Micro LED transfer device

Abstract

A micro LED transfer device according to an embodiment of the present invention may comprise: a stage unit on which a target substrate is seated; a die to which a carrier substrate having a micro LED chip bonded thereto is fixed, and which is made of a transparent material; an alignment imaging unit for aligning the target substrate and the carrier substrate by imaging alignment marks provided on the stage unit and the die; a laser head for irradiating laser light on the carrier substrate; and a control unit for controlling the operation of the stage unit, the alignment imaging unit and the laser head.

Description

Micro LED transfer device

[0001] The present invention relates to a micro LED transfer device, and more particularly, to a micro LED transfer device for transferring a micro LED chip attached to a carrier substrate to a target substrate.

[0002] Recently developed display devices include liquid crystal displays (LCDs), organic light-emitting diode (OLED) displays, and quantum dot light-emitting diode (QLED) displays.

[0003] Among these, liquid crystal display devices lack a self-luminous means on the display panel. Consequently, liquid crystal display devices require a separate backlight to supply light to the display panel, and nitride-based light-emitting diodes (LEDs) are primarily used as light sources.

[0004] Meanwhile, micro LEDs generally refer to LEDs measuring 100㎛ or less on a side. This is approximately one-tenth or less the size of a standard LED. Micro LEDs are known to be approximately 20% more energy efficient than standard LEDs, and their small size also results in less heat generation and power consumption. Due to these advantages, extensive research is being conducted to apply micro LEDs to display devices.

[0005] For display devices constructed using micro LEDs, the development of a technology to quickly and accurately transfer a large quantity of such small-sized micro LEDs onto a panel substrate or a target substrate for sorting is required.

[0006] When transferring micro LEDs in this way, a camera would previously move forward and backward between the head and the stage, capturing images of the carrier substrate placed on the head side and the target substrate placed on the stage side to align them. However, there was a problem where, after the camera was aligned and moved backward, the head would lower to transfer the micro LEDs, causing deformation due to the surrounding environment (temperature), resulting in misalignment.

[0007] In addition, the forward and backward cameras for alignment are mounted on a cantilever-shaped structure and moved on the transfer device. However, since the ambient temperature must be maintained at approximately 150° by a heater installed on the stage side, there was a problem that the temperature difference from room temperature was large, causing thermal deformation of the structure.

[0008] One embodiment of the present invention provides a micro LED transfer device that performs alignment in advance in a pre-alignment imaging unit and performs additional alignment in an alignment imaging unit before micro LED transfer, thereby preventing alignment from being misaligned during the lowering process of a head unit and improving transfer quality.

[0009] In addition, one embodiment of the present invention provides a micro LED transfer device that can move at a constant height without sagging due to load or thermal deformation because the free alignment imaging unit moves while being supported on both sides by guide rails arranged in parallel.

[0010] The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned herein will be clearly understood by those skilled in the art from the description below.

[0011] A micro LED transfer device according to one embodiment of the present invention may include a stage portion on which a target substrate is mounted; a die on which a carrier substrate having a micro LED chip attached thereto is fixed and made of a transparent material; an alignment imaging portion that captures alignment marks provided on the stage portion and the die to align the target substrate and the carrier substrate; a laser head that irradiates laser light onto the carrier substrate; and a control portion that controls the operations of the stage portion, the alignment imaging portion, and the laser head.

[0012] The above die can be made of quartz material.

[0013] The above alignment marks may be arranged in pairs diagonally centered on the target substrate and the carrier substrate.

[0014] The above alignment mark may include a first alignment mark provided on the stage portion; and a second alignment mark provided on the die.

[0015] The above die and the laser head are installed in a head section, and the head section can be raised or lowered relative to the stage section.

[0016] The above alignment imaging unit can perform alignment by imaging while the head unit is lowered for transfer of the micro LED chip.

[0017] In the above stage section, the target substrates are arranged in a plurality of columns and rows, and the alignment marks can be provided around the periphery of the target substrates arranged on the outside.

[0018] The above alignment marks may be provided in two numbers around the target substrate.

[0019] The device may further include a pre-alignment imaging unit that is movably installed between the stage unit and the die and captures and aligns the target substrate and the carrier substrate.

[0020] The above-mentioned pre-aligned imaging unit may further include a pair of guide rails that are installed movably while being supported on both sides.

[0021] According to one embodiment of the present invention, alignment is performed in advance in the pre-alignment imaging unit, and the alignment imaging unit performs additional alignment before micro LED transfer, thereby preventing misalignment during the lowering process of the head unit and improving transfer quality.

[0022] In addition, according to one embodiment of the present invention, since the free-alignment imaging unit moves while being supported on both sides by guide rails arranged in parallel, it is possible to move at a constant height without sagging due to load or thermal deformation.

[0023] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0024] FIG. 1 is a perspective view illustrating a micro LED transfer device according to one embodiment of the present invention.

[0025] FIG. 2 is a perspective view illustrating the bottom surface of a die of a micro LED transfer device according to one embodiment of the present invention.

[0026] Figure 3 is a drawing illustrating alignment of a target substrate and a carrier substrate before transfer of a micro LED.

[0027] FIG. 4 is a drawing illustrating another example of aligning a target substrate and a carrier substrate before transferring a micro LED.

[0028] FIG. 5a and FIG. 5b are drawings showing another example of a first substrate stage on which a target substrate is placed.

[0029] Figure 6 is a drawing showing a pre-aligned imaging unit coupled to a guide rail unit.

[0030] Figure 7 is a drawing schematically showing the arrangement position of the guide rail part.

[0031] Figure 8 is a drawing showing the side structure of the pre-alignment imaging unit.

[0032] Figure 9 is a perspective view showing the internal cross-section of the pre-alignment imaging unit.

[0033] Fig. 10 is a cross-sectional view showing an example of a combined structure of a pre-aligned imaging unit and an imaging unit mounting unit.

[0034] Figure 11 is a cross-sectional view showing the second housing in Figure 10 rotated downward.

[0035] Fig. 12 is a cross-sectional view showing another example of the combined structure of a pre-aligned imaging unit and an imaging unit mounting unit.

[0036] FIG. 13 is a side view illustrating a pre-alignment imaging unit moving forward for alignment according to one embodiment of the present invention.

[0037] FIG. 14 is a side view illustrating a pre-alignment imaging unit moved backward after alignment according to one embodiment of the present invention.

[0038] FIG. 15 is a side view illustrating an alignment imaging unit lowered for alignment according to one embodiment of the present invention.

[0039] The present invention is susceptible to various modifications and embodiments, and specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the present invention to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention. In describing the present invention, detailed descriptions of related known technologies will be omitted if they are deemed to obscure the gist of the present invention.

[0040] Terms such as first, second, etc. may be used to describe various components, but these components should not be limited by these terms. These terms are used solely to distinguish one component from another.

[0041] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0042] Additionally, throughout the specification, when we say "connected," this does not only mean that two or more components are directly connected, but also that two or more components are indirectly connected through other components, that they are electrically connected as well as physically connected, or that they are referred to by different names depending on location or function but are one.

[0043] Additionally, when described as being formed or arranged "above or below" each component, "above" or "below" includes not only cases where the two components are in direct contact with each other, but also cases where one or more other components are formed or arranged between the two components. Furthermore, when expressed as "above" or "below," it can include the meaning of a downward direction as well as an upward direction based on one component.

[0044] Hereinafter, one embodiment of a micro LED transfer device according to the present invention will be described in detail with reference to the attached drawings. In the description with reference to the attached drawings, identical or corresponding components are assigned the same drawing numbers, and redundant descriptions thereof will be omitted.

[0045] FIG. 1 is a perspective view illustrating a micro LED transfer device according to one embodiment of the present invention, FIG. 2 is a perspective view illustrating a bottom surface of a die of a micro LED transfer device according to one embodiment of the present invention, FIG. 3 is a view illustrating alignment of a target substrate and a carrier substrate before transfer of a micro LED, and FIG. 4 is a view illustrating another example of alignment of a target substrate and a carrier substrate before transfer of a micro LED.

[0046] As shown here, a micro LED transfer device according to one embodiment of the present invention may include a stage unit (100), a head unit (200), a die (300), an alignment imaging unit (330), a pre-alignment imaging unit (400), a guide rail unit (500), and a control unit (600).

[0047] A stage unit (100), a head unit (200), and a control unit (600) may be installed on the base (1). In the present embodiment, the base (1) may include a lower base (10), a side base (20) disposed on the side of the lower base (10) and extending vertically, and an upper base (30) disposed flatly on the top of the side base (20). However, this is merely an example, and the base (1) may be formed in various structures to support the micro LED transfer device. The control unit (600) may control the operation of the stage unit (100), the alignment imaging unit (330), and the laser head (220).

[0048] A stage portion (100) is installed on the upper surface of the lower base (10). The stage portion (100) may include a base stage (110), a first moving stage (120), a second moving stage (130), a first substrate stage (140), and a second substrate stage (150).

[0049] The base stage (110) is fixedly installed on the upper surface of the lower base (10). In addition, the first moving stage (120) is installed on the upper side of the base stage (110) so as to be movable in the X-axis direction, and the second moving stage (130) is installed on the upper side of the first moving stage (120) so as to be movable in the Y-axis direction. A first substrate stage (140) on which a target substrate (160) is mounted is fixedly installed on the upper side of the second moving stage (130). The target substrate (160) is mounted on the first substrate stage (140), and a carrier substrate (320) is mounted on the second substrate stage (150).

[0050] The position of the target substrate (160) can be set by the movement of the first moving stage (120) and the second moving stage (130) in the X-axis and Y-axis directions. The coupling structure of the stage unit (100) described above is merely an example, and any coupling structure can be applied as long as it is configured to perform movement of the target substrate (160) in the X-axis and Y-axis directions. For example, the target substrate (160) can be moved by being placed on a stage that can move in the X-axis and Y-axis directions.

[0051] The target substrate (160) may be a panel to which micro LED chips of a carrier substrate (320) are transferred and bonded, or may be another carrier substrate (320) used for the purpose of transferring only good micro LED chips, defective micro LED chips, or pre-designated micro LED chips among the micro LED chips of the carrier substrate (320) for sorting, etc.

[0052] The second substrate stage (150) can be placed on one side of the first substrate stage (140), and is positioned below the head unit (200) by the movement of the first moving stage (120) and the second moving stage (130) in the X-axis and Y-axis directions while the carrier substrate (320) is secured thereon. At this time, the head unit (200) is lowered, and the carrier substrate (320) is fixed to the surface by suction from the die (300), and then raised. When the carrier substrate (320) is raised, the first moving stage (120) and the second moving stage (130) are moved in the X-axis and Y-axis directions so that the target substrate (160) is positioned below the carrier substrate (320).

[0053] A head unit (200) is installed above the stage unit (100) to be raised and lowered. The head unit (200) moves the carrier substrate (320) toward the target substrate (160) while moving relative to the stage unit (100) in the Z-axis direction. The head unit (200) can be raised and lowered from the inside of the head plate (210) installed on the upper surface of the upper base (30).

[0054] A laser head (220) is installed on the upper side of the head unit (200). The laser head (220) irradiates laser light to a carrier substrate (320) fixed to the die (300) for transferring a micro LED chip. The laser head (220) is fixed to the head unit (200) and is raised and lowered together with the head unit (200) to irradiate laser light to the carrier substrate (320).

[0055] Referring to Fig. 2, a die (300) is installed at the lower portion of the head portion (200). A carrier substrate (320) is provided on the lower surface of the die (300), and the carrier substrate (320) can be fixed to the die (300) by suction. The die (300) can be made in the shape of a plate having a predetermined thickness.

[0056] In the present embodiment, the primary alignment of the target substrate (160) and the carrier substrate (320) can be performed by the pre-alignment imaging unit (400) described later. At this time, there may be a problem that the alignment with the target substrate (160) is misaligned during the process of lowering the carrier substrate (320) by lowering the head unit (200) after alignment by the pre-alignment imaging unit (400). Therefore, in the present embodiment, a second alignment mark (310) for alignment is provided on the die (300) side so that the carrier substrate (320) can be additionally aligned with the target substrate (160) in a lowered state before transfer.

[0057] In addition, in order to capture the first alignment mark (170) formed on the target substrate (160) and the second alignment mark (310) of the carrier substrate (320) while the head unit (200) is lowered before transfer, the die (300) may be made of a transparent material. For example, the die (300) may be made of a transparent quartz material. In addition, an alignment imaging unit (330) for capturing the first alignment mark (170) and the second alignment mark (310) is installed in the head unit (200). In order for the alignment imaging unit (330) to simultaneously capture the first alignment mark (170) and the second alignment mark (310), it is difficult to confirm the alignment state of both from one side if the die (300) is not made of a transparent material. Therefore, in this embodiment, the die (300) is made of a transparent material and the alignment imaging unit (330) is placed on the head unit (200) side, thereby enabling alignment between the target substrate (160) and the carrier substrate (320).

[0058] In this way, by performing alignment in advance in the pre-alignment imaging unit (400) and performing additional alignment in the alignment imaging unit (330) before micro LED transfer, the alignment can be prevented from being misaligned during the lowering process of the head unit (200) and the transfer quality can be improved. Since it is difficult for the pre-alignment imaging unit (400) to move between the head unit (200) and the stage unit (100) when the head unit (200) is lowered to a certain height, if the die (300) is formed of a transparent material, additional alignment is possible through capturing the alignment marks (170, 310). In other words, alignment is possible through the alignment imaging unit (330) even when the head unit (200) is as close as possible to the stage unit (100).

[0059] In the above, it has been described that alignment is performed in the pre-alignment imaging unit (400) and then in the alignment imaging unit (330), but this is not limited thereto, and alignment may be performed only by the alignment imaging unit (330). That is, since the alignment imaging unit (330) can align at any height regardless of the position of the head unit (200), alignment may be performed at multiple positions to increase alignment precision before micro LED transfer.

[0060] Meanwhile, referring to FIG. 2, the alignment marks (170, 310) may be arranged in a pair diagonally centered on the target substrate (160) and the carrier substrate (320). The first substrate stage (140) and the die (300) have a roughly rectangular plate shape, and the alignment marks (170, 310) may be arranged diagonally at portions adjacent to the corners of the first substrate stage (140) and the die (300). Since the alignment precision with the counterpart increases as the distance between the alignment marks (170, 310) increases, the alignment marks (170, 310) are arranged diagonally in this embodiment.

[0061] Referring to FIG. 3, the alignment imaging unit (330) is installed on the upper side of the die (300) and can perform alignment by capturing an image by penetrating the die (300) made of a transparent material. The alignment imaging units (330) can be respectively positioned at positions corresponding to the alignment marks (170, 310). In the present embodiment, the alignment imaging units (330) are respectively positioned on both sides of the die (300), but this is not limited thereto, and a plurality of them can be positioned in various ways depending on the alignment position.

[0062] Referring to FIG. 4, the first substrate stage (140) may be provided with one first alignment mark (170), and the die (300) may be provided with one second alignment mark (310) corresponding to the first alignment mark (170). In this way, in the present embodiment, the alignment marks (170, 310) may not be provided in multiple numbers, but may be provided only in one. That is, alignment of the target substrate (160) and the carrier substrate (320) is possible based on one point rather than multiple points.

[0063] FIG. 5a and FIG. 5b are drawings showing another example of a substrate stage on which a target substrate is placed.

[0064] Referring to FIGS. 5A and 5B, a plurality of target substrates (160) can be arranged in a plurality of rows and columns on the first substrate stage (140). For example, if the display is 5 inches or larger, micro LED transfer must be performed multiple times. In this case, since alignment cannot be performed based on the first alignment mark (170) arranged diagonally as illustrated in FIG. 3, alignment can be performed based on one of the plurality of target substrates (160).

[0065] For example, as shown in FIGS. 5A and 5B, one or more first alignment marks (170) may be provided around a target substrate (160) positioned on the outer side of the target substrate (160). In this way, alignment may be performed based on one target substrate (160), and the remaining target substrates (160) may be aligned through separate calculations.

[0066] Fig. 6 is a drawing showing a pre-aligned imaging unit coupled to a guide rail unit, Fig. 7 is a drawing schematically showing the arrangement position of the guide rail unit, Fig. 8 is a drawing showing a side structure of the pre-aligned imaging unit, and Fig. 9 is a perspective view showing an internal cross-section of the pre-aligned imaging unit.

[0067] Referring to Fig. 6, a pair of guide rail parts (500) for movement of a pre-alignment imaging unit (400) is installed on the base (1). The guide rail parts (500) may be installed to be fixed to the lower surface of the upper base (30) of the base (1), for example.

[0068] In this embodiment, the guide rail portions (500) may be arranged in pairs on both sides with the head portion (200) as the center, as shown in FIG. 7. In FIG. 7, when the stage portion (100) that moves relative to the head portion (200) is referred to as a movable body, the guide rail portions (500) are arranged on both sides with the head portion (200) as the center, which is a fixed body. If the head portion (200) functions as a movable body and the stage portion (100) is a fixed body, the guide rail portions (500) may be arranged on both sides of the stage portion (100).

[0069] As described above, the guide rail portion (500) is arranged on both sides of the head portion (200) or the stage portion (100) to prevent the pre-alignment imaging portion (400) that moves forward and backward between the head portion (200) and the stage portion (100) from changing height due to sagging, heat, etc. during the movement process, thereby reducing the precision of the alignment. In other words, the purpose is to prevent the optical axis from being misaligned due to thermal deformation caused by the load or the surrounding environment (high temperature) during the movement process of the pre-alignment imaging portion (400). If the pre-alignment imaging portion (400) moves while being supported by the guide rail portion (500) that is arranged in parallel, sagging due to load or thermal deformation does not occur, and it is possible to move at a constant height.

[0070] Referring again to FIG. 6, a rail plate (510) is installed between the guide rail portions (500) and is moved while being supported on both sides by the guide rail portions (500), and the pre-alignment imaging unit (400) can be coupled to the rail plate (510). In this drawing, the pre-alignment imaging unit (400) is illustrated as being supported using the rail plate (510) as an intermediate medium, but a structure in which the pre-alignment imaging unit (400) itself is directly supported on both sides by the guide rail portion (500) is also possible.

[0071] An image pickup mounting unit (530) is coupled to one side, i.e., the lower surface, of the rail plate (510), and the pre-aligned image pickup unit (400) can be coupled to the rail plate (510) via the image pickup mounting unit (530). Of course, the pre-aligned image pickup unit (400) can also be directly coupled to the rail plate (510) without being coupled to the rail plate (510) via the image pickup mounting unit (530).

[0072] Referring to FIGS. 8 and 9, the pre-aligned imaging unit (400) may include an imaging body (410) coupled to an imaging unit mounting unit (530), and a camera housing (420) provided on one side of the imaging body (410) and capturing a target substrate (160) and a carrier substrate (320).

[0073] The imaging body (410) may be, for example, a pair of parallel arrangements, and a camera housing (420) may be connected to the tip. The imaging body (410) may be, for example, formed in a tube shape. A camera for imaging may be arranged inside the camera housing (420).

[0074] The camera housing (420) is provided with a catch (430) that catches the front or rear of the imaging unit mounting unit (530), and the imaging body (410) may have a width smaller than the catch (430). Since the catch (430) is a portion that extends rearward from the rear of the camera housing (420) and has a width larger than the imaging body (410), it is possible to regulate the front-rear position of the pre-align imaging unit (400).

[0075] The imaging unit mounting unit (530) is coupled to one side, i.e., the lower surface, of the rail plate (510), and can be arranged in pairs spaced apart in the front-back direction to stably support the imaging body (410) that is arranged long in the front-back direction. In addition, the imaging unit mounting unit (530) can support the imaging body (410) by forming a penetrating portion corresponding to the shape of the imaging body (410).

[0076] The catch (430) may be caught on the front or rear of the imaging unit mounting unit (530) as described above. In addition, the catch (430) may be caught on a catch protrusion (540) formed on the inside of the imaging unit mounting unit (530) as shown in FIGS. 8 and 9. The catch protrusion (540) may be formed by recessing a certain depth from the front to the rear of the imaging unit mounting unit (530), for example. When the catch (430) is caught on the catch protrusion (540) in this way, not only the front-rear position of the pre-aligned imaging unit (400) is regulated, but also the up-down position is regulated, so that the pre-aligned imaging unit (400) can be supported more stably.

[0077] Fig. 10 is a longitudinal cross-sectional view showing an example of a combined structure of a pre-aligned imaging unit and an imaging unit mounting unit, and Fig. 11 is a longitudinal cross-sectional view showing the second housing in Fig. 10 rotated downward.

[0078] Referring to FIG. 10, the imaging unit mounting unit (530) may include a first mounting housing (531) that is coupled to one surface of a rail plate (510) and has a first mounting surface (532) formed on the inside thereof on which a pre-aligned imaging unit (400) is mounted, and a second mounting housing (535) that is hinge-coupled to one side of the first mounting housing (531) and is coupled to the first mounting housing (531) in a state in which the pre-aligned imaging unit (400) is mounted on the first mounting housing (531).

[0079] The first mounting housing (531) is a part that is directly coupled to the lower surface of the rail plate (510), and a first mounting surface (532) corresponding to a tube-shaped imaging body (410) is formed on the inner side. The first mounting surface (532) and the second mounting surface (536) come into contact with the outer surface of the imaging body (410), and the first mounting surface (532) and the second mounting surface (536) may each have a hemispherical cross-section.

[0080] Meanwhile, a hinge portion (550) is provided on one side of the first mounting housing (531) and the second mounting housing (535). One end of the hinge portion (550) is connected to one side of the first mounting housing (531) and the other end is connected to one side of the second mounting housing (535), thereby connecting one side of the first mounting housing (531) and the second mounting housing (535) to each other.

[0081] Referring to Fig. 11, the operator can release the coupling of the second mounting housing (535) to mount the pre-alignment imaging unit (400) and rotate it downward about the hinge portion (550) as shown in Fig. 11. In this state where the second mounting housing (535) is rotated downward, the operator can rotate the second mounting housing (535) upward again while keeping the imaging body (410) of the pre-alignment imaging unit (400) in close contact with the first mounting surface (532) and then couple it to the first mounting housing (531).

[0082] Fig. 12 is a cross-sectional view showing another example of the combined structure of a pre-aligned imaging unit and an imaging unit mounting unit.

[0083] In this embodiment, unlike the above-described embodiment, fastening members (560) may be integrally provided on both sides of the first mounting housing (531). The operator may place the pre-aligned imaging unit (400) on the first mounting housing (531), press the second mounting housing (535) against the first mounting housing (531), and then fasten the second mounting housing (535) to the second mounting housing (535) from both sides by means of screw fastening, etc.

[0084] Alternatively, fastening members (560) may be arranged on both sides of the first mounting housing (531) and the second mounting housing (535). The fastening members (560) may be made of a separate material, and after the pre-alignment imaging unit (400) and the second mounting housing (535) are coupled to the first mounting housing (531), they may be fastened to the first mounting housing (531) and the second mounting housing (535) from both sides by means of screw fastening, etc.

[0085] Below, the operation process of the micro LED transfer device according to the present invention having the configuration described above is described.

[0086] FIG. 13 is a side view illustrating a pre-alignment imaging unit moving forward for alignment according to one embodiment of the present invention, FIG. 14 is a side view illustrating a pre-alignment imaging unit moving backward after alignment according to one embodiment of the present invention, and FIG. 15 is a side view illustrating a alignment imaging unit moving down for alignment according to one embodiment of the present invention.

[0087] Referring to FIG. 13, the pre-alignment imaging unit (400) moves forward between the head unit (200) and the stage unit (100) to align the target substrate (160) and the carrier substrate (320). At this time, the pre-alignment imaging unit (400) moves while being supported along the guide rail units (500) arranged on both sides with the head unit (200) as the center, so that sagging due to the load can be prevented. The pre-alignment imaging unit (400) can align the target substrate (160) on the lower side and the carrier substrate (320) on the upper side by imaging them, respectively.

[0088] Referring to Fig. 14, when alignment by the pre-alignment imaging unit (400) is completed, the pre-alignment imaging unit (400) moves backward and falls out between the head unit (200) and the stage unit (100). In this way, the space between the head unit (200) and the stage unit (100) is secured for transfer of the micro LED.

[0089] Referring to Fig. 15, the head unit (200) is lowered for transfer of the micro LED. At this time, the carrier substrate (320) installed on the head unit (200) is also lowered. Meanwhile, since a problem of misalignment may occur during the process of lowering the head unit (200), alignment may be additionally performed while the head unit (200) is lowered close to the stage unit (100). At this time, the alignment may be performed by the alignment imaging unit (330) capturing the first alignment mark (170) and the second alignment mark (310). Since the die (300) is made of a transparent material, the alignment imaging unit (330) can capture images from the upper portion of the die (300) toward the stage unit (100).

[0090] Next, when the laser head (220) irradiates the carrier substrate (320) with laser light, a blister is generated on the carrier substrate (320) due to the energy of the laser light. Due to the dynamic energy caused by the blister generated on the carrier substrate (320), the micro LED chip is separated from the carrier substrate (320) and transferred to the target substrate (160).

[0091] As described above, in one embodiment, alignment may be performed only in the alignment imaging unit (330) without performing alignment in the pre-alignment imaging unit (400).

[0092] Although the present invention has been described above with reference to specific embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

[0093] [Explanation of symbols]

[0094] 1: Base 10: Lower Base

[0095] 20: Side base 30: Upper base

[0096] 100: Stage section 110: Base stage

[0097] 120: First Moving Stage 130: Second Moving Stage

[0098] 140: First substrate stage 150: Second substrate stage

[0099] 160: Target substrate 170: First alignment mark

[0100] 200: Head part 210: Head plate

[0101] 220: Laser head 300: Die

[0102] 310: Second alignment mark 320: Carrier substrate

[0103] 330: Alignment imaging unit 400: Pre-alignment imaging unit

[0104] 410: Camera body 420: Camera housing

[0105] 430: Hook part 500: Guide rail part

[0106] 510: Rail plate 530: Image pickup mounting unit

[0107] 531: First mounting housing 532: First mounting surface

[0108] 535: Second mounting housing 536: Second mounting surface

[0109] 540: catch 550: hinge

[0110] 560: Fastening member 600: Control unit

Claims

1. Stage section where the target substrate is mounted; A die made of a transparent material and having a carrier substrate with a micro LED chip fixed thereon; An alignment imaging unit that captures alignment marks provided on the stage unit and the die to align the target substrate and the carrier substrate; A laser head for irradiating laser light onto the carrier substrate; and A micro LED transfer device including a control unit that controls the operation of the stage unit, the alignment imaging unit, and the laser head.

2. In paragraph 1, The above die is a micro LED transfer device made of quartz material.

3. In paragraph 1, A micro LED transfer device in which the alignment marks are arranged in a pair diagonally centered on the target substrate and the carrier substrate.

4. In paragraph 3, The above alignment mark is, A first alignment mark provided on the above stage portion; and A micro LED transfer device including a second alignment mark provided on the die.

5. In paragraph 1, A micro LED transfer device in which the die and the laser head are installed in a head section, and the head section is raised and lowered relative to the stage section.

6. In paragraph 5, The above alignment imaging unit is a micro LED transfer device that performs alignment by capturing an image while the head unit is lowered for transferring the micro LED chip.

7. In paragraph 1, A micro LED transfer device in which the target substrates are arranged in a plurality of columns and rows on the stage section, and the alignment marks are provided on the periphery of the target substrates arranged on the outside.

8. In paragraph 7, The above alignment mark is a micro LED transfer device having two alignment marks provided around the periphery of the target substrate.

9. In paragraph 1, A micro LED transfer device further comprising a pre-alignment imaging unit that is movably installed between the stage unit and the die and captures images of the target substrate and the carrier substrate to align them.

10. In paragraph 9, A micro LED transfer device further comprising a pair of guide rail sections that are movably installed while supporting both sides of the above-described pre-aligned imaging section.

Images