Components for temporary fixing of electronic parts

Abstract

This invention provides an electronic component temporary fixing member that reduces residue from the electronic component temporary fixing member on the support body when the support body is peeled off from the electronic component temporary fixing member. The electronic component temporary fixing member of this invention comprises: a core material, a release layer provided on a first surface of the core material, and an adhesive layer provided on a second surface of the core material facing the first surface. The release layer contains a filler and has a portion in which the area ratio of the filler in the cross-section of the release layer perpendicular to the first surface is 8.0% to 92%.

Description

[Technical Field]

[0001] The present invention relates to a component for temporarily fixing electronic components when forming a substrate on which electronic components such as semiconductors are mounted. [Previous Technology]

[0002] In recent years, electronic components such as semiconductors have continued to develop rapidly, further increasing the demand for miniaturization and thinning. Moreover, the demand for miniaturization and thinning of substrates that house electronic components such as semiconductors is increasing, and their forms are becoming more complex year by year.

[0003] For example, in the RDL priority process of one method for forming micro-wiring, a temporary fixing member (temporary fixing material layer) is first formed on a support, and an RDL layer (rewiring layer) having a thinned substrate is formed on top of the temporary fixing member. The support has the function of supporting the RDL layer formed on top of the temporary fixing member below the temporary fixing member. After the RDL layer (rewiring layer) is formed, laser light is irradiated onto the temporary fixing member from the support side, separating the support from the temporary fixing member. Subsequently, the temporary fixing member is removed from the RDL layer.

[0004] When separating the support body from the temporary fixing component, from the viewpoint of reusing the support body, it is required that the residue of the temporary fixing component not remain on the support body as much as possible. Therefore, an adhesive sheet for temporary fixing of electronic components is proposed, which has a photothermal conversion layer and a thermal decomposition layer directly disposed on the photothermal conversion layer, and the 5% weight reduction temperature of the thermal decomposition layer is lower than the 5% weight reduction temperature of the photothermal conversion layer (Patent Document 1).

[0005] In Patent Document 1, the photothermal conversion layer of the core material of the temporary fixing layer is a layer that absorbs light of a specific wavelength and converts that light into heat. The heating of the photothermal conversion layer causes the thermal decomposition layer of the release layer of the temporary fixing layer to heat up, resulting in the decomposition of the thermal decomposition layer. As a result of the decomposition of the thermal decomposition layer, the temporary fixing layer formed on the support exhibits peelability, causing the support to peel off from the temporary fixing layer. The release layer of the temporary fixing layer is the layer to which the support is adhered. An adhesive layer of the temporary fixing layer is provided on the core material of the temporary fixing layer, and a substrate on which electronic components are mounted is formed.

[0006] However, although the temporary fixing layer in Patent Document 1 exhibits peelability by absorbing laser light through a photothermal conversion layer to heat up and decompose the thermal decomposition layer, the peelability only occurs at the interface between the thermal decomposition layer of the release layer and the photothermal conversion layer of the core material. Similar to the temporary fixing layer in Patent Document 1, if peelability is observed at the interface between the release layer and the core material when the support is peeled off from the temporary fixing layer, residue from the thermally decomposed release layer will still remain on the support. Therefore, there is a need to improve the reduction of residue on the support. Furthermore, to remove the release layer residue from the support, the support must be cleaned with a solvent, which complicates the manufacturing process of the substrate containing electronic components and increases the environmental impact. [Previous Patent Documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2023-049530 [Summary of the Invention]

[0008] [Problem to be Solved by the Invention] In view of the above, the object of the present invention is to provide an electronic component temporary fixing member that reduces the residue of the electronic component temporary fixing member on the support body when the support body is peeled off from the electronic component temporary fixing member. [Means for Solving the Problem]

[0009] The main structure of the electronic component temporary fixing member of the present invention is as follows. [1] An electronic component temporary fixing member comprises: a core material, a release layer provided on a first surface of the core material, and an adhesive layer provided on a second surface of the core material facing the first surface, wherein the release layer contains a filler and has a portion in which the area ratio of the filler in the cross section of the release layer perpendicular to the first surface is 8.0% or more and 92% or less. [2] The electronic component temporary fixing member of [1] has a portion in which the transmittance of the release layer for light with a wavelength of 380 nm perpendicular to the first surface is 60% or less. [3] The electronic component temporary fixing member of [1] or [2] wherein the content of the filler in the release layer is 10% by mass or more and 80% by mass or less. [4] The component for temporarily fixing electronic components as described in [1] or [2], wherein the release layer contains a resin of adhesive or bonding component, and the filler contains 10 to 300 parts by mass relative to 100 parts by mass (solids) of the resin. [5] The component for temporarily fixing electronic components as described in [1] or [2], wherein the particle size (D50) of the filler, which has a cumulative volume percentage of 50%, is 0.1 μm to 20 μm. [6] The component for temporarily fixing electronic components as described in [1] or [2], wherein the filler contains silicon oxide. [7] The component for temporarily fixing electronic components as described in [1] or [2], wherein the 5% weight reduction temperature of the release layer is 250°C or higher. [8] The component for temporarily fixing electronic components as described in [1] or [2], wherein the 5% weight reduction temperature of the component for temporarily fixing electronic components is 250°C or higher. [9] The component for temporarily fixing electronic components as in [1] or [2], wherein the core material is composed of polyimide resin or epoxy resin.

[10] The component for temporarily fixing electronic components as in [1] or [2], wherein the thickness of the release layer is more than 1.2 times the particle size (D90) of the filler with a cumulative volume percentage of 90 vol%.

[11] The component for temporarily fixing electronic components as in [1] or [2] is in the form of an adhesive tape.

[0010] The electronic component temporary fixing member of the present invention has a laminated structure comprising: a release layer, a core material disposed on the release layer, and an adhesive layer disposed on the core material and separating the core material from the release layer. A support is attached to the release layer of the electronic component temporary fixing member. Therefore, the support is attached to the release layer in a state separating the release layer from the core material. Furthermore, a substrate on which electronic components are mounted is formed on the adhesive layer of the electronic component temporary fixing member.

[0011] In this invention, the term "area ratio of filler" refers to the proportion of the filler area in the aforementioned cross-section relative to the total area of ​​the peeling layer in the direction perpendicular to the first surface of the core material, that is, the total area of ​​the cross-section in the thickness direction of the peeling layer. [Effects of the Invention]

[0012] According to the embodiment of the electronic component temporary fixing member of the present invention, in the portion where the area ratio of the filler in the cross-section perpendicular to the first surface of the aforementioned release layer is 8.0% to 92%, when the support is peeled off from the electronic component temporary fixing member, the residue of the electronic component temporary fixing member on the support can be reduced. That is, in the embodiment of the electronic component temporary fixing member of the present invention, the support can be peeled off at the interface between the support and the release layer of the electronic component temporary fixing member, thereby improving the peeling performance of the release layer on the support. Therefore, according to the embodiment of the electronic component temporary fixing member of the present invention, a cleaning step to remove residue of the release layer on the support is not required, or a solvent is not required in the cleaning step, thus simplifying the cleaning step and facilitating the reuse of the support.

[0013] Furthermore, according to the form of the electronic component temporary fixing component of the present invention, since there is no need for a cleaning step to remove the residue of the peeling layer on the support or to simplify it, the manufacturing process of the substrate on which the electronic component is mounted can be prevented from becoming complicated, and the environmental burden can be prevented from increasing.

[0014] According to the configuration of the electronic component temporary fixing member of the present invention, by having the aforementioned release layer with a transmittance of less than 60% for light with a wavelength of 380nm in the direction perpendicular to the aforementioned first surface, when the support is peeled off from the electronic component temporary fixing member, the residue of the electronic component temporary fixing member on the support can be further reduced, thereby improving the peeling performance of the release layer on the support.

[0015] According to the configuration of the electronic component temporary fixing member of the present invention, by making the content of the aforementioned filler in the aforementioned release layer 10% by mass or more and 80% by mass or less, when the support is peeled off from the electronic component temporary fixing member, the residue of the electronic component temporary fixing member on the support can be reduced more effectively, thereby improving the peeling performance of the release layer on the support.

[0016] According to the configuration of the electronic component temporary fixing member of the present invention, by making the resin containing the aforementioned release layer contain an adhesive component or bonding component, and the aforementioned filler contains 10 to 300 parts by mass relative to 100 parts by mass (solids) of the aforementioned resin, when the support is peeled off from the electronic component temporary fixing member, the residue of the electronic component temporary fixing member on the support can be reduced more reliably, thereby improving the peeling performance of the release layer on the support.

[0017] According to the configuration of the electronic component temporary fixing component of the present invention, by making the particle size (D50) of the aforementioned filler with a cumulative volume percentage of 50% 0.1 μm or more and 20 μm or less, since the filler dispersion state in the release layer is uniform, the residue of the electronic component temporary fixing component on the support can be effectively reduced, and the release layer's peeling performance on the support can be effectively improved.

[0018] According to the form of the electronic component temporary fixing component of the present invention, by making the aforementioned filler contain silicon oxide, the residue of the electronic component temporary fixing component on the support can be effectively reduced, and the peeling performance of the release layer on the support can be effectively improved.

[0019] According to the configuration of the electronic component temporary fixing member of the present invention, by reducing the weight of the aforementioned release layer by 5% at a temperature of 250°C or higher, the release layer's peeling performance to the support is obtained, while simultaneously improving the heat resistance of the release layer. Therefore, in the process of forming the rewiring layer, etc., in order to harden the core material, there are cases where the electronic component temporary fixing member is exposed to a high temperature of 250°C or higher for a long time. Even if the electronic component temporary fixing member is exposed to a high temperature environment for a long time, the peeling performance of the release layer to the support can be maintained.

[0020] According to the configuration of the electronic component temporary fixing member of the present invention, by reducing the weight of the aforementioned electronic component temporary fixing member by 5% at a temperature of 250°C or higher, the peeling performance of the release layer to the support is obtained, and the heat resistance of the electronic component temporary fixing member including the release layer is improved. Therefore, even if the electronic component temporary fixing member is exposed to a high-temperature environment for a long time, the peeling performance of the release layer to the support can be maintained.

[0021] According to the present invention, the heat resistance of the core material is improved by making the core material composed of polyimide resin or epoxy resin, so that the temporary fixing component for electronic components can maintain its peeling performance from the support even when the temporary fixing component for electronic components is exposed to a high temperature environment for a long time.

[0022] According to the configuration of the electronic component temporary fixing component of the present invention, by making the thickness of the aforementioned release layer more than 1.2 times the particle size (D90) of the aforementioned filler with a cumulative volume percentage of 90% of the particle size, the adhesion and bonding of the release layer to the support can be maintained, and the dispersion state of the filler in the release layer can be stabilized. Therefore, the residue of the electronic component temporary fixing component on the support can be effectively reduced, and the release layer's peeling performance to the support can be effectively improved.

[0023] According to the present invention, the shape of the temporary fixing component for electronic components is made into a tape shape, which can improve the dimensional accuracy in the thickness direction of the temporary fixing component for electronic components. Furthermore, according to the present invention, the shape of the temporary fixing component for electronic components is made into a tape shape, and when the temporary fixing component for electronic components is formed by a coating method such as spin coating, since no solvent is required, it can prevent an increase in environmental impact.

Implementation Method

[0024] Hereinafter, the electronic component temporary fixing component of the present invention will be described in detail. The electronic component temporary fixing component of the present invention is used to temporarily fix electronic components when forming a substrate on which electronic components such as semiconductors are mounted.

[0025] <Construction of a Temporary Fixing Component for Electronic Components> The temporary fixing component for electronic components of the present invention comprises a release layer, a core material disposed on the release layer, and an adhesive layer disposed on the core material and separating the core material from the release layer. The core material is, for example, in a layered shape. That is, the temporary fixing component for electronic components of the present invention has a structure in which the release layer, the core material, and the adhesive layer are sequentially stacked.

[0026] Specifically, the core material, which is in a layered shape, has a first surface forming a main surface and a second surface forming a main surface facing the first surface. The electronic component temporary fixing member of the present invention has a laminated structure, which includes a core material, a release layer provided on the first surface of the core material, and an adhesive layer provided on the second surface of the core material facing the first surface. Based on the above, the release layer separates the core material from the adhesive layer.

[0027] The electronic component temporary fixing component of the present invention may be a three-layer structure consisting of a release layer, a core material, and an adhesive layer, or it may be a laminated structure having other layers besides the release layer, core material, and adhesive layer. In the case of a three-layer structure consisting of a release layer, a core material, and an adhesive layer, no other layer is disposed between the release layer and the core material, and the release layer is in contact with the core material; and no other layer is disposed between the core material and the adhesive layer, and the core material is in contact with the adhesive layer.

[0028] <Release Layer of Temporary Fixing Material for Electronic Components> The release layer of the temporary fixing component for electronic components of the present invention is the part to which the support body is adhered. The support body is adhered to the underside of the release layer in a state facing the first surface of the core material. The support body has the function of supporting the substrate of electronic components such as semiconductors, such as RDL layers, formed on the adhesive layer of the temporary fixing component for electronic components, on the underside of the release layer of the temporary fixing component for electronic components. Therefore, the support body is adhered to the release layer in a state facing the core material and the adhesive layer. After the substrate of electronic components such as semiconductors, such as RDL layers, is formed on the adhesive layer, the temporary fixing component is irradiated with laser light (wavelength, for example, 250nm~400nm) from the support body side through the support body, thereby separating the support body from the temporary fixing component for electronic components.

[0029] The release layer of the electronic component temporary fixing component of the present invention contains an adhesive with bonding components or an adhesive with adhesive components, and a filler with additives. By containing an adhesive with bonding components or an adhesive with adhesive components in the release layer, the support is bonded or adhered to the release layer. Furthermore, if necessary, the release layer may contain additives other than fillers such as fillers such as silane coupling agents.

[0030] Examples of adhesive components (main components) include epoxy resin, bismaleimide resin, etc. These resins can be used alone or in combination.

[0031] The epoxy resin is not particularly limited, and examples include phenolic varnish type epoxy resin, o-cresol phenolic varnish type epoxy resin, cresol phenolic varnish type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, biphenyl aryl type epoxy resin, phenyl aryl type epoxy resin, fluorene bisphenol type epoxy resin, triazine type epoxy resin, naphthol type epoxy resin, naphthalene glycol type epoxy resin, triphenylmethane type epoxy resin, tetraphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD ​​type epoxy resin, bisphenol S type epoxy resin, trimethylolpropane type epoxy resin, etc.

[0032] The epoxy equivalent of the epoxy resin is not particularly limited and can be appropriately selected according to the usage conditions, for example, 150 g / eq or higher and 450 g / eq or lower. Furthermore, the mass average molecular weight of the epoxy resin is not particularly limited and can be appropriately selected according to the usage conditions, for example, preferably 300 or higher and 10,000 or lower, and particularly preferably 500 or higher and 5,000 or lower. The aforementioned "mass average molecular weight" refers to the mass average molecular weight calculated by measuring the molecular weight using a gel permeation chromatography (GPC) instrument at room temperature and converting it to polystyrene.

[0033] Furthermore, the adhesive may contain phenoxy resins, (meth)acrylic resins, carbamate resins, etc., as needed. Phenoxy resins can be obtained by reacting bisphenol or biphenol compounds with epichlorohydrin, or by reacting liquid epoxy resins with bisphenol or biphenol compounds. Examples of bisphenol or biphenol compounds include, for example, bisphenol A, bisphenol AD, bisphenol AP, bisphenol AF, bisphenol B, bisphenol BP, bisphenol C, bisphenol E, bisphenol F, bisphenol G, bisphenol M, bisphenol S, bisphenol P, bisphenol PH, bisphenol TMC, and bisphenol Z; and 4,4'-biphenol, 2,2'-dimethyl-4,4'-biphenol, 2,2',6,6'-tetramethyl-4,4'-biphenol, and cardo skeletal bisphenols. Examples of liquid epoxy resins include diglycidyl ethers of aliphatic diol compounds. Examples of aliphatic diol compounds that are diglycidyl ethers include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-heptanediol, 1,6-hexanediol, 1,7-pentanediol, and 1,8-octanediol.

[0034] The epoxy equivalent of the phenoxy resin is not particularly limited and can be appropriately selected according to the usage conditions, for example, 5000 g / eq or more and 100000 g / eq or less. Furthermore, the mass average molecular weight of the phenoxy resin is not particularly limited and can be appropriately selected according to the usage conditions, for example, preferably 10000 or more and 200000 or less, and particularly preferably 20000 or more and 100000 or less.

[0035] An epoxy resin curing agent may be added to the adhesive as a curing agent as needed. Examples of epoxy resin curing agents include amines, acid anhydrides, and polyphenols. In the temporary fixing component for electronic parts of the present invention, based on the viewpoint of having a low melt viscosity, high-temperature curing properties, rapid curing properties, and high storage stability that allows for long-term storage at room temperature, a latent curing agent is preferred. Examples of latent curing agents include dicyandiamide compounds, imidazole compounds, curing catalyst complex polyphenol compounds, acehydrazine compounds, boron trifluoride-amine complexes, aceamine-aceimine compounds, polyamine salts, and modified or microencapsulated forms of these compounds. These epoxy resin curing agents may be used alone or in combination of two or more.

[0036] The content of epoxy resin hardener is not particularly limited, but based on the viewpoint of shortening the curing time of the adhesive component (main component) of the adhesive, its lower limit is preferably 0.5 parts by weight, more preferably 1.0 parts by weight, and particularly preferably 1.5 parts by weight relative to 100 parts by weight of the adhesive component (main component) of the adhesive. On the other hand, the upper limit of the content of epoxy resin hardener is based on the viewpoint of preventing the adhesive reliability from decreasing due to epoxy resin hardener residue in the adhesive and adsorbing moisture, and is preferably 7.0 parts by weight, more preferably 5.0 parts by weight, and particularly preferably 4.0 parts by weight relative to 100 parts by weight of the adhesive component (main component) of the adhesive.

[0037] The adhesive has the function of imparting adhesion to the core material to the release layer. On the other hand, in order to peel the support off at the interface between the release layer of the support and the component for temporary fixation of the electronic parts, it is preferable that the adhesion to the support is lower than the adhesion to the core material, that is, the peelability to the support is higher than the peelability to the core material. Examples of adhesive components (main components) as adhesives include, for example, (meth)acrylic resin, silicone, and urethane resin.

[0038] Examples of (meth)acrylic resins include resins made from (meth)acrylic (co)polymers (co)polymers of (meth)acrylic monomers. Examples of (meth)acrylic resins include poly(meth)acrylates or their derivatives. Examples of (meth)acrylic monomer components constituting (meth)acrylic resins include carboxylic acids containing vinyl unsaturated groups, such as acrylic acid, methacrylic acid, itaconic acid, etc.; (meth)acrylates having hydroxyl groups, such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, etc.; and (meth)acrylates having epoxy groups, such as glycidyl methacrylate, glycidyl acrylate, etc. Furthermore, examples of monomeric components constituting (meth)acrylate resins include (meth)acrylates with a cyclic skeleton, such as cycloalkyl (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentenoxyethyl (meth)acrylate; imidin (meth)acrylates; and alkyl (meth)acrylates with an alkyl group having 1 to 18 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and butyl (meth)acrylate. These (meth)acrylate monomeric components can be used alone or in combination of two or more.

[0039] In addition to the above-mentioned (meth)acrylic acid monomers, (meth)acrylic resins can also be copolymerized with other monomers such as vinyl acetate, (meth)acrylonitrile, and styrene.

[0040] The average molecular weight of (meth)acrylic resin is not particularly limited and can be appropriately selected according to the usage conditions, for example, preferably 10,000 or more and 2,000,000 or less, and particularly preferably 100,000 or more and 1,500,000 or less.

[0041] When using (meth)acrylic resin as the adhesive component, additives such as (meth)acrylic resin curing agents and isocyanate compounds can be formulated as needed. Furthermore, by formulating (meth)acrylic resin curing agents and isocyanate compounds, the adhesive strength of the adhesive can be appropriately adjusted according to the usage conditions of the components used for temporary fixing of electronic parts. Examples of (meth)acrylic resin curing agents include multifunctional epoxy resins such as 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane and N,N,N',N'-tetraglycidyl-m-xylenediamine.

[0042] The content of the (meth)acrylic resin hardener is not particularly limited, as long as the adhesive strength can be adjusted to the required range according to the usage conditions of the component for temporary fixing of electronic parts. For example, the lower limit is preferably 0.1 parts by weight, more preferably 0.2 parts by weight, and particularly preferably 0.3 parts by weight, relative to 100 parts by weight of the adhesive component (main component). On the other hand, the upper limit of the (meth)acrylic resin hardener content is preferably 3.0 parts by weight, more preferably 2.0 parts by weight, and particularly preferably 1.0 parts by weight, relative to 100 parts by weight of the adhesive component (main component).

[0043] In the temporary fixing component for electronic components of the present invention, the release layer contains a filler. Furthermore, in the temporary fixing component for electronic components of the present invention, the filler content is adjusted such that the area ratio of the filler in the cross-section perpendicular to the first surface of the core material of the release layer is 8.0% to 92%. That is, the filler content is adjusted such that the area ratio of the filler in the cross-section of the release layer in terms of its thickness is 8.0% to 92%.

[0044] In the temporary fixing member for electronic components of the present invention, by including a filler in the release layer, the release layer is made to have the absorption property of laser light with a wavelength of 250nm to 400nm. Furthermore, by having a portion in the release layer where the area ratio of the filler in the cross-section of the release layer in terms of thickness is 8.0% to 92%, laser light with a wavelength of 250nm to 400nm is irradiated from the support side of the support body toward the temporary fixing member for electronic components of the present invention. The release layer absorbs the laser light, causing the release layer to decompose. As a result, at the interface between the support body and the release layer, the support body is peeled off from the temporary fixing member for electronic components. Moreover, when peeling the support body from the temporary fixing member for electronic components of the present invention, the residue of the temporary fixing member for electronic components on the support body can be reduced. That is, the support body can be easily peeled off at the interface between the support body and the release layer of the temporary fixing member for electronic components, and the peeling performance of the release layer on the support body is improved. Therefore, in the electronic component temporary fixing component of the present invention, there is no need for a cleaning step to remove the peeling layer residue on the support, or there is no need to use a solvent in the cleaning step, which simplifies the cleaning step and makes the support easy to reuse.

[0045] Furthermore, since the electronic component temporary fixing component of the present invention does not require a cleaning step to remove the peeling layer residue on the support or can simplify the cleaning step, it can prevent the manufacturing process of the substrate on which the electronic component is mounted from becoming complicated and can prevent an increase in environmental impact.

[0046] The release layer may have at least a portion of a region in which the filler area ratio in the thickness direction of the release layer is 8.0% or more and 92% or less. However, based on the viewpoint of effectively improving the release performance of the release layer to the support, the filler area ratio in the thickness direction of the release layer is preferably 8.0% or more and 92% or less in the entire release layer.

[0047] Furthermore, the area ratio of the filler in the thickness direction of the release layer is not particularly limited as long as it is in the range of 8.0% to 92%, but the lower limit is preferably 9.0%, and more preferably 10%, based on the viewpoint of further improving the release performance of the release layer to the support. On the other hand, the upper limit of the area ratio of the filler in the thickness direction of the release layer is preferably 70%, more preferably 60%, and more preferably 55%, based on the viewpoint of ensuring the adhesion and bonding properties of the release layer.

[0048] The transmittance of the release layer for light with a wavelength of 380 nm in the direction perpendicular to the first surface of the core material is not particularly limited. However, based on the view that when the support is peeled from the electronic component temporary fixing component, the residue of the electronic component temporary fixing component on the support can be reduced more effectively, and the peeling performance of the release layer to the support can be improved, it is preferable that the portion having the aforementioned light transmittance is 60% or less, more preferably that the aforementioned light transmittance of the entire release layer is 60% or less, and particularly preferably that the aforementioned light transmittance of the entire release layer is 55% or less. The aforementioned light transmittance can be adjusted by adjusting the filler content. By adjusting the filler content so that the filler area ratio in the cross-section of the thickness direction of the release layer is in the range of 8.0% to 92%, the transmittance can be easily adjusted to 60% or less. Furthermore, the lower limit of the transmittance of the release layer to light with a wavelength of 380 nm in the direction perpendicular to the first surface of the core material is preferably 0%, based on the viewpoint of reliably imparting adhesion and bonding of the release layer to the support.

[0049] The content of filler in the release layer is not particularly limited as long as the area ratio of filler in the cross section along the thickness direction of the release layer is in the range of 8.0% to 92%. However, the lower limit is preferably 10% by mass, more preferably 13% by mass, and particularly preferably 20% by mass, based on the view that when the support is peeled from the electronic component temporary fixing component, the residue of the electronic component temporary fixing component on the support can be reduced more effectively, and the peeling performance of the release layer to the support can be improved. On the other hand, based on the view that the adhesion and bonding properties of the release layer can be obtained, the upper limit of the filler content in the release layer is preferably 80% by mass, more preferably 75% by mass, and particularly preferably 70% by mass.

[0050] In the release layer of the resin containing adhesive or bonding components, the content of filler relative to 100 parts by weight (solids) of the aforementioned resin is not particularly limited, as long as the filler area ratio in the cross section along the thickness direction of the release layer is between 8.0% and 92%. However, the lower limit is preferably 10 parts by weight, more preferably 15 parts by weight, and particularly preferably 30 parts by weight, relative to 100 parts by weight (solids) of the aforementioned resin, based on the view that when the support is peeled from the electronic component temporary fixing component, the residue of the electronic component temporary fixing component on the support can be more effectively reduced, and the peeling performance of the release layer to the support can be further improved. On the other hand, the upper limit of filler relative to 100 parts by weight (solids) of the aforementioned resin is preferably 300 parts by weight, more preferably 250 parts by weight, and particularly preferably 200 parts by weight, based on the view that the adhesion and tack of the release layer can be effectively obtained.

[0051] The filler is a particulate component, and the shape of the filler is, for example, spherical. The particle size (D50) of the filler with a cumulative volume percentage of 50% is not particularly limited, but based on the view that the uniformity of the dispersion state of the filler in the release layer can effectively reduce the residue of the electronic component temporary fixing component on the support and effectively improve the release performance of the release layer to the support, it is preferred to be 0.1 μm or more and 20 μm or less, and particularly preferred to be 0.5 μm or more and 10 μm or less.

[0052] The particle size (D90) of the filler with a cumulative volume percentage of 90% is not particularly limited, but based on the view that the uniform dispersion of the filler in the release layer can effectively reduce the residue of the electronic component temporary fixing component on the support and effectively improve the release performance of the release layer to the support, it is preferably 1.0 μm or more and 35 μm or less, and particularly preferably 2.0 μm or more and 25 μm or less. Furthermore, the particle size (D10) of the filler with a cumulative volume percentage of 10% is not particularly limited, but based on the view that the uniform dispersion of the filler in the release layer can effectively reduce the residue of the electronic component temporary fixing component on the support and effectively improve the release performance of the release layer to the support, it is preferably 0.03 μm or more and 5.0 μm or less, and particularly preferably 0.05 μm or more and 3.0 μm or less.

[0053] The relationship between the particle size of the filler and the thickness of the release layer is not particularly limited. However, from the viewpoint that the adhesion and bonding of the release layer to the support can be compromised, and the dispersion state of the filler in the release layer can be stabilized, the residue of the temporary fixing components for electronic parts on the support can be effectively reduced, and the release layer's release performance to the support can be effectively improved, the thickness of the release layer is preferably 1.2 times or more, more preferably 1.5 times or more, and particularly preferably 2.0 times or more, of the particle size (D90) at which the cumulative volume percentage of the filler is 90% by volume. Furthermore, from the viewpoint of effectively obtaining the release layer's release performance to the support, the thickness of the release layer is preferably 10 times or less, and particularly preferably 5.0 times or less, of the particle size (D90) at which the cumulative volume percentage of the filler is 90% by volume. Also, D10, D50, and D90 of the filler refer to the particle size measured using a particle size distribution measuring device using a laser diffraction / scattering method.

[0054] Examples of fillers include inorganic fillers. Examples of inorganic fillers include ceramics such as silicon oxide, clay, gypsum, calcium carbonate, barium sulfate, alumina, beryllium oxide, magnesium oxide, silicon carbide, silicon nitride, aluminum nitride, and boron nitride; metals such as aluminum, copper, silver, gold, nickel, chromium, tin, zinc, palladium, and solder; and carbon-based inorganic powders such as carbon nanotubes and graphene. Among these, based on the view that the excellent absorption characteristics of laser light with wavelengths of 250nm to 400nm can effectively reduce the residue of components used for temporarily fixing electronic parts on the support and effectively improve the peeling performance of the release layer on the support, it is preferable to include silicon oxide, alumina, silver, and copper as fillers.

[0055] In the temporary fixing component for electronic parts of the present invention, a silane coupling agent may also be incorporated into the release layer as needed. By incorporating a silane coupling agent into the release layer, the dispersibility of the filler in the adhesive and bonding components can be improved. Specifically, when epoxy resin is used as the adhesive component, an epoxy silane coupling agent may be incorporated, and when (meth)acrylic resin is used as the bonding component, a (meth)acrylic silane coupling agent may be incorporated. The epoxy silane coupling agent is a silane coupling agent having an epoxy group as an organic functional group. The (meth)acrylic silane coupling agent is a silane coupling agent having a (meth)acrylic group as an organic functional group.

[0056] Examples of silane coupling agents include, for example, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane. Alkane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-methylpropenoxypropylmethyldimethoxysilane, 3-methylpropenoxypropyltrimethoxysilane, 3-methylpropenoxypropylmethyldiethoxysilane, 3-methylpropenoxypropyltriethoxysilane, etc.

[0057] The content of the silane coupling agent is not particularly limited. For example, based on the viewpoint of effectively improving the dispersibility of the filler and suppressing the occurrence of gas release, it is preferably 0.1 parts by mass or more and 5.0 parts by mass or less, and particularly preferably 0.3 parts by mass or more and 3.0 parts by mass or less, relative to 100 parts by mass of the filler.

[0058] The 5% weight reduction temperature of the release layer is not particularly limited, but from the viewpoint of obtaining the release layer's peel performance from the support and improving the heat resistance of the release layer, it is preferably 250°C or higher, more preferably 300°C or higher, and especially preferably 330°C or higher. In the formation steps of the rewiring layer, etc., in order to harden the core material, the components for temporarily fixing electronic components are sometimes exposed to high temperatures of 250°C or higher for a long time. By improving the heat resistance of the release layer, even if the components for temporarily fixing electronic components are exposed to high temperature environments for a long time, the peel performance of the release layer from the support can be maintained. An example of an upper limit for the 5% weight reduction temperature of the release layer is 500°C.

[0059] The so-called "5% weight reduction temperature" refers to the temperature at which the mass of the sample being evaluated decreases by 5% relative to the mass before heating when the sample is heated. It is measured using a differential thermal analysis device under the following conditions: heating temperature 10℃ / min, nitrogen environment, and flow rate 50ml / min.

[0060] The thickness of the release layer is not particularly limited and can be appropriately selected according to the usage conditions of the component for temporary fixation of electronic parts, for example, 3μm or more and 100μm or less.

[0061] <Core Material of Electronic Component Temporary Fixing Component> The core material of the electronic component temporary fixing component of the present invention is a substrate that has the function of maintaining the shape of the electronic component temporary fixing component, while supporting the release layer by the first surface of the core material and supporting the adhesive layer described later by the second surface of the core material.

[0062] The material of the core material is not particularly limited, but examples include resins with amide bonds such as polyimide resins, polyesters such as polyethylene terephthalate and polyethylene naphthalate, epoxy resins, and phenoxy resins. From the viewpoint of improving the heat resistance of the core material so that even if the electronic component temporary fixing component is exposed to a high-temperature environment for a long time, it can still maintain the peel performance of the electronic component temporary fixing component to the support, the core material is preferably made of a heat-resistant component, such as polyethylene terephthalate, polyimide resins, or epoxy resins. From the viewpoint of further improving heat resistance, it is particularly preferred to make it of polyimide resins or epoxy resins.

[0063] The first and second surfaces of the core material can be surface modified by corona treatment or the like as needed. By surface modification by corona treatment or the like, the adhesion of the first surface to the release layer is improved, and the adhesion of the second surface to the adhesive layer is enhanced.

[0064] The core material may be in the form of, for example, layers, sheets, or strips. The thickness of the core material is not particularly limited and may be appropriately selected according to the usage conditions of the component for temporary fixing of electronic parts, for example, 5μm or more and 100μm or less.

[0065] <Adhesive Layer for Temporary Fixing of Electronic Components> The adhesive layer of the temporary fixing component for electronic components of the present invention is used to process the semiconductor substrate or the like of the workpiece at the bonding portion of the workpiece, forming a substrate on which the desired electronic components are mounted. After the substrate on which the desired electronic components are mounted is formed, the substrate on which the electronic components are mounted can be removed from the temporary fixing component by peeling the substrate formed from the adhesive layer.

[0066] Examples of adhesive components (main components) for the adhesive layer include (meth)acrylic acid polymers, silicone, and urethane resins. Examples of components constituting the (meth)acrylic acid polymer include (meth)acrylate components, (meth)acrylic acid components, (meth)acrylamide components, and (meth)acrylonitrile components. Among these, it is preferable that the (meth)acrylic acid polymer contains (meth)acrylate components. The (meth)acrylic acid polymer preferably contains 50% by mass or more of (meth)acrylate components, more preferably 70% by mass or more, and particularly preferably 80% by mass or more.

[0067] Examples of monomers used as the (meth)acrylate component of the derived (meth)acrylate polymer include, for example, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, isobutyl methacrylate, dibutyl methacrylate, terbutyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, isooctyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, isononyl methacrylate, and so on. (Meth)acrylates such as decyl methacrylate, isodecyl methacrylate, undecyl methacrylate, dodecyl methacrylate, tridecyl methacrylate, tetradecyl methacrylate, pentadecyl methacrylate, hexadecyl methacrylate, heptadecanyl methacrylate, octadecyl methacrylate, etc.; (Meth)acrylates such as cyclohexyl methacrylate; (Meth)acrylates such as phenyl methacrylate; (Meth)acrylates containing hydroxyl groups such as 2-hydroxyethyl methacrylate and 2-hydroxypropyl methacrylate. These compounds can be used alone or in combination of two or more.

[0068] In the adhesive layer, additives such as (meth)acrylic resin curing agents and isocyanate compounds may also be formulated as needed. Furthermore, by formulating (meth)acrylic resin curing agents and isocyanate compounds, the adhesive layer can be imparted with high-temperature curing properties and rapid curing properties. Examples of (meth)acrylic resin curing agents include multifunctional epoxy resins such as 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane and N,N,N',N'-tetraglycidyl-m-xylenediamine.

[0069] The content of the (meth)acrylic resin hardener is not particularly limited. Its lower limit, based on the viewpoint of shortening the curing time of the (meth)acrylic polymer, is preferably 0.1 parts by weight, more preferably 0.2 parts by weight, and particularly preferably 0.3 parts by weight relative to 100 parts by weight of the (meth)acrylic polymer. On the other hand, the upper limit of the content of the (meth)acrylic resin hardener is preferably 3.0 parts by weight, more preferably 2.0 parts by weight, and particularly preferably 1.0 parts by weight relative to 100 parts by weight of the (meth)acrylic polymer.

[0070] The thickness of the adhesive layer is not particularly limited and can be appropriately selected according to the usage conditions of the component for temporary fixing of electronic parts, for example, 5μm or more and 100μm or less.

[0071] <Characteristics of the entire temporary mounting component for electronic components> The 5% weight reduction temperature of the temporary mounting component for electronic components is not particularly limited, but based on the viewpoint of obtaining the peeling performance of the release layer to the support and improving the overall heat resistance of the temporary mounting component for electronic components including the release layer, it is preferable to be 250°C or higher, more preferably 300°C or higher, and particularly preferably 330°C or higher. In the forming steps of the rewiring layer, etc., in order to harden the core material, there are cases where the temporary mounting component for electronic components is exposed to high temperatures of 250°C or higher for a long time. Because the overall heat resistance of the temporary mounting component for electronic components is improved, even if the temporary mounting component for electronic components is exposed to a high-temperature environment for a long time, the peeling performance of the release layer to the support can be maintained. An example of an upper limit for the 5% weight reduction temperature of the temporary mounting component for electronic components is 500°C.

[0072] The shape of the temporary fixing component for electronic components can be appropriately selected according to the usage conditions of the temporary fixing component for electronic components, for example, in the form of a strip or a sheet. Because the shape of the temporary fixing component for electronic components is strip-shaped or sheet-shaped, the dimensional accuracy in the thickness direction of the temporary fixing component for electronic components can be improved. Furthermore, because the shape of the temporary fixing component for electronic components of the present invention is strip-shaped or sheet-shaped, when the temporary fixing component for electronic components is formed by a coating method such as spin coating, no solvent is required, thus preventing an increase in environmental impact.

[0073] The temporary mounting component for electronic components can be preserved for a long time by attaching cover spacers to the outer surfaces of the release layer and the adhesive layer, respectively. When using the temporary mounting component for electronic components, the cover spacers attached to the outside of the release layer are removed and attached to a support, and the cover spacers attached to the outside of the adhesive layer are removed and attached to a semiconductor substrate or similar object being processed. [Example]

[0074] Next, embodiments of the present invention will be described, but the present invention is not limited to these embodiments as long as it does not go beyond its spirit.

[0075] [Fabrication of Components for Temporary Fixation of Electronic Parts] [Example 1] Fabrication of the release layer: 50 parts by weight of liquid epoxy resin (trade name: YD-128, bisphenol A type epoxy resin, average molecular weight: 400, epoxy equivalent: 190, Nippon Steel Chemical & Materials Co., Ltd.), 20 parts by weight of solid epoxy resin (trade name: EPPN-501H, triphenylmethane type epoxy resin, average molecular weight: 1000, epoxy equivalent: 167, Nippon Chemical Co., Ltd.), and 30 parts by weight of phenoxy resin (trade name: YP-50, bisphenol A type phenoxy resin, average molecular weight: 70000, Nippon Steel Chemical & Materials Co., Ltd.) were heated and stirred at 100°C for 2 hours in a 1000ml separable flask with methyl ethyl ketone (MEK) to obtain a resin varnish. Next, the obtained resin varnish was transferred to an 800ml planetary mixer, and 70 parts by weight of particulate silica filler (trade name: FB-5SDX, D10: 1.1μm, D50: 4.2μm, D90: 9.5μm, specific surface area: 2.7m2 / g, Denka Co., Ltd.) as filler were added, along with 3 parts by weight of imidazole type curing agent (trade name: 2PHZ-PW, epoxy resin curing agent, Shikoku Kasei Co., Ltd.) and 0.35 parts by weight of epoxy silane coupling agent (trade name: KBM-403, 3-glycidoxypropyltrimethoxysilane, Shin-Etsu Silicon Oxide Co., Ltd.). After stirring and mixing at room temperature for 1 hour, vacuum degassing was performed to obtain the mixed varnish. Next, the obtained mixed varnish is applied to the first side of a 25μm thick polyimide film of the core material, and then heated and dried at 130°C for 5 minutes to obtain a release layer film with a thickness of 20μm on one side (first side) of the core material.

[0076] Furthermore, at this time, as an evaluation of the parallel line transmittance (wavelength of light 380nm) of the release layer, the mixed varnish of the release layer obtained as described above is applied to a PET film (release film) with a thickness of 38μm that has undergone demolding treatment, and then heated and dried at 135°C for 5 minutes. A sample for evaluating the parallel line transmittance of the release layer with the release film attached is also prepared at the same time.

[0077] The adhesive layer was prepared in a reaction vessel equipped with a cooling pipe, a nitrogen inlet pipe, a thermometer, and a stirring device. 100 parts by weight of 2-ethylhexyl acrylate (HA), 8 parts by weight of 2-hydroxyethyl acrylate, 0.3 parts by weight of azobisisobutyronitrile (AIB), and 60 parts by weight of ethyl acetate were added. The mixture was polymerized at 65°C for 6 hours under a nitrogen atmosphere to obtain an acrylic polymer solution. 0.5 parts by weight of an epoxy compound (trade name: Tetrad C, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, Mitsubishi Gas Chemical Co., Ltd.) was added to 100 parts by weight of the acrylic polymer as an acrylic resin curing agent (crosslinking agent) to prepare an adhesive solution. The obtained adhesive solution was coated onto a PET film (release film) that had undergone demolding treatment and dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 20 μm.

[0078] Fabrication of the temporary fixing component for electronic components: The adhesive layer on the obtained release film is transferred onto the opposite side (second side) of the core material and the release layer to obtain the temporary fixing component for electronic components of Example 1.

[0079] [Example 2] Except that the amount of silica filler added to the release layer was set to 15 parts by mass and the amount of epoxy silane coupling agent added was set to 0.075 parts by mass, the electronic component temporary fixing component was obtained in the same manner as in Example 1.

[0080] [Example 3] Except that the amount of silica filler added to the release layer was set to 230 parts by mass and the amount of epoxy silane coupling agent added was set to 1.15 parts by mass, the electronic component temporary fixing component was obtained in the same manner as in Example 1.

[0081] [Example 4] In the preparation of the release layer, instead of using epoxy resin and phenoxy resin resin varnish, an acrylic resin varnish prepared as follows was used, and instead of epoxy resin hardener, 0.5 parts by weight of acrylic resin hardener (trade name: Tetrad C, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, Mitsubishi Gas Chemical Co., Ltd.) was added. The amount of silica filler added to the release layer was set to 140 parts by weight. Instead of epoxy silane coupling agent, 0.7 parts by weight of acrylic silane coupling agent (trade name: KBM-503, 3-methacryloxypropyltrimethoxysilane, Shin-Etsu Silicon Oxide Co., Ltd.) was added. Before the adhesive layer was prepared, a film with a release layer thickness of 20 μm was deposited on one side (first side) of the core material and left to stand at room temperature (25°C) for 1 week. In addition, a component for temporary fixation of electronic parts was obtained in the same way as in Example 1.

[0082] The acrylic resin varnish was prepared by placing 100 parts by weight of 2-ethylhexyl acrylate (HA), 8 parts by weight of 2-hydroxyethyl acrylate, 0.3 parts by weight of azobisisobutyronitrile, and 60 parts by weight of ethyl acetate into a reaction vessel equipped with a cooling pipe, a nitrogen inlet pipe, a thermometer, and a stirring device. The polymerization reaction was carried out at 65°C for 6 hours under a nitrogen flow to obtain a solution of acrylic polymer.

[0083] [Example 5] Except that the amount of silica filler added to the release layer was set to 90 parts by mass and the amount of epoxy silane coupling agent added was set to 0.45 parts by mass, the electronic component temporary fixing component was obtained in the same manner as in Example 4.

[0084] [Example 6] Except that the amount of silica filler added to the release layer was set to 200 parts by mass and the amount of silane coupling agent for acrylic acid added was set to 1.0 parts by mass, the component for temporary fixing of electronic parts was obtained in the same manner as in Example 4.

[0085] [Example 7] Except for the use of polyethylene terephthalate instead of polyimide film as the core material, a temporary fixing component for electronic parts was obtained in the same manner as in Example 1.

[0086] [Example 8] Except for the use of an epoxy resin film instead of a polyimide film for the core material, a temporary fixing component for electronic parts was obtained in the same manner as in Example 1.

[0087] The method for preparing the film made of epoxy resin is as follows. 50 parts by weight of epoxy resin (trade name: YD-128, bisphenol A type epoxy resin, mass average molecular weight: 400, epoxy equivalent: 190, Nippon Steel Chemical & Materials Co., Ltd.), 50 parts by weight of phenoxy resin (trade name: YP-50, bisphenol A type phenoxy resin, mass average molecular weight: 70000, Nippon Steel Chemical & Materials Co., Ltd.), and 1 part by weight of thermosetting agent (trade name: SI-300, hot acid generator, Sanshin Chemical Co., Ltd.) are dissolved in methyl ethyl ketone to obtain a composition containing epoxy compounds. The obtained composition containing epoxy compounds is coated using a corner-cutting wheel coater, dried at 130°C for 3 minutes, and then heated at 110°C for 3 hours to perform thermosetting treatment, obtaining a substrate film (25 μm).

[0088] [Comparative Example 1] Except that the release layer did not contain silica filler and epoxy silane coupling agent, the electronic component temporary fixing component was obtained in the same manner as in Example 1.

[0089] [Comparative Example 2] Except that the amount of silica filler added to the release layer was set to 5 parts by mass and the amount of epoxy silane coupling agent added was set to 0.025 parts by mass, the electronic component temporary fixing component was obtained in the same manner as in Example 1.

[0090] [Comparative Example 3] Except that the release layer did not contain silica filler and silane coupling agent for acrylic acid, the electronic component temporary fixing component was obtained in the same manner as in Example 4.

[0091] [Comparative Example 4] Except that the amount of silica filler added to the release layer was set to 8 parts by mass and the amount of silane coupling agent for acrylic acid added was set to 0.04 parts by mass, the electronic component temporary fixing component was obtained in the same manner as in Example 4.

[0092] [Comparative Example 5] Except that the amount of silica filler added to the release layer was set to 10 parts by mass, the amount of epoxy silane coupling agent added was set to 0.05 parts by mass, and polyethylene terephthalate was used instead of polyimide film for the core material, the electronic component temporary fixing component was obtained in the same manner as in Example 1.

[0093] The evaluation items for the temporary fixing components for electronic parts in the embodiments and comparative examples are as follows.

[0094] (1) Area ratio of filler in the thickness direction of the release layer (area ratio of filler in the release layer) (unit: %) The temporary electronic component fixing component of the examples and comparative examples was embedded in resin (Nichishin EM Co., Ltd., NER-814). The embedded temporary electronic component fixing component was mechanically ground to expose the thickness direction of the temporary electronic component fixing component. Subsequently, the exposed section was ion-trimmed using an ion trimming device (Hitachi High Technology Co., Ltd., IM4000II). Subsequently, a conductivity treatment was performed, and FE-SEM observation was performed. FE-SEM was performed with an accelerating voltage of 1kV~5kV, and the reflected electron image was observed. The captured image was binarized using the image analysis software Image-J to identify the filler. From the filler area of ​​the image, the filler area ratio in the thickness direction of the release layer was calculated using the following formula (A). The area ratio (%) of filler in the thickness direction of the release layer = area of ​​filler in the thickness direction of the release layer / cross-sectional area in the thickness direction of the release layer... Equation (A)

[0095] (2) Parallel line transmittance of the release layer (wavelength of light 380nm) After heating the release layer on the release film to 70°C and attaching it to the glass plate, the release film is peeled off to obtain a glass sample with the release layer attached. The transmittance of the glass plate is set as the baseline, and the parallel line transmittance of light at a wavelength of 380nm (transmittance in the thickness direction of the release layer) of the release layer is measured using a spectrophotometer (Hitachi High Technology Co., Ltd., Spectrophotometer U-4100 Solid Data Measurement System).

[0096] Furthermore, in Examples 1, 2, 3, 7, 8, and Comparative Examples 1, 2, and 5, the glass samples with the release layer were heated at 150°C for 1 hour, and the parallel line transmittance was measured. In Examples 4, 5, 6, and Comparative Examples 3 and 4, the glass samples with the release layer were not subjected to heating treatment, and the parallel line transmittance was measured immediately.

[0097] (3) 5% weight loss temperature: In Examples 1, 2, 3, 7, 8, and Comparative Examples 1, 2, and 5, after heating at 150°C for 1 hour, in Examples 4, 5, 6, and Comparative Examples 3 and 4, without heat treatment, 10 mg of samples (release layer, temporary fixing components for electronic parts) were measured and placed in an alumina sample tray. A differential thermal-thermogravimetric analyzer (trade name: TG / DTA320, Seiko Instruments Co., Ltd.) was used in a nitrogen atmosphere at a flow rate of 50 mL / min and a heating rate of 10°C / min, from room temperature to 500°C. The temperature at which the sample mass decreased by 5% (the temperature at which the sample mass became 9.5 mg) was set as the 5% weight loss temperature, and the following criteria were used for evaluation: ◎: 5% weight loss temperature ≥ 300°C. 〇: 5% weight loss temperature ≥ 250°C but less than 300°C. ×: 5% weight loss temperature less than 250°C.

[0098] (4) Laser stripping performance (LLO stripping performance) On a 5cm square quartz glass plate, the stripping layer side of the electronic component temporary fixing component was attached to the quartz glass and heated to 70°C. Subsequently, the glass plate was attached to the adhesive layer side of the electronic component temporary fixing component and hardened by heating at 150°C for 1 hour in Examples 1, 2, 3, 7, 8, and Comparative Examples 1, 2, and 5. Subsequently, laser stripping (LLO) was performed by irradiating the quartz glass surface with Nd-YAG laser. The LLO conditions were set as follows: wavelength 355nm, output 600mW, frequency 10kHz, and irradiation diameter 20μmφ. After LLO, the presence of peeling of the quartz glass at the interface between the quartz glass and the stripping layer and the presence of residue of the stripping layer in the quartz glass were observed visually and under a microscope and evaluated according to the following criteria. ◎: The quartz glass has peeled off at the interface between the quartz glass and the release layer, with no residue of the release layer remaining on the quartz glass. 〇: The quartz glass has peeled off at the interface between the quartz glass and the release layer, but some residue of the release layer remains on a portion of the quartz glass. ×: The quartz glass has not peeled off at the interface between the quartz glass and the release layer, and residue of the release layer remains on the entire surface of the quartz glass.

[0099] The components and evaluation results of the examples and comparative examples are shown in Table 1 below.

[0100]

[0101] As shown in Table 1 above, the electronic component temporary fixing components of Examples 1 to 8, in which the area ratio of filler in the cross section in the thickness direction of the release layer is 8.0% to 92%, have excellent LLO release performance, and the support is peeled off at the interface between the support and the release layer, and there is no residue of the release layer on the support.

[0102] Furthermore, as shown in Table 1 above, the electronic component temporary fixing components of Examples 1 to 8, in which the area ratio of filler in the cross section in the thickness direction of the release layer is 8.0% to 92%, have a parallel line transmittance of the release layer at a wavelength of 380nm of light of 60% or less, and excellent laser light absorption characteristics.

[0103] Furthermore, the electronic component temporary fixing components of Examples 1-8 not only have excellent LLO peel performance, but also have a high 5% weight reduction temperature of the release layer, and the release layer has excellent heat resistance. It is also known that the electronic component temporary fixing components of Examples 1-6 (using polyimide as the core material) and Example 8 (using epoxy resin as the core material) have excellent heat resistance because the entire electronic component temporary fixing component and the core material have a high 5% weight reduction temperature, and the entire electronic component temporary fixing component and the core material are exposed to high temperatures for a long time. Therefore, even if the heat-resistant electronic component temporary fixing component is exposed to a high-temperature environment for a long time, the peel performance of the release layer to the support can still be maintained.

[0104] In the electronic component temporary fixing components of Examples 1 to 8, the filler content in the release layer is adjusted to 13% by mass or more and 69% by mass or less.

[0105] On the other hand, as shown in Table 1 above, the electronic component temporary fixing components of Comparative Examples 1 to 5, in which the area ratio of filler in the cross section in the thickness direction of the release layer is less than 7%, cannot obtain excellent LLO release performance. The support cannot be successfully peeled off at the interface between the support and the release layer, and residue of the release layer remains on the support.

[0106] Furthermore, as shown in Table 1 above, the electronic component temporary fixing components of Comparative Examples 1 to 5, in which the area ratio of filler in the cross-section of the release layer in the thickness direction is 7% or less, have a parallel line transmittance of the release layer at a wavelength of 380 nm of light of 65% or more, and cannot obtain the absorption characteristics of laser light. Moreover, in Comparative Example 5, which uses polyethylene terephthalate as the core material, the 5% weight reduction of the electronic component temporary fixing component and the core material results in a low temperature, and poor heat resistance of the electronic component temporary fixing component and the core material.

Claims

1. A component for temporarily fixing electronic parts, having a 5% weight reduction temperature of 250°C or higher, and comprising: a core material, a release layer provided on a first surface of the core material, and an adhesive layer provided on a second surface of the core material facing the first surface, wherein the release layer contains a filler and has a portion in which the area ratio of the filler in the cross-section of the release layer perpendicular to the first surface is 8.0% or more and 92% or less.

2. The component for temporary fixing of electronic parts as claimed in claim 1, wherein the portion of the aforementioned release layer has a transmittance of less than 60% for light with a wavelength of 380 nm in the direction perpendicular to the aforementioned first surface.

3. For the temporary fixing component of electronic parts as requested in item 1 or 2, wherein the content of the aforementioned filler in the aforementioned release layer is more than 10% by mass and less than 80% by mass.

4. The component for temporary fixing of electronic parts as claimed in claim 1 or 2, wherein the aforementioned release layer contains a resin with a bonding or adhesive component, and the aforementioned filler contains 10 to 300 parts by mass relative to 100 parts by mass (solids) of the aforementioned resin.

5. For the temporary fixing component of electronic parts as requested in item 1 or 2, wherein the particle size (D50) of the aforementioned filler, which has a cumulative volume percentage of 50%, is 0.1 μm or more and 20 μm or less.

6. The component for temporary fixing of electronic parts as requested in item 1 or 2, wherein the aforementioned filler contains silicon oxide.

7. For the temporary fixing component of electronic parts as requested in item 1 or 2, wherein the 5% weight reduction temperature of the aforementioned peeling layer is above 250°C.

8. The component for temporary fixing of electronic parts as requested in item 1 or 2, wherein the aforementioned core material is composed of polyimide resin or epoxy resin.

9. The component for temporary fixing of electronic parts as claimed in claim 1 or 2, wherein the thickness of the aforementioned release layer is more than 1.2 times the particle size (D90) of the aforementioned filler with a cumulative volume percentage of 90% by volume.

10. The temporary fixing component for electronic parts as requested in item 1 or 2 is in the form of tape.