KR20230127458A - Vertical alignment assembly of light emitting device and method of vertically aligning light emitting device - Google Patents

Abstract

The light emitting device vertical alignment assembly includes an LED chip including a first conductivity-type semiconductor layer, an active layer, a second conductivity-type semiconductor layer, and a magnetic layer, an alignment substrate to which the LED chip is coupled, a magnet forming a magnetic field in a first direction, and It may include a pair of barrier ribs disposed in the fluid layer. The LED chip may be supplied into the pair of barrier ribs, seated on the alignment substrate by the uniform magnetic field in the first direction, and bonded to the alignment substrate by forming a junction with the alignment substrate.
The light emitting device vertical alignment assembly forms a magnetic field using a magnet in the fluid layer including the LED chip and the alignment substrate, so that the LED chip can be quickly and accurately transferred onto the alignment substrate by the magnetic field.

Description

Light emitting device vertical alignment assembly and light emitting device vertical alignment method

The present invention relates to a method for vertically aligning light emitting devices, and more particularly, to a light emitting device vertical alignment assembly using a magnetic field and a method for vertically aligning light emitting devices using a magnetic field.

Apple of the United States acquired Ruxvue Technology, a company specializing in micro light emitting devices in 2014, and the possibility of applying micro light emitting devices to displays is being realized due to the release of micro light emitting device pixel TV prototypes by Sony of Japan and Baco of China. If a high-speed transfer process/equipment is developed in the future, it is expected to become a next-generation flexible lighting and display that surpasses micro light emitting devices.

The micro/nano micro light emitting devices used in these displays are chemically stable and bio-compatible, and can be attached to or inserted into the body to be applied to various biomedical fields such as cell stimulation, optogenetic treatment, wound treatment and diagnosis. In addition, it can be used as a wearable optical assist device by being implanted in smart textiles, bio contact lenses, head mounted displays, medical patches, as well as electronic devices integrated with biological tissues.

In order to manufacture a flexible micro/nano micro light emitting device, a process of transferring separated micro light emitting device chips to a substrate in a desired arrangement is essential. Currently, the main development direction is an electrostatic pickup method developed by Ruxvue Technology and a pickup method using an elastic polymer material as a printer head reported by the Rogers group of UIUC University, but the pick-and-place method has problems with chip damage and low throughput. There are fundamental limitations. In addition, there is no company in the world that has commercialized the inorganic GaN-based micro light emitting device transfer process at a mass production level.

Korean Patent Registration No. 10-2127559 "Magnetic transfer device, manufacturing method of magnetic transfer device, semiconductor light emitting element transfer method using magnetic transfer device"

One object of the present invention is to provide a light emitting device vertical alignment assembly that quickly and accurately transfers LED chips onto an alignment substrate using a magnetic field.

Another object of the present invention is to provide an LED chip structure and an alignment substrate structure for quickly and accurately transferring the LED chips onto an alignment substrate.

Another object of the present invention is to provide a method for vertically aligning light emitting devices that quickly and accurately transfers LED chips onto an alignment substrate using a magnetic field.

However, the problem to be solved by the present invention is not limited to the above-mentioned problem, and may be expanded in various ways without departing from the spirit and scope of the present invention.

In order to achieve one object of the present invention, a light emitting device vertical alignment assembly according to embodiments of the present invention is an LED chip including a first conductivity type semiconductor layer, an active layer, a second conductivity type semiconductor layer, and a magnetic layer, the It may include an alignment substrate to which the LED chip is coupled, a magnet forming a magnetic field in a first direction, and a pair of barrier ribs disposed in the fluid layer. The LED chip may be supplied into the pair of barrier ribs, seated on the alignment substrate in a uniform magnetic field in the first direction, and bonded to the alignment substrate by forming a junction with the alignment substrate.

In one embodiment, the magnet may be a single magnet that is disposed below the alignment substrate and induces the LED chip to move downward by forming a magnetic field in the first direction.

In one embodiment, the magnet may include an upper magnet and a lower magnet. The upper magnet and the lower magnet may be disposed in parallel. The N pole of the upper magnet and the S pole of the lower magnet may form a magnetic field in the first direction.

In one embodiment, a distance between the pair of barrier ribs may be shorter than a width of the magnet. The pair of barrier ribs blocks the LED chip from moving outside the uniform magnetic field region in the first direction, so that the LED chip can be accurately seated on the alignment substrate.

In one embodiment, the alignment substrate may move in a horizontal direction. The LED chips may be sequentially coupled to coupling parts of the alignment substrate as the alignment substrate moves in a horizontal direction.

In one embodiment, the magnet and the pair of barrier ribs may move in a horizontal direction. The LED chip may be sequentially coupled to the coupling portion of the alignment substrate as the magnet and the pair of barrier ribs move in a horizontal direction.

In one embodiment, the LED chip may have a first shape in which a width gradually increases toward the first conductivity-type semiconductor layer, the active layer, and the second conductivity-type semiconductor layer according to an ICP etching process.

In one embodiment, a supply nozzle supplying the LED chip to the fluid layer may be further included.

In one embodiment, the fluid layer to which the LED chip is supplied may include a first fluid and a second fluid. The first fluid may be a hydrophobic fluid, the second fluid may be a hydrophilic fluid, and the first fluid may be positioned above the second fluid.

In one embodiment, as the LED chip is subjected to surface treatment, the first conductivity-type semiconductor layer, the active layer, and the second conductivity-type semiconductor layer are coated with a hydrophobic material, and the magnetic layer is coated with a hydrophilic material. can

In one embodiment, in the LED chip, the first conductivity-type semiconductor layer coated with the hydrophobic material, the active layer, and the second conductivity-type semiconductor layer are formed at the interface between the first fluid and the second fluid. By rotating to be placed in the first fluid, and the magnetic layer coated with the hydrophilic material is rotated to be placed in the second fluid, it can be vertically aligned.

In one embodiment, the alignment substrate may include a coupling portion to which the LED chips are coupled, a coupling guide portion including an inclined surface, and a bonding metal forming a eutectic junction with the LED chips.

In one embodiment, the coupling inducer may have a second shape having a shape specificity with the first shape of the LED chip. The LED chip may be vertically aligned on the coupling portion by the second shape of the coupling guide portion.

In order to achieve another object of the present invention, a method for vertically aligning light emitting devices according to embodiments of the present invention includes manufacturing an LED chip, performing surface treatment on the LED chip, and vertically aligning the LED chip in a fluid. eutectic melting of the bonding metal, seating the LED chip on the alignment substrate using a magnetic field, and forming a eutectic junction between the LED chip and the bonding metal to attach the LED chip to the alignment substrate. It may include a bonding step. In the step of seating the LED chip on the alignment substrate using the magnetic field, a magnetic field in a first direction is formed and the LED chip is moved in the first direction using the magnetic field in the first direction, thereby moving the LED chip in the first direction. It may be seated on the alignment substrate.

In the light emitting device vertical alignment assembly and the light emitting device vertical alignment method according to embodiments of the present invention, a magnetic field may be formed by using a magnet in a fluid layer including an LED chip and an alignment substrate. The LED chip can be quickly and accurately transferred onto the alignment substrate by the magnetic field.

Therefore, according to the present invention, it is possible to overcome the fundamental limitations of the pick-and-place transfer method, which has problems with damage to the micro light emitting device chip and low throughput, and it is possible to overcome the process time required for electrode connection after transfer. can be shortened and defective pixels can be simply repaired, and micro/nano micro light emitting device lighting and displays can be realized by commercializing the inorganic GaN-based micro light emitting device transfer process to the level of mass production.

However, the effects of the present invention are not limited to the above-described effects, and may be variously extended within a range that does not deviate from the spirit and scope of the present invention.

1 is a view showing a light emitting device vertical alignment assembly according to embodiments of the present invention.
FIG. 2 is a top plan view of the light emitting device vertical alignment assembly of FIG. 1 .
FIG. 3 is a flowchart illustrating an operation of the light emitting device vertical alignment assembly of FIG. 1 .
FIG. 4 is a view for explaining each step of the light emitting device vertical alignment assembly according to the flowchart of FIG. 3 .
5 is a view showing an embodiment of the LED chip of the present invention.
6 is a view showing a process of vertically aligning LED chips in a fluid layer.
7 is a view showing a pair of barrier ribs that shield a magnet and a magnetic field that forms a magnetic field.
8 is a view showing an embodiment of an alignment substrate of the present invention.
9 is a view showing a first embodiment in which LED chips are sequentially coupled to an alignment substrate.
10 is a view showing a second embodiment in which LED chips are sequentially coupled to an alignment substrate.

Specific structural or functional descriptions of the embodiments according to the concept of the present invention disclosed in this specification are only illustrated for the purpose of explaining the embodiments according to the concept of the present invention, and the embodiments according to the concept of the present invention These may be embodied in various forms and are not limited to the embodiments described herein.

Embodiments according to the concept of the present invention can apply various changes and can have various forms, so the embodiments are illustrated in the drawings and described in detail herein. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosures, and includes modifications, equivalents, or substitutes included in the spirit and scope of the present invention.

Terms such as first or second may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another component, for example, without departing from the scope of rights according to the concept of the present invention, a first component may be named a second component, Similarly, the second component may also be referred to as the first component.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle. Expressions describing the relationship between components, such as "between" and "directly between" or "directly adjacent to" should be interpreted similarly.

Terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate that the described feature, number, step, operation, component, part, or combination thereof exists, but one or more other features or numbers, It should be understood that the presence or addition of steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in this specification, it should not be interpreted in an ideal or excessively formal meaning. don't

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, the scope of the patent application is not limited or limited by these examples. Like reference numerals in each figure indicate like elements.

FIG. 1 is a view showing a light emitting device vertical alignment assembly according to embodiments of the present invention, and FIG. 2 is a top plan view of the light emitting device vertical alignment assembly of FIG. 1 .

1 and 2, the light emitting device vertical alignment assembly according to embodiments of the present invention includes an LED chip 100, an alignment substrate 200 to which the LED chip 100 is coupled, and the LED chip 100. It may include a supply nozzle 300 supplying a fluid layer, a magnet 400 forming a magnetic field, and a pair of barrier ribs 500 shielding the magnetic field.

The LED chip 100 may be coupled to the alignment substrate 200 by being supplied to the fluid layer and moving by a magnetic field.

For example, the LED chips 100 may be vertically aligned by a density difference in a fluid layer.

For example, the LED chip 100 may be coupled to the alignment substrate 200 by forming a eutectic junction with the alignment substrate 200 .

The alignment substrate 200 includes a coupling portion 210 to which the LED chips 100 are coupled, a coupling induction portion 220 including an inclined surface, and a bonding metal 230 forming a eutectic junction with the LED chips 100. can do.

For example, the alignment substrate 200 may induce the LED chip 100 to be accurately seated by using an inclined surface.

For example, the alignment substrate 200 may couple the LED chip 100 by forming a eutectic junction with the LED chip 100 .

The supply nozzle 300 may supply the LED chip 100 to the fluid layer. For example, the supply nozzle 300 may supply a plurality of LED chips 100 to the fluid layer through a plurality of supply lines.

The fluid layer to which the LED chip 100 is supplied may include a first fluid FL1 and a second fluid FL2. The first fluid FL1 and the second fluid FL2 may be fluids having different densities.

The LED chip 100 may be vertically aligned according to a difference in density at the interface between the first fluid FL1 and the second fluid FL2.

The magnet 400 may form a magnetic field in a first direction and move the LED chip 100 in the first direction by using the magnetic field in the first direction.

For example, the magnet 400 may be an electromagnet. For example, the magnet 400 may be a permanent magnet.

The magnet 400 may be composed of a single magnet. For example, the magnet 400 may be a single magnet disposed below the alignment substrate 200 and inducing the LED chip 100 to move downward by forming a magnetic field in the first direction.

The magnet 400 may include an upper magnet 410 and a lower magnet 420 . For example, the upper magnet 410 may be disposed above the fluid layer to which the LED chip 100 is supplied. For example, the lower magnet 420 may be disposed below the fluid layer to which the LED chip 100 is supplied.

The upper magnet 410 and the lower magnet 420 may be disposed parallel to each other. A magnetic field in the first direction may be formed between the upper magnet 410 and the lower magnet 420 . For example, the first direction may be a direction in which the LED chip 100 is accurately seated on the alignment substrate 200 .

A pair of barrier ribs 500 may be disposed in a direction perpendicular to the fluid layer. A distance between the pair of barrier ribs 500 may be shorter than a width of the magnet 400 .

The pair of barrier ribs 500 block the movement of the LED chip 100 out of the uniform magnetic field region in the first direction, so that the LED chip 100 can be accurately seated on the alignment substrate 200 .

In addition, the pair of barrier ribs 500 can prevent the LED chips 100 from being magnetized and sticking together.

For example, the pair of barrier ribs 500 minimize the effect of a magnetic field in a direction different from the first direction on the LED chip 100, so that the LED chip 100 is aligned with the magnetic field in the first direction ( 200) can be induced to settle.

In this way, the light emitting device vertical alignment assembly according to embodiments of the present invention forms a magnetic field in the fluid layer including the LED chip 100 and the alignment substrate 200 using the magnet 400, so that the LED chip 100 ) can be quickly and accurately transferred onto the alignment substrate 200 by a magnetic field.

FIG. 3 is a flow chart showing the operation of the light emitting device vertical alignment assembly of FIG. 1 , and FIG. 4 is a diagram for explaining each step of the light emitting device vertical alignment assembly according to the flow chart of FIG. 3 .

5 is a view showing an embodiment of the LED chip 100 of the present invention, FIG. 6 is a view showing a process in which the LED chip 100 is vertically aligned in a fluid layer, and FIG. 7 is a magnet forming a magnetic field ( 400) and a pair of barrier ribs 500 for shielding a magnetic field, and FIG. 8 is a view showing an embodiment of an alignment substrate 200 according to the present invention.

3 and 4, the light emitting device vertical alignment assembly manufactures the LED chip 100 (S100), performs surface treatment on the LED chip 100 (S200), and turns the LED chip 100 into a fluid. Vertical alignment within the layer (S300), eutectic melting of the bonding metal 230 (S400), mounting the LED chip 100 on the alignment substrate 200 using a magnetic field (S500), and ) and the bonding metal 230 to form a eutectic junction to couple the LED chip 100 to the alignment substrate 200 (S600).

In one embodiment, the light emitting device vertical alignment assembly may manufacture the LED chip 100 (S100). Specifically, the LED chip 100 may include a first conductivity type semiconductor layer 110 , an active layer 120 , a second conductivity type semiconductor layer 130 , and a magnetic layer 140 .

The first conductivity-type semiconductor layer 110 and the second conductivity-type semiconductor layer 130 may be made of materials such as GaN, AlGaN, and InGaN. For example, Si, Ge, Se, Te, or the like may be used as the n-type impurity. For example, Mg, Zn, Be, etc. may be used as the p-type impurity.

The first conductivity-type semiconductor layer 110 and the second conductivity-type semiconductor layer 130 may be formed through MOCVD, MBE, or HVPE processes.

The active layer 120 may emit light having a predetermined energy by recombination of electrons and holes. For example, the active layer 120 may be a layer made of a single material such as InGaN. For another example, the active layer 120 may have a multiple quantum well (MQW) structure in which quantum barrier layers and quantum well layers are alternately disposed.

The magnetic layer 140 may be made of a metal having magnetism. The magnetic layer 140 may be formed on the second conductivity type semiconductor layer 130 . The magnetic layer 140 may be magnetized to move the LED chip 100 .

For example, the magnetic layer 140 may induce the LED chip 100 to be seated on the alignment substrate 200 by moving the LED chip 100 in the direction of the magnetic field.

Referring to FIG. 5 , the LED chip 100 has a width toward the first conductive semiconductor layer 110 , the active layer 120 , and the second conductive semiconductor layer 130 according to an ICP etching process. It may have a first shape that gradually widens.

The first shape may include an inclined surface. For example, the first shape may be a trapezoidal shape. For example, the first shape may be a pyramid shape.

Since the LED chip 100 has a first shape according to the ICP etching process, it can be accurately and quickly seated on the alignment substrate 200 .

In one embodiment, the light emitting device vertical alignment assembly may perform surface treatment on the LED chip 100 (S200), and vertically align the LED chip 100 in the fluid layer (S300). Specifically, the LED chip 100 may be vertically aligned so that the magnetic layer 140 faces the alignment substrate 200 due to the difference in density of the fluid layer.

The fluid layer to which the LED chip 100 is supplied may include a first fluid FL1 and a second fluid FL2. The first fluid FL1 and the second fluid FL2 may be fluids having different densities.

The first fluid FL1 may be a hydrophobic fluid, and the second fluid FL2 may be a hydrophilic fluid. For example, the first fluid FL1 may include an oil component, and the second fluid FL2 may include a water component.

According to the density difference between the first fluid FL1 and the second fluid FL2 in the fluid layer, the hydrophobic first fluid FL1 may be formed in the upper layer and the hydrophilic second fluid FL2 may be formed in the lower layer. .

The surface of the LED chip 100 may be treated with a hydrophobic material or a hydrophilic material. For example, as the surface treatment of the LED chip 100 is performed, the first conductivity type semiconductor layer 110, the active layer 120, and the second conductivity type semiconductor layer 130 are coated with a hydrophobic material, , The magnetic layer 140 may be coated with a hydrophilic material.

The LED chip 100 may be vertically aligned according to a density difference at the interface between the first fluid FL1 and the second fluid FL2. Specifically, the LED chip 100 moves from the first fluid FL1 in the upper layer to the second fluid FL2 in the lower layer, according to the density difference between the first fluid FL1 and the second fluid FL2. Referring to FIG. 6, the magnetic layer 140 coated with a hydrophilic material is rotated to be placed on the second fluid FL2, and the first conductive semiconductor layer 110 coated with a hydrophobic material, The active layer 120 and the second conductivity-type semiconductor layer 130 may rotate to be placed in the first fluid FL1.

For example, in the fluid layer, the magnetic layer 140 is directed toward the alignment substrate 200, and the first conductivity type semiconductor layer 110, the active layer 120, and the second conductivity type semiconductor layer 130 are aligned. It may face in the opposite direction of the substrate 200 .

Accordingly, the LED chip 100 may be vertically aligned by itself at the interface between the first fluid and the second fluid.

In one embodiment, the light emitting device vertical alignment assembly may eutectic melt the bonding metal 230 (S400). Specifically, the bonding metal 230 of the alignment substrate 200 may be eutectic melted to form a bond with the LED chip 100 .

The bonding metal 230 may be formed on the coupling part 210 of the alignment substrate 200 . The junction metal 230 may include tin (Sn), lead (Pb), copper (Cu), gold (Au), silicon (Si), or the like.

For example, the bonding metal 230 may be formed of tin, lead, copper, gold, silicon, and combinations thereof to form eutectic bonding with the LED chip 100 .

In one embodiment, the light emitting device vertical alignment assembly may seat the LED chip 100 on the alignment substrate 200 using a magnetic field (S500).

Specifically, the magnet 400 forms a magnetic field in a first direction, and moves the LED chip 100 in the first direction using the magnetic field in the first direction, thereby aligning the LED chip 100. It can be seated on the substrate 200 .

For example, the magnet 400 may be an electromagnet. For example, the magnet 400 may be a permanent magnet.

The magnet 400 may include an upper magnet 410 and a lower magnet 420 . The upper magnet 410 and the lower magnet 420 may be disposed in parallel.

A magnetic field may be formed between the upper magnet 410 and the lower magnet 420 . For example, the N pole of the upper magnet 410 and the S pole of the lower magnet 420 may form a magnetic field in the first direction. For example, the first direction may be a direction in which the LED chip 100 is accurately seated on the alignment substrate 200 .

Since the LED chip 100 includes the magnetic layer 140 , the magnetic layer 140 may be moved near the alignment substrate 200 according to the magnetic field in the first direction. Therefore, the LED chip 100 can be quickly and accurately transferred onto the alignment substrate 200 under the influence of the magnetic field.

Meanwhile, a magnetic field in another direction may be formed between the upper magnet 410 and the lower magnet 420 in addition to the magnetic field in the first direction. A magnetic field in a direction different from the first direction may adversely affect the transfer of the LED chip 100, such as moving the LED chip 100 in a direction other than the first direction or magnetizing the LED chip 100 to make them stick together. can

Referring to FIG. 7 , a pair of barrier ribs 500 may be vertically disposed in the fluid layer. A distance between the pair of barrier ribs 500 may be shorter than a width of the magnet 400 . The pair of barrier ribs 500 may shield unnecessary magnetic fields when the LED chips 100 are vertically aligned.

The pair of barrier ribs 500 block the movement of the LED chip 100 out of the uniform magnetic field region in the first direction, so that the LED chip 100 can be accurately seated on the alignment substrate 200 .

In addition, the pair of barrier ribs 500 can prevent the LED chips 100 from being magnetized and sticking together.

The pair of barrier ribs 500 minimize the effect of a magnetic field in a direction different from the first direction on the LED chip 100, so that the LED chip 100 is seated on the alignment substrate 200 according to the magnetic field in the first direction. can motivate you to do it.

For example, the pair of barrier ribs 500 filter the magnetic field formed between the upper magnet 410 and the lower magnet 420 into a uniform magnetic field in the first direction, and the LED chip 100 supplied therein ) can be induced to move in the first direction.

In one embodiment, the light emitting device vertical alignment assembly forms a eutectic junction between the LED chip 100 and the bonding metal 230 to couple the LED chip 100 to the alignment substrate 200 (S600) can do.

Referring to FIG. 8 , the alignment substrate 200 includes a coupling portion 210 to which the LED chip 100 is coupled, a coupling induction portion 220 including an inclined surface, and a junction forming a eutectic junction with the LED chip 100. It may include metal 230 .

The coupling portion 210 may be a portion of the alignment substrate 200 to which the LED chip 100 is substantially coupled. A coupling guide portion 220 and a bonding metal 230 may be formed on the coupling portion 210 .

The coupling induction unit 220 may have a second shape having a shape specificity with the first shape of the LED chip 100 . For example, the coupling induction unit 220 may have a second shape that induces the inclined surface of the first shape of the LED chip 100 to be slid and inserted into the coupling unit 210 .

Accordingly, the LED chip 100 may be vertically aligned on the coupling part 210 by the second shape of the coupling inducing part 220 .

The junction metal 230 may form a junction with the LED chip 100 by being eutectic melted. For example, the bonding metal 230 may form eutectic bonding with the LED chip 100 .

9 is a view showing a first embodiment in which the LED chips 100 are sequentially coupled to the alignment substrate 200 .

Referring to FIG. 9 , the alignment substrate 200 may move in a horizontal direction. At this time, since the positions of the magnet 400 and the pair of barrier ribs 500 are fixed, the LED chip 100 may descend sequentially in a vertical downward direction.

The LED chip 100 may be sequentially coupled to the coupling part 210 of the alignment substrate 200 as the alignment substrate 200 moves in a horizontal direction.

That is, as the alignment substrate 200 moves in the horizontal direction, the LED chips 100 may be evenly coupled to the alignment substrate 200 without overlapping each other.

10 is a view showing a second embodiment in which the LED chips 100 are sequentially coupled to the alignment substrate 200 .

Referring to FIG. 10 , the magnet 400 and the pair of barrier ribs 500 may move in a horizontal direction. The LED chip 100 may move vertically downward and horizontally as the magnet 400 and the pair of barrier ribs 500 move in the horizontal direction.

At this time, since the position of the alignment substrate 200 is fixed, the LED chip 100 moves along the alignment substrate 200 as the magnet 400 and the pair of barrier ribs 500 move in the horizontal direction. It may be sequentially coupled to the coupling part 210 .

That is, as the magnet 400 and the pair of barrier ribs 500 move in the horizontal direction, the LED chips 100 may be evenly coupled to the alignment substrate 200 without overlapping each other.

As such, in the light emitting device vertical alignment assembly and the light emitting device vertical alignment method according to embodiments of the present invention, a magnetic field is formed by using a magnet 400 in a fluid layer including an LED chip 100 and an alignment substrate 200. can do. Therefore, the LED chip 100 can be quickly and accurately transferred onto the alignment substrate 200 by the magnetic field.

According to the present invention, it is possible to overcome the fundamental limitations of the pick-and-place transfer method, which has problems with micro light emitting device chip damage and low throughput, and shortens the process time by not requiring an additional process for connecting electrodes after transfer. and simple repair of defective pixels, and commercialization of inorganic GaN-based micro light emitting device transfer process to mass production level to realize micro/nano micro light emitting device lighting and display.

The devices described above may be implemented as hardware components, software components, and/or a combination of hardware components and software components. For example, devices and components described in the embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), It may be implemented using one or more general purpose or special purpose computers, such as a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions. A processing device may run an operating system (OS) and one or more software applications running on the operating system. A processing device may also access, store, manipulate, process, and generate data in response to execution of software. For convenience of understanding, there are cases in which one processing device is used, but those skilled in the art will understand that the processing device includes a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that it can include. For example, a processing device may include a plurality of processors or a processor and a controller. Other processing configurations are also possible, such as parallel processors.

As described above, although the embodiments have been described with limited drawings, those skilled in the art can make various modifications and variations from the above description. For example, the described techniques may be performed in an order different from the method described, and/or components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved.

Therefore, other implementations, other embodiments, and equivalents of the claims are within the scope of the following claims.

100: LED chip 110: first conductivity type semiconductor layer
120: active layer 130: second conductivity type semiconductor layer
140: magnetic layer 200: alignment substrate
210: coupling unit 220: coupling induction unit
230: bonding metal 300: supply nozzle
400: magnet 410: upper magnet
420: lower magnet 500: a pair of bulkheads
FL1: first fluid FL2: second fluid

Claims (14)

An LED chip including a first conductivity type semiconductor layer, an active layer, a second conductivity type semiconductor layer, and a magnetic layer;
an alignment substrate to which the LED chip is coupled;
a magnet forming a magnetic field in a first direction; and
Including a pair of partition walls disposed in the fluid layer,
The LED chip,
characterized in that it is supplied to the inside of the pair of barrier ribs, is seated on the alignment substrate by the uniform magnetic field in the first direction, and is coupled to the alignment substrate by forming a junction with the alignment substrate,
Light emitting element vertical alignment assembly. According to claim 1,
Characterized in that the magnet is a single magnet disposed below the alignment substrate and inducing the LED chip to move downward by forming a magnetic field in the first direction.
Light emitting element vertical alignment assembly. According to claim 1,
The magnet includes an upper magnet and a lower magnet,
The upper magnet and the lower magnet are disposed in parallel,
Characterized in that the N pole of the upper magnet and the S pole of the lower magnet form a magnetic field in the first direction,
Light emitting element vertical alignment assembly. According to claim 2 or 3,
The distance between the pair of barrier ribs is shorter than the width of the magnet,
The pair of barrier ribs blocks the LED chip from moving outside the uniform magnetic field region in the first direction, so that the LED chip is accurately seated on the alignment substrate.
Light emitting element vertical alignment assembly. According to claim 1,
The alignment substrate moves in a horizontal direction,
Characterized in that the LED chip is sequentially coupled to the coupling part of the alignment substrate as the alignment substrate moves in the horizontal direction.
Light emitting element vertical alignment assembly. According to claim 1,
The magnet and the barrier rib move in a horizontal direction,
Characterized in that the LED chip is sequentially coupled to the coupling part of the alignment substrate as the magnet and the pair of barrier ribs move in a horizontal direction.
Light emitting element vertical alignment assembly. According to claim 1,
Characterized in that the LED chip has a first shape in which a width gradually widens toward the first conductivity-type semiconductor layer, the active layer, and the second conductivity-type semiconductor layer according to an ICP etching process.
Light emitting element vertical alignment assembly. According to claim 1,
Characterized in that it further comprises a supply nozzle for supplying the LED chip to the fluid layer,
Light emitting element vertical alignment assembly. According to claim 1,
The fluid layer to which the LED chip is supplied includes a first fluid and a second fluid,
The first fluid is a hydrophobic fluid,
The second fluid is a hydrophilic fluid,
Characterized in that the first fluid is located on top of the second fluid,
Light emitting element vertical alignment assembly. According to claim 9,
As the LED chip is subjected to surface treatment, the first conductivity-type semiconductor layer, the active layer, and the second conductivity-type semiconductor layer are coated with a hydrophobic material, and the magnetic layer is coated with a hydrophilic material.
Light emitting element vertical alignment assembly. According to claim 10,
The LED chip is at the interface between the first fluid and the second fluid,
The first conductivity-type semiconductor layer, the active layer, and the second conductivity-type semiconductor layer coated with the hydrophobic material are rotated to be placed in the first fluid, and the magnetic layer coated with the hydrophilic material is rotated to be placed in the second fluid. Characterized in that it is vertically aligned by rotating to be placed on
Light emitting element vertical alignment assembly. According to claim 1,
The alignment substrate,
Coupling part to which the LED chip is coupled;
Coupling inducer including an inclined surface; and
Characterized in that it comprises a bonding metal forming a eutectic junction with the LED chip,
Light emitting element vertical alignment assembly. According to claim 12,
The coupling induction unit has a second shape having a shape specificity with the first shape of the LED chip,
Characterized in that the LED chip is vertically aligned on the coupling portion by the second shape of the coupling induction portion,
Light emitting element vertical alignment assembly. Manufacturing an LED chip;
performing a surface treatment on the LED chip;
vertically aligning the LED chips in a fluid;
eutectic melting the joining metal;
seating the LED chip on an alignment substrate using a magnetic field; and
Forming a eutectic junction between the LED chip and the bonding metal to couple the LED chip to the alignment substrate;
The step of seating the LED chip on the alignment substrate using the magnetic field,
Characterized in that the LED chip is seated on the alignment substrate by forming a magnetic field in a first direction and moving the LED chip in the first direction using the magnetic field in the first direction.
A method for vertically aligning light emitting devices.

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