Adhesive sheet and method for manufacturing electronic part or semiconductor device

Abstract

Provided is a novel method for improving productivity by making it easy to remove a processed element when manufacturing an electronic component or a semiconductor device. An object to be processed for manufacturing an electronic component or a semiconductor device is adhered to the concave-convex surface of the adhesive layer. And processing the object to be processed on the adhesive layer to obtain a processed object. And removing the processed result from the adhesive layer.

Description

Technical Field

[0001] The present invention relates to an adhesive sheet and a method for manufacturing an electronic component or a semiconductor device, for example, an adhesive sheet for capturing a semiconductor when transferring a semiconductor element by a laser lift-off method. Background Art

[0002] In most cases, the components used in electronic parts or semiconductor devices are formed in large quantities at one time to obtain multiple components. For example, a semiconductor chip is obtained by cutting a semiconductor wafer attached to an adhesive. When such a component is mounted on a semiconductor device, the component is often transferred. In particular, in order to transfer the component to a desired position, it is required to selectively transfer a specific component from a substrate before transfer to a substrate after transfer in a state where the substrate before transfer and the substrate after transfer are separated. For example, Patent Document 1 discloses a method for transferring a semiconductor chip by irradiating a semiconductor chip with a laser (laser lift-off method).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2021-141181 Summary of the invention

[0006] Problems to be solved by the invention

[0007] When the component moves from the substrate before transfer to the substrate after transfer, the component contacts the substrate after transfer, and the component is captured by the substrate after transfer. When transferring components between parallel substrates, if the component moves in a direction perpendicular to the surface direction of the two substrates, the position of the component in the substrate before transfer is consistent with the position of the component in the substrate after transfer when the two substrates are viewed from above. However, when performing such component transfer, it is found that there is a tendency for the position of the component in the substrate before transfer to be offset from the position of the component in the substrate after transfer. In recent years, miniaturization of semiconductor devices and components has been progressing, and this offset in the transfer position has the potential to hinder further miniaturization.

[0008] The object of the present invention is to improve the positioning accuracy of a transfer position when transferring a component.

[0009] Solutions for solving problems

[0010] The inventors of the present invention have conducted intensive research and have found that by providing projections and depressions on the surface of an adhesive sheet for capturing the element to be transferred, it is possible to suppress the element from shifting during capture, thereby solving the above-mentioned problem. The inventors of the present invention have completed the present invention after further repeating various studies.

[0011] That is, the present invention relates to the following [1] to [9].

[0012] [1] An adhesive sheet that captures a component that has moved away from a holding substrate and includes an adhesive layer having a surface with projections and depressions.

[0013] [2] The adhesive sheet according to [1], wherein the storage modulus of the adhesive layer is 0.001 MPa to 100 MPa.

[0014] [3] The adhesive sheet according to [1], wherein the adhesive layer has a plurality of convex portions on the surface that are separated from each other by concave portions.

[0015] [4] The adhesive sheet according to [1], wherein the adhesive layer has a plurality of convex portions separated from each other by boundaries defined by concave portions,

[0016] The pitch of the plurality of protrusions is greater than 1 µm and less than 100 µm.

[0017] [5] The adhesive sheet according to [1], wherein the adhesive layer has a plurality of convex portions separated from each other by boundaries defined by concave portions,

[0018] The area of ​​each of the plurality of protrusions is 10 μm 2 Above 2000µm 2 the following.

[0019] [6] The adhesive sheet according to [1], wherein the adhesive layer has convex portions whose boundaries are determined by concave portions,

[0020] A ratio of an area of ​​the protrusion to an area of ​​the adhesive layer is not less than 1% and not more than 95%.

[0021] [7] The adhesive sheet according to [1], wherein the adhesive layer is configured such that a ratio of an area of ​​the adhesive layer to one of the components is between 1% and 95% relative to an area of ​​the one of the components.

[0022] [8] The adhesive sheet according to [1], wherein the adhesive sheet captures the element separated from the holding substrate and away from the holding substrate by an external stimulus in the adhesive layer.

[0023] [9] A method for manufacturing an electronic component or a semiconductor device, the method comprising the following steps:

[0024] A step of separating a component adhered to a holding substrate from the holding substrate by external stimulation; and

[0025] A step of capturing the component separated from the holding substrate and away from the holding substrate in the adhesive sheet according to any one of [1] to [8].

[0026] Effects of the Invention

[0027] When transferring components, the positioning accuracy of the transfer position can be improved.

[0028] Other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings. It should be noted that in the accompanying drawings, the same or similar components are denoted by the same reference numerals. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention, and together with the description, serve to explain the principles of the present invention.

[0030] Figure 1 This is a schematic diagram of an adhesive sheet according to one embodiment.

[0031] Figure 2A This is a plan view showing an example of the concavities and convexities of the adhesive layer.

[0032] Figure 2B This is a plan view showing an example of the concavities and convexities of the adhesive layer.

[0033] Figure 2C This is a plan view showing an example of the concavities and convexities of the adhesive layer.

[0034] Figure 3A This is a cross-sectional view showing an example of the concavities and convexities of the adhesive layer.

[0035] Figure 3B This is a cross-sectional view showing an example of the concavities and convexities of the adhesive layer.

[0036] Figure 3C This is a cross-sectional view showing an example of the concavities and convexities of the adhesive layer.

[0037] Figure 4A This is a diagram for explaining separation and capture of components.

[0038] Figure 4B This is a diagram for explaining separation and capture of components.

[0039] Figure 5 This is a flowchart of a method for manufacturing an electronic component or a semiconductor device according to one embodiment. DETAILED DESCRIPTION

[0040] Hereinafter, the embodiments are described in detail with reference to the accompanying drawings. It should be noted that the following embodiments do not limit the technical solutions of the claims, and the combination of features described in the embodiments is not necessarily required for the invention. Two or more of the multiple features described in the embodiments can be combined arbitrarily. In addition, the same figure mark is marked for the same or identical structure, and repeated description is omitted.

[0041] (definition)

[0042] In this specification, the mass average molecular weight (Mw) and the number average molecular weight (Mn) are values ​​measured by size exclusion chromatography in terms of standard polystyrene, specifically values ​​measured in accordance with JIS K7252-1: 2016. In addition, in this specification, "(meth)acrylic acid" refers to both "acrylic acid" and "methacrylic acid".

[0043] In this specification, "electronic parts" include all parts used in electronic engineering and electrical engineering, and all parts constituting electronic equipment. "Electronic parts" can be formed by any one of semiconductors, conductors and / or insulators or by a combination of these. As "electronic parts", for example, active parts (mainly formed by semiconductors, such as transistors, IC (Integrated Circuit), LSI (Large Scale Integration), super LSI, diodes, light-emitting diodes, thyristors, three-terminal regulators, and camera elements, etc.), passive components (such as resistors, capacitors, speakers, coils, transformers, converters, relays, piezoelectric elements, crystal oscillators, ceramic resonators, and varistors, etc.), and structural parts (such as wiring parts, printed circuit boards, connectors, and switches, etc.). In addition, in this specification, "semiconductor devices" refer to all devices used in processors, memories, and sensors that can function by utilizing semiconductor characteristics. As examples of "semiconductor devices", micro-light-emitting diodes, sub-millimeter light-emitting diodes, power devices, MEMS (Micro Electro Mechanical Systems, micro-electromechanical systems), and control chips can be cited.

[0044] In this specification, when one or more lower limits and one or more upper limits of a numerical range (such as a range of content, etc.) are recorded, it can be understood that any lower limit and upper limit and combination thereof are recorded. For example, the description of preferably 1 or more, more preferably 2 or more, further preferably 3 or more and preferably 9 or less, more preferably 8 or less, and further preferably 7 or less indicates that the numerical range can be any of 1 or more and 9 or less, 1 or more and 8 or less, 1 or more and 7 or less, 2 or more and 9 or less, 2 or more and 8 or less, 2 or more and 7 or less, 3 or more and 9 or less, 3 or more and 8 or less, and 3 or more and 7 or less.

[0045] (Composition of adhesive sheet)

[0046] The adhesive sheet of one embodiment of the present invention includes an adhesive layer 120 having a concavoconvex surface. For example, the adhesive sheet may include a substrate 110 and an adhesive layer 120. Figure 1 However, the adhesive sheet does not necessarily have the base material 110. For example, the adhesive sheet may be composed of only the adhesive layer 120. In this case, an adhesive layer 120 with high support properties may be used.

[0047] (Base material)

[0048] The substrate 110 provided by the adhesive sheet functions as a support body for supporting the adhesive layer 120. The type of the substrate 110 is not particularly limited, and may be a hard substrate or a flexible substrate. From the perspective of improving the cushioning property when capturing the element, facilitating installation on other components, improving the peelability, facilitating lamination, or being able to be made into a roll form, the substrate 110 is preferably a flexible substrate. As the substrate 110, for example, a resin film can be used.

[0049] The resin film is a film using a resin material as a main material, and may be formed of the resin material or may contain additives in addition to the resin material. The resin film may also have laser transparency.

[0050] As specific examples of resin films, there can be cited: polyethylene films such as low-density polyethylene (LDPE) films, linear low-density polyethylene (LLDPE) films, and high-density polyethylene (HDPE) films, polypropylene films, polybutylene films, polybutadiene films, polymethylpentene films, ethylene-norbornene copolymer films, and polyolefin films such as norbornene resin films; ethylene-vinyl acetate copolymer films, ethylene-(meth)acrylic acid copolymer films, and ethylene-(meth)acrylic acid ester copolymer films. Ethylene copolymer films such as polyvinyl chloride films and vinyl chloride copolymer films; polyester films such as polyethylene terephthalate films and polybutylene terephthalate films; polyurethane films; polyimide films; polystyrene films; polycarbonate films; and fluororesin films. In addition, films containing a mixture of two or more materials, cross-linked films formed by cross-linking the resins forming these films, and modified films such as ionomer films can also be used. In addition, the substrate 110 can also be a laminated film formed by laminating two or more resin films.

[0051] From the viewpoint of versatility, relatively high strength and easy prevention of warping, and heat resistance, the resin film is preferably a single-layer film selected from the group consisting of polyethylene film, polyester film, and polypropylene film, or a laminated film formed by laminating two or more films selected from the group.

[0052] The thickness of the substrate 110 is not particularly limited, but is preferably in the range of 10 µm to 500 µm, more preferably 25 µm to 200 µm, and even more preferably 40 µm to 90 µm from the viewpoint of achieving both support and roll-winding properties.

[0053] (Adhesive layer)

[0054] The adhesive layer 120 is an adhesive layer and may contain a resin. As described above, the surface of the adhesive layer 120 has concavities and convexities. In addition, the adhesive sheet may have two or more adhesive layers 120. For example, the adhesive sheet may have a laminate of one or more adhesive layers 120.

[0055] (Composition of adhesive layer)

[0056] Examples of resins contained in the adhesive layer 120 include: polyisobutylene resins, polybutadiene resins, and rubber resins such as styrene-butadiene resins, acrylic resins, urethane resins, polyester resins, olefin resins, silicone resins, and polyvinyl ether resins. In addition, the adhesive layer may have heat resistance, and polyimide resins and silicone resins may be used as materials for such heat-resistant adhesive layers. The adhesive layer 120 may include a copolymer having two or more constituent units. The form of such a copolymer is not particularly limited, and may be any of a block copolymer, a random copolymer, an alternating copolymer, and a graft copolymer.

[0057] The resin contained in the adhesive layer 120 is preferably an adhesive resin that has adhesiveness alone. In addition, the resin is preferably a polymer having a mass average molecular weight (Mw) of 10,000 or more. From the viewpoint of improving adhesion, the mass average molecular weight (Mw) of the resin is preferably 10,000 or more, more preferably 70,000 or more, and further preferably 140,000 or more. In addition, from the viewpoint of suppressing the storage modulus below a specified value, the Mw is preferably 2 million or less, more preferably 1.2 million or less, and further preferably 900,000 or less. In addition, from the viewpoint of improving adhesion, the number average molecular weight (Mn) of the resin is preferably 10,000 or more, more preferably 50,000 or more, and further preferably 100,000 or more. In addition, from the viewpoint of suppressing the storage modulus below a specified value, the Mn is preferably 2 million or less, more preferably 1 million or less, and further preferably 700,000 or less. In addition, as described later, when the adhesive layer 120 includes a resin derived from an energy-reactive resin, its mass average molecular weight (Mw) and number average molecular weight (Mn) refer to the mass average molecular weight (Mw) and number average molecular weight (Mn) before the cross-linking reaction is performed by energy application. In addition, the glass transition temperature (Tg) of the resin is preferably -70°C or higher, more preferably -60°C or higher, and preferably -10°C or lower, more preferably -20°C or lower. By making Tg within this range, it is easy to make the adhesive force and storage modulus of the obtained adhesive within the range described later.

[0058] The amount of resin contained in the adhesive layer 120 relative to the total amount of components constituting the adhesive layer 120 can be appropriately set according to the required adhesion and storage modulus of the adhesive layer 120, and is preferably 30 mass % or more, more preferably 40 mass % or more, further preferably 50 mass % or more, further preferably 55 mass % or more, further preferably 60 mass % or more, and preferably 99.99 mass % or less, more preferably 99.95 mass % or less, further preferably 99.90 mass % or less, further preferably 99.80 mass % or less, and further preferably 99.50 mass % or less.

[0059] From the viewpoint of the morphological stability of the concavo-convex shape on the surface of the adhesive layer, the storage modulus of the adhesive layer 120 is preferably 0.001MPa or more, more preferably 0.01MPa or more, further preferably 0.03MPa or more, and further preferably 0.07MPa or more. On the other hand, from the viewpoint of suppressing the positional displacement when capturing the element, it is preferred that the storage modulus of the adhesive layer 120 is low. From this viewpoint, the storage modulus of the adhesive layer 120 is preferably 100MPa or less, more preferably 10MPa or less, further preferably 5MPa or less, further preferably 2MPa or less, further preferably 1MPa or less, further preferably 0.5MPa or less, further preferably 0.3MPa or less, further preferably 0.25MPa or less, and further preferably 0.2MPa or less. In this specification, the storage modulus is measured according to JIS K7244-1:1998. Specifically, the storage modulus of the adhesive layer 120 can be measured by preparing a cylindrical sample with a thickness of 3 mm and a diameter of 8 mm and measuring the storage modulus of the sample by a torsional shear method at 1 Hz and 23° C. using a viscoelasticity measuring device.

[0060] From the viewpoint of suppressing positional deviation when capturing the element, the adhesive force of the adhesive layer 120 is preferably 0.01N / 25mm or more, more preferably 0.1N / 25mm or more, further preferably 0.2N / 25mm or more, further preferably 0.3N / 25mm or more, further preferably 0.4N / 25mm or more, and from the viewpoint of peeling the captured element from the adhesive layer 120 without damage, it is preferably 100N / 25mm or less, more preferably 10N / 25mm or less, further preferably 1N / 25mm or less. In this specification, the adhesive force is measured in accordance with JIS Z0237:2009.

[0061] The resin contained in the adhesive layer 120 is preferably a thermoplastic resin. That is, the adhesive layer 120 is preferably thermoplastic. When a thermoplastic resin is used, the resin is softened by heating, and it is easy to form unevenness on the adhesive layer 120, and it is easy to maintain the uneven shape formed by cooling the resin. Examples of thermoplastic resins include rubber resins, acrylic resins, urethane resins, and olefin resins. As more preferred examples, polybutadiene thermoplastic elastomers using butadiene as a monomer, styrene thermoplastic elastomers (TPS) using styrene as a monomer, and acrylic thermoplastic elastomers using (meth)acrylate as a monomer can be exemplified.

[0062] In addition, the resin contained in the adhesive layer 120 is preferably derived from an energy-reactive resin. An energy-reactive resin refers to a resin whose elastic modulus is increased by imparting energy. As energy-reactive resins, energy-ray reactive resins and heat-reactive resins can be exemplified. An energy-ray reactive resin refers to a resin whose elastic modulus is increased by irradiating energy rays. In addition, a heat-reactive resin refers to a resin whose elastic modulus is increased by heating. The resin contained in the adhesive layer 120 is more preferably an energy-reactive resin derived from a thermoplastic, and further preferably an energy-ray reactive resin derived from a thermoplastic. The type of energy ray is not particularly limited, and for example, ultraviolet rays, electron beams, or ionizing radiation can be exemplified. The energy ray is preferably ultraviolet rays, that is, the resin is preferably an ultraviolet-reactive resin.

[0063] Thermoplastic energy-reactive resin refers to an energy-reactive resin that has thermoplasticity at least before energy is imparted. In addition, a resin derived from an energy-reactive resin means that the resin is obtained from an energy-reactive resin. For example, a resin derived from an energy-reactive resin is an energy-reactive resin after crosslinking.

[0064] When such an energy-reactive resin is used, the formed concavo-convex shape can be easily maintained by applying energy (for example, irradiating with energy rays) after the concavo-convex shape is formed on the resin.

[0065] As such an energy-reactive resin, a polymer having a polymerizable functional group introduced therein can be used. The polymerizable functional group is a functional group that undergoes crosslinking by the application of energy (e.g., irradiation with energy rays). Examples of the polymerizable functional group include alkenyl groups such as vinyl and allyl, (meth)acryloyl, oxetanyl, and epoxy groups.

[0066] For example, as the energy-reactive resin, a diene rubber composed of a polymer having a polymerizable functional group at the main chain end and / or side chain can be used. Diene rubber refers to a rubber-like polymer having a double bond in the polymer main chain. As a specific example of the diene rubber, a polymer using butadiene or isoprene as a monomer (i.e., having a butene diyl group or a pentene diyl group as a constituent unit) can be exemplified. As the energy-reactive resin, polybutadiene resin (PB resin), styrene-butadiene-styrene block copolymer (SBS resin), and styrene-isoprene-styrene block copolymer (SIS resin) are preferred. These resins can be used as ultraviolet-reactive resins.

[0067] From the viewpoint of facilitating the maintenance of the concavo-convex shape of the adhesive layer, the average value of the number of polymerizable functional groups per molecule in these energy-reactive resins is preferably 1.5 or more, more preferably 2 or more. On the other hand, from the viewpoint of improving the adhesion and flexibility of the adhesive layer, the average value is preferably 20 or less, more preferably 15 or less, and further preferably 10 or less.

[0068] The adhesive layer 120 may contain one resin or two or more resins. In one embodiment, the adhesive layer 120 contains a liquid resin or a resin derived from an energy-reactive liquid resin in addition to a thermoplastic resin or a thermoplastic energy-reactive resin. Liquid resin refers to a resin that is a liquid at room temperature (25° C.) before mixing. In addition, energy-reactive liquid resin refers to an energy-reactive resin that is a liquid at room temperature (25° C.) before mixing and before energy is applied. By adding a liquid resin as described above, it is easy to control the adhesion and storage modulus of the adhesive layer 120.

[0069] In order to easily maintain the concavo-convex shape of the adhesive layer, it is preferred that the adhesive layer 120 of one embodiment contains a resin derived from an energy-reactive liquid resin. Examples of such liquid resins include diene rubbers, and as a specific example, polybutadiene resins using butadiene as a monomer.

[0070] The adhesive layer 120 of one embodiment includes a combination of a resin derived from a thermoplastic energy-reactive resin and a resin derived from an energy-reactive liquid resin. Preferably, the adhesive layer 120 includes a combination of a resin derived from an energy-ray-reactive styrene-based thermoplastic elastomer and a resin derived from a diene rubber as an energy-ray-reactive liquid resin.

[0071] As a preferred example of a thermoplastic energy-ray reactive resin, a resin using styrene and butadiene as monomers can be cited, and as a particularly preferred example, an SBS resin can be cited. In addition, the resin using styrene and butadiene as monomers includes a resin using only styrene and butadiene as monomers, and also includes a resin using monomers other than styrene and butadiene. From the perspective of improving the adhesion of the adhesive layer 120, the mass average molecular weight (Mw) of this resin is preferably 10,000 or more, more preferably 50,000 or more, more preferably 100,000 or more, and more preferably 150,000 or more. In addition, from the perspective of reducing the storage modulus of the adhesive layer 120 to an appropriate range, the mass average molecular weight (Mw) of this resin is preferably 2 million or less, more preferably 1 million or less, and more preferably 200,000 or less. For the same reason, the number average molecular weight (Mn) of this resin is preferably 10,000 or more, more preferably 30,000 or more, more preferably 70,000 or more, and more preferably 130,000 or more. On the other hand, it is preferably 2 million or less, more preferably 1 million or less, and more preferably 200,000 or less.

[0072] As a preferred example of the energy-ray reactive liquid resin, a resin using butadiene as a monomer can be cited, and as a particularly preferred example, a PB resin can be cited. It should be noted that the resin using butadiene as a monomer includes not only a resin using butadiene as a monomer, but also a resin using a monomer other than butadiene. From the perspective of increasing the storage modulus of the adhesive layer 120, the mass average molecular weight (Mw) of this resin is preferably 500 or more, more preferably 1000 or more, further preferably 2000 or more, and further preferably 3000 or more. In addition, from the perspective of reducing the storage modulus of the adhesive layer 120, the mass average molecular weight (Mw) of this resin is preferably 500,000 or less, more preferably 100,000 or less, and further preferably 10,000 or less. For the same reason, the number average molecular weight (Mn) of this resin is preferably 500 or more, more preferably 1000 or more, further preferably 3000 or more, and further preferably 120,000 or more. On the other hand, it is preferably 500,000 or less, more preferably 100,000 or less, and further preferably 10,000 or less.

[0073] The ratio of the resin derived from the thermoplastic energy-responsive resin to the resin derived from the energy-responsive liquid resin contained in the adhesive layer 120 can be selected according to the required adhesive force and storage modulus of the adhesive layer 120. For example, from the viewpoint of improving the adhesive force, the amount of the resin derived from the energy-responsive liquid resin can be 10 parts by mass or more, 30 parts by mass or more, and further can be 40 parts by mass or more, with respect to 100 parts by mass of the resin derived from the thermoplastic energy-responsive resin. On the other hand, from the viewpoint of improving the storage modulus, it can be 500 parts by mass or less, 200 parts by mass or less, and further can be 150 parts by mass or less.

[0074] In addition, the ratio of the total amount of the resin derived from the thermoplastic energy-responsive resin and the resin derived from the energy-responsive liquid resin to the total amount of the components constituting the adhesive layer 120 can be selected according to the required adhesive force and storage modulus of the adhesive layer 120. For example, the ratio is preferably 30% by mass or more, more preferably 40% by mass or more, further preferably 50% by mass or more, further preferably 55% by mass or more, further preferably 60% by mass or more, and preferably 99.99% by mass or less, more preferably 99.95% by mass or less, further preferably 99.90% by mass or less, further preferably 99.80% by mass or less, further preferably 99.50% by mass or less.

[0075] The adhesive layer 120 may contain components other than the resin. For example, the adhesive layer 120 may contain one or more of a tackifier, a polymerization initiator, a UV (ultraviolet) absorber, and other additives.

[0076] The polymerization initiator is a component that starts a crosslinking reaction by applying energy (eg, irradiation with energy rays). When the adhesive layer 120 includes an energy-reactive resin, the adhesive layer 120 further includes a polymerization initiator, so that the crosslinking reaction proceeds even when a relatively low energy is applied.

[0077] As the polymerization initiator, for example, a photopolymerization initiator can be used. Examples of the photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzyl phenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, bibenzyl, biacetyl, and 8-chloroanthraquinone.

[0078] The adhesive layer 120 may include one polymerization initiator or two or more polymerization initiators. When the adhesive layer 120 includes a polymerization initiator, the content of the polymerization initiator in the adhesive layer 120 is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, further preferably 1% by mass or more, and preferably 10% by mass or less, more preferably 5% by mass or less, and further preferably 2% by mass or less from the viewpoint of allowing the crosslinking reaction to proceed at an appropriate speed.

[0079] Examples of the UV absorber include benzotriazole compounds, oxazolic acidamide compounds, and benzophenone compounds.

[0080] There is no particular limitation on other additives that the adhesive layer 120 may contain, and examples thereof include: light stabilizers such as hindered amine, benzophenone, or benzotriazole; antioxidants such as phenolic, aromatic amine, sulfur, or phosphorus such as phosphate compounds; resin stabilizers such as imidazole resin stabilizers, dithiocarbamate resin stabilizers, phosphorus resin stabilizers, or thioester resin stabilizers; fillers; pigments; extenders; and softeners, etc.

[0081] When the adhesive layer 120 contains these additives, the content of the additives in the adhesive layer 120 is preferably 0.0001 mass % or more, more preferably 0.01 mass % or more, particularly preferably 0.1 mass % or more, further preferably 1 mass % or more, and preferably 20 mass % or less, more preferably 10 mass % or less, further preferably 5 mass % or less.

[0082] (Shape of adhesive layer)

[0083] The surface of the adhesive layer 120 has projections and depressions. As described later, the adhesive sheet can capture the element separated from the holding substrate in the adhesive layer 120. Specifically, the adhesive sheet can capture the element in the projections of the adhesive layer 120. On the other hand, by bringing the element close to the adhesive layer 120, the gas compressed between the element and the adhesive layer 120 can escape to the recesses of the adhesive sheet. In this way, by having projections and depressions on the adhesive layer 120, the pressure generated between the element and the adhesive layer 120 can be alleviated. Therefore, it is also possible to suppress the displacement of the holding position of the element on the adhesive sheet due to the pressure generated between the element and the adhesive layer 120.

[0084] As described above, as long as the surface of the adhesive layer 120 has recesses, the pressure generated between the device and the adhesive layer 120 can be relieved. Therefore, the specific shape of the recesses and projections on the surface of the adhesive layer 120 is not limited.

[0085] For example, in one embodiment, the adhesive layer 120 has a plurality of convex portions separated from each other via concave portions on the surface. Each of the plurality of convex portions can be separated by a concave portion that is continuous across the entirety of the adhesive layer 120. By providing a continuous concave portion around such a convex portion, the pressure relief effect can be improved. In addition, in one embodiment, the concave portion located around each of the plurality of convex portions is continuous to the end of the adhesive layer 120. In this way, by providing a concave portion that is continuous to the end of the adhesive layer 120, the air compressed between the element and the convex portion of the adhesive layer 120 can be efficiently released to the outside of the element. FIG. 2A to FIG. 2C 1 is a plan view showing the shape of such an adhesive layer 120 .

[0086] like Figure 2A As shown in FIG. 1 , the surface of the adhesive layer 120 may have protrusions arranged regularly. Regular arrangement of protrusions means that the protrusions are arranged on a straight line at fixed intervals. Figure 2B As shown, the protrusions may also be arranged in a manner with regularly varying intervals. Figure 2B In the example of , the intervals between the convex parts in the center of the adhesive sheet are shortened, and the intervals between the convex parts in the peripheral part of the adhesive sheet are lengthened. According to this structure, the holding force of the adhesive sheet can be improved, and the compressed air can be efficiently released from the peripheral part of the element through the wider concave part. Moreover, the convex parts can also be arranged irregularly.

[0087] Figure 2C is a top view showing other shapes of the adhesive layer 120. Figure 2C As shown, stripe-shaped protrusions may be provided on the surface of the adhesive layer 120 . Figure 2C In the embodiment, linear protrusions with a fixed width are arranged at fixed intervals. Figure 2B Likewise, the width or interval of the linear protrusions may be varied regularly, or the linear protrusions may be arranged irregularly.

[0088] From the viewpoint of improving the pressure relief effect, the spacing between the protrusions is preferably greater than 1µm, more preferably greater than 5µm, further preferably greater than 10µm, and further preferably greater than 15µm. On the other hand, from the viewpoint of increasing the contact area between the adhesive layer 120 and the element to suppress positional deviation during capture, the spacing is preferably less than 100µm, more preferably less than 75µm, further preferably less than 50µm, further preferably less than 35µm, and further preferably less than 25µm. Here, the spacing between the protrusions refers to the smallest spacing among all the protrusion spacings in the adhesive layer 120 as a whole. For example, Figure 2A In the case of, the pitch of the convex portions means the spacing between the convex portions on the straight line where the convex portions are arranged at a fixed interval. When the convex portions are arranged on a plurality of straight lines, the pitch means the spacing between the convex portions on the straight line where the convex portions are arranged at the shortest interval. In addition, Figure 2C In the case of, the pitch of the convex portions means the interval between the linear convex portions. In this specification, the interval between the convex portions means the interval between the centers of the convex portions.

[0089] In addition, if Figure 2B As shown, the minimum interval among all the convex intervals in the central part of the adhesive sheet can be shorter than the minimum interval among all the convex intervals in the peripheral part of the adhesive sheet. Here, the central part is, for example, a circular area having 1 / 4 of the area of ​​the adhesive sheet and centered on the center of gravity of the adhesive sheet, and the peripheral part is, for example, all areas outside the central part of the adhesive sheet.

[0090] The specific shape of the convex portion is not particularly limited. For example, the convex portion may also have a pillar shape. As a specific example, the convex portion may have a cylindrical shape or a prism shape. In addition, as described above, the convex portion may extend in a linear shape or in a curved shape such as a wave shape. In addition, these convex portions may be provided with a slope.

[0091] Figure 3A FIG. 1 is a cross-sectional view of the adhesive layer 120 according to one embodiment, which passes through the protrusion and is perpendicular to the surface of the adhesive layer 120 . Figure 3A The convex portion shown is provided with an inclination, that is, the front end of the convex portion becomes thinner. Figure 3A As shown, the front end of the convex portion can be a curved surface. According to this structure, the impact when the element separated from the holding substrate contacts the adhesive layer 120 is further alleviated, so that the adhesive layer 120 can easily hold the element without displacement. On the other hand, the front end of the convex portion can also be a flat surface.

[0092] like Figure 3A As shown, the surface of the adhesive layer 120 may have flat concave portions and convex portions protruding from the concave portions. As described above, the adhesive layer 120 may have a plurality of convex portions spaced apart from each other with their boundaries determined by the concave portions.

[0093] As another example, the protrusion may be Figure 3B The convex portion may be a hemisphere or a part of a sphere. Figure 3C As shown, it is in the shape of a letter T. As another example, the convex portion can be in the shape of a plurality of particle collections, mushroom-shaped, lotus leaf-shaped, or needle-shaped. As yet another example, the surface of the adhesive layer 120 can be rough or fibrous, and such a surface can also be said to have concave-convex.

[0094] From the viewpoint of improving adhesion to suppress positional deviation during capture, the width or diameter of each convex portion is preferably 1µm or more, more preferably 2µm or more, further preferably 5µm or more, further preferably 10µm or more. On the other hand, from the viewpoint of improving the pressure relief effect, the width or diameter of each convex portion is preferably 100µm or less, more preferably 50µm or less, further preferably 30µm or less, further preferably 20µm or less. Here, the width and diameter of a convex portion respectively represent the minimum distance and maximum distance between two parallel lines contacting from both sides of the convex portion on the surface of the concave portion ( Figure 3A Indicated by B in the figure).

[0095] In addition, from the viewpoint of improving adhesion and suppressing positional deviation during capture, the area of ​​each convex portion is preferably 10 μm 2 More than 20µm is more preferred 2 More preferably, 30 μm 2 On the other hand, from the perspective of improving the pressure relief effect, the area of ​​each convex portion is preferably 2000 μm 2 Below, more preferably 1000µm 2 Below, more preferably 500µm 2 Here, the area of ​​the convex portion refers to the area of ​​the portion protruding from the surface of the concave portion ( Figure 3A In this case, it is the area of ​​a circle with diameter B).

[0096] In addition, from the viewpoint of improving impact absorption to suppress positional deviation during capture, the height of each convex portion is preferably 1 µm or more, more preferably 3 µm or more, and further preferably 5 µm or more. On the other hand, from the viewpoint of improving morphological stability, the height of each convex portion is preferably 20 µm or less, more preferably 15 µm or less, and further preferably 10 µm or less. Here, the height of the convex portion is Figure 3A Indicated by H.

[0097] In addition, from the perspective of improving adhesion to suppress positional deviation during capture, the area occupied by the plurality of convex portions relative to the area of ​​the adhesive layer 120 is preferably 1% or more, more preferably 5% or more, further preferably 10% or more, further preferably 18% or more, further preferably 40% or more. On the other hand, from the perspective of improving the pressure relief effect, the area of ​​each convex portion is preferably 95% or less, more preferably 75% or less, further preferably 60% or less.

[0098] The concavoconvexity of the adhesive layer 120 can also be designed according to the shape of the element captured by the adhesive sheet. For example, from the perspective of improving adhesion to suppress positional deviation during capture, the ratio of the bonding area of ​​the adhesive layer 120 to an element relative to the area of ​​an element is preferably 1% or more, more preferably 2% or more, more preferably 3% or more, more preferably 4% or more, more preferably 5% or more, more preferably 7% or more, and more preferably 10% or more. On the other hand, from the perspective of improving the pressure relief effect, the area of ​​each convex portion is preferably 95% or less, more preferably 70% or less, more preferably 50% or less, and more preferably 30% or less. Figure 3A In the case of, the bonding area is equivalent to the area of ​​a circle with a diameter T. It should be noted that when the capture position of the element on the adhesive sheet is offset, the bonding area may change. At this time, it is preferred that the ratio of the bonding area is within the above range regardless of the capture position of the element.

[0099] (Other layers)

[0100] The adhesive sheet may also have a layer other than the substrate 110 and the adhesive layer 120. For example, an adhesive layer may be further provided on the surface of the substrate 110 opposite to the adhesive layer 120. The adhesive sheet can be attached to other substrates such as quartz glass via such an adhesive layer. The type of the further provided adhesive layer is not particularly limited, and for example, the further provided adhesive layer may be formed using a common adhesive.

[0101] (Method for producing adhesive sheet)

[0102] There is no particular limitation on the method for manufacturing the adhesive sheet. For example, an adhesive sheet having an adhesive layer 120 on a substrate 110 can be made as follows. First, an organic solvent is added to a raw material composition containing the components of the adhesive layer 120 to prepare a solution of the raw material composition. Next, the solution is applied to the substrate to form a coating film and then dried, thereby providing an adhesive layer on the substrate 110. Furthermore, by performing a process of providing a concavo-convex surface on the adhesive layer, an adhesive layer 120 having a concavo-convex surface can be formed.

[0103] As examples of organic solvents for preparing the solution of the raw material composition, toluene, ethyl acetate and methyl ethyl ketone can be exemplified. The solid content concentration of the solution of the raw material composition is preferably 10% by mass or more, more preferably 25% by mass or more, further preferably 45% by mass or more, and preferably 80% by mass or less, more preferably 70% by mass or less, and further preferably 65% ​​by mass or less. As a coating method for the solution, for example, spin coating, spray coating, rod coating, knife coating, roll coating, roll knife coating, scraping, die coating, gravure coating, and printing (such as screen printing and inkjet) can be exemplified.

[0104] There is no particular restriction on the processing of setting concavoconvex on the surface of the adhesive layer. For example, concavoconvex can be set on the surface of the adhesive layer using an embossing method. In the embossing method, a mold having a shape complementary to the concavoconvex to be set can be used on the surface. Specifically, the concavoconvex can be set on the surface of the adhesive layer by heating the adhesive layer while pressing the adhesive layer on the substrate using a mold. As a more specific method, the adhesive layer can be pressed by a mold, the adhesive layer is heated and maintained for a specified time, and then the adhesive layer is cooled and the mold is removed. When the adhesive layer is heated, for example, the adhesive layer can be heated to a temperature higher than the softening point of the adhesive layer. In addition, the time for maintaining the adhesive layer in a heated state is also not particularly limited, for example, it can be maintained for more than 10 seconds, or it can be maintained for less than 10 minutes. As a specific method for heating the adhesive layer while pressing the adhesive layer using a mold, a method in which the adhesive layer on the substrate and the mold are vacuum laminated can be exemplified. It should be noted that, instead of performing the two-step process of forming the adhesive layer and forming the irregularities, the adhesive layer 120 having the irregularities on the surface may be formed on the substrate in a one-step process.

[0105] As another method, the adhesive layer 120 having a concavo-convex shape can be provided by spraying a solution of the raw material composition. In addition, a filler can be added to the solution of the raw material composition, and the adhesive layer 120 having a rough surface or a fibrous surface can be provided by coating the solution. As another method, the adhesive layer having a concavo-convex shape can be provided directly on the substrate by applying the solution of the raw material composition in a desired pattern using a printing method such as an inkjet method.

[0106] In addition, the adhesive sheet without substrate 110 can be made by forming the composition of each component of the adhesive layer into a sheet. Moreover, the adhesive layer can also be formed by applying the liquid adhesive of each component of the adhesive layer to any object. In these cases, the surface of the adhesive layer can be treated with unevenness after the adhesive layer is formed, and the adhesive layer can also be formed by forming unevenness on the surface.

[0107] (Method for manufacturing electronic parts or semiconductor devices using adhesive sheets)

[0108] The adhesive sheet of one embodiment of the present invention as described above can be used to capture an element away from a holding substrate. For example, the adhesive sheet can be used as a grain capture sheet for capturing grains such as semiconductor grains. The element is used to manufacture electronic parts or semiconductor devices. That is, the adhesive sheet can be appropriately used in the manufacture of electronic parts or semiconductor devices.

[0109] A method for manufacturing an electronic component or semiconductor device according to one embodiment of the present invention includes a step of separating a component from a holding substrate and a step of capturing the component on an adhesive sheet. In this way, the electronic component or semiconductor device can be manufactured by further processing the component captured on the adhesive sheet. Figure 5 The flowchart is explained in detail.

[0110] (S10: Preparation of holding substrate)

[0111] In step S10, a holding substrate with components attached thereto is prepared. The type of components is not particularly limited. The components may be, for example, semiconductor chips such as LED chips, semiconductor chips with protective films, semiconductor chips with adhesive film (DAF), etc. In addition, the components may be micro-LEDs, sub-millimeter light-emitting diodes, power devices, MEMS (Micro ElectroMechanical Systems), or control chips, or their constituent elements. In addition, the components may be monolithic objects such as wafers, panels, or substrates. For example, the components may also have a circuit surface, which is formed with an integrated circuit having circuit elements such as transistors, resistors, and capacitors. In addition, the components are not necessarily limited to monolithic objects, but may also be various wafers or various substrates that are not monolithic.

[0112] The size of the element is not particularly limited. For example, the size of the element can be 100 μm. 2 Above, 500µm 2 Above, or 1000µm 2 On the other hand, the size of the element can be 100mm 2 Below, 25mm 2 Below, or 1mm 2 When using small-sized components, the laser lift-off method described below is suitable for attaching the components because it is easy to selectively separate the small components.

[0113] As wafers, for example, semiconductor wafers such as silicon wafers, silicon carbide (SiC) wafers, compound semiconductor wafers (such as gallium phosphide (GaP) wafers, gallium arsenide (GaAs) wafers, indium phosphide (InP) wafers, and gallium nitride (GaN) wafers) can be cited. The size of the wafer is not particularly limited, and can be 8 inches (200 mm in diameter) or more, preferably 12 inches (300 mm in diameter) or more. It should be noted that the shape of the wafer is not limited to a circle, and can be a square or a rectangle, for example.

[0114] As the panel, a fan-out semiconductor package (such as FOWLP or FOPLP) can be exemplified. That is, the processed object can be a semiconductor package before or after singulation in the fan-out semiconductor package manufacturing technology. The size of the panel is not particularly limited, and can be, for example, a square substrate of about 300 mm to 700 mm.

[0115] Examples of the substrate include a glass substrate, a sapphire substrate, and a compound semiconductor substrate.

[0116] The type of the holding substrate is not particularly limited. For example, the holding substrate may be an adhesive sheet or a tray. The adhesive sheet may have an adhesive layer, and the adhesive layer may be provided on the substrate. In this case, the holding substrate may hold the component on the adhesive layer. The substrate may be a resin film or a hard substrate.

[0117] The method for preparing the holding substrate for holding the element is also not particularly limited. For example, a semiconductor wafer may be attached to the holding substrate, and then the semiconductor wafer may be cut. By cutting the semiconductor wafer, the element may be obtained, and thus the holding substrate with the element attached thereto may be obtained.

[0118] As another method, the element obtained by cutting the semiconductor wafer can be transferred to the holding substrate, thereby obtaining the holding substrate with the element attached thereto. For example, after cutting the semiconductor wafer held on the wafer substrate, the obtained element can be brought into close contact with the adhesive layer of the holding substrate. Then, by applying an external stimulus such as a laser, the adhesion between the wafer substrate and the element can be reduced. Through this process, the element can be transferred from the wafer substrate to the holding substrate.

[0119] It should be noted that, as described later, in one embodiment, the element is separated from the holding substrate by irradiation with laser (laser lift-off method). When this method is used, the adhesive layer of the holding substrate preferably contains a laser absorbent. As the laser absorbent, for example, one or more selected from pigments and dyes can be exemplified.

[0120] (S20: Separation of components)

[0121] In step S20, the component attached to the holding substrate is separated from the holding substrate by external stimulation. The type of external stimulation is not particularly limited, and examples thereof include energy application, cooling, extension of the holding substrate, and physical stimulation (for example, using a pin to push the back of the holding substrate). By using one or more of these external stimuli, the bonding force between the holding substrate and the component can be reduced, and then the component can be separated from the holding substrate.

[0122] In this embodiment, the component capture in step S30 can be performed in a manner that the relative arrangement of the plurality of components on the holding substrate is different from the relative arrangement of the plurality of components on the adhesive sheet. For this purpose, in step S20, it is preferred to selectively separate a portion of the plurality of components attached to the holding substrate. Therefore, in step S20, an external stimulus can be selectively applied to a portion of the plurality of components attached to the holding substrate or to the attachment portion of the component in the holding substrate.

[0123] As methods of imparting energy, local heating, light irradiation, or heat ray irradiation can be exemplified. In addition, as methods of light irradiation, infrared irradiation, visible light irradiation, and laser irradiation can be exemplified. It is preferred to perform laser irradiation as an external stimulus, that is, to separate the component from the holding substrate using a laser stripping method. At this time, the laser is irradiated toward the pasting portion of the specific component in the holding substrate. For example, such laser irradiation can be performed from the surface of the holding substrate that is opposite to the component. As a result, gas is generated at the contact portion between the specific component and the holding substrate. For example, if the laser is absorbed by the adhesive layer, gas is generated by sublimation of at least a portion of the adhesive layer. As described above, by sublimation of at least a portion of the adhesive layer, the bonding area between the specific component and the adhesive layer is reduced, and therefore the bonding force between the specific component and the holding substrate is reduced. In addition, the pressure of the generated gas also reduces the bonding force between the specific component and the holding substrate. As a result, the specific component is separated from the holding substrate.

[0124] The irradiation conditions of the laser are not particularly limited. From the perspective of selectively separating a portion of the elements efficiently, the frequency of the laser is preferably 10,000 Hz or more and 100,000 Hz or less. In addition, the beam diameter of the laser is preferably 10 μm or more, more preferably 20 μm or more, on the other hand, preferably 100 μm or less, more preferably 40 μm or less. The output of the laser is preferably 0.1 W or more and 10 W or less. The scanning speed of the laser is preferably 50 mm / sec or more and 2000 mm / sec or less.

[0125] (S30: Capturing of components)

[0126] In step S30, the component separated from the holding substrate is captured on the adhesive sheet. Specifically, the component is relatively far away from the holding substrate. In addition, the component is relatively close to the adhesive sheet. Then, the component is captured on the adhesive sheet by contacting the adhesive layer of the adhesive sheet.

[0127] like Figure 4A As shown in FIG. 1 , the separated component 420 is captured at the position A on the adhesive sheet 450 by positioning the position A on the adhesive sheet 450 so as to face the component 420 attached to the holding substrate 410. Figure 4B As shown, by positioning position B on the adhesive sheet 450 in a manner opposite to the component 430 adhered to the holding substrate 410, the separated component 430 is captured at position B on the adhesive sheet 450. As described above, the components can be separated and captured while changing the relative position of the holding substrate and the adhesive sheet in the surface direction. As described above, the components can be positioned in a manner that the relative configuration of the plurality of components on the holding substrate is different from the relative configuration of the plurality of components on the adhesive sheet. However, when an adhesive sheet having a flat surface is used as described above, the pressure generated between the component and the adhesive sheet may cause the components to be stuck to the adhesive sheet. Figure 4A In the example of , the component 420 may be captured at a position offset from position A. However, since the surface of the adhesive layer has projections and depressions, the pressure generated between the component and the adhesive layer is relieved, so it is easier to capture the component at a desired position of the adhesive sheet.

[0128] In one embodiment, the holding substrate and the adhesive sheet are stationary, and the element separated from the holding substrate moves toward the adhesive sheet. For example, when using the laser stripping method, the pressure of the gas generated by the irradiation of the laser can move the element toward the adhesive sheet. On the other hand, the element does not necessarily have to move. For example, the holding substrate can be moved away from the element. In addition, the adhesive sheet can also be moved toward the element.

[0129] (S40: Component Processing)

[0130] In step S40, electronic parts or semiconductor devices are manufactured using the components captured on the adhesive sheet. For example, the components captured on the adhesive sheet can be transferred to a wiring substrate. Wiring connected to the components can also be provided on the wiring substrate. At this time, the positions of the components on the wiring substrate have been predetermined. Therefore, in step S30, the adhesive sheet can be used to capture multiple components in a configuration consistent with the relative configuration between multiple components on the wiring substrate. Then, the wiring substrate is joined to the surfaces of the multiple components on the opposite side of the adhesive sheet. Then, the adhesive sheet is peeled off from the multiple components. In this order, multiple components can be mounted on the wiring substrate. In this way, electronic parts or semiconductor devices having components (such as semiconductor components) can be manufactured.

[0131] As another example, the adhesive sheet with the captured element may be attached to a substrate or other element. Furthermore, by performing wiring and other operations using an appropriate method, an electronic component or semiconductor device having an element (e.g., a semiconductor element) on a substrate, and an electronic component or semiconductor device having stacked elements can be manufactured. When the adhesive sheet is used for such a purpose, the adhesive sheet preferably has an adhesive layer on the surface opposite to the adhesive layer provided on the substrate in addition to the substrate and the adhesive layer.

[0132] Example

[0133] The following compounds were used in Examples and Comparative Examples.

[0134] Styrene block copolymer (A): 1,2-vinyl-containing styrene block copolymer SBS (content of styrene block: 20% by mass, content of butadiene block: 80% by mass, content of diblock: 13% by mass, content of constituent units having 1,2-vinyl as side chains in all constituent units constituting the butadiene block: 42 mol%, number average molecular weight (Mn): 160,000, mass average molecular weight (Mw): 180,000, Tg: -40°C)

[0135] Liquid butadiene resin (B) having a reactive functional group: Liquid butadiene rubber (Mw: 5500, Tg: -49°C)

[0136] · Photopolymerization initiator (C): acylphosphine oxide type photopolymerization initiator (manufactured by IGM Resins, Omnirad819)

[0137] (Example 1)

[0138] An adhesive composition was prepared by dissolving 100 parts by mass of a styrene block copolymer (A), 3 parts by mass of a photopolymerization initiator (C), and 3 parts by mass of an antioxidant (Irganox 1010 manufactured by BASF / Irgafos 168 manufactured by BASF = 1 / 1) in toluene. The adhesive composition was applied to the release-treated surface of a release sheet (manufactured by Lintec Co., Ltd., trade name: SP-PET381130), and the obtained coating was dried at 100°C for 2 minutes to form an adhesive layer with a thickness of 25 µm. The adhesive sheet was prepared by laminating the easy-bonding surface of a PET film substrate (manufactured by Toyobo Co., Ltd., thickness 50 µm, trade name: PET50A4160) on the adhesive layer.

[0139] After the release sheet was peeled off, the adhesive layer of the adhesive sheet was attached to the stamp mold with a concave shape formed in advance, and vacuum laminated at 100°C and 0.5 MPa for 300 seconds. Then, a UV irradiator (manufactured by Heraeus) was used at an illumination of 200 mW / cm 2 , Light intensity: 800mJ / cm 2 The adhesive sheet having a concavo-convex shape on the surface was prepared by irradiating with ultraviolet rays. The storage modulus of the adhesive layer at 23° C. was 1.0 MPa, and the adhesive force was 0.13 N / 25 mm.

[0140] The concavo-convex shape of the adhesive layer of the adhesive sheet Figure 2A Similarly, the shape of the columns with inclination is arranged in a grid shape. Each column functions as an adhesive island. In Example 1, a plurality of adhesive sheets with different pitches of protrusions are prepared. The pitch (P) between the columns in each adhesive sheet is 20µm, 30µm or 40µm. In addition, Figure 3A The height (H) of each column shown is 7 µm, the diameter (T) of the tip is 8 µm, and the diameter (B) of the base is 16 µm. In Example 1, other Examples, and Comparative Examples, a stamp mold having a surface shape complementary to this concavo-convex shape is used to form the concavo-convex shape on the adhesive sheet.

[0141] It should be noted that the ratio of the area of ​​the bonding portion of the adhesive layer and the element to be captured (i.e., the area of ​​the front end surface of the protrusion) to the area of ​​the adhesive sheet when the pitch is 20µm, 30µm, and 40µm, respectively, is approximately 12.6%, 5.9%, and 3.1%.

[0142] (Example 2)

[0143] An adhesive composition was prepared by dissolving 100 parts by mass of a styrene block copolymer (A), 33.5 parts by mass of a liquid butadiene resin (B) having a reactive functional group, 3 parts by mass of a photopolymerization initiator (C), and 3 parts by mass of an antioxidant (Irganox 1010 manufactured by BASF / Irgafos 168 manufactured by BASF = 1 / 1) in toluene. Using the adhesive composition, an adhesive sheet was prepared in the same manner as in Example 1. It should be noted that the storage modulus of the adhesive layer at 23°C was 0.36 MPa, and the adhesive force was 0.36 N / 25 mm.

[0144] (Example 3)

[0145] An adhesive composition was prepared by dissolving 100 parts by mass of a styrene block copolymer (A), 100 parts by mass of a liquid butadiene resin (B) having a reactive functional group, 3 parts by mass of a photopolymerization initiator (C), and 3 parts by mass of an antioxidant (Irganox 1010 manufactured by BASF / Irgafos 168 manufactured by BASF = 1 / 1) in toluene. Using the adhesive composition, an adhesive sheet was prepared in the same manner as in Example 1. It should be noted that the storage modulus of the adhesive layer at 23° C. was 0.16 MPa, and the adhesive force was 0.52 N / 25 mm.

[0146] (Comparative Example)

[0147] An adhesive sheet was prepared in the same manner as in Example 1 except that the stamp mold and the adhesive layer were not attached and vacuum laminated. In the comparative example, no irregularities were formed on the adhesive layer.

[0148] (Method for measuring elastic modulus of adhesive layer)

[0149] The storage modulus of the adhesive layer of each example was measured as follows. That is, an adhesive layer with a thickness of 25 μm was formed from the adhesive composition used in each example, and the adhesive layer was laminated in such a way that the thickness became 3 mm. Then, a UV irradiator (manufactured by Heraeus) was used at an illumination of 200 mW / cm 2 , Light intensity: 800mJ / cm 2 The laminate was irradiated with ultraviolet rays to crosslink the adhesive layer. The obtained adhesive layer was punched into a cylindrical shape with a diameter of 8 mm, and the storage modulus G' was measured by a torsional shear method at 1 Hz and 23°C using a viscoelasticity measuring device (manufactured by Rheometrics, device name "DYNAMIC ANALYZER RDAII").

[0150] (Method for measuring the adhesive force of adhesive layer)

[0151] The adhesive strength of the adhesive layer of each example was measured as follows. That is, a UV irradiator (manufactured by Heraeus) was used at an illumination of 200 mW / cm 2 , Light intensity: 800mJ / cm 2The adhesive sheet (peel sheet / adhesive layer / PET film substrate) prepared in accordance with each embodiment before being bonded to the stamp mold was irradiated with ultraviolet light, thereby crosslinking the adhesive layer. Next, the peel sheet was peeled off, and the exposed adhesive layer of the adhesive sheet was attached to the Si wafer and rolled back and forth once with a 2kg roller, thereby obtaining a sample for measurement. After the sample for measurement was placed under the conditions of 23°C and 50%RH for 24 hours, the adhesion (N / 25mm) was measured using a tensile tester (manufactured by Orientec Co., Ltd., Tensilon) at a peeling speed of 300mm / min and a peeling angle of 180 degrees. In the measurement, the conditions other than those described here were in accordance with JIS Z0237:2009.

[0152] (Performance Evaluation)

[0153] Using the adhesive sheets prepared in Examples 1 to 3 and the comparative example, a capture element test was conducted. In the test, a semiconductor chip (270µm×350µmt) attached to an LLO (Laser Lift Off) tape (manufactured by Lintec Co., Ltd., UV type, product name Ab-24, adhesive film thickness 30µm) was prepared. In addition, an adhesive sheet was attached to a quartz glass plate via a general adhesive, and the adhesive tape was arranged at a distance from the LLO tape in a manner that the adhesive sheet was parallel to the LLO tape and the adhesive surface was facing the LLO tape side. The distance (gap) between the surface of the semiconductor chip and the adhesive layer was 50µm, 100µm, 250µm or 500µm. Next, the irradiation power from the back of the LLO tape was 700mJ / cm 2 , the irradiation size of the laser is 270µm×270µm.

[0154] By irradiation of the laser, the semiconductor chip leaves the LLO tape, moves toward the adhesive sheet, and contacts the adhesive layer of the adhesive sheet. Afterwards, confirm whether the semiconductor chip is bonded to the adhesive sheet. In addition, confirm whether the position of the semiconductor chip is the same when looking down at the LLO tape (that is, whether the position of the semiconductor chip is not offset when the semiconductor chip is captured on the adhesive sheet). When the semiconductor chip is bonded to the adhesive sheet and the position of the semiconductor chip is not offset, it is determined that the capture of the semiconductor chip is successful. The results are shown in the table below. In the table, A / B means that A out of B tests were successfully captured.

[0155]

[0156] As in the comparative example, when the adhesive layer is not provided with concavoconvex, the capture of the element fails. In contrast, by providing concavoconvex in the adhesive layer, the capture of the element is easy to succeed. On the other hand, it is observed that the smaller the spacing of the convex portion, the easier it is to successfully capture. It is believed that the reason is that the smaller the spacing, the larger the contact area between the adhesive layer and the element, and therefore the greater the bonding force between the adhesive sheet and the element. It should be noted that even if the spacing is further narrowed, the contact area between the adhesive layer and the element is set to about 30%, and the capture of the element is also successful.

[0157] In addition, it was observed that increasing the gap would lead to a tendency that the capture of the element would fail easily. However, by reducing the elastic modulus of the adhesive layer as in Example 3, the capture of the element can be successful even when the gap is large. In Example 3, the capture of the element can be successful even when the spacing between the convex portions is large. In this way, it is confirmed that when capturing the element using an adhesive sheet with a concave-convex surface, a low elastic modulus of the adhesive layer is advantageous.

[0158] The present invention is not limited to the above-described embodiments, and various changes and modifications can be made within the scope of the gist of the invention.

[0159] This application claims priority based on Japanese patent application No. 2022-151756 filed on September 22, 2022 and Japanese patent application No. 2022-151757 filed on September 22, 2022, and all the contents recorded therein are incorporated herein by reference.

Claims

1. An adhesive sheet for catching a component that is separated from a holding substrate, and comprising an adhesive layer having a surface with projections and depressions. 2 . The adhesive sheet according to claim 1 , wherein the storage modulus of the adhesive layer is 0.001 MPa to 100 MPa. 3 . The adhesive sheet according to claim 1 , wherein the adhesive layer has a plurality of convex portions on the surface that are separated from each other by concave portions.

4. The adhesive sheet according to claim 1, wherein the adhesive layer has a plurality of convex portions separated from each other by boundaries determined by concave portions, The pitch of the plurality of protrusions is greater than 1 µm and less than 100 µm.

5. The adhesive sheet according to claim 1, wherein the adhesive layer has a plurality of convex portions separated from each other by concave portions, The area of ​​each of the plurality of protrusions is 10 μm 2 Above 2000µm 2 the following.

6. The adhesive sheet according to claim 1, wherein the adhesive layer has a convex portion whose boundary is determined by a concave portion, A ratio of an area of ​​the protrusion to an area of ​​the adhesive layer is not less than 1% and not more than 95%. 7 . The adhesive sheet according to claim 1 , wherein the adhesive layer is configured so that a ratio of an area of ​​the adhesive layer to one of the components relative to an area of ​​one of the components is 1% to 95%. 8 . The adhesive sheet according to claim 1 , wherein the adhesive sheet captures the element separated from the holding substrate and away from the holding substrate by an external stimulus in the adhesive layer.

9. A method for manufacturing an electronic component or a semiconductor device, the method comprising the following steps: A step of separating a component adhered to a holding substrate from the holding substrate by external stimulation; and A step of capturing the component separated from the holding substrate and away from the holding substrate in the adhesive sheet according to any one of claims 1 to 8.

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