Assembly chamber for self-assembly of semiconductor light emitting devices

Abstract

The present invention relates to a manufacturing method of a display device, and more particularly, to an assembly chamber for self-assembly of micro-LEDs. The present invention provides an assembly chamber formed to accommodate a fluid. The assembly chamber is characterized by including a bottom, a sidewall portion configured to be formed on the bottom at a prescribed height, surrounding the bottom, and a partition wall portion formed on the bottom to be extended from a certain one of a plurality of inner sides of the sidewall portion to another inner side opposite to the certain one, at least a portion of the partition wall portion being formed to be variable in vertical height with respect to the bottom.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a display device, and in particular to an assembly chamber for self-assembly of micro light emitting diodes. Background Art

[0002] In recent years, liquid crystal displays (LCDs), organic light emitting device (OLED) displays, and micro LED (light emitting diode) displays have been competing to achieve large-area displays in the field of display technology.

[0003] On the other hand, using semiconductor light-emitting devices (micro-LEDs (uLEDs)) with a diameter or cross-sectional area of ​​100 microns or less in displays can provide very high efficiency because they do not require polarizers or other light-absorbing materials. However, large displays require millions of these devices, which makes them difficult to transfer compared to other technologies.

[0004] Transfer processes currently under development include pick and place, laser lift-off (LLO), and self-assembly. Self-assembly, in which semiconductor light-emitting devices autonomously locate themselves within a fluid, is the most promising approach for large-screen display devices.

[0005] In recent years, U.S. Patent No. 9,825,202 discloses a micro-LED structure suitable for self-assembly. However, the technology for manufacturing displays through the self-assembly of micro-LEDs remains insufficiently researched. Therefore, the present invention proposes a novel manufacturing apparatus capable of self-assembly of micro-LEDs. Summary of the Invention

[0006] Problems to be solved by the invention

[0007] An object of the present invention is to provide a new manufacturing process with high reliability for large-screen displays using micron-sized semiconductor light-emitting devices.

[0008] Another object of the present invention is to provide an assembly chamber that enables a substrate to be freely moved in various areas of the chamber while being immersed in a fluid.

[0009] Technical solutions to problems

[0010] To achieve the above-mentioned object, the present invention provides an assembly chamber configured to accommodate a fluid. The assembly chamber is characterized by comprising: a bottom; a sidewall portion configured to be formed on the bottom at a predetermined height and surrounding the bottom; and a partition wall portion formed on the bottom and extending from one of a plurality of inner side surfaces of the sidewall portion to another inner side surface opposite the one inner side surface, wherein at least a portion of the partition wall portion is formed so that its vertical height relative to the bottom can be varied.

[0011] In one embodiment, the partition wall portion includes: a frame portion fixed to the bottom portion; and a gate portion formed to be movable along one side of the frame portion, and the height of at least a portion of the partition wall portion can change with the movement of the gate portion.

[0012] In one embodiment, the gate portion can be switched from one of a first state at a first height relative to the bottom and a second state at a second height lower than the first height to another state.

[0013] In one embodiment, the gate portion may be in close contact with the frame portion in the first state.

[0014] In one embodiment, the gate portion, in a state of being in close contact with the frame portion, may be first spaced apart from the frame portion by a predetermined distance and then switched to the second state.

[0015] In one embodiment, a sealing portion may be further included, and the sealing portion is arranged on a surface of the gate portion that is in close contact with the frame portion.

[0016] In one embodiment, a water level sensor may be further included, wherein the water level sensor is configured to sense a water level of the contained fluid.

[0017] In one embodiment, the present invention may further include: a fluid supply portion, arranged at at least one of the bottom and the side wall portion, to supply fluid to the assembly chamber; and a fluid discharge portion, arranged at at least one of the bottom and the side wall portion, to discharge the contained fluid to the outside.

[0018] In one embodiment, the present invention may further include an ultrasonic instrument, which is disposed on at least one of the bottom portion and the side wall portion and vibrates the contained fluid at a predetermined frequency.

[0019] In one embodiment, at least a portion of the bottom portion may be formed of a light-transmitting layer.

[0020] Effects of the Invention

[0021] According to the present invention having the above configuration, a large number of semiconductor light emitting devices can be assembled at once in a display device in which individual pixels are formed by micro light emitting diodes.

[0022] As described above, according to the present invention, a large number of semiconductor light-emitting devices can be pixelated on a small-sized wafer and then transferred to a large-area substrate, thereby manufacturing a large-area display device at a low cost.

[0023] In addition, according to the present invention, since the magnetic field and electric field in the solution are used to simultaneously transfer a large number of semiconductor light-emitting devices to accurate positions, low-cost, high-efficiency, and high-speed transfer can be achieved regardless of the size or number of components and the transfer area.

[0024] Furthermore, since the assembly is based on an electric field, selective assembly can be achieved by selectively applying electricity, without the need for additional equipment or processes. Furthermore, since the assembly substrate is positioned on the upper side of the chamber, loading and unloading of the substrate is facilitated, and nonspecific binding of the semiconductor light-emitting device can be prevented.

[0025] In addition, according to the present invention, since the height of the partition wall portion used to divide the multiple areas set in the assembly chamber can be adjusted, the multiple semiconductor light-emitting devices floating in each area can be prevented from mixing with each other, and the substrate can move freely in each area in a state immersed in the fluid. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a conceptual diagram showing an embodiment of a display device using a semiconductor light-emitting device according to the present invention.

[0027] Figure 2 yes Figure 1 A partial enlarged view of part A of the display device.

[0028] Figure 3 yes Figure 2 An enlarged view of a semiconductor light-emitting device.

[0029] Figure 4 It shows Figure 2 An enlarged view of another embodiment of a semiconductor light emitting device.

[0030] Figures 5a to 5e This is a conceptual diagram for explaining a new process for manufacturing the aforementioned semiconductor light-emitting device.

[0031] Figure 6 This is a conceptual diagram showing an example of a self-assembly apparatus for a semiconductor light-emitting device according to the present invention.

[0032] Figure 7 yes Figure 6 Block diagram of the self-assembly device.

[0033] Figures 8a to 8e Is shown using Figure 6 A conceptual diagram of the process of self-assembling a semiconductor light-emitting device using a self-assembly device.

[0034] Figure 9 Is used to illustrate Figures 8a to 8e Conceptual diagram of a semiconductor light-emitting device.

[0035] Figure 10 is a flow chart illustrating the self-assembly method of the present invention.

[0036] Figure 11 1 is a conceptual diagram showing a first state of the substrate chuck.

[0037] Figure 12 It is a conceptual diagram showing the second state of the substrate chuck.

[0038] Figure 13 It is a top view of the first frame provided on the substrate chuck.

[0039] Figure 14 This is a conceptual diagram showing a state where an assembled substrate is loaded on a substrate chuck.

[0040] Figure 15 FIG. 1 is a perspective view of a magnetic field forming unit according to an embodiment of the present invention.

[0041] Figure 16 FIG. 1 is a side view of a magnetic field forming unit according to an embodiment of the present invention.

[0042] Figure 17 FIG. 1 is a bottom side view of a magnetic field forming portion according to an embodiment of the present invention.

[0043] Figure 18 This is a conceptual diagram showing the loci of a plurality of magnets provided in the magnetic field forming portion of the present invention.

[0044] Figure 19 is a conceptual diagram showing a situation in which semiconductor light emitting devices are supplied.

[0045] Figure 20 FIG. 1 is a top view of an assembly chamber according to an embodiment of the present invention.

[0046] Figure 21 It is along Figure 20 A cross-sectional view taken along line AA'.

[0047] Figure 22 FIG. 1 is a perspective view of an assembly chamber according to an embodiment of the present invention.

[0048] Figure 23 and Figure 24is a conceptual diagram showing an assembly chamber having a buffer area.

[0049] Figure 25 is a conceptual diagram showing an assembly chamber including a shutter portion.

[0050] Figure 26 This is an enlarged view of a gate portion provided in the assembly chamber of the present invention.

[0051] Figure 27 This is a conceptual diagram emphasizing the bottom and sidewall portions of the assembly chamber of the present invention.

[0052] Figure 28 This is a conceptual diagram emphasizing the gate portion of the present invention.

[0053] Figure 29 and Figure 30 It is a conceptual diagram showing the change in height of the partition wall portion.

[0054] Figures 31 to 33 This is a conceptual diagram emphasizing a plurality of components provided in the assembly chamber of the present invention. DETAILED DESCRIPTION

[0055] Below, the embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings. Regardless of the figure symbols, the same or similar constituent elements are given the same figure symbols, and repeated descriptions of this will be omitted. The suffixes "module" and "section" of the constituent elements used in the following description are given or mixed only for the sake of ease of writing the specification, and they themselves do not have meanings or functions that distinguish each other. In addition, when describing the embodiments disclosed in this specification, if it is judged that a detailed description of the relevant known technology may confuse the main purpose of the embodiments disclosed in this specification, its detailed description will be omitted. In addition, it should be understood that the drawings are only used to make the embodiments disclosed in this specification easy to understand, and the technical ideas disclosed in this specification are not limited by the drawings.

[0056] Furthermore, when an element such as a layer, a region or a substrate is referred to as being “on” another element, it should be understood that it can be directly on the other element or intervening elements may be present therebetween.

[0057] The display devices described in this specification may include mobile phones, smart phones, laptop computers, digital broadcast terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigators, touchscreen tablet PCs (Slate PCs), tablet PCs (Tablet PCs), Ultrabooks, digital TVs, digital signage, head-mounted displays (HMDs), desktop computers, and the like. However, it will be readily understood by those skilled in the art that the configurations of the embodiments described in this specification may also be applied to devices capable of displaying a display, even in the form of new products developed subsequently.

[0058] Figure 1 FIG. 1 is a conceptual diagram showing an embodiment of a display device using a semiconductor light emitting device according to the present invention. Figure 2 yes Figure 1 A partial enlarged view of part A of the display device, Figure 3 yes Figure 2 An enlarged view of a semiconductor light-emitting device. Figure 4 It shows Figure 2 An enlarged view of another embodiment of a semiconductor light emitting device.

[0059] According to the drawings, information processed by the control unit of the display device 100 can be output to the display module 140. The housing 101 in a closed loop surrounding the edge of the display module 140 can form a frame of the display device 100.

[0060] The display module 140 includes a panel 141 for displaying an image. The panel 141 may include a micron-sized semiconductor light emitting device 150 and a wiring substrate 110 for mounting the semiconductor light emitting device 150 .

[0061] Wiring is formed on the wiring substrate 110, thereby connecting to the n-type electrode 152 and the p-type electrode 156 of the semiconductor light emitting device 150. Thus, the semiconductor light emitting device 150 can be provided on the wiring substrate 110 as a single pixel that emits light independently.

[0062] The image displayed on the panel 141 is visual information, and is independently controlled by the wiring, thereby realizing light emission of unit pixels (sub-pixels) arranged in a matrix form.

[0063] In the present invention, a micro-LED (Light Emitting Diode) is shown as one type of semiconductor light-emitting device 150 for converting current into light. The micro-LED can be a small-sized light-emitting diode with a size of less than 100 microns. The semiconductor light-emitting device 150 is provided with blue, red, and green light-emitting regions, respectively, so that a unit pixel can be realized by combining these light-emitting devices. In other words, the unit pixel is the smallest unit for realizing a single color, and at least three micro-LEDs can be provided within the unit pixel.

[0064] More specifically, refer to Figure 3 , the semiconductor light emitting device 150 may be a vertical structure.

[0065] For example, the semiconductor light emitting device 150 may be implemented as a high-output light emitting device that adds indium (In) and / or aluminum (Al) to gallium nitride (GaN) to emit various lights including blue.

[0066] This vertical semiconductor light-emitting device includes a p-type electrode 156; a p-type semiconductor layer 155 formed on the p-type electrode 156; an active layer 154 formed on the p-type semiconductor layer 155; an n-type semiconductor layer 153 formed on the active layer 154; and an n-type electrode 152 formed on the n-type semiconductor layer 153. In this case, the p-type electrode 156, located at the bottom, can be electrically connected to the p-electrode of the wiring substrate, while the n-type electrode 152, located at the top, can be electrically connected to the n-electrode on the upper side of the semiconductor light-emitting device. This vertical semiconductor light-emitting device 150 can have electrodes arranged in an up / down configuration, thus offering a significant advantage in reducing chip size.

[0067] As another example, refer to Figure 4 , the semiconductor light emitting device may be a flip chip type light emitting device.

[0068] As an example, the semiconductor light-emitting device 150' includes: a p-type electrode 156'; a p-type semiconductor layer 155' having p-type electrode 156' formed thereon; an active layer 154' formed on p-type semiconductor layer 155'; an n-type semiconductor layer 153' formed on active layer 154'; and an n-type electrode 152' disposed on n-type semiconductor layer 153' and spaced horizontally from p-type electrode 156'. In this case, both p-type electrode 156' and n-type electrode 152' can be electrically connected to the p-electrode and n-electrode of the wiring substrate at the bottom of the semiconductor light-emitting device.

[0069] The vertical semiconductor light-emitting device and the horizontal semiconductor light-emitting device can be a green semiconductor light-emitting device, a blue semiconductor light-emitting device or a red semiconductor light-emitting device, respectively. In the case of a green semiconductor light-emitting device and a blue semiconductor light-emitting device, they can be realized by a high-output light-emitting device, which adds indium (In) and / or aluminum (Al) to gallium nitride (GaN) to emit green or blue light. As an example, the semiconductor light-emitting device can be a gallium nitride thin film formed by various layers such as n-Gan, p-Gan, AlGaN, InGan, etc. Specifically, the p-type semiconductor layer can be P-type GaN, and the n-type semiconductor layer can be N-type GaN. However, in the case of a red semiconductor light-emitting device, the p-type semiconductor layer can be P-typeGaAs, and the n-type semiconductor layer can be N-type GaAs.

[0070] Furthermore, the p-type semiconductor layer may be formed of P-type GaN doped with Mg on the p-electrode side, and the n-type semiconductor layer may be formed of N-type GaN doped with Si on the n-electrode side. In this case, the semiconductor light-emitting device may be a semiconductor light-emitting device without an active layer.

[0071] In addition, refer to Figures 1 to 4 Since the light-emitting diodes are very small, the display panel can be formed by arranging self-luminous unit pixels with high precision, thereby realizing a high-definition display device.

[0072] In the display device using semiconductor light-emitting devices of the present invention described above, a semiconductor light-emitting device grown on a wafer and formed by a mesa and isolation is used as a single pixel. In this case, the semiconductor light-emitting device 150 having a micron size needs to be transferred to the wafer at a preset position on the substrate of the display panel. As such a transfer technique, pick and place can be used, but the success rate is low and it takes a long time. As another example, there is a technique for transferring multiple devices at once using a stamp or a roll, but the yield is limited, and thus it is not suitable for large-screen displays. The present invention proposes a new manufacturing method and manufacturing device for a display device that can solve such problems.

[0073] To this end, a new method for manufacturing a display device will first be described below. Figures 5a to 5e This is a conceptual diagram for explaining a new process for manufacturing the aforementioned semiconductor light-emitting device.

[0074] This specification describes a display device using passive matrix (PM) semiconductor light-emitting devices. However, the following examples are also applicable to active matrix (AM) semiconductor light-emitting devices. Furthermore, while the following examples illustrate a method for self-assembling horizontal semiconductor light-emitting devices, this also applies to methods for self-assembling vertical semiconductor light-emitting devices.

[0075] First, according to the manufacturing method, the first conductive type semiconductor layer 153, the active layer 154, and the second conductive type semiconductor layer 155 are grown on the growth substrate 159 ( Figure 5a ).

[0076] If the first conductive type semiconductor layer 153 is grown, then the active layer 154 is grown on the first conductive type semiconductor layer 153, and then the second conductive type semiconductor layer 155 is grown on the active layer 154. As described above, if the first conductive type semiconductor layer 153, the active layer 154, and the second conductive type semiconductor layer 155 are grown in sequence, then Figure 5a As shown, the first conductive type semiconductor layer 153 , the active layer 154 and the second conductive type semiconductor layer 155 form a stacked structure.

[0077] In this case, the first conductive type semiconductor layer 153 may be a p-type semiconductor layer, and the second conductive type semiconductor layer 155 may be an n-type semiconductor layer. However, the present invention is not necessarily limited thereto, and the first conductive type may be n-type and the second conductive type may be p-type.

[0078] Furthermore, while this embodiment illustrates the presence of the active layer, as described above, a structure without the active layer is also possible depending on the situation. For example, the p-type semiconductor layer is P-type GaN doped with Mg, and the n-type semiconductor layer is N-type GaN doped with Si on the n-electrode side.

[0079] The growth substrate 159 (wafer) can be formed of a light-transmitting material, such as, but not limited to, sapphire (Al2O3), GaN, ZnO, or AlO. Furthermore, the growth substrate 159 can be formed of a carrier wafer, which is a material suitable for growing semiconductor materials. It can be formed of a material with excellent thermal conductivity, including a conductive substrate or an insulating substrate. For example, a SiC substrate, which has higher thermal conductivity than a sapphire (Al2O3) substrate, or at least one of Si, GaAs, GaP, InP, and Ga2O3 can be used.

[0080] Next, a plurality of semiconductor light emitting devices ( Figure 5b ).

[0081] More specifically, isolation is performed so that the plurality of light emitting devices form a light emitting device array. That is, the first conductive type semiconductor layer 153, the active layer 154, and the second conductive type semiconductor layer 155 are etched in a vertical direction, thereby forming a plurality of semiconductor light emitting devices.

[0082] Assuming that a horizontal semiconductor light-emitting device is to be formed, a table process can be performed to remove a portion of the active layer 154 and the second conductive semiconductor layer 155 in the vertical direction to expose the first conductive semiconductor layer 153 to the outside, and then isolation (isolation) of a plurality of semiconductor light-emitting device arrays can be formed by etching the first conductive semiconductor layer.

[0083] Then, a second conductive type electrode 156 (or a p-type electrode) is formed on one surface of the second conductive type semiconductor layer 155. Figure 5c The second conductive type electrode 156 can be formed by a deposition method such as sputtering, but the present invention is not necessarily limited thereto. However, if the first conductive type semiconductor layer and the second conductive type semiconductor layer are n-type semiconductor layers and p-type semiconductor layers, respectively, the second conductive type electrode 156 can also be an n-type electrode.

[0084] Then, a plurality of semiconductor light emitting devices are formed by removing the growth substrate 159. For example, the growth substrate 159 can be removed by using a laser lift-off (LLO) or a chemical lift-off (CLO). Figure 5d ).

[0085] Then, a step of placing a plurality of semiconductor light emitting devices 150 on a substrate is performed in a chamber filled with a fluid ( Figure 5e ).

[0086] For example, the semiconductor light emitting device 150 and the substrate are placed in a chamber filled with fluid, and the semiconductor light emitting device is autonomously assembled to the substrate 161 using flow, gravity, surface tension, etc. In this case, the substrate may be the assembly substrate 161 .

[0087] As another example, a wiring substrate may be placed in the assembly chamber instead of the assembly substrate 161, so that the semiconductor light-emitting device 150 is directly mounted on the wiring substrate. In this case, the substrate may be the wiring substrate. However, for ease of description, the present invention illustrates a case where the substrate is the assembly substrate 161 and a plurality of semiconductor light-emitting devices 1050 are mounted thereon.

[0088] The assembly substrate 161 may be provided with a plurality of cells (not shown) into which the plurality of semiconductor light-emitting devices 150 are inserted, thereby facilitating placement of the plurality of semiconductor light-emitting devices 150 on the assembly substrate 161. Specifically, cells are formed on the assembly substrate 161 at positions where the semiconductor light-emitting devices 150 are aligned with the wiring electrodes, and the semiconductor light-emitting devices 150 are placed in the cells. The semiconductor light-emitting devices 150 are assembled into the cells while moving within the fluid.

[0089] After the semiconductor light emitting devices are arrayed in the assembly substrate 161 , when the semiconductor light emitting devices of the assembly substrate 161 are transferred to a wiring substrate, a large area transfer can be achieved. Therefore, the assembly substrate 161 can be called a temporary substrate.

[0090] In addition, if the self-assembly method described above is to be applied to the manufacture of large-screen displays, it is necessary to improve the transfer yield rate. In order to improve the transfer yield rate, the present invention proposes a method and device that minimizes the influence of gravity or friction and prevents nonspecific binding.

[0091] In this case, in the display device of the present invention, a magnetic body is placed on a semiconductor light-emitting device and the semiconductor light-emitting device is moved using magnetic force. During the movement, the semiconductor light-emitting device is positioned at a predetermined position using an electric field. This transfer method and device will be described in further detail below with reference to the accompanying drawings.

[0092] Figure 6 1 is a conceptual diagram showing an example of a self-assembly apparatus for a semiconductor light-emitting device according to the present invention. Figure 7 yes Figure 6 A block diagram of a self-assembly device. And, Figures 8a to 8e Is shown using Figure 6 A conceptual diagram of the process of self-assembling a semiconductor light-emitting device using a self-assembly device. Figure 9 Is used to illustrate Figures 8a to 8e Conceptual diagram of a semiconductor light-emitting device.

[0093] like Figure 6 and Figure 7As shown, the self-assembly device 160 of the present invention may include an assembly chamber 162 , a magnet 163 and a position control unit 164 .

[0094] The assembly chamber 162 has a space for accommodating a plurality of semiconductor light-emitting devices. The space may be filled with a fluid, such as water, as an assembly solution. Thus, the assembly chamber 162 may be a water tank and may be open. However, the present invention is not limited thereto, and the assembly chamber 162 may be a closed space.

[0095] The substrate 161 can be positioned in the assembly chamber 162 with its assembly surface for assembling the semiconductor light-emitting device 150 facing downward. For example, the substrate 161 is moved to the assembly position by a transfer unit, which can include a stage 165 on which the substrate is mounted. The stage 165 can be adjusted in position by a control unit, thereby allowing the substrate 161 to be moved to the assembly position.

[0096] At this time, the assembly surface of the substrate 161 faces the bottom of the assembly chamber 162 in the assembly position. As shown in the figure, the assembly surface of the substrate 161 is configured to be immersed in the fluid in the assembly chamber 162. Therefore, the semiconductor light emitting device 150 moves toward the assembly surface within the fluid.

[0097] The substrate 161 is an assembly substrate capable of forming an electric field, and may include a base portion 161 a , a dielectric layer 161 b , and a plurality of electrodes 161 c .

[0098] The base portion 161a may be made of an insulating material, and the plurality of electrodes 161c may be thin-film or thick-film bi-planar electrodes patterned on one surface of the base portion 161a. For example, the electrodes 161c may be formed of a Ti / Cu / Ti stack, Ag paste, and ITO.

[0099] The dielectric layer 161b can be made of inorganic materials such as SiO2, SiNx, SiON, Al2O3, TiO2, HfO2, etc. In contrast, the dielectric layer 161b, as an organic insulator, can be made of a single layer or multiple layers. The thickness of the dielectric layer 161b can be formed to a thickness of tens of nm to several μm.

[0100] Furthermore, the substrate 161 of the present invention includes a plurality of cells 161d divided by partition walls. The cells 161d are arranged sequentially along a direction and can be made of a polymer material. Furthermore, the partition walls 161e forming the cells 161d are shared with adjacent cells 161d. The partition walls 161e protrude from the base portion 161a, and the cells 161d can be arranged sequentially along a direction via the partition walls 161e. More specifically, the cells 161d are arranged sequentially in the column direction and the row direction, respectively, and can have a matrix structure.

[0101] As shown, a groove for accommodating the semiconductor light-emitting device 150 is provided within the cell 161d. This groove can be the space defined by the partition wall 161e. The shape of the groove can be the same as or similar to that of the semiconductor light-emitting device. For example, if the semiconductor light-emitting device is square, the groove can be square. Furthermore, although not shown, if the semiconductor light-emitting device is circular, the groove formed within the cell can also be circular. Furthermore, each cell is configured to accommodate a single semiconductor light-emitting device. That is, one semiconductor light-emitting device is housed within each cell.

[0102] On the other hand, the plurality of electrodes 161c are provided with a plurality of electrode lines arranged at the bottom of each unit cell 161d, and the plurality of electrode lines may be configured to extend toward adjacent units.

[0103] A plurality of electrodes 161c are arranged on the underside of each cell 161d, and by applying different polarities to each of them, an electric field is generated within each cell 161d. To form this electric field, the dielectric layer can cover the plurality of electrodes 161c and also form the bottom of each cell 161d. In this structure, when different polarities are applied to a pair of electrodes 161c on the underside of each cell 161d, an electric field is generated, and the semiconductor light-emitting device can be inserted into the interior of each cell 161d due to this electric field.

[0104] In the assembled position, the electrodes of the substrate 161 are electrically connected to the power supply unit 171. The power supply unit 171 applies power to the plurality of electrodes to generate the electric field.

[0105] As shown, the self-assembly apparatus may include a magnet 163 for applying a magnetic force to the semiconductor light-emitting device. The magnet 163 is spaced apart from the assembly chamber 162 to apply a magnetic force to the semiconductor light-emitting device 150. The magnet 163 may be positioned facing the surface opposite the assembly surface of the substrate 161, and the position of the magnet 163 may be controlled by a position control unit 164 connected to the magnet 163.

[0106] The semiconductor light emitting device 1050 may include a magnetic body so as to move within the fluid by the magnetic field of the magnet 163 .

[0107] Reference Figure 9 A semiconductor light-emitting device having a magnetic body may include: a first conductive electrode 1052 and a second conductive electrode 1056; a first conductive semiconductor layer 1053, which is configured with the first conductive electrode 1052; a second conductive semiconductor layer 1055, which overlaps with the first conductive semiconductor layer 1052 and is configured with the second conductive electrode 1056; and an active layer 1054, which is configured between the first conductive semiconductor layer 1053 and the second conductive semiconductor layer 1055.

[0108] Here, the first conductivity type can be p-type, the second conductivity type can be n-type, and vice versa. In addition, it can also be formed into a semiconductor light emitting device without the active layer as described above.

[0109] On the other hand, in the present invention, the first conductive type electrode 1052 can be formed after the semiconductor light-emitting device is assembled onto the wiring substrate through, for example, self-assembly of the semiconductor light-emitting device. Furthermore, in the present invention, the second conductive type electrode 1056 can include the magnetic material. The magnetic material can be a magnetic metal. The magnetic material can be Ni, SmCo, etc. As another example, it can also include a material corresponding to at least one of the Gd-based, La-based, and Mn-based materials.

[0110] The magnetic substance may also be provided in the form of particles on the second conductive electrode 1056. Furthermore, in a conductive electrode including a magnetic substance, one layer of the conductive electrode may be composed of a magnetic substance. As an example, Figure 9 As shown, the second conductive type electrode 1056 of the semiconductor light emitting device 1050 may include a first layer 1056a and a second layer 1056b. Here, the first layer 1056a may be formed to include a magnetic body, and the second layer 1056b may include a non-magnetic metal material.

[0111] As shown in the figure, in this embodiment, first layer 1056a, which includes a magnetic material, can be arranged in contact with second-conductivity-type semiconductor layer 1055. In this case, first layer 1056a is arranged between second layer 1056b and second-conductivity-type semiconductor layer 1055. Second layer 1056b can serve as a contact metal connected to the second electrode of the wiring substrate. However, the present invention is not necessarily limited to this, and the magnetic material can be arranged on one surface of the first-conductivity-type semiconductor layer.

[0112] Refer again Figure 6 and Figure 7 More specifically, the self-assembly device may include a magnet handler or a motor. The magnet handler may be automatically or manually moved along the x, y, and z axes at the top of the assembly chamber, and the motor may rotate the magnet 163. The magnet handler and the motor may constitute the position control unit 164. Thus, the magnet 163 rotates in a direction horizontal to the substrate 161, in a clockwise direction, or in a counterclockwise direction.

[0113] In addition, the assembly chamber 162 may be formed with a light-transmitting bottom plate 166, and the plurality of semiconductor light-emitting devices may be arranged between the bottom plate 166 and the substrate 161. An image sensor 167 may be arranged facing the bottom plate 166 to monitor the interior of the assembly chamber 162 through the bottom plate 166. The image sensor 167 is controlled by the control unit 172 and may include an inverted lens and a CCD, etc., so as to be able to observe the assembly surface of the substrate 161.

[0114] The self-assembly device described above utilizes a combination of magnetic and electric fields. When these magnetic and electric fields are utilized, the plurality of semiconductor light-emitting devices can be positioned at predetermined positions on the substrate by the electric field while being moved by the positional changes of the magnet. The assembly process using the self-assembly device described above will be described in further detail below.

[0115] First, by Figures 5a to 5c The process described in the above is to form a plurality of semiconductor light emitting devices 1050 provided with a magnetic body. In this case, when forming Figure 5c During the process of forming the second conductive type electrode, a magnetic body may be deposited onto the semiconductor light emitting device.

[0116] Next, the substrate 161 is moved to the assembly position, and the semiconductor light emitting device 1050 is placed into the assembly chamber 162 ( Figure 8a ).

[0117] As described above, the assembly position of the substrate 161 may be such that the substrate 161 is disposed in the assembly chamber 162 with the assembly surface of the substrate 161 for assembling the semiconductor light emitting device 1050 facing downward.

[0118] In this case, a portion of the semiconductor light emitting device 1050 may sink to the bottom of the assembly chamber 162, while a portion may float in the fluid. If a light-transmitting bottom plate 166 is provided in the assembly chamber 162, a portion of the semiconductor light emitting device 1050 may sink to the bottom plate 166.

[0119] Then, a magnetic force is applied to the semiconductor light emitting device 1050, so that the semiconductor light emitting device 1050 floats vertically in the assembly chamber 162 ( Figure 8b ).

[0120] When the magnet 163 of the self-assembly device moves from its original position toward the surface opposite the assembly surface of the substrate 161, the semiconductor light-emitting device 1050 floats in the fluid toward the substrate 161. The original position may be a position away from the assembly chamber 162. As another example, the magnet 163 may be an electromagnet. In this case, the initial magnetic force is generated by supplying power to the electromagnet.

[0121] In addition, in this example, the separation distance between the assembly surface of the substrate 161 and the semiconductor light-emitting device 1050 can be controlled by adjusting the magnitude of the magnetic force. For example, the separation distance can be controlled by utilizing the weight, buoyancy, and magnetic force of the semiconductor light-emitting device 1050. The separation distance can be from a few millimeters to tens of microns from the outermost edge of the substrate.

[0122] Next, a magnetic force is applied to the semiconductor light emitting device 1050, so that the semiconductor light emitting device 1050 moves in one direction within the assembly chamber 162. For example, the magnet 163 moves in a direction horizontal to the substrate, in a clockwise direction, or in a counterclockwise direction ( Figure 8c In this case, under the action of the magnetic force, the semiconductor light emitting device 1050 moves in a direction parallel to the substrate 161 at a position separated from the substrate 161 .

[0123] Next, a step is performed to guide the semiconductor light emitting device 1050 to a preset position of the substrate 161 by applying an electric field, so that the semiconductor light emitting device 1050 is positioned at the preset position during the movement ( Figure 8cFor example, while the semiconductor light emitting device 1050 is moving in a direction horizontal to the substrate 161 , the electric field causes the semiconductor light emitting device 1050 to move in a direction perpendicular to the substrate 161 , thereby placing the semiconductor light emitting device 1050 at a predetermined position on the substrate 161 .

[0124] More specifically, an electric field is generated by supplying power to the bi-planar electrodes of the substrate 161. This electric field is then used to guide the assembly process, allowing the semiconductor light-emitting devices 1050 to be assembled only at predetermined locations. In other words, the selectively generated electric field is used to autonomously assemble the semiconductor light-emitting devices 1050 to the assembly locations on the substrate 161. To this end, the substrate 161 may be provided with cells for inserting the semiconductor light-emitting devices 1050.

[0125] Then, the substrate 161 is unloaded and the assembly process is completed. In the case where the substrate 161 is an assembly substrate, the aligned semiconductor light emitting devices can be transferred to a wiring substrate, thereby enabling subsequent processes for realizing a display device.

[0126] In addition, after the semiconductor light emitting device 1050 is guided to the preset position, the magnet 163 may be moved in a direction away from the substrate 161 so that the semiconductor light emitting device 1050 remaining in the assembly chamber 162 falls to the bottom of the assembly chamber 162 ( Figure 8d As another example, in the case where the magnet 163 is an electromagnet, if the power supply is interrupted, the semiconductor light emitting device 1050 remaining in the assembly chamber 162 will fall to the bottom of the assembly chamber 162.

[0127] Then, when the semiconductor light emitting device 1050 dropped to the bottom of the assembly chamber 162 is recovered, the recovered semiconductor light emitting device 1050 can be reused.

[0128] In the self-assembly device and method described above, in order to improve the assembly yield rate in fluidic assembly, a magnetic field is used to concentrate remote components near a preset assembly position, and a separate electric field is applied to the assembly position, thereby selectively assembling components only at the assembly position. At this time, the assembly substrate is positioned above the water tank, and the assembly surface is directed downward, thereby minimizing the effect of gravity caused by the weight of the components and preventing nonspecific binding, thereby eliminating defects. In other words, in order to improve the transfer yield rate, the assembly substrate is positioned above, thereby minimizing the effect of gravity or friction and preventing nonspecific binding.

[0129] As described above, according to the present invention having the above-described configuration, in a display device in which a single pixel is formed by a semiconductor light-emitting device, a large number of semiconductor light-emitting devices can be assembled at once.

[0130] As described above, according to the present invention, a large number of semiconductor light emitting devices can be pixelated on a small-sized wafer and then transferred to a large-area substrate, thereby manufacturing a large-area display device at a low cost.

[0131] When performing the self-assembly process described above, several problems arise.

[0132] First, as the display area increases, the area of ​​the assembly substrate increases. As the area of ​​the assembly substrate increases, the phenomenon of substrate bending increases. When performing self-assembly on a bent assembly substrate, the magnetic field is not uniformly formed on the surface of the assembly substrate, making it difficult to perform self-assembly stably.

[0133] Second, the semiconductor light-emitting devices cannot be completely evenly dispersed in the fluid, and the magnetic field formed on the surface of the assembly substrate cannot be completely uniform, so the problem of the semiconductor light-emitting devices being concentrated only in a part of the assembly substrate may occur.

[0134] The present invention provides a self-assembly device, which not only solves the above problems but also can improve the self-assembly yield rate.

[0135] The self-assembly device of the present invention may include a substrate surface processing unit, a substrate chuck 200, a magnetic field forming unit 300, a chip supply unit 400, and an assembly chamber 500. However, the present invention is not limited thereto, and the self-assembly device of the present invention may include more or fewer components than the above components.

[0136] Before describing the self-assembly device of the present invention, a self-assembly method using the self-assembly device of the present invention will be briefly described.

[0137] Figure 10 is a flow chart illustrating the self-assembly method of the present invention.

[0138] First, a surface treatment step of the assembly substrate is performed (S110). This step is not essential, but when the substrate surface is made hydrophilic, it can prevent bubbles from forming on the substrate surface.

[0139] Then, the step of loading the assembled substrate onto the substrate chuck (S120) is performed. The assembled substrate loaded onto the substrate chuck 200 is moved to the assembly position of the assembly chamber. Then, the magnetic field forming unit approaches the assembled substrate by vertically and horizontally moving.

[0140] In this state, the chip supply step (S130) is performed. Specifically, the semiconductor light-emitting devices are dispersed on the assembly surface of the assembly substrate. When the semiconductor light-emitting devices are dispersed near the assembly surface with the magnetic field generating unit 300 sufficiently close to the assembly substrate, the magnetic field generating unit causes the plurality of semiconductor light-emitting devices to adhere to the assembly surface. The plurality of semiconductor light-emitting devices are dispersed on the assembly surface with an appropriate degree of dispersion.

[0141] However, the semiconductor light emitting devices may be dispersed in the fluid in the assembly chamber before the substrate is moved to the assembly position. That is, the time point for performing the chip supply step (S130) is not limited to after the assembly substrate is moved to the assembly position.

[0142] The supply method of semiconductor light emitting devices may vary depending on the area of ​​the assembly substrate, the type of semiconductor light emitting devices to be assembled, and the self-assembly speed.

[0143] Then, a step (S140) of performing self-assembly and recovering the semiconductor light-emitting device is performed. Regarding self-assembly, it will be described later together with the description of the self-assembly apparatus of the present invention. On the other hand, it is not necessary to recover the semiconductor light-emitting device after self-assembly. After the self-assembly is completed, the semiconductor light-emitting device can be replenished in the assembly chamber, and then self-assembly can be performed on a new substrate.

[0144] Finally, after the self-assembly is completed, the steps of inspecting, drying the assembled substrate and separating the substrate from the substrate chuck (S150) can be performed. The inspection of the assembled substrate can be performed at the location where the self-assembly is performed or after the assembled substrate is moved to another location.

[0145] On the other hand, the drying of the assembled substrate can be performed after the assembled substrate is separated from the fluid. After the drying of the assembled substrate, a post-assembly process can be performed.

[0146] use Figures 1 to 9 The contents described in the following replace the contents regarding the basic principles of self-assembly, the structure of the substrate (or assembly substrate), and the semiconductor light-emitting device. Meanwhile, the vertical moving portion, horizontal moving portion, rotating portion, and other moving devices described below can be implemented using well-known devices such as motors and ball screws, racks and pinions, pulleys, and timing belts, and therefore detailed descriptions are omitted.

[0147] on the other hand, Figure 7The control unit 172 described in the preceding text controls the movement of the vertical moving unit, horizontal moving unit, rotation unit, and other moving devices provided in the aforementioned components. Specifically, the control unit 172 is configured to control the movement of each component along the x-, y-, and z-axes, as well as the rotational movement. Although not specifically mentioned in this specification, the movement of the vertical moving unit, horizontal moving unit, rotation unit, and other moving devices is controlled by the control unit 172.

[0148] On the other hand, Figures 6 to 9 The electrode 161c provided on the substrate (or assembly substrate) 161 described in the embodiment is called an assembly electrode. The assembly electrode 161c is connected to the substrate chuck 200 by the substrate chuck 200. Figure 7 The power supply unit 171 is electrically connected to the assembly electrode 161c, and the power supply unit 171 supplies power to the assembly electrode 161c under the control of the control unit 172. The details will be described later.

[0149] The above-mentioned components are described below.

[0150] First, the substrate surface treatment unit hydrophilizes the substrate surface. Specifically, the self-assembly device of the present invention performs self-assembly while the assembly substrate is in contact with the fluid surface. If the assembly surface of the assembly substrate has different properties from the fluid surface, bubbles may form on the assembly surface, potentially leading to nonspecific binding between the semiconductor light-emitting device and the assembly surface. To prevent this, the substrate surface can be treated with a fluid-friendly treatment prior to self-assembly.

[0151] In one embodiment, when the fluid is a polar substance such as water, the substrate surface treatment portion can make the assembly surface of the substrate hydrophilic.

[0152] For example, the substrate surface treatment unit may include a plasma generator. Plasma treatment of the substrate surface may form a plurality of hydrophilic functional groups on the substrate surface. Specifically, the plasma treatment may form a plurality of hydrophilic functional groups on at least one of a partition wall and a dielectric layer provided on the substrate.

[0153] Alternatively, the surface of the partition wall and the surface of the dielectric layer exposed to the outside through the cell can be treated differently to prevent nonspecific binding of the semiconductor light-emitting device. For example, the surface of the dielectric layer exposed to the outside through the cell can be treated to be hydrophilic, while the surface of the partition wall can be treated to form hydrophobic functional groups. This prevents nonspecific binding of the semiconductor light-emitting device to the surface of the partition wall, allowing the semiconductor light-emitting device to be securely fixed within the cell.

[0154] However, the substrate surface treatment unit is not an essential component of the self-assembly device of the present invention and may not be necessary depending on the constituent materials forming the substrate.

[0155] The substrate having been surface-processed by the substrate surface processing unit is loaded onto the substrate chuck 200 .

[0156] Next, the substrate chuck 200 will be described.

[0157] Figure 11 is a conceptual diagram showing a first state of the substrate chuck, Figure 12 is a conceptual diagram showing a second state of the substrate chuck, Figure 13 is a top view of the first frame provided on the substrate chuck, Figure 14 This is a conceptual diagram showing a state where an assembled substrate is loaded on a substrate chuck.

[0158] Referring to the accompanying drawings, the substrate chuck 200 includes a substrate supporting portion. In one embodiment, the substrate supporting portion includes a first frame 210, a second frame 220, and a fixing portion 230. The first frame 210 and the second frame 220 are arranged vertically with the loaded substrate interposed therebetween, and the fixing portion 230 supports the first frame 210 and the second frame 220. The substrate chuck 200 may include a rotating portion 240, a vertical moving portion, and a horizontal moving portion 250. Figure 11 As shown, the vertical moving part and the horizontal moving part 250 can be composed of one device. On the other hand, the rotating part, the vertical moving part and the horizontal moving part provided on the substrate chuck can be composed of one device without being limited to the drawings described below.

[0159] In this specification, the first frame 210 is defined as a frame arranged on the lower side of the substrate when the assembly surface of the substrate S faces the fluid, and the second frame 220 is defined as a frame arranged on the upper side of the substrate when the assembly surface of the substrate faces the fluid. Due to the rotating part 240, the upper and lower relationships of the first frame 210 and the second frame 220 can be converted to each other. In this specification, the state in which the first frame 210 is located below the second frame 220 is defined as the first state (refer to Figure 11 ), the state where the first frame 210 is located above the second frame 220 is defined as the second state (refer to Figure 12 The rotating portion 240 switches from the first state to the second state by rotating at least one of the first frame 210, the second frame 220, and the fixing portion 230. The rotating portion 240 will be described later.

[0160] The first frame 210 is a frame that contacts the fluid filled in the assembly chamber during self-assembly. Figure 14 The first frame 210 includes a bottom portion 210 ′ and a side wall portion 210 ″.

[0161] When the substrate S is loaded, the bottom portion 210' plays a role in supporting the substrate at the lower side or the upper side of the substrate S. The bottom portion 210' may be formed of a single plate shape, or may be formed in a form in which a plurality of plate-shaped members are combined. Figure 13 , the bottom 210' has a hole 210'"' running through the central portion. The hole 210'" exposes a substrate to be described later to the outside so as to come into contact with the fluid. That is, the hole 210'" defines the assembly surface of the substrate. The substrate is loaded so that the four corners of the quadrilateral substrate are stuck to the edges of the hole 210'" of the first frame 210. Thus, the remaining area except the edge of the substrate overlaps with the hole 210'" provided in the first frame 210. The area of ​​the substrate overlapping with the hole 210'" becomes the assembly surface.

[0162] On the other hand, a sealing portion 212 and an electrode connecting portion 213 may be disposed at the edge of the hole 210 ″.

[0163] The sealing portion 212 is tightly attached to the substrate to prevent the fluid filled in the assembly chamber during self-assembly from penetrating into the first frame 210 and the second frame 220. In addition, the sealing portion 212 prevents the fluid from penetrating into the assembly electrode 161c and the electrode connecting portion 213. To this end, the sealing portion 212 should be positioned closer to the hole 210'' than the electrode connecting portion 213.

[0164] The sealing portion 212 is formed in a ring shape, and there is no particular limitation on the material of the sealing portion 212. The sealing portion 212 may be formed of a known sealing material.

[0165] The electrode connection portion 213 is connected to the assembly electrode formed on the substrate and supplies power to the assembly electrode. Figure 7 The power supplied by the power supply unit 171 described in the accompanying drawings is applied to the assembly electrode 161 c to form an electric field on the substrate.

[0166] On the other hand, the side wall portion 210" is formed at the edge of the bottom portion 210'. The side wall portion 210" prevents the fluid from penetrating to the opposite side of the assembly surface of the substrate during self-assembly. Specifically, the self-assembly device of the present invention performs self-assembly in a state where the substrate is immersed in the fluid. The side wall portion 210" prevents the fluid from penetrating to the opposite side of the assembly surface of the substrate when the substrate is immersed in the fluid.

[0167] To this end, the sidewall portion 210" is formed to surround the entire edge of the substrate. The height of the sidewall portion 210" should be formed to be greater than the depth of the substrate immersed in the fluid. The sidewall portion 210" prevents the fluid from penetrating to the side opposite to the assembly surface of the substrate, thereby preventing damage to the substrate, and allows the buoyancy of the fluid to act only on one side of the substrate. This will be explained later.

[0168] Meanwhile, the second frame 220 serves to press the substrate against the opposite side of the first frame 210 during self-assembly. Like the first frame 210, the second frame 220 has a hole extending through its center. The size of the hole formed in the second frame 220 is equal to or greater than the size of the hole 210'' formed in the first frame 210.

[0169] The hole formed in the second frame 220 exposes the surface opposite the assembly surface of the substrate to the outside. The surface opposite the assembly surface of the substrate should be exposed to the outside with an area equal to or larger than the assembly surface. This is because the magnetic field forming unit 300 forms a magnetic field on the side opposite the assembly surface of the substrate. The surface opposite the assembly surface of the substrate should be exposed to the outside so that the magnetic field forming unit 300 can be sufficiently close to the substrate.

[0170] On the other hand, in the second state, the substrate S is loaded between the first frame 210 and the second frame 220. Thus, the substrate S is loaded while sliding on one side of the second frame 220. At least one of the first frame and the second frame may be formed with a protrusion for guiding the alignment position of the substrate so that the substrate is aligned in an accurate position. In one embodiment, referring to Figure 13 The first frame 210 may be formed with a protrusion 211 for guiding the alignment position of the substrate S.

[0171] On the other hand, if the substrate S is loaded onto the second frame 220, at least one of the first frame 210 and the second frame 220 moves vertically, thereby pressing the substrate. To this end, the substrate chuck 200 may include a frame moving portion disposed on at least one of the fixing portion 230, the first frame 210, and the second frame 220. At this time, the sealing portion 212 presses the substrate S.

[0172] In one embodiment, the fixing portion 230 may be provided with a frame moving portion that moves the second frame 220 vertically. If the substrate S is loaded onto the second frame 220 in the second state of the substrate chuck, the vertical moving portion moves the second frame 220 upward, thereby firmly fixing the substrate S between the first frame 210 and the second frame 220. At this time, the electrode connecting portion 213 provided on the first frame 210 is connected to the assembly electrode of the substrate S, and the sealing portion 212 provided on the first frame 210 presses the edge of the substrate S. When the substrate chuck is switched to the first state in this state, it is concluded that Figure 14 That shape.

[0173] However, this is not limiting. The frame moving portion may be configured to horizontally move one of the first frame 210 and the second frame 220 relative to the other. In this case, the frame moving portion is configured to vertically and horizontally move one of the first frame 210 and the second frame 220 relative to the other. Horizontally moving one of the first frame 210 and the second frame 220 relative to the other can change the connection point between the electrode connecting portion 213 and the assembled electrode. This can be used to detect defects in the assembled electrode.

[0174] On the other hand, a rotating portion 240 is provided on one side of the fixing portion 230 of the substrate chuck 200. The rotating portion 240 rotates the fixing portion 230 to switch the upper and lower relationship between the first frame 210 and the second frame 220. By the rotation of the rotating portion 240, the substrate chuck 200 switches from one state of the first state to the other state. Figure 7 The control unit 172 described above controls the rotation speed, rotation degree, rotation direction, etc. of the rotating unit 240.

[0175] In one embodiment, the substrate chuck 200 is in the second state before the substrate S is loaded. The control unit 172 controls the rotating unit 240 to rotate the fixing unit 230 180 degrees after the substrate S is loaded, so that the substrate chuck 200 switches to the first state.

[0176] On the other hand, a vertical moving portion and a horizontal moving portion are disposed on one side of the fixed portion 230 .

[0177] The horizontal moving part moves at least one of the fixing part 230 , the first frame 210 , and the second frame 220 so that the assembly surface of the substrate can be aligned with the open position of the assembly chamber after the substrate is loaded.

[0178] The vertical moving portion moves at least one of the fixing portion 230, the first frame 210, and the second frame 220 to adjust the vertical distance between the substrate and the assembly chamber. The vertical moving portion can correct the curvature of the substrate S. This will be described later.

[0179] In summary, the substrate S is in the second state of the substrate chuck 200 (refer to Figure 12 ) is loaded. Then, the substrate chuck 200 is switched to the first state (refer to Figure 11 ) after which the assembly chamber is aligned. During this process, the substrate chuck 200 moves vertically and horizontally so that the assembly surface of the substrate S contacts the fluid filled in the assembly chamber. Then, the control unit 172 controls the magnetic field forming unit 300.

[0180] Next, the magnetic field forming unit 300 will be described.

[0181] Figure 15 is a three-dimensional diagram of a magnetic field forming portion according to an embodiment of the present invention. Figure 16 is a side view of a magnetic field forming portion according to an embodiment of the present invention, Figure 17 1 is a bottom side view of a magnetic field forming portion according to an embodiment of the present invention, Figure 18 This is a conceptual diagram showing the loci of a plurality of magnets provided in the magnetic field forming portion of the present invention.

[0182] Referring to the drawings, the magnetic field forming unit 300 includes a magnet array 310, a vertical moving unit, a horizontal moving unit, and a rotating unit 320. The magnetic field forming unit 300 is disposed on the upper side of the assembly electrode and plays a role in forming a magnetic field.

[0183] Specifically, the magnet array 310 includes a plurality of magnets 313. The magnets 313 provided in the magnet array 310 can be permanent magnets or electromagnets. The plurality of magnets 313 form a magnetic field to guide the plurality of semiconductor light-emitting devices to the assembly surface of the substrate.

[0184] The magnet array 310 may include a support portion 311 and a magnet moving portion 312 . The support portion 311 is connected to the vertical moving portion and the horizontal moving portion 320 .

[0185] On the other hand, one end of the magnet moving part 312 is fixed to the support part 311, and the magnet 313 is fixed to the other end of the magnet moving part 312. The magnet moving part 312 is formed to be extendable in length, and as the magnet moving part 312 is extended or contracted, the distance between the magnet 313 and the support part 311 changes.

[0186] As shown in the figure, the magnet moving unit 312 can be configured to vertically move a plurality of magnets 313 arranged in a row at once. In this case, the magnet moving unit 312 can be arranged in rows of the magnet array.

[0187] Alternatively, the magnet moving parts 312 may be configured to have the same number as the number of magnets provided in the magnet array, thereby enabling the distance between each of the plurality of magnets and the support portion to be adjusted differently.

[0188] The plurality of magnet moving parts serve to finely adjust the spacing between the magnets 313 and the substrate S. If the substrate is curved, the plurality of magnet moving parts serve to uniformly adjust the spacing between the magnets 313 and the substrate S. Self-assembly can be performed with the magnets 313 in contact with the substrate S or with a predetermined distance between the magnets 313 and the substrate S.

[0189] On the other hand, the horizontal moving part may include a rotating part. When performing self-assembly, the horizontal moving part provided in the magnetic field forming part 300 rotates the magnet while moving the magnet in one direction. Thus, the magnet array 310 moves in one direction while rotating relative to a predetermined rotation axis. For example, referring to Figure 18 , the magnets 313 provided in the magnet array 310 can move while drawing a trajectory P that is a mixture of curves and straight lines.

[0190] The semiconductor light emitting device may be supplied in a state where the magnetic field forming part 300 is close to the substrate S within a predetermined distance.

[0191] Figure 19 is a conceptual diagram showing a situation in which semiconductor light emitting devices are supplied.

[0192] Reference Figure 19 The assembly chamber 500, described later, may be equipped with a chip supply unit 400. The chip supply unit 400 supplies semiconductor light-emitting devices to the assembly surface of the substrate S after the substrate S is aligned with the assembly chamber 500. Specifically, the chip supply unit 400 may include a chip receiving portion capable of receiving a chip at its upper portion, a vertical movable portion, and a horizontal movable portion. The vertical movable portion and the horizontal movable portion enable the chip receiving portion to move within the fluid filled within the assembly chamber.

[0193] The chip accommodating portion can be loaded with a plurality of semiconductor light-emitting devices. After the substrate is aligned with the assembly chamber, when the magnetic field generating portion 300 and the substrate are brought within a predetermined distance, a magnetic field with a predetermined strength or greater is generated on the assembly surface. In this state, if the chip accommodating portion and the assembly surface are brought within a predetermined distance, the plurality of semiconductor light-emitting devices loaded in the chip accommodating portion come into contact with the substrate. A vertical movement portion provided in the chip supply portion vertically moves the chip accommodating portion and a portion of the substrate assembly surface within a predetermined distance.

[0194] After a specified time has passed, the vertical moving portion provided in the chip supply portion moves vertically so that the chip accommodating portion and a portion of the assembly surface of the substrate are separated by a specified distance. Then, the horizontal moving portion provided in the chip supply portion moves the chip accommodating portion horizontally so that the chip accommodating portion overlaps with an area different from the portion of the assembly surface. Then, the vertical moving portion provided in the chip supply portion moves vertically so that the chip accommodating portion and the different area are brought closer to within a specified distance. By repeating this process, the chip supply portion brings a plurality of semiconductor light-emitting devices into contact with the entire area of ​​the assembly surface of the substrate. Self-assembly can be performed in a state where a plurality of semiconductor light-emitting devices are evenly dispersed and in contact with the entire assembly surface area of ​​the substrate.

[0195] As previously mentioned, two major issues arise during self-assembly. The second issue is that the semiconductor light-emitting devices cannot be completely evenly dispersed in the fluid, and the magnetic field formed on the assembly substrate surface is not completely uniform, resulting in the semiconductor light-emitting devices being concentrated in only a portion of the assembly substrate. Using the aforementioned chip supply unit 400 can resolve this second issue.

[0196] However, this is not limiting, and the chip supply unit is not an essential component of the present invention. Self-assembly can be performed with the semiconductor light-emitting devices dispersed in a fluid, or with a plurality of semiconductor light-emitting devices dispersed and brought into contact with the assembly surface of the substrate by a unit other than the chip supply unit.

[0197] Next, the assembly chamber 500 will be described.

[0198] Figure 20 is a top view of an assembly chamber according to an embodiment of the present invention. Figure 21 It is along Figure 20 The cross-sectional view taken along line A-A' is Figure 22 is a three-dimensional diagram of an assembly chamber according to an embodiment of the present invention. Figure 23 and Figure 24 is a conceptual diagram showing an assembly chamber having a buffer area.

[0199] Assembly chamber 500 has a space for accommodating a plurality of semiconductor light-emitting devices. This space can be filled with a fluid, such as water, serving as an assembly solution. Thus, assembly chamber 500 can be a water tank and can be open. However, the present invention is not limited thereto; assembly chamber 500 can also be a closed space.

[0200] In the assembly chamber 500 , the substrate S is arranged with its assembly surface facing downward for assembling the plurality of semiconductor light emitting devices 150 . For example, the substrate S is moved to an assembly position by a substrate chuck 200 .

[0201] At this time, in the assembly position, the assembly surface of the substrate S faces the bottom of the assembly chamber 500 . Therefore, the assembly surface faces the direction of gravity and is configured to be immersed in the fluid in the assembly chamber 500 .

[0202] In one embodiment, referring to Figures 20 to 22 The assembly chamber 500 can be divided into two areas. Specifically, the assembly chamber 500 can be divided into an assembly area 510 and an inspection area 520. In the assembly area 510, the semiconductor light emitting device configured in the fluid is assembled to the substrate S while the substrate S is immersed in the fluid.

[0203] However, the present invention is not limited thereto. The assembly chamber 500 may be divided into a plurality of areas. Specifically, the assembly chamber 500 may be divided into a plurality of assembly areas and an inspection area. In this case, different types of semiconductor light-emitting devices may be assembled in each assembly area. For example, the assembly chamber 500 may include three assembly areas. In each assembly area, blue, red, and green semiconductor light-emitting devices may be assembled sequentially.

[0204] In this specification, for the sake of convenience, the structure of an assembly chamber having one assembly area and one inspection area is described, but the present invention is not limited thereto. The assembly chamber may have a plurality of assembly areas and a plurality of inspection areas.

[0205] In the inspection area 520 , the self-assembled substrate S is inspected. Specifically, after the substrate S is assembled in the assembly area, it is transferred to the inspection area by a substrate chuck.

[0206] On the other hand, when there are a plurality of assembly areas, when self-assembly is completed in a certain assembly area, the substrate chuck moves the substrate to another assembly area.

[0207] When a substrate is transferred to another area within the assembly chamber, it is preferably transferred while immersed in a fluid. Specifically, the assembly area 510 and the inspection area 520 can be filled entirely with the same fluid. When the substrate S disposed in the assembly area 510 is removed from the fluid, the assembled semiconductor light-emitting device may become detached from the substrate due to the surface energy between the fluid and the semiconductor light-emitting device. Therefore, the substrate is preferably transferred while immersed in the fluid.

[0208] On the other hand, when removing the boundaries between areas within the assembly chamber to allow the substrate to be moved to different areas while immersed in the fluid, there is a risk that semiconductor light-emitting devices floating in the fluid could move to unintended areas. For example, a red semiconductor light-emitting device could float in an assembly area for assembling red semiconductor light-emitting devices among multiple assembly areas. In this state, without boundaries between assembly areas, the red semiconductor light-emitting device can freely move to another assembly area. This could result in incorrect assembly.

[0209] As described above, the areas set in the assembly chamber should be isolated from each other, and when the substrates are moved to different areas, the substrates need to remain immersed in the fluid. Figure 23 and Figure 24 As shown, a structure is used in which buffer areas (B, B1, and B2) are provided between different areas. However, the buffer areas (B, B1, and B2) cause the size of the assembly chamber to become unnecessarily large. In addition, the buffer areas (B, B1, and B2) need to be provided between all areas, so the number of buffer areas also increases as the number of areas provided in the assembly chamber increases.

[0210] The present invention provides an assembly chamber in which regions provided in the assembly chamber are isolated from each other while minimizing the size of the assembly chamber and in which a substrate can be moved between the regions while being immersed in a fluid.

[0211] The structure of the assembly chamber will be described in detail below.

[0212] Figure 25 is a conceptual diagram showing an assembly chamber including a gate portion, Figure 26 This is an enlarged view of the gate portion provided in the assembly chamber of the present invention. Figure 27 This is a conceptual diagram emphasizing the bottom and sidewall of the assembly chamber of the present invention. Figure 28 This is a conceptual diagram emphasizing the gate portion of the present invention.

[0213] Referring to the drawings, the assembly chamber of the present invention includes a bottom 501 , a sidewall 502 , and a partition wall 530 .

[0214] The bottom portion 501 is formed in a plate shape, and a plurality of components constituting the assembly chamber may be arranged in a partial region of the bottom portion 501 .

[0215] In one embodiment, a light-transmitting portion 503 may be provided on a portion of the bottom 501. Specifically, the bottom 501 may be formed of an opaque material. A portion of the bottom 501 may be configured to allow light to pass through, allowing the interior of the assembly chamber to be observed from outside. To this end, a hole may be formed through the bottom 501. The light-transmitting portion 503 is secured to the edge of the hole.

[0216] The assembly chamber is filled with fluid, so if there is a gap between the bottom 501 and the light-transmitting portion 503, the fluid can flow out through the gap. Therefore, a complete seal must be achieved between the bottom 501 and the light-transmitting portion 503. To this end, a sealing portion can be provided between the bottom 501 and the light-transmitting portion 503.

[0217] The light-transmitting sections 503 can be arranged in accordance with the respective areas provided in the assembly chamber. That is, the light-transmitting sections 503 can be provided in the same number as the number of areas provided in the assembly chamber. The light-transmitting sections 503 can be used to observe the self-assembly status from outside the assembly chamber.

[0218] On the other hand, for the arrangement of components, a plurality of holes may be formed in the bottom 501. A seal should be maintained between the arranged plurality of components and the bottom 501 to prevent fluid from flowing out through the plurality of holes.

[0219] On the other hand, a side wall portion 502 is formed on the bottom 501. The side wall portion 502 is formed on the bottom 501 at a specified height and is arranged at the edge of the bottom 501. The space surrounded by the bottom 501 and the side wall portion 502 is filled with a fluid. The fluid should not flow out from between the bottom 501 and the side wall portion 502. To this end, the bottom 501 and the side wall portion 502 can be made into an integral body or can be completely combined by welding or the like. However, this is not limited to this, and the combination between the bottom 501 and the side wall portion 502 can be any combination as long as it prevents the fluid from flowing out from between the bottom 501 and the side wall portion 502.

[0220] On the other hand, for the arrangement of components, a plurality of holes may be formed in the side wall portion 502. A seal should be maintained between the arranged plurality of components and the side wall portion 502 to prevent fluid from flowing out through the holes.

[0221] Not only the fluid but also other components are arranged in the space surrounded by the bottom portion 501 and the side wall portion 502. Specifically, the partition wall portion 530 is arranged in the space surrounded by the bottom portion 501 and the side wall portion 502.

[0222] The partition wall portion 530 is formed on the bottom portion 501 and is formed to extend from one inner side surface among a plurality of inner side surfaces of the side wall portion 502 to another inner side surface opposite to the one inner side surface.

[0223] The plurality of areas provided in the assembly chamber are divided by the partition wall 530. In one embodiment, the assembly chamber includes four areas, and when the four areas are arranged in a pattern, a total of three partition walls are provided in the assembly chamber. However, this is not limiting, and the shape of the partition wall 530 may vary depending on the arrangement of the plurality of areas.

[0224] On the other hand, when the partition wall portion 530 is formed to have the same height as the side wall portion 502 , although a plurality of regions can be completely isolated, in order to transfer the substrate to different regions, it is necessary to separate the substrate from the fluid at least once.

[0225] On the other hand, when at least a portion of the partition wall portion 530 is formed to be lower than the height of the side wall portion 502 (more precisely, lower than the water level of the fluid), although the substrate does not need to be separated from the fluid when it is moved to different areas, the fluids filled in different areas are mixed, and therefore the semiconductor light-emitting device floating in the fluid penetrates into an undesirable area.

[0226] In order to solve the above two problems, at least a portion of the partition wall 530 is formed to have a variable vertical height relative to the bottom 501. To this end, the partition wall 530 includes a frame portion 531 and a gate portion 532.

[0227] The frame portion 531 is fixed to the bottom portion 501. Specifically, the frame portion 531 is fixed to the bottom portion 501 to prevent fluid from passing between the bottom portion 501 and the frame portion 531. The fixing member of the frame portion 531 is not particularly limited.

[0228] On the other hand, a portion of the frame portion 531 is fixed to the inner side surface of the side wall portion 502 and another inner side surface of the side wall portion 502 opposite to the inner side surface. The portion of the frame portion 531 is fixed to the inner side surface of the side wall portion 502 to prevent fluid from passing between the side wall portion 502 and the frame portion 531. The fixing member of the frame portion 531 is not particularly limited.

[0229] On the other hand, a portion of the frame portion 531 is formed to be lower than the height of the sidewall portion 502 relative to the bottom portion 501. Specifically, the frame portion 531 may have a recessed portion formed toward the bottom portion 501. The recessed portion is formed in the center of the frame portion 531, and the height of the frame portion 531 at the location where the recessed portion is formed is lower than the sidewall portion 502. On the other hand, the height of the frame portion 531 at the location where the recessed portion is not formed may be equal to the sidewall portion 502.

[0230] The substrate passes through the recessed portion when moving between regions, and thus the recessed portion is formed to have a depth sufficient to allow the substrate to move between regions while being immersed in a fluid.

[0231] The gate portion 532 is configured to be movable along one side of the frame portion 531. Specifically, the gate portion 532 is configured to be movable vertically relative to the bottom portion 501. As the gate portion 532 moves vertically, the area of ​​overlap between the gate portion 532 and the recessed portion changes. Within the driving range of the gate portion 532, when the gate portion 532 reaches the position farthest from the bottom portion 501 (hereinafter referred to as the first height), the gate portion 532 can completely overlap the recessed portion. At this point, the gate portion 532 is in close contact with one side of the frame portion 531.

[0232] To ensure close contact between the gate portion 532 and the frame portion 531, a sealing portion 533 may be provided on the surface of the gate portion 532 that contacts the frame portion 531. When the gate portion 532 is in close contact with the frame portion 531, fluid cannot pass between the gate portion 532 and the frame portion 531. The gate portion 532 increases the height of the partition wall portion 530.

[0233] In contrast, when the gate portion 532 descends from the first height to the position closest to the bottom portion 501 within the gate portion 532's operating range (the second height), the gate portion 532 does not overlap with the recessed portion, or may overlap with the recessed portion by a minimal area. In this state, the gate portion 532 does not need to be in close contact with the frame portion 531. The height of the partition wall portion 530 is reduced by the gate portion 532.

[0234] The gate portion 532 moves vertically from one of the first and second heights to the other. In one embodiment, the gate portion 532 can move vertically while being spaced a predetermined distance from the frame portion 531. To this end, the gate portion 532 includes not only a vertically movable member capable of vertically moving relative to the base 501, but also a horizontally movable member capable of moving in a direction parallel to the base 501.

[0235] For example, when the position of the gate portion 532 changes from the second height to the first height, the gate portion 532 is spaced a predetermined distance from the frame portion 531 at the second height. In this state, the gate portion 532 moves vertically to the first height. Then, the gate portion 532 moves horizontally relative to the bottom portion 501 until it is in close contact with the frame portion 531.

[0236] For example, when the position of the gate portion 532 changes from a first height to a second height, the gate portion 532 is in close contact with the frame portion 531 at the first height. In this state, the gate portion 532 moves horizontally relative to the bottom portion 501 to a predetermined distance from the frame portion 531. The gate portion 532 then moves vertically to the second height.

[0237] In this manner, the present invention can prevent damage to the sealing portion 533 provided on the gate portion 532 during repeated vertical movement of the gate portion 532. However, the present invention is not limited thereto, and the gate portion 532 may perform vertical movement while being in close contact with the frame portion 531. In this case, the gate portion 532 may not include a horizontal moving member.

[0238] Figure 29 and Figure 30 It is a conceptual diagram showing the change in height of the partition wall portion.

[0239] like Figure 29 As shown, during self-assembly, the gate portion 532 remains in close contact with the frame portion 531 at a first height. Thus, because the height of the partition wall 530 is the same as that of the sidewall 502, fluid filled in the assembly area cannot flow into the inspection area. This prevents the semiconductor light-emitting device from leaking into the inspection area during self-assembly.

[0240] On the other hand, Figure 30 As shown, when the substrate S is transferred, the gate portion 532 descends from the first height, removing the boundary between the assembly area 510 and the inspection area 520. Thus, the substrate chuck can transfer the substrate from the assembly area to the inspection area by only horizontal movement without separate vertical movement.

[0241] As described above, the present invention changes the height of the partition wall 530 by vertically moving the shutter 532. Thus, the present invention can completely separate different areas provided in the assembly chamber or enable substrates to move between different areas while being immersed in a fluid.

[0242] On the other hand, various components can be arranged in the assembly chamber of the present invention.

[0243] Figures 31 to 33 This is a conceptual diagram emphasizing a plurality of components provided in the assembly chamber of the present invention.

[0244] Reference Figure 31 The assembly chamber may be provided with a water level sensor 540, which can sense the water level of the fluid filled in the assembly chamber. In one embodiment, the assembly chamber may be provided with an ultrasonic sensor capable of sensing the water level of the fluid.

[0245] The water level sensor 540 can be used to maintain a constant level of fluid by adding fluid when fluid is lost during the process. In addition, the water level of the fluid can be maintained constant by removing fluid when the fluid is overfilled.

[0246] For this purpose, refer to Figure 32 The assembly chamber of the present invention may include a fluid supply portion 550a for supplying fluid and a fluid discharge portion 550b for discharging fluid. In one embodiment, the fluid supply portion 550a may be disposed on the sidewall portion 502, and the fluid discharge portion 550b may be disposed on the bottom portion 501. Alternatively, the fluid supply portion 550a and the fluid discharge portion 550b may be disposed in a plurality of regions provided in the assembly chamber.

[0247] On the other hand, refer to Figure 33 The assembly chamber may be provided with an ultrasonicator 550 for preventing the semiconductor light emitting devices from agglomerating. The ultrasonicator 550 may prevent the semiconductor light emitting devices from agglomerating by vibration.

[0248] As described above, according to the present invention, since the height of the partition wall portion used to divide the multiple areas set in the assembly chamber can be adjusted, the multiple semiconductor light-emitting devices floating in each area can be prevented from mixing with each other, and the substrate can move freely in each area while immersed in the fluid.

Claims

1. An assembly chamber formed to contain a fluid, characterized in that The assembly chamber comprises: bottom; a side wall portion configured to be formed on the bottom portion at a predetermined height and to surround the bottom portion; and The partition wall portion is formed on the bottom portion and is formed to extend from one inner side surface among the plurality of inner side surfaces of the side wall portion to another inner side surface opposite to the one inner side surface. At least a portion of the partition wall portion is formed so that a vertical height relative to the bottom portion can be changed; The partition wall portion includes: a frame portion fixed to the bottom; and a gate portion formed to be movable along one side of the frame portion; The height of at least a portion of the partition wall portion changes as the shutter portion moves.

2. The assembly chamber according to claim 1, characterized in that The gate portion switches to another state from one of a first state where the gate portion is located at a first height relative to the bottom portion and a second state where the gate portion is located at a second height lower than the first height.

3. The assembly chamber according to claim 2, characterized in that: The shutter portion is in close contact with the frame portion in the first state.

4. The assembly chamber according to claim 3, characterized in that: The shutter portion is in a state of being in close contact with the frame portion, is first spaced apart from the frame portion by a predetermined distance, and then switches to a second state.

5. The assembly chamber according to claim 3, characterized in that: The invention further includes a sealing portion, which is arranged on a surface of the gate portion that is in close contact with the frame portion.

6. The assembly chamber according to claim 1, wherein: A water level sensor is further included, and the water level sensor is configured to sense a water level of the contained fluid.

7. The assembly chamber according to claim 6, characterized in that: Also includes: a fluid supply portion, disposed on at least one of the bottom portion and the sidewall portion, and supplying fluid to the assembly chamber; as well as The fluid discharge portion is disposed on at least one of the bottom portion and the side wall portion, and discharges the contained fluid to the outside.

8. The assembly chamber according to claim 1, wherein: The device further includes an ultrasonic instrument disposed on at least one of the bottom portion and the side wall portion and configured to vibrate the contained fluid at a predetermined frequency.

9. The assembly chamber according to claim 1, wherein: At least a portion of the bottom portion is formed of a light-transmitting layer.

10. The assembly chamber according to claim 1, wherein: The frame portion has a recessed portion formed toward the bottom portion.

11. The assembly chamber according to claim 10, characterized in that: The recessed portion is formed in a central portion of the frame portion.

12. The assembly chamber according to claim 11, characterized in that The height of the frame portion at a position where the recessed portion is provided is lower than the height of the side wall portion.

13. The assembly chamber according to claim 1, wherein: The gate portion includes: a vertical moving portion configured to move vertically relative to the base; and The horizontal moving portion is configured to move horizontally relative to the bottom portion.

14. The assembly chamber according to claim 13, characterized in that The gate portion contacts the frame portion by horizontally moving relative to the bottom portion.

15. The assembly chamber according to claim 1, wherein: The assembly chamber is divided into at least one assembly area and at least one inspection area, In the at least one assembly area, a plurality of light emitting diodes are assembled on a substrate, and in the at least one inspection area, the plurality of light emitting diodes assembled on the substrate are inspected.

16. The assembly chamber according to claim 15, characterized in that The assembly chamber includes a plurality of assembly areas, each assembly area corresponding to a light emitting diode of a certain color.

17. An assembly chamber containing a fluid for self-assembling a plurality of light emitting diodes onto a substrate, characterized in that: The assembly chamber comprises: at least one assembly area containing the fluid and defined by a bottom portion and a sidewall portion; and a partition wall portion located in the center of the assembly chamber and having a height variable from the bottom, the height being variable between a height of the side wall portion and a height smaller than the side wall portion; The partition wall portion includes: a frame portion fixed to at least one of the bottom portion and the side wall portion; and The gate portion is movable in a vertical direction along one surface of the frame portion.

18. The assembly chamber according to claim 17, characterized in that The assembly chamber includes at least one assembly area and at least one inspection area divided by the partition wall portion.

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