Interposer substrate, method for manufacturing interposer substrate, and method for transferring light-emitting elements

Abstract

This interposer substrate comprises: a transparent substrate; an ablation layer provided on the transparent substrate; a catch layer provided on the ablation layer and for mounting light-emitting elements; and a light-blocking component for preventing laser light radiated to the catch layer from passing through the ablation layer.

Description

Relay substrate, method for manufacturing a relay substrate, and method for transferring a light-emitting element

[0001] The present disclosure relates to a relay substrate for transferring a light-emitting element, a method for manufacturing a relay substrate, and a method for transferring a light-emitting element.

[0002] Self-emissive displays, in which each pixel is equipped with a light-emitting element to emit light on its own, do not require components such as backlight units and liquid crystal layers, and color filters can also be omitted; therefore, they are structurally simple and can offer a high degree of design freedom.

[0003] Among self-emissive displays, micro LED displays are composed of multiple micro LEDs with a size in the micro range. Compared to LCDs that require a backlight, micro LED displays can provide excellent contrast, excellent response time, and excellent energy efficiency.

[0004] Micro LEDs can be formed on an epi substrate through an epi process, etc., and then transferred to a target substrate through a relay substrate to form a display module.

[0005] Methods for transferring a micro LED formed on an epitaxial substrate to a target substrate through a relay substrate include transfer using a stamp and transfer using a laser.

[0006] The method of transferring using laser light can lower the defect rate of micro LEDs and has a relatively high transfer yield, so development is underway for this.

[0007] The present disclosure may provide a relay substrate capable of absorbing laser light, a method for manufacturing a relay substrate, and a method for transferring a light-emitting element using a relay substrate capable of absorbing laser light.

[0008] The technical problems to be solved in this document are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this invention belongs from the description below.

[0009] A relay substrate according to one embodiment of the present disclosure may include: a transparent substrate; an ablation layer provided on the transparent substrate; a catch layer provided on the ablation layer for mounting a light-emitting element; and a light blocking portion for preventing laser light irradiated onto the catch layer from being transmitted to the ablation layer.

[0010] The light blocking member may be a light blocking agent included in the catch layer.

[0011] The light blocking agent may absorb laser light of a predetermined wavelength irradiated onto the catch layer.

[0012] The content of the light blocking agent in the above catch layer may be greater than a predetermined content.

[0013] The light blocking member may include a light blocking layer provided between the ablation layer and the catch layer.

[0014] The light blocking member may include a light blocking layer provided on the catch layer.

[0015] A method for manufacturing a relay substrate according to one embodiment of the present disclosure may include: a step of stacking an ablation layer on a transparent substrate; a step of stacking a catch layer for mounting a light-emitting element on the ablation layer; and a step of forming a light blocking portion to prevent laser light irradiated onto the catch layer from being transmitted to the ablation layer.

[0016] The step of forming the light blocking portion may include the step of adding a light blocking agent to the catch layer.

[0017] The step of adding the light blocking agent to the catch layer may include the step of adding a light blocking agent to the catch layer capable of absorbing laser light of a predetermined wavelength irradiated onto the catch layer.

[0018] The step of adding the light blocker to the catch layer may include adding the light blocker to the catch layer such that the content of the light blocker in the catch layer is greater than or equal to a predetermined content.

[0019] The step of forming the light blocking portion may include the step of stacking a light blocking layer on the ablation layer, and the step of stacking the catch layer may include the step of stacking the catch layer on the light blocking layer.

[0020] The step of forming the light blocking portion may include the step of laminating a light blocking layer on the catch layer.

[0021] A method for transferring a light-emitting element according to one embodiment of the present disclosure may include: providing a first intermediate substrate comprising a transparent substrate, an ablation layer provided on the transparent substrate, a catch layer provided on the ablation layer for mounting a light-emitting element, and a light blocking portion for preventing laser light irradiated onto the catch layer from being transmitted to the ablation layer; transferring a light-emitting element provided on an epitaxial substrate to the first intermediate substrate; transferring the light-emitting element transferred to the first intermediate substrate to a second intermediate substrate; and transferring the light-emitting element transferred to the second intermediate substrate to a target substrate.

[0022] The light blocking member may be a light blocking agent included in the catch layer.

[0023] The light blocking member may include a light blocking layer provided between the ablation layer and the catch layer.

[0024] According to the present disclosure, when laser light is irradiated onto a catch layer capable of supporting a light-emitting element, the laser light is prevented from being transmitted to an ablation layer that reacts to the laser light, thereby preventing transfer defects.

[0025] FIG. 1 is a drawing illustrating a relay substrate according to one embodiment.

[0026] FIG. 2 is a diagram illustrating the use of laser light to transfer a light-emitting element onto a relay substrate according to one embodiment, and is a diagram illustrating the state before the light-emitting element is transferred onto the relay substrate.

[0027] FIG. 3 is a block diagram schematically showing a laser transfer device according to one embodiment.

[0028] FIG. 4 is a block diagram schematically showing the laser oscillation unit of a laser transfer device according to one embodiment.

[0029] Figure 5 is a schematic diagram showing the mask illustrated in Figure 4.

[0030] Figure 6 is a diagram illustrating the occurrence of transfer defects as the ablation layer of the intermediate substrate reacts to laser light.

[0031] FIG. 7 is a drawing illustrating that no transfer defects occur due to the light blocking portion of a relay substrate according to one embodiment.

[0032] FIGS. 8 and 9 are drawings illustrating an example in which a light blocking member according to one embodiment is composed of a light blocking layer.

[0033] FIG. 10 is a flowchart for explaining a method for manufacturing a relay substrate according to one embodiment.

[0034] FIG. 11 is a diagram illustrating the etching process performed after a light-emitting element is transferred from an epitaxial substrate to a first intermediate substrate according to one embodiment.

[0035] FIG. 12 is a diagram illustrating the use of laser light to transfer a light-emitting element onto a second relay substrate, and is a diagram illustrating the state of the light-emitting element before it is transferred onto the second relay substrate.

[0036] FIG. 13 is a diagram showing the appearance of a light-emitting element transferred to a second relay substrate.

[0037] FIG. 14 is a diagram showing the etching process performed after the light-emitting element is transferred to the second intermediate substrate.

[0038] FIG. 15 is a diagram illustrating the use of laser light to transfer a light-emitting element onto a target substrate, and is a diagram illustrating the state before the light-emitting element is transferred onto the target substrate.

[0039] Figure 16 is a diagram illustrating the appearance of a light-emitting element transferred onto a target substrate.

[0040] Figure 17 is a diagram showing the etching process performed after a light-emitting element is transferred to a target substrate.

[0041] FIG. 18 is a flowchart for explaining a method of transferring a light-emitting element according to one embodiment.

[0042] The various embodiments of this document and the terms used therein are not intended to limit the technical features described in this document to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of said embodiments.

[0043] In relation to the description of the drawings, similar reference numerals may be used for similar or related components.

[0044] The singular form of the noun corresponding to the item may include one or multiple items, unless the relevant context clearly indicates otherwise.

[0045] In this document, each of the phrases such as "A or B", "at least one of A and B", "at least one of A or B", "A, B or C", "at least one of A, B and C", and "at least one of A, B, or C" may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof.

[0046] The term "and / or" includes a combination of multiple related described components or any of the multiple related described components.

[0047] The terms "part," "module," and "component" may be implemented in hardware or software. Depending on the embodiments, a plurality of "parts," "modules," and "components" may be implemented as a single component, or a single "part," "module," or "component" may include a plurality of components.

[0048] Terms such as "first," "second," or "first" or "second" may be used simply to distinguish a component from another component and do not limit the components in other aspects (e.g., importance or order).

[0049] Where any (e.g., 1st) component is referred to as "coupled" or "connected" to another (e.g., 2nd) component, with or without the terms "functionally" or "communicationly," it means that said any component may be connected to said other component directly (e.g., via a wire), wirelessly, or through a third component.

[0050] Terms such as "include" or "have" are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in this document, and do not preclude the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0051] When it is said that a component is "connected," "combined," "supported," or "in contact" with another component, this includes not only cases where the components are directly connected, combined, supported, or in contact, but also cases where they are indirectly connected, combined, supported, or in contact through a third component.

[0052] When it is said that a component is located "on" another component, this includes not only cases where one component is in contact with the other, but also cases where another component exists between the two components.

[0053] Meanwhile, terms such as "front," "rear," "left," "right," "top," and "bottom" used in the following description are defined based on the drawings; however, the shape and position of each component are not limited by these terms. For example, the front side may be defined as the +X side and the rear side as the -X side. For example, based on the drawings, the right side may be defined as the +Y side and the left side as the -Y side. For example, based on the drawings, the top side may be defined as the +Z side and the bottom side as the -Z side.

[0054] Transfer methods using laser light include laser lift-off (LLO) processing, laser blister processing, and laser ablation processing.

[0055] In the following description, the transfer method using laser light is described as a method using laser ablation, laser lift-off (LLO) treatment, or laser blister treatment.

[0056] Hereinafter, embodiments according to the present invention will be described in detail with reference to the attached drawings.

[0057] FIG. 1 is a drawing illustrating a relay substrate according to one embodiment.

[0058] Referring to FIG. 1, a relay substrate (1) according to one embodiment may include a transparent substrate (11), an ablation layer (12), and a catch layer (13). The relay substrate (1) is an intermediate medium for the transfer of a light-emitting element (100) and may be referred to as a carrier substrate or an infoteaser substrate.

[0059] The transparent substrate (11) may be composed of a material through which laser light can be transmitted. For example, the transparent substrate (11) may be a quartz substrate through which laser light can be transmitted. If the transparent substrate (11) is a quartz substrate, it can transmit a laser with a relatively wide wavelength range.

[0060] However, the transparent substrate (11) is not limited to a quartz substrate. For example, the transparent substrate (11) may be a quartz glass substrate, a glass substrate, or a polymer substrate.

[0061] The transparent substrate (11) can have various planar shapes. The transparent substrate (11) can be, for example, a rectangular or square shape, as well as a circular shape.

[0062] An ablation layer (12) according to one embodiment may be provided on a transparent substrate (11).

[0063] The ablation layer (12) can react to laser light. For example, the ablation layer (12) can be decomposed by laser light. The ablation layer (12) may be composed of at least one resin material selected from the group consisting of polyimide resin, acrylic resin, epoxy resin, polypropylene resin, polycarbonate resin, and ABS resin, which can react to laser light irradiated into it.

[0064] A catch layer (13) according to one embodiment may be provided on an ablation layer (12).

[0065] The catch layer (13) can accommodate a light-emitting element (100, see FIG. 2). For example, the catch layer (13) can accommodate a light-emitting element (100, see FIG. 2) provided on an epitaxial substrate (20) on the catch layer (13).

[0066] The catch layer (13) can function as an adhesive layer for fixing a light-emitting element (100, see FIG. 2) onto the catch layer (13).

[0067] For example, the catch layer (13) may be composed of an adhesive material for fixing a light-emitting element (100, see FIG. 2) onto the catch layer (13).

[0068] The adhesive material of the catch layer (13) may be composed of at least one resin material selected from the group consisting of urea resin, melamine resin, phenol resin, unsaturated polyester resin, epoxy resin, resorcinol resin, furan resin, vinyl acetate resin, polyvinyl alcohol resin, vinyl chloride resin, polyvinyl acetyl resin, acrylic resin, saturated polyester resin, polyamide resin and polyethylene resin.

[0069] Additionally, the adhesive material of the catch layer (13) may be composed of at least one rubber material selected from the group consisting of butadiene rubber, nitrile rubber, butyl rubber, silicone rubber, polychloroprene rubber, and ethylene rubber.

[0070] However, the adhesive material of the catch layer (13) in the present disclosure is not limited thereto and may be composed of various materials.

[0071] For example, the adhesive material of the catch layer (13) may be composed of at least one material selected from the group consisting of phenolic vinyl-based, phenolic chloroprene-based, phenolic nitrile-based, epoxy polyamide-based, and natrile rubber epoxy-based materials.

[0072] The catch layer (13) functions as an adhesive layer so that the light-emitting element (100, see FIG. 2) can be stably fixed on the intermediate substrate (1).

[0073] FIG. 2 is a diagram illustrating the use of laser light to transfer a light-emitting element onto a relay substrate according to one embodiment, and is a diagram illustrating the state before the light-emitting element is transferred onto the relay substrate.

[0074] Referring to FIG. 2, a light-emitting element (100) may be provided on an epi substrate (20). For example, a light-emitting element (100) may be provided on an epi substrate (20) through an epi process of depositing a light-emitting element (100) on a wafer (not shown).

[0075] The light-emitting element (100) may include a micro LED chip and an electrode.

[0076] The micro LED chip can be a flip LED chip, a lateral LED chip, or a vertical LED chip.

[0077] The electrode may include at least one metal selected from the group consisting of Au, Ag, Cu, Al, Pt, Ni, Cr, Ti, and ITO, or at least one of graphene.

[0078] The light-emitting element (100) can be provided according to the color required for the mounted display. For example, the light-emitting element (100) can be provided to emit at least one of red, green, and blue light.

[0079] In order to transfer the light-emitting element (100) provided on the epi substrate (20) to the relay substrate (1), laser light emitted from the laser transfer device (200) can be directed toward the upper side of the epi substrate (20).

[0080] Although not shown in FIG. 2, the epi substrate (20) may include a substrate (not shown) capable of transmitting laser light emitted from a laser transfer device (200) and a photosensitive layer (not shown) that reacts to laser light emitted from a laser transfer device (200). As a result, laser light irradiated toward the upper side of the epi substrate (20) passes through the substrate (not shown) capable of transmitting laser light and is irradiated onto the photosensitive layer (not shown), so that a light-emitting element (100) provided on the epi substrate (20) can be transferred to the relay substrate (1).

[0081] FIG. 3 is a block diagram schematically showing a laser transfer device according to one embodiment.

[0082] Referring to FIG. 3, the laser transfer device (200) may include a laser oscillator (201), a first stage (203) positioned at a certain distance below the laser oscillator (201) for moving one substrate (e.g., epitaxial substrate (20)) in the X, Y, and Z axis directions, a second stage (204) positioned at a certain distance below the first stage (203) for moving another substrate (e.g., relay substrate (1)) in the X, Y, and Z axis directions, and a control unit (207).

[0083] A laser oscillation unit (201) can irradiate laser light onto one substrate (e.g., epi-substrate (20)) to transfer a plurality of light-emitting elements (100) arranged on one substrate (e.g., epi-substrate (20)) to another substrate (e.g., relay substrate (1)).

[0084] The first stage (203) can load one substrate (e.g., epitaxial substrate (20)) and move to a predetermined position (e.g., a position to transfer a light-emitting element (100), a position to unload the substrate, etc.).

[0085] The second stage (204) can load another substrate (e.g., epi substrate (20)) and move to a predetermined position (e.g., a position to receive the light-emitting element (100), an unloading position of the other substrate, etc.).

[0086] The control unit (207) can control the operation of each component of the laser transfer device (200) to perform the transfer of the light-emitting element (100).

[0087] The control unit (207) may be implemented in the form of an Integrated Circuit (IC) or a System on a Chip (SoC). Additionally, the control unit (207) may be implemented in a form including a processor (208) and a memory (209). The processor (208) can execute instructions stored in the memory (209) to perform the manufacturing method of a display module according to various embodiments described in this disclosure. Various data and instructions may be stored in the memory (209).

[0088] FIG. 4 is a block diagram schematically showing the laser oscillation unit of a laser transfer device according to one embodiment.

[0089] Referring to FIG. 4, the laser oscillation unit (201) may include a laser generating unit (201a) for generating laser light, an attenuator (201b) for attenuating the intensity of the laser light output from the laser generating unit (201a), a homogenizer (201c) for forming the laser light that has passed through the attenuator (201b) to have a uniform distribution overall, and a P-lens (projection lens) (201e) for reducing the pattern of the laser light that has passed through the homogenizer (201c) and irradiating it onto a transfer area of ​​a substrate.

[0090] The laser generating unit (201a) can use various types of laser generators, such as excimer lasers, argon ion lasers, He-Ne lasers, YAG lasers, and carbon dioxide lasers, depending on the wavelength of the laser light.

[0091] The attenuator (201b) and the homogenizer (201c) are placed in the output path of the laser light to control the intensity of the laser light output from the laser generator (201a).

[0092] The homogenizer (201c) can homogenize the laser light as a whole when using an excimer laser, thereby making the quality of the laser light passing through the P-lens (201e) uniform. The homogenizer (201c) can enable homogenization by splitting solar radiation with significant variations in light intensity into small light sources and then overlapping them on the target surface.

[0093] The P-lens (201e) can focus the patterned laser light that has passed through the homogenizer (201c) and emit it in the same pattern toward the substrate loaded on the first stage (203). In this case, the pattern of the laser light irradiated onto the substrate can correspond to each position of the multiple light-emitting elements at the transfer location, for example, at the point where multiple light-emitting elements are arranged on the substrate.

[0094] The mask (201d) can be placed between the homogenizer (201c) and the P-lens (201e).

[0095] Figure 5 is a schematic diagram showing the mask illustrated in Figure 4.

[0096] Referring to FIG. 5, the mask (201d) may have a plurality of slits (201d1, 201d2) formed with a constant pitch (MP). The mask (201d) may have a constant pattern based on the pitch, spacing, size, etc. of the plurality of slits (201d1, 201d2). The mask (201d) may be replaced with another mask to correspond to a transfer pattern.

[0097] As patterned laser light passes through a plurality of slits (201d1, 201d2) of the mask (201d), it is emitted through a P-lens (201e) and irradiated onto a substrate, and the light-emitting elements arranged on the substrate can be transferred to another substrate placed at a constant interval below the substrate in a constant pattern or constant pitch.

[0098] Meanwhile, although the present disclosure describes a mask (201d) being disposed between the homogenizer (201c) and the P-lens (201e), it is not limited thereto, and the mask (201d) may be disposed outside the laser oscillator (201). For example, the mask (201d) may be disposed between the P-lens (201e) and the first stage (203).

[0099] Figure 6 is a diagram illustrating the occurrence of transfer defects as the ablation layer of the intermediate substrate reacts to laser light.

[0100] Referring to FIG. 6, laser light irradiated onto the epi substrate (20) can be irradiated onto the relay substrate (1). For example, laser light irradiated toward the upper side of the epi substrate (20) can pass through the epi substrate (20) and be irradiated onto the relay substrate (1).

[0101] In particular, when the area of ​​the laser light is larger than the area of ​​the light-emitting element (100), the laser light intensity is strong so that it passes through the light-emitting element (100) or scatters from the light-emitting element (100), or when the laser light is irradiated to a wafer missing area where the light-emitting element (100) was not formed during the process of forming the light-emitting element (100) in the epi process before forming the epi substrate (20), the laser light can be irradiated to the relay substrate (1).

[0102] When laser light is irradiated onto the intermediate substrate (1), a transfer defect may occur during transfer from the epi substrate (20) to the intermediate substrate (1). Below, a case in which a transfer defect occurs during transfer to the intermediate substrate (1) is described.

[0103] When laser light is irradiated onto the catch layer (13), the laser light is transmitted through the catch layer (13) and the ablation layer (12), and when the ablation layer (12) reacts to the laser light, the catch layer (13) can be expanded or the catch layer (13) can be pushed upward.

[0104] As a result, the catch layer (13) having a flat upper surface forms a curved shape due to the ablation layer (12), so that the light-emitting element (100) can be seated on the catch layer (13) in an inclined shape. In this case, transfer defects may occur continuously when transferring from the relay substrate (1) to another relay substrate or target substrate.

[0105] FIG. 7 is a drawing illustrating that no transfer defects occur due to the light blocking portion of a relay substrate according to one embodiment.

[0106] Referring to FIG. 7, a relay substrate (1) according to one embodiment may include a light blocking portion (14) to prevent laser light irradiated to a catch layer (13) from being transmitted to an ablation layer (12).

[0107] A light blocking portion (14) according to one embodiment may be a light blocking agent (14a) included in a catch layer (13). For example, the catch layer (13) may include a light blocking agent (14a) added to block laser light. Specifically, the catch layer (13) may include a light blocking agent (14a) added to an adhesive material for bonding a light-emitting element (100).

[0108] If a light blocker (14a) is included in the catch layer (13), laser light irradiated to the catch layer (13) can be absorbed by the light blocker (14a) and prevented from being transmitted to the ablation layer (12).

[0109] The laser transfer device (200) can emit laser light having a predetermined wavelength. For example, if the laser generating unit (201a, see FIG. 4) is an excimer laser, the laser light emitted from the laser transfer device (200) may have a wavelength of approximately 248 nm. In this case, laser light with a wavelength of approximately 248 nm may be irradiated onto the catch layer (13).

[0110] A light blocker (14a) according to one embodiment can absorb laser light of a predetermined wavelength irradiated onto a catch layer (13).

[0111] For example, the light blocker (14a) may be composed of a material that absorbs laser light of approximately 248 nm wavelength irradiated onto the catch layer (13).

[0112] However, the wavelength of laser light that can be absorbed by the light blocker (14a) according to the present disclosure is not limited thereto. For example, the light blocker (14a) may be composed of a material capable of absorbing laser light with a wavelength between approximately 10 nm and 400 nm.

[0113] The content of the light blocking agent (14a) according to one embodiment may be greater than a predetermined content.

[0114] The content of the light blocker (14a) refers to the proportion of the light blocker (14a) in the catch layer (13).

[0115] For example, if the catch layer (13) is composed of an adhesive material and a light blocker (14a), the content of the light blocker (14a) refers to the volume occupied by the light blocker (14a) out of the total volume of the adhesive material and the light blocker (14a).

[0116] The content of the light blocker (14a) may be 0.5% or more.

[0117] If the content of the light blocker (14a) is lower than a predetermined content, the laser light irradiated to the catch layer (13) cannot be absorbed, and the laser light can be transmitted to the ablation layer (12).

[0118] Therefore, the content of the light blocking agent (14a) needs to be greater than a predetermined content.

[0119] In addition, the content of the light blocker (14a) may be less than or equal to the critical content.

[0120] For example, the content of the light blocker (14a) may be 1% or less.

[0121] If the content of the light blocker (14a) is greater than the critical content, the adhesiveness of the catch layer (13) may be reduced, so the content of the light blocker (14a) needs to be less than or equal to the critical content.

[0122] However, the content of the light blocking agent (14a) is not limited to this and can be changed according to various embodiments.

[0123] According to the present disclosure, the laser light irradiated by the catch layer (13) is absorbed by the light blocker (14a) and prevented from being transmitted to the ablation layer (12), so that when transferring from the epitaxial substrate (20) to the intermediate substrate (1), the catch layer (13) can provide a flat surface, so that the light-emitting element (100) is properly seated and fixed on the catch layer (13), thereby preventing transfer defects.

[0124] FIGS. 8 and 9 are drawings illustrating an example in which a light blocking member according to one embodiment is composed of a light blocking layer.

[0125] Referring to FIGS. 8 and 9, the light blocking portion (14) may include a light blocking layer (14b) formed as a separate layer.

[0126] Referring to FIG. 8, a light blocking member (14) according to one embodiment may include a light blocking layer (14b) provided between an ablation layer (12) and a catch layer (13).

[0127] Additionally, referring to FIG. 9, a light blocking member (14) according to one embodiment may include a light blocking layer (14b) provided on a catch layer (13).

[0128] The light blocking layer (14b) may be a coating layer coated with a light blocking agent.

[0129] For example, referring to FIG. 8, the light blocking layer (14b) may be a coating layer coated with a light blocking agent on the ablation layer (12).

[0130] For another example, referring to FIG. 9, the light blocking layer (14b) may be a coating layer coated with a light blocking agent on the catch layer (13).

[0131] When a light blocker (14a, see FIG. 7) is added to the catch layer (13), the adhesiveness of the catch layer (13) may be reduced if the content of the light blocker (14a, see FIG. 7) is higher than the critical content. A separate light blocking layer (14b) according to the present disclosure may be composed of a relatively larger amount of light blocker than when the light blocker (14a, see FIG. 7) is added to the catch layer (13).

[0132] FIG. 10 is a flowchart for explaining a method for manufacturing a relay substrate according to one embodiment.

[0133] Referring to FIG. 10, a method for manufacturing a relay substrate according to one embodiment may include the step of stacking an ablation layer (12) on a transparent substrate (11) (1000).

[0134] The step of stacking the ablation layer (12) may include stacking it on a transparent substrate (11) using a material that can react to laser light irradiated into it.

[0135] Additionally, the step of stacking the ablation layer (12) may include stacking it on a transparent substrate (11) using a material that can be decomposed and removed by an etching process. The etching process may include a dry etching process using oxygen plasma.

[0136] A method for manufacturing a relay substrate (1) according to one embodiment may include the step of stacking a catch layer (13) on an ablation layer (12) (1100).

[0137] The step of stacking a catch layer (13) on an ablation layer (12) may include stacking the catch layer (13) on the ablation layer (12) using an adhesive material that can seat and fix a light-emitting element (100) on the catch layer (13).

[0138] Additionally, the step of stacking a catch layer (13) on an ablation layer (12) may include stacking on the ablation layer (12) using a material that can be decomposed and removed by an etching process.

[0139] A method for manufacturing a relay substrate (1) according to one embodiment may include the step of forming a light blocking portion (14) to prevent laser light irradiated to a catch layer (13) from being transmitted to an ablation layer (12) (1200).

[0140] The step of forming the light blocking portion (14) may include the step of adding a light blocking agent (14a) to the catch layer (13).

[0141] For example, the step of forming the light blocking portion (14) may include the step of adding a light blocking agent (14a) while the catch layer (13) is laminated on the ablation layer (12).

[0142] The step of adding a light blocker (14a) to a catch layer (13) according to one embodiment may include adding a light blocker (14a) to the catch layer (13) that can absorb laser light of a predetermined wavelength irradiated to the catch layer (13).

[0143] For example, the step of adding a light blocker (14a) to the catch layer (13) may include adding a light blocker (14a) composed of a material capable of absorbing laser light of a predetermined wavelength irradiated onto the catch layer (13).

[0144] The step of adding a light blocker (14a) to a catch layer (13) according to one embodiment may include adding a light blocker (14a) to the catch layer (13) such that the content of the light blocker (14a) in the catch layer (13) is greater than or equal to a predetermined content.

[0145] For example, the step of adding a light blocker (14a) to the catch layer (13) may include adding the light blocker (14a) such that the ratio of the volume of the light blocker (14a) to the total volume of the adhesive material of the catch layer (13) and the light blocker (14a) is at least a predetermined ratio (e.g., 0.5%).

[0146] The step of forming a light blocking portion (14) according to one embodiment may include the step of stacking a light blocking layer (14b) on an ablation layer (12). In this case, unlike FIG. 10, the step of stacking a catch layer (13) may be performed after the step of forming the light blocking portion (14) (1200). For example, if the step of forming the light blocking portion (14) is the step of stacking a light blocking layer (14b) on an ablation layer (12), the step of stacking the catch layer (13) may include the step of stacking the catch layer (13) on the light blocking layer (14b) after the light blocking layer (14b) is stacked on the ablation layer (12).

[0147] The step of forming a light blocking portion (14) according to one embodiment may include the step of stacking a light blocking layer (14b) on a catch layer (13).

[0148] The relay substrate (1) described above is described below as the first relay substrate (1). The first relay substrate (1) refers to a relay substrate that receives a light-emitting element (100) from an epitaxial substrate (20). Additionally, since the first relay substrate (1) described below is based on the premise that it includes a light-blocking portion (14), the description of the light-blocking portion (14) is omitted.

[0149] FIG. 11 is a diagram illustrating the etching process performed after a light-emitting element is transferred from an epitaxial substrate to a first intermediate substrate according to one embodiment.

[0150] Referring to FIG. 11, after the light-emitting element (100) is placed and fixed on the first intermediate substrate (1) and transferred from the epitaxial substrate (20) to the first intermediate substrate (1), an etching process can be performed.

[0151] When an etching process is performed, the ablation layer (12) and the catch layer (13) are composed of materials that can be decomposed and removed by the etching process, so the first intermediate substrate (1) can be in a state where the ablation layer (12) and the catch layer (13) portions, excluding the lower portion of the light-emitting element (100), are decomposed or removed.

[0152] FIG. 12 is a diagram illustrating the use of laser light to transfer a light-emitting element onto a second relay substrate, and is a diagram illustrating the state of the light-emitting element before it is transferred onto the second relay substrate.

[0153] FIG. 13 is a diagram showing the appearance of a light-emitting element transferred to a second relay substrate.

[0154] Referring to FIGS. 12 and 13, after performing an etching process with the light-emitting element (100) transferred to the first intermediate substrate (1), the direction of the laser light emitted from the laser transfer device (200) to transfer the light-emitting element (100) to the second intermediate substrate (50) is positioned so that it is directed toward the transparent substrate (11), and the second intermediate substrate (50) can be positioned on the lower side.

[0155] The second intermediate substrate (50) may include a transparent substrate (51), an ablation layer (52), and a catch layer (53) provided on the transparent substrate (51), similar to the transparent substrate (11), an ablation layer (12), and a catch layer (13) of the first intermediate substrate (1).

[0156] Hereinafter, for convenience of explanation, the transparent substrate (11), ablation layer (12), and catch layer (13) of the first intermediate substrate (1) are described as the first transparent substrate (11), the first ablation layer (12), and the first catch layer (13), respectively, and the transparent substrate (51), ablation layer (52), and catch layer (53) of the second intermediate substrate (50) are described as the second transparent substrate (51), the second ablation layer (52), and the second catch layer (53), respectively.

[0157] A laser beam emitted from a laser transfer device (200) passes through a first transparent substrate (11) and then passes through a first ablation layer (12). Due to the reaction of the first ablation layer (12) with the laser beam, the light-emitting element (100) is placed and fixed on the second catch layer (53) of the second intermediate substrate (50), so that the light-emitting element (100) can be transferred to the second intermediate substrate (50).

[0158] During the process of transferring the light-emitting element (100) to the second intermediate substrate (50), a first ablation layer (12) and a first catch layer (13) may remain as residues on the light-emitting element (100). In FIG. 14 below, a method for decomposing or removing the first ablation layer (12) and the first catch layer (13), which are residues on the light-emitting element (100), through an etching process is described.

[0159] FIG. 14 is a diagram showing the etching process performed after the light-emitting element is transferred to the second intermediate substrate.

[0160] Referring to FIG. 14, after the light-emitting element (100) is transferred to the second intermediate substrate (50), the first ablation layer (12) and the first catch layer (13), which are residues on the light-emitting element (100), can be decomposed or removed through an etching process. Additionally, through an etching process, the second intermediate substrate (50) can be in a state where the second ablation layer (52) and the second catch layer (53), excluding the portion corresponding to the lower portion of the light-emitting element (100), are decomposed or removed.

[0161] FIG. 15 is a diagram illustrating the use of laser light to transfer a light-emitting element onto a target substrate, and is a diagram illustrating the state before the light-emitting element is transferred onto the target substrate.

[0162] Figure 16 is a diagram illustrating the appearance of a light-emitting element transferred onto a target substrate.

[0163] Referring to FIG. 15, after performing an etching process with the light-emitting element (100) transferred to the second intermediate substrate (50), the laser light emitted from the laser transfer device (200) is positioned so that the direction of the laser light is directed toward the second transparent substrate (51) in order to transfer the light-emitting element (100) to the target substrate (60), and the target substrate (60) can be positioned on the lower side.

[0164] The target substrate (60) may include a driving circuit board (61) and an electrode layer (62).

[0165] The driving circuit board (61) may include a substrate having an array of thin film transistors (TFTs) for supplying driving current to a light-emitting element (100).

[0166] The electrode layer (62) is provided on a driving circuit board (61) and may be a layer having an anode electrode and a cathode electrode that can be electrically connected to the anode electrode for transmitting a driving current supplied from a thin film transistor (TFT) arrayed on the driving circuit board (61) to a light-emitting element (100).

[0167] Referring to FIG. 16, laser light emitted from a laser transfer device (200) passes through a second transparent substrate (51) and then passes through a second ablation layer (52). By the reaction of the second ablation layer (52) to the laser light, the light-emitting element (100) is placed on the electrode layer (62) of the target substrate (60), thereby allowing the light-emitting element (100) to be transferred to the target substrate (60).

[0168] During the process of transferring the light-emitting element (100) to the target substrate (60), a second ablation layer (52) and a second catch layer (53) may remain as residues on the light-emitting element (100). In FIG. 17 below, a method for decomposing or removing the second ablation layer (52) and the second catch layer (53), which are residues on the light-emitting element (100), through an etching process is described.

[0169] Figure 17 is a diagram showing the etching process performed after a light-emitting element is transferred to a target substrate.

[0170] Referring to FIG. 17, after the light-emitting element (100) is transferred to the target substrate (60), the second ablation layer (52) and the second catch layer (53), which are residues on the light-emitting element (100), can be decomposed or removed through an etching process.

[0171] Although not illustrated in FIG. 17, after disassembling or removing the second ablation layer (52) and the second catch layer (53) which are residues on the light-emitting element (100) through an etching process, a bonding process can be performed so that the light-emitting element (100) is fixed on the electrode layer (62). As a result, the light-emitting element (100) can electrically contact the anode electrode and the cathode electrode of the electrode layer (62) to receive a driving current.

[0172] The target substrate (60) on which the light-emitting element (100) is transferred can be directly used in a final product such as a display module.

[0173] FIG. 18 is a flowchart for explaining a method for transferring a light-emitting element according to one embodiment.

[0174] Referring to FIG. 18, a transfer method of a light-emitting element (100) according to one embodiment may include the step of providing an epitaxial substrate (20) and a first intermediate substrate (1) (2000).

[0175] As described above, the first relay substrate (1) may include a light blocking portion (14), and the light blocking portion (14) may be a light blocking agent (14a) included in the first catch layer (13) or a light blocking layer (14b) provided between the first ablation layer (12) and the first catch layer (13).

[0176] For example, the step of providing the epi substrate (20) may include the step of loading the epi substrate (20) onto the first stage (203). Additionally, the step of providing the first relay substrate (1) may include the step of loading the first relay substrate (1) onto the second stage (204).

[0177] A transfer method for a light-emitting element (100) according to one embodiment may include the step of transferring a light-emitting element (100) provided on an epitaxial substrate (20) to a first intermediate substrate (1) (2100).

[0178] For example, by irradiating laser light emitted from a laser transfer device (200) toward an epi substrate (20), a light-emitting element (100) provided on the epi substrate (20) can be seated and fixed on the first catch layer (13) of the first intermediate substrate (1).

[0179] Afterwards, the epi substrate (20) and the first intermediate substrate (1) are each unloaded from the first stage (203) and the second stage (204), and an etching process can be performed on the first intermediate substrate (1) on which the light-emitting element (100) has been transferred.

[0180] A method for transferring a light-emitting element (100) according to one embodiment may include the step of transferring the light-emitting element (100) transferred to a first intermediate substrate (1) to a second intermediate substrate (50) (2200).

[0181] For example, after loading the first relay substrate (1) on which the light-emitting element (100) has been transferred onto the first stage (203) and the second relay substrate (50) onto the second stage (204), the light-emitting element (100) can be secured and fixed to the second catch layer (53) of the second relay substrate (50) by irradiating the laser light emitted from the laser transfer device (200) toward the first transparent substrate (11).

[0182] Afterwards, the first relay substrate (1) and the second relay substrate (50) are each unloaded from the first stage (203) and the second stage (204), respectively, and an etching process can be performed on the second relay substrate (50) on which the light-emitting element (100) has been transferred.

[0183] A method for transferring a light-emitting element (100) according to one embodiment may include the step of transferring the light-emitting element (100) transferred to a second intermediate substrate (50) to a target substrate (60) (2300).

[0184] For example, after loading a second relay substrate (50) on which a light-emitting element (100) has been transferred onto a first stage (203) and a target substrate (60) onto a second stage (204), the light-emitting element (100) can be placed on the electrode layer (62) of the target substrate (60) by irradiating a laser light emitted from a laser transfer device (200) toward a second transparent substrate (51).

[0185] Afterwards, the second relay substrate (50) and the target substrate (60) are each unloaded from the first stage (203) and the second stage (204), and an etching process can be performed on the target substrate (60) on which the light-emitting element (100) has been transferred.

[0186] In addition, a bonding process can be performed so that the light-emitting element (100) is fixed on the electrode layer (62).

[0187] Meanwhile, the disclosed embodiments may be implemented in the form of a recording medium that stores instructions executable by a computer. The instructions may be stored in the form of program code and, when executed by a processor, may generate a program module to perform the operation of the disclosed embodiments. The recording medium may be implemented as a computer-readable recording medium.

[0188] Computer-readable recording media include all types of recording media that store instructions that can be decoded by a computer. Examples include ROM (read-only memory), RAM (random access memory), magnetic tape, magnetic disk, flash memory, optical data storage devices, etc.

[0189] Additionally, computer-readable recording media may be provided in the form of non-transitory storage media. Here, 'non-transitory storage media' simply means that it is a tangible device and does not contain a signal (e.g., electromagnetic waves), and this term does not distinguish between cases where data is stored semi-permanently and cases where it is stored temporarily. For example, 'non-transitory storage media' may include a buffer in which data is stored temporarily.

[0190] According to one embodiment, the method according to the various embodiments disclosed herein may be provided as included in a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a device-readable recording medium (e.g., compact disc read-only memory (CD-ROM)), or distributed online (e.g., download or upload) through an application store (e.g., Play Store™) or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product (e.g., downloadable app) may be temporarily stored or temporarily created on a device-readable recording medium, such as the memory of a manufacturer's server, an application store's server, or a relay server.

[0191] As described above, the disclosed embodiments have been explained with reference to the attached drawings. Those skilled in the art will understand that the present invention may be practiced in forms different from the disclosed embodiments without changing the technical spirit or essential features of the invention. The disclosed embodiments are illustrative and should not be interpreted restrictively.

Claims

1. Transparent substrate; An ablation layer provided on the above transparent substrate; A catch layer provided on the ablation layer and for mounting a light-emitting element; and A relay substrate comprising: a light blocking portion for preventing laser light irradiated to the catch layer from being transmitted to the ablation layer.

2. In Paragraph 1, The above light blocking unit is, A relay substrate that is a light blocker included in the above catch layer.

3. In Paragraph 2, The above light blocker is, A relay substrate that absorbs laser light of a predetermined wavelength irradiated by the above catch layer.

4. In Paragraph 2, The content of the light blocker in the above catch layer is, A relay substrate having a content of at least a predetermined amount.

5. In Paragraph 1, The above light blocking unit is, A relay substrate comprising a light-blocking layer provided between the ablation layer and the catch layer.

6. In Paragraph 1, The above light blocking unit is, A relay substrate comprising a light-blocking layer provided on the catch layer.

7. Step of laminating an ablation layer on a transparent substrate; A step of stacking a catch layer for mounting a light-emitting element on the above ablation layer; and A method for manufacturing a relay substrate comprising the step of forming a light blocking portion to prevent laser light irradiated by the catch layer from being transmitted to the ablation layer.

8. In Paragraph 7, The step of forming the light blocking portion above is, A method for manufacturing a relay substrate comprising the step of adding a light blocking agent to the catch layer.

9. In Paragraph 8, The step of adding the light blocking agent to the above catch layer is, A method for manufacturing a relay substrate comprising the step of adding a light blocking agent to the catch layer capable of absorbing laser light of a predetermined wavelength irradiated onto the catch layer.

10. In Paragraph 8, The step of adding the light blocking agent to the above catch layer is, A method for manufacturing a relay substrate comprising the step of adding a light blocking agent to a catch layer such that the content of the light blocking agent in the catch layer is greater than or equal to a predetermined content.

11. In Paragraph 7, The step of forming the light blocking portion above is, The method includes the step of laminating a light-blocking layer on the above ablation layer; The step of stacking the above catch layer is, A method for manufacturing a relay substrate comprising the step of laminating the catch layer on the light-blocking layer.

12. In Paragraph 7, The step of forming the light blocking portion above is, A method for manufacturing a relay substrate comprising the step of laminating a light-blocking layer on the catch layer.

13. A step of providing a first intermediate substrate comprising a transparent substrate, an ablation layer provided on the transparent substrate, a catch layer provided on the ablation layer for mounting a light-emitting element, and a light blocking portion for preventing laser light irradiated onto the catch layer from being transmitted to the ablation layer; A step of transferring a light-emitting element provided on an epitaxial substrate to the first intermediate substrate; A step of transferring a light-emitting element transferred to the first relay substrate to a second relay substrate; and A method for transferring a light-emitting element, comprising the step of transferring the light-emitting element transferred to the second relay substrate to a target substrate.

14. In Paragraph 13, The above light blocking unit is, A method for transferring a light-emitting element comprising a light blocker included in the above catch layer.

15. In Paragraph 13, The above light blocking unit is, A method for transferring a light-emitting element comprising a light-blocking layer provided between the ablation layer and the catch layer.

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