JP6757743B2 - Semiconductor processing tape - Google Patents

Description

The present invention relates to a semiconductor processing tape, and more particularly to a semiconductor processing tape having a metal layer for protecting the back surface of a semiconductor chip mounted by a face down method.

In recent years, there has been an even greater demand for thinner and smaller semiconductor devices and their packages. Semiconductor devices are manufactured using a mounting method called the so-called face down method. The face-down method uses a semiconductor chip in which convex electrodes called bumps are formed on the circuit surface to ensure continuity, and the circuit surface is inverted (face-down) to connect the electrodes to the substrate (face-down method). So-called flip-chip connection).

In such a semiconductor device, the back surface of the semiconductor chip may be protected by a semiconductor processing tape to prevent damage to the semiconductor chip (see Patent Document 1). Further, it is also known that a single-sided adhesive film composed of a metal layer and an adhesive layer is attached onto the semiconductor element via the adhesive layer (see Patent Document 2).

As a typical procedure for flip-chip connection, a solder bump or the like formed on the surface of a semiconductor chip to which a semiconductor processing tape is adhered is immersed in a flux, and then the bump and an electrode formed on a substrate (if necessary, this). (Solder bumps are also formed on the electrodes) are brought into contact with each other, and finally the solder bumps are melted to reflow and connect the solder bumps and the electrodes. Flux is used for the purpose of cleaning solder bumps at the time of soldering, preventing oxidation, improving the wettability of solder, and the like. By the above procedure, a good electrical connection between the semiconductor chip and the substrate can be constructed.

Therefore, as a semiconductor processing tape capable of producing a semiconductor device having excellent appearance, which can prevent the occurrence of stains even if flux adheres, an adhesive layer and a protective layer laminated on the adhesive layer are used. A flip-chip type semiconductor back surface film having a protective layer made of a heat-resistant resin or metal having a glass transition temperature of 200 ° C. or higher has been proposed (see Patent Document 3).

JP-A-2007-158026 JP-A-2007-23502 Japanese Unexamined Patent Publication No. 2012-033266

When a resin containing a radiation-curable component or a thermosetting component is cured by radiation or heat to form a protective film as in Patent Document 1, the difference in thermal expansion coefficient between the cured protective film and the semiconductor wafer is large. Due to its large size, there is a problem that the semiconductor wafer or semiconductor chip during processing is warped.

However, in Patent Documents 2 and 3, the adhesive strength between the metal protective layer and the adhesive layer is not sufficient, and package cracks occur between the protective layer and the adhesive layer during packaging. , There was a problem that reliability was lowered. Further, Patent Document 3 also discloses a flip-chip type semiconductor back surface film in which a protective layer and an adhesive layer are provided on an adhesive layer of a dicing tape in which an adhesive layer is laminated on a base material. When such a flip-chip type semiconductor back surface film integrated with a dicing tape is used, the adhesive force between the protective layer and the adhesive layer is not sufficient, and when dicing the semiconductor wafer into individual pieces, the dicing tape is used. There is a problem that peeling occurs between the protective layer and the pressure-sensitive adhesive layer, and the semiconductor wafer cannot be satisfactorily separated.

Therefore, it is an object of the present invention to provide a semiconductor processing tape capable of satisfactorily fragmenting a semiconductor wafer during dicing and preventing the occurrence of package cracks during packaging. ..

In order to solve the above problems, the semiconductor processing tape according to the present invention includes a dicing tape having a base film and an adhesive layer, a metal layer provided on the adhesive layer, and a metal layer on the metal layer. It is provided and has an adhesive layer for adhering the metal layer to the back surface of the semiconductor chip, and the surface roughness RzJIS based on the ten-point average roughness of the metal layer is 0.5 μm or more and less than 10.0 μm. It is characterized by being.

In the semiconductor processing tape, the metal layer is preferably a copper foil.

Further, in the semiconductor processing tape, the adhesive layer contains (A) epoxy resin, (B) curing agent, (C) phenoxy resin, and (D) surface-treated inorganic filler. The content of D) is preferably 40% by weight or more and 65% by weight or less with respect to the total of (A) to (D).

Further, in the semiconductor processing tape, the pressure-sensitive adhesive layer contains an acrylic acid ester represented by CH ₂ = CHCOOR (in the formula, R is an alkyl group having 4 to 8 carbon atoms) and a hydroxyl group-containing monomer. And, it is preferable to contain an acrylic polymer composed of an isocyanate compound having a radically reactive carbon-carbon double bond in the molecule.

According to the present invention, the semiconductor wafer can be satisfactorily separated during dicing, and the occurrence of package cracks during packaging can be prevented.

It is sectional drawing which shows typically the structure of the semiconductor processing tape which concerns on embodiment of this invention. It is sectional drawing for demonstrating the usage method of the semiconductor processing tape which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail.

FIG. 1 is a cross-sectional view showing a semiconductor processing tape 10 according to an embodiment of the present invention. The semiconductor processing tape 10 has a dicing tape 13 composed of a base film 11 and an adhesive layer 12 provided on the base film 11, and a semiconductor chip C (on the pressure-sensitive adhesive layer 12). A metal layer 14 for protecting (see FIG. 2) and an adhesive layer 15 provided on the metal layer 14 are provided.

It is preferable that the surface of the adhesive layer 15 opposite to the surface in contact with the metal layer 14 is protected by a separator (release liner) (not shown). The separator has a function as a protective material that protects the adhesive layer 15 until it is put into practical use. Further, the separator can be used as a supporting base material when the metal layer 14 is attached to the pressure-sensitive adhesive layer 12 of the dicing tape 13 in the manufacturing process of the semiconductor processing tape 10.

The dicing tape 13, the metal layer 14, and the adhesive layer 15 may be pre-cut into a predetermined shape according to the process of use and the apparatus. Further, the semiconductor processing tape 10 of the present invention may be in the form of being cut for each semiconductor wafer W, or a long sheet in which a plurality of tapes cut for each semiconductor wafer W are formed. May be rolled up in a roll shape. Each component will be described below.

<Base film 11>
As the base film 11, any conventionally known one can be used without particular limitation, but when a radiation-curable material is used as the pressure-sensitive adhesive layer 12 described later, it has radiation permeability. It is preferable to use one.

For example, the materials thereof include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-acrylic. Methyl acid acid copolymer, ethylene-acrylic acid copolymer, homopolymer or copolymer of α-olefin such as ionomer or a mixture thereof, polyurethane, styrene-ethylene-butene or penten-based copolymer, polyamide-polypolymer Thermoplastic elastomers such as copolymers and mixtures thereof can be listed. Further, the base film 11 may be a mixture of two or more kinds of materials selected from these groups, or may be a single layer or a multi-layered film.

The thickness of the base film 11 is not particularly limited and may be set as appropriate, but is preferably 50 to 200 μm.

In order to improve the adhesion between the base film 11 and the pressure-sensitive adhesive layer 12, the surface of the base film 11 is chemically or physically treated with chromic acid, ozone, flame, high piezoelectric, ionizing radiation, etc. Surface treatment may be applied.

Further, in the present embodiment, the pressure-sensitive adhesive layer 12 is provided directly on the base film 11, but a prime layer for improving adhesion, an anchor layer for improving machinability during dicing, and stress. It may be provided indirectly via a relaxation layer, an antistatic layer, or the like.

<Adhesive layer 12>
The resin used for the pressure-sensitive adhesive layer 12 is not particularly limited, and known chlorinated polypropylene resin, acrylic resin, polyester resin, polyurethane resin, epoxy resin and the like used for the pressure-sensitive adhesive may be used. However, an acrylic pressure-sensitive adhesive using an acrylic polymer as a base polymer is preferable.

Examples of the acrylic polymer include (meth) acrylic acid alkyl esters (eg, methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, iso). Pentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester, tridecyl ester, tetradecyl ester, hexadecyl ester, Alkyl groups such as octadecyl esters and eicosyl esters have 1 to 30 carbon atoms, especially linear or branched alkyl esters having 4 to 18 carbon atoms) and (meth) acrylic acid cycloalkyl esters (eg, cyclopentyl esters). , Cyclohexyl ester, etc.), and acrylic polymers using one or more of them as monomer components. The (meth) acrylic acid ester means an acrylic acid ester and / or a methacrylic acid ester, and all of the (meta) of the present invention have the same meaning.

The acrylic polymer contains a unit corresponding to the (meth) acrylic acid alkyl ester or other monomer component copolymerizable with the cycloalkyl ester, if necessary, for the purpose of modifying the cohesive force, heat resistance, etc. You may. Examples of such monomer components include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride. , Acid anhydride monomers such as itaconic acid anhydride; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate. , (Meta) acrylate 8-hydroxyoctyl, (meth) acrylate 10-hydroxydecyl, (meth) acrylate 12-hydroxylauryl, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate and other hydroxyl group-containing monomers; Sulfonic acid groups such as styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalene sulfonic acid. Containing monomer; Phosphonic acid group-containing monomer such as 2-hydroxyethylacryloyl phosphate; acrylamide, acrylonitrile and the like. One or two or more of these copolymerizable monomer components can be used. The amount of these copolymerizable monomers used is preferably 40% by weight or less of the total monomer components.

Further, since the acrylic polymer is crosslinked, a polyfunctional monomer or the like can be included as a monomer component for copolymerization, if necessary. Examples of such a polyfunctional monomer include hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, and neopentyl glycol di (meth) acrylate. Pentaerythritol di (meth) acrylate, trimethylolpropanthry (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) Examples include acrylate. One or more of these polyfunctional monomers can also be used. The amount of the polyfunctional monomer used is preferably 30% by weight or less of the total monomer components from the viewpoint of adhesive properties and the like.

The acrylic polymer can be prepared, for example, by applying an appropriate method such as a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, or a suspension polymerization method to a mixture of one or more kinds of component monomers. The pressure-sensitive adhesive layer 12 preferably has a composition in which the content of low molecular weight substances is suppressed from the viewpoint of preventing contamination of the wafer, and from this point, the main component is an acrylic polymer having a weight average molecular weight of 300,000 or more, particularly 400,000 to 3 million. The pressure-sensitive adhesive may be an appropriate cross-linking type by an internal cross-linking method, an external cross-linking method, or the like.

Further, in order to control the crosslink density of the pressure-sensitive adhesive layer 12 and improve the pick-up property, for example, a polyfunctional isocyanate compound, a polyfunctional epoxy compound, a melamine compound, a metal salt compound, a metal chelate compound, and an amino resin compound. A method of cross-linking with a compound or an appropriate external cross-linking agent such as peroxide, or a method of mixing low molecular weight compounds having two or more carbon-carbon double bonds and cross-linking by irradiation with energy rays or the like. Etc., an appropriate method can be adopted. When an external cross-linking agent is used, the amount used is appropriately determined depending on the balance with the base polymer to be cross-linked and further depending on the intended use as an adhesive. Generally, it is preferably blended in an amount of about 5 parts by weight or less, more preferably 0.1 parts by weight to 5 parts by weight, based on 100 parts by weight of the base polymer. In addition to the above-mentioned components, various tackifiers, antiaging agents, and other additives may be used as the pressure-sensitive adhesive, if necessary, from the viewpoint of preventing deterioration and the like.

As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 12, a radiation-curable pressure-sensitive adhesive is suitable. Examples of the radiation-curable pressure-sensitive adhesive include an additive-type radiation-curable pressure-sensitive adhesive in which a radiation-curable monomer component and a radiation-curable oligomer component are mixed with the above-mentioned pressure-sensitive adhesive.

Examples of the radiation-curable monomer component to be blended include urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaeristol tetra (). Examples thereof include meta) acrylate, dipentaeristol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and 1,4-butanediol di (meth) acrylate. These monomer components can be used alone or in combination of two or more.

Further, examples of the radiation-curable oligomer component include various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based, and those having a molecular weight in the range of about 100 to 30,000 are suitable. The amount of the radiation-curable monomer component or oligomer component to be blended can be appropriately determined according to the type of the pressure-sensitive adhesive layer so that the adhesive strength of the pressure-sensitive adhesive layer can be reduced. Generally, it is, for example, about 5 parts by weight to 500 parts by weight, preferably about 70 parts by weight to 150 parts by weight, based on 100 parts by weight of a base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

As the radiation-curable pressure-sensitive adhesive, in addition to the addition-type radiation-curable pressure-sensitive adhesive, a base polymer having a carbon-carbon double bond in the side chain or main chain or at the end of the main chain was used. Intrinsic radiation curable adhesives can also be mentioned. Since the intrinsic radiation-curable pressure-sensitive adhesive does not need to contain the oligomer component, which is a low-molecular component, or does not contain a large amount, the oligomer component, etc. does not move in the pressure-sensitive adhesive over time and is stable. It is preferable because an adhesive layer having a layered structure can be formed.

As the base polymer having a carbon-carbon double bond, a polymer having a carbon-carbon double bond and having adhesiveness can be used without particular limitation. As such a base polymer, one having an acrylic polymer as a basic skeleton is preferable. Examples of the basic skeleton of the acrylic polymer include the above-exemplified acrylic polymer.

The method for introducing a carbon-carbon double bond into an acrylic polymer is not particularly limited, and various methods can be adopted, but it is easy to introduce a carbon-carbon double bond into the polymer side chain in terms of molecular design. is there. For example, after copolymerizing a monomer having a functional group with an acrylic polymer in advance, a compound having a functional group capable of reacting with the functional group and a carbon-carbon double bond is subjected to radiation curability of the carbon-carbon double bond. A method of condensing or adding reaction while maintaining the above can be mentioned.

Examples of the combination of these functional groups include a carboxylic acid group and an epoxy group, a carboxylic acid group and an aziridyl group, a hydroxyl group and an isocyanate group, and the like. Among these combinations of functional groups, a combination of a hydroxyl group and an isocyanate group is preferable because of ease of reaction tracking. Further, as long as the combination of these functional groups produces an acrylic polymer having the carbon-carbon double bond, the functional group may be on either side of the acrylic polymer or the compound. In the above preferred combination, it is preferable that the acrylic polymer has a hydroxyl group and the compound has an isocyanate group. In this case, examples of the isocyanate compound having a carbon-carbon double bond include methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α, α-dimethylbenzyl isocyanate and the like. Further, as the acrylic polymer, one obtained by copolymerizing the above-exemplified hydroxy group-containing monomer, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, ether compound of diethylene glucol monovinyl ether and the like is used.

In the intrinsic radiation-curable pressure-sensitive adhesive, the base polymer having a carbon-carbon double bond (particularly an acrylic polymer) can be used alone, but the radiation-curable monomer component does not deteriorate the properties. And photopolymerizable compounds such as oligomer components can also be blended. The blending amount of the photopolymerizable compound is usually in the range of 30 parts by weight or less, preferably in the range of 0 to 10 parts by weight, based on 100 parts by weight of the base polymer.

The radiation-curable pressure-sensitive adhesive preferably contains a photopolymerization initiator when it is cured by ultraviolet rays or the like.

Among the above-mentioned acrylic polymers, in particular, an acrylic acid ester represented by CH ₂ = CHCOOR (in the formula, R is an alkyl group having 4 to 8 carbon atoms), a hydroxyl group-containing monomer, and intramolecules. Acrylic polymer A composed of an isocyanate compound having a radically reactive carbon-carbon double bond is preferable.

If the alkyl group of the acrylic acid alkyl ester has less than 4 carbon atoms, the polarity may be high and the peeling force may be too large to reduce the pick-up property. On the other hand, when the number of carbon atoms of the alkyl group of the acrylic acid alkyl ester exceeds 8, the tack of the pressure-sensitive adhesive layer 12 becomes small, so that the adhesiveness or adhesion to the metal layer 15 decreases, and as a result, during dicing. Peeling of the metal layer 15 may occur.

The acrylic polymer A may contain units corresponding to other monomer components, if necessary.

In the acrylic polymer A, an isocyanate compound having a radically reactive carbon-carbon double bond is used. That is, it is preferable that the acrylic polymer has a structure in which a double bond-containing isocyanate compound is added to a polymer composed of a monomer composition such as the acrylic acid ester or a hydroxyl group-containing monomer. Therefore, it is preferable that the acrylic polymer has a radical-reactive carbon-carbon double bond in its molecular structure. As a result, the active energy ray-curable pressure-sensitive adhesive layer (ultraviolet-curable pressure-sensitive adhesive layer, etc.) that is cured by irradiation with active energy rays (ultraviolet rays, etc.) can be formed, and the peeling force between the metal layer 15 and the pressure-sensitive adhesive layer 12 can be obtained. Can be reduced.

Examples of the double bond-containing isocyanate compound include methacryloyl isocyanate, acryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, 2-acryloyloxyethyl isocyanate, m-isopropenyl-α, α-dimethylbenzyl isocyanate and the like. The double bond-containing isocyanate compound can be used alone or in combination of two or more.

Further, in the active energy ray-curable pressure-sensitive adhesive, an external cross-linking agent can be appropriately used in order to adjust the adhesive strength before irradiation with active energy rays and the adhesive strength after irradiation with active energy rays. Specific means of the external cross-linking method include a method of adding a so-called cross-linking agent such as a polyisocyanate compound, an epoxy compound, an aziridine compound, and a melamine-based cross-linking agent to cause a reaction. When an external cross-linking agent is used, the amount used is appropriately determined depending on the balance with the base polymer to be cross-linked and further depending on the intended use as an adhesive. The amount of the external cross-linking agent used is generally 20 parts by weight or less (preferably 0.1 parts by weight to 10 parts by weight) with respect to 100 parts by weight of the base polymer. Further, if necessary, the active energy ray-curable pressure-sensitive adhesive may contain various conventionally known additives such as a pressure-imparting agent, an antiaging agent, and a foaming agent, in addition to the above-mentioned components.

The thickness of the pressure-sensitive adhesive layer 12 is not particularly limited and can be appropriately determined, but is generally about 5 to 200 μm. Further, the pressure-sensitive adhesive layer 12 may be composed of a single layer or a plurality of layers.

<Metal layer 14>
The metal constituting the metal layer 14 is not particularly limited, and for example, the laser may be at least one metal selected from the group consisting of aluminum, iron, titanium, tin, nickel and copper and / or an alloy thereof. It is preferable from the viewpoint of marking property. Among these, copper, aluminum or their alloys have high thermal conductivity, and the effect of heat dissipation through the metal layer can also be obtained. In addition, copper, aluminum, iron, nickel or their alloys also have an effect of suppressing warpage of electronic device packages.

The surface roughness RzJIS based on the ten-point average roughness of the metal layer 14 is 0.5 μm or more and less than 10.0 μm. By setting the surface roughness RzJIS to 0.5 μm or more, the contact area between the metal layer 14 and the adhesive layer 15 becomes large, and the metal layer 14 and the adhesive layer 15 have an anchor effect due to the unevenness of the surface of the metal layer 14. The metal layer 14 can be prevented from peeling off due to the load from the dicing blade or the water flow of the cutting water, and the adhesive layer is firmly bonded after curing, so packaging or reliability. It is possible to prevent the occurrence of package cracks during the sex test. Further, the surface roughness RzJIS is preferably 1.0 μm or more, and when it is 2.0 μm or more, the anchor effect is more exerted, which is preferable. Further, when the surface roughness RzJIS is less than 10.0 μm, the adhesive or the adhesive can enter the unevenness of the surface of the metal layer 14. If the adhesive does not enter the unevenness of the surface of the metal layer 14, that part becomes a void (void), and this void becomes the starting point of the popcorn phenomenon (steam explosion) during reflow or reliability test, and package cracks occur. It will occur. The surface roughness RzJIS in this specification is the ten-point average roughness specified in Annex JA of JIS B 0601: 2013.

The thickness of the metal layer 14 can be appropriately determined in consideration of the handleability and workability of the semiconductor wafer W or the semiconductor chip C, and is usually in the range of 2 to 200 μm. When the metal layer is 200 μm or less, the winding process is easy, and when it is 50 μm or less, it is preferable because it can contribute to the thinning of the semiconductor package. On the other hand, from the viewpoint of handleability, at least 2 μm or more is required.

<Adhesive layer 15>
The adhesive layer 15 is a film formed of an adhesive in advance.

The adhesive layer 15 is formed of at least a thermosetting resin, and is preferably formed of at least a thermosetting resin and a thermoplastic resin.

Examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, and polycarbonate resin. Thermoplastic polyimide resin, polyamide resin such as 6-nylon and 6,6-nylon, phenoxy resin, acrylic resin, saturated polyester resin such as PET (polyethylene terephthalate) and PBT (polybutylene terephthalate), polyamideimide resin, or fluororesin And so on. The thermoplastic resin can be used alone or in combination of two or more. Among these thermoplastic resins, acrylic resin has less ionic impurities and excellent stress relaxation property, and phenoxy resin has high toughness while achieving both flexibility and strength. This is particularly preferable because reliability can be easily ensured.

The acrylic resin is not particularly limited, and is linear or branched having 30 or less carbon atoms (preferably 4 to 18 carbon atoms, more preferably 6 to 10 carbon atoms, particularly preferably 8 or 9 carbon atoms). Examples thereof include a polymer containing one or more kinds of acrylic acid or methacrylic acid ester having an alkyl group as a component. That is, in the present invention, acrylic resin has a broad meaning including methacrylic resin. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a t-butyl group, an isobutyl group, a pentyl group, an isopentyl group, a hexyl group, a heptyl group and a 2-ethylhexyl group. , Octyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, dodecyl group (lauryl group), tridecyl group, tetradecyl group, stearyl group, octadecyl group and the like.

Further, the other monomer for forming the acrylic resin (a monomer other than the alkyl ester of acrylic acid or methacrylic acid having an alkyl group having 30 or less carbon atoms) is not particularly limited, and for example, acrylic acid. Carboxyl group-containing monomers such as methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid or crotonic acid, acid anhydride monomers such as maleic anhydride or itaconic anhydride, (meth) 2-Hydroxyethyl acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, (meth) Hydroxyl group-containing monomers such as 10-hydroxydecyl acrylate, 12-hydroxylauryl (meth) acrylate or (4-hydroxymethylcyclohexyl) -methylacrylate, styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide -2-Methylpropanesulfonic acid, (meth) acrylamidepropanesulfonic acid, sulfopropyl (meth) acrylate, sulfonic acid group-containing monomers such as (meth) acryloyloxynaphthalene sulfonic acid, or 2-hydroxyethylacryloyl phosphate, etc. Examples thereof include sulfonic acid group-containing monomers. In addition, (meth) acrylic acid means acrylic acid and / or methacrylic acid, and all have the same meaning as (meth) of the present invention.

Examples of the thermosetting resin include epoxy resin, phenol resin, amino resin, unsaturated polyester resin, polyurethane resin, silicone resin, thermosetting polyimide resin and the like. The thermosetting resin can be used alone or in combination of two or more. As the thermosetting resin, an epoxy resin containing a small amount of ionic impurities and the like that corrode semiconductor elements is particularly preferable. Further, a phenol resin can be preferably used as the curing agent for the epoxy resin.

The epoxy resin is not particularly limited, and for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, brominated bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol AF type epoxy. Bifunctional epoxy such as resin, biphenyl type epoxy resin, naphthalene type epoxy resin, fluorene type epoxy resin, phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, trishydroxyphenylmethane type epoxy resin, tetraphenylol ethane type epoxy resin, etc. An epoxy resin such as a resin, a polyfunctional epoxy resin, a hidden-in type epoxy resin, a trisglycidyl isocyanurate type epoxy resin, or a glycidylamine type epoxy resin can be used.

As the epoxy resin, a novolak type epoxy resin, a biphenyl type epoxy resin, a trishydroxyphenylmethane type epoxy resin, and a tetraphenylolethane type epoxy resin are particularly preferable. This is because these epoxy resins are highly reactive with phenolic resins as curing agents and are excellent in heat resistance and the like.

Further, the phenol resin acts as a curing agent for the epoxy resin, and for example, a novolak type phenol resin such as a phenol novolac resin, a phenol aralkyl resin, a cresol novolac resin, a tert-butylphenol novolak resin, and a nonylphenol novolak resin, and a resole type. Examples thereof include phenolic resin and polyoxystyrene such as polyparaoxystyrene. The phenolic resin can be used alone or in combination of two or more. Of these phenolic resins, phenol novolac resin and phenol aralkyl resin are particularly preferable. This is because the connection reliability of the semiconductor device can be improved.

The mixing ratio of the epoxy resin and the phenol resin is preferably, for example, such that the hydroxyl groups in the phenol resin are 0.5 equivalents to 2.0 equivalents per 1 equivalent of the epoxy groups in the epoxy resin component. More preferred are 0.8 equivalents to 1.2 equivalents. That is, if the blending ratio of both is out of the above range, the curing reaction does not proceed sufficiently, and the characteristics of the cured epoxy resin product are likely to deteriorate.

Further, a thermosetting catalyst of epoxy resin and phenol resin may be used. The thermosetting accelerator is not particularly limited, and can be appropriately selected and used from known thermosetting accelerators. The thermosetting accelerator can be used alone or in combination of two or more. As the thermosetting accelerator, for example, an amine-based curing accelerator, a phosphorus-based curing accelerator, an imidazole-based curing accelerator, a boron-based curing accelerator, a phosphorus-boron-based curing accelerator, or the like can be used.

As the curing agent for the epoxy resin, it is preferable to use a phenol resin as described above, but known curing agents such as imidazoles, amines and acid anhydrides can also be used.

It is important that the adhesive layer 15 has adhesiveness (adhesion) to the back surface (non-circuit-formed surface) of the semiconductor wafer. Therefore, in order to crosslink the adhesive layer 15 to some extent in advance, a polyfunctional compound that reacts with a functional group at the end of the molecular chain of the polymer may be added as a crosslinking agent. This makes it possible to improve the adhesive properties at high temperatures and improve the heat resistance.

The cross-linking agent is not particularly limited, and a known cross-linking agent can be used. Specifically, for example, in addition to isocyanate-based cross-linking agents, epoxy-based cross-linking agents, melamine-based cross-linking agents and peroxide-based cross-linking agents, urea-based cross-linking agents, metal alkoxide-based cross-linking agents, metal chelate-based cross-linking agents, and metal salts Examples thereof include a system cross-linking agent, a carbodiimide-based cross-linking agent, an oxazoline-based cross-linking agent, an aziridine-based cross-linking agent, and an amine-based cross-linking agent. As the cross-linking agent, an isocyanate-based cross-linking agent or an epoxy-based cross-linking agent is suitable. In addition, the cross-linking agent can be used alone or in combination of two or more.

In the present invention, instead of using a cross-linking agent, or while using a cross-linking agent, it is also possible to carry out the cross-linking treatment by irradiation with an electron beam, ultraviolet rays, or the like.

Other additives can be appropriately added to the adhesive layer 15 as needed. Examples of other additives include fillers, flame retardants, silane coupling agents, ion trapping agents, bulking agents, antiaging agents, antioxidants, surfactants and the like.

The filler may be either an inorganic filler or an organic filler, but the inorganic filler is preferable. By blending a filler such as an inorganic filler, it is possible to improve the thermal conductivity of the adhesive layer 15 and adjust the elastic modulus. Examples of the inorganic filler include ceramics such as silica, clay, gypsum, calcium carbonate, barium sulfate, alumina, beryllium oxide, silicon carbide, and silicon nitride, aluminum, copper, silver, gold, nickel, chromium, lead, and tin. , Zinc, palladium, metals such as solder, alloys, and various other inorganic powders made of carbon and the like. The filler can be used alone or in combination of two or more. Among them, silica or alumina is preferable as the filler, and molten silica is particularly preferable as the silica. The average particle size of the inorganic filler is preferably in the range of 0.1 μm to 80 μm. The average particle size of the inorganic filler can be measured by, for example, a laser diffraction type particle size distribution measuring device.

The blending amount of the filler (particularly the inorganic filler) is preferably 80% by weight or less (0% by weight to 80% by weight), particularly 0% by weight to 70% by weight, based on the organic resin component. Suitable.

Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resin. The flame retardant can be used alone or in combination of two or more. Examples of the silane coupling agent include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane and the like. The silane coupling agent can be used alone or in combination of two or more. Examples of the ion trap agent include hydrotalcites, bismuth hydroxide and the like. The ion trap agent can be used alone or in combination of two or more.

The adhesive layer 15 contains, in particular, (A) epoxy resin, (B) curing agent, (C) phenoxy resin, and (D) surface-treated inorganic filler from the viewpoint of adhesiveness and reliability. The content of D) is preferably 40% by weight or more and 65% by weight or less with respect to the total of (A) to (D).

By using the epoxy resin (A), high adhesiveness, water resistance, and heat resistance can be obtained. As the epoxy resin, the above-mentioned known epoxy resin can be used. (B) As the curing agent, the above-mentioned known curing agent can be used.

(C) The phenoxy resin has a long molecular chain and is similar in structure to the epoxy resin. It acts as a flexible material in a composition having a high crosslink density and imparts high toughness, so that it has high strength and toughness. Composition is obtained. The preferred phenoxy resin has a main skeleton of bisphenol A type, and other commercially available phenoxy resins such as bisphenol F type phenoxy resin, bisphenol A / F mixed phenoxy resin and brominated phenoxy resin can be mentioned as preferable ones.

Examples of the surface-treated inorganic filler (D) include an inorganic filler surface-treated with a silane coupling agent. As the inorganic filler, the above-mentioned known inorganic filler can be used, but silica and alumina are preferable. By surface-treating with a silane coupling agent, the dispersibility of the inorganic filler is improved. Therefore, since it is excellent in fluidity, the adhesive force with the metal layer can be improved. Further, since the inorganic filler can be highly filled, the water absorption rate can be lowered and the moisture resistance can be improved.

The surface treatment of the inorganic filler with the silane coupling agent is carried out by dispersing the inorganic filler in the silane coupling agent solution by a known method, whereby the hydroxyl group existing on the surface of the inorganic filler and the alkoxy of the silane coupling agent are used. It is carried out by reacting a hydrolyzed group such as a group with a hydrolyzed silanol group to form a Si—O—Si bond on the surface of the inorganic filler.

The content of (D) surface-treated inorganic filler is 40 weights based on the total of (A) epoxy resin, (B) curing agent, (C) phenoxy resin, and (D) surface-treated inorganic filler. When it is set to% or more, the water absorption rate and the saturated moisture absorption rate can be lowered, the thermal conductivity of the adhesive layer is improved, and the effect of heat dissipation via the metal layer can be obtained, which is preferable. The content of (D) surface-treated inorganic filler is 65 weight based on the total of (A) epoxy resin, (B) curing agent, (C) phenoxy resin, and (D) surface-treated inorganic filler. When it is set to% or less, the fluidity due to the resin component can be ensured, which is preferable in that the adhesive strength to the metal layer or the wafer is excellent.

The thickness of the adhesive layer 15 is not particularly limited, but is usually preferably 3 μm or more, more preferably 5 μm or more, and preferably 100 μm or less in order to contribute to the thinning of the semiconductor package, from the viewpoint of handleability. More preferably, it is 50 μm or less. Further, it is preferable that the metal layer 14 has a thickness equal to or higher than the surface roughness RzJIS based on the ten-point average roughness. When the thickness of the adhesive layer 15 is equal to or greater than the surface roughness RzJIS, it easily penetrates into the unevenness of the surface of the metal layer 14, and the anchor effect can be easily obtained. Further, the adhesive layer 15 may be composed of a single layer or a plurality of layers.

Further, the adhesive layer 15 has a peeling force (23 ° C., peeling angle 180 degrees, linear speed 300 mm / min) of 0.3 N or more from the metal layer 14 in the B stage (uncured state or semi-cured state). Is preferable. If the peeling force is less than 0.3 N, peeling occurs between the semiconductor wafer W or the semiconductor chip C and the adhesive layer 15 or between the adhesive layer 15 and the metal layer 14 when dicing the semiconductor wafer W. This may result in chipping of the semiconductor chip C.

The water absorption rate of the adhesive layer 15 is preferably 1.5 vol% or less. The method for measuring the water absorption rate is as follows. That is, using an adhesive layer 15 (film-like adhesive) having a size of 50 × 50 mm as a sample, the sample is dried at 120 ° C. for 3 hours in a vacuum dryer, allowed to cool in a desiccator, and then the dry mass is measured. Let's call it M1. The sample is immersed in distilled water at room temperature for 24 hours and then taken out, the surface of the sample is wiped off with a filter paper, and the sample is quickly weighed to obtain M2. The water absorption rate is calculated by the following equation (1).
Water absorption rate (vol%) = [(M2-M1) / (M1 / d)] x 100 (1)
Here, d is the density of the film.
If the water absorption rate exceeds 1.5 vol%, package cracks may occur during solder reflow due to the absorbed water.

ここで、ｄはフィルムの密度である。
飽和吸湿率が１．０ｖｏｌ％を超えると、リフロー時の吸湿により蒸気圧の値が高くなり、良好なリフロー特性が得られないおそれがある。The saturated hygroscopicity of the adhesive layer 15 is preferably 1.0 vol% or less. The method for measuring the saturated hygroscopicity is as follows. That is, using a circular adhesive layer 15 (film-like adhesive) having a diameter of 100 mm as a sample, the sample was dried at 120 ° C. for 3 hours in a vacuum dryer, allowed to cool in a desiccator, and then the dry mass was measured to obtain M1. To do. The sample is absorbed in a constant temperature and humidity chamber at 85 ° C. and 85% RH for 168 hours, then taken out and quickly weighed to obtain M2. The saturated hygroscopicity is calculated by the following equation (2).

Here, d is the density of the film.
If the saturated moisture absorption rate exceeds 1.0 vol%, the value of the vapor pressure becomes high due to the moisture absorption during reflow, and good reflow characteristics may not be obtained.

The residual volatile content of the adhesive layer 15 is preferably 3.0 wt% or less. The method for measuring the residual volatile components is as follows. That is, an adhesive layer 15 (film-like adhesive) having a size of 50 × 50 mm was used as a sample, the initial mass of the sample was measured to obtain M1, and the sample was heated at 200 ° C. for 2 hours in a hot air circulation constant temperature bath. Weigh it to M2. The residual volatile content is calculated by the following formula (3).
Residual volatilization (wt%) = [(M2-M1) / M1] x 100 (3)
If the residual volatile content exceeds 3.0 wt%, the solvent may volatilize due to heating during packaging, voids may be generated inside the adhesive layer 15, and package cracks may occur.

The ratio of the linear expansion coefficient of the metal layer 14 to the linear expansion coefficient of the adhesive layer 15 (the linear expansion coefficient of the metal layer 14 / the linear expansion coefficient of the adhesive layer 15) is preferably 0.2 or more. If the ratio is less than 0.2, peeling is likely to occur between the metal layer 14 and the adhesive layer 15, package cracks may occur during packaging, and reliability may decrease.

(Separator)
The separator is for improving the handleability of the adhesive layer 15 and protecting the adhesive layer 15. As the separator, polyester (PET, PBT, PEN, PBN, PTT) -based, polyolefin (PP, PE) -based, copolymer (EVA, EEA, EBA) -based, and these materials are partially substituted, and further. A film with improved adhesiveness and mechanical strength can be used. Further, it may be a laminate of these films.

The thickness of the separator is not particularly limited and may be set as appropriate, but is preferably 25 to 50 μm.

(Semiconductor processing tape 10)
A method for manufacturing the semiconductor processing tape 10 according to the present embodiment will be described. First, the adhesive layer 15 can be formed by using a conventional method in which a resin composition is prepared and formed into a film-like layer. Specifically, for example, the resin composition is applied onto an appropriate separator (release paper, etc.) and dried (when thermosetting is required, heat treatment is applied and dried as necessary). Examples thereof include a method of forming the adhesive layer 15. The resin composition may be a solution or a dispersion. Next, the obtained adhesive layer 15 and the separately prepared metal layer 14 are bonded together. As the metal layer 14, a commercially available metal foil may be used. After that, the adhesive layer 15 and the metal layer 14 are precut into a circular label shape having a predetermined size using a push-cutting blade to remove unnecessary portions around the adhesive layer 15.

Next, the dicing tape 13 is produced. The base film 11 can be formed by a conventionally known film forming method. Examples of the film forming method include a calendar film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T-die extrusion method, a coextrusion method, and a dry laminating method. Next, the pressure-sensitive adhesive composition is applied onto the base film 11 and dried (by heat-crosslinking if necessary) to form the pressure-sensitive adhesive layer 12. Examples of the coating method include roll coating, screen coating, and gravure coating. The pressure-sensitive adhesive composition may be directly applied to the base film 11 to form the pressure-sensitive adhesive layer 12 on the base film 11, or the release paper obtained by peeling the surface of the pressure-sensitive adhesive composition. Etc. may be applied to form the pressure-sensitive adhesive layer 12, and then the pressure-sensitive adhesive layer 12 may be transferred to the base film 11. As a result, the dicing tape 13 in which the pressure-sensitive adhesive layer 12 is formed on the base film 11 is produced.

After that, the dicing tape 13 is laminated on the separator provided with the circular metal layer 14 and the adhesive layer 15 so that the metal layer 14 and the adhesive layer 12 are in contact with each other, and in some cases, the dicing tape 13 also has a predetermined size. The semiconductor processing tape 10 is produced by pre-cutting into a circular label shape or the like.

<How to use>
Next, a method of manufacturing a semiconductor device using the semiconductor processing tape 10 of the present embodiment will be described with reference to FIG.

The method for manufacturing a semiconductor device includes a step of attaching a semiconductor wafer W on a semiconductor processing tape 10 integrated with a dicing tape (mounting step) and a step of dicing the semiconductor wafer W to form a semiconductor chip C (dicing step). ), A step of peeling the semiconductor chip C from the adhesive layer 12 of the dicing tape 13 together with the semiconductor processing tape 10 (pickup step), and a step of flip-chip connecting the semiconductor chip C onto the adherend 16 (flip chip). The connection process) is provided at least.

[Mounting process]
First, a separator arbitrarily provided on the semiconductor processing tape 10 integrated with the dicing tape is appropriately peeled off, and the semiconductor wafer W is attached to the adhesive layer 15 as shown in FIG. 2 (A). , This is adhesively held and fixed (mounting process). At this time, the adhesive layer 15 is in an uncured state (including a semi-cured state). Further, the semiconductor processing tape 10 integrated with the dicing tape is attached to the back surface of the semiconductor wafer W. The back surface of the semiconductor wafer W means a surface opposite to the circuit surface (also referred to as a non-circuit surface, a non-electrode forming surface, or the like). The sticking method is not particularly limited, but a crimping method is preferable. The crimping is usually performed while pressing with a pressing means such as a crimping roll.

[Dicing process]
Next, as shown in FIG. 2B, dicing of the semiconductor wafer W is performed. As a result, the semiconductor wafer W is cut into a predetermined size and individualized (small pieces) to manufacture the semiconductor chip C. Dicing is performed, for example, from the circuit surface side of the semiconductor wafer W according to a conventional method. Further, in this step, for example, a cutting method called full cut that cuts up to the semiconductor processing tape 10 can be adopted. The dicing apparatus used in this step is not particularly limited, and conventionally known dicing apparatus can be used. Further, since the semiconductor wafer W is adhesively fixed by the semiconductor processing tape 10 with excellent adhesion, chip chipping and chip skipping can be suppressed, and damage to the semiconductor wafer W can also be suppressed. When expanding the semiconductor processing tape 10 integrated with the dicing tape, the expansion can be performed using a conventionally known expanding device.

[Pickup process]
As shown in FIG. 2C, the semiconductor chip C is picked up and the semiconductor chip C is peeled off from the dicing tape 13 together with the adhesive layer 15 and the metal layer 14. The pick-up method is not particularly limited, and various conventionally known methods can be adopted. For example, a method in which each semiconductor chip C is pushed up from the base film 11 side of the semiconductor processing tape 10 by a needle and the pushed up semiconductor chip C is picked up by a pickup device and the like can be mentioned. The back surface of the picked up semiconductor chip C is protected by the metal layer 14.

[Flip chip connection process]
As shown in FIG. 2D, the picked-up semiconductor chip C is fixed to an adherend 16 such as a substrate by a flip chip bonding method (flip chip mounting method). Specifically, the semiconductor chip C is always attached to the adherend 16 in a form in which the circuit surface (also referred to as a surface, a circuit pattern forming surface, an electrode forming surface, etc.) of the semiconductor chip C faces the adherend 16. Fix according to the law. For example, first, flux is attached to the bump 17 as a connecting portion formed on the circuit surface side of the semiconductor chip C. Next, the bump 17 of the semiconductor chip C is brought into contact with the conductive material 18 (solder or the like) for joining attached to the connection pad of the adherend 16 and pressed to melt the bump 17 and the conductive material 18. The electrical conduction between the semiconductor chip C and the adherend 16 can be ensured, and the semiconductor chip C can be fixed to the adherend 16 (flip chip bonding step). At this time, a gap is formed between the semiconductor chip C and the adherend 16, and the gap distance thereof is generally about 30 μm to 300 μm. After the semiconductor chip C is flip-chip bonded (flip-chip connected) on the adherend 16, the flux remaining on the facing surface or the gap between the semiconductor chip C and the adherend 16 is washed and removed to form the gap. Fill with a sealing material (sealing resin, etc.) and seal.

As the adherend 16, various substrates such as a lead frame and a circuit board (wiring circuit board, etc.) can be used. The material of such a substrate is not particularly limited, and examples thereof include a ceramic substrate and a plastic substrate. Examples of the plastic substrate include an epoxy substrate, a bismaleimide triazine substrate, a polyimide substrate and the like. Further, a chip-on-chip structure can be obtained by using another semiconductor chip as the adherend 16 and connecting the semiconductor chip C with a flip chip.

<Example>
Next, in order to further clarify the effect of the present invention, Examples and Comparative Examples will be described in detail, but the present invention is not limited to these Examples.

(1) Preparation of dicing tape <dicing tape (1)>
As an acrylic copolymer having a functional group, a copolymer composed of 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate and methacrylic acid having a ratio of 2-ethylhexyl acrylate of 60 mol% and a mass average molecular weight of 700,000 was prepared. .. Next, 2-isocyanatoethyl methacrylate was added so that the iodine value was 20, and an acrylic copolymer (a-) having a glass transition temperature of −50 ° C., a hydroxyl value of 10 mgKOH / g, and an acid value of 5 mgKOH / g was added. 1) was prepared.

Resin beads of an ethylene-methacrylic acid copolymer synthesized by a radical polymerization method (methacrylic acid content 13%, softening point 72 ° C., melting point 90 ° C.) were melted at 140 ° C. and used with an extruder. A base film was prepared by molding into a long film having a thickness of 100 μm.

To 100 parts by mass of the acrylic copolymer (a-1), 5 parts by mass of Coronate L (trade name, manufactured by Toso Co., Ltd.) was added as a polyisocyanate, and Ethyl KIP 150 (trade name, Lamberti) was added as a photopolymerization initiator. A mixture of 3 parts by mass (manufactured by the same company) was dissolved in ethyl acetate and stirred to prepare a pressure-sensitive adhesive composition.

The prepared pressure-sensitive adhesive layer composition is applied to a release liner made of a release-treated polyethylene-terephthalate film so that the thickness after drying is 10 μm, dried at 110 ° C. for 3 minutes, and then the above-mentioned group. A dicing tape (1) having an adhesive layer formed on the base film was prepared by laminating with a material film.

(2) Preparation of adhesive layer

(Adhesive composition b-1)
20 parts by mass of "1002" (trade name, manufactured by Mitsubishi Chemical Corporation, solid bisphenol A type epoxy resin, epoxy equivalent 600) as epoxy resin, "806" (trade name, manufactured by Mitsubishi Chemical Corporation, bisphenol F type) as epoxy resin Epoxy resin, epoxy equivalent 160, specific gravity 1.20) 55 parts by mass, 70 parts by mass of "MEH7851-4H" (trade name, manufactured by Meiwa Kasei Co., Ltd., biphenyl aralkyl type phenol resin) as a curing agent, "SO-" as a silica filler 200 parts by mass of "C2" (trade name, manufactured by Admafine Co., Ltd., average particle size 0.5 μm), and "Aerosil R972" (trade name, manufactured by Nippon Aerosil Co., Ltd., average particle size 0) as a silica filler. .016 μm) Methyl ethyl ketone was added to the composition consisting of 3 parts by mass, and the mixture was stirred and mixed to obtain a uniform composition.
In addition, 100 parts by mass of "YX6954" (trade name, manufactured by Mitsubishi Chemical Corporation, mass average molecular weight 38,000) as a phenoxy resin, and "KBM-802" (trade name, manufactured by Shinetsu Silicone Co., Ltd., Mercapto) as a coupling agent. (Propyltrimethoxysilane) 0.6 parts by mass, and "Curesol 2PHZ-PW" as a curing accelerator (trade name, manufactured by Shikoku Kasei Co., Ltd., 2-phenyl-4,5-dihydroxymethylimidazole, decomposition temperature 230 ° C.) 0.5 parts by mass was added, and the mixture was stirred and mixed until uniform. Further, this was filtered through a 100 mesh filter and vacuum defoamed to obtain a varnish of the adhesive composition b-1.

(Adhesive composition b-2)
40 parts by mass of "1002" (trade name, manufactured by Mitsubishi Chemical Co., Ltd., solid bisphenol A type epoxy resin, epoxy equivalent 600) as epoxy resin, "806" (trade name, manufactured by Mitsubishi Chemical Co., Ltd., bisphenol F type) as epoxy resin Epoxy resin, epoxy equivalent 160, specific gravity 1.20) 100 parts by mass, curing agent "Dyhard 100SF" (trade name, Degussa, dicyandiamide) 5 parts by mass, silica filler "SO-C2" (trade name, Admafine Co., Ltd.) From 350 parts by mass of company-made average particle size 0.5 μm) and 3 parts by mass of “Aerosil R972” (trade name, product name manufactured by Nippon Aerosil Co., Ltd., average primary particle size 0.016 μm) as a silica filler. Methyl ethyl ketone was added to the composition, and the mixture was stirred and mixed to obtain a uniform composition.
In addition, 100 parts by mass of "PKHH" (trade name, manufactured by INCHEM, mass average molecular weight 52,000, glass transition temperature 92 ° C.) as a phenoxy resin, and "KBM-802" (trade name, Shinetsu Silicone Co., Ltd.) as a coupling agent. 0.6 parts by mass of mercaptopropyltrimethoxysilane manufactured by the company, and "Curesol 2PHZ-PW" (trade name, manufactured by Shikoku Kasei Co., Ltd., 2-phenyl-4,5-dihydroxymethylimidazole, decomposed) as a curing accelerator. (Temperature 230 ° C.) 0.5 parts by mass was added, and the mixture was stirred and mixed until uniform. Further, this was filtered through a 100 mesh filter and vacuum defoamed to obtain a varnish of the adhesive composition b-2.

<Adhesive layer (1)>
The adhesive composition b-1 is applied to a separator made of a release-treated polyethylene-terephthalate film so that the thickness after drying is 5 μm, dried at 110 ° C. for 5 minutes, and adhered onto the separator. An adhesive film on which the agent layer was formed was produced.

<Adhesive layer (2)>
The adhesive layer (2) was obtained in the same manner as in the adhesive layer (1) except that the adhesive composition b-2 was used instead of the adhesive composition b-1.

<Adhesive layer (3)>
The adhesive layer (3) was obtained in the same manner as the adhesive layer (1) except that the coating was applied so that the thickness after drying was 20 μm.

(3) Metal layer The following metal layers were prepared.
<Metal layer (1)>
TQ-M4-VSP (trade name, manufactured by Mitsui Mining & Smelting Co., Ltd., thickness 12 μm, surface roughness RzJIS0.6um)
<Metal layer (2)>
F0-WS (trade name, manufactured by Furukawa Electric Co., Ltd., copper foil, thickness 12 μm, surface roughness RzJIS1.3um)
<Metal layer (3)>
F3-WS (trade name, manufactured by Furukawa Electric Co., Ltd., copper foil, thickness 12 μm, surface roughness RzJIS 2.8 um)
<Metal layer (4)>
DT-GLD-STD (trade name, manufactured by Furukawa Electric Co., Ltd., copper foil, thickness 18 μm, surface roughness RzJIS 9.0 um)
<Metal layer (5)>
GHY5-HA (trade name, manufactured by JX Nippon Mining & Metals Co., Ltd., thickness 18 μm, surface roughness RzJIS 0.3 μm)
<Metal layer (6)>
GTS-MP (trade name, manufactured by Furukawa Electric Co., Ltd., copper foil, thickness 35 μm, surface roughness RzJIS 11.0 μm)

(4) Fabrication of Tape for Semiconductor Processing <Example 1>
The adhesive layer (1) and the metal layer (1) obtained as described above were bonded to each other under the conditions of a bonding angle of 120 °, a pressure of 0.2 MPa, and a speed of 10 mm / s to prepare a single-sided adhesive film. The dicing tape (1) is pre-cut into a shape that can be attached to the ring frame, and the single-sided adhesive film is pre-cut into a shape that can cover the wafer. The adhesive layer of the dicing tape (1) and the metal layer of the single-sided adhesive film are formed. The sides were bonded to each other so that the adhesive layer was exposed around the single-sided adhesive film, and the tape for semiconductor processing of Example 1 was produced.

<Examples 2 to 5, Comparative Examples 1 to 2>
The semiconductor processing tapes of Examples 2 to 5 and Comparative Examples 1 and 2 were prepared by the same method as in Example 1 except that the combination of the dicing tape, the adhesive composition, and the metal layer was the combination shown in Table 1. Made.

The semiconductor processing tapes according to Examples 1 to 5 and Comparative Examples 1 and 2 were evaluated as follows. The results are shown in Table 1.

(Dicing property)
An adhesive layer of the semiconductor processing tape according to each Example and each Comparative Example was attached to the back surface of a silicon wafer having a thickness of 200 μm, dicing was performed, and the chip was divided into 7.5 mm × 7.5 mm evaluation chips. Regarding the tape for semiconductor processing with a chip after dicing, whether or not the evaluation chip with an adhesive layer is detached from the metal layer, or the adhesive layer and the evaluation chip with a metal layer are detached from the adhesive layer. Was observed. Those in which no desorption occurred were evaluated as good products, and those in which desorption occurred in even one place were evaluated as defective products.

A silicon wafer with a thickness of 650 μm was diced to 7.5 mm × 7.5 mm using a general conventional dicing die bonding film (FH-900-20 manufactured by Hitachi Chemical Co., Ltd.) to obtain an evaluation element. .. This evaluation element was die-bonded onto a silver-plated lead frame to form an evaluation substrate. The evaluation chips according to each of the Examples and Comparative Examples obtained by the method described in the above dicing property evaluation are placed on the evaluation element of the evaluation substrate under the conditions of a temperature of 160 ° C., a pressure of 0.1 MPa, and a time of 1 second. It was mounted and 20 reliable samples of the chip-on-chip structure according to each example and each comparative example were prepared.

After each reliable sample was treated with a constant temperature and humidity layer of 85 ° C./85% RH for 168 hours, the sample was passed through an IR (infrared) reflow furnace set so that the maximum temperature of the sample surface was 260 ° C. for 20 seconds. The process of cooling by leaving at room temperature was repeated three times. In each Example and each Comparative Example, the peeling of the adhesive layer and the metal layer was observed for 20 samples subjected to the above treatment, and the one in which the peeling did not occur was regarded as a non-defective product. Samples that had peeled off were marked as x as defective products. When observing the presence or absence of peeling of each sample, it was observed by a reflection method using an ultrasonic probe (Scanning Acoustic Tomography: SAT).

As shown in Table 1, the semiconductor processing tapes according to Examples 1 to 5 have a metal layer surface roughness RzJIS of 0.6 μm or more and 9.0 μm or less and 0.5 μm or more and 10.0 μm specified in the claims. Since it was less than, the dicing property and reliability were both good.

On the other hand, in the semiconductor processing tape according to Comparative Example 1, the surface roughness RzJIS of the metal layer was less than 0.5 μm, so that the dicing property and reliability were inferior. Further, the semiconductor processing tape according to Comparative Example 2 was inferior in reliability because the surface roughness RzJIS of the metal layer was 10.0 μm or more.

10: Semiconductor processing tape 11: Base film 12: Adhesive layer 13: Dicing tape 14: Metal layer 15: Adhesive layer

Claims (4)

A dicing tape having a base film and an adhesive layer,
A metal layer provided on the pressure-sensitive adhesive layer and
It is provided on the metal layer and has an adhesive layer for adhering the metal layer to the back surface of the semiconductor chip.
For semiconductor processing, the surface roughness RzJIS based on the ten-point average roughness of the surface on the adhesive layer side and the surface on the adhesive layer side of the metal layer is 0.5 μm or more and less than 10.0 μm. tape. The semiconductor processing tape according to claim 1, wherein the metal layer is a copper foil. The adhesive layer contains (A) epoxy resin, (B) curing agent, (C) phenoxy resin, and (D) surface-treated inorganic filler, and the content of (D) is the above (A). ) To 65% by weight based on the total of (D) to (D). The semiconductor processing tape according to claim 1 or 2. The pressure-sensitive adhesive layer contains an acrylic acid ester represented by CH ₂ = CHCOOR (in the formula, R is an alkyl group having 4 to 8 carbon atoms), a hydroxyl group-containing monomer, and radical reactivity in the molecule. The tape for semiconductor processing according to any one of claims 1 to 3, which contains an acrylic polymer composed of an isocyanate compound having a carbon-carbon double bond.

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