TWI846784B - Adhesive tape and method for manufacturing electronic components - Google Patents

Abstract

The object of the present invention is to provide an adhesive tape and a method for manufacturing electronic components using the adhesive tape, wherein the adhesive tape can be used for a light-proof support in the manufacture of electronic components and can inhibit peeling from the adherend and the support or paste residue even when subjected to high temperature treatment. The present invention is an adhesive tape having a non-UV curing adhesive layer and a UV curing adhesive layer laminated on the non-UV curing adhesive layer, wherein the tensile strength of the non-UV curing adhesive layer at 23°C is greater than 5.0 N/10 mm and less than 20.0 N/10 mm, and the outgassing amount of the non-UV curing adhesive layer when heated at 260°C for 15 minutes is less than 10000 ppm.

Description

Adhesive tape and method for manufacturing electronic components

The present invention relates to an adhesive tape and a method for manufacturing an electronic component using the adhesive tape.

In the manufacturing process of semiconductor chips, adhesive tape is used to make the wafer or semiconductor chip easy to use during processing and to prevent damage. For example, when a thick film wafer cut from high-purity single crystal silicon is polished to a specific thickness to produce a thin film wafer, the adhesive tape is attached to the thick film wafer and then polished.

The adhesive composition used in such an adhesive tape is required to have high adhesion to firmly fix the adherend such as a wafer or a semiconductor chip during the processing step, and to be able to be peeled off without damaging the adherend such as a wafer or a semiconductor chip after the step is completed (hereinafter also referred to as "high adhesion and easy peeling"). As an adhesive composition for achieving high adhesion and easy peeling, Patent Document 1 discloses an adhesive tape using a light-curing adhesive that is cured by irradiating light such as ultraviolet rays to reduce the adhesive force. By using a light-curing adhesive as an adhesive, the adherend can be firmly fixed during the processing step, and can be easily peeled off by irradiating ultraviolet rays, etc. Prior art literature Patent literature

Patent document 1: Japanese Patent Application Publication No. 5-32946

Invent the problem you want to solve

In recent years, with the thinning and miniaturization of semiconductor products, substrates have also become thinner to less than 100 μm (hereinafter, thinned substrates are referred to as thin substrates). In order to prevent warping or damage during the manufacture of substrates, adhesive tapes are used. In the manufacture of such thin substrates, a base material such as a polyimide film that serves as the basis of the substrate is fixed to a support body via an unsupported adhesive tape, and then wiring and other processes are performed. However, from the perspective of cost or usability, the support body used to manufacture thin substrates is mostly an opaque material such as copper, aluminum, and glass epoxy. Such an opaque support body has the problem that the adhesive tape using a conventional light-curing adhesive cannot be cured. In response to this problem, an adhesive tape having a curing adhesive layer and a non-curing adhesive layer has been proposed. After the curable adhesive layer is attached to an adherend such as a thin substrate and cured, the non-curable adhesive layer is attached to a support, thereby curing the adhesive tape even when the support is opaque.

On the other hand, in the manufacturing process of electronic parts such as thin substrates, high temperature treatment of heating at 150°C or above is sometimes performed. When a conventional adhesive tape having a hardening adhesive layer and a non-hardening adhesive layer is used in the step accompanying such high temperature treatment, the non-hardening adhesive layer may not be able to resist the heat sufficiently and may be peeled off from the support. The temperature of the high temperature treatment is gradually increasing with the advancement of technology, so an adhesive tape that can be used even for an opaque support and has further heat resistance is sought.

The purpose of the present invention is to provide an adhesive tape and a method for manufacturing electronic components using the adhesive tape. The adhesive tape can also be used for opaque supports in the manufacture of electronic components, and can inhibit peeling from the adherend and the support or paste residue even when subjected to high temperature treatment. Technical means to solve the problem

The first aspect of the present invention is an adhesive tape having a non-UV curing adhesive layer and a UV curing adhesive layer laminated on the non-UV curing adhesive layer, wherein the tensile strength of the non-UV curing adhesive layer at 23°C is greater than 5.0 N/10 mm and less than 20.0 N/10 mm, and the amount of outgassing of the non-UV curing adhesive layer when heated at 260°C for 15 minutes is less than 10,000 ppm. The second aspect of the present invention is an adhesive tape having a non-ultraviolet curing adhesive layer and a UV curing adhesive layer laminated on the non-ultraviolet curing adhesive layer, wherein the amount of outgassing of the non-ultraviolet curing adhesive layer when heated at 260°C for 15 minutes is less than 10,000 ppm, and the non-ultraviolet curing adhesive layer contains (A') a (meth) acrylic copolymer as a base polymer, (B) an epoxy compound containing a tertiary amine structure as a curing agent, and (C) a filler, and the (meth) acrylic copolymer contains 92 to 97% by weight of an alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms as a constituent component. The present invention is described in detail below.

The adhesive tape of the present invention has a non-ultraviolet curing adhesive layer and an ultraviolet curing adhesive layer laminated on the non-ultraviolet curing adhesive layer. Since the adhesive tape has an ultraviolet curing adhesive layer, it can be attached to the adherend with sufficient adhesive force to protect the adherend, and the ultraviolet curing adhesive layer is cured after attachment, thereby reliably protecting the adherend even when high-temperature treatment is performed. In addition, when protection is no longer needed, the adhesive tape can be easily peeled off without damaging the adherend. Furthermore, since the adhesive tape has a non-ultraviolet curing adhesive layer, the non-ultraviolet curing adhesive layer can be attached to the support after the ultraviolet curing adhesive layer is attached to the adherend and cured, so that the ultraviolet curing adhesive layer can be cured even when the support is opaque. Furthermore, from the viewpoint of simplifying the manufacturing steps, the ultraviolet curing adhesive layer can be cured by irradiating ultraviolet rays immediately after the adhesive tape is attached to the adherend.

In a preferred embodiment of the present invention, the non-ultraviolet curing adhesive layer is ultraviolet-transmissive. Here, the so-called ultraviolet-transmissive means that the absorption band of the ultraviolet polymerization initiator contained in the ultraviolet curing adhesive layer overlaps with the light transmission band of the non-ultraviolet curing adhesive layer, and preferably, the absorption band of the ultraviolet polymerization initiator overlaps with the band of the non-ultraviolet curing adhesive layer with an absorbance of 0.2 or less. Since the non-ultraviolet curing adhesive layer is ultraviolet-transmissive, the ultraviolet curing adhesive layer can be irradiated with ultraviolet light through the non-ultraviolet curing adhesive layer.

In the first embodiment of the present invention, the tensile strength of the non-UV curing adhesive layer at 23°C is 5.0 N/10 mm or more and 20.0 N/10 mm or less. In the second embodiment of the present invention, the tensile strength of the non-UV curing adhesive layer at 23°C is preferably 5.0 N/10 mm or more and 20.0 N/10 mm or less. Since the tensile strength of the non-UV curing adhesive layer is within the above range, the adhesive tape is not easily broken during peeling. From the viewpoint of further suppressing the adhesive tape from being pulled apart during peeling, the preferred lower limit of the tensile strength of the non-UV curing adhesive layer is 5.5 N/10 mm, and the more preferred lower limit is 6.0 N/10 mm. The preferred upper limit is 19.5 N/10 mm, and the more preferred upper limit is 19.0 N/10 mm. In addition, regarding the tensile strength of the non-UV curing adhesive layer, the non-UV curing adhesive layer can be cut into a sample with a thickness of 200 μm and a width of 10 mm, and the tensile strength can be measured at 23°C and 50% RH using TENSILON UCE500 (manufactured by Orientec) at a speed of 300 mm/min and a distance between markings of 40 mm.

The amount of outgassing of the non-UV curing adhesive layer when the non-UV curing adhesive layer is heated at 260°C for 15 minutes is less than 10,000 ppm. In the manufacture of electronic parts accompanied by high temperature treatment, when a conventional adhesive tape having a non-UV curing adhesive layer and a UV curing adhesive layer is used to protect the electronic parts, the heat of the high temperature treatment will decompose the non-UV curing adhesive layer and generate a large amount of outgassing. The outgassing generated causes the non-UV curing adhesive layer to foam and reduce its strength and adhesion, thus causing the support and the non-UV curing adhesive layer to peel off during peeling, leaving adhesive tape (paste residue) on the adherend side. In the adhesive tape of the present invention, the amount of outgassing generated by the non-UV curing adhesive layer is relatively small, that is, the non-UV curing adhesive layer is not easily decomposed by heat, thereby suppressing the foaming of the non-UV curing adhesive layer, making it difficult for the adhesive tape to remain on the adherend. From the viewpoint of further suppressing the residual paste of the adhesive tape on the adherend, the above-mentioned outgassing amount is preferably 7500 ppm or less, more preferably 5500 ppm or less, further preferably 4000 ppm or less, and particularly preferably 3500 ppm or less. There is no particular limitation on the lower limit of the above-mentioned outgassing amount, and the lower the better. For example, the preferred lower limit is 1000 ppm.

The above-mentioned outgassing amount can be obtained, for example, as the gas volume (toluene conversion ppm: μg/g) when the above-mentioned non-UV curing adhesive layer is cut into 5 mm×5 mm and measured using thermal desorption GC-MS (thermal desorption device: TurboMatrix 350, manufactured by PerkinElmer; GC-MS device: JMS Q1000, manufactured by NEC Corporation). In addition, the detailed measurement conditions are as follows. Sample heating conditions: 260℃, 15 min (20 mL/min) Secondary desorption: 350℃, 40 min Flow split: inlet 25 mL/min, outlet 25 mL/min Injection volume: 2.5% Column: EQUITY-1 (non-polar, manufactured by SIGMA-ALDRICH) 0.32 mm×60 m×0.25 μm GC temperature rise: 40℃ (4 min) → temperature rise at a rate of 10℃/min → 300℃ (10 min) He flow rate: 1.5 mL/min Ionization voltage: 70 eV MS measurement range: 29～600 amu (scan 500 ms) MS temperature: ion source temperature 230℃, interface temperature 250℃

The adhesive strength of the non-UV curing adhesive layer is preferably 10 to 300 gf/3 mmφ. When the adhesive strength of the non-UV curing adhesive layer is within the above range, the non-UV curing adhesive layer and the support are more securely bonded, and the adhesive tape can be more easily peeled off from the interface between the UV curing adhesive layer and the adherend during peeling. From the viewpoint of making it easier to peel the adhesive tape from the interface between the UV-curing adhesive layer and the adherend, the lower limit of the above-mentioned adhesive strength is preferably 15 gf/3 mmϕ, and further preferably 20 gf/3 mmϕ, and the upper limit is preferably 270 gf/3 mmϕ, and further preferably 250 gf/3 mmϕ. Furthermore, the above-mentioned adhesive strength can be measured by cutting the non-UV-curing adhesive layer into 10 mm×10 mm to prepare a measurement sample, and performing a probe viscosity measurement on the obtained measurement sample. Furthermore, the measurement tool or measurement conditions used can be set as follows. Adhesion tester: TAC1000, manufactured by RHESCA (or equivalent) Probe diameter: 3 mmφ Compression load: 100 g Compression time: 1 second Contact speed: 30 mm·min Peeling speed: 600 mm/min

The gel fraction of the non-UV curing adhesive layer is preferably 80% or more. By having a gel fraction of 80% or more, the chemical resistance of the non-UV curing adhesive layer is improved, so the adhesive tape of the present invention can also be used in the step of accompanying chemical treatment. From the perspective of further improving chemical resistance, the gel fraction is more preferably 95% or more, and further preferably 97% or more. The upper limit of the gel fraction is not particularly limited, and is usually 100% or less. Furthermore, the gel fraction can be measured by the following method. Only 0.1 g of the non-UV curing adhesive layer of the obtained adhesive tape was scraped off and immersed in 50 mL of ethyl acetate. The non-UV curing adhesive layer was vibrated for 24 hours at 23 degrees and 120 rpm using a vibrator (hereinafter, the scraped non-UV curing adhesive layer is referred to as the adhesive composition). After vibration, a metal wire mesh (mesh size #200) was used to separate the ethyl acetate from the adhesive composition that swelled after absorbing the ethyl acetate. The separated adhesive composition was dried at 110°C for 1 hour. The weight of the adhesive composition including the metal wire mesh after drying was measured, and the gel fraction of the non-UV curing adhesive layer was calculated using the following formula. Gel fraction (weight %) = 100 × (W ₁ - _{W 2} ) / W ₀ (W ₀ : initial weight of adhesive composition, W ₁ : weight of adhesive composition including metal mesh after drying, W ₂ : initial weight of metal mesh)

The non-UV curing adhesive constituting the above-mentioned non-UV curing adhesive layer is not particularly limited as long as it is non-UV curing and satisfies the above-mentioned tensile strength and outgassing amount. It is preferred that the base polymer has a functional group capable of reacting with an epoxy group. As the above-mentioned functional group capable of reacting with an epoxy group, for example, there can be listed: carboxyl, hydroxyl, phenolic, ester, amino, carbonyl, methoxy and sulfonic groups. Among them, in terms of higher reactivity, it is preferred to select at least one of the group consisting of carboxyl, hydroxyl, phenolic, ester and amino groups.

As the above-mentioned base polymer, for example, acrylic polymers, silicone polymers, amine polymers, etc. can be listed. In the first aspect of the present invention, the above-mentioned non-UV curing adhesive layer preferably contains (A) as a base polymer (meth) acrylic copolymer, which contains (a) 92 to 97% by weight of (meth) acrylic acid alkyl esters having 4 to 12 carbon atoms in the alkyl group and (b) 3.0 to 8.0% by weight of carboxyl-containing monomers as constituents, and (c) a weight average molecular weight of 700,000 or more (d) a molecular weight distribution of 2 to 6. In the second aspect of the present invention, the above-mentioned non-UV curing adhesive layer contains (A') as a base polymer (meth) acrylic copolymer, which contains 92 to 97% by weight of (meth) acrylic acid alkyl esters having 4 to 12 carbon atoms in the alkyl group as constituents. In the second aspect of the present invention, it is also preferred that the (meth)acrylic acid copolymer comprises 92 to 97% by weight of an alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms, 3.0 to 8.0% by weight of a carboxyl group-containing monomer, and has a weight average molecular weight of more than 700,000 and a molecular weight distribution of 2 to 6.

By using the above-mentioned (meth) acrylate alkyl ester having an alkyl group with 4 to 12 carbon atoms as a constituent, a non-UV curing adhesive layer with better adhesion (preferably with UV transmittance) can be prepared. In addition, by using a carboxyl group-containing monomer as a constituent, the cohesive force of the non-UV curing adhesive can be increased, giving greater adhesion. Furthermore, when the above-mentioned UV curing adhesive layer contains a polysilicone compound, since the carboxyl group as a polar group blocks the approach of the low-polarity polysilicone compound, the polysilicone compound can be inhibited from permeating to the non-UV curing adhesive layer.

Examples of the (meth)acrylic acid alkyl esters having an alkyl group with 4 to 12 carbon atoms include butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, etc. Among them, butyl acrylate is preferred in terms of excellent adhesion.

Examples of the carboxyl group-containing monomer include acrylic acid and methacrylic acid. Of these, acrylic acid is preferred in terms of imparting high adhesion.

By having an alkyl (meth)acrylate content of 4 to 12 carbon atoms in the alkyl group of 92 to 97% by weight, an adhesive tape with better adhesion can be produced. By having a carboxyl-containing monomer content of 3.0% by weight or more, when the UV-curing adhesive layer contains a polysilicone compound, the permeation of the polysilicone compound into the non-UV-curing adhesive layer can be further suppressed. By having a carboxyl-containing monomer content of 8.0% by weight or less, the acidity of the (meth)acrylic copolymer can be adjusted to a suitable range, and when the UV-curing adhesive layer contains a polysilicone compound, the permeation of the polysilicone compound into the non-UV-curing adhesive layer can be further suppressed. From the viewpoint of further suppressing the exudation, the lower limit of the content of the alkyl (meth)acrylate in the (meth)acrylic copolymer is preferably 93% by weight, further preferably 94% by weight, and further preferably 96% by weight. From the viewpoint of further suppressing the exudation, the lower limit of the content of the carboxyl group-containing monomer in the (meth)acrylic copolymer is preferably 4.0% by weight, and further preferably 7.0% by weight, and further preferably 6.0% by weight.

Since the (meth) acrylic copolymer has a relatively large weight average molecular weight of more than 700,000 and a relatively narrow molecular weight distribution of 2 to 6, the tensile strength of the non-UV curing adhesive layer and the above-mentioned outgassing amount can be easily adjusted to the above-mentioned range. Furthermore, here, the so-called molecular weight distribution refers to the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn). The preferred lower limit of the above-mentioned weight average molecular weight is 750,000, and the further preferred lower limit is 800,000. The upper limit of the above-mentioned weight average molecular weight is not particularly limited, and from the perspective of usability, for example, the preferred upper limit is 1.2 million. In addition, the preferred lower limit of the above-mentioned molecular weight distribution is 2.5, and the further preferred lower limit is 3, and the further preferred upper limit is 5.5, and the further preferred upper limit is 5. The weight average molecular weight and molecular weight distribution can be determined by GPC measurement, and specifically, the method shown in the embodiment can be used. Methods for obtaining the (meth)acrylic acid copolymer having the weight average molecular weight and molecular weight distribution include, for example, solution polymerization, emulsion polymerization, and living free radical polymerization.

In the first aspect of the present invention, the non-UV curing adhesive layer preferably contains (B) an epoxy compound as a curing agent, and more preferably contains an epoxy compound containing a tertiary amine structure. In the second aspect of the present invention, the non-UV curing adhesive layer contains (B) an epoxy compound containing a tertiary amine structure as a curing agent. By containing an epoxy compound in the non-UV curing adhesive layer, the base polymer can be crosslinked, thereby improving the chemical resistance and heat resistance of the non-UV curing adhesive layer. In addition, the gel fraction of the crosslinked base polymer is increased, and a molecular structure that is not easy to move is formed. Therefore, when the UV-curable adhesive layer contains a polysilicone compound, the polysilicone compound can be prevented from permeating into the non-UV-curable adhesive layer, and sufficient adhesion can be exerted even after long-term storage. Examples of the epoxy compound include: N,N,N',N'-tetraglycidyl-1,3-phenylenedi(methylamine), methyl glycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, bis-(3,4-epoxycyclohexyl) adipate, bisphenol A diglycidyl ether, bisphenol A diglycidyl ether condensate, epichlorohydrin modified products of novolac resin or cresol resin, and the like. Among them, epoxy compounds containing a tertiary amine structure are preferred.

The base polymer before the crosslinking reaction with the epoxy compound has a low gel fraction and a structure in which the molecules can easily move. Therefore, when the above-mentioned UV-curing adhesive layer contains polysilicone, the polysilicone easily permeates. Therefore, if the crosslinking reaction rate is slow, the polysilicone will permeate into the non-UV-curing adhesive layer in large quantities. If the non-UV-curing adhesive layer contains tertiary amine groups, the tertiary amine groups act as catalysts for the crosslinking reaction, and the crosslinking reaction rate of the base polymer is accelerated, so the reaction is completed at an early stage. By completing the crosslinking reaction at an early stage, the polysilicone compound is not easy to penetrate into the non-UV curing adhesive layer, so that an adhesive tape having sufficient adhesion even after long-term storage can be produced. Examples of the above-mentioned epoxy compound having a tertiary amine include N,N,N',N'-tetraglycidyl-1,3-phenylenedi(methylamine) and the like.

The content of the curing agent (the epoxy compound) in the non-UV curing adhesive layer is preferably 0.1 parts by weight, more preferably 0.2 parts by weight, and further preferably 0.3 parts by weight, and the upper limit is preferably 0.5 parts by weight, more preferably 0.45 parts by weight, and further preferably 0.4 parts by weight, relative to 100 parts by weight of the base polymer. When the content of the epoxy compound is within the above range, the base polymer can be fully and quickly crosslinked, and the permeation of the polysilicone compound into the non-UV curing adhesive layer can be further suppressed.

In the first aspect of the present invention, the non-UV curing adhesive layer preferably contains (C) filler. In the second aspect of the present invention, the non-UV curing adhesive layer contains (C) filler. The heat resistance can be improved by the non-UV curing adhesive layer containing filler. Examples of the filler include: silica filler, aluminum filler, calcium filler, boron filler, magnesium filler, zirconia filler, etc. Among them, silica filler is preferred.

In the case where the UV-curable adhesive layer contains a polysilicone compound, the silica filler is preferably a silica filler oxide, which can further suppress the permeation of the polysilicone compound. Since the silica filler oxide has a hydrophilic group and is highly polar, the non-UV-curable adhesive layer can be blocked from approaching substances with lower polarity by containing the silica filler oxide. Therefore, when the UV-curable adhesive layer contains a polysilicone compound with low polarity, the permeation of the polysilicone compound into the non-UV-curable adhesive layer can be suppressed.

The silica filler oxide is not particularly limited, and examples thereof include silicon-aluminum-boron composite oxide, silicon-titanium composite oxide, silicon dioxide-titania composite oxide, magnesium-aluminum-silicon composite oxide, hexamethylcyclotrisiloxane, tetramethoxysilane, chlorosilane, monosilane, etc. Among them, silicon-aluminum-boron composite oxide, silicon-titanium composite oxide, and silicon dioxide-titania composite oxide are preferred in terms of having physical properties similar to those of silica commonly used as an inorganic filler.

When the silica filler is a silica filler oxide, the silica filler oxide is preferably treated with hydrophobic treatment on at least a portion of the surface. By replacing at least a portion of the hydrophilic groups present in the silica filler oxide with hydrophobic groups, the dispersibility in the base polymer can be improved. The hydrophobic group is not particularly limited, and examples thereof include methyl, ethyl, propyl, butyl, etc. Among them, from the viewpoint of dispersibility in the base polymer, the silica filler oxide after the hydrophobic treatment preferably has a monomethylsilyl group, a dimethylsilyl group, or a trimethylsilyl group. In particular, in terms of the excellent balance between the effect of suppressing the permeation of the polysilicone compound into the non-UV curing adhesive layer and the dispersibility in the base polymer, it is more preferable that at least a portion of the above-mentioned silica filler oxide has a monomethylsilyl group. Furthermore, as mentioned above, the silica filler oxide blocks the approach of the polysilicone compound by its hydrophilicity, so the silica filler oxide whose surface is completely substituted with hydrophobic groups is difficult to exert the effect of a silica filler oxide.

When at least a portion of the silica filler oxide has a monomethylsilyl group, a dimethylsilyl group or a trimethylsilyl group, the silica filler oxide preferably has the functional group of 100 m ² /g or more, more preferably 140 m ² /g or more, based on the bulk specific surface area. When the silica filler oxide has the functional group within the above range on the surface, the dispersibility of the silica filler oxide in the base polymer can be further improved.

The average particle size of the filler is not particularly limited, but the preferred lower limit is 0.06 μm, and the more preferred lower limit is 0.07 μm, and the preferred upper limit is 2 μm, and the more preferred upper limit is 1 μm. When the average particle size of the filler is within the above range, the dispersibility in the non-UV curing adhesive can be further improved.

The content of the above-mentioned filler is not particularly limited. The preferred lower limit is 3 parts by weight relative to 100 parts by weight of the above-mentioned base polymer, and the preferred upper limit is 20 parts by weight. By having a filler content of more than 3 parts by weight, the heat resistance of the obtained adhesive tape can be further improved. By having a silica filler content of less than 20 parts by weight, an adhesive tape with sufficient adhesion can be prepared. From the viewpoint of further improving the heat resistance of the adhesive tape, the preferred lower limit of the content of the above-mentioned silica filler relative to 100 parts by weight of the above-mentioned base polymer is 6 parts by weight, and further the preferred lower limit is 8 parts by weight, and the preferred upper limit is 18 parts by weight, and further the preferred upper limit is 15 parts by weight, and the particularly preferred upper limit is 13 parts by weight.

The above-mentioned non-UV curing adhesive layer may also contain an adhesive agent. By containing an adhesive agent in the above-mentioned non-UV curing adhesive layer, the adhesion can be further improved. However, the adhesive agent will also cause outgassing when treated at high temperature, so it is better not to use it or reduce the amount used as much as possible. Therefore, when using an adhesive agent, the above-mentioned non-UV curing adhesive layer preferably contains 30 parts by weight or less of the adhesive agent relative to 100 parts by weight of the above-mentioned (meth) acrylic copolymer. By setting the content of the adhesive agent to the above range, the generation of outgassing caused by heat can be suppressed, and it is easy to adjust to the above-mentioned outgassing amount. The upper limit of the above-mentioned adhesion-imparting agent is more preferably 20 parts by weight, and further preferably 10 parts by weight. The lower limit of the above-mentioned adhesion-imparting agent is not particularly limited, but is preferably 0 parts by weight from the viewpoint of minimizing the amount of outgassing, and is preferably 3 parts by weight from the viewpoint of further improving the adhesion.

The non-UV curing adhesive layer may also contain known additives such as plasticizers, resins, surfactants, waxes, and microparticle fillers. One or more of the additives may be used.

The thickness of the non-UV curing adhesive layer is not particularly limited, and the preferred lower limit is 5 μm, the more preferred lower limit is 10 μm, and the preferred upper limit is 100 μm, the more preferred upper limit is 60 μm. If the thickness of the non-UV curing adhesive layer is within the above range, it can be bonded to the support with sufficient adhesion to securely fix the adherend.

As the UV-curable adhesive component constituting the UV-curable adhesive layer, for example, there can be cited a UV-curable adhesive having a polymerizable polymer as a main component and containing a UV polymerization initiator as a polymerization initiator. The polymerizable polymer can be obtained by, for example, pre-synthesizing a (meth)acrylic polymer having a functional group in the molecule (hereinafter referred to as a (meth)acrylic polymer containing a functional group) and reacting it with a compound having a functional group that reacts with the functional group and a free radical polymerizable unsaturated bond in the molecule (hereinafter referred to as an unsaturated compound containing a functional group).

The above-mentioned (meth) acrylic polymer containing a functional group is obtained by copolymerizing an alkyl acrylate and/or alkyl methacrylate whose alkyl group has a carbon number of 2 to 18 as a main monomer with a monomer containing a functional group and, if necessary, other monomers for modification that can copolymerize with the above-mentioned monomers by a conventional method. The weight average molecular weight of the above-mentioned (meth) acrylic polymer containing a functional group is generally about 200,000 to 2,000,000. In addition, in this specification, the weight average molecular weight can generally be determined by the GPC method, and specifically, the method shown in the examples can be adopted.

Examples of the above-mentioned monomers containing functional groups include carboxyl group-containing monomers, hydroxyl group-containing monomers, epoxy group-containing monomers, isocyanate group-containing monomers, and amino group-containing monomers. Examples of the above-mentioned monomers containing carboxyl group include acrylic acid and methacrylic acid. Examples of the above-mentioned monomers containing hydroxyl group include hydroxyethyl acrylate and hydroxyethyl methacrylate. Examples of the above-mentioned monomers containing epoxy group include glycidyl acrylate and glycidyl methacrylate. Examples of the above-mentioned monomers containing isocyanate group include isocyanate ethyl acrylate and isocyanate ethyl methacrylate. Examples of the above-mentioned monomers containing amino group include aminoethyl acrylate and aminoethyl methacrylate.

Examples of the other copolymerizable modifying monomers include various monomers commonly used in (meth)acrylic acid polymers, such as vinyl acetate, acrylonitrile, and styrene.

As the functional group-containing unsaturated compound that reacts with the functional group-containing (meth)acrylic polymer, the same as the functional group-containing monomer can be used according to the functional group of the functional group-containing (meth)acrylic polymer. For example, when the functional group of the functional group-containing (meth)acrylic polymer is a carboxyl group, an epoxy group-containing monomer or an isocyanate group-containing monomer is used. When the functional group of the functional group-containing (meth)acrylic polymer is a hydroxyl group, an isocyanate group-containing monomer is used. When the functional group of the functional group-containing (meth)acrylic polymer is an epoxy group, a carboxyl group-containing monomer or an amide group-containing monomer such as acrylamide is used. When the functional group of the functional group-containing (meth)acrylic polymer is an amino group, an epoxy group-containing monomer is used.

The above-mentioned ultraviolet polymerization initiator can be, for example, activated by irradiation with ultraviolet light of a wavelength of 200 to 410 nm. As such ultraviolet polymerization initiators, for example, acetophenone derivative compounds, benzoin ether compounds, ketal derivative compounds, phosphine oxide derivative compounds, bis(η5-cyclopentadienyl)titaniumocene derivative compounds, benzophenone, michler's ketone, chloro-9-oxysulfur , dodecyl 9-oxysulfide , dimethyl 9-oxysulfide , diethyl 9-sulfoxide , α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethylphenyl propane, etc. Examples of the above-mentioned acetophenone derivative compounds include methoxyacetophenone, etc. Examples of the above-mentioned benzoin ether compounds include benzoin propyl ether, benzoin isobutyl ether, etc. Examples of the above-mentioned ketal derivative compounds include benzoyl dimethyl ketal, acetophenone diethyl ketal, etc. These ultraviolet polymerization initiators may be used alone or in combination of two or more.

The above-mentioned UV-curable adhesive layer preferably contains a free radical polymerizable multifunctional oligomer or monomer. The UV curability is improved by the above-mentioned UV-curable adhesive layer containing a free radical polymerizable multifunctional oligomer or monomer. The above-mentioned multifunctional oligomer or monomer preferably has a weight average molecular weight of 10,000 or less, and more preferably has a weight average molecular weight of 5,000 or less and the number of free radical polymerizable unsaturated bonds in the molecule is 2 to 20, so that the UV-curable adhesive layer can be efficiently three-dimensionally networked by irradiating ultraviolet rays. The above-mentioned weight average molecular weight can be determined, for example, by GPC measurement, and specifically, the method shown in the embodiment can be adopted.

Examples of the multifunctional oligomers or monomers include trihydroxymethylpropane triacrylate, tetrahydroxymethylmethane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxy pentaacrylate, dipentaerythritol hexaacrylate, or the same methacrylates as above. In addition, examples include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylates, and the same methacrylates as above. These multifunctional oligomers or monomers may be used alone or in combination of two or more.

The UV-curable adhesive layer preferably contains polysilicone. Since the UV-curable adhesive layer contains polysilicone, the adhesive tape can be easily peeled off after the treatment because the polysilicone seeps out at the interface between the UV-curable adhesive layer and the adherend. In addition, since polysilicone has excellent heat resistance, even when the treatment is accompanied by heating at 150°C or above, the UV-curable adhesive layer can be prevented from being scorched, thereby preventing the adhesive from remaining.

The polysilicone compound preferably has a functional group capable of crosslinking with the UV-curing adhesive component. Since the polysilicone compound has a functional group capable of crosslinking with the UV-curing adhesive component, the polysilicone compound reacts with the UV-curing adhesive component and is incorporated into the UV-curing adhesive component after irradiation with ultraviolet light, thereby suppressing the contamination caused by the polysilicone compound adhering to the adherend. The functional valence of the polysilicone compound is, for example, 2 to 6, preferably 2 to 4, and more preferably 2. The functional group is appropriately determined according to the functional group contained in the UV-curing adhesive component. For example, when the UV-curing adhesive component is a light-curing adhesive with a (meth) alkyl ester polymer as the main component, a functional group capable of crosslinking with a (meth) acrylic acid group is selected. The functional group capable of crosslinking with a (meth) acrylic acid group is a functional group having an unsaturated double bond. Specifically, for example, a polysiloxane containing a vinyl group, a (meth) acrylic acid group, an allyl group, a maleimide group, etc. is selected.

The weight average molecular weight of the polysilicone compound is preferably 300 to 50,000. When the weight average molecular weight of the polysilicone compound is 300 or more, its larger molecular size can be used to further suppress the permeation into the non-UV curing adhesive layer. When the weight average molecular weight is 50,000 or less, the permeation into the interface between the UV curing adhesive layer and the adherend and the subsequent hyperplasia can be further suppressed. The weight average molecular weight of the polysilicone compound is preferably 400, and further preferably 500, and the upper limit is preferably 10,000, and further preferably 5,000. Furthermore, in the present invention, the weight average molecular weight of the polysilicone compound can be determined by GPC analysis, and specifically, the method shown in the embodiment can be adopted.

As the polysilicone compound having the above functional group and weight average molecular weight, for example, silicon diacrylate can be cited. When silicon diacrylate is used, heat resistance and peeling property are further improved.

The preferred content of the polysilicone compound is 1 part by weight and 50 parts by weight relative to 100 parts by weight of the polymerizable polymer, with a more preferred lower limit of 10 parts by weight and a more preferred upper limit of 40 parts by weight. When the content of the polysilicone compound is within the above range, the adherend can be protected with sufficient adhesion, and the adhesive tape can be more easily peeled off after the protection is completed.

The UV-curable adhesive layer may also contain known additives such as inorganic fillers such as fuming silica, plasticizers, resins, surfactants, waxes, and microparticle fillers.

The thickness of the UV-curable adhesive layer is not particularly limited, but preferably has a lower limit of 5 μm and an upper limit of 100 μm. If the thickness of the UV-curable adhesive layer is within the above range, the adherend can be protected with sufficient adhesion, and the residual paste during peeling can be suppressed. From the perspective of further improving the adhesion and further suppressing the residual paste during peeling, the thickness of the UV-curable adhesive layer has a better lower limit of 10 μm and a better upper limit of 60 μm.

The adhesive tape of the present invention is preferably a double-sided adhesive tape without a substrate. In the case of a supported type with a substrate, there is no polysilicone compound seeping out to the interface of the support body side, but a heat-resistant substrate must be used, so the cost is higher than that of the unsupported type.

The adhesive tape of the present invention preferably has a release film (preferably UV-transmissive) on the surface of the non-UV-curing adhesive layer opposite to the surface on which the UV-curing adhesive layer is layered. By providing a release film on the non-UV-curing adhesive layer, the non-UV-curing adhesive layer can be protected before being attached to the adherend, and the usability of the adhesive tape can be improved. In addition, when the release film is UV-transmissive, the following curing step can be performed while the non-UV-curing adhesive layer is protected.

The mold release film is not particularly limited, and examples thereof include: polyethylene naphthalate (PEN), polyimide (PI), polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyhexamethylene terephthalate, polybutylene naphthalate, butylene terephthalate polytetramethylene glycol copolymer, butylene terephthalate polycaprolactone copolymer and other ultraviolet light-transmitting films. Among them, polyethylene terephthalate (PET) is preferred.

As long as the UV-curing adhesive layer and the non-UV-curing adhesive layer are located at the outermost layer (the layer in contact with the adherend), the adhesive tape of the present invention may further have other layers between the UV-curing adhesive layer and the non-UV-curing adhesive layer.

The tensile strength of the adhesive tape of the present invention at 23°C before curing is preferably 2.5 to 10 N/10 mm. By having the tensile strength of the adhesive tape before curing be within the above range, the adhesive tape is not easily pulled apart during peeling. From the viewpoint of further suppressing the adhesive tape from being pulled apart during peeling, the better lower limit of the tensile strength of the adhesive tape before curing is 3.0 N/10 mm, and further the better lower limit is 3.5 N/10 mm, and the better upper limit is 9.5 N/10 mm, and further the better upper limit is 9.0 N/10 mm. Furthermore, the tensile strength of the adhesive tape before curing can be measured by the same method as the tensile strength of the non-UV curing adhesive layer.

The adhesive tape of the present invention preferably has a gel fraction of 80% or more in the UV-curing adhesive layer after UV curing. By having a gel fraction of the UV-curing adhesive layer of more than the above lower limit, the chemical resistance of the adhesive tape can be further improved, and the polysilicone compound can be further inhibited from seeping into the non-UV-curing adhesive layer over time. The better lower limit of the gel fraction of the UV-curing adhesive layer is 85%, and the further better lower limit is 90%. The upper limit of the gel fraction of the UV-curing adhesive layer is not particularly limited, and is preferably 99%. Furthermore, when the adhesive tape has a layer other than the UV-curing adhesive layer and the non-UV-curing adhesive layer, it is preferred that the layer also satisfies the above-mentioned gel fraction.

The method for manufacturing the adhesive tape of the present invention is not particularly limited, and a previously known method can be used. For example, the adhesive tape can be manufactured by the following method: a solution of the above-mentioned UV-curable adhesive component is applied on a film that has been subjected to a demolding treatment, and the solution is dried to form a UV-curable adhesive layer, and a non-UV-curable adhesive layer is formed on another film that has been subjected to a demolding treatment by the same method, and then the UV-curable adhesive layer and the non-UV-curable adhesive layer are laminated.

The use of the adhesive tape of the present invention is not particularly limited, and it can be particularly preferably used as a protective tape when manufacturing electronic components such as electronic substrates or semiconductor chips using an opaque support and a manufacturing step accompanied by high temperature treatment. As a manufacturing method for such electronic components, for example, the following manufacturing methods for electronic components can be listed. That is, the method includes the following steps: an adherend attaching step, which is to attach the adherend from the above-mentioned UV-curing adhesive layer; a curing step, which is to irradiate UV rays to cure the above-mentioned UV-curing adhesive layer; a support attaching step, which is to attach the support to the above-mentioned non-UV-curing adhesive layer; a heat treatment step, which is to treat the above-mentioned adherend at a high temperature of more than 150°C; and a peeling step, which is to peel the above-mentioned adherend from the above-mentioned adhesive tape. This method for manufacturing electronic components can particularly advantageously show the effect of the present invention.

Furthermore, one of the present inventions is also a method for manufacturing electronic components, which includes the following steps: an adherend attaching step, which is to attach the adhesive tape of the present invention to the adherend from the UV-curing adhesive layer; a curing step, which is to irradiate UV rays to harden the above-mentioned UV-curing adhesive layer; a support attaching step, which is to attach a support to the above-mentioned non-UV-curing adhesive layer; a heat treatment step, which is to treat the above-mentioned adherend at a high temperature of more than 150°C; and a peeling step, which is to peel the above-mentioned adherend from the above-mentioned adhesive tape.

In the manufacturing method of the electronic component of the present invention, the attaching step is first performed: the adhesive tape of the present invention having a UV-curing adhesive layer and a non-UV-curing adhesive layer is attached to the adherend from the UV-curing adhesive layer. As the above-mentioned adherend, there can be listed: silicon wafers, semiconductor chips, base substrates when manufacturing electronic substrates, materials for electronic components, etc. As the above-mentioned substrates, there can be listed: polyimide films, glass epoxy substrates, etc.

In the manufacturing method of the electronic component of the present invention, a curing step is then performed: irradiating ultraviolet rays to cure the above-mentioned ultraviolet curing adhesive layer. By curing the ultraviolet curing adhesive layer, the paste residue can be suppressed, and the adhesive tape can be easily peeled off from the adherend after the treatment. In the manufacturing method of the electronic component of the present invention, since the ultraviolet curing adhesive layer is cured before the adhesive tape is attached to the support, the ultraviolet curing adhesive layer can be cured even if the support is a light-opaque material. Furthermore, when the non-UV curing adhesive layer of the adhesive tape is UV-transmissive, the UV curing adhesive layer can be fully cured even when UV rays are irradiated from the non-UV curing adhesive layer to the UV curing adhesive layer. Furthermore, since the UV curing adhesive layer is cured after being attached to the adherend, the adhesive tape will not immediately peel off the adherend even when the UV curing adhesive layer is cured before the adherend is treated.

The light irradiation conditions for curing the above-mentioned UV-curable adhesive layer can be appropriately adjusted according to the combination of the above-mentioned polymerizable polymer and the above-mentioned UV polymerization initiator used. For example, when using a polymerizable polymer having unsaturated double bonds such as vinyl groups in the side chain and a UV polymerization initiator activated by light of a wavelength of 200 to 410 nm, the above-mentioned UV-curable adhesive layer can be crosslinked and cured by irradiating light of a wavelength of 365 nm or more. For such a UV-curable adhesive layer, for example, it is preferred to irradiate with light of a wavelength of 365 nm at an illumination of 5 mW or more, more preferably at an illumination of 10 mW or more, further preferably at an illumination of 20 mW or more, and even more preferably at an illumination of 50 mW or more. Furthermore, it is preferred to irradiate with light of a wavelength of 365 nm at a cumulative illuminance of 300 mJ or more, more preferably at a cumulative illuminance of 500 mJ or more and 10000 mJ or less, further preferably at a cumulative illuminance of 500 mJ or more and 7500 mJ or less, and particularly preferably at a cumulative illuminance of 1000 mJ or more and 5000 mJ or less.

In the manufacturing method of the electronic component of the present invention, the support body attaching step is then performed: attaching the support body on the non-ultraviolet curing adhesive layer. In the manufacturing method of the electronic component of the present invention, since the adhesive layer of the adhesive tape is divided into an ultraviolet curing adhesive layer and a non-ultraviolet curing adhesive layer, even when the curing step is performed before the support body is attached, the non-ultraviolet curing adhesive layer will not be cured. Therefore, the adhesive tape can be attached to the support body with sufficient adhesive force. Furthermore, in the case where the adhesive tape has the above-mentioned ultraviolet-transmissive release film, the above-mentioned release film is peeled off after the above-mentioned curing step is completed and before the above-mentioned support body attaching step.

In the manufacturing method of the electronic component of the present invention, a heat treatment step is then performed: the adherend is treated at a high temperature of 150°C or above. As the above-mentioned heat treatment step, a substrate manufacturing step or a chip mounting step can be listed. In the above-mentioned substrate manufacturing step, a heat treatment of 150°C or above is usually performed, and in the above-mentioned chip mounting step, a heat treatment of 200°C or above is usually performed. In the manufacturing method of the electronic component of the present invention, since the ultraviolet curing adhesive layer has been cured before the heat treatment step, even if the heat treatment step is accompanied by a high temperature of 150°C or above, the hyperadhesion can be suppressed, and the adherend can be easily peeled off after the treatment is completed. Furthermore, since the UV-curable adhesive layer contains polysilicone, it is possible to further suppress hyperadhesion.

The manufacturing method of the electronic component of the present invention further has a peeling step of peeling the adherend from the adhesive tape. Since the UV-curing adhesive layer is crosslinked and cured in the curing step, the adhesive residue can be suppressed and the adherend can be easily peeled from the adhesive tape. In addition, since the gas release amount of the non-UV-curing adhesive layer of the adhesive tape is less than 10,000 ppm, the non-UV-curing adhesive layer is not easy to bubble due to gas release in the heat treatment step. As a result, the adhesive tape is not easy to peel off between the support and the non-UV-curing adhesive layer, so it can also be suppressed that the adhesive tape remains on the adherend side during peeling. Furthermore, since the tensile strength of the non-UV curing adhesive layer is within a certain range, the adhesive tape is not easily torn when peeling. Effect of the invention

According to the present invention, an adhesive tape and a method for manufacturing electronic components using the adhesive tape can be provided. The adhesive tape can also be used for an opaque support in the manufacture of electronic components, and can suppress peeling from the adherend and the support or paste residue even when a high temperature treatment is performed.

The following embodiments are used to illustrate the present invention in more detail, but the present invention is not limited to these embodiments.

(Example 1) (Manufacturing of non-UV curing adhesive) In a reactor equipped with a thermometer, a stirrer, and a cooling tube, 97 parts by weight of butyl acrylate as a (meth)acrylic acid alkyl ester, 3 parts by weight of acrylic acid as a carboxyl group-containing monomer, and 120 parts by weight of ethyl acetate were added, and after nitrogen replacement, the reactor was heated and refluxed. Then, 0.1 parts by weight of azobisisobutyronitrile as a polymerization initiator was added to the above reactor. Refluxed at 70°C for 5 hours to obtain a solution of a (meth)acrylic acid copolymer (base polymer). The weight average molecular weight and molecular weight distribution of the obtained (meth)acrylic acid copolymer were measured by GPC method in terms of polystyrene, and the results were 1 million and 3, respectively. In addition, the measuring machine and measuring conditions were set as described below. Measuring device: 2690 Separations Model, manufactured by Waters Corporation Column: GPC KF-806L, manufactured by Showa Denko Co., Ltd. Detector: Differential refractometer Sample flow rate: 1 mL/min Column temperature: 40°C Eluent: Ethyl acetate

Next, 0.35 parts by weight of epoxy curing agent and 10 parts by weight of silica filler were added to 100 parts by weight of the solid content of the (meth)acrylic copolymer solution obtained, and the mixture was stirred to obtain an ethyl acetate solution of a non-UV curing adhesive. The following epoxy curing agent and silica filler were used. Epoxy curing agent: TETRAD-X, manufactured by Mitsubishi Gas Chemical Co., Ltd., epoxy curing agent containing a tertiary amine group Silica filler: REOLOSIL MT-10, manufactured by Tokuyama Co., Ltd.

(Production of UV-curable adhesive) Prepare a reactor equipped with a thermometer, a stirrer, and a cooling tube. Add 94 parts by weight of 2-ethylhexyl acrylate as an alkyl (meth)acrylate, 6 parts by weight of hydroxyethyl methacrylate as a functional group-containing monomer, 0.01 parts by weight of lauryl mercaptan, and 80 parts by weight of ethyl acetate to the reactor, and then heat the reactor to start reflux. Then, add 0.01 parts by weight of 1,1-bis(tert-hexyl peroxide)-3,3,5-trimethylcyclohexane as a polymerization initiator to the reactor, and start polymerization under reflux. Then, 0.01 parts by weight of 1,1-bis(tert-hexyl peroxide)-3,3,5-trimethylcyclohexane was added 1 hour and 2 hours after the start of the polymerization, and 0.05 parts by weight of trimethylhexyl peroxide was added 4 hours after the start of the polymerization to continue the polymerization reaction. Furthermore, 8 hours after the start of the polymerization, an ethyl acetate solution of a functional group-containing (meth)acrylic polymer with a solid content of 55% by weight and a weight average molecular weight of 600,000 was obtained. 3.5 parts by weight of 2-isocyanatoethyl methacrylate as an unsaturated compound containing a functional group was added to 100 parts by weight of the resin solid content of the obtained ethyl acetate solution containing a functional group-containing (meth)acrylic polymer to react and obtain a polymerizable polymer. Then, 20 parts by weight of silicon diacrylate as a polysilicone compound, 3 parts by weight of silica filler, 30 parts by weight of acrylate amine, 0.7 parts by weight of isocyanate crosslinking agent, and 1 part by weight of photopolymerization initiator were mixed with 100 parts by weight of the resin solid content of the obtained ethyl acetate solution of the polymerizable polymer to obtain an ethyl acetate solution of a UV-curable adhesive. The silicon diacrylate, silica filler, acrylate amine, isocyanate crosslinking agent, and photopolymerization initiator used were as follows. Silicone diacrylate: EBECRYL 350, manufactured by DAICEL-ALLNEX, weight average molecular weight 1000 Silica filler: REOLOSIL MT-10, manufactured by Tokuyama Amine acrylate: UN-5500, manufactured by Negami Industries Isocyanate crosslinking agent: Coronate L, manufactured by Nippon Urethane Industry Photopolymerization initiator: Esacure One, manufactured by Nihon SiberHegner

(Manufacturing of adhesive tape) The obtained UV-curable adhesive solution was applied to a 50 μm thick polyethylene terephthalate (PET) film subjected to a mold release treatment on one side so that the dry film thickness was 40 μm, and the applied solution was dried by heating at 110°C for 5 minutes to obtain a UV-curable adhesive layer. The obtained non-UV-curable adhesive solution was applied to a 50 μm thick transparent PET film subjected to a mold release treatment on one side so that the dry film thickness was 40 μm, and the applied solution was dried by heating at 110°C for 5 minutes to obtain a non-UV-curable adhesive layer. The surfaces of the obtained UV-curing adhesive layer and the non-UV-curing adhesive layer on which the PET film was not laminated were bonded to each other to obtain an adhesive tape.

(Determination of tensile strength) An adhesive tape consisting only of a non-UV curing adhesive layer was prepared by the above method. The non-UV curing adhesive layer was cut into pieces with a thickness of 200 μm and a width of 10 mm as a sample, and the tensile strength was measured at a speed of 300 mm/min and a distance between markings of 40 mm at 23°C and 50% RH using TENSILON UCE500 (manufactured by Orientec). The tensile strength of the obtained adhesive tape before curing was measured by the same method.

(Measurement of outgassing amount) The adhesive tape consisting only of a non-UV curing adhesive layer was prepared by the above method, and the obtained adhesive tape consisting only of a non-UV curing adhesive layer was cut into 5 mm × 5 mm to prepare a measurement sample. The obtained measurement sample was measured by thermal desorption GC-MS, and the obtained gas volume (toluene conversion ppm: μg/g) was set as the outgassing amount. In addition, the measurement tool or measurement conditions used are as follows. Thermal desorption device: TurboMatrix 350, manufactured by PerkinElmer GC-MS device: JMS Q1000, manufactured by NEC Corporation Sample heating conditions: 260℃, 15 min (20 mL/min) Secondary desorption: 350℃, 40 min Flow split: inlet 25 mL/min, outlet 25 mL/min Injection volume: 2.5% Column: EQUITY-1 (non-polar, manufactured by SIGMA-ALDRICH) 0.32 mm×60 m×0.25 μm GC temperature rise: 40℃ (4 min) → temperature rise at a rate of 10℃/min → 300℃ (10 min) He flow rate: 1.5 mL/min Ionization voltage: 70 eV MS measurement range: 29～600 amu (scan 500 ms) MS temperature: ion source temperature 230℃, interface temperature 250℃

(Measurement of adhesive strength) An adhesive tape consisting only of a non-UV curing adhesive layer was prepared by the above method as a test sample. The obtained adhesive tape consisting only of a non-UV curing adhesive layer was cut into 10 mm × 10 mm to prepare a test sample. The obtained test sample was subjected to a probe viscosity measurement. The measurement tool or measurement conditions used are as follows. Adhesion tester: TAC1000, manufactured by RHESCA Probe diameter: 3 mmφ Compression load: 100 g Compression time: 1 second Contact speed: 30 mm·min Peeling speed: 600 mm/min

(Determination of gel fraction) Scrape only 0.1 g of the non-UV curing adhesive layer of the obtained adhesive tape, immerse it in 50 ml of ethyl acetate, and vibrate it for 24 hours at 23 degrees and 120 rpm using a vibrator (hereinafter referred to as the adhesive composition). After vibration, use a metal wire mesh (mesh #200) to separate the ethyl acetate from the adhesive composition that swells after absorbing ethyl acetate. Dry the separated adhesive composition at 110°C for 1 hour. The weight of the adhesive composition including the metal wire mesh after drying was measured, and the gel fraction of the non-UV curing adhesive layer was calculated using the following formula. The results are shown in Tables 1 and 2. Gel fraction (weight %) = 100 × (W ₁ - _{W 2} ) / W ₀ (W ₀ : initial weight of the adhesive composition, W ₁ : weight of the adhesive composition including the metal wire mesh after drying, W ₂ : initial weight of the metal wire mesh)

(Examples 2 to 11, Comparative Examples 1 to 11) The amounts of butyl acrylate, acrylic acid, and silica filler in the non-UV curing adhesive layer were set as shown in Tables 1 and 2, and the weight average molecular weight and molecular weight distribution of the base polymer were changed by changing the polymerization conditions to be as shown in Tables 1 and 2. The adhesive agent was added in the amount shown in Tables 1 and 2. The adhesive tape was produced in the same manner as in Example 1, and the physical properties were measured. As the adhesive agent, UN5500 manufactured by Negami Industries was used. As the isocyanate curing agent, Coronate L manufactured by Tosoh Corporation was used.

<Evaluation> The adhesive tapes obtained in the embodiments and comparative examples were evaluated by the following method. The results are shown in Tables 1 and 2.

(1) Evaluation after heat treatment of substrate The UV-curable adhesive layer side of the adhesive tape was attached to a substrate (TPWB-S02-READCUT, manufactured by Dachang Electronics Co., Ltd.) to obtain a laminate. Then, using a high-pressure mercury UV irradiator, the irradiation intensity was adjusted so that the irradiation intensity on the adhesive tape surface became 100 mW/ ^cm2 , and 365 nm UV rays were irradiated from the non-UV-curable adhesive layer side for 30 seconds to crosslink and harden the UV-curable adhesive layer. Thereafter, the non-UV-curable adhesive layer of the laminate was attached to a CCL support (copper-clad laminate) and heat treated at 260°C for 6 minutes for a total of three times. After the heat treatment, the adhesive tape was peeled off from the substrate. The peeling of the adhesive tape, the bubbling of the non-UV curing adhesive layer, and the paste residue on the substrate were evaluated by the following method.

(Evaluation of adhesive tape peeling) The adhesive tape after heat treatment was visually observed, and the peeling of the adhesive tape was evaluated by setting "○" if there was no peeling or void at the interface between the UV-curing adhesive layer and the substrate, "△" if there was partial peeling or void, and "×" if there was peeling or void on the entire surface.

(Evaluation of the foaming of the non-UV curing adhesive layer) The non-UV curing adhesive layer of the adhesive tape after the heat treatment was visually observed, and the foaming of the non-UV curing adhesive layer was evaluated by setting "◎" for no foaming, "○" for almost no foaming, "△" for partial foaming, and "×" for foaming on the entire surface.

(Evaluation of paste residue on substrate) The substrate after peeling was observed under an optical microscope. No paste residue was marked as "◎", almost no paste residue was marked as "○", partial paste residue was marked as "△", and the entire surface was marked as "×" to evaluate the paste residue on the substrate.

(2) Evaluation of chemical resistance A polyimide film was attached to the UV-curing adhesive layer of the obtained adhesive tape, and a CCL board (copper clad laminate) was attached to the non-UV-curing adhesive layer to prepare a test sample. The obtained test sample was immersed in PINEALPHA (manufactured by Arakawa Chemical Industries, Ltd.) at 70°C for 2 hours and then dried in an oven at 110°C for 1 hour. The weight loss rate before and after immersion was measured. The chemical resistance was evaluated by setting the weight reduction rate before and after immersion to 3.0% or less as "◎", the weight reduction rate to 5.0% or less as "○", the weight reduction rate to 5.0% or less as "△", the weight reduction rate to 8.0% or more or less or less or less as "×".

[Table 1] Embodiment 1 Embodiment 2 Embodiment 3 Embodiment 4 Embodiment 5 Embodiment 6 Embodiment 7 Embodiment 8 Embodiment 9 Embodiment 10 Embodiment 11 Adhesive tape Non-UV curing adhesive layer (A) or (A') base polymer (a) Alkyl (meth)acrylate (wt%) Butyl acrylate 97 Butyl acrylate 97 Butyl acrylate 95 Butyl acrylate 95 Butyl acrylate 94 Butyl acrylate 94 Butyl acrylate 94 Butyl acrylate 92 Butyl acrylate 96 Butyl acrylate 96 Butyl acrylate 96 (b) Carboxyl-containing monomers (wt%) Acrylic 3 Acrylic 3 Acrylic 5 Acrylic 5 Acrylic 6 Acrylic 6 Acrylic 6 Acrylic 8 Acrylic 4 Acrylic 4 Acrylic 4 (c) Weight average molecular weight (Mw) 1 million 800,000 1.2 million 1.2 million 1.9 million 1.9 million 1.9 million 600,000 1.3 million 1.3 million 1.3 million (d) Molecular weight distribution (Mw/Mn) 3 4 2.5 7.8 1.8 3 12.6 2.3 5.5 5.5 5.5 (B) Hardener (weight parts based on 100 parts of base polymer) Epoxy 0.35 Epoxy 0.2 Epoxy 0.15 Epoxy 0.15 Epoxy 0.5 Epoxy 0.5 Epoxy 0.5 Epoxy 0.5 Epoxy 0.06 Epoxy 1.2 Epoxy 0.8 (C) Si filler (weight parts based on 100 parts of base polymer) 10 10 10 10 20 10 30 30 10 45 45 Adhesive agent (weight parts when the base polymer is 100) 0 1 0 30 0 30 0 45 45 0 0 Tensile strength at 23℃ (N/10 mm) 8.0 5.8 7.9 7.2 17.9 13.2 14.9 5.5 6.9 18.3 8.3 Outgassing amount (ppm) 2300 3200 7500 9500 5500 7200 9800 9300 9200 8000 7800 Adhesion strength (gf) 35.8 108.3 164 248.5 8.4 50 37.9 420 120 8.5 9.4 Gel fraction (%) 97 93.3 90.3 85.2 91.2 87.4 90.3 80.3 75 96 94.5 Tensile strength at 23°C before curing (N/10 mm) 4.3 2.8 4.2 3.8 8.5 7.6 8.1 2.6 3.3 9.6 4.1 Reviews Adhesive tape peeling ○ ○ ○ ○ △ ○ ○ ○ ○ △ △ Foaming of non-UV curing adhesive layer ◎ ◎ ○ △ ○ ○ △ △ △ ○ ○ Paste residue on substrate ◎ ○ ○ ○ ○ ○ ○ △ ○ ○ ○ Chemical resistance ◎ ○ ○ ○ ○ ○ ○ ○ × ○ ○

[Table 2] Comparison Example 1 Comparison Example 2 Comparison Example 3 Comparison Example 4 Comparison Example 5 Comparison Example 6 Comparison Example 7 Comparative Example 8 Comparative Example 9 Comparative Example 10 Comparative Example 11 Adhesive tape Non-UV curing adhesive layer (A) or (A') base polymer (a) Alkyl (meth)acrylate (wt%) Butyl acrylate 97 Butyl acrylate 97 Butyl acrylate 97 Butyl acrylate 99 Butyl acrylate 95 Butyl acrylate 95 Butyl acrylate 90 Butyl acrylate 90 Butyl acrylate 98 Butyl acrylate 98 Butyl acrylate 85 (b) Carboxyl-containing monomers (wt%) Acrylic 3 Acrylic 3 Acrylic 3 Acrylic 1 Acrylic 5 Acrylic 5 Acrylic 10 Acrylic 10 Acrylic 2 Acrylic 2 Acrylic 15 (c) Weight average molecular weight (Mw) 1 million 1 million 500,000 470,000 770,000 400,000 2.05 million 2.05 million 1.2 million 1.2 million 2.2 million (d) Molecular weight distribution (Mw/Mn) 8 3 6 11.5 1.7 1.8 12 12 1.8 1.8 5 (B) Hardener (weight parts based on 100 parts of base polymer) Epoxy 0.1 Isocyanate 0.2 Epoxy 0.3 Epoxy 0.05 Epoxy 0.8 Epoxy 0.3 Epoxy 0.2 Epoxy 1.0 Epoxy 0.5 Epoxy 0.05 Epoxy 1.0 (C) Si filler (weight parts based on 100 parts of base polymer) 10 0 10 0 10 15 5 45 45 45 40 Adhesive agent (weight parts when the base polymer is 100) 0 0 1 40 0 15 30 0 0 45 0 Tensile strength at 23℃ (N/10 mm) 4.3 4.1 4.8 3.9 3.2 3.5 13.1 15.2 3.8 2.9 twenty one Outgassing amount (ppm) 58000 40000 42000 61000 35000 42000 30000 25000 8700 15000 8600 Adhesion strength (gf) 148.1 102 173 157.1 94.4 340.5 40 7.8 10.3 180 5.8 Gel fraction (%) 77 0 89 75 89.9 89.6 83.5 94 90 75 96 Tensile strength at 23°C before curing (N/10 mm) 2.1 2.1 2.4 1.7 1.5 1.4 8.5 12 2.1 1.9 9.4 Reviews Adhesive tape peeling △ × △ × △ × △ × × △ × Foaming of non-UV curing adhesive layer × × × × × × × △ △ × △ Paste residue on substrate × × × × × × × × × × △ Chemical resistance × × ○ × ○ ○ ○ ○ ○ × △ Industrial Availability

According to the present invention, an adhesive tape and a method for manufacturing electronic components using the adhesive tape can be provided. The adhesive tape can also be used for an opaque support in the manufacture of electronic components, and can suppress peeling from the adherend and the support or paste residue even when a high temperature treatment is performed.

without

without

Claims (10)

An adhesive tape having a non-UV curing adhesive layer and a UV curing adhesive layer laminated on the non-UV curing adhesive layer, wherein the tensile strength of the non-UV curing adhesive layer at 23°C is greater than 5.0N/10mm and less than 20.0N/10mm, and the outgassing amount of the non-UV curing adhesive layer when heated at 260°C for 15 minutes is less than 10000ppm. For example, in the adhesive tape of claim 1, the adhesive strength of the non-UV curing adhesive layer is 10~300gf/3mmΦ. The adhesive tape of claim 1 or 2, wherein the non-UV curing adhesive layer contains: (A) a (meth) acrylic copolymer as a base polymer, which contains (a) 92-97% by weight of a (meth) acrylic acid alkyl ester having an alkyl group with 4-12 carbon atoms and (b) 3.0-8.0% by weight of a carboxyl group-containing monomer as constituent components, and (c) a weight average molecular weight of 700,000 or more and (d) a molecular weight distribution of 2-6; (B) an epoxy compound containing a tertiary amine structure as a curing agent; and (C) a filler; and the curing agent is contained in an amount of 0.1-0.5 parts by weight and the filler is contained in an amount of 3-20 parts by weight relative to 100 parts by weight of the base polymer. As in the adhesive tape of claim 1 or 2, the non-UV curing adhesive layer contains 30 parts by weight or less of an adhesive imparting agent relative to 100 parts by weight of the (meth)acrylic copolymer. As in the adhesive tape of claim 1 or 2, the UV-curing adhesive layer contains a UV-curing adhesive component and a polysilicone compound, the polysilicone compound has a functional group capable of crosslinking with the UV-curing adhesive component and has a weight average molecular weight of 300 to 50,000. As in the adhesive tape of claim 1 or 2, the gel fraction of the non-UV curing adhesive layer is 80% or more. For adhesive tapes in claim 1 or 2, the tensile strength at 23°C before curing is 2.5~10N/10mm. An adhesive tape having a non-UV curing adhesive layer and a UV curing adhesive layer laminated on the non-UV curing adhesive layer, wherein the non-UV curing adhesive layer has a gas release amount of less than 10,000 ppm when heated at 260°C for 15 minutes, and the non-UV curing adhesive layer contains: (A') a (meth) acrylic copolymer as a base polymer, which contains 92 to 97% by weight of a (meth) acrylic acid alkyl ester having an alkyl group with 4 to 12 carbon atoms as a constituent component; (B) an epoxy compound containing a tertiary amine structure as a curing agent; and (C) a filler. The adhesive tape of claim 1, 2 or 8 is used in a method for manufacturing electronic components, which comprises the following steps: an adherend attaching step, which is to attach the adherend from the UV-curing adhesive layer; a curing step, which is to irradiate UV rays to harden the UV-curing adhesive layer; a support attaching step, which is to attach the support to the non-UV-curing adhesive layer; a heat treatment step, which is to treat the adherend at a high temperature of more than 150°C; and a peeling step, which is to peel the adherend from the adhesive tape. A method for manufacturing electronic components, comprising the following steps: an adherend attaching step, which is to attach the adhesive tape of claim 1, 2, 3, 4, 5, 6, 7, 8 or 9 to the adherend from the above-mentioned UV-curing adhesive layer; a curing step, which is to irradiate UV rays to cure the above-mentioned UV-curing adhesive layer; a support attaching step, which is to attach the support to the above-mentioned non-UV-curing adhesive layer; a heat treatment step, which is to treat the above-mentioned adherend at a high temperature of more than 150°C; and a peeling step, which is to peel the above-mentioned adherend from the above-mentioned adhesive tape.