JP7616040B2 - LED display and its manufacturing method - Google Patents

Description

The technical field of this specification relates to LED displays and manufacturing methods thereof.

Display devices are used in a wide variety of applications, including televisions, desktop computers, notebook computers, and smartphones. Micro LED displays that use LED elements have been researched and developed. Micro LED displays are made up of tiny light-emitting elements measuring between 1 μm and 100 μm, arranged in a matrix.

In such micro LED displays, screen defects may occur due to partial light emission failure of the LED elements. For example, if there is a short-circuited light emitting element, current may concentrate in that light emitting element, causing a current shortage in other light emitting elements. In this case, it becomes difficult to make the desired light emitting element shine brightly. Patent Document 1 discloses a technology for preventing current from flowing to light emitting elements with light emission failures in a large-area light emitting device (paragraphs [0010]-[0011] of Patent Document 1). To achieve this, the entire light emitting element is covered with an insulating film 10 (paragraphs [0060] and Figure 2 of Patent Document 1).

JP 2006-286991 A

Patent Document 1 discloses that by accurately selecting defective light-emitting elements and not passing electricity through such light-emitting elements, it is possible to manufacture light-emitting devices with a high yield rate that can ensure the desired light-emitting brightness even if light-emitting elements with low light-emitting efficiency are present (paragraph [0089] of Patent Document 1).

However, in a display device, if electricity is not applied to a light-emitting section with low light-emitting efficiency, image defects such as non-emitting areas may occur. In addition, a display device has many light-emitting sections. Therefore, forming an insulating film on multiple light-emitting sections out of the many light-emitting sections makes the process complicated.

The problem that the technology of this specification aims to solve is to provide a manufacturing method for an LED display and an LED display that can suppress image defects using simple processes.

The manufacturing method of the LED display in the first aspect includes the steps of inspecting a light emitting portion of a monolithic light emitting element, mounting the light emitting element on a drive circuit board, forming a base layer and a surface layer of an electrode electrically connected to the light emitting portion, removing the surface layer of the electrode electrically connected to the defective light emitting portion to expose the base layer, and oxidizing the exposed base layer. In the mounting step , the p-type semiconductor layer of the defective light emitting portion is not electrically connected to the electrode of the drive circuit board.

In this manufacturing method for LED displays, shorted light-emitting sections and light-emitting sections that do not emit light are not connected to the drive circuit. Since light-emitting sections that are not emitting light properly are not connected to the drive circuit, image defects are suppressed in LED displays manufactured using this manufacturing method.

This specification provides a manufacturing method for an LED display that can suppress image defects using simple steps, and an LED display.

FIG. 2 is a schematic diagram of an LED display D1 according to the first embodiment. 1 is a diagram showing a layered structure of an LED display D1 according to a first embodiment. FIG. 1 is a diagram illustrating the p-electrode P1 of the micro LED element 100, the transparent substrate TS1, and the drive circuit board 200 of the LED display D1 of the first embodiment. 2 is a circuit diagram showing a schematic diagram of a drive circuit CC1 of the LED display D1 of the first embodiment. FIG. 10A to 10C are diagrams for explaining a method of processing the p-electrode P1 of the micro LED element 100 of the LED display D1 of the first embodiment.

Specific embodiments will be described below with reference to the figures, taking an LED display as an example. However, the technology of this specification is not limited to these embodiments. The layered structure and electrode structure of each layer of the LED display described below are examples. Of course, layered structures different from those in the embodiments may also be used. Furthermore, the thickness ratios of each layer in each figure are shown conceptually, and do not represent the actual thickness ratios.

(First embodiment)
1. LED Display Fig. 1 is a schematic diagram of an LED display D1 according to a first embodiment. The LED display D1 includes a micro LED element 100 and a drive circuit board 200. As shown in Fig. 1, the micro LED element 100 is a monolithic semiconductor light emitting element.

The micro LED element 100 has a plurality of pixel light-emitting portions A1. The pixel light-emitting portion A1 is a light-emitting region corresponding to one pixel. For this reason, the pixel light-emitting portions A1 are arranged in a matrix. The pixel light-emitting portion A1 has sub-pixel light-emitting portions R1, G1, and B1. The sub-pixel light-emitting portions R1, G1, and B1 are regions that emit red, green, and blue light, respectively.

The subpixel light-emitting unit R1 has a first partial light-emitting unit RC1 and a second partial light-emitting unit RC2 connected in parallel. The subpixel light-emitting unit G1 has a first partial light-emitting unit GC1 and a second partial light-emitting unit GC2 connected in parallel. The subpixel light-emitting unit B1 has a first partial light-emitting unit BC1 and a second partial light-emitting unit BC2 connected in parallel.

In this way, each subpixel light-emitting unit has two partial light-emitting units. This is because, due to redundancy, even if one partial light-emitting unit does not emit light, the remaining partial light-emitting unit will emit light, thereby avoiding poor light emission. Of course, each subpixel light-emitting unit may have two or more partial light-emitting units.

The first partial light-emitting unit RC1 is electrically connected to the p-electrode P1a. The second partial light-emitting unit RC2 is electrically connected to the p-electrode P1b. The first partial light-emitting unit GC1 is electrically connected to the p-electrode P1c. The second partial light-emitting unit GC2 is electrically connected to the p-electrode P1d. The first partial light-emitting unit BC1 is electrically connected to the p-electrode P1e. The second partial light-emitting unit BC2 is electrically connected to the p-electrode P1f. These p-electrodes may be collectively referred to as the p-electrode P1.

In this way, each subpixel light-emitting portion has a first partial light-emitting portion and a second partial light-emitting portion. The first partial light-emitting portion and the second partial light-emitting portion are adjacent regions, and different electrodes are connected to each of them. For example, if the second partial light-emitting portion has a light-emitting defect and does not emit light, the first partial light-emitting portion emits light.

The micro LED element 100 is mounted on the drive circuit board 200. The drive circuit board 200 has a drive circuit CC1. The drive circuit CC1 drives the micro LED element 100.

2. Stacked structure Fig. 2 is a diagram showing the stacked structure of the LED display D1 of the first embodiment. As shown in Fig. 2, the micro LED element 100 has a transparent substrate TS1, a semiconductor layer SM1, a p-electrode P1, an n-electrode N1, and a reflective layer RF1. The micro LED element 100 is a monolithic light emitting element made of a group III nitride semiconductor in which a plurality of light emitting portions are arranged in a matrix in one element.

The transparent substrate TS1 is, for example, sapphire, GaN, or SiC.

The semiconductor layer SM1 has an n-type contact layer 120, a first light-emitting layer 130, a first base layer 140, a second light-emitting layer 150, a second base layer 160, a third light-emitting layer 170, a cap layer 180, and a p-type contact layer 190.

The drive circuit board 200 has a drive circuit CC1. The drive circuit CC1 has transistors TrR1, TrG1, and TrB1. The transistors TrR1, TrG1, and TrB1 are selection transistors that select whether or not to pass current to the partial light-emitting portion.

The subpixel light-emitting portion R1 has an n-type contact layer 120, a first light-emitting layer 130, a first base layer 140, a second light-emitting layer 150, a second base layer 160, a third light-emitting layer 170, a cap layer 180, and a p-type contact layer 190.

The subpixel light-emitting portion G1 has an n-type contact layer 120, a first light-emitting layer 130, a first base layer 140, a second light-emitting layer 150, a second base layer 160, and a p-type contact layer 190.

The subpixel light-emitting portion B1 has an n-type contact layer 120, a first light-emitting layer 130, a first base layer 140, and a p-type contact layer 190.

The p-electrodes P1 are each provided on the transparent electrode TE1. The transparent electrode TE1 is provided on the p-type contact layer 190. The p-electrodes P1 are arranged in a matrix pattern. Therefore, one transparent electrode TE1 and one p-electrode P1 are each arranged in the first partial light-emitting section and the second partial light-emitting section.

The n-electrode N1 is formed in a rectangular ring-shaped pattern along the outer periphery of the micro LED element 100. A groove is formed by etching on the outer periphery of the micro LED element 100, reaching the n-type contact layer 120, and the n-electrode N1 is provided on the n-type contact layer 120 exposed at the bottom of the groove. There is one n-electrode N1, which is common to each pixel. Therefore, the n-electrode N1 is common to all the first partial light-emitting portions and the second partial light-emitting portions. The material of the n-electrode N1 is, for example, a laminate such as Ti/Al.

The micro LED element 100 does not have grooves to separate each pixel, and the n-electrode N1 is also common to each pixel. This makes it possible to miniaturize the element.

The n-electrode N2 is provided on the drive circuit board 200 side. The n-electrode N2 is electrically connected to the n-electrode N1 of the micro LED element 100.

The p-electrode P2 is provided on the drive circuit board 200 side. The p-electrode P2 is electrically connected to the p-electrode P1 of the micro LED element 100.

The insulating layer I1 is a layer that insulates the multiple p-electrodes P1. The insulating layer I1 also insulates the transparent electrodes TE1 of each partial light-emitting portion.

3. Electrode Structure As shown in Fig. 1, in the LED display D1 of the first embodiment, the electrodes connected to the defective light-emitting portion are not electrically connected to the drive circuit CC1.

Figure 3 is a diagram illustrating the p-electrode P1 of the micro LED element 100, the transparent substrate TS1, and the drive circuit board 200 of the LED display D1 of the first embodiment.

For the sake of explanation, it is assumed here that the first partial light-emitting unit RC1 is a light-emitting unit (first light-emitting unit) capable of emitting light satisfactorily, and the second partial light-emitting unit RC2 is a light-emitting unit (second light-emitting unit) that is defective in emitting light. For example, the brightness of the defective light-emitting unit is 20% or more lower than the brightness of the light-emitting unit that is capable of emitting light satisfactorily. As described below, the defective emitting of the second partial light-emitting unit RC2 is confirmed by an inspection process.

3-1. Electrode material The material of the underlayer P1a1 of the p-electrode P1a is the same as the material of the underlayer P1b1 of the p-electrode P1b. The material of the underlayer P1a1 of the p-electrode P1a and the underlayer P1b1 of the p-electrode P1b is, for example, Ti, Al, Ni, or Cr. Other metals or alloys may also be used. These materials are metals that are relatively easy to oxidize.

The material of the surface layer P1a2 of the p-electrode P1a is different from the material of the surface layer P1b3 of the p-electrode P1b.

The surface layer P1b3 of the p-electrode P1b is made of an oxide of the material of the underlayer P1b1 of the p-electrode P1b. The surface layer P1b3 of the p-electrode P1b is made of _a metal oxide, such as _TiO2 , _Al2O3 , NiO, _{or Cr2O3} .

3-2. Electrodes of light-emitting portion that emits light satisfactorily The p-electrode P1a is electrically connected to the electrode P2 of the drive circuit board 200, i.e., the drive circuit CC1. The p-electrode P1a has an underlayer P1a1 and a surface layer P1a2. The underlayer P1a1 and the surface layer P1a2 are conductive. The surface layer P1a2 is, for example, a metal such as Ti, Al, Ag, or Au, or an alloy.

3-3. Electrodes of a light-emitting portion with poor light emission The p-electrode P1b is not electrically connected to the electrode P2 of the drive circuit board 200, i.e., the drive circuit CC1. The p-electrode P1b has an underlayer P1b1 and a surface layer P1b3. The underlayer P1b1 is conductive. The underlayer P1b1 is, for example, a metal or alloy such as Ti, Al, Ni, or Cr. The surface layer P1b3 is insulating. The surface layer P1b3 is an oxide layer formed by oxidizing the underlayer P1b1.

3-4. Positional relationship of electrode surfaces The distance H0 from the surface TS1a of the transparent substrate TS1 to the surface P1as of the p-electrode P1a is longer than the distance H2 from the surface TS1a of the transparent substrate TS1 to the surface P1bs of the p-electrode P1b. Here, the surface P1as is the surface of the p-electrode P1a that is closest to the surface 200a of the drive circuit substrate 200. The surface P1bs is the surface of the p-electrode P1b that is closest to the surface 200a of the drive circuit substrate 200.

In addition, the distance H1 from the surface TS1a of the transparent substrate TS1 to the interface P1am between the underlayer P1a1 and the surface layer P1a2 of the p-electrode P1a is longer than the distance H2 from the surface TS1a of the transparent substrate TS1 to the surface P1bs of the p-electrode P1b.

The distance J2 from the plate surface 200a of the drive circuit board 200 to the surface P1bs of the p-electrode P1b is longer than the distance J0 from the plate surface 200a of the drive circuit board 200 to the surface P1as of the p-electrode P1a.

In addition, the distance J1 from the plate surface 200a of the drive circuit board 200 to the interface P1am between the underlayer P1a1 and the surface layer P1a2 of the p-electrode P1a is shorter than the distance J2 from the plate surface 200a of the drive circuit board 200 to the surface P1bs of the p-electrode P1b.

As such, since the surface layer P1b3 of the p-electrode P1b is made of an insulating material, the p-electrode P1b is not electrically connected to the drive circuit CC1 of the drive circuit board 200.

In addition, the surface P1as of the p-electrode P1a is joined to the electrode P2 of the drive circuit board 200 via a joining layer such as solder. Therefore, it is possible to identify the surface P1as of the p-electrode P1a.

On the other hand, the surface P1bs of the p-electrode P1b is not joined to solder or the like. The surface P1bs of the p-electrode P1b faces a gas layer such as air. This is because there is a step between the p-electrodes P1a and P1b, as shown in FIG. 3.

4. Circuit Diagram 4-1. Circuit Configuration Fig. 4 is a circuit diagram showing a schematic diagram of a driving circuit CC1 of the LED display D1 of the first embodiment. As shown in Fig. 4, the driving circuit CC1 has a scanning line circuit 210, a PWM circuit 220, a scanning line 230, a data line 240, and transistors TrR1, TrR2, TrG1, TrG2, TrB1, and TrB2.

The scanning line circuit 210 and the PWM circuit 220 are realized as LSI elements and mounted on the drive circuit board 200.

The scanning line circuit 210 is a circuit that sequentially selects and energizes one of the scanning lines 230 provided for each row of the LED display D1. The scanning line circuit 210 sequentially selects and scans the rows to be illuminated of the subpixel light emitting portions R1, G1, and B1 one by one.

The PWM circuit 220 is provided for each column of the LED display D1. The PWM circuit 220 is connected to the data line 240. The PWM circuit 220 is a circuit that pulse modulates the current flowing through the partial light-emitting unit (RC1, etc.), and is a circuit that controls the brightness of the partial light-emitting unit by the duty ratio. By using PWM control, the brightness can be controlled without causing a deviation in the emission wavelength of the partial light-emitting unit. In this way, the PWM circuit 220 is provided for each column of the sub-pixel light-emitting units R1, G1, and B1, and controls the duty ratio by pulse modulating the current flowing through the sub-pixel light-emitting units R1, G1, and B1.

A scanning line 230 is provided for each row of the LED display D1. The scanning line 230 is connected in parallel to the gates of the transistors TrR1, TrG1, and TrB1 of the corresponding row.

Data lines 240 are provided for each column of LED display D1. Data lines 240 are connected in parallel to the drains of transistors TrR1, TrG1, and TrB1 in the corresponding column.

Transistors TrR1, TrR2, TrG1, TrG2, TrB1, and TrB2 are provided for each partial light-emitting section (RC1, RC2, GC1, GC2, BC1, and BC2). The gates of transistors TrR1, TrG1, TrG2, TrB1, and TrB2 are connected to the scanning line 230, the drains are connected to the data line 240, and the sources are connected to the anodes (p-electrodes P1) of the partial light-emitting sections (RC1, etc.). The on/off state of transistors TrR1, TrG1, TrG2, TrB1, and TrB2 is controlled by applying a voltage to the gates. When in the on state, the line is conductive and current flows to the partial light-emitting section (RC1, etc.), and when in the off state, the line is cut off and no current flows to the partial light-emitting section (RC1, etc.).

Here, the transistor TrR2 is not electrically connected to the defective second partial light-emitting unit RC2. The defective second partial light-emitting unit RC2 is in an open state. In other words, the source of the transistor TrR2 is not connected to the anode (p electrode P1) of the second partial light-emitting unit RC2. The gate of the transistor TrR2 is connected to the scanning line 230, and the drain is connected to the data line 240.

The subpixel light-emitting unit R1 has a first partial light-emitting unit RC1, a second partial light-emitting unit RC2, and transistors TrR1 and TrR2. The subpixel light-emitting unit G1 has a first partial light-emitting unit GC1, a second partial light-emitting unit GC2, and transistors TrG1 and TrG2. The subpixel light-emitting unit B1 has a first partial light-emitting unit BC1, a second partial light-emitting unit BC2, and transistors TrB1 and TrB2.

The transistors TrR1, TrG1, TrG2, TrB1, and TrB2 in the row selected by the scanning line circuit 210 are turned on, allowing current to flow to the subpixel light-emitting portions R1, G1, and B1. The transistors TrR1, TrG1, TrG2, TrB1, and TrB2 in the row not selected by the scanning line circuit 210 are turned off, allowing no current to flow to the subpixel light-emitting portions R1, G1, and B1.

On the other hand, no current flows through transistor TrR2, regardless of the operation of the scanning line circuit 210.

4-2. Circuit operation First, the scanning line circuit 210 selects one of the scanning lines 230. At this time, a voltage is applied to the gate of the transistor connected to the selected scanning line 230. At this stage, the partial light emitting portion connected to the source of the transistor does not emit light yet.

When the scanning line circuit 210 is selected, the PWM circuit 220 generates a pulse-modulated current on the data line 240. This current is input to the drain of the transistor. This causes a current to flow through the two partial light-emitting sections connected to the source of the transistor, causing these partial light-emitting sections to emit light.

Since the p-electrode P1b of the defective second partial light-emitting part RC2 is not electrically connected, no current flows through the second partial light-emitting part RC2 at all times.

5. LED Display Manufacturing Method 5-1. Semiconductor Layer Forming Step Manufacturing the micro LED element 100. A semiconductor layer SM1 is sequentially formed on a transparent substrate TS1.

5-2. Electrode formation process A transparent electrode TE1 is formed on the semiconductor layer SM1. A p-electrode P1 is formed on the transparent electrode TE1. In this manner, a base layer and a surface layer of the p-electrode P1 that is electrically connected to the light-emitting section are formed. A recess is formed that reaches from the p-type contact layer 190 to the n-type contact layer 120, and an n-electrode N1 is formed in the recess.

5-3. Inspection process The light-emitting parts of the micro LED element 100 are inspected. The presence or absence of partial light-emitting parts with light emission defects is inspected by passing electricity through each light-emitting part. Then, the position of the partial light-emitting part with light emission defects is identified. Through the inspection, for example, it is detected that the second partial light-emitting part RC2 has a light emission defect.

5-4. Underlying Layer Exposure Step Fig. 5 is a diagram for explaining a method for processing the p-electrode P1 of the micro LED element 100 of the LED display D1 of the first embodiment.

The surface layer P1b2 of the p-electrode P1b of the second partial light-emitting portion RC2 is trimmed by laser trimming, and the underlayer P1b1 is trimmed partway through. This exposes the underlayer P1b1 of the p-electrode P1b. In this way, in the process of exposing the underlayer, the surface layer P1b2 electrically connected to the light-emitting portion with poor light emission is removed, and a part of the underlayer P1b1 electrically connected to the light-emitting portion with poor light emission is removed.

5-5. Underlayer oxidation step Next, the exposed surface of the underlayer P1b1 is oxidized. A mask is applied to the area other than the exposed underlayer P1b1, and only the underlayer P1b1 is oxidized. As a result, the surface of the underlayer P1b1 is oxidized to form a surface layer P1b3. The surface layer P1b3 is an oxide layer obtained by oxidizing the underlayer P1b1.

5-6. Mounting process The micro LED element 100 is mounted on the drive circuit board 200. In this mounting process, the p-type semiconductor layer of the light-emitting portion that can emit light is electrically connected to the electrode P2 of the drive circuit board 200, and the p-type semiconductor layer of the light-emitting portion that is not capable of emitting light is not electrically connected to the electrode P2 of the drive circuit board 200. The bonding is performed by reflow using solder or the like. Other bonding methods may also be used.

6. Effects of the First Embodiment In the manufacturing method of the LED display D1 of the first embodiment, the defective light-emitting portion is not electrically connected to the drive circuit CC1. For this purpose, the surface layer of the p-electrode P1 once formed on the defective light-emitting portion is removed, and the base layer is exposed and oxidized. This oxidized layer is insulating.

The distance J2 from the plate surface 200a of the circuit drive board 200 to the p-electrode P1b of the second partial light-emitting unit RC2 is longer than the distance J0 from the plate surface 200a of the circuit drive board 200 to the p-electrode P1a of the first partial light-emitting unit RC1. For this reason, when mounting the micro LED element 100, the p-electrode P1b of the second partial light-emitting unit RC2 may not be solder-joined. Regardless of the presence or absence of solder-joining, the p-electrode P1b is not electrically connected to the drive circuit CC1.

In this way, the p-electrode P1b of the second partial light-emitting portion RC2 has an air layer and an oxide layer (surface layer P1b3) between it and the electrode P2 of the circuit driving board 200. Therefore, the partial light-emitting portion (RC2) that is not emitting light properly is not electrically connected to the driving circuit CC1.

In addition, since the PWM circuit 220 is provided for each column, the number of circuits can be reduced compared to when a PWM circuit 220 is provided for each partial light-emitting section. In other words, the LED display D1 can be miniaturized.

In addition, although part of the electrode is trimmed, there is no risk of damaging the semiconductor layer.

7. Modification 7-1. Micro LED element preparation step The micro LED element 100 may be purchased. In this manner, the micro LED element 100 may be prepared.

Second Embodiment
A second embodiment will be described.

1. Micro LED Element The micro LED element of the second embodiment is obtained by removing the electrodes of the defective light-emitting portions from the micro LED element 100 of the first embodiment. In this micro LED element, no electrodes are provided on the defective light-emitting portions.

2. LED Display Manufacturing Method 2-1. Semiconductor Layer Forming Step A semiconductor layer SM1 is sequentially formed on a transparent substrate TS1.

2-2. Inspection process In the inspection process, the light emitting portion of the semiconductor layer is inspected by photoluminescence. The light emitting portion that will be the micro LED element of the second embodiment is caused to emit light, and the emitted light image is acquired by a camera or the like. Then, the light emitting region and the non-light emitting region are identified from the acquired light emitting image. This identifies the position of the partial light emitting portion that has a light emission defect.

2-3. Electrode Formation Process An electrode is formed on the light-emitting portion. An electrode is formed on the light-emitting portion that can emit light well, without forming an electrode on the light-emitting portion that is not emitting light well. For example, a mask is formed on the light-emitting portion that is not emitting light well, and an electrode is formed on the other light-emitting portions. The mask is then removed from the light-emitting portion that is not emitting light well. This completes the manufacture of a micro LED element.

The micro LED elements are mounted on the drive circuit board 200. In this manner, the LED display of the second embodiment is manufactured.

3. Advantages of the Second Embodiment In the manufacturing method of the LED display according to the second embodiment, it is possible to identify a defective light-emitting portion before forming the electrodes. Therefore, it is not necessary to remove the electrodes, and the semiconductor layer is less likely to be damaged.

(Additional Note)
The method for manufacturing an LED display according to the first aspect includes a step of inspecting a light-emitting portion of a monolithic light-emitting element, and a step of mounting the light-emitting element on a drive circuit board, in which the p-type semiconductor layer of the light-emitting portion having a light-emitting defect is not electrically connected to an electrode of the drive circuit board.

The manufacturing method of the LED display in the second aspect includes a step of forming a base layer and a surface layer of an electrode electrically connected to a light-emitting section, a step of removing the surface layer of the electrode electrically connected to the light-emitting section having poor light emission to expose the base layer, and a step of oxidizing the exposed base layer.

In the third aspect of the LED display manufacturing method, the step of exposing the base layer involves removing a portion of the base layer that is electrically connected to the defective light-emitting portion.

The manufacturing method of the LED display in the fourth aspect includes a step of forming an electrode on the light-emitting portion. In the step of inspecting the light-emitting portion, the light-emitting portion of the light-emitting element is made to emit light by photoluminescence to obtain a light-emitting image, and the position of the light-emitting portion that is defective in light emission is identified from the light-emitting image. In the step of forming the electrode, an electrode is formed on the light-emitting portion that is capable of emitting light, without forming an electrode on the light-emitting portion that is defective in light emission.

The LED display in the fifth aspect has a light-emitting element having a substrate, a semiconductor layer, an n-electrode, and a p-electrode, and a drive circuit board on which the light-emitting element is mounted. The semiconductor layer has a first light-emitting section capable of emitting light and a second light-emitting section that is poor at emitting light. The first light-emitting section is electrically connected to the first p-electrode. The second light-emitting section is electrically connected to the second p-electrode. The drive circuit board has a drive circuit. The second p-electrode is not electrically connected to the drive circuit. The distance from the plate surface of the drive circuit board to the second p-electrode is longer than the distance from the plate surface of the drive circuit board to the first p-electrode.

In the sixth embodiment of the LED display, the surface layer of the second p-electrode is a metal oxide layer.

D1...LED display 100...micro LED element 120...n-type contact layer 130...first light-emitting layer 140...first base layer 150...second light-emitting layer 160...second base layer 170...third light-emitting layer 180...cap layer 190...p-type contact layers P1a, P1b...p-electrode P1a1...base layer P1a2...surface layer P1b1...base layer P1b3...surface layer N1...n-electrode

Claims (3)

inspecting a light emitting portion of a monolithic light emitting device;
mounting the light emitting device on a driving circuit board;
forming a base layer and a surface layer of an electrode electrically connected to the light emitting portion;
removing the surface layer of the electrode electrically connected to the defective light emitting portion to expose the base layer;
oxidizing the exposed underlayer;
having
In the mounting step,
A method for manufacturing an LED display, comprising: not electrically connecting a p-type semiconductor layer of the light-emitting portion having a light emission defect to an electrode of the drive circuit board. 2. The method for manufacturing an LED display according to claim 1 ,
In the step of exposing the underlayer,
A method for manufacturing an LED display, comprising: removing a part of the underlayer that is electrically connected to the defective light-emitting portion. a light emitting device having a substrate, a semiconductor layer, an n-electrode, and a p-electrode;
a drive circuit board on which the light emitting device is mounted;
In an LED display having
The semiconductor layer is
a first light-emitting section capable of emitting light and a second light-emitting section having a light-emitting defect;
The first light emitting unit is
electrically connected to the first p-electrode,
The second light emitting unit is
electrically connected to the second p-electrode,
The drive circuit board includes:
A drive circuit is provided.
The second p-electrode is
is not electrically connected to the drive circuit;
The distance from the surface of the drive circuit board to the second p-electrode is
longer than the distance from the surface of the drive circuit board to the first p-electrode,
The surface layer of the second p-electrode is a metal oxide layer.
An LED display including:

Images