TW202310323A - Led relocation member and method of manufacturing led device - Google Patents

Abstract

An LED relocation member has a region where an adhesive strength is reduced by irradiation of light on at least a part of a surface thereof, and a tensile strength of the LED relocation member at 50 °C is 1 MPa to 10 MPa. A method of manufacturing an LED device is a method wherein the LED relocation member is used.

Description

Method for manufacturing LED transfer member and LED device

The invention relates to a method for manufacturing an LED transfer member and an LED device.

For image display devices using LEDs (Light Emitting Diodes, light-emitting diodes), LED packages (chip LEDs, LED chips) with a size of about 1mm or more have been used in the past, and LED elements are constructed by wire bonding. formed on the substrate. From the viewpoint of high pixel density and high response speed of image display devices, the following method has been used in recent years: Flip chip the submillimeter light-emitting diode (Mini LED) element or micro light-emitting diode (Micro LED) components are constructed on the substrate of the image display device. Generally speaking, Micro LED devices can be fabricated on crystal growth substrates such as sapphire substrates by epitaxial growth. In order to construct the Micro LED element on the substrate of the image display device, it is first necessary to separate the substrate for crystal growth from the Micro LED element by the laser lift-off (LLO, Laser Lift-off) step from the substrate for crystal growth (for example, refer to Patent Document 1). After separating the Micro LED element from the crystal growth substrate, picking up the Micro LED element and aligning the position, the Micro LED element is assembled on the substrate of the image display device. When separating the Micro LED element from the crystal growth substrate by LLO, in order to prevent the scattering of the Micro LED element, a transfer member is attached to the surface of the crystal growth substrate on the side where the Micro LED element is formed. Micro LED elements separated from the substrate for crystal growth are temporarily fixed on the surface of the transfer member to prevent scattering. Furthermore, the so-called Micro LED element in the present invention refers to an LED element whose length of each side is less than 100 μm. [Prior Art Literature] (patent documents)

Patent Document 1: Japanese Patent Laid-Open No. 2015-23240.

[Problem to be solved by the invention] Micro LED components are very small and thin, so they are prone to cracks and difficult to handle. Although the Micro LED element is fixed on the substrate for crystal growth, it is difficult to generate cracks, etc., but when it is separated from the substrate for crystal growth by LLO, positional displacement, cracks, etc. may occur due to weak external forces such as static electricity. . In addition, even with a transfer member that can solve the above-mentioned technical problems when performing LLO, if the Micro LED device is not temporarily fixed with an appropriate adhesive force, sometimes pick-up failures from the transfer member of the Micro LED device may still occur. , For poor transfer of the substrate, etc. In addition, the Micro LED element fabricated on the substrate for crystal growth can be diced by etching or the like. For the purpose of cost reduction, many Micro LED elements are produced on the substrate for crystal growth, so the interval between each Micro LED element is generally set to a very narrow width of several tens of μm. Therefore, when using a pick-up method to pick up Micro LED components, it is expected that the interval between each Micro LED component is relatively loose. Furthermore, when assembling Micro LED elements on the substrate of an image display device, for example, when red, blue, and green Micro LED elements are arranged on the substrate, it is necessary to separate the blue Micro LED elements from each other with a distance of more than 100 μm. When using a die bonder or the like to mount Micro LED elements on a substrate at intervals, it may take a long time and lower productivity. The present invention is made in view of the above-mentioned conventional situation. According to an aspect of the present invention, the problem to be solved is to provide an LED transfer member and a method of manufacturing an LED device using the LED transfer member. The transfer rate and elongation of the Micro LED element in the laser lift-off method are excellent. [Technical means to solve the problem]

Specific means for solving the foregoing technical problems are as follows. <1> An LED transfer member having, at least a part of the surface, a region where the adhesive force is reduced by light irradiation, and the LED transfer member has a tensile strength at 50° C. of 1 MPa to 10 MPa. <2> The LED transfer member according to <1>, which has a substrate and an adhesive layer arranged on the substrate, and the adhesive layer is a region where the adhesive force is reduced by light irradiation. <3> The LED transfer member according to <1> or <2>, wherein the adhesive force of the region where the adhesive force is reduced is 0.7 N/25 mm or less after light irradiation. <4> A method of manufacturing an LED device using the LED transfer member according to any one of <1> to <3>. <5> A method for manufacturing an LED device, comprising the following steps: The surface on the side of the LED transfer member described in any one of <1> to <3> that has the area where the adhesive force will be reduced is brought into contact with the side of the optical device substrate on which the LED element is formed, so that the LED is transferred A member is attached to the optical device substrate to form an attached body, the optical device substrate has a substrate for crystal growth, a buffer layer formed on the substrate for crystal growth, and an LED element formed on the buffer layer, the buffer layer With this LED element being in a state divided for each device, irradiating laser light to the aforementioned buffer layer to destroy the aforementioned buffer layer, transferring the aforementioned LED element to the aforementioned LED transfer member by separating the aforementioned substrate for crystal growth from the aforementioned LED transfer member, Extending the aforementioned LED transfer member to expand the distance between the aforementioned LED elements that have been transferred to the aforementioned LED transfer member, The stretched LED transfer member is irradiated with light to reduce the adhesive force of the LED transfer member. <6> The method for manufacturing an LED device according to <5>, wherein the length of the long side of the LED element is 100 μm or less.

[Effect of the invention] According to one aspect of the present invention, it is possible to provide an LED transfer member which is excellent in transfer rate and extensibility of Micro LED elements in a laser lift-off method and a method of manufacturing an LED device using the LED transfer member.

Hereinafter, the form for carrying out this invention is demonstrated in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, unless otherwise specified, the constituent elements (including elemental steps, etc.) are not essential. The same applies to numerical values and their ranges, which are not intended to limit the present invention.

The term "step" in the present invention is included in the step as long as it can achieve the purpose of the step when it cannot be clearly distinguished from the other step except for the independent step. Regarding the numerical range represented by "-" in the present invention, the numerical values described before and after "-" are included as the minimum value and the maximum value, respectively. Regarding the numerical ranges described stepwise in the present invention, the upper limit or lower limit described in one numerical range may be replaced by the upper limit or lower limit of another numerical range described stepwise. In addition, about the numerical range described in this invention, the upper limit or the lower limit of the numerical range can be replaced with the value shown in an Example. In the present invention, each component may contain a plurality of substances corresponding to the component. When a plurality of substances corresponding to each component exist in the composition, unless otherwise specified, the content or content of each component means the total content or total content of the plurality of substances present in the composition. The term "layer" or "film" in the present invention, when looking at the region where the layer or film exists, includes not only the case where the layer or film is formed in the entire region, but also the case where it is formed in only a part of the region. The term "lamination" in the present invention means that layers are accumulated and superimposed, and two or more layers may be bonded together, or two or more layers may be separated. The "(meth)acryl" in the present invention means at least one of acryl and methacryl. In the present invention, the thicknesses of five points of the target layer or film are measured, and the arithmetic mean thereof is regarded as the average thickness of the layer or film. The thickness of the layer or film can be measured using a micrometer or the like. In the present invention, when the thickness of a layer or film can be directly measured, it is measured using a micrometer. On the other hand, when measuring the thickness of a single layer or the total thickness of a plurality of layers, it can be measured by observing the cross-section of the measurement object using an electron microscope.

＜LED Transfer Member＞ In the LED transfer member of the present invention, at least a part of the surface has a region where the adhesive force will be reduced by light irradiation, and the tensile strength of the LED transfer member at 50° C. is 1 MPa˜10 MPa. Hereinafter, the LED transfer member of the present invention may be simply referred to as a "transfer member". According to the LED transfer member of the present invention, it is excellent in the transfer rate of Micro LED in the LLO method. The reason for this is not clear, but it is presumed as follows. The LED transfer member of the present invention has a region where the adhesive force will be reduced by light irradiation. Compared with after light irradiation, the LED element attached to this region before light irradiation will be firmly held by the transfer member, while in the LLO method In this case, it becomes possible to separate the LED element from the substrate for crystal growth. In addition, it is possible to suppress cracks, misalignment, and the like that occur due to a weak external force during the LLO method. Therefore, the transfer rate from the crystal growth substrate to the LED transfer member can be improved. On the other hand, after light irradiation, the adhesive force of this area will be reduced, so the LED element temporarily fixed to this area can be picked up easily. Therefore, the transfer rate from the LED transfer member can be improved. Based on the above circumstances, it can be speculated that the LED transfer member according to the present invention can improve the transfer rate of Micro LED in the LLO method. Furthermore, in the present invention, the tensile strength of the transfer member at 50° C. is 1 MPa to 10 MPa. As long as the transfer member has a tensile strength of 1 MPa or more at 50° C., there is a tendency that when the transfer member is stretched, the force to expand the interval between the Micro LED elements transferred to the transfer member becomes sufficient, and it is possible to easily Greatly expand the pitch of Micro LED components. As long as the tensile strength of the transfer member at 50° C. is 10 MPa or less, the extension of the transfer member by a crystal expander or the like tends to be easy. The tensile strength of the transfer member at 50°C is preferably from 2MPa to 9MPa, more preferably from 3MPa to 8MPa. The tensile strength of the transfer member at 50° C. means a value measured at 50° C. and a tensile speed of 5 mm/s using a test piece with a width of 20 mm and a tensile testing machine.

The layer configuration of the transfer member is not particularly limited, and may be a single layer or two or more layers. When the transfer member has more than two layers, the material constituting one side of the transfer member and the material constituting the other side can be properly selected, and the adhesive force of one side and the other side of the transfer member can be adjusted. Therefore, the adhesive force on one side of the transfer member is increased, and the other side does not exhibit adhesive force in the temperature range where the LLO method is performed, thereby improving the process suitability of the transfer member. Hereinafter, the LED transfer member of the present invention will be described with reference to the drawings. In addition, the LED transfer member of this invention is not limited to the following embodiment. In addition, the dimension of members in each figure is a conceptual representation only, and the relative relationship of the dimension between members is not limited to this. In addition, in each drawing, the same code|symbol is attached|subjected to the same member, and overlapping description may be abbreviate|omitted.

FIG. 1 is a cross-sectional view of a transfer member 10 having a double-layer structure. In FIG. 1 , the transfer member 10 has a base material 12 and an adhesive layer 14 disposed on the base material 12 . The adhesive layer 14 corresponds to a region where the adhesive force is reduced by light irradiation. Substrate 12 can be following various plastic films: polyester films such as polyethylene terephthalate film; Polytetrafluoroethylene film, polyethylene film, polypropylene film, polymethylpentene film, polyvinyl acetate film Ester films; polyolefin-based films comprising homopolymers of α-olefins such as poly-4-methylpent-1-ene and their copolymers, and ionomers comprising the above-mentioned homopolymers or the above-mentioned copolymers; Polyvinyl chloride film; polyimide film; urethane resin film, etc. The substrate 12 is not limited to a single layer, but may be a multilayer film obtained by combining two or more of the above-mentioned plastic films, or two or more layers of the same type of plastic film.

The substrate 12 is preferably a polyolefin-based film or an urethane resin-based film from the viewpoint of stretchability. The base material 12 may contain various additives such as an anti-blocking agent as needed.

The average thickness of the base material 12 should just be set suitably as needed. The average thickness of the substrate 12 is preferably 50 μm to 500 μm. As long as the average thickness of the base material 12 is 50 μm or more, there is a tendency that the reduction in the extensibility of the transfer member can be suppressed. As long as the average thickness of the base material 12 is 500 μm or less, there is a tendency to suppress deformation of the transfer member when the transfer member is stretched. As long as there is no problem with the handleability of the transfer member, the substrate 12 is preferably thin from the viewpoint of cost, more preferably 50 μm to 400 μm, further preferably 50 μm to 300 μm. However, when a high-energy ray (among these, ultraviolet rays) curable adhesive is used as the adhesive constituting the adhesive layer 14 , the average thickness of the substrate 12 is preferably a thickness that does not hinder the penetration of high-energy ray. From such a viewpoint, it is preferably 50 μm to 500 μm, more preferably 50 μm to 300 μm. When the base material 12 is composed of the film-like multi-layer base material described above, it is preferable to adjust so that the average thickness of the base material 12 as a whole falls within the range described above.

In order to improve the adhesiveness with the adhesive 14, the base material 12 may be chemically or physically surface-treated as needed. Examples of the surface treatment include corona treatment, chromic acid treatment, ozone exposure, flame exposure, high-voltage shock exposure, and ionizing radiation treatment.

The adhesive layer 14 is not particularly limited as long as it has the property that the adhesive force is lowered by light irradiation.

The adhesive layer 14 is preferably composed of an adhesive component that has adhesive force to the LED element on the substrate for crystal growth at 25°C. Examples of the base resin constituting the adhesive component of the adhesive layer 14 include acrylic resins, various synthetic rubbers, natural rubbers, polyimide resins, and the like. Among these, acrylic resins are preferred. From the viewpoint of reducing the residual adhesive of the adhesive component, the above-mentioned base resin preferably has a functional group such as a hydroxyl group and a carboxyl group that can react with a crosslinking agent described later.

Based on functional groups such as hydroxyl groups and carboxyl groups contained in the base resin, (meth)acryl groups can be introduced into the base resin. For the hydroxyl group contained in the base resin, it can be reacted with a compound containing a functional group reactive with a hydroxyl group and a (meth)acryl group such as 2-methacryloxyethyl isocyanate to make the base resin Resin introduces (meth)acryl groups. In addition, the carboxyl group contained in the base resin can be reacted with a compound containing a functional group reactive with a carboxyl group and a (meth)acryl group, such as glycidyl methacrylate, to introduce (meth)acryl groups into the base resin. ) acryl group. When such a curable resin is used as the base resin, the base resin can be cured by light irradiation, thereby reducing the adhesive force of the adhesive layer 14 .

In addition, in order to adjust the adhesive force of the adhesive layer 14 , the adhesive component may include a cross-linking agent capable of cross-linking with the functional group of the base resin. The type of crosslinking agent is not particularly limited, and can be selected according to the type of base resin and the like. Specifically, isocyanate crosslinking agent, melamine crosslinking agent, peroxide crosslinking agent, metal alkoxide crosslinking agent, metal chelate crosslinking agent, metal salt crosslinking agent, carbodiimide crosslinking agent agent, oxazoline crosslinking agent, aziridine crosslinking agent, amine crosslinking agent, etc. These crosslinking agents may be used alone or in combination of two or more. Among the above crosslinking agents, an isocyanate crosslinking agent is preferred from the viewpoint of stable adhesive properties. In addition, when the reaction speed between the base resin and the crosslinking agent is slow, catalysts such as amines and tin-based compounds can be used as needed.

The isocyanate crosslinking agent is not particularly limited, and can be selected from known compounds having isocyanate groups (isocyanate compounds). From the viewpoint of reactivity, difunctional isocyanate compounds (compounds having two isocyanate groups) and polyfunctional isocyanates (compounds having three or more isocyanate groups) are preferred, and polyfunctional isocyanate compounds are more preferred.

In addition, in order to properly adjust the adhesive properties of the adhesive layer 14, the adhesive component may appropriately contain optional components such as tackifiers such as rosin-based and terpene-based resins, various surfactants, and the like.

When the base resin contains a (meth)acryl group, in order to harden the base resin by light irradiation, the adhesive layer 14 may contain a photopolymerization initiator. The photopolymerization initiator is not particularly limited as long as it can be decomposed by photoirradiation to generate free radicals, thereby starting the polymerization of the base resin. The type and content of the photopolymerization initiator can be appropriately selected based on the wavelength of light irradiated on the adhesive layer 14 , the intensity of light, the amount of (meth)acryl group contained in the base resin, and the like.

Since the components contained in the adhesive layer 14 are volatilized to prevent contamination and destruction of the LED element, the content of components having a boiling point or sublimation point below 100° C. in the adhesive layer 14 is relatively low relative to the entire adhesive layer 14 . Preferably, it is 5 mass % or less, More preferably, it is 3 mass % or less, More preferably, it is 1.5 mass % or less. The boiling point or sublimation point of each component contained in the adhesive layer 14 can be calculated|required by thermogravimetric measurement, for example.

The average thickness of the adhesive layer 14 is preferably 1 μm to 100 μm, more preferably 2 μm to 50 μm, further preferably 5 μm to 40 μm. By setting the average thickness of the adhesive layer to 1 μm or more, sufficient adhesive force with the LED element can be secured. On the other hand, from the viewpoint of economic efficiency, the average thickness of the adhesive layer 14 is preferably 100 μm or less.

The adhesive force of the adhesive layer 14 after light irradiation is preferably 0.7 N/25 mm or less, more preferably 0.5 N/25 mm or less, and further preferably 0.5 N/25 mm or less from the viewpoint of suppressing a reduction in the transfer rate of the LED element from the transfer member. The best is 0.4N/25mm or less, and the most preferred is 0.3N/25mm or less. The adhesive force of the adhesive layer 14 after light irradiation may be 0.01 N/25 mm or more from the viewpoint of suppressing displacement of the LED element. The adhesive force of the adhesive layer 14 before light irradiation is preferably at least 0.8 N/25 mm, more preferably at least 1.0 N/25 mm, from the viewpoint of holding the LED element on the adhesive layer 14 more stably during the LLO step, More preferably, it is 1.2N/25mm or more. The adhesive force of the adhesive layer 14 before light irradiation may be 5.0 N/25mm or less. The adhesive force of the adhesive layer 14 means the peeling strength with stainless steel (SUS). The adhesive force can be a value obtained by measuring the peel strength by a method based on Japanese Industrial Standard JIS C 5016:1994 (tear strength of conductor).

FIG. 2 is a cross-sectional view of a single-layer transfer member 20 . The transfer member 20 as a whole corresponds to a region where the adhesive force is reduced by light irradiation. The components constituting the single-layer transfer member 20 can be the same as those of the adhesive layer 14 constituting the transfer member 10 shown in FIG. 1 . Furthermore, the transfer member 20 does not have a base material, so in order to enhance the strength of the transfer member 20 itself, it is preferable that the components constituting the transfer member 20 have higher mechanical strength than the adhesive layer 14 . For example, it is preferable to increase the addition amount of the crosslinking agent or increase the addition amount of the catalyst compared with the adhesive layer 14 . At the peripheral portion of the transfer member 20, an outer frame-shaped structure for reinforcing the transfer member 20 may be disposed.

The manufacturing method of the transfer member is not particularly limited, and can be manufactured according to known techniques in this technical field. For example, the transfer member 10 having a two-layer structure can be produced by the following method. A coating liquid containing the constituents of the adhesive layer and a solvent is coated on the protective film by knife coating, roll coating, spray coating, gravure coating, bar coating, or curtain coating, and then The solvent is removed to form an adhesive layer. Specifically, it is preferable to perform heating under conditions of 50° C. to 200° C. and 0.1 minutes to 90 minutes for removal of the solvent. Drying conditions are preferably conditions such that the organic solvent in the adhesive layer evaporates to 1.5% by mass or less as long as voids do not occur in the coating step and drying step, and the viscosity adjustment of the coating liquid is not affected. Under the temperature condition of normal temperature to 60°C, the prepared adhesive layer protective film and the base material are laminated so that the adhesive layer and the base material face each other, and they are laminated using a roll laminator, etc. layer-constructed transfer components. The protective film can be removed when the transfer member 10 is used. In addition, by peeling off the protective film from the adhesive layer protective film, a single-layer transfer member can be obtained.

As a film that can be suitably used as a protective film, for example: A-63 (release treatment agent: modified silicon oxide system) manufactured by Teijin DuPont Film Co., Ltd., Teijin DuPont Film Co., Ltd. A-31 (release treatment agent: platinum-based silicone-based), etc.

The average thickness of the protective film can be appropriately selected within a range that does not impair workability, but generally, it is preferably 100 μm or less from the viewpoint of economic efficiency. The average thickness of the protective film is more preferably in the range of 10 μm to 75 μm, further preferably in the range of 25 μm to 50 μm. As long as the average thickness of the protective film is 10 μm or more, defects such as cracking of the protective film tend to be less likely to occur when producing the transfer member. In addition, as long as the average thickness of the protective film is 100 μm or less, the protective film tends to be easily peelable when using a transfer member.

<Manufacturing method of LED device> The manufacturing method of the LED device of this invention uses the LED transfer member of this invention. The method of manufacturing the LED device of the present invention is not particularly limited as long as the LED transfer member of the present invention is used. The LED transfer member of the present invention has at least a part of the surface where the adhesive force will be reduced by light irradiation. Therefore, in the manufacturing method of the LED device of the present invention, it is preferable to implement light irradiation at least at any stage to make the transfer member Decreased adhesion. One embodiment of the manufacturing method of the LED device of the present invention may include the following steps: bringing the surface of the LED transfer member of the present invention on the side having the region where the adhesive force is reduced, into contact with the side of the optical device substrate on which the LED element is formed. , making the aforementioned LED transfer member attached to the aforementioned optical device substrate to form an attached body, the aforementioned optical device substrate having a substrate for crystal growth, a buffer layer formed on the substrate for crystal growth, and an LED formed on the buffer layer. element, the buffer layer and the LED element are in a state of being divided for each device, irradiating laser light to the aforementioned buffer layer to destroy the aforementioned buffer layer, transferring the aforementioned LED element to the aforementioned LED transfer member by separating the aforementioned substrate for crystal growth from the aforementioned LED transfer member, Extending the aforementioned LED transfer member to expand the distance between the aforementioned LED elements that have been transferred to the aforementioned LED transfer member, The stretched LED transfer member is irradiated with light to reduce the adhesive force of the LED transfer member. The method for manufacturing an LED device of the present invention is suitable for manufacturing a Micro LED element in which the length of the long side of the LED element is 100 μm or less.

Hereinafter, an example of the manufacturing method of the LED device using the LED transfer member of this invention is demonstrated based on drawing. In the following description, the case of using the transfer member 10 having the double-layer structure shown in FIG. 1 will be described as an example, but the layer configuration of the transfer member is not particularly limited. FIG. 3 is a cross-sectional view of the optical device substrate 30 . The optical device substrate 30 has: a substrate 32 for crystal growth; and, in a divided state for each device, a buffer layer 34 formed on the substrate 32 for crystal growth and an LED element (Micro LED) formed on the buffer layer 34 . element).

The substrate 32 for crystal growth serves as a matrix for forming the LED element 36 on the surface thereof. Examples of the substrate 32 for crystal growth include sapphire (AlO), SiC, Si, GaAs, GaN, MgAl ₂ O ₄ and the like. For forming the crystal of the GaN-based semiconductor used in blue LEDs, sapphire, SiC, Si, GaN-based substrates, and the like are preferable from the viewpoint of crystal growth properties. For the growth of AlInGaP-based or AlGaAs-based crystals used in red LEDs, GaAs-based substrates are preferred from the viewpoint of crystal growth properties.

The buffer layer 34 is a layer that can be destroyed by irradiation of laser light, and functions as a separation layer for separating the LED element 36 from the substrate 32 for crystal growth. The components constituting the buffer layer 34 can be appropriately selected based on the components of the crystal growth substrate 32 and the LED element 36 . In addition, the method for forming the buffer layer 34 is not particularly limited.

The LED element 36 has the light-emitting characteristics of Micro LED, and is formed by the LPE method (Liquid Phase Epitaxy, liquid phase epitaxy growth method), MOVPE (Metal Organic Vapor Phase Epitaxy, metal organic vapor phase epitaxy growth) method, molecular beam epitaxy It is formed on the substrate 32 for crystal growth by a method such as Molecular Beam Epitaxy: MBE. The composition of the LED element 36 can include, for example: aluminum gallium arsenide (AlGaAs): red; gallium phosphide (GaAsP): red/orange/yellow; indium gallium nitride (InGaN)/gallium nitride (GaN)/aluminum nitride Gallium (AlGaN): orange/yellow/green/blue/violet; gallium phosphide (GaP): red/yellow/green; zinc selenide (ZnSe): green/blue; and, aluminum indium gallium phosphide (AlGaInP): orange /orange/yellow/green.

Bumps 38 , which are conductive protrusions, may be provided on the LED element 36 . As the material of the bump, gold; silver; copper; tin-silver, tin-lead, tin-bismuth, tin-copper solder; tin; nickel; The bump 38 may be composed of a single component or may be composed of a plurality of components. When the bump 38 is composed of multiple components, the metal components may be formed in a laminated structure.

As shown in FIG. 4 , in the manufacturing method of the LED device, the transfer member 10 is attached to the optical device by bringing the adhesive layer 14 side of the transfer member 10 into contact with the side of the optical device substrate 30 on which the LED element 36 is formed. substrate 30 to obtain an attached body 40 . The method of attaching the transfer member 10 to the optical device substrate 30 is not particularly limited, and conventionally known lamination methods can be used. As a lamination method, a lamination method using a roll laminator, a diaphragm laminator, a vacuum roll laminator, a vacuum diaphragm laminator, etc. is mentioned.

Lamination conditions may be appropriately set based on the physical properties and characteristics of the optical device substrate 30 and the transfer member 10 . For example, as long as it is a roll lamination machine, the lamination temperature is preferably room temperature (25°C) to 200°C, more preferably room temperature (25°C) to 150°C, and still more preferably room temperature (25°C). ~100°C. As long as the lamination temperature is 25° C. or higher, the transfer member 10 can be firmly attached to the optical device substrate 30. Therefore, when the transfer member 10 is separated from the crystal growth substrate 32 after irradiating the buffer layer 34 with laser light, the There is a tendency to prevent the LED element 36 from detaching from the transfer member 10, the positional displacement of the LED element 36, and the like. As long as the lamination temperature is 200° C. or lower, a difference in thermal expansion between the transfer member 10 and the optical device substrate 30 is unlikely to occur, and deformation, looseness, etc. due to lower elasticity of the base material 12 constituting the transfer member 10 are less likely to occur. , and therefore tends to prevent positional shift of the LED element 36 and the like. In the case of a diaphragm type laminator, the relevant temperature conditions are the same as those for the above-mentioned roll laminator. The crimping time is preferably from 5 seconds to 300 seconds, more preferably from 5 seconds to 200 seconds, further preferably from 5 seconds to 100 seconds. As long as the pressure-bonding time is 5 seconds or more, the transfer member 10 can be firmly attached to the optical device substrate 30, so when the transfer member 10 is separated from the crystal growth substrate 32 after the buffer layer 34 is irradiated with laser light, the There is a tendency to prevent the LED element 36 from detaching from the transfer member 10, the positional displacement of the LED element 36, and the like. If the crimping time is 200 seconds or less, the productivity of the LED device tends to be improved. The lamination pressure is preferably from 0.1 MPa to 3 MPa, more preferably from 0.1 MPa to 2 MPa, further preferably from 0.1 MPa to 1 MPa. As long as the lamination pressure is 0.1 MPa or more, the transfer member 10 can be firmly attached to the optical device substrate 30. Therefore, when the transfer member 10 is separated from the crystal growth substrate 32 after irradiating the buffer layer 34 with laser light, the There is a tendency to prevent the LED element 36 from detaching from the transfer member 10, the positional displacement of the LED element 36, and the like. If the lamination pressure is 3 MPa or less, it tends to be possible to prevent breakage of the LED element 36 due to pressure applied to the LED element 36 and suppress the occurrence of cracks and the like.

Next, as shown in FIG. 5 , the buffer layer 34 is irradiated with laser light 50 . In FIG. 5, the buffer layer 34 is irradiated with laser light 50 from the side opposite to the side on which the LED element 36 is formed in the optical device substrate 30, but the irradiation direction of the laser light 50 is not particularly limited, and may be transferred from the transfer member. The substrate 12 side in 10 irradiates the buffer layer 34 with laser light 50 . By irradiating the buffer layer 34 with laser light 50 , the buffer layer 34 is destroyed.

As the laser, there are excitation light source laser (xenon flash lamp, etc.) using an arc lamp as the excitation light source, diode excitation laser (LD excitation) excited by LD (Laser Diode), and the like. For the medium, there are solids, gases, semiconductors, etc. Generally speaking, solids use YAG lasers (YAG rods composed of yttrium (Y), aluminum (A), and garnet (G)), and gases (gas) use quasi- Molecular laser (Excimer Laser), CO ₂ laser, etc. Generally, a diode-pumping laser can be used as a solid-state laser (diode-pumping solid-state laser: DPSS laser) (DPSS: Diode Pumping Solid-State). Compared with excimer lasers, DPSS lasers are more suitable in terms of low cost and easy maintenance and management.

Next, as shown in FIG. 6 , the crystal growth substrate 32 is separated from the transfer member 10 . At this time, the LED element 36 formed on the substrate 32 for crystal growth is transferred in a state of being attached to the adhesive layer 14 in the transfer member 10 .

Next, as shown in FIG. 7 , the transfer member 10 is extended. In FIG. 7 , the transfer member 10 extends in the plane direction of the transfer member indicated by the arrow in FIG. 7 . By extending the transfer member 10, the intervals between the LED elements 36 can be expanded in the surface direction of the transfer member. When the transfer member 10 is extended, the LED element 36 is in the state of being attached to the adhesive layer 14 in the transfer member 10, so there is a tendency to prevent the LED element 36 from being detached from the transfer member 10, and the position of the LED element 36 is displaced. wait.

The extending method of the transfer member 10 is not particularly limited, for example, there are lifting and stretching methods. The lifting method is a method in which the transfer member 10 is pulled apart by raising a stage formed in a specific shape after fixing the transfer member 10 . The stretching method is a method in which after fixing the transfer member 10, the transfer member 10 is pulled apart by stretching the installed transfer member 10 in parallel to a specific direction. The elevating method is preferable in terms of making the LED elements 36 evenly spaced and making the required (occupied) device area smaller and denser.

The stretching conditions may be appropriately set according to the characteristics of the transfer member 10 . For example, the lifting amount or stretching amount is preferably from 10 mm to 500 mm, more preferably from 10 mm to 300 mm. If the lifting amount or the stretching amount is 10 mm or more, the distance between the LED elements 36 tends to be sufficiently expanded. If the lifting amount or the stretching amount is 500 mm or less, it tends to be possible to prevent scattering, misalignment, and the like of the LED element 36 . The temperature at the time of stretching may be appropriately set according to the characteristics of the transfer member 10 . For example, the temperature during stretching is preferably from 10°C to 200°C, more preferably from 10°C to 150°C, further preferably from 20°C to 100°C. As long as the stretching temperature is 10° C. or higher, the transfer member 10 tends to be easily stretchable. If the temperature at the time of stretching is 200° C. or lower, it tends to be possible to prevent thermal expansion of the transfer member 10 , deformation due to low elasticity, looseness, etc., and to prevent scattering and misalignment of the LED elements 36 . The stretching speed may be appropriately set according to the characteristics of the transfer member 10 . For example, the stretching speed is preferably 0.1 mm/sec to 500 mm/sec, more preferably 0.1 mm/sec to 300 mm/sec, further preferably 0.1 mm/sec to 200 mm/sec. As long as the stretching speed is 0.1 mm/sec or more, there is a tendency that deterioration in productivity can be suppressed. Scattering of the LED element 36 tends to be suppressed as long as the stretching speed is 500 mm/sec or less.

Thereafter, the transfer member 10 is irradiated with light. Thereby, the adhesive force of the adhesive layer 14 in the transfer member 10 is reduced, so that it becomes easy to pick up the LED element 36 from the transfer member 10 .

Next, as shown in FIG. 8, pick up is performed using means 52 for picking up the LED element 36 from the transfer member 10, and as shown in FIG. sheet 56, and the bump 38 is bonded to the spacer 56 to manufacture the Micro LED.

The mounting substrate 54 on which the LED element 36 is mounted is not particularly limited as long as it is a general circuit board. The construction substrate 54 can be used as a main component: a circuit pattern is formed by etching away unnecessary parts of the metal layer formed on the surface of the substrate. The substrate is made of glass, glass epoxy resin, polyester, ceramics, epoxy resin, Bismaleimide triazine, polyimide, etc.; those that form circuit patterns on the substrate surface by metal plating; those that print conductive substances on the substrate surface to form circuit patterns, etc.

A metal layer can be formed on the surface of the circuit pattern including the spacer 56 on the construction substrate 54, and the metal layer is composed of the following components as main components: gold; silver; copper; tin-silver system, tin-lead system, Tin-bismuth, tin-copper solder; tin; nickel; indium tin oxide (ITO); indium, etc. A circuit pattern may consist of only a single component, or may consist of plural components. In addition, the circuit pattern can be made into a structure in which multiple layers of metal are laminated.

The method of picking up the LED element 36 includes a method of using a pick-up tool such as a flip-chip bonder and a die-bonding machine, and using an air pressure difference for adsorption; a method of setting an adhesive body on a pick-up tool and picking it up with adhesive force, and the like. After the LED element 36 is picked up, the position is aligned, and then assembled on the spacer 56 provided on the construction substrate 54 . The LED element 36 may also be picked up using a roll or the like provided with an adhesive.

When picking up the LED element 36 from the transfer member 10, a carrier can also be used. As shown in FIG. 6, the crystal growth substrate 32 is separated from the transfer member 10, and then the transfer member 10 is extended as shown in FIG. 7, and the carrier 60 is attached to the transfer member 10 as shown in FIG. 10. The surface on the side where the LED element 36 is transferred. The light irradiation on the transfer member 10 may be performed after extending the transfer member 10 , and may be before or after the carrier 60 is attached to the transfer member 10 .

Then, the carrier 60 is separated from the transfer member 10 . The LED components 36 can be transferred to the carrier 60 . Next, as shown in FIG. 11 , the LED element 36 transferred to the carrier 60 is mounted on the spacer 56 provided on the assembly substrate 54 , and the bump 38 is bonded to the spacer 56 to manufacture a Micro LED.

The method of transferring the LED element 36 to the carrier 60 is not particularly limited, and a conventionally known lamination method can be used. As a lamination method, a lamination method using a roll laminator, a diaphragm laminator, a vacuum roll laminator, a vacuum diaphragm laminator, etc. is mentioned.

Lamination conditions may be appropriately set based on the physical properties and characteristics of the carrier 60 and the transfer member 10 . For example, if it is a roll lamination machine, the lamination temperature is preferably room temperature (25°C) to 200°C, more preferably room temperature (25°C) to 150°C, and more preferably room temperature (25°C) to 100°C. As long as the lamination temperature is 25° C. or higher, the transfer member 10 can be firmly attached to the carrier 60 , so when the carrier 60 is separated from the transfer member 10 , there is a tendency to prevent the LED element 36 from transferring from the transfer member 10 or the carrier 60 . detachment, displacement of the position of the LED element 36, and the like. As long as the lamination temperature is 200° C. or lower, the difference in thermal expansion between the transfer member 10 and the carrier 60 is not likely to occur, and deformation, relaxation, etc. due to lower elasticity of the base material 12 constituting the transfer member 10 are not likely to occur. There is a tendency to prevent positional deviation of the LED element 36 and the like. In the case of a diaphragm type laminator, the relevant temperature conditions are the same as those for the above-mentioned roll laminator. The crimping time is preferably from 5 seconds to 300 seconds, more preferably from 5 seconds to 200 seconds, further preferably from 5 seconds to 100 seconds. As long as the crimping time is 5 seconds or more, the transfer member 10 can be firmly attached to the carrier 60, so when the carrier 60 is separated from the transfer member 10, there is a tendency to prevent the LED element 36 from transferring from the transfer member 10 or the carrier 60. detachment, displacement of the position of the LED element 36, and the like. If the crimping time is 200 seconds or less, the productivity of the LED device tends to be improved. The lamination pressure is preferably from 0.1 MPa to 3 MPa, more preferably from 0.1 MPa to 2 MPa, further preferably from 0.1 MPa to 1 MPa. As long as the lamination pressure is 0.1 MPa or more, the carrier 60 can be firmly attached to the transfer member 10. Therefore, when the carrier 60 is separated from the transfer member 10, there is a tendency to prevent the LED element 36 from the transfer member 10 or the carrier 60. detachment, displacement of the position of the LED element 36, and the like. If the lamination pressure is 3 MPa or less, it tends to be possible to prevent breakage of the LED element 36 due to pressure applied to the LED element 36 and suppress the occurrence of cracks and the like.

The carrier 60 is not particularly limited as long as it can withstand the temperature and pressure at the time of attachment, prevent the breakage of the LED elements 36 , and maintain the distance between the LED elements 36 . The carrier 60 preferably has heat resistance capable of withstanding the above lamination temperature. The material of the carrier 60 is not particularly limited, and examples thereof include silicon oxide boards, glass boards, SUS (stainless steel) boards, iron boards, Cu (copper) boards, and the like; glass epoxy boards, and the like.

The average thickness of the carrier 60 is preferably 100 μm˜5 mm, more preferably 100 μm˜4 mm, further preferably 100 μm˜3 mm. When the average thickness of the carrier 60 is 100 μm or more, handleability will be improved. Since it is expected that a thicker carrier 60 will not further improve the operability, from the viewpoint of economic benefits, as long as the average thickness of the carrier is 5 mm or less.

The carrier 60 may be composed of plural layers. In addition to the layer exhibiting the above-mentioned heat resistance and handleability, it may be a layer in which an adhesive layer or a temporary fixing material is laminated from the viewpoint of imparting adhesive force control. Adhesive force only needs to be set appropriately. From the viewpoint of transferability of the LED element 36 from the transfer member to the carrier 60 , the adhesive force imparted to the carrier 60 is preferably higher than the adhesive force of the adhesive layer 14 after light irradiation.

The method of mounting the LED element 36 from the carrier 60 to the assembly substrate 54 is not particularly limited, and conventionally known lamination methods can be used. As a lamination method, a lamination method using a roll laminator, a diaphragm laminator, a vacuum roll laminator, a vacuum diaphragm laminator, etc. is mentioned.

Lamination conditions may be appropriately set based on the physical properties and characteristics of the carrier 60 , the package substrate 54 , and the LED element 36 . For the purpose of protecting the bumps 38 , the connection between the bumps 38 and the assembly substrate 54 , and improving the reliability of the Micro LED, an underfill material can be supplied on the assembly substrate 54 in advance. If the primer filling material is supplied, the LED element 36 tends to be easily fixed on the assembly substrate 54 , and the positional displacement of the LED element 36 is less likely to occur.

For example, if it is a roll lamination machine, the lamination temperature is preferably room temperature (25°C) to 200°C, more preferably room temperature (25°C) to 150°C, and more preferably room temperature (25°C) to 100°C. As long as the lamination temperature is above 25° C., the LED element 36 can be firmly fixed to the assembly substrate 54 . Therefore, when the carrier 60 and the assembly substrate 54 are to be separated, there is a tendency to prevent the LED element 36 from the assembly substrate 54 . detachment, displacement of the position of the LED element 36, and the like. If the lamination temperature is 200° C. or lower, the difference in thermal expansion between the carrier 60 and the package substrate 54 tends to be less likely to occur, and positional displacement of the LED element 36 and the like can be prevented. In the case of a diaphragm type laminator, the relevant temperature conditions are the same as those for the above-mentioned roll laminator. The crimping time is preferably from 5 seconds to 300 seconds, more preferably from 5 seconds to 200 seconds, further preferably from 5 seconds to 100 seconds. As long as the crimping time is more than 5 seconds, the LED element 36 can be firmly fixed to the assembly substrate 54, so when the carrier 60 is separated from the assembly substrate 54, there is a tendency to prevent the LED element 36 from the assembly substrate 54. detachment, displacement of the position of the LED element 36, and the like. If the crimping time is 200 seconds or less, the productivity of the LED device tends to be improved. The lamination pressure is preferably from 0.1 MPa to 3 MPa, more preferably from 0.1 MPa to 2 MPa, further preferably from 0.1 MPa to 1 MPa. As long as the lamination pressure is 0.1 MPa or more, the LED element 36 can be firmly fixed to the assembly substrate 54. Therefore, when the carrier 60 is separated from the assembly substrate 54, there is a tendency to prevent the LED element 36 from the assembly substrate 54. detachment, displacement of the position of the LED element 36, and the like. If the lamination pressure is 3 MPa or less, it tends to be possible to prevent breakage of the LED element 36 due to pressure applied to the LED element 36 and suppress the occurrence of cracks and the like.

In addition, this invention is not limited to the specific structure of the said embodiment, Various changes are possible in the range which does not deviate from the summary of this invention.

[Example] Hereinafter, the present invention will be more specifically described based on examples, but the present invention is not limited to these examples.

(production of acrylic resin) Prepare 1000g of ethyl acetate, 650g of 2-ethylhexyl acrylate, 350g of 2-hydroxyethyl acrylate and 3.0g of azobisisobutyronitrile in a reaction kettle with a capacity of 4000ml, and stir until uniform, then use a flow rate of 100ml/ Nitrogen bubbling was carried out for 60 minutes at a speed of 1 minute to degas the residual oxygen in the system. The reactor was equipped with a three-in-one mixer, stirring blades and a nitrogen inlet pipe. The temperature was raised to 60° C. over 1 hour, and after the temperature was raised, it was polymerized for 4 hours. Thereafter, the temperature was raised to 90° C. over 1 hour, and further kept at 90° C. for 1 hour, and then cooled to room temperature. Then, 1000 g of ethyl acetate was added and stirred for dilution. After adding 0.1 g of hydroquinone as a polymerization inhibitor and 0.05 g of dioctyltin dodecanoate as an amination catalyst, 2-methacryloxyethyl isocyanate (Showa Denko Co., Ltd. Manufactured by the company, Karenz (MOI) 100 g, reacted at 70° C. for 6 hours, and then cooled to room temperature. Thereafter, ethyl acetate was added and adjusted so that the non-volatile matter content in the solution of the acrylic resin became 35% by mass, thereby obtaining a solution of an acrylic resin having a functional group capable of chain polymerization. When the acid value and hydroxyl value of the resin were measured according to Japanese Industrial Standard JIS K0070:1992, no acid value was detected. The calculated hydroxyl value was 121 mgKOH/g. The obtained acrylic resin solution was vacuum-dried overnight at 60° C., and the obtained solid content was subjected to elemental analysis with a fully automatic elemental analysis device (varioEL) manufactured by Elementar GmbH, Germany. When the content of 2-methacryloxyethyl isocyanate introduced into the acrylic resin was calculated from the measured nitrogen content, it was 0.59 mmol/g. In addition, SD-8022/DP-8020/RI-8020 manufactured by Tosoh Co., Ltd. was used, Gelpack GL-A150-S/GL-A160-S manufactured by Showa Denko Materials Co., Ltd. was used for the column, and As a result of GPC measurement using tetrahydrofuran as an eluent, the polystyrene-equivalent weight average molecular weight of the acrylic resin was 420,000.

(Production of transfer component A) To this acrylic resin solution (100 parts by mass in terms of solid content of acrylic resin), 1 part by mass of polyfunctional isocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd., CORONATE L, Solid content 75% by mass), 1 mass part of 1-hydroxycyclohexyl phenyl ketone (IGM Resins B.V., Irgacure 184) as a photopolymerization initiator, and further adding ethyl acetate to make the total solid content rate 27% by mass %, stir evenly for 10 minutes. Thereafter, the obtained solution was applied on a protective film, i.e., surface-release-treated polyethylene terephthalate (average thickness 25 μm) so that the average thickness of the adhesive layer during drying was 10 μm, and dried to form Adhesive layer. Furthermore, the adhesive layer was laminated on the base film (average thickness: 100 μm). Thereafter, aging was performed at 40° C. for 4 days. In this way, transfer member A is obtained.

The substrate film uses a three-layer resin film (Himilan 1706/ethylene and 1-hexene copolymer and butene and α-olefin copolymer/Himilan 1706, average thickness 100 μm), which is sequentially laminated with ionomer resin Himilan 1706 (Manufactured by Mitsui-DuPont Polymer Chemical Co., Ltd., ionomer resin), ethylene and 1-hexene copolymer, butene and α-olefin copolymer and Himilan 1706.

Furthermore, the adhesive layer, protective film, and base film were laminated by a roll laminator at 40° C., thereby making a configuration of protective film/adhesive layer/base film in this order. When using it as a transfer member, peel off the protective film and use it.

(Production of transfer components B~E) Transfer members B to E were produced by the same method except that the ratio of the adhesive layer components and the type of the base material were changed. Regarding the transfer member B, the ratio of the adhesive layer components was set to 100 parts by mass of acrylic resin, 4 parts by mass of CORONATE L, and 1 part by mass of Irgacure 184. Regarding the transfer member C, the ratio of the adhesive layer components was set to 100 parts by mass of acrylic resin, 0.2 parts by mass of CORONATE L, and 1 part by mass of Irgacure 184. With respect to the transfer member D, the ratio of the adhesive layer components was set to 100 parts by mass of acrylic resin, 1 part by mass of CORONATE L, and 1 part by mass of Irgacure 184. With respect to the transfer member E, the ratio of the adhesive layer components was set to 100 parts by mass of acrylic resin, 1 part by mass of CORONATE L, and 1 part by mass of Irgacure 184. For the transfer member D, the base film was changed to a silicon oxide film, and for the transfer member E, it was changed to a polyethylene terephthalate film.

The preparation method and various conditions of the evaluation sample are as follows.

The transfer member was stacked on a test vehicle (Test Vehicle, manufactured by NITRIDE SEMICONDUCTORS Co., Ltd.). The test vehicle was divided into individual devices, and the LED element was formed in a size of 3.1 through a buffer layer. mm × 3.6mm sapphire grain (sapphire die) on. The size of the transfer member was set to 200 mm×200 mm, and the average thickness was set to 110 μm. The size of the LED element was 25 μm×50 μm×6 μmt, and the size of the bump provided on the LED element was 15 μm×15 μm×2 μmt. The number of LED elements on the sapphire die is set to 4465. For lamination of the transfer member for sapphire crystal grains, a diaphragm-type vacuum lamination machine (lamination device V130, manufactured by Nikko-Materials Co., Ltd.) was used to obtain an attached body. Set it as a measurement sample. Lamination conditions were set at 40° C./0.5 MPa/10 seconds.

(Measurement of LLO transfer rate) A laser was irradiated from the sapphire crystal grain side of the prepared above sample. As the LLO device, DFL7560 (manufactured by DISCO Corporation) was used. The illuminance of the laser light was set to 1W. After irradiating the laser, the sapphire crystal grains are separated from the transfer member. The transfer rate of the LED element to the transfer member at the time of separation was measured. An LED element capable of being transferred to the transfer member without cracks and positional shift was regarded as a good sample. A case where the LED element remained on the side of the sapphire crystal grain, or a case where the LED element fell off from the transfer member or shifted from the transfer member when the sapphire crystal grain and the transfer member were separated was regarded as a defective sample, and the number thereof was counted. The evaluation amount is 6 sapphire crystal grains (4465 x 6 for LED elements), and the number of LED elements that can be transferred well is divided by the total number of LED elements (4465 x 6) and multiplied by 100, and then the The obtained value was calculated as the transfer rate, and this value was regarded as the LLO transfer rate. The case where the LLO transfer rate was 95% or more was rated as A, the case of 90% or more and less than 95% was rated as B, and the case of less than 90% was rated as C. As long as the rating is A or B, there is no question of practicality.

(Measurement of Transfer Rate to Carrier) Using a transfer member obtained by separating sapphire crystal grains in the measurement of LLO transfer rate as a sample, transfer of the LED element from the transfer member to the carrier was performed. After UV irradiation (UV exposure machine ML-320FSAT, manufactured by MIKASA Co., Ltd.) was applied to the transfer member, the transfer member was laminated on the carrier. As a carrier, a carrier constituted as Si crystal grain/adhesive layer is used. Si crystal grains were set to have a diameter of 20 mm and a thickness of 725 μmt. The component ratio of the adhesive layer was 100 parts by mass of acrylic resin, 7 parts by mass of CORONATE L, and 1 part by mass of Irgacure. And the average thickness of the adhesive layer was set to 10 μm and the adhesive force was set to 1 N/25 mm. The transfer member is separated from the carrier after lamination. UV irradiation conditions were set at 300 mJ/cm ² . For lamination, a diaphragm-type vacuum laminator (Laminator V130, manufactured by Nikko-Materials Co., Ltd.) was used. Lamination conditions were set at 40° C./0.5 MPa/30 seconds. An LED element capable of being transferred from the transfer member to the carrier without cracks and positional shift was regarded as a good sample. A case where the LED element remained on the transfer member, or a case where the LED element fell off from the carrier or shifted when the transfer member and the carrier were separated was regarded as a defective sample, and the number thereof was counted. Evaluate the transfer member on which 6 sapphire crystal grains (LED elements: 4465 x 6) of LED elements are transferred, and divide the number of LED elements that can be well transferred from the transfer member to the carrier by the total number of LED elements (4465 pieces x 6) and multiplied by 100, and the obtained value was calculated as the transfer rate, and this value was taken as the transfer rate to the carrier. The case where the transfer rate to the carrier was 95% or more was rated as A, the case of 90% or more and less than 95% was rated as B, and the case of less than 90% was rated as C. As long as the rating is A or B, there is no question of practicality.

(Measurement of Adhesive Force) The adhesive force of the transfer member before and after UV irradiation was measured by the following method. A sample before UV irradiation was obtained by attaching a transfer member to SUS (width 25 mm) with an average thickness of 0.5 mm using a laminator GK-13DX (manufactured by LAMI CORPORATION Inc.) at a lamination temperature of 40° C. . Using an ultraviolet exposure machine ("ML-320FSAT" manufactured by MIKASA Co., Ltd.), the sample was irradiated with ultraviolet light at an ultraviolet wavelength of 365 nm and an exposure amount of 300 mJ/cm ² to obtain a sample after UV irradiation. The peel strength was measured for each of the sample before UV irradiation and the sample after UV irradiation in accordance with the method of JIS C 5016:1994 (peel strength of conductor). Set Peel Strength to Adhesion.

(Measurement of tensile strength) The measurement of the tensile strength at 50° C. used a universal testing machine Autograph (AG-Xplus, manufactured by Shimadzu Corporation). A sample for evaluation with a width of 20 mm was cut out from the transfer member. Using this sample for evaluation, it measured on conditions of 25 mm of clip intervals, 5 mm/sec of tensile speed, and 50 degreeC. The value obtained when the sample for evaluation was stretched to 100% (twice the initial length) was defined as the tensile strength.

(evaluation of crystal expansion step) The transfer member obtained by separating the sapphire crystal grains during the measurement of the LLO transfer rate was installed on a 12-inch crystal expansion device (manufactured by Omiya Industry, MX-5145FN), with a lifting speed of 5 mm/s, a lifting amount of 100 mm, and a temperature (platform temperature) The condition of 50° C. is raised and lowered, and the transfer member is expanded. When the distance between the LED elements after the transfer member is pulled apart can be extended to more than 1 mm from the initial value (about 50 μm), the evaluation is A, and the following evaluation is B: when the self-expansion of the crystal is performed before the end of the 100 mm lift The case where the device is detached, the case where the transfer member cannot be extended due to excessive load and the device fails, or the case where the interval between the LED elements cannot be extended to 1 mm even when it is raised and lowered to 100 mm.

[Table 1] Example 1 Example 2 Example 3 Comparative example 1 Comparative example 2 transfer component A transfer component B transfer component C transfer component D transfer component E Adhesion before UV irradiation (N/25mm) 3 1.3 5 3 3 Adhesion after UV irradiation (N/25mm) 0.3 0.25 0.6 0.3 0.3 LLO transfer rate A A A A A Tensile strength (MPa) 7 7 7 0.5 over 20 Crystal Expansion Evaluation A A A B B Transfer rate to carrier A A B A A

It is evident from the evaluation results in Table 1 that the LED transfer member of the present invention is excellent in transfer rate and extensibility of Micro LED elements.

The entire content of the invention of Japanese Patent Application No. 2021-075245 for which it applied on April 27, 2021 is incorporated in this specification by reference. All documents, patent applications, and technical specifications described in this specification are incorporated by reference to the same extent as if each document, patent application, and technical specification were specifically and individually stated to be incorporated by reference. .

10, 20: transfer components 12: Substrate 14: Adhesive layer 30: Optical device substrate 32: Substrate for crystal growth 34: buffer layer 36: LED components 38: Bump 40: Attachment 50:laser light 52: pick up means 54: Construct the substrate 56: Gasket 60: carrier

FIG. 1 is a cross-sectional view of a transfer member 10 having a two-layer structure. FIG. 2 is a cross-sectional view of a single-layer transfer member 20 . FIG. 3 is a cross-sectional view of the optical device substrate 30 . Fig. 4 is a diagram for explaining a method of manufacturing an LED device. Fig. 5 is a diagram for explaining a method of manufacturing an LED device. Fig. 6 is a diagram for explaining a method of manufacturing an LED device. Fig. 7 is a diagram for explaining a method of manufacturing an LED device. Fig. 8 is a diagram for explaining a method of manufacturing an LED device. Fig. 9 is a diagram for explaining a method of manufacturing an LED device. Fig. 10 is a diagram for explaining a method of manufacturing an LED device. Fig. 11 is a diagram for explaining a method of manufacturing an LED device.

Domestic deposit information (please note in order of depositor, date, and number) none Overseas storage information (please note in order of storage country, institution, date, and number) none

10: Transfer components

12: Substrate

14: Adhesive layer

Claims (6)

An LED transfer member, which has a region where the adhesive force will be reduced by light irradiation on at least a part of the surface, and the tensile strength of the LED transfer member at 50° C. is 1 MPa˜10 MPa. The LED transfer member according to claim 1, wherein it has a substrate and an adhesive layer disposed on the substrate, and the adhesive layer is a region where the adhesive force is reduced by light irradiation. The LED transfer member according to Claim 1 or Claim 2, wherein the adhesive force of the region where the adhesive force is reduced is 0.7 N/25 mm or less after light irradiation. A method of manufacturing an LED device, using the LED transfer member described in any one of claim 1 to claim 3. A method of manufacturing an LED device, comprising the following steps: The surface of the LED transfer member according to any one of claims 1 to 3, which has a region where the adhesive force will be reduced, is brought into contact with the side of the optical device substrate on which the LED element is formed, so that the LED is transferred A member is attached to the optical device substrate to form an attached body. The optical device substrate has a substrate for crystal growth, a buffer layer formed on the substrate for crystal growth, and an LED element formed on the buffer layer. The buffer layer and The LED element is in a state divided into individual devices, irradiating laser light to the aforementioned buffer layer to destroy the aforementioned buffer layer, transferring the aforementioned LED element to the aforementioned LED transfer member by separating the aforementioned substrate for crystal growth from the aforementioned LED transfer member, Extending the aforementioned LED transfer member to expand the distance between the aforementioned LED elements that have been transferred to the aforementioned LED transfer member, The stretched LED transfer member is irradiated with light to reduce the adhesive force of the LED transfer member. The method of manufacturing an LED device according to claim 5, wherein the length of the long side of the LED element is 100 μm or less.

Images