Ultra-small LED chip rework apparatus using transfer method and rework method thereof

Abstract

A micro LED chip rework device using a transfer method according to the present invention is a micro LED chip rework device for removing a defective micro LED chip that is misaligned or has a performance defect among a plurality of micro LED chips transferred by a first adhesive layer on a substrate, and is characterized by comprising: a detach pressure head that is in the shape of a stick and has a second adhesive layer with a stronger adhesive force than the first adhesive layer provided at the bottom of the stick shape, and is pressed against the upper surface of the defective micro LED chip to transfer and remove the defective micro LED chip attached to the first adhesive layer to the second adhesive layer; and a driving unit that moves the detach pressure head in the X, Y, and Z axis directions on the substrate.

Description

Technology Field

[0001] The present invention relates to a micro LED chip rework device and rework method, and more specifically, to a micro LED chip rework device and rework method using a transfer method that can rapidly and accurately remove a defective micro LED chip from a substrate using a transfer method when a mis-alignment defect occurs due to minor vibration or shock during the chip bonding process, and furthermore, rapidly and accurately attach a micro LED chip for rework to the substrate using a transfer method in the place where the defective micro LED chip was removed, thereby reducing the takt time and significantly improving process efficiency and precision. Background Technology

[0002] Recently, ultra-small LEDs (light emitting diodes) ranging in size from tens to hundreds of μm are increasingly being used as light sources for various displays due to their various advantages, such as miniaturization, lightweight design, and low power consumption.

[0003] These ultra-small LEDs can be classified according to chip size into mini LEDs with a chip size of 100 μm to 300 μm and micro LEDs with a chip size of 5 μm to 100 μm.

[0004] In the case of the above-mentioned mini LED, the chip size is relatively larger than that of the above-mentioned micro LED, so it is utilized in backlight units that display images on LCD displays primarily through backlighting, rather than in direct-emitting pixels of LED displays.

[0005] On the other hand, Micro LEDs are expected to be in the spotlight as next-generation ultra-small LED chip devices because they can be applied to optical applications requiring miniaturization (integration), low power consumption, and lightweight design. However, since their chip size is even smaller than that of the aforementioned Mini LEDs, allowing each individual LED chip to be used as a separate pixel or light source, research is actively underway to utilize these Micro LEDs as pixels for LED displays that display images through direct light emission by arranging them horizontally or vertically.

[0006] Figure 1 is a plan view showing the configuration of a typical ultra-small LED (mini LED) array.

[0007] Referring to Figure 1 above, typically when applying such mini LEDs to a backlight unit, one or more serially connected mini LED chip groups are arranged horizontally and vertically to form a mini LED array.

[0008] In a conventional mini LED, a mini LED array (100) is provided in which a group of mini LED chips (120), in which a plurality of mini LED chips (121, 122, 123, 124) having a chip size of 100 μm to 200 μm are serially connected on a substrate (110), is arranged horizontally and vertically.

[0009] In the case of the above-mentioned mini LED, the process generally proceeds by forming the circuit of each chip on a wafer and then separating it into multiple individual chips.

[0010] The separated mini LED chips undergo several transfer processes during the packaging and module manufacturing processes to be transferred or mounted on a substrate.

[0011] Conventional LED chip transfer processes are generally carried out by transferring to a transfer tape or substrate, or by directly mounting on a circuit board (e.g., a rigid PCB or a flexible PCB). A typical type of conventional LED chip transfer process is a pick and place type transfer device.

[0012] As an example of such a pick and place type transfer device, Korean Registered Patent Publication No. 1879029 (registered July 10, 2018) discloses a chip transfer device and a transfer method in which each light-emitting diode chip is transferred to a substrate by picking up each LED chip one by one and placing it on the substrate.

[0013] Meanwhile, Korean Registered Patent Publication No. 2130124 (registered June 29, 2020) describes a mounting device for mounting a component attached to a sheet onto a substrate, comprising a head driving unit and a mounting head attached to the head driving unit. The mounting head comprises a head body, a plunger disposed on the head body and reciprocating up and down, an ejector pin fixed to the head body and penetrating the plunger in the reciprocating direction of the plunger, and a solenoid fixed to the head body and moving the plunger. The plunger is a movable iron core and has a shaft, a flange installed on the tip side of the shaft, a tip shaped tapering from the shaft, and a nipple portion having a diameter further reduced than the diameter of the thinnest portion among the tip shaped tapering from the shaft disposed at the top of the tip. The shaft and the flange are disposed inside the head body, and further A mounting device for an individual transfer method using an ejector pin is disclosed, wherein the tip portion and the nipple portion protrude from the head body, the plunger is in a state of maximum protrusion from the head body when the solenoid is off, and when the solenoid is on, the plunger moves in the direction of the head drive portion so that the ejector pin protrudes relatively from the plunger.

[0014] In addition, Korean Registered Patent Publication No. 1937017 (registered on January 3, 2019) describes a device for transporting semiconductor devices, comprising: a first frame for holding a wafer tape having a first side and a second side—wherein a plurality of semiconductor device dies are disposed on the first side of the wafer tape—; a second frame including a first clamping member and a second clamping member—wherein the second frame clamps an output substrate having a circuit trace between the first clamping member and the second clamping member, and the second frame is configured to hold the output substrate such that the circuit trace is disposed on the wafer tape toward the plurality of semiconductor device dies—; and a needle disposed adjacent to the second side of the wafer tape—wherein the length of the needle extends in a direction toward the wafer tape—; A needle actuator connected to the needle—the needle actuator moves the needle to a die transfer position where the needle presses a second side of the wafer tape so as to press one of the plurality of semiconductor device dies to contact a circuit trace on the output substrate—and a laser directed toward a portion of the output substrate corresponding to the transfer position where the semiconductor device die contacts the circuit trace to apply energy to the circuit trace to attach the semiconductor device die to the circuit trace, wherein the laser is positioned within the device such that energy from the laser is applied directly to the output substrate during the transfer operation. An individual transfer mounting device using an ejector pin (needle) is disclosed as another example.

[0015] In addition, Korean Published Patent Application No. 2020-0109493 (published September 23, 2020) describes a transfer device for transferring a semiconductor chip, comprising: a stage on which a first substrate having the semiconductor chip mounted thereon is placed on one surface; a work table on which a second substrate to which the semiconductor chip is to be transferred is placed; and a push pin module for transferring the semiconductor chip to the second substrate by pushing a portion corresponding to the semiconductor chip on the other surface of the first substrate while the first surface of the first substrate and the second substrate are arranged to face each other. A mounting device for an individual transfer method using an ejector pin (needle) is disclosed as another example, wherein the push pin module includes a push pin unit comprising a push pin for pushing the other side of the first substrate, and a load control unit for controlling the load applied to the push pin when the semiconductor chip is transferred to the second substrate, wherein the load control unit includes a VCM (voice coil motor) stator and a VCM actuator, and when the semiconductor chip is transferred to the second substrate, if a load greater than a preset load is applied to the push pin, the VCM actuator moves in the opposite direction to the direction of travel of the push pin.

[0016] However, as described above, while conventional technologies such as pick and place or individual transfer methods using ejector pins for transferring or mounting individual LED chips one by one may be applicable to LED chip processes of several hundred µm or more, in the case of micro LED chip arrays where chip size and spacing between chips are becoming increasingly finer to 5 µm to 100 µm, there was a problem in that it was difficult to respond to the pick and place method or individual transfer method due to the miniaturization of chip size and spacing between chips.

[0017] Meanwhile, considering the trend of Micro LED display screen sizes becoming larger day by day, countless fine Micro LED chips must be transferred rapidly and accurately one by one onto large-area displays; however, conventional individual transfer methods using pick and place or ejector pins faced practical limitations in accurately transferring or mounting them onto a substrate without misalignment.

[0018] In addition, even if micro LED chips are individually transferred or mounted on a substrate using conventional pick and place or ejector pin transfer methods, there was a high possibility that mis-alignment defects would occur in some ultra-small LED chips, as shown in FIG. 2, due to minor vibrations or shocks that occurred during the transfer process.

[0019] However, conventionally, there was no way to address this on-site, so many problems arose, such as increased tact time and reduced process efficiency and yield, as the aforementioned substrates had to be removed as defective substrates and retrieved before shipment or undergo a separate rework process to correct defects. Prior art literature

[0020] Korean Registered Patent No. 1937071 (Registered Jan. 03, 2019) Korean Registered Patent No. 2130124 (Registered June 29, 2020) Korean Published Patent No. 2020-0109493 (Published Sep. 23, 2020) Korean Registered Patent No. 1879029 (Registered July 10, 2018) The problem to be solved

[0021] Accordingly, the present invention is designed to resolve the aforementioned problems and aims to provide a micro LED chip rework device using a transfer method that can rapidly and accurately remove defective micro LED chips from a substrate using a transfer method when mis-alignment defects occur due to minor vibrations or shocks during the chip bonding process, and furthermore, rapidly and accurately attach a micro LED chip for rework to the substrate using a transfer method in the place where the defective micro LED chip was removed, thereby reducing the takt time and significantly improving process efficiency and precision. means of solving the problem

[0022] A micro LED chip rework device using the transfer method of the present invention for achieving the above-mentioned purpose comprises, according to one embodiment, a micro LED chip rework device for removing a defective micro LED chip that is misaligned or has a performance defect among a plurality of micro LED chips transferred by a first adhesive layer on a substrate, wherein the defective micro LED chip attached to the first adhesive layer is transferred to the second adhesive layer and removed by being pressed on the upper surface of the defective micro LED chip in a state in which a second adhesive layer with a stronger adhesive force than the first adhesive layer is provided at the bottom of the stick shape; and a driving unit for moving the detachment pressure head in the X, Y, and Z axis directions on the substrate.

[0023] In addition, according to one embodiment, the device further comprises an attachment pressure head that is moved in the X, Y, and Z axis directions on the substrate by the driving unit, and is in the shape of a stick, wherein a third adhesive layer with a weaker adhesive force than the first adhesive layer is provided at the bottom of the stick shape, and a replacement normal ultra-small LED chip for rework is attached to the bottom surface of the third adhesive layer, and is prepared in such a state that the replacement normal ultra-small LED chip attached to the third adhesive layer is transferred to the first adhesive layer and restored by applying pressure to the first adhesive layer of the defective ultra-small LED chip removed by the detach pressure head.

[0024] In addition, according to one embodiment, the driving unit comprises: a linear transfer unit that moves the detachment pressure head in the X and Y axis directions; and an up-down driving unit that raises and lowers the detachment pressure head in the Z axis direction.

[0025] In addition, according to one embodiment, the second adhesive layer is formed on one side of a first transfer film that is transported reel-to-reel in a horizontal direction, and the detach pressure head selectively presses the other side of the first transfer film in a vertical direction.

[0026] In addition, according to one embodiment, the third adhesive layer is formed on one side of the second transfer film that is transported reel-to-reel in the horizontal direction, and the attach pressure head selectively presses the other side of the second transfer film in the vertical direction.

[0027] Meanwhile, a method for reworking a micro LED chip using a transfer method according to the present invention comprises: (a) a step in which a detach pressure head is moved to a fixed position above a defective micro LED chip to be reworked, which is transferred to a first adhesive layer on a substrate, and a second adhesive layer having a stronger adhesive force than the first adhesive layer is provided at the bottom of the stick shape; (b) a step in which the detach pressure head descends and presses the first adhesive layer while the second adhesive layer is in contact with the defective micro LED chip; and (c) a step in which, as the detach pressure head rises, the defective micro LED chip transferred to the second adhesive layer having a stronger adhesive force than the first adhesive layer separates from the first adhesive layer and rises together with the detach pressure head while attached to the second adhesive layer.

[0028] Additionally, according to one embodiment, after step c, the method further comprises: (d) a step in which an attachment pressure head is positioned above the first adhesive layer from which the defective ultra-small LED chip has been removed, wherein the third adhesive layer, which is in the shape of a stick and has a lower point of the stick shape, has a weaker adhesive force than the first adhesive layer, and a replacement normal ultra-small LED chip is attached to the bottom surface of the third adhesive layer; (e) a step in which the attachment pressure head descends and presses the first adhesive layer from which the defective ultra-small LED chip has been removed, thereby transferring and restoring the replacement normal ultra-small LED chip attached to the third adhesive layer to the first adhesive layer; and (f) a step in which the attachment pressure head from which the replacement normal ultra-small LED chip has been separated rises again and returns to its original position. Effects of the invention

[0029] As described above, the present invention utilizes the difference in adhesive strength between the bottom surface of a transfer film and the top surface of a substrate to rapidly and accurately transfer a micro LED chip to a substrate, thereby reducing the takt time of the ultra-small micro LED transfer process and significantly improving process efficiency.

[0030] In addition, even if misalignment defects occur due to minor vibrations or shocks during the transfer process, the misaligned micro LED chips are immediately repaired on-site, resulting in a significant improvement in yield and productivity compared to conventional transfer methods using pick and place or ejector pins. Brief explanation of the drawing

[0031] FIG. 1 is a plan view showing the configuration of a micro LED chip array for a general backlight unit. FIG. 2 is a plan view showing an enlarged view of a micro LED chip array transferred onto a conventional substrate. FIG. 3a to 3f are operation state diagrams of a micro LED chip rework device using the transfer method of the present invention, where FIG. 3a shows a state in which a detach pressure head is positioned above a defective micro LED chip that is the target of the rework operation; FIG. 3b shows a state in which the detach pressure head descends to press the defective micro LED chip; FIG. 3c shows a state in which the detach pressure head rises after removing the defective micro LED chip by transfer; FIG. 3d shows a state in which an attach pressure head is positioned above the removed defective micro LED chip; FIG. 3e shows a state in which the attach pressure head descends to attach a normal micro LED chip for rework onto the substrate by transfer; FIG. 3f shows a state in which, after attaching the normal micro LED chip onto the substrate, the attach pressure head again Elevated state Specific details for implementing the invention

[0032] The terms used herein are used merely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising,” “having,” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described herein, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0033] Unless otherwise defined in this specification, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains.

[0034] Terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this specification.

[0035] Hereinafter, a detailed description of a micro LED chip rework device using a transfer method according to an embodiment of the present invention is as follows, with reference to the attached drawings.

[0036] FIGS. 3a to 3f are operation state diagrams of a micro LED chip rework device using the transfer method of the present invention, FIG. 3a shows a state in which a detach pressure head is positioned above a defective micro LED chip that is the target of the rework operation; FIG. 3b shows a state in which the detach pressure head is lowered to press the defective micro LED chip; FIG. 3c shows a state in which the detach pressure head is raised after removing the defective micro LED chip by transfer; FIG. 3d shows a state in which an attach pressure head is positioned above the removed defective micro LED chip; FIG. 3e shows a state in which the attach pressure head is lowered to attach a normal micro LED chip for rework onto a substrate by transfer; FIG. 3f shows a state in which the attach pressure head is raised again after attaching the normal micro LED chip onto the substrate.

[0037] The micro LED chip rework device (300) using the transfer method of the present invention is a device for removing and replacing defective micro LED chips (FC) that are misaligned or have performance defects among a plurality of micro LED chips (NC) transferred by the first adhesive layer (AL1) on a substrate (S).

[0038] The micro LED chip (NC) transferred onto the substrate (S) may be a flexible micro LED array in which a plurality of micro LED chips (NC) having a size of 20㎛ × 40㎛ are repeatedly arranged at regular intervals (e.g., 20㎛) on a flexible substrate (S) by a transfer method. (See FIG. 2)

[0039] In order to selectively rework a defective micro LED chip (FC) among the above-mentioned multiple micro LED chips (NC), the rework device (300) of the present invention is provided with a stick-shaped detachment pressure head (310) that removes the defective micro LED chip (FC) attached to the first adhesive layer (AL1) by transferring it to the second adhesive layer (AL2) and removing it by applying pressure to the upper surface of the defective micro LED chip (FC) in a state in which a second adhesive layer (AL2) with a stronger adhesive force than the first adhesive layer (AL1) is provided at the bottom of the stick.

[0040] Referring to FIGS. 3a to 3f, the second adhesive layer (AL2) may be formed on one side of a first transfer film (TF1) that is reel-to-reel transferred in a horizontal direction according to one embodiment, that is, the second adhesive layer (AL2) may be implemented in the form of an adhesive tape for transfer applied to one side of the first transfer film (TF1).

[0041] In this state, the detach pressure head (310) selectively presses the other side of the first transfer film (TF1) in the vertical direction to transfer the defective micro LED chip (FC) to the second adhesive layer (AL2) and remove it from the first adhesive layer (AL1), and thereafter, the first transfer film (TF1) that has been removed can be reel-to-reel transferred one step at a certain distance in the horizontal direction for the next detach transfer operation.

[0042] In addition, a driving unit (320) is provided to move the detach pressure head (310) in the X, Y, and Z axis directions on the substrate (S).

[0043] According to one embodiment, the driving unit (320) may be composed of a linear transfer unit (not shown) that moves the detachment pressure head (310) in a plane in the X and Y axis directions, and an up-down driving unit (not shown) that raises and lowers the detachment pressure head (310) in the Z axis direction.

[0044] In addition, an attachment pressure head (330) is provided on one side of the detach pressure head (310).

[0045] The above-mentioned attachment pressure head (330) is moved in the X, Y, and Z axis directions on the substrate (S) by the driving unit (320) and is formed into a stick shape of micro-size overall, and a third adhesive layer (AL3) with weaker adhesive strength than the first adhesive layer (AL1) is provided at the bottom of the stick shape.

[0046] At this time, a replacement normal micro LED chip (RC) for rework is prepared with the bottom surface of the third adhesive layer (AL3) attached, and the replacement normal micro LED chip (RC) attached to the third adhesive layer (AL3) is transferred to the first adhesive layer (AL1) by applying pressure to the first adhesive layer (AL1) of the defective micro LED chip (FC) removed by the detach pressure head (310) to restore it.

[0047] Referring to FIGS. 3a to 3f, the third adhesive layer (AL3) may be formed on one side of a second transfer film (TF2) that is reel-to-reel transferred in a horizontal direction, according to one embodiment, so that the third adhesive layer (AL3) may be implemented in the form of an adhesive tape for transfer applied to one side of the second transfer film (TF2).

[0048] In this state, the attachment pressure head (330) selectively presses the other side of the second transfer film (TF2) in the vertical direction to transfer the replacement normal micro LED chip (RC) to the first adhesive layer (AL1) and restore it, and thereafter, the second transfer film (TF2) that has completed the restoration can be transferred reel-to-reel by a certain distance in the horizontal direction for the next attachment transfer operation.

[0049] In this case, according to one embodiment, the substrate (S) may be a flexible plastic substrate.

[0050] In addition, according to one embodiment, the first adhesive layer (AL1) formed between the substrate (S) and the micro LED chip, the second adhesive layer (AL2) provided on the detach pressure head (310), and the third adhesive layer (AL3) provided on the attach pressure head (330) may be adhesives that can be attached and detached multiple times, that is, adhesives that can be repeatedly attached and detached.

[0051] In addition, according to one embodiment, the first adhesive layer (AL1), the second adhesive layer (AL2), and the third adhesive layer (AL3) may be adhesives in which an ester rubber containing atrylate or silicone, a phenolic resin, etc., is used as an auxiliary agent, and a low molecular weight material such as polyisobutylene is added thereto, but are not limited thereto.

[0052] Meanwhile, according to another embodiment, the first adhesive layer (AL1) may be a hot-melt adhesive that selectively imparts adhesive strength or bonding strength by applying heat or energy.

[0053] In addition, according to one embodiment, the first adhesive layer (AL1), the second adhesive layer (AL2), and the third adhesive layer (AL3) may each be applied to the upper surface of the substrate (S) or to the lower point of the detach pressure head (310) or the attach pressure head (330) by means of a dispenser device using a liquid adhesive.

[0054] Meanwhile, according to another embodiment, the first adhesive layer (AL1) may be an electrically conductive adhesive.

[0055] More specifically, the first adhesive layer (AL1) may be an electrically conductive adhesive containing one or more types of metallic fillers such as silver, gold, copper, nickel, palladium, platinum, iron, tungsten, molybdenum, zinc, or aluminum that do not contain lead (Pb), or conductive carbon materials such as carbon nanotubes, graphene, graphite, or carbon black.

[0056] In the case of the above metallic filler, since its melting point is higher than that of lead, there is a concern that functional components may be subject to thermal damage during the mounting process, so it may be a conductive adhesive capable of low-temperature bonding at about 150°C as a lead-free bonding.

[0057] More specifically, the conductive adhesive may be one in which the content of the expensive conductive filler is reduced and mechanical properties are increased by using a material that has corresponding conductivity and excellent thermal or physical properties, such as a conductive nanomaterial having a one-dimensional structure, namely metal nanowires or carbon nanotubes, even though the aforementioned expensive conductive filler is included in a low content.

[0059] Hereinafter, with reference to FIGS. 3a to 3f, the method for reworking a micro LED chip using the transfer method of the present invention is described step-by-step as follows.

[0060] Step (a) (see FIG. 3a): A detach pressure head (310) is moved and positioned above a defective micro LED chip (FC) that is to be reworked and transferred to a first adhesive layer (AL1) on a substrate (S), and is equipped with a second adhesive layer (AL2) that has a stronger adhesive force than the first adhesive layer (AL1) at the bottom of the stick shape.

[0061] At this time, the screening inspection of the above defective micro LED chip (FC) can be performed by a separate vision unit (not shown).

[0062] Step (b) (see FIG. 3b): Next, the detach pressure head (310) is lowered onto the defective micro LED chip (FC), and accordingly, the second adhesive layer (AL2) provided at the bottom of the detach pressure head (310) is pressed while in contact with the upper surface of the defective micro LED chip (FC).

[0063] Step (c) (see FIG. 3c): As the detach pressure head (310) rises again, the defective micro LED chip (FC) transferred to the second adhesive layer (AL2), which has a stronger adhesive force than the first adhesive layer (AL1), is separated from the first adhesive layer (AL1) and rises together with the detach pressure head (310) while attached to the second adhesive layer (AL2).

[0064] That is, as the defective micro LED chip (FC) rises while attached to the second adhesive layer (AL2), it is separated and removed from the first adhesive layer (AL1), and at this time, only the first adhesive layer (AL1) remains on the upper surface of the substrate (S).

[0065] Step (d) (see FIG. 3d): Subsequently, an attachment pressure head (330) is positioned above the first adhesive layer (AL1) from which the defective micro LED chip (FC) was removed in step (c).

[0066] As previously described, the above-mentioned attachment pressure head (330) is in the shape of a stick, and a third adhesive layer (AL3) with a weaker adhesive force than the first adhesive layer (AL1) is provided at the bottom of the stick shape, and a replacement normal micro LED chip (RC) is attached to the bottom surface of the third adhesive layer (AL3).

[0067] That is, in order to replace the removed defective micro LED chip (FC) with a replacement normal micro LED chip (RC), the attachment pressure head (330) is positioned above the first adhesive layer (AL1) from which the defective micro LED chip (FC) was removed.

[0068] Step (e) (see FIG. 3e): Subsequently, as the attachment pressure head (330) descends and presses the first adhesive layer (AL1) from which the defective micro LED chip (FC) has been removed, the replacement normal micro LED chip (RC) attached to the third adhesive layer (AL3) at the bottom of the attachment pressure head (330) is transferred to the first adhesive layer (AL1) from which the defective micro LED chip (FC) has been removed.

[0069] Step (f) (see FIG. 3f): Finally, as the attachment pressure head (330) rises, the attachment pressure head (330) moves upward and returns to its original position, leaving only the replacement normal micro LED chip (RC) attached to the first adhesive layer (AL1) from which the defective micro LED chip (FC) has been removed.

[0070] In summary, after the detach pressure head (310) is positioned above a specific misaligned defective micro LED chip (FC), it descends and pressurizes the second adhesive layer (AL2) of the detach pressure head (310) as it comes into contact with the upper surface of the defective micro LED chip (FC).

[0071] In this state, since the adhesive force of the second adhesive layer (AL2) is greater than the adhesive force of the first adhesive layer (AL1), the misaligned defective micro LED chip (FC) is transferred (attached) to the second adhesive layer (AL2) of the detach pressure head (310) and is removed (separated) from the substrate (S) as it rises together with the detach pressure head (310).

[0072] Next, after the attachment pressure head (330) is positioned in the place where the misaligned defective micro LED chip (FC) was removed (upper surface of the first adhesive layer), the attachment pressure head descends and transfers the replacement normal micro LED chip (RC), which is attached to the third adhesive layer (AL3) and is in a ready state, to the place where the misaligned defective micro LED chip (FC) was removed (upper surface of the first adhesive layer), thereby completing the replacement of the LED chip.

[0074] Furthermore, the present invention is not limited solely to the embodiment described above. Since the same effect can be achieved even when the detailed configuration, number, or arrangement structure of the device is changed, it is hereby specified that those skilled in the art can add, delete, or modify various configurations within the scope of the technical concept of the present invention. Explanation of the symbols

[0075] 300: Rework device (of the present invention) 310: Detach pressure head 320 : Driving unit 330 : Attach pressure head TF1: 1st transfer film TF2: 2nd transfer film AL1: First adhesive layer AL2: Second adhesive layer AL3: 3rd adhesive layer S: Substrate NC: Normal micro LED chip FC: Defective micro LED chip RC: Replacement normal ultra-small LED chip

Claims

Claim 1 A micro LED chip rework device for removing defective micro LED chips that are misaligned or have performance defects among a plurality of micro LED chips transferred by a first adhesive layer on a substrate, comprising: a detach pressure head having a stick shape and a second adhesive layer having a stronger adhesive force than the first adhesive layer provided at the bottom of the stick shape, which is pressed against the upper surface of the defective micro LED chip to transfer and remove the defective micro LED chip attached to the first adhesive layer to the second adhesive layer; and a driving unit for moving the detach pressure head in the X, Y, and Z axis directions on the substrate. and is provided on one side of the detach pressure head and moves in the X, Y, and Z axis directions on the substrate by the driving unit, and is configured in a stick shape, wherein a third adhesive layer with a weaker adhesive force than the first adhesive layer is provided at the bottom of the stick shape, and a replacement normal ultra-small LED chip is attached to the bottom surface of the third adhesive layer, and is prepared in such a state that the normal ultra-small LED chip attached to the third adhesive layer is transferred to the first adhesive layer and restored by applying pressure to the first adhesive layer of the defective ultra-small LED chip removed by the detach pressure head; wherein the second adhesive layer is configured to be formed on one surface of a first transfer film that is transported reel-to-reel in the horizontal direction, and the detach pressure head selectively presses the other surface of the first transfer film in the vertical direction, and the third adhesive layer is transported reel-to-reel in the horizontal direction A micro LED chip rework device using a transfer method, characterized in that it is configured to be formed on one side of a second transfer film, and the attachment pressure head selectively presses the other side of the second transfer film in a vertical direction. Claim 2 delete Claim 3 A micro LED chip rework device using a transfer method, wherein the driving unit comprises: a linear transfer unit that moves the detach pressure head in the X and Y axis directions; and an up-down driving unit that raises and lowers the detach pressure head in the Z axis direction. Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 delete

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