TWI734893B - Adhesive sheet - Google Patents

Abstract

An adhesive sheet (10), which is an adhesive sheet (10) used to seal semiconductor elements on the adhesive sheet, and has a substrate (11), an adhesive layer (12) containing an adhesive, and an adhesive layer (12) arranged on the substrate (11) The oligomer sealing layer (13) between and the adhesive layer (12).

Description

Adhesive sheet

The present invention relates to adhesive sheets.

Various characteristics are required for adhesive sheets used in the manufacturing steps of semiconductor devices. In recent years, for adhesive sheets, it is required that the devices, components, and adherends used in the manufacturing steps will not be contaminated even after high-temperature conditions are applied. Furthermore, it is also required that when the adhesive sheet is peeled off at room temperature after the step of high temperature conditions, there are few defects (so-called residual glue) of the remaining adhesive on the adherend and the like, and the peeling force is small.

For example, Document 1 (Japanese Patent Application Laid-Open No. 2002-275435) describes the use of suppressing adhesive residues and stably producing QFN (Quad Flat Non-lead) semiconductor package mask sheets. Document 1 describes the use of a specific heat-resistant film and silicone-based adhesive to make a mask sheet that can withstand the die bonding step and the resin sealing step at 150°C to 180°C for 1 hour to 6 hours environment.

In recent years, adhesive sheets have also been used even in steps subject to high temperature conditions such as 180°C or more and 200°C or less. In such a high-temperature step, for example, when a film with lower heat resistance and a lower price such as a polyimide film (such as a film of polyethylene terephthalate) is used as a substrate, it can be known that the When the adhesive body peels off the adhesive sheet, the surface of the adhesive body will be contaminated. The cause of such contamination is believed to be caused by the precipitation of low molecular weight components (oligomers) contained in the resin film used as the base material on the surface of the adherend. For example, when a high temperature condition is applied in the step of resin sealing the semiconductor element attached to the adhesive layer of the adhesive sheet, the surface of the semiconductor element may be contaminated, which may cause problems in the semiconductor device.

The object of the present invention is to provide an adhesive sheet that can prevent the surface of the adherend from being contaminated even after the step of applying high temperature conditions.

According to one aspect of the present invention, there is provided an adhesive sheet, which is an adhesive sheet used to seal semiconductor devices on the adhesive sheet, and has a substrate, an adhesive layer containing an adhesive, and an adhesive layer disposed on the aforementioned substrate and The oligomer sealing layer between the aforementioned adhesive layers.

In the adhesive sheet of one aspect of the present invention, the aforementioned oligomer sealing layer is preferably obtained by curing a composition for an oligomer sealing layer containing an epoxy compound, a polyester compound, and a polyfunctional amine compound Harden the film.

In the adhesive sheet of one aspect of the present invention, the composition for the oligomer sealing layer preferably contains (A) 50% by mass or more and 80% by mass or less of a bisphenol A epoxy compound, and (B) 5 mass% % Or more and 30% by mass or less of polyester compound, and (C) 10% by mass or more and 40% by mass or less of polyfunctional amino compound.

In the adhesive sheet of one aspect of the present invention, the storage modulus of the aforementioned substrate at 100°C is preferably 1×10 ⁷ Pa or more.

In the adhesive sheet of one aspect of the present invention, the adhesive layer preferably contains an acrylic adhesive composition or a silicone adhesive composition.

In the adhesive sheet of one aspect of the present invention, the aforementioned acrylic adhesive composition preferably contains an acrylic copolymer containing 2-ethylhexyl acrylate as the main monomer.

In the adhesive sheet of one aspect of the present invention, the aforementioned silicone adhesive composition preferably contains an addition polymerization type silicone resin.

In the adhesive sheet of one aspect of the present invention, it is preferable to have the oligomer sealing layer on both sides of the substrate.

In the adhesive sheet of one aspect of the present invention, the aforementioned base material preferably contains a polyester resin.

According to the present invention, it is possible to provide an adhesive sheet that can prevent contamination of the surface of the adherend even after the step of applying high temperature conditions.

10、10A‧‧‧Adhesive sheet

11‧‧‧Substrate

11a‧‧‧First substrate surface

11b‧‧‧Second substrate surface

12‧‧‧Adhesive layer

13‧‧‧Oligomer sealing layer

20‧‧‧Frame member

21‧‧‧Opening

30‧‧‧Sealing resin

30A‧‧‧Sealing resin layer

40‧‧‧Reinforcing member

41‧‧‧Reinforcing plate

42‧‧‧Next layer

50‧‧‧Seal body

CP‧‧‧Semiconductor chip

Fig. 1 is a schematic cross-sectional view of the adhesive sheet of the first embodiment.

2A is a diagram illustrating a part of the manufacturing process of the semiconductor device using the adhesive sheet of the first embodiment.

2B is a diagram illustrating a part of the manufacturing process of the semiconductor device using the adhesive sheet of the first embodiment.

2C is a diagram illustrating a part of the manufacturing process of the semiconductor device using the adhesive sheet of the first embodiment.

2D is a diagram illustrating a part of the manufacturing process of the semiconductor device using the adhesive sheet of the first embodiment.

2E is a diagram illustrating a part of the manufacturing process of the semiconductor device using the adhesive sheet of the first embodiment.

Fig. 3 is a schematic cross-sectional view of the adhesive sheet of the second embodiment.

[First Embodiment] (Adhesive sheet)

Fig. 1 shows a schematic cross-sectional view of the adhesive sheet 10 of the present embodiment.

The adhesive sheet 10 has a substrate 11, an adhesive layer 12 and an oligomer sealing layer 13.

The base material 11 has a first base material surface 11a and a second base material surface 11b on the opposite side of the first base material surface 11a. An oligomer sealing layer 13 is provided between the substrate 11 and the adhesive layer 12. In the adhesive sheet 10, it is preferable that the oligomer sealing layer 13 is laminated on the first substrate surface 11 a, and the first substrate surface 11 a is covered by the oligomer sealing layer 13.

The shape of the adhesive sheet 10 may be any shape such as a sheet shape, a tape shape, and a label shape.

(Substrate)

The base material 11 is a member supporting the adhesive layer 12 and the oligomer sealing layer 13.

For the substrate 11, for example, a sheet material such as a synthetic resin film can be used. Examples of synthetic resin films include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, and polyethylene terephthalate. Ester film, polyethylene naphthalate film, polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate copolymer film, ionomer resin film, ethylene/(methyl) Acrylic copolymer film, ethylene/(meth)acrylate copolymer film, polystyrene film, polycarbonate film, polyimide film, etc. In addition, as the base material 11, these crosslinked films, laminated films, and the like can be cited.

The base material 11 preferably contains a polyester-based resin, and more preferably is composed of a material whose main component is a polyester-based resin. In this specification, a material with a polyester resin as the main component means that the proportion of the polyester resin in the total mass of the material constituting the base material is 50% by mass or more.

The polyester resin is preferably selected from, for example, polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate resin, polyethylene naphthalate resin, and Any resin in the group of copolymerized resins of these resins; more preferably a polyethylene terephthalate resin.

The substrate 11 is preferably a polyethylene terephthalate film or a polyethylene naphthalate film; more preferably a polyethylene terephthalate film. The oligomers contained in the polyester film are derived from polyester-forming monomers, dimers, and trimers.

The lower limit of the storage modulus at 100°C of the substrate 11 is preferably 1×10 ⁷ Pa or more, more preferably 1×10 ⁸ Pa or more from the viewpoint of dimensional stability during processing. The upper limit of the storage modulus at 100°C of the substrate 11 is preferably 1×10 ¹² Pa or less from the viewpoint of processability. Furthermore, in this specification, the storage modulus is the value measured by the torsional shear method at a frequency of 1 Hz using a dynamic viscoelasticity measuring device. The measured base material was cut into a width of 5 mm and a length of 20 mm, and a viscoelasticity measuring machine (manufactured by TA Instruments, DMAQ800) was used to measure the storage viscoelasticity at 100°C with a frequency of 1 Hz and a stretching mode.

In order to improve the adhesion to the oligomer sealing layer 13, the first substrate surface 11a may be subjected to at least any surface treatment such as primer treatment, corona treatment, and plasma treatment. On the first substrate surface 11a of the substrate 11, an adhesive can also be applied to perform adhesion treatment. The adhesive used in the adhesion treatment of the substrate includes, for example, acrylic-based, rubber-based, silicone-based, and urethane-based adhesives.

The thickness of the substrate 11 is preferably 10 μm or more and 500 μm or less, more preferably 15 μm or more and 300 μm or less, and still more preferably 20 μm or more and 250 μm or less.

(Adhesive layer)

The adhesive layer 12 of this embodiment contains an adhesive composition. The adhesive contained in the adhesive composition is not particularly limited, and various types of adhesives can be applied to the adhesive layer 12. Examples of the adhesive contained in the adhesive layer 12 include rubber-based, acrylic-based, silicone-based, polyester-based, and urethane-based adhesives. Furthermore, the type of adhesive is selected in consideration of the purpose and the type of adherend to be attached. The adhesive layer 12 preferably contains an acrylic adhesive composition or a silicone adhesive composition.

. Acrylic adhesive composition

When the adhesive layer 12 contains an acrylic adhesive composition, the acrylic adhesive composition preferably contains an acrylic copolymer containing 2-ethylhexyl acrylate as a main monomer.

Moreover, when the adhesive layer 12 contains an acrylic adhesive composition, it is preferable to contain an acrylic copolymer and an adhesive auxiliary agent. The acrylic copolymer is preferably a copolymer containing 2-ethylhexyl acrylate as the main monomer. The adhesion assistant preferably contains a rubber-based material having a reactive group as a main component.

In this specification, using 2-ethylhexyl acrylate as the main monomer means that the mass ratio of the copolymer component derived from 2-ethylhexyl acrylate in the total mass of the acrylic copolymer is 50% by mass or more. In this embodiment, the ratio of the copolymer component derived from 2-ethylhexyl acrylate in the acrylic copolymer is preferably 50% by mass or more and 95% by mass or less, more preferably 60% by mass or more and 95% by mass or less , It is more preferably 80% by mass or more and 95% by mass or less, and still more preferably 85% by mass or more and 93% by mass or less. If the proportion of the copolymer component derived from 2-ethylhexyl acrylate is 50% by mass or more, the adhesive force will not become too high after heating, and it will be easier to peel the adhesive sheet from the adherend, if it is 80% by mass or more It is easier to peel off. If the ratio of the copolymer component derived from 2-ethylhexyl acrylate is 95% by mass or less, it is possible to prevent the initial adhesive force from deforming the substrate during heating due to insufficient initial adhesion, or from peeling the adhesive sheet from the adherend due to the deformation.

In the acrylic copolymer, the type and number of copolymer components other than 2-ethylhexyl acrylate are not particularly limited. For example, as the second copolymer component, a functional group-containing monomer having a reactive functional group is preferred. As the reactive functional group of the second copolymer component, when a crosslinking agent described later is used, it is preferably a functional group that can react with the crosslinking agent. The reactive functional group is preferably, for example, at least any substituent selected from the group consisting of carboxyl group, hydroxyl group, amino group, substituted amino group, and epoxy group; more preferably at least any substituent group of carboxyl group and hydroxyl group ; More preferably, it is a carboxyl group.

Examples of monomers having carboxyl groups (carboxyl group-containing monomers) include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. Among the carboxyl group-containing monomers, acrylic acid is particularly preferred from the viewpoint of reactivity and copolymerization. The carboxyl group-containing monomer may be used alone or in combination of two or more kinds.

Monomers having hydroxyl groups (hydroxyl-containing monomers) include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, ( Hydroxyalkyl (meth)acrylates such as 2-hydroxybutyl meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Among the hydroxyl-containing monomers, 2-hydroxyethyl (meth)acrylate is particularly preferred from the viewpoint of hydroxyl reactivity and copolymerization. The hydroxyl group-containing monomer may be used alone or in combination of two or more kinds. In addition, in this specification, "(meth)acrylic acid" refers to the expression used when both "acrylic acid" and "methacrylic acid" are used, and other similar terms are also the same.

The acrylate having an epoxy group includes, for example, glycidyl acrylate, glycidyl methacrylate, and the like.

Other copolymer components in the acrylic copolymer include alkyl (meth)acrylates with 2-20 carbon atoms in the alkyl group. Alkyl (meth)acrylates, for example, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, n-pentyl (meth)acrylate, (methyl) ) N-hexyl acrylate, 2-ethylhexyl methacrylate, isooctyl (meth)acrylate, n-decyl (meth)acrylate, n-dodecyl (meth)acrylate, (meth) Base) myristyl acrylate, palmityl (meth)acrylate, and stearyl (meth)acrylate. Among these alkyl (meth)acrylates, from the viewpoint of improving adhesion, (meth)acrylates having an alkyl group of 2 to 4 carbon atoms are preferred, and (meth)acrylic acid is more preferred. n-butyl ester. The alkyl (meth)acrylate may be used alone or in combination of two or more kinds.

Other copolymer components in the acrylic copolymer include, for example, (meth)acrylates selected from the group consisting of alkoxyalkyl-containing (meth)acrylates, (meth)acrylates having an aliphatic ring, and (meth)acrylates having an aromatic ring. Acrylate, non-crosslinkable acrylamide, (meth)acrylate with non-crosslinkable tertiary amino group, vinyl acetate, and at least any monomer from the group of styrene Copolymer component.

The (meth)acrylates containing alkoxyalkyl groups include, for example, methoxymethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, And ethoxyethyl (meth)acrylate.

The (meth)acrylate having an aliphatic ring includes, for example, cyclohexyl (meth)acrylate.

The (meth)acrylate having an aromatic ring includes, for example, phenyl (meth)acrylate.

Examples of the non-crosslinkable acrylamide include acrylamide and methacrylamide.

The (meth)acrylates with non-crosslinkable tertiary amino groups include, for example, (N,N-dimethylamino)ethyl (meth)acrylic acid and (N,N-dimethyl)acrylic acid (N,N). -Dimethylamino) propyl ester.

As the other copolymer component in the acrylic copolymer, from the viewpoint of improving the polarity of the adhesive and improving the adhesion and adhesion, it is also preferably a copolymer component derived from a monomer having a ring containing a nitrogen atom.

Monomers having a ring containing nitrogen atoms include N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpiperidone, N-vinylpiperazine, N- Vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinylmorpholine, N-vinylcaprolactam, and N-(meth)acryloylmorpholine, etc. The monomer having a ring containing a nitrogen atom is preferably N-(meth)acryloylmorpholine.

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

In this embodiment, as the second copolymer component, a carboxyl group-containing monomer or a hydroxyl group-containing monomer is preferred, and acrylic acid is more preferred. When the acrylic copolymer contains a copolymer component derived from 2-ethylhexyl acrylate and a copolymer component derived from acrylic acid, the ratio of the copolymer component derived from acrylic acid to the total mass of the acrylic copolymer is preferably 1 % By mass or less, more preferably 0.1% by mass or more and 0.5% by mass or less. If the ratio of acrylic acid is 1% by mass or less, when a crosslinking agent is included in the adhesive composition, the crosslinking of the acrylic copolymer can be prevented from proceeding too quickly.

The acrylic copolymer may also contain copolymer components derived from two or more functional group-containing monomers. For example, the acrylic copolymer may be a ternary copolymer. When the acrylic copolymer is a three-component copolymer, it is preferably an acrylic copolymer obtained by copolymerizing 2-ethylhexyl acrylate, a carboxyl group-containing monomer, and a hydroxyl group-containing monomer. The body is preferably acrylic acid, and the monomer containing hydroxyl group is preferably 2-hydroxyethyl acrylate. In the acrylic copolymer, it is preferable that the ratio of the copolymer component derived from 2-ethylhexyl acrylate is 80% by mass or more and 95% by mass or less, and the ratio of the copolymer component derived from acrylic acid is 1% by mass or less, and The remainder is the copolymer component derived from 2-hydroxyethyl acrylate.

The weight average molecular weight (Mw) of the acrylic copolymer is preferably 300,000 or more and 2 million or less, more preferably 600,000 or more and 1.5 million or less, and still more preferably 800,000 or more and 1.2 million or less. If the weight average molecular weight Mw of the acrylic copolymer is 300,000 or more, it can be peeled without the residue of the adhesive on the adherend. If the weight average molecular weight Mw of the acrylic copolymer is 2 million or less, the adherend can be adhered reliably.

The weight average molecular weight Mw of the acrylic copolymer is a standard polystyrene conversion value measured by the Gel Permeation Chromatography (GPC) method.

Acrylic copolymers can be produced by using the aforementioned various raw material monomers according to conventionally known methods.

The copolymerization form of the acrylic copolymer is not particularly limited, and it can be any of a block copolymer, a random copolymer, or a graft copolymer.

In this embodiment, the content of the acrylic copolymer in the adhesive composition is preferably 40% by mass or more and 90% by mass or less, more preferably 50% by mass or more and 90% by mass or less.

The adhesion promoter preferably contains a rubber-based material having a reactive group as a main component. If the adhesive composition contains a reactive adhesive aid, the residual glue can be reduced. The content of the adhesion assistant in the adhesive composition is preferably 3% by mass or more and 50% by mass or less, more preferably 5% by mass or more and 30% by mass or less. If the content of the adhesion promoter in the adhesive composition is 3% by mass or more, the generation of residual glue can be suppressed, and if it is 50% by mass or less, the decrease in adhesive force can be suppressed.

In this specification, containing a rubber-based material with a reactive group as the main component means that the mass ratio of the rubber-based material with a reactive group in the total mass of the adhesive agent exceeds 50% by mass. In this embodiment, the ratio of the rubber-based material having a reactive group in the adhesion promoter is preferably more than 50% by mass, more preferably 80% by mass or more. It is also preferable that the adhesion promoter is substantially composed of a rubber-based material having a reactive group.

The reactive group is preferably one or more functional groups selected from the group consisting of a hydroxyl group, an isocyanate group, an amino group, an oxirane group, an acid anhydride group, an alkoxy group, an acryl group, and a methacryl group ; More preferably, it is a hydroxyl group. The reactive group possessed by the rubber-based material may be one type or two or more types. The rubber-based material having a hydroxyl group may further have the aforementioned reactive group. In addition, the number of reactive groups may be one or two or more in one molecule constituting the rubber-based material.

The rubber-based material is not particularly limited. Preferably, it is a hydrogenated product of polybutadiene-based resin and polybutadiene-based resin; more preferably, it is a hydrogenated product of polybutadiene-based resin.

Examples of polybutadiene-based resins include resins having 1,4-repeating units, resins having 1,2-repeating units, and resins having both 1,4-repeating units and 1,2-repeating units. The hydrogenated product of the polybutadiene-based resin of this embodiment also includes the hydrogenated product of the resin having these repeating units.

The polybutadiene-based resin and the hydrogenated product of the polybutadiene-based resin preferably have reactive groups at both ends. The reactive groups at the two ends may be the same or different. The reactive groups at both ends are preferably one or more selected from the group consisting of a hydroxyl group, an isocyanate group, an amino group, an oxirane group, an acid anhydride group, an alkoxy group, an acryl group and a methacryl group Functional group; more preferably a hydroxyl group. In polybutadiene-based resins and hydrogenated polybutadiene-based resins, it is more preferable that both ends are hydroxyl groups.

The adhesive composition of the present embodiment also preferably contains a cross-linked product obtained by cross-linking a composition blended with a cross-linking agent in addition to the aforementioned acrylic copolymer and adhesion assistant. In addition, the solid content of the adhesive composition is also preferably substantially composed of a cross-linked product obtained by cross-linking the acrylic copolymer, the adhesion promoter, and the cross-linking agent as described above. Here, in essence, it means that the solid content of the adhesive composition is composed only of the cross-linked product, except for trace impurities inevitably mixed in the adhesive.

In this embodiment, the crosslinking agent includes, for example, an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, an aziridine-based crosslinking agent, a metal clamp-based crosslinking agent, an amine-based crosslinking agent, and an amine-based crosslinking agent. Resin-based crosslinking agent. These crosslinking agents may be used alone or in combination of two or more kinds.

In this embodiment, from the viewpoint of improving the heat resistance and adhesive force of the adhesive composition, among these crosslinking agents, the crosslinking agent containing a compound having an isocyanate group as the main component (isocyanate-based crosslinking Agent) is better. The isocyanate-based crosslinking agent includes, for example, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1,3-xylene diisocyanate, 1,4-xylene diisocyanate, and diphenylmethane-4, 4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4 Polyisocyanate compounds such as'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, and lysine isocyanate.

In addition, the polyisocyanate compound may also be a trimethylolpropane adduct type modified body of the aforementioned compound, a biuret type modified body that reacts with water, or a melamine isocyanate type modified body having a melamine ring body.

In this specification, a crosslinking agent containing a compound having an isocyanate group as a main component means that the mass of the compound having an isocyanate group accounts for 50% by mass or more of the total mass of the components constituting the crosslinking agent.

In this embodiment, the content of the crosslinking agent in the adhesive composition is preferably 0.1 part by mass or more and 20 parts by mass or less, more preferably 1 part by mass or more, relative to 100 parts by mass of the acrylic copolymer. 15 parts by mass or less, and more preferably 5 parts by mass or more and 10 parts by mass or less. If the content of the crosslinking agent in the adhesive composition is within such a range, the adhesion between the layer containing the adhesive composition (adhesive layer) and the adherend (such as the substrate) can be improved, and the adhesive sheet can be shortened The maturation period after manufacturing to stabilize the adhesive properties.

In this embodiment, from the viewpoint of the heat resistance of the adhesive composition, the isocyanate-based crosslinking agent is more preferably a compound having a melamine ring (a melamine type modified body). The compound having a trimeric isocyanate ring is preferably blended in an amount of 0.7 equivalent or more and 1.5 equivalent or less with respect to the hydroxyl equivalent of the acrylic copolymer. If the blending amount of the compound having a trimeric isocyanate ring is 0.7 equivalent or more, the adhesive force will not become too high after heating, it is easy to peel off the adhesive sheet, and the residual glue can be reduced. If the blending amount of the compound having a trimeric isocyanate ring is 1.5 equivalents or less, it is possible to prevent the initial adhesive force from becoming too low or to prevent the adhesiveness from decreasing.

When the adhesive composition in this embodiment contains a crosslinking agent, the adhesive composition preferably further contains a crosslinking accelerator. The crosslinking accelerator is preferably appropriately selected and used according to the kind of crosslinking agent and the like. For example, when the adhesive composition contains a polyisocyanate compound as a crosslinking agent, it is preferable to further contain an organometallic compound-based crosslinking accelerator such as an organotin compound.

. Polysiloxane adhesive composition

When the adhesive layer 12 contains a silicone adhesive composition, the silicone adhesive composition preferably contains an addition polymerization type silicone resin. In this specification, the silicone adhesive composition containing the addition polymerization type silicone resin is referred to as the addition reaction type silicone adhesive composition.

The addition reaction type silicone adhesive composition contains a main agent and a crosslinking agent. The addition reaction type silicone adhesive composition has the advantage that it can be cured only once at low temperature and does not need to be cured twice at high temperature. Incidentally, the conventional peroxide-curing silicone adhesives must be cured twice at a high temperature of 150°C or higher.

Therefore, by using the addition reaction type silicone adhesive composition, the adhesive sheet can be manufactured at a lower temperature, with excellent energy efficiency, and the substrate 11 with lower heat resistance can also be used to manufacture the adhesive sheet 10. In addition, it does not produce by-products during curing like peroxide-curing silicone adhesives, so there is no problem of odor and corrosion.

The addition reaction type silicone adhesive composition usually consists of: a main agent composed of a mixture of silicone resin components and silicone rubber components, and a crosslinking agent containing hydrosilyl groups (SiH groups) , And composed of hardening catalyst used as needed.

The silicone resin component is an organopolysiloxane with a network structure obtained by hydrolyzing organochlorosilane or organoalkoxysilane and then undergoing a dehydration condensation reaction.

The silicone rubber component is two organopolysiloxanes with a linear structure.

As organic groups, silicone resin components and silicone rubber components are methyl, ethyl, propyl, butyl, phenyl, etc. Part of the aforementioned organic group is substituted with vinyl, hexenyl, allyl, butenyl, pentenyl, octenyl, (meth)acryloyl, (meth)acryloylmethyl, The unsaturated group of (meth)acryloyl propyl and cyclohexenyl. It is preferably an organic group having a vinyl group that is easily industrially available. In the addition reaction type polysiloxane adhesive composition, the crosslinking proceeds by the addition reaction of the unsaturated group and the hydrosilyl group to form a network structure and exhibit adhesiveness.

For example, the number of unsaturated groups of the vinyl group is generally 0.05 or more and 3.0 or less, preferably 0.1 or more and 2.5 or less, relative to 100 organic groups. By making the number of unsaturated groups with respect to 100 organic groups 0.05 or more, the reactivity with the hydrosilyl group can be prevented from decreasing and hardening is difficult, and a moderate adhesive force can be imparted. By making the number of unsaturated groups less than 3.0 relative to 100 organic groups, the cross-linking density of the adhesive is prevented from increasing, and the adhesive force and cohesive force increase, which will adversely affect the surface to be adhered.

As the aforementioned organopolysiloxane, specifically, KS-3703 manufactured by Shin-Etsu Chemical Industry Co., Ltd. (relative to 100 methyl groups, the number of vinyl groups is 0.6), Toray. BY23-753 (the number of vinyl groups is 0.1 relative to 100 methyl groups) and BY24-162 (the number of vinyl groups is 1.4 relative to 100 methyl groups), etc. manufactured by Dow Corning. In addition, Toray can also be used. SD4560PSA, SD4570PSA, SD4580PSA, SD4584PSA, SD4585PSA, SD4587L, and SD4592PSA manufactured by Dow Corning.

As mentioned above, the organopolysiloxane of the silicone resin component is usually mixed with the silicone rubber component. For the silicone rubber component, KS-3800 manufactured by Shin-Etsu Chemical Co., Ltd. (relative to methyl For 100, the number of vinyl is 7.6), Toray. BY24-162 (compared to 100 methyl groups, the number of vinyl groups is 1.4), BY24-843 (without unsaturated groups) and SD-7292 (compared to 100 methyl groups) manufactured by Dow Corning The number of vinyl groups is 5.0) and so on.

Specific examples of the aforementioned addition reaction type polysiloxane are described in, for example, Japanese Patent Application Laid-Open No. 10-219229.

Relative to 1 vinyl-like unsaturated group in the silicone resin component and silicone rubber component, it is usually 0.5 or more and 10 or less hydrogen atoms bonded to silicon atoms, preferably The crosslinking agent is blended in one or more and 2.5 or less. By making it 0.5 or more, it prevents the reaction of the unsaturated group like a vinyl group and the hydrosilyl group from not progressing completely and hardening failure. By making it 10 or less, it prevents the crosslinking agent from remaining unreacted and adversely affecting the surface to be adhered.

The addition reaction type silicone adhesive composition is also preferably accompanied by the aforementioned addition reaction type silicone component (a main agent composed of a silicone resin component and a silicone rubber component) and crosslinking It also contains hardening catalyst.

The hardening catalyst is used to promote the hydrosilylation reaction between the unsaturated groups in the silicone resin component and the silicone rubber component and the Si-H group in the crosslinking agent.

The hardening catalyst can include platinum-based catalysts, namely chloroplatinic acid, alcohol solution of chloroplatinic acid, reactant of chloroplatinic acid and alcohol solution, reactant of chloroplatinic acid and olefin compound, chlorination The reactants of platinum acid and vinyl-containing silicone compounds, platinum-olefin complexes, platinum-vinyl-containing silicone complexes, and platinum-phosphorus complexes. Specific examples of the aforementioned hardening catalyst are described in, for example, Japanese Patent Application Publication No. 2006-28311 and Japanese Patent Application Publication No. 10-147758.

More specifically, as a commercially available product, Toray. SRX-212 manufactured by Dow Corning, PL-50T manufactured by Shin-Etsu Chemical Industries, etc.

The blending amount of the hardening catalyst, based on the platinum component, is usually 5 mass ppm or more and 2000 mass ppm or less, preferably 10 mass ppm relative to the total amount of the silicone resin component and the silicone rubber component Above and below 500 mass ppm. By being 5 ppm by mass or more, the curability is prevented from lowering and the crosslinking density is lowered, that is, the adhesive force and cohesive force (retention force) are lowered. By being below 2000 ppm by mass, cost increase can be prevented and the adhesive layer can be maintained It is stable, and prevents excessive use of hardening catalyst from causing adverse effects on the surface to be adhered.

In the addition reaction type silicone adhesive composition, by blending the aforementioned components, the adhesive force can be exhibited even at room temperature. However, from the viewpoint of the stability of the adhesive force, it is preferable to use the addition reaction type The silicone adhesive composition is coated on the base material 11 or the peeling sheet described later, and after bonding the base material 11 and the peeling sheet, heating or irradiating active energy rays promotes the crosslinking agent to carry out the polysilicone resin component and the polysilicone The silicone rubber component undergoes a cross-linking reaction.

The heating temperature when the crosslinking reaction is promoted by heating is usually 60°C or more and 140°C or less, preferably 80°C or more and 130°C or less. Heating above 60°C prevents insufficient cross-linking of silicone resin components and silicone rubber components and insufficient adhesion. Heating below 140°C prevents heat shrinkage wrinkles on the substrate sheet. Deterioration, or discoloration.

When irradiating active energy rays to promote the cross-linking reaction, in electromagnetic waves or charged particle beams, active energy rays with energy quantum, that is, active light such as ultraviolet rays or electron beams can be used. When the electron beam is irradiated for crosslinking, a photopolymerization initiator is not required, but when irradiated with active light such as ultraviolet rays for crosslinking, it is preferable that the photopolymerization initiator is present.

There is no particular limitation on the photopolymerization initiator when irradiated with ultraviolet rays, and any photopolymerization initiator can be appropriately selected and used from among conventional photopolymerization initiators commonly used for ultraviolet curable resins. The photopolymerization initiator includes, for example, benzoins, benzophenones, acetophenones, α-hydroxyketones, α -amino ketones, α -diketones, and α-diketone diketones. Alkyl acetals, anthraquinones, thioxanthones, other compounds, etc.

These photopolymerization initiators may be used alone or in combination of two or more kinds. In addition, the amount used is usually 0.01 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the total amount of the addition reaction type polysiloxane component and the crosslinking agent used as the main agent. It is selected in the range of 0.05 parts by mass or more and 20 parts by mass or less.

By heating or irradiating active energy rays for cross-linking, an adhesive sheet with stable adhesive force can be obtained.

The acceleration voltage of the electron beam when crosslinking is performed by irradiating an electron beam, which is one of the active energy rays, is generally 130 kV or more and 300 kV or less, preferably 150 kV or more and 250 kV or less. By irradiating with an acceleration voltage above 130kV, it can prevent insufficient cross-linking between the silicone resin component and the silicone rubber component, and the adhesion becomes insufficient. By irradiating with an acceleration voltage below 300kV, adhesion can be prevented Deterioration or discoloration of the agent layer and the substrate sheet. The preferable range of the beam current is 1 mA or more and 100 mA or less.

The radiation dose of the irradiated electron beam is preferably 1 Mrad or more and 70 Mrad or less, more preferably 2 Mrad or more and 20 Mrad or less. By irradiating with a radiation dose of 1 Mrad or more, it is possible to prevent deterioration or discoloration of the adhesive layer and substrate sheet, and to prevent insufficient cross-linking resulting in insufficient adhesion. By irradiating with a radiation dose below 70 Mrad, the cohesive force reduction caused by the deterioration or discoloration of the adhesive layer can be prevented, and the deterioration or shrinkage of the substrate sheet can be prevented.

The irradiation amount during ultraviolet irradiation is appropriately selected, and the light amount is 100 mJ/cm ² or more and 500 mJ/cm ² or less, and the illuminance is 10 mW/cm ² or more and 500 mW/cm ² or less.

In order to prevent oxygen from hindering the reaction, heating and irradiation of active energy rays are preferably performed in a nitrogen environment.

The thickness of the adhesive layer 12 is appropriately determined according to the purpose of the adhesive sheet 10. In this embodiment, the thickness of the adhesive layer 12 is preferably 5 μm or more and 60 μm or less, more preferably 10 μm or more and 50 μm or less. When the thickness of the adhesive layer 12 is too thin, the adhesive layer 12 cannot follow the unevenness of the circuit surface of the semiconductor chip, which may cause gaps. For example, interlayer insulating materials and sealing resins enter the gap, and the electrode pads for wiring connections on the circuit surface of the chip may be blocked. If the thickness of the adhesive layer 12 is 5 μm or more, the adhesive layer 12 will easily follow the unevenness of the circuit surface of the chip, and the generation of gaps can be prevented. In addition, when the thickness of the adhesive layer 12 is too thick, the semiconductor chip sinks into the adhesive layer, which may cause a step difference between the semiconductor chip portion and the resin portion sealing the semiconductor chip. If such a step difference occurs, there is a risk of wiring disconnection during rewiring. If the thickness of the adhesive layer 12 is 60 μm or less, a step difference is unlikely to occur.

In this embodiment, the adhesive composition may contain other components within a range that does not impair the effect of the present invention. Other components that may be contained in the adhesive composition include, for example, organic solvents, flame retardants, tackifiers, ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, preservatives, antifungal agents, plasticizers, Defoamer, coloring agent, filler, and wettability regulator, etc.

The addition reaction type polysiloxane adhesive composition may also contain non-reactive polyorganosiloxanes such as polydimethylsiloxane and polymethylphenylsiloxane as additives.

(Oligomer sealing layer)

The oligomer sealing layer 13 is a layer for preventing the penetration of low molecular weight components (oligomers) into the adhesive layer 12. When the adhesive sheet 10 is exposed to high temperature conditions, it can be considered that the oligomers contained in the substrate 11 are deposited on the surface of the substrate 11 by heating. When the oligomer sealing layer 13 is not provided, the adhesive will penetrate The layer 12 then passes through the adhesive layer 12 to reach the surface of the adhesive layer 12. The oligomer sealing layer 13 preferably prevents penetration of the oligomer into the adhesive layer 12 even under high temperature conditions of 180° C. or more and 200° C. or less.

The material of the oligomer sealing layer 13 is not particularly limited as long as it can prevent the oligomer from penetrating into the adhesive layer 12.

For example, the oligomer sealing layer 13 is preferably obtained by curing a composition for an oligomer sealing layer containing (A) an epoxy compound, (B) a polyester compound, and (C) a polyfunctional amine compound Harden the film. In order to promote the hardening reaction, the composition for an oligomer sealing layer may further contain (D) an acid catalyst.

. (A) Epoxy compound

(A) The epoxy compound is preferably a bisphenol A epoxy compound. As a bisphenol A epoxy compound, bisphenol A diglycidyl ether etc. are mentioned. The weight average molecular weight (Mw) of the bisphenol A epoxy compound is preferably 1×10 ⁴ or more and 5×10 ⁴ or less. If the weight average molecular weight (Mw) of the bisphenol A epoxy compound is 1×10 ⁴ or more, the crosslink density necessary for the film can be obtained, and the precipitation of oligomers can be easily prevented. If the weight average molecular weight (Mw) is 5×10 ⁴ or less, the film can be prevented from becoming too hard. The weight average molecular weight Mw is a standard polystyrene conversion value measured by the gel permeation chromatography (GPC) method.

. (B) Polyester compound

(B) The polyester compound is not particularly limited, and it can be appropriately selected and used from known polyester compounds. As a polyester compound, specifically, a resin obtained by the condensation reaction of a polyhydric alcohol and a polybasic acid, such as a condensate of a dibasic acid and a dihydric alcohol, or a compound modified by non-drying oil fatty acid, etc. Convertible polyester compound, and condensate of dibasic acid and alcohol with more than principal element, ie, convertible polyester compound, etc. In this embodiment, all of these polyester compounds can be used.

The polyol used as the raw material of the (B) polyester compound includes dihydric alcohols, trihydric alcohols, and quaternary or higher polyhydric alcohols.

Examples of diols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, and neopentyl glycol.

Examples of trihydric alcohols include glycerin, trimethylolethane, and trimethylolpropane.

Examples of polyhydric alcohols of four or more valences include diglycerol, triglycerol, pentaerythritol, dipentaerythritol, mannitol, and sorbitol.

A polyol may be used individually by 1 type, and may be used in combination of 2 or more types.

Examples of polybasic acids include aromatic polybasic acids, aliphatic saturated polybasic acids, aliphatic unsaturated polybasic acids, and polybasic acids formed by the Diels-Alder reaction.

Examples of the aromatic polybasic acid include phthalic anhydride, terephthalic acid, isophthalic acid, and trimellitic anhydride.

Examples of the aliphatic saturated polybasic acid include succinic acid, adipic acid, and sebacic acid.

Examples of the aliphatic unsaturated polybasic acid include maleic acid, maleic anhydride, fumaric acid, itaconic acid, and citraconic anhydride.

The polybasic acid formed by the Diels-Alder reaction includes, for example, cyclopentadiene-maleic anhydride adduct, terpene-maleic anhydride adduct, and rosin-maleic anhydride adduct.

A polybasic acid may be used individually by 1 type, and may be used in combination of 2 or more types.

The non-drying oil fatty acid of the modifier includes, for example, caprylic acid, lauric acid, palmitic acid, stearic acid, oleic acid, linoleic acid, hypolinoleic acid, oleostearic acid, ricinoleic acid, dehydrated ricinoleic acid , Or coconut oil, linseed oil, tung oil, castor oil, dehydrated castor oil, soybean oil, safflower oil, and other fatty acids. These modifiers may be used singly or in combination of two or more kinds. In addition, as the polyester compound, one type may be used alone, or two or more types may be used in combination.

(B) The polyester compound preferably has an active hydrogen group as the base point of the crosslinking reaction. Examples of the active hydrogen group include a hydroxyl group, a carboxyl group, and an amino group. The polyester compound particularly preferably has a hydroxyl group. The hydroxyl value of the polyester compound is preferably 5 mgKOH/g or more and 500 mgKOH/g or less, more preferably 10 mgKOH/g or more and 300 mgKOH/g or less.

(B) The number average molecular weight (Mn) of the polyester compound is preferably 500 or more and 10,000 or less, more preferably 1,000 or more and 5,000 or less. The aforementioned number average molecular weight is a standard polystyrene conversion value measured by gel permeation chromatography (GPC).

(B) The glass transition temperature Tg of the polyester compound is preferably 0°C or more and 50°C or less.

By using a polyester compound having a number average molecular weight (Mn) and a glass transition temperature Tg in the aforementioned range, it is possible to impart appropriate flexibility to the cured film forming the oligomer sealing layer 13. The glass transition temperature Tg is based on JIS K 7121, using an input compensating differential scanning calorimeter, and measuring the starting temperature of the outer glass transition in the temperature range of -80°C to 250°C to obtain the glass transition temperature Tg.

. (C) Multifunctional amine-based compound

(C) Multifunctional amine-based compounds, for example, melamine compounds, urea compounds, benzoguanamine compounds, and diamines can be used.

The melamine compound includes, for example, hexamethoxymethyl melamine, methylated melamine compound, and butylated melamine compound.

Urea compounds include, for example, methylated urea compounds and butylated urea compounds.

Examples of the benzoguanamine compound include methylated benzoguanamine compounds and butylated benzoguanamine compounds.

Examples of diamines include ethylenediamine, tetramethylenediamine, hexamethylenediamine, N,N'-diphenylethylenediamine, and p-xylenediamine.

From the viewpoint of curability, the (C) polyfunctional amino compound is preferably hexamethoxymethylmelamine.

. (D) Acid catalyst

Examples of the acid catalyst (D) include hydrochloric acid and p-toluenesulfonic acid.

. Hardened film

In this embodiment, the oligomer sealing layer 13 is preferably made of (A) 50% by mass or more and 80% by mass or less, (B) 5% by mass or more and 30% by mass or less, and (C) 10% by mass The composition for oligomer sealing layer containing (A) bisphenol A epoxy compound, (B) polyester compound, and (C) polyfunctional amine compound is hardened to a blending ratio of above and 40% by mass or less. The hardened film obtained. When the (D) acid catalyst is blended in the composition for the oligomer sealing layer, the content of the (D) component is preferably 1% by mass or more and 5% by mass or less.

According to the cured film obtained by curing the composition for the oligomer sealing layer with the blending ratio in the aforementioned range, the effect of preventing the penetration of the oligomer into the adhesive layer 12 by the oligomer sealing layer 13 can be improved.

. Film thickness of oligomer sealing layer

The thickness of the oligomer sealing layer 13 is preferably 50 nm or more and 500 nm or less, more preferably 80 nm or more and 300 nm or less. If the thickness of the oligomer sealing layer 13 is 50 nm or more, the penetration of the oligomer into the adhesive layer 12 can be effectively prevented. If the thickness of the oligomer sealing layer 13 is 500 nm or less, the adhesive sheet 10 is easily wound when the core material becomes a roll shape. The material of the core material can include, for example, paper, plastic, and metal.

The adhesive sheet 10 of this embodiment preferably exhibits the following adhesive force after heating. First, the adhesive sheet 10 is attached to the adherend (copper foil or polyimide film), heated at 100°C and 30 minutes, then heated at 180°C and 30 minutes, and further heated at 190°C and 1 After heating for hours, the adhesion of the adhesive layer 12 to the copper foil at room temperature and the adhesion of the adhesive layer 12 to the polyimide film at room temperature are preferably 0.7N/25mm or more and Below 2.0N/25mm. If the adhesive force after such heating is 0.7N/25mm or more, when the substrate or the adherend is deformed due to heating, the adhesive sheet 10 can be prevented from being peeled off from the adherend. Moreover, if the adhesive force after heating is 2.0N/25mm or less, the peeling force will not become too high, and the adhesive sheet 10 will be easily peeled from the adherend. Furthermore, in this specification, room temperature refers to a temperature above 22°C and below 24°C. In this manual, the adhesive force is the value measured by the 180° peeling method at a stretching speed of 300 mm/min and the width of the adhesive sheet 25 mm.

(Method of manufacturing adhesive sheet)

The manufacturing method of the adhesive sheet 10 is not particularly limited.

For example, the adhesive sheet 10 is manufactured through the following steps.

First, the composition for an oligomer sealing layer is coated on the first substrate surface 11a of the substrate 11 to form a coating film. Next, the coating film is heated and cured to form a cured coating film as the oligomer sealing layer 13. The conditions for heat curing are, for example, 120° C. or more and 170° C. or less, 5 seconds or more and within 5 minutes.

Next, the adhesive composition is coated on the oligomer sealing layer 13 to form a coating film. Next, the coating film is dried to form the adhesive layer 12.

When the oligomer sealing layer composition is applied to form the oligomer sealing layer 13, and when the adhesive composition is applied to form the adhesive layer 12, it is preferable to use the oligomer sealing layer composition and the adhesive The agent composition is diluted with an organic solvent to prepare a coating liquid for use.

The organic solvent used in the preparation of the coating solution is not particularly limited. Examples of the organic solvent include aromatic solvents, aliphatic solvents, ester solvents, ketone solvents, and alcohol solvents. Examples of the aromatic solvent include benzene, toluene, and xylene. Examples of the aliphatic solvent include n-hexane and n-heptane. Examples of the ester solvent include ethyl acetate and butyl acetate. Examples of the ketone solvent include methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and cyclopentanone. Examples of the alcohol solvent include isopropanol and methanol.

The coating method can include, for example, a spin coating method, a spray coating method, a bar coating method, a knife coating method, a roll knife coating method, a roll coating method, a knife coating method, a die coating method, and Gravure coating method, etc.

In order to prevent the organic solvent and low boiling point components from remaining in the oligomer sealing layer 13 and the adhesive layer 12, after the coating liquid is applied to the base material 11, it is preferable to heat and dry the coating film.

When a crosslinking agent is blended into the adhesive composition, in order to advance the crosslinking reaction and increase the cohesive force, it is also preferable to heat the coating film.

(Use of adhesive sheet)

The adhesive sheet 10 is used when sealing semiconductor components. The adhesive sheet 10 is preferably used when sealing a semiconductor device that is not mounted on a metal lead frame but is stuck on the adhesive sheet 10. Specifically, the adhesive sheet 10 is preferably used not when sealing a semiconductor element mounted on a metal lead frame, but when sealing a semiconductor element in a state stuck to the adhesive layer 12. Forms that do not use metal lead frames to package semiconductor components include Panel Scale Package (PSP) and Wafer Level Package (WLP).

The adhesive sheet 10 is preferably used in a process having the following steps: a step of attaching a frame member formed with a plurality of openings to the adhesive sheet 10, and attaching a semiconductor chip to the opening exposed in the frame member The step of adhesive layer 12, the step of covering the semiconductor wafer with a sealing resin, and the step of thermally curing the sealing resin.

(Method of manufacturing semiconductor device)

A method of manufacturing a semiconductor device using the adhesive sheet 10 of this embodiment will be described.

2A to 2E are schematic diagrams illustrating the manufacturing method of the semiconductor device of this embodiment.

The method of manufacturing a semiconductor device of this embodiment is implemented: a step of attaching a frame member 20 formed with a plurality of openings 21 to the adhesive sheet 10 (adhesive sheet attaching step), and attaching the semiconductor chip CP to the exposed The step of the adhesive layer 12 of the opening 21 of the frame member 20 (bonding step), the step of covering the semiconductor chip CP with the sealing resin 30 (sealing step), the step of thermally curing the sealing resin 30 (the thermal curing step), and A step of peeling off the adhesive sheet 10 after heat curing (peeling step). If necessary, after the thermal hardening step, a step of attaching the reinforcing member 40 to the sealing body 50 sealed with the sealing resin 30 (reinforcing member attaching step) may be implemented. The steps are explained below.

. Adhesive sheet pasting steps

2A is a schematic diagram illustrating the step of attaching the frame member 20 to the adhesive layer 12 of the adhesive sheet 10.

The frame member 20 of this embodiment is formed in a lattice shape and has a plurality of openings 21. The frame member 20 is preferably formed of a material having heat resistance. Examples of the material of the frame member 20 include metals such as copper and stainless steel, and heat-resistant resins such as polyimide resin and glass epoxy resin.

The opening 21 is a hole that penetrates the front and back of the frame member 20. The shape of the opening 21 is not particularly limited as long as it can accommodate the semiconductor chip CP in the frame. The depth of the hole of the opening 21 is not particularly limited as long as it can accommodate the semiconductor chip CP.

. Joining steps

FIG. 2B is a schematic diagram illustrating the step of attaching the semiconductor chip CP to the adhesive layer 12.

When the adhesive sheet 10 is attached to the frame member 20, the adhesive layer 12 is exposed in the respective opening 21 according to the shape of the opening 21. The semiconductor chip CP is pasted on the adhesive layer 12 of each opening 21. The semiconductor chip CP is stuck so that its circuit surface is covered with the adhesive layer 12.

The semiconductor wafer CP is manufactured by, for example, performing a back grinding step in which the back surface of the semiconductor wafer on which a circuit is formed is ground, and a dicing step in which the semiconductor wafer is singulated. In the dicing step, the semiconductor wafer is attached to the adhesive layer of the dicing sheet, and the semiconductor wafer is singulated using a cutting means such as a dicing saw to obtain a semiconductor chip CP (semiconductor element).

The cutting device is not particularly limited, and a known cutting device can be used. In addition, there are no particular restrictions on the cutting conditions. Furthermore, a laser cutting method or a stealth dicing method can also be used instead of the method of cutting with a dicing knife.

After the dicing step, an expanding step of extending the dicing sheet to expand the interval between the plurality of semiconductor wafers CP may also be implemented. By carrying out the expansion step, the semiconductor chip CP can be picked up using a conveying means such as a collet. In addition, by performing the expansion step, the adhesive force of the adhesive layer of the dicing sheet is reduced, making it easier to pick up the semiconductor chip CP.

When the energy-ray polymerizable compound is blended into the adhesive composition of the dicing sheet or the adhesive layer, the adhesive layer is irradiated with energy rays from the base material side of the dicing sheet to harden the energy-ray polymerizable compound. When the energy-ray polymerizable compound is hardened, the cohesive force of the adhesive layer is increased, and the adhesive force of the adhesive layer can be reduced. Examples of the energy ray include ultraviolet (UV) and electron beam (EB), and ultraviolet rays are preferred. The irradiation of energy rays can be performed at any stage after the semiconductor wafer is attached and before the semiconductor wafer is peeled (pick-up). For example, energy rays may be irradiated before or after cutting, or energy rays may be irradiated after the expansion step.

. Sealing step and thermal hardening step

FIG. 2C is a schematic diagram illustrating a step of sealing the semiconductor chip CP attached to the adhesive sheet 10 and the frame member 20.

The material of the sealing resin 30 is a thermosetting resin, for example, epoxy resin etc. are mentioned. The epoxy resin used as the sealing resin 30 may include, for example, a phenol resin, an elastomer, an inorganic filler, and a hardening accelerator.

The method of covering the semiconductor chip CP and the frame member 20 with the sealing resin 30 is not particularly limited.

In the present embodiment, a description will be given by taking a form in which a sheet-like sealing resin 30 is used as an example. The sheet-shaped sealing resin 30 is placed so as to cover the semiconductor wafer CP and the frame member 20, and the sealing resin 30 is heated and hardened to form the sealing resin layer 30A. In this way, the semiconductor wafer CP and the frame member 20 are embedded in the sealing resin layer 30A. When the sheet-like sealing resin 30 is used, it is preferable to seal the semiconductor chip CP and the frame member 20 by a vacuum lamination method. With this vacuum lamination method, it is possible to prevent a gap from being generated between the semiconductor chip CP and the frame member 20. The temperature condition range of heating by the vacuum lamination method is, for example, 80°C or more and 120°C or less.

In the sealing step, a laminate sheet obtained by supporting a sheet-like sealing resin 30 on a resin sheet such as polyethylene terephthalate can also be used. At this time, after the laminated sheet is placed so as to cover the semiconductor wafer CP and the frame member 20, the resin sheet may be peeled from the sealing resin 30, and the sealing resin 30 may be heat-cured. Examples of such a laminated sheet include ABF film (manufactured by Ajinomoto Fine-Techno Co., Ltd.).

The method of sealing the semiconductor chip CP and the frame member 20 may also be a transfer molding method. At this time, for example, inside the mold of the sealing device, the semiconductor chip CP attached to the adhesive sheet 10 and the frame member 20 are accommodated. A fluid resin material is injected into the mold to harden the resin material. In the transfer molding method, the heating and pressure conditions are not particularly limited. An example of the general conditions of the transfer molding method is to maintain a temperature of 150°C or higher and a pressure of 4 MPa or higher and 15 MPa or lower for 30 seconds or more and 300 seconds or less. After that, the pressure is released, and the cured product is taken out from the sealing device, and placed in an oven to maintain a temperature of 150°C or higher for 2 hours or more and 15 hours or less. In this way, the semiconductor wafer CP and the frame member 20 are sealed.

When the sheet-shaped sealing resin 30 is used in the aforementioned sealing step, the first heating and pressing step may be performed before the step of thermally curing the sealing resin 30 (thermal curing step). In the first heating and pressing step, the semiconductor chip CP covered with the sealing resin 30 and the adhesive sheet 10 of the frame-attached member 20 are sandwiched from both sides with plate-shaped members, and pressed under specific temperature, time, and pressure conditions. By performing the first heating and pressing step, it is also easy to fill the sealing resin 30 in the gap between the semiconductor chip CP and the frame member 20. In addition, by performing the heating and pressing step, the unevenness of the sealing resin layer 30A made of the sealing resin 30 can also be flattened.

After the thermal curing step, when the adhesive sheet 10 is peeled off, the semiconductor chip CP and the frame member 20 sealed with the sealing resin 30 can be obtained. Hereinafter, there are those referred to as the sealing body 50.

. Reinforcing member pasting steps

FIG. 2D is a schematic diagram illustrating the step of attaching the reinforcing member 40 to the sealing body 50.

After peeling off the adhesive sheet 10, a rewiring step of forming a rewiring layer on the circuit surface of the exposed semiconductor chip CP and a bump fixing step are performed. In order to improve the operability of the sealing body 50 in the rewiring step and the bump fixing step, the step of attaching the sealing body 50 to the reinforcing member 40 (reinforcing member attaching step) may be implemented as needed. When the step of attaching the reinforcing member is performed, it is preferably performed before peeling off the adhesive sheet 10. As shown in FIG. 2D, the sealing body 50 is supported in a state sandwiched between the adhesive sheet 10 and the reinforcing member 40.

In this embodiment, the reinforcing member 40 includes a heat-resistant reinforcing plate 41 and a heat-resistant adhesive layer 42. Examples of the reinforcing plate 41 include a plate-shaped member containing a heat-resistant resin such as glass epoxy resin. The layer 42 is connected to the reinforcing plate 41 and the sealing body 50. The adhesive layer 42 is appropriately selected according to the materials of the reinforcing plate 41 and the sealing resin layer 30A.

In the step of attaching the reinforcing member, the adhesive layer 42 is preferably sandwiched between the sealing resin layer 30A of the sealing body 50 and the reinforcing plate 41, and further sandwiched by plate-shaped members from the side of the reinforcing plate 41 and the adhesive sheet 10 respectively , The second heating and pressing step of pressing under specific temperature, time, and pressure conditions. Through the second heating and pressing step, the sealing body 50 and the reinforcing member 40 are temporarily fixed. After the second heating and pressing step, in order to harden the adhesive layer 42, it is preferable to heat the temporarily fixed sealing body 50 and the reinforcing member 40 under specific temperature and time conditions. The heating and curing conditions are appropriately set according to the material of the adhesive layer 42, such as the conditions of 185°C, 80 minutes, and 2.4 MPa. In the second heating and pressing step, for example, a metal plate such as stainless steel can also be used as the plate-shaped member.

. Peeling step

FIG. 2E is a schematic diagram illustrating the step of peeling off the adhesive sheet 10.

In this embodiment, when the base material 11 of the adhesive sheet 10 is flexible, the frame member 20, the semiconductor chip CP, and the sealing resin layer 30A can be easily peeled off while the adhesive sheet 10 is bent. The peeling angle θ is not particularly limited, and it is preferable to peel the adhesive sheet 10 at a peeling angle θ of 90 degrees or more. If the peeling angle θ is 90 degrees or more, the adhesive sheet 10 can be easily peeled from the frame member 20, the semiconductor wafer CP, and the sealing resin layer 30A. The peeling angle θ is preferably 90 degrees or more and 180 degrees or less, more preferably 135 degrees or more and 180 degrees or less. By peeling off while bending the adhesive sheet 10 in this way, the load on the frame member 20, the semiconductor chip CP, and the sealing resin layer 30A can be reduced while peeling off, and the semiconductor caused by peeling of the adhesive sheet 10 can be suppressed. Damage to the chip CP and the sealing resin layer 30A. After peeling off the adhesive sheet 10, the aforementioned rewiring step, bump fixing step, etc. are performed. After the adhesive sheet 10 is peeled off, and before the rewiring step and the bump fixing step, etc., the aforementioned reinforcing member attaching step can also be implemented as needed.

When the reinforcing member 40 is attached, after the rewiring step and the bump fixing step, etc., the reinforcing member 40 is peeled from the sealing body 50 at a stage where it is not necessary to be supported by the reinforcing member 40.

After that, the sealed body 50 is singulated in units of semiconductor wafer CP (singulation step). The method of singulating the sealing body 50 into pieces is not particularly limited. For example, it can be singulated by the same method as that used when cutting the aforementioned semiconductor wafer. The step of singulating the sealing body 50 into pieces can be carried out in a state where the sealing body 50 is attached to a dicing sheet or the like. By singulating the sealing body 50 into pieces, a semiconductor package of a semiconductor chip CP unit is manufactured, and the semiconductor package is mounted on a printed wiring board or the like in the mounting step.

According to this embodiment, it is possible to provide the adhesive sheet 10 that can prevent contamination of the surface of the adherend even after the step of applying high temperature conditions.

The adherend that the adhesive layer 12 contacts is, for example, the semiconductor chip CP and the frame member 20. The semiconductor chip CP and the frame member 20 are exposed to high temperature conditions in a state in which they are in contact with the adhesive layer 12. Since the adhesive sheet 10 contains an oligomer sealing layer 13 between the substrate 11 and the adhesive layer 12, even if the adhesive sheet 10 is exposed to high temperature conditions, it will prevent the oligomer in the substrate 11 from contacting the adhesive layer 12 Infiltration. Therefore, according to the adhesive sheet 10, the surface contamination of the semiconductor chip CP and the frame member 20 can be prevented.

[Second Embodiment]

The second embodiment is different from the first embodiment in that oligomer sealing layers are provided on both sides of the substrate of the adhesive sheet. The second embodiment is the same as the first embodiment in other points, so the description will be omitted or simplified.

Fig. 3 shows a schematic cross-sectional view of the adhesive sheet 10A of the second embodiment.

The adhesive sheet 10A has a base material 11, an adhesive layer 12, an oligomer sealing layer 13 (first oligomer sealing layer), and an oligomer sealing layer 14 (second oligomer sealing layer).

The adhesive sheet 10A has oligomer sealing layers 13 and 14 on both surfaces of the substrate 11 (the first substrate surface 11a and the second substrate surface 11b), respectively. In the adhesive sheet 10A, an oligomer sealing layer 13 is laminated on the first substrate surface 11a, and an oligomer sealing layer 14 is laminated on the second substrate surface 11b. Preferably, the first substrate surface 11a is covered by the oligomer sealing layer 13 and the second substrate surface 11b is covered by the oligomer sealing layer 14. As in the first embodiment, an oligomer sealing layer 13 is provided between the base material 11 and the adhesive layer 12. The shape of the adhesive sheet 10A can also take any shape such as a sheet, a tape, or a label.

The oligomer sealing layer 13 (first oligomer sealing layer) is the same as the first embodiment.

The oligomer sealing layer 14 (second oligomer sealing layer) is a layer that is heated to prevent the oligomers deposited on the second substrate surface 11b of the substrate 11 from attaching to other components and causing contamination. The oligomer sealing layer 14 is preferably formed of the same material as the oligomer sealing layer 13.

The thickness of the oligomer sealing layer 14 is not particularly limited, but it is preferably a thickness in the same range as the oligomer sealing layer 13 described in the first embodiment. The more the thickness of the oligomer sealing layer increases, the better the oligomer sealing effect is. However, from the viewpoint of the productivity and cost of the adhesive sheet, the thickness of the oligomer sealing layer 13 and the oligomer sealing layer 14 are It may be 100 nm or more and 200 nm or less, or about 150 nm.

The manufacturing method of the adhesive sheet 10A is also not particularly limited.

For example, the adhesive sheet 10A is manufactured through the following steps. First, the composition for an oligomer sealing layer is coated on the first substrate surface 11a of the substrate 11 to form a coating film. Next, the coating film is heated and hardened to form the oligomer sealing layer 13. Next, the oligomer sealing layer composition is applied on the second substrate surface 11b of the substrate 11 to form a coating film. Next, the coating film is heated and hardened to form the oligomer sealing layer 14. Next, the adhesive composition is coated on the oligomer sealing layer 13 to form a coating film. Next, the coating film is dried to form the adhesive layer 12.

The adhesive sheet 10A can also be used in the same method of use as the adhesive sheet 10 of the first embodiment, and can be used in the manufacturing method of a semiconductor device in the same way as the adhesive sheet 10.

According to the adhesive sheet 10A, as with the adhesive sheet 10, even after the step of applying high temperature conditions, the surface of the adherend can be prevented from being contaminated.

Furthermore, according to the adhesive sheet 10A, the oligomer sealing layer 14 is also formed on the second substrate surface 11b, so that the oligomers deposited on the second substrate surface 11b can be prevented from attaching to members and devices other than the adherend. create pollution. For example, in the method of manufacturing a semiconductor device, it is possible to prevent contamination of the plate-shaped member in contact with the adhesive sheet 10A in the heating and pressing step.

[Changes in implementation form]

The present invention is not limited to the foregoing embodiments, and changes and improvements within the scope of achieving the purpose of the present invention are included in the present invention. In addition, in the following description, if the members and the like described in the foregoing embodiment are the same, the same reference numerals are assigned to omit or simplify the description.

In addition, the adhesive sheet may be a single sheet, or it may be provided in a state where a plurality of adhesive sheets are laminated. At this time, for example, the adhesive layer may also be covered by the base material of another adhesive sheet to be laminated.

In addition, the adhesive sheet can be a long-shaped sheet or can be provided in a roll-like state. The adhesive sheet wound in the shape of a roller can be wound out by the roller and cut to a desired size for use.

The adhesive layer of the adhesive sheet can also be covered by the peeling sheet. The peeling sheet is not particularly limited. For example, from the viewpoint of ease of handling, the release sheet preferably includes a release substrate and a release agent layer formed by coating a release agent on the release substrate. In addition, the release sheet may have a release agent layer only on one side of the release substrate, or may have a release agent layer on both sides of the release substrate. The peeling substrate includes, for example, a paper substrate, a laminated paper in which a thermoplastic resin such as polyethylene is laminated on the paper substrate, and a plastic film. Examples of the paper substrate include cellophane, coated paper, and cellophane paper. Plastic films include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; and polyolefin films such as polypropylene and polyethylene. The release agent can include, for example, olefin resins, rubber elastomers (such as butadiene resins, isoprene resins, etc.), long-chain alkyl resins, alkyd resins, fluorine resins, and silicone Department resin.

The thickness of the release sheet is not particularly limited. The thickness of the release sheet is usually 20 μm or more and 200 μm or less, preferably 25 μm or more and 150 μm or less.

The thickness of the release agent layer is not particularly limited. When a release agent-containing solution is applied to form a release agent layer, the thickness of the release agent layer is preferably 0.01 μm or more and 2.0 μm or less, more preferably 0.03 μm or more and 1.0 μm or less.

When a plastic film is used as the release substrate, the thickness of the plastic film is preferably 3 m or more and 50 m or less, more preferably 5 m or more and 40 m or less.

The adhesive sheet with the release sheet, for example, is manufactured through the following steps. First, the adhesive composition is applied on the release sheet to form a coating film. Next, the coating film is dried to form the adhesive layer 12. In addition, as described in the foregoing embodiment, the oligomer sealing layer 13 is formed in advance on the first substrate surface 11 a of the substrate 11. The adhesive layer 12 on the release sheet and the oligomer sealing layer 13 on the substrate 11 are bonded together. In the case of having the oligomer sealing layer 14, after forming the oligomer sealing layers 13 and 14 on both sides of the substrate 11, the adhesive layer 12 and the oligomer sealing layer 13 are bonded together.

In the foregoing embodiment, as the material of the sealing resin 30, the case of a thermosetting resin has been described as an example, but the present invention is not limited to this aspect. For example, the sealing resin 30 may be an energy-ray curable resin that is cured by energy rays such as ultraviolet rays.

In the foregoing embodiment, in the description of the manufacturing method of the semiconductor device, the aspect in which the frame member 20 is attached to the adhesive sheet 10 is taken as an example, but the present invention is not limited to this aspect. The adhesive sheet 10 can also be used in a manufacturing method of a semiconductor device that seals a semiconductor element without using a frame member.

[Example]

Hereinafter, examples are listed to further illustrate the present invention in detail. The present invention is not limited in any way by these embodiments.

[assessment method]

The evaluation of the adhesive sheet is carried out in accordance with the method shown below.

[Confirmation of Residues]

A semiconductor chip is attached to the adhesive layer of the adhesive sheet to obtain an adhesive sheet with the semiconductor chip attached.

The adhesive sheet with the semiconductor chip attached was heated at 190°C for 1 hour. After heating, peel off the adhesive sheet. Observe the adhered surface of the semiconductor wafer after peeling with a digital microscope (manufactured by KEYENCE, DIGITAL MICROSCOPE; VHX-1000) to confirm the presence or absence of residues. The observation magnification is set to 500 times. If the residue is not confirmed, it is judged as "A", and if the residue is confirmed, it is judged as "B".

Furthermore, the confirmation of whether the residue is an oligomer derived from the substrate is performed by the method shown below. Raman spectroscopy was used to measure the spectrum of the residue, and the spectrum was consistent with the characteristics of the substrate of the adhesive sheet to confirm that the residue was an oligomer derived from the substrate.

[Making of Adhesive Sheet] (Example 1) (1) Preparation of oligomer sealant liquid for coating

Blend the following (A) bisphenol A epoxy compound, (B) polyester compound, (C) polyfunctional amine compound and (D) acid catalyst, stir well, and prepare the coating oligomer of Example 1 Polymer sealant liquid (composition for oligomer sealant layer).

(A) Bisphenol A type epoxy compound

"EPICLON H-360" (trade name) manufactured by DIC Corporation, solid content concentration: 40% by mass, weight average molecular weight: 25,000

(B) Polyester compound

"Vylon GK680" (trade name) manufactured by Toyobo Co., Ltd., number average molecular weight: 6000, glass transition temperature: 10°C

(C) Multifunctional amine-based compound

Hexamethoxymethyl melamine, "Cymel 303" (trade name) manufactured by Cytec Industries, Japan

(D) Acid catalyst

Methanol solution of p-toluenesulfonic acid (solid content concentration 50% by mass)

Specifically, to 100 parts by mass of the above (A) bisphenol A epoxy compound, 14.29 parts by mass of the toluene diluted solution (solid content concentration: 30%) of the above (B) polyester compound and the above (C) hexamethyl 11.4 parts by mass of oxymethyl melamine were further diluted with a mixed solvent of toluene/methyl ethyl ketone=50% by mass/50% by mass until the solid content became 3% by mass, and stirred. Add 2.9 parts by mass (relative to 100 parts by mass of (A) bisphenol A epoxy compound) of (D) p-toluenesulfonic acid methanol solution (solid content concentration 50% by mass) to the stirred solution to obtain a coating Oligomer sealant liquid for cloth.

(2) Production of oligomer sealing layer

The prepared oligomer sealant solution for coating was stretched on a biaxially stretched polyethylene terephthalate film ("Diafoil T-100" (trade name) manufactured by Mitsubishi Plastics Co., Ltd., with a thickness of 50μm and a temperature of 100°C. The storage modulus of 3.2×10 ⁹ Pa) is uniformly coated by the Meyer bar coating method so that the thickness after drying becomes 150 nm. The coated film is passed through the oven, and the coating film is heated and hardened to obtain an oligomer sealing layer. The hot air blowing conditions in the oven are at a temperature of 150°C and a wind speed of 8m/min. The processing speed in the oven is adjusted so that the coated film will pass through the inside of the oven in 20 seconds.

(3) Production of adhesive composition

Blend the following materials (polymer, adhesion promoter, crosslinking agent, and diluent solvent), and stir well to prepare the adhesive liquid (adhesive composition) for coating of Example 1.

. Polymer: Acrylate copolymer, 40 parts by mass (solid content)

The acrylate copolymer was prepared by copolymerizing 92.8% by mass of 2-ethylhexyl acrylate, 7.0% by mass of 2-hydroxyethyl acrylate, and 0.2% by mass of acrylic acid.

. Adhesive aid: Hydrogenated polybutadiene with both terminal hydroxyl groups [manufactured by Nippon Soda Co., Ltd.; GI-1000], 5 parts by mass (solid content)

. Crosslinking agent: aliphatic isocyanate with hexamethylene diisocyanate (hexamethylene diisocyanate trimer isocyanate type modifier) [manufactured by Polyurethane Industry Co., Ltd. in Japan; Coronaate HX], 3.5 parts by mass (solid content)

. Dilution solvent: Using methyl ethyl ketone, the solid content concentration of the coating adhesive liquid is formulated to be 30% by mass.

(4) Making the adhesive layer

Apply the prepared adhesive liquid for coating to 38μm where the polysilicone release layer is provided using a chipped wheel coater (Comma coater, registered trademark), so that the film thickness after drying becomes 50μm The peeling layer side of the transparent polyethylene terephthalate film [made by LINTEC (Stock); SP-PET382150] is heated at 90°C and 90 seconds, followed by heating at 115°C and 90 seconds to coat The membrane is dry.

(5) Production of adhesive sheet

The adhesive layer produced on the surface of the release film and the oligomer sealing layer produced on the surface of the substrate were bonded together to obtain the adhesive sheet of Example 1.

(Example 2)

The adhesive sheet of Example 2 was produced in the same manner as Example 1, except that the polymer contained in the adhesive layer was different from that of Example 1.

The polymer used in Example 2 was made up of 80.8% by mass of 2-ethylhexyl acrylate, 7% by mass of 2-hydroxyethyl acrylate, 12% by mass of 4-propenylmorpholine, and 0.2% by mass of acrylic acid. Prepared by polymerization.

(Comparative example 1)

The adhesive sheet of Comparative Example 1 was produced in the same manner as in Example 1, except that the adhesive agent contained in the adhesive layer was different from that of Example 1, the base material was different, and the oligomer sealing layer was not provided.

The adhesion promoter used in Comparative Example 1 was acetyl tributyl citrate [manufactured by Taoka Chemical Industry Co., Ltd.]. Furthermore, acetyl tributyl citrate does not have the aforementioned reactive group.

The substrate used in Comparative Example 1 was a polyethylene terephthalate film [manufactured by Mitsubishi Plastics Corporation; PET50T-100, thickness 50 μm, storage modulus at 100° C. 3.2×10 ⁹ Pa]. The adhesive layer produced on the surface of the release film was bonded to the substrate to obtain an adhesive sheet of Comparative Example 1.

(Comparative example 2)

The adhesive sheet of Comparative Example 2 was produced in the same manner as Comparative Example 1, except that the adhesive agent contained in the adhesive layer was different from Comparative Example 1.

The adhesion promoter used in Comparative Example 2 was hydrogenated polybutadiene with two-terminal hydroxyl groups [manufactured by Nippon Soda Co., Ltd.; GI-1000].

(Comparative example 3)

The adhesive sheet of Comparative Example 3, except that the adhesive contained in the adhesive layer is different from that of Example 1, the thickness of the adhesive layer is different, the base material is different, and it does not have an oligomer sealing layer. Example 1 was produced in the same way.

In Comparative Example 3, a silicone adhesive was used.

In Comparative Example 3, 18 parts by mass (solid content) of polysiloxane-based adhesive Ad1 (SD4580PSA), 40 parts by mass (solid content) of polysiloxane-based adhesive Ad2 (SD4587L), and catalyst Cat1 (NC- 25 CAT) 0.3 parts by mass (solid content), 0.65 parts by mass (solid content) of catalyst Cat2 (CAT-SRX-212), and 5 parts by mass (solid content) of primer (BY24-712), stir well and prepare Adhesive liquid for coating (adhesive composition). The materials used in the adhesive composition of Comparative Example 3 are all Toray. Dow Corning (shares) system.

The adhesive liquid for coating of Comparative Example 3 was applied and dried on the release layer side of the release film so that the thickness after drying became 30 μm to produce an adhesive layer. The drying conditions are 130°C and 2 minutes. The substrate used in Comparative Example 3 was a polyethylene terephthalate film [manufactured by Mitsubishi Plastics; Diafoil PET50 T-100, thickness 50 μm, storage modulus 3.2×10 ⁹ Pa at 100° C.]. The adhesive layer produced on the surface of the release film was bonded to the substrate to obtain an adhesive sheet of Comparative Example 3.

Table 1 shows the evaluation results of the adhesive sheets of Example 1, Example 2, and Comparative Examples 1 to 3.

The adhesive sheets of Comparative Examples 1 to 3 do not have an oligomer sealing layer between the adhesive layer and the substrate. Therefore, it can be considered that residues precipitated on the surface of the adherend (semiconductor wafer) when exposed to a high temperature of 190°C .

On the other hand, the adhesive sheets of Example 1 and Example 2 have an oligomer sealing layer between the adhesive layer and the substrate. Therefore, even if exposed to a high temperature of 190°C, the adhesive sheet (semiconductor wafer) No residue will be deposited on the surface.

10‧‧‧Adhesive sheet

11‧‧‧Substrate

11a‧‧‧First substrate surface

11b‧‧‧Second substrate surface

12‧‧‧Adhesive layer

13‧‧‧Oligomer sealing layer

Claims (8)

An adhesive sheet, which is an adhesive sheet used to seal semiconductor elements on the adhesive sheet at a temperature above 180°C and below 200°C. It has a base material containing a polyester resin and an adhesive layer containing an adhesive. , And the oligomer sealing layer provided between the substrate and the adhesive layer, and the weight of the polyester resin is 50% by mass or more in the mass of the total material constituting the substrate. The adhesive sheet of claim 1, wherein the thickness of the aforementioned oligomer sealing layer is 50 nm or more and 500 nm or less. Such as the adhesive sheet of claim 1, wherein the thickness of the aforementioned oligomer sealing layer is 80 nm or more and 300 nm or less. Such as the adhesive sheet of claim 1, wherein the storage modulus of the aforementioned substrate at 100°C is 1×10 ⁷ Pa or more. The adhesive sheet of claim 1, wherein the adhesive layer contains an acrylic adhesive composition or a silicone adhesive composition. The adhesive sheet of claim 5, wherein the adhesive layer contains the acrylic adhesive composition, and the acrylic adhesive composition contains 2-ethylhexyl acrylate The ester is an acrylic copolymer of the main monomer. The adhesive sheet of claim 5, wherein the adhesive layer contains the silicone adhesive composition, and the silicone adhesive composition contains an addition polymerization type silicone resin. The adhesive sheet of claim 1, wherein the oligomer sealing layer is provided on both sides of the substrate.

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