Method for manufacturing electronic component or semiconductor device

Abstract

Provided is a novel method for facilitating the removal of an element after processing when manufacturing an electronic component or a semiconductor device, thereby increasing productivity.　In the present invention, an object to be processed for use in the manufacturing of an electronic device or a semiconductor device is bonded to a ridge-and-valley surface of an adhesive layer. A processed object is obtained by processing the object to be processed that is on the adhesive layer. The processed object is removed from the adhesive layer.

Description

Manufacturing method for electronic components or semiconductor devices

[0001] The present invention relates to a method for manufacturing an electronic component or a semiconductor device, and relates to a technique for sealing a semiconductor element, for example.

[0002] In the manufacture of electronic components or semiconductor devices, processing is performed on a workpiece, such as sealing or wiring of elements, as described in Patent Document 1. As described in Patent Document 1, the processing of the workpiece is often performed in a state where the workpiece is attached to an adhesive sheet.

[0003] International Publication No. 2018 / 181767

[0004] After processing the object to be processed, it is necessary to remove the processed object from the adhesive sheet. However, it has not been easy to easily remove the processed object from the adhesive sheet. Patent Document 1 proposes adding thermally expandable particles to the adhesive to facilitate removal of the element and increase productivity.

[0005] An object of the present invention is to provide a new method for increasing productivity by facilitating removal of processed products when manufacturing electronic components or semiconductor devices.

[0006] After extensive research, the inventors discovered that by attaching the object to be treated to the uneven surface of the adhesive layer and then processing the object, it is possible to easily remove the treated object and increase productivity, thereby solving the above-mentioned problems. After further research, they have completed the present invention.

[0007] That is, the present invention relates to the following items [1] to

[13] . [1] A method for manufacturing an electronic component or a semiconductor device, comprising: attaching a workpiece used for manufacturing an electronic component or a semiconductor device to an uneven surface of an adhesive layer; treating the workpiece on the adhesive layer to obtain a processed product; and removing the processed product from the adhesive layer. [2] The manufacturing method according to [1], wherein the workpiece is an element, a semiconductor wafer, or a panel. [3] The manufacturing method according to [1], wherein the treatment of the workpiece includes energy application treatment, liquid contact treatment, treatment under vacuum, or sealing treatment. [4] The manufacturing method according to [1], wherein the treating step seals the workpiece on the adhesive layer with a sealant to form a sealed body, and the removing step removes the sealed body including the workpiece from the adhesive layer. [5] The manufacturing method according to [4], wherein the treating step forms the sealed body so that the sealant contacts both the workpiece and the uneven surface of the adhesive layer. [6] The manufacturing method according to [4], wherein the processing step integrally seals two or more of the workpieces arranged apart on the uneven surface. [7] The manufacturing method according to [6], wherein the processing step integrally seals two or more of the workpieces, and then singulates them. [8] The manufacturing method according to [1], wherein the step of attaching the workpieces includes a step of capturing the workpieces separated from the holding substrate in the adhesive layer. [9] The manufacturing method according to [1], wherein the adhesive layer comprises a substrate and an adhesive layer formed on the substrate and having an uneven surface.

[10] The manufacturing method according to any one of [1] to [9], wherein the adhesive layer has a plurality of convex portions on the surface thereof that are spaced apart by concave portions.

[11] The manufacturing method according to any one of [1] to [9], wherein the adhesive layer has convex portions whose boundaries are defined by concave portions, and wherein a ratio of an area occupied by the convex portions to an area of ​​the adhesive layer is 1% or more and 95% or less.

[12] The manufacturing method according to any one of [1] to [9], wherein the adhesive layer is configured so that the ratio of the adhesive area between the adhesive layer and one of the objects to the area of ​​one of the objects is 1% or more and 95% or less.

[13] When the area of ​​the object is 100 mm ２The manufacturing method according to any one of [1] to [9] below.

[0008] When manufacturing electronic components or semiconductor devices, a new method can be provided for facilitating removal of processed products and increasing productivity.

[0009] Other features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings, in which the same or similar elements are designated by the same reference numerals.

[0010] The accompanying drawings are incorporated in and constitute a part of the specification, illustrate embodiments of the present invention, and are used, together with the description, to explain the principles of the present invention. A schematic diagram of an adhesive sheet according to one embodiment. A top view showing an example of unevenness possessed by an adhesive layer. A top view showing an example of unevenness possessed by an adhesive layer. A top view showing an example of unevenness possessed by an adhesive layer. A cross-sectional view showing an example of unevenness possessed by an adhesive layer. A cross-sectional view showing an example of unevenness possessed by an adhesive layer. A cross-sectional view showing an example of unevenness possessed by an adhesive layer. A cross-sectional view showing an example of unevenness possessed by an adhesive layer. A diagram explaining separation and capture of an element. A diagram explaining separation and capture of an element. A flowchart of a manufacturing method according to one embodiment. A diagram explaining a manufacturing method according to one embodiment. A diagram explaining a manufacturing method according to one embodiment. A diagram explaining a manufacturing method according to one embodiment. A diagram explaining a manufacturing method according to one embodiment. A diagram explaining an apparent contact angle.

[0011] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention as claimed, and not all combinations of features described in the embodiments are necessarily essential to the invention. Two or more of the features described in the embodiments may be combined in any desired manner. Furthermore, the same reference numerals are used to designate identical or similar components, and redundant descriptions will be omitted.

[0012] (Definitions) In this specification, the mass average molecular weight (Mw) and 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" is a term that refers to both "acrylic" and "methacrylic."

[0013] As used herein, the term "electronic component" encompasses all components used in electronics and electrical engineering, as well as all components constituting electronic devices. An "electronic component" may be formed from a semiconductor, a conductor, and / or an insulator, or a combination thereof. Examples of "electronic components" include active components (mainly formed from semiconductors, such as transistors, ICs, LSIs, VLSIs, diodes, light-emitting diodes, thyristors, three-terminal regulators, and image sensors), passive components (such as resistors, capacitors, speakers, coils, transformers, relays, piezoelectric elements, quartz oscillators, ceramic oscillators, and varistors), and structural components (such as wiring components, printed circuit boards, connectors, and switches). Furthermore, as used herein, the term "semiconductor device" refers to a general device that can function by utilizing the properties of semiconductors, such as those used in processors, memories, and sensors. Examples of "semiconductor device" include micro light-emitting diodes, mini light-emitting diodes, power devices, MEMS (Micro Electro Mechanical Systems), and controller chips.

[0014] In this specification, when one or more lower limits and one or more upper limits of a numerical range (e.g., a range of content, etc.) are described, it can be understood that any combination of the lower limit and upper limit therein is described. For example, the description "preferably 1 or more, more preferably 2 or more, even more preferably 3 or more, and preferably 9 or less, more preferably 8 or less, even more preferably 7 or less" clearly means that the numerical range may be any of 1 or more to 9 or less, 1 or more to 8 or less, 1 or more to 7 or less, 2 or more to 9 or less, 2 or more to 8 or less, 2 or more to 7 or less, 3 or more to 9 or less, 3 or more to 8 or less, and 3 or more to 7 or less.

[0015] In a method for manufacturing an electronic component or semiconductor device according to one embodiment of the present invention, an adhesive layer having an uneven surface is used. For example, in this manufacturing method, a processing is performed on a processing object attached to the adhesive layer. As will be described later, an element separated from a holding substrate may be captured in the adhesive layer in order to attach the processing object to the adhesive layer. This specification will first describe the adhesive layer having an uneven surface used in this method for manufacturing an electronic component or semiconductor device.

[0016] (Substrate) The adhesive layer may be provided on a substrate. For example, as shown in FIG. 1 , an adhesive sheet including a substrate 110 and an adhesive layer 120 can be used. In this case, processing can be performed on an object to be processed that is attached to the adhesive layer 120 of the adhesive sheet. However, it is not essential that the adhesive sheet has a substrate 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 can be used.

[0017] The substrate 110 functions as a support that supports the adhesive layer 120. The type of substrate 110 is not particularly limited, and may be a hard substrate or a flexible substrate. From the viewpoint of facilitating attachment to other members such as substrates, improving peelability, facilitating lamination, or enabling formation into a roll form, the substrate 110 is preferably a flexible substrate. For example, a resin film can be used as the substrate 110.

[0018] The resin film is a film that uses a resin-based material as a main material, and may be made of a resin material alone or may contain an additive in addition to a resin material. The resin film may be laser beam transmissive.

[0019] Specific examples of resin films include polyethylene films such as low-density polyethylene (LDPE) film, linear low-density polyethylene (LLDPE) film, and high-density polyethylene (HDPE) film; polyolefin films such as polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, ethylene-norbornene copolymer film, and norbornene resin film; ethylene copolymer films such as ethylene-vinyl acetate copolymer film, ethylene-(meth)acrylic acid copolymer film, and ethylene-(meth)acrylic acid ester copolymer film; polyvinyl chloride films such as polyvinyl chloride film and vinyl chloride copolymer film; polyester films such as polyethylene terephthalate film and polybutylene terephthalate film; polyurethane film; polyimide film; polystyrene film; polycarbonate film; and fluororesin films. Films containing a mixture of two or more materials, crosslinked films in which the resins forming these films are crosslinked, and modified films such as ionomer films may also be used. Furthermore, the substrate 110 may be a laminate film in which two or more resin films are laminated.

[0020] From the viewpoints of versatility, relatively high strength that makes it easy to prevent warping, and heat resistance, the resin film is preferably a single-layer film selected from the group consisting of polyethylene films, polyester films, and polypropylene films, or a laminate film in which two or more types of films selected from this group are laminated.

[0021] The thickness of the substrate 110 is not particularly limited, but from the viewpoint of achieving both supportability and roll winding properties, it 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.

[0022] (Adhesive Layer) The adhesive layer 120 is a layer having adhesive properties and may contain a resin. The surface of the adhesive layer 120 has irregularities. The adhesive sheet may have two or more adhesive layers 120. For example, the adhesive sheet may have a laminate of one type or two or more types of adhesive layers 120.

[0023] (Composition of adhesive layer) Examples of resins contained in the adhesive layer include rubber-based resins such as polyisobutylene-based resins, polybutadiene-based resins, and styrene-butadiene-based resins, acrylic-based resins, urethane-based resins, polyester-based resins, olefin-based resins, silicone-based resins, and polyvinyl ether-based resins. The adhesive layer may be heat-resistant, and examples of materials for the adhesive layer that have such heat resistance include polyimide-based resins and silicone-based resins. The adhesive layer may contain a copolymer having two or more types of structural 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.

[0024] The resin contained in the adhesive layer 120 is preferably an adhesive resin that exhibits adhesiveness by itself. Furthermore, the resin is preferably a polymer having a mass average molecular weight (Mw) of 10,000 or more. From the viewpoint of improving adhesive strength, the mass average molecular weight (Mw) of the resin is preferably 10,000 or more, more preferably 70,000 or more, and even more preferably 140,000 or more. From the viewpoint of suppressing the storage modulus to a predetermined value or less, the mass average molecular weight (Mw) of the resin is preferably 2,000,000 or less, more preferably 1,200,000 or less, and even more preferably 900,000 or less. From the viewpoint of improving adhesive strength, the number average molecular weight (Mn) of the resin is preferably 10,000 or more, more preferably 50,000 or more, and even more preferably 100,000 or more. From the viewpoint of suppressing the storage modulus to a predetermined value or less, the number average molecular weight (Mn) of the resin is preferably 2,000,000 or less, more preferably 1,000,000 or less, and even more preferably 700,000 or less. Note that, as described below, when the adhesive layer 120 contains a resin derived from an energy reactive resin, the 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 crosslinking reaction due to energy application. 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. When the Tg is within this range, the adhesive strength and storage modulus of the resulting pressure-sensitive adhesive can be easily controlled to fall within the ranges described below.

[0025] The amount of resin contained in the adhesive layer 120 relative to the total amount of components constituting the adhesive layer 120 can be set appropriately depending on the desired adhesive strength and storage modulus of the adhesive layer 120, but is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 50% by mass or more, even more preferably 55% by mass or more, even more preferably 60% by mass or more, and is preferably 99.99% by mass or less, more preferably 99.95% by mass or less, even more preferably 99.90% by mass or less, even more preferably 99.80% by mass or less, even more preferably 99.50% by mass or less.

[0026] 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 improves when energy is applied. Examples of energy reactive resins include energy ray reactive resins and heat reactive resins. An energy ray reactive resin refers to a resin whose elastic modulus improves when irradiated with energy rays. A heat reactive resin refers to a resin whose elastic modulus improves when heated. The type of energy ray is not particularly limited, and examples include ultraviolet rays, electron beams, and ionizing radiation. An ultraviolet ray is preferred as the energy ray, i.e., the resin is preferably an ultraviolet-reactive resin. "The resin is 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 a crosslinked energy reactive resin. When such an energy reactive resin is used, the formed uneven shape can be easily maintained by forming unevenness in the resin and then applying energy (e.g., irradiating with energy rays).

[0027] The adhesive layer may contain components other than resin, for example, the adhesive layer may contain one or more of a tackifier, a polymerization initiator, a UV absorber, and other additives.

[0028] The polymerization initiator is a component that initiates a crosslinking reaction in response to the application of energy (for example, irradiation with energy rays). When the adhesive layer contains an energy reactive resin, the adhesive layer further contains a polymerization initiator, so that the crosslinking reaction proceeds even when a relatively low amount of energy is applied.

[0029] The polymerization initiator may be, for example, a photopolymerization initiator, such as 1-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzyl phenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, dibenzyl, diacetyl, or 8-chloroanthraquinone.

[0030] The adhesive layer may contain one type of polymerization initiator or two or more types of polymerization initiators. When the adhesive layer contains a polymerization initiator, the content of the polymerization initiator in the adhesive layer is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and even more preferably 1% by mass or more, from the viewpoint of proceeding with the crosslinking reaction at an appropriate rate, and is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 2% by mass or less.

[0031] Examples of UV absorbers include benzotriazole compounds, oxazolic acid amide compounds, and benzophenone compounds.

[0032] Other additives that may be contained in the adhesive layer are not particularly limited, but include, for example, hindered amine-based, benzophenone-based, or benzotriazole-based light stabilizers; phenol-based antioxidants such as hindered phenol-based compounds, aromatic amine-based antioxidants, sulfur-based antioxidants, or phosphorus-based antioxidants such as phosphate ester-based compounds; resin stabilizers such as imidazole-based resin stabilizers, dithiocarbamate-based resin stabilizers, phosphorus-based resin stabilizers, or sulfur ester-based resin stabilizers; fillers, pigments, extenders, and softeners.

[0033] When the adhesive layer contains these additives, the content of the additives in the adhesive layer is preferably 0.0001% by mass or more, more preferably 0.01% by mass or more, particularly preferably 0.1% by mass or more, even more preferably 1% by mass or more, and preferably 20% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less.

[0034] (Shape of adhesive layer) The surface of the adhesive layer has irregularities. As will be described later, after processing the object to be treated attached to the adhesive layer, the object to be treated is removed from the adhesive layer. If the surface of the adhesive layer is flat, the adhesive layer and the object to be treated are in close contact. In this case, even if an attempt is made to remove the object to be treated from the adhesive layer, it is difficult for air to get between the adhesive layer and the object to be treated, so a sufficiently large force is required to remove the object to be treated from the adhesive layer. On the other hand, since there is a gap between the adhesive layer with an irregular surface and the object to be treated, it becomes easy to remove the object to be treated from the adhesive layer.

[0035] Furthermore, as described below, in order to attach the workpiece to the adhesive layer, the workpiece separated from the holding substrate can be captured by the adhesive layer. Specifically, the adhesive layer can capture the workpiece at the convex portions. At this time, the gas compressed between the workpiece and the adhesive layer as the workpiece and the adhesive layer approach each other can escape to the concave portions of the adhesive layer. In this way, the unevenness of the adhesive layer can alleviate the pressure generated between the workpiece and the adhesive layer. Therefore, it is possible to prevent the pressure generated between the workpiece and the adhesive layer from shifting the holding position of the workpiece on the adhesive layer.

[0036] As described above, if the surface of the adhesive layer has recesses, the force required to remove the object from the adhesive layer can be adjusted by controlling the contact area between the object and the adhesive layer. Furthermore, if the surface of the adhesive layer has recesses, the pressure generated between the object and the adhesive layer can be alleviated. Therefore, the specific shape of the recesses on the surface of the adhesive layer is not limited.

[0037] For example, in one embodiment, the adhesive layer has a plurality of convex portions on its surface, separated from one another by concave portions. Each of the plurality of convex portions may be separated by a concave portion that extends continuously throughout the entire adhesive layer. Providing a continuous concave portion around such convex portions allows air to more easily penetrate between the adhesive layer and the object to be treated, thereby facilitating removal of the object from the adhesive layer. Furthermore, in one embodiment, the concave portions located around each of the plurality of convex portions extend to the edge of the adhesive layer. Providing a concave portion that extends continuously to the edge of the adhesive layer allows air to more easily penetrate between the object to be treated and the adhesive layer. Furthermore, these configurations allow air compressed between the object to be treated and the convex portions to efficiently escape to the outside of the object to be treated, thereby enhancing the pressure relief effect. Figures 2A to 2C are top views showing the shape of such an adhesive layer.

[0038] As shown in FIG. 2A, convex portions may be regularly arranged on the surface of the adhesive layer. Regularly arranging the convex portions means that the convex portions are arranged in a straight line at regular intervals. Alternatively, as shown in FIG. 2B, the convex portions may be arranged so that the intervals between them vary regularly. In the example of FIG. 2B, the intervals between the convex portions are short in the center of the adhesive layer and long in the peripheral portion of the adhesive layer. This configuration increases the holding power of the adhesive layer, while allowing air to easily enter between the adhesive layer and the object from the peripheral portion of the object via the wide recesses, thereby efficiently releasing pressure from the peripheral portion of the object. Furthermore, the convex portions may be irregularly arranged.

[0039] 2C is a top view showing another shape of the adhesive layer. As shown in FIG. 2C, stripe-shaped protrusions may be provided on the surface of the adhesive layer. In FIG. 2C, linear protrusions having a constant width are arranged at regular intervals. On the other hand, as in FIG. 2B, the width or interval of the linear protrusions may vary regularly, or the linear protrusions may be arranged irregularly.

[0040] The pitch of the convex portions is preferably 1 μm or more, more preferably 5 μm or more, even more preferably 10 μm or more, and even more preferably 15 μm or more, from the viewpoint of facilitating removal of the object to be treated or enhancing the pressure relief effect. Here, the pitch of the convex portions refers to the smallest distance among all the distances between the convex portions in the entire adhesive layer. For example, in the case of FIG. 2A, the pitch of the convex portions represents the distance between the convex portions on a straight line where the convex portions are arranged at a constant interval. When the convex portions are arranged on multiple straight lines, the pitch represents the distance between the convex portions on the straight line where the convex portions are arranged at the shortest interval. Furthermore, in the case of FIG. 2C, the pitch of the convex portions represents the distance between the linear convex portions. In this specification, the distance between the convex portions refers to the distance between the centers of the convex portions.

[0041] On the other hand, narrowing the pitch of the convex portions increases the contact area between the adhesive layer and the object to be processed, thereby suppressing misalignment during capture. Furthermore, as described below, in one embodiment, the object to be processed on the adhesive is sealed with a sealant. In this case, a finer structure on the surface of the adhesive layer reduces the wettability of the sealant to the surface of the adhesive layer before curing, making it less likely for the sealant to penetrate the unevenness. This phenomenon of reduced wettability on a surface with a fine structure is generally referred to as the lotus effect. For example, lotus leaves are known to exhibit high water repellency due to their surface having a fine structure with a pitch of 20 to 30 μm and a height of approximately 10 μm. One reason for this reduced wettability is the formation of air chambers in the recesses on the surface when a fluid contacts the surface of the adhesive layer. From these perspectives, the pitch of the convex portions is preferably 100 μm or less, more preferably 75 μm or less, even more preferably 50 μm or less, even more preferably 35 μm or less, and even more preferably 25 μm or less.

[0042] 2B , the minimum interval among all the intervals between the convex portions in the center of the adhesive layer may be shorter than the minimum interval among all the intervals between the convex portions in the peripheral portion of the adhesive layer. Here, the central portion refers to, for example, a circular region having one-quarter of the area of ​​the adhesive layer and centered on the center of gravity of the adhesive layer, and the peripheral portion refers to, for example, the entire area of ​​the adhesive layer other than the central portion.

[0043] The specific shape of the protrusions is not particularly limited. For example, the protrusions may have a pillar (column) shape. As a specific example, the protrusions may have a cylindrical shape or a prismatic shape. Furthermore, as described above, the protrusions may extend in a line shape, or may extend in a curved shape such as a wavy shape. Furthermore, these protrusions may be tapered.

[0044] 3A shows a cross-sectional view of an adhesive layer according to one embodiment, passing through a convex portion and perpendicular to the surface of the adhesive layer. The convex portion shown in FIG. 3A is tapered, i.e., the convex portion is tapered. Furthermore, as shown in FIG. 3A, the tip of the convex portion may be curved. This configuration further reduces the impact when the adhesive layer comes into contact with the workpiece separated from the holding substrate, making it easier for the adhesive layer to hold the workpiece in place. Alternatively, the tip of the convex portion may be flat.

[0045] As shown in Figure 3A, the surface of the adhesive layer may have a flat recess and a protrusion protruding from the recess, and the adhesive layer may have a plurality of spaced apart protrusions bounded by the recess.

[0046] As another example, the protrusions may be hemispherical or part of a sphere as shown in Figure 3B. Furthermore, the protrusions may be T-shaped as shown in Figure 3C. As yet another example, the protrusions may be in the shape of a collection of particles, a mushroom shape, the surface of a lotus leaf, or a needle shape. As yet another example, the surface of the adhesive layer may be rough or fibrous, and such a surface may also be said to have irregularities.

[0047] From the viewpoint of maintaining adhesiveness, the width or diameter of each convex portion is preferably 1 μm or more, more preferably 2 μm or more, even more preferably 5 μm or more, and even more preferably 10 μm or more. On the other hand, from the viewpoint of facilitating removal of the workpiece or enhancing the pressure relaxation effect, the width or diameter of each convex portion is preferably 100 μm or less, more preferably 50 μm or less, even more preferably 30 μm or less, and even more preferably 20 μm or less. Here, the width and diameter of the convex portion refer to the minimum and maximum distances (represented by B in FIG. 3A ) between two parallel lines that contact the convex portion from both sides on the surface of the concave portion, respectively.

[0048] In addition, the area of ​​each projection is set to 10 μm from the viewpoint of maintaining adhesiveness. ２ It is preferable that the thickness is 20 μm or more. ２ More preferably, it is 30 μm or more. ２ On the other hand, the area of ​​each protrusion is preferably 2000 μm or more from the viewpoint of facilitating removal of the workpiece or enhancing the pressure relaxation effect. ２ Preferably, it is 1000 μm or less. ２ More preferably, it is 500 μm or less. ２ It is more preferable that the area of ​​the convex portion is equal to or less than 1 / 2 mm. Here, the area of ​​the convex portion means the area of ​​the portion protruding from the surface of the concave portion (the area of ​​a circle with diameter B in the case of FIG. 3A).

[0049] Furthermore, from the viewpoint of facilitating air penetration into the recesses, the height of each convex portion is preferably 1 μm or more, more preferably 3 μm or more, and even more preferably 5 μm or more. On the other hand, from the viewpoint of improving dimensional stability, the height of each convex portion is preferably 20 μm or less, more preferably 15 μm or less, and even more preferably 10 μm or less. Here, the height of the convex portion is represented by H in FIG. 3A.

[0050] Furthermore, the area of ​​the adhesive layer occupied by the plurality of protrusions is preferably 1% or more, more preferably 5% or more, even more preferably 10% or more, even more preferably 18% or more, and even more preferably 40% or more, from the viewpoint of maintaining adhesiveness, while the area of ​​each protrusion is preferably 95% or less, more preferably 75% or less, and even more preferably 60% or less, from the viewpoint of enhancing the pressure relaxation effect.

[0051] The unevenness of the adhesive layer may be designed according to the shape of the workpiece. For example, from the viewpoint of maintaining adhesion, the ratio of the adhesive area between the adhesive layer and one workpiece to the area of ​​one workpiece is preferably 1% or more, more preferably 2% or more, even more preferably 3% or more, even more preferably 4% or more, even more preferably 5% or more, even more preferably 7% or more, and even more preferably 10% or more. On the other hand, from the viewpoint of facilitating removal of the workpiece or enhancing the pressure relief effect, the area of ​​each convex portion is preferably 95% or less, more preferably 70% or less, even more preferably 50% or less, and even more preferably 30% or less. In the case of Figure 3A, the adhesive area corresponds to the area of ​​a circle with a diameter T. Note that the adhesive area may change if the position of the workpiece on the adhesive layer is shifted. In this case, it is preferable that the adhesive area ratio falls within the above range regardless of the position of the workpiece.

[0052] (Other Layers) The above-mentioned adhesive sheet may have layers other than the substrate 110 and the adhesive layer 120. For example, an additional adhesive layer may be provided on the surface of the substrate 110 opposite the adhesive layer 120. The adhesive sheet can be attached to another substrate such as quartz glass via such an adhesive layer. The type of the additional adhesive layer is not particularly limited, and the additional adhesive layer can be formed using, for example, a general adhesive.

[0053] (Method for manufacturing adhesive layer and adhesive sheet) There are no particular limitations on the method for manufacturing the adhesive layer and adhesive sheet. For example, an adhesive sheet having an adhesive layer 120 provided on a substrate 110 can be produced as follows. First, an organic solvent is added to a raw material composition containing each of the components of the adhesive layer described above to prepare a solution of the raw material composition. This solution is then applied to the substrate to form a coating film, which is then dried, thereby providing an adhesive layer on the substrate 110. Furthermore, by performing a process to provide irregularities on the surface of this adhesive layer, an adhesive layer 120 having irregularities can be formed.

[0054] Examples of organic solvents used to prepare the raw material composition solution include toluene, ethyl acetate, and methyl ethyl ketone. The solids concentration of the raw material composition solution is preferably 10% by mass or more, more preferably 25% by mass or more, and even more preferably 45% by mass or more, and is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 65% ​​by mass or less. Examples of methods for applying the solution include spin coating, spray coating, bar coating, knife coating, roll coating, roll knife coating, blade coating, die coating, gravure coating, and printing methods (e.g., screen printing and inkjet printing).

[0055] There are no particular limitations on the process for providing the surface of the adhesive layer with irregularities. For example, irregularities can be provided on the surface of the adhesive layer using an imprinting method. In the imprinting method, a mold having a surface shape complementary to the irregularities to be provided can be used. Specifically, irregularities can be provided on the surface of the adhesive layer by heating the adhesive layer while pressing the adhesive layer provided on the substrate with the mold. A more specific method involves pressing the adhesive layer with the mold, heating the adhesive layer, and maintaining the temperature for a predetermined period of time, after which the adhesive layer is cooled and the mold is removed. When heating the adhesive layer, for example, the adhesive layer can be heated to a temperature higher than the softening point of the adhesive layer. The time for maintaining the adhesive layer in the heated state is also not particularly limited, and may be maintained for, for example, 10 seconds or more or 10 minutes or less. A specific method for heating the adhesive layer while pressing the adhesive layer with the mold includes vacuum laminating the adhesive layer provided on the substrate and the mold. Instead of performing the two-stage process of forming the adhesive layer and forming the irregularities, the adhesive layer 120 having irregularities on its surface may be formed on the substrate 110 in a single stage.

[0056] Alternatively, a solution of the raw material composition can be spray-coated to provide an adhesive layer having a rough surface. Furthermore, a filler can be added to the solution of the raw material composition, and the solution can be applied to provide an adhesive layer having a rough or fibrous surface. As yet another method, a printing method such as an inkjet method can be used to apply the solution of the raw material composition according to a desired pattern, thereby providing an adhesive layer having a textured shape directly on a substrate.

[0057] Furthermore, a pressure-sensitive adhesive sheet without a substrate 110 can be produced by forming a composition containing each component of the pressure-sensitive adhesive layer into a sheet. Furthermore, the pressure-sensitive adhesive layer may be formed by applying a liquid pressure-sensitive adhesive containing each component of the pressure-sensitive adhesive layer to any object. In these cases, the pressure-sensitive adhesive layer may be subjected to a treatment to provide irregularities on its surface after formation, or the pressure-sensitive adhesive layer may be formed by a method that forms irregularities on its surface.

[0058] (Method for Manufacturing Electronic Component or Semiconductor Device Using Adhesive Layer) Hereinafter, a method for manufacturing an electronic component or semiconductor device using the above-described adhesive layer will be described in detail with reference to the flowchart of FIG.

[0059] (S10: Attachment of Workpiece) In step S10, a workpiece used to manufacture an electronic component or semiconductor device is attached to the uneven surface of the adhesive layer. For example, as shown in FIG. 6A, workpiece 520 can be attached to the surface of adhesive sheet 510. There are no particular limitations on the method for attaching the workpiece. For example, the workpiece can be placed on the adhesive layer using a device such as a flip-chip bonder or a die bonder. The layout and number of workpieces can be determined as appropriate depending on the shape of the sealed body to be manufactured and the production volume.

[0060] The type of workpiece is not particularly limited. The workpiece may be, for example, an element, a wafer, a panel, or a substrate. The element may be, for example, a semiconductor chip such as an LED chip, a semiconductor chip with a protective film, or a semiconductor chip with a die attach film (DAF). The element may also be a micro light-emitting diode, a mini light-emitting diode, a power device, a MEMS (Micro Electro Mechanical Systems), or a controller chip, or a component thereof. The element may also be an individualized object such as a wafer, a panel, or a substrate. The element may have, for example, a circuit surface on which an integrated circuit having circuit elements such as transistors, resistors, and capacitors is formed.

[0061] The size of the element is not particularly limited. For example, the size of the element is 100 μm. ２ More than 500μm ２ or more, or 1000 μm ２ On the other hand, the size of the element may be 100 mm or more. ２ Below, 25mm ２ Less than or equal to 1 mm ２ When small-sized elements are used, the laser lift-off method described below is suitable for attaching the elements because it is easy to selectively separate small elements.

[0062] The workpiece is not necessarily limited to an individualized object, and may be, for example, various types of wafers, panels, or substrates that are not individualized.

[0063] Examples of wafers include semiconductor wafers such as silicon wafers, silicon carbide (SiC) wafers, and compound semiconductor wafers (e.g., gallium phosphide (GaP) wafers, gallium arsenide (GaAs) wafers, indium phosphide (InP) wafers, and gallium nitride (GaN) wafers). The size of the wafer is not particularly limited, but may be 8 inches (diameter 200 mm) or larger, and preferably 12 inches (diameter 300 mm) or larger. The shape of the wafer is not limited to a circle, and may be an angular shape such as a square or rectangle.

[0064] The panel may be a fan-out type semiconductor package (e.g., FOWLP or FOPLP). That is, the workpiece may be a semiconductor package before or after singulation in a fan-out type semiconductor package manufacturing technique. The size of the panel is not particularly limited, but may be, for example, a rectangular substrate of about 300 to 700 mm.

[0065] The substrate may be a glass substrate, a sapphire substrate, or a compound semiconductor substrate.

[0066] The following description will be focused on the case where an element is used as the object to be processed, but the method described below can also be applied to the case where other objects are used.

[0067] When using an adhesive layer having an uneven surface, it is preferable to transfer the element from the support substrate to the adhesive layer by a method including a step of separating the element from the support substrate and a step of capturing the element on the adhesive layer. In this way, the element can be attached to the uneven surface of the adhesive layer. Such a method will be described below.

[0068] (S10-1: Preparation of holding substrate) First, a holding substrate to which elements are attached is prepared. The type of 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 this adhesive layer may be provided on a substrate. In this case, the holding substrate can hold the elements via the adhesive layer. The substrate may be a resin film or a hard substrate.

[0069] The method for preparing such a holding substrate for holding elements is not particularly limited. For example, a semiconductor wafer can be attached to the holding substrate, and then the semiconductor wafer can be diced. By dicing the semiconductor wafer in this manner, elements can be obtained, and thus a holding substrate with elements attached thereto can be obtained.

[0070] As another method, a semiconductor wafer can be diced, and the resulting elements can be transferred to a holding substrate to obtain a holding substrate with elements attached thereto. For example, a semiconductor wafer held on a wafer substrate can be diced, and then the resulting elements can be brought into close contact with the adhesive layer of the holding substrate. Then, an external stimulus such as laser light can be applied to reduce the adhesive strength between the wafer substrate and the elements. By this process, the elements can be transferred from the wafer substrate to the holding substrate.

[0071] As will be described later, the element can be separated from the holding substrate by irradiation with laser light (laser lift-off method). When using such a method, the adhesive layer of the holding substrate preferably contains a laser beam absorbent. Examples of the laser beam absorbent include one or more selected from pigments and dyes.

[0072] (S10-2: Separation of the element) Next, the element attached to the holding substrate is separated from the holding substrate by an external stimulus. The type of external stimulus is not particularly limited, but examples include application of energy, cooling, stretching of the holding substrate, and physical stimulus (for example, pressing the back surface of the holding substrate with a pin, etc.). By using one or more of these external stimuli, the bonding force between the holding substrate and the element can be reduced, and the element can be separated from the holding substrate.

[0073] As described below, after separating the elements, the elements can be captured so that the relative arrangement of the elements on the holding substrate differs from the relative arrangement of the elements on the adhesive layer. To achieve this, it is preferable to selectively separate a portion of the elements attached to the holding substrate. Therefore, an external stimulus can be selectively applied to a portion of the elements attached to the holding substrate or to the attachment site of the element on the holding substrate.

[0074] Examples of energy application methods include local heating, light irradiation, and heat ray irradiation. Examples of light irradiation methods include infrared irradiation, visible light irradiation, and laser light irradiation. Preferably, the external stimulus is laser light irradiation, i.e., the element is separated from the holding substrate by laser lift-off. In this case, the laser light is directed toward the attachment portion of the holding substrate where the specific element is attached. For example, such laser light irradiation can be performed from the side of the holding substrate opposite the element. This generates gas at the contact portion between the specific element and the holding substrate. For example, when the laser light is absorbed by the adhesive layer, at least a portion of the adhesive layer sublimes, generating gas. This sublimation of at least a portion of the adhesive layer reduces the adhesion area between the specific element and the adhesive layer, thereby reducing the adhesive strength between the specific element and the holding substrate. Furthermore, the pressure of the generated gas also reduces the adhesive strength between the specific element and the holding substrate. As a result, the specific element is separated from the holding substrate.

[0075] The conditions for irradiating the laser beam are not particularly limited. From the viewpoint of selectively and efficiently separating some elements, the frequency of the laser beam is preferably 10,000 Hz or more and 100,000 Hz or less. The beam diameter of the laser beam is preferably 10 μm or more, more preferably 20 μm or more, and is preferably 100 μm or less, more preferably 40 μm or less. The output of the laser beam is preferably 0.1 W or more and 10 W or less. The scanning speed of the laser beam is preferably 50 mm / sec or more and 2000 mm / sec or less.

[0076] (S10-3: Capturing element) Furthermore, the element separated from the holding substrate is captured by the adhesive layer. Specifically, the element moves relatively away from the holding substrate. Furthermore, the element moves relatively closer to the adhesive layer. Then, the element comes into contact with the adhesive layer of the adhesive sheet, and the element is captured by the adhesive layer.

[0077] As shown in FIG. 4A , by positioning position A on the adhesive sheet 450 so as to face the element 420 attached to the holding substrate 410, the separated element 420 is captured at position A on the adhesive sheet 450. Furthermore, as shown in FIG. 4B , by positioning position B on the adhesive sheet 450 so as to face the element 430 attached to the holding substrate 410, the separated element 430 is captured at position B on the adhesive sheet 450. In this way, the separation and capture of the element can be performed while changing the relative position of the holding substrate and the adhesive layer in the planar direction. In this way, the element can be positioned so that the relative arrangement of the multiple elements on the holding substrate differs from the relative arrangement of the multiple elements on the adhesive layer. However, as already explained, when an adhesive layer having a flat surface is used, the element 420 in the example of FIG. 4A may be captured at a position shifted from position A due to the pressure generated between the element and the adhesive layer. However, by providing the adhesive layer with an uneven surface, the pressure generated between the element and the adhesive layer is alleviated, making it easier to capture the element at a desired position on the adhesive layer.

[0078] In one embodiment, the holding substrate and adhesive layer are stationary, and the element separated from the holding substrate moves toward the adhesive layer. For example, when using a laser lift-off method, the element can move toward the adhesive layer due to the pressure of gas generated by irradiation with laser light. However, it is not essential that the element move. For example, the holding substrate may move away from the element. Alternatively, the adhesive layer may move toward the element.

[0079] (S20: Processing of the object to be processed) In step S20, the object to be processed on the adhesive layer is processed. The processing method is not particularly limited. For example, processing such as forming wiring, forming a back metal, cleaning, plating, singulation, and thinning can be performed. In addition, the processing of the object to be processed may include energy application processing (e.g., heating or irradiation with energy rays such as light), liquid contact processing (e.g., etching), vacuum processing (e.g., vacuum deposition or sputtering), or sealing processing. A processed product can be obtained by such processing. Below, as an example, the case of sealing an element will be described.

[0080] In one embodiment, an encapsulated body is formed by encapsulating elements on an adhesive layer with an encapsulant. First, the elements attached to the adhesive layer are covered with an encapsulant. Specifically, as shown in FIG. 6B , the elements 520 can be covered with an encapsulant 530 so that the exposed surfaces of the elements 520, for example, the surface and side surfaces of the elements 520 opposite the adhesive sheet 510, are covered. On the other hand, when covering the elements 520 with the encapsulant 530, the surface of the elements 520 facing the adhesive sheet 510 does not need to be covered. In this case, two or more elements 520 may be integrally covered with the encapsulant 530. In the example of FIG. 6B , two or more elements 520 spaced apart on an uneven surface are encapsulated integrally. In this case, the gaps between the two or more elements 520 are filled with the encapsulant 530. After the elements attached to the adhesive layer are covered with the encapsulant, the encapsulant is then cured. By curing the encapsulant 530, an encapsulated body 550 including the elements 520 is formed, as shown in FIG. 6C . By this method, the encapsulant 550 can be formed so that the encapsulant contacts both the element and the uneven surface of the adhesive layer.

[0081] As described above, due to the lotus effect, fluids are less likely to penetrate the microstructure of the uneven surface of the adhesive layer. Therefore, the sealant 550 can be formed so that the recesses on the surface of the adhesive sheet 510 are not filled with the sealant 530, and air enters these recesses. From the viewpoint of making it difficult for the sealant 530 to penetrate the unevenness of the adhesive layer, the apparent contact angle (the contact angle when the uneven surface is considered to be a flat surface, represented by θ in FIG. 7 ) between the uneven surface of the adhesive layer and the sealant before curing is preferably greater than 90°, more preferably greater than 100°, and even more preferably greater than 110°. From the same viewpoint, it is preferable to select an adhesive so that, when a flat adhesive layer is formed, the contact angle between this layer and the sealant before curing is preferably greater than 90°, more preferably greater than 100°, and even more preferably greater than 110°. Preferably, the apparent contact angle between the uneven surface of the adhesive layer and the sealing material before curing is larger than the contact angle between this layer and the sealing material before curing when a flat layer of adhesive is formed.

[0082] The encapsulant has a function of protecting the device and its associated elements from the external environment. There are no particular limitations on the type of encapsulant. The encapsulant has curing properties from the viewpoints of mechanical strength, heat resistance, insulating properties, etc.

[0083] Examples of the encapsulant include a thermosetting resin composition and an energy ray-curable resin composition. Examples of the thermosetting resin contained in the thermosetting resin composition include an epoxy resin, a phenolic resin, and a cyanate resin. From the viewpoints of mechanical strength, heat resistance, insulating properties, moldability, and the like, an epoxy resin is preferred as the thermosetting resin. In addition to the thermosetting resin, the thermosetting resin composition may contain, as necessary, a curing agent such as a phenolic resin-based curing agent or an amine-based curing agent, a curing accelerator, an inorganic filler such as silica, or an additive such as an elastomer. The encapsulant may be solid or liquid at room temperature. Furthermore, the form of the encapsulant that is solid at room temperature is not particularly limited, and may be, for example, granular or sheet-like.

[0084] The method for covering the element with the encapsulant is not particularly limited, and examples thereof include roll lamination, vacuum pressing, vacuum lamination, spin coating, die coating, transfer molding, and compression molding. In these methods, the encapsulant can be heated during coating to impart fluidity to the encapsulant in order to improve the filling ability of the encapsulant.

[0085] Compression molding is preferably used as a method for sealing elements. In compression molding, a sealing material is filled into a cavity having a desired shape and pressed to obtain a sealed body having a desired shape. For example, in the example of FIG. 6B, a sealing material 530 is filled into a cavity in a mold 540. The molding pressure at this time is, for example, 0.1 MPa or more, preferably 0.2 MPa or more, more preferably 0.3 MPa or more, and for example, 2.0 MPa or less, preferably 1.8 MPa or less, more preferably 1.6 MPa or less. Furthermore, compression molding may be performed while reducing the pressure inside the cavity. Furthermore, when performing compression molding, the sealing material can be cured during pressure application.

[0086] When a thermosetting resin composition is used as the encapsulant, the encapsulant can be cured by heating the encapsulant. The heating temperature can be selected depending on the type of encapsulant, but is, for example, 30°C or higher, preferably 50°C or higher, more preferably 70°C or higher, and for example, 180°C or lower, preferably 170°C or lower, more preferably 150°C or lower. The heating time is, for example, 5 seconds or higher, preferably 10 seconds or higher, more preferably 15 seconds or higher, and for example, 60 minutes or lower, preferably 45 minutes or lower, more preferably 30 minutes or lower.

[0087] As described above, two or more objects to be treated that are spaced apart on the textured surface can be sealed together. Furthermore, after sealing two or more objects together, they may be further singulated. For example, a package assembly containing two or more objects to be treated can be produced by sealing them together, and then the assembly can be singulated to produce a plurality of packages each containing an object to be treated.

[0088] The encapsulated body thus obtained can be further processed. For example, a redistribution layer can be formed on the surface of the encapsulated body. That is, the manufacturing method of an electronic component or semiconductor device according to this embodiment can be used in a fan-out process such as FOWLP or FOPLP. For example, an area larger than the element size can be covered with the encapsulant, and further, a redistribution layer and external electrodes can be formed not only on the circuit surface of the element but also on the surface of the encapsulant.

[0089] The above-described treatments for the workpieces can also be used in combination. For example, two or more workpieces can be integrally sealed, a rewiring layer can be formed on the surface of the sealing material, and then the resulting structure can be singulated.

[0090] (S30: Removal of Processed Result) In step S30, the processed result obtained by processing the workpiece is removed from the adhesive layer. When the elements are sealed in step S20, encapsulant 550 is removed from adhesive sheet 510 as shown in FIG. 6D . As described above, air is trapped in the recesses on the surface of adhesive sheet 510, and therefore encapsulant 550 is attached to adhesive sheet 510, but encapsulant 550 has portions that are not in close contact with adhesive sheet 510. Therefore, encapsulant 550 can be more easily removed from adhesive sheet 510 than when the adhesive layer does not have any irregularities.

[0091] When further processing is performed on the surface of the sealed body that was previously attached to the adhesive layer, a reinforcing member may be attached to the surface of the sealed body opposite the surface that was previously attached to the adhesive layer, as necessary, to improve the handleability of the sealed body. The reinforcing member is not particularly limited, and for example, a reinforcing plate with excellent heat resistance, such as a glass epoxy resin, can be used. Such a reinforcing plate can be attached to the entire surface of the sealed body. The reinforcing member can be attached, for example, via an adhesive layer. Since the reinforcing member will be removed after further processing, it is preferable to select an adhesive layer that allows the reinforcing member to be peeled off. Such a reinforcing member can be attached, for example, by laminating a thermosetting adhesive layer and a reinforcing plate in this order to the sealed body. If necessary, both the reinforcing plate side and the adhesive layer side may be sandwiched between plate-like members and pressed under predetermined conditions of temperature, time, and pressure. In this case, a metal plate such as stainless steel can be used as the plate-like member.

[0092] The invention is not limited to the above-described embodiment, and various modifications and variations are possible within the scope of the gist of the invention.

[0093] 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, the entire contents of which are incorporated herein by reference.

Claims

1. A step of adhering a workpiece used for manufacturing electronic components or semiconductor devices to the uneven surface of the adhesive layer; A step of obtaining a processed product by performing a process on the object to be processed on the adhesive layer; removing the processed product from the adhesive layer; A method for manufacturing an electronic component or a semiconductor device, comprising:

2. The manufacturing method according to claim 1 , wherein the workpiece is a device, a semiconductor wafer, or a panel.

3. The method according to claim 1 , wherein the treatment of the workpiece includes an energy application treatment, a liquid contact treatment, a vacuum treatment, or a sealing treatment.

4. In the step of performing the treatment, the object to be treated on the adhesive layer is sealed with a sealant to form a sealed body, The manufacturing method according to claim 1 , wherein in the removing step, the sealing body including the object to be treated is removed from the adhesive layer.

5. The method according to claim 4 , wherein in the step of performing the treatment, the sealant is formed so that the sealant contacts both the object to be treated and the uneven surface of the adhesive layer.

6. The method according to claim 4 , wherein in the step of performing the treatment, two or more of the objects to be treated that are arranged separately on the uneven surface are integrally sealed.

7. The manufacturing method according to claim 6 , wherein in the step of performing the treatment, two or more of the objects to be treated are sealed together and then singulated.

8. The manufacturing method according to claim 1 , wherein the step of adhering the object to be treated includes a step of capturing the object to be treated separated from a holding substrate in the adhesive layer.

9. The method according to claim 1 , wherein the adhesive layer comprises a substrate and an adhesive layer formed on the substrate and having an uneven surface.

10. The method according to claim 1 , wherein the adhesive layer has a surface having a plurality of protrusions spaced apart from each other via recesses.

11. the adhesive layer has protrusions bounded by recesses; The method according to claim 1 , wherein a ratio of an area occupied by the convex portions to an area of ​​the adhesive layer is 1% or more and 95% or less.

12. The manufacturing method according to any one of claims 1 to 9, wherein the adhesive layer is configured so that a ratio of an adhesion area between the adhesive layer and one of the workpieces to an area of ​​one of the workpieces is 1% or more and 95% or less.

13. The area of ​​the workpiece is 100 mm ２ The method of any one of claims 1 to 9, wherein: