KR20200001329A - Micro led transfer system - Google Patents

Abstract

The present invention relates to a micro LED transfer system, which can more effectively transfer a micro LED by using vacuum absorptive power. The micro LED transfer system includes: a vacuum pump; an adsorption head adsorbing the micro LED with the vacuum absorptive power in accordance with operation of the vacuum pump; and a valve which is openable so that vacuum pressure applied to the adsorption head is equal to pressure of a transfer space.

Description

Micro LED Transfer System {MICRO LED TRANSFER SYSTEM}

The present invention relates to a micro LED transfer system for transferring a micro LED from a first substrate to a second substrate.

Currently, the display market is still the mainstream, while OLED is rapidly becoming the mainstream by replacing LCD. As display companies are participating in the OLED market rush, Micro LED (hereinafter referred to as “micro LED”) display is emerging as another next generation display. The key materials of LCD and OLED are liquid crystal and organic materials, respectively, whereas micro LED display is a display that uses micrometer (μm) LED chip itself as a light emitting material.

When Cree applied for a patent on "Micro-light Emitting Diode Arrays with Improved Light Extraction" in 1999 (Registration No. 0731673), the research and development has been published since the publication of the term micro LED. This is being done. The challenge to apply micro LEDs to displays requires the development of custom microchips based on flexible materials / devices for micro-LED devices, and the accuracy of transfer and display pixel electrodes of micrometer-sized LED chips. There is a need for technology for mounting.

In particular, with respect to the transfer of the micro LED device to the display substrate, as the LED size is reduced to the micrometer (μm) unit, the existing pick & place equipment can not be used, and more precisely There is a need for transfer head technology. In relation to the transfer head technology, several structures as described below have been proposed, but each proposed technology has some disadvantages.

Luxvue of the United States has proposed a method for transferring a micro LED using an electrostatic head (Public Patent Publication No. 2014-0112486, hereinafter referred to as "prior invention 1"). The transfer principle of the present invention 1 is a principle of generating adhesion between the micro LED and the charging by applying a voltage to a head part made of silicon. This method may cause a problem of micro LED damage due to a charging phenomenon due to the voltage applied to the head during the electrostatic induction.

X-Celeprint Inc. of the United States proposed a method of transferring a micro LED on a wafer to a desired substrate by applying a transfer head as an elastic polymer material (Publication Publication No. 2017-0019415, hereinafter referred to as `` Prevention 2 ''). box). This method has no problems with LED damage compared to the electrostatic head method, but it can transfer micro LEDs stably when the transfer force of the elastic transfer head is larger than the adhesive force of the target substrate, and requires an additional process for electrode formation. There are disadvantages. In addition, maintaining the adhesive strength of the elastomeric material is also a very important factor.

The Korean Institute of Optical Technology proposed a method for transferring micro LEDs using a cilia adhesive structure head (registered patent publication No. 1754528, hereinafter referred to as 'prior invention 3'). However, the preceding invention 3 has a disadvantage in that it is difficult to manufacture the adhesive structure of the cilia.

The Korea Institute of Machinery and Materials proposed a method of transferring micro LEDs by coating an adhesive on a roller (registered patent publication No. 1757404, hereinafter referred to as 'prior invention 4'). However, the present invention 4 requires the continuous use of the adhesive, and there is a disadvantage that the micro LED may be damaged when the roller is pressed.

Samsung Display proposed a method of transferring micro LEDs to an array substrate by electrostatic induction by applying a negative voltage to the first and second electrodes of the array substrate while the array substrate is in solution. 2017-0026959, hereinafter referred to as `` First Invention 5 ''). However, the prior invention 5 has a disadvantage in that a separate solution is required in that the micro LED is transferred to the array substrate by soaking in a solution, and then a drying process is required.

LG Electronics has proposed a method of arranging a head holder between a plurality of pickup heads and a substrate and deforming its shape by the movement of the plurality of pickup heads to provide a degree of freedom to the plurality of pickup heads. -2017-0024906, hereinafter referred to as 'prior invention 6'). However, the present invention 6 is a method of transferring a micro LED by applying a bonding material having an adhesive force to the adhesive surface of the plurality of pickup heads, there is a disadvantage that a separate process for applying a bonding material to the pickup head is required.

In order to solve the problems of the preceding inventions, the above-mentioned disadvantages should be improved while adopting the basic principles adopted by the preceding inventions. These disadvantages are derived from the basic principles adopted by the preceding inventions. There are limits to improving the shortcomings. Accordingly, the applicant of the present invention is not only to improve the disadvantages of the prior art, but to propose a new method that has not been considered in the prior inventions at all.

Registered Patent Publication No. 0731673 Published Patent Publication No. 2014-0112486 Korean Laid-Open Patent Publication No. 2017-0019415 Registered Patent Publication No. 1754528 Registered Patent Publication No. 1757404 Patent Publication No. 10-2017-0026959 Patent Publication No. 10-2017-0024906

Accordingly, an object of the present invention is to solve the problems of the micro LED transfer system proposed to date and to provide a micro LED transfer system capable of transferring the micro LED more effectively using a vacuum suction force.

In order to achieve the object of the present invention, the micro LED transfer system according to the present invention, a vacuum pump; An adsorption head for adsorbing micro LEDs by a vacuum suction force according to the operation of the vacuum pump; And a valve openable so that the vacuum pressure applied to the suction head is equal to the pressure of the transfer space.

In addition, when the suction head adsorbs the micro LED, the vacuum pump is operated while the valve is closed to adsorb the micro LED with a vacuum suction force, and when the adsorption head detaches the micro LED, the valve is removed. Open to release the vacuum suction force to desorb the micro LED adsorbed on the adsorption head.

In addition, the suction head and the vacuum pump comprises a pipe connecting, characterized in that the valve is connected to the pipe.

In addition, it comprises a target substrate provided with a bonding layer, characterized in that for opening the valve in the state in which the micro LED adsorbed on the suction head in contact with the bonding layer.

In addition, it comprises a target substrate provided with a bonding layer, characterized in that for opening the valve in a state in which the micro LED adsorbed on the suction head is spaced apart from the bonding layer.

The pipe may include a common pipe and a plurality of branch pipes connected to the common pipe, and a plurality of air flow paths connected to each of the plurality of branch pipes may be formed in the support member.

In addition, the valve is characterized in that connected to the common pipe.

In addition, the adsorption head includes an adsorption member for vacuum adsorption of the micro LED; And a support member for supporting the suction member.

In addition, it characterized in that it comprises a vacuum chamber formed between the suction member and the support member.

In addition, it characterized in that it comprises a porous member formed between the suction member and the support member.

In addition, the suction member is characterized in that it has a vertical suction hole.

As described above, the micro LED transfer system according to the present invention can more effectively transfer the micro LED.

1 is a view showing a micro LED to be the transfer target of the embodiment of the present invention.
2 is a view of a micro LED structure is transferred to the display substrate mounted in accordance with an embodiment of the present invention.
3 to 5 show a micro LED transfer system according to a first preferred embodiment of the present invention.
6 shows a micro LED transfer system according to a second preferred embodiment of the present invention.
7 is a view showing a modification of the micro LED transfer system according to the second preferred embodiment of the present invention.
8 illustrates a micro LED transfer system according to a third preferred embodiment of the present invention.
9 shows a micro LED transfer system according to a fourth preferred embodiment of the present invention.
10 is a view showing a modification of the micro LED transfer system according to the fourth embodiment of the present invention.
11 illustrates a micro LED transfer system according to a fifth preferred embodiment of the present invention.
12 is a view showing a modification of the micro LED transfer system according to the fifth preferred embodiment of the present invention.
Figure 13 illustrates a micro LED transfer system according to a sixth preferred embodiment of the present invention.
14 is a view showing a modification of the micro LED transfer system according to the sixth preferred embodiment of the present invention.

The following merely illustrates the principles of the invention. Therefore, those skilled in the art may implement the principles of the invention and invent various devices included in the concept and scope of the invention, although not explicitly described or illustrated herein. In addition, all conditional terms and embodiments listed herein are in principle clearly intended to be understood only for the purpose of understanding the concept of the invention and are not to be limited to the specifically listed embodiments and states. .

The above objects, features, and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, and thus, it will be possible to easily implement the technical idea of self-invention having ordinary skill in the art. .

Embodiments described herein will be described with reference to cross-sectional and / or perspective views, which are ideal exemplary views of the invention. The thicknesses of the films and regions and the diameters of the holes shown in these figures are exaggerated for the effective explanation of the technical contents. The shape of the exemplary diagram may be modified by manufacturing techniques and / or tolerances. In addition, the number of micro-LEDs shown in the drawings is only a part of the drawings for illustrative purposes. Accordingly, the embodiments of the present invention are not limited to the specific forms shown, but also include changes in forms generated according to manufacturing processes.

In various embodiments of the present disclosure, components that perform the same function will be given the same names and the same reference numbers for convenience, even though the embodiments are different. In addition, the configuration and operation already described in another embodiment will be omitted for convenience.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a plurality of micro LEDs 100 to be adsorbed by a micro LED adsorbent according to a preferred embodiment of the present invention. The micro LED 100 is fabricated and positioned on the growth substrate 101.

The growth substrate 101 may be made of a conductive substrate or an insulating substrate. For example, the growth substrate 101 may be formed of at least one of sapphire, SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, Ge, and Ga ₂ O ₃ .

The micro LED 100 may include a first semiconductor layer 102, a second semiconductor layer 104, an active layer 103 formed between the first semiconductor layer 102 and the second semiconductor layer 104, and a first contact electrode ( 106 and a second contact electrode 107.

The first semiconductor layer 102, the active layer 103, and the second semiconductor layer 104 may be formed of metal organic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), or plasma chemical vapor deposition (CVD). Plasma-Enhanced Chemical Vapor Deposition (PECVD), Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE), or the like.

The first semiconductor layer 102 may be implemented with, for example, a p-type semiconductor layer. The p-type semiconductor layer is a semiconductor material having a composition formula of InxAlyGa1-x-yN (0≤x≤1, 0≤y≤1, 0≤x + y≤1), for example, GaN, AlN, AlGaN, InGaN, InN , InAlGaN, AlInN, and the like, and p-type dopants such as Mg, Zn, Ca, Sr, and Ba may be doped. The second semiconductor layer 104 may be formed, for example, including an n-type semiconductor layer. The n-type semiconductor layer is a semiconductor material having a composition formula of InxAlyGa1-x-yN (0≤x≤1, 0≤y≤1, 0≤x + y≤1), for example, GaN, AlN, AlGaN, InGaN, InNInAlGaN , AlInN, and the like, and n-type dopants such as Si, Ge, Sn, and the like may be doped.

However, the present invention is not limited thereto, and the first semiconductor layer 102 may include an n-type semiconductor layer, and the second semiconductor layer 104 may include a p-type semiconductor layer.

The active layer 103 is a region where electrons and holes are recombined. The active layer 103 may transition to a low energy level as the electrons and holes recombine, and may generate light having a corresponding wavelength. The active layer 103 may include, for example, a semiconductor material having a compositional formula of InxAlyGa1-x-yN (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1), and It may be formed of a quantum well structure or a multi quantum well structure (MQW). In addition, a quantum wire structure or a quantum dot structure may be included.

The first contact electrode 106 may be formed on the first semiconductor layer 102, and the second contact electrode 107 may be formed on the second semiconductor layer 104. The first contact electrode 106 and / or the second contact electrode 107 may comprise one or more layers and may be formed of various conductive materials including metals, conductive oxides and conductive polymers.

The plurality of micro LEDs 100 formed on the growth substrate 101 are cut along the cutting line using a laser or the like, or separately separated by an etching process, and the plurality of micro LEDs 100 are separated by the laser lift-off process. It can be made to be in a state detachable from 101.

In Figure 1 'p' means the pitch interval between the micro LED 100, 's' means the separation distance between the micro LED 100, 'w' means the width of the micro LED (100).

FIG. 2 is a view illustrating a micro LED structure formed by being transferred to a display substrate by a micro LED adsorbent according to a preferred embodiment of the present invention.

The display substrate 300 may include various materials. For example, the display substrate 300 may be made of a transparent glass material mainly containing SiO ₂ . However, the display substrate 300 is not necessarily limited thereto, and may be formed of a transparent plastic material to have solubility. Plastic materials include insulating polyethersulphone (PES), polyacrylate (PAR, polyacrylate), polyetherimide (PEI), polyethylene naphthalate (PEN, polyethyelenen napthalate), polyethylene terephthalate (PET) polyethyeleneterepthalate, polyphenylene sulfide (PPS), polyallylate, polyimide, polycarbonate (PC), cellulose tri acetate (TAC), cellulose acetate propionate: CAP) may be an organic material selected from the group consisting of.

When the image is a bottom emission type implemented in the direction of the display substrate 300, the display substrate 300 should be formed of a transparent material. However, when the image is a top emission type that is implemented in a direction opposite to the display substrate 300, the display substrate 300 may not necessarily be formed of a transparent material. In this case, the display substrate 300 may be formed of metal.

When the display substrate 300 is formed of metal, the display substrate 300 may include at least one selected from the group consisting of iron, chromium, manganese, nickel, titanium, molybdenum, stainless steel (SUS), Invar alloy, Inconel alloy, and Kovar alloy. It may include, but is not limited thereto.

The display substrate 300 may include a buffer layer 311. The buffer layer 311 may provide a flat surface and may block foreign matter or moisture from penetrating. For example, the buffer layer 311 may be formed of inorganic materials such as silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, aluminum nitride, titanium oxide, or titanium nitride, or organic materials such as polyimide, polyester, and acryl. And may be formed of a plurality of laminates of the illustrated materials.

The thin film transistor TFT may include an active layer 310, a gate electrode 320, a source electrode 330a, and a drain electrode 330b.

Hereinafter, the thin film transistor TFT will be described as a top gate type in which the active layer 310, the gate electrode 320, the source electrode 330a, and the drain electrode 330b are sequentially formed. However, the present embodiment is not limited thereto, and various types of thin film transistors (TFTs), such as a bottom gate type, may be employed.

The active layer 310 may include a semiconductor material, for example, amorphous silicon or poly crystalline silicon. However, the present embodiment is not limited thereto, and the active layer 310 may contain various materials. In some embodiments, the active layer 310 may contain an organic semiconductor material.

In another alternative embodiment, the active layer 310 may contain an oxide semiconductor material. For example, the active layer 310 may be formed of Group 12, 13, 14 metal elements such as zinc (Zn), indium (In), gallium (Ga), tin (Sn) cadmium (Cd), germanium (Ge), and combinations thereof. Oxides of the selected materials.

A gate insulating layer 313 is formed on the active layer 310. The gate insulating layer 313 insulates the active layer 310 and the gate electrode 320. The gate insulating layer 313 may be formed of a multilayer or a single layer formed of an inorganic material such as silicon oxide and / or silicon nitride.

The gate electrode 320 is formed on the gate insulating layer 313. The gate electrode 320 may be connected to a gate line (not shown) for applying an on / off signal to the thin film transistor TFT.

The gate electrode 320 may be made of a low resistance metal material. The gate electrode 320 is made of aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg) in consideration of adhesion to adjacent layers, surface flatness of the stacked layers, and workability. , Gold (Au), Nickel (Ni), Neodymium (Nd), Iridium (Ir), Chromium (Cr), Lithium (Li), Calcium (Ca), Molybdenum (Mo), Titanium (Ti), Tungsten (W) It may be formed of a single layer or multiple layers of one or more materials of copper (Cu).

An interlayer insulating layer 315 is formed on the gate electrode 320. The interlayer insulating layer 315 insulates the source electrode 330a, the drain electrode 330b, and the gate electrode 320. The interlayer insulating film 315 may be formed of a multilayer or a single layer of an inorganic material. For example, the inorganic material may be a metal oxide or a metal nitride. Specifically, the inorganic material may be silicon oxide (SiO ₂ ), silicon nitride (SiNx), silicon oxynitride (SiON), aluminum oxide (Al ₂ O ₃ ), or titanium oxide ( TiO ₂ ), tantalum oxide (Ta ₂ O ₅ ), hafnium oxide (HfO ₂ ), zinc oxide (ZrO ₂ ), and the like.

The source electrode 330a and the drain electrode 330b are formed on the interlayer insulating film 315. The source electrode 330a and the drain electrode 330b include aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), and neodymium (Nd). ), Iridium (Ir), chromium (Cr), lithium (Li), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), copper (Cu) of one or more materials Can be formed. The source electrode 330a and the drain electrode 330b are electrically connected to the source region and the drain region of the active layer 310, respectively.

The planarization layer 317 is formed on the thin film transistor TFT. The planarization layer 317 is formed to cover the thin film transistor TFT, thereby eliminating a step resulting from the thin film transistor TFT and making the top surface flat. The planarization layer 317 may be formed of a single layer or multiple layers of an organic material. Organic materials include general purpose polymers such as polymethylmethacrylate (PMMA) and polystylene (PS), polymer derivatives having phenolic groups, acrylic polymers, imide polymers, arylether polymers, amide polymers, fluorine polymers, and p-xylene Polymers, vinyl alcohol-based polymers and blends thereof, and the like. In addition, the planarization layer 317 may be formed of a composite laminate of an inorganic insulating film and an organic insulating film.

The first electrode 510 is positioned on the planarization layer 317. The first electrode 510 may be electrically connected to the thin film transistor TFT. In detail, the first electrode 510 may be electrically connected to the drain electrode 330b through a contact hole formed in the planarization layer 317. The first electrode 510 may have various shapes. For example, the first electrode 510 may be patterned in an island shape. The bank layer 400 defining the pixel region may be disposed on the planarization layer 317. The bank layer 400 may include a recess in which the micro LED 100 is to be accommodated. For example, the bank layer 400 may include a first bank layer 410 forming a recess. The height of the first bank layer 410 may be determined by the height and the viewing angle of the micro LED 100. The size (width) of the recess may be determined by the resolution, the pixel density, and the like of the display device. In one embodiment, the height of the micro LED 100 may be greater than the height of the first bank layer 410. The concave portion may have a rectangular cross-sectional shape, but embodiments of the present invention are not limited thereto, and the concave portion may have various cross-sectional shapes such as polygons, rectangles, circles, cones, ellipses, and triangles.

The bank layer 400 may further include a second bank layer 420 on the first bank layer 410. The first bank layer 410 and the second bank layer 420 may have a step difference, and the width of the second bank layer 420 may be smaller than the width of the first bank layer 410. The conductive layer 550 may be disposed on the second bank layer 420. The conductive layer 550 may be disposed in a direction parallel to the data line or the scan line and electrically connected to the second electrode 530. However, the present invention is not limited thereto, and the second bank layer 420 may be omitted, and the conductive layer 550 may be disposed on the first bank layer 410. Alternatively, the second bank layer 420 and the conductive layer 500 may be omitted, and the second electrode 530 may be formed on the entire substrate 301 as a common electrode common to the pixels P. The first bank layer 410 and the second bank layer 420 may include a material that absorbs at least a portion of light, a light reflecting material, or a light scattering material. The first bank layer 410 and the second bank layer 420 may include an insulating material that is translucent or opaque to visible light (eg, light in the wavelength range of 380 nm to 750 nm).

For example, the first bank layer 410 and the second bank layer 420 may include polycarbonate (PC), polyethylene terephthalate (PET), polyethersulfone, polyvinylbutyral, polyphenylene ether, polyamide, poly Thermoplastic resins such as etherimide, norbornene system resins, methacryl resins, cyclic polyolefins, epoxy resins, phenol resins, urethane resins, acrylic resins, vinyl ester resins, imide resins, urethane resins, and urea It may be formed of a thermosetting resin such as resin, melamine resin, or an organic insulating material such as polystyrene, polyacrylonitrile, polycarbonate, but is not limited thereto.

As another example, the first bank layer 410 and the second bank layer 420 may be formed of an inorganic insulating material such as inorganic oxides such as SiOx, SiNx, SiNxOy, AlOx, TiOx, TaOx, ZnOx, and inorganic nitride. It is not limited to this. In one embodiment, the first bank layer 410 and the second bank layer 420 may be formed of an opaque material, such as a black matrix material. Insulating black matrix materials include organic resins, resins or pastes comprising glass paste and black pigments, metal particles such as nickel, aluminum, molybdenum and alloys thereof, metal oxide particles (eg chromium oxide), Or metal nitride particles (eg, chromium nitride) or the like. In a modification, the first bank layer 410 and the second bank layer 420 may be distributed Bragg reflectors (DBRs) having high reflectivity or mirror reflectors formed of metal.

The micro LED 100 is disposed in the recess. The micro LED 100 may be electrically connected to the first electrode 510 in the recess.

The micro LED 100 emits light having a wavelength of red, green, blue, white, and the like, and white light may be realized by using a fluorescent material or combining colors. The micro LED 100 has a size in units of micrometers (μm). Each of the micro LEDs 100 is picked up on the growth substrate 101 by an adsorbent according to an exemplary embodiment of the present invention, and transferred to the display substrate 300 by recesses of the display substrate 300. Can be accommodated in

The micro LED 100 includes a p-n diode, a first contact electrode 106 disposed on one side of the p-n diode, and a second contact electrode 107 positioned opposite to the first contact electrode 106. The first contact electrode 106 may be connected to the first electrode 510, and the second contact electrode 107 may be connected to the second electrode 530.

The first electrode 510 may include a reflective film formed of Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a compound thereof, and a transparent or translucent electrode layer formed on the reflective film. The transparent or translucent electrode layer may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide (In ₂ O _3, indium oxide), and indium gallium. At least one selected from the group consisting of oxide (IGO; indium gallium oxide) and aluminum zinc oxide (AZO) may be provided.

The passivation layer 520 surrounds the micro LED 100 in the recess. The passivation layer 520 fills the space between the bank layer 400 and the micro LED 100 to cover the recess and the first electrode 510. The passivation layer 520 may be formed of an organic insulating material. For example, the passivation layer 520 may be formed of acrylic, poly (methyl methacrylate) (PMMA), benzocyclobutene (BCB), polyimide, acrylate, epoxy, polyester, and the like, but is not limited thereto. It is not.

The passivation layer 520 is formed above the micro LED 100, for example, at a height not covering the second contact electrode 107, so that the second contact electrode 107 is exposed. A second electrode 530 electrically connected to the exposed second contact electrode 107 of the micro LED 100 may be formed on the passivation layer 520.

The second electrode 530 may be disposed on the micro LED 100 and the passivation layer 520. The second electrode 530 may be formed of a transparent conductive material such as ITO, IZO, ZnO, or In ₂ O ₃ .

Micro LED transfer system according to a preferred embodiment of the present invention

3 to 5 show a micro LED transfer system according to a first embodiment of the present invention. 3 to 5, the micro LED transfer system according to the first exemplary embodiment of the present invention includes an adsorption head 1000, a vacuum pump 2000, and a valve 3000.

When the adsorption head 1000 adsorbs the micro LED ML, the vacuum pump 2000 is operated while the valve 3000 is closed to adsorb the micro LED ML by the vacuum suction force. When the micro LED ML is detached, the valve 3000 is opened to remove the vacuum suction force to desorb the micro LED ML adsorbed on the adsorption head 1000.

The suction head 1000 is configured as a picker that absorbs the micro LEDs ML by a vacuum suction force according to the operation of the vacuum pump 2000 and transfers the micro LEDs ML from the first substrate to the second substrate.

The adsorption head 1000 includes an adsorption member 1100 for vacuum adsorption of the micro LED ML and a support member 1200 for supporting the adsorption member 1100 and having an air passage 1210 formed therein.

The adsorption member 1100 is provided with pores therein to vacuum suck the micro LED (ML) from the bottom by using the vacuum suction force generated by the operation of the vacuum pump 2000.

Adsorption member 1100 may be composed of a porous member (P) having pores.

Porous member (P) is composed of a material containing a large number of pores therein, it may be composed of a powder, a thin film / thick film and a bulk having a porosity of about 0.2 ~ 0.95 in a predetermined arrangement or disordered pore structure. . The pores of the porous member P can be classified into micro pores of 2 nm or less in diameter, meso pores of 2 to 50 nm, and macro pores of 50 nm or more, depending on their size. At least in part. The porous member P may be classified into organic, inorganic (ceramic), metal, and hybrid porous materials according to its constituents. Although a porous member having arbitrary pores is shown in FIG. 3, the porous member P according to the first embodiment also includes a porous member (for example, an anodized film described later) in which pores are vertically formed in a predetermined arrangement.

The porous member (P) can be powder, coating film, bulk in terms of shape, and in the case of powder, various shapes such as spherical, hollow spherical, fiber, tubular, etc. are possible, and the powder may be used as it is, but as a starting material It is also possible to manufacture and use a coating film and a bulk shape.

The porous member P having the optional pores shown in FIG. 3 forms a flow path connecting the upper and lower portions of the porous member P while the plurality of arbitrary pores are connected to each other inside the porous member P. The porous member P having such optional pores can be made porous by sintering an aggregate composed of inorganic material granules and a binder bonding the aggregates together. In this case, the porous member P has a plurality of pores irregularly connected to each other to form a gas flow path, and the surface and the back surface of the porous member P are communicated with each other by the gas flow path.

The micro LED ML is disposed on the substrate S, and the substrate S is supported by the substrate support 5000. 3, the substrate S may be a growth substrate 101, a temporary substrate, or a carrier substrate when the adsorption head 1000 adsorbs the micro LEDs ML. When the suction head 1000 is in a state after transferring the micro LED ML, the substrate S may be the display substrate 300 or the target substrate.

The support member 1200 supports the adsorption member 1100 inserted into the recess formed in the lower portion from above.

An air passage 1210 is formed in the support member 1200 to be in fluid communication with the pores of the adsorption member 1100, and the air passage 1210 receives the vacuum suction force generated by the vacuum pump 2000. It performs a function of delivering to the adsorption member (1100).

The pipeline 4000 connects the suction head 1000 and the vacuum pump 2000. That is, the upper portion of the suction member 1100 is provided with a conduit 4000 through which air flows by a vacuum suction force operated by the vacuum pump 2000 to communicate with the air flow passage 1210.

The valve 3000 is connected to the pipeline 4000. If the valve 3000 is provided on one side of the conduit 4000 to have a structure that allows the inside of the conduit 4000 to communicate with the transfer space or has a structure that allows the inside of the conduit 4000 to be sealed with the transfer space, there is no limitation thereto.

The valve 3000 is installed in an openable structure, and the vacuum pressure applied to the suction head 1000 when the valve 3000 is opened is equal to the pressure of the transfer space of the micro LED ML. When opening the valve 3000, the suction head 1000 detaches the micro LED ML as the vacuum pressure inside the suction head 1000 generated by the vacuum pump 2000 is equal to the pressure of the transfer space. To be transferred to the target substrate TS.

A process of transferring the micro LED ML from the first substrate (donor substrate, DS) to the second substrate (target substrate, TS) will be described with reference to FIG. 4. FIG. 4A illustrates a state in which the adsorption head 1000 is positioned on the first substrate DS and before the micro LEDs ML are adsorbed. At this time, the valve 3000 is in a closed state. In this state, the vacuum pump 2000 is operated to generate a vacuum suction force, so that the adsorption head 1000 adsorbs the micro LED ML. The adsorption head 1000 may support and adsorb the micro LEDs ML with suction force while being spaced apart from the micro LEDs ML, or the adsorption head 1000 descends and contacts the upper surface of the micro LEDs ML. It can adsorb micro LED (ML) with suction power in the state.

After the adsorption head 1000 completes adsorption of the micro LED ML, the adsorption head 1000 is raised and moved to the second substrate TS as shown in FIG. 4B. At this time, the valve 3000 remains closed.

FIG. 4C is a diagram illustrating a state in which the suction head 1000 transfers the micro LED ML to the second substrate TS. Looking at the process, the adsorption head 1000 is lowered onto the second substrate (TS) to transfer the micro LED (ML) to the second substrate (TS). Then, the operation of the vacuum pump 2000 is stopped and the valve 3000 is opened. As the valve 3000 is opened, the vacuum pressure acting on the upper portion of the micro LED ML becomes equal to the vacuum pressure of the transfer space, and thus the vacuum suction force of the micro LED 100 adsorbed to the adsorption member 1100. By removing this, the micro LED ML is detached and transferred to the second substrate TS.

A process of transferring the micro LED ML to the second substrate TS will be described in more detail with reference to FIG. 5. Referring to FIG. 5, a bonding layer 5500 for bonding the micro LED ML to the target substrate TS is provided on the second substrate TS. In the process of bonding the micro LED ML to the bonding layer 5500, the micro LED ML is bonded by applying heat and pressure to the bonding layer 5500.

The bonding layer 5500 may be formed of an electrically conductive adhesive material including conductive particles. For example, the bonding layer 5500 may be composed of a movable conductive film or an anisotropic conductive adhesive. Meanwhile, the bonding layer 5500 may be formed of a material such as a thermoplastic or thermosetting polymer, and may be formed using a micro LED (ML) using an eutectic alloy bonding, a transition liquid bonding, or a solid phase diffusion bonding method. ) May be selected from the materials for joining.

When the second substrate TS is the display substrate 300 illustrated in FIG. 2, the second substrate TS may include a first electrode electrically connected to the first contact electrode 106 of the micro LED ML. 510 is formed. A bonding layer 5500 is provided on the first electrode 510 to electrically connect the first contact electrode 106 and the first electrode 510 of the micro LED ML, as well as to connect the micro LED ML. It serves to fix to the target substrate.

The adsorption head 1000 may transfer the micro LED ML to the second substrate TS in two ways. The first case is a case where the bottom surface of the adsorption member 1100 is detached from the top surface of the micro LED ML and the micro LED ML adsorbed on the adsorption head 1000 is transferred to the second substrate TS. The second case is a case where the lower surface of the adsorption member 1100 is in contact with the upper surface of the micro LED ML, and the micro LED ML adsorbed on the adsorption head 1000 is detached and transferred to the second substrate TS. .

In the first case above, the adsorption head 1000 operates the vacuum pump 2000 in reverse (or switches with each other with two vacuum pumps) to desorb the micro LEDs ML. If the air is blown out through the suction surface of the micro LED (ML) falls, there is a fear that position error occurs. In addition, when the air is ejected through the adsorption surface of the adsorption member 1100, foreign matters or particles stuck to the adsorption surface drop off and adhere to the bonding layer 5500 on the second substrate TS. And the bonding efficiency between the bonding layer 5500 may decrease.

As such, when the vacuum pump 2000 is operated in reverse (or two vacuum pumps are switched to each other) to eject air through the adsorption surface of the adsorption member 1100, the micro LED ML may be more easily detached. Although, the transfer position precision and transfer efficiency of the micro LED ML are deteriorated.

Therefore, when the suction head 1000 transfers the micro LED ML to the second substrate TS, the valve 3000 is opened while the operation of the vacuum pump 2000 is stopped. By making the working vacuum pressure the same as the vacuum pressure of the transfer space, it is preferable that the micro LED ML is transferred to the second substrate TS.

In the second case, there is a fear that the position error of the micro LED (ML) occurs by the air ejected through the adsorption surface of the adsorption member (1100).

On the other hand, in the case where the bonding layer 5000 is heated and bonded to a specific temperature of 200 ° C. or more, the micro LED ML is brought into contact with the bonding layer 5000 while being bonded to the bonding layer 5000 in a state of being heated. . In this case, the bonding force between the micro LED ML and the bonding layer 5000 is greater than that between the adsorption head 1000 and the micro LED ML so that the micro LED ML is transferred to the second substrate TS. Therefore, the suction head 1000 cannot be lifted from the second substrate TS until sufficient bonding force is generated between the micro LED ML and the bonding layer 5000. As such, the micro LED (ML) should be bonded to the bonding layer 5000 while the bonding layer 5000 is heated to a specific temperature. The air blown out through the adsorption surface of the adsorption member 1100 is lower than the bonding temperature ( Since the air is ejected at room temperature), the time taken to raise the adsorption layer 5000 to a specific temperature is delayed by the low temperature air that is ejected, and as a result, the transfer speed per unit time of the adsorption head 1000 is lowered.

As described above, when the air is ejected through the adsorption surface of the adsorption member 1100 by operating the vacuum pump 2000, the desorption of the micro LED ML may be more easily performed, but the micro LED is caused by the air ejected through the adsorption surface. There is a problem that the transfer position accuracy and the joining efficiency of the ML are lowered.

Therefore, when the suction head 1000 transfers the micro LED ML to the second substrate TS, the valve 3000 is opened while the operation of the vacuum pump 2000 is stopped. By making the working vacuum pressure the same as the vacuum pressure of the transfer space, it is preferable to transfer the micro LED ML to the second substrate TS.

6 is a view showing a micro LED transfer system according to a second embodiment of the present invention. The micro LED transfer system according to the second embodiment has a difference in configuration of the conduit 4000 of the micro LED transfer system according to the first embodiment.

Referring to FIG. 6, the conduit 4000 includes a common conduit 4100 and a plurality of branch conduits 4300 which are divided from the common conduit 4100 and connected to the common conduit 4100. In addition, a plurality of air passages 1210 connected to each of the branch pipe lines 4300 are formed in the support member 1200.

The branch pipe line 4300 is the first-first branch pipe line 4311 connected to any one of the air flow passages 1210 of the support member 1200, and the other of the air flow passages 1210 of the support member 1200. It consists of a first separation pipe (4310) consisting of a first-second branch pipe (4313) connected to. The first branch conduit 4310, which is composed of the first-first branch conduit 4311 and the first-second branch conduit 4313, disperses the vacuum suction input generated from the vacuum pump 2000 to absorb the adsorbing member 1100. To pass on. Through this, it is possible to minimize the non-uniformity of the vacuum suction input that may occur in the adsorption member 1100.

In the pipeline 4000 including the common pipeline 4100 and the branch pipeline 4300 branched from the common pipeline 4100, the valve 3000 is connected to the common pipeline 4100. When the valve 3000 installed on the common pipe line 4100 is opened through such a configuration, the same vacuum pressure as that of the transfer space is transmitted to the branch pipe line 4300, thereby improving uniformity of desorption of the micro LEDs ML. .

FIG. 7 is a modified example of the micro LED transfer system according to the second preferred embodiment of the present invention, and the branch conduit 4300 of FIG. 6 is further branched. Referring to FIG. 7, the branch pipe line 4300 includes a first branch pipe line 4310 and a second branch pipe line 4320 branched from the first branch pipe line 4310. In other words, the first branch pipe line 4310 is composed of the 1-1,1-2 branch pipe lines 4311 and 4313 branched from the common pipe 4100, and the second branch pipe line 4320 is made of the first branch pipe line 4320. 2-1 branched in branch pipe line 4311, 2-1 branched in branch pipe line 2213, 2-2 branched pipe line 4320, and branched in branch 1-2 branch pipe line 4313 It consists of a three branch pipe line 4325 and the 2-4 branch pipe line (4327). Each end of the 2-1 to 2-4 branch pipe lines 4321, 4323, 4325, and 4327 is connected to the air flow passage 1210 of the support member 1200.

As such, according to the configuration in which the branch line 4300 is further branched, the vacuum suction input generated by the operation of the vacuum pump 2000 connected to the common line 4100 is more uniformly distributed to the suction member 1100 side. The same vacuum pressure as that of the transfer space generated by the opening of the valve 3000 connected to the common pipe 4100 can be more uniformly distributed to the adsorption member 1100 side, so that the transfer efficiency of the micro LED ML can be improved. This is improved.

8 is a view showing a micro LED transfer system according to a third embodiment of the present invention. The micro LED transfer system according to the third embodiment has a difference in configuration of the supporting member 1200 of the micro LED transfer system according to the first embodiment.

The adsorption head 1000 of the micro LED transfer system according to the third embodiment supports an adsorption member 1100 for vacuum adsorption of the micro LEDs ML, an adsorption member 1100, and an air flow path 1210 formed therein. It comprises a member 1200, a vacuum pressure chamber 1300 formed on the support member 1200 and a pipe line 4000 in communication with the vacuum pressure chamber 1300.

Referring to FIG. 8, a suction member 1100 is fixedly installed under the support member 1200, and a plurality of air flow passages 1210 are formed on the suction member 1100. The vacuum chamber 1300 is provided above the plurality of air passages 1210. The vacuum chamber 1300 is connected to the vacuum pump 2000 through a conduit 4000. The valve 3000 may be connected to the conduit 4000 or may be connected to the vacuum chamber 1300.

The plurality of air flow passages 1210 are provided between the vacuum chamber 1300 and the suction member 1100 to distribute the vacuum suction input applied to the vacuum chamber 1300 to the suction member 1100. 8 illustrates that the plurality of air flow passages 1210 are equally disposed with the same width, but the plurality of air flow passages 1210 may consider the uniformity of the vacuum suction force of the adsorption member 1100 in consideration of the uniformity of the central portion than the peripheral portion. The width of the air passage 1210 disposed at a narrower interval or positioned at the peripheral portion may be larger than the width of the air passage 1210 positioned at the central portion.

The closer to the conduit 4000, the greater the vacuum suction force, and the farther it is from the conduit 4000, the smaller the vacuum suction force. However, the micro LED transfer system according to the third embodiment has a configuration in which a vacuum pressure chamber 1300 is formed under the conduit 4000, and a plurality of air flow paths 1210 are formed under the vacuum pressure chamber 1300. Through this, it is possible to achieve uniformity of the adsorption force on the adsorption surface of the adsorption member 1100. In addition, when the valve 3000 connected to the conduit 4000 or the vacuum chamber 1300 is opened, the vacuum pressure of the transfer space delivered to the suction member 1100 is dispersed through the plurality of air flow passages 1210 and uniformized. Therefore, the desorption uniformity of the micro LED (ML) is improved.

9 illustrates a micro LED transfer system according to a fourth preferred embodiment of the present invention. The micro LED transfer system according to the fourth embodiment has a difference in configuration of the adsorption member 1100 of the micro LED transfer system according to the first embodiment.

The adsorption head 1000 of the micro LED transfer system according to the fourth embodiment includes an adsorption member 1100 (P1) for vacuum adsorption of the micro LEDs ML and a support member for supporting the adsorption member 1100 (P1). And 1200. The valve 3000 is connected to the conduit 4000.

An adsorption hole 1110 is formed in the adsorption member 1100 (P1). The adsorption hole 1110 is formed to vertically penetrate the adsorption member 1100 (P1) using a laser or etching.

If the width of the adsorption hole 1110 can be formed in a unit of several tens of micrometers (μm) or less, the adsorption member 1100 (P1) may be formed of metal, nonmetal, ceramic, glass, quartz, silicon (PDMS), resin, or the like. It may be made of a material. When the material of the adsorption member 1100 (P1) is a metal material, it may have an advantage of preventing static electricity during transfer of the micro LED (ML). When the material of the adsorption member 1100 (P1) is a non-metallic material, the material does not have metal properties, and the effect of the adsorption member 1100 (P1) on the micro LEDs (ML) can be minimized. That has the advantage. When the adsorption member 1100 (P1) is made of a material such as ceramic, glass, or quartz, it is advantageous to secure rigidity, and the thermal deformation coefficient is low, so that the heat deformation of the adsorption member 1100 (P1) during the transfer of the micro LED (ML). It is possible to minimize the risk of the occurrence of position error due to. If the adsorption member 1100 (P1) is made of silicon or PDMS material, even if the lower surface of the adsorption member 1100 (P1) is in direct contact with the upper surface of the micro LED (ML), the shock absorbing function is performed to collide with the micro LED (ML). This can minimize the risk of damage. When the material of the adsorption member 1100 (P1) is made of a resin material, it may have an advantage that the fabrication of the adsorption member 1100 (P1) is simple.

The vacuum chamber 1300 is provided on the upper portion of the suction member 1100 (P1). The vacuum chamber 1300 communicates with the air passage 1210 formed in the support member 1200 to transfer the vacuum suction force generated from the vacuum pump 2000 to the adsorption member 1100 (P1) or to open the valve 3000. As a function of transferring the vacuum pressure of the transfer space to the adsorption member (1100 (P1)).

10 is a modification of the micro LED transfer system according to the fourth preferred embodiment of the present invention.

While the vacuum chamber 1300 shown in FIG. 9 is formed as an empty space, the modification of the fourth embodiment is the vacuum chamber 1300 shown in FIG. 9, as shown in FIG. 10. There is a difference in that the porous member P having arbitrary pores is provided.

The porous member P may be composed of the porous member described in the first embodiment. The porous member P not only diffuses the vacuum suction force generated at the upper portion thereof in a horizontal direction through arbitrary pores provided therein, but also serves to transfer the vacuum suction force to the adsorption member 1100 (P1). It serves to support the adsorption member 1100 (P1) provided. As a result, even if the thickness of the adsorption member 1100 (P1) is reduced, the bending of the adsorption member 1100 (P1) is prevented, thereby adsorbing the member 1100 (P1) having the vertical adsorption hole 1110. It is easy to manufacture, the vertically formed suction hole 1110 is formed to correspond to the pitch interval of the micro LED (ML) it is possible to transfer the micro LED (ML).

11 is a view showing a micro LED transfer system according to a fifth embodiment of the present invention. The micro LED transfer system according to the fifth embodiment has a difference in configuration of the adsorption member 1100 of the micro LED transfer system according to the first embodiment.

The adsorption member 1100 (P2) may be an anodized film having pores 1110 formed by anodizing a metal. The anodization film refers to a film formed by anodizing a metal as a base material, and the pores 1110 refer to a hole formed in a process of forming an anodization film by anodizing a metal. For example, when the base metal is aluminum (Al) or an aluminum alloy, when the base material is anodized, an anodized film made of anodized aluminum (Al ₂ O ₃ ) is formed on the surface of the base material. As described above, the formed anodization film is divided into a barrier layer in which pores 1110 are not formed therein and a porous layer in which pores 1110 are formed therein. The barrier layer is located on top of the base material, and the porous layer is located on top of the barrier layer. As such, when the base material is removed from the base material on which the anodization film having the barrier layer and the porous layer is formed on the surface, only the anodization film made of anodized aluminum (Al ₂ O ₃ ) material remains. The anodization film has pores having a regular arrangement while having a uniform diameter and a vertical shape.

The interior of the anodization film can form an air flow path in a vertical shape by vertical pores 1110. The inner width of the pores 1110 has a size of several nm to several hundred nm. For example, when the size of the micro LED (ML) to be vacuum adsorbed is 30 μm × 30 μm and the inside width of the pores 1110 is several nm, the micro LEDs (ML) using approximately tens of millions of pores 1110 are used. ) Can be vacuum adsorbed. On the other hand, when the size of the micro LED (ML) to be vacuum suction is 30μm x 30μm and the inside width of the pores 1110 is hundreds of nm, the micro LED (ML) using approximately tens of thousands of pores (1110). Can be adsorbed in vacuum. In the case of the micro LED (ML), basically, the first semiconductor layer 102, the second semiconductor layer 104, the active layer 103 formed between the first semiconductor layer 102 and the second semiconductor layer 104, Since only the first contact electrode 106 and the second contact electrode 107 are relatively light, vacuum adsorption is possible using tens of thousands to tens of millions of pores 1110 of the anodization film.

The vacuum chamber 1300 is provided on the anodization film. The vacuum chamber 1300 is connected to a vacuum pump for supplying a vacuum. The vacuum chamber 1300 functions to apply a vacuum or release the vacuum to a plurality of vertical pores of the anodization film according to the operation of the vacuum pump.

Upon adsorption of the micro LED ML, the vacuum applied to the vacuum chamber 1300 is transferred to a plurality of pores 1110 of the anodization film to provide a vacuum adsorption force for the micro LED ML. On the other hand, when the micro LED ML is detached, the valve 3000 is opened, so that the vacuum pressure is also equal to the air pressure of the transfer space in the plurality of pores 1110 of the anodic oxide film, so that the vacuum to the micro LED ML is reduced. Adsorption force is removed.

11 shows the pores 1110 having a shape of penetrating both upper and lower sides, but the anodizing film adsorbs the adsorption region for vacuum adsorption of the micro LEDs (ML) and the micro LEDs (ML). It may be configured to include a non-adsorption area that does not. The adsorption region is a region in which the vacuum of the vacuum chamber 1300 is transferred to vacuum the micro LEDs ML, and the non-adsorption region is a micro LED (ML) as the vacuum of the vacuum chamber 1300 is not transmitted. This area is not adsorbed.

Preferably, the adsorption region may be a region through which the upper and lower portions of the pores 1110 pass, and the non-adsorption region may be a region in which at least one portion of the upper and lower portions of the pores 1110 is closed.

The non-adsorption region may be implemented by forming a shield on at least part of the surface of the anodization film. The shield is formed to block the inlet of the pores 1110 exposed to at least part of the surface of the anodization film. The shield may be formed on at least some of the upper and lower surfaces of the anodization film. The shielding portion is not limited in material, shape, and thickness as long as the shielding portion can perform a function of blocking an inlet of the pores 1110 exposed to the surface of the anodization film. Preferably, the turn may be further formed of a photoresist (including PR, dry film PR) or a metal material, and may be a barrier layer.

The non-adsorption region may be formed by closing one of the upper and lower portions of the vertical pores 1110 by the barrier layer formed during the production of the anodization layer, and the adsorption region may be removed by etching or the like. Thus, the upper and lower portions of the vertical pores 1110 may be formed to penetrate each other.

In addition, since the pores 1110 penetrating up and down are formed as a part of the barrier layer is removed, the thickness of the anodic oxide film in the adsorption region is smaller than the thickness of the anodic oxide film in the non-adsorption region.

A support portion for reinforcing the strength of the anodization film is further formed on the non-adsorption area. In one example, the support may be a base metal material. The base metal material may be supported on the barrier layer without removing the base metal material used during anodization. A metal base material is provided in the non-adsorption area to secure the rigidity of the anodic oxide film. By the configuration of the support unit as described above, it is possible to increase the strength of the anodic oxide film having a relatively weak strength, it is possible to increase the size of the adsorption head (1000) consisting of anodized film.

In addition, as the adsorption member 1100 (P2) is composed of an anodized film, the thermal flatness coefficient of the anodized film is 2 to 3 ppm / ° C., so that the adsorption head 1000 adsorbs and transfers the micro LED (ML), Since it is possible to minimize the thermal deformation, it is possible to exert an effect that the fear of position error is significantly lowered.

12 is a diagram showing a modification of the micro LED transfer system according to the fifth embodiment of the present invention.

A modification of the fifth embodiment is different in that the porous member P is provided in the vacuum chamber 1300 shown in FIG. 11, as shown in FIG. 12.

The porous member P may be made of the porous member P described in the first embodiment. The porous member P not only diffuses the vacuum suction force generated at the upper portion thereof in a horizontal direction through arbitrary pores provided therein, but also serves to transfer the suction suction force 1100 (P1) to the lower portion thereof. It serves to support the adsorption member 1100 (P2) provided. Through this, even if the thickness of the adsorption member 1100 (P2) is reduced, the occurrence of warpage of the adsorption member 1100 (P2) is prevented.

13 is a view showing a micro LED transfer system according to a sixth preferred embodiment of the present invention.

While the adsorption member 1100 (P2) according to the fifth embodiment is to vacuum the micro LED (ML) by using pores 1110 naturally generated when anodizing a metal to produce an anodized film, The adsorption member 1100 (P2) according to the sixth embodiment has a difference in that the adsorption hole 1110 is additionally formed separately from the pores of the anodization film.

Adsorption holes 1110 are formed to penetrate the upper and lower surfaces of the anodization film. The diameter of the adsorption hole 1110 is larger than the diameter of naturally occurring pores of the anodization film. The adsorption hole 1110 having a diameter larger than the diameter of the naturally occurring pores is formed, so that the vacuum adsorption on the micro LED (ML) compared to the configuration of vacuum adsorption of the micro LED (ML) only by the pores of the anodized film. You can increase the area. The adsorption hole 1110 may be formed by etching the anodization film in a vertical direction after the aforementioned anodization film and pores are formed. Through this, only the pores of the anodization film formed in the size of several nm to several hundred nm can compensate for the fact that the vacuum pressure is slightly lowered when the micro LED (ML) is vacuum adsorbed.

In addition, since the vacuum pressure of the transfer space due to the opening of the valve 3000 can be more quickly transmitted to the adsorption member 1100 (P1), the desorption efficiency of the micro LED ML is improved.

14 is a view showing a modification of the micro LED transfer system according to the sixth preferred embodiment of the present invention.

The modification of the sixth embodiment is different in that the porous member P is provided in the vacuum chamber 1300 shown in FIG. 13, as shown in FIG. 14.

The porous member P may be made of the porous member P described in the first embodiment. The porous member P not only diffuses the vacuum suction force generated at the upper portion thereof in a horizontal direction through arbitrary pores provided therein, but also serves to transfer the vacuum suction force to the adsorption member 1100 (P2). It serves to support the adsorption member 1100 (P2) provided. Through this, even if the thickness of the adsorption member 1100 (P2) is reduced, the occurrence of warpage of the adsorption member 1100 (P2) is prevented.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art various modifications of the present invention without departing from the spirit and scope of the invention described in the claims below. Or it may be modified.

1000: adsorption head 2000: vacuum pump
3000: valve 4000: pipeline

Claims (11)

A vacuum pump;
An adsorption head for adsorbing micro LEDs by a vacuum suction force according to the operation of the vacuum pump; And
And an openable valve so that the vacuum pressure applied to the suction head is equal to the pressure of the transfer space.
The method of claim 1,
When the adsorption head adsorbs the micro LED, the vacuum pump is operated while the valve is closed to adsorb the micro LED with vacuum suction force, and when the adsorption head desorbs the micro LED, the valve is opened. And releasing the vacuum suction force to desorb the micro LED absorbed by the suction head.
The method of claim 1,
Including a conduit for connecting the suction head and the vacuum pump,
And the valve is connected to the conduit.
The method of claim 1,
A target substrate having a bonding layer,
And opening the valve in a state in which the micro LED adsorbed to the adsorption head contacts the bonding layer.
The method of claim 1,
A target substrate having a bonding layer,
The micro LED transfer system, characterized in that for opening the valve in a state in which the micro LED adsorbed to the adsorption head is spaced apart from the bonding layer.
The method of claim 3, wherein
The conduit includes a common conduit and a plurality of branch conduits connected to the common conduit,
And a plurality of air flow paths connected to each of the plurality of branch pipes in the support member.
The method of claim 6,
The valve is micro LED transfer system, characterized in that connected to the common pipe.
The method of claim 1,
The adsorption head
An adsorption member for vacuum adsorbing the micro LED; And
Micro LED transfer system comprising a; support member for supporting the adsorption member.
The method of claim 8,
And a vacuum pressure chamber formed between the suction member and the support member.
The method of claim 8,
Micro LED transfer system comprising a porous member formed between the suction member and the support member.
The method of claim 8,
And said adsorption member has a vertical adsorption hole.

Images