JP2019070094A - Double-sided adhesive tape, and method of producing semiconductor device - Google Patents

Abstract

To provide a non-support type double-sided adhesive tape capable of protecting an adherend with a sufficient adhesive force, exerting high heat resistance, and adhesive deposit suppression performance, and capable of photocuring an adhesive even when using a light-impermeable support plate, and a method of producing a semiconductor device using the double-sided adhesive tape.SOLUTION: A non-support type double-sided adhesive tape includes: an ultraviolet ray-permeable non-ultraviolet ray curable adhesive layer; and an ultraviolet ray-curable adhesive layer laminated on the non-ultraviolet ray curable adhesive layer, where the ultraviolet ray-curable adhesive layer contains an ultraviolet ray-curable adhesive constituent, and a silicone compound, the non-ultraviolet ray curable adhesive layer contains (A) (a) 92-97 wt.% of a (meth)acrylic acid alkyl ester a carbon number of whose alkyl group is 4-12 and (b) 100 pts.wt. of a (meth)acrylic copolymer containing 3.0-8.0 wt.% of a carboxyl group-containing monomer as a constituent, and (B) 0.5-5 pts.wt. of an isocyanate crosslinking agent.SELECTED DRAWING: None

Description

The present invention can protect an adherend with sufficient adhesive power, exert high heat resistance and adhesive residue suppression performance, and photocure the adhesive even when using a support plate that does not transmit light. The present invention relates to a non-support type double-sided pressure-sensitive adhesive tape.

In the manufacturing process of a semiconductor chip, an adhesive tape is used in order to facilitate handling at the time of processing of a wafer or a semiconductor chip and to prevent damage. For example, when a thick film wafer cut out from a high purity silicon single crystal or the like is ground to a predetermined thickness to form a thin film wafer, grinding is performed after an adhesive tape is attached to the thick film wafer.

The adhesive composition used for such a pressure-sensitive adhesive tape has high adhesiveness which can firmly fix an adherend such as a wafer or a semiconductor chip during a processing step, and after completion of the step, the object such as a wafer or a semiconductor chip It is required to be able to peel off without damaging the adherend (hereinafter, also referred to as "high adhesion easy peeling").
Patent Document 1 discloses a pressure-sensitive adhesive tape using a photo-curable pressure-sensitive adhesive which is cured by irradiation with light such as ultraviolet light to reduce adhesion as an adhesive composition which achieves high adhesion and easy peeling. . By using a photo-curable pressure-sensitive adhesive as the pressure-sensitive adhesive, the semiconductor can be surely fixed during the processing step, and it can be easily peeled off by irradiating ultraviolet light or the like.

Unexamined-Japanese-Patent No. 5-32946

In recent years, due to thinning and miniaturization of semiconductor products, the substrate has been thinned to 100 μm or less (hereinafter, the thinned substrate is referred to as a thin substrate), and in order to prevent warpage and damage in manufacturing the substrate. Adhesive tape has come to be used. In the production of such a thin substrate, a substrate such as a polyimide film which is the base of the substrate is fixed to a support plate via a non-support type double-sided pressure-sensitive adhesive tape having no substrate, and then processing such as wiring is performed. It will be. However, the support plate used in the production of thin substrates is often an opaque material such as aluminum because of its cost, recyclability, and ease of handling, and such an opaque support plate is used for the conventional photocurable adhesive. There is a problem that the double-sided pressure-sensitive adhesive tape used can not be cured.

Further, since a high temperature treatment of applying heat of 150 ° C. or more is performed in the manufacturing process of a thin substrate, the double-sided pressure-sensitive adhesive tape used is required to have heat resistance and adhesion progression resistance not to promote adhesion even under high temperature. The adhesive tape used in the manufacturing process with the conventional high temperature processing is mix | blended with the silicone bleed agent, in order to suppress an adhesive bond. However, when the silicone bleed agent is compounded in the non-support type double-sided adhesive tape, the adhesion progress between the base and the double-sided adhesive tape can be suppressed, but the silicone bleed agent bleeds out at the interface between the double-sided adhesive tape and the support plate. There is also a problem that the adhesion between the support plate and the double-sided adhesive tape is reduced. In addition, since double-sided adhesive tapes used in the manufacture of electronic components such as thin substrates and semiconductor devices are often stored for a certain period before they are used, bleed out tends to progress during storage, and the problem is remarkable It had become.

The present invention can protect an adherend with sufficient adhesive power, exert high heat resistance and adhesive residue suppression performance, and photocure the adhesive even when using a support plate that does not transmit light. An object of the present invention is to provide a non-support type double-sided pressure-sensitive adhesive tape and a method of manufacturing a semiconductor device using the double-sided pressure-sensitive adhesive tape.

The present invention is a non-support type double-sided pressure-sensitive adhesive tape including a non-UV-curable non-UV-curable pressure-sensitive adhesive layer and a UV-curable pressure-sensitive adhesive layer laminated on the non-UV-curable pressure-sensitive adhesive layer. The ultraviolet-curable pressure-sensitive adhesive layer contains an ultraviolet-curable pressure-sensitive adhesive component and a silicone compound, and the non-ultraviolet-curable pressure-sensitive adhesive layer contains (A) (a) alkyl group having 4 to 12 carbon atoms (meth) acrylic 100 parts by weight of (meth) acrylic copolymer containing 92 to 97% by weight of acid alkyl ester and 3.0 to 8.0% by weight of (b) carboxyl group-containing monomer, and (B) isocyanate system A double-sided pressure-sensitive adhesive tape containing 0.5 to 5 parts by weight of a crosslinking agent.
The present invention will be described in detail below.

The double-sided pressure-sensitive adhesive tape of the present invention includes a non-UV-curable non-UV-curable pressure-sensitive adhesive layer and a UV-curable pressure-sensitive adhesive layer laminated on the non-UV-curable pressure-sensitive adhesive layer.
The double-sided pressure-sensitive adhesive tape includes an ultraviolet ray transmitting non-ultraviolet curable adhesive layer, whereby the ultraviolet ray curable adhesive layer is attached to an adherend, and after the ultraviolet curable adhesive layer is cured, the non ultraviolet curable adhesive Since the agent layer can be attached to the support plate, the ultraviolet-curable pressure-sensitive adhesive can be cured even if the support plate is opaque. Here, the term “ultraviolet light transmittance” means that the light absorption wavelength band of the ultraviolet polymerization initiator contained in the above-mentioned ultraviolet-curable pressure-sensitive adhesive layer overlaps with the wavelength band of the non-ultraviolet-curable pressure-sensitive adhesive layer transmitting light. In particular, it is preferable that the light absorption wavelength band of the UV polymerization initiator and the wavelength band of 0.2 or less of the absorbance of the non-UV-curable pressure-sensitive adhesive layer overlap.

The ultraviolet ray curable adhesive layer contains an ultraviolet ray curable adhesive component.
Examples of the above-mentioned UV-curable pressure-sensitive adhesive component include UV-curable pressure-sensitive adhesives containing a polymerizable polymer as a main component and containing a UV polymerization initiator as a polymerization initiator. For the polymerizable polymer, for example, a (meth) acrylic polymer having a functional group in the molecule (hereinafter referred to as a functional group-containing (meth) acrylic polymer) is synthesized in advance, and the above-mentioned functional group is reacted with the molecule. It can be obtained by reacting a compound having a functional group with a radical polymerizable unsaturated bond (hereinafter referred to as a functional group-containing unsaturated compound).

The functional group-containing (meth) acrylic polymer has, as a main monomer, an acrylic acid alkyl ester and / or a methacrylic acid alkyl ester in which the carbon number of the alkyl group is usually in the range of 2 to 18, and this and a functional group containing monomer Further, they may be obtained by copolymerizing these with other modifying monomers which can be copolymerized in a conventional manner, as required. The weight average molecular weight of the functional group-containing (meth) acrylic polymer is usually about 200,000 to 2,000,000. In the present specification, the weight average molecular weight can be generally determined by GPC method, and specifically, the method shown in the examples can be used.

As said functional group containing monomer, a carboxyl group containing monomer, a hydroxyl group containing monomer, an epoxy group containing monomer, an isocyanate group containing monomer, an amino group containing monomer etc. are mentioned, for example. Examples of the carboxy group-containing monomer include acrylic acid and methacrylic acid. Examples of the hydroxyl group-containing monomer include hydroxyethyl acrylate and hydroxyethyl methacrylate. Examples of the epoxy group-containing monomer include glycidyl acrylate and glycidyl methacrylate. Examples of the isocyanate group-containing monomer include isocyanate ethyl acrylate and isocyanate ethyl methacrylate. Examples of the amino group-containing monomer include aminoethyl acrylate and aminoethyl methacrylate.

Examples of the other copolymerizable modifying monomer include various monomers used for general (meth) acrylic polymers such as vinyl acetate, acrylonitrile and styrene.

As the functional group-containing unsaturated compound to be reacted with the functional group-containing (meth) acrylic polymer, the same functional group-containing monomer as described above according to the functional group of the functional group-containing (meth) acrylic polymer is used it can. For example, when the functional group of the functional group-containing (meth) acrylic polymer is a carboxyl group, an epoxy group-containing monomer or an isocyanate group-containing monomer is used. When the functional group is a hydroxyl group, an isocyanate group-containing monomer is used. When the functional group is an epoxy group, a carboxyl group-containing monomer or an amide group-containing monomer such as acrylamide is used. When the functional group is an amino group, an epoxy group-containing monomer is used.

Examples of the ultraviolet polymerization initiator include those activated by irradiation with ultraviolet light having a wavelength of 200 to 410 nm. As such an ultraviolet polymerization initiator, for example, acetophenone derivative compound, benzoin ether type compound, ketal derivative compound, phosphine oxide derivative compound, bis (η5-cyclopentadienyl) titanocene derivative compound, benzophenone, Photo radical polymerization initiators such as Michler's ketone, chlorothioxanthone, todecyl thioxanthone, dimethyl thioxanthone, diethyl thioxanthone, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethyl phenyl propane and the like can be mentioned. Examples of the acetophenone derivative compounds include methoxyacetophenone and the like. Examples of the benzoin ether compounds include benzoin propyl ether and benzoin isobutyl ether. Examples of the ketal derivative compound include benzyl dimethyl ketal, acetophenone diethyl ketal and the like. These ultraviolet polymerization initiators may be used alone or in combination of two or more.

The UV-curable pressure-sensitive adhesive layer preferably contains a radical polymerizable polyfunctional oligomer or monomer. When the ultraviolet ray curable adhesive layer contains a radical polymerizable polyfunctional oligomer or monomer, the ultraviolet ray curability is improved.
The above-mentioned polyfunctional oligomer or monomer preferably has a weight average molecular weight of 10,000 or less, more preferably the weight average molecular weight of the ultraviolet curable adhesive layer so that three-dimensional reticulation of the ultraviolet curable adhesive layer can be efficiently performed. The molecular weight is 5,000 or less and the number of radically polymerizable unsaturated bonds in the molecule is 2 to 20. The said weight average molecular weight can be determined, for example using a GPC measuring method, and can specifically use the method shown by the Example.

The polyfunctional oligomer or monomer is, for example, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxy pentaacrylate, dipentaerythritol hexaacrylate or the same methacrylate And the like. In addition, 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylate, methacrylates similar to the above, and the like can be mentioned. These polyfunctional oligomers or monomers may be used alone or in combination of two or more.

The ultraviolet curable pressure-sensitive adhesive layer contains a silicone compound.
When the silicone compound is contained, the silicone compound bleeds out to the interface between the ultraviolet-curable pressure-sensitive adhesive layer and the adherend, so that the double-sided pressure-sensitive adhesive tape can be easily peeled off after the treatment is completed. In addition, since the silicone compound is excellent in heat resistance, it is possible to suppress burning and the like of the ultraviolet-curable pressure-sensitive adhesive layer and suppress adhesive residue even when performing processing involving heating at 150 ° C. or higher.

The silicone compound preferably has a functional group crosslinkable with the ultraviolet curable pressure sensitive adhesive component.
Since the silicone compound has a functional group crosslinkable to the ultraviolet curable adhesive component and the silicone compound chemically reacts with the ultraviolet curable adhesive component upon irradiation with ultraviolet radiation and is incorporated into the ultraviolet curable adhesive component, Contamination due to adhesion of the silicone compound to the adherend is suppressed. The functionality of the silicone compound is, for example, 2 to 6, preferably 2 to 4 and more preferably 2. Although the said functional group is suitably determined by the functional group contained in an ultraviolet curable adhesive component, for example, the ultraviolet curable adhesive component is a photocuring which has a (meth) acrylic-acid alkylester type polymerizable polymer as a main component In the case of a pressure-sensitive adhesive, a functional group capable of crosslinking with a (meth) acrylic group is selected.
The functional group crosslinkable with the (meth) acrylic group is a functional group having an unsaturated double bond, and specifically includes, for example, a vinyl group, a (meth) acrylic group, an allyl group, a maleimide group, etc. Choose a silicone compound.

The silicone compound preferably has a weight average molecular weight of 300 to 50,000.
When the weight average molecular weight of the silicone compound is 300 or more, bleeding out to the non-UV-curable pressure-sensitive adhesive layer can be further suppressed depending on the size of the molecular size. By the weight average molecular weight being 50000 or less, it is possible to bleed out to the interface between the ultraviolet-curable pressure-sensitive adhesive layer and the adherend to further suppress the adhesion progression. The lower limit of the weight average molecular weight of the silicone compound is more preferably 400, still more preferably 500, still more preferably 10000, and still more preferably 5000. In the present invention, the weight average molecular weight of the silicone compound can be determined by GPC analysis, and specifically, the method shown in the examples can be used.

As a silicone compound which has the said functional group and a weight average molecular weight, a silicon diacrylate is mentioned, for example. When silicon diacrylate is used, the heat resistance and the releasability are further improved.

The preferable content of the silicone compound is 1 part by weight at the lower limit, 50 parts by weight at the upper limit, 10 parts by weight at the more preferable lower limit, and 40 parts by weight at the upper limit with respect to 100 parts by weight of the polymerizable polymer.

The ultraviolet-curable pressure-sensitive adhesive layer may contain a known additive such as an inorganic filler such as fumed silica, a plasticizer, a resin, a surfactant, a wax, and a particulate filler.

Although the thickness of the said ultraviolet curable adhesive layer is not specifically limited, It is preferable that a minimum is 5 micrometers and an upper limit is 100 micrometers. An adherend can be protected with sufficient adhesive force as the thickness of the said ultraviolet curable adhesive layer is the said range, and also the adhesive residue at the time of peeling can also be suppressed. The more preferable lower limit of the thickness of the ultraviolet-curable pressure-sensitive adhesive layer is 10 μm, and the more preferable upper limit is 60 μm.

The non-UV-curable pressure-sensitive adhesive layer contains a (meth) acrylic copolymer containing an alkyl group having a carbon number of 4 to 12 (meth) acrylic acid alkyl ester and a carboxyl group-containing monomer as a component. .
By using a (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group as a component, it is possible to obtain a non-UV-curable pressure-sensitive adhesive layer having sufficient adhesiveness and UV transparency. In addition, by using a carboxyl group-containing monomer as a component, the cohesion of the non-UV-curable pressure-sensitive adhesive layer can be enhanced to impart greater adhesion. Furthermore, since the carboxyl group, which is a polar group, inhibits the approach of the low polarity silicone compound, it is possible to suppress the bleeding of the silicone compound to the non-UV-curable pressure-sensitive adhesive layer side. The preferred lower limit of the carbon number of the alkyl group of the (meth) acrylic acid alkyl ester is 8, and the preferred upper limit is 10.

Examples of the (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group include butyl acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, and isononyl (meth) acrylate. Among them, butyl acrylate is preferable because of its excellent adhesion.

Examples of the carboxyl group-containing monomer include acrylic acid and methacrylic acid. Among them, acrylic acid is preferable because it can impart high adhesive strength.

The (meth) acrylic copolymer has 92 to 97% by weight of (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group, and 3.0 to 8.0% by weight of a carboxyl group-containing monomer %contains.
When the content of the (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group is in the above range, sufficient adhesive strength can be secured. When the content of the carboxyl group-containing monomer is 3.0% by weight or more, the bleed out of the silicone compound to the non-UV-curable pressure-sensitive adhesive layer can be further suppressed. When the content of the carboxyl group-containing monomer is 8.0% by weight or less, the acidity of the (meth) acrylic copolymer can be adjusted to an appropriate range, and bleeding of the silicone compound to the non-UV-curable pressure-sensitive adhesive layer Out can be suppressed more.
From the same viewpoint, the content of the (meth) acrylic acid alkyl ester in the (meth) acrylic copolymer is preferably 93% by weight, more preferably 94% by weight, and 96% by weight, from the same viewpoint. It is. From the same viewpoint, the content of the carboxyl group-containing monomer in the (meth) acrylic copolymer is preferably 4% by weight, 7% by weight, and 6% by weight from the same viewpoints. .

The non-UV-curable pressure-sensitive adhesive contains an isocyanate-based crosslinking agent.
The chemical resistance of the non-UV-curable pressure-sensitive adhesive layer can be improved by containing the crosslinking agent. Moreover, since an isocyanate type crosslinking agent reacts with a hydroxyl group and does not react with a carboxyl group, a large number of carboxyl groups exist in the (meth) acrylic copolymer even after the crosslinking reaction. As a result, since the polarity of the non-UV-curable pressure-sensitive adhesive layer is kept high, it is difficult for the low polarity silicone compound to bleed out to the non-UV-curable pressure-sensitive adhesive layer, and the adhesion of the non-UV-curable pressure-sensitive adhesive layer You can suppress the decline. In addition, since it will react with the carboxyl group of a (meth) acrylic-type copolymer when crosslinking agents other than an isocyanate type, for example, an epoxy-type crosslinking agent, are used, (meth) acrylic-type co-weight by a crosslinking reaction The combined carboxyl group is consumed. As a result, it is considered that the polarity of the non-UV-curable pressure-sensitive adhesive layer is lowered and the silicone compound is easily bled out to the non-UV-curable pressure-sensitive adhesive layer.
As said isocyanate type crosslinking agent, a cyclohexylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate etc. are mentioned, for example.

The content of the isocyanate-based crosslinking agent is 0.5 to 5 parts by weight with respect to 100 parts by weight of the (meth) acrylic copolymer.
When the content of the isocyanate crosslinking agent is in the above range, the (meth) acrylic copolymer can be sufficiently crosslinked. The lower limit of the content of the isocyanate-based crosslinking agent relative to 100 parts by weight of the (meth) acrylic copolymer is 0.6 parts by weight, the lower limit is more preferably 0.7 parts by weight, and the upper limit is preferably 4 parts by weight. The upper limit is 3 parts by weight.

The non-UV-curable pressure-sensitive adhesive layer may contain known additives such as an inorganic filler such as fumed silica, a plasticizer, a resin, a surfactant, a wax, and a fine particle filler.

In the non-UV-curable pressure-sensitive adhesive layer, the ratio ([-NCO / -OH] ratio) of the hydroxyl group in the (meth) acrylic copolymer to the isocyanate group in the isocyanate-based crosslinking agent is 0.3 to It is preferably 3.0.
When the ratio of the isocyanate group to the hydroxyl group is in the above range, the (meth) acrylic copolymer can be sufficiently crosslinked, and the chemical resistance of the double-sided pressure-sensitive adhesive tape can be further improved. The more preferable lower limit of the ratio of the hydroxyl group in the (meth) acrylic copolymer to the isocyanate group in the above-mentioned isocyanate crosslinking agent is 0.4, the more preferable upper limit is 2.8, and the still more preferable upper limit is 2.5 .

The thickness of the non-UV-curable pressure-sensitive adhesive layer is not particularly limited, but the lower limit is preferably 5 μm and the upper limit is 100 μm. When the thickness of the non-UV-curable pressure-sensitive adhesive layer is in the above range, it can be adhered to the support plate with sufficient adhesive force, and the adherend can be fixed securely. The more preferable lower limit of the thickness of the non-UV-curable pressure-sensitive adhesive layer is 10 μm, and the more preferable upper limit is 60 μm.

The double-sided pressure-sensitive adhesive tape of the present invention is a non-support type double-sided pressure-sensitive adhesive tape having no substrate. In the case of the support type having a substrate, the silicone compound does not bleed out to the interface on the support plate side, but the cost is lower than that of the non-support type.

In the double-sided pressure-sensitive adhesive tape of the present invention, a UV-transparent release film is laminated on the surface of the non-UV-curable pressure-sensitive adhesive layer opposite to the surface on which the UV-curable pressure-sensitive adhesive layer is laminated. preferable.
By having the release film on the non-UV-curable pressure-sensitive adhesive layer, the non-UV-curable pressure-sensitive adhesive layer can be protected until it is attached to the support plate, and the handleability of the double-sided pressure-sensitive adhesive tape can be improved. Moreover, the curing process described later can be performed while the non-UV-curable pressure-sensitive adhesive layer is protected because the release film is UV-transparent.

The release film of the above-mentioned ultraviolet ray transmission is not particularly limited as long as it is ultraviolet ray transmission, and for example, polyethylene naphthalate (PEN), polyimide (PI), polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polyethylene Examples thereof include terephthalate (PET), polybutylene terephthalate (PBT), polyhexamethylene terephthalate, polybutylene naphthalate, butanediol terephthalic acid polytetramethylene glycol copolymer, and butanediol terephthalic acid polycaprolactone copolymerization. Among them, polyethylene terephthalate (PET) is preferable.

In the double-sided pressure-sensitive adhesive tape of the present invention, the ultraviolet-curable pressure-sensitive adhesive layer and the non-UV-curable pressure-sensitive adhesive layer are located in the outermost layer (layer in contact with the adherend). You may have another layer between the type | mold adhesive layer.

In the double-sided pressure-sensitive adhesive tape of the present invention, the gel fraction of the non-UV-curable pressure-sensitive adhesive layer is 60% or more, and the gel fraction of the UV-curable pressure-sensitive adhesive layer is 80% or more after UV curing preferable.
The chemical resistance of the double-sided pressure-sensitive adhesive tape can be improved by the gel fraction of the non-UV-curable pressure-sensitive adhesive layer and the UV-curable pressure-sensitive adhesive layer being not less than the above lower limit value. The lower limit of the gel fraction of the non-UV-curable pressure-sensitive adhesive layer is more preferably 85%, still more preferably 90%, particularly preferably 95%. The upper limit of the gel fraction of the non-UV-curable pressure-sensitive adhesive layer is not particularly limited, but is preferably 99%. The more preferable lower limit of the gel fraction of the ultraviolet-curable pressure-sensitive adhesive layer is 85%, and the more preferable lower limit is 90%. Although the upper limit of the gel fraction of the said ultraviolet curable adhesive layer is not specifically limited, It is preferable that it is 99%. In addition, the gel fraction of a ultraviolet curable adhesive layer points out the gel fraction before hardening. When the double-sided pressure-sensitive adhesive tape has a layer other than the UV-curable pressure-sensitive adhesive layer and the non-UV-curable pressure-sensitive adhesive layer, the layer preferably also satisfies the gel fraction.

The method for producing the double-sided pressure-sensitive adhesive tape of the present invention is not particularly limited, and a conventionally known method can be used. For example, a solution of the above-mentioned UV curable adhesive component is coated on a film subjected to release treatment and dried to form an UV curable adhesive layer, and the same is applied on a film subjected to another release treatment. After forming a non-ultraviolet-curable pressure-sensitive adhesive layer by a method, it can be manufactured by bonding an ultraviolet-curable pressure-sensitive adhesive layer and a non-ultraviolet-curable pressure-sensitive adhesive layer.

Although the application of the double-sided pressure-sensitive adhesive tape of the present invention is not particularly limited, it can be particularly suitably used as a protective tape in the production of a semiconductor device using an opaque support plate and having a production process involving high temperature treatment.

A substrate sticking step of sticking the double-sided pressure-sensitive adhesive tape of the present invention from a UV-curable pressure-sensitive adhesive layer to a substrate, a curing step of curing the UV-curable pressure-sensitive adhesive layer by irradiating ultraviolet rays, a non-UV-curable pressure-sensitive adhesive layer A method of manufacturing a semiconductor device also includes a support plate attaching step of attaching a support plate thereon, a heat treatment step of treating the substrate at a high temperature of 150 ° C. or more, and a peeling step of peeling the substrate from the double-sided adhesive tape. , Is one of the present invention.

In the method of manufacturing a semiconductor device of the present invention, first, a double-sided pressure-sensitive adhesive tape having an ultraviolet-curable pressure-sensitive adhesive layer and an ultraviolet-ray transmitting non-ultraviolet-curable pressure-sensitive adhesive layer is used as a substrate from the ultraviolet-curable pressure-sensitive adhesive layer side. Perform the board sticking process to stick to
The above-mentioned substrate includes not only the substrate on which the semiconductor chip is mounted, but also the base material etc. which becomes the base in the production of the substrate. Examples of the substrate include polyimide films and glass epoxy substrates.

Next, in the method of manufacturing a semiconductor device according to the present invention, a curing step of curing the UV curable pressure-sensitive adhesive layer by irradiating ultraviolet rays is performed.
By curing the ultraviolet-curable pressure-sensitive adhesive layer, the double-sided pressure-sensitive adhesive tape can be easily peeled from the substrate after completion of the treatment while suppressing adhesive residue. In the conventional method, light curing is performed after the double-sided pressure-sensitive adhesive tape is attached to the substrate and the support plate, and therefore light curing can not be performed when the support plate is a material that does not transmit light. However, in the method for manufacturing a semiconductor device according to the present invention, since the UV curable adhesive layer is cured before the double-sided adhesive tape is attached to the support plate, the photocurable adhesion is a material even if the support plate does not transmit light. The agent can be cured. In addition, since the non-UV curable adhesive layer of the double-sided tape is UV-transparent, even if the UV curable adhesive layer is irradiated with UV light from the non-UV curable adhesive layer side, the UV curable adhesive is sufficient. Can be cured. In addition, since the ultraviolet curable adhesive layer is cured after being attached to the substrate, even if the ultraviolet curable adhesive layer is cured before processing the substrate, the double-sided adhesive tape is a substrate. It does not peel off immediately.

The irradiation conditions of the light which hardens the said ultraviolet curable adhesive layer can be suitably adjusted with the combination of the said polymerizable polymer to be used, and the said ultraviolet polymerization initiator. For example, in the case of using a polymerizable polymer having an unsaturated double bond such as a vinyl group in a side chain and an ultraviolet polymerization initiator activated with a wavelength of 200 to 410 nm, irradiation with light of a wavelength of 365 nm or more The ultraviolet curable pressure sensitive adhesive layer can be crosslinked and cured.
For such an ultraviolet-curable pressure-sensitive adhesive layer, for example, irradiation with light having a wavelength of 365 nm is preferably performed with an illuminance of 5 mW or more, more preferably 10 mw or more, and is irradiated with an illuminance of 20 mW or more It is more preferable to do, and it is especially preferable to irradiate with the illumination intensity of 50 mW or more. In addition, it is preferable to irradiate light with a wavelength of 365 nm with an integrated illuminance of 300 mJ or more, more preferably with an integrated illuminance of 500 mJ or more and 10000 mJ or less, still more preferably with an integrated illuminance of 500 mJ or more and 7500 mJ or less It is particularly preferable to irradiate with an integrated illuminance of 1000 mJ or more and 5000 mJ or less.

In the method of manufacturing a semiconductor device according to the present invention, next, a supporting plate attaching step of attaching a supporting plate on the non-ultraviolet curable adhesive layer is performed.
In the present invention, the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape is divided into an ultraviolet-curable pressure-sensitive adhesive layer and a non-ultraviolet-curable pressure-sensitive adhesive layer. The curable pressure-sensitive adhesive layer does not cure. Therefore, the double-sided pressure-sensitive adhesive tape can be attached to the support plate with sufficient adhesive force. In addition, when a double-sided adhesive tape has the said ultraviolet-ray-permeable release film, the said release film is peeled by the time of the front of the said support plate sticking process after completion | finish of the said curing process.

Next, in the method of manufacturing a semiconductor device according to the present invention, a heat treatment step of processing the substrate at a high temperature of 150 ° C. or higher is performed.
Examples of the heat treatment step include a substrate manufacturing step and a chip mounting step. Heat treatment at 150 ° C. or higher is usually performed in the substrate manufacturing process, and heat treatment at 200 ° C. or higher is usually performed in the chip mounting step. In the method of manufacturing a semiconductor device according to the present invention, the UV curable adhesive layer is cured prior to the heat treatment step, so adhesion promotion is suppressed even when the treatment involving a high temperature of 150 ° C. or more is performed in the heat treatment step. The substrate can be easily peeled off after the processing is completed. In addition, since the ultraviolet-curable pressure-sensitive adhesive layer contains a silicone compound, adhesion can be further suppressed.

In the method of manufacturing a semiconductor device according to the present invention, the UV curable adhesive layer is then crosslinked and cured in the curing step including the peeling step of peeling the substrate from the double-sided adhesive tape. Can be peeled off easily while suppressing adhesive residue. In addition, since the time taken for peeling is shortened, the production efficiency can be increased.

According to the present invention, it is possible to protect the adherend with sufficient adhesive power, exhibit high heat resistance and adhesive residue suppression performance, and photocure the adhesive even when using a support plate that does not transmit light. It is possible to provide a non-support type double-sided pressure-sensitive adhesive tape and a method of manufacturing a semiconductor device using the double-sided pressure-sensitive adhesive tape.

EXAMPLES The embodiments of the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

Example 1
(Manufacture of non-UV curable adhesive)
In a reactor equipped with a thermometer, a stirrer and a condenser, 97 parts by weight of butyl acrylate as a (meth) acrylic acid alkyl ester, 3 parts by weight of acrylic acid as a carboxyl group-containing monomer and 120 parts by weight of ethyl acetate are added After that, the reactor was heated to start refluxing. Subsequently, 0.1 parts by weight of azobisisobutyronitrile as a polymerization initiator was added to the reactor. Refluxing was carried out at 70 ° C. for 5 hours to obtain a solution of (meth) acrylic copolymer. The weight-average molecular weight of the obtained (meth) acrylic copolymer was measured by a GPC method using “2690 Separations Model” manufactured by Water as a column and ethyl acetate as a solvent, and the weight average molecular weight was 800,000 using a polystyrene standard. The
The solid content ratio of an isocyanate crosslinking agent (Coronanate L, manufactured by Tosoh Corp.) relative to 100 parts by weight of the solid content of the (meth) acrylic copolymer contained in the obtained solution of the (meth) acrylic copolymer The mixture was stirred to obtain an ethyl acetate solution of a non-UV-curable adhesive ([-NCO / -OH] ratio: 0.7).

(Production of UV curable adhesive)
A reactor equipped with a thermometer, a stirrer, and a cooling tube is prepared. In this reactor, 94 parts by weight of 2-ethylhexyl acrylate as alkyl (meth) acrylate and 6 parts by weight of hydroxyethyl methacrylate as a functional group-containing monomer After adding 0.01 parts by weight of lauryl mercaptan and 80 parts by weight of ethyl acetate, the reactor was heated to start refluxing. Subsequently, 0.01 parts by weight of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane as a polymerization initiator is added to the above reactor, and polymerization is initiated under reflux. The Next, 0.01 parts by weight of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane is added one hour and two hours after the initiation of polymerization, and the polymerization is further initiated. After 4 hours, 0.05 parts by weight of t-hexylperoxypivalate was added to continue the polymerization reaction. Then, 8 hours after initiation of polymerization, an ethyl acetate solution of a functional group-containing (meth) acrylic polymer having a solid content of 55% by weight and a weight average molecular weight of 600,000 was obtained.
Reaction is performed by adding 3.5 parts by weight of 2-isocyanatoethyl methacrylate as a functional group-containing unsaturated compound to 100 parts by weight of resin solid content of an ethyl acetate solution containing the obtained functional group-containing (meth) acrylic polymer The resulting mixture was allowed to obtain a polymerizable polymer. Thereafter, 20 parts by weight of silicon diacrylate as a silicone compound, 20 parts by weight of silica filler, 0.7 parts by weight of isocyanate based crosslinking agent, 100 parts by weight of resin solid content of ethyl acetate solution of the obtained polymerizable polymer 1 part by weight of a polymerization initiator was mixed to obtain an ethyl acetate solution of a UV-curable pressure-sensitive adhesive. In addition, the following were used for the silicon diacrylate, a silica filler, an isocyanate type crosslinking agent, and a photoinitiator.
Silicon diacrylate: EBECRYL 350, manufactured by Daicel Ornex, weight average molecular weight 1000
Silica filler: Reoro seal MT-10, Isocyanate-based crosslinking agent manufactured by Tokuyama Co., Ltd .: Coronate L, Photopolymerization initiator manufactured by Japan Urethane Industrial Co., Ltd .: Esacure One, manufactured by Nippon Shiberehegner

(Manufacture of double-sided adhesive tape)
The resulting UV-curable pressure-sensitive adhesive solution is coated on a 50 μm polyethylene terephthalate (PET) film, one side of which has been subjected to a release treatment, with a doctor knife so that the thickness of the dry film is 40 μm, 110 ° C., The coating solution was dried by heating for 5 minutes to obtain a UV-curable pressure-sensitive adhesive layer.
The resulting non-UV-curable pressure-sensitive adhesive solution is coated on a 50 μm-thick transparent PET film on one side with a release treatment using a doctor knife so that the thickness of the dried film is 40 μm, 110 ° C. The coating solution was dried by heating for 5 minutes to obtain a non-UV-curable pressure-sensitive adhesive layer.
The surfaces of the obtained UV-curable pressure-sensitive adhesive layer and the non-UV-curable pressure-sensitive adhesive layer on which the PET films were not laminated were pasted together to obtain a double-sided pressure-sensitive adhesive tape.

(Measurement of gel fraction)
Using a high pressure mercury UV irradiator, adjust the illuminance so that the irradiation intensity of ultraviolet light of 365 nm on the surface of the double-sided adhesive tape is 100 mW / cm ^2, and irradiate 30 seconds from the non-UV curable adhesive layer side. The curable pressure-sensitive adhesive layer was crosslinked and cured. Thereafter, 0.1 g of only the UV curable adhesive layer was peeled off and immersed in 50 ml of ethyl acetate and shaken at a temperature of 23 ° C. and 200 rpm for 24 hours with a shaker (hereinafter, the peeled UV) The curable pressure-sensitive adhesive layer is referred to as a pressure-sensitive adhesive composition). After shaking, ethyl acetate and ethyl acetate were absorbed and a swollen adhesive composition was separated using a metal mesh (mesh size # 200 mesh). The separated pressure-sensitive adhesive composition was dried at 110 ° C. for 1 hour. The weight of the pressure-sensitive adhesive composition including the metal mesh after drying was measured, and the gel fraction of the ultraviolet-curable pressure-sensitive adhesive layer after ultraviolet curing was calculated using the following formula.
Gel fraction (% by weight) = 100 × (W ₁ −W ₂ ) / W ₀
(W ₀ : initial adhesive composition weight, W ₁ : adhesive composition weight including the metal mesh after drying, W ₂ : initial weight of the metal mesh)
Next, the gel fraction of the non-UV-curable pressure-sensitive adhesive layer was measured in the same manner. The results are shown in Tables 1 and 2.

(Measurement of adhesion of non-UV curable adhesive layer)
The double-sided pressure-sensitive adhesive tape was cut into strips of 5 mm width to prepare test pieces. After placing the test piece on the stainless steel plate so that the non-UV-curable pressure-sensitive adhesive layer faces the stainless steel plate, the test piece is reciprocated by one 2 kg rubber roller at a speed of 300 mm / min. And a stainless steel plate, and then allowed to stand at 23 ° C. for 24 hours to prepare a test sample. According to JIS Z0237, a tensile test in the direction of 180 ° was performed at a peeling speed of 300 mm / min, and an initial 180 ° peel strength (N / 5 mm) was measured. Then, the 180 ° peel adhesion with time was measured by the above method with respect to the double-sided adhesive tape stored at 40 ° C. for 1 month. The results are shown in Tables 1 and 2.

(Examples 2 to 6, Comparative Examples 1 to 4)
Both sides of the non-UV curable adhesive layer are the same as in Example 1 except that the blending amounts of butyl acrylate, acrylic acid and crosslinking agent and the silicone diacrylate content of the UV curable adhesive layer are as shown in Table 1. A pressure-sensitive adhesive tape was produced, and the gel fraction of each layer and the adhesion of the non-UV-curable pressure-sensitive adhesive layer were measured. In addition, E-5XM by the Soken chemical company was used as an epoxy-type crosslinking agent.

<Evaluation>
The pressure-sensitive adhesive compositions obtained in Examples and Comparative Examples were evaluated by the following methods. The results are shown in Tables 1 and 2.

(Evaluation of heat resistance)
The surface of the double-sided pressure-sensitive adhesive tape on the ultraviolet-curable pressure-sensitive adhesive layer side was attached to a substrate to obtain a laminate. Next, using a high-pressure mercury UV irradiator, the illuminance is adjusted so that the irradiation intensity of ultraviolet light of 365 nm on the surface of the semiconductor protective tape is 100 mW / cm ^2, and irradiation is performed for 30 seconds from the non-ultraviolet curable adhesive layer side. The UV-curable pressure-sensitive adhesive layer was crosslinked and cured. Thereafter, the non-UV-curable pressure-sensitive adhesive layer of the laminate was attached to a support plate made of aluminum, and heat treatment was carried out for three minutes at 260 ° C. for 6 minutes. After completion of the heat treatment, the double-sided pressure-sensitive adhesive tape was visually observed, and the initial heat resistance was evaluated as "o" when there was no peeling or void, and "x" when there was peeling or void. Moreover, time-lapse | temporal heat resistance evaluation was performed by the same method about what stored the double-sided adhesive tape for 40 degreeC and one month.

(Evaluation of adhesive residue)
The surface of the double-sided pressure-sensitive adhesive tape on the ultraviolet-curable pressure-sensitive adhesive layer side was attached to a substrate to obtain a laminate. Next, using a high-pressure mercury UV irradiator, the illuminance is adjusted so that the irradiation intensity of ultraviolet light of 365 nm on the surface of the semiconductor protective tape is 100 mW / cm ^2, and irradiation is performed for 30 seconds from the non-ultraviolet curable adhesive layer side. The UV-curable pressure-sensitive adhesive layer was crosslinked and cured. Thereafter, the non-UV-curable pressure-sensitive adhesive layer of the laminate was attached to a support plate made of aluminum, and heat treatment was performed at 240 ° C. for 1 hour. After the heat treatment, the double-sided pressure-sensitive adhesive tape was peeled off from the substrate. The substrate after peeling was visually observed, and the initial adhesive residue was evaluated as “o” when there was no adhesive residue and “x” when there was adhesive residue. Moreover, the time-lapse | temporal paste residue evaluation was performed by the same method about what stored the double-sided adhesive tape for 40 degreeC and one month.

(Evaluation of chemical resistance (flux) resistance)
A 10 cm × 10 cm double-sided adhesive tape was attached to the polyimide film, and a copper plate was attached to the other surface of the double-sided adhesive tape. The sample thus obtained was immersed in a detergent (Pine Alpha ST-180K) at 70 ° C. for 20 minutes. The sample was removed, and the sample was towel dried and then dried at 70 ° C. for 1 hour. The weight of the sample before immersion in the cleaning agent was W ₃ , and the weight of the sample after being immersed in the cleaning agent and dried was W ₄ , and the dissolution residue ratio was calculated according to the following equation.
Dissolving residue ratio _{(%) = [(W 3} -W 4) / W 3] × 100
The evaluation criteria were as follows.
◎: 100%, :: 97% or more and less than 100%, x: less than 97%

According to the present invention, it is possible to protect the adherend with sufficient adhesive power, exhibit high heat resistance and adhesive residue suppression performance, and photocure the adhesive even when using a support plate that does not transmit light. It is possible to provide a non-support type double-sided pressure-sensitive adhesive tape and a method of manufacturing a semiconductor device using the double-sided pressure-sensitive adhesive tape.

Claims (5)

A non-support type double-sided pressure-sensitive adhesive tape comprising a non-UV-curable non-UV-curable pressure-sensitive adhesive layer, and a UV-curable pressure-sensitive adhesive layer laminated on the non-UV-curable pressure-sensitive adhesive layer,
The UV-curable pressure-sensitive adhesive layer contains a UV-curable pressure-sensitive adhesive component and a silicone compound,
The non-UV-curable pressure-sensitive adhesive layer is
(A) (a) 92 to 97% by weight of (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms in alkyl group, and (b) 3.0 to 8.0% by weight of carboxyl group-containing monomer The double-sided adhesive tape which contains 100 weight part of (meth) acrylic-type copolymers contained as a component, and 0.5-5 weight part of (B) isocyanate type crosslinking agents. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the silicone compound is a silicone compound having a weight average molecular weight of 300 to 50,000 having a functional group crosslinkable with the ultraviolet curable adhesive component. The non-UV-curable pressure-sensitive adhesive layer according to claim 1 or 2, wherein the ratio of the hydroxyl group in the (meth) acrylic copolymer to the isocyanate group in the isocyanate-based crosslinking agent is 0.3 to 3.0. Double-sided adhesive tape. The gel fraction of the non-UV-curable pressure-sensitive adhesive layer is 60% or more, and the gel fraction of the UV-curable pressure-sensitive adhesive layer is 80% or more after UV curing. Double-sided adhesive tape as described. A substrate sticking step of sticking the double-sided pressure-sensitive adhesive tape according to any one of claims 1, 2, 3 or 4 from a UV-curable pressure-sensitive adhesive layer to a substrate;
A curing step of curing the UV-curable pressure-sensitive adhesive layer by irradiating UV light;
A support plate attaching step of attaching a support plate on the non-UV curable adhesive layer;
A method of manufacturing a semiconductor device, comprising: a heat treatment step of treating the substrate at a high temperature of 150 ° C. or more; and a peeling step of peeling the substrate from the double-sided pressure-sensitive adhesive tape.