KR20230064582A - Device for repairing a semiconductor light emitting device for a pixel and a repair method using the same - Google Patents

Abstract

A method of repairing a semiconductor light emitting device for a pixel according to an embodiment includes disposing a pressure head having pins on an optical system; moving the pressure head from a first height to a second height; and observing an image of the pin from the first height to the second height with the optical system, wherein the first image of the pin at the first height represents a first area, and at the second height The second image of the pin may indicate the first area and the second area, and tilting the pressing head so that a center of the first area and a center of the second area coincide.

Description

Repair device for a semiconductor light emitting device for a pixel and a repair method using the same {Device for repairing a semiconductor light emitting device for a pixel and a repair method using the same}

Embodiments relate to a repair device for a semiconductor light emitting device for a pixel and a method for a repair method using the same.

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

A micro-LED display is a display using a micro-LED, which is a semiconductor light emitting device having a diameter or cross-sectional area of 100 μm or less, as a display device.

Micro-LED display has excellent performance in many characteristics such as contrast ratio, response speed, color reproducibility, viewing angle, brightness, resolution, lifespan, luminous efficiency or luminance because it uses micro-LED, which is a semiconductor light emitting device, as a display element.

In particular, the micro-LED display has the advantage of being free to adjust the size or resolution as screens can be separated and combined in a modular manner, and can implement a flexible display.

However, in the process of assembling the micro-LED into the display device, a repair process is required for the non-assembled or defective micro-LED.

In addition, the number of micro-LEDs subject to repair may be tens of thousands or more. Accordingly, there is a need for a method of increasing the transfer rate of the micro-LED through the repair process and increasing the luminous efficiency of the display device.

Embodiments are aimed at solving the foregoing and other problems.

Another object of the embodiment is to increase the transfer rate in assembling a semiconductor light emitting device.

In addition, another object of the embodiment is to increase the removal rate when removing the semiconductor light emitting device.

In addition, another object of the embodiment is to precisely set the verticality of the pin attached to the pressing head.

Further, another object of the embodiments is to reduce the replacement frequency of pins attached to the pressure head.

In addition, another object of the embodiment is to determine the locations of randomly arranged semiconductor light emitting devices.

In addition, another object of the embodiment is to determine z-axis positions of semiconductor light emitting devices having different z-axis positions.

In addition, another object of the embodiment is to improve process yield by applying pressurization conditions suitable for semiconductor light emitting devices having different z-axis positions.

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

A method of repairing a semiconductor light emitting device for a pixel according to an embodiment includes disposing a pressure head having pins on an optical system; moving the pressure head from a first height to a second height; and observing an image of the pin from the first height to the second height with the optical system, wherein the first image of the pin at the first height represents a first area, and at the second height The second image of the pin may indicate a second area, and tilting the pressure head so that a center of the first area and a center of the second area coincide.

Further, in an embodiment, the first height may be a height such that the depth of focus of the optical system is located at the center of the pin, and the second height may be a height such that the depth of focus of the optical system is located at the peak of the pin.

In addition, the embodiment may further include pressing the semiconductor light emitting device with the pin after tilting the pressing head.

Also, in an embodiment, the fin may be in a vertical relationship with the semiconductor light emitting device.

Also, in an embodiment, the first area and the second area may be concentric circles.

Further, in the embodiment, the pressure head and the pin include a plurality, and the step of tilting the pressure head may tilt at least one of the plurality of pressure heads.

Also, a method of repairing a semiconductor light emitting device for a pixel according to another embodiment includes arranging an optical system at a third height on a plurality of semiconductor light emitting devices attached to a film;

obtaining a clear image of at least one of the plurality of semiconductor light emitting devices with the optical system; obtaining data on a z-axis height of at least one of the plurality of semiconductor light emitting devices corresponding to the clear image; moving the optical system by a predetermined height in the z-axis direction; and acquiring a clear image of at least one other of the plurality of semiconductor light emitting devices with the optical system.

In addition, in the embodiment, the step of moving the optical system by a predetermined height in the z-axis direction is repeated until the optical system is positioned at a fourth height, and the difference between the third height and the fourth height is It may be more than twice the depth of focus range.

Also, in an embodiment, the plurality of semiconductor light emitting devices may be located within a depth of focus range of the optical system.

In addition, the embodiment may further include changing pressurization conditions to correspond to the z-axis height after obtaining data on the z-axis height of at least one of the plurality of semiconductors.

The method for repairing a semiconductor light emitting device for a pixel according to the embodiment has a technical effect of increasing an assembly rate when assembling a chip.

In addition, the method for repairing a semiconductor light emitting device for a pixel according to the embodiment has a technical effect of increasing a removal rate during chip removal.

In addition, the embodiment has a technical effect of improving repair accuracy of the subminiature semiconductor light emitting device even without using a high-magnification optical system.

In addition, the embodiment has a technical effect of preventing bending of the pins mounted on the pressure head and reducing the replacement frequency of the pins.

In addition, the embodiment has a technical effect of improving the removal rate during chip removal by increasing the adhesion rate with the semiconductor light emitting device by applying an adhesive material to the tip of the pin.

In addition, the embodiment has a technical effect of precisely controlling the verticality of the pin even if the optical system is located at the bottom, side, or top of the pin.

In addition, the method for repairing a semiconductor light emitting device for a pixel according to the embodiment has a technical effect of being able to locate randomly arranged semiconductor light emitting devices.

In addition, the embodiment has a technical effect of determining the z-axis positions of semiconductor light emitting elements having different z-axis positions.

In addition, the embodiment has a technical effect of improving the process yield by changing the pressurization conditions according to the z-axis position of the semiconductor light emitting devices.

A further 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 can be clearly understood by those skilled in the art, it should be understood that the detailed description and specific embodiments, such as preferred embodiments, are given by way of example only.

1 illustrates a living room of a house in which a display device using a semiconductor light emitting device for a pixel according to an exemplary embodiment is disposed.
2 is a schematic block diagram of a display device using a semiconductor light emitting device for a pixel according to an exemplary embodiment.
3 is a circuit diagram illustrating an example of a pixel of FIG. 2 .
FIG. 4 is an enlarged view of a first panel area in the display device of FIG. 1 .
FIG. 5 is an enlarged view of area A2 of FIG. 4 .
6 is a diagram illustrating an example in which a semiconductor light emitting device according to an embodiment is assembled to a substrate by a self-assembly method.
7 is a conceptual diagram of a repair device for a semiconductor light emitting device for a pixel according to the first embodiment.
8 is a conceptual diagram of a repair device for a semiconductor light emitting device for a pixel and a method using the same according to the first embodiment.
9 is a diagram of a method using a repair device for a semiconductor light emitting device for a pixel according to the first embodiment.
10 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to the first embodiment.
11 is a conceptual diagram illustrating a repair method of a semiconductor light emitting device for a pixel according to the first embodiment.
12 is a conceptual diagram illustrating a repair method of a semiconductor light emitting device for a pixel according to the first embodiment.
13 is a conceptual diagram illustrating a repair method of a semiconductor light emitting device for a pixel according to a second embodiment.
14 is a conceptual diagram illustrating a repair method of a semiconductor light emitting device for a pixel according to a third embodiment.
15 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to a fourth embodiment.
16 is a conceptual diagram illustrating a repair method of a semiconductor light emitting device for a pixel according to a fourth embodiment.
17 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to a fourth embodiment.
18 is a flowchart of a repair method of a semiconductor light emitting device for a pixel according to a fourth embodiment.

Hereinafter, the embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings, but the same or similar components are given the same reference numerals regardless of reference numerals, and redundant description thereof will be omitted. The suffixes 'module' and 'unit' for the components used in the following description are given or used interchangeably in consideration of ease of writing the specification, and do not themselves have a meaning or role that is distinct from each other. In addition, the accompanying drawings are for easy understanding of the embodiments disclosed in this specification, and the technical idea disclosed in this specification is not limited by the accompanying drawings. Also, when an element such as a layer, region or substrate is referred to as being 'on' another element, this includes being directly on the other element or other intervening elements may be present therebetween. do.

The display device described in this specification includes TV, Shinage, mobile terminal such as mobile phone or smart phone, computer display such as laptop or desktop, automobile head-up display (HUD), display backlight unit, A display for VR, AR or mixed reality (MR), a light source, and the like may be included. However, the configuration according to the embodiment described in this specification can be applied to a device capable of displaying even a new product type to be developed in the future.

Hereinafter, a display device including a semiconductor light emitting device according to an exemplary embodiment will be described.

1 illustrates a living room of a house in which a display device according to an exemplary embodiment is disposed.

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

The display device 100 according to the embodiment may include a flexible display fabricated on a thin and flexible substrate. A flexible display can be bent or rolled like paper while maintaining characteristics of a conventional flat panel display.

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

FIG. 2 is a block diagram schematically illustrating a display device according to an exemplary embodiment, and FIG. 3 is a circuit diagram illustrating an example of a 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 driving unit 30 and a power supply circuit 50 .

The display device 100 according to the embodiment may drive a light emitting element 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 controller 22 .

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

The display panel may include a display area DA. The display area DA is an area where the pixels PX are formed to display an image. The display panel may include a non-display area NDA. The non-display area DNA may be an area excluding the display area DA.

As an example, the display area DA and the non-display area NDA may be defined on the same surface. For example, the non-display area DNA may surround the display area DA on the same surface as the display area DA, but is not limited thereto.

As another example, although not shown in the figure, the display area DA and the non-display area NDA may be defined on different surfaces. For example, the display area DA may be defined on the upper surface of the substrate, and the non-display area NDA may be defined on the lower surface of the substrate. For example, the non-display area NDA may be defined on the entire area or a partial area of the lower surface of the substrate.

Meanwhile, although it is shown as being divided into a display area DA and a non-display area NDA in the drawing, the display area DA and the non-display area NDA may not be divided. That is, only the display area DA may exist on the upper surface of the substrate, and the non-display area NDA may not exist. In other words, the entire area of the upper surface of the substrate is the display area DA where the image is displayed, and the bezel area, which is the non-display area NDA, may not exist.

The display panel 10 includes data lines (D1 to Dm, where m is an integer greater than or equal to 2), scan lines (S1 to Sn, where n is an integer greater than or equal to 2) crossing the data lines (D1 to Dm), and a high potential voltage. Connected to the high potential voltage line (VDDL) to which (VDD) is supplied, the low potential voltage line (VSSL) to which the low potential voltage (VSS) is supplied, and the data lines (D1 to Dm) and scan lines (S1 to Sn). may include the pixels PX.

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 light of a first color of a first main wavelength, the second sub-pixel PX2 emits light of a second color of a second main wavelength, and the third sub-pixel PX3 emits light of a second color. A third color light having 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. In addition, in FIG. 2, it is illustrated that each of the pixels PX includes three sub-pixels, but is not limited thereto. That is, each of the pixels 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 a high voltage signal. It can be connected to the upper voltage line (VDDL). As shown in FIG. 3 , the first sub-pixel PX1 may include light emitting elements LD, a plurality of transistors for supplying current to the light emitting elements 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. may be

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 is not limited thereto.

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.

The plurality of transistors may include a driving transistor DT supplying current to the light emitting elements LD and a scan transistor ST supplying a data voltage to a gate electrode of the driving transistor DT, as shown in FIG. 3 . The driving transistor DT includes 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 the high potential voltage VDD is applied, and first elements of the light emitting elements LD. It may include a drain electrode connected to the electrodes. 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 data lines Dj, j an integer that satisfies 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 a difference between the gate voltage and the source voltage of the driving transistor DT.

The driving transistor DT and the scan transistor ST may be formed of thin film transistors. In addition, in FIG. 3, the driving transistor DT and the scan transistor ST have been mainly described as being formed of P-type MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), but the present invention is not limited thereto. The driving transistor DT and the scan transistor ST may be formed of N-type MOSFETs. In this case, 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 ( 2T1C (2 Transistor - 1 capacitor) having Cst) is illustrated, but 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 may be expressed with substantially the same circuit diagram as the first sub-pixel PX1 , a detailed description thereof will be omitted.

The driving circuit 20 outputs signals and voltages for driving the display panel 10 . To this end, 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 a source control signal DCS from the timing controller 22 . The data driver 21 converts the 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 controller 22 receives digital video data DATA and timing signals from the host system. The host system may be an application processor of a smart phone or tablet PC, a monitor, a system on chip of a TV, and the like.

The timing controller 22 generates control signals for controlling operation timings 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) instead of 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 controller 22 may be mounted on a circuit board. there is.

The scan driver 30 receives the 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 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 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 the voltages 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 generate the display panel 10. can be supplied to the high potential voltage line (VDDL) and the low potential voltage line (VSSL). Also, the power supply circuit 50 may generate and supply driving voltages for driving the driving circuit 20 and the scan driving unit 30 from the main power.

4 is an enlarged view of a 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 ).

Next, FIG. 5 is a cross-sectional view taken along line B1-B2 of region A2 of FIG. 4 .

Referring to FIG. 5 , the display device 100 of the embodiment includes a substrate 200, assembled wires 201 and 202, a first insulating layer 211a, a second insulating layer 211b, and a third insulating layer 206. And it may include a plurality of light emitting devices (150).

The assembly line may include a first assembly line 201 and a second assembly line 202 spaced apart from each other. The first assembling wire 201 and the second assembling wire 202 may be provided to generate dielectrophoretic force for assembling the light emitting device 150 . In addition, the first assembly line 201 and the second assembly line 202 may be electrically connected to the electrode of the light emitting device to function as electrodes of a display panel.

The assembled wires 201 and 202 may be formed of light-transmitting electrodes (ITO) or may include a metal material having excellent electrical conductivity. For example, the assembled wires 201 and 202 may be titanium (Ti), chromium (Cr), nickel (Ni), aluminum (Al), platinum (Pt), gold (Au), tungsten (W), molybdenum (Mo) ) It may be formed of at least one or an alloy thereof.

A first insulating layer 211a may be disposed between the first assembly wire 201 and the second assembly wire 202 , and a first insulating layer 211a may be disposed on the first assembly wire 201 and the second assembly wire 202 . 2 insulating layers 211b may be disposed. The first insulating layer 211a and the second insulating layer 211b may be an oxide film or a nitride film, but are not limited thereto.

The light emitting device 150 may include, but is not limited to, a red light emitting device 150, a green light emitting device 150G, and a blue light emitting device 150B0 to form a sub-pixel, respectively. It is also possible to implement red and green colors by providing a green phosphor or the like.

The substrate 200 may be formed of glass or polyimide. In addition, the substrate 200 may include a flexible material such as polyethylene naphthalate (PEN) or polyethylene terephthalate (PET). In addition, the substrate 200 may be a light-transmitting material, but is not limited thereto.

The third insulating layer 206 may include an insulating and flexible material such as polyimide, PEN, PET, or the like, and may be integrally formed with the substrate 200 to form a single substrate.

The third insulating layer 206 may be a conductive adhesive layer having adhesiveness and conductivity, and the conductive adhesive layer may be flexible and thus enable a flexible function of the display device. For example, the third insulating layer 206 may be an anisotropy 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 third insulating layer 206 may include an assembly hole 203 into which the light emitting device 150 is inserted (see FIG. 6 ). Accordingly, during self-assembly, the light emitting device 150 can be easily inserted into the assembly hole 203 of the third insulating layer 206 . The assembly hole 203 may be called an insertion hole, a fixing hole, an alignment hole, or the like.

The distance between the assembly lines 201 and 202 is smaller than the width of the light emitting element 150 and the width of the assembly hole 203, so that the assembly position of the light emitting element 150 using an electric field can be more precisely fixed.

A third insulating layer 206 is formed on the assembly wires 201 and 202 to protect the assembly wires 201 and 202 from the fluid 1200 and prevent leakage of current flowing through the assembly wires 201 and 202. can The third insulating layer 206 may be formed of a single layer or multiple layers of an inorganic insulator such as silica or alumina or an organic insulator.

In addition, the third insulating layer 206 may include an insulating and flexible material such as polyimide, PEN, PET, or the like, and may be integrally formed with the substrate 200 to form a single substrate.

The third insulating layer 206 may be an adhesive insulating layer or a conductive adhesive layer having conductivity. The third insulating layer 206 is ductile and can enable a flexible function of the display device.

The third insulating layer 206 has a barrier rib, and an assembly hole 203 may be formed by the barrier rib. For example, when the substrate 200 is formed, a portion of the third insulating layer 206 is removed, so that each of the light emitting devices 150 may be assembled into the assembly hole 203 of the third insulating layer 206 .

An assembly hole 203 to which the light emitting devices 150 are coupled is formed in the substrate 200 , and a surface on which the assembly hole 203 is formed may contact the fluid 1200 . The assembly hole 203 may guide an accurate assembly position of the light emitting device 150 .

Meanwhile, the assembly hole 203 may have a shape and size corresponding to the shape of the light emitting element 150 to be assembled at the corresponding position. Accordingly, it is possible to prevent assembly of another light emitting element or a plurality of light emitting elements into the assembly hole 203 .

6 is a view showing an example in which a light emitting device according to an embodiment is assembled to a substrate by a self-assembly method, and the self-assembly method of the light emitting device will be described with reference to the drawings.

The substrate 200 may be a panel substrate of a display device. In the following description, the substrate 200 will be described as a panel substrate of a display device, but the embodiment is not limited thereto.

Referring to FIG. 6 , a plurality of light emitting devices 150 may be put into a chamber 1300 filled with a fluid 1200 . The fluid 1200 may be water such as ultrapure water, but is not limited thereto. A chamber may also be called a water bath, container, vessel, or the like.

After that, the substrate 200 may be disposed on the chamber 1300 . Depending on the embodiment, the substrate 200 may be introduced into the chamber 1300 .

As shown in FIG. 5 , a pair of assembly wires 201 and 202 corresponding to each of the light emitting devices 150 to be assembled may be disposed on the substrate 200 .

Referring to FIG. 6 , after the substrate 200 is disposed, an assembly device 1100 including a magnetic material may move along the substrate 200 . As the magnetic material, for example, a magnet or an electromagnet may be used. The assembly device 1100 may move while in contact with the substrate 200 in order to maximize the area of the magnetic field into the fluid 1200 . Depending on the embodiment, the assembly device 1100 may include a plurality of magnetic bodies or may include a magnetic body having a size corresponding to that of the substrate 200 . In this case, the moving distance of the assembling device 1100 may be limited within a predetermined range.

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

While moving toward the assembly device 1100 , the light emitting device 150 may enter the assembly hole 203 by a dielectrophoretic force (DEP force) and come into contact with the substrate 200 .

In detail, the assembled wires 201 and 202 form an electric field by an externally supplied power, and dielectrophoretic force can be formed between the assembled wires 201 and 202 by the electric field. The light emitting element 150 can be fixed to the assembly hole 203 on the substrate 200 by this dielectrophoretic force.

The light emitting element 150 in contact with the substrate 200 may be prevented from being separated by the movement of the assembly device 1100 by the electric field applied by the assembly wires 201 and 202 formed on the substrate 200 . . According to the embodiment, since the time required to assemble each of the light emitting devices 150 to the substrate 200 can be drastically reduced by the above-described self-assembly method using the electromagnetic field, a large-area high-pixel display can be made more quickly and can be implemented economically.

At this time, a predetermined solder layer (not shown) may be formed between the assembled electrode and the light emitting device 150 assembled on the assembly hole 203 of the substrate 200 to improve the bonding strength of the light emitting device 150 .

Next, a molding layer (not shown) may be formed in the assembly hole 203 of the substrate 200 . The molding layer may be a light-transmissive resin or a resin containing a reflective material or a scattering material.

7 is a cross-sectional view of a repair device for a semiconductor light emitting device for a pixel according to the first embodiment. Referring to FIG. 7 , a pressure head 120 may be mounted on a stage 125 . The pressure head 120 may be provided singly or in plurality. For example, the pressure head 120 may include a first pressure head 121, a second pressure head 122, and a third pressure head 123, and may include a larger number of pressure heads, but It is not limited to this.

The pressure head 120 and the stage 125 may be connected by a tilt unit 126 . In addition, a predetermined pin 130 may be connected below the pressure head 120 . The pin 130 may include a first pin 131 , a second pin 132 and a third pin 133 .

The stage 125 may be connected to the first pressing head 121 and the first tilt unit 127, may be connected to the second pressing head 122 and the second tilt unit 128, and may be connected to the third pressing head 123 and the third tilt unit 129 may be connected.

In addition, the first pressure head 121 is connected to the first pin 131, the second pressure head 122 is connected to the second pin 132, and the third pressure head 123 is connected to the third pin ( 133) can be linked.

The first tilt unit 127, the second tilt unit 128, and the third tilt unit 129 may rotate at different angles. The first pressing head 121, the second pressing head 122 and the third pressing head 123 are formed by the first tilt unit 127, the second tilt unit 128 and the third tilt unit 129 Each can be tilted.

The pin 130 may be provided to correspond to each of the pressure heads 120 . The first pin 131 may be connected under the first pressure head 121, the second pin 132 may be connected under the second pressure head 122, and the third pin 133 may be connected below the third pressure head 123 . The pin 130 may be formed of metal, but is not limited thereto. The peak of the pin 130 may be formed in a flat shape.

The repair device for a semiconductor light emitting device for a pixel according to the first embodiment may be used when reassembling a semiconductor light emitting device in a display panel or removing a defective chip. The pin 130 may be used to remove a semiconductor light emitting device from a film and transfer it to an assembly hole when chips are not assembled in a display panel, or to remove defective chips when assembled.

8 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to the first embodiment.

Referring to FIG. 8 , a pin 130 may be mounted under the pressure head 120 . The optical system 140 is positioned below the pin to observe the pin 130 . At this time, the optical system 140 is set vertically with the stage (see FIG. 11) using a sensor, and the pressure head 120 may also be set vertically with the stage.

In the process of repairing the semiconductor light emitting device, if the pin 130 is not perpendicular to the stage and is in an inclined state, the error increases due to the inclined angle as it approaches the semiconductor light emitting device based on the z-axis, and the semiconductor light emitting device manufactured in a miniature size It may be far from the center of the element. In addition, since the pressure is applied to the semiconductor light emitting device in an inclined state, the fin and the semiconductor light emitting device can be easily damaged, and the transfer rate and removal rate are also reduced.

In contrast, in the method of repairing the semiconductor light emitting device for a pixel according to the first embodiment, the pin may be moved in the z-axis, and the pin may be vertically corrected by grasping an observed image using a depth of focus of an optical system.

In detail, (a) of FIG. 8 is a view showing a case where the pin 130 is separated from the optical system 140 by a first distance D1. The depth of focus F1 of the optical system 140 may be located at the center of the pin 130 .

(b) of FIG. 8 is a view showing a case where the pin 130 is separated from the optical system 140 by the second distance D2. At this time, the depth of focus F1 of the optical system 140 may be located at the peak 137 of the pin 130 . The peak 137 may be formed to have a smaller width than the central portion of the pin 130 .

When the pin 130 moves along the z-axis and the distance between the optical system 140 and the pin 130 changes, a portion of the optical system 140 located within the range of the depth of focus F1 may vary. The optical system 140 observes the pin 130 located within the range of the depth of focus F1, and observed data may be used to control the verticality of the pin 130.

9 is a diagram of a repair method of a semiconductor light emitting device for a pixel according to the first embodiment. Referring to (a) of FIG. 9 , when the depth of focus F1 of the optical system 140 is located in the center of the pin 130 in FIG. 8 (a), the light emitted from the optical system 140 ), it is possible to determine the image of the pin 130 as the first area 160 . The first region 160 may have a circular shape along the horizontal direction of the pin 130 and may be observed as a black image.

Referring to (b) of FIG. 9, when the depth of focus F1 of the optical system is located at the peak 137 of the pin 130 in FIG. 8 (b), the light emitted from the optical system 140 ) is reflected by the peak 137 and enters the optical system 140 again, and the image of the peak 137 of the pin 130 can be determined as the second area 165. Therefore, the repair method of the semiconductor light emitting device for pixels according to the first embodiment compares the center of the first region 160 and the center of the second region 165 to precisely control the verticality of the pin. There is a technical effect.

10 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to the first embodiment. Referring to (b) of FIG. 9, when the depth of focus of the optical system 140 is located at the peak of the pin 130, the image of the pin 130 is determined as an image of a black circle in the first area 160 The image of the peak of the pin 130 can be determined as the image of the white dot in the second area 165 .

Referring back to (a) of FIG. 10 , a vertical line AA' and a horizontal line BB' may be indicated passing through the center of the first area 160 . In addition, a vertical line aa' and a horizontal line bb' may be indicated passing through the center of the second area 165 .

When the pin 130 is not perpendicular to the optical system 140 or the stage, the vertical line AA' of the first area 160 and the vertical line aa' of the second area 165 do not coincide. The horizontal line BB' of area 1 and the horizontal line bb' of area 2 165 may not coincide.

In this case, the angle of the pressure head 120 in the tilt unit 126 may be changed by calculating the distance between the center of the first region 160 and the center of the second region 165 . An angle of the pressing head 120 may be changed so that a pin mounted on the pressing head 120 is perpendicular to the stage. Accordingly, the first embodiment has technical effects in that the verticality of the pin can be precisely controlled without using a high-magnification optical system and the repair accuracy of the subminiature semiconductor light emitting device can be improved.

Referring to (b) of FIG. 10 , it is a view showing the moment when the center of the first area 160 coincides with the center of the second area 165 . When the two regions are formed as concentric circles, the pins may mean that they are positioned perpendicularly to the stage.

When the pins are positioned vertically on the stage, the pins maintain an exact vertical relationship with the semiconductor light emitting devices when the semiconductor light emitting devices are reassembled and removed, and can come into contact with the center of the upper surface of the semiconductor light emitting devices even if the semiconductor light emitting devices are formed in a very small size. Accordingly, the first embodiment can prevent pin bending and damage to the semiconductor light emitting device during reassembly and removal processes of the semiconductor light emitting device, and can improve the reassembly rate and removal rate, respectively, even if the semiconductor light emitting device is formed in a very small size. There are complex technical effects that exist.

11 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to the first embodiment. In the process of assembling the semiconductor light emitting device, an unassembled, empty assembly hole may exist in the stage 110, and it is necessary to separately transfer the semiconductor light emitting device to the assembly hole.

Referring to FIG. 11 , a semiconductor light emitting device may be assembled on the stage 110 and a circuit pattern may be formed thereon. A film 115 is positioned on the stage 110 , and a semiconductor light emitting device 150 to be transferred to the stage 110 may be attached to the film 115 .

On the film 115, a pressure head 120 equipped with a pin 130 is positioned, and while the pressure head 120 applies pressure in the direction of the film 115, the semiconductor light emitting device 150 is removed from the film 115. can be removed and transferred onto the stage 110.

At this time, in the case of micro-LED, it is formed to be less than several tens of μm, and if the verticality of the pin is not precisely set, a large error occurs from the center of the pin and the semiconductor light emitting element when transferring the semiconductor light emitting element, so precise pressure cannot be applied. , there is a problem that can cause damage to the semiconductor light emitting device. Accordingly, the method for repairing the semiconductor light emitting device for pixels according to the first embodiment has a technical effect of increasing the transfer rate when transferring the semiconductor light emitting device by precisely controlling the verticality of the fin 130 .

12 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to the first embodiment. Referring to FIG. 12 , when the semiconductor light emitting device 150 transferred on the stage 110 is defective, it is necessary to remove the semiconductor light emitting device 150 and reassemble a good semiconductor light emitting device.

At this time, when the pin 130 mounted on the pressure head 120 is not perpendicular to the semiconductor light emitting element 150, the adhesive strength of the semiconductor light emitting element 150 to the pin 130 is reduced, It may not be removed by pin 130 . In addition, there is a problem in that the semiconductor light emitting device 150 is damaged during this process and residual materials may remain in the assembly hole.

Therefore, the first embodiment has a technical effect of improving the removal rate when removing the semiconductor light emitting device and preventing damage to the fin and the semiconductor light emitting device by correcting the fin 130 to be perpendicular to the semiconductor light emitting device.

Also, an adhesive material 135 may be applied to the tip of the pin 130 . The adhesive material has stronger adhesion to the semiconductor light emitting device 150 than the pin 130 and may include an elastic material. Accordingly, when removing the semiconductor light emitting device 150, the removal rate may be further improved, and damage to the fins and the semiconductor light emitting device may be prevented.

13 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to a second embodiment.

Referring to FIG. 13 , the second optical system 140b may be positioned in a horizontal direction between the pressure head 120 and the pin 130 . Also, the second optical system 140b may be positioned in a vertical relationship with the stage 110 . The optical system 140 can determine the center of the pin 130 close to the pressure head 120 and the center of the peak by the center measurement algorithm, and can obtain data whether the two centers are located in a vertical relationship. When an imaginary line connecting the two centers is inclined, the tilt unit changes the angle of the pressure head 120 based on the inclined angle data so that the pin 130 is in a vertical relationship with the stage 110. 130) can be adjusted.

At this time, a plurality of second optical systems 140b may be located around the pin 130 on the xy plane. In addition, the second optical system 140b rotates around the pin 130 on the xy plane and may be arranged to recognize the inclination of the pin 130 . Therefore, the repair method of the semiconductor light emitting device for pixels according to the second embodiment has a technical effect of recognizing the inclination of the pin 130 from various angles and precisely adjusting it vertically.

14 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to a third embodiment.

Referring to FIG. 14 , the lens of the third optical system 140c may be positioned parallel to the direction of the pin 130 . The third optical system 140c may observe the inclination of the pin 130 through the reflector 145 . The third optical system 140c can grasp the center of the pin 130 close to the pressure head 120 and the center of the peak by the center measurement algorithm, and can obtain data whether the two centers are located in a vertical relationship. . When an imaginary line connecting the two centers is inclined, the tilt unit changes the angle of the pressure head 120 based on the inclined angle data so that the pin 130 is in a vertical relationship with the stage 110. 130) can be adjusted. In addition, the pressure head 120 is rotated, and the inclination of the pin 130 can be observed from various angles.

Therefore, in the repair method of the semiconductor light emitting device for pixels according to the third embodiment, the third optical system 140c does not have to be located on the xy plane, so that the repair device for the semiconductor light emitting device for pixels can be miniaturized, and the pin 130 can be viewed from multiple angles. ) has the technical effect of identifying the inclination and precisely adjusting it vertically.

15 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to a fourth embodiment. In FIG. 15 , when the semiconductor light emitting device 150 is mounted on the film 115 when enlarged, an adhesive layer 117 is applied under the film 115, and the semiconductor light emitting device 150 is applied to the adhesive layer 117. attached. The film 115 may transmit light and may have fluidity.

The film 115 and the adhesive layer 117 may have non-flat and non-uniform thicknesses, and thus, the z-axis heights of the plurality of semiconductor light emitting devices 150 may be non-uniform. When the z-axis heights of the plurality of semiconductor light emitting devices 150 are different, during the repair process, when pressing the film with a pin, a difference occurs in the pressing amount, and the semiconductor light emitting device is smoothly detached from the film 115 There exists, and there is a semiconductor light emitting device that is not easily detached due to an insufficient amount of pressing, which may lead to a decrease in process yield.

In order to solve the above problem, the fourth embodiment has a technical effect of improving the reassembly rate of the semiconductor light emitting device during the repair process by identifying the z-axis height of each of the semiconductor light emitting devices and changing the pressurization conditions suitable for this. there is.

16 is a conceptual diagram of a repair method of a semiconductor light emitting device for a pixel according to a fourth embodiment. Referring to FIG. 16 , an adhesive layer 117 is applied to the film 115, and a plurality of semiconductor light emitting devices 150 may be attached to the adhesive layer 117. The plurality of semiconductor light emitting devices 150 may include first, second, third, and fourth semiconductor light emitting devices 151, 152, 153, and 154, and may include a larger number of semiconductor light emitting devices. there is.

The film 115 and the adhesive layer 117 have fluidity and may not be flat. Accordingly, positions of the z-axis relative to the heights of the first semiconductor light emitting device 151, the second semiconductor light emitting device 152, the third semiconductor light emitting device 153, and the fourth semiconductor light emitting device 150 may be different from each other. .

A fourth optical system 140d may be positioned on the film 115 . The fourth optical system 140d has a depth of focus F2 and can obtain clear images of the plurality of semiconductor light emitting devices located within the depth of focus F2. Semiconductor light emitting devices positioned outside the boundary of the depth of focus F2 acquire a blurry image or cannot acquire an image.

The fourth optical system 140d may determine data of x, y, and z coordinate values of the semiconductor light emitting devices for which clear images have been obtained.

The fourth optical system 140d may move up and down along the z-axis direction to capture a clear image of the plurality of semiconductor light emitting devices. In addition, if both position and height data of the semiconductor light emitting devices in one area of the display panel are obtained, the above process may be repeated in another area of the display panel.

FIG. 17 is a conceptual view of semiconductor light emitting devices observed in the fourth optical system 140d of FIG. 16 . (a) of FIG. 17 is a view of semiconductor light emitting devices observed through the optical system at a first height, and (b) is a view of semiconductor light emitting devices observed through the optical system at a second height.

Referring to FIG. 16 , the z-axis positions of the first semiconductor light emitting device 151, the second semiconductor light emitting device 152, the third semiconductor light emitting device 153, and the fourth semiconductor light emitting device 150 may be different from each other. .

Referring back to (a) of FIG. 17 , for example, when the depth of focus F2 of the optical system 140 is at the first height, the first semiconductor light emitting element 151 can be clearly seen and the second semiconductor light emitting device 151 can be clearly seen. The light emitting device 152 may be dimly visible, the third semiconductor light emitting device 153 may not be visible, and the fourth semiconductor light emitting device 154 may be clearly visible.

In this case, data on the x, y, and z coordinate values of the first semiconductor light emitting device 151 and the fourth semiconductor light emitting device 154 that are clearly visible in the fourth optical system 140d may be stored.

Referring to (b) of FIG. 17 , for example, when the depth of focus F2 of the fourth optical system 140d is at the second height, the first semiconductor light emitting element 151 may appear blurred, and the second The semiconductor light emitting device 152 may be clearly visible, the third semiconductor light emitting device 153 may be clearly visible, and the fourth semiconductor light emitting device 154 may be dimly visible.

In this case, data on x, y, and z coordinate values of the second semiconductor light emitting device 152 and the third semiconductor light emitting device 153 that are clearly visible in the optical system 140 may be stored.

The fourth optical system 140d may grasp the x, y, and z coordinate values of the plurality of semiconductor light emitting devices at the first height and the second height or different heights.

Therefore, the repair method of the semiconductor light emitting device for pixels according to the fourth embodiment has a technical effect of determining the location and height of non-uniformly located semiconductor light emitting devices by changing the height of the fourth optical system 140d. . Accordingly, there is a special technical effect of improving the transfer rate by changing the pressing conditions to match the heights of the semiconductor light emitting devices having different heights.

18 is a flowchart illustrating a method of repairing a semiconductor light emitting device for a pixel according to a fourth embodiment.

Referring to FIG. 18 , an optical system may be positioned on a film to which a plurality of semiconductor light emitting devices are attached. The semiconductor light emitting device may be attached to the film by an adhesive layer, and the adhesive layer and the film may not be flat because they have fluidity. Since the plurality of semiconductor light emitting devices are attached to the non-flat adhesive layer, they may be positioned at different heights. The film includes a transmissive material, and the optical system moves in the z-axis on the film while focusing on the film surface by laser focusing or image focusing.

Subsequently, the optical system has a depth of focus F2 and may be positioned at a first height toward the film by the depth of focus F2. Thereafter, the optical system may move +1 um based on the z-axis at the first height. After the optical system is moved, an image of the semiconductor light emitting device may be measured to check the sharpness and similarity of the semiconductor light emitting device. For an object presumed to be a semiconductor light emitting device, the x and y positions can be stored.

Also, the optical system may move +1 um based on the z-axis. After moving, data may be stored after determining the coordinate values of x, y, and z of the clearly observed semiconductor light emitting device. It continues to move by +1 um based on the z-axis, and when the movement from the first height to the top by the depth of focus (F2) is completed, a clear image of all semiconductor light emitting devices is obtained, and the x, y, and z of the semiconductor light emitting device are obtained. coordinates can be identified.

Therefore, it is possible to apply a pressing amount suitable for the height of each semiconductor light emitting device to the pressing head, and thus, there is a technical effect of increasing the transfer rate of the semiconductor light emitting device.

Therefore, the repair method of the semiconductor light emitting device for pixels according to the embodiment has a technical effect of increasing the assembly rate when assembling a chip.

In addition, the method for repairing a semiconductor light emitting device for a pixel according to the embodiment has a technical effect of increasing a removal rate during chip removal.

In addition, the embodiment has a technical effect of improving repair accuracy of the subminiature semiconductor light emitting device even without using a high-magnification optical system.

In addition, the embodiment has a technical effect of preventing bending of the pins mounted on the pressure head and reducing the replacement frequency of the pins.

In addition, the embodiment has a technical effect of improving the removal rate during chip removal by increasing the adhesion rate with the semiconductor light emitting device by applying an adhesive material to the tip of the pin.

In addition, the embodiment has a technical effect of precisely controlling the verticality of the pin even if the optical system is located at the bottom, side, or top of the pin.

In addition, the method for repairing a semiconductor light emitting device for a pixel according to the embodiment has a technical effect of being able to locate randomly arranged semiconductor light emitting devices.

In addition, the embodiment has a technical effect of determining the z-axis positions of semiconductor light emitting elements having different z-axis positions.

In addition, the embodiment has a technical effect of improving the process yield by changing the pressurization conditions according to the z-axis position of the semiconductor light emitting devices.

The above detailed description should not be construed as limiting in all respects 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 range of the embodiments are included in the scope of the embodiments.

20: drive circuit
21: data driving unit
22: timing control unit
100: display device
PX: pixels
PX1: first sub-pixel
PX2: second sub-pixel
PX3: third sub-pixel
Cst: capacitor
DT: drive transistor
A1: first panel area
201, 202: assembly wiring
110: panel
115: film
117: adhesive layer
120: press head
121: first pressure head
122: second pressure head
123: third pressure head
125: stage
126: tilt unit
127: first tilt unit
128: second tilt unit
129: third tilt unit
130: pin
131: first pin
132: second pin
133: third pin
135: elastic material
137: peak
140: optical system
145: reflector
150: semiconductor light emitting element
151: first semiconductor light emitting element
152: second semiconductor light emitting element
153: third semiconductor light emitting element
154: fourth semiconductor light emitting element
160: first area
165 second area

Claims (10)

disposing a pressure head having pins on an optical system;
moving the pressure head from a first height to a second height; and
Observing the image of the pin from the first height to the second height with the optical system; including,
the first image of the pin at the first height represents a first area;
a second image of the pin at the second height represents a second area;
and tilting the pressure head so that a center of the first region coincides with a center of the second region. According to claim 1,
The first height is such that the depth of focus of the optical system is located at the center of the pin,
The second height is a height at which the depth of focus of the optical system is located at the peak of the pin, the repair method of the semiconductor light emitting device for a pixel. According to claim 1,
The method of repairing a semiconductor light emitting device for a pixel, further comprising pressing the semiconductor light emitting device with the pin after tilting the pressing head. According to claim 3,
The method of repairing a semiconductor light emitting device for a pixel, characterized in that the fin is in a vertical relationship with the semiconductor light emitting device. According to claim 1,
The repair method of a semiconductor light emitting device for a pixel, characterized in that the first region and the second region are concentric circles. According to claim 1,
The pressure head and the pin include a plurality,
In the step of tilting the pressure head, at least one of the plurality of pressure heads is tilted. arranging an optical system at a third height on a plurality of semiconductor light emitting devices adhered to the film;
obtaining a clear image of at least one of the plurality of semiconductor light emitting devices with the optical system;
obtaining data on a z-axis height of at least one of the plurality of semiconductor light emitting devices corresponding to the clear image;
moving the optical system by a predetermined height in the z-axis direction; and
Acquiring a clear image of at least one other of the plurality of semiconductor light emitting devices with the optical system; including, a repair method of a semiconductor light emitting device for a pixel. According to claim 7,
The step of moving the optical system by a predetermined height in the z-axis direction is repeated until the optical system is located at the fourth height,
A difference between the third height and the fourth height is at least twice the depth of focus range of the optical system. According to claim 8,
The plurality of semiconductor light emitting elements are located within the depth of focus range of the optical system, a method of repairing a semiconductor light emitting element for a pixel. According to claim 7,
After obtaining data on the z-axis height of at least one of the plurality of semiconductors, the method of repairing a semiconductor light emitting device for a pixel further comprising the step of changing a pressing condition to correspond to the z-axis height.

Images