WO2022123932A1 - Adhesive sheet - Google Patents

Adhesive sheet Download PDF

Info

Publication number
WO2022123932A1
WO2022123932A1 PCT/JP2021/039065 JP2021039065W WO2022123932A1 WO 2022123932 A1 WO2022123932 A1 WO 2022123932A1 JP 2021039065 W JP2021039065 W JP 2021039065W WO 2022123932 A1 WO2022123932 A1 WO 2022123932A1
Authority
WO
WIPO (PCT)
Prior art keywords
pressure
sensitive adhesive
adhesive layer
adhesive sheet
resin
Prior art date
Application number
PCT/JP2021/039065
Other languages
French (fr)
Japanese (ja)
Inventor
拓三 由藤
和通 加藤
航大 中尾
Original Assignee
日東電工株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日東電工株式会社 filed Critical 日東電工株式会社
Priority to KR1020237011454A priority Critical patent/KR20230061511A/en
Priority to CN202180069545.6A priority patent/CN116368199A/en
Priority to JP2022568091A priority patent/JPWO2022123932A1/ja
Priority to DE112021005267.5T priority patent/DE112021005267T5/en
Publication of WO2022123932A1 publication Critical patent/WO2022123932A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/50—Assembly of semiconductor devices using processes or apparatus not provided for in a single one of the subgroups H01L21/06 - H01L21/326, e.g. sealing of a cap to a base of a container
    • H01L21/56—Encapsulations, e.g. encapsulation layers, coatings
    • H01L21/568—Temporary substrate used as encapsulation process aid
    • 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]
    • C09J7/381—Pressure-sensitive adhesives [PSA] based on macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
    • C09J7/385—Acrylic polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/10—Esters
    • C08F220/12—Esters of monohydric alcohols or phenols
    • C08F220/16—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms
    • C08F220/18—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms with acrylic or methacrylic acids
    • C08F220/1802—C2-(meth)acrylate, e.g. ethyl (meth)acrylate
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/10—Esters
    • C08F220/12—Esters of monohydric alcohols or phenols
    • C08F220/16—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms
    • C08F220/18—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms with acrylic or methacrylic acids
    • C08F220/1808—C8-(meth)acrylate, e.g. isooctyl (meth)acrylate or 2-ethylhexyl (meth)acrylate
    • 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
    • C09J133/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical
    • C09J133/08—Homopolymers or copolymers of acrylic acid esters
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/50—Assembly of semiconductor devices using processes or apparatus not provided for in a single one of the subgroups H01L21/06 - H01L21/326, e.g. sealing of a cap to a base of a container
    • H01L21/56—Encapsulations, e.g. encapsulation layers, coatings
    • 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
    • C09J2301/10—Additional features of adhesives in the form of films or foils characterized by the structural features of the adhesive tape or sheet
    • C09J2301/12—Additional features of adhesives in the form of films or foils characterized by the structural features of the adhesive tape or sheet by the arrangement of layers
    • C09J2301/124—Additional features of adhesives in the form of films or foils characterized by the structural features of the adhesive tape or sheet by the arrangement of layers the adhesive layer being present on both sides of the carrier, e.g. double-sided adhesive tape
    • 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
    • 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
    • C09J2433/00—Presence of (meth)acrylic polymer

Definitions

  • the present invention relates to an adhesive sheet.
  • the semiconductor chips may be resin-sealed in order to prevent damage to the semiconductor chips, expand metal wiring, and the like.
  • the semiconductor chip may be resin-sealed on the pressure-sensitive adhesive sheet from the viewpoint of workability and the like.
  • a plurality of semiconductor chips are arranged on an adhesive sheet as a predetermined temporary fixing material, and the semiconductor chips are collectively sealed on the adhesive sheet.
  • the pressure-sensitive adhesive sheet is peeled off from the resin encapsulating the semiconductor chip.
  • the present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to have an appropriate adhesiveness to a sealing resin for encapsulating a semiconductor chip and a semiconductor chip, and the sealing thereof.
  • an adhesive sheet that can be easily peeled off from the stop resin does not easily leave adhesive residue during peeling, and does not easily cause a step between the semiconductor chip and the sealing resin after the adhesive sheet is peeled off. be.
  • the pressure-sensitive adhesive sheet of the present invention is a pressure-sensitive adhesive sheet including a base material and a pressure-sensitive adhesive layer arranged on at least one side of the base material, wherein the pressure-sensitive adhesive layer contains an acrylic pressure-sensitive adhesive, and the pressure-sensitive adhesive sheet is used.
  • the amount of subduction under the environment of 23 ° C. using TMA is 5 ⁇ m or less, and the T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is 45 ⁇ sec or less.
  • the rate of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is 160% or less.
  • the amount of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is 20 ⁇ m or less.
  • the pressure-sensitive adhesive layer comprises a pressure-sensitive adhesive, wherein the pressure-sensitive adhesive has a sp value of 18 (cal / cm 3 ) 1/2 to 20 (cal / cm 3 ) 1/2 . including.
  • the acrylic pressure-sensitive adhesive comprises a crosslinked body of the acrylic polymer as a base polymer.
  • the acrylic pressure-sensitive adhesive comprises an epoxy-based cross-linking agent.
  • the blending amount of the epoxy-based cross-linking agent is 0.6 parts by weight to 15 parts by weight with respect to 100 parts by weight of the acrylic polymer.
  • the substrate is a resin sheet composed of a resin having a glass transition temperature (Tg) of 25 ° C. or higher.
  • Tg glass transition temperature
  • the thickness of the substrate is 20% to 90% with respect to the total thickness of the pressure-sensitive adhesive sheet.
  • the amount of subduction of the pressure-sensitive adhesive sheet in an environment of 145 ° C. using TMA is 1 ⁇ m to 35 ⁇ m.
  • the amount of nitrogen gas generated when the pressure-sensitive adhesive layer is heat-treated is 0.06% by weight to 1% by weight.
  • the pressure-sensitive adhesive sheet is a second base material, a pressure-sensitive adhesive layer arranged on one side of the base material, and a second surface of the base material opposite to the pressure-sensitive adhesive layer. Provided with a pressure-sensitive adhesive layer.
  • the pressure-sensitive adhesive sheet is a temporary fixing material used in the resin sealing step of a semiconductor chip. In one embodiment, the pressure-sensitive adhesive sheet is used to cure the sealing resin on the pressure-sensitive adhesive sheet.
  • the present invention has an appropriate adhesiveness to the encapsulating resin for encapsulating a semiconductor chip and the semiconductor chip, can be easily peeled from the encapsulating resin, and is unlikely to leave adhesive residue during peeling. Moreover, it is possible to provide an adhesive sheet that does not easily cause a step between the semiconductor chip and the sealing resin after the adhesive sheet is peeled off.
  • FIG. 3 is a schematic cross-sectional view of an adhesive sheet according to another embodiment of the present invention.
  • FIG. 1 of the pressure-sensitive adhesive sheet is a schematic cross-sectional view of the pressure-sensitive adhesive sheet according to one embodiment of the present invention.
  • the pressure-sensitive adhesive sheet 100 includes a base material 10 and a pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer) 20 arranged on at least one side of the base material 10.
  • the pressure-sensitive adhesive layer contains an acrylic pressure-sensitive adhesive.
  • the pressure-sensitive adhesive sheet of the present invention can be suitably used as a temporary fixing material when sealing a semiconductor chip with a resin. More specifically, in the pressure-sensitive adhesive sheet of the present invention, semiconductor chips are arranged on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, the semiconductor chips are covered with a resin (usually an epoxy resin), and the sealing resin is cured. Can be used as a temporary fixing material for the semiconductor chip when the semiconductor chip is resin-sealed. After the semiconductor chip is resin-sealed, the pressure-sensitive adhesive sheet is a sealing resin and a semiconductor during a predetermined post-process (for example, backside grinding of the sealing resin, pattern formation, bump formation, chip formation (cutting)). It can be peeled off from the structure composed of the chip.
  • the epoxy equivalent of the sealing resin is, for example, 50 g / eq to 500 g / eq.
  • the amount of subduction of the pressure-sensitive adhesive sheet in an environment of 23 ° C. using TMA is 5 ⁇ m or less. Further, the T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is 45 ⁇ sec or less. According to the pressure-sensitive adhesive sheet having these characteristics, when the semiconductor chip is resin-sealed on the pressure-sensitive adhesive sheet and then the pressure-sensitive adhesive sheet is peeled off, the generation of a step between the semiconductor chip and the sealing resin is prevented.
  • FIG. 2A shows an example of the case where the conventional pressure-sensitive adhesive sheet 100'is used for resin encapsulation of a semiconductor chip.
  • the pressure-sensitive adhesive sheet 100' has a pressure-sensitive adhesive layer, and the outer surface of the pressure-sensitive adhesive layer is used as a sticking surface.
  • the semiconductor chip is resin-sealed, the semiconductor chip 1 is first attached to the pressure-sensitive adhesive sheet 100'(ai).
  • composition 2'containing the monomer which is the precursor of the sealing resin 2 is applied (a-ii) so as to seal the semiconductor chip 1, and then the composition 2'is cured (a). -Iii).
  • a composition containing a naphthalene-type bifunctional epoxy resin epoxy equivalent: 144.
  • the pressure-sensitive adhesive sheet 100' is peeled off from the structure A containing the semiconductor chip 1 and the sealing resin 2 during a predetermined post-process (a-iv).
  • a mixed phase with the sealing resin component is formed. If the mixed phase is formed, when the pressure-sensitive adhesive sheet is peeled off, the mixed phase is destroyed and a part of the sealing resin is peeled off together with the pressure-sensitive adhesive sheet, resulting in a step between the semiconductor chip and the sealing resin. Occurs.
  • a part of the semiconductor chip is embedded in the pressure-sensitive adhesive layer due to the force applied to the semiconductor chip.
  • the embedding of the pressure-sensitive adhesive layer of the semiconductor chip also causes a step difference between the semiconductor chip and the sealing resin.
  • the pressure-sensitive adhesive layer component is transferred to the sealing resin and the semiconductor chip is embedded in the pressure-sensitive adhesive layer (particularly). (Embedding of the semiconductor chip into the pressure-sensitive adhesive layer) can be prevented (FIG. 2 (b)). Further, by setting the T 2 relaxation time (T 2s ) of the S component of the pressure-sensitive adhesive layer by pulse NMR to 45 ⁇ sec or less, the pressure-sensitive adhesive layer component is transferred to the sealing resin and the semiconductor chip is embedded in the pressure-sensitive adhesive layer. (In particular, the transfer of the pressure-sensitive adhesive layer component to the sealing resin) can be prevented (FIG. 2 (b)).
  • the amount of subduction of the pressure-sensitive adhesive sheet in an environment of 23 ° C. using TMA is preferably 4 ⁇ m or less, more preferably 3.5 ⁇ m, and further preferably 3 ⁇ m or less. Within such a range, the effect of the present invention becomes remarkable.
  • the sinking amount can be set within the above range.
  • the "subduction amount of the adhesive sheet in a 23 ° C environment using TMA" is determined after 60 minutes have passed by bringing the probe into contact with the adhesive layer (first adhesive layer) using a thermomechanical analyzer. Means the amount of subduction.
  • the measurement conditions are probe: needle insertion, nitrogen gas flow rate: 50.0 ml / min, and indentation load: 0.01 N.
  • the standard pressure-sensitive adhesive layer is an acrylic copolymer (2-ethylhexyl acrylate (2EHA), ethyl acrylate (EA), methyl methacrylate (MMA) and 2-hydroxyethyl acrylate (HEA) copolymer, 2EHA constituent unit: EA constituent unit: MMA.
  • the amount of subduction of the pressure-sensitive adhesive sheet in an environment of 145 ° C. using TMA is preferably 1 ⁇ m to 35 ⁇ m, more preferably 1 ⁇ m to 34 ⁇ m, and further preferably 2 ⁇ m to 34 ⁇ m. Within such a range, the effect of the present invention becomes remarkable. Further, even when subjected to a high temperature environment (for example, a heat treatment environment at the time of resin encapsulation), embedding of the semiconductor chip in the pressure-sensitive adhesive layer is prevented.
  • FIG. 3 is a schematic cross-sectional view of an adhesive sheet according to another embodiment of the present invention.
  • the pressure-sensitive adhesive sheet 200 further includes a second pressure-sensitive adhesive layer 30 on the side opposite to the pressure-sensitive adhesive layer 20 of the base material 10. That is, the pressure-sensitive adhesive sheet 200 includes a pressure-sensitive adhesive layer 20, a base material 10, and a second pressure-sensitive adhesive layer 30 in this order.
  • the second pressure-sensitive adhesive layer 30 By providing the second pressure-sensitive adhesive layer 30, when the resin is sealed on the pedestal, the second pressure-sensitive adhesive layer 30 side is attached to the pedestal, and the pressure-sensitive adhesive sheet 200 is arranged with good fixing property. Can be done.
  • the second pressure-sensitive adhesive layer comprises thermally expandable microspheres.
  • the thermally expandable microspheres can expand at a predetermined temperature.
  • the heat-expandable microspheres expand by heating to a predetermined temperature or higher, and the adhesive surface (that is, the surface of the second pressure-sensitive adhesive layer) becomes uneven. Adhesive strength decreases or disappears.
  • the necessary adhesiveness is exhibited when the pressure-sensitive adhesive sheet is fixed (for example, fixed to a pedestal), and when the pressure-sensitive adhesive sheet is peeled off (for example, for example). When peeling from the pedestal), the adhesive strength is reduced or disappears by heating, and good peelability is exhibited.
  • the pressure-sensitive adhesive force A at 23 ° C. when the pressure-sensitive adhesive layer is attached to polyethylene terephthalate is preferably 0.05 N / 20 mm to 1 N / 20 mm, more preferably 0.1 N / 20 mm to. It is 10N / 20mm, more preferably 0.1N / 20mm to 5N / 20mm, particularly preferably 0.2N / 20mm to 2N / 20mm, and most preferably 0.2N / 20mm to 1N / 20mm. .. Within such a range, an adherend (for example, a semiconductor chip) can be preferably fixed, and a pressure-sensitive adhesive sheet having less adhesive residue at the time of peeling can be obtained.
  • an adherend for example, a semiconductor chip
  • adheresive strength at 23 ° C. when the adhesive layer is attached to polyethylene terephthalate means that an adhesive sheet (width 20 mm x length 140 mm) is adhered to a polyethylene terephthalate film (thickness 25 ⁇ m).
  • the agent layers are bonded (bonding conditions: 1 reciprocation of a 2 kg roller), left at an environmental temperature of 23 ° C. for 30 minutes, and then the sample is subjected to a tensile test (peeling speed: 300 mm / min, peeling angle 180 °). Adhesive strength to be measured.
  • the shear adhesive force B at 150 ° C. when the silicon chip is attached to the pressure-sensitive adhesive layer is preferably 500 g or more, more preferably 700 g to 1500 g, and further preferably 800 g to 1200 g. Is.
  • the adhesive has a high cohesive force, has a preferable adhesive force even at a high temperature (for example, a heating step for curing the sealing resin), and is arranged on the adhesive sheet. It is possible to prevent the displacement of the adherend (for example, a semiconductor chip).
  • the mirror surface of the silicon chip (size: 5 mm x 5 mm) is attached vertically to the adhesive layer so that the tip angle does not hit, and then heated at 130 ° C. for 30 minutes to adhere to the surface of the silicon chip adhesive. Then, the maximum breaking load is read from the load-displacement curve obtained by applying an external force horizontally to the chip at a shear rate of 500 ⁇ m / sec under the measured temperature (150 ° C in the case of shear adhesive force B measurement). This can be measured.
  • the measuring device for example, a Dage 4000 manufactured by Nordson is used. Further, the measurement terminal at the time of the above measurement may be located at a height of 250 ⁇ m on the surface of the pressure-sensitive adhesive layer.
  • the pressure-sensitive adhesive sheet of the present invention has a shear adhesive force at 190 ° C. when the silicon chip is attached to the pressure-sensitive adhesive layer, preferably 300 g to 1000 g, more preferably 350 g to 750 g, and further preferably 400 g to 600 g. Is.
  • the pressure-sensitive adhesive sheet includes a second pressure-sensitive adhesive layer containing heat-expandable microspheres
  • the second pressure-sensitive adhesive layer side exhibits peelability, that is, the said.
  • the adherend on the pressure-sensitive adhesive layer can be preferably fixed.
  • the thickness of the pressure-sensitive adhesive sheet of the present invention is preferably 3 ⁇ m to 300 ⁇ m, more preferably 5 ⁇ m to 150 ⁇ m, and further preferably 10 ⁇ m to 100 ⁇ m.
  • the adhesive layer is composed of an adhesive containing a base polymer.
  • T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is 45 ⁇ sec or less.
  • the relaxation time means the time until the excited atom (group) returns to the ground state after irradiating the atom with appropriate energy to excite the atom to be measured in the pulse NMR measurement.
  • the excited state of an atom (group) can be controlled by the amount and time of energy irradiation. It is also known that there are various energy relaxation mechanisms for excited atoms (groups) to return to the ground state, and the relaxation time is determined according to the relaxation mechanism (for example, for chemists).
  • the inventors excited the 1H atom of the acrylic pressure - sensitive adhesive (substantially, the acrylic-based polymer contained in the pressure-sensitive adhesive) under the following conditions, measured the subsequent relaxation behavior, and further analyzed the measured values.
  • the S component of the T 2 relaxation time is used as information for knowing the molecular motion related to the degree of cross-linking of the base polymer (typically, an acrylic polymer) contained in the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer. It was found that (T 2s ) is useful, and that the above effect can be obtained by specifying the S component (T 2s ) of the T 2 relaxation time.
  • a short T 2s indicates that the molecular motion related to the degree of cross-linking of the base polymer is restricted, that is, the cross-linking progresses and the degree of freedom of motion of the polymer as a whole is reduced. Is shown.
  • the gap between the base polymers is small, and the pressure-sensitive adhesive layer component is transferred to the sealing resin and the low molecular weight component contained in the sealing resin is transferred to the pressure-sensitive adhesive layer. Is suppressed.
  • the semiconductor chip is resin-sealed on the pressure-sensitive adhesive sheet and then the pressure-sensitive adhesive sheet is peeled off, the generation of a step between the semiconductor chip and the sealing resin is prevented.
  • the T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is preferably 10 ⁇ sec to 50 ⁇ sec, more preferably 10 ⁇ sec to 45 ⁇ sec, and further preferably 10 ⁇ sec to 40 ⁇ sec. Within such a range, the above effect becomes remarkable.
  • T 2 relaxation time (T 2s ) of the S component by pulse NMR a T 2 relaxation curve measured by the solid echo method was obtained using 100 mg of the pressure-sensitive adhesive layer as a measurement sample, and the T 2 relaxation curve was calculated by the following equation (1). You can find it by fitting it to.
  • M (t) ⁇ ⁇ exp (-(1 / Wa) (t / T 2s ) Wa ) + ⁇ ⁇ exp (-(1 / Wa) (t / T 2L ) Wa ) ⁇ ⁇ ⁇ (1)
  • M (t): Free induction decay ⁇ : Proton ratio (%) of component (S component) with short relaxation time T 2s : T 2 relaxation time (msec) of S component ⁇ : Proton ratio (%) of the component (L component) with a long relaxation time T 2L : T 2 relaxation time (msec) of L component t: Observation time (msec) Wa: Shape coefficient ( 1)
  • the measurement conditions in the above measurement are as follows. 90 ° pulse width: 2.1 ⁇ sec ⁇ Repeat time: 1 sec ⁇ Number of integrations: 32 times ⁇ Measurement temperature: 30 ° C
  • the rate of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is preferably 160% or less, more preferably 150% or less. It is more preferably 120% or less, and particularly preferably 100% or less.
  • the pressure-sensitive adhesive layer having a thickness change rate in such a range has a high crosslink density and prevents component transfer between the pressure-sensitive adhesive layer and the sealing resin, and as a result, after the semiconductor chip is resin-sealed on the pressure-sensitive adhesive sheet. When the adhesive sheet is peeled off, the generation of a step between the semiconductor chip and the sealing resin is prevented.
  • the thickness change rate (and the thickness change amount described later) can be set in the above range by preferably selecting, for example, a base polymer (typically, an acrylic polymer) contained in an acrylic pressure-sensitive adhesive. ..
  • a base polymer typically, an acrylic polymer
  • an acrylic polymer having a large number of carbon atoms for example, 4 or more, preferably 8 or more
  • a pressure-sensitive adhesive layer having a small thickness change rate (and a thickness change amount described later) can be formed.
  • the thickness change rate is as follows: 4-tertiary butylphenylglycidyl ether is added dropwise to the surface of the pressure-sensitive adhesive layer in a predetermined amount (0.02 g using a syringe having a diameter of 22 mm) at 23 ° C. and 50% RH for 1 minute. From the thickness (Dt) of the dropping point after leaving and wiping off the 4-tertiary butylphenylglycidyl ether and the thickness (It) of the dropping point before the dropping operation, (Dt-It) / It It is calculated by the formula.
  • the amount of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is preferably 20 ⁇ m or less, more preferably 15 ⁇ m or less. It is more preferably 10 ⁇ m or less, and particularly preferably 6 ⁇ m or less.
  • the pressure-sensitive adhesive layer having a thickness change in such a range has a high crosslink density and prevents component transfer between the pressure-sensitive adhesive layer and the sealing resin, and as a result, after the semiconductor chip is resin-sealed on the pressure-sensitive adhesive sheet. When the adhesive sheet is peeled off, the generation of a step between the semiconductor chip and the sealing resin is prevented.
  • the smaller the thickness change amount, the more preferable, but the lower limit thereof is, for example, 3 ⁇ m (preferably 1 ⁇ m).
  • the thickness change amount is obtained from the above Dt and It by the formula of Dt-It.
  • the gel fraction of the pressure-sensitive adhesive layer is preferably 75% or more, more preferably 85% or more, and further preferably 90% or more. Within such a range, the molecular motion of the base polymer is preferably restricted by cross-linking, and a pressure-sensitive adhesive layer in which component transfer between the pressure-sensitive adhesive layer and the sealing resin is prevented can be obtained.
  • the gel fraction is determined by immersing the crosslinked pressure-sensitive adhesive in ethyl acetate for 7 days and then drying it (dry weight after immersion / dry weight before immersion) ⁇ 100.
  • the amount of nitrogen gas generated when the pressure-sensitive adhesive layer is heat-treated is preferably 0.06% by weight to 1.0% by weight, and more preferably 0.06% by weight to 0.9% by weight.
  • the acrylic pressure-sensitive adhesive exhibits sufficient cohesive power, and the low-molecular-weight component of the sealing resin is applied to the pressure-sensitive adhesive layer.
  • the thickness of the pressure-sensitive adhesive layer is preferably 1 ⁇ m to 50 ⁇ m, more preferably 3 ⁇ m to 30 ⁇ m, and further preferably 5 ⁇ m to 20 ⁇ m. Within such a range, it is possible to obtain an adhesive sheet that is difficult to embed in the resin of the semiconductor chip even by pressurization during the sealing step.
  • the elastic modulus of the pressure-sensitive adhesive layer at 25 ° C. by the nanoindentation method is preferably less than 100 MPa, more preferably 0.1 MPa to 50 MPa, and further preferably 0.1 MPa to 10 MPa. Within such a range, an adhesive sheet having an appropriate adhesive strength can be obtained.
  • the elastic modulus by the nanoindentation method is the load load-pushing depth obtained by continuously measuring the load on the indenter and the pushing depth when the indenter is pushed into the sample during loading and unloading.
  • the elastic modulus obtained from the curve In the present specification, the elastic modulus by the nanoindentation method means the elastic modulus measured as described above under the measurement conditions of load: 1 mN, load / unloading speed: 0.1 mN / s, and holding time: 1s.
  • the tensile elastic modulus of the pressure-sensitive adhesive layer at 25 ° C. is preferably less than 100 MPa, more preferably 0.1 MPa to 50 MPa, and further preferably 0.1 MPa to 10 MPa. Within such a range, an adhesive sheet having an appropriate adhesive strength can be obtained.
  • the tensile elastic modulus can be measured according to JIS K 7161: 2008.
  • the probe tack value of the pressure-sensitive adhesive layer is preferably 50 N / 5 mm ⁇ or more, more preferably 75 N / 5 mm ⁇ or more, and further preferably 100 N / 5 mm ⁇ or more. Within such a range, it is possible to prevent misalignment of the adherend (for example, a semiconductor chip) arranged on the adhesive sheet.
  • the measurement conditions for the probe tack value are: probe processing speed: 30 mm / min, test speed: 30 mm / min, adhesion load: 100 gf, adhesion holding time: 1 second, probe area: 5 mm ⁇ SUS.
  • the sp value of the base polymer is preferably 10 (cal / cm 3 ) 1/2 to 30 (cal / cm 3 ) 1/2 , and more preferably 15 (cal / cm 3 ) 1/2 to 25 ( It is cal / cm 3 ) 1/2 , and more preferably 18 (cal / cm 3 ) 1/2 to 20 (cal / cm 3 ) 1/2 .
  • component transfer between the pressure-sensitive adhesive layer / the sealing resin is preferably prevented.
  • the acrylic pressure-sensitive adhesive for example, an acrylic polymer (homopolymer or copolymer) using one or more (meth) acrylic acid alkyl esters as a monomer component is used as a prepolymer, and the prepolymer is used.
  • acrylic pressure-sensitive adhesives using a crosslinked polymer as a base polymer.
  • the "base polymer" contained in the acrylic pressure-sensitive adhesive in the pressure-sensitive adhesive layer means a polymer formed by cross-linking a prepolymer (uncrosslinked polymer).
  • the base polymer has a crosslinked structure of an acrylic polymer and an epoxy crosslinker.
  • (meth) acrylic acid alkyl ester examples include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, propyl (meth) acrylic acid, isopropyl (meth) acrylic acid, and butyl (meth) acrylic acid.
  • a (meth) acrylic acid alkyl ester having a linear or branched alkyl group having 4 to 20 carbon atoms (more preferably 6 to 20, particularly preferably 8 to 18) is more preferable.
  • a (meth) acrylic acid alkyl ester having a linear or branched alkyl group having 4 or more carbon atoms (preferably 8 or more carbon atoms) is used.
  • the component transfer between the pressure-sensitive adhesive layer / the sealing resin is preferably prevented.
  • the acrylic polymer is another monomer component that can be copolymerized with the (meth) acrylic acid alkyl ester, if necessary, for the purpose of modifying the cohesiveness, heat resistance, crosslinkability and the like. It may contain the unit corresponding to.
  • monomer components include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride and icotanic acid anhydride.
  • Acid anhydride monomers such as (meth) hydroxyethyl acrylate, (meth) hydroxypropyl acrylate, (meth) hydroxybutyl acrylate, (meth) hydroxyhexyl acrylate, (meth) hydroxyoctyl acrylate, (meth) Hydroxyl group-containing monomers such as hydroxydecyl acrylate, hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) methylmethacrylate; styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid.
  • Aminoalkyl (meth) acrylate monomers such as aminoethyl, t-butylaminoethyl (meth) acrylate; alkoxyalkyl (meth) acrylate such as methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate.
  • Maleimide-based monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-phenylmaleimide; N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide , N-2-ethylhexylitaconimide, N-cyclohexylitaconimide, N-laurylitaconimide and other itaconeimide-based monomers; Succinimide-based monomers such as N- (meth) acryloyl-8-oxyoctamethylene succinimide; vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrro Vinyls such as lidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazin, vinylpyrazine, vinylpyrrole, vinylimidazole,
  • Acrylic acid ester-based monomers having such factors: hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol.
  • Polyfunctional monomers such as di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy acrylate, polyester acrylate, urethane acrylate; isoprene, butadiene, Olefin-based monomers such as isobutylene; vinyl ether-based monomers such as vinyl ether and the like can be mentioned. These monomer components may be used alone or in combination of two or more.
  • the acrylic polymer has a glass transition temperature (Tg) of ⁇ 5 ° C. to 150 ° C. (preferably 50 ° C. to 150 ° C., more preferably 80 ° C.) when homopolymerized. It further contains a constituent unit a derived from a monomer ( ⁇ 120 ° C.). If such a structural unit a is included, the molecular motion of the acrylic polymer is restricted, and an acrylic polymer in which the T 2 relaxation time (T 2s ) of the S component by pulse NMR is preferably adjusted can be obtained. In addition, an adhesive sheet having excellent low-temperature adhesiveness can be obtained.
  • Tg glass transition temperature
  • the content of the structural unit a is preferably 0.1% by weight to 20% by weight, more preferably 1% by weight to 10% by weight, particularly, with respect to all the structural units constituting the acrylic polymer. It is preferably 1.5% by weight to 8% by weight, and most preferably 3% by weight to 6% by weight.
  • Examples of the monomer having a glass transition temperature (Tg) of -5 ° C to 150 ° C include 2-hydroxyethyl acrylate (Tg: -3 ° C), 2-hydroxyethyl methacrylate (Tg: 77 ° C), and acrylic acid (Tg).
  • methyl methacrylate is preferable for improving the visibility of the adherend during processing because it enhances the transparency of the pressure-sensitive adhesive layer, and acrylic acid is strongly adhered to the adherend due to the interaction between molecules.
  • Hydroxyethyl acrylate is more preferable for controlling the relaxation time because it exhibits high reactivity with various cross-linking agents.
  • the acrylic polymer (prepolymer) further contains a structural unit derived from a hydroxyl group-containing monomer.
  • the content of the structural unit derived from the hydroxyl group-containing monomer is preferably 0.1% by weight to 20% by weight, more preferably 0.5% by weight to 10% by weight, based on all the structural units constituting the acrylic polymer. It is% by weight, and particularly preferred is 1% by weight to 7% by weight.
  • the acrylic pressure-sensitive adhesive may contain any suitable additive, if necessary.
  • the additive include a cross-linking agent, a tackifier, a plasticizer (for example, a trimellitic acid ester-based plasticizer, a pyromellitic acid ester-based plasticizer, etc.), a pigment, a dye, a filler, an antiaging agent, and a conductive material.
  • a plasticizer for example, a trimellitic acid ester-based plasticizer, a pyromellitic acid ester-based plasticizer, etc.
  • a pigment for example, a trimellitic acid ester-based plasticizer, a pyromellitic acid ester-based plasticizer, etc.
  • a pigment for example, a trimellitic acid ester-based plasticizer, a pyromellitic acid ester-based plasticizer, etc.
  • a dye for example, a trimellitic acid ester-based plasticizer, a pyromellitic acid ester-based plastic
  • cross-linking agent contained in the acrylic pressure-sensitive adhesive examples include an isocyanate-based cross-linking agent, an epoxy-based cross-linking agent, a melamine-based cross-linking agent, a peroxide-based cross-linking agent, a urea-based cross-linking agent, and a metal alkoxide-based cross-linking agent.
  • examples thereof include a metal chelate-based cross-linking agent, a metal salt-based cross-linking agent, a carbodiimide-based cross-linking agent, an oxazoline-based cross-linking agent, an aziridine-based cross-linking agent, and an amine-based cross-linking agent.
  • the amount of the cross-linking agent compounded with respect to the carboxyl group of the acrylic polymer (prepolymer) is preferably 0.08 molar equivalent to 2 molar equivalent, and more preferably 0.1 molar equivalent to 1. It is a molar equivalent. Within such a range, an acrylic pressure-sensitive adhesive having a high crosslink density can be formed, and component transfer between the pressure-sensitive adhesive layer and the sealing resin is preferably prevented.
  • the blending amount of the cross-linking agent here means the content of the cross-linking agent before the acrylic polymer is cross-linked.
  • isocyanate-based cross-linking agent contained in the acrylic pressure-sensitive adhesive include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate.
  • Aromatic isocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate; Trimethylol propane / tolylene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., Commodity) Name "Coronate L”), Trimethylol propane / hexamethylene diisocyanate trimeric adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "Coronate HL”), isocyanurate form of hexamethylene diisocyanate (manufactured by Japan Polyurethane Industry Co., Ltd., product) Isocyanate adducts such as the name "Coronate HX”); and the like.
  • Aromatic isocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane di
  • the blending amount of the isocyanate-based cross-linking agent can be set to an arbitrary appropriate amount according to the desired adhesive strength, and is typically 0.1 part by weight to 20 parts by weight with respect to 100 parts by weight of the acrylic polymer. Parts, more preferably 1 part by weight to 10 parts by weight. Within such a range, a pressure-sensitive adhesive sheet having a small amount of residual carboxyl groups of the components in the pressure-sensitive adhesive layer can be obtained.
  • the blending amount of the cross-linking agent here means the content of the cross-linking agent before the acrylic polymer is cross-linked.
  • an epoxy-based cross-linking agent is preferably used as the cross-linking agent. If an epoxy-based cross-linking agent is used, a pressure-sensitive adhesive sheet capable of preferably reducing the step between the semiconductor chip and the sealing resin can be obtained. In addition, it is possible to form a pressure-sensitive adhesive layer having a high cohesive force, and it is possible to more effectively prevent the displacement of the adherend.
  • Examples of the epoxy-based cross-linking agent contained in the acrylic-based pressure-sensitive adhesive include N, N, N', N'-tetraglycidyl-m-xylene diamine, diglycidyl aniline, and 1,3-bis (N, N-).
  • the blending amount of the epoxy-based cross-linking agent can be set to an arbitrary appropriate amount according to the desired adhesive strength, and is typically 0.01 parts by weight to 50 parts by weight with respect to 100 parts by weight of the acrylic polymer. It is, more preferably 0.6 parts by weight to 15 parts by weight, still more preferably 2 parts by weight to 13 parts by weight, and particularly preferably 3 parts by weight to 10 parts by weight. Is. Within such a range, a pressure-sensitive adhesive sheet having a small amount of residual carboxyl groups of the components in the pressure-sensitive adhesive layer can be obtained.
  • the blending amount of the cross-linking agent here means the content of the cross-linking agent before the acrylic polymer is cross-linked.
  • a cross-linking agent containing N atoms is used as the epoxy-based cross-linking agent.
  • the use of a cross-linking agent containing N atoms is advantageous in that the cross-linking reaction is promoted by catalytic action and the pressure-sensitive adhesive can be easily gelled.
  • any appropriate pressure-sensitive adhesive is used.
  • a tackifier resin is used.
  • the tackifier resin include rosin-based tackifier resins (eg, unmodified rosin, modified rosin, rosinphenol-based resins, rosin ester-based resins, etc.) and terpene-based tackifier resins (eg, terpene-based resins, terpenes).
  • a rosin-based tackifier resin a terpene-based tackifier resin, or a hydrocarbon-based tackifier resin (styrene-based resin, etc.) is preferable.
  • the tackifier may be used alone or in combination of two or more.
  • the amount of the tackifier added is preferably 5 parts by weight to 100 parts by weight, and more preferably 8 parts by weight to 50 parts by weight with respect to 100 parts by weight of the base polymer.
  • a resin having a high softening point or a glass transition temperature (Tg) is used as the tackifier resin.
  • Tg glass transition temperature
  • a resin having a high softening point or glass transition temperature (Tg) By using a resin having a high softening point or glass transition temperature (Tg), a pressure-sensitive adhesive layer capable of exhibiting high adhesiveness is formed even in a high-temperature environment (for example, in a high-temperature environment such as processing at the time of encapsulating a semiconductor chip). can do.
  • the softening point of the tackifier is preferably 100 ° C. to 180 ° C., more preferably 110 ° C. to 180 ° C., and even more preferably 120 ° C. to 180 ° C.
  • the glass dislocation temperature (Tg) of the tackifier is preferably 100 ° C. to 180 ° C., more preferably 110 ° C. to 180 ° C., and even more preferably 120 ° C. to 180
  • a low-polarity tackifier resin is used as the tackifier resin. If a low-polarity tackifier resin is used, a pressure-sensitive adhesive layer having a low affinity with the sealing material can be formed.
  • the low-polarity tackifier resin include an aliphatic hydrocarbon resin, an aliphatic cyclic hydrocarbon resin, an aromatic hydrocarbon resin (for example, a styrene resin, a xylene resin, etc.), and an aliphatic / aromatic resin. Examples thereof include based petroleum resins, aliphatic / alicyclic petroleum resins, and hydrogenated hydrocarbon resins, which are hydrocarbon-based tackifier resins.
  • a tackifier having 5 to 9 carbon atoms is preferable. This is because such a pressure-sensitive adhesive has low polarity, is excellent in compatibility with an acrylic polymer, does not undergo phase separation in a wide temperature range, and can form a pressure-sensitive adhesive layer having excellent stability. ..
  • the acid value of the tackifier resin is preferably 40 or less, more preferably 20 or less, and further preferably 10 or less. Within such a range, a pressure-sensitive adhesive layer having a low affinity with the sealing material can be formed.
  • the hydroxyl value of the tackifier resin is preferably 60 or less, more preferably 40 or less, and further preferably 20 or less. Within such a range, a pressure-sensitive adhesive layer having a low affinity with the sealing material can be formed.
  • Base material examples include resin sheets, non-woven fabrics, papers, metal foils, woven fabrics, rubber sheets, foam sheets, and laminates thereof (particularly, laminates including resin sheets).
  • the resin constituting the resin sheet include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyethylene (PE), polypropylene (PP), ethylene-propylene copolymer, and ethylene-.
  • Vinyl acetate copolymer (EVA), polyamide (nylon), total aromatic polyamide (aramid), polyimide (PI), polyvinyl chloride (PVC), polyphenylene sulfide (PPS), fluororesin, polyether ether ketone (PEEK) ) Etc.
  • EVA Vinyl acetate copolymer
  • nylon polyamide
  • aramid total aromatic polyamide
  • PI polyimide
  • PVC polyvinyl chloride
  • PPS polyphenylene sulfide
  • fluororesin polyether ether ketone
  • Etc. Polyether ether ketone
  • the non-woven fabric include non-woven fabrics made of natural fibers having heat resistance such as non-woven fabrics containing Manila hemp; synthetic resin non-woven fabrics such as polypropylene resin non-woven fabrics, polyethylene resin non-woven fabrics and ester resin non-woven fabrics.
  • the metal foil include copper foil, stainless steel foil, aluminum foil and the like.
  • paper include Japanese paper and kraft paper.
  • a resin sheet composed of a resin having a glass transition temperature (Tg) of 25 ° C. or higher (preferably 40 ° C. or higher, more preferably 50 ° C. or higher) is preferably used as the base material. If such a resin sheet is also scattered, the shape of the base material is maintained even by heating during the sealing step, and the embedding of the semiconductor chip in the resin is prevented.
  • Tg glass transition temperature
  • the resin constituting such a resin sheet include polyethylene terephthalate, polyimide, polyethylene naphthalate and the like.
  • the thickness of the base material can be set to an arbitrary appropriate thickness depending on the desired strength or flexibility, the purpose of use, and the like.
  • the thickness of the substrate is preferably 1000 ⁇ m or less, more preferably 25 ⁇ m to 1000 ⁇ m, further preferably 40 ⁇ m to 500 ⁇ m, particularly preferably 60 ⁇ m to 300 ⁇ m, and most preferably 80 ⁇ m to 250 ⁇ m. In one embodiment, a substrate having a thickness of 25 ⁇ m or more is used. When such a base material is used, the shape of the base material is maintained even by pressurization during the sealing step, and embedding of the semiconductor chip in the pressure-sensitive adhesive layer is prevented.
  • the thickness of the substrate is 20% to 90% (preferably 20% to 89%, more preferably 20% to 88%) with respect to the total thickness of the pressure-sensitive adhesive sheet. Within such a range, the semiconductor chip is prevented from being embedded in the pressure-sensitive adhesive layer.
  • the base material may be surface-treated.
  • the surface treatment include corona treatment, chromic acid treatment, ozone exposure, flame exposure, high-voltage impact exposure, ionizing radiation treatment, coating treatment with an undercoat agent, and the like.
  • the organic coating material examples include the materials described in Plastic Hard Coat Material II (CMC Publishing, (2004)).
  • Urethane-based polymers are preferably used, and polyacrylic urethane, polyester urethane or precursors thereof are more preferably used. This is because it is easy to apply and apply to the base material, and various types can be industrially selected and obtained at low cost.
  • the urethane-based polymer is, for example, a polymer composed of a reaction mixture of an isocyanato monomer and an alcoholic hydroxyl group-containing monomer (for example, a hydroxyl group-containing acrylic compound or a hydroxyl group-containing ester compound).
  • the organic coating material may contain a chain extender such as polyamine, an antiaging agent, an oxidation stabilizer and the like as arbitrary additives.
  • the thickness of the organic coating layer is not particularly limited, but is preferably about 0.1 ⁇ m to 10 ⁇ m, preferably about 0.1 ⁇ m to 5 ⁇ m, and more preferably about 0.5 ⁇ m to 5 ⁇ m.
  • the second adhesive layer can be an adhesive layer composed of any suitable adhesive.
  • the second pressure-sensitive adhesive layer further comprises thermally expandable microspheres.
  • the pressure-sensitive adhesive contained in the second pressure-sensitive adhesive layer may be a curable pressure-sensitive adhesive (for example, an active energy ray-curable pressure-sensitive adhesive) or a pressure-sensitive pressure-sensitive adhesive.
  • a curable pressure-sensitive adhesive for example, an active energy ray-curable pressure-sensitive adhesive
  • a pressure-sensitive pressure-sensitive adhesive examples include an acrylic pressure-sensitive adhesive and a rubber-based pressure-sensitive adhesive.
  • JP-A-2018-909050 can be referred to. The entire description of the publication is incorporated herein by reference.
  • any suitable heat-expandable microsphere can be used as long as it is a microsphere that can be expanded or foamed by heating.
  • a microsphere in which a substance that easily expands by heating is contained in an elastic shell can be used.
  • Such a heat-expandable microsphere can be produced by any suitable method, for example, a core selvation method, an interfacial polymerization method, or the like.
  • Substances that easily expand by heating include, for example, propane, propylene, butene, normal butane, isobutane, isopentan, neopentane, normalpentane, normal hexane, isohexane, heptane, octane, petroleum ether, methane halides, and tetraalkylsilanes.
  • Low boiling point liquids such as; azodicarboxylic amides gasified by thermal decomposition; and the like.
  • nitrile monomers such as acrylonitrile, methacrylonitrile, ⁇ -chloroacrylonitrile, ⁇ -ethoxyacrylonitrile, and fumaronitrile; acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid.
  • Carboxylic acid monomers such as citraconic acid; vinylidene chloride; vinyl acetate; methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, (Meta) acrylic acid esters such as isobornyl (meth) acrylates, cyclohexyl (meth) acrylates, benzyl (meth) acrylates and ⁇ -carboxyethyl acrylates; styrene monomers such as styrene, ⁇ -methylstyrene and chlorostyrene; acrylamides and substituted acrylamides.
  • Acrylic acid esters such as isobornyl (meth) acrylates, cyclohexyl (meth) acrylates, benzyl (meth) acrylates and ⁇ -carboxye
  • Acrylate monomers such as methacrylicamide and substituted methacrylicamide; and the like.
  • the polymer composed of these monomers may be a homopolymer or a copolymer.
  • the copolymer include vinylidene chloride-methyl methacrylate-acrylonitrile copolymer, methyl methacrylate-acrylonitrile-methacrylonitrile copolymer, methyl methacrylate-acrylonitrile copolymer, and acrylonitrile-methacrylonitrile-itaconic acid. Examples include polymers.
  • an inorganic foaming agent or an organic foaming agent may be used as the heat-expandable microspheres.
  • the inorganic foaming agent include ammonium carbonate, ammonium hydrogencarbonate, sodium hydrogencarbonate, ammonium nitrite, sodium boron hydroxide, various azides and the like.
  • the organic foaming agent include salt fluoride alkane-based compounds such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarboxylicamide, and barium azodicarboxylate.
  • Hydrazide compounds such as paratoluenesulfonyl hydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxybis (benzenesulfonylhydrazide), allylbis (sulfonylhydrazide); p-toluylenesulfonyl semicarbazide, 4, Semicarbazide compounds such as 4'-oxybis (benzenesulfonyl semicarbazide); triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; N, N'-dinitrosopentamethylenetetramine, N, N' Examples thereof include N-nitroso compounds such as -dimethyl-N, N'-dinitrosoterephthalamide; and the like.
  • the particle size of the heat-expandable microspheres before heating is preferably 0.5 ⁇ m to 80 ⁇ m, more preferably 5 ⁇ m to 45 ⁇ m, still more preferably 10 ⁇ m to 20 ⁇ m, and particularly preferably 10 ⁇ m to 15 ⁇ m. .. Therefore, the particle size of the heat-expandable microspheres before heating is preferably 6 ⁇ m to 45 ⁇ m, more preferably 15 ⁇ m to 35 ⁇ m in terms of average particle size.
  • the above particle size and average particle size are values obtained by the particle size distribution measurement method in the laser scattering method.
  • the heat-expandable microspheres preferably have an appropriate strength that does not burst until the coefficient of thermal expansion is preferably 5 times or more, more preferably 7 times or more, and even more preferably 10 times or more.
  • the adhesive strength can be efficiently reduced by the heat treatment.
  • the content ratio of the heat-expandable microspheres in the pressure-sensitive adhesive layer can be appropriately set according to the desired decrease in adhesive strength and the like.
  • the content of the heat-expandable microspheres is, for example, 1 part by weight to 150 parts by weight, preferably 10 parts by weight to 130 parts by weight, based on 100 parts by weight of the base polymer forming the second pressure-sensitive adhesive layer. More preferably, it is 25 parts by weight to 100 parts by weight.
  • the arithmetic surface roughness Ra of the pressure-sensitive adhesive layer before the heat-expandable microspheres expand is preferably 500 nm or less, more preferably. Is 400 nm or less, more preferably 300 nm or less. Within such a range, an adhesive sheet having excellent adhesion to the adherend can be obtained.
  • the pressure-sensitive adhesive layer having excellent surface smoothness can be obtained by, for example, setting the thickness of the pressure-sensitive adhesive layer within the above range, or by applying the pressure-sensitive adhesive layer to a peeling liner and transferring the pressure-sensitive adhesive layer when another pressure-sensitive adhesive layer is provided. ,Obtainable.
  • the other pressure-sensitive adhesive layer may contain heat-expandable microspheres. Even when another pressure-sensitive adhesive layer contains heat-expandable microspheres, the arithmetic surface roughness Ra of the pressure-sensitive adhesive layer is preferably in the above range.
  • the pressure-sensitive adhesive layer contains thermally expandable microspheres
  • the pressure-sensitive adhesive layer is composed of a base polymer having a dynamic storage elastic modulus in the range of 5 kPa to 1 MPa (more preferably 10 kPa to 0.8 MPa) at 80 ° C. It is preferable to include a pressure-sensitive adhesive. With such a pressure-sensitive adhesive layer, it is possible to form a pressure-sensitive adhesive sheet which has an appropriate adhesiveness before heating and whose adhesive strength tends to decrease by heating.
  • the dynamic storage elastic modulus can be measured by using a dynamic viscoelasticity measuring device (for example, trade name "ARES” manufactured by Leometrics Co., Ltd.) under measurement conditions of a frequency of 1 Hz and a heating rate of 10 ° C./min. ..
  • a dynamic viscoelasticity measuring device for example, trade name "ARES” manufactured by Leometrics Co., Ltd.
  • the adhesive sheet of the present invention can be produced by any suitable method.
  • the pressure-sensitive adhesive sheet of the present invention is formed, for example, by directly applying a composition containing an acrylic pressure-sensitive adhesive onto a substrate, or by applying a composition containing an acrylic-based pressure-sensitive adhesive onto any suitable substrate. Examples thereof include a method of transferring the applied coating layer to a base material.
  • the composition containing the acrylic pressure-sensitive adhesive may contain any suitable solvent.
  • a composition containing the heat-expandable microspheres, a pressure-sensitive adhesive, and an arbitrary suitable solvent is applied to a substrate to form the pressure-sensitive adhesive layer.
  • the heat-expandable microspheres are embedded in the pressure-sensitive adhesive using a laminator or the like to form a pressure-sensitive adhesive layer containing the heat-expandable microspheres. It may be formed.
  • each layer can be formed by drying after application.
  • the coating method include a coating method using a multi-coater, a die coater, a gravure coater, an applicator, and the like.
  • the drying method include natural drying and heat drying. The heating temperature for heat-drying can be set to any suitable temperature depending on the characteristics of the substance to be dried.
  • T 2 relaxation time (T 2s ) of S component by pulse NMR of the pressure-sensitive adhesive layer Using the trade name "TD-NMR the minispec mq20" manufactured by Bruker, a T 2 relaxation curve measured by the solid echo method was obtained using a pressure-sensitive adhesive layer of 100 mg as a measurement sample, and the T 2 relaxation curve was obtained by the following formula (1). ), And the T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer. Asked.
  • M (t) ⁇ ⁇ exp (-(1 / Wa) (t / T 2s ) Wa ) + ⁇ ⁇ exp (-(1 / Wa) (t / T 2L ) Wa ) ⁇ ⁇ ⁇ (1)
  • ⁇ Proton ratio (%) of component (S component) with short relaxation time
  • T 2s T 2 relaxation time (msec) of S component
  • ⁇ Proton ratio (%) of the component (L component) with a long relaxation time
  • T 2L T 2 relaxation time (msec) of L component
  • t Observation time (msec)
  • Adhesive strength (against PET) 2 kg of SUS304 plate via double-sided adhesive tape (manufactured by Nitto Denko, trade name "No. 531") on the entire surface of the adhesive sheet (width 20 mm x length 140 mm) opposite to the adhesive layer. It was attached using a hand roller.
  • a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumirror S-10", thickness: 25 ⁇ m, width: 30 mm) was attached to the entire surface of the pressure-sensitive adhesive layer (temperature: 23 ° C., humidity: 65%). 2kg roller 1 round trip).
  • the evaluation sample obtained as described above was subjected to a tensile test.
  • the trade name "Shimadzu Autograph AG-120kN” manufactured by Shimadzu Corporation was used as the tensile tester. After setting the evaluation sample in the tensile tester, the sample was left at an environmental temperature of 23 ° C. for 30 minutes, and then the tensile test was started. The conditions for the tensile test were a peeling angle of 180 ° and a peeling speed (pulling speed): 300 mm / min. The load when the adhesive sheet was peeled off from the PET film was measured, and the maximum load at that time was taken as the adhesive force of the adhesive sheet.
  • Adhesive strength (anti-sealing resin)
  • a mold (mold size: 35 mm x 90 mm rectangle, thickness: 564 ⁇ m) is bonded onto the first pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet (width 50 mm ⁇ length 140 mm), and a granular epoxy resin system is used in the mold.
  • the sealing material G730 manufactured by Sumitomo Bakelite Co., Ltd.
  • cover it with a silicone-treated release liner cover it with a silicone-treated release liner, and apply the "hydraulic molding machine NS-VPF" manufactured by Meijo Press Co., Ltd.
  • the sealing resin was cured in an oven under a heating environment of 150 ° C. ⁇ 7 hours. After the curing of the sealing resin was completed, the sample was allowed to stand at 23 ° C. and 50% RH for 2 hours, and then the portion where the sealing resin and the first adhesive layer were in contact was cut into a width of 20 mm and a length of 88 mm. ..
  • the evaluation sample obtained as described above was subjected to a tensile test.
  • the trade name "Shimadzu Autograph AG-120kN” manufactured by Shimadzu Corporation was used as the tensile tester. After setting the evaluation sample in the tensile tester, the sample was left at an environmental temperature of 23 ° C. for 30 minutes, and then the tensile test was started. The conditions for the tensile test were a peeling angle of 180 ° and a peeling speed (pulling speed): 300 mm / min. The load when the adhesive sheet was peeled off from the sealing resin was measured, and the average load at that time was taken as the adhesive force of the adhesive sheet.
  • Step between the semiconductor chip and the sealing resin The sealing step is carried out on the surface of the adhesive of the adhesive tape under the conditions described below, and the height of the step at the interface between the semiconductor chip (Si chip) and the sealing resin (6) Stand-off) was measured.
  • Carrier SUS carrier 220mm ⁇ Chip: Si mirror chip 7 mm x 7 mm x 400 ⁇ m thickness Bonding device: FC3000W (manufactured by Toray Industries, Ltd.) Bonding conditions: Crimping time: 6 seconds Crimping pressure: 10N Crimping temperature: 23 ° C Sealing equipment: MS-150HP (manufactured by Apic Yamada) Encapsulating resin: G730 (manufactured by Sumitomo Bakelite) Preheat conditions: 130 ° C x 30 seconds Time from preheat to the start of sealing: 1 hour Sealing temperature: 145 ° C Vacuum time: 5 seconds Sealing time: 600 seconds Clamping force: 3.6 MPa Sealing thickness: 600 ⁇ m The sealing work was carried out according to the following procedure.
  • the laminate was heated on a hot plate, and the adhesive attached to the SUS carrier was foamed and peeled off to form SUS.
  • the carrier was separated.
  • the adhesive tape was peeled off from the laminated body after separating the SUS carrier to obtain a sealing resin and a sealing body of Si chips.
  • the step at the interface between the Si chip and the sealing resin on the surface that was in contact with the adhesive of the sealing resin and the sealing body of the Si chip was measured using a laser confocal microscope (OLS-4000 OLYMPUS). The height of the step at the interface between the sealing resin and the Si chip was measured.
  • epoxy-based cross-linking agent Mitsubishi Gas Chemicals, Inc.
  • the composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 ⁇ m) as a base material, and the base material and the first pressure-sensitive adhesive layer (manufactured by Toray Industries, Inc., thickness 38 ⁇ m) are coated.
  • Acrylic copolymer C (2-ethylhexyl acrylate, ethyl acrylate, methyl methacrylate and 2-hydroxyethyl acrylate) on the surface of the pressure-sensitive adhesive sheet (1) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film.
  • the composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 ⁇ m) as a base material, and the base material and the first pressure-sensitive adhesive layer (manufactured by Toray Industries, Inc., thickness 38 ⁇ m) are coated.
  • An adhesive sheet (2) composed of a thickness of 10 ⁇ m) was obtained.
  • a second pressure-sensitive adhesive layer was formed on the surface of the pressure-sensitive adhesive sheet (2) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film in the same manner as in Example 1 to obtain a double-sided pressure-sensitive adhesive sheet.
  • epoxy-based cross-linking agent manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name "Tetrad C
  • tackifier manufactured by Yasuhara Chemical Co., Ltd., trade name
  • the composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 ⁇ m) as a base material, and the base material and the first pressure-sensitive adhesive layer (manufactured by Toray Industries, Inc., thickness 38 ⁇ m) are coated.
  • An adhesive sheet (3) composed of a thickness of 10 ⁇ m) was obtained.
  • a second pressure-sensitive adhesive layer was formed on the surface of the pressure-sensitive adhesive sheet (3) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film in the same manner as in Example 1 to obtain a double-sided pressure-sensitive adhesive sheet.
  • Example 4 A double-sided pressure-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name “Lumilar S10”, thickness 100 ⁇ m) was used as a base material.
  • a polyethylene terephthalate film manufactured by Toray Industries, Inc., trade name “Lumilar S10”, thickness 100 ⁇ m
  • the composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 ⁇ m) as a base material, and the base material and the pressure-sensitive adhesive layer (thickness 10 ⁇ m) are coated.
  • An adhesive sheet (4) composed of the above was obtained.
  • a second pressure-sensitive adhesive layer was formed on the surface of the pressure-sensitive adhesive sheet (4) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film in the same manner as in Example 1 to obtain a double-sided pressure-sensitive adhesive sheet.
  • a composition for forming a pressure-sensitive adhesive layer was prepared by mixing 1.5 parts by weight of an agent (manufactured by Toso Co., Ltd., trade name "Coronate L”) and 100 parts by weight of toluene.
  • the composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 ⁇ m) as a base material, and the base material and the pressure-sensitive adhesive layer (thickness 10 ⁇ m) are coated.
  • An adhesive sheet (5) composed of the above was obtained.
  • a second pressure-sensitive adhesive layer was formed on the surface of the pressure-sensitive adhesive sheet (5) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film in the same manner as in Example 1 to obtain a double-sided pressure-sensitive adhesive sheet.
  • Base material Adhesive layer 30 Second adhesive layer 100, 200 Adhesive sheet

Landscapes

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

Abstract

Provided is an adhesive sheet which has an appropriate adhesiveness to a sealing resin that seals a semiconductor chip and to the semiconductor chip, and can be easily peeled off from the sealing resin, and in which it is difficult for adhesive residue to occur during peeling, and after peeling off the adhesive sheet, it is difficult to create a height difference between the semiconductor chip and the sealing resin.　The adhesive sheet of the present invention comprises: a base material; and an adhesive layer disposed on at least one side of the base material, wherein the adhesive layer contains an acrylic adhesive, the amount of subduction of the adhesive sheet in an environment of 23°C using TMA is 5 μm or less, and the T2 relaxation time (T2s) of an S component of the adhesive layer by pulse NMR is 45 μsec or less.

Description

粘着シートAdhesive sheet
　本発明は、粘着シートに関する。 The present invention relates to an adhesive sheet.
　近年、半導体チップを含む半導体部品の製造において、半導体チップの傷つき防止、金属配線の拡張等のために、当該半導体チップを樹脂封止することが行われることがある。樹脂封止工程では、作業性等の観点から、粘着シート上で、半導体チップを樹脂封止することが行われることがある。例えば、半導体チップの移動を防止するために、複数の半導体チップを所定の仮固定材としての粘着シート上に配置し、当該粘着シート上で、半導体チップを一括に封止する。その後、所定の後工程においては、半導体チップを封止した樹脂から、上記粘着シートを剥離する。 In recent years, in the manufacture of semiconductor parts including semiconductor chips, the semiconductor chips may be resin-sealed in order to prevent damage to the semiconductor chips, expand metal wiring, and the like. In the resin sealing step, the semiconductor chip may be resin-sealed on the pressure-sensitive adhesive sheet from the viewpoint of workability and the like. For example, in order to prevent the semiconductor chips from moving, a plurality of semiconductor chips are arranged on an adhesive sheet as a predetermined temporary fixing material, and the semiconductor chips are collectively sealed on the adhesive sheet. Then, in a predetermined post-process, the pressure-sensitive adhesive sheet is peeled off from the resin encapsulating the semiconductor chip.
　上記のような工程において、従来の粘着シートを用いると、封止樹脂と半導体チップとを含む構造体から当該粘着シートを剥離する際に、該構造体に糊残りが生じるという問題がある。また、封止する際に、半導体チップが粘着シートに押し込まれた結果、粘着シートを剥離した後に、半導体チップと封止樹脂との段差が生じるという問題がある。このような段差は、半導体チップの保護が不十分となったり、金属配線が形成できなくなるといった不具合の原因となる。また、当該段差起因の糊残りも生じやすくなる。 When a conventional pressure-sensitive adhesive sheet is used in the above-mentioned process, there is a problem that adhesive residue is generated on the structure when the pressure-sensitive adhesive sheet is peeled off from the structure containing the sealing resin and the semiconductor chip. Further, as a result of the semiconductor chip being pushed into the pressure-sensitive adhesive sheet during sealing, there is a problem that a step is generated between the semiconductor chip and the sealing resin after the pressure-sensitive adhesive sheet is peeled off. Such a step causes problems such as insufficient protection of the semiconductor chip and the inability to form metal wiring. In addition, adhesive residue due to the step is likely to occur.
特開２００１－３０８１１６号公報Japanese Unexamined Patent Publication No. 2001-308116 特開２００１－３１３３５０号公報Japanese Unexamined Patent Publication No. 2001-313350
　本発明は上記従来の課題を解決するためになされたものであり、その目的とするところは、半導体チップを封止する封止樹脂および半導体チップに対して適度な粘着性を有し、該封止樹脂から容易に剥離することができ、剥離時の糊残りが生じ難く、かつ、粘着シートを剥離した後に、半導体チップと封止樹脂との段差を生じさせにくい、粘着シートを提供することにある。 The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to have an appropriate adhesiveness to a sealing resin for encapsulating a semiconductor chip and a semiconductor chip, and the sealing thereof. To provide an adhesive sheet that can be easily peeled off from the stop resin, does not easily leave adhesive residue during peeling, and does not easily cause a step between the semiconductor chip and the sealing resin after the adhesive sheet is peeled off. be.
　本発明の粘着シートは、基材と、該基材の少なくとも片側に配置された粘着剤層とを備える粘着シートであって、該粘着剤層が、アクリル系粘着剤を含み、該粘着シートのＴＭＡを用いた２３℃環境下における沈み込み量が、５μｍ以下であり、該粘着剤層のパルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）が４５μｓｅｃ以下である。
　１つの実施形態においては、上記粘着剤層表面に、４－ターシャリーブチルフェニルグリシジルエーテルを滴下し、１分間静置した後の該粘着剤層の厚み変化率が、１６０％以下である。
　１つの実施形態においては、上記粘着剤層表面に、４－ターシャリーブチルフェニルグリシジルエーテルを滴下し、１分間静置した後の該粘着剤層の厚み変化量が、２０μｍ以下である。
　１つの実施形態においては、上記粘着剤層が粘着剤を含み、該粘着剤が、ｓｐ値が１８（ｃａｌ／ｃｍ３）１／２～２０（ｃａｌ／ｃｍ３）１／２であるベースポリマーを含む。
　１つの実施形態においては、上記アクリル系粘着剤が、ベースポリマーとして、アクリル系ポリマーの架橋体を含む。
　１つの実施形態においては、上記アクリル系粘着剤が、エポキシ系架橋剤を含む。
　１つの実施形態においては、上記エポキシ系架橋剤の配合量が、アクリル系ポリマー１００重量部に対して、０．６重量部～１５重量部である。
　１つの実施形態においては、上記基材が、ガラス転移温度（Ｔｇ）が２５℃以上の樹脂から構成される樹脂シートである。
　１つの実施形態においては、上記基材の厚みが、粘着シートの総厚に対して、２０％～９０％、である。
　１つの実施形態においては、上記粘着シートのＴＭＡを用いた１４５℃環境下における沈み込み量が、１μｍ～３５μｍである。
　１つの実施形態においては、上記粘着剤層を加熱処理した際の窒素ガスの発生量が、０．０６重量％～１重量％である。
　１つの実施形態においては、上記粘着シートは、上記基材と、該基材の片側に配置された上記粘着剤層と、該基材の該粘着剤層とは反対側に配置された第２の粘着剤層とを備える。
　１つの実施形態においては、上記粘着シートは、半導体チップの樹脂封止工程で用いられる仮固定材である。
　１つの実施形態においては、上記粘着シートは、上記粘着シート上で、封止樹脂を硬化する際に用いられる。 The pressure-sensitive adhesive sheet of the present invention is a pressure-sensitive adhesive sheet including a base material and a pressure-sensitive adhesive layer arranged on at least one side of the base material, wherein the pressure-sensitive adhesive layer contains an acrylic pressure-sensitive adhesive, and the pressure-sensitive adhesive sheet is used. The amount of subduction under the environment of 23 ° C. using TMA is 5 μm or less, and the T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is 45 μsec or less.
In one embodiment, the rate of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is 160% or less.
In one embodiment, the amount of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is 20 μm or less.
In one embodiment, the pressure-sensitive adhesive layer comprises a pressure-sensitive adhesive, wherein the pressure-sensitive adhesive has a sp value of 18 (cal / cm 3 ) 1/2 to 20 (cal / cm 3 ) 1/2 . including.
In one embodiment, the acrylic pressure-sensitive adhesive comprises a crosslinked body of the acrylic polymer as a base polymer.
In one embodiment, the acrylic pressure-sensitive adhesive comprises an epoxy-based cross-linking agent.
In one embodiment, the blending amount of the epoxy-based cross-linking agent is 0.6 parts by weight to 15 parts by weight with respect to 100 parts by weight of the acrylic polymer.
In one embodiment, the substrate is a resin sheet composed of a resin having a glass transition temperature (Tg) of 25 ° C. or higher.
In one embodiment, the thickness of the substrate is 20% to 90% with respect to the total thickness of the pressure-sensitive adhesive sheet.
In one embodiment, the amount of subduction of the pressure-sensitive adhesive sheet in an environment of 145 ° C. using TMA is 1 μm to 35 μm.
In one embodiment, the amount of nitrogen gas generated when the pressure-sensitive adhesive layer is heat-treated is 0.06% by weight to 1% by weight.
In one embodiment, the pressure-sensitive adhesive sheet is a second base material, a pressure-sensitive adhesive layer arranged on one side of the base material, and a second surface of the base material opposite to the pressure-sensitive adhesive layer. Provided with a pressure-sensitive adhesive layer.
In one embodiment, the pressure-sensitive adhesive sheet is a temporary fixing material used in the resin sealing step of a semiconductor chip.
In one embodiment, the pressure-sensitive adhesive sheet is used to cure the sealing resin on the pressure-sensitive adhesive sheet.
　本発明によれば、半導体チップを封止する封止樹脂および半導体チップに対して適度な粘着性を有し、該封止樹脂から容易に剥離することができ、剥離時の糊残りが生じ難く、かつ、粘着シートを剥離した後に、半導体チップと封止樹脂との段差を生じさせにくい、粘着シートを提供することができる。 According to the present invention, it has an appropriate adhesiveness to the encapsulating resin for encapsulating a semiconductor chip and the semiconductor chip, can be easily peeled from the encapsulating resin, and is unlikely to leave adhesive residue during peeling. Moreover, it is possible to provide an adhesive sheet that does not easily cause a step between the semiconductor chip and the sealing resin after the adhesive sheet is peeled off.
本発明の１つの実施形態による粘着シートの概略断面図である。It is a schematic sectional drawing of the pressure-sensitive adhesive sheet by one Embodiment of this invention. （ａ）は、従来の粘着シートを半導体チップ樹脂封止工程に使用する場合の一例を説明する図である。（ｂ）は、本発明の粘着シートを半導体チップ樹脂封止工程に使用する場合の一例を説明する図である。(A) is a figure explaining an example of the case where the conventional pressure-sensitive adhesive sheet is used in the semiconductor chip resin encapsulation step. (B) is a figure explaining an example of the case where the pressure-sensitive adhesive sheet of the present invention is used in the semiconductor chip resin encapsulation step. 本発明の別の実施形態による粘着シートの概略断面図である。FIG. 3 is a schematic cross-sectional view of an adhesive sheet according to another embodiment of the present invention.
Ａ．粘着シートの概要
　図１は、本発明の１つの実施形態による粘着シートの概略断面図である。粘着シート１００は、基材１０と、基材１０の少なくとも片側に配置された粘着剤層（第１の粘着剤層）２０とを備える。粘着剤層は、アクリル系粘着剤を含む。 A. Schematic FIG. 1 of the pressure-sensitive adhesive sheet is a schematic cross-sectional view of the pressure-sensitive adhesive sheet according to one embodiment of the present invention. The pressure-sensitive adhesive sheet 100 includes a base material 10 and a pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer) 20 arranged on at least one side of the base material 10. The pressure-sensitive adhesive layer contains an acrylic pressure-sensitive adhesive.
　本発明の粘着シートは、半導体チップを樹脂封止する際の仮固定材として、好適に用いられ得る。より詳細には、本発明の粘着シートは、当該粘着シートの粘着剤層上に半導体チップを配列し、当該半導体チップを樹脂（通常、エポキシ系樹脂）で覆い、当該封止樹脂を硬化することによって半導体チップを樹脂封止する際の、当該半導体チップの仮固定材として用いられ得る。半導体チップを樹脂封止した後、所定の後工程（例えば、封止樹脂の裏面研削、パターン形成、バンプ形成、チップ化（切断））の際には、上記粘着シートは、封止樹脂と半導体チップとから構成される構造体から剥離され得る。封止樹脂のエポキシ当量は、例えば、５０ｇ／ｅｑ～５００ｇ／ｅｑである。 The pressure-sensitive adhesive sheet of the present invention can be suitably used as a temporary fixing material when sealing a semiconductor chip with a resin. More specifically, in the pressure-sensitive adhesive sheet of the present invention, semiconductor chips are arranged on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, the semiconductor chips are covered with a resin (usually an epoxy resin), and the sealing resin is cured. Can be used as a temporary fixing material for the semiconductor chip when the semiconductor chip is resin-sealed. After the semiconductor chip is resin-sealed, the pressure-sensitive adhesive sheet is a sealing resin and a semiconductor during a predetermined post-process (for example, backside grinding of the sealing resin, pattern formation, bump formation, chip formation (cutting)). It can be peeled off from the structure composed of the chip. The epoxy equivalent of the sealing resin is, for example, 50 g / eq to 500 g / eq.
　上記粘着シートのＴＭＡを用いた２３℃環境下における沈み込み量は、５μｍ以下である。また、粘着剤層のパルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）が４５μｓｅｃ以下である。これらの特徴を有する粘着シートによれば、半導体チップを粘着シート上で樹脂封止した後、粘着シートを剥離した際に、半導体チップと封止樹脂との段差の発生が防止される。 The amount of subduction of the pressure-sensitive adhesive sheet in an environment of 23 ° C. using TMA is 5 μm or less. Further, the T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is 45 μsec or less. According to the pressure-sensitive adhesive sheet having these characteristics, when the semiconductor chip is resin-sealed on the pressure-sensitive adhesive sheet and then the pressure-sensitive adhesive sheet is peeled off, the generation of a step between the semiconductor chip and the sealing resin is prevented.
　上記半導体チップと封止樹脂との段差が生じる要因としては、粘着剤層成分の封止樹脂への移行；樹脂封止時に半導体チップに負荷される力による半導体チップの粘着剤層への埋まり込み；等が考えられる。図２（ａ）を用いて、より詳細に説明する。図２（ａ）は、従来の粘着シート１００’を半導体チップの樹脂封止に使用する場合の一例を示す。粘着シート１００’は粘着剤層を有し、該粘着剤層外面を貼着面とする。従来、半導体チップを樹脂封止する際には、まず、粘着シート１００’上に、半導体チップ１を貼着する（ａ－ｉ）。その後、半導体チップ１を封止するようにして、封止樹脂２の前駆体となるモノマーを含む組成物２’を塗布し（ａ－ｉｉ）、その後、該組成物２’を硬化させる（ａ－ｉｉｉ）。なお、上記組成物としては、例えば、ナフタレン型２官能エポキシ樹脂（エポキシ当量：１４４）を含む組成物が用いられる。次いで、所定の後工程の際に、半導体チップ１と封止樹脂２とを含む構造体Ａから、粘着シート１００’を剥離する（ａ－ｉｖ）。このような操作において、（ａ－ｉｉ）に示す工程、および（ａ－ｉｉｉ）に示す工程、粘着剤層と封止樹脂間での成分移行が生じ、封止樹脂中に、粘着剤成分と封止樹脂成分との混合相が形成される。当該混合相が形成されれば、粘着シートを剥離する際に、混合相が破壊されて、封止樹脂の一部が粘着シートとともに剥離され、その結果、半導体チップと封止樹脂との段差が生じる。また、（ａ－ｉｉ）に示す工程および（ａ－ｉｉｉ）に示す工程において、半導体チップに負荷される力により、半導体チップの一部が粘着剤層に埋まり込む。半導体チップの粘着剤層の埋まり込みもまた、半導体チップと封止樹脂との段差の要因となる。 The cause of the step between the semiconductor chip and the sealing resin is the transfer of the pressure-sensitive adhesive layer component to the sealing resin; the embedding of the semiconductor chip in the pressure-sensitive adhesive layer due to the force loaded on the semiconductor chip during resin sealing. ; Etc. are conceivable. This will be described in more detail with reference to FIG. 2 (a). FIG. 2A shows an example of the case where the conventional pressure-sensitive adhesive sheet 100'is used for resin encapsulation of a semiconductor chip. The pressure-sensitive adhesive sheet 100'has a pressure-sensitive adhesive layer, and the outer surface of the pressure-sensitive adhesive layer is used as a sticking surface. Conventionally, when the semiconductor chip is resin-sealed, the semiconductor chip 1 is first attached to the pressure-sensitive adhesive sheet 100'(ai). Then, the composition 2'containing the monomer which is the precursor of the sealing resin 2 is applied (a-ii) so as to seal the semiconductor chip 1, and then the composition 2'is cured (a). -Iii). As the composition, for example, a composition containing a naphthalene-type bifunctional epoxy resin (epoxy equivalent: 144) is used. Next, the pressure-sensitive adhesive sheet 100'is peeled off from the structure A containing the semiconductor chip 1 and the sealing resin 2 during a predetermined post-process (a-iv). In such an operation, the step shown in (a-iii) and the step shown in (a-iii), the component transfer between the pressure-sensitive adhesive layer and the sealing resin occurs, and the pressure-sensitive adhesive component is contained in the sealing resin. A mixed phase with the sealing resin component is formed. If the mixed phase is formed, when the pressure-sensitive adhesive sheet is peeled off, the mixed phase is destroyed and a part of the sealing resin is peeled off together with the pressure-sensitive adhesive sheet, resulting in a step between the semiconductor chip and the sealing resin. Occurs. Further, in the steps shown in (a-iii) and (a-iii), a part of the semiconductor chip is embedded in the pressure-sensitive adhesive layer due to the force applied to the semiconductor chip. The embedding of the pressure-sensitive adhesive layer of the semiconductor chip also causes a step difference between the semiconductor chip and the sealing resin.
　本発明においては、ＴＭＡを用いた２３℃環境下における沈み込み量を５μｍ以下とすることにより、粘着剤層成分の封止樹脂への移行および半導体チップの粘着剤層への埋まり込み（特に、半導体チップの粘着剤層への埋まり込み）を防止することができる（図２（ｂ））。また、粘着剤層のパルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）を４５μｓｅｃ以下とすることにより、粘着剤層成分の封止樹脂への移行および半導体チップの粘着剤層への埋まり込み（特に、粘着剤層成分の封止樹脂への移行）を防止することができる（図２（ｂ））。 In the present invention, by setting the sinking amount in a 23 ° C. environment using TMA to 5 μm or less, the pressure-sensitive adhesive layer component is transferred to the sealing resin and the semiconductor chip is embedded in the pressure-sensitive adhesive layer (particularly). (Embedding of the semiconductor chip into the pressure-sensitive adhesive layer) can be prevented (FIG. 2 (b)). Further, by setting the T 2 relaxation time (T 2s ) of the S component of the pressure-sensitive adhesive layer by pulse NMR to 45 μsec or less, the pressure-sensitive adhesive layer component is transferred to the sealing resin and the semiconductor chip is embedded in the pressure-sensitive adhesive layer. (In particular, the transfer of the pressure-sensitive adhesive layer component to the sealing resin) can be prevented (FIG. 2 (b)).
　粘着シートのＴＭＡを用いた２３℃環境下における沈み込み量は、好ましくは４μｍ以下であり、より好ましくは３．５μｍであり、さらに好ましくは３μｍ以下である。このような範囲であれば、本発明の効果は顕著となる。粘着シートのＴＭＡを用いた２３℃環境下における沈み込み量は、小さいほど好ましいが、その下限は好ましくは０．１μｍ（好ましくは０．０１μｍ）である。例えば、粘着剤層を構成する粘着剤の組成、当該粘着剤に含まれるベースポリマーの構造（特に、架橋密度）を適切に調整することにより、上記範囲の沈み込み量とすることができる。 The amount of subduction of the pressure-sensitive adhesive sheet in an environment of 23 ° C. using TMA is preferably 4 μm or less, more preferably 3.5 μm, and further preferably 3 μm or less. Within such a range, the effect of the present invention becomes remarkable. The smaller the amount of the pressure-sensitive adhesive sheet subducted in the environment of 23 ° C. using TMA, the more preferable, but the lower limit thereof is preferably 0.1 μm (preferably 0.01 μm). For example, by appropriately adjusting the composition of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer and the structure (particularly, the cross-linking density) of the base polymer contained in the pressure-sensitive adhesive, the sinking amount can be set within the above range.
　「粘着シートのＴＭＡを用いた２３℃環境下における沈み込み量」は、熱機械分析機を用いて、粘着剤層（第１の粘着剤層）にプローブを接触させて６０分経過させた後の沈み込み量を意味する。測定条件は、プローブ：針入、窒素ガス流量：５０．０ｍｌ／ｍｉｎ、押し込み荷重：０．０１Ｎとされる。また、粘着シートが基材の片側にのみ粘着剤層を有する場合（すなわち、後述の第２の粘着剤層を有さない場合）、基材の粘着剤層（第１の粘着剤層）とは反対側の面に、標準粘着剤層を形成させた後に、上記の測定が行われる。標準粘着剤層は、アクリル系コポリマー（２－エチルヘキシルアクリレート（２ＥＨＡ）、エチルアクリレート（ＥＡ）、メチルメタクリレート（ＭＭＡ）および２－ヒドロキシエチルアクリレート（ＨＥＡ）のコポリマー、２ＥＨＡ構成単位：ＥＡ構成単位：ＭＭＡ構成単位：ＨＥＡ構成単位＝３０：７０：５：５（重量比）（分子量（Ｍｗ＝４５万）））１００重量部と、粘着付与剤（ヤスハラケミカル社製、商品名「マイティーエースＧ１２５」）１０重量部と、イソシアネート系架橋剤（東ソー社製、商品名「コロネートＬ」）２重量部と、熱膨張性微小球（松本油脂製薬社製、商品名「マツモトマイクロスフェア―　Ｆ－１９０Ｄ」）を３０重量部と、トルエンとを混合して得られた粘着剤層形成用組成物を塗工して形成された厚み４５μｍの粘着剤層である。 The "subduction amount of the adhesive sheet in a 23 ° C environment using TMA" is determined after 60 minutes have passed by bringing the probe into contact with the adhesive layer (first adhesive layer) using a thermomechanical analyzer. Means the amount of subduction. The measurement conditions are probe: needle insertion, nitrogen gas flow rate: 50.0 ml / min, and indentation load: 0.01 N. Further, when the pressure-sensitive adhesive sheet has the pressure-sensitive adhesive layer only on one side of the base material (that is, when the pressure-sensitive adhesive layer does not have the second pressure-sensitive adhesive layer described later), the pressure-sensitive adhesive layer of the base material (first pressure-sensitive adhesive layer) and the case where the pressure-sensitive adhesive sheet has the pressure-sensitive adhesive layer. After forming a standard pressure-sensitive adhesive layer on the opposite surface, the above measurements are made. The standard pressure-sensitive adhesive layer is an acrylic copolymer (2-ethylhexyl acrylate (2EHA), ethyl acrylate (EA), methyl methacrylate (MMA) and 2-hydroxyethyl acrylate (HEA) copolymer, 2EHA constituent unit: EA constituent unit: MMA. Constituent unit: HEA Constituent unit = 30: 70: 5: 5 (weight ratio) (molecular weight (Mw = 450,000))) 100 parts by weight and adhesive (Yasuhara Chemical Co., Ltd., trade name "Mighty Ace G125") 10 2 parts by weight, 2 parts by weight of isocyanate-based cross-linking agent (manufactured by Toso Co., Ltd., trade name "Coronate L"), and heat-expandable microspheres (manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd., trade name "Matsumoto Microsphere-F-190D") It is a pressure-sensitive adhesive layer having a thickness of 45 μm formed by applying a composition for forming a pressure-sensitive adhesive layer obtained by mixing 30 parts by weight and toluene.
　粘着シートのＴＭＡを用いた１４５℃環境下における沈み込み量は、好ましくは１μｍ～３５μｍであり、より好ましくは１μｍ～３４μｍであり、さらに好ましくは２μｍ～３４μｍである。このような範囲であれば、本発明の効果は顕著となる。また、高温環境（例えば、樹脂封止の際の加熱処理環境）を経た場合においても、半導体チップの粘着剤層への埋まり込みが防止される。 The amount of subduction of the pressure-sensitive adhesive sheet in an environment of 145 ° C. using TMA is preferably 1 μm to 35 μm, more preferably 1 μm to 34 μm, and further preferably 2 μm to 34 μm. Within such a range, the effect of the present invention becomes remarkable. Further, even when subjected to a high temperature environment (for example, a heat treatment environment at the time of resin encapsulation), embedding of the semiconductor chip in the pressure-sensitive adhesive layer is prevented.
　図３は、本発明の別の実施形態による粘着シートの概略断面図である。粘着シート２００は、基材１０の粘着剤層２０と反対側に、第２の粘着剤層３０をさらに備える。すなわち、粘着シート２００は、粘着剤層２０と、基材１０と、第２の粘着剤層３０とをこの順に備える。第２の粘着剤層３０を備えることにより、台座上で樹脂封止をする際に、第２の粘着剤層３０側を当該台座に貼着して、固定性よく粘着シート２００を配置することができる。 FIG. 3 is a schematic cross-sectional view of an adhesive sheet according to another embodiment of the present invention. The pressure-sensitive adhesive sheet 200 further includes a second pressure-sensitive adhesive layer 30 on the side opposite to the pressure-sensitive adhesive layer 20 of the base material 10. That is, the pressure-sensitive adhesive sheet 200 includes a pressure-sensitive adhesive layer 20, a base material 10, and a second pressure-sensitive adhesive layer 30 in this order. By providing the second pressure-sensitive adhesive layer 30, when the resin is sealed on the pedestal, the second pressure-sensitive adhesive layer 30 side is attached to the pedestal, and the pressure-sensitive adhesive sheet 200 is arranged with good fixing property. Can be done.
　１つの実施形態においては、第２の粘着剤層は、熱膨張性微小球を含む。該熱膨張性微小球は所定温度で膨張し得る。このような熱膨張性微小球を含む粘着剤層は、所定温度以上に加熱することよって熱膨張性微小球が膨張し、粘着面（すなわち第２の粘着剤層表面）に凹凸が生じて、粘着力が低下または消失する。熱膨張性微小球を含む第２の粘着剤層を形成すれば、粘着シートを固定（例えば、台座に固定）する際には必要な粘着性が発現され、粘着シートを剥離する際（例えば、台座から剥離する際）には、加熱により粘着力が低下または消失して、良好な剥離性が発現される。 In one embodiment, the second pressure-sensitive adhesive layer comprises thermally expandable microspheres. The thermally expandable microspheres can expand at a predetermined temperature. In the pressure-sensitive adhesive layer containing such heat-expandable microspheres, the heat-expandable microspheres expand by heating to a predetermined temperature or higher, and the adhesive surface (that is, the surface of the second pressure-sensitive adhesive layer) becomes uneven. Adhesive strength decreases or disappears. By forming a second pressure-sensitive adhesive layer containing the heat-expandable microspheres, the necessary adhesiveness is exhibited when the pressure-sensitive adhesive sheet is fixed (for example, fixed to a pedestal), and when the pressure-sensitive adhesive sheet is peeled off (for example, for example). When peeling from the pedestal), the adhesive strength is reduced or disappears by heating, and good peelability is exhibited.
　本発明の粘着シートは、粘着剤層をポリエチレンテレフタレートに貼着した際の２３℃における粘着力Ａが、好ましくは０．０５Ｎ／２０ｍｍ～１Ｎ／２０ｍｍであり、より好ましくは０．１Ｎ／２０ｍｍ～１０Ｎ／２０ｍｍであり、さらに好ましくは０．１Ｎ／２０ｍｍ～５Ｎ／２０ｍｍであり、特に好ましくは０．２Ｎ／２０ｍｍ～２Ｎ／２０ｍｍであり、最も好ましくは０．２Ｎ／２０ｍｍ～１Ｎ／２０ｍｍである。このような範囲であれば、被着体（例えば、半導体チップ）を好ましく固定し得、かつ、剥離時の糊残りの少ない粘着シートを得ることができる。なお、本明細書において、「粘着剤層をポリエチレンテレフタレートに貼着した際の２３℃における粘着力」とは、ポリエチレンテレフタレートフィルム（厚み２５μｍ）に、粘着シート（幅２０ｍｍ×長さ１４０ｍｍ）の粘着剤層を貼り合わせ（貼り合わせ条件：２ｋｇローラー１往復）、２３℃の環境温度下で３０分間放置した後、該試料を引っ張り試験（剥離速度：３００ｍｍ／ｍｉｎ、剥離角度１８０°）に供して測定される粘着力をいう。 In the pressure-sensitive adhesive sheet of the present invention, the pressure-sensitive adhesive force A at 23 ° C. when the pressure-sensitive adhesive layer is attached to polyethylene terephthalate is preferably 0.05 N / 20 mm to 1 N / 20 mm, more preferably 0.1 N / 20 mm to. It is 10N / 20mm, more preferably 0.1N / 20mm to 5N / 20mm, particularly preferably 0.2N / 20mm to 2N / 20mm, and most preferably 0.2N / 20mm to 1N / 20mm. .. Within such a range, an adherend (for example, a semiconductor chip) can be preferably fixed, and a pressure-sensitive adhesive sheet having less adhesive residue at the time of peeling can be obtained. In the present specification, "adhesive strength at 23 ° C. when the adhesive layer is attached to polyethylene terephthalate" means that an adhesive sheet (width 20 mm x length 140 mm) is adhered to a polyethylene terephthalate film (thickness 25 μm). The agent layers are bonded (bonding conditions: 1 reciprocation of a 2 kg roller), left at an environmental temperature of 23 ° C. for 30 minutes, and then the sample is subjected to a tensile test (peeling speed: 300 mm / min, peeling angle 180 °). Adhesive strength to be measured.
　本発明の粘着シートは、粘着剤層にシリコンチップを貼着した際の１５０℃におけるせん断接着力Ｂが、好ましくは５００ｇ以上であり、より好ましくは７００ｇ～１５００ｇであり、さらに好ましくは８００ｇ～１２００ｇである。このような範囲であれば、粘着剤の凝集力が高く、高温下（例えば、封止樹脂を硬化させるための加熱工程）においても、好ましい粘着力を有し、かつ、粘着シート上に配置された被着体（例えば、半導体チップ）の位置ずれを防止することができる。せん断接着力は、シリコンチップ（サイズ：５ｍｍ×５ｍｍ）のミラー面を粘着剤層にチップ角を当てないように垂直に貼付した後、１３０℃で３０分間加熱してシリコンチップ粘着剤表面に密着させ、その後、測定温度（せん断接着力Ｂ測定の場合、１５０℃）下、せん断速度５００μｍ／ｓｅｃでチップと水平方向に外力を印加することで得られる荷重－変位曲線から、最大破壊荷重を読み取ることにより測定することができる。測定装置としては、例えば、Ｎｏｒｄｓｏｎ社製ｄａｇｅ４０００が用いられる。また、上記測定の際の測定端子は、粘着剤層表面上、高さ２５０μｍの位置とされ得る。 In the pressure-sensitive adhesive sheet of the present invention, the shear adhesive force B at 150 ° C. when the silicon chip is attached to the pressure-sensitive adhesive layer is preferably 500 g or more, more preferably 700 g to 1500 g, and further preferably 800 g to 1200 g. Is. Within such a range, the adhesive has a high cohesive force, has a preferable adhesive force even at a high temperature (for example, a heating step for curing the sealing resin), and is arranged on the adhesive sheet. It is possible to prevent the displacement of the adherend (for example, a semiconductor chip). For shear adhesion, the mirror surface of the silicon chip (size: 5 mm x 5 mm) is attached vertically to the adhesive layer so that the tip angle does not hit, and then heated at 130 ° C. for 30 minutes to adhere to the surface of the silicon chip adhesive. Then, the maximum breaking load is read from the load-displacement curve obtained by applying an external force horizontally to the chip at a shear rate of 500 μm / sec under the measured temperature (150 ° C in the case of shear adhesive force B measurement). This can be measured. As the measuring device, for example, a Dage 4000 manufactured by Nordson is used. Further, the measurement terminal at the time of the above measurement may be located at a height of 250 μm on the surface of the pressure-sensitive adhesive layer.
　本発明の粘着シートは、粘着剤層にシリコンチップを貼着した際の１９０℃におけるせん断接着力が、好ましくは３００ｇ～１０００ｇであり、より好ましくは３５０ｇ～７５０ｇであり、さらに好ましくは４００ｇ～６００ｇである。このような範囲であれば、上記粘着シートが、熱膨張性微小球を含む第２の粘着剤層を備える場合に、該第２の粘着剤層側に剥離性を発現させる際、すなわち、該熱膨張性微小球を膨張させるべく加熱する際に、粘着剤層上の被着体を好ましく固定することができる。 The pressure-sensitive adhesive sheet of the present invention has a shear adhesive force at 190 ° C. when the silicon chip is attached to the pressure-sensitive adhesive layer, preferably 300 g to 1000 g, more preferably 350 g to 750 g, and further preferably 400 g to 600 g. Is. Within such a range, when the pressure-sensitive adhesive sheet includes a second pressure-sensitive adhesive layer containing heat-expandable microspheres, the second pressure-sensitive adhesive layer side exhibits peelability, that is, the said. When the heat-expandable microspheres are heated to expand, the adherend on the pressure-sensitive adhesive layer can be preferably fixed.
　本発明の粘着シートの厚みは、好ましくは３μｍ～３００μｍであり、より好ましくは５μｍ～１５０μｍであり、さらに好ましくは１０μｍ～１００μｍである。 The thickness of the pressure-sensitive adhesive sheet of the present invention is preferably 3 μm to 300 μm, more preferably 5 μm to 150 μm, and further preferably 10 μm to 100 μm.
Ｂ．粘着剤層
　上記粘着剤層は、ベースポリマーを含む粘着剤から構成される。上記のとおり、粘着剤層のパルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）が４５μｓｅｃ以下である。緩和時間とはパルスＮＭＲ測定において、測定対象となる原子を励起するのに適切なエネルギーを照射した後、励起された原子（群）が基底状態に戻るまでの時間を意味する。原子（群）をどのような励起状態にするかは、エネルギー照射の量や時間により制御することができる。また、励起された原子（群）が基底状態に戻るには、様々なエネルギー緩和機構があることが知られており、その緩和機構に応じて緩和時間が決まってくる（例えば、化学者のための最新ＮＭＲ概説、化学同人　（１９９７））。発明者らは、下記条件でアクリル系粘着剤（実質的には、粘着剤に含まれるアクリル系ポリマー）の１Ｈ原子を励起してその後の緩和挙動を計測し、さらに、計測値を解析したところ、その中に、粘着剤層を構成する粘着剤に含まれるベースポリマー（代表的には、アクリル系ポリマー）の架橋の程度に関係する分子運動を知る情報として、Ｔ２緩和時間のＳ成分（Ｔ２ｓ）が有用であることを見いだし、当該Ｔ２緩和時間のＳ成分（Ｔ２ｓ）を特定することにより、上記の効果が得られることを見いだした。Ｔ２ｓが短いことは、ベースポリマーの架橋の程度に関係する分子運動が制限された状態であることを示し、すなわち、架橋が進んでポリマー全体としても運動の自由度が低下した状態であることを示す。このような状態のアクリル系粘着剤においては、ベースポリマー間の隙間が小さく、粘着剤層成分の封止樹脂への移行、および、封止樹脂に含まれる低分子量成分の粘着剤層への移行が抑制される。その結果、半導体チップを粘着シート上で樹脂封止した後、粘着シートを剥離した際に、半導体チップと封止樹脂との段差の発生が防止される。 B. Adhesive layer The adhesive layer is composed of an adhesive containing a base polymer. As described above, the T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is 45 μsec or less. The relaxation time means the time until the excited atom (group) returns to the ground state after irradiating the atom with appropriate energy to excite the atom to be measured in the pulse NMR measurement. The excited state of an atom (group) can be controlled by the amount and time of energy irradiation. It is also known that there are various energy relaxation mechanisms for excited atoms (groups) to return to the ground state, and the relaxation time is determined according to the relaxation mechanism (for example, for chemists). Overview of the latest NMR of the above, Chemistry (1997)). The inventors excited the 1H atom of the acrylic pressure - sensitive adhesive (substantially, the acrylic-based polymer contained in the pressure-sensitive adhesive) under the following conditions, measured the subsequent relaxation behavior, and further analyzed the measured values. However, the S component of the T 2 relaxation time is used as information for knowing the molecular motion related to the degree of cross-linking of the base polymer (typically, an acrylic polymer) contained in the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer. It was found that (T 2s ) is useful, and that the above effect can be obtained by specifying the S component (T 2s ) of the T 2 relaxation time. A short T 2s indicates that the molecular motion related to the degree of cross-linking of the base polymer is restricted, that is, the cross-linking progresses and the degree of freedom of motion of the polymer as a whole is reduced. Is shown. In the acrylic pressure-sensitive adhesive in such a state, the gap between the base polymers is small, and the pressure-sensitive adhesive layer component is transferred to the sealing resin and the low molecular weight component contained in the sealing resin is transferred to the pressure-sensitive adhesive layer. Is suppressed. As a result, when the semiconductor chip is resin-sealed on the pressure-sensitive adhesive sheet and then the pressure-sensitive adhesive sheet is peeled off, the generation of a step between the semiconductor chip and the sealing resin is prevented.
　粘着剤層のパルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）は、好ましくは１０μｓｅｃ～５０μｓｅｃであり、より好ましくは１０μｓｅｃ～４５μｓｅｃであり、さらに好ましくは１０μｓｅｃ～４０μｓｅｃである。このような範囲であれば、上記効果は顕著となる。 The T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is preferably 10 μsec to 50 μsec, more preferably 10 μsec to 45 μsec, and further preferably 10 μsec to 40 μsec. Within such a range, the above effect becomes remarkable.
　パルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）は、粘着剤層１００ｍｇを測定サンプルとして、ソリッドエコー法により測定されたＴ２緩和曲線を得、当該Ｔ２緩和曲線を下記式（１）にフィッテイングして、求めることができる。
 
　　Ｍ（ｔ）＝α・ｅｘｐ（－（１／Ｗａ）（ｔ／Ｔ２ｓ）Ｗａ）
　　　　　　　　　　　＋β・ｅｘｐ（－（１／Ｗａ）（ｔ／Ｔ２Ｌ）Ｗａ）　・・・（１）
　Ｍ（ｔ）：自由誘導減衰
　α：緩和時間が短い成分（Ｓ成分）のプロトン比率（％）
　Ｔ２ｓ：Ｓ成分のＴ２緩和時間（ｍｓｅｃ）
　β：緩和時間が長い成分（Ｌ成分）のプロトン比率（％）
　Ｔ２Ｌ：Ｌ成分のＴ２緩和時間（ｍｓｅｃ）
　ｔ：観測時間（ｍｓｅｃ）
　Ｗａ：形状係数（＝１）
　上記測定における測定条件は、以下のとおりである。
・９０°パルス幅：２．１μｓｅｃ
・繰り返し時間　：１ｓｅｃ
・積算回数　　　：３２回
・測定温度　　　：３０℃ For the T 2 relaxation time (T 2s ) of the S component by pulse NMR, a T 2 relaxation curve measured by the solid echo method was obtained using 100 mg of the pressure-sensitive adhesive layer as a measurement sample, and the T 2 relaxation curve was calculated by the following equation (1). You can find it by fitting it to.

M (t) = α · exp (-(1 / Wa) (t / T 2s ) Wa )
+ Β ・ exp (-(1 / Wa) (t / T 2L ) Wa ) ・ ・ ・ (1)
M (t): Free induction decay α: Proton ratio (%) of component (S component) with short relaxation time
T 2s : T 2 relaxation time (msec) of S component
β: Proton ratio (%) of the component (L component) with a long relaxation time
T 2L : T 2 relaxation time (msec) of L component
t: Observation time (msec)
Wa: Shape coefficient (= 1)
The measurement conditions in the above measurement are as follows.
90 ° pulse width: 2.1 μsec
・ Repeat time: 1 sec
・ Number of integrations: 32 times ・ Measurement temperature: 30 ° C
　上記粘着剤層表面に、４－ターシャリーブチルフェニルグリシジルエーテルを滴下し、１分間静置した後の当該粘着剤層の厚み変化率は、好ましくは１６０％以下であり、より好ましくは１５０％以下であり、さらに好ましくは１２０％以下であり、特に好ましくは１００％以下である。当該厚み変化率がこのような範囲の粘着剤層は、架橋密度が高く、粘着剤層／封止樹脂間における成分移行が防止され、その結果、半導体チップを粘着シート上で樹脂封止した後、粘着シートを剥離した際に、半導体チップと封止樹脂との段差の発生が防止される。上記厚み変化率は、小さいほど好ましいが、その下限は、例えば、２０％（好ましく１０％）である。上記厚み変化率（および、後述の厚み変化量）は、例えば、アクリル系粘着剤に含まれるベースポリマー（代表的には、アクリル系ポリマー）を好ましく選択することにより、上記範囲とすることができる。例えば、炭素数の多い（例えば、４以上、好ましくは８以上）アクリル系ポリマーを用いることにより、厚み変化率（および、後述の厚み変化量）の小さい粘着剤層を形成することができる。上記厚み変化率は、粘着剤層の表面に４－ターシャリーブチルフェニルグリシジルエーテルを所定量（２２ｍｍ径のシリンジを用いて、０．０２ｇ）滴下し、２３℃５０％ＲＨの環境下で１分間放置し、４－ターシャリーブチルフェニルグリシジルエーテルを拭き取った後の、当該滴下箇所の厚み（Ｄｔ）と、上記滴下操作前の当該箇所の厚み（Ｉｔ）とから、（Ｄｔ－Ｉｔ）／Ｉｔの式により求められる。 The rate of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is preferably 160% or less, more preferably 150% or less. It is more preferably 120% or less, and particularly preferably 100% or less. The pressure-sensitive adhesive layer having a thickness change rate in such a range has a high crosslink density and prevents component transfer between the pressure-sensitive adhesive layer and the sealing resin, and as a result, after the semiconductor chip is resin-sealed on the pressure-sensitive adhesive sheet. When the adhesive sheet is peeled off, the generation of a step between the semiconductor chip and the sealing resin is prevented. The smaller the thickness change rate is, the more preferable it is, but the lower limit thereof is, for example, 20% (preferably 10%). The thickness change rate (and the thickness change amount described later) can be set in the above range by preferably selecting, for example, a base polymer (typically, an acrylic polymer) contained in an acrylic pressure-sensitive adhesive. .. For example, by using an acrylic polymer having a large number of carbon atoms (for example, 4 or more, preferably 8 or more), a pressure-sensitive adhesive layer having a small thickness change rate (and a thickness change amount described later) can be formed. The thickness change rate is as follows: 4-tertiary butylphenylglycidyl ether is added dropwise to the surface of the pressure-sensitive adhesive layer in a predetermined amount (0.02 g using a syringe having a diameter of 22 mm) at 23 ° C. and 50% RH for 1 minute. From the thickness (Dt) of the dropping point after leaving and wiping off the 4-tertiary butylphenylglycidyl ether and the thickness (It) of the dropping point before the dropping operation, (Dt-It) / It It is calculated by the formula.
　上記粘着剤層表面に、４－ターシャリーブチルフェニルグリシジルエーテルを滴下し、１分間静置した後の当該粘着剤層の厚み変化量は、好ましくは２０μｍ以下であり、より好ましくは１５μｍ以下であり、さらに好ましくは１０μｍ以下であり、特に好ましくは６μｍ以下である。当該厚み変化量がこのような範囲の粘着剤層は、架橋密度が高く、粘着剤層／封止樹脂間における成分移行が防止され、その結果、半導体チップを粘着シート上で樹脂封止した後、粘着シートを剥離した際に、半導体チップと封止樹脂との段差の発生が防止される。上記厚み変化量は、小さいほど好ましいが、その下限は、例えば、３μｍ（好ましく１μｍ）である。上記厚み変化量は、上記ＤｔとＩｔとから、Ｄｔ－Ｉｔの式により求められる。 The amount of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is preferably 20 μm or less, more preferably 15 μm or less. It is more preferably 10 μm or less, and particularly preferably 6 μm or less. The pressure-sensitive adhesive layer having a thickness change in such a range has a high crosslink density and prevents component transfer between the pressure-sensitive adhesive layer and the sealing resin, and as a result, after the semiconductor chip is resin-sealed on the pressure-sensitive adhesive sheet. When the adhesive sheet is peeled off, the generation of a step between the semiconductor chip and the sealing resin is prevented. The smaller the thickness change amount, the more preferable, but the lower limit thereof is, for example, 3 μm (preferably 1 μm). The thickness change amount is obtained from the above Dt and It by the formula of Dt-It.
　上記粘着剤層のゲル分率は、好ましくは７５％以上であり、より好ましくは８５％以上であり、さらに好ましくは９０％以上である。このような範囲であれば、架橋によりベースポリマーの分子運動が好ましく制限され、粘着剤層／封止樹脂間における成分移行が防止された粘着剤層を得ることができる。粘着剤層のゲル分率は、高いほど好ましいが、その上限は、例えば９９．５％である。なお、ゲル分率は、架橋した粘着剤を酢酸エチルに７日間浸漬した後に乾燥し、（浸漬後の乾燥重量／浸漬前の乾燥重量）×１００で求められる。 The gel fraction of the pressure-sensitive adhesive layer is preferably 75% or more, more preferably 85% or more, and further preferably 90% or more. Within such a range, the molecular motion of the base polymer is preferably restricted by cross-linking, and a pressure-sensitive adhesive layer in which component transfer between the pressure-sensitive adhesive layer and the sealing resin is prevented can be obtained. The higher the gel fraction of the pressure-sensitive adhesive layer is, the more preferable it is, but the upper limit thereof is, for example, 99.5%. The gel fraction is determined by immersing the crosslinked pressure-sensitive adhesive in ethyl acetate for 7 days and then drying it (dry weight after immersion / dry weight before immersion) × 100.
　上記粘着剤層を加熱処理した際の窒素ガスの発生量は、好ましくは０．０６重量％～１．０重量％であり、より好ましくは０．０６重量％～０．９重量％である。粘着剤層を加熱処理した際の窒素ガスの発生量がこのような範囲の場合、アクリル系粘着剤は十分に凝集力を発揮しており、封止樹脂の低分子量成分の粘着剤層への移行を抑制することで、粘着剤層成分と封止樹脂成分の混合層を形成せず、半導体チップと封止樹脂の界面に段差が生じにくくなる。粘着剤層を加熱処理した際の窒素ガス量は、粘着剤層を２ｍｇ採取してセラミックボードに入れてミクロ天秤で計量したサンプルについて、熱分解炉８００℃／酸化炉９００℃の条件で加熱して発生した窒素ガスの量を、ＴＮ（微量全窒素分析）装置を用いて求められる。測定の際の諸条件は以下のとおりとされ得る。
・キャリアーガス：Ｏ２（３００ｍＬ／ｍｉｎ）、Ａｒ（３００ｍＬ／ｍｉｎ）
・標準試料：ピリジン／トルエン溶液
・検出器：減圧化学発光検出器
・レンジ：高濃度 The amount of nitrogen gas generated when the pressure-sensitive adhesive layer is heat-treated is preferably 0.06% by weight to 1.0% by weight, and more preferably 0.06% by weight to 0.9% by weight. When the amount of nitrogen gas generated when the pressure-sensitive adhesive layer is heat-treated is within such a range, the acrylic pressure-sensitive adhesive exhibits sufficient cohesive power, and the low-molecular-weight component of the sealing resin is applied to the pressure-sensitive adhesive layer. By suppressing the migration, a mixed layer of the pressure-sensitive adhesive layer component and the sealing resin component is not formed, and a step is less likely to occur at the interface between the semiconductor chip and the sealing resin. For the amount of nitrogen gas when the pressure-sensitive adhesive layer was heat-treated, 2 mg of the pressure-sensitive adhesive layer was collected, placed in a ceramic board, and weighed with a microbalance. The amount of nitrogen gas generated is determined using a TN (trace total nitrogen analysis) device. The conditions for measurement can be as follows.
-Carrier gas: O 2 (300 mL / min), Ar (300 mL / min)
・ Standard sample: Pyridine / toluene solution ・ Detector: Vacuum chemiluminescence detector ・ Range: High concentration
　上記粘着剤層の厚みは、好ましくは１μｍ～５０μｍであり、より好ましくは３μｍ～３０μｍであり、さらに好ましくは５μｍ～２０μｍである。このような範囲であれば、封止工程時の加圧によっても、半導体チップの樹脂への埋まり込みがたい粘着シートを得ることができる。 The thickness of the pressure-sensitive adhesive layer is preferably 1 μm to 50 μm, more preferably 3 μm to 30 μm, and further preferably 5 μm to 20 μm. Within such a range, it is possible to obtain an adhesive sheet that is difficult to embed in the resin of the semiconductor chip even by pressurization during the sealing step.
　上記粘着剤層の２５℃におけるナノインデンテーション法による弾性率は、好ましくは１００ＭＰａ未満であり、より好ましくは０．１ＭＰａ～５０ＭＰａであり、さらに好ましくは０．１ＭＰａ～１０ＭＰａである。このような範囲であれば、適切な粘着力を有する粘着シートを得ることができる。ナノインデンテーション法による弾性率とは、圧子を試料に押し込んだときの、圧子への負荷荷重と押し込み深さとを負荷時、除荷時にわたり連続的に測定し、得られた負荷荷重－押し込み深さ曲線から求められる弾性率をいう。本明細書において、ナノインデンテーション法による弾性率とは、測定条件を荷重：１ｍＮ、負荷・除荷速度：０．１ｍＮ／ｓ、保持時間：１ｓとして上記のように測定した弾性率をいう。 The elastic modulus of the pressure-sensitive adhesive layer at 25 ° C. by the nanoindentation method is preferably less than 100 MPa, more preferably 0.1 MPa to 50 MPa, and further preferably 0.1 MPa to 10 MPa. Within such a range, an adhesive sheet having an appropriate adhesive strength can be obtained. The elastic modulus by the nanoindentation method is the load load-pushing depth obtained by continuously measuring the load on the indenter and the pushing depth when the indenter is pushed into the sample during loading and unloading. The elastic modulus obtained from the curve. In the present specification, the elastic modulus by the nanoindentation method means the elastic modulus measured as described above under the measurement conditions of load: 1 mN, load / unloading speed: 0.1 mN / s, and holding time: 1s.
　上記粘着剤層の２５℃における引っ張り弾性率は、好ましくは１００ＭＰａ未満であり、より好ましくは０．１ＭＰａ～５０ＭＰａであり、さらに好ましくは０．１ＭＰａ～１０ＭＰａである。このような範囲であれば、適切な粘着力を有する粘着シートを得ることができる。なお、引っ張り弾性率は、ＪＩＳ　Ｋ　７１６１：２００８に準じて測定することができる。 The tensile elastic modulus of the pressure-sensitive adhesive layer at 25 ° C. is preferably less than 100 MPa, more preferably 0.1 MPa to 50 MPa, and further preferably 0.1 MPa to 10 MPa. Within such a range, an adhesive sheet having an appropriate adhesive strength can be obtained. The tensile elastic modulus can be measured according to JIS K 7161: 2008.
　上記粘着剤層のプローブタック値は、好ましくは５０Ｎ／５ｍｍφ以上であり、より好ましくは７５Ｎ／５ｍｍφ以上であり、さらに好ましくは１００Ｎ／５ｍｍφ以上である。このような範囲であれば、粘着シート上に配置された被着体（例えば、半導体チップ）の位置ずれを防止することができる。プローブタック値の測定条件は、プローブ加工速度：３０ｍｍ／ｍｉｎ、テスト速度：３０ｍｍ／ｍｉｎ、密着荷重：１００ｇｆ、密着保持時間：１秒、プローブエリア：５ｍｍφＳＵＳとされる。 The probe tack value of the pressure-sensitive adhesive layer is preferably 50 N / 5 mmφ or more, more preferably 75 N / 5 mm φ or more, and further preferably 100 N / 5 mm φ or more. Within such a range, it is possible to prevent misalignment of the adherend (for example, a semiconductor chip) arranged on the adhesive sheet. The measurement conditions for the probe tack value are: probe processing speed: 30 mm / min, test speed: 30 mm / min, adhesion load: 100 gf, adhesion holding time: 1 second, probe area: 5 mmφSUS.
　上記ベースポリマーのｓｐ値は、好ましくは１０（ｃａｌ／ｃｍ３）１／２～３０（ｃａｌ／ｃｍ３）１／２であり、より好ましくは１５（ｃａｌ／ｃｍ３）１／２～２５（ｃａｌ／ｃｍ３）１／２であり、さらに好ましくは１８（ｃａｌ／ｃｍ３）１／２～２０（ｃａｌ／ｃｍ３）１／２である。このような範囲であれば、粘着剤層／封止樹脂間における成分移行が好ましく防止される。 The sp value of the base polymer is preferably 10 (cal / cm 3 ) 1/2 to 30 (cal / cm 3 ) 1/2 , and more preferably 15 (cal / cm 3 ) 1/2 to 25 ( It is cal / cm 3 ) 1/2 , and more preferably 18 (cal / cm 3 ) 1/2 to 20 (cal / cm 3 ) 1/2 . Within such a range, component transfer between the pressure-sensitive adhesive layer / the sealing resin is preferably prevented.
（アクリル系粘着剤）
　上記アクリル系粘着剤としては、例えば、（メタ）アクリル酸アルキルエステルの１種または２種以上を単量体成分として用いたアクリル系ポリマー（ホモポリマーまたはコポリマー）をプレポリマーとし、該プレポリマーの架橋体をベースポリマーとするアクリル系粘着剤等が挙げられる。なお、本明細書において、粘着剤層中のアクリル系粘着剤に含まれる「ベースポリマー」とは、プレポリマー（未架橋ポリマー）を架橋させて形成されたポリマーを意味する。１つの実施形態においては、上記ベースポリマーは、アクリル系ポリマーとエポキシ架橋剤による架橋体構造を有する。 (Acrylic adhesive)
As the acrylic pressure-sensitive adhesive, for example, an acrylic polymer (homopolymer or copolymer) using one or more (meth) acrylic acid alkyl esters as a monomer component is used as a prepolymer, and the prepolymer is used. Examples thereof include acrylic pressure-sensitive adhesives using a crosslinked polymer as a base polymer. In the present specification, the "base polymer" contained in the acrylic pressure-sensitive adhesive in the pressure-sensitive adhesive layer means a polymer formed by cross-linking a prepolymer (uncrosslinked polymer). In one embodiment, the base polymer has a crosslinked structure of an acrylic polymer and an epoxy crosslinker.
　上記（メタ）アクリル酸アルキルエステルの具体例としては、（メタ）アクリル酸メチル、（メタ）アクリル酸エチル、（メタ）アクリル酸プロピル、（メタ）アクリル酸イソプロピル、（メタ）アクリル酸ブチル、（メタ）アクリル酸イソブチル、（メタ）アクリル酸ｓ－ブチル、（メタ）アクリル酸ｔ－ブチル、（メタ）アクリル酸ペンチル、（メタ）アクリル酸ヘキシル、（メタ）アクリル酸ヘプチル、（メタ）アクリル酸オクチル、（メタ）アクリル酸２－エチルヘキシル、（メタ）アクリル酸イソオクチル、（メタ）アクリル酸ノニル、（メタ）アクリル酸イソノニル、（メタ）アクリル酸デシル、（メタ）アクリル酸イソデシル、（メタ）アクリル酸ウンデシル、（メタ）アクリル酸ドデシル、（メタ）アクリル酸トリデシル、（メタ）アクリル酸テトラデシル、（メタ）アクリル酸ペンタデシル、（メタ）アクリル酸ヘキサデシル、（メタ）アクリル酸ヘプタデシル、（メタ）アクリル酸オクタデシル、（メタ）アクリル酸ノナデシル、（メタ）アクリル酸エイコシル等の（メタ）アクリル酸Ｃ１－２０アルキルエステルが挙げられる。なかでも好ましくは、炭素数が４～２０（より好ましくは６～２０、特に好ましくは８～１８）の直鎖状もしくは分岐状のアルキル基を有する（メタ）アクリル酸アルキルエステルであり、より好ましくは（メタ）アクリル酸２－エチルヘキシルである。 Specific examples of the above (meth) acrylic acid alkyl ester include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, propyl (meth) acrylic acid, isopropyl (meth) acrylic acid, and butyl (meth) acrylic acid. Isobutyl (meth) acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, (meth) acrylate Octyl, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, (meth) acrylic Undecyl acid, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, (meth) acrylate Examples thereof include (meth) acrylic acid C1-20 alkyl esters such as octadecyl, nonadecil (meth) acrylic acid, and eicosyl (meth) acrylic acid. Of these, a (meth) acrylic acid alkyl ester having a linear or branched alkyl group having 4 to 20 carbon atoms (more preferably 6 to 20, particularly preferably 8 to 18) is more preferable. Is 2-ethylhexyl (meth) acrylate.
　１つの実施形態においては、炭素数が４以上（好ましくは、８以上）の直鎖状もしくは分岐状のアルキル基を有する（メタ）アクリル酸アルキルエステルが用いられる。（メタ）アクリル酸アルキルエステルを用いれば、粘着剤層／封止樹脂間における成分移行が好ましく防止される。 In one embodiment, a (meth) acrylic acid alkyl ester having a linear or branched alkyl group having 4 or more carbon atoms (preferably 8 or more carbon atoms) is used. When the (meth) acrylic acid alkyl ester is used, the component transfer between the pressure-sensitive adhesive layer / the sealing resin is preferably prevented.
　上記アクリル系ポリマー（プレポリマー）は、凝集力、耐熱性、架橋性等の改質を目的として、必要に応じて、上記（メタ）アクリル酸アルキルエステルと共重合可能な他の単量体成分に対応する単位を含んでいてもよい。このような単量体成分として、例えば、アクリル酸、メタクリル酸、カルボキシエチルアクリレート、カルボキシペンチルアクリレート、イタコン酸、マレイン酸、フマル酸、クロトン酸等のカルボキシル基含有モノマー；無水マレイン酸、無水イコタン酸等の酸無水物モノマー；（メタ）アクリル酸ヒドロキシエチル、（メタ）アクリル酸ヒドロキシプロピル、（メタ）アクリル酸ヒドロキシブチル、（メタ）アクリル酸ヒドロキシヘキシル、（メタ）アクリル酸ヒドロキシオクチル、（メタ）アクリル酸ヒドロキシデシル、（メタ）アクリル酸ヒドロキシラウリル、（４－ヒドロキシメチルシクロヘキシル）メチルメタクリレート等のヒドロキシル基含有モノマー；スチレンスルホン酸、アリルスルホン酸、２－（メタ）アクリルアミド－２－メチルプロパンスルホン酸、（メタ）アクリルアミドプロパンスルホン酸、スルホプロピル（メタ）アクリレート、（メタ）アクリロイルオキシナフタレンスルホン酸等のスルホン酸基含有モノマー；（メタ）アクリルアミド、Ｎ，Ｎ－ジメチル（メタ）アクリルアミド、Ｎ－ブチル（メタ）アクリルアミド、Ｎ－メチロール（メタ）アクリルアミド、Ｎ－メチロールプロパン（メタ）アクリルアミド等の（Ｎ－置換）アミド系モノマー；（メタ）アクリル酸アミノエチル、（メタ）アクリル酸Ｎ，Ｎ－ジメチルアミノエチル、（メタ）アクリル酸ｔ－ブチルアミノエチル等の（メタ）アクリル酸アミノアルキル系モノマー；（メタ）アクリル酸メトキシエチル、（メタ）アクリル酸エトキシエチル等の（メタ）アクリル酸アルコキシアルキル系モノマー；Ｎ－シクロヘキシルマレイミド、Ｎ－イソプロピルマレイミド、Ｎ－ラウリルマレイミド、Ｎ－フェニルマレイミド等のマレイミド系モノマー；Ｎ－メチルイタコンイミド、Ｎ－エチルイタコンイミド、Ｎ－ブチルイタコンイミド、Ｎ－オクチルイタコンイミド、Ｎ－２－エチルヘキシルイタコンイミド、Ｎ－シクロヘキシルイタコンイミド、Ｎ－ラウリルイタコンイミド等のイタコンイミド系モノマー；Ｎ－（メタ）アクリロイルオキシメチレンスクシンイミド、Ｎ－（メタ）アクルロイル－６－オキシヘキサメチレンスクシンイミド、Ｎ－（メタ）アクリロイル－８－オキシオクタメチレンスクシンイミド等のスクシンイミド系モノマー；酢酸ビニル、プロピオン酸ビニル、Ｎ－ビニルピロリドン、メチルビニルピロリドン、ビニルピリジン、ビニルピペリドン、ビニルピリミジン、ビニルピペラジン、ビニルピラジン、ビニルピロール、ビニルイミダゾール、ビニルオキサゾール、ビニルモルホリン、Ｎ－ビニルカルボン酸アミド類、スチレン、α－メチルスチレン、Ｎ－ビニルカプロラクタム等のビニル系モノマー；アクリロニトリル、メタクリロニトリル等のシアノアクリレートモノマー；（メタ）アクリル酸グリシジル等のエポキシ基含有アクリル系モノマー；（メタ）アクリル酸ポリエチレングリコール、（メタ）アクリル酸ポリプロピレングリコール、（メタ）アクリル酸メトキシエチレングリコール、（メタ）アクリル酸メトキシポリプロピレングリコール等のグリコール系アクリルエステルモノマー；（メタ）アクリル酸テトラヒドロフルフリル、フッ素（メタ）アクリレート、シリコーン（メタ）アクリレート等の複素環、ハロゲン原子、ケイ素原子等を有するアクリル酸エステル系モノマー；ヘキサンジオールジ（メタ）アクリレート、（ポリ）エチレングリコールジ（メタ）アクリレート、（ポリ）プロピレングリコールジ（メタ）アクリレート、ネオペンチルグリコールジ（メタ）アクリレート、ペンタエリスリトールジ（メタ）アクリレート、トリメチロールプロパントリ（メタ）アクリレート、ペンタエリスリトールトリ（メタ）アクリレート、ジペンタエリスリトールヘキサ（メタ）アクリレート、エポキシアクリレート、ポリエステルアクリレート、ウレタンアクリレート等の多官能モノマー；イソプレン、ブタジエン、イソブチレン等のオレフィン系モノマー；ビニルエーテル等のビニルエーテル系モノマー等が挙げられる。これらの単量体成分は、単独で、または２種以上組み合わせて用いてもよい。 The acrylic polymer (prepolymer) is another monomer component that can be copolymerized with the (meth) acrylic acid alkyl ester, if necessary, for the purpose of modifying the cohesiveness, heat resistance, crosslinkability and the like. It may contain the unit corresponding to. Examples of such monomer components include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride and icotanic acid anhydride. Acid anhydride monomers such as (meth) hydroxyethyl acrylate, (meth) hydroxypropyl acrylate, (meth) hydroxybutyl acrylate, (meth) hydroxyhexyl acrylate, (meth) hydroxyoctyl acrylate, (meth) Hydroxyl group-containing monomers such as hydroxydecyl acrylate, hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) methylmethacrylate; styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid. , (Meta) acrylamide propanesulfonic acid, sulfopropyl (meth) acrylate, (meth) acrylic acid group-containing monomers such as oxynaphthalene sulfonic acid; (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-butyl (N-substituted) amide-based monomers such as (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (meth) acrylamide; aminoethyl (meth) acrylate, N, N-dimethyl (meth) acrylate. Aminoalkyl (meth) acrylate monomers such as aminoethyl, t-butylaminoethyl (meth) acrylate; alkoxyalkyl (meth) acrylate such as methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate. Monomer; Maleimide-based monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-phenylmaleimide; N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide , N-2-ethylhexylitaconimide, N-cyclohexylitaconimide, N-laurylitaconimide and other itaconeimide-based monomers; Succinimide-based monomers such as N- (meth) acryloyl-8-oxyoctamethylene succinimide; vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrro Vinyls such as lidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazin, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinylmorpholin, N-vinylcarboxylic acid amides, styrene, α-methylstyrene, N-vinylcaprolactam Monomer; Cyanoacrylate monomer such as acrylonitrile and methacrylonitrile; Epoxy group-containing acrylic monomer such as glycidyl (meth) acrylate; Polyethylene glycol (meth) acrylate, Polypropylene glycol (meth) acrylate, (meth) acrylic acid Glycol-based acrylic ester monomers such as methoxyethylene glycol and methoxypolypropylene glycol (meth) acrylate; heterocycles such as tetrahydrofurfuryl (meth) acrylate, fluorine (meth) acrylate and silicone (meth) acrylate, halogen atoms, and silicon atoms. Acrylic acid ester-based monomers having such factors: hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol. Polyfunctional monomers such as di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy acrylate, polyester acrylate, urethane acrylate; isoprene, butadiene, Olefin-based monomers such as isobutylene; vinyl ether-based monomers such as vinyl ether and the like can be mentioned. These monomer components may be used alone or in combination of two or more.
　１つの実施形態においては、上記アクリル系ポリマー（プレポリマー）は、ホモポリマーとしたときにガラス転移温度（Ｔｇ）が－５℃～１５０℃（好ましくは５０℃～１５０℃、より好ましくは８０℃～１２０℃）となるモノマー由来の構成単位ａをさらに含む。このような構成単位ａを含んでいれば、アクリル系ポリマーの分子運動が制限され、パルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）が好ましく調整されたアクリル系ポリマーを得ることができる。また、低温粘着性に優れる粘着シートを得ることができる。上記構成単位ａの含有量は、アクリル系ポリマーを構成する全構成単位に対して、好ましくは０．１重量％～２０重量％であり、より好ましくは１重量％～１０重量％であり、特に好ましは１．５重量％～８重量％であり、最も好ましくは３重量％～６重量％である。 In one embodiment, the acrylic polymer (prepolymer) has a glass transition temperature (Tg) of −5 ° C. to 150 ° C. (preferably 50 ° C. to 150 ° C., more preferably 80 ° C.) when homopolymerized. It further contains a constituent unit a derived from a monomer (~ 120 ° C.). If such a structural unit a is included, the molecular motion of the acrylic polymer is restricted, and an acrylic polymer in which the T 2 relaxation time (T 2s ) of the S component by pulse NMR is preferably adjusted can be obtained. In addition, an adhesive sheet having excellent low-temperature adhesiveness can be obtained. The content of the structural unit a is preferably 0.1% by weight to 20% by weight, more preferably 1% by weight to 10% by weight, particularly, with respect to all the structural units constituting the acrylic polymer. It is preferably 1.5% by weight to 8% by weight, and most preferably 3% by weight to 6% by weight.
　ガラス転移温度（Ｔｇ）が－５℃～１５０℃となるモノマーとしては、例えば、２‐ヒドロキシエチルアクリレート（Ｔｇ：－３℃）、２－ヒドロキシエチルメタクリレート（Ｔｇ：７７℃）、アクリル酸（Ｔｇ：１０２℃）、メタクリル酸シクロヘキシル（Ｔｇ：８３℃）、アクリル酸ジシクロペンタニル（Ｔｇ：１２０℃）、メタクリル酸ジシクロペンタニル（Ｔｇ：１７５℃）、アクリル酸イソボルニル（Ｔｇ：９４℃）、メタクリル酸イソボルニル（Ｔｇ：１５０℃）、メタクリル酸ｔ－ブチル（Ｔｇ：１１８℃）、メタクリル酸メチル（Ｔｇ：１０５℃）、スチレン（Ｔｇ：８０℃）、アクリルニトリル（Ｔｇ：９７℃）、Ｎ－アクリロイルモルホリン（Ｔｇ：１４５℃）等が挙げられる。中でもメタクリル酸メチルは粘着剤層の透明性を高めるため、加工時の被着体視認性を高める場合には好ましく、また、アクリル酸は分子間相互作用により強く被着体に粘着するため強粘着を必要とする際に好ましく、ヒドロキシエチルアクリレートは多様な架橋剤と高い反応性を示すため、緩和時間制御には一層好ましい。 Examples of the monomer having a glass transition temperature (Tg) of -5 ° C to 150 ° C include 2-hydroxyethyl acrylate (Tg: -3 ° C), 2-hydroxyethyl methacrylate (Tg: 77 ° C), and acrylic acid (Tg). : 102 ° C.), Cyclohexyl methacrylate (Tg: 83 ° C.), Dicyclopentanyl acrylate (Tg: 120 ° C.), Dicyclopentanyl methacrylate (Tg: 175 ° C.), Isobornyl acrylate (Tg: 94 ° C.) , Isobornyl methacrylate (Tg: 150 ° C), t-butyl methacrylate (Tg: 118 ° C), methyl methacrylate (Tg: 105 ° C), styrene (Tg: 80 ° C), acrylic nitrile (Tg: 97 ° C), Examples thereof include N-acryloylmorpholine (Tg: 145 ° C.). Among them, methyl methacrylate is preferable for improving the visibility of the adherend during processing because it enhances the transparency of the pressure-sensitive adhesive layer, and acrylic acid is strongly adhered to the adherend due to the interaction between molecules. Hydroxyethyl acrylate is more preferable for controlling the relaxation time because it exhibits high reactivity with various cross-linking agents.
　１つの実施形態においては、上記アクリル系ポリマー（プレポリマー）は、ヒドロキシル基含有モノマー由来の構成単位をさらに含む。ヒドロキシル基含有モノマー由来の構成単位の含有量は、アクリル系ポリマーを構成する全構成単位に対して、好ましくは０．１重量％～２０重量％であり、より好ましくは０．５重量％～１０重量％であり、特に好ましは１重量％～７重量％である。 In one embodiment, the acrylic polymer (prepolymer) further contains a structural unit derived from a hydroxyl group-containing monomer. The content of the structural unit derived from the hydroxyl group-containing monomer is preferably 0.1% by weight to 20% by weight, more preferably 0.5% by weight to 10% by weight, based on all the structural units constituting the acrylic polymer. It is% by weight, and particularly preferred is 1% by weight to 7% by weight.
　上記アクリル系粘着剤は、必要に応じて、任意の適切な添加剤を含み得る。該添加剤としては、例えば、架橋剤、粘着付与剤、可塑剤（例えば、トリメリット酸エステル系可塑剤、ピロメリット酸エステル系可塑剤等）、顔料、染料、充填剤、老化防止剤、導電材、帯電防止剤、紫外線吸収剤、光安定剤、剥離調整剤、軟化剤、界面活性剤、難燃剤、酸化防止剤等が挙げられる。 The acrylic pressure-sensitive adhesive may contain any suitable additive, if necessary. Examples of the additive include a cross-linking agent, a tackifier, a plasticizer (for example, a trimellitic acid ester-based plasticizer, a pyromellitic acid ester-based plasticizer, etc.), a pigment, a dye, a filler, an antiaging agent, and a conductive material. Examples thereof include materials, antistatic agents, ultraviolet absorbers, light stabilizers, release modifiers, softeners, surfactants, flame retardants, antioxidants and the like.
　上記アクリル系粘着剤に含まれる架橋剤としては、例えば、イソシアネート系架橋剤、エポキシ系架橋剤、メラミン系架橋剤、過酸化物系架橋剤の他、尿素系架橋剤、金属アルコキシド系架橋剤、金属キレート系架橋剤、金属塩系架橋剤、カルボジイミド系架橋剤、オキサゾリン系架橋剤、アジリジン系架橋剤、アミン系架橋剤などが挙げられる。 Examples of the cross-linking agent contained in the acrylic pressure-sensitive adhesive include an isocyanate-based cross-linking agent, an epoxy-based cross-linking agent, a melamine-based cross-linking agent, a peroxide-based cross-linking agent, a urea-based cross-linking agent, and a metal alkoxide-based cross-linking agent. Examples thereof include a metal chelate-based cross-linking agent, a metal salt-based cross-linking agent, a carbodiimide-based cross-linking agent, an oxazoline-based cross-linking agent, an aziridine-based cross-linking agent, and an amine-based cross-linking agent.
　１つの実施形態においては、アクリル系ポリマー（プレポリマー）のカルボキシル基に対する、架橋剤の配合量は、好ましくは０．０８モル当量～２モル当量であり、より好ましくは０．１モル当量～１モル当量である。このような範囲であれば、架橋密度が高いアクリル系粘着剤を形成することでき、粘着剤層／封止樹脂間における成分移行が好ましく防止される。ここでの架橋剤の配合量とは、アクリル系ポリマーが架橋する前の架橋剤の含有量を意味する。 In one embodiment, the amount of the cross-linking agent compounded with respect to the carboxyl group of the acrylic polymer (prepolymer) is preferably 0.08 molar equivalent to 2 molar equivalent, and more preferably 0.1 molar equivalent to 1. It is a molar equivalent. Within such a range, an acrylic pressure-sensitive adhesive having a high crosslink density can be formed, and component transfer between the pressure-sensitive adhesive layer and the sealing resin is preferably prevented. The blending amount of the cross-linking agent here means the content of the cross-linking agent before the acrylic polymer is cross-linked.
　上記アクリル系粘着剤に含まれる上記イソシアネート系架橋剤の具体例としては、ブチレンジイソシアネート、ヘキサメチレンジイソシアネート等の低級脂肪族ポリイソシアネート類；シクロペンチレンジイソシアネート、シクロへキシレンジイソシアネート、イソホロン　ジイソシアネート等の脂環族イソシアネート類；２，４－トリレンジイソシアネート、４，４’－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イソシアネート類；トリメチロールプロパン／トリレンジイソシアネート３量体付加物（日本ポリウレタン工業社製、商品名「コロネートＬ」）、トリメチロールプロパン／へキサメチレンジイソシアネート３量体付加物（日本ポリウレタン工業社製、商品名「コロネートＨＬ」）、ヘキサメチレンジイソシアネートのイソシアヌレート体（日本ポリウレタン工業社製、商品名「コロネートＨＸ」）等のイソシアネート付加物；等が挙げられる。イソシアネート系架橋剤の配合量は、所望とする粘着力に応じて、任意の適切な量に設定され得、アクリル系ポリマー１００重量部に対して、代表的には０．１重量部～２０重量部であり、より好ましくは１重量部～１０重量部である。このような範囲であれば、粘着剤層中の成分の残存カルボキシル基が少ない粘着シートを得ることができる。ここでの架橋剤の配合量とは、アクリル系ポリマーが架橋する前の架橋剤の含有量を意味する。 Specific examples of the isocyanate-based cross-linking agent contained in the acrylic pressure-sensitive adhesive include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate. Group Isocyanates; Aromatic isocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate; Trimethylol propane / tolylene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., Commodity) Name "Coronate L"), Trimethylol propane / hexamethylene diisocyanate trimeric adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "Coronate HL"), isocyanurate form of hexamethylene diisocyanate (manufactured by Japan Polyurethane Industry Co., Ltd., product) Isocyanate adducts such as the name "Coronate HX"); and the like. The blending amount of the isocyanate-based cross-linking agent can be set to an arbitrary appropriate amount according to the desired adhesive strength, and is typically 0.1 part by weight to 20 parts by weight with respect to 100 parts by weight of the acrylic polymer. Parts, more preferably 1 part by weight to 10 parts by weight. Within such a range, a pressure-sensitive adhesive sheet having a small amount of residual carboxyl groups of the components in the pressure-sensitive adhesive layer can be obtained. The blending amount of the cross-linking agent here means the content of the cross-linking agent before the acrylic polymer is cross-linked.
　１つの実施形態においては、上記架橋剤として、エポキシ系架橋剤が好ましく用いられる。エポキシ系架橋剤を用いれば、半導体チップと封止樹脂との段差を好ましく低減し得る粘着シートを得ることができる。また、凝集力が高い粘着剤層を形成することができ、被着体の位置ずれをより有効に防止することができる。 In one embodiment, an epoxy-based cross-linking agent is preferably used as the cross-linking agent. If an epoxy-based cross-linking agent is used, a pressure-sensitive adhesive sheet capable of preferably reducing the step between the semiconductor chip and the sealing resin can be obtained. In addition, it is possible to form a pressure-sensitive adhesive layer having a high cohesive force, and it is possible to more effectively prevent the displacement of the adherend.
　上記アクリル系粘着剤に含まれる前記エポキシ系架橋剤としては、例えば、Ｎ，Ｎ，Ｎ’，Ｎ’－テトラグリシジル－ｍ－キシレンジアミン、ジグリシジルアニリン、１，３－ビス（Ｎ，Ｎ－グリシジルアミノメチル）シクロヘキサン（三菱ガス化学社製、商品名「テトラッドＣ」）、１，６－ヘキサンジオールジグリシジルエーテル（共栄社化学社製、商品名「エポライト１６００」）、ネオペンチルグリコールジグリシジルエーテル（共栄社化学社製、商品名「エポライト１５００ＮＰ」）、エチレングリコールジグリシジルエーテル（共栄社化学社製、商品名「エポライト４０Ｅ」）、プロピレングリコールジグリシジルエーテル（共栄社化学社製、商品名「エポライト７０Ｐ」）、ポリエチレングリコールジグリシジルエーテル（日本油脂社製、商品名「エピオールＥ－４００」）、ポリプロピレングリコールジグリシジルエーテル（日本油脂社製、商品名「エピオールＰ－２００」）、ソルビトールポリグリシジルエーテル（ナガセケムテックス社製、商品名「デナコール　ＥＸ－６１１」）、グリセロールポリグリシジルエーテル（ナガセケムテックス社製、商品名「デナコール　ＥＸ－３１４」）、ペンタエリスリトールポリグリシジルエーテル、ポリグリセロールポリグリシジルエーテル（ナガセケムテックス社製、商品名「デナコール　ＥＸ－５１２」）、ソルビタンポリグリシジルエーテル、トリメチロールプロパンポリグリシジルエーテル、アジピン酸ジグリシジルエステル、ｏ－フタル酸ジグリシジルエステル、トリグリシジル－トリス（２－ヒドロキシエチル）イソシアヌレート、レゾルシンジグリシジルエーテル、ビスフェノール－Ｓ－ジグリシジルエーテル、分子内にエポキシ基を２つ以上有するエポキシ系樹脂等が挙げられる。エポキシ系架橋剤の配合量は、所望とする粘着力に応じて、任意の適切な量に設定され得、アクリル系ポリマー１００重量部に対して、代表的には０．０１重量部～５０重量部であり、より好ましくは０．６重量部～１５重量部であり、さらに好ましくは２重量部～１３重量部であり、特に好ましくは３重量部～１０重量部である。である。このような範囲であれば、粘着剤層中の成分の残存カルボキシル基が少ない粘着シートを得ることができる。ここでの架橋剤の配合量とは、アクリル系ポリマーが架橋する前の架橋剤の含有量を意味する。 Examples of the epoxy-based cross-linking agent contained in the acrylic-based pressure-sensitive adhesive include N, N, N', N'-tetraglycidyl-m-xylene diamine, diglycidyl aniline, and 1,3-bis (N, N-). Glycidylaminomethyl) cyclohexane (manufactured by Mitsubishi Gas Chemicals, trade name "Tetrad C"), 1,6-hexanediol diglycidyl ether (manufactured by Kyoeisha Chemicals, trade name "Epolite 1600"), neopentyl glycol diglycidyl ether (manufactured by Kyoeisha Chemical Co., Ltd., trade name "Epolite 1600") Kyoeisha Chemical Co., Ltd., trade name "Epolite 1500NP"), ethylene glycol diglycidyl ether (Kyoeisha Chemical Co., Ltd., trade name "Epolite 40E"), propylene glycol diglycidyl ether (Kyoeisha Chemical Co., Ltd., trade name "Epolite 70P") , Polyethylene glycol diglycidyl ether (manufactured by Nippon Yushi Co., Ltd., trade name "Epiol E-400"), Polypropylene glycol diglycidyl ether (manufactured by Nippon Yushi Co., Ltd., trade name "Epiol P-200"), Sorbitol polyglycidyl ether (Nagasechem) Tex Co., Ltd., trade name "Denacol EX-611"), glycerol polyglycidyl ether (manufactured by Nagasechemtex, trade name "Denacol EX-314"), pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether (Nagasechemtex) Made by the company, trade name "Denacol EX-512"), sorbitan polyglycidyl ether, trimethylolpropane polyglycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris (2-hydroxyethyl) isocia Examples thereof include nurate, resorcin diglycidyl ether, bisphenol-S-diglycidyl ether, and epoxy resins having two or more epoxy groups in the molecule. The blending amount of the epoxy-based cross-linking agent can be set to an arbitrary appropriate amount according to the desired adhesive strength, and is typically 0.01 parts by weight to 50 parts by weight with respect to 100 parts by weight of the acrylic polymer. It is, more preferably 0.6 parts by weight to 15 parts by weight, still more preferably 2 parts by weight to 13 parts by weight, and particularly preferably 3 parts by weight to 10 parts by weight. Is. Within such a range, a pressure-sensitive adhesive sheet having a small amount of residual carboxyl groups of the components in the pressure-sensitive adhesive layer can be obtained. The blending amount of the cross-linking agent here means the content of the cross-linking agent before the acrylic polymer is cross-linked.
　１つの実施形態においては、エポキシ系架橋剤として、Ｎ原子を含む架橋剤が用いられる。Ｎ原子を含む架橋剤を用いれば、触媒作用により架橋反応が促進され、粘着剤を高ゲル化させやすい点で有利である。 In one embodiment, a cross-linking agent containing N atoms is used as the epoxy-based cross-linking agent. The use of a cross-linking agent containing N atoms is advantageous in that the cross-linking reaction is promoted by catalytic action and the pressure-sensitive adhesive can be easily gelled.
　上記アクリル系粘着剤に含まれる上記粘着付与剤としては、任意の適切な粘着付与剤が用いられる。粘着付与剤としては、例えば、粘着付与樹脂が用いられる。該粘着付与樹脂の具体例としては、ロジン系粘着付与樹脂（例えば、未変性ロジン、変性ロジン、ロジンフェノール系樹脂、ロジンエステル系樹脂など）、テルペン系粘着付与樹脂（例えば、テルペン系樹脂、テルペンフェノール系樹脂、スチレン変性テルペン系樹脂、芳香族変性テルペン系樹脂、水素添加テルペン系樹脂）、炭化水素系粘着付与樹脂（例えば、脂肪族系炭化水素樹脂、脂肪族系環状炭化水素樹脂、芳香族系炭化水素樹脂（例えば、スチレン系樹脂、キシレン系樹脂など）、脂肪族・芳香族系石油樹脂、脂肪族・脂環族系石油樹脂、水素添加炭化水素樹脂、クマロン系樹脂、クマロンインデン系樹脂など）、フェノール系粘着付与樹脂（例えば、アルキルフェノール系樹脂、キシレンホルムアルデヒド系樹脂、レゾール、ノボラックなど）、ケトン系粘着付与樹脂、ポリアミド系粘着付与樹脂、エポキシ系粘着付与樹脂、エラストマー系粘着付与樹脂などが挙げられる。なかでも好ましくは、ロジン系粘着付与樹脂、テルペン系粘着付与樹脂または炭化水素系粘着付与樹脂（スチレン系樹脂など）である。粘着付与剤は、単独で、または２種以上組み合わせて用いてもよい。上記粘着付与剤の添加量は、ベースポリマー１００重量部に対して、好ましくは５重量部～１００重量部であり、より好ましくは８重量部～５０重量部である。 As the pressure-sensitive adhesive contained in the acrylic pressure-sensitive adhesive, any appropriate pressure-sensitive adhesive is used. As the tackifier, for example, a tackifier resin is used. Specific examples of the tackifier resin include rosin-based tackifier resins (eg, unmodified rosin, modified rosin, rosinphenol-based resins, rosin ester-based resins, etc.) and terpene-based tackifier resins (eg, terpene-based resins, terpenes). Phenolic resin, styrene-modified terpene resin, aromatic-modified terpene resin, hydrogenated terpene resin), hydrocarbon-based tackifier resin (for example, aliphatic hydrocarbon resin, aliphatic cyclic hydrocarbon resin, aromatic) Phenolic hydrocarbon resins (eg, styrene resins, xylene resins, etc.), aliphatic / aromatic petroleum resins, aliphatic / alicyclic petroleum resins, hydrogenated hydrocarbon resins, kumaron resins, kumaron inden Resin etc.), Phenol-based tackifier resin (for example, alkylphenol-based resin, xyleneformaldehyde-based resin, resole, novolak, etc.), ketone-based tackifier resin, polyamide-based tackifier resin, epoxy-based tackifier resin, elastomer-based tackifier resin And so on. Of these, a rosin-based tackifier resin, a terpene-based tackifier resin, or a hydrocarbon-based tackifier resin (styrene-based resin, etc.) is preferable. The tackifier may be used alone or in combination of two or more. The amount of the tackifier added is preferably 5 parts by weight to 100 parts by weight, and more preferably 8 parts by weight to 50 parts by weight with respect to 100 parts by weight of the base polymer.
　好ましくは、上記粘着付与樹脂として、軟化点またはガラス転移温度（Ｔｇ）の高い樹脂が用いられる。軟化点またはガラス転移温度（Ｔｇ）の高い樹脂を用いれば、高温環境下（例えば、半導体チップ封止時の加工等における高温環境下）においても、高い粘着性を発現し得る粘着剤層を形成することができる。粘着付与剤の軟化点は、好ましくは１００℃～１８０℃であり、より好ましくは１１０℃～１８０℃であり、さらに好ましくは１２０℃～１８０℃である。粘着付与剤のガラス転位温度（Ｔｇ）は、好ましくは１００℃～１８０℃であり、より好ましくは１１０℃～１８０℃であり、さらに好ましくは１２０℃～１８０℃である。 Preferably, as the tackifier resin, a resin having a high softening point or a glass transition temperature (Tg) is used. By using a resin having a high softening point or glass transition temperature (Tg), a pressure-sensitive adhesive layer capable of exhibiting high adhesiveness is formed even in a high-temperature environment (for example, in a high-temperature environment such as processing at the time of encapsulating a semiconductor chip). can do. The softening point of the tackifier is preferably 100 ° C. to 180 ° C., more preferably 110 ° C. to 180 ° C., and even more preferably 120 ° C. to 180 ° C. The glass dislocation temperature (Tg) of the tackifier is preferably 100 ° C. to 180 ° C., more preferably 110 ° C. to 180 ° C., and even more preferably 120 ° C. to 180 ° C.
　好ましくは、上記粘着付与樹脂として、低極性の粘着付与樹脂が用いられる。低極性の粘着付与樹脂を用いれば、封止材料との親和性が低い粘着剤層を形成することができる。低極性の粘着付与樹脂としては、例えば、脂肪族系炭化水素樹脂、脂肪族系環状炭化水素樹脂、芳香族系炭化水素樹脂（例えば、スチレン系樹脂、キシレン系樹脂など）、脂肪族・芳香族系石油樹脂、脂肪族・脂環族系石油樹脂、水素添加炭化水素樹脂当の炭化水素系粘着付与樹脂が挙げられる。なかでも好ましくは、炭素数が５～９である粘着付与剤である。このような粘着付与剤は、低極性であるとともに、アクリル系ポリマーとの相溶性に優れ、広い温度範囲で相分離せず、安定性に優れた粘着剤層を形成することができるからである。 Preferably, a low-polarity tackifier resin is used as the tackifier resin. If a low-polarity tackifier resin is used, a pressure-sensitive adhesive layer having a low affinity with the sealing material can be formed. Examples of the low-polarity tackifier resin include an aliphatic hydrocarbon resin, an aliphatic cyclic hydrocarbon resin, an aromatic hydrocarbon resin (for example, a styrene resin, a xylene resin, etc.), and an aliphatic / aromatic resin. Examples thereof include based petroleum resins, aliphatic / alicyclic petroleum resins, and hydrogenated hydrocarbon resins, which are hydrocarbon-based tackifier resins. Of these, a tackifier having 5 to 9 carbon atoms is preferable. This is because such a pressure-sensitive adhesive has low polarity, is excellent in compatibility with an acrylic polymer, does not undergo phase separation in a wide temperature range, and can form a pressure-sensitive adhesive layer having excellent stability. ..
　上記粘着付与樹脂の酸価は、好ましくは４０以下であり、より好ましくは２０以下であり、さらに好ましくは１０以下である。このような範囲であれば、封止材料との親和性が低い粘着剤層を形成することができる。上記粘着付与樹脂の水酸基価は、好ましくは６０以下であり、より好ましくは４０以下であり、さらに好ましくは２０以下である。このような範囲であれば、封止材料との親和性が低い粘着剤層を形成することができる。 The acid value of the tackifier resin is preferably 40 or less, more preferably 20 or less, and further preferably 10 or less. Within such a range, a pressure-sensitive adhesive layer having a low affinity with the sealing material can be formed. The hydroxyl value of the tackifier resin is preferably 60 or less, more preferably 40 or less, and further preferably 20 or less. Within such a range, a pressure-sensitive adhesive layer having a low affinity with the sealing material can be formed.
Ｃ．基材
　上記基材としては、例えば、樹脂シート、不織布、紙、金属箔、織布、ゴムシート、発泡シート、これらの積層体（特に、樹脂シートを含む積層体）等が挙げられる。樹脂シートを構成する樹脂としては、例えば、ポリエチレンテレフタレート（ＰＥＴ）、ポリエチレンナフタレート（ＰＥＮ）、ポリブチレンテレフタレート（ＰＢＴ）、ポリエチレン（ＰＥ）、ポリプロピレン（ＰＰ）、エチレン－プロピレン共重合体、エチレン－酢酸ビニル共重合体（ＥＶＡ）、ポリアミド（ナイロン）、全芳香族ポリアミド（アラミド）、ポリイミド（ＰＩ）、ポリ塩化ビニル（ＰＶＣ）、ポリフェニレンサルファイド（ＰＰＳ）、フッ素系樹脂、ポリエーテルエーテルケトン（ＰＥＥＫ）等が挙げられる。不織布としては、マニラ麻を含む不織布等の耐熱性を有する天然繊維による不織布；ポリプロピレン樹脂不織布、ポリエチレン樹脂不織布、エステル系樹脂不織布等の合成樹脂不織布等が挙げられる。金属箔としては、銅箔、ステンレス箔、アルミニウム箔等が挙げられる。紙としては、和紙、クラフト紙等が挙げられる。 C. Base material Examples of the base material include resin sheets, non-woven fabrics, papers, metal foils, woven fabrics, rubber sheets, foam sheets, and laminates thereof (particularly, laminates including resin sheets). Examples of the resin constituting the resin sheet include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyethylene (PE), polypropylene (PP), ethylene-propylene copolymer, and ethylene-. Vinyl acetate copolymer (EVA), polyamide (nylon), total aromatic polyamide (aramid), polyimide (PI), polyvinyl chloride (PVC), polyphenylene sulfide (PPS), fluororesin, polyether ether ketone (PEEK) ) Etc. can be mentioned. Examples of the non-woven fabric include non-woven fabrics made of natural fibers having heat resistance such as non-woven fabrics containing Manila hemp; synthetic resin non-woven fabrics such as polypropylene resin non-woven fabrics, polyethylene resin non-woven fabrics and ester resin non-woven fabrics. Examples of the metal foil include copper foil, stainless steel foil, aluminum foil and the like. Examples of paper include Japanese paper and kraft paper.
　１つの実施形態においては、ガラス転移温度（Ｔｇ）が２５℃以上（好ましくは４０℃以上、より好ましくは５０℃以上）の樹脂から構成される樹脂シートが、基材として好ましく用いられる。このような樹脂シートをも散れば、封止工程時の加熱によっても、基材の形状が維持され、半導体チップの樹脂への埋まり込みが防止される。このような樹脂シートを構成する樹脂としては、例えば、ポリエチレンテレフタレート、ポリイミド、ポリエチレンナフタレート等が挙げられる。 In one embodiment, a resin sheet composed of a resin having a glass transition temperature (Tg) of 25 ° C. or higher (preferably 40 ° C. or higher, more preferably 50 ° C. or higher) is preferably used as the base material. If such a resin sheet is also scattered, the shape of the base material is maintained even by heating during the sealing step, and the embedding of the semiconductor chip in the resin is prevented. Examples of the resin constituting such a resin sheet include polyethylene terephthalate, polyimide, polyethylene naphthalate and the like.
　上記基材の厚さは、所望とする強度または柔軟性、ならびに使用目的等に応じて、任意の適切な厚みに設定され得る。基材の厚みは、好ましくは１０００μｍ以下であり、より好ましくは２５μｍ～１０００μｍであり、さらに好ましくは４０μｍ～５００μｍであり、特に好ましくは６０μｍ～３００μｍであり、最も好ましくは８０μｍ～２５０μｍである。１つの実施形態においては、厚みが２５μｍ以上の基材が用いられる。このような基材を用いれば、封止工程時の加圧によっても、基材の形状が維持され、半導体チップの粘着剤層への埋まり込みが防止される。 The thickness of the base material can be set to an arbitrary appropriate thickness depending on the desired strength or flexibility, the purpose of use, and the like. The thickness of the substrate is preferably 1000 μm or less, more preferably 25 μm to 1000 μm, further preferably 40 μm to 500 μm, particularly preferably 60 μm to 300 μm, and most preferably 80 μm to 250 μm. In one embodiment, a substrate having a thickness of 25 μm or more is used. When such a base material is used, the shape of the base material is maintained even by pressurization during the sealing step, and embedding of the semiconductor chip in the pressure-sensitive adhesive layer is prevented.
　１つの実施形態においては、基材の厚みが、粘着シートの総厚に対して、２０％～９０％（好ましくは２０％～８９％、より好ましくは２０％～８８％）である。このような範囲であれば、半導体チップの粘着剤層への埋まり込みが防止される。 In one embodiment, the thickness of the substrate is 20% to 90% (preferably 20% to 89%, more preferably 20% to 88%) with respect to the total thickness of the pressure-sensitive adhesive sheet. Within such a range, the semiconductor chip is prevented from being embedded in the pressure-sensitive adhesive layer.
　上記基材は、表面処理が施されていてもよい。表面処理としては、例えば、コロナ処理、クロム酸処理、オゾン暴露、火炎暴露、高圧電撃暴露、イオン化放射線処理、下塗り剤によるコーティング処理等が挙げられる。 The base material may be surface-treated. Examples of the surface treatment include corona treatment, chromic acid treatment, ozone exposure, flame exposure, high-voltage impact exposure, ionizing radiation treatment, coating treatment with an undercoat agent, and the like.
　上記有機コーティング材料としては、例えば、プラスチックハードコート材料ＩＩ（ＣＭＣ出版、（２００４））に記載される材料が挙げられる。好ましくはウレタン系ポリマー、より好ましくはポリアクリルウレタン、ポリエステルウレタンまたはこれらの前駆体が用いられる。基材への塗工・塗布が簡便であり、かつ、工業的に多種のものが選択でき安価に入手できるからである。該ウレタン系ポリマーは、例えば、イソシアナートモノマーとアルコール性水酸基含有モノマー（例えば、水酸基含有アクリル化合物又は水酸基含有エステル化合物）との反応混合物からなるポリマーである。有機コーティング材料は、任意の添加剤として、ポリアミンなどの鎖延長剤、老化防止剤、酸化安定剤等を含んでいてもよい。有機コーティング層の厚みは特に限定されないが、例えば、０．１μｍ～１０μｍ程度が適しており、０．１μｍ～５μｍ程度が好ましく、０．５μｍ～５μｍ程度がより好ましい。 Examples of the organic coating material include the materials described in Plastic Hard Coat Material II (CMC Publishing, (2004)). Urethane-based polymers are preferably used, and polyacrylic urethane, polyester urethane or precursors thereof are more preferably used. This is because it is easy to apply and apply to the base material, and various types can be industrially selected and obtained at low cost. The urethane-based polymer is, for example, a polymer composed of a reaction mixture of an isocyanato monomer and an alcoholic hydroxyl group-containing monomer (for example, a hydroxyl group-containing acrylic compound or a hydroxyl group-containing ester compound). The organic coating material may contain a chain extender such as polyamine, an antiaging agent, an oxidation stabilizer and the like as arbitrary additives. The thickness of the organic coating layer is not particularly limited, but is preferably about 0.1 μm to 10 μm, preferably about 0.1 μm to 5 μm, and more preferably about 0.5 μm to 5 μm.
Ｄ．第２の粘着剤層
　上記第２の粘着剤層は、任意の適切な粘着剤から構成される粘着剤層であり得る。１つの実施形態においては、上記のとおり、第２の粘着剤層は、熱膨張性微小球をさらに含む。 D. Second Adhesive Layer The second adhesive layer can be an adhesive layer composed of any suitable adhesive. In one embodiment, as described above, the second pressure-sensitive adhesive layer further comprises thermally expandable microspheres.
　上記第２の粘着剤層に含まれる粘着剤は、硬化型粘着剤（例えば、活性エネルギー線硬化型粘着剤）であってもよく、感圧型粘着剤であってもよい。感圧型粘着剤としては、例えば、アクリル系粘着剤、ゴム系粘着剤等が挙げられる。第２の粘着剤層に含まれる粘着剤の詳細は、例えば特開２０１８－００９０５０号公報の記載を参照することができる。当該公報は、その全体の記載が本明細書に参考として援用される。 The pressure-sensitive adhesive contained in the second pressure-sensitive adhesive layer may be a curable pressure-sensitive adhesive (for example, an active energy ray-curable pressure-sensitive adhesive) or a pressure-sensitive pressure-sensitive adhesive. Examples of the pressure-sensitive pressure-sensitive adhesive include an acrylic pressure-sensitive adhesive and a rubber-based pressure-sensitive adhesive. For details of the pressure-sensitive adhesive contained in the second pressure-sensitive adhesive layer, for example, the description in JP-A-2018-909050 can be referred to. The entire description of the publication is incorporated herein by reference.
　上記熱膨張性微小球としては、加熱により膨張または発泡し得る微小球である限りにおいて、任意の適切な熱膨張性微小球を用いることができる。上記熱膨張性微小球としては、例えば、加熱により容易に膨張する物質を、弾性を有する殻内に内包させた微小球が用いられ得る。このような熱膨張性微小球は、任意の適切な方法、例えば、コアセルベーション法、界面重合法等により製造できる。 As the heat-expandable microsphere, any suitable heat-expandable microsphere can be used as long as it is a microsphere that can be expanded or foamed by heating. As the heat-expandable microsphere, for example, a microsphere in which a substance that easily expands by heating is contained in an elastic shell can be used. Such a heat-expandable microsphere can be produced by any suitable method, for example, a core selvation method, an interfacial polymerization method, or the like.
　加熱により容易に膨張する物質としては、例えば、プロパン、プロピレン、ブテン、ノルマルブタン、イソブタン、イソペンタン、ネオペンタン、ノルマルペンタン、ノルマルヘキサン、イソヘキサン、ヘプタン、オクタン、石油エーテル、メタンのハロゲン化物、テトラアルキルシラン等の低沸点液体；熱分解によりガス化するアゾジカルボンアミド；等が挙げられる。 Substances that easily expand by heating include, for example, propane, propylene, butene, normal butane, isobutane, isopentan, neopentane, normalpentane, normal hexane, isohexane, heptane, octane, petroleum ether, methane halides, and tetraalkylsilanes. Low boiling point liquids such as; azodicarboxylic amides gasified by thermal decomposition; and the like.
　上記殻を構成する物質としては、例えば、アクリロニトリル、メタクリロニトリル、α－クロルアクリロニトリル、α－エトキシアクリロニトリル、フマロニトリル等のニトリル単量体；アクリル酸、メタクリル酸、イタコン酸、マレイン酸、フマル酸、シトラコン酸等のカルボン酸単量体；塩化ビニリデン；酢酸ビニル；メチル（メタ）アクリレート、エチル（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、イソボルニル（メタ）アクリレート、シクロヘキシル（メタ）アクリレート、ベンジル（メタ）アクリレート、β－カルボキシエチルアクリレート等の（メタ）アクリル酸エステル；スチレン、α－メチルスチレン、クロロスチレン等のスチレンモノマー；アクリルアミド、置換アクリルアミド、メタクリルアミド、置換メタクリルアミド等のアミド単量体；等から構成されるポリマーが挙げられる。これらの単量体から構成されるポリマーは、ホモポリマーであってもよく、コポリマーであってもよい。該コポリマーとしては、例えば、塩化ビニリデン‐メタクリル酸メチル－アクリロニトリル共重合体、メタクリル酸メチル－アクリロニトリル－メタクリロニトリル共重合体、メタクリル酸メチル－アクリロニトリル共重合体、アクリロニトリル－メタクリロニトリル－イタコン酸共重合体等が挙げられる。 Examples of the substance constituting the shell include nitrile monomers such as acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-ethoxyacrylonitrile, and fumaronitrile; acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid. Carboxylic acid monomers such as citraconic acid; vinylidene chloride; vinyl acetate; methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, (Meta) acrylic acid esters such as isobornyl (meth) acrylates, cyclohexyl (meth) acrylates, benzyl (meth) acrylates and β-carboxyethyl acrylates; styrene monomers such as styrene, α-methylstyrene and chlorostyrene; acrylamides and substituted acrylamides. , Acrylate monomers such as methacrylicamide and substituted methacrylicamide; and the like. The polymer composed of these monomers may be a homopolymer or a copolymer. Examples of the copolymer include vinylidene chloride-methyl methacrylate-acrylonitrile copolymer, methyl methacrylate-acrylonitrile-methacrylonitrile copolymer, methyl methacrylate-acrylonitrile copolymer, and acrylonitrile-methacrylonitrile-itaconic acid. Examples include polymers.
　上記熱膨張性微小球として、無機系発泡剤または有機系発泡剤を用いてもよい。無機系発泡剤としては、例えば、炭酸アンモニウム、炭酸水素アンモニウム、炭酸水素ナトリウム、亜硝酸アンモニウム、水酸化ホウ素ナトリウム、各種アジド類等が挙げられる。また、有機系発泡剤としては、例えば、トリクロロモノフルオロメタン、ジクロロモノフルオロメタン等の塩フッ化アルカン系化合物；アゾビスイソブチロニトリル、アゾジカルボンアミド、バリウムアゾジカルボキシレート等のアゾ系化合物；パラトルエンスルホニルヒドラジド、ジフェニルスルホン－３，３´－ジスルホニルヒドラジド、４，４´－オキシビス（ベンゼンスルホニルヒドラジド）、アリルビス（スルホニルヒドラジド）等のヒドラジン系化合物；ｐ－トルイレンスルホニルセミカルバジド、４，４´－オキシビス（ベンゼンスルホニルセミカルバジド）等のセミカルバジド系化合物；５－モルホリル－１，２，３，４－チアトリアゾール等のトリアゾール系化合物；Ｎ，Ｎ´－ジニトロソペンタメチレンテトラミン、Ｎ，Ｎ´－ジメチル－Ｎ，Ｎ´－ジニトロソテレフタルアミド；等のＮ－ニトロソ系化合物などが挙げられる。 As the heat-expandable microspheres, an inorganic foaming agent or an organic foaming agent may be used. Examples of the inorganic foaming agent include ammonium carbonate, ammonium hydrogencarbonate, sodium hydrogencarbonate, ammonium nitrite, sodium boron hydroxide, various azides and the like. Examples of the organic foaming agent include salt fluoride alkane-based compounds such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarboxylicamide, and barium azodicarboxylate. Hydrazide compounds such as paratoluenesulfonyl hydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxybis (benzenesulfonylhydrazide), allylbis (sulfonylhydrazide); p-toluylenesulfonyl semicarbazide, 4, Semicarbazide compounds such as 4'-oxybis (benzenesulfonyl semicarbazide); triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; N, N'-dinitrosopentamethylenetetramine, N, N' Examples thereof include N-nitroso compounds such as -dimethyl-N, N'-dinitrosoterephthalamide; and the like.
　上記熱膨張性微小球は市販品を用いてもよい。市販品の熱膨張性微小球の具体例としては、松本油脂製薬社製の商品名「マツモトマイクロスフェアー」（グレード：Ｆ－３０、Ｆ－３０Ｄ、Ｆ－３６Ｄ、Ｆ－３６ＬＶ、Ｆ－５０、Ｆ－５０Ｄ、Ｆ－６５、Ｆ－６５Ｄ、ＦＮ－１００ＳＳ、ＦＮ－１００ＳＳＤ、ＦＮ－１８０ＳＳ、ＦＮ－１８０ＳＳＤ、Ｆ－１９０Ｄ、Ｆ－２６０Ｄ、Ｆ－２８００Ｄ）、日本フィライト社製の商品名「エクスパンセル」（グレード：０５３－４０、０３１－４０、９２０－４０、９０９－８０、９３０－１２０）、呉羽化学工業社製「ダイフォーム」（グレード：Ｈ７５０、Ｈ８５０、Ｈ１１００、Ｓ２３２０Ｄ、Ｓ２６４０Ｄ、Ｍ３３０、Ｍ４３０、Ｍ５２０）、積水化学工業社製「アドバンセル」（グレード：ＥＭＬ１０１、ＥＭＨ２０４、ＥＨＭ３０１、ＥＨＭ３０２、ＥＨＭ３０３、ＥＭ３０４、ＥＨＭ４０１、ＥＭ４０３、ＥＭ５０１）等が挙げられる。 Commercially available products may be used for the above-mentioned heat-expandable microspheres. As a specific example of the commercially available heat-expandable microspheres, the trade name "Matsumoto Microsphere" manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd. (grades: F-30, F-30D, F-36D, F-36LV, F-50) , F-50D, F-65, F-65D, FN-100SS, FN-100SSD, FN-180SS, FN-180SSD, F-190D, F-260D, F-2800D) "Expansel" (grades: 053-40, 031-40, 920-40, 909-80, 930-120), "Dieform" manufactured by Kureha Chemical Industry Co., Ltd. (grades: H750, H850, H1100, S2320D, S2640D, M330, M430, M520), "Advancell" manufactured by Sekisui Chemical Co., Ltd. (grades: EML101, EMH204, EHM301, EHM302, EHM303, EM304, EHM401, EM403, EM501) and the like.
　上記熱膨張性微小球の加熱前の粒子径は、好ましくは０．５μｍ～８０μｍであり、より好ましくは５μｍ～４５μｍであり、さらに好ましくは１０μｍ～２０μｍであり、特に好ましくは１０μｍ～１５μｍである。よって、上記熱膨張性微小球の加熱前の粒子サイズを平均粒子径で言えば、好ましくは６μｍ～４５μｍであり、より好ましくは１５μｍ～３５μｍである。上記の粒子径と平均粒子径はレーザー散乱法における粒度分布測定法によって求められる値である。 The particle size of the heat-expandable microspheres before heating is preferably 0.5 μm to 80 μm, more preferably 5 μm to 45 μm, still more preferably 10 μm to 20 μm, and particularly preferably 10 μm to 15 μm. .. Therefore, the particle size of the heat-expandable microspheres before heating is preferably 6 μm to 45 μm, more preferably 15 μm to 35 μm in terms of average particle size. The above particle size and average particle size are values obtained by the particle size distribution measurement method in the laser scattering method.
　上記熱膨張性微小球は、体積膨張率が好ましくは５倍以上、より好ましくは７倍以上、さらに好ましくは１０倍以上となるまで破裂しない適度な強度を有することが好ましい。このような熱膨張性微小球を用いる場合、加熱処理により粘着力を効率よく低下させることができる。 The heat-expandable microspheres preferably have an appropriate strength that does not burst until the coefficient of thermal expansion is preferably 5 times or more, more preferably 7 times or more, and even more preferably 10 times or more. When such a heat-expandable microsphere is used, the adhesive strength can be efficiently reduced by the heat treatment.
　上記粘着剤層における熱膨張性微小球の含有割合は、所望とする粘着力の低下性等に応じて適切に設定し得る。熱膨張性微小球の含有割合は、第２の粘着剤層を形成するベースポリマー１００重量部に対して、例えば１重量部～１５０重量部であり、好ましくは１０重量部～１３０重量部であり、さらに好ましくは２５重量部～１００重量部である。 The content ratio of the heat-expandable microspheres in the pressure-sensitive adhesive layer can be appropriately set according to the desired decrease in adhesive strength and the like. The content of the heat-expandable microspheres is, for example, 1 part by weight to 150 parts by weight, preferably 10 parts by weight to 130 parts by weight, based on 100 parts by weight of the base polymer forming the second pressure-sensitive adhesive layer. More preferably, it is 25 parts by weight to 100 parts by weight.
　上記粘着剤層が熱膨張性微小球を含む場合、熱膨張性微小球が膨張する前（すなわち、加熱前）の粘着剤層の算術表面粗さＲａは、好ましくは５００ｎｍ以下であり、より好ましくは４００ｎｍ以下であり、さらに好ましくは３００ｎｍ以下である。このような範囲であれば、被着体に対する密着性に優れる粘着シートを得ることができる。このように表面平滑性に優れる粘着剤層は、例えば、粘着剤層の厚みを上記範囲とすること、別の粘着剤層を備える場合ははく離ライナーに粘着剤層を塗布し転写すること等により、得ることができる。なお、上記Ａ項で説明したように、本発明の粘着シートが、別の粘着剤層をさらに備える場合、該別の粘着剤層が熱膨張性微小球を含んでいてもよい。別の粘着剤層が熱膨張性微小球を含む場合においても、該粘着剤層の算術表面粗さＲａは上記範囲であることが好ましい。 When the pressure-sensitive adhesive layer contains heat-expandable microspheres, the arithmetic surface roughness Ra of the pressure-sensitive adhesive layer before the heat-expandable microspheres expand (that is, before heating) is preferably 500 nm or less, more preferably. Is 400 nm or less, more preferably 300 nm or less. Within such a range, an adhesive sheet having excellent adhesion to the adherend can be obtained. The pressure-sensitive adhesive layer having excellent surface smoothness can be obtained by, for example, setting the thickness of the pressure-sensitive adhesive layer within the above range, or by applying the pressure-sensitive adhesive layer to a peeling liner and transferring the pressure-sensitive adhesive layer when another pressure-sensitive adhesive layer is provided. ,Obtainable. As described in Section A above, when the pressure-sensitive adhesive sheet of the present invention further comprises another pressure-sensitive adhesive layer, the other pressure-sensitive adhesive layer may contain heat-expandable microspheres. Even when another pressure-sensitive adhesive layer contains heat-expandable microspheres, the arithmetic surface roughness Ra of the pressure-sensitive adhesive layer is preferably in the above range.
　上記粘着剤層が熱膨張性微小球を含む場合、上記粘着剤層は、８０℃における動的貯蔵弾性率が５ｋＰａ～１ＭＰａ（より好ましくは１０ｋＰａ～０．８ＭＰａ）の範囲にあるベースポリマーから構成される粘着剤を含むことが好ましい。このような粘着剤層であれば、加熱前に適度な粘着性を有し、加熱により粘着力が低下しやすい粘着シートを形成し得る。なお、動的貯蔵弾性率は、動的粘弾性測定装置（例えば、レオメトリックス社製の商品名「ＡＲＥＳ」）を用いて、周波数１Ｈｚ、昇温速度１０℃／ｍｉｎの測定条件により測定され得る。 When the pressure-sensitive adhesive layer contains thermally expandable microspheres, the pressure-sensitive adhesive layer is composed of a base polymer having a dynamic storage elastic modulus in the range of 5 kPa to 1 MPa (more preferably 10 kPa to 0.8 MPa) at 80 ° C. It is preferable to include a pressure-sensitive adhesive. With such a pressure-sensitive adhesive layer, it is possible to form a pressure-sensitive adhesive sheet which has an appropriate adhesiveness before heating and whose adhesive strength tends to decrease by heating. The dynamic storage elastic modulus can be measured by using a dynamic viscoelasticity measuring device (for example, trade name "ARES" manufactured by Leometrics Co., Ltd.) under measurement conditions of a frequency of 1 Hz and a heating rate of 10 ° C./min. ..
Ｅ．粘着シートの製造方法
　本発明の粘着シートは、任意の適切な方法により製造することができる。本発明の粘着シートは、例えば、基材上に直接、アクリル系粘着剤を含む組成物を塗工する方法、または任意の適切な基体上にアクリル系粘着剤を含む組成物を塗工し形成された塗工層を基材に転写する方法等が挙げられる。アクリル系粘着剤を含む組成物は、任意の適切な溶媒を含み得る。 E. Method for Producing Adhesive Sheet The adhesive sheet of the present invention can be produced by any suitable method. The pressure-sensitive adhesive sheet of the present invention is formed, for example, by directly applying a composition containing an acrylic pressure-sensitive adhesive onto a substrate, or by applying a composition containing an acrylic-based pressure-sensitive adhesive onto any suitable substrate. Examples thereof include a method of transferring the applied coating layer to a base material. The composition containing the acrylic pressure-sensitive adhesive may contain any suitable solvent.
　熱膨張性微小球を含む粘着剤層を形成する場合、熱膨張性微小球と粘着剤と任意の適切な溶媒とを含む組成物を基材に塗工して、該粘着剤層を形成することができる。あるいは、粘着剤塗工層に、熱膨張性微小球を振りかけた後、ラミネーター等を用いて、該熱膨張性微小球を粘着剤中に埋め込んで、熱膨張性微小球を含む粘着剤層を形成してもよい。 When forming a pressure-sensitive adhesive layer containing heat-expandable microspheres, a composition containing the heat-expandable microspheres, a pressure-sensitive adhesive, and an arbitrary suitable solvent is applied to a substrate to form the pressure-sensitive adhesive layer. be able to. Alternatively, after sprinkling the heat-expandable microspheres on the pressure-sensitive adhesive coating layer, the heat-expandable microspheres are embedded in the pressure-sensitive adhesive using a laminator or the like to form a pressure-sensitive adhesive layer containing the heat-expandable microspheres. It may be formed.
　上記粘着剤および各組成物の塗工方法としては、任意の適切な塗工方法が採用され得る。例えば、塗布した後に乾燥して各層を形成することができる。塗布方法としては、例えば、マルチコーター、ダイコーター、グラビアコーター、アプリケーター等を用いた塗布方法が挙げられる。乾燥方法としては、例えば、自然乾燥、加熱乾燥等が挙げられる。加熱乾燥する場合の加熱温度は、乾燥対象となる物質の特性に応じて、任意の適切な温度に設定され得る。 Any appropriate coating method can be adopted as the coating method of the adhesive and each composition. For example, each layer can be formed by drying after application. Examples of the coating method include a coating method using a multi-coater, a die coater, a gravure coater, an applicator, and the like. Examples of the drying method include natural drying and heat drying. The heating temperature for heat-drying can be set to any suitable temperature depending on the characteristics of the substance to be dried.
　以下、実施例によって本発明を具体的に説明するが、本発明はこれら実施例によって限定されるものではない。実施例における評価方法は以下のとおりである。また、実施例において、特に明記しない限り、「部」および「％」は重量基準である。 Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. The evaluation method in the examples is as follows. Further, in the examples, unless otherwise specified, "parts" and "%" are based on weight.
（１）粘着剤層のパルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）
　Ｂｒｕｋｅｒ社製の商品名「ＴＤ－ＮＭＲ　ｔｈｅ　ｍｉｎｉｓｐｅｃ　ｍｑ２０」を用い、粘着剤層１００ｍｇを測定サンプルとして、ソリッドエコー法により測定されたＴ２緩和曲線を得、当該Ｔ２緩和曲線を下記式（１）にフィッテイングして、粘着剤層のパルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）
を求めた。
 
　　Ｍ（ｔ）＝α・ｅｘｐ（－（１／Ｗａ）（ｔ／Ｔ２ｓ）Ｗａ）
　　　　　　　　　　　＋β・ｅｘｐ（－（１／Ｗａ）（ｔ／Ｔ２Ｌ）Ｗａ）　・・・（１）
　Ｍ（ｔ）：自由誘導減衰
　α：緩和時間が短い成分（Ｓ成分）のプロトン比率（％）
　Ｔ２ｓ：Ｓ成分のＴ２緩和時間（ｍｓｅｃ）
　β：緩和時間が長い成分（Ｌ成分）のプロトン比率（％）
　Ｔ２Ｌ：Ｌ成分のＴ２緩和時間（ｍｓｅｃ）
　ｔ：観測時間（ｍｓｅｃ）
　Ｗａ：形状係数（＝１）
　上記測定における測定条件は、以下のとおりとした。
・９０°パルス幅：２．１μｓｅｃ
・繰り返し時間　：１ｓｅｃ
・積算回数　　　：３２回
・測定温度　　　：３０℃
 
（２）ＴＭＡを用いた２３℃環境下における沈み込み量
　ＴＭＡ　Ｑ４００（ＴＡ－ｉｎｓｔｒｕｍｅｎｔ社製）を用いて、プローブ：針入　窒素ガス流量：５０．０ｍｌ／ｍｉｎ　押し込み荷重：０．０１Ｎ　測定雰囲気温度：２３．０℃　押し込み負荷時間：６０ｍｉｎの条件で、第１の粘着剤層の沈み込み量を計測した。測定はＮ＝５で実施し、これら測定値の中の最大値と最小値を除くＮ＝３の平均値をサンプルの沈み込み量とした。
 
（３）４－ターシャリーブチルフェニルグリシジルエーテル滴下による厚み変化
　粘着剤層の表面に４－ターシャリーブチルフェニルグリシジルエーテルを所定量（２２ｍｍ径のシリンジを用いて、０．０２ｇ）滴下し、２３℃５０％ＲＨの環境下で１分間放置し、４－ターシャリーブチルフェニルグリシジルエーテルを拭き取った後の、当該滴下箇所の厚み（Ｄｔ）と、上記滴下操作前の当該箇所の厚み（Ｉｔ）とから、厚み変化率（（Ｄｔ－Ｉｔ）／Ｉｔ）および厚み変化量（Ｄｔ－Ｉｔ）を求めた。
 
（４）粘着力（対ＰＥＴ）
　粘着シート（幅２０ｍｍ×長さ１４０ｍｍ）の粘着剤層とは反対側の面の全面に、両面接着テープ（日東電工社製、商品名「Ｎｏ．５３１」）を介して、ＳＵＳ３０４板を、２ｋｇハンドローラーを用いて貼着した。
　次いで、粘着剤層の表面全面に、ポリエチレンテレフタレートフィルム（東レ社製、商品名「ルミラーＳ－１０」、厚さ：２５μｍ、幅：３０ｍｍ）を貼着した（温度：２３℃、湿度：６５％、２ｋｇローラー１往復）。
　上記のようにして得られた評価用試料を、引っ張り試験に供した。引っ張り試験機としては、島津製作社製の商品名「島津オートグラフＡＧ－１２０ｋＮ」を用いた。引っ張り試験機に評価用試料をセットした後、２３℃の環境温度下で３０分間放置した後に、引っ張り試験を開始した。引っ張り試験の条件は、剥離角度：１８０°、剥離速度（引っ張り速度）：３００ｍｍ／ｍｉｎとした。上記ＰＥＴフィルムから粘着シートを剥離した時の荷重を測定し、その際の最大荷重を粘着シートの粘着力とした。
 
（５）粘着力（対封止樹脂）
　粘着シート（幅５０ｍｍ×長さ１４０ｍｍ）の第１の粘着剤層上に、型枠（型サイズ：３５ｍｍ×９０ｍｍの長方形、厚み：５６４μｍ）を貼り合せ、型枠内に顆粒状のエポキシ樹脂系封止材（住友ベークライト社製、Ｇ７３０）を、硬化後の樹脂厚みが０．３ｍｍとなるようにまぶした後に、シリコーン処理剥離ライナーを被せ、名庄プレス社製の「油圧成形機ＮＳ－ＶＰＦ－５０」を用いて、温度１４５℃、成形時間６００秒、加圧条件０．３ＭＰａ（３００ｍｍ□のステージサイズ）、真空時間６００秒、真空度－０．１ＭＰａの条件で、封止樹脂を粘着層上で加熱成形した。
　その後、封止樹脂を１５０℃×７時間の加熱環境下のオーブン内でキュアさせた。封止樹脂のキュア完了後、サンプルを２３℃５０％ＲＨ下で２時間静置した後、封止樹脂と第１の粘着剤層が接触している部分を幅２０ｍｍ×長さ８８ｍｍにカットした。
　上記のようにして得られた評価用試料を、引っ張り試験に供した。引っ張り試験機としては、島津製作社製の商品名「島津オートグラフＡＧ－１２０ｋＮ」を用いた。引っ張り試験機に評価用試料をセットした後、２３℃の環境温度下で３０分間放置した後に、引っ張り試験を開始した。引っ張り試験の条件は、剥離角度：１８０°、剥離速度（引っ張り速度）：３００ｍｍ／ｍｉｎとした。上記封止樹脂から粘着シートを剥離した時の荷重を測定し、その際の平均荷重を粘着シートの粘着力とした。
 
（６）半導体チップと封止樹脂との段差
下記に記載する条件で粘着テープの該粘着剤表面上で封止工程を実施し、半導体チップ（Ｓｉチップ）と封止樹脂界面の段差高さ（スタンドオフ）を計測した。
　キャリア：ＳＵＳ製キャリア　２２０ｍｍΦ
　チップ：Ｓｉミラーチップ　７ｍｍ×７ｍｍ×４００μｍ厚み
　ボンディング装置：ＦＣ３０００Ｗ（東レエンジニアリング社製）
　ボンディング条件：下記の通り
　圧着時間：６秒
　圧着圧力：１０Ｎ
　圧着温度：２３℃
　封止設備：ＭＳ－１５０ＨＰ（アピックヤマダ製）
　封止樹脂：Ｇ７３０（住友ベークライト製）
　プレヒート条件：１３０℃×３０秒
　プレヒート～封止開始までの時間：１時間
　封止温度：１４５℃
　バキューム時間：５秒
　封止時間：６００秒
　クランピングフォース：３．６ＭＰａ
　封止厚み：６００μｍ
　封止作業は、以下の手順で実施した。
１）ＳＵＳキャリアに粘着シートを貼付した。
　貼付条件：２３℃雰囲気下　
　貼付シリンダー圧力：０．１ＭＰａ　
　貼付速度：０．５ｍ／ｍｉｎ
　ＳＵＳ貼付面は、第２の粘着剤層外面とした。
　粘着シートが片面テープ（第２の粘着剤層を備えない）場合は、ＰＥＴフィルム厚み３８μｍのシリコーン剥離ライナー（ＭＲＦ３８　三菱化学製）とＰＥＴフィルム厚み７５μｍのシリコーン剥離ライナー（ＰＥＴ－７５－ＳＣＡ０　フジコー製）を用いて作製した基材レスの熱膨張微小球を含有する粘着剤層４８μｍでＳＵＳキャリアと片面テープを固定して評価を実施した。
２）ＳＵＳキャリアに貼付した粘着シートの該粘着剤層上に、Ｓｉミラーチップをボンディング装置を使用してチップを１個配置した。
３）Ｓｉミラーチップを貼り付けた状態のＳＵＳキャリアを所定の時間でプレヒートを実施した。
４）プレヒート後２３℃５０％ＲＨ環境下で１時間静置したのち、所定の封止設備、樹脂、条件にて封止を実施した。封止樹脂は、手でＳＵＳキャリア上に満遍なく散布して、封止作業を実施した。
５）封止作業で得られた積層体をオーブンを用いて１５０℃×４時間加熱硬化を行った。
６）加熱硬化を行った積層体を２３℃５０％ＲＨ環境下で５日間放置した後、この積層体をホットプレート上で加熱し、ＳＵＳキャリアと貼付している粘着剤を発泡剥離させ、ＳＵＳキャリアを分離した。
７）ＳＵＳキャリアを分離した後の積層体から、粘着テープを剥離し封止樹脂とＳｉチップの封止体を得た。
８）この封止樹脂とＳｉチップの封止体の粘着剤と接していた表面のＳｉチップと封止樹脂の界面の段差をレーザー共焦点顕微鏡（ＯＬＳ－４０００　ＯＬＹＭＰＵＳ製）を用いて計測し、封止樹脂とＳｉチップの界面の段差高さを測定した。 (1) T 2 relaxation time (T 2s ) of S component by pulse NMR of the pressure-sensitive adhesive layer
Using the trade name "TD-NMR the minispec mq20" manufactured by Bruker, a T 2 relaxation curve measured by the solid echo method was obtained using a pressure-sensitive adhesive layer of 100 mg as a measurement sample, and the T 2 relaxation curve was obtained by the following formula (1). ), And the T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer.
Asked.

M (t) = α · exp (-(1 / Wa) (t / T 2s ) Wa )
+ Β ・ exp (-(1 / Wa) (t / T 2L ) Wa ) ・ ・ ・ (1)
M (t): Free induction decay α: Proton ratio (%) of component (S component) with short relaxation time
T 2s : T 2 relaxation time (msec) of S component
β: Proton ratio (%) of the component (L component) with a long relaxation time
T 2L : T 2 relaxation time (msec) of L component
t: Observation time (msec)
Wa: Shape coefficient (= 1)
The measurement conditions in the above measurement were as follows.
90 ° pulse width: 2.1 μsec
・ Repeat time: 1 sec
・ Number of integrations: 32 times ・ Measurement temperature: 30 ° C

(2) Subduction amount in a 23 ° C environment using TMA Using TMA Q400 (manufactured by TA-instrument), probe: needle-inserted nitrogen gas flow rate: 50.0 ml / min Push-in load: 0.01N Measurement atmosphere temperature The sinking amount of the first pressure-sensitive adhesive layer was measured under the condition of: 23.0 ° C. pushing load time: 60 min. The measurement was carried out at N = 5, and the average value of N = 3 excluding the maximum and minimum values among these measured values was taken as the subduction amount of the sample.

(3) Change in thickness due to dropping 4-tertiary butyl phenyl glycidyl ether A predetermined amount (0.02 g using a 22 mm diameter syringe) of 4-tertiary butyl phenyl glycidyl ether was dropped on the surface of the pressure-sensitive adhesive layer, and the temperature was 23 ° C. From the thickness (Dt) of the dropping point after leaving for 1 minute in an environment of 50% RH and wiping off the 4-tertiary butylphenylglycidyl ether, and the thickness (It) of the dropping point before the dropping operation. , Thickness change rate ((Dt-It) / It) and thickness change amount (Dt-It) were determined.

(4) Adhesive strength (against PET)
2 kg of SUS304 plate via double-sided adhesive tape (manufactured by Nitto Denko, trade name "No. 531") on the entire surface of the adhesive sheet (width 20 mm x length 140 mm) opposite to the adhesive layer. It was attached using a hand roller.
Next, a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumirror S-10", thickness: 25 μm, width: 30 mm) was attached to the entire surface of the pressure-sensitive adhesive layer (temperature: 23 ° C., humidity: 65%). 2kg roller 1 round trip).
The evaluation sample obtained as described above was subjected to a tensile test. As the tensile tester, the trade name "Shimadzu Autograph AG-120kN" manufactured by Shimadzu Corporation was used. After setting the evaluation sample in the tensile tester, the sample was left at an environmental temperature of 23 ° C. for 30 minutes, and then the tensile test was started. The conditions for the tensile test were a peeling angle of 180 ° and a peeling speed (pulling speed): 300 mm / min. The load when the adhesive sheet was peeled off from the PET film was measured, and the maximum load at that time was taken as the adhesive force of the adhesive sheet.

(5) Adhesive strength (anti-sealing resin)
A mold (mold size: 35 mm x 90 mm rectangle, thickness: 564 μm) is bonded onto the first pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet (width 50 mm × length 140 mm), and a granular epoxy resin system is used in the mold. After sprinkling the sealing material (G730 manufactured by Sumitomo Bakelite Co., Ltd.) so that the resin thickness after curing becomes 0.3 mm, cover it with a silicone-treated release liner, and apply the "hydraulic molding machine NS-VPF" manufactured by Meijo Press Co., Ltd. -50 "is used to adhere the sealing resin under the conditions of temperature 145 ° C., molding time 600 seconds, pressurization condition 0.3 MPa (stage size of 300 mm □), vacuum time 600 seconds, and vacuum degree -0.1 MPa. Heat molded on the layer.
Then, the sealing resin was cured in an oven under a heating environment of 150 ° C. × 7 hours. After the curing of the sealing resin was completed, the sample was allowed to stand at 23 ° C. and 50% RH for 2 hours, and then the portion where the sealing resin and the first adhesive layer were in contact was cut into a width of 20 mm and a length of 88 mm. ..
The evaluation sample obtained as described above was subjected to a tensile test. As the tensile tester, the trade name "Shimadzu Autograph AG-120kN" manufactured by Shimadzu Corporation was used. After setting the evaluation sample in the tensile tester, the sample was left at an environmental temperature of 23 ° C. for 30 minutes, and then the tensile test was started. The conditions for the tensile test were a peeling angle of 180 ° and a peeling speed (pulling speed): 300 mm / min. The load when the adhesive sheet was peeled off from the sealing resin was measured, and the average load at that time was taken as the adhesive force of the adhesive sheet.

(6) Step between the semiconductor chip and the sealing resin The sealing step is carried out on the surface of the adhesive of the adhesive tape under the conditions described below, and the height of the step at the interface between the semiconductor chip (Si chip) and the sealing resin (6) Stand-off) was measured.
Carrier: SUS carrier 220mmΦ
Chip: Si mirror chip 7 mm x 7 mm x 400 μm thickness Bonding device: FC3000W (manufactured by Toray Industries, Ltd.)
Bonding conditions: Crimping time: 6 seconds Crimping pressure: 10N
Crimping temperature: 23 ° C
Sealing equipment: MS-150HP (manufactured by Apic Yamada)
Encapsulating resin: G730 (manufactured by Sumitomo Bakelite)
Preheat conditions: 130 ° C x 30 seconds Time from preheat to the start of sealing: 1 hour Sealing temperature: 145 ° C
Vacuum time: 5 seconds Sealing time: 600 seconds Clamping force: 3.6 MPa
Sealing thickness: 600 μm
The sealing work was carried out according to the following procedure.
1) An adhesive sheet was attached to the SUS carrier.
Pasting conditions: Under an atmosphere of 23 ° C
Sticking cylinder pressure: 0.1MPa
Sticking speed: 0.5m / min
The SUS affixed surface was the outer surface of the second pressure-sensitive adhesive layer.
If the adhesive sheet is a single-sided tape (without a second adhesive layer), a silicone release liner with a PET film thickness of 38 μm (MRF38 Mitsubishi Chemical) and a silicone release liner with a PET film thickness of 75 μm (PET-75-SCA0 made by Fujiko). ) Was used to fix the SUS carrier and the single-sided tape with the pressure-sensitive adhesive layer 48 μm containing the heat-expanding microspheres without the base material, and the evaluation was carried out.
2) One Si mirror chip was placed on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet attached to the SUS carrier using a bonding device.
3) The SUS carrier with the Si mirror chip attached was preheated for a predetermined time.
4) After preheating, the mixture was allowed to stand for 1 hour in a 23 ° C. and 50% RH environment, and then sealed under the specified sealing equipment, resin, and conditions. The sealing resin was sprayed evenly on the SUS carrier by hand to carry out the sealing operation.
5) The laminate obtained by the sealing operation was heat-cured at 150 ° C. for 4 hours using an oven.
6) After the heat-cured laminate was left to stand in a 23 ° C. and 50% RH environment for 5 days, the laminate was heated on a hot plate, and the adhesive attached to the SUS carrier was foamed and peeled off to form SUS. The carrier was separated.
7) The adhesive tape was peeled off from the laminated body after separating the SUS carrier to obtain a sealing resin and a sealing body of Si chips.
8) The step at the interface between the Si chip and the sealing resin on the surface that was in contact with the adhesive of the sealing resin and the sealing body of the Si chip was measured using a laser confocal microscope (OLS-4000 OLYMPUS). The height of the step at the interface between the sealing resin and the Si chip was measured.
［実施例１］
　アクリル系コポリマーＡ（アクリル酸２エチルヘキシルとアクリル酸とのコポリマー、アクリル酸２エチルヘキシル構成単位：アクリル酸構成単位＝９５：５（重量比））１００重量部と、エポキシ系架橋剤（三菱ガス化学社製、商品名「テトラッドＣ」）５重量部と、トルエン１００重量部とを混合し、粘着剤層形成用組成物を調製した。
　該粘着剤層形成用組成物を、基材としてのポリエチレンテレフタレートフィルム（東レ社製、商品名「ルミラーＳ１０」、厚み３８μｍ）の片面に塗工して、基材と第１の粘着剤層（厚み１０μｍ）とから構成される粘着シート（１）を得た。
　この粘着シート（１）のポリエチレンテレフタレートフィルムの第１の粘着剤層とは反対側の面にアクリル系コポリマーＣ（アクリル酸２エチルヘキシルとアクリル酸エチルとメタクリル酸メチルとアクリル酸２ヒドロキシエチルとのコポリマー、アクリル酸２エチルヘキシル構成単位：アクリル酸エチル構成単位：メタクリル酸メチル構成単位：アクリル酸構成単位＝３０：７０：５：４（重量比））１００重量部と、熱膨張性微小球（松本油脂製薬社製、商品名「マツモトマイクロスフェア―　Ｆ－１９０Ｄ」）３０重量部、イソシアネート系架橋剤（東ソー社製、商品名「コロネートＬ」）１．４重量部と、粘着付与剤（ヤスハラケミカル社製、商品名「マイティーエースＧ１２５」）１０重量部と、トルエン１００重量部とを混合し調整した粘着剤層形成用組成物を塗布し、第２の粘着剤層（厚み４５μｍ）を形成し両面粘着シートを得た。 [Example 1]
Acrylic copolymer A (copolymer of 2 ethylhexyl acrylate and acrylic acid, 2 ethylhexyl acrylate constituent unit: acrylic acid constituent unit = 95: 5 (weight ratio)) 100 parts by weight and epoxy-based cross-linking agent (Mitsubishi Gas Chemicals, Inc.) , Trade name "Tetrad C") 5 parts by weight and 100 parts by weight of toluene were mixed to prepare a composition for forming an adhesive layer.
The composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 μm) as a base material, and the base material and the first pressure-sensitive adhesive layer (manufactured by Toray Industries, Inc., thickness 38 μm) are coated. An adhesive sheet (1) composed of a thickness of 10 μm) was obtained.
Acrylic copolymer C (2-ethylhexyl acrylate, ethyl acrylate, methyl methacrylate and 2-hydroxyethyl acrylate) on the surface of the pressure-sensitive adhesive sheet (1) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film. , 2 ethylhexyl acrylate constituent unit: ethyl acrylate constituent unit: methyl methacrylate constituent unit: acrylic acid constituent unit = 30: 70: 5: 4 (weight ratio)) 100 parts by weight and heat-expandable microspheres (Matsumoto oil and fat) 30 parts by weight of Pharmaceutical Co., Ltd., trade name "Matsumoto Microsphere-F-190D"), 1.4 parts by weight of isocyanate-based cross-linking agent (manufactured by Toso Co., Ltd., trade name "Coronate L"), and adhesive (Yasuhara Chemical Co., Ltd.) , Trade name "Mighty Ace G125") 10 parts by weight and 100 parts by weight of toluene are mixed and adjusted to apply a pressure-sensitive adhesive layer forming composition to form a second pressure-sensitive adhesive layer (thickness 45 μm). I got a sheet.
［実施例２］
　アクリル系コポリマーＡ（アクリル酸２エチルヘキシルとアクリル酸とのコポリマー、アクリル酸２エチルヘキシル構成単位：アクリル酸構成単位＝９５：５（重量比））１００重量部と、エポキシ系架橋剤（三菱ガス化学社製、商品名「テトラッドＣ」）５重量部と、粘着付与剤（ヤスハラケミカル社製、商品名「マイティーエースＧ１２５」）１０重量部と、トルエン１００重量部とを混合し、粘着剤層形成用組成物を調製した。
　該粘着剤層形成用組成物を、基材としてのポリエチレンテレフタレートフィルム（東レ社製、商品名「ルミラーＳ１０」、厚み３８μｍ）の片面に塗工して、基材と第１の粘着剤層（厚み１０μｍ）とから構成される粘着シート（２）を得た。
　この粘着シート（２）のポリエチレンテレフタレートフィルムの第１の粘着剤層とは反対側の面に、実施例１と同様にして第２の粘着剤層を形成し、両面粘着シートを得た。 [Example 2]
Acrylic copolymer A (copolymer of 2 ethylhexyl acrylate and acrylic acid, 2 ethylhexyl acrylate constituent unit: acrylic acid constituent unit = 95: 5 (weight ratio)) 100 parts by weight and epoxy-based cross-linking agent (Mitsubishi Gas Chemicals, Inc.) 5 parts by weight of a pressure-sensitive adhesive (manufactured by Yasuhara Chemical Co., Ltd., trade name "Mighty Ace G125") and 100 parts by weight of toluene are mixed to form a pressure-sensitive adhesive layer. The thing was prepared.
The composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 μm) as a base material, and the base material and the first pressure-sensitive adhesive layer (manufactured by Toray Industries, Inc., thickness 38 μm) are coated. An adhesive sheet (2) composed of a thickness of 10 μm) was obtained.
A second pressure-sensitive adhesive layer was formed on the surface of the pressure-sensitive adhesive sheet (2) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film in the same manner as in Example 1 to obtain a double-sided pressure-sensitive adhesive sheet.
［実施例３］
　アクリル系コポリマーＢ（アクリル酸エチルとアクリル酸ブチルとアクリル酸とアクリル酸２ヒドロキシエチルのコポリマー、アクリル酸エチル構成単位：アクリル酸ブチル構成単位：アクリル酸：アクリル酸ヒドロキシエチル構成単位構成単位＝５０：５０：５：０．１（重量比））１００重量部と、エポキシ系架橋剤（三菱ガス化学社製、商品名「テトラッドＣ」）５重量部と、粘着付与剤（ヤスハラケミカル社製、商品名「マイティーエースＧ１２５」）１０重量部と、トルエン１００重量部とを混合し、粘着剤層形成用組成物を調製した。
　該粘着剤層形成用組成物を、基材としてのポリエチレンテレフタレートフィルム（東レ社製、商品名「ルミラーＳ１０」、厚み３８μｍ）の片面に塗工して、基材と第１の粘着剤層（厚み１０μｍ）とから構成される粘着シート（３）を得た。
　この粘着シート（３）のポリエチレンテレフタレートフィルムの第１の粘着剤層とは反対側の面に、実施例１と同様にして第２の粘着剤層を形成し、両面粘着シートを得た。 [Example 3]
Acrylic Copolymer B (Acrylic acid, butyl acrylate, acrylic acid, and dihydroxyethyl acrylate copolymer, ethyl acrylate constituent unit: butyl acrylate constituent unit: acrylate: hydroxyethyl acrylate constituent unit constituent unit = 50: 50: 5: 0.1 (weight ratio)) 100 parts by weight, epoxy-based cross-linking agent (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name "Tetrad C") 5 parts by weight, and tackifier (manufactured by Yasuhara Chemical Co., Ltd., trade name) "Mighty Ace G125") 10 parts by weight and 100 parts by weight of toluene were mixed to prepare a composition for forming a pressure-sensitive adhesive layer.
The composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 μm) as a base material, and the base material and the first pressure-sensitive adhesive layer (manufactured by Toray Industries, Inc., thickness 38 μm) are coated. An adhesive sheet (3) composed of a thickness of 10 μm) was obtained.
A second pressure-sensitive adhesive layer was formed on the surface of the pressure-sensitive adhesive sheet (3) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film in the same manner as in Example 1 to obtain a double-sided pressure-sensitive adhesive sheet.
［実施例４］
　基材として、ポリエチレンテレフタレートフィルム（東レ社製、商品名「ルミラーＳ１０」、厚み１００μｍ）を用いたこと以外は実施例２と同様にして、両面粘着シートを得た。 [Example 4]
A double-sided pressure-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name “Lumilar S10”, thickness 100 μm) was used as a base material.
［比較例１］
　アクリル系コポリマーＣ（アクリル酸２エチルヘキシルとアクリル酸エチルとメタクリル酸メチルとアクリル酸２ヒドロキシエチルとのコポリマー、アクリル酸２エチルヘキシル構成単位：アクリル酸エチル構成単位：メタクリル酸メチル構成単位：アクリル酸２ヒドロキシエチル構成単位＝３０：７０：５：４（重量比））１００重量部と、イソシアネート系架橋剤（東ソー社製、商品名「コロネートＬ」）１．５重量部と、粘着付与剤（ヤスハラケミカル社製、商品名「マイティーエースＧ１２５」）５重量部を、トルエン１００重量部とを混合し、粘着剤層形成用組成物を調製した。
　該粘着剤層形成用組成物を、基材としてのポリエチレンテレフタレートフィルム（東レ社製、商品名「ルミラーＳ１０」、厚み３８μｍ）の片面に塗工して、基材と粘着剤層（厚み１０μｍ）とから構成される粘着シート（４）を得た。
　この粘着シート（４）のポリエチレンテレフタレートフィルムの第１の粘着剤層とは反対側の面に、実施例１と同様にして第２の粘着剤層を形成し、両面粘着シートを得た。 [Comparative Example 1]
Acrylic copolymer C (copolymer of 2ethylhexyl acrylate, ethyl acrylate, methyl methacrylate and 2hydroxyethyl acrylate, 2-ethylhexyl acrylate constituent unit: ethyl acrylate constituent unit: methyl methacrylate constituent unit: 2 hydroxyacrylate Ethyl constituent unit = 30:70: 5: 4 (weight ratio)) 100 parts by weight, isocyanate-based cross-linking agent (manufactured by Toso Co., Ltd., trade name "Coronate L") 1.5 parts by weight, and tackifier (Yasuhara Chemical Co., Ltd.) , Trade name "Mighty Ace G125") 5 parts by weight was mixed with 100 parts by weight of toluene to prepare a composition for forming an adhesive layer.
The composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 μm) as a base material, and the base material and the pressure-sensitive adhesive layer (thickness 10 μm) are coated. An adhesive sheet (4) composed of the above was obtained.
A second pressure-sensitive adhesive layer was formed on the surface of the pressure-sensitive adhesive sheet (4) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film in the same manner as in Example 1 to obtain a double-sided pressure-sensitive adhesive sheet.
［比較例２］
　アクリル系コポリマーＤ（アクリル酸２エチルヘキシルとアクリル酸２ヒドロキシエチルとのコポリマー、アクリル酸２エチルヘキシル構成単位：アクリル酸２ヒドロキシエチル構成単位＝１００：４（重量比））１００重量部と、イソシアネート系架橋剤（東ソー社製、商品名「コロネートＬ」）１．５重量部と、トルエン１００重量部とを混合し、粘着剤層形成用組成物を調製した。
　該粘着剤層形成用組成物を、基材としてのポリエチレンテレフタレートフィルム（東レ社製、商品名「ルミラーＳ１０」、厚み３８μｍ）の片面に塗工して、基材と粘着剤層（厚み１０μｍ）とから構成される粘着シート（５）を得た。
　この粘着シート（５）のポリエチレンテレフタレートフィルムの第１の粘着剤層とは反対側の面に、実施例１と同様にして第２の粘着剤層を形成し、両面粘着シートを得た。 [Comparative Example 2]
Acrylic copolymer D (copolymer of 2ethylhexyl acrylate and 2hydroxyethyl acrylate, 2ethylhexyl acrylate constituent unit: 2 hydroxyethyl acrylate constituent unit = 100: 4 (weight ratio)) 100 parts by weight and isocyanate-based cross-linking A composition for forming a pressure-sensitive adhesive layer was prepared by mixing 1.5 parts by weight of an agent (manufactured by Toso Co., Ltd., trade name "Coronate L") and 100 parts by weight of toluene.
The composition for forming the pressure-sensitive adhesive layer is applied to one side of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., trade name "Lumilar S10", thickness 38 μm) as a base material, and the base material and the pressure-sensitive adhesive layer (thickness 10 μm) are coated. An adhesive sheet (5) composed of the above was obtained.
A second pressure-sensitive adhesive layer was formed on the surface of the pressure-sensitive adhesive sheet (5) opposite to the first pressure-sensitive adhesive layer of the polyethylene terephthalate film in the same manner as in Example 1 to obtain a double-sided pressure-sensitive adhesive sheet.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　１０　　　　　　　基材
　２０　　　　　　　粘着剤層
　３０　　　　　　　第２の粘着剤層
　１００、２００　　粘着シート
　 10 Base material 20 Adhesive layer 30 Second adhesive layer 100, 200 Adhesive sheet

Claims (14)

  1. 　基材と、該基材の少なくとも片側に配置された粘着剤層とを備える粘着シートであって、
    　該粘着剤層が、アクリル系粘着剤を含み、
    　該粘着シートのＴＭＡを用いた２３℃環境下における沈み込み量が、５μｍ以下であり、
    　該粘着剤層のパルスＮＭＲによるＳ成分のＴ２緩和時間（Ｔ２ｓ）が４５μｓｅｃ以下である、
    　粘着シート。     A pressure-sensitive adhesive sheet comprising a base material and a pressure-sensitive adhesive layer arranged on at least one side of the base material.
    The pressure-sensitive adhesive layer contains an acrylic pressure-sensitive adhesive.
    The amount of subduction of the adhesive sheet in an environment of 23 ° C. using TMA is 5 μm or less.
    The T 2 relaxation time (T 2s ) of the S component by pulse NMR of the pressure-sensitive adhesive layer is 45 μsec or less.
    Adhesive sheet.
  2. 　前記粘着剤層表面に、４－ターシャリーブチルフェニルグリシジルエーテルを滴下し、１分間静置した後の該粘着剤層の厚み変化率が、１６０％以下である、請求項１に記載の粘着シート。 The pressure-sensitive adhesive sheet according to claim 1, wherein the thickness change rate of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is 160% or less. ..
  3. 　前記粘着剤層表面に、４－ターシャリーブチルフェニルグリシジルエーテルを滴下し、１分間静置した後の該粘着剤層の厚み変化量が、２０μｍ以下である、請求項１または２に記載の粘着シート。 The pressure-sensitive adhesive according to claim 1 or 2, wherein the amount of change in the thickness of the pressure-sensitive adhesive layer after dropping 4-tertiary butylphenylglycidyl ether onto the surface of the pressure-sensitive adhesive layer and allowing it to stand for 1 minute is 20 μm or less. Sheet.
  4. 　前記粘着剤層が粘着剤を含み、
    　該粘着剤が、ｓｐ値が１８（ｃａｌ／ｃｍ３）１／２～２０（ｃａｌ／ｃｍ３）１／２であるベースポリマーを含む、
    　請求項１から３のいずれかに記載の粘着シート。     The pressure-sensitive adhesive layer contains a pressure-sensitive adhesive.
    The pressure-sensitive adhesive comprises a base polymer having an sp value of 18 (cal / cm 3 ) 1/2 to 20 (cal / cm 3 ) 1/2 .
    The adhesive sheet according to any one of claims 1 to 3.
  5. 　前記アクリル系粘着剤が、ベースポリマーとして、アクリル系ポリマーの架橋体を含む、請求項１から４のいずれかに記載の粘着シート。 The pressure-sensitive adhesive sheet according to any one of claims 1 to 4, wherein the acrylic pressure-sensitive adhesive contains a crosslinked body of the acrylic-based polymer as a base polymer.
  6. 　前記アクリル系粘着剤が、エポキシ系架橋剤を含む、請求項１から５のいずれかに記載の粘着シート。 The pressure-sensitive adhesive sheet according to any one of claims 1 to 5, wherein the acrylic pressure-sensitive adhesive contains an epoxy-based cross-linking agent.
  7. 　前記エポキシ系架橋剤の配合量が、アクリル系ポリマー１００重量部に対して、０．６重量部～１５重量部である、請求項６に記載の粘着シート。 The pressure-sensitive adhesive sheet according to claim 6, wherein the blending amount of the epoxy-based cross-linking agent is 0.6 parts by weight to 15 parts by weight with respect to 100 parts by weight of the acrylic polymer.
  8. 　前記基材が、ガラス転移温度（Ｔｇ）が２５℃以上の樹脂から構成される樹脂シートである、請求項１から７のいずれかに記載の粘着シート。 The pressure-sensitive adhesive sheet according to any one of claims 1 to 7, wherein the base material is a resin sheet composed of a resin having a glass transition temperature (Tg) of 25 ° C. or higher.
  9. 　前記基材の厚みが、粘着シートの総厚に対して、２０％～９０％、である、請求項１から８のいずれかに記載の粘着シート。 The pressure-sensitive adhesive sheet according to any one of claims 1 to 8, wherein the thickness of the base material is 20% to 90% with respect to the total thickness of the pressure-sensitive adhesive sheet.
  10. 　前記粘着シートのＴＭＡを用いた１４５℃環境下における沈み込み量が、１μｍ～３５μｍである、請求項１から９のいずれかに記載の粘着シート。 The pressure-sensitive adhesive sheet according to any one of claims 1 to 9, wherein the amount of the pressure-sensitive adhesive sheet submerged in an environment of 145 ° C. using TMA is 1 μm to 35 μm.
  11. 　前記粘着剤層を加熱処理した際の窒素ガスの発生量が、０．０６重量％～１．０重量％である、請求項１から１０のいずれかに記載の粘着シート。 The pressure-sensitive adhesive sheet according to any one of claims 1 to 10, wherein the amount of nitrogen gas generated when the pressure-sensitive adhesive layer is heat-treated is 0.06% by weight to 1.0% by weight.
  12. 　前記基材と、該基材の片側に配置された前記粘着剤層と、該基材の該粘着剤層とは反対側に配置された第２の粘着剤層とを備える、請求項１から１１のいずれかに記載の粘着シート。 The first aspect of the present invention comprises the base material, the pressure-sensitive adhesive layer arranged on one side of the base material, and the second pressure-sensitive adhesive layer arranged on the side opposite to the pressure-sensitive adhesive layer of the base material. The adhesive sheet according to any one of 11.
  13. 　半導体チップの樹脂封止工程で用いられる仮固定材である、請求項１から１２のいずれかに記載の粘着シート。 The adhesive sheet according to any one of claims 1 to 12, which is a temporary fixing material used in the resin sealing process of a semiconductor chip.
  14. 　前記粘着シート上で、封止樹脂を硬化する際に用いられる、請求項１３に記載の粘着シート。 The pressure-sensitive adhesive sheet according to claim 13, which is used when the sealing resin is cured on the pressure-sensitive adhesive sheet.
PCT/JP2021/039065 2020-12-07 2021-10-22 Adhesive sheet WO2022123932A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
KR1020237011454A KR20230061511A (en) 2020-12-07 2021-10-22 adhesive sheet
CN202180069545.6A CN116368199A (en) 2020-12-07 2021-10-22 Pressure-sensitive adhesive sheet
JP2022568091A JPWO2022123932A1 (en) 2020-12-07 2021-10-22
DE112021005267.5T DE112021005267T5 (en) 2020-12-07 2021-10-22 SELF-ADHESIVE LAYER

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2020-202667 2020-12-07
JP2020202667 2020-12-07

Publications (1)

Publication Number Publication Date
WO2022123932A1 true WO2022123932A1 (en) 2022-06-16

Family

ID=81972872

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2021/039065 WO2022123932A1 (en) 2020-12-07 2021-10-22 Adhesive sheet

Country Status (6)

Country Link
JP (1) JPWO2022123932A1 (en)
KR (1) KR20230061511A (en)
CN (1) CN116368199A (en)
DE (1) DE112021005267T5 (en)
TW (1) TW202233778A (en)
WO (1) WO2022123932A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023286620A1 (en) * 2021-07-13 2023-01-19 日東電工株式会社 Pressure-sensitive adhesive sheet
WO2023286619A1 (en) * 2021-07-13 2023-01-19 日東電工株式会社 Adhesive sheet
WO2023286621A1 (en) * 2021-07-13 2023-01-19 日東電工株式会社 Pressure-sensitive adhesive sheet

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011124495A (en) * 2009-12-14 2011-06-23 Nitto Denko Corp Heat-resistant adhesive tape for sealing resin, and method of manufacturing resin-sealed semiconductor device using the same
JP2012064714A (en) * 2010-09-15 2012-03-29 Nitto Denko Corp Pressure-sensitive adhesive tape for resin seal, and method for manufacturing resin seal-type semiconductor device
JP2012149182A (en) * 2011-01-19 2012-08-09 Nitto Denko Corp Double-sided adhesive tape or sheet, and method for processing adherend
JP2014198830A (en) * 2013-03-29 2014-10-23 日東電工株式会社 Adhesive tape for electrochemical device
JP2015168711A (en) * 2014-03-05 2015-09-28 日東電工株式会社 Pressure sensitive adhesive sheet
JP2019199561A (en) * 2018-05-17 2019-11-21 日東電工株式会社 Adhesive sheet

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4403631B2 (en) 2000-04-24 2010-01-27 ソニー株式会社 Manufacturing method of chip-shaped electronic component and manufacturing method of pseudo wafer used for manufacturing the same
JP2001313350A (en) 2000-04-28 2001-11-09 Sony Corp Chip-shaped electronic component and its manufacturing method, and pseudo-wafer used for manufacture of chip- shaped electronic component and its manufacturing method
JP6783570B2 (en) 2016-07-11 2020-11-11 日東電工株式会社 Adhesive sheet

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011124495A (en) * 2009-12-14 2011-06-23 Nitto Denko Corp Heat-resistant adhesive tape for sealing resin, and method of manufacturing resin-sealed semiconductor device using the same
JP2012064714A (en) * 2010-09-15 2012-03-29 Nitto Denko Corp Pressure-sensitive adhesive tape for resin seal, and method for manufacturing resin seal-type semiconductor device
JP2012149182A (en) * 2011-01-19 2012-08-09 Nitto Denko Corp Double-sided adhesive tape or sheet, and method for processing adherend
JP2014198830A (en) * 2013-03-29 2014-10-23 日東電工株式会社 Adhesive tape for electrochemical device
JP2015168711A (en) * 2014-03-05 2015-09-28 日東電工株式会社 Pressure sensitive adhesive sheet
JP2019199561A (en) * 2018-05-17 2019-11-21 日東電工株式会社 Adhesive sheet

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023286620A1 (en) * 2021-07-13 2023-01-19 日東電工株式会社 Pressure-sensitive adhesive sheet
WO2023286619A1 (en) * 2021-07-13 2023-01-19 日東電工株式会社 Adhesive sheet
WO2023286621A1 (en) * 2021-07-13 2023-01-19 日東電工株式会社 Pressure-sensitive adhesive sheet

Also Published As

Publication number Publication date
JPWO2022123932A1 (en) 2022-06-16
TW202233778A (en) 2022-09-01
DE112021005267T5 (en) 2023-07-20
KR20230061511A (en) 2023-05-08
CN116368199A (en) 2023-06-30

Similar Documents

Publication Publication Date Title
CN105907317B (en) Heat-peelable pressure-sensitive adhesive sheet
WO2022123932A1 (en) Adhesive sheet
JP6378501B2 (en) Adhesive sheet
JP6448333B2 (en) Adhesive sheet
JPWO2005087888A1 (en) Heat-peelable pressure-sensitive adhesive sheet and method for processing an adherend using the heat-peelable pressure-sensitive adhesive sheet
JP6768038B2 (en) Adhesive sheet
JP7133355B2 (en) Adhesive sheet
JP7155210B2 (en) Adhesive sheet
JP2021006634A (en) Adhesive sheet
WO2022123931A1 (en) Adhesive sheet
JP7428473B2 (en) Manufacturing method of electronic components
WO2022185611A1 (en) Adhesive sheet
WO2022153601A1 (en) Pressure-sensitive adhesive sheet
WO2023021773A1 (en) Pressure-sensitive adhesive sheet
WO2023286620A1 (en) Pressure-sensitive adhesive sheet
WO2023286619A1 (en) Adhesive sheet
WO2023286621A1 (en) Pressure-sensitive adhesive sheet
JP2024090083A (en) Adhesive sheet

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21903036

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2022568091

Country of ref document: JP

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 20237011454

Country of ref document: KR

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 21903036

Country of ref document: EP

Kind code of ref document: A1