JP7333257B2 - Semiconductor back adhesion film - Google Patents

Description

The present invention relates to a semiconductor backside adhesive film. More particularly, the present invention relates to a semiconductor back adhesion film that can be used in the manufacturing process of semiconductor devices.

2. Description of the Related Art In recent years, flip-chip type semiconductor devices in which a semiconductor element such as a semiconductor chip is mounted on a substrate by flip-chip bonding are widely used. In a flip-chip type semiconductor device, a back surface protective film is sometimes used as a film for forming a protective film on the back surface of a semiconductor element in order to prevent damage to the semiconductor element (see Patent Documents 1 and 2). ).

A semiconductor element is obtained, for example, by dicing a semiconductor wafer adhered to a film (semiconductor back surface contact film) such as a back surface protective film that is used in close contact with the back surface of a semiconductor. Here, when the semiconductor wafer is attached to the film, the attachment position may be shifted, or foreign matter may enter between the adhesive surface of the semiconductor wafer and the film. If misalignment or contamination occurs, the semiconductor wafer has to be discarded, resulting in a waste of the semiconductor wafer.

Therefore, a semiconductor back adhesion film is known which has a property (reworkability) that it can be easily peeled off from a semiconductor wafer after it is once attached to the semiconductor wafer (see Patent Document 3). For example, by using a film that can be reworked by heating, if misalignment or contamination occurs between the film and the semiconductor wafer, the film can be peeled off from the semiconductor wafer by heating and aligned again. Since the semiconductor wafer can be cleaned and foreign matter can be removed, there is no need to dispose of the semiconductor wafer, and the semiconductor wafer is not wasted.

JP 2011-151360 A WO2014/092200 WO2016/158727

However, since the reworkable film disclosed in Patent Document 3 has low elasticity at normal temperature, the adhesion at normal temperature is insufficient, so the suppression of positional displacement is insufficient, and the film is wrinkled. There was a problem.

The present invention has been made in view of the above problems, and its object is to provide a semiconductor back surface adhesive film that can exhibit reworkability and is less likely to cause misalignment and film wrinkles after bonding a semiconductor wafer. That's what it is.

The inventors of the present invention have made intensive studies to achieve the above object, and found that a semiconductor back adhesion film having a maximum value of loss elastic modulus of 2° C. or higher in an uncured state can exhibit reworkability and can be used to manufacture a semiconductor wafer. It was found that misalignment and wrinkling of the film were less likely to occur after application. The present invention has been completed based on these findings.

As a first embodiment of the present invention, there is provided a semiconductor back adhesion film which is used in close contact with the back surface of a semiconductor and has a maximum value of loss elastic modulus of 2° C. or higher in an uncured state. A semiconductor back surface adhesive film having such a structure can be used in the manufacturing process of a semiconductor device.

As described above, the semiconductor back contact film according to the first embodiment of the present invention has a maximum value of loss elastic modulus of 2° C. or higher in an uncured state. The semiconductor back adhesion film having such a structure shows that the temperature at which the film denatures is relatively high when it is attached to the semiconductor wafer in an uncured state, that is, in a state in which the film is not thermoset. At the time of attachment, the adhesiveness at room temperature is relatively high, and the occurrence of misalignment and wrinkles at room temperature can be suppressed. Even so, it is possible to rework without destroying the semiconductor wafer by low-temperature heating.

It is preferable that the semiconductor back adhesion film has a denaturation point, which is the maximum value of the loss tangent, at 10° C. or higher in an uncured state. The semiconductor back adhesion film having such a structure shows that the temperature at which the film denatures is relatively high, and the adhesion at room temperature is more sufficient during the above-mentioned attachment, and misalignment and wrinkles occur at room temperature. can be further suppressed.

In the uncured state, the semiconductor back adhesion film has a first peel force of 6 N/10 mm or more in a peel test under the conditions of a temperature of 25° C. and a peel angle of 180° against silicon, and a temperature of 50° C. and a peel angle of 180° against silicon. It is preferable that the second peel force in the peel test under the condition of ° is 6 N/10 mm or less. A semiconductor back surface adhesive film having such a structure has excellent adhesion to a semiconductor wafer at room temperature, and can further suppress the occurrence of positional displacement and wrinkles at room temperature. In addition, the adhesiveness to the semiconductor wafer is relatively low near the temperature at which reworkability is exhibited, and reworkability can be easily exhibited by low-temperature heating.

It is preferable that the semiconductor back contact film has an arithmetic mean surface roughness Ra of less than 40 nm on the surface that contacts the semiconductor. When the semiconductor back adhesion film having such a structure is attached to the back surface of the semiconductor wafer, the adhesion area increases, and the adhesion of the semiconductor back adhesion film to the back surface of the semiconductor wafer at room temperature becomes more sufficient.

The semiconductor back adhesion film preferably has a storage elastic modulus of 40 MPa or more at 25° C. in an uncured state. The semiconductor back contact film having such a structure has a high elastic modulus at room temperature, moderately excellent film rigidity, and can further suppress misalignment.

The semiconductor back surface adhesive film preferably has a storage elastic modulus of 0.1 to 15 MPa at 50° C. in an uncured state. Since the semiconductor back adhesion film having such a structure has appropriate rigidity and flexibility in the vicinity of the temperature at which reworkability is exhibited, reworkability can be exhibited more easily.

The semiconductor back adhesion film preferably contains a filler, and the average particle size of the filler is 10 μm or less. The semiconductor back contact film having such a structure can easily adjust physical properties such as elastic modulus, yield point strength, and breaking elongation of the back contact film by containing a filler. When the average particle size of the filler is 10 μm or less, the total surface area of the filler in the film increases, and more bonds are formed between the surface of the filler and the resin constituting the back adhesive film. It is presumed that the brittleness is reduced and the cohesive force is increased, so that the film residue is less likely to remain on the surface of the semiconductor wafer after rework.

As a second embodiment of the present invention, a dicing tape having a laminated structure including a substrate and an adhesive layer; Provided is a dicing tape-integrated semiconductor back adhesion film comprising: The dicing tape-integrated semiconductor back adhesion film having such a structure realizes dicing for singulating a semiconductor wafer into chips on the dicing tape and good pickup of the semiconductor back adhesion film-attached chip from the dicing tape. suitable for

In the dicing tape-integrated semiconductor back adhesion film, the peel force between the adhesive layer and the semiconductor back adhesion film in an uncured state in a peel test under conditions of a temperature of 50 ° C. and a peel angle of 180 ° is 0.4 N. /100 mm or more is preferable. The dicing tape-integrated semiconductor back adhesion film having such a structure maintains optimum flexibility and self-standing at temperatures around the temperature at which reworkability is exhibited, and has high interlayer adhesion. Therefore, it is possible to prevent the film from coming off (detachment) from the dicing tape during rework and from leaving a part of the semiconductor back contact film on the wafer surface.

In the dicing tape-integrated semiconductor back contact film, it is preferable that the semiconductor back contact film is peelable at 50° C. or higher from the state of being attached to the back surface of the semiconductor wafer. The dicing tape-integrated semiconductor back contact film having such a structure has excellent reworkability when heated at a low temperature, and can be easily peeled off from the semiconductor wafer by heating to a temperature of 50° C. or higher.

The dicing tape-integrated semiconductor back contact film is preferably used by attaching the semiconductor back contact film to the back surface of the semiconductor wafer in the step of singulating the semiconductor wafer.

The semiconductor back contact film and the dicing tape-integrated semiconductor back contact film of the present invention can exhibit reworkability, and are less prone to misalignment and film wrinkles after the semiconductor wafer is attached. Therefore, when the film is attached to the back surface of the semiconductor, if misalignment or contamination with foreign matter occurs, the film can be heated and peeled off from the semiconductor wafer, and the film can be realigned or the foreign matter can be removed. There is no need to discard semiconductor wafers. Further, even after the semiconductor wafer is attached, displacement of the semiconductor wafer and wrinkling of the film are less likely to occur.

It is a schematic diagram (front cross-sectional view) showing one embodiment of a semiconductor back adhesion film. FIG. 3 is a schematic diagram (front cross-sectional view) showing another embodiment of a semiconductor back adhesion film. 1 is a schematic view (front cross-sectional view) showing an embodiment of a dicing tape-integrated semiconductor back contact film; FIG. It is the schematic (front sectional view) which shows one Embodiment of a sticking process. It is a schematic diagram (front sectional view) which shows one Embodiment of a dicing process. It is a schematic diagram (front sectional view) which shows one Embodiment of a pick-up process. It is a schematic diagram (front sectional view) which shows one Embodiment of a flip-chip mounting process.

[Semiconductor back adhesion film]
A semiconductor back contact film (sometimes simply referred to as a "back contact film") according to an embodiment of the present invention has a maximum loss elastic modulus of 2° C. or more in an uncured state. In this specification, the "front surface" of a semiconductor (workpiece) refers to the surface on which bumps for flip-chip mounting of the workpiece are formed, and the "back surface" refers to the opposite side of the surface, that is, the side on which bumps are formed. shall mean the side that is not The "back surface adhesive film" refers to a film used in close contact with the back surface of a semiconductor, and includes a film (semiconductor back surface protective film) for forming a protective film on the back surface (so-called back surface) of a semiconductor chip. Further, in this specification, the "back surface adhesive film" is a film that is in close contact with the back surface of the workpiece even after it is mounted on the semiconductor device, and is peeled off during the manufacturing process of the semiconductor device, such as a dicing tape or a separator, which will be described later. layer is not included. The back adhesion film may have a single-layer structure or a multi-layer structure.

The back adhesion film has a maximum value (maximum value) of loss elastic modulus at 2° C. or higher, preferably 5° C. or higher in an uncured state. By having the maximum value of the loss elastic modulus at 2° C. or higher, the temperature at which the film is denatured is relatively high when it is attached to a semiconductor wafer in an uncured state, that is, when the film is not thermoset. The adhesiveness at room temperature is relatively high at the time of sticking, and the occurrence of misalignment and wrinkles at room temperature can be suppressed. Even so, it is possible to rework without destroying the semiconductor wafer by low-temperature heating. The maximum value of the loss elastic modulus is, for example, 60° C. or lower, or 50° C. or lower. Further, the maximum value of the loss elastic modulus is the maximum value in the temperature range of -40°C or higher and 140°C or lower.

In the present specification, the term “uncured state” refers to a state in which the adhesive film is substantially uncured. It refers to a partially cured state. Moreover, the maximum value of the loss elastic modulus should be 2° C. or higher at least at one point in the uncured state of the back adhesion film.

The back adhesion film preferably has a storage modulus of 40 MPa or more at 25° C., more preferably 45 MPa or more in an uncured state. When the storage elastic modulus is 40 MPa or more, the elastic modulus at room temperature is high, the rigidity of the film is appropriately excellent, and misalignment can be further suppressed. The storage elastic modulus may be, for example, 5000 MPa or less and 3000 MPa or less.

The back adhesion film preferably has a storage modulus at 50° C. of 0.1 to 15 MPa, more preferably 0.15 to 9 MPa, and still more preferably 0.2 to 8 MPa in an uncured state. When the storage elastic modulus is within the above range, it has appropriate rigidity and flexibility in the vicinity of the temperature at which reworkability is exhibited, so reworkability can be exhibited more easily.

It is preferable that the back contact film has a denaturation point, which is the maximum value of loss tangent (tan δ), at 10° C. or higher in an uncured state. Having the denaturation point at 10° C. or higher indicates that the temperature at which the rear adhesive film denatures is relatively high, and the adhesion at room temperature is more sufficient, and the occurrence of misalignment and wrinkles at room temperature is further suppressed. can do. The denaturation point is preferably 50° C. or lower, more preferably 45° C. or lower. The loss tangent can be calculated from the storage modulus and loss modulus obtained by dynamic viscoelasticity measurement.

The back adhesion film may have a plurality of transformation points, which are the maximum values of the loss tangent, in an uncured state. When it has a plurality of denaturation points, it preferably has a plurality of denaturation points (in particular, all denaturation points) within the range of 10 to 80°C. If it has a plurality of denaturation points (in particular, all denaturation points) in the above temperature range, it has a denaturation point outside the above temperature range, resulting in poor adhesion at room temperature and misalignment with the work, Alternatively, difficulty in rework can be suppressed.

In an uncured state, the back adhesion film preferably has a first peel force of 6 N/10 mm or more, more preferably 7 N/10 mm or more in a peel test against silicon at a temperature of 25° C. and a peel angle of 180°. , and more preferably 8 N/10 mm or more. When the first peeling force is 6 N/10 mm or more, the adhesiveness to the semiconductor wafer is excellent near room temperature, and the occurrence of misalignment and wrinkles at room temperature can be further suppressed.

In the uncured state, the back adhesion film preferably has a second peel force of 6 N/10 mm or less, more preferably 5 N/10 mm or less in a peel test against silicon at a temperature of 50° C. and a peel angle of 180°. is. When the second peeling force is 6 N/10 mm or less, the adhesiveness to the semiconductor wafer is relatively low near the temperature at which reworkability is exhibited, and reworkability can be easily exhibited by low-temperature heating. The second peel force is, for example, 0.5 N/10 mm or more.

The first peel force and the second peel force are preferably peel forces in a peel test under the condition of a tensile speed of 300 mm/min. The first and second peel strengths can be measured using a tensile tester (trade name “Autograph AG-X”, manufactured by Shimadzu Corporation). Specifically, the preparation method and measurement method of the test piece used for the measurement are as follows.

For the measurement of the first and second peel strengths, a film having a size of 150 mm in length×10 mm in width is cut out from the back contact film as a test piece. Next, one surface of the test piece is attached to a silicon plate (mirror surface side of the unground wafer) under a temperature environment of 50°C. This bonding is performed by pressure bonding work in which a hand roller of 2 kg is reciprocated once. The film is then partially cured by heating, if desired. Then, using a tensile tester (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test under the conditions of a temperature of 25 ° C. or 50 ° C., a peel angle of 180 °, and a tensile speed of 300 mm / min. A peeling test is performed on the piece to measure the peeling force (first peeling force and second peeling force) of the back contact film to the silicon plate in the uncured state.

The back contact film preferably has an arithmetic mean surface roughness Ra of less than 40 nm on the surface that contacts the back surface of the semiconductor. When the arithmetic mean surface roughness Ra is less than 40 nm, the contact area of the back contact film when attached to the back surface of the semiconductor wafer is large, and the adhesion of the back contact film to the back surface of the semiconductor wafer at room temperature becomes more sufficient.

It is preferable that the back surface adhesion film can be peeled off at 50° C. or higher from the state of being attached to the back surface of the work. More specifically, when the back surface adhesive film is adhered to the back surface of the work, it is difficult to peel off from the back surface of the work at a temperature of less than 50°C. It is preferable that it can be peeled off easily.

The back adhesion film is formed from a resin composition. The back contact film and the composition (resin composition) forming the back contact film preferably contain a thermoplastic resin. When the back adhesion film has thermosetting properties, the back adhesion film and the resin composition may contain a thermosetting resin and a thermoplastic resin, or may react with a curing agent to form a bond. A thermoplastic resin having a curable functional group may be included. When the back adhesive film contains a thermoplastic resin having a thermosetting functional group, the resin composition does not need to contain a thermosetting resin (such as an epoxy resin).

The thermoplastic resin in the back adhesion film functions, for example, as a binder. Examples of the thermoplastic resin include acrylic resin, natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylate copolymer, polybutadiene resin. , polycarbonate resin, thermoplastic polyimide resin, polyamide resin such as 6-nylon and 6,6-nylon, phenoxy resin, acrylic resin, saturated polyester resin such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyamideimide resin , fluororesin, and the like. Only one kind of the thermoplastic resin may be used, or two or more kinds thereof may be used. As the thermoplastic resin, an acrylic resin is preferable from the viewpoint that it contains few ionic impurities and has high heat resistance.

The acrylic resin is a polymer containing structural units derived from acrylic monomers (monomer components having a (meth)acryloyl group in the molecule) as polymer structural units. The acrylic resin is preferably a polymer containing the largest proportion of structural units derived from (meth)acrylic acid ester. In addition, acrylic resin may use only 1 type, and may use 2 or more types. In the present specification, "(meth)acrylic" means "acrylic" and/or "methacrylic" (either one or both of "acrylic" and "methacrylic"), and others are the same. .

Examples of the (meth)acrylic acid esters include hydrocarbon group-containing (meth)acrylic acid esters which may have an alkoxy group. Hydrocarbon group-containing (meth)acrylic acid esters include (meth)acrylic acid alkyl esters, (meth)acrylic acid cycloalkyl esters, and (meth)acrylic acid aryl esters. Examples of the (meth)acrylic acid alkyl esters include (meth)acrylic acid methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, Isopentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester (lauryl ester), tridecyl ester, tetradecyl ester , hexadecyl ester, octadecyl ester, eicosyl ester and the like. Examples of the (meth)acrylic acid cycloalkyl esters include cyclopentyl esters and cyclohexyl esters of (meth)acrylic acid. Examples of the (meth)acrylic acid aryl esters include phenyl esters and benzyl esters of (meth)acrylic acid. Examples of the hydrocarbon group-containing (meth)acrylic acid ester having an alkoxy group include those in which one or more hydrogen atoms in the hydrocarbon group in the above hydrocarbon group-containing (meth)acrylic acid ester are substituted with an alkoxy group, Examples thereof include 2-methoxymethyl ester, 2-methoxyethyl ester and 2-methoxybutyl ester of (meth)acrylic acid. The hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group may be used alone or in combination of two or more.

The above-mentioned acrylic resin has a configuration derived from other monomer components copolymerizable with a hydrocarbon group-containing (meth) acrylic ester that may have an alkoxy group for the purpose of improving cohesive strength, heat resistance, etc. May contain units. Examples of other monomer components include carboxy group-containing monomers, acid anhydride monomers, hydroxyl group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, acrylamide, acrylonitrile, and other functional group-containing monomers. Examples include monomers. Examples of the carboxy group-containing monomers include acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Examples of the acid anhydride monomer include maleic anhydride and itaconic anhydride. Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, (4-hydroxymethylcyclohexyl)methyl (meth)acrylate and the like. Examples of the glycidyl group-containing monomer include glycidyl (meth)acrylate and methylglycidyl (meth)acrylate. Examples of the sulfonic acid group-containing monomer include styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate, (meth) ) acryloyloxynaphthalenesulfonic acid and the like. Examples of the phosphoric acid group-containing monomer include 2-hydroxyethyl acryloyl phosphate. Only one kind of the other monomer component may be used, or two or more kinds thereof may be used.

The acrylic resin that can be contained in the back adhesion film is appropriately selected from butyl acrylate, ethyl acrylate, acrylonitrile, and acrylic acid from the viewpoint of achieving both adhesion to the workpiece and good splittability during dicing of the back adhesion film. is preferably a copolymer of monomers selected for

The glass transition temperature (Tg) of the thermoplastic resin (especially acrylic resin) is preferably −35° C. or higher, more preferably −30° C. or higher. When the glass transition temperature is −35° C. or higher, it is possible to easily obtain a back contact film having a maximum loss elastic modulus of 2° C. or higher in an uncured state and a deformation point of 10° C. or higher. tend to be able to The glass transition temperature is preferably 40° C. or lower.

When the back adhesion film contains a thermosetting resin together with a thermoplastic resin, examples of the thermosetting resin include epoxy resins, phenol resins, amino resins, unsaturated polyester resins, polyurethane resins, silicone resins, and thermosetting resins. polyimide resin and the like. Only one type of the thermosetting resin may be used, or two or more types may be used. Epoxy resin is preferable as the thermosetting resin because it tends to contain less ionic impurities that may cause corrosion of the semiconductor chip. Phenol resin is preferable as a curing agent for epoxy resin.

Examples of the epoxy resin include 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 resin, and biphenyl type epoxy resin. Epoxy resins, naphthalene-type epoxy resins, fluorene-type epoxy resins, phenol novolac-type epoxy resins, cresol novolac-type epoxy resins such as ortho-cresol novolac-type epoxy resins, trishydroxyphenylmethane-type epoxy resins, tetraphenylolethane-type epoxy resins, etc. Polyfunctional epoxy resins can be mentioned. Only one type of the epoxy resin may be used, or two or more types may be used. Among them, phenol novolac type epoxy resin, ortho-cresol novolac type epoxy resin, biphenyl type epoxy resin, trishydroxyphenylmethane type epoxy resin, tetraphenylene epoxy resin, etc. A roll ethane type epoxy resin is preferred.

Phenolic resins that can act as curing agents for epoxy resins include, for example, novolac-type phenolic resins such as phenol novolac resins, phenol aralkyl resins, cresol novolac resins, tert-butylphenol novolac resins, and nonylphenol novolak resins. Examples of the phenolic resin include resol-type phenolic resins and polyoxystyrenes such as polyparaoxystyrene. Only one kind of the phenol resin may be used, or two or more kinds thereof may be used.

In the back adhesion film, from the viewpoint of sufficiently advancing the curing reaction between the epoxy resin and the phenol resin, the phenol resin preferably contains 0 hydroxyl groups per equivalent of epoxy groups in the epoxy resin component. .5 to 2.0 equivalents, more preferably 0.8 to 1.2 equivalents.

When the back adhesion film contains a thermosetting resin, the content of the thermosetting resin is 5 to 60% by mass with respect to the total mass of the back adhesion film from the viewpoint of properly curing the back adhesion film. is preferred, and more preferably 10 to 50% by mass.

When the back adhesion film contains a thermoplastic resin having a thermosetting functional group, for example, a thermosetting functional group-containing acrylic resin can be used as the thermoplastic resin. The acrylic resin in this thermosetting functional group-containing acrylic resin preferably contains a structural unit derived from a hydrocarbon group-containing (meth)acrylic acid ester as a structural unit having the largest mass ratio. Examples of the hydrocarbon group-containing (meth)acrylic acid ester include carbonized (meth)acrylic acid esters exemplified as hydrocarbon group-containing (meth)acrylic acid esters that form an acrylic resin as a thermoplastic resin that can be included in the back adhesion film. Hydrogen group-containing (meth)acrylic acid esters can be mentioned. On the other hand, examples of the thermosetting functional group in the thermosetting functional group-containing acrylic resin include glycidyl group, carboxyl group, hydroxy group, isocyanate group and the like. Among them, a glycidyl group and a carboxy group are preferable. That is, as the thermosetting functional group-containing acrylic resin, a glycidyl group-containing acrylic resin and a carboxy group-containing acrylic resin are particularly preferable. In addition, it is preferable to include a curing agent together with the thermosetting functional group-containing acrylic resin. Examples of the curing agent include the crosslinking agents that can be included in the radiation-curable adhesive for forming the adhesive layer described later. things are mentioned. When the thermosetting functional group in the thermosetting functional group-containing acrylic resin is a glycidyl group, it is preferable to use a polyphenol-based compound as the curing agent, and for example, the various phenolic resins described above can be used.

When the back adhesion film contains a thermosetting resin, it preferably contains a thermosetting catalyst (thermosetting accelerator). When the thermosetting catalyst is included, the curing reaction of the resin component can be sufficiently advanced and the curing reaction speed can be increased in curing the back adhesion film. Examples of the thermosetting catalyst include imidazole-based compounds, triphenylphosphine-based compounds, amine-based compounds, and trihalogen borane-based compounds. Examples of imidazole compounds include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl- 4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole Lithium trimellitate, 2,4-diamino-6-[2′-methylimidazolyl-(1′)]-ethyl-s-triazine, 2,4-diamino-6-[2′-undecylimidazolyl-(1 ')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6- [2′-methylimidazolyl-(1′)]-ethyl-s-triazineisocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, etc. mentioned. Examples of triphenylphosphine compounds include triphenylphosphine, tributylphosphine, tri(p-methylphenyl)phosphine, tri(nonylphenyl)phosphine, diphenyltolylphosphine, tetraphenylphosphonium bromide, methyltriphenylphosphonium, methyltriphenyl phosphonium chloride, methoxymethyltriphenylphosphonium, benzyltriphenylphosphonium chloride and the like. Triphenylphosphine-based compounds also include compounds having both a triphenylphosphine structure and a triphenylborane structure. Examples of such compounds include tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra-p-triborate, benzyltriphenylphosphonium tetraphenylborate, triphenylphosphinetriphenylborane, and the like. Examples of amine compounds include monoethanolamine trifluoroborate and dicyandiamide. Examples of trihalogen borane compounds include trichloroborane. The thermosetting catalyst may contain only one type, or may contain two or more types.

The total content ratio of the thermoplastic resin and the thermosetting resin in the back adhesion film (the content ratio of the thermoplastic resin when the thermosetting resin is not included) is, with respect to the total mass of the back adhesion film, 5 to 70% by mass is preferable, and 30 to 60% by mass is more preferable.

The back adhesion film may contain a filler (filler). By including a filler, it is easy to adjust the physical properties such as the elastic modulus of the back contact film, the strength at yield point, and the elongation at break. In addition, it suppresses irregular reflection of the light beam irradiated during laser marking, has excellent infrared shielding properties, and enables marking information to be given more clearly by laser marking. Examples of fillers include inorganic fillers and organic fillers. Constituent materials of the inorganic filler include, for example, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whisker, nitride Examples include silicon, boron nitride, crystalline silica, amorphous silica, and the like. Examples of constituent materials of the inorganic filler include single metals such as aluminum, gold, silver, copper and nickel, alloys, amorphous carbon and graphite. Examples of constituent materials of the organic filler include polymethyl methacrylate (PMMA), polyimide, polyamideimide, polyetheretherketone, polyetherimide, and polyesterimide. The above fillers may contain only one type, or may contain two or more types.

The filler may have various shapes such as spherical, needle-like, and flake-like. The average particle size of the filler is preferably 10 µm or less, more preferably 8 µm or less, and even more preferably 5 µm or less. When the average particle diameter is 10 μm or less, the total surface area of the filler in the film increases, and the brittleness of the back adhesion film is reduced by forming more bonds between the filler surface and the resin constituting the back adhesion film. Since the cohesive force is increased, film residue is less likely to remain on the surface of the semiconductor wafer after rework. In addition, it suppresses irregular reflection of the light beam irradiated during laser marking, has excellent infrared shielding properties, and enables marking information to be given more clearly by laser marking. Furthermore, the back contact film, which is to be broken into small pieces, is more excellent in splitting properties. The average particle size is, for example, 0.05 μm or more, preferably 0.1 μm or more. In the present specification, the average particle size of the filler can be determined using, for example, a photometric particle size distribution meter (trade name “LA-910”, manufactured by Horiba, Ltd.).

The content of the filler is preferably 10% by mass or more, more preferably 15% by mass or more, and more preferably 20% by mass or more, relative to the total mass of the back adhesive film. The above content is preferably 60% by mass or less, more preferably 57% by mass or less, and more preferably 55% by mass or less.

The back contact film may contain a coloring agent. The coloring agent may be a pigment or a dye. Examples of coloring agents include black coloring agents, cyan coloring agents, magenta coloring agents, and yellow coloring agents. A black coloring agent is preferable from the viewpoint of ensuring a high contrast between a laser-marked portion of the back contact film and other portions and realizing good visibility of the marked information. The coloring agent may contain only one kind, or may contain two or more kinds.

Examples of black colorants include carbon black, carbon nanotubes, graphite (graphite), copper oxide, manganese dioxide, azo pigments such as azomethine azo black, aniline black, perylene black, titanium black, cyanine black, activated carbon, and ferrite. , magnetite, chromium oxide, iron oxide, molybdenum disulfide, complex oxide-based black dyes, anthraquinone-based organic black dyes, and azo-based organic black dyes. Examples of carbon black include furnace black, channel black, acetylene black, thermal black and lamp black. As a black colorant, C.I. I. Solvent Black 3, 7, 22, 27, 29, 34, 43, 70; C.I. I. Direct Black 17, 19, 22, 32, 38, 51, 71; C.I. I. Acid Black 1, 2, 24, 26, 31, 48, 52, 107, 109, 110, 119, 154; C.I. I. Disperse Black 1, 3, 10, 24; C.I. I. Pigment Black 1 and Pigment Black 7 are also included.

Examples of cyan colorants include C.I. I. Solvent Blue 25, 36, 60, 70, 93, 95; C.I. I. Acid Blue 6, 45; C.I. I. Pigment Blue 1, 2, 3, 15, 15:1, 15:2, 15:3, 15:4, 15:5, 15:6, 16, 17, 17:1, 18, 22, 25, 56, 60, 63, 65, 66; C.I. I. Bat Blue 4; 60, C.I. I. Pigment Green 7 and the like.

Examples of magenta colorants include C.I. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 52, 58, 63, 81, 82, 83, 84, 100, 109, 111, 121, 122; C.I. I. disperse thread 9;C. I. Solvent Violet 8, 13, 14, 21, 27; C.I. I. Disperse Violet 1; C.I. I. Basic red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40; C.I. I. Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28 and the like. Examples of magenta colorants include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 42, 48: 1, 48:2, 48:3, 48:4, 49, 49:1, 50, 51, 52, 52:2, 53:1, 54, 55, 56, 57:1, 58, 60, 60:1, 63, 63:1, 63:2, 64, 64:1, 67, 68, 81, 83, 87, 88, 89, 90, 92, 101, 104, 105, 106, 108, 112, 114, 122, 123, 139, 144, 146, 147, 149, 150, 151, 163, 166, 168, 170, 171, 172, 175, 176, 177, 178, 179, 184, 185 , 187, 190, 193, 202, 206, 207, 209, 219, 222, 224, 238, 245; I. Pigment Violet 3, 9, 19, 23, 31, 32, 33, 36, 38, 43, 50; C.I. I. Bat Red 1, 2, 10, 13, 15, 23, 29, 35 and the like.

Examples of yellow colorants include C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162; I. Pigment Orange 31, 43; C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 24, 34, 35, 37, 42, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 108, 109, 110, 113, 114, 116, 117, 120, 128, 129, 133, 138, 139 , 147, 150, 151, 153, 154, 155, 156, 167, 172, 173, 180, 185, 195; I. Bat Yellow 1, 3, 20 and the like.

As the coloring agent, among others, a visible light absorbing dye is preferable. When a visible light-absorbing dye is used as the coloring agent, air bubbles are less likely to occur between the back adhesive film and the dicing tape when laser marking is performed with a dicing tape, resulting in an excellent appearance after laser marking. The visible light absorbing dye is preferably a dye having a maximum absorbance in the wavelength range of 350 to 700 nm. Examples of the visible light absorbing dye include anthraquinone dyes, perinone dyes, perylene dyes, quinoline dyes, quinacridone dyes, benzimidazolone dyes, azo dyes, isoindolinone dyes, and isoindoline dyes. , dioxazine dyes, and phthalocyanine dyes. Only one type of the visible light absorbing dye may be used, or two or more types may be used.

The content of the coloring agent is preferably 0.5% by mass or more, more preferably 1% by mass, based on the total mass of the back adhesive film, from the viewpoint of realizing the above-mentioned good visibility of the information stamped by laser marking. % or more, more preferably 2 mass % or more. The above content is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less. When the content is 10% by mass or less, air bubbles are less likely to occur between the back adhesive film and the dicing tape when laser marking is performed with the dicing tape.

The back adhesion film may contain other components as necessary. Examples of other components include flame retardants, silane coupling agents, and ion trapping agents. Examples of the flame retardant include aluminum hydroxide, magnesium hydroxide, iron hydroxide, calcium hydroxide, tin hydroxide, metal hydroxides such as composite metal hydroxides, phosphazene compounds, antimony trioxide, Examples include antimony oxide and brominated epoxy resins. Examples of the silane coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane and the like. Examples of the ion trapping agent include hydrotalcites, bismuth hydroxide, hydrous antimony oxide (eg, "IXE-300" manufactured by Toagosei Co., Ltd.), zirconium phosphate of a specific structure (eg, manufactured by Toagosei Co., Ltd.) "IXE-100"), magnesium silicate (eg "Kyoward 600" manufactured by Kyowa Chemical Industry Co., Ltd.), aluminum silicate (eg "Kyoward 700" manufactured by Kyowa Chemical Industry Co., Ltd.), and the like. Compounds that can form complexes with metal ions can also be used as ion trapping agents. Examples of such compounds include triazole-based compounds, tetrazole-based compounds, and bipyridyl-based compounds. Among these, triazole compounds are preferred from the viewpoint of the stability of the complex formed with metal ions. Examples of such triazole compounds include 1,2,3-benzotriazole, 1-{N,N-bis(2-ethylhexyl)aminomethyl}benzotriazole, carboxybenzotriazole, 2-(2-hydroxy- 5-methylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-t-butylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3-t-butyl-5-methylphenyl )-5-chlorobenzotriazole, 2-(2-hydroxy-3,5-di-t-amylphenyl)benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)benzotriazole, 6-(2 -benzotriazolyl)-4-t-octyl-6'-t-butyl-4'-methyl-2,2'-methylenebisphenol, 1-(2',3'-hydroxypropyl)benzotriazole, 1- (1,2-dicarboxydiethyl)benzotriazole, 1-(2-ethylhexylaminomethyl)benzotriazole, 2,4-di-t-pentyl-6-{(H-benzotriazol-1-yl)methyl}phenol , 2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole, 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy, octyl -3-[3-t-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate, 2-ethylhexyl-3-[3-t-butyl-4-hydroxy -5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-( 1,1,3,3-tetramethylbutyl)phenol, 2-(2H-benzotriazol-2-yl)-4-t-butylphenol, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2- (2-hydroxy-5-t-octylphenyl)-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3, 5-di-t-amylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-t-butylphenyl)-5-chloro-benzotriazole, 2-[2-hydroxy-3,5-di (1,1-dimethylbenzyl)phenyl]-2H-benzotriazole, 2,2′-methylenebis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl ) phenol], 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, methyl-3-[3-(2H-benzotriazol-2-yl)- 5-t-butyl-4-hydroxyphenyl]propionate and the like. Specific hydroxyl group-containing compounds such as quinol compounds, hydroxyanthraquinone compounds, and polyphenol compounds can also be used as ion trapping agents. Specific examples of such hydroxyl group-containing compounds include 1,2-benzenediol, alizarin, anthralphine, tannin, gallic acid, methyl gallate, and pyrogallol. Only one kind of the other components may be used, or two or more kinds thereof may be used.

When the back adhesion film has a multi-layer structure, it has a laminated structure including an adhesive layer having a surface to be adhered to the back surface of the work and a laser mark layer capable of imparting stamped information by laser marking. may The adhesive layer may have thermosetting properties so that it can be adhered to the back surface of the work and protected by heat curing after being attached to the back surface of the work. If the adhesive layer is non-thermosetting, the adhesive layer adheres to and protects the back surface of the work by adhesion (wettability) at the interface due to pressure sensitivity or chemical bonding. Is possible. The surface of the laser mark layer is subjected to laser marking during the manufacturing process of the semiconductor device. The back adhesive film having such a laminated structure has a laminated structure in which the adhesive layer is heat-cured by heat treatment at 120° C. for 2 hours, while the laser mark layer is not substantially heat-cured. can take In addition, in the back adhesion film, the layer which is not substantially thermoset by heat treatment at 120° C. for 2 hours includes an already cured thermosetting layer. Each of the adhesive layer and the laser mark layer may have a single layer structure or a multilayer structure.

The laser mark layer is preferably a thermosetting layer (a thermoset layer) in which the thermosetting component is thermoset at the time of laser marking. The thermoset laser mark layer is formed by curing a thermosetting resin composition layer formed from a resin composition forming the laser mark layer.

When the back contact film has a multilayer structure having an adhesive layer and a laser marking layer, the ratio of the thickness of the laser marking layer to the thickness of the adhesive layer is preferably 1 or more, more preferably 1.5 or more. , more preferably 2 or more. The above ratio is, for example, 10 or less.

The thickness of the back adhesion film is, for example, 2 to 200 μm, preferably 4 to 160 μm, more preferably 6 to 100 μm, still more preferably 10 to 80 μm. When the thickness is 2 μm or more, the back surface of the work can be more strongly protected. When the thickness is 200 μm or less, the workpiece after the back contact can be made thinner.

FIG. 1 shows an embodiment in which the back adhesion film has a multilayer structure. As shown in FIG. 1 , the back contact film 10 is placed on the separator 30 . The back contact film 10 has a multi-layer structure including an adhesive layer 11 and a laser mark layer 12, and the laser mark layer 12 is adhered to the separator 30 in a detachable manner. In FIG. 1, the adhesive layer 11 and the laser mark layer 12 may have a reverse positional relationship (that is, the adhesive layer 11 is releasably adhered to the separator 30). When the adhesive layer 11 and the laser mark layer 12 have the positional relationship shown in FIG. 1, the back adhesion film 10 can be adhered to the back surface of the work and heat-cured for use. On the other hand, when the positional relationship between the adhesive layer 11 and the laser mark layer 12 is opposite to that shown in FIG. 1, it can be preferably used for producing a dicing tape-integrated back adhesion film described later.

FIG. 2 shows an embodiment in which the back adhesion film has a single-layer structure. As shown in FIG. 2 , the back contact film 10 is placed on the separator 30 . The back adhesion film 10 can be adhered to the back surface of the work and heat-cured for use.

[Dicing tape-integrated semiconductor back adhesion film]
The back adhesive film has a form comprising a dicing tape having a laminated structure including a substrate and an adhesive layer, and a back adhesive film peelably adhered to the adhesive layer of the dicing tape, that is, It may be used as a dicing tape-integrated semiconductor back adhesion film (sometimes referred to as "dicing tape-integrated back adhesion film"). The dicing tape-integrated semiconductor back contact film is suitable for dicing a semiconductor wafer on a dicing tape to separate chips and for picking up chips with a semiconductor back contact film from the dicing tape.

The dicing tape-integrated semiconductor back adhesion film has a peel force of 0.4 N / in a peel test under the conditions of a temperature of 50 ° C. and a peel angle of 180 ° between the adhesive layer and the back adhesion film in an uncured state. It is preferably 100 mm or more, more preferably 0.5 N/100 mm or more. When the dicing tape-integrated semiconductor back adhesion film having such a configuration has a peeling force of 0.4 N/100 mm or more, the back adhesion film has optimum flexibility and self-standing near the temperature at which reworkability is exhibited. and has high interlayer adhesion, it is possible to prevent the film from coming off (detachment) from the dicing tape during rework and from leaving part of the back adhesion film on the wafer surface.

The peel force is not particularly limited, but is preferably the peel force in a peel test under conditions of a peel angle of 180° and a tensile speed of 300 mm/min. The peel force can be measured using a peel tester (trade name “Autograph AGS-J”, manufactured by Shimadzu Corporation).

In the dicing tape-integrated semiconductor back contact film, it is preferable that the back contact film can be peeled off at 50° C. or higher from the state of being attached to the semiconductor wafer. The dicing tape-integrated semiconductor back contact film having such a structure has excellent reworkability when heated at a low temperature, and can be easily peeled off from the semiconductor wafer by heating to a temperature of 50° C. or higher.

The dicing tape-integrated semiconductor back contact film is preferably used by attaching the semiconductor back contact film to the back surface of the semiconductor wafer in the step of singulating the semiconductor wafer. A detailed usage method will be described later.

One embodiment of the dicing tape-integrated back contact film will be described with reference to FIG. The dicing tape-integrated back contact film 1 shown in FIG. 3 uses the back contact film 10 shown in FIG. The dicing tape-integrated back adhesion film 1 can be used in the process of obtaining a semiconductor chip accompanied by a chip-equivalent size film for forming a semiconductor chip back adhesion film. It has a laminated structure including

(Base material)
The base material in the dicing tape is an element that functions as a support in the dicing tape or the dicing tape-integrated back adhesive film. Substrates include, for example, plastic substrates (especially plastic films). The base material may be a single layer or a laminate of the same or different base materials.

Examples of the resin constituting the plastic substrate include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymerized polypropylene, block copolymerized polypropylene, and homopolypropylene. , polybutene, polymethylpentene, ethylene-vinyl acetate copolymer (EVA), ionomer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester (random, alternating) copolymer, ethylene- Polyolefin resins such as butene copolymers and ethylene-hexene copolymers; polyurethanes; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate, and polybutylene terephthalate (PBT); polycarbonates; polyimides; polyamide such as aramid and wholly aromatic polyamide; polyphenyl sulfide; fluorine resin; polyvinyl chloride; polyvinylidene chloride; cellulose resin; Good heat shrinkability is secured in the base material, and in the expansion process for widening the separation distance between semiconductor chips after dicing, it is easy to maintain the chip separation distance using a dicing tape or partial heat shrinkage of the base material. From a viewpoint, the substrate preferably contains an ethylene-vinyl acetate copolymer or polyvinyl chloride as a main component. In addition, let the main component of a base material be a component which occupies the largest mass ratio in a structural component. Only one kind of the above resin may be used, or two or more kinds thereof may be used. When the pressure-sensitive adhesive layer is a radiation-curable pressure-sensitive adhesive layer as described later, the substrate preferably has radiation transparency.

When the substrate is a plastic film, the plastic film may be non-oriented, or may be oriented in at least one direction (uniaxial direction, biaxial direction, etc.). When oriented in at least one direction, the plastic film is heat shrinkable in at least one direction. In order for the substrate and the dicing tape to have isotropic heat shrinkability, the substrate is preferably a biaxially oriented film. The plastic film oriented in at least one direction can be obtained by stretching an unstretched plastic film in at least one direction (uniaxial stretching, biaxial stretching, etc.). The base material and the dicing tape preferably have a thermal shrinkage rate of 1 to 30%, more preferably 2 to 25%, and more preferably 2 to 25% in a heat treatment test performed at a heating temperature of 100 ° C. and a heating time of 60 seconds. It is preferably 3 to 20%, particularly preferably 5 to 20%. It is preferable that the thermal shrinkage rate is the thermal shrinkage rate in at least one of the MD direction and the TD direction.

The surface of the adhesive layer side of the base material may be subjected to corona discharge treatment, plasma treatment, sand mat processing, ozone exposure treatment, flame exposure treatment, high voltage shock treatment, etc. for the purpose of enhancing adhesion and retention with the adhesive layer. Physical treatments such as exposure treatment and ionizing radiation treatment; chemical treatments such as chromic acid treatment; and surface treatments such as easy-adhesion treatment with a coating agent (undercoating agent). Moreover, in order to impart antistatic properties, a conductive deposition layer containing metals, alloys, oxides thereof, or the like may be provided on the substrate surface. The surface treatment for enhancing adhesion is preferably applied to the entire surface of the adhesive layer side of the substrate.

The thickness of the substrate is preferably 40 μm or more, more preferably 50 μm or more, and even more preferably 50 μm or more, from the viewpoint of ensuring strength for the substrate to function as a support in the dicing tape and the dicing tape-integrated back adhesive film. is at least 55 μm, particularly preferably at least 60 μm. From the viewpoint of achieving appropriate flexibility in the dicing tape and the dicing tape-integrated back adhesion film, the thickness of the substrate is preferably 200 μm or less, more preferably 180 μm or less, and still more preferably 150 μm or less. be.

(Adhesive layer)
The adhesive layer in the dicing tape is an adhesive layer that can intentionally reduce the adhesive force (adhesive force reduction type adhesive layer) by external action during the use process of the dicing tape integrated back adhesive film. It may be a pressure-sensitive adhesive layer (adhesive force non-reducing pressure-sensitive adhesive layer) whose adhesive force is hardly or not reduced by an external action in the process of using the dicing tape-integrated back adhesive film, The dicing tape-integrated back contact film can be appropriately selected according to the method and conditions for singulating the workpiece to be singulated using the back contact film. The pressure-sensitive adhesive layer may have a single layer structure or a multilayer structure.

When the adhesive layer is an adhesive layer that can reduce adhesive strength, the adhesive layer exhibits relatively high adhesive strength and relatively low adhesive strength during the manufacturing process and use process of the dicing tape integrated back adhesive film. It is possible to use properly the state indicating the force. For example, when bonding the back adhesive film to the adhesive layer of the dicing tape in the manufacturing process of the dicing tape integrated back adhesive film, or when the dicing tape integrated back adhesive film is used in the dicing process, the adhesive layer While it is possible to suppress or prevent the back adhesion film from floating from the adhesive layer by utilizing the state of exhibiting a relatively high adhesive strength, after that, the semiconductor chip is removed from the dicing tape of the back adhesion film integrated with the dicing tape. In the pick-up process for picking up, the pick-up can be easily performed by reducing the adhesive strength of the adhesive layer.

Examples of the adhesive that forms such an adhesive force-reducing adhesive layer include a radiation-curable adhesive and a heat-foaming adhesive. As the adhesive for forming the adhesive force-reducing adhesive layer, one kind of adhesive may be used, or two or more kinds of adhesives may be used.

As the radiation-curable adhesive, for example, an adhesive that is cured by irradiation with electron beams, ultraviolet rays, α-rays, β-rays, γ-rays, or X-rays can be used. Adhesives (ultraviolet curable adhesives) can be particularly preferably used.

As the radiation-curable adhesive, for example, an additive containing a base polymer such as an acrylic polymer and a radiation-polymerizable monomer component or oligomer component having a functional group such as a radiation-polymerizable carbon-carbon double bond type radiation curable adhesives.

The above acrylic polymer is a polymer containing a structural unit derived from an acrylic monomer (a monomer component having a (meth)acryloyl group in the molecule) as a structural unit of the polymer. The acrylic polymer is preferably a polymer containing the largest proportion of structural units derived from (meth)acrylic acid ester. In addition, acrylic polymer may use only 1 type, and may use 2 or more types.

Examples of the (meth)acrylic acid esters include hydrocarbon group-containing (meth)acrylic acid esters which may have an alkoxy group. As the hydrocarbon group-containing (meth)acrylic acid ester optionally having an alkoxy group, the hydrocarbons optionally having an alkoxy group exemplified as the structural units of the acrylic resin that the back adhesion film may contain. Group-containing (meth)acrylic acid esters may be mentioned. The hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group may be used alone or in combination of two or more. As the hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group, 2-ethylhexyl acrylate and lauryl acrylate are preferable. In order to appropriately exhibit basic properties such as adhesiveness due to the hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group in the adhesive layer, all monomer components for forming the acrylic polymer , the ratio of the hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group is preferably 40% by mass or more, more preferably 60% by mass or more.

The acrylic polymer is derived from other monomer components that can be copolymerized with the hydrocarbon group-containing (meth)acrylic acid ester that may have an alkoxy group for the purpose of improving cohesive strength, heat resistance, etc. It may contain a structural unit that Examples of the above-mentioned other monomer components include other monomers exemplified as structural units of the acrylic resin that can be contained in the above-mentioned back adhesion film. Only one kind of the other monomer component may be used, or two or more kinds thereof may be used. In order to appropriately exhibit basic properties such as adhesiveness due to the hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group in the adhesive layer, all monomer components for forming the acrylic polymer , the total ratio of the other monomer components is preferably 60% by mass or less, more preferably 40% by mass or less.

The acrylic polymer may contain a structural unit derived from a polyfunctional monomer copolymerizable with the monomer component forming the acrylic polymer in order to form a crosslinked structure in the polymer skeleton. Examples of the polyfunctional monomer include hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, penta Erythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy (meth)acrylate (e.g. polyglycidyl (meth)acrylate), polyester Examples thereof include monomers having (meth)acryloyl groups and other reactive functional groups in the molecule such as (meth)acrylates and urethane (meth)acrylates. Only one kind of the polyfunctional monomer may be used, or two or more kinds thereof may be used. In order to appropriately exhibit basic properties such as adhesiveness due to the hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group in the adhesive layer, all monomer components for forming the acrylic polymer is preferably 40% by mass or less, more preferably 30% by mass or less.

Acrylic polymers are obtained by subjecting one or more monomer components including acrylic monomers to polymerization. Polymerization methods include solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization.

The acrylic polymer can be obtained by polymerizing raw material monomers for forming it. Polymerization techniques include, for example, solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization. The mass average molecular weight of the acrylic polymer is preferably 100,000 or more, more preferably 200,000 to 3,000,000. When the weight average molecular weight is 100,000 or more, the amount of low-molecular-weight substances in the pressure-sensitive adhesive layer tends to be small, and contamination of the back adhesive film, semiconductor wafer, and the like can be further suppressed.

The pressure-sensitive adhesive layer or the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer may contain a cross-linking agent. For example, when an acrylic polymer is used as the base polymer, the acrylic polymer can be crosslinked to further reduce low-molecular-weight substances in the pressure-sensitive adhesive layer. Also, the mass average molecular weight of the acrylic polymer can be increased. Examples of the cross-linking agent include polyisocyanate compounds, epoxy compounds, polyol compounds (such as polyphenol compounds), aziridine compounds, and melamine compounds. When a cross-linking agent is used, the amount used is preferably about 5 parts by mass or less, more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the base polymer.

Examples of the radiation-polymerizable monomer component include urethane (meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta ( meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate and the like. Examples of the radiation-polymerizable oligomer component include various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based oligomers, and those having a molecular weight of about 100 to 30,000 are preferred. The content of the radiation-polymerizable monomer component and oligomer component in the radiation-curable adhesive that forms the adhesive layer is, for example, 5 to 500 parts by mass, preferably 40 to 150 parts by mass, with respect to 100 parts by mass of the base polymer. It is about a part by mass. Further, as the additive-type radiation-curable pressure-sensitive adhesive, for example, one disclosed in JP-A-60-196956 may be used.

As the radiation-curable pressure-sensitive adhesive, an internal radiation-curable adhesive containing a base polymer having a radiation-polymerizable carbon-carbon double bond or other functional group in the polymer side chain, in the polymer main chain, or at the polymer main chain end. Also included are adhesives. The use of such an internal radiation-curable adhesive tends to suppress unintended changes in adhesive properties over time due to migration of low-molecular-weight components within the formed adhesive layer.

An acrylic polymer is preferable as the base polymer contained in the internal radiation-curable pressure-sensitive adhesive. As a method for introducing a radiation-polymerizable carbon-carbon double bond into an acrylic polymer, for example, an acrylic polymer is obtained by polymerizing (copolymerizing) raw material monomers containing a monomer component having a first functional group. After that, a compound having a second functional group capable of reacting with the first functional group and a radiation polymerizable carbon-carbon double bond is added to an acrylic polymer while maintaining the radiation polymerizability of the carbon-carbon double bond. and condensation reaction or addition reaction method.

Combinations of the first functional group and the second functional group include, for example, a carboxy group and an epoxy group, an epoxy group and a carboxy group, a carboxy group and an aziridyl group, an aziridyl group and a carboxy group, a hydroxy group and an isocyanate group, An isocyanate group, a hydroxy group, and the like are included. Among these, a combination of a hydroxy group and an isocyanate group, and a combination of an isocyanate group and a hydroxy group are preferred from the viewpoint of ease of reaction tracking. Among them, it is technically difficult to produce a polymer having a highly reactive isocyanate group, and on the other hand, from the viewpoint of ease of production and availability of an acrylic polymer having a hydroxy group, the first functional group is A preferred combination is a hydroxy group and the second functional group is an isocyanate group. Compounds having an isocyanate group and a radiation-polymerizable carbon-carbon double bond, that is, radiation-polymerizable unsaturated functional group-containing isocyanate compounds include, for example, methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, m-isopropenyl- α,α-dimethylbenzyl isocyanate and the like. Further, as the acrylic polymer having a hydroxy group, those containing structural units derived from the above-mentioned hydroxy group-containing monomers and ether compounds such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether. is mentioned.

The radiation-curable adhesive preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include α-ketol compounds, acetophenone compounds, benzoin ether compounds, ketal compounds, aromatic sulfonyl chloride compounds, photoactive oxime compounds, benzophenone compounds, thioxanthone compounds, Camphorquinone, halogenated ketone, acylphosphinate, acylphosphonate and the like. Examples of the α-ketol compounds include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, 2-methyl-2-hydroxy propiophenone, 1-hydroxycyclohexylphenyl ketone, and the like. Examples of the acetophenone compounds include methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)-phenyl]-2 -morpholinopropan-1-one and the like. Examples of the benzoin ether compounds include benzoin ethyl ether, benzoin isopropyl ether, and anisoin methyl ether. Examples of the ketal compound include benzyl dimethyl ketal. Examples of the aromatic sulfonyl chloride compounds include 2-naphthalenesulfonyl chloride. Examples of the photoactive oxime compound include 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime. Examples of the benzophenone-based compounds include benzophenone, benzoylbenzoic acid, and 3,3'-dimethyl-4-methoxybenzophenone. Examples of the thioxanthone compounds include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropyl. thioxanthone and the like. The content of the photopolymerization initiator in the radiation-curable adhesive is, for example, 0.05 to 20 parts by weight with respect to 100 parts by weight of the base polymer.

The heat-expandable pressure-sensitive adhesive is a pressure-sensitive adhesive containing a component (foaming agent, heat-expandable microspheres, etc.) that foams or expands when heated. Examples of the foaming agent include various inorganic foaming agents and organic foaming agents. Examples of the inorganic foaming agent include ammonium carbonate, ammonium hydrogencarbonate, sodium hydrogencarbonate, ammonium nitrite, sodium borohydride, and azides. Examples of the organic foaming agent include alkane hydrochlorides such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate; and paratoluene. Hydrazine compounds such as sulfonyl hydrazide, diphenylsulfone-3,3'-disulfonyl hydrazide, 4,4'-oxybis(benzenesulfonylhydrazide), allylbis(sulfonylhydrazide); p-toluylenesulfonyl semicarbazide, 4,4'- Semicarbazide compounds such as oxybis (benzenesulfonyl semicarbazide); triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; N,N'-dinitrosopentamethylenetetramine, N,N'-dimethyl- Examples include N-nitroso compounds such as N,N'-dinitrosoterephthalamide. Examples of the heat-expandable microspheres include microspheres having a structure in which a substance that easily gasifies and expands upon heating is encapsulated in the shell. Examples of substances that easily gasify and expand when heated include isobutane, propane, and pentane. Thermally expandable microspheres can be produced by encapsulating a substance that is easily gasified and expanded by heating in a shell-forming substance by a coacervation method, an interfacial polymerization method, or the like. As the shell-forming substance, a substance exhibiting thermal melting properties and a substance capable of bursting due to the action of thermal expansion of the enclosed substance can be used. Examples of such substances include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, polysulfone, and the like.

Examples of the non-reducing adhesive layer include a pressure-sensitive adhesive layer. In the pressure-sensitive adhesive layer, an adhesive layer formed from the radiation-curable adhesive described above with respect to the adhesive force-reducing adhesive layer is cured by irradiation in advance and has a certain adhesive force. An adhesive layer is included. As the adhesive that forms the non-adhesion-reducing adhesive layer, one kind of adhesive may be used, or two or more kinds of adhesives may be used. Further, the entire adhesive layer may be a non-adhesive force-reducing adhesive layer, or a part thereof may be a non-adhesive force-reducing adhesive layer. For example, when the adhesive layer has a single-layer structure, the entire adhesive layer may be a non-adhesive force-reducing adhesive layer, or a specific portion of the adhesive layer (for example, a dicing frame to be attached) A region outside the central region) is a non-adhesive force-reducing adhesive layer, and other portions (for example, a central region that is a semiconductor wafer divided body or a semiconductor wafer adhesion target region) It may be a pressure-sensitive adhesive layer capable of reducing the pressure-sensitive adhesive force. Further, when the adhesive layer has a laminated structure, all the adhesive layers in the laminated structure may be non-adhesive pressure-reducing adhesive layers, or some of the adhesive layers in the laminated structure may have non-adhesive strength. It may be a reduced pressure-sensitive adhesive layer.

The pressure-sensitive adhesive layer (irradiated radiation-curable pressure-sensitive adhesive layer) formed by pre-curing the pressure-sensitive adhesive layer (radiation-unexposed radiation-curable pressure-sensitive adhesive layer) formed from a radiation-curable pressure-sensitive adhesive by irradiation with radiation Even if the adhesive strength is reduced by irradiation, it exhibits adhesiveness due to the contained polymer component, and can exhibit the minimum adhesive strength required for the adhesive layer of the dicing tape in the dicing process. When a radiation-cured pressure-sensitive adhesive layer that has been exposed to radiation is used, the entire pressure-sensitive adhesive layer may be the irradiated radiation-curing pressure-sensitive adhesive layer in the surface spreading direction of the pressure-sensitive adhesive layer, and a part of the pressure-sensitive adhesive layer may be It may be a radiation-curable pressure-sensitive adhesive layer that has been exposed to radiation, and the other portion may be a radiation-curable pressure-sensitive adhesive layer that has not been exposed to radiation. In this specification, the term "radiation-curable pressure-sensitive adhesive layer" refers to a pressure-sensitive adhesive layer formed from a radiation-curable pressure-sensitive adhesive. It includes both the radiation-cured radiation-curable pressure-sensitive adhesive layer after the agent layer has been cured by irradiation.

As the pressure-sensitive adhesive for forming the pressure-sensitive pressure-sensitive adhesive layer, a known or commonly used pressure-sensitive pressure-sensitive adhesive can be used, and an acrylic pressure-sensitive adhesive or a rubber-based pressure-sensitive adhesive having an acrylic polymer as a base polymer is preferably used. can be done. When the pressure-sensitive adhesive layer contains an acrylic polymer as a pressure-sensitive adhesive, the acrylic polymer is preferably a polymer containing the structural unit derived from (meth)acrylic acid ester as the largest structural unit in terms of mass ratio. preferable. As the acrylic polymer, for example, the acrylic polymer described as the acrylic polymer that can be included in the additive-type radiation-curable pressure-sensitive adhesive can be employed.

The pressure-sensitive adhesive layer or the pressure-sensitive adhesive that forms the pressure-sensitive adhesive layer includes, in addition to the components described above, known or commonly used pressure-sensitive adhesive layers such as cross-linking accelerators, tackifiers, anti-aging agents, and colorants (pigments, dyes, etc.). Additives used in may be blended. Examples of the coloring agent include compounds that are colored by exposure to radiation. When a compound that is colored by irradiation is contained, only the irradiated portion can be colored. The compound that is colored by exposure to radiation is a compound that is colorless or light-colored before exposure to radiation and becomes colored by exposure to radiation, and examples thereof include leuco dyes. The amount of the compound that is colored by exposure to radiation is not particularly limited and can be appropriately selected.

The thickness of the pressure-sensitive adhesive layer is not particularly limited. From the viewpoint of balancing, it is preferably about 1 to 50 μm, more preferably 2 to 30 μm, and still more preferably 3 to 25 μm.

The back contact film and the dicing tape-integrated back contact film may have a separator on the back contact film surface. Specifically, each back contact film or each dicing tape-integrated back contact film may be in the form of a sheet having a separator, or the separator may be in a long shape and a plurality of back contact films may be placed thereon. A film or a plurality of dicing tape-integrated back adhesion films may be disposed, and the separator may be wound to form a roll. The separator is an element for covering and protecting the surface of the back contact film, and is peeled off from the sheet when using the back contact film or the back contact film integrated with the dicing tape. Examples of separators include polyethylene terephthalate (PET) film, polyethylene film, polypropylene film, plastic films and papers surface-coated with a release agent such as a fluorine-based release agent or a long-chain alkyl acrylate release agent.

The thickness of the separator is, for example, 10-200 μm, preferably 15-150 μm, more preferably 20-100 μm. When the thickness is 10 μm or more, the separator is less likely to break due to cuts during processing of the separator. When the thickness is 200 μm or less, the dicing tape-integrated back contact film can be easily peeled off from the separator when it is attached to the substrate and the frame.

[Method for producing back adhesion film]
The back contact film 10, which is one embodiment of the present invention, is manufactured, for example, as follows.

For the back contact film 10 shown in FIG. 1, first, the adhesive layer 11 and the laser mark layer 12 are separately produced. The adhesive layer 11 is formed by applying a resin composition (adhesive composition) for forming the adhesive layer 11 on the separator to form a resin composition layer, and then removing the solvent and curing by heating. It can be made by solidifying the material layer. In producing the adhesive layer 11, the heating temperature is, for example, 90 to 150° C., and the heating time is, for example, 1 to 2 minutes. Examples of methods for applying the resin composition include roll coating, screen coating, and gravure coating. On the other hand, the laser mark layer 12 is formed by coating a resin composition for forming the laser mark layer 12 on a separator to form a resin composition layer, and then removing the solvent and curing by heating to solidify the resin composition layer. It can be made by In producing the laser mark layer 12, the heating temperature is, for example, 90 to 160° C., and the heating time is, for example, 2 to 4 minutes. The adhesive layer 11 and the laser mark layer 12 can be made in a form each with a separator. Then, the exposed surfaces of the adhesive layer 11 and the laser mark layer 12 are adhered to each other, and punching is performed so as to obtain the desired planar projected shape and planar projected area, thereby forming the adhesive layer 11 and the laser mark layer 12 . A back contact film 10 having a laminated structure of

[Manufacturing method of dicing tape-integrated back adhesion film]
The dicing tape-integrated back contact film 1, which is one embodiment of the present invention, is manufactured, for example, as follows.

The dicing tape 20 of the dicing tape-integrated back adhesive film 1 shown in FIG. 3 can be produced by providing an adhesive layer 22 on a prepared base material 21 . For example, the base material 21 made of resin can be obtained by forming a film by a known or commonly used 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 co-extrusion method, a dry lamination method, and the like. The substrate 21 is subjected to surface treatment as necessary. In forming the adhesive layer 22, for example, after preparing an adhesive composition for forming an adhesive layer, first, the composition is applied on the substrate 21 or a separator to form an adhesive composition layer. do. Examples of methods for applying the pressure-sensitive adhesive composition include roll coating, screen coating, gravure coating, and the like. Next, the pressure-sensitive adhesive composition layer is heated to remove the solvent, if necessary, and to cause a cross-linking reaction, if necessary. The heating temperature is, for example, 80 to 150° C., and the heating time is, for example, 0.5 to 5 minutes. When the pressure-sensitive adhesive layer 22 is formed on the separator, the pressure-sensitive adhesive layer 22 with the separator is attached to the base material 21, and then the desired planar projection shape (for example, a shape similar to the back adhesive film 10) is formed. shape) and planar projected area, and then the separator is peeled off. As a result, the dicing tape 20 having a laminated structure of the substrate 21 and the adhesive layer 22 is produced.

Next, the laser mark layer 12 side of the rear adhesion film 10 obtained above is adhered to the adhesive layer 22 side of the dicing tape 20 . The bonding temperature is, for example, 10 to 50° C., and the bonding pressure (linear pressure) is, for example, 0.1 to 20 kgf/cm. When the pressure-sensitive adhesive layer 22 is the radiation-curable pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer 22 may be irradiated with radiation such as ultraviolet rays before the bonding, or the substrate 21 may be exposed after the bonding. The pressure-sensitive adhesive layer 22 may be irradiated with radiation such as ultraviolet rays from the side. Alternatively, such radiation irradiation may not be performed in the manufacturing process of the dicing tape-integrated back adhesive film 1 (in this case, the adhesive layer 22 is cured by radiation during the use process of the dicing tape-integrated back adhesive film 1. Is possible). When the adhesive layer 22 is of an ultraviolet curing type, the amount of ultraviolet irradiation for curing the adhesive layer 22 is, for example, 50 to 500 mJ/cm ² . In the dicing tape-integrated back adhesive film 1, the area (irradiated area R) where irradiation is performed as a measure to reduce the adhesive force of the adhesive layer 22 is, for example, as shown in FIG. This is the area within the mating area excluding its periphery.

As described above, for example, the back contact film 10 shown in FIG. 1 and the dicing tape-integrated back contact film 1 shown in FIG. 3 can be produced.

[Method for manufacturing a semiconductor device]
A semiconductor device can be manufactured using the dicing tape-integrated back contact film. Specifically, the step of attaching the back surface of the workpiece to the back adhesive film side (especially the adhesive layer side) of the back adhesive film integrated with the dicing tape (attaching step), and the individualization by cutting the target including at least the workpiece. A semiconductor device can be manufactured by a manufacturing method including a step of obtaining a diced semiconductor chip (dicing step). 4 to 7 show steps in a method of manufacturing a semiconductor device using the dicing tape-integrated back contact film 1 shown in FIG.

(Affixing process)
In the pasting step, the work to be pasted on the back adhesion film side (especially the adhesive layer side) of the dicing tape integrated back adhesion film may be a semiconductor wafer or a plurality of semiconductor chips whose back and/or side surfaces are sealed with resin. Examples include a closed sealing body and the like. Then, for example, as shown in FIG. 4A, the semiconductor wafer 40 held by the wafer processing tape T1 is attached to the back adhesive film 10 (in particular, the adhesive layer 11) of the dicing tape-integrated back adhesive film 1. and paste them together. The surface of the semiconductor wafer 40 is provided with bumps (not shown) for flip-chip mounting. Thereafter, as shown in FIG. 4B, the wafer processing tape T1 is peeled off from the semiconductor wafer 40. Next, as shown in FIG.

(Thermal curing process)
When the back adhesion film or the adhesive layer in the film is thermosetting, it is preferable to include a step of thermally curing the back adhesion film (thermosetting step) after the sticking step. For example, in the thermosetting step, heat treatment is performed to thermoset the adhesive layer 11 . The heating temperature is preferably 80 to 200°C, more preferably 100 to 150°C. The heating time is preferably 0.5 to 5 hours, more preferably 1 to 3 hours. Specifically, the heat treatment is performed at 120° C. for 2 hours, for example. In the heat curing step, the heat curing of the adhesive layer 11 enhances the adhesion between the back contact film 10 of the dicing tape integrated back contact film 1 and the semiconductor wafer 40, and the dicing tape integrated back contact film 1 and the back contact film are formed. 10 to the semiconductor wafer fixed holding force is increased. In addition, if the back adhesion film does not have thermosetting properties, it may be baked at, for example, a temperature range of 50 to 100° C. for several hours. power increases.

(Laser marking process)
It is preferable that the above method for manufacturing a semiconductor device includes a step of performing laser marking (laser marking step) by irradiating the back adhesive film with a laser from the substrate side of the dicing tape. When the heat curing process is performed, the laser marking process is preferably performed after the heat curing process. Specifically, in the laser marking process, for example, laser marking is performed by irradiating the laser mark layer 12 with a laser from the base material 21 side of the dicing tape 20 . By this laser marking process, various information such as character information and graphic information can be marked on each semiconductor chip. In the laser marking process, it is possible to collectively and efficiently perform laser marking on a plurality of semiconductor chips in one laser marking process. Examples of lasers used in the laser marking process include gas lasers and solid-state lasers. Examples of gas lasers include carbon dioxide lasers (CO ₂ lasers) and excimer lasers. Examples of solid-state lasers include Nd:YAG lasers.

(Dicing process)
In the dicing step, for example, as shown in FIG. 5, a frame (dicing frame) 51 for pressing and fixing the dicing tape onto the adhesive layer 22 of the dicing tape-integrated back adhesive film 1 is attached to hold the dicing machine. After being held by the tool 52, cutting is performed by a dicing blade provided in the dicing machine. In FIG. 5, the cut portion is schematically represented by a thick line. In the dicing process, the semiconductor wafer is separated into semiconductor chips 41, and the back contact film 10 of the dicing tape-integrated back contact film 1 is cut into small pieces 10'. As a result, the semiconductor chip 41 with the film 10', that is, the semiconductor chip 41 with the film 10' is obtained.

(Radiation irradiation step)
The method for manufacturing a semiconductor device may include a step of irradiating the pressure-sensitive adhesive layer with radiation from the substrate side (radiation irradiation step). When the pressure-sensitive adhesive layer of the dicing tape is a layer formed of a radiation-curable pressure-sensitive adhesive, instead of the above-described radiation irradiation in the manufacturing process of the dicing tape-integrated back adhesive film, after the above-described dicing step, The pressure-sensitive adhesive layer may be irradiated with radiation such as ultraviolet rays from the substrate side. The irradiation dose is, for example, 50 to 500 mJ/cm ² . In the dicing tape-integrated back adhesive film, the area where irradiation is performed as a measure to reduce the adhesive force of the adhesive layer (irradiated area R shown in FIG. 3) is, for example, the peripheral edge in the back adhesive film bonding area of the adhesive layer. This is the area excluding the part.

(Pickup process)
The method for manufacturing a semiconductor device preferably includes a step of picking up the film-attached semiconductor chip (pick-up step). The pick-up step includes, for example, a cleaning step of washing the semiconductor chip 41 side of the dicing tape 20 with the semiconductor chip 41 with the film 10′ using a washing liquid such as water, and a separation distance between the semiconductor chips 41 with the film 10′. An expansion step for spreading may be performed after passing through as necessary. For example, as shown in FIG. 6, the semiconductor chip 41 with the film 10 ′ is picked up from the dicing tape 20 . For example, in a state in which the dicing tape 20 with the dicing frame 51 is held by the holder 52 of the device, the pin member 53 of the pick-up mechanism is attached to the semiconductor chip 41 with the film 10' to be picked up on the lower side of the dicing tape 20 in the drawing. is raised and pushed up through the dicing tape 20, and then sucked and held by a suction jig 54. - 特許庁In the pick-up process, the pushing speed of the pin member 53 is, for example, 1 to 100 mm/sec, and the pushing amount of the pin member 53 is, for example, 50 to 3000 μm.

(Flip chip mounting process)
It is preferable that the method for manufacturing the semiconductor device described above includes a step of flip-chip mounting the film-attached semiconductor chip 41 (flip-chip step) after the pick-up step. For example, as shown in FIG. 7, a semiconductor chip 41 with a film 10' is flip-chip mounted on a mounting board 61. FIG. Examples of the mounting board 61 include a lead frame, a TAB (Tape Automated Bonding) film, and a wiring board. The semiconductor chip 41 is electrically connected to the mounting board 61 via the bumps 62 by flip chip mounting. Specifically, the substrate (electrode pad) (not shown) that the semiconductor chip 41 has on the circuit forming surface side and the terminal portion (not shown) that the mounting substrate 61 has are electrically connected via the bumps 62 . be. The bumps 62 are, for example, solder bumps. A thermosetting underfill agent 63 is interposed between the chip 41 and the mounting board 61 .

As described above, a semiconductor device can be manufactured using the dicing tape-integrated back contact film.

EXAMPLES The present invention will be described in more detail with reference to Examples below, but the present invention is not limited to these Examples.

Comparative example 1
(Semiconductor back adhesion film)
90 parts by mass of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”, glass transition temperature: −37° C., manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name “JER YL980”, Mitsubishi Chemical Corporation Company) 40 parts by mass, epoxy resin E ₂ (trade name “KI-3000-4”, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) 60 parts by mass, and phenol resin (trade name “MEH7851-SS”, Meiwa Kasei Co., Ltd. manufactured by Admatechs) 100 parts by mass, silica filler S ₁ (trade name “SO-25R”, average particle size: 0.5 μm, manufactured by Admatechs Co., Ltd.) 220 parts by mass, and visible light absorbing black dye (trade name “OIL BLACK BS", manufactured by Orient Chemical Industry Co., Ltd.) 5 parts by mass and 1 part by mass of a thermosetting catalyst (trade name "Curesol 2PHZ" manufactured by Shikoku Kasei Kogyo Co., Ltd.) are added to methyl ethyl ketone and mixed, and the solid content concentration is A resin composition of 36% by mass was obtained. Next, an applicator was used to apply the resin composition onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, and a 25 μm-thick semiconductor back adhesion film (thermosetting semiconductor back adhesion film) was produced on a PET separator.

(Dicing tape integrated semiconductor back adhesion film)
The semiconductor back adhesive film obtained above was attached to the pressure-sensitive adhesive layer of a dicing tape (peeling force at a peeling angle of 180° to a SUS plate: 0.8 N/10 mm). A hand roller was used for the lamination. Next, 300 mJ of ultraviolet rays were irradiated from the dicing tape side to prepare a dicing tape-integrated semiconductor back adhesion film.

Example 1
In place of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”), acrylic resin A ₂ (trade name “Teisan Resin SG-280EK23”, glass transition temperature: -29°C, manufactured by Nagase ChemteX Corporation) was used. A back contact film and a dicing tape-integrated semiconductor back contact film were produced in the same manner as in Comparative Example 1, except that they were used.

Example 2
In place of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”), acrylic resin A ₃ (trade name “Teisan Resin SG-70L”, glass transition temperature: -13°C, manufactured by Nagase ChemteX Corporation) was used. A back contact film and a dicing tape-integrated semiconductor back contact film were produced in the same manner as in Comparative Example 1, except that a thermosetting catalyst was not added.

Example 3
In place of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”), acrylic resin A ₃ (trade name “Teisan Resin SG-70L”, glass transition temperature: -13°C, manufactured by Nagase ChemteX Corporation) was used. A back contact film and a dicing tape-integrated semiconductor back contact film were produced in the same manner as in Comparative Example 1, except that they were used.

Example 4
In place of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”), acrylic resin A ₄ (trade name “Teisan Resin SG-708-6”, glass transition temperature: 4 ° C., manufactured by Nagase ChemteX Corporation) A back contact film and a dicing tape-integrated semiconductor back contact film were produced in the same manner as in Comparative Example 1, except for using .

Comparative example 2
(Preparation of laser mark layer)
90 parts by mass of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”, glass transition temperature: −37° C., manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name “JER YL980”, Mitsubishi Chemical Corporation Company) 40 parts by mass, epoxy resin E ₂ (trade name “KI-3000-4”, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) 60 parts by mass, and phenol resin (trade name “MEH7851-SS”, Meiwa Kasei Co., Ltd. manufactured by Admatechs) 100 parts by mass, silica filler S ₁ (trade name “SO-25R”, average particle size: 0.5 μm, manufactured by Admatechs Co., Ltd.) 220 parts by mass, and visible light absorbing black dye (trade name “OIL BLACK BS", manufactured by Orient Chemical Industry Co., Ltd.) 5 parts by mass and 10 parts by mass of a thermosetting catalyst (trade name "Curesol 2PHZ" manufactured by Shikoku Kasei Kogyo Co., Ltd.) are added to methyl ethyl ketone and mixed, and the solid content concentration is A resin composition of 36% by mass was obtained. Next, an applicator was used to apply the resin composition onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, and a 17 μm-thick laser mark layer (thermally cured layer) was produced on the PET separator.

(Preparation of adhesive layer)
90 parts by mass of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”, glass transition temperature: −37° C., manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name “JER YL980”, Mitsubishi Chemical Corporation Company) 40 parts by mass, epoxy resin E ₂ (trade name “KI-3000-4”, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) 60 parts by mass, and phenol resin (trade name “MEH7851-SS”, Meiwa Kasei Co., Ltd. manufactured by Admatechs) 100 parts by mass, silica filler S ₁ (trade name “SO-25R”, average particle size: 0.5 μm, manufactured by Admatechs Co., Ltd.) 220 parts by mass, and visible light absorbing black dye (trade name “OIL BLACK BS", manufactured by Orient Chemical Industry Co., Ltd.) and 5 parts by mass were added to methyl ethyl ketone and mixed to obtain a resin composition having a solid content concentration of 36% by mass. Next, an applicator was used to apply the resin composition onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, and an adhesive layer having a thickness of 8 μm was formed on the PET separator.

(Semiconductor back adhesion film)
The laser mark layer on the PET separator prepared as described above and the adhesive layer on the PET separator were laminated using a laminator. Specifically, the exposed surfaces of the laser mark layer and the adhesive layer were bonded together under conditions of a temperature of 100° C. and a pressure of 0.6 MPa. A back adhesion film was produced as described above.

(Dicing tape integrated semiconductor back adhesion film)
A dicing tape-integrated semiconductor back adhesion film was produced in the same manner as in Comparative Example 1 except that the semiconductor back adhesion film obtained above was used.

Example 5
(Preparation of laser mark layer)
In place of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”), acrylic resin A ₃ (trade name “Teisan Resin SG-70L”, glass transition temperature: -13°C, manufactured by Nagase ChemteX Corporation) was used. A laser mark layer (heat-cured layer) was produced in the same manner as in Comparative Example 2 except that it was used.

(Preparation of adhesive layer)
In place of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”), acrylic resin A ₃ (trade name “Teisan Resin SG-70L”, glass transition temperature: -13°C, manufactured by Nagase ChemteX Corporation) was used. An adhesive layer was prepared in the same manner as in Comparative Example 2 except that the adhesive layer was used.

(Semiconductor back adhesion film)
The laser mark layer on the PET separator prepared as described above and the adhesive layer on the PET separator were laminated using a laminator. Specifically, the exposed surfaces of the laser mark layer and the adhesive layer were bonded together under conditions of a temperature of 100° C. and a pressure of 0.6 MPa. A back adhesion film was produced as described above.

(Dicing tape integrated semiconductor back adhesion film)
A dicing tape-integrated semiconductor back adhesion film was produced in the same manner as in Comparative Example 1 except that the semiconductor back adhesion film obtained above was used.

Example 6
(Preparation of adhesive layer)
90 parts by mass of acrylic resin A ₃ (trade name “Teisan Resin SG-70L”, glass transition temperature: −13° C., manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name “JER YL980”, Mitsubishi Chemical Corporation Company) 40 parts by mass, epoxy resin E ₂ (trade name “KI-3000-4”, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) 60 parts by mass, and phenol resin (trade name “MEH7851-SS”, Meiwa Kasei Co., Ltd. ), 220 parts by mass of silica filler S ₂ (trade name “FB-105FD”, average particle size: 11 μm, manufactured by Denka Co., Ltd.), and visible light absorbing black dye (trade name “OIL BLACK BS” , manufactured by Orient Chemical Industry Co., Ltd.) was added to methyl ethyl ketone and mixed to obtain a resin composition having a solid content concentration of 36% by mass. Next, an applicator was used to apply the resin composition onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, and an adhesive layer having a thickness of 8 μm was formed on the PET separator.

(Semiconductor back adhesion film)
The laser mark layer on the PET separator prepared in Example 5 and the adhesive layer on the PET separator prepared as described above were laminated using a laminator. Specifically, the exposed surfaces of the laser mark layer and the adhesive layer were bonded together under conditions of a temperature of 100° C. and a pressure of 0.6 MPa. A back adhesion film was produced as described above.

(Dicing tape integrated semiconductor back adhesion film)
A dicing tape-integrated semiconductor back adhesion film was produced in the same manner as in Comparative Example 1 except that the semiconductor back adhesion film obtained above was used.

Example 7
Instead of acrylic resin A ₁ (trade name “Teisan Resin SG-600TEA”), acrylic resin A ₅ (trade name “Teisan Resin SG-P3”, glass transition temperature: 12 ° C., manufactured by Nagase ChemteX Corporation was used. A back contact film and a dicing tape-integrated semiconductor back contact film were produced in the same manner as in Comparative Example 1 except for the above.

<Evaluation>
The back adhesion films and the dicing tape-integrated back adhesion films obtained in Examples and Comparative Examples were evaluated as follows. Table 1 shows the results.

(1) Misalignment property The back contact films obtained in the examples and comparative examples were heated at 80°C for 1 minute on a silicon wafer (mirror surface side of the unground wafer) and attached, and then naturally cooled for 10 minutes. . The bonding surface of the two-layer back contact film is the adhesive layer side. After that, a 2 kg roller with a double-sided adhesive tape (trade name “No. 500”, manufactured by Nitto Denko Corporation) pasted on the surface of the roll was reciprocated a plurality of times for 30 seconds on the back adhesion film. At that time, the case where at least one of wrinkling, floating, or peeling occurred in the back contact film due to positional deviation of the back contact film was evaluated as x, and the case where none of them occurred was evaluated as ○.

(2) Reworkability The back contact films obtained in the Examples and Comparative Examples were heated at 80°C for 1 minute to adhere to a silicon wafer (mirror surface side of an unground wafer), and then naturally cooled for 10 minutes. The bonding surface of the two-layer back contact film is the adhesive layer side. Then, after heating on a hot plate at 50 ° C. for 1 minute, an adhesive tape (trade name "BT-315", manufactured by Nitto Denko Co., Ltd.) is pasted on the back adhesion film, and the back adhesion film is peeled off (back adhesion peeling of the interface between the film and the silicon wafer) was attempted. At that time, the case where the back adhesion film could be easily peeled off was evaluated as ◯, the case where the film could be peeled off but some film residue was generated on the silicon wafer was evaluated as Δ, and the case where it could not be peeled off was evaluated as x.

(3) Dynamic Viscoelasticity Measurement The back contact films obtained in Examples and Comparative Examples were laminated to a total thickness of 200 μm, and cut into a width of 10 mm to prepare a test piece. For the above test piece, using a dynamic viscoelasticity measuring device (trade name "RSA3", manufactured by TA Instruments), the temperature was raised at a temperature increase rate of 10 ° C./min in the temperature range from -40 ° C. to 100 ° C., Storage modulus and loss modulus were measured. Then, the storage modulus at 25° C., the storage modulus at 50° C., and the maximum value temperature of the loss modulus were calculated. The temperature at which the loss tangent (tan δ) calculated from the storage elastic modulus and the loss elastic modulus is 0.5 or more was taken as the denaturation point. In addition, when two or more maximum values of the loss tangent (tan δ) calculated from the storage elastic modulus and the loss elastic modulus are 0.5 or more, the temperature of the maximum value of tan δ calculated on the lowest temperature side is the first The temperature of the maximum value of tan δ calculated at the denaturation point and the highest temperature side was calculated as the second denaturation point.

(4) Arithmetic Mean Surface Roughness The arithmetic mean surface roughness Ra was measured by two-dimensional analysis using a surface roughness profiler (manufactured by Zygo) for the back contact film surfaces obtained in Examples and Comparative Examples. did. The measurement surface of the two-layer back contact film is the adhesive layer side.

(5) Silicon peeling force A silicon wafer (dummy wafer (mirror surface side) manufactured by Tokyo Kako Co., Ltd.) was placed on a hot plate, and an adhesive tape (trade name “BT-315”, Nitto Denko Co., Ltd.), the back surface adhesion films obtained in Examples and Comparative Examples having a length of 150 mm and a width of 10 mm were laminated together by reciprocating a 2 kg roller once. Then, after standing for 1 minute on a hot plate set at 80 ° C., leave at room temperature (about 23 ° C.) for 20 minutes, and after standing, peel tester (trade name “Autograph AGS-J”, stock (manufactured by Shimadzu Corporation), under a predetermined temperature condition (25 ° C. or 50 ° C.), peeling angle: 180 °, tensile speed: 300 mm / min, peel off the back adhesion film with the back reinforcement. (Peel off at the interface between the back adhesion film and the silicon wafer), measure the maximum load (the maximum value of the load excluding the peak top at the beginning of measurement) when peeled off, and measure this maximum load. It was determined as the peeling force (N/10 mm width) of the film to silicon.

(6) Peeling force between adhesive layer and back adhesive film (interlayer peeling force)
Adhesive tape (trade name “BT-315”, manufactured by Nitto Denko Corporation) is attached to the surface of the back adhesion film, and the dicing tape integrated back adhesion obtained in Examples and Comparative Examples with a length of 150 mm and a width of 100 mm. Using a peeling tester (trade name “Autograph AGS-J”, manufactured by Shimadzu Corporation), the film is applied to the surface under the conditions of temperature: 50 ° C., peeling angle: 180 °, tensile speed: 300 mm / min. The back adhesive film to which the adhesive tape is attached is peeled off (peeled off at the interface between the back adhesive film and the adhesive layer on the dicing tape), and the average load of the load when this is peeled off (30 mm at the beginning of measurement and measurement The average value of the load excluding 30 mm at the end was measured, and this average load was obtained as the peeling force (N/100 mm width) between the pressure-sensitive adhesive layer and the back adhesive film.

1 dicing tape integrated back adhesive film 10 back adhesive film 11 adhesive layer 12 laser mark layer 20 dicing tape 21 base material 22 adhesive layer 30 separator 40 semiconductor wafer 41 semiconductor chip

Claims (10)

A film used in close contact with the back surface of a semiconductor, in an uncured state ,
having a maximum value of loss elastic modulus at 2° C. or higher,
The first peel force in a peel test under the conditions of a temperature of 25 ° C. and a peel angle of 180 ° against silicon is 6 N / 10 mm or more,
A semiconductor back adhesive film having a second peel force of 6 N/10 mm or less in a peel test against silicon at a temperature of 50° C. and a peel angle of 180°. 2. The semiconductor back adhesive film according to claim 1, which has a denaturation point, which is a maximum value of loss tangent, at 10[deg.] C. or higher in an uncured state. 3. The semiconductor back contact film according to claim 1, wherein the arithmetic mean surface roughness Ra of the surface in contact with the semiconductor is less than 40 nm. 4. The semiconductor back contact film according to claim 1, which has a storage elastic modulus of 40 MPa or more at 25° C. in an uncured state. The semiconductor back contact film according to any one of claims 1 to 4 , which has a storage elastic modulus of 0.1 to 15 MPa at 50°C in an uncured state. The semiconductor back contact film according to any one of claims 1 to 5 , which contains a filler and has an average particle size of 10 µm or less. a dicing tape having a laminated structure including a substrate and an adhesive layer;
A semiconductor back adhesive film integrated with a dicing tape, comprising the semiconductor back adhesive film according to any one of claims 1 to 6 , which is peelably adhered to the adhesive layer of the dicing tape. 8. The method according to claim 7 , wherein a peel force between the adhesive layer and the semiconductor back adhesive film in an uncured state in a peel test under conditions of a temperature of 50° C. and a peel angle of 180° is 0.4 N/100 mm or more. dicing tape integrated semiconductor back adhesion film. 9. The dicing tape-integrated semiconductor back adhesion film according to claim 7 , wherein said semiconductor back adhesion film can be peeled off at 50[deg.] C. or higher from the state of being attached to the back surface of the semiconductor wafer. The dicing tape-integrated semiconductor back-surface adhesion according to any one of claims 7 to 9 , wherein the semiconductor back-surface adhesion film is attached to the back surface of the semiconductor wafer in the step of singulating the semiconductor wafer. film.

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