WO2019155970A1 - Adhesive tape for semiconductor fabrication - Google Patents

Adhesive tape for semiconductor fabrication Download PDF

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Publication number
WO2019155970A1
WO2019155970A1 PCT/JP2019/003246 JP2019003246W WO2019155970A1 WO 2019155970 A1 WO2019155970 A1 WO 2019155970A1 JP 2019003246 W JP2019003246 W JP 2019003246W WO 2019155970 A1 WO2019155970 A1 WO 2019155970A1
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WO
WIPO (PCT)
Prior art keywords
adhesive layer
pressure
sensitive adhesive
adhesive tape
tape
Prior art date
Application number
PCT/JP2019/003246
Other languages
French (fr)
Japanese (ja)
Inventor
裕也 長谷川
Original Assignee
リンテック株式会社
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Publication date
Application filed by リンテック株式会社 filed Critical リンテック株式会社
Priority to JP2019570712A priority Critical patent/JP7404073B2/en
Priority to KR1020207019966A priority patent/KR102642079B1/en
Publication of WO2019155970A1 publication Critical patent/WO2019155970A1/en

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    • 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
    • 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
    • C09J201/00—Adhesives based on unspecified macromolecular compounds
    • 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
    • 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 at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System 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
    • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H01L21/304—Mechanical treatment, e.g. grinding, polishing, cutting
    • 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
    • C09J2203/00—Applications of adhesives in processes or use of adhesives in the form of films or foils
    • C09J2203/326—Applications of adhesives in processes or use of adhesives in the form of films or foils for bonding electronic components such as wafers, chips or semiconductors
    • 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
    • C09J2301/00—Additional features of adhesives in the form of films or foils
    • C09J2301/30—Additional features of adhesives in the form of films or foils characterized by the chemical, physicochemical or physical properties of the adhesive or the carrier
    • C09J2301/312—Additional features of adhesives in the form of films or foils characterized by the chemical, physicochemical or physical properties of the adhesive or the carrier parameters being the characterizing feature

Definitions

  • the present invention relates to an adhesive tape for semiconductor processing.
  • the present invention relates to an adhesive tape for semiconductor processing that is suitably used for protecting a circuit surface when processing a semiconductor wafer.
  • Semiconductor chips mounted on various electronic devices are obtained by dividing a semiconductor wafer on which a circuit is formed. Electronic devices are rapidly becoming smaller and more multifunctional, and semiconductor chips are also required to be smaller, lower in profile and higher in density. In order to reduce the size and height of a chip, it is common to adjust the thickness of the chip by forming a circuit on the surface of the semiconductor wafer and then grinding the back surface of the semiconductor wafer.
  • an adhesive tape called a back grind tape is attached to the wafer surface in order to protect the circuit on the wafer surface and hold the semiconductor wafer.
  • the semiconductor wafer after the back grinding is transferred to the next process such as a dicing process for separating the wafer into individual pieces.
  • the semiconductor wafer after back grinding is very thin and tends to warp together with the adhesive tape. Further, since the semiconductor wafer is held only by the adhesive tape having low rigidity, the semiconductor wafer is easily loaded and damaged during transportation.
  • the peripheral portion of the back grind tape is also attached to a ring-shaped frame (hereinafter also referred to as a ring frame) that is attached to a grinding device at the time of back surface grinding. It is described that the back surface grinding is performed after being fixed to the ring frame via a grind tape. That is, the metal ring frame, the semiconductor wafer, and the back grind tape are integrated and placed on the chuck table, and the back surface of the semiconductor wafer is ground by the grinder.
  • a ring-shaped frame hereinafter also referred to as a ring frame
  • the semiconductor wafer after the back surface grinding can be transported to the next process together with a highly rigid ring frame. Therefore, even if the semiconductor wafer after grinding is very thin, warpage of the semiconductor wafer is suppressed by the ring frame. Further, since the load is hardly applied to the wafer during transfer, damage to the wafer can be suppressed.
  • the back grind tape is fixed to the ring frame and transported to the next process, if the next process is a dicing process, the back grind tape affixed to the ring frame also serves as the dicing tape Can do.
  • adhesive sheets are collectively referred to as “adhesive tape for semiconductor processing”.
  • the semiconductor wafer is not directly supported by the ring frame, but is attached to the back grind tape, so that the load of the semiconductor wafer is applied to the back grind tape. Since this semiconductor wafer is a wafer before the back surface grinding, it is heavier than the wafer after the back surface grinding. Therefore, there is a problem that the back grind tape is loosened due to the weight of the semiconductor wafer.
  • the present invention has been made in view of such a situation, and an object of the present invention is to provide a pressure-sensitive adhesive tape for semiconductor processing in which the looseness of the pressure-sensitive adhesive tape is suppressed and the peelability from the ring frame is good.
  • aspects of the present invention include [1] An adhesive tape having a substrate and an adhesive layer provided on one surface side of the substrate, Before the energy ray irradiation to the pressure-sensitive adhesive layer, the gel fraction of the pressure-sensitive adhesive layer is 35% or more, and the loss tangent of the pressure-sensitive adhesive layer at 50 ° C. is less than 0.65, The adhesive tape for semiconductor processing, wherein the adhesive force of the adhesive layer is 3100 mN / 25 mm or less after energy beam irradiation to the adhesive layer.
  • an adhesive tape for semiconductor processing in which the looseness of the adhesive tape is suppressed and the peelability from the ring frame is good.
  • FIG. 1 is a cross-sectional view of an adhesive tape for semiconductor processing according to an embodiment of the present invention.
  • FIG. 2A is a schematic cross-sectional view for explaining a method for manufacturing a semiconductor device using an adhesive tape for semiconductor processing according to an embodiment of the present invention.
  • FIG. 2B is a continuation of FIG. 2A.
  • FIG. 2C is a continuation of FIG. 2B.
  • FIG. 2D is a continuation of FIG. 2C.
  • FIG. 2E is a continuation of FIG. 2D.
  • FIG. 2F is a continuation of FIG. 2E.
  • the adhesive tape 1 for semiconductor processing has a configuration in which an adhesive layer 20 is laminated on a base material 10 as shown in FIG.
  • the pressure-sensitive adhesive tape for semiconductor processing is not limited to the configuration shown in FIG. 1 and may have other layers as long as the effects of the present invention are obtained.
  • a release sheet may be formed on the main surface 20a of the adhesive layer 20.
  • the adherend (the ring frame for fixing the semiconductor wafer and the surface of the semiconductor wafer) is attached to the main surface 20a of the adhesive layer 20 before the semiconductor wafer is processed (for example, back grinding). Then, after processing the semiconductor wafer, the semiconductor processing pressure-sensitive adhesive tape, that is, the pressure-sensitive adhesive layer 20 is peeled from the semiconductor wafer and the ring frame. Therefore, the pressure-sensitive adhesive layer has an adhesive force showing an appropriate removability to both the semiconductor wafer and the ring frame that are adherends.
  • the thickness of the pressure-sensitive adhesive layer 20 is not particularly limited, but is preferably 1 ⁇ m to 50 ⁇ m, more preferably 5 ⁇ m to 30 ⁇ m, and still more preferably 12 ⁇ m to 18 ⁇ m. If the thickness of the pressure-sensitive adhesive layer is too thin, the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer tends to be low during the processing of the semiconductor wafer. On the other hand, if it is too thick, the thickness of the semiconductor wafer tends to vary during backside grinding.
  • the main surface of the adhesive layer to which the ring frame and the semiconductor wafer are attached has the following physical properties.
  • the following physical properties are manifested on the main surface of the pressure-sensitive adhesive layer at least in the region where the ring frame and the semiconductor wafer are attached.
  • the gel fraction of the pressure-sensitive adhesive layer is 35% or more before energy ray irradiation to the pressure-sensitive adhesive layer.
  • the adhesive layer is not easily deformed even when a force is applied to the adhesive layer before the energy ray irradiation, that is, in the step such as back grinding, the gel fraction is within the above range. As a result, tape slack tends to be suppressed.
  • the gel fraction of the pressure-sensitive adhesive layer is preferably 37% or more, and more preferably 40% or more. Moreover, it is preferable that the gel fraction of an adhesive layer is 70% or less, It is more preferable that it is 60% or less, It is further more preferable that it is 50% or less. When the gel fraction is too large, tape slack is sufficiently suppressed, but the tape elongation during back surface grinding becomes small and the grinder tends to come into contact with the ring frame.
  • the loss tangent (tan ⁇ ) of the pressure-sensitive adhesive layer at 50 ° C. is less than 0.65.
  • the loss tangent (tan ⁇ ) is defined as “loss elastic modulus / storage elastic modulus”, and is a value measured by a response to a stress such as a tensile stress or a torsional stress applied to an object by a dynamic viscoelasticity measuring apparatus.
  • the loss tangent of the pressure-sensitive adhesive layer is preferably 0.60 or less, and more preferably 0.55 or less. Further, the loss tangent of the pressure-sensitive adhesive layer is preferably 0.30 or more, and more preferably 0.40 or more. If the loss tangent is too small, the tape slack is sufficiently suppressed, but the tape elongation during back grinding becomes small, and the grinder may come into contact with the ring frame.
  • the pressure-sensitive adhesive strength of the pressure-sensitive adhesive layer is 3100 mN / 25 mm or less.
  • energy beam irradiation that is, when peeling the adhesive tape for semiconductor processing from the ring frame
  • the pressure sensitive adhesive layer should be peeled well not only from the wafer but also from the ring frame because it is within the above range. Can do.
  • the adhesive strength of the pressure-sensitive adhesive layer after irradiation with energy rays is preferably 3000 mN / 25 mm or less, and more preferably 2500 mN / 25 mm or less.
  • the adhesive layer has the physical properties shown in the above (1.1.1.) To (1.1.3.), So that the slack of the adhesive tape is suppressed during back grinding, and it is excellent from the ring frame after back grinding. Can be peeled off.
  • the structure and composition of the pressure-sensitive adhesive layer are not particularly limited as long as the pressure-sensitive adhesive layer has the above physical properties, but in the present embodiment, it is preferable to have the following structure and components.
  • the change in the adhesive force of the adhesive layer before and after energy beam irradiation is used in order to improve the peeling of the adhesive tape from the semiconductor wafer and the ring frame. That is, in processing steps such as back grinding, the adhesive layer is secured to the adhesive tape, the ring frame, and the semiconductor wafer without irradiating the adhesive layer with energy rays.
  • the pressure-sensitive adhesive layer is irradiated with energy rays to reduce the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer, thereby making it easy to peel the pressure-sensitive adhesive tape from the ring frame.
  • the adhesive layer of the adhesive tape for semiconductor processing according to the present embodiment contains an energy ray curable resin as a constituent component.
  • an energy beam curable resin has a relatively low molecular weight and low cohesion. Therefore, when the energy ray curable resin before energy ray irradiation is contained in the pressure-sensitive adhesive layer, the energy ray curable resin easily moves when force is applied to the pressure-sensitive adhesive layer. As a result, the pressure-sensitive adhesive layer is easily deformed, and it becomes difficult to suppress the slack of the tape.
  • a crosslinked structure is introduced in the pressure-sensitive adhesive layer. Due to the presence of the cross-linked structure, the movement of the energy beam curable resin is hindered by the cross-linked structure, and the above-described gel fraction and loss tangent can be easily within the above ranges, and the adhesive strength after irradiation with the energy beam. Can be sufficiently reduced.
  • the cross-linked structure is preferably formed of a functional group-containing acrylic polymer and a cross-linking agent. Therefore, the pressure-sensitive adhesive layer preferably has a functional group-containing acrylic polymer, a crosslinking agent, and an energy ray curable resin. These constituent components will be described in detail.
  • the functional group-containing acrylic polymer may be a known acrylic polymer.
  • the functional group-containing acrylic polymer may be a homopolymer formed from one type of acrylic monomer, or may be a copolymer formed from a plurality of types of acrylic monomers. It may be a copolymer formed from one kind or plural kinds of acrylic monomers and monomers other than acrylic monomers.
  • the functional group-containing acrylic polymer is preferably an acrylic copolymer obtained by copolymerizing an alkyl (meth) acrylate and a functional group-containing monomer.
  • (meth) acrylate is used as a term indicating both “acrylate” and “methacrylate”, and the same applies to other similar terms.
  • alkyl (meth) acrylate examples include an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, preferably an alkyl (meth) acrylate having an alkyl group having 1 to 8 carbon atoms, more preferably a carbon number. Examples thereof include alkyl (meth) acrylates having 1 to 4 alkyl groups.
  • alkyl (meth) acrylate examples include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t- Examples include butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, and n-octyl (meth) acrylate. Of these, butyl acrylate is preferred.
  • alkyl (meth) acrylate In the functional group-containing acrylic copolymer, only one type of alkyl (meth) acrylate may be contained, or two or more types may be contained.
  • the structural unit derived from alkyl (meth) acrylate is preferably 70% by mass or more, and more preferably 80% by mass or more, based on all structural units of the functional group-containing acrylic copolymer.
  • the constituent unit derived from alkyl (meth) acrylate is preferably 99% by mass or less, and more preferably 90% by mass or less.
  • the functional group-containing monomer is a monomer containing a reactive functional group.
  • the reactive functional group is a functional group capable of reacting with other compounds such as a crosslinking agent described later.
  • An acrylic copolymer has a structural unit derived from a functional group-containing monomer, and is crosslinked by a crosslinking agent.
  • the reactive functional group examples include a carboxy group, a hydroxy group, and an epoxy group. In these, since the reactivity with a crosslinking agent is favorable, a carboxy group is more preferable.
  • Examples of functional group-containing monomers include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. Also, hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl ( Examples thereof include hydroxy group-containing (meth) acrylates such as (meth) acrylate and 4-hydroxybutyl (meth) acrylate. Moreover, unsaturated alcohols, such as vinyl alcohol and allyl alcohol, are illustrated.
  • epoxy groups containing glycidyl (meth) acrylate, ⁇ -methylglycidyl (meth) acrylate, (3,4-epoxycyclohexyl) methyl (meth) acrylate, 3-epoxycyclo-2-hydroxypropyl (meth) acrylate and the like examples include (meth) acrylates.
  • Non-acrylic epoxy group-containing monomers such as glycidyl crotonate and allyl glycidyl ether are also exemplified.
  • Only one type of functional group-containing monomer may be included in the acrylic copolymer, or two or more types may be included.
  • ethylenically unsaturated carboxylic acid is preferable, among which acrylic acid and methacrylic acid are more preferable, and acrylic acid is more preferable.
  • the structural unit derived from the functional group-containing monomer is preferably 1% by mass or more, and more preferably 5% by mass or more, in all the structural units of the acrylic copolymer containing the functional group.
  • the constitutional unit derived from the functional group-containing monomer is preferably 30% by mass or less, and more preferably 15% by mass or less.
  • the weight average molecular weight (Mw) of the functional group-containing acrylic polymer is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000 from the viewpoint of film forming properties at the time of coating.
  • the weight average molecular weight in this specification is the value of polystyrene conversion measured by the gel permeation chromatography (GPC) method.
  • the acrylic polymer containing a functional group may contain a constituent monomer other than the alkyl (meth) acrylate and the functional group-containing monomer described above.
  • cycloalkyl (meth) acrylate having about 1 to 20 carbon atoms in the cycloalkyl group
  • benzyl (meth) acrylate isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meta ) (Meth) acrylates having a cyclic skeleton such as acrylate and dicyclopentenyloxyethyl (meth) acrylate
  • acrylamide compounds such as acrylamide, N-methylacrylamide and N, N-dimethylacrylamide
  • vinyl such as vinyl acetate and vinyl propionate Ester compound
  • Olefin such as ethylene, propylene and isobutylene
  • Halogenated olefin such as vinyl chloride and vinylidene chloride
  • the cross-linking agent is not particularly limited as long as the pressure-sensitive adhesive layer can form a cross-linking structure that easily satisfies the above characteristics.
  • a relatively loosely crosslinked structure is mainly formed, and a structure that is partially relatively strongly crosslinked is present in the structure.
  • a part of the structure that is relatively loosely crosslinked has a structure that is relatively strongly crosslinked, so that it is easy to satisfy the physical properties of the pressure-sensitive adhesive layer.
  • crosslinking agents are used as a crosslinking agent for the acrylic copolymer containing a functional group.
  • a polyisocyanate-based crosslinking agent as a crosslinking agent that forms a relatively loosely crosslinked structure
  • an epoxy-based crosslinking agent as a crosslinking agent that forms a relatively strongly crosslinked structure.
  • crosslinking agents react with the functional groups in the functional group-containing acrylic polymer to crosslink the functional group-containing acrylic polymer.
  • the degree of crosslinking differs between the polyisocyanate crosslinking agent and the epoxy crosslinking agent.
  • the polyisocyanate-based crosslinking agent is a compound having two or more isocyanate groups per molecule.
  • Specific examples include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate; alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate. .
  • biuret bodies, isocyanurate bodies, and adduct bodies that are a reaction product of these with low molecular active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, etc.
  • low molecular active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, etc.
  • polyisocyanate type crosslinking agent only 1 type may be contained and 2 or more types may be contained.
  • Examples of the epoxy-based crosslinking agent include 1,3-bis (N, N′-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, and ethylene glycol diglycidyl ether. 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidylaniline, diglycidylamine and the like. As for an epoxy type crosslinking agent, only 1 type may be contained and 2 or more types may be contained.
  • the content of the polyisocyanate-based crosslinking agent is preferably 5 parts by mass or more with respect to 100 parts by mass of the functional group-containing acrylic copolymer. On the other hand, the content is preferably 15 parts by mass or less.
  • the content of the epoxy crosslinking agent is preferably 0.01 parts by mass or more, and more preferably 0.03 parts by mass or more with respect to 100 parts by mass of the functional group-containing acrylic copolymer.
  • the content is preferably 0.5 parts by mass or less, more preferably 0.3 parts by mass or less, and further preferably 0.1 parts by mass or less.
  • the content of the polyisocyanate-based crosslinking agent and the epoxy-based crosslinking agent is within the above range, it becomes easy to adjust the adhesive strength of the semiconductor processing adhesive tape before energy beam irradiation to the semiconductor wafer and the ring frame. Moreover, after the production of the adhesive tape for semiconductor processing, the adhesive property is stabilized without requiring an excessively long curing period.
  • the gel fraction of the crosslinked structure that is, the gel fraction of the crosslinked structure formed from the functional group-containing acrylic polymer and the crosslinking agent is preferably 70% or more and 95% or less.
  • the gel fraction of the pressure-sensitive adhesive layer described above is a gel fraction that takes into consideration not only the crosslinked structure but also the energy ray-curable resin having a relatively low molecular weight. It depends. For example, if a large amount of low molecular weight energy ray curable resin is contained, the gel fraction of the pressure-sensitive adhesive layer tends to be low. On the other hand, since the gel fraction of the crosslinked structure excludes the influence of the energy ray curable resin, it is considered that the degree of crosslinking is more reflected. In this embodiment, it is preferable that the gel fraction of a crosslinked structure is larger than the gel fraction of an adhesive layer.
  • the energy ray curable resin is a resin having an unsaturated group curable by irradiation with energy rays in the molecule.
  • unsaturated groups include (meth) acryloyl groups and vinyl groups.
  • the energy ray curable resin is preferably a low molecular weight compound (monofunctional and polyfunctional monomers and oligomers). Moreover, since said crosslinked structure is formed by thermal crosslinking, in order to ensure the adhesive force before energy beam irradiation, what is hard to carry out thermal crosslinking of energy beam curable resin is preferable.
  • low molecular weight energy ray curable resins examples include trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butylene.
  • Cycloaliphatic skeleton-containing acrylates such as glycol diacrylate, 1,6-hexanediol diacrylate, dicyclopentadiene dimethoxydiacrylate, and isobornyl acrylate; polyethylene glycol diacrylate, oligoester acrylate, urethane acrylate oligomer, epoxy modified Acrylate compounds such as acrylate, polyether acrylate, itaconic acid oligomer Like it is exemplified. These may be one type or two or more types.
  • a polyfunctional monomer or oligomer is more preferable, and a polyfunctional urethane (meth) acrylate oligomer is particularly preferable.
  • the molecular weight (weight average molecular weight in the case of oligomer) of the energy beam curable resin is preferably 500 or more, and more preferably 1000 or more. On the other hand, the molecular weight is preferably 10,000 or less, more preferably 7000 or less, further preferably 5000 or less, and particularly preferably 3000 or less.
  • the molecular weight of the energy ray curable resin is within the above range, it has a predetermined adhesive strength before irradiation with energy rays, and the adhesive strength is reduced to such an extent that it can be peeled off from the ring frame after irradiation with energy rays. It becomes easy to make.
  • the content of the energy ray curable resin is preferably 50 parts by mass or more and more preferably 100 parts by mass or more with respect to 100 parts by mass of the functional group-containing acrylic copolymer. On the other hand, the content is preferably 250 parts by mass or less, and more preferably 200 parts by mass or less.
  • the content of the energy ray curable resin is within the above range, so that it has a predetermined adhesive force before irradiation with energy rays, and has an adhesive force that can be peeled off from the ring frame after irradiation with energy rays. It becomes easy to lower.
  • Examples of energy rays for curing the pressure-sensitive adhesive layer include ultraviolet rays and electron beams. Among these, ultraviolet rays that are relatively easy to introduce irradiation equipment are preferable.
  • near ultraviolet rays including ultraviolet rays having a wavelength of about 200 to 380 nm for ease of handling.
  • the amount of light may be appropriately selected according to the type of energy ray curable group of the pressure-sensitive adhesive layer and the thickness of the pressure-sensitive adhesive tape for semiconductor processing, and is usually about 50 to 500 mJ / cm 2 , and is 100 to 450 mJ / cm 2 is preferable, and 200 to 400 mJ / cm 2 is more preferable.
  • the ultraviolet illumination is usually 50 ⁇ 500mW / cm 2 or so, preferably 100 ⁇ 450mW / cm 2, more preferably 200 ⁇ 400mW / cm 2.
  • the ultraviolet light source is not particularly limited, and for example, a high pressure mercury lamp, a metal halide lamp, a UV-LED, or the like is used.
  • the pressure-sensitive adhesive layer may contain other components such as dyes, pigments, deterioration inhibitors, antistatic agents, flame retardants, silicone compounds, chain transfer agents, plasticizers, and photopolymerization initiators.
  • the pressure-sensitive adhesive layer contains an energy ray curable resin
  • a photopolymerization initiator the curing is sufficiently performed and the adhesive strength after irradiation with the energy ray is lowered to a level that can be satisfactorily peeled from the ring frame. Can do.
  • photopolymerization initiators examples include photoinitiators such as benzoin compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, thioxanthone compounds, and peroxide compounds, and photosensitizers such as amines and quinones.
  • ⁇ -hydroxycyclohexyl phenyl ketone benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, dibenzyl, diacetyl, ⁇ -chlore
  • examples include anthraquinone and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.
  • the base material 10 of the adhesive tape 1 for semiconductor processing according to the present embodiment is particularly preferably formed of a material that extends to such a degree that the grinder and the ring frame do not come into contact with each other and that does not break the adhesive tape when processing a semiconductor wafer. Not limited.
  • ethylene-based copolymer films such as ethylene-vinyl acetate copolymer film, ethylene- (meth) acrylic acid copolymer film, ethylene- (meth) acrylic acid ester copolymer film; low density polyethylene (LDPE) film, polyethylene film such as linear low density polyethylene (LLDPE) film, high density polyethylene (HDPE) film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, ethylene-norbornene copolymer film, norbornene
  • LDPE low density polyethylene
  • HDPE high density polyethylene
  • polypropylene film polybutene film, polybutadiene film, polymethylpentene film, ethylene-norbornene copolymer film, norbornene
  • polyolefin films such as resin films
  • polyvinyl chloride films such as polyvinyl chloride films and vinyl chloride copolymer films
  • polyurethane films and the like are examples of poly
  • modified films such as these crosslinked films and ionomer films can be used.
  • the substrate 10 may be a film made of one of these, or a laminated film in which two or more of these are combined.
  • the surface on which the pressure-sensitive adhesive layer 20 is formed may be subjected to corona treatment or may be provided with a primer layer.
  • the film constituting the substrate 10 is preferably at least one selected from an ethylene copolymer film and a polyolefin film.
  • the thickness of the base material 10 is not limited as long as the adhesive tape 1 for semiconductor processing according to this embodiment exhibits the effects of the present invention.
  • the thickness is preferably 20 ⁇ m or more and 450 ⁇ m or less, more preferably 25 ⁇ m or more and 400 ⁇ m or less, and particularly preferably 50 ⁇ m or more and 350 ⁇ m or less.
  • the method for producing the adhesive tape for semiconductor processing according to the present embodiment is not particularly limited as long as it can form an adhesive layer on one surface of the substrate, and a known method may be used.
  • a composition for forming the pressure-sensitive adhesive layer for example, a pressure-sensitive adhesive composition containing the above-described components (functional group-containing acrylic polymer, crosslinking agent, energy ray curable resin), or the pressure-sensitive adhesive A composition is prepared by diluting the agent composition with a solvent or the like.
  • the solvent examples include organic solvents such as methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, n-propanol, and isopropanol.
  • organic solvents such as methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, n-propanol, and isopropanol.
  • this adhesive composition, etc., on the substrate known methods such as spin coating method, spray coating method, bar coating method, knife coating method, roll coating method, blade coating method, die coating method, gravure coating method, etc. Is applied, heated and dried to form an adhesive layer on the substrate.
  • an adhesive composition or the like is applied to the release treatment surface of the release sheet, heated and dried to form an adhesive layer on the release sheet, and then the adhesive layer and the substrate on the release sheet are formed.
  • the adhesive tape for a semiconductor processing by which the adhesive layer and the peeling sheet were provided in this order on the base material may be manufactured by bonding.
  • drying conditions after coating for example, heating at a temperature of 80 to 150 ° C. for 30 seconds to 5 minutes may be performed.
  • the pressure-sensitive adhesive composition or the like contains a cross-linking agent, a cross-linking reaction is caused by heating. Therefore, in order to sufficiently advance the cross-linking reaction, the drying conditions (temperature, time, etc.) may be changed. A heat treatment may be separately provided.
  • the resulting semiconductor processing pressure-sensitive adhesive tape is cured for about one week in an environment of, for example, 23 ° C. and a relative humidity of 50%.
  • the surface (surface 50a) on which the circuit of the semiconductor wafer 50 is formed and the ring frame 60 are affixed to one main surface of the adhesive layer of the semiconductor processing adhesive tape 1.
  • the semiconductor wafer 50 is fixed to the ring frame 60 via the semiconductor processing adhesive tape 1 while protecting the surface.
  • the semiconductor wafer may be a silicon wafer or a compound semiconductor wafer such as gallium / arsenic. A known method may be adopted as a method for forming the circuit.
  • the thickness of the semiconductor wafer on which the predetermined circuit is formed is not particularly limited, but is usually about 500 to 1000 ⁇ m.
  • the semiconductor wafer is placed on the chuck table of the grinding device, and the ring frame is fixed to the grinding device.
  • the ring frame 60 side is pushed down or the chuck table 75 side is pushed up in order to prevent contact between the grinder 70 and the ring frame 60.
  • the semiconductor processing adhesive tape 1 is stretched, and in this state, the back surface 50 b of the semiconductor wafer 50 is ground by the grinder 70.
  • the back surface grinding is finished, the ring frame 60 side or the chuck table 75 side returns to the original position, and the elongation of the adhesive tape 1 for semiconductor processing is released.
  • the adhesive tape for semiconductor processing is irradiated with energy rays, the adhesive is cured, the adhesive force is reduced, and the adhesive tape for semiconductor processing may be peeled off from the circuit surface.
  • the semiconductor processing pressure-sensitive adhesive tape is conveyed to the dicing process in a state where the adhesive tape is attached to the ring frame and the semiconductor wafer. That is, the semiconductor processing adhesive tape serves not only as a back grind tape but also as a dicing tape.
  • the semiconductor wafer is divided into a plurality of semiconductor chips.
  • a known method can be adopted as a method of dividing into individual pieces. For example, as shown in FIG. 2C, by using a rotary blade 80 such as a dicer to form a groove penetrating the front and back surfaces of the semiconductor wafer 50, the semiconductor wafer 50 is cut into individual pieces. The separated semiconductor wafer is obtained as a semiconductor chip 51.
  • the semiconductor processing pressure-sensitive adhesive tape is peeled from the singulated semiconductor wafer (that is, a plurality of semiconductor chips).
  • the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape 1 includes an energy ray curable resin
  • the pressure-sensitive adhesive layer is cured by irradiating energy rays from an energy ray irradiation source 90. Reduce the adhesion of the layer.
  • the pickup tape 100 is attached to the back surface 51 b side of the plurality of semiconductor chips 51 and the ring frame 60.
  • the semiconductor processing adhesive tape is peeled off from the plurality of semiconductor chips 51 held on the pickup tape 100 to expose the circuit surface 51a of the semiconductor chip.
  • the dicing process is performed after the back surface grinding of the semiconductor wafer, but a so-called first dicing process may be performed. Specifically, after a groove having a depth of cut shallower than the wafer thickness is formed on the circuit forming surface (front surface) of the semiconductor wafer, an adhesive tape for semiconductor processing is applied to the circuit forming surface and the ring frame. To do. Similarly to the above, the thickness of the wafer may be reduced by grinding the back surface of the semiconductor wafer, and the semiconductor wafer may be separated into pieces by reaching the cut surface.
  • the pressure-sensitive adhesive layer on which the ring frame and the semiconductor wafer are bonded to the same surface has characteristics required when processing the semiconductor wafer and characteristics required after processing the semiconductor wafer.
  • the semiconductor processing pressure-sensitive adhesive tape according to the present embodiment can suppress slack during the processing of the semiconductor wafer, and exhibits good peelability even when the pressure-sensitive adhesive tape is peeled off from the ring frame after the processing of the semiconductor wafer. it can.
  • the energy ray-curable resin and a predetermined cross-linked structure are present in the pressure-sensitive adhesive layer.
  • the predetermined cross-linked structure can be easily obtained by using two types of cross-linking agents.
  • the measurement method and evaluation method in this example are as follows.
  • the pressure-sensitive adhesive having the composition shown in Table 1 was coated on a release sheet and dried. Seven days after coating, 0.3 g of the pressure-sensitive adhesive was weighed, wrapped in # 200 mesh, and immersed in ethyl acetate at 23 ° C. for 1 day. After soaking, the mesh was taken out, dried at 100 ° C. for 2 hours, and conditioned at 23 ° C. and 50 RH for 1 hour, and then the weight of the adhesive was measured. The gel fraction (%) was calculated from the following formula. ((Adhesive weight before immersion-Adhesive weight after immersion) / Adhesive weight before immersion) x 100
  • Example 4 an adhesive having a composition obtained by removing the energy ray curable resin from the adhesive was coated on a release sheet and dried. About the adhesive 7 days after coating, the gel fraction was measured by the same method as described above.
  • Adhesive strength after energy beam irradiation According to JIS Z0237 which prescribes the measuring method of adhesive strength, it measured by the following procedure.
  • UV irradiation was performed from the substrate side under the irradiation conditions of 230 mW / cm 2 illuminance and 500 mJ / cm 2 accumulated light intensity using a Lintec UV irradiation device (RAD-2000m / 12). Then, the pressure-sensitive adhesive layer was cured.
  • the pressure-sensitive adhesive sheet having the cured pressure-sensitive adhesive layer is peeled off from a stainless steel (SUS304) mirror surface plate using a universal tensile tester (Autograph AG-IS) manufactured by Shimadzu Corporation at a peeling angle of 180 ° and a peeling speed of 300 mm / min. It peeled and the adhesive force was measured. The obtained value was defined as the adhesive strength after energy beam irradiation.
  • the adhesive tape for semiconductor processing of Examples and Comparative Examples was attached to a ring frame made of SUS304 for 8-inch wafer and a 4-inch silicon wafer with RAD-2700.
  • the semiconductor processing adhesive tape affixed to the ring frame and the silicon wafer was placed on the grinding apparatus, the ring frame was pushed down to 4 mm downward, and the semiconductor processing adhesive tape was extended. Thereafter, the ring frame was released from depression, and the size of the slack was measured after 5 minutes, and the slack of the tape was evaluated according to the following criteria.
  • ⁇ No slack
  • ⁇ There is slack but there is no practical problem
  • ⁇ There is slack and there is practical problem
  • the silicon wafer was ground to a finished thickness of 150 ⁇ m with the ring frame pressed down. After grinding, the ring frame is returned to its original height, irradiated with ultraviolet rays (illuminance: 230 mW / cm 2 , light intensity: 190 mJ / cm 2 ), and then the semiconductor processing adhesive tape is peeled off from the ring frame. The peeled state was evaluated according to the following criteria. ⁇ : No peeling failure ⁇ : Generation of peeling failure (heavy peeling) ⁇ : Peeling failure occurred (tape stuck to the ring frame)
  • Example 1 Preparation of adhesive composition
  • BA butyl acrylate
  • AA acrylic acid
  • the above-mentioned pressure-sensitive adhesive composition was applied on the release surface of a release sheet (SP-PET 381031 manufactured by Lintec Corporation). Subsequently, drying by heating was performed to advance the crosslinking reaction, and the coating film of the pressure-sensitive adhesive composition was used as a pressure-sensitive adhesive layer. The thickness of the pressure-sensitive adhesive layer was 15 ⁇ m. Thereafter, the pressure-sensitive adhesive layer on the obtained release sheet was bonded to the corona-treated surface of an ethylene-methacrylic acid copolymer (EMAA) film (thickness: 80 ⁇ m) having a corona-treated one surface as a base material. Thus, an adhesive tape for semiconductor processing was obtained.
  • EEMAA ethylene-methacrylic acid copolymer
  • Examples 2 to 5 Comparative Examples 1 and 2
  • a semiconductor processing adhesive tape was obtained in the same manner as in Example 1 except that the composition of the adhesive was changed to the composition shown in Table 1.
  • Example 1 the gel fraction of the composition obtained by removing the energy ray curable resin from the adhesive is 75%.
  • Example 4 the composition of the composition obtained by removing the energy ray curable resin from the adhesive.
  • the gel fraction of the pressure-sensitive adhesive was 85%.
  • the gel fraction of the adhesive of the composition which removed the energy beam curable resin from the adhesive was 55%.
  • the adhesive tape for semiconductor processing of the present invention can be suitably used, for example, for processing a semiconductor wafer in a state of being attached to a ring frame and a semiconductor wafer.

Abstract

Provided is adhesive tape for semiconductor fabrication constituted by adhesive tape comprising a substrate and an adhesive layer provided on one side of the substrate, the adhesive tape being characterized in that, before energy irradiation of the adhesive layer, the adhesive layer has a gel fraction of 35% or more, the loss tangent of the adhesive layer at 50°C is less than 0.65, and, after energy irradiation of the adhesive layer, the adhesive strength of the adhesive layer is 3,100 mN/25 mm or less.

Description

半導体加工用粘着テープAdhesive tape for semiconductor processing
　本発明は、半導体加工用粘着テープに関する。特に、半導体ウエハを加工する際に回路面を保護するために好適に使用される半導体加工用粘着テープに関する。 The present invention relates to an adhesive tape for semiconductor processing. In particular, the present invention relates to an adhesive tape for semiconductor processing that is suitably used for protecting a circuit surface when processing a semiconductor wafer.
　各種電子機器に搭載される半導体チップは、回路が形成された半導体ウエハを個片化することにより得られる。電子機器は、小型化、多機能化が急速に進んでおり、半導体チップにも小型化、低背化、高密度化が求められている。チップを小型化および低背化するには、半導体ウエハの表面に回路を形成した後、半導体ウエハの裏面を研削して、チップの厚さ調整を行うことが一般的である。 Semiconductor chips mounted on various electronic devices are obtained by dividing a semiconductor wafer on which a circuit is formed. Electronic devices are rapidly becoming smaller and more multifunctional, and semiconductor chips are also required to be smaller, lower in profile and higher in density. In order to reduce the size and height of a chip, it is common to adjust the thickness of the chip by forming a circuit on the surface of the semiconductor wafer and then grinding the back surface of the semiconductor wafer.
　半導体ウエハの裏面研削時には、ウエハ表面の回路を保護し、かつ、半導体ウエハを保持するために、ウエハ表面にバックグラインドテープと呼ばれる粘着テープが貼付される。 When grinding the back surface of a semiconductor wafer, an adhesive tape called a back grind tape is attached to the wafer surface in order to protect the circuit on the wafer surface and hold the semiconductor wafer.
　裏面研削後の半導体ウエハは、ウエハを個片化するダイシング工程等の次工程に搬送される。しかしながら、裏面研削後の半導体ウエハは非常に薄く、粘着テープとともに反りやすい傾向にある。また、半導体ウエハは、剛性の低い粘着テープのみに保持されているため、搬送時に半導体ウエハに負荷が掛かり破損しやすくなる。 The semiconductor wafer after the back grinding is transferred to the next process such as a dicing process for separating the wafer into individual pieces. However, the semiconductor wafer after back grinding is very thin and tends to warp together with the adhesive tape. Further, since the semiconductor wafer is held only by the adhesive tape having low rigidity, the semiconductor wafer is easily loaded and damaged during transportation.
　そこで、特許文献１および２には、バックグラインドテープの周縁部を、裏面研削時に研削装置に装着されるリング状のフレーム（以降、リングフレームとも言う）にも貼り付けて、半導体ウエハを、バックグラインドテープを介してリングフレームに固定してから、裏面研削を行うことが記載されている。すなわち、金属製のリングフレームと半導体ウエハとバックグラインドテープとが一体化された状態で、チャックテーブル上に載置および固定され、グラインダーにより、半導体ウエハの裏面が研削される。 Therefore, in Patent Documents 1 and 2, the peripheral portion of the back grind tape is also attached to a ring-shaped frame (hereinafter also referred to as a ring frame) that is attached to a grinding device at the time of back surface grinding. It is described that the back surface grinding is performed after being fixed to the ring frame via a grind tape. That is, the metal ring frame, the semiconductor wafer, and the back grind tape are integrated and placed on the chuck table, and the back surface of the semiconductor wafer is ground by the grinder.
　半導体ウエハとリングフレームとが一体化することにより、裏面研削後の半導体ウエハを、剛性の高いリングフレームと共に次工程に搬送することができる。したがって、研削後の半導体ウエハが非常に薄くても、リングフレームにより半導体ウエハの反りが抑制される。さらに、搬送時にウエハに負荷がほとんど掛からないため、ウエハの破損を抑制することができる。 By integrating the semiconductor wafer and the ring frame, the semiconductor wafer after the back surface grinding can be transported to the next process together with a highly rigid ring frame. Therefore, even if the semiconductor wafer after grinding is very thin, warpage of the semiconductor wafer is suppressed by the ring frame. Further, since the load is hardly applied to the wafer during transfer, damage to the wafer can be suppressed.
　また、バックグラインドテープはリングフレームに固定された状態で、次工程に搬送されるので、次工程がダイシング工程である場合には、リングフレームに貼り付けられたバックグラインドテープがダイシングテープを兼ねることができる。以降、このような粘着シートを総称して、「半導体加工用粘着テープ」とも言う。 Also, since the back grind tape is fixed to the ring frame and transported to the next process, if the next process is a dicing process, the back grind tape affixed to the ring frame also serves as the dicing tape Can do. Hereinafter, such adhesive sheets are collectively referred to as “adhesive tape for semiconductor processing”.
特開平６－３０２５６９号公報Japanese Patent Laid-Open No. 6-302569 特開平１１－４５８６６号公報Japanese Patent Laid-Open No. 11-45866
　しかしながら、半導体ウエハはリングフレームに直接支持されている訳ではなく、バックグラインドテープに貼り付けられているので、バックグラインドテープには、半導体ウエハの荷重がかかる。この半導体ウエハは、裏面研削前のウエハであるため、裏面研削後のウエハに比べて重い。そのため、半導体ウエハの自重により、バックグラインドテープが弛んでしまうという問題があった。 However, the semiconductor wafer is not directly supported by the ring frame, but is attached to the back grind tape, so that the load of the semiconductor wafer is applied to the back grind tape. Since this semiconductor wafer is a wafer before the back surface grinding, it is heavier than the wafer after the back surface grinding. Therefore, there is a problem that the back grind tape is loosened due to the weight of the semiconductor wafer.
　また、特許文献１および２にも記載されているように、裏面研削時には、グラインダーとリングフレームとが接触しないように、リングフレーム側を押し下げる、あるいは、半導体ウエハが載置されているチャックテーブル側を押し上げることにより、バックグラインドテープは伸ばされる。 Further, as described in Patent Documents 1 and 2, at the time of back surface grinding, the ring frame side is pushed down so that the grinder and the ring frame do not contact each other, or the chuck table side on which the semiconductor wafer is placed By pushing up, the back grind tape is stretched.
　裏面研削終了後に、バックグラインドテープの伸びは開放されるが、裏面研削前のバックグラインドテープの状態まで復帰せずに、バックグラインドテープが弛んでしまうという問題があった。 The elongation of the back grind tape is released after the back surface grinding is completed, but there is a problem that the back grind tape is loosened without returning to the state of the back grind tape before the back surface grinding.
　さらに、裏面研削終了後には、半導体ウエハまたは半導体チップを他のテープに転写するために、半導体加工用粘着テープを半導体ウエハおよびリングフレームの両方から剥離する必要がある。当該粘着テープは半導体ウエハよりもリングフレームに強固に接着しているため、当該粘着テープの剥離時に、リングフレームに当該粘着テープの粘着剤の一部が残ったり、当該粘着テープ自体が破れて残ったりするという問題があった。このような糊残りが生じると、その後の工程において不具合が生じてしまう。 Furthermore, after finishing the back surface grinding, it is necessary to peel off the semiconductor processing adhesive tape from both the semiconductor wafer and the ring frame in order to transfer the semiconductor wafer or the semiconductor chip to another tape. Since the pressure-sensitive adhesive tape is more firmly bonded to the ring frame than the semiconductor wafer, when the pressure-sensitive adhesive tape is peeled off, a part of the pressure-sensitive adhesive of the pressure-sensitive adhesive tape remains on the ring frame or the pressure-sensitive adhesive tape itself remains torn. There was a problem. If such adhesive residue is generated, problems occur in subsequent processes.
　本発明は、このような実状に鑑みてなされ、粘着テープの弛みが抑制され、かつリングフレームからの剥離性が良好な半導体加工用粘着テープを提供することを目的とする。 The present invention has been made in view of such a situation, and an object of the present invention is to provide a pressure-sensitive adhesive tape for semiconductor processing in which the looseness of the pressure-sensitive adhesive tape is suppressed and the peelability from the ring frame is good.
　本発明の態様は、
　［１］基材と、基材の一方の面側に設けられた粘着剤層とを有する粘着テープであって、
　粘着剤層に対するエネルギー線照射前において、粘着剤層のゲル分率が３５％以上であり、５０℃における粘着剤層の損失正接が０．６５未満であり、
　粘着剤層に対するエネルギー線照射後において、粘着剤層の粘着力が３１００ｍＮ／２５ｍｍ以下であることを特徴とする半導体加工用粘着テープである。 Aspects of the present invention include
[1] An adhesive tape having a substrate and an adhesive layer provided on one surface side of the substrate,
Before the energy ray irradiation to the pressure-sensitive adhesive layer, the gel fraction of the pressure-sensitive adhesive layer is 35% or more, and the loss tangent of the pressure-sensitive adhesive layer at 50 ° C. is less than 0.65,
The adhesive tape for semiconductor processing, wherein the adhesive force of the adhesive layer is 3100 mN / 25 mm or less after energy beam irradiation to the adhesive layer.
　［２］粘着剤層が架橋構造とエネルギー線硬化性樹脂とを有することを特徴とする［１］に記載の半導体加工用粘着テープである。 [2] The adhesive tape for semiconductor processing according to [1], wherein the adhesive layer has a cross-linked structure and an energy ray curable resin.
　［３］架橋構造は、少なくともアクリル系重合体と架橋剤とから構成されることを特徴とする［２］に記載の半導体加工用粘着テープである。 [3] The adhesive tape for semiconductor processing according to [2], wherein the crosslinked structure is composed of at least an acrylic polymer and a crosslinking agent.
　［４］架橋構造のゲル分率が７０％以上９５％以下であることを特徴とする［３］に記載の半導体加工用粘着テープである。
　［５］半導体ウエハを加工する工程において、加工装置に固定されるリングフレームと半導体ウエハとが粘着剤層に貼付されることを特徴とする［１］から［４］のいずれかに記載の半導体加工用粘着テープである。 [4] The semiconductor processing pressure-sensitive adhesive tape according to [3], wherein the gel fraction of the crosslinked structure is 70% or more and 95% or less.
[5] The semiconductor according to any one of [1] to [4], wherein in the step of processing the semiconductor wafer, a ring frame fixed to the processing apparatus and the semiconductor wafer are attached to the adhesive layer. This is an adhesive tape for processing.
　本発明によれば、粘着テープの弛みが抑制され、かつリングフレームからの剥離性が良好な半導体加工用粘着テープを提供することができる。 According to the present invention, it is possible to provide an adhesive tape for semiconductor processing in which the looseness of the adhesive tape is suppressed and the peelability from the ring frame is good.
図１は、本発明の一実施形態に係る半導体加工用粘着テープの断面図である。FIG. 1 is a cross-sectional view of an adhesive tape for semiconductor processing according to an embodiment of the present invention. 図２Ａは、本発明の一実施形態に係る半導体加工用粘着テープを用いた半導体装置の製造方法を説明するための模式的な断面図である。FIG. 2A is a schematic cross-sectional view for explaining a method for manufacturing a semiconductor device using an adhesive tape for semiconductor processing according to an embodiment of the present invention. 図２Ｂは、図２Ａの続きの図である。FIG. 2B is a continuation of FIG. 2A. 図２Ｃは、図２Ｂの続きの図である。FIG. 2C is a continuation of FIG. 2B. 図２Ｄは、図２Ｃの続きの図である。FIG. 2D is a continuation of FIG. 2C. 図２Ｅは、図２Ｄの続きの図である。FIG. 2E is a continuation of FIG. 2D. 図２Ｆは、図２Ｅの続きの図である。FIG. 2F is a continuation of FIG. 2E.
　以下、本発明を、具体的な実施形態に基づき、以下の順序で詳細に説明する。 Hereinafter, the present invention will be described in detail in the following order based on specific embodiments.
　（１．半導体加工用粘着テープ）
　本実施形態に係る半導体加工用粘着テープ１は、図１に示すように、基材１０上に粘着剤層２０が積層された構成を有している。半導体加工用粘着テープは、図１に記載の構成に限定されず、本発明の効果が得られる限りにおいて、他の層を有していてもよい。たとえば、粘着剤層２０を被着体に貼り付けするまで粘着剤層２０を保護するために、粘着剤層２０の主面２０ａに剥離シートが形成されていてもよい。以下、半導体加工用粘着テープの構成要素について詳細に説明する。 (1. Adhesive tape for semiconductor processing)
The adhesive tape 1 for semiconductor processing according to the present embodiment has a configuration in which an adhesive layer 20 is laminated on a base material 10 as shown in FIG. The pressure-sensitive adhesive tape for semiconductor processing is not limited to the configuration shown in FIG. 1 and may have other layers as long as the effects of the present invention are obtained. For example, in order to protect the adhesive layer 20 until the adhesive layer 20 is attached to the adherend, a release sheet may be formed on the main surface 20a of the adhesive layer 20. Hereinafter, components of the adhesive tape for semiconductor processing will be described in detail.
　（１．１．粘着剤層）
　本実施形態では、半導体ウエハを加工（たとえば裏面研削）する前に、被着体（半導体ウエハを固定するリングフレームおよび半導体ウエハの表面）が粘着剤層２０の主面２０ａに貼り付けられる。そして、半導体ウエハの加工後に、半導体加工用粘着テープ、すなわち、粘着剤層２０が半導体ウエハおよびリングフレームから剥離される。したがって、粘着剤層は、被着体である半導体ウエハおよびリングフレームの両方に対して、適度な再剥離性を示す粘着力を有している。 (1.1. Adhesive layer)
In the present embodiment, the adherend (the ring frame for fixing the semiconductor wafer and the surface of the semiconductor wafer) is attached to the main surface 20a of the adhesive layer 20 before the semiconductor wafer is processed (for example, back grinding). Then, after processing the semiconductor wafer, the semiconductor processing pressure-sensitive adhesive tape, that is, the pressure-sensitive adhesive layer 20 is peeled from the semiconductor wafer and the ring frame. Therefore, the pressure-sensitive adhesive layer has an adhesive force showing an appropriate removability to both the semiconductor wafer and the ring frame that are adherends.
　粘着剤層２０の厚さは、特に制限されないが、好ましくは１μｍ以上５０μｍ以下、より好ましくは５μｍ以上３０μｍ以下、さらに好ましくは１２μｍ以上１８μｍ以下である。粘着剤層の厚さが薄すぎると、半導体ウエハの加工時における粘着剤層の粘着力が低い傾向にある。一方、厚すぎると、裏面研削中に、半導体ウエハの厚みがばらつく傾向にある。 The thickness of the pressure-sensitive adhesive layer 20 is not particularly limited, but is preferably 1 μm to 50 μm, more preferably 5 μm to 30 μm, and still more preferably 12 μm to 18 μm. If the thickness of the pressure-sensitive adhesive layer is too thin, the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer tends to be low during the processing of the semiconductor wafer. On the other hand, if it is too thick, the thickness of the semiconductor wafer tends to vary during backside grinding.
　本実施形態では、リングフレームおよび半導体ウエハが貼付される粘着剤層の主面は以下の物性を有している。以下の物性は、粘着剤層の主面において、少なくともリングフレームおよび半導体ウエハが貼付される領域において発現している。 In the present embodiment, the main surface of the adhesive layer to which the ring frame and the semiconductor wafer are attached has the following physical properties. The following physical properties are manifested on the main surface of the pressure-sensitive adhesive layer at least in the region where the ring frame and the semiconductor wafer are attached.
　（１．１．１．エネルギー線照射前のゲル分率）
　本実施形態では、粘着剤層に対するエネルギー線照射前において、粘着剤層のゲル分率が３５％以上である。エネルギー線照射前、すなわち、裏面研削等の工程においてゲル分率が上記の範囲内であることにより、粘着剤層に力が掛かった場合であっても、粘着剤層が変形しにくい。その結果、テープの弛みが抑制される傾向にある。 (1.1.1. Gel fraction before energy beam irradiation)
In the present embodiment, the gel fraction of the pressure-sensitive adhesive layer is 35% or more before energy ray irradiation to the pressure-sensitive adhesive layer. The adhesive layer is not easily deformed even when a force is applied to the adhesive layer before the energy ray irradiation, that is, in the step such as back grinding, the gel fraction is within the above range. As a result, tape slack tends to be suppressed.
　粘着剤層のゲル分率は３７％以上であることが好ましく、４０％以上であることがより好ましい。また、粘着剤層のゲル分率は７０％以下であることが好ましく、６０％以下であることがより好ましく、５０％以下であることがさらに好ましい。ゲル分率が大きすぎる場合には、テープの弛みは十分に抑制されるが、裏面研削時のテープの伸びが小さくなり、グラインダーがリングフレームに接触してしまう傾向にある。 The gel fraction of the pressure-sensitive adhesive layer is preferably 37% or more, and more preferably 40% or more. Moreover, it is preferable that the gel fraction of an adhesive layer is 70% or less, It is more preferable that it is 60% or less, It is further more preferable that it is 50% or less. When the gel fraction is too large, tape slack is sufficiently suppressed, but the tape elongation during back surface grinding becomes small and the grinder tends to come into contact with the ring frame.
　（１．１．２．エネルギー線照射前の損失正接）
　本実施形態では、５０℃における粘着剤層の損失正接（ｔａｎδ）が０．６５未満である。損失正接（ｔａｎδ）は、「損失弾性率／貯蔵弾性率」で定義され、動的粘弾性測定装置により対象物に与えた引張り応力やねじり応力等の応力に対する応答によって測定される値である。損失正接が上記の範囲内であることにより、粘着剤層に力が掛かった場合であっても、粘着剤層が変形しにくいので、テープの弛みが抑制される傾向にある。 (1.1.2. Loss tangent before energy beam irradiation)
In this embodiment, the loss tangent (tan δ) of the pressure-sensitive adhesive layer at 50 ° C. is less than 0.65. The loss tangent (tan δ) is defined as “loss elastic modulus / storage elastic modulus”, and is a value measured by a response to a stress such as a tensile stress or a torsional stress applied to an object by a dynamic viscoelasticity measuring apparatus. When the loss tangent is within the above range, even when a force is applied to the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is not easily deformed, so that the slack of the tape tends to be suppressed.
　粘着剤層の損失正接は０．６０以下であることが好ましく、０．５５以下であることがより好ましい。また、粘着剤層の損失正接は０．３０以上であることが好ましく、０．４０以上であることがより好ましい。損失正接が小さすぎる場合には、テープの弛みは十分に抑制されるが、裏面研削時のテープの伸びが小さくなり、グラインダーがリングフレームに接触するおそれがある。 The loss tangent of the pressure-sensitive adhesive layer is preferably 0.60 or less, and more preferably 0.55 or less. Further, the loss tangent of the pressure-sensitive adhesive layer is preferably 0.30 or more, and more preferably 0.40 or more. If the loss tangent is too small, the tape slack is sufficiently suppressed, but the tape elongation during back grinding becomes small, and the grinder may come into contact with the ring frame.
　（１．１．３．エネルギー線照射後の粘着力）
　粘着剤層に対するエネルギー線照射後において、粘着剤層の粘着力が３１００ｍＮ／２５ｍｍ以下である。エネルギー線照射後、すなわち、半導体加工用粘着テープをリングフレームから剥離する際に、粘着剤層の粘着力が上記の範囲内であることにより、ウエハだけでなく、リングフレームから良好に剥離することができる。 (1.1.3. Adhesive strength after energy beam irradiation)
After the energy ray irradiation to the pressure-sensitive adhesive layer, the pressure-sensitive adhesive strength of the pressure-sensitive adhesive layer is 3100 mN / 25 mm or less. After energy beam irradiation, that is, when peeling the adhesive tape for semiconductor processing from the ring frame, the pressure sensitive adhesive layer should be peeled well not only from the wafer but also from the ring frame because it is within the above range. Can do.
　エネルギー線照射後の粘着剤層の粘着力は３０００ｍＮ／２５ｍｍ以下であることが好ましく、２５００ｍＮ／２５ｍｍ以下であることがより好ましい。 The adhesive strength of the pressure-sensitive adhesive layer after irradiation with energy rays is preferably 3000 mN / 25 mm or less, and more preferably 2500 mN / 25 mm or less.
　粘着剤層が上記の（１．１．１．）から（１．１．３．）に示す物性を有することにより、裏面研削時には粘着テープの弛みが抑制され、裏面研削後にリングフレームから良好に剥離することができる。 The adhesive layer has the physical properties shown in the above (1.1.1.) To (1.1.3.), So that the slack of the adhesive tape is suppressed during back grinding, and it is excellent from the ring frame after back grinding. Can be peeled off.
　（１．２．粘着剤層の構造および構成成分）
　粘着剤層は上記の物性を有していれば、粘着剤層の構造および組成は特に限定されないが、本実施形態では、以下のような構造および構成成分を有していることが好ましい。 (1.2. Structure and components of pressure-sensitive adhesive layer)
The structure and composition of the pressure-sensitive adhesive layer are not particularly limited as long as the pressure-sensitive adhesive layer has the above physical properties, but in the present embodiment, it is preferable to have the following structure and components.
　本実施形態では、半導体ウエハおよびリングフレームからの粘着テープの剥離を良好とするために、エネルギー線照射前後における粘着剤層の粘着力の変化を利用している。すなわち、裏面研削等の加工工程では、粘着剤層に対してエネルギー線照射を行わずに、粘着テープと、リングフレームおよび半導体ウエハとの接着性を確保する。加工工程後にリングフレームから剥離する際には、粘着剤層にエネルギー線を照射して、粘着剤層の粘着力を低下させ、粘着テープをリングフレームから剥離しやすくしている。 In the present embodiment, the change in the adhesive force of the adhesive layer before and after energy beam irradiation is used in order to improve the peeling of the adhesive tape from the semiconductor wafer and the ring frame. That is, in processing steps such as back grinding, the adhesive layer is secured to the adhesive tape, the ring frame, and the semiconductor wafer without irradiating the adhesive layer with energy rays. When peeling from the ring frame after the processing step, the pressure-sensitive adhesive layer is irradiated with energy rays to reduce the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer, thereby making it easy to peel the pressure-sensitive adhesive tape from the ring frame.
　したがって、本実施形態に係る半導体加工用粘着テープの粘着剤層には、構成成分として、エネルギー線硬化性樹脂が含まれていることが好ましい。ところが、このようなエネルギー線硬化性樹脂は比較的に低分子量であり凝集性が低い。そのため、粘着剤層に、エネルギー線照射前のエネルギー線硬化性樹脂が含まれている場合、粘着剤層に力が掛かるとエネルギー線硬化性樹脂が動きやすい。その結果、粘着剤層の変形が生じやすく、テープの弛みを抑制することが困難となってしまう。 Therefore, it is preferable that the adhesive layer of the adhesive tape for semiconductor processing according to the present embodiment contains an energy ray curable resin as a constituent component. However, such an energy beam curable resin has a relatively low molecular weight and low cohesion. Therefore, when the energy ray curable resin before energy ray irradiation is contained in the pressure-sensitive adhesive layer, the energy ray curable resin easily moves when force is applied to the pressure-sensitive adhesive layer. As a result, the pressure-sensitive adhesive layer is easily deformed, and it becomes difficult to suppress the slack of the tape.
　そこで、エネルギー線硬化性樹脂を含有することにより得られる半導体加工用粘着テープの再剥離性を維持しつつ、半導体ウエハの加工時における半導体加工用粘着テープへの負荷に起因する粘着剤層の変形を抑制するために、本実施形態では、粘着剤層中に架橋構造を導入している。架橋構造が存在することにより、エネルギー線硬化性樹脂の動きが架橋構造により阻害され、上述したゲル分率および損失正接を上記の範囲内とすることが容易となり、しかもエネルギー線照射後における粘着力を十分に低下させることができる。 Therefore, deformation of the adhesive layer due to the load on the semiconductor processing adhesive tape during processing of the semiconductor wafer while maintaining the removability of the semiconductor processing adhesive tape obtained by containing the energy ray curable resin In this embodiment, a crosslinked structure is introduced in the pressure-sensitive adhesive layer. Due to the presence of the cross-linked structure, the movement of the energy beam curable resin is hindered by the cross-linked structure, and the above-described gel fraction and loss tangent can be easily within the above ranges, and the adhesive strength after irradiation with the energy beam. Can be sufficiently reduced.
　本実施形態では、上記の架橋構造は、官能基含有アクリル系重合体および架橋剤により形成されることが好ましい。したがって、粘着剤層は、官能基含有アクリル系重合体、架橋剤およびエネルギー線硬化性樹脂を有していることが好ましい。これらの構成成分について詳細に説明する。 In the present embodiment, the cross-linked structure is preferably formed of a functional group-containing acrylic polymer and a cross-linking agent. Therefore, the pressure-sensitive adhesive layer preferably has a functional group-containing acrylic polymer, a crosslinking agent, and an energy ray curable resin. These constituent components will be described in detail.
　（１．２．１．官能基含有アクリル系重合体）
　官能基含有アクリル系重合体としては、公知のアクリル系重合体であればよい。官能基含有アクリル系重合体は、１種類のアクリル系モノマーから形成された単独重合体であってもよいし、複数種類のアクリル系モノマーから形成された共重合体であってもよいし、１種類または複数種類のアクリル系モノマーとアクリル系モノマー以外のモノマーとから形成された共重合体であってもよい。 (1.2.1. Functional group-containing acrylic polymer)
The functional group-containing acrylic polymer may be a known acrylic polymer. The functional group-containing acrylic polymer may be a homopolymer formed from one type of acrylic monomer, or may be a copolymer formed from a plurality of types of acrylic monomers. It may be a copolymer formed from one kind or plural kinds of acrylic monomers and monomers other than acrylic monomers.
　本実施形態では、官能基含有アクリル系重合体は、アルキル（メタ）アクリレートと官能基含有モノマーとを共重合したアクリル系共重合体であることが好ましい。なお、本明細書においては、「（メタ）アクリレート」とは、「アクリレート」および「メタクリレート」の双方を示す語として用いており、他の類似用語についても同様である。 In this embodiment, the functional group-containing acrylic polymer is preferably an acrylic copolymer obtained by copolymerizing an alkyl (meth) acrylate and a functional group-containing monomer. In this specification, “(meth) acrylate” is used as a term indicating both “acrylate” and “methacrylate”, and the same applies to other similar terms.
　アルキル（メタ）アクリレートとしては、炭素数１～１８のアルキル基を有するアルキル（メタ）アクリレートが挙げられ、好ましくは炭素数１～８のアルキル基を有するアルキル（メタ）アクリレート、より好ましくは炭素数１～４のアルキル基を有するアルキル（メタ）アクリレートが挙げられる。 Examples of the alkyl (meth) acrylate include an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, preferably an alkyl (meth) acrylate having an alkyl group having 1 to 8 carbon atoms, more preferably a carbon number. Examples thereof include alkyl (meth) acrylates having 1 to 4 alkyl groups.
　アルキル（メタ）アクリレートとしては、メチル（メタ）アクリレート、エチル（メタ）アクリレート、ｎ－プロピル（メタ）アクリレート、イソプロピル（メタ）アクリレート、ｎ－ブチル（メタ）アクリレート、イソブチル（メタ）アクリレート、ｔ－ブチル（メタ）アクリレート、ｎ－ペンチル（メタ）アクリレート、ｎ－ヘキシル（メタ）アクリレート、２－エチルヘキシル（メタ）アクリレート、イソオクチル（メタ）アクリレート、ｎ－オクチル（メタ）アクリレート等が挙げられる。これらの中では、ブチルアクリレートが好ましい。 Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t- Examples include butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, and n-octyl (meth) acrylate. Of these, butyl acrylate is preferred.
　アルキル（メタ）アクリレートは、官能基含有アクリル系共重合体において１種のみが含まれていてもよいし、２種以上が含まれていてもよい。 In the functional group-containing acrylic copolymer, only one type of alkyl (meth) acrylate may be contained, or two or more types may be contained.
　アルキル（メタ）アクリレート由来の構成単位は、官能基含有アクリル系共重合体の全構成単位中、７０質量％以上であることが好ましく、８０質量％以上であることがより好ましい。一方、アルキル（メタ）アクリレート由来の構成単位は、９９質量％以下であることが好ましく、９０質量％以下であることがより好ましい。 The structural unit derived from alkyl (meth) acrylate is preferably 70% by mass or more, and more preferably 80% by mass or more, based on all structural units of the functional group-containing acrylic copolymer. On the other hand, the constituent unit derived from alkyl (meth) acrylate is preferably 99% by mass or less, and more preferably 90% by mass or less.
　官能基含有モノマーは、反応性官能基を含有するモノマーである。反応性官能基は、後述する架橋剤等の他の化合物と反応することが可能な官能基である。アクリル系共重合体は、官能基含有モノマー由来の構成単位を有することで、架橋剤により架橋される。 The functional group-containing monomer is a monomer containing a reactive functional group. The reactive functional group is a functional group capable of reacting with other compounds such as a crosslinking agent described later. An acrylic copolymer has a structural unit derived from a functional group-containing monomer, and is crosslinked by a crosslinking agent.
　反応性官能基としては、具体的には、カルボキシ基、ヒドロキシ基、エポキシ基等が挙げられる。これらの中では架橋剤との反応性が良好であるため、カルボキシ基がより好ましい。 Specific examples of the reactive functional group include a carboxy group, a hydroxy group, and an epoxy group. In these, since the reactivity with a crosslinking agent is favorable, a carboxy group is more preferable.
　官能基含有モノマーとしては、アクリル酸、メタクリル酸、クロトン酸、マレイン酸、イタコン酸、シトラコン酸などのエチレン性不飽和カルボン酸が例示される。また、ヒドロキシメチル（メタ）アクリレート、２－ヒドロキシエチル（メタ）アクリレート、２－ヒドロキシプロピル（メタ）アクリレート、３－ヒドロキシプロピル（メタ）アクリレート、２－ヒドロキシブチル（メタ）アクリレート、３－ヒドロキシブチル（メタ）アクリレート、４－ヒドロキシブチル（メタ）アクリレートなどのヒドロキシ基含有（メタ）アクリレートが例示される。また、ビニルアルコール、アリルアルコール等の不飽和アルコールが例示される。また、グリシジル（メタ）アクリレート、β－メチルグリシジル（メタ）アクリレート、（３，４－エポキシシクロヘキシル）メチル（メタ）アクリレート、３－エポキシシクロ－２－ヒドロキシプロピル（メタ）アクリレート等のエポキシ基含有（メタ）アクリレートが例示される。また、グリシジルクロトネート、アリルグリシジルエーテル等の非アクリル系エポキシ基含有モノマーが例示される。 Examples of functional group-containing monomers include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. Also, hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl ( Examples thereof include hydroxy group-containing (meth) acrylates such as (meth) acrylate and 4-hydroxybutyl (meth) acrylate. Moreover, unsaturated alcohols, such as vinyl alcohol and allyl alcohol, are illustrated. In addition, epoxy groups containing glycidyl (meth) acrylate, β-methylglycidyl (meth) acrylate, (3,4-epoxycyclohexyl) methyl (meth) acrylate, 3-epoxycyclo-2-hydroxypropyl (meth) acrylate and the like ( Examples include (meth) acrylates. Non-acrylic epoxy group-containing monomers such as glycidyl crotonate and allyl glycidyl ether are also exemplified.
　官能基含有モノマーは、アクリル系共重合体において１種のみが含まれていてもよいし、２種以上が含まれていてもよい。 Only one type of functional group-containing monomer may be included in the acrylic copolymer, or two or more types may be included.
　これらの中では、架橋剤との反応性の観点から、エチレン性不飽和カルボン酸が好ましく、中でもアクリル酸、メタクリル酸がより好ましく、アクリル酸がさらに好ましい。 Among these, from the viewpoint of reactivity with the crosslinking agent, ethylenically unsaturated carboxylic acid is preferable, among which acrylic acid and methacrylic acid are more preferable, and acrylic acid is more preferable.
　官能基含有モノマー由来の構成単位は、官能基を含有するアクリル系共重合体の全構成単位中、１質量％以上であることが好ましく、５質量％以上であることがより好ましい。一方、官能基含有モノマー由来の構成単位は、３０質量％以下であることが好ましく、１５質量％以下であることがより好ましい。 The structural unit derived from the functional group-containing monomer is preferably 1% by mass or more, and more preferably 5% by mass or more, in all the structural units of the acrylic copolymer containing the functional group. On the other hand, the constitutional unit derived from the functional group-containing monomer is preferably 30% by mass or less, and more preferably 15% by mass or less.
　官能基含有アクリル系重合体の重量平均分子量（Ｍｗ）は、塗工時の造膜性の観点から１万～２００万であることが好ましく、１０万～１５０万であることがより好ましい。なお、本明細書における重量平均分子量は、ゲルパーミエーションクロマトグラフィー（ＧＰＣ）法により測定したポリスチレン換算の値である。 The weight average molecular weight (Mw) of the functional group-containing acrylic polymer is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000 from the viewpoint of film forming properties at the time of coating. In addition, the weight average molecular weight in this specification is the value of polystyrene conversion measured by the gel permeation chromatography (GPC) method.
　また、官能基を含有するアクリル系重合体は、上述したアルキル（メタ）アクリレートおよび官能基含有モノマー以外の構成モノマーを含有していてもよい。具体的には、シクロアルキル基の炭素数が１～２０程度のシクロアルキル（メタ）アクリレート、ベンジル（メタ）アクリレート、イソボルニル（メタ）アクリレート、ジシクロペンタニル（メタ）アクリレート、ジシクロペンテニル（メタ）アクリレート、ジシクロペンテニルオキシエチル（メタ）アクリレートなどの環状骨格を有する（メタ）アクリレート；アクリルアミド、Ｎ－メチルアクリルアミド、Ｎ，Ｎ－ジメチルアクリルアミドなどのアクリルアミド化合物；酢酸ビニル、プロピオン酸ビニルなどのビニルエステル化合物；エチレン、プロピレン、イソブチレンなどのオレフィン；塩化ビニル、ビニリデンクロリドなどのハロゲン化オレフィン；スチレン、α－メチルスチレンなどのスチレン系単量体；ブタジエン、イソプレン、クロロプレンなどのジエン系単量体；アクリロニトリル、メタクリロニトリルなどのニトリル系単量体などが挙げられる。 Moreover, the acrylic polymer containing a functional group may contain a constituent monomer other than the alkyl (meth) acrylate and the functional group-containing monomer described above. Specifically, cycloalkyl (meth) acrylate having about 1 to 20 carbon atoms in the cycloalkyl group, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meta ) (Meth) acrylates having a cyclic skeleton such as acrylate and dicyclopentenyloxyethyl (meth) acrylate; acrylamide compounds such as acrylamide, N-methylacrylamide and N, N-dimethylacrylamide; vinyl such as vinyl acetate and vinyl propionate Ester compound; Olefin such as ethylene, propylene and isobutylene; Halogenated olefin such as vinyl chloride and vinylidene chloride; Styrenic monomer such as styrene and α-methylstyrene; Diene monomers such as chloroprene; acrylonitrile, and the like methacrylonitrile nitrile monomers such.
　（１．２．２．架橋剤）
　架橋剤としては、粘着剤層が上記の特性を満足することが容易な架橋構造を形成可能な架橋剤であれば特に制限されない。本実施形態では、このような架橋構造として、比較的に緩く架橋した構造を主として形成し、当該構造中に、部分的に比較的に強く架橋した構造を存在させている。比較的に緩く架橋した構造の一部が、比較的に強く架橋した構造となっていることにより、上記の粘着剤層の物性を満足させることが容易となる。 (1.2.2. Crosslinking agent)
The cross-linking agent is not particularly limited as long as the pressure-sensitive adhesive layer can form a cross-linking structure that easily satisfies the above characteristics. In the present embodiment, as such a crosslinked structure, a relatively loosely crosslinked structure is mainly formed, and a structure that is partially relatively strongly crosslinked is present in the structure. A part of the structure that is relatively loosely crosslinked has a structure that is relatively strongly crosslinked, so that it is easy to satisfy the physical properties of the pressure-sensitive adhesive layer.
　このような架橋構造を形成するため、官能基を含有するアクリル系共重合体に対する架橋剤として、少なくとも２種類の架橋剤を用いる。このようにすることにより、架橋構造中に、比較的に緩く架橋した構造と、比較的に強く架橋した構造と、を共存させることが容易となる。 In order to form such a crosslinked structure, at least two kinds of crosslinking agents are used as a crosslinking agent for the acrylic copolymer containing a functional group. By doing in this way, it becomes easy to make the crosslinked structure coexist with a relatively loosely crosslinked structure and a relatively strongly crosslinked structure.
　具体的には、比較的に緩く架橋した構造を形成する架橋剤として、ポリイソシアネート系架橋剤を用い、比較的に強く架橋した構造を形成する架橋剤として、エポキシ系架橋剤を用いることが好ましい。 Specifically, it is preferable to use a polyisocyanate-based crosslinking agent as a crosslinking agent that forms a relatively loosely crosslinked structure, and an epoxy-based crosslinking agent as a crosslinking agent that forms a relatively strongly crosslinked structure. .
　これらの架橋剤は、官能基含有アクリル系重合体中の官能基と反応して、官能基含有アクリル系重合体を架橋する。ポリイソシアネート系架橋剤とエポキシ系架橋剤とでは、架橋の程度が異なっており、これらの架橋剤を用いることにより、エネルギー線照射前のゲル分率および損失正接と、エネルギー線照射後の粘着力とを両立可能な架橋構造を形成することができる。すなわち、得られる架橋構造の架橋の程度を好ましい範囲に制御することができる。 These crosslinking agents react with the functional groups in the functional group-containing acrylic polymer to crosslink the functional group-containing acrylic polymer. The degree of crosslinking differs between the polyisocyanate crosslinking agent and the epoxy crosslinking agent. By using these crosslinking agents, the gel fraction and loss tangent before energy beam irradiation, and the adhesive strength after energy beam irradiation. Can be formed. That is, the degree of crosslinking of the resulting crosslinked structure can be controlled within a preferred range.
　ポリイソシアネート系架橋剤は、１分子当たりイソシアネート基を２個以上有する化合物である。具体的には、トリレンジイソシアネート、ジフェニルメタンジイソシアネート、キシリレンジイソシアネート等の芳香族ポリイソシアネート；ヘキサメチレンジイソシアネート等の脂肪族ポリイソシアネート；イソホロンジイソシアネート、水素添加ジフェニルメタンジイソシアネート等の脂環式ポリイソシアネートなどが挙げられる。また、それらのビウレット体、イソシアヌレート体、さらには、それらとエチレングリコール、プロピレングリコール、ネオペンチルグリコール、トリメチロールプロパン、ヒマシ油等の低分子活性水素含有化合物との反応物であるアダクト体などが挙げられる。ポリイソシアネート系架橋剤は、１種のみが含まれていてもよいし、２種以上が含まれていてもよい。 The polyisocyanate-based crosslinking agent is a compound having two or more isocyanate groups per molecule. Specific examples include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate; alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate. . In addition, biuret bodies, isocyanurate bodies, and adduct bodies that are a reaction product of these with low molecular active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, etc. Can be mentioned. As for polyisocyanate type crosslinking agent, only 1 type may be contained and 2 or more types may be contained.
　エポキシ系架橋剤としては、たとえば、１，３－ビス（Ｎ，Ｎ’－ジグリシジルアミノメチル）シクロヘキサン、Ｎ，Ｎ，Ｎ’，Ｎ’－テトラグリシジル－ｍ－キシレンジアミン、エチレングリコールジグリシジルエーテル、１，６－ヘキサンジオールジグリシジルエーテル、トリメチロールプロパンジグリシジルエーテル、ジグリシジルアニリン、ジグリシジルアミン等が挙げられる。エポキシ系架橋剤は、１種のみが含まれていてもよいし、２種以上が含まれていてもよい。 Examples of the epoxy-based crosslinking agent include 1,3-bis (N, N′-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, and ethylene glycol diglycidyl ether. 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidylaniline, diglycidylamine and the like. As for an epoxy type crosslinking agent, only 1 type may be contained and 2 or more types may be contained.
　ポリイソシアネート系架橋剤の含有量は、官能基含有アクリル系共重合体１００質量部に対し、５質量部以上であることが好ましい。一方、当該含有量は１５質量部以下であることが好ましい。 The content of the polyisocyanate-based crosslinking agent is preferably 5 parts by mass or more with respect to 100 parts by mass of the functional group-containing acrylic copolymer. On the other hand, the content is preferably 15 parts by mass or less.
　また、エポキシ系架橋剤の含有量は、官能基含有アクリル系共重合体１００質量部に対し、０．０１質量部以上であることが好ましく、０．０３質量部以上であることがより好ましい。一方、当該含有量は０．５質量部以下であることが好ましく、０．３質量部以下であることがより好ましく、０．１質量部以下であることがさらに好ましい。 In addition, the content of the epoxy crosslinking agent is preferably 0.01 parts by mass or more, and more preferably 0.03 parts by mass or more with respect to 100 parts by mass of the functional group-containing acrylic copolymer. On the other hand, the content is preferably 0.5 parts by mass or less, more preferably 0.3 parts by mass or less, and further preferably 0.1 parts by mass or less.
　ポリイソシアネート系架橋剤およびエポキシ系架橋剤の含有量が上記の範囲内にあると、半導体ウエハおよびリングフレームに対するエネルギー線照射前の半導体加工用粘着テープの粘着力を調整することが容易となる。また、半導体加工用粘着テープの製造後、過度に長い養生期間を要することなく粘着特性が安定する。 When the content of the polyisocyanate-based crosslinking agent and the epoxy-based crosslinking agent is within the above range, it becomes easy to adjust the adhesive strength of the semiconductor processing adhesive tape before energy beam irradiation to the semiconductor wafer and the ring frame. Moreover, after the production of the adhesive tape for semiconductor processing, the adhesive property is stabilized without requiring an excessively long curing period.
　また、本実施形態では、架橋構造のゲル分率、すなわち、官能基含有アクリル系重合体と架橋剤とから形成される架橋構造のゲル分率が、７０％以上９５％以下であることが好ましい。上述した粘着剤層のゲル分率は、架橋構造だけでなく、比較的に低分子量であるエネルギー線硬化性樹脂も考慮されたゲル分率であるため、エネルギー線硬化性樹脂の量および分子量に左右される。たとえば、低分子量のエネルギー線硬化性樹脂が多く含まれていると、粘着剤層のゲル分率は低くなる傾向にある。一方、架橋構造のゲル分率は、エネルギー線硬化性樹脂の影響を排除しているので、架橋の程度をより反映していると考えられる。本実施形態では、架橋構造のゲル分率は、粘着剤層のゲル分率よりも大きいことが好ましい。 In this embodiment, the gel fraction of the crosslinked structure, that is, the gel fraction of the crosslinked structure formed from the functional group-containing acrylic polymer and the crosslinking agent is preferably 70% or more and 95% or less. . The gel fraction of the pressure-sensitive adhesive layer described above is a gel fraction that takes into consideration not only the crosslinked structure but also the energy ray-curable resin having a relatively low molecular weight. It depends. For example, if a large amount of low molecular weight energy ray curable resin is contained, the gel fraction of the pressure-sensitive adhesive layer tends to be low. On the other hand, since the gel fraction of the crosslinked structure excludes the influence of the energy ray curable resin, it is considered that the degree of crosslinking is more reflected. In this embodiment, it is preferable that the gel fraction of a crosslinked structure is larger than the gel fraction of an adhesive layer.
　（１．２．３．エネルギー線硬化性樹脂）
　エネルギー線硬化性樹脂は、分子内に、エネルギー線照射により硬化可能な不飽和基を有する樹脂である。このような不飽和基としては、（メタ）アクリロイル基、ビニル基等が例示される。 (1.2.3. Energy ray curable resin)
The energy ray curable resin is a resin having an unsaturated group curable by irradiation with energy rays in the molecule. Examples of such unsaturated groups include (meth) acryloyl groups and vinyl groups.
　本実施形態では、エネルギー線硬化性樹脂は、低分子量化合物（単官能型、多官能型のモノマーおよびオリゴマー）であることが好ましい。また、上記の架橋構造は熱架橋により形成されるので、エネルギー線照射前の粘着力を確保するために、エネルギー線硬化性樹脂は熱架橋しにくいものが好ましい。 In the present embodiment, the energy ray curable resin is preferably a low molecular weight compound (monofunctional and polyfunctional monomers and oligomers). Moreover, since said crosslinked structure is formed by thermal crosslinking, in order to ensure the adhesive force before energy beam irradiation, what is hard to carry out thermal crosslinking of energy beam curable resin is preferable.
　このような低分子量のエネルギー線硬化性樹脂としては、トリメチロールプロパントリアクリレート、テトラメチロールメタンテトラアクリレート、ペンタエリスリトールトリアクリレート、ジペンタエリスリトールモノヒドロキシペンタアクリレート、ジペンタエリスリトールヘキサアクリレート、１，４－ブチレングリコールジアクリレート、１，６－ヘキサンジオールジアクリレート、あるいは、ジシクロペンタジエンジメトキシジアクリレート、イソボルニルアクリレートなどの環状脂肪族骨格含有アクリレート；ポリエチレングリコールジアクリレート、オリゴエステルアクリレート、ウレタンアクリレートオリゴマー、エポキシ変性アクリレート、ポリエーテルアクリレート、イタコン酸オリゴマーなどのアクリレート系化合物等が例示される。これらは１種でもよいし、２種以上であってもよい。 Examples of such low molecular weight energy ray curable resins include trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butylene. Cycloaliphatic skeleton-containing acrylates such as glycol diacrylate, 1,6-hexanediol diacrylate, dicyclopentadiene dimethoxydiacrylate, and isobornyl acrylate; polyethylene glycol diacrylate, oligoester acrylate, urethane acrylate oligomer, epoxy modified Acrylate compounds such as acrylate, polyether acrylate, itaconic acid oligomer Like it is exemplified. These may be one type or two or more types.
　これらの中でも、多官能型モノマーまたはオリゴマーであることがより好ましく、多官能型ウレタン（メタ）アクリレートオリゴマーであることが特に好ましい。 Among these, a polyfunctional monomer or oligomer is more preferable, and a polyfunctional urethane (meth) acrylate oligomer is particularly preferable.
　エネルギー線硬化性樹脂の分子量（オリゴマーの場合は重量平均分子量）は、５００以上であることが好ましく、１０００以上であることがより好ましい。一方、当該分子量は１００００以下であることが好ましく、７０００以下であることがより好ましく、５０００以下であることがさらに好ましく、３０００以下であることが特に好ましい。エネルギー線硬化性樹脂の分子量が上記の範囲内であることで、エネルギー線照射前には、所定の粘着力を有し、エネルギー線照射後には、リングフレームから剥離可能な程度に粘着力を低下させることが容易となる。 The molecular weight (weight average molecular weight in the case of oligomer) of the energy beam curable resin is preferably 500 or more, and more preferably 1000 or more. On the other hand, the molecular weight is preferably 10,000 or less, more preferably 7000 or less, further preferably 5000 or less, and particularly preferably 3000 or less. When the molecular weight of the energy ray curable resin is within the above range, it has a predetermined adhesive strength before irradiation with energy rays, and the adhesive strength is reduced to such an extent that it can be peeled off from the ring frame after irradiation with energy rays. It becomes easy to make.
　また、比較的低分子量（２０００未満）のエネルギー線硬化性樹脂と比較的高分子量（２０００以上）のエネルギー線硬化性樹脂とを併用することにより、エネルギー線照射前の粘着力とエネルギー線照射後の粘着力との調整が容易となる。 In addition, by using a combination of a relatively low molecular weight (less than 2000) energy beam curable resin and a relatively high molecular weight (2000 or more) energy beam curable resin, adhesive strength before energy beam irradiation and after energy beam irradiation It becomes easy to adjust the adhesive strength.
　エネルギー線硬化性樹脂の含有量は、官能基含有アクリル系共重合体１００質量部に対し、５０質量部以上であることが好ましく、１００質量部以上であることがより好ましい。一方、当該含有量は２５０質量部以下であることが好ましく、２００質量部以下であることがより好ましい。エネルギー線硬化性樹脂の含有量が上記の範囲内であることで、エネルギー線照射前には、所定の粘着力を有し、エネルギー線照射後には、リングフレームから剥離可能な程度に粘着力を低下させることが容易となる。 The content of the energy ray curable resin is preferably 50 parts by mass or more and more preferably 100 parts by mass or more with respect to 100 parts by mass of the functional group-containing acrylic copolymer. On the other hand, the content is preferably 250 parts by mass or less, and more preferably 200 parts by mass or less. The content of the energy ray curable resin is within the above range, so that it has a predetermined adhesive force before irradiation with energy rays, and has an adhesive force that can be peeled off from the ring frame after irradiation with energy rays. It becomes easy to lower.
　粘着剤層を硬化させるためのエネルギー線としては、紫外線、電子線などが挙げられる。これらのうちでも、比較的照射設備の導入の容易な紫外線が好ましい。 Examples of energy rays for curing the pressure-sensitive adhesive layer include ultraviolet rays and electron beams. Among these, ultraviolet rays that are relatively easy to introduce irradiation equipment are preferable.
　紫外線を用いる場合には、取り扱いの容易さから波長２００～３８０ｎｍ程度の紫外線を含む近紫外線を用いることが好ましい。光量としては、粘着剤層が有するエネルギー線硬化性基の種類や、半導体加工用粘着テープの厚さに応じて適宜選択すればよく、通常５０～５００ｍＪ／ｃｍ２程度であり、１００～４５０ｍＪ／ｃｍ２が好ましく、２００～４００ｍＪ／ｃｍ２がより好ましい。また、紫外線照度は、通常５０～５００ｍＷ／ｃｍ２程度であり、１００～４５０ｍＷ／ｃｍ２が好ましく、２００～４００ｍＷ／ｃｍ２がより好ましい。紫外線源としては特に制限はなく、例えば高圧水銀ランプ、メタルハライドランプ、ＵＶ－ＬＥＤなどが用いられる。 When ultraviolet rays are used, it is preferable to use near ultraviolet rays including ultraviolet rays having a wavelength of about 200 to 380 nm for ease of handling. The amount of light may be appropriately selected according to the type of energy ray curable group of the pressure-sensitive adhesive layer and the thickness of the pressure-sensitive adhesive tape for semiconductor processing, and is usually about 50 to 500 mJ / cm 2 , and is 100 to 450 mJ / cm 2 is preferable, and 200 to 400 mJ / cm 2 is more preferable. The ultraviolet illumination is usually 50 ~ 500mW / cm 2 or so, preferably 100 ~ 450mW / cm 2, more preferably 200 ~ 400mW / cm 2. The ultraviolet light source is not particularly limited, and for example, a high pressure mercury lamp, a metal halide lamp, a UV-LED, or the like is used.
　（１．２．４．その他の成分）
　また、粘着剤層は、その他の成分として、染料、顔料、劣化防止剤、帯電防止剤、難燃剤、シリコーン化合物、連鎖移動剤、可塑剤、光重合開始剤等を含有してもよい。 (1.2.4. Other components)
The pressure-sensitive adhesive layer may contain other components such as dyes, pigments, deterioration inhibitors, antistatic agents, flame retardants, silicone compounds, chain transfer agents, plasticizers, and photopolymerization initiators.
　粘着剤層が、エネルギー線硬化性樹脂を含む場合、光重合開始剤を含有させることにより、硬化が十分行われ、エネルギー線照射後の粘着力をリングフレームから良好に剥離可能な程度まで下げることができる。 When the pressure-sensitive adhesive layer contains an energy ray curable resin, by containing a photopolymerization initiator, the curing is sufficiently performed and the adhesive strength after irradiation with the energy ray is lowered to a level that can be satisfactorily peeled from the ring frame. Can do.
　光重合開始剤としては、ベンゾイン化合物、アセトフェノン化合物、アシルフォスフィンオキサイド化合物、チタノセン化合物、チオキサントン化合物、パーオキサイド化合物等の光開始剤、アミンやキノン等の光増感剤などが挙げられる。具体的には、α－ヒドロキシシクロヘキシルフェニルケトン、ベンゾイン、ベンゾインメチルエーテル、ベンゾインエチルエーテル、ベンゾインイソプロピルエーテル、ベンジルジフェニルサルファイド、テトラメチルチウラムモノサルファイド、アゾビスイソブチロニトリル、ジベンジル、ジアセチル、β－クロールアンスラキノン、２，４，６－トリメチルベンゾイルジフェニルフォスフィンオキサイドなどが例示される。エネルギー線として紫外線を用いる場合には、光重合開始剤を配合することにより照射時間、照射量を少なくすることができる。 Examples of photopolymerization initiators include photoinitiators such as benzoin compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, thioxanthone compounds, and peroxide compounds, and photosensitizers such as amines and quinones. Specifically, α-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, dibenzyl, diacetyl, β-chlore Examples include anthraquinone and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. When ultraviolet rays are used as energy rays, the irradiation time and irradiation amount can be reduced by blending a photopolymerization initiator.
　（１．３．基材）
　本実施形態に係る半導体加工用粘着テープ１の基材１０は、半導体ウエハの加工時において、グラインダーとリングフレームとが接触しない程度に伸び、かつ粘着テープが破断しない材料から構成されていれば特に制限されない。 (1.3. Substrate)
The base material 10 of the adhesive tape 1 for semiconductor processing according to the present embodiment is particularly preferably formed of a material that extends to such a degree that the grinder and the ring frame do not come into contact with each other and that does not break the adhesive tape when processing a semiconductor wafer. Not limited.
　具体的には、エチレン－酢酸ビニル共重合体フィルム、エチレン－（メタ）アクリル酸共重合体フィルム、エチレン－（メタ）アクリル酸エステル共重合体フィルム等のエチレン系共重合体フィルム；低密度ポリエチレン（ＬＤＰＥ）フィルム、直鎖低密度ポリエチレン（ＬＬＤＰＥ）フィルム、高密度ポリエチレン（ＨＤＰＥ）フィルム等のポリエチレンフィルム、ポリプロピレンフィルム、ポリブテンフィルム、ポリブタジエンフィルム、ポリメチルペンテンフィルム、エチレン－ノルボルネン共重合体フィルム、ノルボルネン樹脂フィルム等のポリオレフィン系フィルム；ポリ塩化ビニルフィルム、塩化ビニル共重合体フィルム等のポリ塩化ビニル系フィルム；ポリウレタンフィルムなどが挙げられる。 Specifically, ethylene-based copolymer films such as ethylene-vinyl acetate copolymer film, ethylene- (meth) acrylic acid copolymer film, ethylene- (meth) acrylic acid ester copolymer film; low density polyethylene (LDPE) film, polyethylene film such as linear low density polyethylene (LLDPE) film, high density polyethylene (HDPE) film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, ethylene-norbornene copolymer film, norbornene Examples thereof include polyolefin films such as resin films; polyvinyl chloride films such as polyvinyl chloride films and vinyl chloride copolymer films; polyurethane films and the like.
　また、これらの架橋フィルム、アイオノマーフィルムのような変性フィルムも用いることができる。上記の基材１０はこれらの１種からなるフィルムでもよいし、これらを２種類以上組み合わせた積層フィルムであってもよい。 Also, modified films such as these crosslinked films and ionomer films can be used. The substrate 10 may be a film made of one of these, or a laminated film in which two or more of these are combined.
　また、基材１０において、粘着剤層２０が形成される面には、コロナ処理が施されていてもよいし、プライマー層が設けられていてもよい。 Moreover, in the base material 10, the surface on which the pressure-sensitive adhesive layer 20 is formed may be subjected to corona treatment or may be provided with a primer layer.
　本実施形態では、基材１０を構成するフィルムは、エチレン系共重合体フィルムおよびポリオレフィン系フィルムから選ばれる少なくとも１種であることが好ましい。 In the present embodiment, the film constituting the substrate 10 is preferably at least one selected from an ethylene copolymer film and a polyolefin film.
　基材１０の厚さは、本実施形態に係る半導体加工用粘着テープ１が本発明の効果を奏する限りにおいて限定されない。本実施形態では、好ましくは２０μｍ以上４５０μｍ以下、より好ましくは２５μｍ以上４００μｍ以下、特に好ましくは５０μｍ以上３５０μｍ以下の範囲にある。 The thickness of the base material 10 is not limited as long as the adhesive tape 1 for semiconductor processing according to this embodiment exhibits the effects of the present invention. In the present embodiment, the thickness is preferably 20 μm or more and 450 μm or less, more preferably 25 μm or more and 400 μm or less, and particularly preferably 50 μm or more and 350 μm or less.
　（２．半導体加工用粘着テープの製造方法）
　本実施形態に係る半導体加工用粘着テープを製造する方法は、基材の一方の面に粘着剤層を形成できる方法であれば特に制限されず、公知の方法を用いればよい。 (2. Manufacturing method of adhesive tape for semiconductor processing)
The method for producing the adhesive tape for semiconductor processing according to the present embodiment is not particularly limited as long as it can form an adhesive layer on one surface of the substrate, and a known method may be used.
　まず、粘着剤層を形成するための組成物として、たとえば、上述した構成成分（官能基含有アクリル系重合体、架橋剤、エネルギー線硬化性樹脂）を含有する粘着剤組成物、または、当該粘着剤組成物を溶媒等により希釈した組成物を調製する。 First, as a composition for forming the pressure-sensitive adhesive layer, for example, a pressure-sensitive adhesive composition containing the above-described components (functional group-containing acrylic polymer, crosslinking agent, energy ray curable resin), or the pressure-sensitive adhesive A composition is prepared by diluting the agent composition with a solvent or the like.
　溶媒としては、たとえば、メチルエチルケトン、アセトン、酢酸エチル、テトラヒドロフラン、ジオキサン、シクロヘキサン、ｎ－ヘキサン、トルエン、キシレン、ｎ－プロパノール、イソプロパノール等の有機溶剤が挙げられる。 Examples of the solvent include organic solvents such as methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, n-propanol, and isopropanol.
　そして、この粘着剤組成物等を、基材上に、スピンコート法、スプレーコート法、バーコート法、ナイフコート法、ロールコート法、ブレードコート法、ダイコート法、グラビアコート法等の公知の方法により塗布し、加熱し乾燥させて基材上に粘着剤層を形成する。あるいは、剥離シートの剥離処理面に、粘着剤組成物等を塗布し、加熱し乾燥させて剥離シート上に粘着剤層を形成し、その後、その剥離シート上の粘着剤層と基材とを貼り合わせて、基材上に、粘着剤層、及び剥離シートがこの順に設けられた半導体加工用粘着テープを製造してもよい。 And this adhesive composition, etc., on the substrate, known methods such as spin coating method, spray coating method, bar coating method, knife coating method, roll coating method, blade coating method, die coating method, gravure coating method, etc. Is applied, heated and dried to form an adhesive layer on the substrate. Alternatively, an adhesive composition or the like is applied to the release treatment surface of the release sheet, heated and dried to form an adhesive layer on the release sheet, and then the adhesive layer and the substrate on the release sheet are formed. The adhesive tape for a semiconductor processing by which the adhesive layer and the peeling sheet were provided in this order on the base material may be manufactured by bonding.
　塗布後の乾燥条件としては、たとえば、８０～１５０℃の温度で３０秒～５分間加熱すればよい。粘着剤組成物等が架橋剤を含有する場合には、加熱により架橋反応が生じるので、架橋反応を十分に進行させるために、上記の乾燥の条件（温度、時間など）を変えてもよいし、加熱処理を別途設けてもよい。さらに、通常、基材１０に粘着剤層２０を形成した後、得られた半導体加工用粘着テープを、たとえば２３℃、相対湿度５０％の環境に１週間程度静置する養生を行う。 As drying conditions after coating, for example, heating at a temperature of 80 to 150 ° C. for 30 seconds to 5 minutes may be performed. When the pressure-sensitive adhesive composition or the like contains a cross-linking agent, a cross-linking reaction is caused by heating. Therefore, in order to sufficiently advance the cross-linking reaction, the drying conditions (temperature, time, etc.) may be changed. A heat treatment may be separately provided. Furthermore, usually, after the pressure-sensitive adhesive layer 20 is formed on the base material 10, the resulting semiconductor processing pressure-sensitive adhesive tape is cured for about one week in an environment of, for example, 23 ° C. and a relative humidity of 50%.
　（３．半導体装置の製造方法）
　本実施形態に係る半導体加工用粘着テープを用いた半導体装置の製造方法の一例として、半導体ウエハから半導体装置としての回路が形成された半導体チップを製造する方法を図２Ａから図２Ｆを用いて説明する。 (3. Manufacturing method of semiconductor device)
As an example of a method for manufacturing a semiconductor device using an adhesive tape for semiconductor processing according to the present embodiment, a method for manufacturing a semiconductor chip on which a circuit as a semiconductor device is formed from a semiconductor wafer will be described with reference to FIGS. 2A to 2F. To do.
　まず、図２Ａに示すように、半導体ウエハ５０の回路が形成された面（表面５０ａ）とリングフレーム６０とを半導体加工用粘着テープ１の粘着剤層の一方の主面に貼付して、回路面を保護しつつ、半導体ウエハ５０を、半導体加工用粘着テープ１を介してリングフレーム６０に固定する。 First, as shown in FIG. 2A, the surface (surface 50a) on which the circuit of the semiconductor wafer 50 is formed and the ring frame 60 are affixed to one main surface of the adhesive layer of the semiconductor processing adhesive tape 1. The semiconductor wafer 50 is fixed to the ring frame 60 via the semiconductor processing adhesive tape 1 while protecting the surface.
　半導体ウエハは、シリコンウエハであってもよく、またガリウム・砒素などの化合物半導体ウエハであってもよい。また、回路を形成する方法は公知の方法を採用すればよい。所定の回路が形成された半導体ウエハの研削前の厚みは特に限定はされないが、通常は５００～１０００μｍ程度である。 The semiconductor wafer may be a silicon wafer or a compound semiconductor wafer such as gallium / arsenic. A known method may be adopted as a method for forming the circuit. The thickness of the semiconductor wafer on which the predetermined circuit is formed is not particularly limited, but is usually about 500 to 1000 μm.
　続いて、半導体ウエハが、研削装置のチャックテーブル上に載置され、リングフレームが研削装置に固定される。このとき、図２Ｂに示すように、研削装置において、グラインダー７０とリングフレーム６０との接触を防止するために、リングフレーム６０側を押し下げる、あるいは、チャックテーブル７５側を押し上げる。これに伴い、半導体加工用粘着テープ１は伸び、この状態で半導体ウエハ５０の裏面５０ｂがグラインダー７０により研削される。 Subsequently, the semiconductor wafer is placed on the chuck table of the grinding device, and the ring frame is fixed to the grinding device. At this time, as shown in FIG. 2B, in the grinding apparatus, the ring frame 60 side is pushed down or the chuck table 75 side is pushed up in order to prevent contact between the grinder 70 and the ring frame 60. Along with this, the semiconductor processing adhesive tape 1 is stretched, and in this state, the back surface 50 b of the semiconductor wafer 50 is ground by the grinder 70.
　半導体ウエハ５０が所定の厚みまで研削されると、裏面研削が終了し、リングフレーム６０側またはチャックテーブル７５側が当初の位置に戻り、半導体加工用粘着テープ１の伸びが開放される。 When the semiconductor wafer 50 is ground to a predetermined thickness, the back surface grinding is finished, the ring frame 60 side or the chuck table 75 side returns to the original position, and the elongation of the adhesive tape 1 for semiconductor processing is released.
　裏面研削後、半導体加工用粘着テープにエネルギー線を照射し、粘着剤を硬化させ、粘着力を低下させて、回路面から半導体加工用粘着テープを剥離してもよいが、本実施形態では、半導体加工用粘着テープがリングフレームおよび半導体ウエハに貼り付けられた状態で、ダイシング工程に搬送する。すなわち、半導体加工用粘着テープがバックグラインドテープだけでなく、ダイシングテープも兼ねる。 After grinding the back surface, the adhesive tape for semiconductor processing is irradiated with energy rays, the adhesive is cured, the adhesive force is reduced, and the adhesive tape for semiconductor processing may be peeled off from the circuit surface. The semiconductor processing pressure-sensitive adhesive tape is conveyed to the dicing process in a state where the adhesive tape is attached to the ring frame and the semiconductor wafer. That is, the semiconductor processing adhesive tape serves not only as a back grind tape but also as a dicing tape.
　ダイシング工程では、半導体ウエハを複数の半導体チップに個片化する。個片化する方法としては、公知の方法を採用することができる。たとえば、図２Ｃに示すように、ダイサー等の回転刃８０を用いて半導体ウエハ５０の表面と裏面とを貫通する溝を形成することにより、半導体ウエハ５０を切断して個片化する。個片化された半導体ウエハは半導体チップ５１として得られる。 In the dicing process, the semiconductor wafer is divided into a plurality of semiconductor chips. A known method can be adopted as a method of dividing into individual pieces. For example, as shown in FIG. 2C, by using a rotary blade 80 such as a dicer to form a groove penetrating the front and back surfaces of the semiconductor wafer 50, the semiconductor wafer 50 is cut into individual pieces. The separated semiconductor wafer is obtained as a semiconductor chip 51.
　次に、個片化された半導体ウエハ（すなわち、複数の半導体チップ）から、半導体加工用粘着テープを剥離する。 Next, the semiconductor processing pressure-sensitive adhesive tape is peeled from the singulated semiconductor wafer (that is, a plurality of semiconductor chips).
　まず、粘着テープ１の粘着剤層がエネルギー線硬化性樹脂を含む場合には、図２Ｄに示すように、エネルギー線照射源９０からエネルギー線を照射して粘着剤層を硬化して、粘着剤層の粘着力を低下させる。次いで、図２Ｅに示すように、複数の半導体チップ５１の裏面５１ｂ側およびリングフレーム６０に、ピックアップテープ１００を貼付する。次いで、図２Ｆに示すように、ピックアップテープ１００上に保持された複数の半導体チップ５１から半導体加工用粘着テープを剥離して、半導体チップの回路面５１ａを露出させる。 First, when the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape 1 includes an energy ray curable resin, as shown in FIG. 2D, the pressure-sensitive adhesive layer is cured by irradiating energy rays from an energy ray irradiation source 90. Reduce the adhesion of the layer. Next, as shown in FIG. 2E, the pickup tape 100 is attached to the back surface 51 b side of the plurality of semiconductor chips 51 and the ring frame 60. Next, as shown in FIG. 2F, the semiconductor processing adhesive tape is peeled off from the plurality of semiconductor chips 51 held on the pickup tape 100 to expose the circuit surface 51a of the semiconductor chip.
　その後、ピックアップテープ上にある複数の半導体チップを公知の方法によりピックアップし基板等の上に固定して、半導体装置を製造する。 Thereafter, a plurality of semiconductor chips on the pickup tape are picked up by a known method and fixed on a substrate or the like to manufacture a semiconductor device.
　なお、上記では、半導体ウエハの裏面研削後にダイシング工程を行っているが、いわゆる先ダイシング工程を行ってもよい。具体的には、半導体ウエハの回路形成面（表面）に、ウエハ厚さよりも浅い切込み深さの溝を形成した後、当該回路形成面とリングフレームとに対して、半導体加工用粘着テープを貼付する。そして、上記と同様に、半導体ウエハの裏面研削をすることでウエハの厚みを薄くするとともに、研削面が切り込みまで達することにより半導体ウエハを個片化してもよい。 In the above description, the dicing process is performed after the back surface grinding of the semiconductor wafer, but a so-called first dicing process may be performed. Specifically, after a groove having a depth of cut shallower than the wafer thickness is formed on the circuit forming surface (front surface) of the semiconductor wafer, an adhesive tape for semiconductor processing is applied to the circuit forming surface and the ring frame. To do. Similarly to the above, the thickness of the wafer may be reduced by grinding the back surface of the semiconductor wafer, and the semiconductor wafer may be separated into pieces by reaching the cut surface.
　（４．本実施形態における効果）
　リングフレームと半導体ウエハとが同じ面に貼り付けられる粘着剤層には、半導体ウエハの加工時に求められる特性と、半導体ウエハの加工後に求められる特性とがある。 (4. Effects in the present embodiment)
The pressure-sensitive adhesive layer on which the ring frame and the semiconductor wafer are bonded to the same surface has characteristics required when processing the semiconductor wafer and characteristics required after processing the semiconductor wafer.
　そこで、本実施形態では、半導体ウエハの加工時に求められる特性として、エネルギー線照射前の粘着剤層のゲル分率および損失正接に着目し、これらを特定の範囲内に制御している。一方、半導体ウエハの加工後に求められる特性として、エネルギー線照射後の粘着力に着目し、これを特定の範囲内に制御している。 Therefore, in this embodiment, attention is paid to the gel fraction and loss tangent of the pressure-sensitive adhesive layer before irradiation with energy rays as characteristics required when processing a semiconductor wafer, and these are controlled within a specific range. On the other hand, as a characteristic required after processing a semiconductor wafer, attention is paid to the adhesive force after irradiation with energy rays, and this is controlled within a specific range.
　その結果、本実施形態に係る半導体加工用粘着テープは、半導体ウエハの加工時には弛みが抑制され、半導体ウエハの加工後にリングフレームから当該粘着テープを剥離する際にも良好な剥離性を示すことができる。 As a result, the semiconductor processing pressure-sensitive adhesive tape according to the present embodiment can suppress slack during the processing of the semiconductor wafer, and exhibits good peelability even when the pressure-sensitive adhesive tape is peeled off from the ring frame after the processing of the semiconductor wafer. it can.
　このような特性を実現する粘着剤層の一例として、上述したように、エネルギー線硬化性樹脂と所定の架橋構造とを粘着剤層に存在させている。また、所定の架橋構造は、２種類の架橋剤を用いることにより容易に得ることができる。 As an example of the pressure-sensitive adhesive layer that realizes such characteristics, as described above, the energy ray-curable resin and a predetermined cross-linked structure are present in the pressure-sensitive adhesive layer. The predetermined cross-linked structure can be easily obtained by using two types of cross-linking agents.
　以上、本発明の実施形態について説明してきたが、本発明は上記の実施形態に何ら限定されるものではなく、本発明の範囲内において種々の態様で改変しても良い。 The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications may be made within the scope of the present invention.
　以下、実施例を用いて、発明をより詳細に説明するが、本発明はこれらの実施例に限定されるものではない。 Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.
　本実施例における測定方法および評価方法は以下の通りである。 The measurement method and evaluation method in this example are as follows.
　（ゲル分率）
　表１に示す組成の粘着剤を剥離シート上に塗工、乾燥した。塗工してから７日後の粘着剤を０．３ｇ計量し、♯２００メッシュに包み込んで２３℃条件下で酢酸エチル中に１日間浸漬した。浸漬後メッシュを取り出し、１００℃にて２時間乾燥後、２３℃５０ＲＨの環境下で１時間調湿した後、粘着剤の重量を測定した。ゲル分率（％）は、下記の式から算出した。
（（浸漬前粘着剤重量－浸漬後粘着剤重量）／浸漬前粘着剤重量）×１００ (Gel fraction)
The pressure-sensitive adhesive having the composition shown in Table 1 was coated on a release sheet and dried. Seven days after coating, 0.3 g of the pressure-sensitive adhesive was weighed, wrapped in # 200 mesh, and immersed in ethyl acetate at 23 ° C. for 1 day. After soaking, the mesh was taken out, dried at 100 ° C. for 2 hours, and conditioned at 23 ° C. and 50 RH for 1 hour, and then the weight of the adhesive was measured. The gel fraction (%) was calculated from the following formula.
((Adhesive weight before immersion-Adhesive weight after immersion) / Adhesive weight before immersion) x 100
　また、実施例４および比較例１については、粘着剤からエネルギー線硬化性樹脂を除去した組成の粘着剤を剥離シート上に塗工、乾燥した。塗工してから７日後の粘着剤について、上記と同じ方法によりゲル分率を測定した。 For Example 4 and Comparative Example 1, an adhesive having a composition obtained by removing the energy ray curable resin from the adhesive was coated on a release sheet and dried. About the adhesive 7 days after coating, the gel fraction was measured by the same method as described above.
　（エネルギー線照射後の粘着力）
　粘着力の測定方法を規定するＪＩＳ　Ｚ０２３７に準じ、次の手順により測定した。２３℃、５０ＲＨ％の環境下で、２ｋｇゴムローラーを用いて、粘着シートを被着体であるステンレス鋼（ＳＵＳ３０４）製鏡面板（算術平均粗さＲａ＝０．０５μｍ）に貼付した。５０℃条件下において７日間経過後、リンテック社製紫外線照射装置（ＲＡＤ－２０００ｍ／１２）を用いて、基材側から照度２３０ｍＷ／ｃｍ２、積算光量５００ｍＪ／ｃｍ２の照射条件で紫外線を照射し、粘着剤層を硬化させた。粘着剤層を硬化させた粘着シートを、島津製作所製万能型引張試験機（オートグラフＡＧ－ＩＳ）を用いて剥離角度１８０°、剥離速度３００ｍｍ／ｍｉｎで、ステンレス鋼（ＳＵＳ３０４）製鏡面板から剥離して、粘着力を測定した。得られた値をエネルギー線照射後の粘着力とした。 (Adhesive strength after energy beam irradiation)
According to JIS Z0237 which prescribes the measuring method of adhesive strength, it measured by the following procedure. In an environment of 23 ° C. and 50 RH%, the adhesive sheet was attached to a stainless steel (SUS304) mirror surface plate (arithmetic average roughness Ra = 0.05 μm) using a 2 kg rubber roller. After 7 days under 50 ° C. conditions, UV irradiation was performed from the substrate side under the irradiation conditions of 230 mW / cm 2 illuminance and 500 mJ / cm 2 accumulated light intensity using a Lintec UV irradiation device (RAD-2000m / 12). Then, the pressure-sensitive adhesive layer was cured. The pressure-sensitive adhesive sheet having the cured pressure-sensitive adhesive layer is peeled off from a stainless steel (SUS304) mirror surface plate using a universal tensile tester (Autograph AG-IS) manufactured by Shimadzu Corporation at a peeling angle of 180 ° and a peeling speed of 300 mm / min. It peeled and the adhesive force was measured. The obtained value was defined as the adhesive strength after energy beam irradiation.
　（損失正接）
　粘着剤層 (厚み１０００μｍ)の両面にＰＥＴ系剥離フィルム（リンテック社製：ＳＰ－ＰＥＴ３８１０３１、厚み：３８μｍ）が貼付された積層体を調製した。次に、得られた積層体を８ｍｍφ×３ｍｍの円柱にカットし、損失正接を測定するための試料を得た。粘弾性測定装置(ＴＡ　Ｉｎｓｔｒｕｍｅｎｔｓ社製：ＡＲＥＳ）を使用して、上記の試料に周波数１Ｈｚのひずみを与え、０～１００℃の貯蔵弾性率Ｇ’および損失弾性率Ｇ’’を測定し、それらの値から５０℃における損失正接ｔａｎδを算出した。 (Loss tangent)
A laminate in which a PET release film (manufactured by Lintec: SP-PET 381031, thickness: 38 μm) was attached to both sides of the pressure-sensitive adhesive layer (thickness: 1000 μm) was prepared. Next, the obtained laminate was cut into a cylinder of 8 mmφ × 3 mm to obtain a sample for measuring loss tangent. Using a viscoelasticity measuring device (TA Instruments: ARES), the above sample was strained at a frequency of 1 Hz, and a storage elastic modulus G ′ and a loss elastic modulus G ″ of 0 to 100 ° C. were measured. From this value, the loss tangent tan δ at 50 ° C. was calculated.
　（テープ弛み）
　８インチウエハ用ＳＵＳ３０４製リングフレームと、４インチのシリコンウエハとに、実施例および比較例の半導体加工用粘着テープをＲＡＤ－２７００で貼付した。研削装置に、リングフレームとシリコンウエハとに貼り付けられた半導体加工用粘着テープを載置し、リングフレームを下方に４ｍｍまで押し下げ、半導体加工用粘着テープを伸ばした。その後、リングフレームの押し下げを解除し、５分後に弛みの大きさを測定し、以下の基準でテープの弛みを評価した。
○：弛みなし
△：弛みがあるが実用上問題なし
×：弛みがあり実用上問題あり (Tape slack)
The adhesive tape for semiconductor processing of Examples and Comparative Examples was attached to a ring frame made of SUS304 for 8-inch wafer and a 4-inch silicon wafer with RAD-2700. The semiconductor processing adhesive tape affixed to the ring frame and the silicon wafer was placed on the grinding apparatus, the ring frame was pushed down to 4 mm downward, and the semiconductor processing adhesive tape was extended. Thereafter, the ring frame was released from depression, and the size of the slack was measured after 5 minutes, and the slack of the tape was evaluated according to the following criteria.
○: No slack △: There is slack but there is no practical problem ×: There is slack and there is practical problem
　（リングフレームからの剥離）
　次に、リングフレームを押し下げた状態で、シリコンウエハを仕上げ厚１５０μｍとなるように研削した。研削後、リングフレームの高さを元に戻し、紫外線照射（照度：２３０ｍＷ／ｃｍ２、光量：１９０ｍＪ／ｃｍ２）を行ったのち、半導体加工用粘着テープをリングフレームから剥離し、リングフレームからの剥離状態を以下の基準で評価した。
○：剥離不良無し
△：剥離不良発生 (重剥離化)
×：剥離不良発生 (リングフレームへテープが固着) (Peeling from the ring frame)
Next, the silicon wafer was ground to a finished thickness of 150 μm with the ring frame pressed down. After grinding, the ring frame is returned to its original height, irradiated with ultraviolet rays (illuminance: 230 mW / cm 2 , light intensity: 190 mJ / cm 2 ), and then the semiconductor processing adhesive tape is peeled off from the ring frame. The peeled state was evaluated according to the following criteria.
○: No peeling failure △: Generation of peeling failure (heavy peeling)
×: Peeling failure occurred (tape stuck to the ring frame)
　（実施例１）
　（粘着剤組成物の調製）
　ブチルアクリレート（ＢＡ）９１質量部と、アクリル酸（ＡＡ）９質量部とを共重合し、官能基含有アクリル系共重合体（重量平均分子量：７０万）を得た。得られたアクリル系重共重合体１００質量部（固形分換算、以下同じ）と、トリレンジイソシアネート系架橋剤（トーソー社製，製品名「コロネートＬ」）９質量部と、ポリグリシジルアミン系化合物（三菱ガス化学社製，ＴＥＴＲＡＤ－Ｃ）０．０４５質量部と、多官能型ウレタンアクリレートオリゴマーＡ（セイカビームＥＸＬ－８１０ＴＬ：Ｍｗ＝５０００）１２７質量部と、多官能型ウレタンアクリレートオリゴマーＢ（シコウＵＶ－５８０６：Ｍｗ＝１７４０）４０質量部と、を溶媒としてのメチルエチルケトン中で混合し、固形分の含有量が３５質量％である粘着剤組成物を得た。 (Example 1)
(Preparation of adhesive composition)
91 parts by mass of butyl acrylate (BA) and 9 parts by mass of acrylic acid (AA) were copolymerized to obtain a functional group-containing acrylic copolymer (weight average molecular weight: 700,000). 100 parts by mass of the resulting acrylic heavy copolymer (in terms of solid content, the same applies hereinafter), 9 parts by mass of tolylene diisocyanate crosslinking agent (product name “Coronate L” manufactured by Tosoh Corporation), and polyglycidylamine compound 0.045 parts by mass (Mitsubishi Gas Chemical Co., Ltd., TETRAD-C), 127 parts by mass of polyfunctional urethane acrylate oligomer A (Seika Beam EXL-810TL: Mw = 5000), and polyfunctional urethane acrylate oligomer B (Shiko UV) −5806: Mw = 1740) 40 parts by mass in methyl ethyl ketone as a solvent was obtained to obtain a pressure-sensitive adhesive composition having a solid content of 35% by mass.
　（半導体加工用粘着テープの製造）
　剥離シート（リンテック社製，ＳＰ－ＰＥＴ３８１０３１）の剥離面上に、上記の粘着剤組成物を塗布した。次いで、加熱による乾燥を行い、架橋反応を進行させ、粘着剤組成物の塗膜を粘着剤層とした。この粘着剤層の厚さは１５μｍであった。その後、得られた剥離シート上の粘着剤層と、基材として一方の面がコロナ処理されたエチレン－メタクリル酸共重合体（ＥＭＡＡ）フィルム（厚さ：８０μｍ）のコロナ処理面とを貼合することで、半導体加工用粘着テープを得た。 (Manufacture of adhesive tape for semiconductor processing)
The above-mentioned pressure-sensitive adhesive composition was applied on the release surface of a release sheet (SP-PET 381031 manufactured by Lintec Corporation). Subsequently, drying by heating was performed to advance the crosslinking reaction, and the coating film of the pressure-sensitive adhesive composition was used as a pressure-sensitive adhesive layer. The thickness of the pressure-sensitive adhesive layer was 15 μm. Thereafter, the pressure-sensitive adhesive layer on the obtained release sheet was bonded to the corona-treated surface of an ethylene-methacrylic acid copolymer (EMAA) film (thickness: 80 μm) having a corona-treated one surface as a base material. Thus, an adhesive tape for semiconductor processing was obtained.
　（実施例２～５、比較例１および２）
　粘着剤の組成を表１に示す組成とした以外は、 実施例１と同じ方法により、半導体加工用粘着テープを得た。 (Examples 2 to 5, Comparative Examples 1 and 2)
A semiconductor processing adhesive tape was obtained in the same manner as in Example 1 except that the composition of the adhesive was changed to the composition shown in Table 1.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　得られた試料（実施例１～５、比較例１および２）に対して、上記の測定および評価を行った。結果を表２に示す。なお、実施例１において、粘着剤からエネルギー線硬化性樹脂を除去した組成の粘着剤のゲル分率は７５％であり、実施例４において、粘着剤からエネルギー線硬化性樹脂を除去した組成の粘着剤のゲル分率は８５％であった。また、比較例１において、粘着剤からエネルギー線硬化性樹脂を除去した組成の粘着剤のゲル分率は５５％であった。 The above measurements and evaluations were performed on the obtained samples (Examples 1 to 5, Comparative Examples 1 and 2). The results are shown in Table 2. In Example 1, the gel fraction of the composition obtained by removing the energy ray curable resin from the adhesive is 75%. In Example 4, the composition of the composition obtained by removing the energy ray curable resin from the adhesive. The gel fraction of the pressure-sensitive adhesive was 85%. Moreover, in the comparative example 1, the gel fraction of the adhesive of the composition which removed the energy beam curable resin from the adhesive was 55%.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　表２より、ゲル分率および損失正接が上述した範囲内である場合には、テープの弛みが良好であることが確認できた。また、紫外線照射後の粘着力が上述した範囲内である場合には、リングフレームからの剥離性が良好であることが確認できた。 From Table 2, when the gel fraction and loss tangent are within the above-mentioned ranges, it was confirmed that the tape was slack. Moreover, when the adhesive force after ultraviolet irradiation was in the range mentioned above, it has confirmed that the peelability from a ring frame was favorable.
　また、実施例１および４より、架橋構造のゲル分率は、粘着剤層のゲル分率よりも非常に高いことが確認できた。すなわち、実施例に係る半導体加工用粘着テープの粘着剤層には、見掛けのゲル分率よりも強く架橋した架橋構造が存在することが確認できた。 Further, from Examples 1 and 4, it was confirmed that the gel fraction of the crosslinked structure was much higher than the gel fraction of the pressure-sensitive adhesive layer. That is, it was confirmed that the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape for semiconductor processing according to the example had a cross-linked structure that was cross-linked more strongly than the apparent gel fraction.
　本発明の半導体加工用粘着テープは、たとえば、リングフレームと半導体ウエハとに貼り付けられた状態での半導体ウエハの加工に好適に使用することができる。 The adhesive tape for semiconductor processing of the present invention can be suitably used, for example, for processing a semiconductor wafer in a state of being attached to a ring frame and a semiconductor wafer.
１…粘着シート
　１０…基材
　２０…粘着剤層 DESCRIPTION OF SYMBOLS 1 ... Adhesive sheet 10 ... Base material 20 ... Adhesive layer

Claims (5)

  1. 　基材と、基材の一方の面側に設けられた粘着剤層とを有する粘着テープであって、
    　前記粘着剤層に対するエネルギー線照射前において、前記粘着剤層のゲル分率が３５％以上であり、５０℃における前記粘着剤層の損失正接が０．６５未満であり、
    　前記粘着剤層に対するエネルギー線照射後において、前記粘着剤層の粘着力が３１００ｍＮ／２５ｍｍ以下であることを特徴とする半導体加工用粘着テープ。     A pressure-sensitive adhesive tape having a base material and a pressure-sensitive adhesive layer provided on one surface side of the base material,
    Before the energy ray irradiation to the pressure-sensitive adhesive layer, the gel fraction of the pressure-sensitive adhesive layer is 35% or more, and the loss tangent of the pressure-sensitive adhesive layer at 50 ° C. is less than 0.65,
    The adhesive tape for semiconductor processing, wherein an adhesive force of the adhesive layer is 3100 mN / 25 mm or less after energy beam irradiation to the adhesive layer.
  2. 　前記粘着剤層が架橋構造とエネルギー線硬化性樹脂とを有することを特徴とする請求項１に記載の半導体加工用粘着テープ。 2. The semiconductor processing pressure-sensitive adhesive tape according to claim 1, wherein the pressure-sensitive adhesive layer has a crosslinked structure and an energy ray curable resin.
  3. 　前記架橋構造は、少なくともアクリル系重合体と架橋剤とから構成されることを特徴とする請求項２に記載の半導体加工用粘着テープ。 3. The pressure-sensitive adhesive tape for semiconductor processing according to claim 2, wherein the crosslinked structure is composed of at least an acrylic polymer and a crosslinking agent.
  4. 　前記架橋構造のゲル分率が７０％以上９５％以下であることを特徴とする請求項３に記載の半導体加工用粘着テープ。 The adhesive tape for semiconductor processing according to claim 3, wherein the gel fraction of the crosslinked structure is 70% or more and 95% or less.
  5. 　半導体ウエハを加工する工程において、加工装置に固定されるリングフレームと前記半導体ウエハとが前記粘着剤層に貼付されることを特徴とする請求項１から４のいずれかに記載の半導体加工用粘着テープ。 5. The semiconductor processing adhesive according to claim 1, wherein in the step of processing a semiconductor wafer, a ring frame fixed to a processing apparatus and the semiconductor wafer are attached to the adhesive layer. tape.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7205596B1 (en) 2021-09-30 2023-01-17 住友ベークライト株式会社 Adhesive tape
JP7226501B1 (en) 2021-09-30 2023-02-21 住友ベークライト株式会社 Adhesive tapes and substrates for adhesive tapes

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007048920A (en) * 2005-08-10 2007-02-22 Renesas Technology Corp Method of manufacturing semiconductor device
JP2008027960A (en) * 2006-07-18 2008-02-07 Nitto Denko Corp Heat-resistance dicing tape or sheet
JP2009064975A (en) * 2007-09-06 2009-03-26 Nitto Denko Corp Dicing adhesive sheet and dicing method
JP2011122100A (en) * 2009-12-11 2011-06-23 Lintec Corp Adhesive sheet for processing electronic part
JP2016225389A (en) * 2015-05-28 2016-12-28 日東電工株式会社 Back grind tape

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3325650B2 (en) 1993-04-15 2002-09-17 株式会社ディスコ Wafer polishing method
JP3620810B2 (en) * 1996-05-02 2005-02-16 リンテック株式会社 Wafer protection adhesive sheet
JP3602943B2 (en) 1997-07-25 2004-12-15 シャープ株式会社 Semiconductor wafer grinding machine
JP5049612B2 (en) * 2007-02-28 2012-10-17 リンテック株式会社 Adhesive sheet
WO2016139840A1 (en) * 2015-03-02 2016-09-09 リンテック株式会社 Dicing sheet and method for manufacturing semiconductor chip

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007048920A (en) * 2005-08-10 2007-02-22 Renesas Technology Corp Method of manufacturing semiconductor device
JP2008027960A (en) * 2006-07-18 2008-02-07 Nitto Denko Corp Heat-resistance dicing tape or sheet
JP2009064975A (en) * 2007-09-06 2009-03-26 Nitto Denko Corp Dicing adhesive sheet and dicing method
JP2011122100A (en) * 2009-12-11 2011-06-23 Lintec Corp Adhesive sheet for processing electronic part
JP2016225389A (en) * 2015-05-28 2016-12-28 日東電工株式会社 Back grind tape

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7205596B1 (en) 2021-09-30 2023-01-17 住友ベークライト株式会社 Adhesive tape
JP7226501B1 (en) 2021-09-30 2023-02-21 住友ベークライト株式会社 Adhesive tapes and substrates for adhesive tapes
JP2023051587A (en) * 2021-09-30 2023-04-11 住友ベークライト株式会社 Adhesive tape and base material for adhesive tape
JP2023051588A (en) * 2021-09-30 2023-04-11 住友ベークライト株式会社 Adhesive tape

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