KR20200117813A - Micro LED and manufacturing method of the same - Google Patents

Abstract

Disclosed are a micro-LED and a method of manufacturing the same. According to one embodiment of the present invention, provided is a method of manufacturing a micro-LED. The method comprises: a growth substrate arrangement step; a step of depositing an epitaxial layer consisting of a plurality of layers on the growth substrate; and a step of separating the epitaxial layer and forming a unit LED chip. In the step of depositing the epitaxial layer, a step of arranging a dislocation growth prevention mask in a region within the epitaxial layer corresponding to a region in which the unit LED is to be formed is conducted so as to prevent an electric potential formed on the epitaxial layer from reaching the unit LED chip, and the width of the dislocation growth prevention mask is equal to or greater than the width of the unit LED chip.

Description

Micro LED and manufacturing method thereof TECHNICAL FIELD

The present disclosure relates to a micro LED and a method of manufacturing the same.

The content described in this section merely provides background information on the present disclosure and does not constitute prior art.

LED (Light Emitting Diode) is eco-friendly, has superior energy saving effect compared to conventional lighting equipment, and has a long lifespan.

Recently, LEDs are used in a wide range of areas such as low-power driving flexible displays, attached information display devices for human body monitoring, bio-reaction and DNA sensing, bio-fusion fields for validating optogenetics, and photonics textile fields that combine conductive fibers and LED light sources. It is recognized as possible.

On the other hand, micro LED means an LED whose size is less than about 100um.

Such a micro LED has the advantage of being able to prevent the LED chip from being broken even when the panel on which the LED chip is disposed is bent because the LED chip is manufactured as small as tens of micrometers.

In addition, the micro LED can have flexibility by transferring the LED chip to a flexible substrate in the manufacturing process, so it can be widely applied to various applications including flexible displays, wearable devices, and medical devices for human body insertion.

Meanwhile, in FIG. 1, a configuration of a general LED or micro LED is shown.

Typical LEDs include a growth substrate 10, a buffer layer 21, a first conductive semiconductor layer 22, a MQW (Multi Quantum Wells) layer 23, a second conductive semiconductor layer 24 and an electrode 30, etc. Includes.

In addition, a general LED can be classified into a lateral type shown in FIG. 1A and a vertical type shown in FIG. 1B according to its shape and manufacturing method.

Such an LED includes an epitaxial layer 20 including a buffer layer 21, a first conductive semiconductor layer 22, an MQW layer 23, and a second conductive semiconductor layer 24 on the growth substrate 10. It is manufactured in a way of growing, and in the process of growing each layer, a dislocation is inevitably formed inside the epi layer 20.

At this time, a potential that starts to be formed in the buffer layer 21 of the epi layer 20 and affects each of the conductive semiconductor layers and the MQW layer may deteriorate the light emitting performance of the LED.

As such, an LED chip whose light emission performance is degraded due to the formation of a potential on the epi layer 20 of the LED can be classified as a defective LED, and an increase in the production of defective LEDs during LED production causes an increase in manufacturing cost and a decrease in manufacturing efficiency. .

On the other hand, the problem of producing a defective LED in which an electric potential is formed in the epi layer 20 may be more prominent in a micro LED chip having a smaller size, not a conventional LED having a relatively large size.

This is because in the micro LED, the potential formed in the epi layer 20 during the LED manufacturing process has a greater influence on individual LED chips than in the conventional LED chip due to the miniaturization of the LED chip.

Accordingly, the present invention has a main object to provide a micro LED manufacturing method and a micro LED manufactured by the above manufacturing method so as to minimize the effect of the potential formed in the epi layer on the unit LED chip when growing the epi layer.

According to an embodiment of the present invention, the steps of arranging a growth substrate, depositing an epitaxial layer composed of a plurality of layers on the growth substrate, separating the epitaxial layer and forming a unit LED chip are performed. And a dislocation growth prevention mask in a region in the epi layer corresponding to a region in which the unit LED chip is to be formed so as to prevent a potential formed on the epi layer from reaching the unit LED chip in the step of depositing the epi layer. A process of arranging is performed, and the width of the dislocation growth prevention mask is provided with a method of manufacturing a micro LED, which is greater than or equal to the width of the unit LED chip.

1 is a front cross-sectional view illustrating a state in which an epi layer including a plurality of layers is formed on a growth substrate in a general manufacturing process of an LED structure.
2 is a front cross-sectional view illustrating a state in which a dislocation is formed on an epi layer and a dislocation growth prevention region in a method of manufacturing a micro LED according to an embodiment of the present invention.
3 is a flow chart showing each step of a method of manufacturing a micro LED according to an embodiment of the present invention.
4A is a flow chart for explaining each process of the epi layer deposition step in the micro LED manufacturing method according to an embodiment of the present invention, and FIG. 4B is a flow chart for explaining each process of the buffer layer deposition step among the epi layer deposition steps. .
5 illustrates each process of a buffer layer deposition step in a method of manufacturing a micro LED according to an embodiment of the present invention.
6 is a diagram illustrating a state in which an optical lithography process is performed in a unit LED chip forming step in a method of manufacturing a micro LED according to an embodiment of the present invention.
7 is a diagram illustrating each process of forming a unit LED chip in a manufacturing process of a side-type micro LED structure in a method of manufacturing a micro LED according to an embodiment of the present invention.
8 is a diagram illustrating each process of forming a unit LED chip in a process of manufacturing a vertical micro LED structure in a method of manufacturing a micro LED according to an embodiment of the present invention.
9 is a plan view showing a state in which a plurality of unit LED chips are disposed in a method of manufacturing a micro LED according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to constituent elements in each drawing, it should be noted that the same constituent elements are given the same reference numerals as much as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the subject matter of the present invention, a detailed description thereof will be omitted.

In describing the components of the embodiment according to the present invention, reference numerals such as first, second, i), ii), a), b) may be used. These codes are only for distinguishing the constituent elements from other constituent elements, and the nature, order, or order of the constituent elements are not limited by the symbols. In the specification, when a part'includes' or'includes' a certain element, it means that other elements may be further included rather than excluding other elements unless explicitly stated to the contrary. .

2 is a front cross-sectional view illustrating a state in which a dislocation (DL) is formed on the epi layer 200 and a dislocation growth prevention region in the method of manufacturing a micro LED according to an exemplary embodiment of the present invention.

Specifically, FIG. 2 shows a state in which the epi layer 200 is formed on the growth substrate 100 and a potential is formed on the epi layer 200 during the process of the micro LED manufacturing method according to an embodiment of the present invention. It is a front sectional view.

Referring to FIG. 2, a method of manufacturing a micro LED according to an embodiment of the present invention is performed by growing an epitaxial layer 200 having a plurality of layers on a growth substrate 100. In this case, the epitaxial layer 200 includes a plurality of layers, and the plurality of layers includes a buffer layer 210, a first conductivity type semiconductor layer, an active layer 230 and a second conductivity type semiconductor layer 240.

In addition, the epi layer 200 includes a dislocation growth prevention mask 300 for preventing dislocation growth in the epi layer 200, and at this time, the dislocation growth prevention mask 300 may be exemplarily located in the buffer layer 210. have.

At this time, since the dislocation growth prevention mask 300 is disposed at an appropriate position in the buffer layer 210, it is possible to prevent dislocation from growing in the dislocation growth prevention region D ₁ on the epi layer 200 as will be described in detail later. have.

As described above, in the micro LED manufacturing method according to an embodiment of the present invention, when the epitaxial layer 200 is grown in the manufacturing process, the area where dislocation growth is prevented from the area where dislocation growth is prevented is spatially separated by using the dislocation growth prevention mask 300 I did.

Further, at this time, the dislocation growth prevention region may be a region corresponding to a region in which each micro LED chip is formed.

Accordingly, in the micro LED of the present invention, by preventing potentials from being included in the epi layer 200 of the completed LED chip, effective charge transfer within the p-n junction of the epi layer 200 is possible.

In addition, due to this, the micro LED of the present invention has excellent electrical and optical properties, thereby contributing to solving the problem of defects occurring during the growth of the epi layer 200 in the conventional LED manufacturing process and the resulting light wavelength unevenness from the LED. I can.

3 is a flow chart showing each step of a method of manufacturing a micro LED according to an embodiment of the present invention.

Referring to FIG. 3, a method of manufacturing a micro LED according to an embodiment of the present invention includes a growth substrate arrangement step (S1), an epi layer deposition step (S2), and a unit LED chip formation step (S3).

In the growth substrate arranging step (S1), the growth substrate 100, which is a base layer for growing the epitaxial layer 200 of the micro LED according to an embodiment of the present invention, is disposed.

At this time, the growth substrate 100 may be, for example, a sapphire (Al ₂ O ₃ ) substrate, but unlike this, it may be a substrate made of other materials such as silicon, SiC, GaAs, and MgO.

In the epi layer deposition step (S2), a process of growing the epi layer 200 on the growth substrate 100 is performed. In this case, the growth of the epi layer 200 may be a process of sequentially depositing the buffer layer 210, the first conductive semiconductor layer 220, the active layer 230, and the second conductive semiconductor layer 240.

In this case, the first conductive semiconductor layer 220 and the second conductive semiconductor layer 240 are layers having opposite conductivity.

For example, when the first conductive semiconductor layer 220 has n-type conductivity, the second conductive semiconductor layer 240 has p-type conductivity. In this case, the first conductivity type semiconductor layer 220 may be an n-GaN layer having a group 4 element as an impurity, and the second conductivity type semiconductor layer 240 may be a p-GaN layer having a group 2 element as an impurity. have.

In the unit LED chip forming step (S3), a unit LED chip is formed by separating the layered structure in which the epi layer 200 is deposited on the growth substrate 100 by mesa etching and processing, and separating each unit LED chip. On the other hand, at this time, the area in which the unit LED chip is formed becomes the area in which the electric potential is minimized among the epi layer 200.

Figure 4a is a flow chart for explaining each process of the epi layer deposition step (S2) in the micro LED manufacturing method according to an embodiment of the present invention, Figure 4b is a buffer layer deposition step (S21) of the epi layer deposition step (S2) This is a flow chart for explaining each process.

In addition, Figure 5 shows each process of the buffer layer 210 deposition step in the micro LED manufacturing method according to an embodiment of the present invention.

Hereinafter, a process of the epi layer deposition step (S2) of the method for manufacturing a micro LED according to an embodiment of the present invention will be described in detail with reference to FIGS. 4 and 5, particularly, the process of the buffer layer deposition step (S21).

4A, in the method of manufacturing a micro LED according to an embodiment of the present invention, the epi layer deposition step (S2) includes a buffer layer deposition step (S21), a first conductive semiconductor layer deposition step (S22), and an active layer forming step ( S23) and a second conductive semiconductor layer deposition step (S24).

In the buffer layer deposition step (S21), in order to mitigate the decrease in the nucleation density due to the mismatch of the lattice constant between the growth substrate 100 and the first conductive semiconductor layer 220, the buffer layer 210 serving as a buffer layer is formed on the growth substrate ( 100). In this case, the buffer layer 210 may be, for example, an undoped GaN layer, but may have other configurations such as an AIN layer.

In the buffer layer deposition step (S21), a potential is formed and grown in the buffer layer 210. In the method of manufacturing a micro LED according to an embodiment of the present invention, as will be described in detail later, potential growth in the process of depositing the buffer layer 210 The prevention mask 300 was disposed to prevent deterioration of the micro LED quality due to the formation of dislocations.

Referring to Figure 4b, in the epi layer deposition step (S2) of the micro LED manufacturing method according to an embodiment of the present invention, the buffer layer deposition step (S21) includes a first vertical potential growth step (S211), a horizontal potential growth step (S212). ) And a second vertical potential growth step (S213).

In this case, the first vertical potential growth step S211 is a step in which a potential formed on the buffer layer 210 when the buffer layer 210 is grown is grown in a direction perpendicular to the interface between the growth substrate 100 and the buffer layer 210.

5A, the buffer layer 210 is grown on the growth substrate 100 in the initial stage of the buffer layer deposition step (S21), that is, the first vertical potential growth step (S211), and the growth substrate 100 on the buffer layer 210 It can be seen that the first vertical potential is formed in a direction perpendicular to the interface between the buffer layer 210 and the buffer layer 210.

At this time, an environment such as a growth rate, pressure, and temperature of the buffer layer 210 may be appropriately set so that the potential formed on the buffer layer 210 grows in a direction perpendicular to the interface between the growth substrate 100 and the buffer layer 210.

Meanwhile, as shown in FIG. 5B, a dislocation growth prevention mask 300 is disposed on the buffer layer 210 while the first vertical dislocation growth step S211 is in progress. At this time, the dislocation growth prevention mask 300 may be, for example, a SiO ₂ substrate, but may be made of a different material.

At this time, the dislocation growth prevention mask 300 is disposed in consideration of the dislocation growth prevention region, and in this case, the dislocation growth prevention region may be set in consideration of the arrangement of the unit LED chips later.

Meanwhile, in FIG. 5B, a configuration in which the dislocation growth prevention mask 300 is disposed after the buffer layer 210 is grown on the growth substrate 100 is shown, but unlike this, the dislocation growth prevention mask 300 is formed before the buffer layer 210 is grown. ) May be disposed on the growth substrate 100 and then the first vertical potential growth step S211 may be performed.

In addition, as shown in FIG. 5B, after disposing the dislocation growth prevention mask 300 on the buffer layer 210, the dislocation formed in the region corresponding to the dislocation growth prevention mask 300 stops further The epitaxial layer 200 on the growth prevention mask 300 may be formed with high quality.

At this time, it can be seen that vertical growth of dislocations continues in an area other than the area in which the dislocation growth prevention mask 300 is disposed.

Referring to FIG. 5C, the growth of the buffer layer 210 continues even after the dislocation growth prevention mask 300 is disposed, and a horizontal dislocation growth step S212 may be performed.

In this case, when the dislocation in the area around the dislocation growth prevention mask 300 is formed higher than the dislocation growth prevention mask 300, dislocation growth occurs at the interface between the buffer layer 210 and the growth substrate 100 or the dislocation growth prevention mask 300. ) Is placed in a horizontal direction.

This may be possible by changing growth conditions of the buffer layer 210 such as growth temperature and pressure.

In FIG. 5C, it is shown that only the dislocations closest to the dislocation growth prevention mask 300 are horizontally grown. However, unlike in FIG. 5C, not only the dislocations most adjacent to the dislocation growth prevention mask 300 but also other dislocation components may be horizontally grown. I can.

Meanwhile, each of the dislocations grown horizontally from both sides of the dislocation growth prevention mask 300 meets in the central region of the mask, and grows in a direction perpendicular to the interface between the buffer layer 210 and the growth substrate 100 in the central region of the mask. Will start.

Accordingly, a second vertical potential growth step S213 in which a second vertical potential grows perpendicular to the interface between the buffer layer 210 and the growth substrate 100 in the upper region of the center of the mask may be performed.

Referring to FIG. 5D, in the second vertical potential growth step S213, the second vertical potential is grown until the buffer layer 210 is completely grown.

In addition, even after complete growth of the buffer layer 210, the first conductive type semiconductor layer deposition step (S22), the active layer formation step (S23), and the second conductive type semiconductor layer deposition step (S24) proceed, and the buffer layer deposition step (S21). The potentials grown in may grow not only the buffer layer 210 but also the first conductive type semiconductor layer 220, the active layer 230, and the second conductive type semiconductor layer 240.

At this time, the second vertical potential is grown by avoiding the dislocation growth prevention area, which is an area where dislocations are not desired to be formed in the epi layer 200, and the density of dislocations formed therefrom is significantly reduced in the area where the unit LED chip will be formed later. do.

6 illustrates a state in which an optical lithography process is performed in the unit LED chip forming step (S3) of the micro LED manufacturing method according to an embodiment of the present invention.

Referring to FIG. 6, in a state where the epi layer deposition step (S2) is all completed, a patterned mask and photoresist (PR) are used on the top of the epi layer 200 through a known photolithography process. The area where the unit LED chip will be formed is divided.

At this time, the photoresist PR disposed on the epi layer 200 corresponds to the area where the unit LED chip or the electrode of the unit LED chip will be formed, and the photoresist PR is photosensitive in the subsequent etching process. Only the area except for can be etched.

At this time, as shown in FIG. 6, dislocations are densely formed in regions where the photoresist PR is not exposed, and dislocations are relatively small in the regions where photoresist PR is sensitized.

Accordingly, a region having a very small potential among the formed epitaxial layer 200 can be used as an LED chip, and thus, there is an advantage of producing a high-quality LED chip.

7 is a diagram illustrating each process of a unit LED chip forming step in a manufacturing process of a lateral micro LED structure in a method of manufacturing a micro LED according to an embodiment of the present invention, and FIG. 8 is an embodiment of the present invention. It shows each process of the unit LED chip forming step (S3) of the manufacturing process of the vertical micro LED structure of the micro LED manufacturing method according to the following.

Hereinafter, a process of forming an individual LED chip after a photolithography process in a method of manufacturing a micro LED according to an embodiment of the present invention will be described with reference to FIGS. 7 and 8.

First, referring to FIG. 7, mesa etching is performed on a deposition structure in a state in which the photolithography process shown in FIG. 6 is performed in order to manufacture a side-type micro LED.

At this time, as shown in FIG. 7A, portions of the epi layer 200 except for the area on which the photoresist is disposed are selectively etched. In this case, the area on which the photoresist is disposed is the dislocation growth prevention mask 300 of the epi layer 200. It may be a region corresponding to the dislocation growth prevention region in which dislocation formation is suppressed by ).

Thereafter, as shown in FIG. 7B, a first electrode (p electrode) and a second electrode (n electrode) are attached on the epi layer 200, and the regions in which the first and second electrodes are formed are separated by a separate adhesive ( Attach on blue tape; 500).

In addition, the growth substrate 100, the mask, and the buffer layer 210 are removed from the combination of the growth substrate 100 and the epi layer 200 attached to the adhesive 500, as shown in FIG. 7C. Thereafter, the adhesive 500 is removed, and individual LED chips are separated for each unit area.

Meanwhile, referring to FIG. 8, in order to manufacture a vertical micro LED, mesa etching is performed on a deposition structure in a state in which the photolithography process shown in FIG. 6 is performed.

In this case, as shown in FIG. 8A, portions of the epitaxial layer 200 excluding a region in which the photoresist is disposed are selectively etched. In this case, the region in which the photoresist is disposed may be a region corresponding to the dislocation growth prevention region.

Thereafter, as shown in FIG. 8B, a first electrode (p electrode) is attached on the epi layer 200 and transferred to the receiving substrate 600 through an LLO process or the like.

Thereafter, as shown in FIG. 8C, the growth substrate 100 and the buffer layer 210 are removed by etching, and a second electrode (n electrode) is attached on the second conductive semiconductor layer 240. After that, separate LED chips for each unit area.

On the other hand, at this time, as shown in FIGS. 7 and 8, it can be seen that little or no potential is formed on the region of the epi layer 200 that functions as an electrical function in the individual LEDs that are finally separated.

9 is a plan view showing a state in which a plurality of unit LED chips are disposed in a method of manufacturing a micro LED according to an embodiment of the present invention.

Referring to FIG. 9, it can be seen that a region in which a unit LED chip in which a micro LED is to be disposed is formed on the growth substrate 100 is divided.

At this time, the cluster of each unit LED chip area may be arranged in a stripe shape formed in two rows as shown in FIG. 9A, for example, and as shown in FIG. 9B, the four unit LED chip areas form one cluster. It can also be arranged in a shape.

At this time, the arrangement of the unit LED chip region may be differently formed, but regardless of the shape of the arrangement of the unit LED chip region, the unit LED region is in a region outside the region in which a potential is formed on the epi layer 200. Is set to be located.

Therefore, it is possible to effectively reduce the potential existing in the epitaxial layer 200 of the individual LEDs finally manufactured, thereby making it possible to uniformly form the degree of light emission of each LED in the LED manufacturing process, and significantly reduce the occurrence rate of defective LEDs. Can be reduced.

On the other hand, the method of reducing the formation of dislocations on the epitaxial layer 200 of the micro LED using the dislocation growth prevention mask 300 in the micro LED manufacturing method of the present invention is of particular technical significance in that the subject of the present invention is particularly micro LED. Can have

In the case of a conventional LED, the size of the LED element itself is formed considerably larger than that of the micro LED, and the size of the dislocation growth prevention mask 300 should be limited to a certain size or less when considering the growth conditions of the epi layer 200. There is a limit to that.

Therefore, in the case of a conventional LED having a relatively large size, not a micro LED, there is a limitation that the size of the potential growth prevention mask 300 is inevitably formed smaller than the size of the LED element.

However, since the micro LED manufacturing method according to an embodiment of the present invention can be mainly performed on a micro LED whose size is as small as several tens of μm, in the case of the micro LED according to an embodiment of the present invention, the size of the micro LED device itself May be formed smaller than the dislocation growth prevention mask 300.

For this reason, according to the method of manufacturing a micro LED according to an embodiment of the present invention, the dislocation growth prevention mask 300 is appropriately disposed in the epi layer 200 and the micro LED device at an appropriate position corresponding to the dislocation growth prevention mask 300 It is possible to minimize the adverse effect that the potential may have on the micro LED device by adjusting to form.

The above description is merely illustrative of the technical idea of the present embodiment, and those of ordinary skill in the technical field to which the present embodiment belongs will be able to make various modifications and variations without departing from the essential characteristics of the present embodiment. Accordingly, the present exemplary embodiments are not intended to limit the technical idea of the present exemplary embodiment, but are illustrative, and the scope of the technical idea of the present exemplary embodiment is not limited by these exemplary embodiments. The scope of protection of this embodiment should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present embodiment.

100: growth substrate
200: epi layer
300: dislocation growth prevention mask
400: electrode
500: adhesive
600: receiving substrate

Claims (11)

Arranging the growth substrate;
Depositing an epitaxial layer composed of a plurality of layers on the growth substrate;
Separating the epitaxial layer and forming a unit LED chip,
In the step of depositing the epi layer, disposing a potential growth prevention mask in a region in the epi layer corresponding to a region in which the unit LED chip is to be formed so as to prevent the potential formed on the epi layer from reaching the unit LED chip. Carry out the process,
Micro LED manufacturing method, characterized in that the width of the dislocation growth prevention mask is greater than the width of the unit LED chip. The method of claim 1,
The step of depositing the epi layer
Depositing a buffer layer on the growth substrate;
Depositing a first conductive type semiconductor layer on the buffer layer;
Forming an active layer on the first conductive semiconductor layer; And,
And depositing a second conductive type semiconductor layer on the active layer,
And disposing the dislocation growth prevention mask in a region in the buffer layer corresponding to a region in which the unit LED chip is to be formed in the step of depositing the buffer layer. The method of claim 2,
The step of depositing the buffer layer,
A first vertical potential growth step of depositing the buffer layer so that the potential formed in the buffer layer grows in a direction perpendicular to an interface between the growth substrate and the buffer layer;
A horizontal potential growth step of depositing the buffer layer so that the potential formed on the buffer layer grows in a direction horizontal to an interface between the growth substrate and the buffer layer; And,
A second vertical deposition of the buffer layer such that a plurality of dislocations grown in the horizontal dislocation growth step are connected and combined, and a bonding dislocation formed by combining the plurality of dislocations grows in a direction perpendicular to an interface between the growth substrate and the buffer layer. Dislocation growth stage
Micro LED manufacturing method comprising a. The method of claim 3,
The coupling potential is formed in a direction perpendicular to the boundary surface of the buffer layer and the growth substrate in a central upper region of the potential growth prevention mask among the buffer layers, and the unit LED chip is divided into a plurality of regions where the coupling potential is formed. Micro LED manufacturing method, characterized in that the dog is arranged. The method of claim 4,
A method of manufacturing a micro LED, characterized in that the plurality of unit LED chips are arranged to form heat by being separated by a boundary in the region where the coupling potential is formed. The method of claim 4,
A method of manufacturing a micro LED, characterized in that the plurality of LED chips are separated by a boundary in which the coupling potential is formed, so that four unit LED chips are arranged to form a square shape. The method of claim 2,
The buffer layer is a method of manufacturing a micro LED, characterized in that the undoped GaN (Galium Nitride) layer. In claim 1,
The light emitting diode is a micro LED manufacturing method, characterized in that the side-type LED structure (Lateral type). In claim 1,
The light emitting diode is a micro LED manufacturing method, characterized in that the vertical type LED structure (Vertical type). In claim 1,
The dislocation growth prevention mask is a micro LED manufacturing method, characterized in that made of SiO ₂ . Micro LED manufactured by the micro LED manufacturing method of claim 1.

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