Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
  • C09J11/02—Non-macromolecular additives
  • C09J11/06—Non-macromolecular additives organic
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
  • C09J133/04—Homopolymers or copolymers of esters
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J7/00—Adhesives in the form of films or foils
  • C09J7/20—Adhesives in the form of films or foils characterised by their carriers
  • C09J7/22—Plastics; Metallised plastics
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J7/00—Adhesives in the form of films or foils
  • C09J7/20—Adhesives in the form of films or foils characterised by their carriers
  • C09J7/29—Laminated material
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J7/00—Adhesives in the form of films or foils
  • C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
  • C09J7/38—Pressure-sensitive adhesives [PSA]
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
  • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
  • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26

Definitions

• the present invention relates to an adhesive tape and a processing method.
• a tape for semiconductor wafer processing is applied to the adherends, and the adherends are separated during dicing. Temporarily fix. This can prevent chip skipping during singulation.
• the semiconductor wafer processing tape is expanded, and the individualized adherends are picked up (separated) from the semiconductor wafer processing tape.
• adhesive tapes in which an adhesive layer that hardens when exposed to ultraviolet rays is coated on a film base material that is transparent to ultraviolet rays are mainly used.
• the adhesive layer is irradiated with ultraviolet rays after dicing to promote a curing reaction and reduce the adhesive strength of the adhesive layer. Can be easily picked up.
• the individualized adherend is pushed up with a push-up pin from the back side of the adhesive tape that is not in contact with the adherend, and picked up.
• the adhesive tape is required to have high wettability to the adherend.
• the adhesive tape when applying the adhesive tape to the adherend, if the wettability of the adhesive to the adherend is not good, the adhesive will not be able to follow the steps of the adherend and air bubbles will form. This may cause failure of curing of the adhesive due to oxygen inhibition or the like during ultraviolet irradiation, and the adhesive may remain on the adherend without being cured. In addition, if the adhesion to the adherend is insufficient, cutting water may enter between the adherend and the adhesive tape during dicing, contaminating the adherend, or even breaking the adherend into pieces. It scatters.
• the thickness of the adhesive layer is increased, low molecular weight components and tackifiers are added to increase the adhesive strength, and the elastic modulus of the adhesive layer is reduced.
• One possible method is to increase the adhesive strength.
• the adhesive may be melted by the frictional heat generated by the rotation of the blade during dicing and scraped up, resulting in adhesive debris adhering to the adherend.
• the adhesive is cured by UV irradiation while it is being scraped up, the individualized adherends will be fixed to the adhesive tape, making it difficult to pick up at low pin heights, or even if it is picked up, The adhesive itself may be destroyed because it cannot be peeled off at the interface with the adherend, and the adhesive may remain on the adherend.
• Patent Document 1 As a means to solve such adhesive residue and improve pick-up properties, for example, as in Patent Document 1, a large amount of a relatively low molecular weight ultraviolet curable resin component is blended to significantly increase the adhesive strength after ultraviolet irradiation. A method is disclosed for reducing this.
• an ionomer resin containing a crosslinked structure formed by metal ions is sometimes used, for example, as in Patent Documents 2 and 3.
• ionomer resin has a lower elastic modulus near the temperature at which semiconductors are processed, so it can easily conform to adherends with steps, and prevents adhesive residue due to chip flying or poor curing of the adhesive layer. It can be suppressed.
• ionomer resins do not lose their shape as much as polyolefin base materials because of their crosslinked structure with metal ions. Therefore, there is an advantage that, for example, the occurrence of whiskers after dicing can be suppressed.
• Patent Document 1 by blending a large amount of a relatively low molecular weight ultraviolet curable resin component, the adhesive becomes too hard after being irradiated with ultraviolet rays. Therefore, the adhesive cannot withstand the deformation of the tape when it is picked up, causing it to crack into the shape of a pin, which may cause adhesive residue.
• the present invention has been made in view of the above-mentioned problems, and provides an adhesive tape and a processing method using the same, which can suppress a decrease in adhesive strength in a high-temperature environment while maintaining high initial adhesive strength and low contamination.
• the purpose is to provide
• an adhesive layer containing carboxyl groups at a certain concentration or more that is, containing a (meth)acrylic polymer and having a predetermined acid value
• a group containing an ionomer resin that by providing a protective layer between the adhesive tape and the material layer, it is possible to suppress the decrease in adhesive strength of the adhesive tape in a high-temperature environment, and have completed the present invention.
• the present invention is as follows. [1] It has a structure in which a base material layer, a protective layer, and an adhesive layer are laminated in this order,
• the base layer contains an ionomer resin
• the adhesive layer contains (meth)acrylic polymer A and a photopolymerization initiator
• the adhesive layer has an acid value of 10 mgKOH/g or more.
• Adhesive tape [2]
• the protective layer contains at least one selected from the group consisting of polyolefin polymers, (meth)acrylic polymers, and styrene polymers.
• the (meth)acrylic polymer A contains a polymerizable double bond, The adhesive tape according to [1] or [2].
• the (meth)acrylic polymer A has a structural unit represented by the following formula (1), The adhesive tape according to any one of [1] to [3].
• R 1 represents an organic group having a polymerizable double bond
• R 2 represents a single bond or an organic group having 1 to 6 carbon atoms
• R 3 represents a hydrogen atom or a methyl group.
• the adhesive layer further contains an isocyanate compound, The content of the isocyanate compound is 3 parts by weight or less based on 100 parts by weight of the (meth)acrylic polymer A.
• the adhesive layer further contains an amine compound.
• the ionomer resin includes a (meth)acrylic ionomer resin, The adhesive tape according to any one of [1] to [6].
• the thickness of the protective layer is 0.1 to 10 ⁇ m, The adhesive tape according to any one of [1] to [7].
• the ratio F'/F is 0. .80 or higher; The adhesive tape according to any one of [1] to [8].
• the adherend is a semiconductor wafer, a semiconductor device, or a variety of semiconductor packages, Processing method.
• an adhesive tape that can suppress a decrease in adhesive strength in a high-temperature environment while maintaining high initial adhesive strength and low contamination, and a processing method using the same.
• this embodiment an embodiment of the present invention (hereinafter referred to as “this embodiment”) will be described in detail.
• the present invention is not limited to the following embodiments, and various modifications can be made without departing from the gist thereof.
• the adhesive tape of this embodiment has a structure in which a base layer, a protective layer, and an adhesive layer are laminated in this order, the base layer contains an ionomer resin, and the adhesive layer ( It contains meth)acrylic polymer A and a photopolymerization initiator, and the acid value of the adhesive layer is 10 mgKOH/g or more.
• Carboxyl groups derived from the matrix polymer present in the adhesive layer of the adhesive tape can have the function of improving wettability to adherends and improving adhesive strength before UV irradiation.
• an adhesive tape containing an ionomer resin in its base layer is stored for a long period of time in a high-temperature environment, there is a problem in that the adhesiveness of the adhesive layer decreases over time.
• the reason for this is not particularly limited, but it is believed that metal ions migrate from the base material layer to the adhesive layer and coordinate with carboxyl groups in the adhesive layer, increasing the male ratio of the adhesive and decreasing the adhesive force. It can be assumed.
• a protective layer is provided between the base layer containing the ionomer resin and the adhesive layer having a predetermined acid value.
• the present embodiment has excellent initial adhesive strength and adhesive strength stability during high-temperature storage, and allows semiconductor chips to be easily peeled off after dicing, allowing semiconductor processing with low risk of chip contamination.
• adhesive tape for
• the ratio F'/F is preferably 0. .80 or more, more preferably 0.85 to 2.0, even more preferably 0.90 to 2.0.
• the ratio F'/F is within the above range, the adhesive strength stability during high temperature storage tends to be further improved.
• the base material layer contains an ionomer resin.
• ionomer resin has a lower elastic modulus near the temperature at which semiconductors are processed, so it can easily conform to adherends with steps, and prevents adhesive residue due to chip flying or poor curing of the adhesive layer. It can be suppressed.
• the ionomer resin has a crosslinked structure with metal ions, it can maintain shape stability even when exposed to temporary or local high temperatures such as during semiconductor processing. On the other hand, for example, in the case of a polyolefin base material, the shape is greatly distorted and whiskers occur after dicing.
• the ionomer resin is not particularly limited as long as it is a predetermined polymer intermolecularly bonded with metal ions, and examples include polyolefin ionomers, (meth)acrylic ionomers, polystyrene ionomers, and polyester ionomers. . These ionomer resins may be used alone or in combination of two or more. Among these, polyolefin ionomers and (meth)acrylic ionomers are preferred, and (meth)acrylic ionomers are more preferred. By using such an ionomer resin, initial adhesive strength, low staining property, and adhesive strength retention performance in a high temperature environment tend to be further improved.
• the above-mentioned polyolefin ionomer is not particularly limited, but includes, for example, ethylene-methacrylate copolymer, ethylene-acrylate copolymer, ethylene-methacrylate-acrylic ester copolymer, and the like.
• the acrylic ionomer is not particularly limited, but includes, for example, acrylic ester-acrylate copolymer, acrylic ester-methacrylate copolymer, methacrylic ester-acrylate copolymer, and methacrylic ester. -methacrylate copolymers, etc.
• the polystyrene ionomer is not particularly limited, but examples include styrene-styrene sulfonate copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, and styrene-styrene carboxylate copolymer. and styrene-N-methyl 4-vinylpyridinium salt copolymers.
• the polyester ionomer is not particularly limited, but examples include sulfoterephthalate copolymer polyethylene terephthalate, sulfoisophthalate copolymer polyethylene terephthalate, sulfoterephthalate copolymer polybutylene terephthalate, sulfoisophthalate copolymer polybutylene terephthalate, etc. can be mentioned.
• the metal ions constituting the salt of the ionomer resin are not particularly limited, but include, for example, monovalent metal ions such as sodium ions and lithium ions; divalent metal ions such as zinc ions, calcium ions, and magnesium ions; aluminum ions, etc. Examples include trivalent metal ions, and zinc ions are preferred.
• the polymer and metal ion in the ionomer resin can be used in any combination based on the valence of the ionic functional group and metal ion in the polymer.
• the base layer may contain other additives such as known plasticizers, heat stabilizers, colorants, organic lubricants, inorganic lubricants, surfactants, and processing aids, as necessary.
• the content of the ionomer resin in the base layer is preferably 80% by weight or more, more preferably 85% by weight or more, based on the entire base layer.
• the upper limit of the content of the ionomer resin is not particularly limited, and is, for example, 100% by weight or 95% by weight.
• Materials other than the ionomer resin constituting the base layer are not particularly limited, but include, for example, polyvinyl chloride, polyethylene terephthalate, ethylene-vinyl acetate copolymer, ethylene-acrylic acid-acrylic acid ester film, and ethylene-ethyl acrylate. Examples include copolymers, polyethylene, polypropylene, propylene copolymers, and ethylene-acrylic acid copolymers.
• the base material layer may be a mixture, copolymer, or laminate of the ionomer resin and these resins.
• the thickness of the base layer is preferably 10 to 500 ⁇ m, preferably 50 to 200 ⁇ m, and more preferably 70 to 160 ⁇ m.
• the base material layer may be a single layer or a multilayer structure consisting of two or more layers.
• the base material layer is composed of a plurality of base films, it is preferable to adjust the thickness of the entire base material layer to be within the above range.
• the base layer may be subjected to chemical or physical surface treatment, if necessary, in order to improve its adhesion with the protective layer.
• surface treatment include corona treatment, chromic acid treatment, ozone exposure, flame exposure, high voltage electric shock exposure, and ionizing radiation treatment.
• the adhesive tape of this embodiment has a protective layer between the base layer and the adhesive layer.
• the protective layer can suppress the transfer of metal ions from the base material layer to the adhesive layer, and can suppress the adhesive strength from decreasing when the adhesive tape is stored at high temperatures.
• the acid value of the protective layer is not particularly limited, but is preferably less than 10 mgKOH/g, more preferably 0.1 to 9.0 mgKOH/g, and even more preferably 0.5 to 8.0 mgKOH/g.
• the acid value of the protective layer is low, metal ions are difficult to penetrate from the base layer to the protective layer in the first place, and metal component migration itself tends to be suppressed.
• the acid value of the protective layer is high, metal ions are relatively likely to permeate from the base layer to the protective layer, but the protective layer can trap metal components. Therefore, in either case, transfer of the metal component from the base layer to the adhesive layer tends to be suppressed. As a result, while maintaining high initial adhesive strength and low contamination, the decrease in adhesive strength in a high-temperature environment tends to be further suppressed.
• the protective layer has the ability to maintain adhesive strength to the base material layer and the adhesive layer, and the ability to prevent melting during high-temperature storage.
• the resin contained in the protective layer is preferably at least one selected from the group consisting of polyolefin polymers, (meth)acrylic polymers, and styrene polymers, and (meth)acrylic resins are preferably used. is more preferable.
• Examples of (meth)acrylic resins include, but are not limited to, ethylene-vinyl acetate copolymer, ethylene-acrylic acid-acrylic acid ester film, ethylene-ethyl acrylate copolymer, polyethylene, polypropylene, and propylene copolymer.
• Examples include ethylene-acrylic acid copolymers, acrylic ester-methacrylic ester copolymers, (meth)acrylic ester-(meth)acrylic acid copolymers, and other (meth)acrylic ester copolymers. It will be done.
• Styrenic polymers are not particularly limited, but include, for example, styrene-acrylate copolymers, styrene-butadiene block copolymers, maleic anhydride-modified hydrogenated styrene-butadiene-styrene block copolymers, and the like.
• the protective layer may be a single layer or a multilayer structure consisting of two or more layers.
• the entire protective layer has an acid value of less than 10 mg/gKOH.
• the protective layer may contain other additives such as known plasticizers, heat stabilizers, colorants, organic lubricants, inorganic lubricants, surfactants, and processing aids, as necessary.
• it may contain a salt such as a quaternary ammonium salt, or may contain a conductive component such as conductive polyacetylene, metal powder, carbon powder, or carbon nanotube.
• salts such as quaternary ammonium salts and conductive components are not included.
• the thickness of the protective layer is preferably 0.1 to 10 ⁇ m, more preferably 0.3 to 5.0 ⁇ m, even more preferably 0.5 to 4.0 ⁇ m, even more preferably 0.5 ⁇ m. ⁇ 3.0 ⁇ m.
• the thickness of the protective layer is within the above range, the initial adhesive strength, low staining property, and adhesive strength retention in a high-temperature environment tend to be further improved. In addition to this, the followability to the adherend and the adhesion to the base material layer and the adhesive layer tend to be further improved.
• the protective layer has a multilayer structure, it is preferable that the entire protective layer has the same thickness.
• the adhesive layer contains a (meth)acrylic polymer and a photopolymerization initiator, and has an acid value of 10 mgKOH/g or more.
• the (meth)acrylic polymer contained in the adhesive layer is referred to as (meth)acrylic polymer A.
• the acid value of the adhesive layer is 10 mgKOH/g or more, preferably 10 to 150 mgKOH/g, more preferably 20 to 100 mgKOH/g, and still more preferably 30 to 80 mgKOH/g.
• the acid value of the adhesive layer is 10 mgKOH/g or more, the adhesive strength before ultraviolet irradiation is further improved.
• the acid value of the adhesive layer is 120 mgKOH/g or less, the compatibility of each component is further improved, and the adhesive strength after ultraviolet irradiation tends to be further reduced.
• the chip pickup efficiency tends to be further improved due to the decrease in adhesive strength after irradiation with ultraviolet rays.
• the acid value of the adhesive layer can be adjusted by the amount of (meth)acrylic polymer A and amine compound used, which will be described later. Further, the acid value of the adhesive layer can be measured by the method described in Examples.
• the thickness of the adhesive layer is preferably 1.0 to 250 ⁇ m, more preferably 2.0 to 50 ⁇ m, and still more preferably 4.0 to 40 ⁇ m.
• the thickness of the adhesive layer is 1.0 ⁇ m or more, the adhesive force is further improved, and scattering of semiconductor chips divided by expansion tends to be suppressed.
• the thickness of the adhesive layer is 250 ⁇ m or less, the mold releasability tends to be further improved.
• the total thickness of the adhesive tape when used as an adhesive tape for semiconductor wafer processing is preferably 60 to 250 ⁇ m, more preferably 70 to 200 ⁇ m, and even more preferably 70 to 180 ⁇ m.
• (Meth)acrylic polymer A preferably has a carboxyl group.
• the (meth)acrylic polymer A having a carboxyl group contributes to improving the adhesive strength before UV irradiation and decreasing the adhesive strength after UV irradiation.
• the (meth)acrylic polymers A may be used alone or in combination of two or more.
• the adhesive layer of the present embodiment may further contain a (meth)acrylic polymer not having a carboxyl group, if necessary.
• the polymerization form of the (meth)acrylic polymer A is not particularly limited, and examples thereof include a homopolymer, a random copolymer, a block copolymer, and a graft copolymer.
• the polymerization shape of the (meth)acrylic polymer A is not particularly limited, and examples thereof include a linear polymer, a branched polymer, and a crosslinked polymer. Among these, it is preferable to have a crosslinked shape. By using such a polymer, the cohesive force of the pressure-sensitive adhesive layer is improved, the adhesion to the adherend is further improved, and contamination tends to be further reduced.
• the crosslinked or branched polymer may be one in which some of the polymerizable double bonds of a linear polymer are bonded together by aging or the like.
• the content of (meth)acrylic polymer A is preferably 60 to 99% by mass, more preferably 70 to 99% by mass, even more preferably 80 to 98% by mass, based on the total amount of the adhesive layer. be.
• the content of (meth)acrylic polymer A is within the above range, the adhesive strength before UV irradiation tends to be further improved, and the adhesive strength after UV irradiation tends to be further reduced.
• the structural units possessed by (meth)acrylic polymer A include structural units derived from (meth)acrylic acid or its derivatives (meth)acrylic monomers, as well as those that can be copolymerized with (meth)acrylic monomers.
• a structural unit derived from a monomer having a polymerizable double bond may be included.
• the (meth)acrylic polymer A is not particularly limited as long as it is polymerized using a (meth)acrylic monomer as a basic unit, and preferably has a carboxyl group at the terminal and/or side chain. Moreover, the (meth)acrylic polymer A may contain a reactive functional group other than a carboxyl group at the terminal and/or side chain. Such reactive functional groups are not particularly limited, but include, for example, functional groups containing polymerizable double bonds such as hydroxyl groups, epoxy groups, vinyl groups, and (meth)acryloyl groups.
• Monomers constituting the structural units of (meth)acrylic polymer A are not particularly limited, but include, for example, aliphatic group-containing monomers, carboxyl group-containing monomers, acid anhydride monomers, hydroxyl group-containing monomers, and sulfonic acid group-containing monomers. , phosphoric acid group-containing monomers. Among these, aliphatic group-containing monomers and carboxyl group-containing monomers are more preferred.
• the aliphatic group-containing monomer is not particularly limited, but includes, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, amyl group, isoamyl group, and hexyl group.
• heptyl group cyclohexyl group, 2-ethylhexyl group, octyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, lauryl group, tridecyl group, tetradecyl group, stearyl group, octadecyl group, and dodecyl group
• alkyl (meth)acrylates having a straight chain or branched alkyl group such as a group. These aliphatic group-containing monomers may be used alone or in combination of two or more.
• the structural unit contained in the aliphatic group-containing monomer is preferably 55 to 95 parts by weight, more preferably 65 to 90 parts by weight, even more preferably 75 to 90 parts by weight, based on the total amount of (meth)acrylic polymer A. It is 85 parts by weight.
• carboxyl group-containing monomers examples include, but are not limited to, acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. . These carboxyl group-containing monomers may be used alone or in combination of two or more.
• the structural unit contained in the carboxyl group-containing monomer is preferably 5 to 45 parts by weight, more preferably 10 to 35 parts by weight, even more preferably 15 to 25 parts by weight, based on the total amount of (meth)acrylic polymer A. Parts by weight.
• the acid anhydride monomer is not particularly limited, and examples thereof include maleic anhydride and itaconic anhydride. These acid anhydride monomers may be used alone or in combination of two or more.
• Hydroxyl group-containing monomers are not particularly limited, but examples include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxy(meth)acrylate. - Hydroxyhexyl, 8-hydroxyoctyl (meth)acrylate, 1-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl (meth)acrylate. It will be done. These hydroxyl group-containing monomers may be used alone or in combination of two or more.
• sulfonic acid group-containing monomer examples include, but are not limited to, styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, and sulfopropyl (meth) Examples include acrylate, (meth)acryloyloxynaphthalene sulfonic acid, and the like. These sulfonic acid group-containing monomers may be used alone or in combination of two or more.
• the phosphoric acid group-containing monomer is not particularly limited, but includes, for example, 2-hydroxyethyl acryloyl phosphate.
• the (meth)acrylic polymer A preferably has a polymerizable double bond at the terminal and/or side chain, and is represented by the following formula (1) as a structural unit with a polymerizable double bond introduced into the side chain. It is more preferable to have the structural unit.
• the polymerization initiator can proceed with the polymerization reaction of the (meth)acrylic polymer A by ultraviolet irradiation.
• the adhesive force after irradiation with ultraviolet rays decreases, and contamination of the adherend tends to be further reduced.
• R 1 represents an organic group having a polymerizable double bond
• R 2 represents a single bond or an organic group having 1 to 6 carbon atoms
• R 3 represents a hydrogen atom or a methyl group.
• the organic group having 1 to 6 carbon atoms represented by R 2 is not particularly limited, and examples thereof include linear, branched, or cyclic alkyl groups, alkyleneoxy groups, and the like.
• R 2 is a single bond
• examples of the case where R 2 is a single bond include a structural unit in which an epoxy compound having a polymerizable double bond is added to a structural unit derived from acrylic acid or methacrylic acid.
• the (meth)acrylic polymer A In order to have a polymerizable double bond in the side chain of the (meth)acrylic polymer A, like the structural unit represented by formula (1), the (meth)acrylic polymer A must be ) Polymerization of the carboxyl group of the structural unit derived from the carboxyl group-containing monomer, the anhydrous carboxyl group of the structural unit derived from the acid anhydride monomer, or the hydroxyl group of the structural unit derived from the hydroxyl group-containing monomer, which the acrylic polymer A has. Examples include a method of reacting a denaturing agent having a double bond.
• the polymerizable double bond can be bonded to the structural unit derived from the carboxyl group-containing monomer through an ester bond. can be introduced.
• an isocyanate compound having a polymerizable double bond as a modifier to (meth)acrylic polymer A, a structural unit derived from a carboxyl group-containing monomer is modified through an amide bond. Polymerizable double bonds can be introduced.
• the modifier is not particularly limited as long as it has a functional group that reacts with the functional group of the (meth)acrylic polymer A and has a polymerizable double bond. and isocyanate compounds having a polymerizable double bond.
• the content of the structural unit into which a polymerizable double bond as represented by formula (1) is introduced is preferably 2.5 to 25% by mass based on the total amount of (meth)acrylic polymer A, The content is more preferably 5.0 to 20% by weight, and even more preferably 7.5 to 15% by weight.
• the adhesive strength after ultraviolet irradiation is further reduced, and the polymerizable double bond of (meth)acrylic polymer A is reduced by ultraviolet irradiation.
• the crosslinking reaction of the heavy bonds sufficiently progresses and the contact area with the adherend decreases due to curing shrinkage, the adhesive strength tends to decrease sufficiently. This allows for easy peeling, which tends to further improve pickup performance.
• unpolymerized monomers remain in the adhesive layer, there is a possibility that they can react with the double bonds of (meth)acrylic polymer A during UV irradiation, which tends to further suppress adhesive residue. It is in.
• the decrease in adhesive strength tends to be further suppressed even when stored in a high temperature environment for a long period of time.
• the content of the structural unit into which a polymerizable double bond is introduced is 25% by mass or less, the number of carboxyl groups increases relatively, so the adhesive strength before UV irradiation tends to be further improved.
• the (meth)acrylic polymer A contains a polymerizable double bond.
• the double bond equivalent of (meth)acrylic polymer A is preferably 500 to 2,500 g/mol, more preferably 800 to 2,000 g/mol, and still more preferably 1,000 to 1,800 g/mol.
• the double bond equivalent of the (meth)acrylic polymer A is 500 g/mol or more, the number of carboxyl groups increases relatively, so the adhesive strength before UV irradiation tends to be further improved.
• the double bond equivalent of (meth)acrylic polymer A is 2500 g/mol or less, the crosslinking reaction of the polymerizable double bonds of (meth)acrylic polymer A sufficiently progresses due to ultraviolet irradiation, resulting in curing. As the contact area with the adherend decreases due to shrinkage, the adhesive strength tends to decrease sufficiently. This allows for easy peeling, which tends to further improve pickup performance. Furthermore, even if unpolymerized monomers remain in the adhesive layer, there is a possibility that they can react with the double bonds of (meth)acrylic polymer A during UV irradiation, which tends to further suppress adhesive residue. It is in. Furthermore, since the number of carboxyl groups is relatively reduced, the decrease in adhesive strength tends to be further suppressed even when stored in a high temperature environment for a long period of time.
• double bond equivalent is based on "Testing methods for acid value, saponification value, ester value, iodine value, hydroxyl value, and unsaponifiable substances of chemical products" (JIS K 0070). , the amount of double bonds was determined by measuring the iodine value. Specifically, an iodine monochloride solution was added to the sample to add it to the double bond, and excess I was titrated with a sodium thiosulfate solution to determine it using the following formula.
• A ⁇ (B-C) ⁇ f ⁇ 1.269 ⁇ /S
• the weight average molecular weight of the (meth)acrylic polymer A is preferably 1.0 ⁇ 10 5 to 2.0 ⁇ 10 6 , more preferably 2.0 ⁇ 10 5 to 1.0 ⁇ 10 6 , more preferably 2.5 ⁇ 10 5 to 8.0 ⁇ 10 5 .
• the weight average molecular weight of the (meth)acrylic polymer A By setting the weight average molecular weight of the (meth)acrylic polymer A to 1.0 ⁇ 10 5 or more, the amount of high molecular weight components increases. ) Since there are more opportunities for polymerization with acrylic polymer A through polymerizable double bonds, contamination tends to be further reduced.
• the weight average molecular weight of the (meth)acrylic polymer A is 2.0 ⁇ 10 6 or less, the (meth)acrylic polymer A can move easily, and one (meth)acrylic polymer A can be attached to another (meth)acrylic polymer A. Since there are more opportunities for polymerization with acrylic polymer A, contamination tends to be further reduced. Furthermore, the lower the molecular weight, the lower the elastic modulus of the adhesive, which tends to improve the adhesive strength. In addition, since the followability to the adherend is improved and the step of the adherend can be followed, contamination due to poor UV curing caused by oxygen inhibition can be avoided. Furthermore, since a soft adhesive is easily cured and shrunk by ultraviolet irradiation, the adhesive force after curing can be sufficiently lowered, and the pick-up property tends to be further improved.
• the "weight average molecular weight” described in this specification is the molecular weight measured from a standard polystyrene equivalent molecular weight calibration curve using a gel permeation chromatography analyzer for a sample of (meth)acrylic polymer A dissolved in tetrahydrofuran. It is.
• the glass transition point of the (meth)acrylic polymer A is preferably -80 to 23°C, more preferably -70 to 10°C, even more preferably -60 to 0°C.
• the glass transition point of (meth)acrylic polymer A can be measured by differential scanning calorimetry (DSC method) based on JIS K7121.
• UV ultraviolet rays
• a photopolymerization initiator When using UV as the active energy ray, a photopolymerization initiator is used to harden the adhesive layer and make it easier to peel off the adherend. Any photopolymerization initiator can be used as long as it generates radicals upon UV irradiation and initiates polymerization of the (meth)acrylic polymer.
• photopolymerization initiators are not particularly limited, but include, for example, alkylphenone photopolymerization initiators, alkylphenone photopolymerization initiators, acylphosphine oxide photopolymerization initiators, thioxanthone photopolymerization initiators, and aromatic photopolymerization initiators.
• ketones aromatic onium salt compounds, organic peroxides, thio compounds (thiophenyl group-containing compounds, etc.), ⁇ -aminoalkylphenone compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocenes compounds, active ester compounds, compounds having a carbon-halogen bond, and alkylamine compounds.
• alkylphenone photopolymerization initiators such as acetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexylphenyl ketone, and 2,2-dimethoxy-2-phenylacetophenone are preferred.
• acetophenone acetophenone benzyl ketal, 1-hydroxycyclohexylphenyl ketone, and 2,2-dimethoxy-2-phenylacetophenone
• polymerization tends to proceed more appropriately.
• the content of the photopolymerization initiator is preferably 0.5 to 10 parts by weight, more preferably 0.5 to 7.5 parts by weight, based on 100 parts by weight of (meth)acrylic polymer A. More preferably, it is 0.5 to 5.0 parts by weight.
• the content of the photopolymerization initiator is 0.5 parts by weight or more, the adhesive layer tends to be able to be sufficiently cured even when the illuminance or irradiation amount of ultraviolet rays is low.
• the content of the photopolymerization initiator is 10 parts by weight or less, the risk that the photopolymerization initiator causes contamination tends to decrease.
• the adhesive layer may contain an isocyanate compound. This tends to further improve the cohesive force of the adhesive layer.
• the number of isocyanate groups per molecule of the isocyanate compound is preferably 2 to 6, more preferably 2 to 4.
• the plurality of (meth)acrylic polymers A can also be crosslinked by the isocyanate compound, so that the cohesive force of the adhesive layer tends to be further improved. Furthermore, the anchoring properties between the base material and the adhesive layer are improved, and more stable adhesive properties tend to be obtained.
• Such isocyanate compounds are not particularly limited, but include, for example, aromatic diisocyanates such as trimethylolpropane-modified tolylene diisocyanate, tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, and xylylene diisocyanate; isophorone diisocyanate, methylene bis(4- Examples include alicyclic diisocyanates such as cyclohexyl isocyanate; aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate.
• aromatic diisocyanates such as trimethylolpropane-modified tolylene diisocyanate, tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, and xylylene diisocyanate
• isophorone diisocyanate methylene bis(4- Examples include alicyclic diisocyanates such as
• trimethylolpropane-modified tolylene diisocyanate is more preferred.
• the cohesive force of the adhesive layer tends to be further improved.
• the curing agent is preferably a polyfunctional isocyanate compound having two or more functionalities.
• the plurality of polymers A can also be crosslinked by the curing agent, so that the cohesive force of the adhesive layer tends to be further improved. Furthermore, the anchoring properties between the base material layer and the adhesive layer are improved, and more stable adhesive properties tend to be obtained.
• the content of the isocyanate compound is preferably 3.0 parts by weight or less, more preferably 0.05 to 2.0 parts by weight, and even more preferably The amount is 0.1 to 1.5 parts by weight.
• the content of the isocyanate compound is 0.1 part by weight or more, the crosslinking density of the adhesive layer is further improved, cohesive failure that occurs during peeling is further suppressed, and contamination caused by cohesive failure tends to be further suppressed. be.
• the content of the isocyanate compound is 3.0 parts by weight or less, the crosslinking density is lowered and the elastic modulus is lowered, so that the adhesive strength tends to be further improved.
• the adhesive layer may further contain an amine compound.
• an amine compound By containing an amine compound, it can suppress reactions such as oxidation, esterification, and condensation of the carboxyl group by coordinating with the carboxyl group derived from the (meth)acrylic polymer A, thereby reducing adhesion over time. There is a tendency for sexual decline to be suppressed.
• the amine group possessed by the amine compound is preferably secondary or higher, more preferably secondary to tertiary.
• the amine group in the amine compound is easier to coordinate with the carboxyl group in the (meth)acrylic polymer A, compared to the case where only a primary amine compound is used. The effect of suppressing the decrease in adhesive strength is remarkable.
• the amine compound is not particularly limited, and examples include chain amines and cyclic amines. Among these, cyclic amines are preferred. By using such an amine compound, the nitrogen atom in the amine compound becomes easier to coordinate with the carboxyl group of the (meth)acrylic polymer, and the decrease in adhesive strength during high-temperature storage tends to be more suppressed. .
• chain amines include, but are not limited to, dibutylamine, diisobutylamine, dihexylamine, dioctylamine, bis(2-ethylhexyl)amine, diphenylamine, N-methylaniline, N-ethylaniline, tripropylamine, and tripropylamine.
• Examples include butylamine, triisobutylamine, trihexylamine, trioctylamine, and tris(2-ethylhexyl)amine.
• cyclic amines include alicyclic amines and aromatic amines.
• Alicyclic amines are not particularly limited, but include, for example, pyrrolidine, piperidine, morpholine, imidazoline; piperazine, homopiperazine, 1-methylpiperazine, 2-methylpiperazine, 1-ethylpiperazine, 1,4-dimethylpiperazine, 1
• Piperazine compounds such as -(2-aminoethyl)piperazine; tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)butane-1,2,3,4-tetracarboxylate, tetrakis(2, 2,6,6-tetramethyl-4-piperidyl)butane-1,2,3,4-tetracarboxylate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacic acid, bis( 2,2,6,6-tetramethyl-4-piperidyl) sebacic acid, 1,2,
• aromatic amines include, but are not particularly limited to, pyrrole, pyridine, pyrimidine, pyrazine; imidazole, 2-methylimidazole, 2-undecylimidazole, 2-heptadecyl imidazole, 1,2-dimethylimidazole, -ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2, Imidazole compounds such as 3-dihydro-1H-pyrrolo[1,
• alicyclic amines are preferred, piperidyl compounds and 1,4-diazabicyclo[2,2,2]octane compounds are more preferred, and 1,4-diazabicyclo[2,2,2]octane or derivatives thereof. are more preferred, and compounds having a hydroxyl group such as 1,4-diazabicyclo[2,2,2]octane-2-methanol are particularly preferred.
• 1,4-diazabicyclo[2,2,2]octane-2-methanol are particularly preferred.
• the nitrogen atom extends to the outside of the amine compound, the coordination ability with respect to the carboxyl group is further improved. Therefore, by using such an amine compound, the decrease in adhesive strength during high temperature storage tends to be suppressed. Further, by having a hydroxyl group or the like, compatibility with other components tends to be further improved.
• the term "derivative” refers to a compound in which a hydrogen atom of a compound is substituted with a substituent.
• substituent include, but are not limited to, a halogen group, a hydroxyl group, an amino group, a nitro group, and a carboxyl group.
• the number of amino groups that the amine compound has is preferably 1 to 4, more preferably 1 to 3, and still more preferably 1 to 2.
• the content of the amine compound is 0.1 parts by weight or more, preferably 0.1 to 15 parts by weight, more preferably 0.5 to 15 parts by weight, based on 100 parts by weight of the (meth)acrylic polymer A. 0 parts by weight, more preferably 0.5 to 10.0 parts by weight, even more preferably 0.5 to 5.0 parts by weight.
• the content of the amine compound is 0.1 parts by weight or more, the coordination effect of the amine compound to the carboxyl group of the (meth)acrylic polymer A is sufficiently exhibited, and the decrease in adhesive strength during high-temperature storage is further suppressed. be done.
• the content of the amine compound is 15 parts by weight or less, the adhesive strength before irradiation with ultraviolet rays is further improved, and contamination of the adherend by the amine compound tends to be further suppressed.
• the adhesive layer may contain a (meth)acrylic oligomer.
• the amount of (meth)acrylic oligomer added is not particularly limited, but in order to reduce the risk of contamination due to unreacted oligomer after peeling off the adherend, it is 50 parts by weight per 100 parts by weight of (meth)acrylic polymer A. The following is preferable. This tends to further accelerate the reduction in peeling force after UV exposure.
• the adhesive layer may contain tackifiers, crosslinking retarders, antioxidants, metal trapping agents, ultraviolet absorbers, plasticizers, metal powders, fillers, colorants, (meth)acrylic oligomers, etc. as necessary. Additives may also be added.
• the tackifier is not particularly limited, but includes, for example, petroleum resin, terpene resin, terpene phenol resin, aromatic modified terpene resin, coumaron-indene resin, natural resin rosin, modified rosin, glycerin ester rosin, pentaerythritol ester rosin. , phenol resin, xylene resin, alicyclic petroleum resin, styrene resin, dicyclopentadiene resin and the like.
• crosslinking retarders include, but are not limited to, ⁇ -diketones such as acetylacetone, hexane-2,4-dione, heptane-2,4-dione, and octane-2,4-dione; methyl acetoacetate, acetoacetate, and the like;
• ⁇ -diketones such as acetylacetone, hexane-2,4-dione, heptane-2,4-dione, and octane-2,4-dione
• examples include ⁇ -ketoesters such as ethyl acetate, propyl acetoacetate, butyl acetoacetate, octyl acetoacetate, oleyl acetoacetate, lauryl acetoacetate, and stearyl acetoacetate; benzoylacetone and the like
• Antioxidants include, but are not particularly limited to, methylhydroquinone, hydroquinone, 2,2-methylene-bis(4-methyl-6-tert-butylphenol), catechol, hydroquinone monomethyl ether, monotert-butylhydroquinone, , 5-ditertiarybutylhydroquinone, p-benzoquinone, 2,5-diphenyl-p-benzoquinone, 2,5-ditertiarybutyl-p-benzoquinone, picric acid, citric acid, phenothiazine, tert-butylcatechol, 2-butyl -4-hydroxyanisole, 2,6-ditertiarybutyl-p-cresol and 4-[[4,6-bis(octylthio)-1,3,5-triazin-2-yl]amino]-2,6- Ditertiary butylphenol is mentioned.
• the adhesive tape of this embodiment may have other layers as long as it has a structure in which a base layer, a protective layer, and an adhesive layer are laminated in this order.
• an antistatic layer or the like may be provided on one side or the other side of the base layer.
• the adhesive tape of this embodiment may have a protective film bonded to the adhesive layer in order to protect the adhesive layer. Since the protective film is peeled off when the adhesive tape is used, it is preferable that the protective film has excellent releasability.
• the protective film is not particularly limited, but includes, for example, a film with low surface energy made of a fluororesin, a film whose surface is treated with a silicone release agent of polyethylene terephthalate, and the like.
• the adhesive tape of this embodiment can be suitably used for processing semiconductor wafers, semiconductor devices, or various semiconductor packages.
• the semiconductor wafer may be an individual piece on which an electronic circuit or the like is formed.
• a semiconductor device refers to various types of semiconductor adherends or elements containing them after being separated into individual pieces
• a semiconductor package refers to a semiconductor adherend, a resin for protecting it, a semiconductor adherend, and an external device.
• Method for manufacturing an adhesive tape is not particularly limited, but includes a method of forming an adhesive layer on a base material.
• the base material of the adhesive tape of this embodiment can be manufactured according to well-known techniques.
• the means for forming the base material is not particularly limited, but the various materials mentioned above may be melt-kneaded using conventional methods or various mixing devices (single-screw or twin-screw extruders, rolls, Banbury mixers, various kneaders, etc.).
• the components are mixed so as to be uniformly dispersed, and the mixture is formed into a base material by a T-die method, a calendar method, or an inflation method.
• a method of forming a film using a T-die method using an extruder with good thickness accuracy is preferred.
• the protective layer of the adhesive tape of this embodiment can be manufactured according to well-known techniques.
• the method of forming the adhesive layer is not particularly limited, but the above-mentioned various materials are dissolved in a solvent such as an organic solvent to form a varnish, and this is coated on the protective film using a knife coating method, a roll coating method, or a spray coating method.
• the adhesive layer is formed by applying the adhesive layer by a coating method, a gravure coating method, a bar coating method, a curtain coating method, or the like, and removing the solvent.
• An adhesive tape is produced by laminating this onto a base material.
• the adhesive layer of the adhesive tape of this embodiment can be manufactured according to well-known techniques.
• the method of forming the adhesive layer is not particularly limited, but the above-mentioned various materials are dissolved in a solvent such as an organic solvent to form a varnish, and this is coated on the protective film using a knife coating method, a roll coating method, or a spray coating method.
• the adhesive layer is formed by applying the adhesive layer by a coating method, a gravure coating method, a bar coating method, a curtain coating method, or the like, and removing the solvent.
• An adhesive tape is produced by laminating this onto a base material.
• an aging treatment may be performed after forming the adhesive layer.
• the formed adhesive layer is stored at a predetermined temperature. Temperature conditions are not particularly limited, but are preferably 30 to 50°C, more preferably 35 to 45°C. Further, the storage time is not particularly limited, but is preferably 24 to 150 hours, more preferably 48 to 100 hours. By performing this aging treatment, the adhesive strength and curing characteristics of the adhesive layer change.
• the processing method of the present embodiment includes a bonding step of bonding the above-mentioned adhesive tape and an adherend, and a dicing step of processing the adherend in a state where the adhesive tape and the adherend are bonded together.
• the adherend is a semiconductor wafer, a semiconductor device, or various semiconductor packages.
• the processing method of the present embodiment may include an ultraviolet irradiation step of irradiating the adhesive tape with ultraviolet rays after the dicing step, or separate chips from the adhesive tape after the ultraviolet irradiation. It may include a pickup step of picking up.
• the bonding step is not particularly limited as long as it is a step of bonding the adhesive layer of the pressure-sensitive adhesive tape and the adherend.
• the bonding step may be carried out at room temperature and pressure, or may be carried out under heating or reduced pressure, if necessary.
• the method of dividing into pieces by the dicing process is not particularly limited, and conventionally known methods can be used.
• a silicon wafer can be cut into semiconductor chips by using a dicing device and rotating a dicing blade containing diamond abrasive grains at high speed.
• the ultraviolet irradiation method is not particularly limited, but conventionally known methods can be used.
• an ultraviolet ray irradiation device is used to irradiate the adhesive tape in the dicing process with ultraviolet rays.
• the pickup method is not particularly limited, but a conventionally known method can be used.
• an expanding device can be used to stretch the adhesive tape after irradiation with ultraviolet rays in the surface direction, and each chip can be separated and picked up by a pickup device.
• Example 1 (Preparation of coating solution 1) 80 parts by weight of ethyl acrylate, 20 parts by weight of methyl methacrylate, and 0.05 parts by weight of an initiator (azobisisobutyronitrile) were copolymerized in ethyl acetate at 65°C for 24 hours, An ethyl acrylate-methyl methacrylate copolymer was obtained. Furthermore, the obtained ethyl acrylate-methyl methacrylate copolymer and polyolefin were mixed to obtain coating solution 1 (acid value: 0 mg/KOH).
• an initiator azobisisobutyronitrile
• This coating solution 1 was applied onto the corona-treated surface of an ionomer film (base resin film, manufactured by Gunze Co., Ltd., product name HMD-150, thickness 150 ⁇ m) so that the thickness of the adhesive layer after drying was 1 ⁇ m.
• the protective layer (acid value: 0 mg/KOH) was formed to a thickness of 1 ⁇ m by coating and drying at 100° C. for 1 minute.
• (adhesive layer) 82 parts by weight of 2-ethylhexyl acrylate, 18 parts by weight of acrylic acid, and 0.05 parts by weight of an initiator (azobisisobutyronitrile) were copolymerized in ethyl acetate at 65°C for 24 hours. , a solution containing 0 acrylic polymer was obtained.
• an initiator azobisisobutyronitrile
• an isocyanate compound (trimethylolpropane-modified tolylene diisocyanate, manufactured by Tosoh Corporation: Coronate L-45E) was added to a solution containing 50 parts by weight of acrylic polymer 1 and 50 parts by weight of acrylic polymer 2, and light was added.
• a polymerization initiator (2,2-dimethoxy-2-phenylacetophenone, manufactured by AGM: Omnirad 651)
• amine 1 (1,4-diazabicyclo[2,2,2]octane-2-methanol
• RZETA manufactured by Tosoh approximately 33% active ingredient
• This resin composition was applied onto the release-treated surface of the polyethylene terephthalate protective film so that the adhesive layer after drying had a thickness of 10 ⁇ m, and dried at 120° C. for 1 minute. Thereafter, the protective film and the ionomer film were bonded together so that the adhesive layers were in contact with each other. The adhesive tape was then aged for 72 hours in an atmosphere of 40°C to obtain an adhesive tape.
• Coating solution 2 was obtained by mixing ethyl acrylate-methyl methacrylate copolymer (Colcoat NR-121X-9, manufactured by Colcoat, containing 90 parts by weight of solvent). An adhesive tape was produced in the same manner as in Example 1, except that coating solution 2 was used instead of coating solution 1 to form a protective layer (acid value: 0 mg/KOH).
• Example 3 10 parts by weight of maleic anhydride-modified hydrogenated styrene-butadiene-styrene block copolymer (manufactured by Asahi Kasei: Tuftec M1913, acid value 0 mgKOH/g) and 90 parts by weight of toluene (solvent) were mixed to prepare coating solution 3 ( An acid value of 0 mg/KOH) was obtained.
• An adhesive tape was produced in the same manner as in Example 1, except that coating solution 3 was used instead of coating solution 1 to form a protective layer (acid value: 0 mg/KOH).
• Example 4 An adhesive tape was produced in the same manner as in Example 1, except that in forming the adhesive layer, the amount of acrylic polymer 1 used was 100 parts by weight, and the amount of acrylic polymer 2 was 0 parts by weight.
• Example 5 An adhesive tape was produced in the same manner as in Example 1, except that in forming the adhesive layer, the amount of acrylic polymer 1 used was 0 parts by weight, and the amount of acrylic polymer 2 used was 100 parts by weight.
• Example 6 Acrylic acid-2-ethylhexy-acrylic acid copolymer (manufactured by Negami Kogyo: DT-7-0, acid value 0 mgKOH/g, glass transition temperature 7°C, weight average molecular weight 450,000) 24.0 parts by weight (mixed solvent propyl acetate) 13.2 parts by weight) and 76.0 parts by weight toluene (solvent) were mixed to obtain coating solution 4 (acid value 92 mg/KOH).
• An adhesive tape was produced in the same manner as in Example 1, except that coating solution 4 was used instead of coating solution 1 to form a protective layer (acid value: 92 mg/KOH).
• Example 7 In forming the adhesive layer, the amount of acrylic polymer 1 used was 0 parts by weight, the amount of acrylic polymer 2 used was 90 parts by weight, and 10 parts by weight of acrylic polymer 4 (polyacrylic acid, acid value 779 mgKOH/g) was used.
• An adhesive tape was produced in the same manner as in Example 1, except that the adhesive layer was obtained using the following methods.
• Example 8 An adhesive tape was produced in the same manner as in Example 1, except that 1,4-diazabicyclo[2,2,2]octane-2-methanol was not used in forming the adhesive layer.
• Example 9 (Synthesis of acrylic polymer 5) First, side chain double bond-introduced acrylic polymer 5 was prepared by reacting glycidyl methacrylate with the carboxyl group of the acrylic acid unit in acrylic polymer 0 obtained in the same manner as in Example 1 to introduce a double bond into the side chain. (Acid value: 18 mg/KOH) was obtained. At this time, the two were reacted so that the amount of glycidyl methacrylate introduced was 80 mol (80 mol %) per 100 mol of methacrylic acid units of the acrylic polymer.
• the amount of acrylic polymer 1 used was 0 parts by weight
• the amount of acrylic polymer 2 used was 0 parts by weight
• the adhesive layer was obtained using 100 parts by weight of acrylic polymer 5.
• An adhesive tape was produced in the same manner as in Example 1.
• the amount of acrylic polymers 1 and 2 used was 0 parts by weight, and the amount of acrylic polymer 3 (manufactured by Mitsubishi Chemical Corporation, product name N-2993, acid value 0 mgKOH/g) was 100 parts by weight.
• An adhesive tape was produced in the same manner as in Example 1, except that the amount of acrylic oligomer 1 (manufactured by Negami Kogyo Co., Ltd., product name UN-904M, acid value 0 mgKOH/g) was 30 parts by weight.
• the acid value [mgKOH/g] of the protective layer and adhesive layer included in the adhesive tape of each example and each comparative example was determined by first weighing 1 g of the resin composition for forming the protective layer or adhesive layer, and The composition was dissolved in 30 g of tetrahydrofuran (THF) in a conical beaker, after which a few drops of phenolphthalein were added. Then, the neutralization point was calculated by dropping a 0.1N KOH solution (solvent: 2-propanol (IPA)) from a burette in an environment of 23°C.
• solvent solvent: 2-propanol (IPA)
• Adhesion strength to silicon wafer 180° peel strength>
• the adhesive strength of the adhesive tape was measured in accordance with the adhesive strength measurement method of JIS Z0237 (2009) (Method 1: test method in which the tape and sheet are peeled off at 180° with respect to a stainless steel test plate). Specifically, the protective film was peeled off, and the adhesive layer of the adhesive tape was pressed onto the silicon wafer whose surface had been cleaned using a pressure bonding device (roller mass: 2 kg), and the adhesive tape was applied at 180 degrees to the silicon wafer.
• the 180° peel strength S 0 when peeled off was measured using a universal tensile tester (Tensilon model number: RTG-1210, manufactured by ORIENTEC) in an environment of a temperature of 23° C. and a humidity of 50%. Peel strength S 0 means adhesive strength to a silicon wafer before UV irradiation.
• peel strength S1 means adhesive strength to a silicon wafer after UV irradiation.
• peel strength S 0 and S 1 The measurement conditions and evaluation criteria for peel strength S 0 and S 1 are shown below.
• Measurement condition Measurement mode: tension
• Tensile speed 300mm/min Distance between chucks: 50mm
• Measurement sample width 20mm
• evaluation criteria for peel strength S0 A: Peel strength S 0 is 6.0 N/20 mm or more
• Peel strength S 0 is less than 4.0 N/20 mm
• peel strength S 1 A: Peel strength S 1 is less than 0.30 N/20 mm
• B: Peel strength S 1 is 0.30 N/20 mm or more and less than 0.50 N/20 mm
• Peel strength S 1 is 0.50 N/20 mm or more
• the adhesive tape was stored in a constant temperature machine at 40°C for one month, and then stored in an atmosphere of 23°C and 50% RH for more than 2 hours to adjust the tape temperature to 23°C.
• Using the adhesive tape remove the protective film and press the adhesive layer of the adhesive tape onto the silicon wafer whose surface has been cleaned using a pressure bonding device (roller mass 2 kg) in the same manner as above.
• the 180° peel strength S0 ' when the adhesive tape is peeled off at 180° using a universal tensile tester (Tensilon model number: RTG-1210 manufactured by ORIENTEC) in an environment of 23°C and 50% humidity is measured. did.
• Ratio (S 0 '/S 0 ) is 0.90 or more
• B Ratio (S 0 '/S 0 ) is 0.80 or more and less than 0.90
• Ratio (S 0 '/S 0 ) is , less than 0.80
• the adhesive tape of the present invention has industrial applicability as a tape for semiconductor wafer processing, particularly as an adhesive tape used in a dicing process.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Condensed Matter Physics & Semiconductors (AREA)
• General Physics & Mathematics (AREA)
• Manufacturing & Machinery (AREA)
• Computer Hardware Design (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Power Engineering (AREA)
• Adhesive Tapes (AREA)
• Adhesives Or Adhesive Processes (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=88200705

Family Applications (1)

Country Status (3)

Citations (9)

• 2023
  • 2023-01-19 JP JP2024511281A patent/JPWO2023188714A1/ja active Pending
  • 2023-01-19 WO PCT/JP2023/001444 patent/WO2023188714A1/ja active Application Filing
  • 2023-03-22 TW TW112110638A patent/TW202346388A/zh unknown

Patent Citations (9)

Also Published As

Similar Documents

Legal Events