JP5631081B2 - Active energy ray curable adhesive for re-peeling - Google Patents

Description

  The present invention is, for example, an active energy ray-curable re-peeling adhesive used for surface protection and damage prevention when manufacturing processed parts such as semiconductors, circuits, various printed boards, various masks, and lead frames. About. In particular, the present invention relates to an active energy ray-curable pressure-sensitive adhesive for re-peeling that is preferably used as a pressure-sensitive adhesive sheet for processing a semiconductor wafer used during back grinding or dicing of a semiconductor wafer.

  A semiconductor wafer made of silicon, gallium, arsenic, or the like is manufactured in a large diameter state, and then the back surface is ground, further cut into pieces (dicing), and further transferred to a mounting process.

  In the process of grinding the back surface of the semiconductor wafer (back surface grinding process), an adhesive sheet obtained by applying an adhesive on a base material made of a plastic film is used to protect the pattern surface of the semiconductor wafer.

  Further, dicing, cleaning, expanding, picking up, and mounting are added in the element miniaturization and mounting process. In a process from a dicing process of a semiconductor wafer to a pick-up process, an adhesive sheet in which an adhesive is applied on a base material made of a plastic film is used.

  In the back grinding process, in order to protect the pattern surface of the semiconductor wafer, the adhesive sheet is required to be sufficiently adhered to the semiconductor wafer without being peeled off. Moreover, after grinding, it is required that it can be easily peeled off from the semiconductor wafer.

  In the dicing process, it is required that the cut and separated element pieces are not peeled off from the adhesive sheet. That is, the adhesive sheet is required to have high adhesiveness. On the other hand, in the pickup process, the cut and separated element pieces must be easily peeled off from the adhesive sheet. That is, the adhesive sheet is required to have low adhesiveness.

  In order to control the above two conflicting adhesive properties, an active energy ray-curable adhesive for re-peeling is used. The active energy ray-curable adhesive for re-peeling has high adhesiveness before irradiation with active energy rays, and the element pieces do not peel off from the adhesive sheet. And the element piece is easily peeled from the adhesive sheet.

  As a conventional example of an active energy ray-curable adhesive for re-peeling, an example using an active energy ray-reactive polymer containing a carbon-carbon double bond that reacts with an active energy ray in a molecular side chain has been reported (for example, Patent Document 1). In Patent Document 1, an acrylic polymer having a hydroxyl group is reacted with an isocyanate group that reacts with a hydroxyl group and a compound having a radical-reactive carbon-carbon double bond to produce an active energy ray-curable releasable pressure-sensitive adhesive. doing.

  However, in order to promote the reaction between the isocyanate group-containing compound and the hydroxyl group-containing polymer, a tin-based catalyst may be added, which has a problem of having a great influence on the environment. Moreover, the compound which has an isocyanate group and a radical reactive carbon-carbon double bond has the problem of reacting with water and deactivating. Furthermore, the compound having an isocyanate group and a radical-reactive carbon-carbon double bond has a problem that it has a large influence on the environment and the human body because it is volatile, and sufficient care is required for handling.

JP 2000-355678 A

  The subject of the present invention has a small impact on the environment and the human body, is easy to handle, can greatly change the adhesiveness before and after irradiation with active energy rays, can exhibit high adhesiveness before irradiation with active energy rays, An object is to provide an active energy ray-curable pressure-sensitive adhesive for re-peeling that can exhibit high peelability after irradiation with active energy rays.

The active energy ray-curable adhesive for re-peeling of the present invention is
An active energy ray-curable polymer (P),
The polymer (P) is obtained by reacting a carboxyl group-containing polymer (A) with an oxazoline group and an oxazoline group-containing compound (B) having a radical reactive carbon-carbon double bond.

  In preferable embodiment, the said carboxyl group-containing polymer (A) is a polymer comprised from the monomer component containing the acrylic ester as a main monomer, and a carboxyl group-containing monomer.

  In a preferred embodiment, the carboxyl group-containing monomer is at least one selected from (meth) acrylic acid and carboxyalkyl (meth) acrylate.

  In a preferred embodiment, the oxazoline group-containing compound (B) is 2-vinyl-2-oxazoline, 4-methyl-2-vinyl-2-oxazoline, 5-methyl-2-vinyl-2-oxazoline, 2- Vinyl-4,4-dimethyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 4-methyl-2-isopropenyl-2-oxazoline, 5-methyl-2-isopropenyl-2-oxazoline, and 2- It is at least one selected from isopropenyl-4,4-dimethyl-2-oxazoline.

  The active energy ray-curable releasable pressure-sensitive adhesive tape or sheet of the present invention has the active energy ray-curable releasable pressure-sensitive adhesive of the present invention on a substrate as an adhesive layer.

  In a preferred embodiment, the active energy ray-curable re-peeling pressure-sensitive adhesive tape or sheet of the present invention is for semiconductor wafer processing.

  According to the present invention, the impact on the environment and the human body is small, easy handling, can greatly change the adhesive before and after irradiation with active energy rays, can exhibit high adhesiveness before irradiation with active energy rays, The active energy ray-curable pressure-sensitive adhesive for re-peeling that can exhibit high peelability after irradiation with active energy rays can be provided.

≪A. Active energy ray-curable adhesive for re-peeling >>
The active energy ray-curable adhesive for re-peeling of the present invention contains an active energy ray-curable polymer (P).

  The active energy rays mean radiation such as α rays, β rays, γ rays, electron rays, neutron rays, X rays, ultraviolet rays, and the like.

  The polymer (P) can be cured by irradiation with active energy rays. By curing the polymer (P) by irradiation with active energy rays, the degree of crosslinking can be increased and the adhesive strength of the polymer (P) can be reduced.

  The polymer (P) is obtained by reacting a carboxyl group-containing polymer (A) with an oxazoline group-containing compound (B) having a radical reactive carbon-carbon double bond.

  As the carboxyl group-containing polymer (A), any appropriate polymer can be adopted as long as it has a carboxyl group. The carboxyl group-containing polymer (A) is preferably a polymer composed of a monomer component containing an acrylic ester as a main monomer and a carboxyl group-containing monomer.

  The glass transition temperature of the polymer (P) is preferably −70 ° C. or higher, more preferably −65 ° C. or higher, further preferably −60 ° C. or higher, particularly preferably −55 ° C. or higher, as the lower limit. The upper limit is preferably −10 ° C. or lower, more preferably −20 ° C. or lower, still more preferably −30 ° C. or lower, and particularly preferably −40 ° C. or lower.

  When the glass transition temperature of the polymer (P) exceeds −10 ° C., the tackiness of the pressure-sensitive adhesive is reduced. For example, when used for semiconductor wafer processing in semiconductor device manufacturing, so-called “chip jump” occurs during dicing. May occur.

  The polymer (P) preferably has a low content of a low molecular weight substance from the viewpoint of preventing contamination of a clean adherend. For this reason, the weight average molecular weight of the polymer (P) is preferably 350,000 or more, more preferably 450,000 or more as the lower limit, and preferably 1 million or less, more preferably 80,000 as the upper limit. 10,000 or less.

  Examples of the acrylic acid ester include an acrylic acid alkyl ester (for example, acrylic acid methyl ester, acrylic acid ethyl ester, acrylic acid propyl ester, acrylic acid isopropyl ester, acrylic acid butyl ester, acrylic acid isobutyl ester, and acrylic acid sec-butyl. Ester, t-butyl acrylate, pentyl acrylate, isopentyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, acrylic acid Nonyl ester, acrylic acid decyl ester, acrylic acid isodecyl ester, acrylic acid undecyl ester, acrylic acid dodecyl ester, acrylic The carbon number of the alkyl group, such as tridecyl ester, acrylic acid tetradecyl ester, acrylic acid hexadecyl ester, acrylic acid octadecyl ester, acrylic acid eicosyl ester, etc. is preferably 1-30, more preferably 4-18, Straight chain or branched alkyl alkyl ester) and acrylic acid cycloalkyl ester (for example, acrylic acid cyclopentyl ester, acrylic acid cyclohexyl ester, etc.).

  Only one type of acrylic ester may be used, or two or more types may be used in combination.

  Arbitrary appropriate content rates can be employ | adopted for the content rate of the acrylic ester in the monomer component which comprises a polymer (A) in the range which does not impair the effect of this invention. The content of the acrylic acid ester in the monomer component constituting the polymer (A) is preferably 40% by weight or more, more preferably 60% by weight or more, and still more preferably 80% by weight or more as a lower limit. The upper limit is preferably 97% by weight or less, more preferably 95% by weight or less, still more preferably 93% by weight or less, and particularly preferably 92% by weight. % Or less.

  When the content of the acrylic acid ester in the monomer component constituting the polymer (A) is less than 40% by weight, the peelability of the pressure-sensitive adhesive becomes too large, for example, when used for semiconductor wafer processing in semiconductor device manufacturing. There is a possibility that the pick-up property is lowered.

  When the content ratio of the acrylate ester in the monomer component constituting the polymer (A) exceeds 97% by weight, the curability of the polymer (P) by irradiation with active energy rays becomes low, for example, semiconductor wafer processing in semiconductor device manufacturing When used in, there is a possibility that the pick-up property may be lowered.

  Examples of the carboxyl group-containing monomer include (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. The carboxyl group-containing monomer is particularly preferably at least one selected from (meth) acrylic acid and carboxyalkyl (meth) acrylate.

  Only one type of carboxyl group-containing monomer may be used, or two or more types may be used in combination.

  Arbitrary appropriate content rates can be employ | adopted for the content rate of the carboxyl group-containing monomer in the monomer component which comprises a polymer (A) in the range which does not impair the effect of this invention. The content ratio of the carboxyl group-containing monomer in the monomer component constituting the polymer (A) is preferably 3% by weight or more, more preferably 5% by weight or more, and further preferably 7% by weight or more, as a lower limit. The upper limit is preferably 20% by weight or less, more preferably 18% by weight or less, still more preferably 16% by weight or less, and particularly preferably 15% by weight or more. % By weight or less.

  When the content ratio of the carboxyl group-containing monomer in the monomer component constituting the polymer (A) is less than 3% by weight, the curability of the polymer (P) by irradiation with active energy rays becomes low. For example, a semiconductor wafer in semiconductor device manufacture When used for processing, the pick-up property may be reduced.

  When the content of the carboxyl group-containing monomer in the monomer component constituting the polymer (A) exceeds 20% by weight, the amount of residual carboxyl groups in the pressure-sensitive adhesive increases, and the interaction with the adherend increases. As a result, the releasability decreases, and for example, when used for semiconductor wafer processing in the manufacture of semiconductor devices, the pick-up property may decrease.

  The monomer component constituting the polymer (A) may contain other monomers copolymerizable with the acrylate ester as necessary for the purpose of modifying cohesive strength, heat resistance and the like.

  Examples of other monomers include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, (meth ) Hydroxyl group-containing monomers such as 8-hydroxyoctyl acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate; maleic anhydride Acid anhydride monomers such as itaconic anhydride; styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, (meth ) Acrylio Sulfonic acid group-containing monomers shea naphthalene sulfonic acid; 2-hydroxyethyl acryloyl phosphate, etc. of a phosphate group-containing monomers; acrylamide; acrylonitrile; and the like.

  Other monomers may be used alone or in combination of two or more.

  Arbitrary appropriate content rates can be employ | adopted for the content rate of the other monomer in the monomer component which comprises a polymer (A) in the range which does not impair the effect of this invention. The content of other monomers in the monomer component constituting the polymer (A) is preferably 0% by weight or more as the lower limit, preferably 40% by weight or less, more preferably 35% as the upper limit. % Or less, and more preferably 30% by weight or less.

  When the content ratio of the other monomer in the monomer component constituting the polymer (A) exceeds 40% by weight, the peeling force between the pressure-sensitive adhesive and the adherend becomes too large. When used for wafer processing, the pick-up property may decrease, and the curability of the polymer (P) due to active energy ray irradiation becomes low. For example, when used for semiconductor wafer processing in semiconductor device manufacturing, the pick-up property is reduced. There is a risk.

  The polymer (A) is preferably obtained by polymerizing a monomer component containing an acrylate ester as a main monomer and a carboxyl group-containing monomer.

  Any appropriate method can be adopted as a polymerization method. Examples of the polymerization method include solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization and the like.

  Examples of the oxazoline group-containing compound (B) having an oxazoline group and a radical-reactive carbon-carbon double bond include 2-vinyl-2-oxazoline, 4-methyl-2-vinyl-2-oxazoline, 5-methyl- 2-vinyl-2-oxazoline, 2-vinyl-4,4-dimethyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 4-methyl-2-isopropenyl-2-oxazoline, 5-methyl-2- Examples include isopropenyl-2-oxazoline and 2-isopropenyl-4,4-dimethyl-2-oxazoline.

  Only 1 type may be used for an oxazoline group containing compound (B), and it may use 2 or more types together.

  The amount of the oxazoline group-containing compound (B) used is preferably 30 mol% or more, more preferably 50 mol%, as a lower limit with respect to the carboxyl group-containing monomer in the monomer component constituting the polymer (A). Or more, more preferably 70 mol% or more, particularly preferably 80 mol or more, and the upper limit is preferably 150 mol% or less, more preferably 100 mol% or less, still more preferably 95 mol% or less. It is less than mol%.

  When the amount of the oxazoline group-containing compound (B) used is less than 30 mol% with respect to the carboxyl group-containing monomer in the monomer component constituting the polymer (A), the amount of residual carboxyl groups in the adhesive increases. When the interaction with the adherend is increased, the peelability is lowered. For example, when used for semiconductor wafer processing in the manufacture of semiconductor devices, the pick-up property may be lowered.

  When the amount of the oxazoline group-containing compound (B) used exceeds 150 mol% with respect to the carboxyl group-containing monomer in the monomer component constituting the polymer (A), the residual oxazoline group-containing compound (B) in the pressure-sensitive adhesive When the amount of the low molecular weight substance derived therefrom and the amount of the low molecular weight substance are increased, the peeling force between the pressure-sensitive adhesive and the adherend becomes too large, for example, when used for semiconductor wafer processing in semiconductor device manufacturing, There is a possibility that the pick-up property may be deteriorated and the influence on the environment and human body may be increased due to volatilization of the residual oxazoline group-containing compound (B).

  Any appropriate reaction method can be adopted as a method of obtaining the polymer (P) by reacting the polymer (A) with the oxazoline group-containing compound (B). For example, the oxazoline group-containing compound (B) is added to the polymer (A) to any appropriate reaction conditions (for example, a reaction temperature in the range of 20 to 70 ° C., a reaction time of 10 to 100 hours in air). And a method of performing an addition reaction.

  The polymer (P) can be made into a cured product by crosslinking reaction by irradiation with active energy rays.

  In order to cause the polymer (P) to undergo a crosslinking reaction by irradiation with active energy rays, any suitable crosslinking agent and any suitable photopolymerization initiator are preferably used for the polymer (P).

  Examples of the crosslinking agent include polyisocyanate compounds, epoxy compounds, aziridine compounds, melamine-based crosslinking agents, and the like. By using a cross-linking agent, it is possible to adjust the adhesive strength of the adhesive before irradiation with active energy rays and the adhesive strength of the adhesive after irradiation with active energy rays.

  Only 1 type may be used for a crosslinking agent and it may use 2 or more types together.

  Any appropriate amount of the cross-linking agent can be adopted depending on the type of the polymer (P). The amount of the crosslinking agent used is, for example, preferably 0.01% by weight or more, more preferably 0.1% by weight or more, preferably 0.1% by weight or more, preferably as the upper limit, relative to the polymer (P). It is 20 weight% or less, More preferably, it is 10 weight% or less.

  Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α′-dimethylacetophenone, 2-methyl-2-hydroxypropio Α-ketol compounds such as phenone and 1-hydroxycyclohexyl phenyl ketone; methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1- [4- (methylthio) Acetophenone compounds such as -phenyl] -2-morpholinopropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether and anisoin methyl ether; ketal compounds such as benzyldimethyl ketal; 2-naphthalenesulfonyl chloride Aromatic sulfonyl chloride compounds such as 1; -phenone-1,1-propanedione-2- (o-ethoxycarbonyl) oxime; photoactive oxime compounds such as benzophenone, benzoylbenzoic acid, 3,3′-dimethyl Benzophenone compounds such as -4-methoxybenzophenone; thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2 Thioxanthone compounds such as 1,4-diethylthioxanthone and 2,4-diisopropylthioxanthone; camphorquinone; halogenated ketone; acyl phosphinoxide; acyl phosphonate;

  Only 1 type may be used for a photoinitiator and it may use 2 or more types together.

  Arbitrary appropriate quantity can be employ | adopted for the usage-amount of a photoinitiator by the kind etc. of polymer (P). The use amount of the photopolymerization initiator is, for example, as a lower limit for the polymer (P), preferably 0.01% by weight or more, more preferably 0.05% by weight or more, Preferably it is 20 weight% or less, More preferably, it is 10 weight% or less.

  The pressure-sensitive adhesive may contain other components in addition to the polymer (P) as long as the effects of the present invention are not impaired.

  Examples of other components include compounds that react with carboxyl groups; active energy ray-curable monomers; active energy ray-curable oligomers; additives such as tackifiers and anti-aging agents;

  A compound that reacts with a carboxyl group can be used, for example, to adjust the amount of residual carboxyl group present in the pressure-sensitive adhesive. Any appropriate amount of the compound that reacts with the carboxyl group may be used as long as the effects of the present invention are not impaired.

  Examples of the compound that reacts with a carboxyl group include an amino group-containing compound, an epoxy group-containing compound, an isocyanate group-containing compound, and a carbodiimide group-containing compound.

  Only 1 type may be used for the compound which reacts with a carboxyl group, and 2 or more types may be used together.

  The active energy ray-curable monomer and the active energy ray-curable oligomer can be used, for example, to adjust the adhesive strength before irradiation with active energy rays and the adhesive strength after irradiation with active energy rays.

  Examples of the active energy ray-curable monomer include urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetra (meth). Examples include acrylate, dipentaerystol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and 1,4-butanediol di (meth) acrylate.

  Only one type of active energy ray-curable monomer may be used, or two or more types may be used in combination.

  Examples of the active energy ray-curable oligomer include urethane oligomers, polyether oligomers, polyester oligomers, polycarbonate oligomers, polybutadiene oligomers, and the like.

  Only one type of active energy ray-curable oligomer may be used, or two or more types may be used in combination.

  The molecular weight of the active energy ray-curable oligomer is preferably 100 to 30000.

  The active energy ray-curable monomer and the active energy ray-curable oligomer can be used in any appropriate amount as long as the effects of the present invention are not impaired. The total amount of the active energy ray-curable monomer and the active energy ray-curable oligomer used is preferably 5% by weight or more, more preferably 40% or less as a lower limit with respect to the polymer (P), for example. The upper limit is preferably 500% by weight or less, and more preferably 150% by weight or less.

  The acid value of the pressure-sensitive adhesive is preferably 10 or less. When the acid value of the pressure-sensitive adhesive exceeds 10, the amount of residual carboxyl groups in the pressure-sensitive adhesive increases, and the releasability decreases due to the increased interaction with the adherend. For example, in the manufacture of semiconductor devices When used for semiconductor wafer processing, the pick-up property may be reduced.

  The acid value of the pressure-sensitive adhesive can be adjusted by adjusting the amount used of various compounds such as the oxazoline group-containing compound (B) that can be used in forming the pressure-sensitive adhesive.

  The acid value can be evaluated according to JIS K 0070-1992 (potentiometric titration method).

  Arbitrary appropriate methods can be employ | adopted as a method of forming an adhesive. Examples of the method of forming the pressure-sensitive adhesive as the pressure-sensitive adhesive layer include a method of directly forming the pressure-sensitive adhesive layer on the substrate and a method of transferring the pressure-sensitive adhesive layer provided on the separator onto the substrate.

≪B. Active energy ray curable adhesive tape or sheet for re-peeling »
The active energy ray-curable releasable pressure-sensitive adhesive tape or sheet of the present invention has the active energy ray-curable releasable pressure-sensitive adhesive of the present invention on a substrate as an adhesive layer.

  Arbitrary appropriate thickness can be employ | adopted for the thickness of an adhesive layer. The thickness of the pressure-sensitive adhesive layer is, for example, preferably 1 μm or more as a lower limit, more preferably 2 μm or more, still more preferably 5 μm or more, and the upper limit is preferably 50 μm or less, more preferably. It is 30 μm or less, more preferably 25 μm or less. When the thickness of the pressure-sensitive adhesive layer is within the above range, chipping of the chip cut surface can be prevented and high adhesiveness and high peelability can be well-balanced when used for semiconductor wafer processing in semiconductor device manufacturing.

  The active energy ray-curable releasable pressure-sensitive adhesive tape or sheet of the present invention can have an antistatic ability. By providing the active energy ray-curable adhesive tape or sheet for re-peeling of the present invention with antistatic ability, the circuit is generated by the generation of static electricity at the time of adhesion and peeling and the charging of the workpiece (semiconductor wafer, etc.). It can be prevented from being destroyed.

  Examples of a method for imparting antistatic ability to the active energy ray-curable pressure-sensitive adhesive tape or sheet of the present invention include a method of adding an antistatic agent or a conductive substance to a substrate or a pressure-sensitive adhesive layer, a charge transfer complex or a metal Examples thereof include a method of attaching a conductive layer made of a film or the like on a substrate. As these methods, for example, a method in which impurity ions that may change the quality of a semiconductor wafer when used for semiconductor wafer processing in semiconductor device manufacture is less likely to be generated.

  As a conductive substance (conductive filler) blended for the purpose of imparting conductivity and improving thermal conductivity, spherical, needle-like, and flaky shapes such as silver, aluminum, gold, copper, nickel, and conductive alloys Examples thereof include metal powders, metal oxides such as alumina, amorphous carbon black, and graphite.

  The active energy ray-curable releasable pressure-sensitive adhesive tape or sheet of the present invention may be protected by a separator. The active energy ray-curable pressure-sensitive adhesive tape or sheet for re-peeling of the present invention can be wound into a roll while being protected by a separator. The separator has a function as a protective material for protecting the active energy ray-curable re-peeling pressure-sensitive adhesive tape or sheet of the present invention until practical use. Examples of the separator include polyethylene terephthalate (PET), polyethylene, polypropylene, a plastic film whose surface is coated with a release agent such as a fluorine-type release agent and a long-chain alkyl acrylate-type release agent, and paper.

  The active energy ray-curable pressure-sensitive adhesive tape or sheet for re-peeling of the present invention may be subjected to a back surface treatment, for example, when it is not protected by a separator. The back surface treatment can be performed using a release agent such as a silicone release agent or a long-chain alkyl acrylate release agent.

<< B-1. Base material >>
The base material is the strength matrix of the active energy ray-curable releasable pressure-sensitive adhesive tape or sheet of the present invention.

  The substrate preferably has active energy ray permeability. For example, when manufacturing a semiconductor device using the active energy ray-curable removable pressure-sensitive adhesive tape or sheet of the present invention, it is included in the pressure-sensitive adhesive layer of the active energy ray-curable removable pressure-sensitive adhesive tape or sheet of the present invention. This is because the polymer (P) is preferably cured by irradiation with active energy rays before picking up the semiconductor chip. In this case, the active energy ray irradiation may be performed at any appropriate timing before picking up the semiconductor chip.

  Arbitrary appropriate thickness can be employ | adopted for the thickness of a base material. Preferably, it is 5 micrometers-200 micrometers.

  Any appropriate material can be adopted as the material for the base material as long as the effects of the present invention can be exhibited. Examples of the base material include low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene, ultra high molecular weight polyethylene, random copolymer polypropylene, block copolymer polypropylene, and homopolypropylene. Len, polybutene, polymethylpentene, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer Polyolefin resins such as ethylene-hexene copolymer and ionomer resin; Styrene resins such as polystyrene, ABS resin, AS resin, AAS resin, ACS resin, AES resin, MS resin, SMA resin, MBS resin; polyvinyl chloride Chlorine such as polyvinylidene chloride Fats; Urethane resins such as polyurethane; Polyester resins such as polyethylene terephthalate and polyethylene naphthalate; Polyamide, fully aromatic polyamide (aramid), polycarbonate, polyimide, polyetheretherketone, polyetherimide, polyphenylsulfide, etc. Examples include rearing plastic; glass; glass cloth; fluororesin; cellulose resin; silicone resin; metal (foil); Examples of the material for the base material include cross-linked materials such as the above-mentioned resins.

  The base material may be formed of only one kind of material or may be formed of two or more kinds of materials. The substrate may be a single layer or two or more types.

  As the substrate, an unstretched substrate may be used, or a substrate subjected to a stretching process such as uniaxial stretching or biaxial stretching may be used.

  When a base material that has been subjected to stretching treatment is used, for example, when used for semiconductor wafer processing in semiconductor device manufacturing, the base material is thermally shrunk after dicing so that the adhesive area between the pressure-sensitive adhesive layer and the adherend is reduced. The semiconductor chip can be easily collected.

  The surface of the base material may be subjected to any appropriate surface treatment in order to improve adhesion and retention with an adjacent layer. Examples of such surface treatment include chemical or physical treatment such as chromic acid treatment, ozone exposure, flame exposure, high-voltage impact exposure, ionizing radiation treatment, etc .; coating treatment with a primer (for example, an adhesive substance described later); Etc.

  In order to impart an antistatic ability to the base material, a deposited layer of a conductive substance made of a metal, an alloy, an oxide thereof, or the like can be provided on the base material. The thickness of such a vapor deposition layer is preferably 30 to 500 mm.

≪C. Production method of active energy ray-curable adhesive tape or sheet for re-peeling >>
The substrate can be formed by any appropriate film forming method. Examples of such a film forming method include a calendar film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T-die extrusion method, a co-extrusion method, and a dry lamination method.

  Next, the composition containing the pressure-sensitive adhesive of the present invention is applied onto a substrate and dried (heat-crosslinked as necessary) to form a pressure-sensitive adhesive layer. Examples of the method for applying the composition containing the pressure-sensitive adhesive include roll coating, screen coating, and gravure coating. The application may be performed directly on the substrate, or may be applied to a release paper or the like whose surface has been subjected to a release treatment and then transferred to the substrate.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples at all. In addition, the test and evaluation method in an Example etc. are as follows. Moreover, a part means a weight part.

<Measurement of glass transition temperature>
Using a dynamic viscoelasticity measuring device “ARES” manufactured by Rheometric Co., Ltd., using a jig with a sample thickness of about 1.5 mm and a φ7.9 mm parallel plate, a frequency of 1 Hz, and a heating rate of 5 ° C./min. The temperature at the peak point of the obtained loss modulus was taken as the glass transition temperature.

<Measurement of adhesive strength before irradiation with active energy rays>
An adhesive sheet (20 mm × 100 mm) is placed on the surface of a silicon mirror wafer (trade name “CZN <100> 2.5-3.5” (4 inches), manufactured by Shin-Etsu Semiconductor Co., Ltd.), a hand roller in a 23 ° C. atmosphere. Was reciprocated once to make a crimp.
After 30 minutes at 23 ° C., the force required for the peeling was measured (180 ° peeling, tensile speed 300 mm / min, 23 ° C. × 50% RH atmosphere).

<Measurement of adhesive strength after irradiation with active energy rays>
An adhesive sheet (20 mm × 100 mm) is placed on the surface of a silicon mirror wafer (trade name “CZN <100> 2.5-3.5” (4 inches), manufactured by Shin-Etsu Semiconductor Co., Ltd.), a hand roller in a 23 ° C. atmosphere. Was reciprocated once to make a crimp.
After 30 minutes at 23 ° C., an ultraviolet ray irradiation device (trade name “UM810”: manufactured by Nitto Seiki Co., Ltd.) was used to irradiate ultraviolet rays from the adhesive sheet surface side (light quantity: 450 mJ / cm ² ). The force required for peeling was measured (180 degree peeling, tensile speed 300 mm / min, 23 ° C. × 50% RH atmosphere).

[Example 1]
In a reaction vessel equipped with a cooling pipe, a nitrogen introduction pipe, a thermometer, and a stirring device, 90 parts of 2-ethylhexyl acrylate (hereinafter referred to as “2EHA”), 10 parts of acrylic acid (hereinafter referred to as “AA”), 0.2 parts of benzoyl peroxide and 150 parts of ethyl acetate were added and polymerized in a nitrogen stream at 61 ° C. for 6 hours to obtain an acrylic polymer A.
To this acrylic polymer A, 12.1 parts of 2-vinyl-2-oxazoline (hereinafter referred to as “VO”) (90 mol% with respect to AA) was added, and an addition reaction treatment was performed at 50 ° C. for 48 hours in an air stream. As a result, an acrylic polymer A ′ was obtained. The glass transition temperature of the acrylic polymer A ′ was −49 ° C.
Next, for 100 parts of acrylic polymer A ′, 3 parts of a polyisocyanate compound (trade name “Coronate L”, manufactured by Nippon Polyurethane Co., Ltd.) and a photopolymerization initiator (trade name “Irgacure 651”, Ciba Special) 5 parts) (manufactured by T Chemicals) was added to prepare an adhesive solution.
The pressure-sensitive adhesive solution was coated on the surface of the polyester film (thickness: 50 μm) subjected to the silicone release treatment so that the thickness after drying was 30 μm, and the temperature was 120 ° C. for 3 minutes. It dried and the adhesive layer was formed.
Adhesive surface of the pressure-sensitive adhesive layer is pasted with an ethylene-vinyl acetate copolymer film (thickness: 115 μm) that has been subjected to surface oxidation treatment by a corona discharge method, the pressure-sensitive adhesive layer is transferred, and pressure-sensitive adhesive sheet (1) Was made.
Various evaluation was performed about the obtained adhesive sheet (1). The results are shown in Table 1.
In addition, the meaning of the abbreviation described in Table 1 is as follows.
2EHA: 2-ethylhexyl acrylate EA: ethyl acrylate BA: n-butyl acrylate AA: acrylic acid VO: 2-vinyl-2-oxazoline

[Examples 2 to 6]
Except having changed into the composition and content shown in Table 1, it carried out similarly to Example 1, and produced the adhesive sheets (2)-(6).
Various evaluation was performed about the obtained adhesive sheets (2)-(6). The results are shown in Table 1.

[Comparative Examples 1-2]
Except having changed into the composition and content shown in Table 1, it carried out similarly to Example 1, and produced the adhesive sheets (C1)-(C2).
Various evaluation was performed about the obtained adhesive sheet (C1)-(C2). The results are shown in Table 1.

  As shown in Table 1, the active energy ray-curable pressure-sensitive adhesive for re-peeling of the present invention can greatly change the adhesiveness before and after irradiation with active energy rays, and can exhibit high adhesiveness before irradiation with active energy rays. It can be seen that high peelability can be exhibited after irradiation with active energy rays. In addition, the active energy ray-curable pressure-sensitive adhesive for re-peeling of the present invention does not use the tin-based catalyst used in the conventional active energy ray-curable pressure-sensitive adhesive for re-peeling, so that it does not adversely affect the environment. I understand. Furthermore, in the active energy ray-curable pressure-sensitive adhesive for re-peeling of the present invention, the remaining of volatile substances in the pressure-sensitive adhesive can be suppressed, so that it does not adversely affect the environment and the human body and is easy to handle. I understand.

The active energy ray-curable pressure-sensitive adhesive for re-peeling of the present invention can be suitably used, for example, for dicing a workpiece (semiconductor wafer or the like) when manufacturing a semiconductor device.

Claims (5)

An active energy ray-curable polymer (P),
The polymer (P) is a carboxyl group-containing polymer obtained by solution polymerization (A), oxazoline group and a radical reactive carbon - Re resulting et al by reacting a oxazoline group-containing compound (B) having a carbon-carbon double bond ,
The carboxyl group-containing polymer (A) is a polymer composed of a monomer component containing an acrylate ester as a main monomer and a carboxyl group-containing monomer,
The acrylic acid ester is an alkyl alkyl ester having 4 to 18 carbon atoms in the alkyl group,
The content of the acrylic ester in the monomer component is 60% by weight to 97% by weight,
The content of the carboxyl group-containing monomer of the monomer component is Ru 3 wt% to 20 wt% der,
Active energy ray curable adhesive for re-peeling. The active energy ray-curable pressure-sensitive adhesive for re-peeling according to claim 1 , wherein the carboxyl group-containing monomer is at least one selected from (meth) acrylic acid and carboxyalkyl (meth) acrylate. The oxazoline group-containing compound (B) is 2-vinyl-2-oxazoline, 4-methyl-2-vinyl-2-oxazoline, 5-methyl-2-vinyl-2-oxazoline, 2-vinyl-4,4- Dimethyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 4-methyl-2-isopropenyl-2-oxazoline, 5-methyl-2-isopropenyl-2-oxazoline, and 2-isopropenyl-4,4 The active energy ray-curable adhesive for re-peeling according to claim 1 or 2 , which is at least one selected from -dimethyl-2-oxazoline. An active energy ray-curable releasable pressure-sensitive adhesive tape or sheet comprising the active energy ray-curable releasable pressure-sensitive adhesive according to any one of claims 1 to 3 on a substrate as an adhesive layer. The active energy ray-curable adhesive tape or sheet for re-peeling according to claim 4 , which is used for semiconductor wafer processing.