Pressure-sensitive adhesive tape for semiconductor processing, and method for producing semiconductor

Abstract

A purpose of the present invention is to provide a pressure-sensitive adhesive tape for semiconductor processing which is excellent in terms of antistatic performance and transparency and which, even after having undergone a high-temperature treatment, can be easily removed. Another purpose is to provide a method for producing a semiconductor using the pressure-sensitive adhesive tape for semiconductor processing. This pressure-sensitive adhesive tape for semiconductor processing comprises a pressure-sensitive adhesive layer, an electroconductive layer, and a substrate in this order, wherein the pressure-sensitive adhesive layer includes a photocurable pressure-sensitive adhesive. The pressure-sensitive adhesive tape for semiconductor processing has a visible-light transmittance determined from the pressure-sensitive adhesive layer side of 50% or greater. When the pressure-sensitive adhesive tape for semiconductor processing is applied to a silicon wafer and then irradiated with light having a wavelength of 405 nm at an integrated irradiance of 3,000 mJ / cm2, then the pressure-sensitive adhesive tape for semiconductor processing has a 180° peel force, as measured at 23°C and a peeling rate of 300 mm / min, of less than 0.15 N / 25 mm. When the pressure-sensitive adhesive tape for semiconductor processing is applied to a silicon wafer and then irradiated with light having a wavelength of 405 nm at an integrated irradiance of 3,000 mJ / cm2 and the pressure-sensitive adhesive tape for semiconductor processing is thereafter heated at 260°C for five minutes and then heated at 180°C for three hours, then the pressure-sensitive adhesive tape for semiconductor processing has a 180° peel force, as measured at 23°C and a peeling rate of 300 mm / min, of 0.5 N / 25 mm or less.

Description

Adhesive tape for semiconductor processing and semiconductor manufacturing method

[0001] The present invention relates to an adhesive tape for semiconductor processing, and also to a method for manufacturing a semiconductor using the adhesive tape for semiconductor processing.

[0002] During processing of electronic components such as semiconductors, in order to facilitate handling of the electronic components and prevent damage, the electronic components are protected by being fixed to a support via a temporary fixing material made of a pressure-sensitive adhesive composition or by being attached to the electronic components by a tape-like temporary fixing material having a pressure-sensitive adhesive layer. For example, when a thick-film wafer cut from a high-purity silicon single crystal or the like is ground to a predetermined thickness to form a thin-film wafer, the thick-film wafer is adhered to a support via a temporary fixing material.

[0003] Thus, temporary fixing materials used for temporarily fixing electronic components are required to have high adhesiveness sufficient to firmly fix the electronic components during the processing step, and also to be able to be peeled off without damaging the electronic components after the processing step is completed (hereinafter also referred to as "high adhesion and easy peeling"). As a means for achieving high adhesion and easy peeling, for example, Patent Document 1 discloses a pressure-sensitive adhesive sheet using a pressure-sensitive adhesive in which a polyfunctional monomer or oligomer having a radiation-polymerizable functional group is bonded to the side chain or main chain of the polymer. By utilizing the fact that the polymer has a radiation-polymerizable functional group, which hardens when irradiated with ultraviolet light, the adhesive strength is reduced by irradiating ultraviolet light during peeling, allowing peeling without leaving any adhesive residue.

[0004] Furthermore, pressure-sensitive adhesive tapes used in the manufacturing process of semiconductor devices are required to have excellent antistatic properties to prevent circuits from being damaged by static electricity. Known examples of pressure-sensitive adhesive tapes with excellent antistatic properties include antistatic pressure-sensitive adhesive tapes in which a conductive filler is dispersed in the pressure-sensitive adhesive layer (see, for example, Patent Documents 2 to 4).

[0005] Japanese Patent Laid-Open No. 5-32946 Japanese Patent Laid-Open No. 2012-007093 Japanese Patent Laid-Open No. 9-207259 Japanese Patent Laid-Open No. 2016-089021

[0006] In the manufacturing process of semiconductor devices, the circuit pattern of the semiconductor device is often recognized from the adhesive tape side for positioning during processing, and therefore, adhesive tapes are also required to have excellent transparency. However, conventional antistatic adhesive tapes have low transparency when they are blended with a conductive filler to the extent that they provide sufficient antistatic performance. When such an adhesive tape with low transparency is applied to a semiconductor device, the circuit pattern on the semiconductor device cannot be recognized through the adhesive tape, which can cause a problem of difficult process control.

[0007] Furthermore, with the recent advances in semiconductor device performance, high-temperature processing has become common on the surface of semiconductor devices. For example, as a next-generation technology, 3D stacking technology using TSVs (Through Silicon Vias), which stack multiple semiconductor chips to dramatically improve device performance and miniaturize devices, is attracting attention. TSVs not only enable higher-density semiconductor packaging, but also enable shorter connection distances, thereby reducing noise and resistance, dramatically increasing access speeds, and providing excellent heat dissipation during use. The manufacture of such TSVs requires high-temperature processing, such as bumping the ground thin-film wafer, forming bumps on the backside, and reflowing during 3D stacking. However, conventional antistatic adhesive tapes suffer from a significant decrease in their antistatic performance when subjected to high-temperature processing, which can lead to cracks on the semiconductor surface when the adhesive tape is peeled from the semiconductor. Furthermore, the adhesive tape's increased adhesion to the adherend can result in insufficient reduction in adhesive strength upon peeling, resulting in the problem of adhesive residue remaining on the adherend.

[0008] An object of the present invention is to provide an adhesive tape for semiconductor processing that has excellent anti-static properties and transparency and that can be easily peeled even after high-temperature treatment. Another object of the present invention is to provide a method for manufacturing semiconductors that uses the adhesive tape for semiconductor processing.

[0009] Disclosure 1 provides a semiconductor processing adhesive tape having an adhesive layer, a conductive layer, and a substrate in this order, the adhesive layer containing a photocurable adhesive, the adhesive layer having a visible light transmittance of 50% or more as measured from the adhesive layer side, and after the semiconductor processing adhesive tape is bonded to a silicon wafer, the semiconductor processing adhesive tape is irradiated with light having a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm. ２ When irradiated with light having a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm, the 180° peel strength of the adhesive tape for semiconductor processing is less than 0.15 N / 25 mm at 23°C and a peeling speed of 300 mm / min, and after the adhesive tape for semiconductor processing is laminated to a silicon wafer, the adhesive tape for semiconductor processing is irradiated with light having a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm ２ The present disclosure 2 is a semiconductor processing adhesive tape in which the 180° peel strength of the semiconductor processing adhesive tape is 0.5 N / 25 mm or less at 23°C and a peel rate of 300 mm / min after irradiating the semiconductor processing adhesive tape with light of a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm2 with the semiconductor processing adhesive tape, and then further heating the semiconductor processing adhesive tape at 260°C for 5 minutes and then at 180°C for 3 hours. ２ After irradiation with light, the surface resistivity of the adhesive layer side of the adhesive tape for semiconductor processing is R １ Ω / □, and the semiconductor processing adhesive tape was irradiated with light of wavelength 405 nm at an integrated illuminance of 3000 mJ / cm ２ After irradiation with 1000 kJ / cm 3 , the adhesive tape was further heated at 260° C. for 5 minutes, and then further heated at 180° C. for 3 hours. The surface resistivity of the adhesive layer side of the adhesive tape for semiconductor processing was then measured. ２ When Ω / □ is used, the above R １ and the above R ２ Both are 1.0 x 10 １４ Ω / □ or less, and the rate of change R in the surface resistivity of the pressure-sensitive adhesive layer side of the pressure-sensitive adhesive tape for semiconductor processing before and after heating ２ / R １The semiconductor processing adhesive tape of Disclosure 1, wherein the photocurable adhesive contains a filler. Disclosure 4 is the semiconductor processing adhesive tape of Disclosure 1, 2, or 3, wherein the photocurable adhesive contains a release agent. Disclosure 5 is the semiconductor processing adhesive tape of Disclosure 1, 2, 3, or 4, wherein the adhesive layer has a thickness of 10 μm or more and 300 μm or less. Disclosure 6 is the semiconductor processing adhesive tape of Disclosure 1, 2, 3, 4, or 5, wherein the conductive layer contains an organic layer. Disclosure 7 is the semiconductor processing adhesive tape of Disclosure 1, 2, 3, 4, 5, or 6, wherein the conductive layer contains a conductive polymer. Disclosure 8 is the semiconductor processing adhesive tape of Disclosure 7, wherein the conductive polymer contains a polythiophene-based polymer. Disclosure 9 is the pressure-sensitive adhesive tape for semiconductor processing according to Disclosure 1, 2, 3, 4, 5, 6, 7, or 8, wherein the conductive layer has a total thickness of 0.001 μm or more and 1 μm or less. Disclosure 10 is the pressure-sensitive adhesive tape for semiconductor processing according to Disclosure 1, 2, 3, 4, 5, 6, 7, 8, or 9, wherein the base material contains a resin (A1) having in its main chain skeleton a repeating unit containing at least one kind selected from the group consisting of an ether bond, a ketone group, and an ester bond. Disclosure 11 is the pressure-sensitive adhesive tape for semiconductor processing according to Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, wherein the pressure-sensitive adhesive tape for semiconductor processing has a thermal weight loss rate at 260°C of 10% or less. The present disclosure 12 is a method for manufacturing a semiconductor, comprising the steps of attaching the adhesive tape for semiconductor processing according to the present disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 to a semiconductor device to produce a laminate, heating the laminate, and peeling the adhesive tape for semiconductor processing from the laminate.

[0010] The present inventors have investigated the use of a semiconductor processing adhesive tape having, in that order, an adhesive layer, a conductive layer, and a substrate, and have investigated the adjustment of the visible light transmittance of the semiconductor processing adhesive tape, the 180° peel strength of the semiconductor processing adhesive tape after irradiating the semiconductor processing adhesive tape with light, and the 180° peel strength of the semiconductor processing adhesive tape after irradiating the semiconductor processing adhesive tape with light and then heating, within specific ranges. As a result, they have found that a semiconductor processing adhesive tape having excellent antistatic properties and transparency and which can be easily peeled even after high-temperature treatment can be obtained, and have completed the present invention.

[0011] The semiconductor processing adhesive tape of the present invention has an adhesive layer, a conductive layer, and a substrate, in this order. Conventionally, a method for improving the antistatic performance of an adhesive tape includes incorporating an antistatic agent into the adhesive layer. However, this method poses a problem of residue being generated on the semiconductor when the adhesive tape is peeled off. On the other hand, the semiconductor processing adhesive tape includes the conductive layer, which has excellent antistatic performance, as a layer separate from the adhesive layer, thereby preventing residue from being generated on the adherend when the semiconductor processing adhesive tape is peeled off, and allowing for easy peeling. Furthermore, when the adhesive tape has the conductive layer on its outermost surface, subjecting the adhesive tape to high-temperature treatment reduces the antistatic performance, resulting in the problem of cracks occurring on the semiconductor surface when the adhesive tape is peeled off from the semiconductor. On the other hand, the semiconductor processing adhesive tape does not have the conductive layer on its outermost surface, thereby preventing cracks from occurring on the semiconductor surface when the adhesive tape is peeled off from the semiconductor after high-temperature treatment. Therefore, by having the adhesive layer, conductive layer, and substrate in this order, the semiconductor processing adhesive tape of the present invention can be made to have excellent anti-static properties and can be easily peeled even after high-temperature treatment. Therefore, the semiconductor processing adhesive tape can suppress the generation of cracks on the semiconductor surface when the adhesive tape is peeled from the semiconductor after high-temperature treatment, and the generation of residues on the semiconductor when the adhesive tape is peeled from the semiconductor.

[0012] The pressure-sensitive adhesive layer contains a photocurable pressure-sensitive adhesive. By containing the photocurable pressure-sensitive adhesive layer, the adhesive layer can be cured by irradiation with light, which reduces adhesive residue when the semiconductor processing pressure-sensitive adhesive tape attached to the circuit surface of a semiconductor device on which a circuit is formed is peeled off, making it easy to peel. Examples of the photocurable pressure-sensitive adhesive include pressure-sensitive adhesives containing a polymerizable polymer as a main component and, if necessary, a photopolymerization initiator as a polymerization initiator.

[0013] The polymerizable polymer can be obtained, for example, by the following method. That is, first, a (meth)acrylic polymer having a functional group in the molecule (hereinafter also referred to as a "functional group-containing (meth)acrylic polymer") is synthesized in advance. Next, the functional group-containing (meth)acrylic polymer is reacted with a compound having a functional group reactive with the functional group and a radically polymerizable unsaturated bond in the molecule (hereinafter also referred to as a "functional group-containing unsaturated compound") to obtain a polymerizable polymer. In this specification, "(meth)acrylic" means acrylic or methacrylic.

[0014] The functional group-containing (meth)acrylic polymer is a polymer that exhibits adhesiveness at room temperature and can be obtained by the same method as that for general (meth)acrylic polymers. Specifically, it is obtained by copolymerizing a (meth)acrylic acid alkyl ester, in which the ester-terminated alkyl group has 2 to 18 carbon atoms, as the main monomer with a functional group-containing monomer and, if necessary, with other modifying monomers copolymerizable therewith, by a conventional method. The weight-average molecular weight of the functional group-containing (meth)acrylic polymer is typically about 200,000 to 2,000,000. In this specification, the term "ester-terminated alkyl group" refers to the alkyl group bonded to the oxygen atom of the ester bond in the (meth)acrylic acid alkyl ester.

[0015] Examples of the functional group-containing monomer include carboxy group-containing monomers such as (meth)acrylic acid, hydroxy group-containing monomers such as hydroxyethyl (meth)acrylate, epoxy group-containing monomers such as glycidyl (meth)acrylate, isocyanate group-containing monomers such as isocyanatoethyl (meth)acrylate, amino group-containing monomers such as aminoethyl (meth)acrylate, and nitrile group-containing monomers such as (meth)acrylonitrile.

[0016] Examples of the other copolymerizable modifying monomers include various monomers used in general (meth)acrylic polymers, such as vinyl acetate and styrene.

[0017] As the functional group-containing unsaturated compound to be reacted with the functional group-containing (meth)acrylic polymer, the same functional group-containing monomers as those described above can be used depending on 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 carboxy group, an epoxy group-containing monomer or an isocyanate group-containing monomer is used. When the functional group is a hydroxyl group, an isocyanate group-containing monomer is used. When the functional group is an epoxy group, a carboxy group-containing monomer or an amide group-containing monomer such as acrylamide is used. When the functional group is an amino group, an epoxy group-containing monomer is used.

[0018] The weight-average molecular weight of the polymerizable polymer preferably has a lower limit of 200,000 and a preferred upper limit of 2,000,000. When the weight-average molecular weight of the polymerizable polymer is within the above range, the pressure-sensitive adhesive layer does not become too hard, and the resulting pressure-sensitive adhesive tape has excellent embedding properties for uneven surfaces and sufficient initial adhesive strength. The weight-average molecular weight of the polymerizable polymer more preferably has a lower limit of 300,000, a more preferred upper limit of 1,500,000, an even more preferred lower limit of 400,000, and an even more preferred upper limit of 1,000,000. The weight-average molecular weight of the polymerizable polymer in this specification is measured as a polystyrene-equivalent molecular weight by gel permeation chromatography (GPC). Specifically, for example, it can be measured using an APC system (manufactured by Waters Corporation) under the following conditions: a mobile phase of THF, a flow rate of 1.0 mL / min, a column temperature of 40°C, a sample concentration of 0.2% by mass, and an RI-PDA detector. The column may be, for example, HR-MB-M 6.0×150 mm (manufactured by Waters Corporation).

[0019] In the photocurable pressure-sensitive adhesive, the preferred lower limit of the content of the polymerizable polymer is 0.1% by mass, and the preferred upper limit is 25% by mass. When the content of the polymerizable polymer is within the above range, the pressure-sensitive adhesive layer is sufficiently cured and maintains appropriate flexibility even after curing, so that the resulting pressure-sensitive adhesive tape has better peeling performance. The more preferred lower limit of the content of the polymerizable polymer is 0.5% by mass, and the more preferred upper limit is 20% by mass, and even more preferred lower limit is 1% by mass, and even more preferred upper limit is 15% by mass.

[0020] Examples of the photopolymerization initiator include those that are activated by irradiation with light having a wavelength of 250 to 800 nm. Examples of such photopolymerization initiators include acetophenone derivative compounds, benzoin ether compounds, ketal derivative compounds, phosphine oxide derivative compounds, and bis(η5-cyclopentadienyl)titanocene derivative compounds. Examples of the acetophenone derivative compounds include methoxyacetophenone. Examples of the benzoin ether compounds include benzoin propyl ether and benzoin isobutyl ether. Examples of the ketal derivative compounds include benzyl dimethyl ketal and acetophenone diethyl ketal. Examples of the phosphine oxide derivative compounds include 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide. Examples of the bis(η5-cyclopentadienyl)titanocene derivative compound include bis(cyclopentadienyl)-di-phenyl-titanium and bis(cyclopentadienyl)-di-chloro-titanium. Other examples of the photopolymerization initiator include photoradical polymerization initiators such as benzophenone, Michler's ketone, chlorothioxanthone, todecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, α-hydroxycyclohexylphenyl ketone, and 2-hydroxymethylphenylpropane. These photopolymerization initiators may be used alone or in combination of two or more.

[0021] The content of the photopolymerization initiator is preferably 0.1 parts by mass or less and 20 parts by mass or less per 100 parts by mass of the polymerizable polymer. When the content of the photopolymerization initiator is within this range, the entire photocurable adhesive undergoes uniform and rapid polymerization and crosslinking upon irradiation with light, increasing the elastic modulus, thereby significantly reducing the adhesive strength of the resulting semiconductor processing adhesive tape, preventing increased adhesion and the generation of adhesive residue upon peeling. The content of the photopolymerization initiator is more preferably 0.5 parts by mass or less, more preferably 15 parts by mass or less, even more preferably 1 part by mass or less, and even more preferably 10 parts by mass or less.

[0022] The photocurable adhesive preferably contains a filler, which prevents the resulting adhesive tape for semiconductor processing from decreasing in elastic modulus at high temperatures and further prevents peeling during high-temperature treatment, even when the tape is subjected to high-temperature treatment at 300°C or higher.

[0023] Examples of the filler include at least one filler selected from the group consisting of oxides of silicon, titanium, aluminum, calcium, boron, magnesium, and zirconia, silica, talc, and composites thereof. Among these, silica and talc are preferred because they are commercially available at low cost and easily available.

[0024] The filler may be surface-modified. Examples of the functional group that may be used to modify the surface of the filler include an alkylsilane group, a methacryloyl group, and a dimethylsiloxane group. Among these, a dimethylsiloxane group is preferred because it has appropriate hydrophobicity.

[0025] The preferred lower limit of the average particle size of the filler is 0.05 μm, and the preferred upper limit is 3.0 μm. By having the average particle size of the filler within this range, peeling of the resulting adhesive tape for semiconductor processing during high-temperature treatment can be further suppressed, and upon peeling, the tape can be easily peeled by peel treatment. The more preferred lower limit of the average particle size of the filler is 0.1 μm, the more preferred upper limit is 2.0 μm, the even more preferred lower limit is 0.3 μm, and the even more preferred upper limit is 1.5 μm. The average particle size can be determined, for example, by observing 50 random fillers with an electron microscope or an optical microscope and calculating the average particle size of each filler, or by performing laser diffraction particle size distribution measurement.

[0026] The content of the filler is preferably 1 part by mass at the lower limit and 40 parts by mass at the upper limit relative to 100 parts by mass of the polymerizable polymer. By having the filler content within this range, the resulting adhesive tape for semiconductor processing can be more effectively prevented from peeling during high-temperature treatment and can be more easily peeled. The lower limit of the filler content is more preferably 2 parts by mass, and the upper limit is more preferably 30 parts by mass, and even more preferably 3 parts by mass, and even more preferably 20 parts by mass.

[0027] The photocurable adhesive preferably contains a release agent. By including a release agent in the photocurable adhesive, the release agent bleeds out to the adherend interface, making it easier to peel off the resulting semiconductor processing adhesive tape. Examples of the release agent include silicone-based release agents and fluorine-based release agents. These release agents have excellent heat resistance, so by including a release agent in the photocurable adhesive, it is possible to prevent the adhesive layer from burning even after high-temperature treatment at 300°C or higher. Furthermore, when peeling off the semiconductor processing adhesive tape, the release agent bleeds out to the adherend interface, making peeling easier. Among these, silicone-based release agents are preferred from the standpoints of environmental friendliness and ease of disposal.

[0028] The release agent preferably has a functional group crosslinkable with the polymerizable polymer. When the release agent has a functional group crosslinkable with the polymerizable polymer, the release agent is incorporated into the photocurable pressure-sensitive adhesive upon irradiation with light. This prevents the release agent from adhering to and contaminating the adherend. Examples of functional groups crosslinkable with the polymerizable polymer include carboxy groups, functional groups having radically polymerizable unsaturated bonds (e.g., vinyl groups, (meth)acryloyl groups, and optionally substituted maleimide groups), hydroxyl groups, amide groups, isocyanate groups, and epoxy groups.

[0029] Examples of the silicone-based release agent include silicone oil, silicone diacrylate, and silicone-based graft copolymer. Among these, silicone compounds having a functional group crosslinkable with the polymerizable polymer are preferred, and silicone compounds having a siloxane skeleton in the main chain and a functional group crosslinkable with the polymerizable polymer at a side chain or terminal are preferred. Specifically, silicone compounds having a siloxane skeleton in the main chain and a functional group having a carbon-carbon double bond at a side chain or terminal are preferred. As the silicone compound having a siloxane skeleton in the main chain and a functional group having a carbon-carbon double bond at a side chain or terminal, at least one selected from the group consisting of silicone compounds represented by the following formula (1-1), silicone compounds represented by the following formula (1-2), and silicone compounds represented by the following formula (1-3) are preferred. These silicone compounds have particularly excellent heat resistance and are highly polar, so they easily bleed out from the pressure-sensitive adhesive layer.

[0030]

[0031] X in the above formulas (1-1) to (1-3) and Y in the above formulas (1-1) and (1-3) each independently represent an integer of 0 or more and 1200 or less, and R in the above formulas (1-1) to (1-3) represents a functional group having a carbon-carbon double bond.

[0032] In the above formulas (1-1) to (1-3), examples of the functional group having a carbon-carbon double bond represented by R include an optionally substituted maleimide group, a citraconic imide group, a vinyl ether group, an allyl group, and a (meth)acryloyl group. Among these, an optionally substituted maleimide group is preferred because the resulting PSA film has better heat resistance. In addition, when multiple R are present in the above formulas (1-1) to (1-3), the respective R may be the same or different. In addition, in the above formulas (1-1) to (1-3), the carbon-carbon double bond in the functional group having a carbon-carbon double bond represented by R does not include a carbon-carbon double bond constituting an aromatic ring.

[0033] Among the silicone compounds represented by the above formulas (1-1) to (1-3), commercially available examples include EBECRYL350 and EBECRYL1360 (both manufactured by Daicel-Allnex Co., Ltd.), etc. Other examples include BYK-UV3500 (manufactured by BYK-Chemie Co., Ltd.) and TEGO RAD2250 (manufactured by Evonik Co., Ltd.) (in both cases, R is an acryloyl group).

[0034] Examples of the fluorine-based release agent include fluorine compounds such as hydrocarbon compounds having fluorine atoms.

[0035] The content of the release agent is preferably 1 part by mass at its lower limit and 50 parts by mass at its upper limit relative to 100 parts by mass of the polymerizable polymer. When the content of the release agent is within this range, the resulting semiconductor processing pressure-sensitive adhesive tape can be more easily peeled off without contaminating the adherend. From the viewpoint of suppressing contamination while still allowing for easier peeling, the lower limit of the release agent content is more preferably 2 parts by mass, and the upper limit is more preferably 40 parts by mass. Since the semiconductor processing pressure-sensitive adhesive tape has excellent heat resistance, it can exert sufficient effects even when the content of the release agent is relatively small. Therefore, the possibility of contamination by the silicone compound or fluorine compound can be further reduced.

[0036] The photocurable adhesive preferably contains a curing agent. By containing a curing agent, the polymerizable polymer is more likely to form a crosslinked structure, resulting in sufficient initial adhesive strength when applied. Furthermore, since the adhesive strength is likely to decrease significantly when the photocurable adhesive is cured, the resulting adhesive tape for semiconductor processing has excellent peeling performance.

[0037] Examples of the curing agent include isocyanate-based curing agents, aziridine-based curing agents, epoxy-based curing agents, metal chelate-based curing agents, etc. Among these, isocyanate-based curing agents are preferred from the viewpoints of fast reaction rate and further improving the cohesive strength of the pressure-sensitive adhesive layer.

[0038] The preferred lower limit of the curing agent content is 0.05 parts by mass and the preferred upper limit is 10 parts by mass per 100 parts by mass of the polymerizable polymer. By using a curing agent content within the above range, the polymerizable polymer can form a moderately crosslinked structure, and the resulting adhesive tape for semiconductor processing has sufficient initial adhesive strength. The more preferred lower limit of the curing agent content is 0.1 parts by mass, the more preferred upper limit is 5 parts by mass, the even more preferred lower limit is 0.2 parts by mass, and the even more preferred upper limit is 3 parts by mass.

[0039] The photocurable pressure-sensitive adhesive preferably contains a radically polymerizable polyfunctional oligomer or monomer. By containing a radically polymerizable polyfunctional oligomer or monomer, the photocurability of the photocurable pressure-sensitive adhesive is further improved. The polyfunctional oligomer or monomer preferably has a molecular weight of 10,000 or less, and more preferably has a molecular weight of 5,000 or less and 2 to 20 radically polymerizable unsaturated bonds in the molecule, so that the photocurable pressure-sensitive adhesive efficiently undergoes three-dimensional reticulation upon irradiation with light.

[0040] Examples of the polyfunctional oligomer or monomer include trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, and commercially available oligoester (meth)acrylates. These polyfunctional oligomers or monomers may be used alone or in combination of two or more. In this specification, "(meth)acrylate" means acrylate or methacrylate.

[0041] The content of the polyfunctional oligomer or monomer is preferably 1 part by mass at the lower limit and 50 parts by mass at the upper limit relative to 100 parts by mass of the polymerizable polymer. By having the content of the polyfunctional oligomer or monomer within this range, the photocurability of the photocurable pressure-sensitive adhesive is further improved. The content of the polyfunctional oligomer or monomer is more preferably 2 parts by mass at the lower limit and 40 parts by mass at the upper limit, and even more preferably 3 parts by mass at the lower limit and 30 parts by mass at the upper limit.

[0042] The photocurable adhesive may further contain a gas generating agent that generates gas in response to a stimulus. When the photocurable adhesive contains the gas generating agent, the pressure-sensitive adhesive tape for semiconductor processing can be peeled off more easily and without leaving any adhesive residue by applying a stimulus to the pressure-sensitive adhesive tape for semiconductor processing to generate gas from the gas generating agent when peeling the pressure-sensitive adhesive tape for semiconductor processing from the adherend.

[0043] Preferred examples of the gas generating agent include carboxylic acid compounds such as phenylacetic acid, diphenylacetic acid, and triphenylacetic acid, and salts thereof, and tetrazole compounds such as 1H-tetrazole, 5-phenyl-1H-tetrazole, and 5,5-azobis-1H-tetrazole, and salts thereof. Such gas generating agents generate gas when irradiated with light such as ultraviolet light, and have high heat resistance such that they do not decompose even at high temperatures of about 200°C.

[0044] The content of the gas generating agent is preferably 5 parts by mass or less and 50 parts by mass or less per 100 parts by mass of the polymerizable polymer. By having the content of the polymerizable polymer within this range, the resulting adhesive tape for semiconductor processing can be more easily peeled. The more preferred lower limit of the content of the gas generating agent is 8 parts by mass or less and the more preferred upper limit is 30 parts by mass or less.

[0045] When the photocurable pressure-sensitive adhesive contains the gas-generating agent, it may further contain a photosensitizer. The photosensitizer has the effect of amplifying the light stimulation of the gas-generating agent, so that the gas can be released with less light irradiation. Furthermore, the gas can be released with light of a wider wavelength range.

[0046] The photocurable adhesive may contain known additives such as heat stabilizers, antioxidants, plasticizers, surfactants, waxes, etc., as long as the effects of the present invention are not impaired.

[0047] The thickness of the pressure-sensitive adhesive layer preferably has a lower limit of 10 μm and an upper limit of 300 μm. When the thickness of the pressure-sensitive adhesive layer is within the above range, the adherend can be protected with sufficient adhesive strength and adhesive residue upon peeling can be suppressed. From the viewpoint of further improving the adhesive strength of the resulting semiconductor processing adhesive tape and further suppressing adhesive residue upon peeling, the thickness of the pressure-sensitive adhesive layer is more preferably 20 μm lower limit, more preferably 200 μm upper limit, even more preferably 30 μm lower limit, and even more preferably 150 μm upper limit.

[0048] The semiconductor processing adhesive tape of the present invention has a conductive layer. By having the conductive layer, the surface resistivity of the adhesive layer side can be adjusted within a certain range while maintaining transparency. Furthermore, high anti-static performance can be achieved even when subjected to high-temperature treatment. The transparency and surface resistivity of the semiconductor processing adhesive tape can be freely adjusted by adjusting the type of conductive polymer contained in the conductive layer, the type of metal or the like constituting the conductive layer, the thickness of the conductive layer, the area of ​​the conductive layer, etc. Furthermore, the conductive layer may be a single layer or multiple layers.

[0049] The conductive layer is not particularly limited and may be an organic layer or an inorganic layer. In particular, it is preferable that the conductive layer contains an organic layer, from the viewpoint of further improving the transparency of the obtained pressure-sensitive adhesive tape and further suppressing contamination of the adherend by suppressing the outflow of metal ions derived from the conductive layer. Furthermore, the conductive layer may be configured such that an organic layer is further formed on the surface of an inorganic layer, or such that an inorganic layer is further formed on the surface of an organic layer.

[0050] The conductive layer preferably contains a conductive polymer. By including the conductive polymer in the conductive layer, contamination of the adherend by metal ions can be further suppressed. When the conductive layer contains the conductive polymer, the organic layer may have a layer composed of the conductive polymer, or the conductive polymer may be contained in the inorganic layer composed of a metal, alloy, metal compound, or the like described below.

[0051] Examples of the conductive polymer include organic compounds such as polythiophene-based polymers, carbon black, and carbon nanotubes. Among these, polythiophene-based polymers are preferred because they have high transparency and allow the photocurable pressure-sensitive adhesive to be irradiated with light more efficiently.

[0052] Examples of the polythiophene polymer include a polymer (PEDOT / PSS) synthesized from poly(3,4-ethylenedioxythiophene) (PEDOT) and polystyrene sulfonic acid (PSS).

[0053] The weight-average molecular weight of the conductive polymer preferably has a lower limit of 10,000 and a higher limit of 400,000. By having the weight-average molecular weight of the conductive polymer within this range, the surface resistivity of the resulting adhesive tape for semiconductor processing can be further reduced, resulting in superior charge suppression performance. The weight-average molecular weight of the conductive polymer more preferably has a lower limit of 50,000 and a higher limit of 350,000, an even more preferred lower limit of 100,000, and an even more preferred upper limit of 300,000. Note that the weight-average molecular weight of the conductive polymer in this specification is measured as a polystyrene-equivalent molecular weight by gel permeation chromatography (GPC). Specifically, for example, it can be measured using an APC system (manufactured by Waters Corporation) under the following conditions: a mobile phase of THF, a flow rate of 1.0 mL / min, a column temperature of 40°C, a sample concentration of 0.2% by mass, and an RI-PDA detector. The column that can be used is, for example, an HR-MB-M 6.0 x 150 mm (manufactured by Waters Corporation).

[0054] Examples of the organic layer include a layer made of the conductive polymer described above and a layer made of a surfactant.

[0055] Examples of the inorganic layer include layers composed of metal oxides, metals, alloys, metal compounds, etc. Among these, when the conductive layer is the inorganic layer, it is preferable to have a layer composed of a metal, alloy, or metal compound, from the viewpoint that the thickness of the conductive layer can be easily adjusted and the transparency and surface resistivity of the obtained adhesive tape for semiconductor processing can be easily improved. Note that the metal, alloy, and metal compound may be used alone or in combination of two or more.

[0056] When the conductive layer includes the inorganic layer, examples of the metal constituting the conductive layer include gold, silver, copper, platinum, titanium, aluminum, tin, etc. When the conductive layer has a layer composed of a metal, the layer composed of the metal may be a single layer or multiple layers.

[0057] When the conductive layer includes the inorganic layer, examples of the alloy constituting the conductive layer include an alloy containing iron, an alloy containing molybdenum, and an alloy containing nickel and copper, such as Monel. When the conductive layer has a layer made of an alloy, the layer made of the alloy may be a single layer or multiple layers.

[0058] Examples of the iron-containing alloy include an alloy containing chromium and iron, and an alloy containing chromium, nickel, and iron, specifically stainless steel (SUS). Specific examples of the stainless steel (SUS) include stainless steel (SUS201), stainless steel (SUS202), stainless steel (SUS301), stainless steel (SUS302), stainless steel (SUS303), stainless steel (SUS304), stainless steel (SUS306), stainless steel (SUS310S), stainless steel (SUS316), stainless steel (SUS317), stainless steel (SUS329J11), stainless steel (SUS403), stainless steel (SUS405), stainless steel (SUS420), stainless steel (SUS430), stainless steel (SUS430LX), and stainless steel (SUS6330).

[0059] The molybdenum-containing alloy is not particularly limited as long as it contains molybdenum, but it preferably further contains nickel and chromium from the viewpoints of further improving corrosion resistance and further suppressing deterioration of anti-static properties over time. The molybdenum content of the molybdenum-containing alloy is preferably 5% by mass at the lower limit and 30% by mass at the upper limit. A molybdenum content of 5% by mass or more can more easily achieve both anti-static properties and transparency of the semiconductor processing adhesive tape. Furthermore, a molybdenum content of 30% by mass or less can more easily adjust the surface resistivity of the resulting semiconductor processing adhesive tape. The molybdenum content is more preferably 7% by mass at the lower limit, more preferably 25% by mass at the upper limit, even more preferably 9% by mass at the lower limit, even more preferably 20% by mass at the upper limit, even more preferably 11% by mass at the lower limit, particularly preferably 13% by mass at the lower limit, very preferably 15% by mass at the lower limit, and most preferably 16% by mass at the lower limit. When the molybdenum-containing alloy contains nickel and chromium, the molybdenum content is preferably 5% by mass, the nickel content is preferably 40% by mass, and the chromium content is preferably 1% by mass, from the viewpoint of further improving the corrosion resistance of the resulting adhesive tape for semiconductor processing and further suppressing deterioration of the charge suppressing performance over time. Specific examples of the molybdenum-containing alloy include Hastelloy (registered trademark), Inconel (registered trademark), Carpenter (registered trademark), Incoloy (registered trademark), and the like.

[0060] Specific examples of Hastelloy (registered trademark) include Hastelloy (HASTELLOY B-2), Hastelloy (HASTELLOY B-3), Hastelloy (HASTELLOY C-4), Hastelloy (HASTELLOY C-2000), Hastelloy (HASTELLOY C-22), Hastelloy (HASTELLOY C-276), Hastelloy (HASTELLOY G-30), Hastelloy (HASTELLOY N), Hastelloy (HASTELLOY W), Hastelloy (HASTELLOY X), and the like.

[0061] Specific examples of the Inconel (registered trademark) include Inconel 600, Inconel 625, Inconel 690, Inconel 718, Inconel X750, etc. Specific examples of the Carpenter (registered trademark) include Carpenter 20Cb3, etc.

[0062] Specific examples of the Monel include Monel (Monel 400), Monel (Monel K500), Monel (Monel R), and Monel (Monel S).

[0063] When the conductive layer includes the inorganic layer, examples of the metal compound constituting the conductive layer include metal oxides such as tin-doped indium oxide (ITO), fluorine-doped tin oxide (FTO), antimony-doped tin oxide (ATO), aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), titanium oxide (TiO), etc. When the conductive layer has a layer composed of a metal compound, the layer composed of the metal compound may be a single layer or multiple layers.

[0064] When the conductive layer includes the inorganic layer, the conductive layer preferably has a layer composed of gold, silver, copper, platinum, titanium, tin, stainless steel (SUS), a molybdenum-containing alloy (such as Hastelloy), tin-doped indium oxide (ITO), fluorine-doped tin oxide (FTO), antimony-doped tin oxide (ATO), aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), or titanium oxide (TiO), from the viewpoints of making the conductive layer less susceptible to cracking and easily maintaining stable conductivity. Furthermore, the conductive layer more preferably has a layer composed of gold, silver, copper, platinum, titanium, tin, or stainless steel (SUS), from the viewpoints of further enhancing the heat resistance of the resulting adhesive tape for semiconductor processing, and even more preferably has a layer composed of stainless steel (SUS), from the viewpoints of suppressing surface reflection and improving visibility.

[0065] The preferred lower limit of the thickness of the entire conductive layer is 0.001 μm, and the preferred upper limit is 1 μm. By having the thickness of the entire conductive layer within this range, it becomes easier to adjust the transparency and surface resistivity of the resulting semiconductor processing adhesive tape to the desired range. Furthermore, if the thickness of the entire conductive layer is 0.001 μm or more, oxidation of the conductive layer when heated (mainly oxidation due to oxygen absorbed from the adhesive layer) is suppressed, and the charge-inhibiting performance of the resulting semiconductor processing adhesive tape can be maintained. From the viewpoint of further improving the charge-inhibiting performance and transparency of the semiconductor processing adhesive tape, the more preferred lower limit of the thickness of the entire conductive layer is 0.01 μm, the more preferred upper limit is 0.3 μm, the even more preferred lower limit is 0.02 μm, and the even more preferred upper limit is 0.1 μm.

[0066] The transparency and surface resistivity of the pressure-sensitive adhesive tape for semiconductor processing are adjusted by the type and thickness of the layers constituting the conductive layer, and therefore it is more preferable to select an optimal thickness for each type of layer constituting the conductive layer.

[0067] When the conductive layer has a layer composed of a conductive polymer, the preferred lower limit of the thickness of the layer composed of the conductive polymer is 0.005 μm, and the preferred upper limit is 1 μm. By having the thickness of the layer composed of the conductive polymer within the above range, it becomes easier to adjust the transparency and surface resistivity of the resulting semiconductor processing adhesive tape to the desired range. Furthermore, when the thickness of the layer composed of the conductive polymer is 0.005 μm or more, oxidation of the conductive layer when heated (mainly oxidation due to oxygen absorbed from the adhesive layer) is suppressed, and the charge-inhibiting performance of the resulting semiconductor processing adhesive tape can be maintained. From the viewpoint of further improving the charge-inhibiting performance and transparency of the semiconductor processing adhesive tape, the more preferred lower limit of the thickness of the layer composed of the conductive polymer is 0.01 μm, and the more preferred upper limit is 0.3 μm, and the even more preferred lower limit is 0.02 μm, and the even more preferred upper limit is 0.1 μm.

[0068] When the conductive layer has a layer composed of a metal, the preferred lower limit is 0.001 μm, and the preferred upper limit is 0.1 μm. When the thickness of the metal layer is within this range, it is easier to adjust the transparency and surface resistivity of the semiconductor processing adhesive tape to the desired range. Furthermore, when the thickness of the metal layer is 0.001 μm or more, oxidation of the conductive layer that occurs when heat is applied (mainly oxidation due to oxygen absorbed from the adhesive layer side) is suppressed, and the charge-inhibiting performance of the resulting semiconductor processing adhesive tape can be maintained. From the viewpoint of further improving the charge-inhibiting performance and transparency of the semiconductor processing adhesive tape, the more preferred lower limit of the thickness of the metal layer is 0.003 μm, the more preferred upper limit is 0.05 μm, and the even more preferred upper limit is 0.01 μm.

[0069] When the conductive layer has a layer composed of an alloy, the preferred lower limit of the thickness of the layer composed of the alloy is 0.001 μm, and the preferred upper limit is 0.1 μm. By having the thickness of the layer composed of the alloy within this range, it becomes easier to adjust the transparency and surface resistivity of the obtained adhesive tape for semiconductor processing to the desired range. Furthermore, if the thickness of the layer composed of the alloy is 0.001 μm or more, oxidation of the conductive layer that occurs when heat is applied (mainly oxidation due to oxygen absorbed from the adhesive layer side) is suppressed, and the electrostatic charge suppression performance of the obtained adhesive tape for semiconductor processing can be maintained. From the viewpoint of further improving the electrostatic charge suppression performance and transparency of the adhesive tape for semiconductor processing, the preferred upper limit of the thickness of the layer composed of the alloy is 0.03 μm, and even more preferably 0.01 μm.

[0070] When the conductive layer has a layer composed of a metal oxide, the preferred lower limit of the thickness of the metal oxide layer is 0.001 μm, and the preferred upper limit is 0.1 μm. When the thickness of the metal oxide layer is within this range, it becomes easier to adjust the transparency and surface resistivity of the resulting semiconductor processing adhesive tape to the desired range. Furthermore, when the thickness of the metal oxide layer is 0.001 μm or more, oxidation of the conductive layer (mainly due to oxygen absorbed from the adhesive layer) that occurs when heat is applied is suppressed, thereby maintaining the anti-static performance of the resulting semiconductor processing adhesive tape. From the viewpoint of further enhancing the anti-static performance and transparency of the semiconductor processing adhesive tape, the more preferred upper limit of the thickness of the metal oxide layer is 0.05 μm.

[0071] The conductive layer may be laminated over the entire surface of one side of the pressure-sensitive adhesive layer, or may be laminated partially on a portion of the surface. When the conductive layer is laminated over the entire surface of one side of the pressure-sensitive adhesive layer, the resulting pressure-sensitive adhesive tape for semiconductor processing can exhibit uniform anti-static performance. When the conductive layer is laminated partially on a portion of one side of the pressure-sensitive adhesive layer, the conductive layer preferably forms a uniform pattern shape in order to impart uniform anti-static performance. When the conductive layer forms a uniform pattern shape, the resulting pressure-sensitive adhesive tape for semiconductor processing can also exhibit high transparency while exhibiting uniform anti-static performance.

[0072] The method for forming the conductive layer is not particularly limited, and may be a conventionally known method such as a sputtering process such as DC sputtering, ion plating, a plasma CVD process, a vapor deposition process, a coating process, a dipping process, etc. Among these, the sputtering process is preferred because it can form a uniform conductive layer.

[0073] The adhesive tape for semiconductor processing of the present invention has a substrate. By having the substrate, the adhesive tape for semiconductor processing can be easily peeled off without the adhesive layer being torn off and leaving a residue when the adhesive tape for semiconductor processing is peeled off. In a preferred embodiment of the present disclosure, the substrate is preferably in the form of a film without holes, from the viewpoint of enabling stable transportation during the production of semiconductor devices.

[0074] The substrate is not particularly limited as long as it does not reduce the transparency and antistatic properties of the semiconductor processing adhesive tape, but it is preferable that the substrate contains a resin (A1) having a main chain structure including at least one repeating unit selected from the group consisting of an ether bond, a ketone group, and an ester bond. When the substrate contains the resin (A1), the heat resistance of the resulting semiconductor processing adhesive tape is further improved. Furthermore, from the viewpoint of further improving the transparency of the semiconductor processing adhesive tape, it is preferable that the substrate contains a polyester resin, a polyether resin, or the like. Such resin materials may be used alone or in combination of two or more.

[0075] Examples of the resin (A1) include polyether ether ketone (PEEK), polyethylene naphthalate (PEN), polyetherimide, polyamide, and polyimide.

[0076] The preferred lower limit of the thickness of the substrate is 5 μm, and the preferred upper limit is 125 μm. By having the thickness of the substrate within the above range, stable transportation can be achieved during the manufacture of semiconductor devices. The more preferred lower limit of the thickness of the substrate is 10 μm, and the more preferred upper limit is 75 μm, and the even more preferred lower limit is 15 μm, and the even more preferred upper limit is 50 μm.

[0077] The pressure-sensitive adhesive tape for semiconductor processing may have layers other than the pressure-sensitive adhesive layer, the conductive layer, and the substrate, as long as the effects of the present invention are not impaired.

[0078] The method for producing the semiconductor processing adhesive tape is not particularly limited, and it can be produced by a conventionally known method. Specifically, for example, a conductive layer is first formed on a substrate by the above-mentioned method (e.g., DC sputtering). A photocurable adhesive is obtained by mixing the polymerizable polymer with additives such as a photopolymerization initiator, if necessary. The photocurable adhesive is then applied to the release-treated surface of a release PET film and dried at 110°C for 5 minutes to produce a laminated film with an adhesive layer. The adhesive layer of the laminated film is then superimposed on the conductive layer, and the laminated film can be produced by laminating and integrating the adhesive layer.

[0079] The adhesive tape for semiconductor processing is laminated to a silicon wafer, and then irradiated with light having a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm. ２ When irradiated with UV light, the 180° peel strength at 23°C and a peeling rate of 300 mm / min (hereinafter sometimes simply referred to as "the 180° peel strength of the adhesive tape for semiconductor processing from a silicon wafer before heating") is less than 0.15 N / 25 mm. Since the 180° peel strength of the adhesive tape for semiconductor processing from a silicon wafer before heating is less than 0.15 N / 25 mm, the adhesive tape can be easily peeled without leaving any residue even after heating. The preferred upper limit of the 180° peel strength of the adhesive tape for semiconductor processing from a silicon wafer before heating is 0.10 N / 25 mm, and the more preferred upper limit is 0.05 N / 25 mm. Furthermore, from the viewpoint of preventing peeling of the adhesive tape for semiconductor processing during transportation in the manufacture of semiconductor devices, the preferred lower limit of the 180° peel strength of the adhesive tape for semiconductor processing from a silicon wafer before heating is 0.01 N / 25 mm.

[0080] The 180° peel strength of the semiconductor processing adhesive tape against a silicon wafer before heating can be measured by the following method. Specifically, the semiconductor processing adhesive tape is cut into a size of 25 mm wide x 100 mm long, and a 2 kg rubber roller is used to roll the tape back and forth at a speed of 600 mm / min to bond the semiconductor processing adhesive tape to the mirror surface of the silicon wafer. The tape is then left to stand for 20 minutes in an environment of 23°C and 50% RH to produce a laminate. Furthermore, a high-pressure mercury lamp is used to irradiate the semiconductor processing adhesive tape of the produced laminate with light of 405 nm wavelength at an integrated illuminance of 3000 mJ / cm. ２ from the substrate side (for example, wavelength 405 nm, illuminance 100 mW / cm ２ A peel test is performed on the obtained measurement sample in accordance with JIS Z0237 using a tensile tester (Shimadzu Corporation, "AGS-X" or the like) at 23°C, a peel rate of 300 mm / min, and a peel angle of 180°, and the semiconductor processing adhesive tape is peeled off from the silicon wafer at 180°, whereby measurement can be performed.

[0081] The adhesive tape for semiconductor processing is laminated to a silicon wafer, and then irradiated with light having a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm. ２After irradiation with UV light, the semiconductor processing adhesive tape is further heated at 260°C for 5 minutes and then at 180°C for 3 hours, and then the 180° peel force of the semiconductor processing adhesive tape at 23°C and a peel rate of 300 mm / min (hereinafter sometimes simply referred to as "the 180° peel force of the semiconductor processing adhesive tape from a silicon wafer after heating") is 0.5 N / 25 mm or less. Since the 180° peel force of the semiconductor processing adhesive tape from a silicon wafer after heating is 0.5 N / 25 mm or less, the wafer can be easily peeled off without damaging it even after high-temperature treatment. The 180° peel force of the semiconductor processing adhesive tape from a silicon wafer after heating is preferably less than 0.5 N / 25 mm, more preferably 0.3 N / 25 mm or less, and even more preferably 0.2 N / 25 mm or less. From the viewpoint of not contaminating the wafer surface after peeling, the preferred lower limit of the 180° peel strength of the adhesive tape for semiconductor processing from a silicon wafer after heating is 0.01 N / 25 mm.

[0082] The 180° peel strength of the adhesive tape for semiconductor processing from a silicon wafer after heating can be measured by further heating a test sample prepared in the above-mentioned method for measuring the 180° peel strength of the adhesive tape for semiconductor processing from a silicon wafer before heating in an oven at 260°C for 5 minutes, air-cooling it once, and then heating it at 180°C for 3 hours and air-cooling it, and then performing a 180° peel test under the same conditions using the air-cooled test sample.

[0083] Methods for adjusting the 180° peel strength from a silicon wafer of the semiconductor processing adhesive tape before heating and the 180° peel strength from a silicon wafer after heating within the above-mentioned ranges include, for example, changing the composition of the adhesive layer, changing the thickness of the adhesive layer, and changing the degree of crosslinking of the adhesive layer. Specific examples of methods for changing the composition of the adhesive layer include incorporating the curing agent, photopolymerization initiator, and release agent into the photocurable adhesive and adjusting the type and content thereof. Specific examples of methods for adjusting the degree of crosslinking of the adhesive layer include incorporating the curing agent and photopolymerization initiator into the photocurable adhesive and adjusting the type and content thereof.

[0084] The adhesive tape for semiconductor processing has a visible light transmittance measured from the conductive layer side (hereinafter sometimes simply referred to as "visible light transmittance of the adhesive tape for semiconductor processing") of 50%. When the adhesive tape for semiconductor processing has a visible light transmittance of 50% or more, when the adhesive tape for semiconductor processing is used to protect a semiconductor device, the circuit pattern of the semiconductor device can be recognized from the adhesive tape side, allowing for positioning during processing, etc. The preferred lower limit of the visible light transmittance of the adhesive tape for semiconductor processing is 60%, and more preferably 70%. The upper limit of the visible light transmittance of the adhesive tape for semiconductor processing is not particularly limited, and may be 100%.

[0085] The visible light transmittance of the pressure-sensitive adhesive tape for semiconductor processing can be measured using a haze meter (for example, "HM-150" manufactured by Murakami Color Research Laboratory Co., Ltd.) in accordance with JIS K 7136. In this specification, the wavelength region of visible light for measuring the visible light transmittance is 300 nm to 830 nm.

[0086] The visible light transmittance of the semiconductor processing adhesive tape, measured from the conductive layer side, can be adjusted by changing the composition of the photocurable adhesive, changing the type or thickness of the conductive layer, or changing the type or thickness of the substrate. Examples of methods for changing the composition of the photocurable adhesive include adjusting the type and content of the filler. Specifically, the visible light transmittance of the semiconductor processing adhesive tape can be increased by using a filler with a small average particle size or by reducing the filler content. Examples of methods for changing the type of the conductive layer include, for example, making the conductive layer an organic layer, making the conductive layer contain a conductive polymer, adjusting the content of the conductive polymer (if carbon black) contained in the conductive layer, and changing the type of metal constituting the inorganic layer. Examples of methods for changing the type of substrate include, for example, using a substrate containing a polyester resin, which can increase the visible light transmittance of the semiconductor processing adhesive tape. Furthermore, the visible light transmittance of the pressure-sensitive adhesive tape for semiconductor processing can also be increased by reducing the thickness of the substrate.

[0087] The adhesive tape for semiconductor processing is irradiated with light having a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm ２ The surface resistivity of the adhesive layer side of the adhesive tape for semiconductor processing after irradiation with light (hereinafter, sometimes simply referred to as "surface resistivity of the adhesive tape for semiconductor processing before heating") is R １ Ω / □, and the semiconductor processing adhesive tape was irradiated with light of wavelength 405 nm at an integrated illuminance of 3000 mJ / cm ２ After irradiation with 1000 kJ / cm 3 at 260°C, the adhesive tape was further heated at 260°C for 5 minutes and then heated at 180°C for 3 hours. The surface resistivity of the adhesive layer side of the adhesive tape for semiconductor processing (hereinafter, sometimes simply referred to as "surface resistivity of the adhesive tape for semiconductor processing after heating") was R ２ When Ω / □ is used, the above R １ and the above R ２ are both 1.0 x 10 １４It is preferable that the R １ and the above R ２ Both are 1.0 x 10 １４ When the R is Ω / □ or less, the pressure-sensitive adhesive tape for semiconductor processing has excellent anti-static properties at both room temperature and high temperature. １ and the above R ２ A more preferable upper limit is 1.0 × 10 １３ Ω / □, and a more preferable upper limit is 1.0×10 １２ Ω / □. １ and the above R ２ The preferred lower limit is 1.0 × 10 ３ Ω / □. １ and the above R ２ Both are 1.0 x 10 ３ By having a resistivity of Ω / □ or more, when the adhesive tape for semiconductor processing is used to protect a semiconductor device, short circuits can be further suppressed. １ and the above R ２ A more preferable lower limit is 1.0 × 10 ４ Ω / □, and a more preferable lower limit is 1.0×10 ５ Ω / □, and an even more preferable lower limit is 1.0×10 ８ Ω / □, and a particularly preferred lower limit is 1.0×10 １０ It is Ω / □.

[0088] The surface resistivity of the pressure-sensitive adhesive tape for semiconductor processing before heating and the surface resistivity of the pressure-sensitive adhesive tape for semiconductor processing after heating can be measured by a method in accordance with JIS K7194.

[0089] The pressure-sensitive adhesive tape for semiconductor processing has a rate of change R in surface resistivity of the pressure-sensitive adhesive layer side of the pressure-sensitive adhesive tape for semiconductor processing before and after heating. ２ / R １ (hereinafter, it may be simply referred to as "the rate of change in surface resistivity of the adhesive tape for semiconductor processing before and after heating") is preferably 500 or less. ２ / R １ When R is within the above range, it becomes possible to exhibit more stable charge suppression performance even when the method for producing a semiconductor includes a heat treatment step.２ / R １ is more preferably less than 500, and ２ / R １ is more preferably 150 or less, and the above R ２ / R １ is even more preferably 100 or less, and the above R ２ / R １ is particularly preferably 10 or less. ２ / R １ From the viewpoint of the stability of the charge suppression performance, the lower limit of is preferably 1.0, more preferably 2.0, and even more preferably 4.0.

[0090] The preferred upper limit of the surface resistivity of the pressure-sensitive adhesive layer side of the pressure-sensitive adhesive tape for semiconductor processing (hereinafter, also referred to as "surface resistivity of the pressure-sensitive adhesive tape for semiconductor processing before light irradiation") is 5.0 × 10 １３ The surface resistivity of the adhesive tape for semiconductor processing before light irradiation is 5.0×10 １３ By setting the surface resistivity at Ω / □ or less, the resulting adhesive tape for semiconductor processing has excellent anti-static properties even after light irradiation or high-temperature treatment. A more preferable upper limit of the surface resistivity of the adhesive tape for semiconductor processing before light irradiation is 1.0 × 10 １３ Ω / □, and a more preferable upper limit is 5.0×10 １２ In addition, the surface resistivity of the pressure-sensitive adhesive tape for semiconductor processing before light irradiation is preferably 1.0 × 10 Ω / □ from the viewpoint of the stability of the charge suppression performance after the high-temperature treatment process. ４ Ω / □, and a more preferable lower limit is 1.0×10 ５ Ω / □, and an even more preferable lower limit is 1.0×10 ８ Ω / □, and a particularly preferred lower limit is 1.0×10 ９ It is Ω / □.

[0091] The surface resistivity of the pressure-sensitive adhesive tape for semiconductor processing before light irradiation can be measured by a method in accordance with JIS K7194.

[0092] The surface resistivity of the semiconductor processing adhesive tape before heating, the surface resistivity of the semiconductor processing adhesive tape after heating, and the surface resistivity of the semiconductor processing adhesive tape before light irradiation can be controlled by adjusting the amount of oxidation of the conductive layer, adjusting the thickness of the conductive layer, or by changing the type of conductive layer to one that contains a conductive polymer.

[0093] The semiconductor processing adhesive tape preferably has an upper limit of 10% for the thermal weight loss rate at 260°C. Since the semiconductor processing adhesive tape has a thermal weight loss rate of 10% or less at 260°C, the semiconductor processing adhesive tape can be more suitably used in semiconductor manufacturing processes that include high-temperature treatment. The semiconductor processing adhesive tape's upper limit for the thermal weight loss rate at 260°C is more preferably 8%, and even more preferably 5%. There is no particular restriction on the lower limit for the thermal weight loss rate at 260°C of the semiconductor processing adhesive tape, with 0% being the most preferred.

[0094] The thermal weight loss rate of the above-mentioned adhesive tape for semiconductor processing at 260°C can be determined by weighing 5 to 10 mg of tape in the aluminum pan of a thermobalance (for example, "TG / DTA6200" manufactured by SII Corporation) and heating the tape from room temperature (30°C) to 400°C in an air atmosphere (flow rate 200 mL / min) at a heating rate of 5°C / min, and then measuring the weight loss rate at 260°C.

[0095] The thermal weight loss rate of the above-mentioned adhesive tape for semiconductor processing at 260°C can be controlled by adjusting the weight average molecular weight of the polymerizable polymer contained in the photocurable adhesive, changing the synthesis method of the polymerizable polymer to a polymerization method that leaves less monomer components, or changing the type of substrate to one with high heat resistance.

[0096] The semiconductor processing adhesive tape is preferably used in semiconductor manufacturing processes to protect circuits by being applied to the circuit surface of a semiconductor device. The semiconductor processing adhesive tape can prevent damage to the circuit due to static electricity. Because the semiconductor processing adhesive tape has excellent transparency, when applied to the circuit surface of a semiconductor device in the semiconductor manufacturing process, the circuit pattern on the semiconductor device can be easily recognized through the tape, facilitating process management in the semiconductor manufacturing process. Furthermore, the semiconductor processing adhesive tape exhibits excellent anti-static properties, even when subjected to high-temperature treatment, thereby preventing cracking of the semiconductor device when the tape is peeled off. Therefore, the semiconductor processing adhesive tape is particularly suitable for use in semiconductor manufacturing processes using thin-film wafers, which are prone to breakage. Furthermore, the semiconductor processing adhesive tape can be easily peeled off from the adherend while suppressing adhesive residue even after high-temperature treatment, making it suitable for protecting and temporarily fixing adherends in semiconductor manufacturing processes that involve high-temperature treatment. It is particularly suitable for use in semiconductor manufacturing processes involving reflow processes and mold resin curing processes.

[0097] The present disclosure also provides a method for manufacturing a semiconductor, including the steps of attaching the adhesive tape for semiconductor processing to a semiconductor device to produce a laminate (hereinafter sometimes simply referred to as "step (i)"), heating the laminate (hereinafter sometimes simply referred to as "step (ii)"), and peeling the adhesive tape for semiconductor processing from the laminate (hereinafter sometimes simply referred to as "step (iii)"). The method for manufacturing a semiconductor facilitates process control in the semiconductor manufacturing process, and can suppress cracking of the semiconductor device and adhesive residue on the semiconductor device when the adhesive tape for semiconductor processing is peeled off, thereby improving the quality and yield of the semiconductor devices manufactured.

[0098] In the step (i), the method for attaching the adhesive tape for semiconductor processing to the semiconductor device is not particularly limited, and examples thereof include lamination using a laminator under atmospheric pressure, vacuum lamination using a vacuum laminator under vacuum, etc. Among these, vacuum lamination using a vacuum laminator is preferred from the viewpoint of in-plane uniformity and suppressing the generation of voids due to problems during attachment.

[0099] The step (ii) is not particularly limited as long as it is a step of heating the laminate (high-temperature treatment), and examples thereof include a reflow process, a mold resin curing process, and a CVD process.

[0100] In the step (iii), methods for peeling the adhesive tape for semiconductor processing from the laminate include, for example, a method of peeling using a dicing tape (dicing pick-up), a method of peeling the adhesive tape for semiconductor processing directly by hand or with a tape roll (peel peeling), and the like.

[0101] The semiconductor manufacturing method may include other steps in addition to the steps (i) to (iii) as long as the effects of the present invention are not impaired. For example, the other steps may include, after the step (i), irradiating the laminate with light or ultraviolet light from the semiconductor processing adhesive tape side to harden the adhesive layer of the semiconductor processing adhesive tape. Hardening the adhesive layer of the semiconductor processing adhesive tape can suppress peeling due to swelling of the adhesive during chemical cleaning and increased adhesion to the adherend surface during heating processes.

[0102] The type of semiconductor that is preferably manufactured using the above semiconductor manufacturing method is not particularly limited, but it can be suitably used for manufacturing semiconductors in which semiconductor devices are densely integrated, and in particular, it can be suitably used for manufacturing TSVs.

[0103] According to the present invention, it is possible to provide an adhesive tape for semiconductor processing that has excellent anti-static properties and transparency and can be easily peeled even after high-temperature treatment. Furthermore, according to the present invention, it is possible to provide a method for manufacturing a semiconductor using the adhesive tape for semiconductor processing.

[0104] The following examples will explain the present invention in more detail, but the present invention is not limited to these examples.

[0105] (Example 1) (1) Formation of Conductive Layer A conductive layer having a thickness of 0.05 μm was formed on a polyethylene naphthalate (PEN) substrate (Teonex, manufactured by Toyobo Co., Ltd.) by gravure coating an aqueous dispersion of a PEDOT / PSS mixture (Denatron, manufactured by Nagase ChemteX Corporation).

[0106] (2) Preparation of Photocurable Pressure Sensitive Adhesive: A reactor equipped with a thermometer, a stirrer, and a cooling tube was prepared. 90 parts by mass of 2-ethylhexyl acrylate as a (meth)acrylic acid alkyl ester, 10 parts by mass of hydroxyethyl methacrylate as a functional group-containing monomer, 0.01 parts by mass of lauryl mercaptan, and 80 parts by mass of ethyl acetate were added to the reactor, and the reactor was heated to initiate reflux. Subsequently, 0.01 parts by mass of 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane as a polymerization initiator was added to the reactor, and polymerization was initiated under reflux. Next, 0.01 parts by mass of 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane was added at 1 hour and 2 hours after the start of polymerization, and then 0.05 parts by mass of t-hexylperoxypivalate was added 4 hours after the start of polymerization to continue the polymerization reaction. Then, 8 hours after the start of 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 mass of 2-isocyanatoethyl methacrylate as a functional group-containing unsaturated compound was added to 100 parts by mass of the resin solid content of the obtained ethyl acetate solution containing the functional group-containing (meth)acrylic polymer, and the mixture was reacted to obtain a polymerizable polymer. Thereafter, 100 parts by mass of the resin solids content of the obtained ethyl acetate solution of the polymerizable polymer were mixed with 1 part by mass of a photopolymerization initiator (Esacure One, manufactured by Nippon SiberHegner AG) and 0.2 parts by mass of an isocyanate curing agent (Coronate L, manufactured by Tosoh Corporation), and then 10 parts by mass of a silicone release agent (EBECRYL350, manufactured by Daicel Allnex Co., Ltd.), 10 parts by mass of a urethane acrylate (UN-5500, manufactured by Negami Chemical Industrial Co., Ltd.), and 3 parts by mass of an inorganic filler (Reolosil MT-10, manufactured by Tokuyama Corporation), to obtain an ethyl acetate solution of a photocurable pressure-sensitive adhesive.

[0107] (3) Production of adhesive tape for semiconductor processing The obtained ethyl acetate solution of the photocurable adhesive was applied with a doctor knife to a 50 μm polyethylene terephthalate (PET) film with one side subjected to a release treatment, and the coating solution was dried by heating at 110 ° C for 5 minutes to form an adhesive layer with a thickness of 40 μm, thereby producing a laminated film. The adhesive layer of the obtained laminated film and the conductive layer formed in the above-mentioned "(1) Formation of conductive layer" were superimposed and laminated together, and then cured in an environment of 40 ° C for 5 days to obtain an adhesive tape for semiconductor processing having an adhesive layer, a conductive layer, and a substrate in this order.

[0108] (4) Measurement of 180° peel strength of adhesive tape for semiconductor processing against silicon wafer before heating The obtained adhesive tape for semiconductor processing was cut into a size of 25 mm wide x 100 mm long, and the adhesive tape for semiconductor processing was laminated to the mirror surface of the silicon wafer by rolling it back and forth once at a speed of 600 mm / min using a 2 kg rubber roller, and then left to stand for 20 minutes in an environment of 23°C and 50% RH to prepare a laminate. A high-pressure mercury lamp was used to irradiate the adhesive tape for semiconductor processing of the prepared laminate from the substrate side with light of 405 nm wavelength at an integrated illuminance of 3000 mJ / cm. ２ (wavelength 405 nm, illuminance 100 mW / cm ２ A measurement sample was prepared by irradiating the sample with light of 1000 nm for 30 seconds. A peel test was performed on the obtained measurement sample in accordance with JIS Z0237 using a tensile tester (Shimadzu Corporation, "AGS-X") at 23°C, a peel rate of 300 mm / min, and a peel angle of 180°. The adhesive tape for semiconductor processing was peeled off from the silicon wafer at 180° to measure the 180° peel strength (N / 25 mm). The results are shown in Table 1.

[0109] (5) Measurement of 180° peel strength from silicon wafer after heating of adhesive tape for semiconductor processing The test sample prepared in the above-mentioned "(4) Measurement of 180° peel strength from silicon wafer before heating of adhesive tape for semiconductor processing" was further heated in an oven at 260°C for 5 minutes, air-cooled once, and then heated at 180°C for 3 hours. After air-cooling the heated test sample, a 180° peel test was performed under the same conditions as in the above-mentioned "(4) Measurement of 180° peel strength from silicon wafer before heating of adhesive tape for semiconductor processing" to measure the 180° peel strength (N / 25 mm). The results are shown in Table 1.

[0110] (6) Measurement of Visible Light Transmittance of Adhesive Layer Side of Semiconductor Processing Adhesive Tape The visible light transmittance (%) of the adhesive layer side of the semiconductor processing adhesive tape was measured using a haze meter ("HM-150" manufactured by Murakami Color Research Laboratory Co., Ltd.) in accordance with JIS K 7136. The results are shown in Table 1.

[0111] (7) Measurement of surface resistivity of adhesive layer side of adhesive tape for semiconductor processing The obtained adhesive tape for semiconductor processing was used as a test piece, and the obtained adhesive tape for semiconductor processing was irradiated with light of a wavelength of 405 nm using a high-pressure mercury lamp from the substrate side of the adhesive tape for semiconductor processing at an integrated illuminance of 3000 mJ / cm ２ (Wavelength 405nm, illuminance 100mW / cm ２ Test pieces irradiated with 1000 W of light for 30 seconds) and semiconductor processing adhesive tapes irradiated with light under the same conditions were further heated in an oven at 260°C for 5 minutes, air-cooled once, and then heated at 180°C for 3 hours and air-cooled to prepare test pieces. For each of the obtained test pieces, the surface resistivity of the adhesive layer of the obtained adhesive tape was measured at nine points using a probe (manufactured by Nitto Seiko Co., Ltd., "Hiresta-UX MCP-HT800") with probe needles spaced at equal intervals in a straight line, using a method in accordance with JIS K7194. The average value was calculated as the surface resistivity, and the surface resistivity (Ω / □) of the adhesive layer side of the semiconductor processing adhesive tape was measured. The results are shown in Table 1.

[0112] (8) Measurement of thermal weight loss rate of adhesive tape for semiconductor processing at 260°C 5 to 10 mg of adhesive tape was weighed into the aluminum pan of a thermobalance (TG / DTA6200, manufactured by SII Corporation), and the temperature was raised from room temperature (30°C) to 400°C in an air atmosphere (flow rate 200 mL / min) at a temperature rise rate of 5°C / min. The thermal weight loss rate (%) at 260°C was then determined. The results are shown in Table 1.

[0113] Examples 2 to 6, 8 to 12: Semiconductor processing adhesive tapes were manufactured and measured in the same manner as in Example 1, except that the content of the silicone-based release agent (EBECRYL 350, manufactured by Daicel Allnex Corporation) in the photocurable adhesive, the thickness of the adhesive layer, the type and thickness of the conductive layer, and the type and thickness of the substrate were as shown in Table 1. The results are shown in Table 1. For the conductive layer in Example 6, a conductive layer was formed on a polyethylene naphthalate (PEN)-containing substrate by DC magnetron sputtering using a sputtering apparatus (exhaust capacity: 2600 sccm / Pa) and an SUS304 plate as a target material. In this specification, "sccm / Pa" refers to the flow rate required for evacuation when reducing the vacuum level to 1 Pa.

[0114] (Example 7) Carbon nanotubes (manufactured by JEIO Corporation, "JENOTUBE 8A") were gravure coated onto a polyethylene naphthalate (PEN)-containing substrate to form a conductive layer composed of carbon nanotubes on the substrate. Furthermore, an adhesive tape for semiconductor processing was produced and measured in the same manner as in Example 1, except that the thickness of the adhesive layer, the type and thickness of the conductive layer, and the type and thickness of the substrate were as shown in Table 1. The results are shown in Table 1.

[0115] Comparative Example 1 An adhesive tape for semiconductor processing was produced and measured in the same manner as in Example 1, except that the adhesive layer of the laminated film obtained in the above-mentioned "(3) Production of adhesive tape for semiconductor processing" was attached to the surface of the substrate not coated with the conductive layer in the above-mentioned "(1) Formation of conductive layer" to produce an adhesive tape for semiconductor processing having a conductive layer, substrate, and adhesive layer in this order. The results are shown in Table 2.

[0116] Comparative Example 2 An adhesive tape for semiconductor processing was produced and measured in the same manner as in Example 1, except that in the above-mentioned "(3) Production of an adhesive tape for semiconductor processing," a substrate was attached to the adhesive layer of the obtained laminated film and cured for 5 days in an environment of 40° C. The results are shown in Table 2.

[0117] Comparative Example 3 An adhesive tape for semiconductor processing was produced and measured in the same manner as in Example 1, except that in the above-mentioned "(2) Preparation of photocurable adhesive," 10 parts by mass of a conductive polymer (PEDOT / PSS) was mixed and no conductive layer was used. The results are shown in Table 2.

[0118] Comparative Example 4 An adhesive tape for semiconductor processing was produced and measured in the same manner as in Example 1, except that in the above-mentioned "(2) Preparation of photocurable adhesive," the silicone-based release agent was used in an amount of 1 part by mass. The results are shown in Table 2.

[0119] Comparative Example 5 An adhesive tape for semiconductor processing was produced and measured in the same manner as in Example 1, except that in the above-mentioned "(2) Preparation of photocurable adhesive," the amount of the silicone-based release agent was set to 0 parts by mass. The results are shown in Table 2.

[0120] (Comparative Example 6) A conductive layer having a metal film was produced by DC magnetron sputtering using a sputtering device (exhaust capacity: 2600 sccm / Pa) with SUS as a target material on a polyethylene naphthalate (PEN)-containing substrate. A semiconductor processing adhesive tape was produced and measured in the same manner as in Example 1, except for the above. The results are shown in Table 2. The surface resistivity of the adhesive layer side of the semiconductor processing adhesive tape and the thermal weight loss rate of the semiconductor processing adhesive tape at 260°C were not evaluated because the "transparency" evaluation, which will be described later, was poor.

[0121] <Evaluation> The adhesive tapes for semiconductor processing obtained in the Examples and Comparative Examples were evaluated by the following methods. The results are shown in Tables 1 and 2.

[0122] (Transparency) The obtained adhesive tape was attached to the circuit surface of a semiconductor device with an alignment mark on the circuit surface. A "+" mark measuring 100 μm in length and 100 μm in width was used as the alignment mark. In this state, the circuit surface of the semiconductor device was observed with a camera from the semiconductor processing adhesive tape side. This operation was performed 10 times. The evaluation was given as "◎" if the alignment mark was recognized by the camera 10 times out of 10 times, "○" if the alignment mark was recognized by the camera 5 to 9 times, and "×" if the alignment mark was recognized by the camera only 4 times or less. The observation was performed using the alignment mark recognition function of a dicing machine (DISCO Corporation, "DFD6361"). The recognition of the alignment mark was confirmed under conditions of epi-illumination output of 20 to 80% and oblique illumination output of 20 to 80%.

[0123] (Removability after High-Temperature Treatment) (1) Residue on Wafer Surface After Peeling of Adhesive Tape A bump wafer was produced on the mirror surface of a 725 μm-thick silicon mirror wafer using a dicing machine (DISCO Corporation, "DFD6360"), with a circuit having a step height of approximately 10 μm. Using a vacuum laminator (Takatori Corporation, "ATM-812M"), the obtained adhesive tape for semiconductor processing was bonded to the mirror surface of the produced bump wafer under the conditions of a lamination speed of 30 mm / sec, a lamination temperature of 23°C, a lamination pressure of 0 MPa, a degree of vacuum of 100 Pa, and one-way lamination, to produce a laminate. The produced laminate was then left to stand in an environment of 23°C and 50% RH for approximately 20 minutes, and then irradiated with light of 405 nm wavelength at an integrated illuminance of 3000 mJ / cm using an ultra-high-pressure mercury lamp. ２ (Wavelength 405nm, illuminance 100mW / cm ２The laminate was irradiated with light from the substrate side of the semiconductor processing adhesive tape for 30 seconds. The laminate after light irradiation was heated at 260°C for 5 minutes using an oven (ETAC Corporation, "CSO603"), air-cooled once, and then heated at 180°C for 3 hours and air-cooled to prepare a measurement sample. The prepared measurement sample was peeled from the laminate using a tensile tester (Shimadzu Corporation, "AGS-X") in accordance with JIS Z0237 under conditions of 23°C, a peel rate of 300 mm / min, and a peel angle of 180°. Five 0.1 mm x 0.1 mm images were prepared using an optical microscope (Keyence Corporation, "VHX-970F", 10x magnification) of the bump wafer surface from which the semiconductor processing adhesive tape had been peeled, and the residue (adhesive residue) on the wafer after the adhesive tape was peeled was observed. The peelability of the adhesive tape for semiconductor processing after high-temperature treatment was evaluated as follows: "A" if no adhesive residue was found in the image; "○" if adhesive residue was found in the image but accounted for less than 5% of the total area of ​​the five images; and "×" if adhesive residue was found in the image but accounted for 5% or more of the total area of ​​the five images. Note that for Comparative Example 6, the above-mentioned "transparency" rating was "×," so no evaluation was performed.

[0124] (2) Wafer cracking The obtained pressure-sensitive adhesive tape was bonded to a silicon wafer having a thickness of 50 μm using a vacuum laminator (manufactured by Takatori Corporation, "ATM-812M") under the conditions of a laminating speed of 30 mm / sec, a laminating temperature of 23°C, a laminating pressure of 0 MPa, a degree of vacuum of 100 Pa, and one-way lamination, to prepare a laminate. The prepared laminate was then left to stand for 20 minutes in an environment of 23°C and 50% RH, and then irradiated with light of a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm using an ultra-high pressure mercury lamp. ２ (Wavelength 405nm, illuminance 100mW / cm ２The laminate was irradiated with light from the semiconductor processing adhesive tape side for 30 seconds. After light irradiation, the laminate was heated to 260 ° C for 5 minutes using an oven (ETAC Corporation, "CSO603"), air-cooled once, and then heated at 180 ° C for 3 hours and air-cooled to prepare a total of 10 measurement samples. For each of the prepared measurement samples, a tensile tester (Shimadzu Corporation, "AGS-X") was used in accordance with JIS Z0237 at 23 ° C, a peel rate of 300 mm / min, and a peel angle of 180 ° to peel the semiconductor processing adhesive tape from the laminate. The surface of the wafer after peeling the semiconductor processing adhesive tape was visually observed, and the peelability of the semiconductor processing adhesive tape after high-temperature treatment was evaluated by assigning "◎" to samples in which the wafer was not cracked, "○" to samples in which the wafer was cracked, and "×" to samples in which the wafer was cracked two or more. In addition, for Comparative Example 6, the evaluation of the above-mentioned "transparency" was x, so no evaluation was performed.

[0125] The types of conductive layers and substrates shown in Tables 1 and 2 are as follows: PEDOT / PSS: "Denatron" manufactured by Nagase ChemteX Corporation SUS: SUS304 CNT: carbon nanotubes ("JENOTUBE8A" manufactured by JEIO Corporation) PEN-containing substrate: polyethylene naphthalate-containing substrate ("Teonex" manufactured by Toyobo Co., Ltd.) PEEK-containing substrate: polyether ether ketone-containing substrate ("EXPEEK" manufactured by Kurabo Industries Ltd.)

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[0128] According to the present invention, it is possible to provide an adhesive tape for semiconductor processing that has excellent anti-static properties and transparency and can be easily peeled even after high-temperature treatment. Furthermore, according to the present invention, it is possible to provide a method for manufacturing a semiconductor using the adhesive tape for semiconductor processing.

Claims

1. A semiconductor processing adhesive tape comprising an adhesive layer, a conductive layer, and a substrate in this order, the adhesive layer containing a photocurable adhesive, the adhesive layer having a visible light transmittance of 50% or more as measured from the adhesive layer side, and after the semiconductor processing adhesive tape is bonded to a silicon wafer, the semiconductor processing adhesive tape is irradiated with light of a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm. ２ When the adhesive tape for semiconductor processing is irradiated with light having a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm, the 180° peel strength of the adhesive tape for semiconductor processing is less than 0.15 N / 25 mm at 23°C and a peeling speed of 300 mm / min, and after the adhesive tape for semiconductor processing is bonded to a silicon wafer, the adhesive tape for semiconductor processing is irradiated with light having a wavelength of 405 nm at an integrated illuminance of 3000 mJ / cm ２ and then further heating the adhesive tape at 260°C for 5 minutes and then at 180°C for 3 hours, the 180° peel strength of the adhesive tape for semiconductor processing at 23°C and a peel rate of 300 mm / min being 0.5 N / 25 mm or less.

2. Irradiate the adhesive tape for semiconductor processing with light of 405 nm wavelength at an integrated illuminance of 3000 mJ / cm ２ After irradiation with light, the surface resistivity of the adhesive layer side of the adhesive tape for semiconductor processing is R １ Ω / □, and the semiconductor processing adhesive tape was irradiated with light of wavelength 405 nm at an integrated illuminance of 3000 mJ / cm ２ After irradiation with 1000 kJ / cm2, the adhesive tape was further heated at 260° C. for 5 minutes, and then heated at 180° C. for 3 hours. The surface resistivity of the adhesive layer side of the adhesive tape for semiconductor processing was then measured. ２ When Ω / □ is used, the R １ and the above R ２ Both are 1.0 x 10 １４ Ω / □ or less, and the rate of change R in the surface resistivity of the pressure-sensitive adhesive layer side of the pressure-sensitive adhesive tape for semiconductor processing before and after heating ２ / R １ The adhesive tape for semiconductor processing according to claim 1, wherein the viscosity is 500 or less.

3. The adhesive tape for semiconductor processing according to claim 1 or 2, wherein the photocurable adhesive contains a filler.

4. The adhesive tape for semiconductor processing according to claim 1, 2 or 3, wherein the photocurable adhesive contains a release agent.

5. The adhesive tape for semiconductor processing according to claim 1, 2, 3 or 4, wherein the thickness of said adhesive layer is 10 μm or more and 300 μm or less.

6. The adhesive tape for semiconductor processing according to claim 1, 2, 3, 4 or 5, wherein the conductive layer includes an organic layer.

7. The adhesive tape for semiconductor processing according to claim 1, 2, 3, 4, 5 or 6, wherein the conductive layer contains a conductive polymer.

8. The adhesive tape for semiconductor processing according to claim 7, wherein the conductive polymer includes a polythiophene-based polymer.

9. The adhesive tape for semiconductor processing according to claim 1, 2, 3, 4, 5, 6, 7 or 8, wherein the thickness of the entire conductive layer is 0.001 μm or more and 1 μm or less.

10. An adhesive tape for semiconductor processing according to claim 1, 2, 3, 4, 5, 6, 7, 8 or 9, wherein the substrate contains a resin (A1) having in its main chain skeleton a repeating unit containing at least one selected from the group consisting of an ether bond, a ketone group, and an ester bond.

11. The adhesive tape for semiconductor processing according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, wherein the thermal weight loss rate of said adhesive tape for semiconductor processing at 260°C is 10% or less.

12. A method for manufacturing a semiconductor, comprising the steps of: attaching the adhesive tape for semiconductor processing according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11 to a semiconductor device to produce a laminate; heating the laminate; and peeling the adhesive tape for semiconductor processing from the laminate.

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