KR20180103624A - micro LED module and method for making the same - Google Patents

Abstract

Disclosed is a manufacturing method of a micro LED module capable of solving a misalignment problem. The manufacturing method comprises the following steps: preparing a micro LED including a plurality of electrode pads and a plurality of LED cells; preparing a submount substrate including a plurality of electrodes corresponding to the electrode pads; and performing flip bonding the micro LED to the submount substrate using a plurality of solders positioned between the electrode pads and the electrodes. The step of performing flip bonding includes heating the solders with a laser beam.

Description

[0001] The present invention relates to a micro-LED module and a manufacturing method thereof,

The present invention relates to a method of manufacturing a micro-LED module by flip-bonding a micro-LED including a light-transmitting substrate having a large difference in thermal expansion coefficient from the sub-mount substrate on a sub-mount substrate.

A display device using a micro-LED module is known. A micro-LED module is manufactured by flip-bonding a micro-LED including a plurality of LED cells on a sub-mount substrate.

Typically, the micro-LED includes a light-transmitting sapphire substrate and a gallium nitride-based semiconductor light-emitting portion formed on the light-transmitting sapphire substrate and having a plurality of LED cells. The semiconductor light emitting portion includes an n-type semiconductor layer exposed region formed by etching, and the plurality of LED cells are formed in a matrix array on the n-type semiconductor layer exposed region. Each LED cell includes an n-type semiconductor layer, an active layer and a p-type conductivity-type semiconductor layer, and a p-type electrode pad is formed in the p-type conductivity-type semiconductor layer of each LED cell. An n-type electrode pad is formed in the n-type semiconductor layer exposed region.

On the other hand, the submount substrate includes a plurality of electrodes corresponding to the electrode pads of the micro-LED. By flip-bonding the micro-LED to the mound substrate using the solder bumps, the electrode pads of the micro-LED are connected to the electrodes of the sub-mount substrate. In order to flip-bond the micro-LED to the sub-mount substrate, the solder constituting at least a part of the solder bump must be heated to a temperature near the melting point. Since the difference between the thermal expansion coefficient of the Si-based submount substrate and the thermal expansion coefficient of the sapphire substrate is large, there is a large difference between the expansion amount and the shrinkage deformation amount between the Si submount substrate and the sapphire substrate during heating and cooling in the flip bonding process This difference causes a serious misalignment between the submount substrate and the micro-LED. Such misalignment results in failure of the electrode pads of the micro-LEDs and the electrodes of the submount substrate to be connected, or more seriously, to improper connection, resulting in serious defects such as short-circuiting.

For example, the thermal expansion coefficient of the sapphire substrate on which the micro-LED is based is 7.6 占 퐉 m-1K and the thermal expansion coefficient of the Si-based submount substrate is 2.6 占 퐉 m-1K. Which is approximately 2.5 times the thermal expansion coefficient of the mount substrate. When the solder having a high melting point of the bump used for the flip bonding is used, the bonding temperature becomes high. In this case, misalignment may occur between the micro-LED and the sub-mount substrate due to a serious difference in the thermal expansion coefficient. For example, if the melting point temperature of the solder at 260 캜 is set to the bonding temperature, misalignment of about 5 to 6 μm is generated on the basis of 1 cm substrate, which is practically difficult to use in a process requiring 2um bonding precision like flip bonding of micro-LEDs.

Accordingly, there is a need in the art to solve the misalignment problem due to the difference in thermal expansion coefficient between the micro-LED-side sapphire substrate and the sub-mount substrate in flip-bonding the micro-LED and the sub-mount substrate.

Korean Registered Patent No. 10-1150861 (Registered May 22, 2012) Korean Registered Patent No. 10-0470904 (Registered on January 31, 2005)

A problem to be solved by the present invention is to locally heat a solder positioned between a micro-LED and a sub-mount substrate to locally heat the micro-LED and the sub-mount substrate to prevent a high temperature from being heated, And to provide a method of manufacturing a micro-LED module capable of solving the problem of misalignment caused by the micro-LED module.

According to an aspect of the present invention, there is provided a method of manufacturing a micro-LED module, comprising: preparing a micro-LED including a plurality of electrode pads and a plurality of LED cells; Preparing a submount substrate including a plurality of electrodes corresponding to the plurality of electrode pads; And flip-bonding the micro-LED to the sub-mount substrate using a plurality of electrode pads and a plurality of solders positioned between the plurality of electrodes, wherein the flip- And heating with a laser beam.

According to one embodiment, the flip bonding step includes locally heating each of the plurality of solders with a plurality of laser beams.

According to an embodiment of the present invention, individual electrode pads are formed in each of the LED cells, and the flip bonding is performed between the individual electrode pads and the submount substrate with a laser beam passing through the LED cell and the individual electrode pads, Lt; RTI ID = 0.0 > solder < / RTI >

According to one embodiment, the individual electrode pads are laser beam transmissive.

According to one embodiment, the individual electrode pads include cavities through which the laser beam passes.

According to an embodiment of the present invention, the micro-LED includes a common electrode pad on the surface of the plurality of LED cell peripheral epitaxial layers, and the flip- The solder positioned between the electrode pad and the submount substrate is heated.

According to one embodiment, the common electrode pad has laser beam transmissivity.

According to one embodiment, the common electrode pad includes a cavity through which the laser beam passes.

According to one embodiment, the flip bonding step may heat the plurality of solders with a plurality of laser beams passing vertically through the micro-LED from one side of the micro-LED to the other side of the micro-LED, The beam includes a substrate, a laser beam passing through the epi layer without the LED cell, and a laser beam passing through the substrate and the epi layer with the LED cell.

According to one embodiment, the flip bonding step may include heating the plurality of solders with a plurality of laser beams vertically passing through the micro-LEDs from one side of the micro-LED to the other side of the micro-LED, And a focusing lens is used to focus each of the solder.

According to one embodiment, the flip bonding step further comprises: for heating the plurality of solders with a plurality of laser beams passing vertically through the micro-LED from one side of the micro-LED to the other side of the micro-LED, And arranging a plurality of laser beam irradiation units on one side of the micro-LED in an array corresponding to the arrangement of the solder.

According to one embodiment, in order to heat the plurality of solders with a plurality of laser beams passing vertically through the micro-LEDs from one side of the micro-LED to the other side of the micro-LED, an array corresponding to the array of the plurality of micro- A plurality of laser beam irradiating units are arranged on one side of the micro-LED, wherein the plurality of laser beam irradiating units include an optical guide connected to the laser light source, a collimator for converting the laser beam passed through the optical guide into a parallel beam, A beam adjuster for adjusting a cross-sectional size of the laser beam made of a parallel beam, and a focusing lens for focusing the adjusted laser beam on each of the solder.

According to one embodiment, the flip bonding step may include matching a plurality of laser beam irradiating units with a plurality of solders at a ratio of 1: 1, and heating each of the plurality of solders with the laser beam irradiated by each of the plurality of laser beam irradiating units .

According to one embodiment, the flip bonding step may be performed by matching one laser beam irradiating unit with two or more solders by 1: n (n is a natural number of 2 or more), and moving the laser beam irradiating unit in a linear or zigzag manner , The two or more solders can be heated by the laser beam irradiated by the laser beam irradiation unit.

According to one embodiment, the flip bonding step may match two or more laser beam irradiating units to each of two or more solder groups, and each of the laser beam irradiating units may heat the solders in each solder group.

According to another aspect of the present invention, there is provided a micro-LED module including a substrate and an epi layer, wherein a plurality of LED cells are formed in the epi layer, and each of the plurality of LED cells includes a second And a plurality of common electrode pads of a first conductivity type are formed around the plurality of LED cells; A submount substrate on which the individual electrode pads and the plurality of electrodes corresponding to the common electrode pads are formed; And a solder positioned between the electrode and the individual electrode pad or the common electrode pad. The solder is heated by a laser beam and cured to connect the electrode to the individual electrode pad or the common electrode pad.

According to one embodiment, the substrate, the epilayer, the individual electrode pad, and the common electrode pad are arranged such that the laser beam irradiates the laser beam so that the laser beam can heat the solder through one side of the micro- As shown in FIG.

According to one embodiment, the individual electrode pads may be formed of a material that transmits the laser beam.

According to one embodiment, the individual electrode pads may include a cavity through which the laser beam passes.

According to one embodiment, the common electrode pad may be formed of a material that transmits the laser beam.

According to one embodiment, the common electrode pad may include a cavity through which the laser beam passes.

According to the present invention, a laser is locally irradiated to each of a plurality of solders located between a microdrive and a submount substrate, and the solder is melted rapidly, so that a micro-LED having laser permeability and a submount substrate So that it is possible to solve the misalignment problem due to the difference in thermal expansion coefficient between the micro-LED and the sub-mount substrate.

1A to 1E are views for explaining a process of manufacturing a micro-LED.
2 is a cross-sectional view showing a part of the submount substrate.
Figs. 3 and 4 are views for explaining a step of forming a bump including a solder on a submount substrate. Fig.
FIGS. 5A, 5B, and 5C are views for explaining a process of flip-bonding a micro-LED and a sub-mount substrate.
6 is a view for explaining another embodiment of the present invention.
7 and 8 are views for explaining another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. It is to be understood that both the foregoing description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. Accordingly, the drawings and embodiments are to be considered as illustrative and not restrictive, No, it will be.

According to an embodiment of the present invention, there is provided a method of manufacturing a micro-LED module by flip-bonding a micro-LED to a sub-mount substrate which is an active matrix substrate. A method of fabricating a micro-LED module according to an embodiment of the present invention is performed after a step of preparing an Si-based submount substrate in which an electric circuit and electrodes are formed in advance, and a step of fabricating a micro-LED based on a sapphire substrate.

Hereinafter, micro-LED fabrication, bump formation, flip bonding of a micro-LED and a sub-mount substrate will be described in order.

Micro LED production (preparation)

1A to 1E, a process of fabricating a micro LED will be described.

First, as shown in FIG. 1A, an n-type semiconductor layer 132, an active layer 133, and a p-type semiconductor layer 132 are formed on a primary surface of a transparent sapphire substrate 131 having a thermal expansion coefficient of 7.6 m- An epitaxial layer including a hole 134 is formed.

Next, as shown in FIG. 1B, ditches 101 for etching the epi layer to a predetermined depth using a mask pattern to separate the LED cells 130, and at least the outer peripheries of the LED cells 130 Type semiconductor layer 132. The active layer 133 and the p-type semiconductor layer 134 are formed on the n-type semiconductor layer 132, (130) are formed. Although not shown, a buffer layer may be formed between the n-type semiconductor layer 132 and the sapphire substrate 131. The active layer 133 and the p-type semiconductor layer 134 and the exposed surface of the p-type semiconductor layer 134 perform certain functions Other semiconductor layers may be interposed. Since the epi layer including the n-type semiconductor layer 132, the active layer 133 and the p-type semiconductor layer 134 and the sapphire substrate 131 have laser permeability, the LED cell 130 also has laser transmittance.

1C, a laser-transmissive p-type electrode pad 150 is formed on the p-type semiconductor layer 134 of each of the LED cells 130, and an exposed region of the n-type semiconductor layer 132 Transmissive n-type electrode pad 140 is also formed in the outermost region. The step difference between the p-type semiconductor layer 134 and the n-type semiconductor layer 132 is compensated for by making the thickness of the p-type electrode pad 150 and the n-type electrode pad 140 different from each other, -Type electrode pad 150 and the solder-bonding surface of the n-type electrode pad 140 may be substantially flush with each other.

Next, as shown in FIG. 1D, a passivation layer 160 is formed to cover both the LED cells 130 and the exposed region 102 of the n-type semiconductor layer 132.

Next, as shown in FIG. 1E, a first pad exposure hole 162 for exposing the p-type electrode pad 150 and a second pad exposure hole 164 for exposing the n-type electrode pad 140 are formed. . The first pad exposure hole 162 and the second pad exposure hole 164 may be formed by etching using a mask pattern. In this embodiment, the passivation layer 160 is formed to have a substantially constant thickness along the cross-sectional profile of the LED cells 130 to reduce the width and the depth of the valleys 101 between neighboring LED cells 130 , So that the goal remains unchanged. However, the passive layer 160 may be formed to completely fill the trough 101.

Submount board preparation and bump formation

Referring to FIG. 2, before the pillar bump forming step, a Si-based submount substrate 200 having a size of about 15,000 μm to 10,000 μm and CMOS cells corresponding to LED cells is prepared. The submount substrate 200 includes a plurality of CMOS cells corresponding to the plurality of LED cells, a plurality of discrete electrodes 240 corresponding to the p-type electrode pads of the micro-LED, And a common electrode (not shown) corresponding to the pad. The submount substrate 200 includes a plurality of electrodes 240 formed in a matrix array on the Si-based substrate base material 201 and connected to the CMOS cells, a passivation layer 250 formed to cover the electrodes 240, And electrode exposure holes 252 are formed in the passivation layer 250 to expose the individual electrodes 240.

3 and 4, the process of forming the bumps includes a first cleaning step S101, an under bump metallurgy forming step S102, a photolithography step S103, a scum removing step S104, The copper plating step S105, the solder metal plating step S106, the PR removing step S107, the UBM etching step S108, the second cleaning step S109, the reflow step S110, (S111).

In the first cleaning step (S101), the submount substrate 200 introduced as shown in FIG. 4A is cleaned by using a scrubber. The submount substrate 200 includes a pad-shaped electrode 240 formed of Al or Cu material on a substrate base material 201 on which a CMOS cell is formed by a CMOS process and an electrode exposing hole 240 exposing a region of the electrode 240. [ And a passivation layer 250 formed on the substrate base material 201 with a first passivation layer 252 therebetween.

4B, the UBM forming step S102 is a step of forming a UBM 261 for enhancing the adhesion between the electrode 240 and the Cu pillars and preventing the solder from diffusing into the passive layer 250 And on the sub-mount substrate 200 so as to cover the electrode 240. In this embodiment, the UBM 261 is formed of a Ti / Cu laminated structure and can be formed by sputtering the metal.

The photolithography step 103 is a step of forming a photosensitive PR (photoresist) 300 so as to entirely cover the UBM 261 on the submount substrate 200, as shown in FIG. 4C, An electrode exposure hole 302 for exposing only one region of the UBM 261 immediately above the electrode 240 is formed by placing a pattern (not shown) and irradiating light. Next, a scum removing step (S104) for removing the scum generated during the photolithography step is performed.

Next, a Cu plating step (S105) and a solder metal plating step (S106) are performed one after another to form an opening (302) of the PR (300), as shown in Cu is plated to form a Cu pillar 262. SnAg is plated on the Cu pillar 262 as a solder metal to form a SnAg solder cap 263 in a layer having a certain thickness. Note that in this specification, Cu may be Cu alloy containing Cu or Cu.

Next, the PR removing step S107 is performed to expose the upper surface and the side surface of the bump including the Cu pillar 262 and the solder 263, as shown in Fig. 4 (e).

Next, the UBM etching step S108 is performed to remove the remaining UBM except for the UBM 261 located under the Cu pillar 262 by etching, as shown in Fig. 4 (f). Then, a second cleaning step (S109) for removing the residue is performed. After the UBM etching step S109, a bump 260 in which a Cu pillar 262 and a solder cap 263 are sequentially stacked is formed on the UBM 261 on the electrode 240 of the submount substrate 200. Next, a reflow step (S110) is carried out so that the layered solder 263 is melted and solidified to form a hemispherical or semicircular cross-sectional shape. Rapid Thermal Processing (RTP) can be usefully used. Then, a third cleaning step (S111) for removing the residue again is performed after the reflow step (S110).

The interval between the Cu pillar bumps 260 on the submount substrate 200 is preferably approximately the same as the diameter of the Cu pillar 262 and the interval between the Cu pillar bumps 260 should not exceed 5 μm. If the interval between the Cu pillar bumps 260 is more than 5 μm, the diameter of the Cu pillar bumps 260 and the size of the corresponding LED cell must be increased. As a result, the precision of the display device including the micro-LED can be reduced.

Flip Bonding

Referring to FIGS. 5A and 5B and 5C, a submount substrate 200 based on a Si substrate base material having a thermal expansion coefficient of 2.6 탆 m-1K has a coefficient of thermal expansion of about 7.6 탆 flip bonding between the micro-LEDs 100 based on the sapphire substrate 131 having a thermal expansion coefficient of m-1K is performed.

As described above, the submount substrate 200 includes a plurality of electrodes corresponding to the electrode pads 150 of the micro-LED 100, and each of the plurality of electrodes includes a Cu pillar 262 and a SnAg A bump 260 composed of solder (i.e., solder cap 263) is formed in advance. Each of the LED cells 130 and the electrode pads 150 and 140 of the microdevice 100 are electrically connected to the solder 263 by a laser beam for locally heating the solder 263, So that it has laser transmittance. For example, the electrode pads 150 and 140 are formed of a transparent metal compound material having conductivity, and transmit the laser beam.

The solder 263 formed on the pillar 262 is positioned between the electrode pads 150 and 140 of the micro LED 100 and the electrode of the submount substrate 200 and then solder 263 The electrode pads 150 and 140 of the micro-LED 100 and the electrodes of the sub-mount substrate 200 are bonded to each other.

In order to flip-bond the micro-LED 100 to the sub-mount substrate 200 using the laser, the individual electrode pads 150 provided in the LED cells 130 of the micro-LED 100 and the micro- Mount substrate 200 and the electrode pads 140 on the side of the micro-LED 100 in the state that the common electrode pad 140 formed on the outer area of the sub-mount substrate 200 faces the electrodes of the sub- It is necessary to position the bumps 260 that include the solder 263 or the solder 263 between each of them. Accordingly, a plurality of solders 263 are positioned between the micro-LEDs 110 and the submount substrate 100 in an arrangement corresponding to the arrangement of the plurality of electrode pads 150, 140.

Next, a plurality of laser beam irradiation units 1000 are arranged on the upper side of the micro LED 100 in the same arrangement as the array of a plurality of solders 263. Each laser beam irradiating unit 1000 includes an optical guide 1100 formed of an optical fiber connected to a laser light source, a collimator 1200 converting a laser beam passed through the optical guide 1100 into a parallel beam, A beam adjuster 1300 for adjusting the cross-sectional size of the beam, and a focusing lens 1400 for converging the laser beam adjusted by the beam adjuster 1300 at one point. Although not shown, the laser beam irradiation unit 1000 may further include a laser light amplifier, an optic coupler, a laser oscillation control unit, and the like. The output of the laser beam is appropriately selected to match the melting point of the solder material.

The laser beam L is supplied to the collimator 1200 through the optical guide 1100. The collimator 1200 outputs the laser beam as parallel light, The beam adjuster 1300 extends the diameter of the laser beam formed in the collimator shape through the collimator 1200. The converging lens 1400 passes the laser beam having the increased diameter through the micro-LED 100, 100 to the solder 263 in contact with the electrode pads 150, 140, respectively. As a result, the solder 263 is heated and melted by the laser beam L focused on each of the solders 263. Since the laser beam passes through the micro-LED 100 but passes through the micro-LED 100 in an unfocused state, the heating effect of the micro-LED 100 by the laser beam L is insignificant, And shrinkage does not occur. The solder 2963 rapidly heated by the laser beam L is cooled and cured so that the electrode pads 150 and 140 on the side of the micro-LED 100 by the solder 263 and the electrode on the side of the sub- Bonding is completed. The focusing position of the laser beam L is preferably set to 1/3 to 2/3 of the height of the solder before melting. The LED cell 130 and the electrode pads 150 and 140 may be damaged by heat when the focal position of the laser beam L is more than 2/3 of the height of the solder and is close to the side of the micro LED 100, When the focal position of the laser beam L is less than 1/3 of the height of the solder, there is a high possibility that the circuit on the submount substrate 200 is damaged by heat.

Other Embodiments

6A, the electrode pads 150 and 140 are formed of a material that is impermeable to the laser beam L, and the laser beams L are passed through the electrode pads 150 and 140, respectively, Cavities 152 and 142 may be formed. Each of the cavities 152 and 142 is in contact with the LED cell 130 of the laser diode 100 having the laser beam transmissivity and the solder 263 disposed between the submount substrate 200 and the micro- Respectively. When the laser irradiation unit 1000 operates, the laser beam L passing through the focusing lens 1400 passes through the micro-LED 100 and then passes through the cavities 152 and 142 of the electrode pads 150 and 140 And reaches the solder 263 and is focused on the solder 263. Thus, the solder 263 is melted and cured to connect the electrode pad on the micro-LED 100 and the electrode on the sub-mount substrate 200 (or the pillar formed on the electrode). The molten solder 263 fills the cavities 152 and 142, thereby enabling more reliable bonding.

In another embodiment

In the foregoing description of the embodiment, a plurality of laser beam irradiating units 1000 are matched to each of a plurality of solders at a ratio of 1: 1, and a plurality of laser beams L irradiated from each of the plurality of laser beam irradiating units 1000 are formed at a ratio of 1: 1 < / RTI > However, according to other embodiments of the present invention, as shown in FIG. 7, one laser beam irradiating unit 1000 can participate in heating of several solders L while moving in an arbitrary direction. That is, one laser beam irradiation unit 1000 can participate in two or more solder heating in a ratio of 1: n (n is a number of 2 or more).

Examples of the method of using a smaller number of laser beam irradiation units than the number of solders as described above include heating a plurality of solders 263 in a linear pattern line by line as shown in FIG. A plurality of solders 263 may be heated in a zigzag pattern or a plurality of laser beams L1, L2, L3 and L4 may be applied to several groups G1, G2, G3, and L4 as shown in FIGS. G4) may be heated by the group. In the case of group-by-group heating, heating through linear pattern movement of the laser beam irradiation unit as shown in (c) of FIG. 8, heating through zigzag pattern movement of the laser beam irradiation unit as shown in FIG. 8 (d) Heating through movement can be considered.

As described above, according to the present invention, a number of laser beam irradiating units are matched with a plurality of solders at a ratio of 1: 1, and each of the plurality of laser beam irradiating units is heated by a laser beam irradiated by each of the plurality of solders, (N is a natural number equal to or greater than 2) with one or more solders and moves the laser beam irradiating unit in a linear or zigzag manner, The laser beam irradiation unit may heat the two or more solders with a laser beam irradiated by the laser beam irradiation unit or may match two or more laser beam irradiation units to each of two or more solder groups, The flip bonding step can be performed by heating the solders in the group.

Particularly, the above-described flip bonding using the group-by-group heating is problematic in terms of economical efficiency and work space utilization, which is a problem of a method in which the laser beam and the solder are matched with each other at a ratio of 1: 1, The problem of the heating and cooling time problems can be compensated.

In the above description, the solder is heated by the laser beam passing through the micro-LED including the sapphire substrate. However, the laser beam transmissive submount substrate is used to irradiate the submount substrate with a laser beam, It is also possible to use a method of

100 .............................. Micro LED
130 .............................. LED cell
131 ...................... LED substrate (or sapphire substrate)
200 .............................. Submount substrate
1000 ...................... Laser irradiation unit

Claims (22)

Preparing a micro-LED including a plurality of electrode pads and a plurality of LED cells;
Preparing a submount substrate including a plurality of electrodes corresponding to the plurality of electrode pads; And
And flip-bonding the micro-LED to the submount substrate using a plurality of electrode pads and a plurality of solders positioned between the plurality of electrodes,
Wherein the flip bonding step comprises heating the plurality of solders with a laser beam. 2. The method of claim 1, wherein the flip bonding step locally heats each of the plurality of solders with a plurality of laser beams. The method of claim 1, wherein individual electrode pads are formed on each of the LED cells, wherein the flip bonding is performed by a laser beam sequentially passing through the LED cell and the individual electrode pads, Wherein the solder is heated to a predetermined temperature. 4. The method of claim 3, wherein the individual electrode pads are laser beam transmissive. 4. The method of claim 3, wherein the individual electrode pads include cavities through which a laser beam passes. The method of claim 1, wherein the micro-LED comprises a common electrode pad on a surface of the plurality of LED cells adjacent to the common electrode pad, wherein the flip-bonding step includes a laser beam passing through the common electrode pad, And the solder located between the pad and the submount substrate is heated. 7. The method of claim 6, wherein the common electrode pad has laser beam transmissivity. 7. The method of claim 6, wherein the common electrode pad includes a cavity through which a laser beam passes. The method of claim 1, wherein the flip bonding step comprises heating the plurality of solders with a plurality of laser beams vertically passing through the micro-LEDs from one side of the micro-LED to the other side of the micro-LED, Comprises a substrate, a laser beam passing through the epi layer without the LED cell, and a laser beam passing through the substrate and the epi layer with the LED cell. [2] The method of claim 1, wherein the flip bonding step comprises heating the plurality of solders with a plurality of laser beams vertically passing through the micro-LEDs from one side of the micro-LED to the other side of the micro- And a focusing lens is used so as to be focused on each of the solder. The method of claim 1, wherein the flip bonding comprises: heating the plurality of solders with a plurality of laser beams vertically passing through the micro-LED from one side of the micro-LED to the other side of the micro- Wherein a plurality of laser beam irradiating units are arranged on one side of the micro-LED in an array corresponding to the arrangement of the micro-LEDs. The method of claim 1, further comprising, in order to heat the plurality of solders with a plurality of laser beams passing vertically through the micro-LED from one side of the micro-LED to the other side of the micro-LED, And a plurality of laser beam irradiating units arranged on one side of the micro-LED, wherein the plurality of laser beam irradiating units include an optical guide connected to the laser light source, a collimator for converting the laser beam passed through the optical guide into a parallel beam, A beam adjuster for adjusting a size of a cross section of the laser beam; and a focusing lens for converging the laser beam adjusted on the beam adjuster to each of the solder. [2] The method of claim 1, wherein the flip bonding step comprises heating the plurality of solders with the plurality of laser beams by matching the plurality of solders with a plurality of laser beams at a ratio of 1: 1. [2] The method of claim 1, wherein the flip bonding step comprises heating the plurality of solders with a laser beam irradiated by each of the plurality of laser beam irradiating units by matching a plurality of laser beam irradiating units with a plurality of solders at a ratio of 1: Wherein the method comprises the steps of: [2] The method of claim 1, wherein the flip bonding comprises matching one laser beam irradiating unit with two or more solders by 1: n (n is a natural number of 2 or more), moving the laser beam irradiating unit linearly or zigzag , And the two or more solders are heated by the laser beam irradiated by the laser beam irradiating unit. The method of claim 1, wherein the flip bonding step comprises matching two or more laser beam irradiation units to each of two or more solder groups, and each of the laser beam irradiation units heats solders in each solder group Method of manufacturing a module. A plurality of LED cells are formed in the epitaxial layer, a plurality of individual electrode pads of a second conductivity type are formed in each of the plurality of LED cells, and a first conductive type A micro-LED having a common electrode pad;
A submount substrate on which the individual electrode pads and the plurality of electrodes corresponding to the common electrode pads are formed;
And a solder positioned between the electrode and the individual electrode pad or the common electrode pad,
Wherein the solder is heated by a laser beam and cured to connect the electrode to the individual electrode pad or the common electrode pad. [Claim 17] The method of claim 17, wherein the substrate, the epilayer, the individual electrode pad, and the common electrode pad are heated by a laser beam so that the laser beam can heat the solder through one side of the micro- The micro-LED module comprising: [19] The micro-LED module according to claim 17, wherein the individual electrode pads are formed of a material that transmits the laser beam. 18. The micro-LED module of claim 17, wherein the individual electrode pad comprises a cavity through which the laser beam passes. [18] The micro-LED module according to claim 17, wherein the common electrode pad is formed of a material that transmits the laser beam. 18. The micro-LED module of claim 17, wherein the common electrode pad includes a cavity through which the laser beam passes.

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