrode 155, and a passivation layer 157 is formed through a wafer process and a transfer process. Light emitting device 150 can be manufactured.

The conductive layer 111 may include multiple layers. For example, the conductive layer 111 may include at least one of an electrode layer, a magnetic layer, an ohmic layer, a reflective layer, an adhesive layer, and a barrier layer. The electrode layer improves current flow with the light emitting unit 150a and may include a material with excellent electrical conductivity, such as Cu. The magnetic layer is magnetized by the assembly device (1100 in FIG. 6) during self-assembly, and the semiconductor light emitting device 150 moves faster and more quickly as the assembly device 1100 moves, shortening the process time and improving assembly yield. You can do it. For example, the magnetic layer may include nickel (Ni), cobalt (Co), iron (Fe), etc. The ohmic layer may serve to lower the contact resistance with the light emitting unit 150a. The reflective layer can improve light efficiency by reflecting light generated in the light emitting unit 150a forward. The reflective layer may include a material with excellent reflectivity, such as Al.

A sacrificial layer 131 and a second bonding layer 132 may be disposed on the transfer substrate 130. The sacrificial layer 131 is removed through an etching process, and the transfer substrate 130 and the second bonding layer 132 may be separated due to the removal of the sacrificial layer 131.

As shown in FIG. 8, the second bonding layer 132 is disposed on the entire area of the transfer substrate 130, and each of the plurality of semiconductor light emitting devices 150 disposed on the second bonding layer 132 It may be a common electrode to simultaneously perform the electrical characteristics of. For example, the second bonding layer 132 may be larger than the total area of the plurality of semiconductor light emitting devices 150. Since the plurality of semiconductor light-emitting devices 150 are spaced apart from each other, the second bonding layer 132 between the plurality of semiconductor light-emitting devices 150 may be exposed to the outside. The second bonding layer 132 corresponding to the edge of the transfer substrate 130 may be exposed to the outside. Accordingly, when inspecting the electrical characteristics of each of the plurality of semiconductor light emitting devices 150, a probe (1021 in FIG. 9) may be contacted at one point of the exposed second bonding layer 132.

Conventionally, the second electrode 155 is formed under the plurality of semiconductor light-emitting devices 150 using a stuttering process, so that the plurality of semiconductor light-emitting devices 150 are independently separated. ) Electrical properties were tested through contact of a probe to each of the first electrode 154 and the second electrode 155. However, since the semiconductor light emitting device 150 has a size of less than a micrometer, it is impossible to independently inspect the electrical characteristics of tens of millions of semiconductor light emitting devices 150 provided in one display panel. Even if the electrical characteristics of the semiconductor light emitting device 150 are independently inspected, there is a problem that productivity is reduced because the inspection time takes too long.

However, according to the embodiment, a second bonding layer 132 having the same or similar size as the transfer substrate 130 is previously provided on the transfer substrate 130, and the first bonding layer of the plurality of semiconductor light emitting devices 150 is formed. The layer 112 and the second bonding layer 132 on the transfer substrate 130 are bonded by eutectic bonding, so that the second electrode 155 of each of the plurality of semiconductor light-emitting devices 150 and the plurality of semiconductor light-emitting devices 150 The electrical characteristics of each of the plurality of semiconductor light emitting devices 150 can be performed simultaneously through the second bonding layer 132 commonly connected to the , thereby dramatically increasing productivity.

In addition, by determining the semiconductor light emitting device 150 with defective electrical characteristics before self-assembly and removing the semiconductor light emitting device 150, the display panel manufactured through the self-assembly process and post-process is prevented from being discarded as defective. Costs can be dramatically reduced and target lighting yields can be achieved.

Meanwhile, the plurality of semiconductor light emitting devices 150 and the transfer substrate 130 may be bonded using eutectic bonding. Eutectic bonding can be a technology that joins different metals at a low temperature by applying heat and pressure.

For example, each of the first bonding layer 112 and the second bonding layer 132 may include at least one of Sn, In, Cu, Au, Ag, Ni, Ti, W, Cr, or Pb, or an alloy thereof. . For example, the first bonding layer 112/second bonding layer 132 includes Sn/Au, Sn/Cu, Sn/Pb, and Au/Si.

Accordingly, the first bonding layer 112 and the second bonding layer 132 may be selected from Sn, Au, Cu, Pb, Si, etc. For example, when the first bonding layer 112 is Sn, the second bonding layer 132 can be Au, Cu, Pb, Si, etc.

Specifically, a plurality of semiconductor light emitting devices 150 may be positioned on the transfer substrate 130 while maintaining a preset interval. At this time, the first bonding layer 112 of each of the plurality of semiconductor light emitting devices 150 may be in contact with the second bonding layer 132 on the transfer substrate 130. Thereafter, heat and pressure are applied through eutectic bonding, thereby forming a third bonding layer 133 between the first bonding layer 112 and the second bonding layer 132, and this third bonding layer 133 is By doing this, a plurality of semiconductor light emitting devices 150 can be bonded to the transfer substrate 130.

The third bonding layer 133 includes an inter-metallic compound and, for example, may include the material of the first bonding layer 112 and the material of the second bonding layer 132. For example, the third bonding layer 133 may be a compound of Sn and Au, a compound of Sn and Cu, a compound of Sn and Pb, a compound of Au and Si, etc.

Since the third bonding layer 133 contains the material of the first bonding layer 112 constituting the semiconductor light emitting device 150, it may have the same size as the first bonding layer 112, but this is limited. I never do that.

A plurality of semiconductor light emitting devices 150 can be bonded to the transfer substrate 130 at a relatively low temperature, for example, 200° C. or lower, using eutectic bonding technology.

Typically, when the semiconductor light emitting device 150 and the transfer substrate 130 are bonded at 500°C or higher through high temperature thermal bonding technology, the electrical characteristics or optical properties of the light emitting unit 150a constituting the semiconductor light emitting device 150 are affected due to the high temperature. Characteristics may deteriorate, the second electrode 155 or the passivation layer 157 may melt, or thermal deformation may occur.

However, in the embodiment, the semiconductor light emitting device 150 and the electronic substrate are bonded at low temperature using eutectic bonding technology, so the above-described problem can be solved.

Although two semiconductor light-emitting devices 150 are shown in FIG. 7 for convenience, as shown in FIG. 8, a plurality of semiconductor light-emitting devices 150 are attached to the transfer substrate 130 through a eutectic bong. can be joined.

As an example, the plurality of semiconductor light emitting devices 150 bonded on the transfer substrate 130 may be semiconductor light emitting devices 150 that generate light of the same color.

As another example, the plurality of semiconductor light emitting devices 150 bonded on the transfer substrate 130 may be semiconductor light emitting devices 150 that generate light of different colors. For example, the plurality of semiconductor light-emitting devices 150 include the first semiconductor light-emitting device 150-1, the second semiconductor light-emitting device 150-2, and the third semiconductor light-emitting device 150-3 shown in FIG. 13. can do. For example, the first semiconductor light emitting device 150-1 generates a first color light, such as red light, the second semiconductor light emitting device 150-2 generates a second color light, such as green light, and the third The semiconductor light emitting device 150-3 may generate third color light, for example, blue light.

Therefore, according to the embodiment, the electrical characteristics of each of the plurality of semiconductor light-emitting devices 150 that generate the same color light or the plurality of semiconductor light-emitting devices 150 that generate different color lights can be inspected at the same time. , productivity can be dramatically improved.

In FIG. 13, the first semiconductor light-emitting device 150-1, the second semiconductor light-emitting device 150-2, and the third semiconductor light-emitting device 150-3 are all shown as having the same shape, that is, a circular shape, but have different shapes. It may have a shape. For example, the first semiconductor light emitting device 150-1 has a circular shape, the second semiconductor light emitting device 150-2 has a first oval shape with a first long axis, and the third semiconductor light emitting device 150-3 has a first oval shape. It may have a second oval shape with a second major axis that is greater than the first major axis.

Meanwhile, the transfer substrate 130 shown in FIG. 7 may be larger than the growth substrate 110 on which the semiconductor light emitting device 150 is manufactured. For example, the transfer substrate 130 may have the same size as the display panel on which tens of millions of semiconductor light emitting devices 150 are provided. In this case, after tens of millions of semiconductor light emitting devices 150 are bonded on the transfer substrate 130, the electrical characteristics of each of the tens of millions of semiconductor light emitting devices 150 can be inspected simultaneously through a single inspection process. You can.

As shown in FIG. 9, the electrical characteristics of each of the plurality of semiconductor light emitting devices 150 can be inspected using the PL inspection equipment 1020.

That is, the defective inspection substrate shown in FIG. 8 may be moved or the PL inspection equipment 1020 may be moved. Subsequently, the

probes

1021, 1022, and 1023 provided in the PL inspection equipment 1020 may be contacted at a preset location. For example, the first probe 1021 contacts the second bonding layer 132 disposed on the transfer substrate 130, and the

second probes

1022 and 1023 contact each of the plurality of semiconductor light emitting devices 150. 2 may be contacted with the electrode 155. For example, the

second probes

1022 and 1023 may be comprised of a plurality.

The first probe 1021 may contact a point of the second bonding layer 132 located at the edge of the transfer substrate 130, but this is not limited.

As an example, when I-V characteristics are tested as electrical characteristics, a low level or negative (-) voltage is supplied to the first probe 1021, and a high level or positive (+) voltage is supplied to the second probe 1022, 1023).

As another example, when the reverse current characteristic as an electrical characteristic is tested, a high level or positive (+) voltage is supplied to the first probe 1021, and a low level or negative (-) voltage is supplied to the first probe 1021. It can be supplied as 2 probes (1022, 1023).

When power is supplied through the first probe 1021 and the

second probes

1022 and 1023 to test electrical characteristics, a detection sensor (not shown) for detecting the corresponding electrical characteristics is connected to the first probe 1021 or the second probe 1021. It may be provided on two

probes

1022 and 1023. I-V characteristics or reverse current characteristics are obtained through a detection sensor, and based on the obtained results, it can be determined whether the electrical characteristics of each of the plurality of semiconductor light emitting devices 150 are defective.

After the plurality of semiconductor light emitting devices 150 are separated from the transfer substrate 130, it is not possible to distinguish between normal semiconductor light emitting devices and defective semiconductor light emitting devices. Therefore, before the plurality of semiconductor light emitting devices 150 are separated from the transfer substrate 130, only the corresponding defective semiconductor light emitting devices must be removed.

For this purpose, destruction equipment 1030 may be used, as shown in FIG. 10 .

In an embodiment, the destruction equipment 1030 may supply high voltage through the first probe 1031 and the second probe 1032. For example, the high voltage supplied from the destruction equipment 1030 may supply a voltage greater than the rated voltage of each semiconductor light emitting device 150. The high voltage may be a voltage that can physically destroy the semiconductor light emitting device 150 and disintegrate it into fragments or particles.

A defective semiconductor light emitting device 150 can be determined through electrical characteristic inspection using the PL inspection equipment 1020 shown in FIG. 9 . At this time, the location of a defective semiconductor light emitting device on the transfer substrate 130 may be identified. For example, when a plurality of semiconductor light emitting devices 150 are positioned on the transfer substrate 130 to be bonded to the transfer substrate 130, the positions of each of the plurality of semiconductor light emitting devices 150 may be systematically recorded. . Afterwards, when the electrical characteristics of each of the plurality of semiconductor light-emitting devices 150 are inspected using the PL inspection equipment 1020, normal or defective information is generated in correspondence with the pre-recorded position information of each of the plurality of semiconductor light-emitting devices 150. can be recorded.

Based on this information, the destruction equipment 1030 may contact the second probe 1032 with the second electrode 155 of the semiconductor light emitting device determined to be defective. The first probe 1031 may contact the second bonding layer 132 disposed on the entire area of the transfer substrate 130. For example, the destruction equipment 1030 may supply high voltage to a defective semiconductor light emitting device through the first probe 1031 and the second probe 1032.

As an example, a low level voltage is supplied to the first probe 1031, a high level voltage is supplied to the second probe 1032, and the potential difference between the low level voltage and the high level voltage is applied to the semiconductor light emitting device ( It can have a value greater than the rated voltage of 150). In this case, a constant voltage is supplied to the semiconductor light-emitting device 150, but this constant voltage is much larger than the rated voltage of the semiconductor light-emitting device 150, so the semiconductor light-emitting device 150 may be destroyed.

As another example, a high level voltage is supplied to the first probe 1031, a low level voltage is supplied to the second probe 1032, and the potential difference between the low level voltage and the high level voltage is applied to the semiconductor light emitting device ( It can have a value greater than the rated voltage of 150). In this case, a reverse voltage is supplied to the semiconductor light-emitting device 150, but this reverse voltage may cause physical destruction as well as insulation breakdown of the semiconductor light-emitting device 150.

Accordingly, the defective semiconductor light emitting device is decomposed into fragments or particles by the high voltage supplied from the destruction equipment 1030 and the fragments or particles are collected, thereby removing the defective semiconductor light emitting device.

Thereafter, the normal semiconductor light emitting device is separated from the transfer substrate 130, thereby solving the problem that the normal semiconductor light emitting device and the defective semiconductor light emitting device are mixed and the defective semiconductor light emitting device cannot be removed.

As shown in FIG. 11A, the light emitting part 150a may be grown on the growth substrate 110. The light emitting unit 150a may include a plurality of semiconductor layers. For example, a plurality of semiconductor layers may be deposited on the growth substrate 110 using MOCVD equipment.

The growth substrate 110 is a material that can easily grow a plurality of semiconductor layers, and for example, a sapphire material or a semiconductor material such as GaAs may be used. The growth substrate 110 may be made of a material with excellent durability, insulation, or strength.

The plurality of semiconductor layers may be made of a group 3-5 semiconductor compound material or a group 2-6 semiconductor compound material. The plurality of semiconductor layers may include at least one first conductivity type semiconductor layer, an active layer, and at least one second conductivity type semiconductor layer. First carriers, such as electrons, may be generated in the first conductivity type semiconductor layer, and second carriers, such as holes, may be generated in the second conductivity type semiconductor layer. In the active layer, electrons and holes recombine to generate colored light in a wavelength band determined by the semiconductor compound material of the active layer.

As shown in FIG. 11B, a mesa etching process is performed to etch a plurality of semiconductor layers, thereby forming a plurality of light emitting units 150a separated from each other.

For example, the second electrode 155 may be formed on a plurality of semiconductor layers, and a plurality of photosensitive patterns (not shown) may be formed on the second electrode 155. As the mesa etching process is performed using the plurality of photosensitive patterns as masks, the plurality of semiconductor layers corresponding to the plurality of photosensitive patterns remain without being etched, and a plurality of light emitting units 150a separated from each other may be formed. A plurality of semiconductor layers corresponding to a plurality of photosensitive patterns may be removed.

Thereafter, a passivation layer 157 may be formed to surround each of the plurality of light emitting units 150a. The passivation layer 157 protects the light emitting part 150a, blocks leakage current flowing on the side of the light emitting part 150a, and forms the first conductive semiconductor layer and the second conductive semiconductor layer of the light emitting part 150a. It can prevent electrical short circuit caused by foreign substances. Since the thinner the passivation layer 157 is, the better, considering the semiconductor light emitting device 150 having a size of a micrometer or less, it can be formed thinly using an inorganic material, such as SiNx or SiOx.

A portion of the passivation layer 157 corresponding to the second electrode 155 may be removed to form an opening 158 .

Opening 158 may be formed after first transfer substrate 120 is removed (FIG. 11I).

As shown in FIG. 11C, a first transfer substrate 120 may be prepared, and a first sacrificial layer 121 may be formed on the first transfer substrate 120. The first sacrificial layer 121 is removed by an etching process, and as shown in FIG. 11I, removal of the first sacrificial layer 121 causes the first transfer substrate 120 and other members, such as a semiconductor light emitting device ( 150) can be easily separated. The first sacrificial layer 121 may be made of a polymer material or a photosensitive material, but is not limited thereto.

The first transfer substrate 120 is a temporary substrate for temporarily fixing the plurality of semiconductor light emitting devices 150, and may be made of, for example, sapphire or glass, but is not limited thereto.

The size of the first transfer substrate 120 may be the same as or larger than the size of the growth substrate 110. For example, when the size of the first transfer substrate 120 is the same as the size of the growth substrate 110, the plurality of semiconductor light emitting devices 150 on one sheet of growth substrate 110 remain on one sheet of first transfer substrate 120. can be connected to For example, when the size of the first transfer substrate 120 is larger than the size of the growth substrate 110, the plurality of semiconductor light emitting devices 150 of each of the two or more growth substrates 110 are connected to one sheet of the first transfer substrate 120. ) can be conjugated to.

As shown in FIG. 11D, the growth substrate 110 shown in FIG. 11B and the first transfer substrate 120 shown in FIG. 11C may be bonded.

For example, after the plurality of semiconductor light emitting devices 150 on the growth substrate 110 and the first sacrificial layer 121 on the first transfer substrate 120 are positioned to face each other, heat and pressure are applied to form the first sacrificial layer 121. ) A plurality of semiconductor light emitting devices 150 may be bonded to the first transfer substrate 120 via ).

As shown in FIG. 11E, the growth substrate 110 may be removed using the LLO process, but this is not limited.

That is, when the laser passes through the growth substrate 110 and is irradiated to the interface between the growth substrate 110 and the light emitting unit 150a, the semiconductor layer adjacent to the interface between the growth substrate 110 and the light emitting unit 150a By absorbing the laser, for example, Ga and N are decomposed in GaN, which is a material of the semiconductor layer. At this time, N is evaporated in the form of N2, so the growth substrate 110 can be removed.

As shown in FIG. 11F, the conductive layer 111 and the first bonding layer 112 may be formed on the lower side of the light emitting portion 150a exposed by removing the growth substrate 110.

For example, after the first metal film, the second metal film, and the photosensitive film are formed on the first transfer substrate 120, the photosensitive film may be patterned to form a photosensitive pattern corresponding to each of the plurality of semiconductor light emitting devices 150. there is. An etching process may be performed using the plurality of photosensitive patterns as masks to remove the second metal film and the first metal film. Accordingly, the second metal film and the first metal film that are not etched corresponding to the plurality of photosensitive patterns may become the first bonding layer 112 and the conductive layer 111, respectively.

Unlike FIG. 11F, after the first transfer substrate 120 is flipped 180 degrees, the conductive layer 111 and the first bonding layer 112 may be formed on the light emitting portion 150a.

As shown in FIG. 11G, a second transfer substrate 130 may be prepared, and a second sacrificial layer 131 and a second bonding layer 132 may be formed on the second transfer substrate 130.

The second transfer substrate 130 may be a temporary substrate for temporarily fixing the plurality of semiconductor light emitting devices 150. The second transfer substrate 130 may be made of the same material as the first transfer substrate 120, but this is not limited. For example, the second transfer substrate 130 may be made of sapphire material, glass, etc.

The material of the second sacrificial layer 131 may be different from the material of the first sacrificial layer 121 shown in FIGS. 11C to 11F. That is, when the first sacrificial layer 121 is wet etched and removed by a specific etchant 141, the second sacrificial layer 131 may be made of a material that does not have etch selectivity for the specific etchant 141. That is, the second sacrificial layer 131 is not removed by the specific etchant 141. For example, the second sacrificial layer 131 may be made of an inorganic material, a metal such as Al, Si, or the like.

The second bonding layer 132 may be bonded to the first bonding layer 112 shown in FIG. 11F through eutectic bonding. The material of the second bonding layer 132 may be different from the material of the first bonding layer 112. For example, each of the first bonding layer 112 and the second bonding layer 132 may include at least one of Sn, In, Cu, Au, Ag, Ni, Ti, W, Cr, or Pb, or an alloy thereof. . For example, the first bonding layer 112/second bonding layer 132 includes Sn/Au, Sn/Cu, Sn/Pb, and Au/Si.

The size of the second transfer substrate 130 may be the same as or larger than the size of the first transfer substrate 120. For example, when the size of the second transfer substrate 130 is the same as the size of the first transfer substrate 120, the plurality of semiconductor light emitting devices 150 on one first transfer substrate 120 are transferred as is to one sheet of second transfer substrate 120. It may be bonded to the substrate 130. For example, when the size of the second transfer substrate 130 is larger than the size of the first transfer substrate 120, the plurality of semiconductor light emitting devices 150 on each of the two or more first transfer substrates 120 are one sheet of second transfer substrate 120. It may be bonded to the transfer substrate 130.

As shown in FIG. 11H, the first transfer substrate 120 shown in FIG. 11F and the second transfer substrate 130 shown in FIG. 11G may be bonded.

For example, after the first bonding layer 112 on the first transfer substrate 120 and the second bonding layer 132 on the second transfer substrate 130 are positioned to face each other, eutectic bonding is performed to bond the first bonding layer 112 to the first transfer substrate 130. 120 and the second transfer substrate 130 may be bonded. When heat and pressure are applied by eutectic bonding, the metal made of the material of the first bonding layer 112 and the material of the second bonding layer 132 is formed at the interface of the first bonding layer 112 and the second bonding layer 132. A third bonding layer 133 containing a liver compound may be formed. Accordingly, the first transfer substrate 120 and the second transfer substrate 130 may be bonded to each other by the first bonding layer 112, the second bonding layer 132, and the third bonding layer 133.

As shown in FIG. 11I, the container 140 may be filled with the etchant 141. When the member shown in Figure 11h is put into the container 140, the first sacrificial layer 121 is removed by the etchant 141 in the container 140, so that the first transfer substrate 120 is formed into a plurality of semiconductor light emitting devices. It can be separated from (150). By removing the first sacrificial layer 121, the second electrode 155 of each of the plurality of semiconductor light emitting devices 150 may be exposed to the outside through the opening 158. The container 140 may also be called a chamber, water tank, container, etc.

When the first sacrificial layer 121 is made of a polymer material, the etching 141 is performed using an organic solvent such as a solvent, and the first sacrificial layer 121 can be easily removed using the organic solvent. By removing the first transfer substrate 120, the defect inspection substrate 1000 shown in FIG. 7 can be manufactured.

As shown in FIGS. 9 and 11J, the electrical characteristics of the defect inspection substrate 1000 may be inspected.

The defect inspection substrate 1000 may be placed in a designated location, for example, on a stage. Thereafter, the first probe 1021 and the plurality of

second probes

1022 and 1023 of the PL inspection equipment 1020 may be moved to the defect inspection substrate 1000. Thereafter, the first probe 1021 may contact a point of the edge area of the second bonding layer 132 on the second transfer substrate 130. The plurality of

second probes

1022 and 1023 may each contact the second electrode 155 of the plurality of semiconductor light emitting devices 150. Thereafter, the PL inspection equipment 1020 supplies a predetermined voltage through the first probe 1021 and the

second probe

1022 and 1023, so that the electrical characteristics of each of the plurality of semiconductor light emitting devices 150 can be inspected. .

A normal semiconductor light emitting device 150 and a defective semiconductor light emitting device 150 can be distinguished through inspection of the electrical characteristics of each of the plurality of semiconductor light emitting devices 150.

As shown in FIGS. 10 and 11K, a defective semiconductor light emitting device among the plurality of semiconductor light emitting devices 150 on the second transfer substrate 130 may be removed using the destruction equipment 1030.

After the first probe 1031 and the second probe 1032 of the destruction equipment 1030 are moved to the defect inspection substrate 1000, the first probe 1031 is connected to the second bonding device on the second transfer substrate 130. A point in the edge area of the layer 132 may be contacted, and the second probe 1032 may contact the second electrode 155 of the defective semiconductor light emitting device. Thereafter, high voltage may be supplied to the defective semiconductor light emitting device through the first probe 1031 and the second probe 1032 of the destruction equipment 1030. The defective semiconductor light emitting device is physically broken and decomposed into fragments or particles by the high voltage, and the fragments or particles are collected, thereby allowing the defective semiconductor light emitting device to be removed from the second transfer substrate 130.

Although the second probe 1032 is shown as a single unit in the drawing, a plurality of second probes 1032 may be simultaneously removed by contacting the second electrode 155 of each of the plurality of defective semiconductor light emitting devices at the same time. there is.

As shown in FIG. 11L, an etching process is performed to remove the second bonding layer 132 and the second sacrificial layer 131 between the plurality of semiconductor light emitting devices 150, thereby removing the second bonding layer 132 ) and the second sacrificial layer 131 may be separated from each other. The second bonding layer 132 is partially removed to expose the second sacrificial layer 131 to the outside, and the second sacrificial layer 131 is also separated from each other, so that the second sacrificial layer 131 is more easily removed during the etching process. It can be.

Meanwhile, an etching process may be performed on the second bonding layer 132 to have a large size. That is, the area of the second bonding layer 132 between the plurality of semiconductor light emitting devices 150 can be minimized.

Each of the second bonding layers 132 separated from each other may form a part of the first electrode 154 of each of the plurality of semiconductor light emitting devices 150. The second bonding layer 132, which is part of the first electrode 154 in each of the plurality of semiconductor light emitting devices 150, may be made of metal. Therefore, the larger the size of the second bonding layer 132, the greater the DEP force between the first assembly wiring 321 and the second assembly wiring 322 on the semiconductor light emitting device 150 and the substrate (310 in FIG. 14) during assembly. The area where is formed is expanded, so that the semiconductor light emitting device 150 can be more easily and strongly assembled in the assembly hole 340H, thereby improving the assembly rate.

More details will be described later with reference to FIG. 12.

As shown in FIG. 11M, the container 143 may be filled with the etchant 144. When the member shown in FIG. 11L is put into the container 143, the second sacrificial layer 131 is removed by the etchant 144 in the container 143, so that the second transfer substrate 130 is formed into a plurality of semiconductor light emitting devices. It may be separated from the second bonding layer 132 (150). By removing the second sacrificial layer 131, the second bonding layer 132 of each of the plurality of semiconductor light emitting devices 150 may be exposed to the outside. The container 143 may also be called a chamber, water tank, container, etc.

After collecting the second transfer substrate 130 in the container 143, a plurality of normal semiconductor light emitting devices in the etchant 144 may be extracted and dried.

These plurality of normal semiconductor light emitting devices can be mounted on a display panel through self-assembly and post-processing, which will be described later with reference to FIGS. 13 and 14.

Referring to FIG. 12 , the semiconductor light emitting device 150 according to the first embodiment may include a light emitting portion 150a, a first electrode 154, a second electrode 155, and a passivation layer 157.

The semiconductor light emitting device 150 according to the first embodiment may be a normal semiconductor light emitting device manufactured through a series of processes shown in FIGS. 11A to 11M. Here, a normal semiconductor light-emitting device refers to a semiconductor light-emitting device that has been tested for electrical characteristics using the PL inspection equipment 1020 shown in FIG. 11J during a series of processes and is determined to be normal by meeting preset standards.

As described above, the light emitting unit 150a includes a plurality of semiconductor layers and can generate light of a specific color.

The second electrode 155 is a transparent electrode layer 155-1, and light generated in the light emitting unit 150a can pass through the second electrode 155 and be emitted forward.

Meanwhile, the first electrode 154 may include multiple layers. The first electrode 154 may include a conductive layer 111 and

bonding layers

112, 133, and 132. For example, the conductive layer 111 may be disposed under the light emitting unit 150a, and the bonding layers 112, 133, and 132 may be disposed under the conductive layer 111.

In an embodiment, some of the layers 132 of the plurality of layers constituting the bonding layers 112, 133, and 132 may have a diameter D2 larger than the diameter D1 of the light emitting portion 150a.

Specifically, the bonding layer may include a first bonding layer 112, a second bonding layer 132, and a third bonding layer 133.

The first bonding layer 112 is disposed below the light emitting portion 150a, the second bonding layer 132 is disposed under the first bonding layer 112, and the third bonding layer 133 is disposed under the first bonding layer. It may be disposed between (112) and the second bonding layer (132).

The first bonding layer 112 and the second bonding layer 132 are made of a material with excellent bonding properties, and may include different materials, but are not limited thereto. For example, each of the first bonding layer 112 and the second bonding layer 132 may include at least one of Sn, In, Cu, Au, Ag, Ni, Ti, W, Cr, or Pb, or an alloy thereof. . For example, the first bonding layer 112/second bonding layer 132 includes Sn/Au, Sn/Cu, Sn/Pb, and Au/Si.

The third bonding layer 133 is an intermetallic compound made of the material of the first bonding layer 112 and the material of the second bonding layer 132 at the interface of the first bonding layer 112 and the second bonding layer 132. may include. That is, when eutectic bonding is performed, the material of the first bonding layer 112 and the material of the second bonding layer 132 are uniformly distributed at the boundary between the first bonding layer 112 and the second bonding layer 132. A third bonding layer 133 containing an intermetallic compound may be formed.

For example, the second bonding layer 132 may have a diameter D2 that is larger than the diameter D1 of the light emitting portion 150a. For example, the second bonding layer 132 may have a diameter D2 that is larger than the diameter D3 of at least one of the first bonding layer 112 and the third bonding layer 133. The first bonding layer 112 and the third bonding layer 133 may have the same diameter D3.

The second bonding layer 132 may include a protrusion 132a that protrudes outward from the side of the light emitting unit 150a. The protrusion 132a may protrude in an outward direction from a side of at least one of the first bonding layer 112 or the third bonding layer 133. The second bonding layer 132 may have a first area that vertically overlaps the light emitting unit 150a and a second area that does not vertically overlap the light emitting unit 150a. The second area may surround the first area. The second area may be a protrusion 132a.

According to the embodiment, by expanding the size of the second bonding layer 132, as shown in FIG. 14, when a DEP force is formed in the assembly hole on the substrate during self-assembly, the second bonding layer 132 is formed within the assembly hole. ) The semiconductor light emitting device 150 can be fixed in the assembly hole by a DEP force of a size of ). Accordingly, by expanding the size of the second bonding layer 132, when the semiconductor light emitting device 150 is assembled and fixed in the assembly hole, it does not fall out of the assembly hole again, thereby improving the assembly rate.

In addition, according to the embodiment, as shown in FIG. 14, when the sides of the semiconductor light emitting device 150 are electrically connected by the connection electrode, the connection electrode is connected to the upper surface of the further expanded second bonding layer 132 and the By being connected to the side, electrical connection can be facilitated. In addition, the contact area between the connection electrode and the side of the semiconductor light emitting device 150 is increased, allowing smooth current flow and improving luminance.

Figure 13 is a plan view showing a display device including a semiconductor light-emitting device according to the first embodiment. FIG. 14 is a cross-sectional view taken along line C1-C2 of the first sub-pixel in the display device according to the embodiment of FIG. 12.

13 and 14, the display device 300 according to the embodiment includes a substrate 310, a plurality of first assembly wirings 321, a plurality of second assembly wirings 322, a partition wall 340, and a plurality of partition walls 340. It may include semiconductor light emitting devices 150-1, 150-2, and 150-3 and a plurality of connection electrodes 370.

A plurality of sub-pixels (PX1, PX2, and PX3) may be arranged on the substrate 310.

The plurality of sub-pixels may include a plurality of first sub-pixels (PX1) arranged along the first direction (X). Each of the plurality of first sub-pixels PX1 may emit the same color light, that is, the first color light.

For example, the plurality of sub-pixels may include a plurality of second sub-pixels (PX2) adjacent to each of the plurality of first sub-pixels (PX1) along the second direction (Y) and arranged along the first direction (X). You can. Each of the plurality of second sub-pixels PX2 may emit the same color light, that is, the second color light.

For example, the plurality of sub-pixels may include a plurality of third sub-pixels (PX3) adjacent to each of the plurality of second sub-pixels (PX2) along the second direction (Y) and arranged along the first direction (X). You can. The plurality of third sub-pixels PX3 may emit the same color light, that is, a third color light.

The first color light may be red light, the second color light may be green light, and the third color light may be blue light, but there is no limitation thereto. The first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) arranged along the second direction (Y) may form a unit pixel capable of displaying a full color image. Accordingly, by arranging a plurality of unit pixels on the substrate 310, a large-area image can be displayed.

As shown in FIG. 14, the first sub-pixel (PX1) includes the first assembly wiring 321, the second assembly wiring 322, the assembly hole 340H, the first semiconductor light emitting device 150-1, and the connection It may include an electrode 370 and an electrode wire 362. Although not shown, the second sub-pixel (PX2) and the third sub-pixel (PX3) may also include the components of the first sub-pixel (PX1).

Although not shown, the second sub-pixel (PX2) and the third sub-pixel (PX3) may also include the components shown in FIG. 14. However, the second semiconductor light-emitting device 150-2 may be disposed in the second sub-pixel PX2, and the third semiconductor light-emitting device 150-3 may be disposed in the third sub-pixel PX3.

The substrate 310 may be a support member that supports components disposed on the substrate 310 or a protection member that protects the components. Since the substrate 310 has been previously described, it is omitted.

The first and

second assembly wirings

321 and 322 may be disposed on the substrate 310 . That is, the plurality of sub-pixels PX1, PX2, and PX3 may each include a first assembly wiring 321 and a second assembly wiring 322. The first and

second assembly wires

321 and 322 may serve to assemble the semiconductor light emitting device 150-1 into the assembly hole 340H in a self-assembly method. That is, during self-assembly, an electric field is generated between the first assembly wiring 321 and the second assembly wiring 322 by the voltage supplied to the first and

second assembly wirings

321 and 322, and the electric field formed by this electric field The semiconductor light emitting device 150-1, which is moving, may be assembled in the assembly hole 340H by an assembly device (1100 in FIG. 10) by dielectrophoresis force.

The same assembly wiring for each of the plurality of sub-pixels (PX1, PX2, and PX3) may be formed integrally. For example, the second assembly wiring 322 of the first sub-pixel PX1 may be formed integrally with the second assembly wiring 322 of the second sub-pixel PX2. For example, the first assembly wiring 321 of the second sub-pixel PX2 may be formed integrally with the first assembly wiring 321 of the third sub-pixel PX3.

The first assembly wiring 321 and the second assembly wiring 322 may be arranged on the same layer. That is, the first assembly wiring 321 and the second assembly wiring 322 may be disposed between the substrate 310 and the first insulating layer 320 . In this case, the first assembly wiring 321 and the second assembly wiring 322 may be arranged to be spaced apart from each other to prevent electrical short circuits.

In the drawing, the first assembly wiring 321 and the second assembly wiring 322 are shown as being disposed on the same layer, but they may be disposed on different layers.

For example, the first assembled wire 321 may be placed under the first insulating layer 320, and the second assembled wire 322 may be placed on the first insulating layer 320. In this case, the upper surface of the second assembly wiring 322 may be exposed to the outside, that is, to the assembly hole 340H. For example, the second assembly wiring 322 may form part of the bottom of the assembly hole 340H. When the semiconductor light emitting device 150-1 is assembled in the assembly hole 340H, the lower side of the semiconductor light emitting device 150-1 may be in contact with the upper surface of the second assembly wiring 322 in the assembly hole 340H. .

Referring again to FIG. 12 , the first insulating layer 320 may be disposed on the first assembled wiring 321 and the second assembled wiring 322 . For example, the first insulating layer 320 can prevent the first assembly wiring 321 and the second assembly wiring 322 from being electrically short-circuited by foreign substances. For example, the first insulating layer 320 is made of a material with a dielectric constant and may contribute to the formation of dielectrophoretic force. For example, the first insulating layer 320 may be made of an inorganic material or an organic material. For example, the first insulating layer 320 may be made of a material having a dielectric constant related to the dielectrophoretic force.

The partition 340 is disposed on the substrate 310 and may have an assembly hole 340H. Each of the plurality of sub-pixels PX1, PX2, and PX3 may include at least one assembly hole 340H. The partition wall 340 may be disposed on the first assembly wiring 321 and the second assembly wiring 322. For example, the assembly hole 340H may be provided on the first assembly wiring 321 and the second assembly wiring 322. The thickness of the partition wall 340 may be determined by considering the thickness of the semiconductor light emitting device 150-1. For example, the thickness of the partition wall 340 may be smaller than the thickness of the semiconductor light emitting device 150-1. Accordingly, the upper side of the semiconductor light emitting device 150-1 may be positioned higher than the upper surface of the partition wall 340. That is, the upper side of the semiconductor light emitting device 150-1 may protrude upward from the upper surface of the partition wall 340.

A plurality of semiconductor light emitting devices (150-1, 150-2, 150-3) Each can be assembled in the assembly hole 340H. For example, one semiconductor light emitting device may be assembled in the assembly hole 340H.

Considering the tolerance margin for forming the assembly hole 340H and the margin for easily assembling the semiconductor light emitting devices 150-1, 150-2, and 150-3 within the assembly hole 340H, the assembly hole 340H ) can be determined. For example, the size of the assembly hole 340H may be larger than the size of the semiconductor light emitting devices 150-1, 150-2, and 150-3. For example, when the semiconductor light emitting devices 150-1, 150-2, and 150-3 are assembled in the center of the assembly hole 340H, the outer sides of the semiconductor light emitting devices 150-1, 150-2, and 150-3 The distance between the inner sides of the assembly hole 340H may be 2 μm or less, but is not limited thereto.

For example, the assembly hole 340H may have a shape corresponding to the shape of the semiconductor light emitting devices 150-1, 150-2, and 150-3. For example, when the semiconductor light emitting devices 150-1, 150-2, and 150-3 are circular, the assembly hole 340H may also be circular. For example, when the semiconductor light emitting devices 150-1, 150-2, and 150-3 are rectangular, the assembly hole 340H may also be rectangular.

As an example, the assembly hole 340H in each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) may have the same shape, that is, a circular shape. In this case, the first semiconductor light-emitting device 150-1 disposed in the first sub-pixel PX1, the second semiconductor light-emitting device 150-2 disposed in the second sub-pixel PX2, and the third sub-pixel ( The third semiconductor light emitting device 150-3 disposed in PX3) may have a shape corresponding to the assembly hole 340H, that is, a circular shape.

As such, when the assembly hole 340H in each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) has the same shape, the first semiconductor light emitting device 150-1 ), each of the second semiconductor light emitting device 150-2 and the third semiconductor light emitting device 150-3 may be sequentially assembled in the assembly hole 340H of each of the corresponding sub-pixels (PX1, PX2, and PX3). , there is no limitation to this. For example, the first semiconductor light emitting device 150-1 is assembled in the assembly hole 340H of the first sub-pixel PX1 of the substrate 310, and the second semiconductor light emitting device 150-2 is assembled into the substrate 310. is assembled into the assembly hole 340H of the second sub-pixel PX2, and the third semiconductor light emitting device 150-3 is assembled into the assembly hole 340H of the third sub-pixel PX3 of the substrate 310. You can. In this case, the shapes of the first semiconductor light-emitting device 150-1, the second semiconductor light-emitting device 150-2, and the third semiconductor light-emitting device 150-3 may be the same, but this is not limited. Each of the assembly holes 340H has a shape corresponding to the shape of each of the first semiconductor light-emitting device 150-1, the second semiconductor light-emitting device 150-2, and the third semiconductor light-emitting device 150-3, It may have a size larger than each of the first semiconductor light-emitting device 150-1, the second semiconductor light-emitting device 150-2, and the third semiconductor light-emitting device 150-3.

As another example, the assembly hole 340H in each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) may have a different shape. For example, the assembly hole 340H in the first sub-pixel PX1 has a circular shape, and the assembly hole 340H in the second sub-pixel PX2 has a first oval shape with a first minor axis and a first major axis. , the assembly hole 340H in the third sub-pixel PX3 may have a second oval shape with a second minor axis smaller than the first minor axis and a second major axis larger than the first major axis. In this case, the first semiconductor light emitting device 150-1 has a shape corresponding to the assembly hole 340H of the first sub-pixel PX1, that is, a circular shape, and the second semiconductor light emitting device 150-2 has a second semiconductor light emitting device 150-2. It has a shape corresponding to the assembly hole 340H of the sub-pixel PX2, that is, a first oval shape, and the third semiconductor light emitting device 150-3 has a shape corresponding to the assembly hole 340H of the third sub-pixel PX3. It may have a shape, that is, a second oval shape.

In this way, the assembly holes 340H having different shapes and the first to third semiconductor light emitting devices 150-1, 150-2, and 150-3 having shapes corresponding to each of the assembly holes 340H. As a result, the first to third semiconductor light emitting devices 150-1, 150-2, and 150-3 can be simultaneously assembled in the corresponding assembly hole 340H during self-assembly. That is, even if the first semiconductor light emitting device 150-1, the second semiconductor light emitting device 150-2, and the third semiconductor light emitting device 150-3 are mixed in the fluid 1200 for self-assembly, the semiconductor light emitting device on the substrate Semiconductor devices corresponding to the assembly holes 340H of each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) may be assembled. That is, the first semiconductor light emitting device 150-1 having a shape corresponding to the shape of the assembly hole 340H may be assembled into the assembly hole 340H of the first sub-pixel PX1. A second semiconductor light emitting device 150-2 having a shape corresponding to the shape of the assembly hole 340H may be assembled into the assembly hole 340H of the second sub-pixel PX2. A third semiconductor light emitting device 150-3 having a shape corresponding to the shape of the assembly hole 340H may be assembled in the assembly hole 340H of the third sub-pixel PX3. Therefore, each of the first semiconductor light emitting device 150-1, the second semiconductor light emitting device 150-2, and the third semiconductor light emitting device 150-3, which have different shapes, has an assembly hole ( Since it is assembled at 340H), assembly defects can be prevented.

Meanwhile, the plurality of semiconductor light emitting devices include a first semiconductor light emitting device 150-1 that emits a first color light, a second semiconductor light emitting device 150-2 that emits a second color light, and a third color light emitting device. It may include a third semiconductor light emitting device 150-3. For example, at least one first semiconductor light emitting device 150-1 may be disposed in each of the plurality of first sub-pixels PX1 arranged along the first direction. For example, at least one second semiconductor light emitting device 150-2 may be disposed in each of the plurality of second sub-pixels PX2 arranged along the first direction. For example, at least one third semiconductor light emitting device 150-3 may be disposed in each of the plurality of third sub-pixels PX3 arranged along the first direction.

Meanwhile, the connection electrode 370 may be disposed in the assembly hole 350H. For example, the connection electrode 370 may be disposed around the semiconductor light emitting devices 10-1, 150-2, and 150-3 within the assembly hole 370H.

The thickness of the connection electrode 370 may be smaller than the thickness of the partition wall 340, but this is not limited.

The connection electrode 370 may be connected to the first electrode 154 of the first semiconductor light emitting device 150-1 of the first sub-pixel PX1.

As described above, the first electrode 154 includes bonding layers 112, 132, and 133, and some of the bonding layers 112, 132, and 133 have a diameter (132) of the light emitting portion 150a. It may have a diameter (D2) larger than D1). That is, the bonding layer includes a first bonding layer 112, a second bonding layer 132, and a third bonding layer 133, of which the second bonding layer 132 is the diameter of the light emitting portion 150a ( It may have a diameter (D2) larger than D1).

The connection electrode 370 may be connected to the conductive layer 111, which is part of the first electrode 154. The connection electrode 370 may be connected to the bonding layers 112, 132, and 133. In particular, the connection electrode 370 may be connected to the side and top surfaces of the second bonding layer 132 along the outer peripheral surface of the second bonding layer 132.

According to the embodiment, the connection electrode 370 is connected to the conductive layer 111, the first bonding layer 112, the second bonding layer 132, and the third bonding layer 133 to form a connection between the connection electrode 370 and the third bonding layer 133. The connection area between the first electrodes 154 is increased to improve current flow, thereby increasing luminance.

According to the embodiment, the connection electrode 370 is in contact with the conductive layer 111, the first bonding layer 112, the second bonding layer 132, and the third bonding layer 133, so that the connection electrode 370 and the third bonding layer 133 are connected to each other. The contact area between the first electrodes 154 is increased, thereby strengthening the fixation of the first semiconductor light emitting device 150-1, thereby improving product reliability.

In particular, by expanding the size of the second bonding layer 132, the connection area with the connection electrode 370 increases, thereby further increasing luminance, and the contact area with the connection electrode 370 increases, thereby forming the first semiconductor light emitting device. The fixity of (150-1) can be further strengthened.

According to the embodiment, by expanding the size of the second bonding layer 132, self-assembly is performed to assemble the first semiconductor light emitting device 150-1 into the assembly hole 340H on the substrate 310, thereby performing DEP force. may be formed in the assembly hole 340H on the substrate 310. At this time, the first semiconductor light emitting device 150-1 may be fixed within the assembly hole 340H by a DEP force equal to the size of the second bonding layer 132 within the assembly hole 340H. Accordingly, by expanding the size of the second bonding layer 132, when the first semiconductor light emitting device 150-1 is assembled and fixed within the assembly hole 340H, it does not fall out of the assembly hole 340H again, thereby reducing the assembly rate. It can be improved.

Although not shown, the connection electrode 370 may also be connected to the second semiconductor light-emitting device 150-2 of the second sub-pixel (PX2) or the third semiconductor light-emitting device 150-3 of the third sub-pixel (PX3). there is. The second semiconductor light emitting device 150-2 or the third semiconductor light emitting device 150-3 may have the same structure as the first semiconductor light emitting device 150-1 except for the shape.

In addition, the connection electrode 370 is disposed along the circumference of the semiconductor light emitting devices 150-1, 150-2, and 150-3 within the assembly hole 340H, so that the connection electrode 370 connects the partition wall 340 and The semiconductor light emitting devices 150-1, 150-2, and 150-3 are firmly fixed, so that fixation can be strengthened.

Meanwhile, the second insulating layer 350 is disposed on the partition wall 340 to protect the semiconductor light emitting device 150-1. The second insulating layer 350 is disposed in the assembly hole 340H around the semiconductor and can firmly fix the semiconductor light emitting device 150-1. Additionally, the second insulating layer 350 is disposed on the semiconductor light-emitting device 150-1 to protect the semiconductor light-emitting device 150-1 from external shocks and prevent contamination by foreign substances.

The second insulating layer 350 may serve as a planarization layer that allows a layer formed in a later process to be formed at a constant thickness. Accordingly, the upper surface of the second insulating layer 350 may have a flat surface. The second insulating layer 350 may be formed of an organic material or an inorganic material. Accordingly, the electrode wiring 362 can be easily formed on the upper surface of the second insulating layer 350 having a flat surface without disconnection.

A plurality of electrode wires 362 may be disposed on the upper side of each of the plurality of semiconductor light emitting devices 150-1, 150-2, and 150-3. Each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) may include an electrode wire 362.

For example, the electrode wire 362 may be disposed above the first semiconductor light emitting device 150-1 disposed in the first sub-pixel PX1. The electrode wire 362 may be connected to the second side of the first semiconductor light emitting device 150-1 through the contact hole 350H2. For example, the first electrode wire 362 may be disposed above the second semiconductor light emitting device 150-2 disposed in the second sub-pixel PX2. The electrode wire 362 may be connected to the second side of the second semiconductor light emitting device 150-2 through the contact hole 350H2. For example, the electrode wire 362 may be disposed above the third semiconductor light emitting device 150-3 disposed in the third sub-pixel PX3. The electrode wire 362 may be connected to the second side of the third semiconductor light emitting device 150-3 through the contact hole 350H2.

The electrode wire 362 may be disposed on the second insulating layer 350 . For example, the electrode wiring 362 may be made of a transparent conductive material that allows light to pass through. For example, the electrode wiring 362 may include ITO, IZO, etc., but is not limited thereto.

Meanwhile, the first assembled wiring 321 and/or the second assembled wiring 322 may be used as the first electrode wiring, and the electrode wiring 362 may be used as the second electrode wiring. Accordingly, the first semiconductor light emitting device 150-1 emits first color light, for example, red, by the voltage applied between the first assembly wiring 321 and/or the second assembly wiring 322 and the electrode wiring 362. Can emit light.

Meanwhile, the display device 300 according to the embodiment may include a plurality of signal lines SL1, SL2, SL3, and SL4. The plurality of signals may include a first signal line (SL1), a second signal line (SL2), a third signal line (SL3), and a fourth signal line (SL4). A plurality of signal lines (SL1, SL2, SL3, and SL4) may be arranged on the same layer.

The plurality of signal lines SL1, SL2, SL3, and SL4 may be disposed on a different layer from the electrode wiring 362. Accordingly, the plurality of signal lines (SL1, SL2, SL3, and SL4) and the electrode wire 362 may be electrically connected through the plurality of contact holes (351H1, 351H2, and 351H3). For example, the first signal line SL1 and the electrode wire 362 may be electrically connected through the first contact hole 351H1. For example, the second signal line SL2 and the electrode wire 362 may be electrically connected through the second contact hole 351H2. For example, the third signal line SL3 and the electrode wire 362 may be electrically connected through the third contact hole 351H3. For example, the fourth signal line SL4 and the first assembly wiring 321 and/or the second assembly wiring 322 may be electrically connected through the contact hole 352.

The plurality of signal lines SL1, SL2, SL3, and SL4 may be disposed on a different layer from the first and second assembled

wirings

321 and 322.

Meanwhile, the first signal line SL1 may be electrically connected to a plurality of first sub-pixels PX1. For example, the first signal line SL1 may be electrically connected to the second electrode 155 of the first semiconductor light emitting device 150-1 through the electrode wiring 362 of each of the plurality of first sub-pixels PX1. there is.

The second signal line SL2 may be electrically connected to a plurality of second sub-pixels PX2. For example, the second signal line SL2 may be electrically connected to the second electrode 155 of the second semiconductor light emitting device 150-2 through the electrode wiring 362 of each of the plurality of second sub-pixels PX2. there is.

The third signal line SL3 may be electrically connected to a plurality of third sub-pixels PX3. For example, the third signal line SL3 may be electrically connected to the second electrode 155 of the third semiconductor light emitting device 150-3 through the electrode wiring 362 of each of the plurality of third sub-pixels PX3. there is.

The fourth signal line SL4 may be commonly connected to the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3). For example, the fourth signal line SL4 is connected to the first assembly line 321 of the first sub-pixel PX1 and/or the second assembly line 322 of the first semiconductor light emitting device 150-1. It may be electrically connected to the electrode 154. For example, the fourth signal line SL4 is connected to the first assembly line 321 of the second sub-pixel PX2 and/or the second assembly line 322 of the second semiconductor light emitting device 150-2. It may be electrically connected to the electrode 154. For example, the fourth signal line SL4 is connected to the first assembly line 321 of the third sub-pixel PX3 and/or the second assembly line 322 of the third semiconductor light emitting device 150-3. It may be electrically connected to the electrode 154.

For example, a positive (+) voltage may be supplied to each of the first signal line (SL1), the second signal line (SL2), and the third signal line (SL3). For example, the fourth signal line SL4 may be grounded or supplied with a negative (-) voltage. The positive (+) voltage supplied to each of the first signal line (SL1), the second signal line (SL2), and the third signal line (SL3) may be the same, but this is not limited.

For example, the first signal line SL1 connected to the first sub-pixel PX1 may be the high potential voltage line VDDL shown in FIG. 7 . For example, the second signal line (SL2) connected to the second sub-pixel (PX2) and the third signal line (SL3) connected to the third sub-pixel (PX3) also serve as a high-potential signal line (VDDL), and a high-potential voltage (Figure A VDD of 6) can be supplied. For example, the fourth signal line SL4 commonly connected to each of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) is a low-potential signal line (VSSL), and is a low-potential voltage (VSS in FIG. 6) may be supplied.

Although not shown in the drawing, the first semiconductor light emitting device 150-1 of the first signal line SL1 and the first sub-pixel PX1, the first semiconductor light emitting device 150-1 of the second signal line SL2 and the second sub-pixel PX2 2 A driving transistor (DT in FIG. 7) may be provided between the semiconductor light emitting device 150-2 and the third signal line SL3 and the third semiconductor light emitting device 150-3 of the third sub-pixel PX3. there is. At this time, the gate terminal of the driving transistor (DT) may be connected to the data line (Dj) through the scan transistor (ST).

Accordingly, the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) each include a scan transistor (ST), a driving transistor (DT), and a semiconductor light emitting device (150-1, 150-2). , 150-3) may be provided. At this time, the driving transistor DT may be connected to the scan transistor ST and the semiconductor light emitting devices 150-1, 150-2, and 150-3, and the scan transistor ST may be connected to the data line Dj. The driving transistors (ST) of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) are connected to the high potential signal line (VDDL), that is, the first to third signal lines (SL1, It can be connected to SL2, SL3). The semiconductor light emitting elements 150-1, 150-2, and 150-3 of the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel (PX3) each have a low potential signal line (VSSL), That is, it may be connected to the fourth signal line SL4.

The current flowing in the driving transistor (ST) varies depending on the data voltage supplied to the data line (Dj), and this different current causes the first sub-pixel (PX1), the second sub-pixel (PX2), and the third sub-pixel The intensity of light, that is, the luminance or gradation, of each of the semiconductor light emitting devices 150-1, 150-2, and 150-3 of (PX3) is different, so that images with different brightnesses can be displayed.

[Second Embodiment]

Figure 15 is a cross-sectional view showing a defect inspection substrate according to the second embodiment.

The second embodiment is the same as the first embodiment (FIG. 7) except for the conductive protective layer 155-2 included in the second electrode 155. In the second embodiment, components having the same structure, shape, and/or function as those of the first embodiment are assigned the same reference numerals and detailed descriptions are omitted. Descriptions omitted below can be easily understood from the first embodiment (FIGS. 7 to 14).

Referring to FIG. 15 , the defect inspection substrate 1001 according to the second embodiment may include a transfer substrate 130 and a plurality of semiconductor light emitting devices 150A.

The transfer substrate 130 may serve to temporarily support the plurality of semiconductor light emitting devices 150A to inspect the electrical characteristics of each of the plurality of semiconductor light emitting devices 150A disposed thereon.

A plurality of semiconductor light emitting devices 150A may be bonded to the transfer substrate 130 through

bonding layers

112, 132, and 133.

For example, a plurality of semiconductor light emitting devices 150A, each including a light emitting portion 150a, a second electrode 155, a conductive layer 111, and a first bonding layer 112, may be positioned on the transfer substrate 130. You can. At this time, the second bonding layer 132 may be disposed on the entire area of the transfer substrate 130. Eutectic bonding is performed and heat and pressure are applied to the plurality of semiconductor light emitting devices 150A, thereby forming a third bonding layer 133 between the first bonding layer 112 and the second bonding layer 132. A plurality of semiconductor light emitting devices 150A may be bonded to the transfer substrate 130 by the first bonding layer 112 and the second bonding layer 132 along with the third bonding layer 133 . The third bonding layer 133 may include an intermetallic compound made of the material of the first bonding layer 112 and the material of the second bonding layer 132.

Meanwhile, the second electrode 155 may include a transparent electrode layer 155-1 and a conductive protective layer 155-2.

The transparent electrode layer 155-1 may serve as an electrode layer for injecting current and as a transmission layer for transmitting light generated in the light emitting unit 150a. For example, the transparent electrode layer 155-1 may include a transparent conductive material, such as ITO.

The conductive protective layer 155-2 can prevent the transparent electrode layer 155-1 from being scratched or damaged when inspecting the electrical characteristics of each of the plurality of semiconductor light emitting devices 150A. there is.

That is, as shown in FIG. 16, the

second probes

1022 and 1023 of the PL inspection equipment 1020 are contacted with the second electrodes 155 of each of the plurality of semiconductor light emitting devices 150A to inspect the electrical characteristics. You can. At this time, a certain pressure may be applied to the

second probes

1022 and 1023 to smoothly supply signals.

When pressure is applied to one point of the transparent electrode layer 155-1 made of ITO or the like, scratches may easily occur or the transparent electrode layer 155-1 may be damaged. Therefore, since the conductive protective layer 155-2 is not provided, the

second probes

1022 and 1023 are directly contacted to one point of the transparent electrode layer 155-1, and then the transparent electrode layer is exposed by the

second probes

1022 and 1023. When a certain pressure is applied to (155-1), scratches may occur on the transparent electrode layer (155-1) or the transparent electrode layer (155-1) may be damaged.

However, as in the embodiment, the conductive protective layer 155-2 is disposed on the transparent electrode layer 155-1, so that the

second probes

1022 and 1023 only contact the conductive protective layer 155-2. Since there may not be contact with the transparent electrode layer 155-1, scratches may not occur on the transparent electrode layer 155-1 or the transparent electrode layer 155-1 may not be damaged.

Since the conductive protective layer 155-2 must supply current, it can be made of a material with excellent electrical conductivity. The conductive protective layer 155-2 may be made of a material that has excellent strength and is not scratched or damaged by the pressure exerted by the

second probes

1022 and 1023. For example, the conductive protective layer 155-2 may be a carbon nanotube-polyimide composite film or a graphene-polyimide composite film. Carbon nanotube-polyimide composite film or graphene-polyimide composite film has excellent electrical conductivity, is transparent, and is durable. Therefore, when the conductive protective layer 155-2, which is a carbon nanotube-polyimide composite film or a graphene-polyimide composite film, is used, the contact of the

second probes

1022 and 1023 or the second probes 1022 and 1023 ) Even if pressure is applied, scratches do not occur on the conductive protective layer (155-2) and the conductive protective layer (155-2) is not damaged, and the transparent electrode layer disposed under the conductive protective layer (155-2) (155-1) may be protected from the

second probes

1022 and 1023.

Although not shown, the second electrode 155 may include a single layer made of the conductive protective layer 155-2 instead of the double layer of the transparent electrode layer 155-1 and the conductive protective layer 155-2.

As shown in FIG. 16, the first probe 1021 of the PL inspection equipment 1020 contacts a point at the edge of the second bonding layer 132, and the

second probes

1022 and 1023 are connected to a plurality of semiconductors. Each light emitting device 150A may be in contact with the second electrode 155, that is, the conductive protective layer 155-2. I-V characteristics or reverse current characteristics are tested by detecting the current for the voltage supplied by the PL test equipment 1020, and based on these test results, it can be determined whether each of the plurality of semiconductor light emitting devices 150A is defective. As described above, the semiconductor light emitting device 150A determined to be defective may be decomposed into fragments or particles and then collected and removed.

According to an embodiment, in the second electrode 155 of the semiconductor light emitting device 150A, a conductive protective layer 155-2 capable of protecting the transparent electrode layer 155-1 is formed on the transparent electrode layer 155-1. By this arrangement, even if the

second probes

1022 and 1023 of the PL inspection equipment 1020 contact the conductive protective layer 155-2 and apply pressure, the transparent electrode layer 155 is maintained by the conductive protective layer 155-2. -1) may be scratched or the transparent electrode layer 155-1 may not be damaged. Accordingly, deterioration of electrical or optical properties caused by scratches or damage to the transparent electrode layer 155-1 can be prevented.

The second embodiment is the same as the first embodiment (FIG. 12) except for the conductive protective layer 155-2 included in the second electrode 155. In the second embodiment, components having the same structure, shape, and/or function as those of the first embodiment are assigned the same reference numerals and detailed descriptions are omitted. Descriptions omitted below can be easily understood from the first embodiment (FIGS. 7 to 14).

The semiconductor light emitting device 150A according to the second embodiment shown in FIG. 17 includes a second bonding layer 132 disposed on the entire area of the transfer substrate 130 in the defect inspection substrate 1001 shown in FIG. 15. This may be one of the plurality of semiconductor light emitting devices 150A manufactured by partially removing and separating them from each other and then removing the transfer substrate 130 by etching the sacrificial layer 131.

The semiconductor light emitting device 150A according to the second embodiment may include a light emitting portion 150a, a first electrode 154, a second electrode 155, and a passivation layer 157.

Since the light emitting unit 150a, the first electrode 154, and the passivation layer 157 have been described previously, detailed descriptions are omitted. Since the second electrode 155 has also been described in the technical content related to FIG. 15, detailed description will be omitted.

The second embodiment is the same as the first embodiment (FIG. 14) except that the second electrode 155 of the semiconductor light emitting device 150-1 is composed of double layers 155-1 and 155-2. In the second embodiment, components having the same structure, shape, and/or function as those of the first embodiment are assigned the same reference numerals and detailed descriptions are omitted. Descriptions omitted below can be easily understood from the first embodiment (FIGS. 7 to 14).

Referring to FIG. 18, the display device 301 according to the second embodiment includes a substrate 310, a plurality of first assembly wirings 321, a plurality of second assembly wirings 322, a partition 340, and a semiconductor light emitting device. It may include (150-1) and a plurality of connection electrodes 370.

The semiconductor light-emitting device 150-1 includes the first semiconductor light-emitting device 150-2 of the first sub-pixel PX1 shown in Figure 13, the second semiconductor light-emitting device 150-2 of the second sub-pixel PX2, and the third sub-pixel. It may be the first semiconductor light emitting device 150-1 among the third semiconductor light emitting devices 150-3 of (PX3). The second semiconductor light emitting device 150-2 and/or the third semiconductor light emitting device 150-3 may have the same structure as the first semiconductor light emitting device 150-1 except for the shape.

The semiconductor light emitting device 150-1 may be the semiconductor light emitting device 150A shown in FIG. 17.

The semiconductor light emitting device 150-1 may include a light emitting portion 150a, a first electrode 154, a second electrode 155, and a passivation layer 157.

The second electrode 155 may be composed of a double layer of a transparent electrode layer 155-1 and a conductive protective layer 155-2, but this is not limited.

The electrode wire 362 may be connected to the conductive protective layer 155-2 of the second electrode 155 through the second insulating layer 350. Since the conductive protective layer 155-2 is a carbon nanotube-polyimide composite film or a graphene-polyimide composite film with very excellent electrical conductivity, the voltage provided to the electrode wiring 362 is applied to the conductive protective layer 155-2. Since the light is smoothly supplied to the light emitting unit 150a through the light emitting unit 150a, the amount of light in the light emitting unit 150a increases and the luminance can be improved.

Meanwhile, the display device described above may be a display panel. That is, in the embodiment, the display device and the display panel may be understood to have the same meaning. In an embodiment, a display device in a practical sense may include a display panel and a controller (or processor) capable of controlling the display panel to display an image.

The above detailed description should not be construed as restrictive in any respect and should be considered illustrative. The scope of the embodiments should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the embodiments are included in the scope of the embodiments.

Embodiments may be adopted in the field of displays that display images or information. Embodiments may be adopted in the field of displays that display images or information using semiconductor light-emitting devices. The semiconductor light-emitting device may be a micro-level semiconductor light-emitting device or a nano-level semiconductor light-emitting device.

For example, embodiments can be adopted in TVs, signage, smart phones, mobile phones, mobile terminals, HUDs for automobiles, backlight units for laptops, and display devices for VR or AR.

Claims

transfer substrate; and

It includes a plurality of semiconductor light emitting devices spaced apart from each other on the transfer substrate,

Each of the plurality of semiconductor light emitting devices,

light emitting part;

a first electrode including a plurality of first layers below the light emitting unit;

a second electrode on the light emitting unit; and

It includes a passivation layer surrounding the light emitting part,

At least one first layer among the plurality of first layers of the first electrode is a common layer that commonly connects each of the plurality of semiconductor light emitting devices.

Board for defect inspection.
According to paragraph 1,

The common layer is,

Having an area larger than the total area of the plurality of semiconductor light emitting devices

Board for defect inspection.
According to paragraph 1,

The second electrode includes a plurality of second layers,

The highest layer of the plurality of second layers of the second electrode is a conductive protective layer.

Board for defect inspection.
light emitting part;

a first electrode including a plurality of first layers below the light emitting unit;

a second electrode on the light emitting unit; and

It includes a passivation layer surrounding the light emitting part,

The first electrode is,

Comprising a bonding layer having a diameter larger than the diameter of the light emitting part

Semiconductor light emitting device.
According to paragraph 4,

The bonding layer is,

a first bonding layer below the light emitting unit;

a second bonding layer below the first bonding layer; and

A third bonding layer between the first bonding layer and the second bonding layer; comprising

Semiconductor light emitting device.
According to clause 5,

The second bonding layer is,

Having a diameter larger than the diameter of the light emitting part

Semiconductor light emitting device.
According to clause 5,

The second bonding layer is,

Comprising a protrusion protruding outward from a side of the light emitting unit

Semiconductor light emitting device.
According to clause 5,

The second bonding layer is,

having a diameter larger than the diameter of at least one of the first bonding layer or the third bonding layer.

Semiconductor light emitting device.
According to clause 5,

The second bonding layer is,

Comprising a protrusion protruding in an outward direction from a side of at least one of the first bonding layer and the third bonding layer.

Semiconductor light emitting device.
According to clause 5,

The third bonding layer is,

Comprising the material of the first bonding layer and the material of the second bonding layer

Semiconductor light emitting device.
According to clause 5,

The first bonding layer and the second bonding layer each include at least one of Sn, In, Cu, Au, Ag, Ni, Ti, W, Cr, or Pb or an alloy thereof.

Semiconductor light emitting device.
According to paragraph 4,

The first electrode is,

Containing at least one layer of an electrode layer, a magnetic layer, an ohmic layer, a reflective layer, an adhesive layer, or a barrier layer.

Semiconductor light emitting device.
According to paragraph 4,

The first electrode vertically overlaps each of the light emitting unit and the passivation layer.

Semiconductor light emitting device.
A substrate including a plurality of sub-pixels;

a plurality of first assembly wirings for each of the plurality of sub-pixels;

a plurality of second assembly wirings for each of the plurality of sub-pixels;

a partition wall having a plurality of assembly holes in each of the plurality of sub-pixels;

a plurality of semiconductor light emitting devices in each of the plurality of assembly holes; and

Includes a plurality of connection electrodes,

Each of the plurality of semiconductor light emitting devices,

light emitting part;

a first electrode including a plurality of first layers below the light emitting unit;

a second electrode on the light emitting unit; and

It includes a passivation layer surrounding the light emitting part,

The first electrode is,

It includes a bonding layer having a diameter larger than the diameter of the light emitting part,

Each of the connection electrodes is,

Connecting the first electrode and at least one assembly wiring of the first assembly wiring or the second assembly wiring

Display device.
According to clause 14,

Each of the connection electrodes is,

connected to the bonding layer

Display device.
According to clause 14,

The bonding layer is,

a first bonding layer below the light emitting unit;

a second bonding layer below the first bonding layer; and

It includes a third bonding layer between the first bonding layer and the second bonding layer,

Each of the connection electrodes is,

Connected to the side and top surfaces of the second bonding layer along the outer peripheral surface of the second bonding layer

Display device.
According to clause 16,

Each of the connection electrodes is,

Connected to each side of the first bonding layer and the third bonding layer

Display device.
According to clause 14,

The first electrode is,

It includes at least one layer of an electrode layer, a magnetic layer, an ohmic layer, a reflective layer, an adhesive layer, or a barrier layer,

Each of the connection electrodes is,

connected to the side of the at least one layer

Display device.