JP6921644B2 - Backside protective film with integrated dicing tape - Google Patents

Description

The present invention relates to a dicing tape integrated back surface protective film that can be used in the manufacturing process of a semiconductor device.

In the manufacture of a semiconductor device including a semiconductor chip mounted on a flip chip, a film for forming a protective film on the so-called back surface of the chip (back surface protective film) may be used. Such a back surface protective film may be provided in a form integrated with the dicing tape.

The conventional dicing tape integrated back surface protective film includes, for example, a dicing tape having a laminated structure including a base material and an adhesive layer, and a thermosetting back surface protective film that is releasably adhered to the adhesive layer. Have. Such a dicing tape integrated back surface protective film is used, for example, as follows. First, the back surface protective film surface of the dicing tape integrated back surface protective film is attached to the semiconductor wafer which is the work. Next, in order to increase the adhesion of the back surface protective film to the wafer, the back surface protective film is thermoset by heating (cure step). Next, while the wafer is held on the back surface protective film integrated with the dicing tape, blade dicing for individualizing the wafer into chips is performed (dicing step). In the dicing step, the wafer and the back surface protective film that is in close contact with the wafer are cut by the dicing blade along the planned cutting line on the wafer. As a result, on the dicing tape, the wafer is cut and individualized into chips, and the back surface protective film is cut into film small pieces having a size equivalent to the chips. That is, the chip obtained through the dicing step takes a form accompanied by a film for forming a protective film on the back surface thereof. Next, after passing through the cleaning step, the chip with the film is picked up from the dicing tape (pickup step). At this time, it is necessary that the film in the chip with film to be picked up is appropriately peeled from the adhesive layer of the dicing tape. The conventional dicing tape integrated back surface protective film is used as described above, for example. Techniques related to such a dicing tape-integrated back surface protective film are described in, for example, Patent Documents 1 and 2 below.

Japanese Unexamined Patent Publication No. 2011-151360 International Publication No. 2014/092200

Regarding the above-mentioned dicing process, cracks may occur in the region on the back surface protective film side of the wafer to be cut by the dicing blade, and the lower the adhesion or fixing holding force of the back surface protective film to the wafer, the more such. It is known that cracks are likely to occur. The back surface protective film has insufficient force to fix and hold the wafer due to minute chips (chipping) and minute cracks formed on the cut surface of the wafer, that is, the side surface of the chip due to the impact and friction during cutting by the dicing blade. In some cases, it is thought that it will grow into a crack. Therefore, in the process of using the conventional dicing tape-integrated back surface protective film, as described above, a curing step for increasing the adhesion of the back surface protective film to the wafer is required.

However, in the above-mentioned curing step, the back surface protective film is thermally cured, so that the adhesion of the film to the wafer is increased, but the adhesion of the back surface protective film to the dicing tape or its adhesive layer is also increased. Such an increase in adhesive force may hinder the peeling of the film of the film-attached chip from the dicing tape adhesive layer in the pick-up process after the curing step, and therefore hinder the pick-up of the film-attached chip. There is.

The present invention has been conceived under the above circumstances, and an object of the present invention is to cause cracks on the side surface of a chip in blade dicing for individualizing a wafer into a chip on a dicing tape. It is an object of the present invention to provide a dicing tape integrated back surface protective film suitable for realizing good pick-up of a chip with a back surface protective film from a dicing tape.

According to the present invention, a dicing tape integrated back surface protective film is provided. This dicing tape integrated back surface protective film includes a dicing tape and a back surface protective film. The dicing tape has a laminated structure including a base material and an adhesive layer. The back surface protective film has a laminated structure including a laser mark layer for forming a marking target surface and an adhesive layer for forming a work sticking surface, and is used as an adhesive layer for dicing tape on the laser mark layer side. It is in close contact so that it can be peeled off. When the back surface protective film was heat-treated at 120 ° C. for 2 hours, the back surface protective film sample piece having a width of 10 mm was measured under the conditions of an initial chuck distance of 22.5 mm, a frequency of 1 Hz, and a heating rate of 10 ° C./min. The tensile storage elastic modulus at 80 ° C. is 0.5 GPa or more, preferably 0.75 GPa or more, and more preferably 1 GPa or more. The thickness of the back surface protective film sample piece is, for example, 25 μm. At the same time, in a peeling test under the conditions of 23 ° C., a peeling angle of 180 ° and a tensile speed of 300 mm / min, the distance between the back surface protective film and the adhesive layer of the dicing tape is 0.1 N / 20 mm or less, preferably 0. It can exhibit an adhesive force of 08 N / 20 mm or less, more preferably 0.06 N / 20 mm or less. The dicing tape-integrated back surface protective film having such a configuration can be used to obtain a semiconductor chip with a film for forming a chip back surface protective film in the manufacturing process of the semiconductor device.

As described above, the back surface protective film in the dicing tape integrated back surface protective film is laminated including a laser mark layer that is in close contact with the adhesive layer of the dicing tape and an adhesive layer for forming a work attachment surface. Has a structure. That is, in the back surface protective film of the dicing tape integrated back surface protective film, the layer that adheres to the dicing tape and the layer that forms the work sticking surface are different. In such a back surface protective film, the adhesive layer for forming the work-attached surface is thermoset by heat treatment at 120 ° C. for 2 hours, while the laser mark layer that adheres to the dicing tape is substantially heat. It is suitable for adopting a laminated structure that does not cure. The layer of the back surface protective film that is not substantially thermoset by heat treatment at 120 ° C. for 2 hours includes a thermosetting layer that has already been cured.

As described above, the back surface protective film in this dicing tape integrated back surface protective film has an initial chuck distance of 22.5 mm and a frequency of 1 Hz for a back surface protective film sample piece having a width of 10 mm when heat-treated at 120 ° C. for 2 hours. The tensile storage elastic modulus at 80 ° C. measured under the condition of a heating rate of 10 ° C./min is 0.5 GPa or more, preferably 0.75 GPa or more, and more preferably 1 GPa or more. Such a configuration is suitable for securing the holding force for fixing to the wafer required in the dicing process in the back surface protective film integrated with the dicing tape. The back surface protective film is heat-treated at 120 ° C. for 2 hours to obtain a relatively high tensile storage elastic modulus as described above. The back surface protective film surface of the dicing tape integrated back surface protective film is attached to a semiconductor wafer. It is suitable for heat-curing the back surface protective film after the combination to realize a high fixing holding force against the wafer. This dicing tape integrated back surface protective film having the structure suitable for securing the holding force for fixing to the wafer required in the dicing process is provided on the side surface of the chip in blade dicing for individualizing the wafer into a chip on the dicing tape. Suitable for suppressing the formation of cracks. Then, the adhesive layer is thermoset by the configuration suitable for securing the fixing holding force to the wafer required in the dicing process and the heat treatment at 120 ° C. for 2 hours, while the laser mark layer is substantially thermoset. This dicing tape integrated back surface protective film, which also has the above-mentioned configuration suitable for adopting a laminated structure that does not, is heat-treated to the wafer while suppressing an increase in the adhesive force against the dicing tape for the back surface protective film. Suitable for securing a fixed holding force. The configuration that suppresses the increase in the adhesive force against the dicing tape during the heat treatment for ensuring the fixing holding force against the wafer in the back surface protective film contributes to appropriately picking up the chip with the back surface protective film from the dicing tape in the pick-up process.

As described above, the distance between the back surface protective film (the back surface protective film before the heat treatment) in the back surface protective film integrated with the dicing tape and the adhesive layer of the dicing tape is 23 ° C., the peeling angle is 180 °, and the tensile speed is 300 mm. In the peeling test under the condition of / minute, the adhesive strength can be 0.1 N / 20 mm or less, preferably 0.8 N / 20 mm or less, and more preferably 0.6 N / 20 mm or less. When the pressure-sensitive adhesive layer of the dicing tape is a curable pressure-sensitive adhesive layer containing a radiation-curable pressure-sensitive adhesive, the adhesive strength between the back surface protective film and the cured pressure-sensitive adhesive layer takes these values. The back surface protective film integrated with the dicing tape is constructed. The structure relating to such low adhesive strength between the back surface protective film and the dicing tape adhesive layer and the heat treatment at 120 ° C. for 2 hours heat-cures the adhesive layer while substantially forming the laser mark layer. This dicing tape-integrated back surface protective film, which also has the above-mentioned configuration suitable for adopting a laminated structure that does not cure by heat, is used for heat treatment for ensuring the fixing holding force against the wafer for the back surface protective film. It is suitable for realizing good pick-up of a chip with a back surface protective film from the dicing tape in the pick-up process after suppressing an increase in the adhesive force of the dicing tape.

As described above, the back surface protective film integrated with the dicing tape of the present invention suppresses cracks on the side surface of the chip during blade dicing for individualizing the wafer into chips on the dicing tape, and also suppresses cracks from the dicing tape. It is suitable for realizing a good pickup of a chip with a back surface protective film.

In the back surface protective film integrated with the dicing tape, preferably, the laser mark layer is a cured thermosetting layer, and the adhesive layer has thermosetting property. That is, it is preferable that the laser mark layer is a cured thermosetting layer and the adhesive layer is an uncured thermosetting layer. In such a configuration, the adhesive layer for forming the work-attached surface is thermoset by heat treatment at 120 ° C. for 2 hours, while the laser mark layer in close contact with the dicing tape is not substantially thermoset. It is suitable for realizing the laminated structure of the back surface protective film.

The back surface protective film of the back surface protective film integrated with the dicing tape has a calorific value in the range of 50 to 200 ° C., more preferably 40 J / g or less, in the differential scanning calorimetry at a temperature rise rate of 10 ° C./min. Is 35 J / g or less, more preferably 30 J / g or less. In such a configuration, when the laser mark layer of the back surface protective film is a cured thermosetting layer and the adhesive layer is an uncured thermosetting layer, for example, the back surface protective film is fixed to the wafer. It is suitable for suppressing an increase in the adhesive force against the dicing tape during the heat treatment for ensuring the holding power, and therefore contributes to the realization of good pick-up of the chip with the back surface protective film in the pick-up process.

In the back surface protective film integrated with the dicing tape, the value of the ratio of the thickness of the laser mark layer to the thickness of the adhesive layer is preferably 1 or more, more preferably 1.5 or more, and more preferably 2 or more. When the laser mark layer of the back surface protective film is a cured thermosetting layer and the adhesive layer is a thermosetting layer in an uncured state, for example, the cured laser mark layer in the entire thickness of the back surface protective film. The larger the ratio of the thickness of the blade, the more the blade dicing tends to suppress the occurrence of cracks on the side surface of the chip.

It is sectional drawing of the back surface protective film integrated with dicing tape which concerns on one Embodiment of this invention. A part of the steps in the semiconductor device manufacturing method in which the dicing tape integrated back surface protective film shown in FIG. 1 is used is shown. A part of the steps in the semiconductor device manufacturing method in which the dicing tape integrated back surface protective film shown in FIG. 1 is used is shown. A part of the steps in the semiconductor device manufacturing method in which the dicing tape integrated back surface protective film shown in FIG. 1 is used is shown. A part of the steps in the semiconductor device manufacturing method in which the dicing tape integrated back surface protective film shown in FIG. 1 is used is shown. A part of the steps in the semiconductor device manufacturing method in which the dicing tape integrated back surface protective film shown in FIG. 1 is used is shown.

FIG. 1 is a schematic cross-sectional view of a back surface protective film X integrated with a dicing tape according to an embodiment of the present invention. The dicing tape integrated back surface protective film X can be used in the process of obtaining a semiconductor chip accompanied by a film having a size equivalent to that of the chip for forming the back surface protective film of the semiconductor chip, and the film 10 and the dicing tape 20 are combined. It has a laminated structure including. The film 10 is a back surface protective film that is bonded to the circuit non-forming surface, that is, the back surface of the semiconductor wafer that is the work. The dicing tape 20 has a laminated structure including a base material 21 and an adhesive layer 22. The pressure-sensitive adhesive layer 22 has a pressure-sensitive adhesive surface 22a on the film 10 side. The film 10 is releasably adhered to the pressure-sensitive adhesive layer 22 or the pressure-sensitive adhesive surface 22a thereof. Further, the back surface protective film X integrated with the dicing tape has a disk shape having a size corresponding to the semiconductor wafer as the work.

The film 10 which is a back surface protective film has a laminated structure including a laser mark layer 11 and an adhesive layer 12. The laser mark layer 11 is located on the dicing tape 20 side of the film 10 and is in close contact with the dicing tape 20 or its adhesive layer 22. The surface of the laser mark layer 11 on the dicing tape 20 side is laser-marked during the manufacturing process of the semiconductor device. Further, in the present embodiment, the laser mark layer 11 is a thermosetting layer containing a thermosetting component and is already in a thermosetting state. The adhesive layer 12 is a thermosetting layer that is located on the side of the film 10 on which the workpieces are bonded and is in an uncured state in the present embodiment.

The laser mark layer 11 in the film 10 may have a composition containing a thermosetting resin and a thermoplastic resin as a resin component, or is accompanied by a thermosetting functional group capable of reacting with a curing agent to form a bond. It may have a composition containing a thermoplastic resin.

When the laser mark layer 11 has a composition containing a thermosetting resin and a thermoplastic resin, the thermosetting resin includes, for example, an epoxy resin, a phenol resin, an amino resin, an unsaturated polyester resin, a polyurethane resin, and a silicone resin. , And thermosetting polyimide resin. The laser mark layer 11 may contain one kind of thermosetting resin, or may contain two or more kinds of thermosetting resins. Since the epoxy resin tends to have a small content of ionic impurities and the like that can cause corrosion of the semiconductor chip to be protected by the back surface protective film formed from the film 10 as described later, the laser mark of the film 10 tends to be small. It is preferable as the thermosetting resin in the layer 11. Further, as a curing agent for exhibiting thermosetting property in the epoxy resin, a phenol resin is preferable.

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. Bifunctional epoxy resins such as resins, naphthalene type epoxy resins, fluorene type epoxy resins, phenol novolac type epoxy resins, orthocresol novolac type epoxy resins, trishydroxyphenylmethane type epoxy resins, and tetraphenylol ethane type epoxy resins and polyfunctionality. Epoxy resin can be mentioned. Examples of the epoxy resin include a hydantoin type epoxy resin, a trisglycidyl isocyanurate type epoxy resin, and a glycidylamine type epoxy resin. Further, the laser mark layer 11 may contain one kind of epoxy resin, or may contain two or more kinds of epoxy resins.

Phenol resins act as hardeners for epoxy resins, and such phenol resins include, for example, novolacs such as phenol novolac resins, phenol aralkyl resins, cresol novolac resins, tert-butylphenol novolak resins, and nonylphenol novolac resins. Type phenol resin can be mentioned. Further, examples of the phenol resin include a resol type phenol resin and polyoxystyrene such as polyparaoxystyrene. Particularly preferable as the phenol resin in the laser mark layer 11, is a phenol novolac resin or a phenol aralkyl resin. Further, the laser mark layer 11 may contain one kind of phenol resin or two or more kinds of phenol resins as a curing agent for the epoxy resin.

When the laser mark layer 11 contains an epoxy resin and a phenol resin as a curing agent thereof, the hydroxyl groups in the phenol resin are preferably 0.5 to 2.0 equivalents with respect to 1 equivalent of the epoxy groups in the epoxy resin. Both resins are blended at a ratio of preferably 0.8 to 1.2 equivalents. Such a configuration is preferable in order to sufficiently proceed the curing reaction of the epoxy resin and the phenol resin when the laser mark layer 11 is cured.

The content ratio of the thermosetting resin in the laser mark layer 11 is preferably 5 to 60% by mass, and more preferably 10 to 50% by mass from the viewpoint of appropriately curing the laser mark layer 11.

The thermoplastic resin in the laser mark layer 11 has, for example, a binder function, and when the laser mark layer 11 has a composition containing a thermosetting resin and a thermoplastic resin, the thermoplastic resin is, for example, acrylic. Resin, natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, 6 Examples thereof include polyamide resins such as nylon and 6,6-nylon, phenoxy resins, saturated polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyamideimide resins, and fluororesins. The laser mark layer 11 may contain one kind of thermoplastic resin, or may contain two or more kinds of thermoplastic resins. The acrylic resin is preferable as the thermoplastic resin in the laser mark layer 11 because it has few ionic impurities and high heat resistance.

When the laser mark layer 11 contains an acrylic resin as a thermoplastic resin, the acrylic resin preferably contains the most monomer units derived from the (meth) acrylic acid ester in terms of mass ratio. "(Meta) acrylic" shall mean "acrylic" and / or "methacryl".

Examples of the (meth) acrylic acid ester for forming the monomer unit of the acrylic resin, that is, the (meth) acrylic acid ester which is a constituent monomer of the acrylic resin include (meth) acrylic acid alkyl ester and (meth) acrylic acid cyclo. Alkyl esters and (meth) acrylic acid aryl esters can be mentioned. Examples of the (meth) acrylic acid alkyl ester include methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester and iso of (meth) acrylic acid. Pentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester (ie lauryl ester), tridecyl ester, tetradecyl ester , Hexadecyl ester, octadecyl ester, and ecosil ester. Examples of the (meth) acrylic acid cycloalkyl ester include cyclopentyl ester and cyclohexyl ester of (meth) acrylic acid. Examples of the (meth) acrylic acid aryl ester include phenyl (meth) acrylic acid and benzyl (meth) acrylic acid. As the constituent monomer of the acrylic resin, one kind of (meth) acrylic acid ester may be used, or two or more kinds of (meth) acrylic acid esters may be used. Further, the acrylic resin can be obtained by polymerizing a raw material monomer for forming the acrylic resin. Examples of the polymerization method include solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization.

The acrylic resin may be composed of one or more other monomers copolymerizable with the (meth) acrylic acid ester, for example, for the purpose of modifying its cohesive force and heat resistance. Examples of such a monomer include a carboxy group-containing monomer, an acid anhydride monomer, a hydroxy group-containing monomer, an epoxy group-containing monomer, a sulfonic acid group-containing monomer, a phosphoric acid group-containing monomer, acrylamide, and acrylonitrile. Examples of the carboxy group-containing monomer 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, and ( Examples include 8-hydroxyoctyl acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) methyl (meth) acrylate. Examples of the epoxy group-containing monomer include glycidyl (meth) acrylate and methyl glycidyl (meth) acrylate. Examples of the sulfonic acid group-containing monomer include styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, and (meth) acryloyloxynaphthalene sulfonic acid. Can be mentioned. Examples of the phosphoric acid group-containing monomer include 2-hydroxyethylacryloyl phosphate.

The acrylic resin contained in the laser mark layer 11 is preferably a copolymer of a monomer appropriately selected from butyl acrylate, ethyl acrylate, acrylonitrile, and acrylic acid. Such a configuration is preferable in the film 10 which is the back surface protective film, in order to achieve both the visibility of the engraved information by laser marking and the good splittability described later in the splitting expanding step.

When the laser mark layer 11 has a composition containing a thermoplastic resin with a thermosetting functional group, for example, a thermosetting functional group-containing acrylic resin can be used as the thermoplastic resin. The acrylic resin for forming this thermosetting functional group-containing acrylic resin preferably contains the most monomer unit derived from the (meth) acrylic acid ester in terms of mass ratio. As such a (meth) acrylic acid ester, for example, the same (meth) acrylic acid ester as described above can be used as the constituent monomer of the acrylic resin contained in the laser mark layer 11. The acrylic resin for forming a thermosetting functional group-containing acrylic resin may be one or more types that can be copolymerized with a (meth) acrylic acid ester, for example, because of its cohesiveness and heat resistance modification. It may contain a monomer unit derived from the monomer of. As such a monomer, for example, the above-mentioned monomer can be used as another monomer copolymerizable with the (meth) acrylic acid ester for forming the acrylic resin in the laser mark layer 11. On the other hand, examples of the thermosetting functional group for forming a thermosetting functional group-containing acrylic resin include a glycidyl group, a carboxy group, a hydroxy group, and an isocyanate group. Of these, a glycidyl group and a carboxy group can be preferably used. That is, as the thermosetting functional group-containing acrylic resin, a glycidyl group-containing acrylic resin or a carboxy group-containing acrylic resin can be preferably used. Further, a curing agent capable of reacting with the thermosetting functional group is selected according to the type of the thermosetting functional group in the thermosetting functional group-containing acrylic resin. When the thermosetting functional group of the thermosetting functional group-containing acrylic resin is a glycidyl group, the same phenol resin as described above can be used as the curing agent for the epoxy resin.

The composition for forming the laser mark layer 11 preferably contains a thermosetting catalyst. The blending of the thermosetting catalyst into the composition for forming the laser mark layer is preferable in order to sufficiently proceed the curing reaction of the resin component in curing the laser mark layer 11 and to increase the curing reaction rate. Examples of such a thermosetting catalyst include imidazole compounds, triphenylphosphine compounds, amine compounds, and trihalogen borane compounds. Examples of the imidazole compound 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 Rium trimeritate, 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-triazine isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole Can be mentioned. Examples of the triphenylphosphine compound include triphenylphosphine, tributylphosphine, tri (p-methylphenyl) phosphine, tri (nonylphenyl) phosphine, diphenyltrilphosphine, tetraphenylphosphonium bromide, and methyltriphenylphosphonium. , Methyltriphenylphosphonium chloride, methoxymethyltriphenylphosphonium, and benzyltriphenylphosphonium chloride. The triphenylphosphine-based compound shall also include a compound having both a triphenylphosphine structure and a triphenylborane structure. Examples of such compounds include tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra-p-triborate, benzyltriphenylphosphonium tetraphenylborate, and triphenylphosphine triphenylborane. Examples of amine compounds include monoethanolamine trifluoroborate and dicyandiamide. Examples of the trihalogen borane compound include trichloroborane. The composition for forming a laser mark layer may contain one kind of thermosetting catalyst, or may contain two or more kinds of thermosetting catalysts.

The laser mark layer 11 may contain a filler. The blending of the filler in the laser mark layer 11 is preferable in order to adjust the physical properties such as the elastic modulus of the laser mark layer 11, the yield point strength, and the elongation at break. Examples of the filler include an inorganic filler and an organic filler. Examples of the constituent materials of the inorganic filler include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whisker, and nitrided material. Included are boron, crystalline silica, and amorphous silica. Examples of the constituent material of the inorganic filler include elemental metals such as aluminum, gold, silver, copper and nickel, alloys, amorphous carbon and graphite. Examples of the constituent material of the organic filler include polymethyl methacrylate (PMMA), polyimide, polyamideimide, polyetheretherketone, polyetherimide, and polyesterimide. The laser mark layer 11 may contain one kind of filler or may contain two or more kinds of fillers. The filler may have various shapes such as a spherical shape, a needle shape, and a flake shape. When the laser mark layer 11 contains a filler, the average particle size of the filler is preferably 30 to 500 nm, more preferably 40 to 400 nm, and more preferably 50 to 300 nm. That is, the laser mark layer 11 preferably contains a nanofiller. The configuration in which the laser mark layer 11 contains a nanofiller having such a particle size as a filler is suitable for ensuring high breakability and high breakability of the film 10 to be fragmented. The average particle size of the filler can be determined using, for example, a luminous intensity type particle size distribution meter (trade name “LA-910”, manufactured by HORIBA, Ltd.). When the laser mark layer 11 contains a filler, 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. The content is preferably 50% by mass or less, more preferably 47% by mass or less, and more preferably 45% by mass or less.

The laser mark layer 11 contains a colorant in this embodiment. The colorant may be a pigment or a dye. Examples of the colorant include a black colorant, a cyan colorant, a magenta colorant, and a yellow colorant. In order to realize high visibility of the information stamped on the laser mark layer 11 by the laser marking, the laser mark layer 11 preferably contains a black colorant. Examples of black colorants include azo pigments such as carbon black, graphite (graphite), copper oxide, manganese dioxide, and azomethine azo black, aniline black, perylene black, titanium black, cyanine black, activated carbon, ferrite, magnetite, and oxidation. Examples thereof include chromium, iron oxide, molybdenum disulfide, composite oxide-based black dye, anthraquinone-based organic black dye, and azo-based organic black dye. Examples of carbon black include furnace black, channel black, acetylene black, thermal black, and lamp black. Examples of the black colorant include CI Solvent Black 3, 7, 22, 27, 29, 34, 43, and 70. Examples of the black colorant include CI Direct Black 17, 19, 22, 22, 32, 38, 51, and 71. Examples of black colorants include CI Acid Black 1, 2, 24, 26, 31, 48, 52, 107, 109, 110, 119, and 154. Be done. Examples of the black colorant include CI Dispers Black 1, 3, 3, 10, and 24. Examples of the black colorant include CI Pigment Black 1 and 7. The laser mark layer 11 may contain one kind of colorant or may contain two or more kinds of colorants. The content of the colorant in the laser mark layer 11 is preferably 0.5% by weight or more, more preferably 1% by weight or more, and more preferably 2% by weight or more. The content is preferably 10% by weight or less, more preferably 8% by weight or less, and more preferably 5% by weight or less. These configurations regarding the colorant content are preferable in order to realize high visibility of the information imprinted on the laser mark layer 11 by the laser marking.

The laser mark layer 11 may contain one kind or two or more kinds of other components, if necessary. Examples of the other component include a flame retardant, a silane coupling agent, and an ion trapping agent. Flame retardants include, for example, antimony trioxide, antimony pentoxide, and brominated epoxy resins. Examples of the silane coupling agent include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane. Examples of the ion trapping agent include hydrotalcites, bismuth hydroxide, hydroxide-containing antimony (for example, "IXE-300" manufactured by Toa Synthetic Co., Ltd.), and zirconium phosphate having a specific structure (for example, "IXE-300" manufactured by Toa Synthetic Co., Ltd.). IXE-100 "), magnesium silicate (for example," Kyoward 600 "manufactured by Kyowa Chemical Industry Co., Ltd.), and aluminum silicate (for example," Kyoward 700 "manufactured by Kyowa Chemical Industry Co., Ltd.). A compound capable of forming a complex with a metal ion can also be used as an ion trapping agent. Examples of such compounds include triazole-based compounds, tetrazole-based compounds, and bipyridyl-based compounds. Of these, a triazole-based compound is preferable from the viewpoint of the stability of the complex formed with the metal ion. 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-dihydroxypropyl) benzotriazole, 1- (1) , 2-Dicarboxydiethyl) benzotriazole, 1- (2-ethylhexylaminomethyl) benzotriazole, 2,4-di-t-pentyl-6-{(H-benzotriazole-1-yl) methyl} phenol, 2 -(2-Hydroxy-5-t-butylphenyl) -2H-benzotriazole, octyl-3- [3-t-butyl-4-hydroxy-5- (5-chloro-2-H-benzotriazole-2-yl) Phenyl] propionate, 2-ethylhexyl-3- [3-t-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazole-2-yl) phenyl] propionate, 2- (2H-benzotriazole-2) -Il) -6- (1-Methyl-1-phenylethyl) -4- (1,1,3,3-tetramethylbutyl) phenol, 2- (2H-benzotriazole-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-Chlorobenzotriazole, 2- [2-hydroxy-3,5-di (1,1-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2'-methylenebis [6- (2H) -Benzotriazole-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol], 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl]- Examples thereof include 2H-benzotriazole and methyl-3- [3- (2H-benzotriazole-2-yl) -5-t-butyl-4-hydroxyphenyl] propionate. Further, a predetermined hydroxyl group-containing compound such as a quinol compound, a hydroxyanthraquinone compound, and a polyphenol compound can also be used as an ion trap agent. Specific examples of such hydroxyl group-containing compounds include 1,2-benzenediol, alizarin, anthralphin, tannin, gallic acid, methyl gallic acid, and pyrogallol.

The adhesive layer 12 in the film 10 may have a composition containing a thermosetting resin and a thermoplastic resin as a resin component, or is accompanied by a thermosetting functional group capable of reacting with the curing agent to form a bond. It may have a composition containing a thermoplastic resin. When the adhesive layer 12 has a composition containing a thermoplastic resin with a thermosetting functional group, the adhesive layer 12 does not need to further contain the thermosetting resin.

When the adhesive layer 12 has a composition containing a thermosetting resin and a thermoplastic resin, the thermosetting resin includes, for example, an epoxy resin, a phenol resin, an amino resin, an unsaturated polyester resin, a polyurethane resin, and a silicone resin. , And thermosetting polyimide resin. The adhesive layer 12 may contain one type of thermosetting resin, or may contain two or more types of thermosetting resins. Since the epoxy resin tends to have a small content of ionic impurities and the like that can cause corrosion of the semiconductor chip to be protected by the back surface protective film formed from the film 10 as described later, the adhesive of the film 10 It is preferable as the thermosetting resin in the layer 12.

Examples of the epoxy resin in the adhesive layer 12 include those described above as the epoxy resin which is the thermosetting resin when the laser mark layer 11 has a composition containing a thermosetting resin and a thermoplastic resin. Phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, biphenyl type epoxy resin, trishydroxyphenylmethane type epoxy resin, and tetraphenylol ethane type epoxy resin are highly reactive and heat resistant with phenol resin as a curing agent. It is preferable as the epoxy resin in the adhesive layer 12 because of its excellent properties.

Examples of the phenol resin that can act as a curing agent for the epoxy resin in the adhesive layer 12 include those described above as the phenol resin that is the curing agent for the epoxy resin in the laser mark layer 11. The adhesive layer 12 may contain one kind of phenol resin or two or more kinds of phenol resins as a curing agent for the epoxy resin.

When the adhesive layer 12 contains an epoxy resin and a phenol resin as a curing agent thereof, the hydroxyl groups in the phenol resin are preferably 0.5 to 2.0 equivalents with respect to 1 equivalent of the epoxy groups in the epoxy resin. Both resins are blended at a ratio of preferably 0.8 to 1.2 equivalents. Such a configuration is preferable in order to sufficiently proceed the curing reaction of the epoxy resin and the phenol resin when the adhesive layer 12 is cured.

The content ratio of the thermosetting resin in the adhesive layer 12 is preferably 5 to 60% by mass, and more preferably 10 to 50% by mass from the viewpoint of appropriately curing the adhesive layer 12.

The thermoplastic resin in the adhesive layer 12 has, for example, a binder function. When the adhesive layer 12 has a composition containing a thermosetting resin and a thermoplastic resin, as the thermoplastic resin, for example, when the laser mark layer 11 has a composition containing a thermosetting resin and a thermoplastic resin. Examples of the above-mentioned thermoplastic resin can be mentioned. The adhesive layer 12 may contain one kind of thermoplastic resin, or may contain two or more kinds of thermoplastic resins. Acrylic resin is preferable as a thermoplastic resin in the adhesive layer 12 because it has few ionic impurities and high heat resistance.

When the adhesive layer 12 contains an acrylic resin as a thermoplastic resin, the acrylic resin preferably contains the most monomer units derived from the (meth) acrylic acid ester in terms of mass ratio. As the (meth) acrylic acid ester for forming a monomer unit of such an acrylic resin, for example, the above-mentioned (meth) as a constituent monomer of the acrylic resin when the laser mark layer 11 contains an acrylic resin as a thermoplastic resin. ) Acrylic acid ester can be used. As the constituent monomer of the acrylic resin in the adhesive layer 12, one kind of (meth) acrylic acid ester may be used, or two or more kinds of (meth) acrylic acid esters may be used. Further, the acrylic resin may be composed of one or two or more other monomers copolymerizable with the (meth) acrylic acid ester, for example, in order to modify its cohesive force and heat resistance. As such a monomer, for example, the above-mentioned monomer can be used as another monomer copolymerizable with the (meth) acrylic acid ester for forming the acrylic resin in the laser mark layer 11.

The acrylic resin contained in the adhesive layer 12 is a copolymer of a monomer appropriately selected from butyl acrylate, ethyl acrylate, acrylonitrile, and acrylic acid. Such a configuration is preferable in the film 10 which is the back surface protective film, in order to achieve both adhesiveness to the work and good splitting property described later in the expanding step for cutting.

When the adhesive layer 12 has a composition containing a thermoplastic resin with a thermosetting functional group, for example, a thermosetting functional group-containing acrylic resin can be used as the thermoplastic resin. The acrylic resin for forming this thermosetting functional group-containing acrylic resin preferably contains the most monomer unit derived from the (meth) acrylic acid ester in terms of mass ratio. As such a (meth) acrylic acid ester, for example, the same (meth) acrylic acid ester as described above can be used as the constituent monomer of the acrylic resin contained in the laser mark layer 11. The acrylic resin for forming a thermosetting functional group-containing acrylic resin may be one or more types that can be copolymerized with a (meth) acrylic acid ester, for example, because of its cohesiveness and heat resistance modification. It may contain a monomer unit derived from the monomer of. As such a monomer, for example, the above-mentioned monomer can be used as another monomer copolymerizable with the (meth) acrylic acid ester for forming the acrylic resin in the laser mark layer 11. On the other hand, examples of the thermosetting functional group for forming a thermosetting functional group-containing acrylic resin include a glycidyl group, a carboxy group, a hydroxy group, and an isocyanate group. Of these, a glycidyl group and a carboxy group can be preferably used. Further, a curing agent capable of reacting with the thermosetting functional group is selected according to the type of the thermosetting functional group in the thermosetting functional group-containing acrylic resin. When the thermosetting functional group of the thermosetting functional group-containing acrylic resin is a glycidyl group, the same phenol resin as described above can be used as the curing agent for the epoxy resin.

The composition for forming the adhesive layer 12 preferably contains a thermosetting catalyst. The addition of the thermosetting catalyst to the composition for forming the adhesive layer is preferable in order to sufficiently proceed the curing reaction of the resin component in the curing of the adhesive layer 12 and to increase the curing reaction rate. As such a thermosetting catalyst, for example, the above-mentioned thermosetting catalyst that can be blended in the composition for forming a laser mark layer can be used.

The adhesive layer 12 may contain a filler. The blending of the filler into the adhesive layer 12 is preferable in order to adjust the physical properties such as the elastic modulus of the adhesive layer 12, the yield point strength, and the elongation at break. Examples of the filler in the adhesive layer 12 include those described above as the filler in the laser mark layer 11. The adhesive layer 12 may contain one kind of filler or may contain two or more kinds of fillers. The filler may have various shapes such as a spherical shape, a needle shape, and a flake shape. When the adhesive layer 12 contains a filler, the average particle size of the filler is preferably 30 to 500 nm, more preferably 40 to 400 nm, and more preferably 50 to 300 nm. That is, the adhesive layer 12 preferably contains a nanofiller. The configuration in which the adhesive layer 12 contains nanofillers having such a particle size as a filler avoids damage to the work to be attached or mounted on the film 10 due to the filler contained in the adhesive layer 12. Alternatively, it is suitable for suppressing the film 10 and for ensuring high breakability and high splittability for the film 10 to be fragmented. When the adhesive layer 12 contains a filler, 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. The content is preferably 50% by mass or less, more preferably 47% by mass or less, and more preferably 45% by mass or less.

The adhesive layer 12 may contain a colorant. Examples of the colorant in the adhesive layer 12 include those described above as the colorant in the laser mark layer 11. In order to secure high contrast between the engraved portion by the laser marking on the laser mark layer 11 side of the film 10 and the other portion and realize good visibility of the engraved information, the adhesive layer 12 is black. It preferably contains a colorant. The adhesive layer 12 may contain one kind of colorant or may contain two or more kinds of colorants. The content of the colorant in the adhesive layer 12 is preferably 0.5% by weight or more, more preferably 1% by weight or more, and more preferably 2% by weight or more. The content is preferably 10% by weight or less, more preferably 8% by weight or less, and more preferably 5% by weight or less. These configurations regarding the colorant content are preferable in order to realize the above-mentioned good visibility of the marking information by laser marking.

The adhesive layer 12 may contain one kind or two or more kinds of other components, if necessary. Examples of the other component include the flame retardant, the silane coupling agent, and the ion trapping agent specifically described above for the laser mark layer 11.

In the film 10 which is the back surface protective film, the thickness of the laser mark layer 11 is, for example, 5 to 22, and the thickness of the adhesive layer 12 is, for example, 3 to 20. The value of the ratio of the thickness of the laser mark layer 11 to the thickness of the adhesive layer 12 is preferably 1 or more, more preferably 1.5 or more, and more preferably 2 or more. The value of the ratio is, for example, 8 or less.

When the film 10 is heat-treated at 120 ° C. for 2 hours, it is measured for a back surface protective film sample piece having a width of 10 mm under the conditions of an initial chuck distance of 22.5 mm, a frequency of 1 Hz, and a heating rate of 10 ° C./min. The tensile storage elastic modulus at ° C. is 0.5 GPa or more, preferably 0.75 GPa or more, and more preferably 1 GPa or more. The tensile storage elastic modulus of the film 10 can be adjusted, for example, by adjusting the blending ratio of a thermoplastic component such as an acrylic resin and a thermosetting component such as an epoxy resin or a phenol resin. This tensile storage elastic modulus can be determined based on the dynamic viscoelasticity measurement performed using a dynamic viscoelasticity measuring device (trade name "Solid Analyzer RS GII", manufactured by Leometric Co., Ltd.). In the measurement, the size of the sample piece (back surface protective film sample piece) cut out from the back surface protective film is set to width 10 mm × length 30 mm (thickness is, for example, 25 μm), and the initial chuck distance of the sample piece holding chuck. 22.5 mm, the measurement mode is the tension mode, the measurement environment is a nitrogen atmosphere, the measurement temperature range is 0 ° C. to 100 ° C., the frequency is 1 Hz, and the temperature rise rate is 10 ° C./min.

Further, the film 10 has a calorific value in the range of 50 to 200 ° C. in the differential scanning calorimetry at a heating rate of 10 ° C./min, preferably 40 J / g or less, more preferably 35 J / g or less, more preferably. Is 30 J / g or less. Such adjustment of the calorific value with respect to the film 10 can be adjusted, for example, by selecting the type of the thermosetting catalyst blended in each layer of the film 10 and adjusting the blending amount. The differential scanning calorimetry can be performed using a differential scanning calorimeter (trade name "DSC Q2000", manufactured by TA Instruments). In the measurement, the measurement environment is a nitrogen atmosphere, the measurement temperature range is −20 ° C. to 300 ° C., and the temperature rise rate is 10 ° C./min. When the exothermic peak appears in the range of 50 to 200 ° C. in the DSC chart obtained by the measurement, the integrated value of the calorific value above the baseline at 50 to 200 ° C. of the chart is taken as the calorific value.

The base material 21 of the dicing tape 20 in the dicing tape integrated back surface protective film X is an element that functions as a support in the dicing tape 20 or the dicing tape integrated back surface protective film X. The base material 21 is, for example, a plastic base material, and a plastic film can be preferably used as the plastic base material. Examples of the constituent materials of the plastic base material include polyolefin, polyester, polyurethane, polycarbonate, polyether ether ketone, polyimide, polyetherimide, polyamide, total aromatic polyamide, polyvinyl chloride, polyvinylidene chloride, polyphenyl sulfide, and aramid. , Fluororesin, Cellulosic resin, and Silicone resin. Examples of polyolefins include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymerized polypropylene, block copolymerized polypropylene, homopolyprolene, polybutene, and polymethylpentene. Examples include ethylene-vinyl acetate copolymer, ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester copolymer, ethylene-butene copolymer, and ethylene-hexene copolymer. Be done. Examples of polyesters include polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate. The base material 21 may be made of one kind of material or may be made of two or more kinds of materials. The base material 21 may have a single-layer structure or a multi-layer structure. When the pressure-sensitive adhesive layer 22 on the base material 21 is UV-curable as described later, the base material 21 preferably has UV-transmissibility. When the base material 21 is made of a plastic film, it may be a non-stretched film, a uniaxially stretched film, or a biaxially stretched film. In the present embodiment, the base material 21 is preferably a base material made of polyvinyl chloride or a base material made of an ethylene-vinyl acetate copolymer.

When the dicing tape 20 or the base material 21 is shrunk by, for example, partial heating when the dicing tape integrated back surface protective film X is used, the base material 21 is preferably heat-shrinkable. When the base material 21 is made of a plastic film, the base material 21 is preferably a biaxially stretched film in order to realize isotropic heat shrinkage of the dicing tape 20 or the base material 21. The dicing tape 20 to the base material 21 has a heat shrinkage rate of preferably 2 to 30%, more preferably 2 to 25%, and more preferably 2 to 25% in a heat treatment test conducted under the conditions of a heating temperature of 100 ° C. and a heat treatment time of 60 seconds. It is 3 to 20%, more preferably 5 to 20%. The heat shrinkage rate refers to at least one of the so-called MD direction heat shrinkage rate and the so-called TD direction heat shrinkage rate.

The surface of the base material 21 on the pressure-sensitive adhesive layer 22 side may be subjected to a physical treatment, a chemical treatment, or an undercoating treatment for enhancing the adhesion to the pressure-sensitive adhesive layer 22. Physical treatments include, for example, corona treatment, plasma treatment, sandmat treatment, ozone exposure treatment, flame exposure treatment, high-voltage impact exposure treatment, and ionizing radiation treatment. Examples of the chemical treatment include chromic acid treatment.

The thickness of the base material 21 is preferably 40 μm or more, preferably 50 μm or more, from the viewpoint of ensuring the strength for the base material 21 to function as a support in the dicing tape 20 or the back surface protective film X integrated with the dicing tape. , More preferably 60 μm or more. Further, from the viewpoint of realizing appropriate flexibility in the dicing tape 20 or the dicing tape integrated back surface protective film X, the thickness of the base material 21 is preferably 200 μm or less, more preferably 180 μm or less, and more preferably. It is 150 μm or less.

The pressure-sensitive adhesive layer 22 of the dicing tape 20 contains a pressure-sensitive adhesive. This adhesive may be an adhesive (adhesive that can reduce the adhesive force) that can intentionally reduce the adhesive force by an external action in the process of using the back surface protective film X integrated with the dicing tape. However, it may be an adhesive (adhesive strength non-reducing type adhesive) in which the adhesive strength is hardly or not reduced by an external action in the process of using the back surface protective film X integrated with the dicing tape. Whether to use a pressure-reducing adhesive or a non-reducing adhesive as the pressure-sensitive adhesive in the pressure-sensitive adhesive layer 22 is separated by using a dicing tape-integrated back surface protective film X. It can be appropriately selected according to the usage mode of the back surface protective film X integrated with the dicing tape, such as the method and conditions for individualizing the semiconductor chip. When a pressure-reducing adhesive is used as the adhesive in the adhesive layer 22, it is relative to the state in which the adhesive layer 22 exhibits relatively high adhesive strength in the process of using the back surface protective film X integrated with the dicing tape. It is possible to use the state showing low adhesive strength properly.

Examples of such an adhesive force-reducable adhesive include an adhesive (radiation-curable adhesive) that can be cured by irradiation in the process of using the back surface protective film X integrated with a dicing tape. In the pressure-sensitive adhesive layer 22 of the present embodiment, one type of pressure-reducing pressure-sensitive adhesive may be used, or two or more types of pressure-reducing pressure-sensitive adhesive may be used. Further, the entire pressure-sensitive adhesive layer 22 may be formed of a pressure-reducing type pressure-sensitive adhesive, or a part of the pressure-sensitive adhesive layer 22 may be formed of a pressure-reducing type pressure-sensitive adhesive. For example, when the pressure-sensitive adhesive layer 22 has a single-layer structure, the entire pressure-sensitive adhesive layer 22 may be formed of a pressure-reducing adhesive, or a predetermined portion of the pressure-sensitive adhesive layer 22 (for example, a work can be attached). The central area, which is the area to be attached, is formed of a pressure-reducing adhesive, and other parts (for example, the area to be applied to the ring frame, which is outside the central area) are non-reduced in adhesive force. It may be formed from a mold adhesive. Further, when the pressure-sensitive adhesive layer 22 has a multi-layer structure, all the layers forming the multi-layer structure may be formed of a pressure-reducing adhesive, and some layers in the multi-layer structure may be a type that can reduce the pressure. It may be formed from an adhesive.

Examples of the radiation-curable pressure-sensitive adhesive for the pressure-sensitive adhesive layer 22 include pressure-sensitive adhesives that are cured by irradiation with electron beams, ultraviolet rays, α-rays, β-rays, γ-rays, or X-rays. A curable type pressure-sensitive adhesive (ultraviolet curable pressure-sensitive adhesive) can be particularly preferably used.

The radiation-curable pressure-sensitive adhesive for the pressure-sensitive adhesive layer 22 includes, for example, a base polymer such as an acrylic polymer which is an acrylic pressure-sensitive adhesive, and a radiation-polymerizable product having a functional group such as a radiation-polymerizable carbon-carbon double bond. Examples thereof include an additive-type radiation-curable pressure-sensitive adhesive containing the above-mentioned monomer component and oligomer component.

The above acrylic polymer preferably contains the most monomer unit derived from the (meth) acrylic acid ester in terms of mass ratio. Examples of the (meth) acrylic acid ester for forming the monomer unit of the acrylic polymer, that is, the (meth) acrylic acid ester which is a constituent monomer of the acrylic polymer, include (meth) acrylic acid alkyl ester and (meth) acrylic. Acid cycloalkyl esters and (meth) acrylic acid aryl esters can be mentioned, and more specifically, (meth) acrylic acid esters similar to those described above for the acrylic resin in the laser mark layer 11 of the film 10 can be mentioned. As the constituent monomer of the acrylic polymer, one kind of (meth) acrylic acid ester may be used, or two or more kinds of (meth) acrylic acid esters may be used. Preferred examples of the constituent monomers of the acrylic polymer include 2-ethylhexyl acrylate and lauryl acrylate. Further, in order to appropriately express the basic properties such as the adhesiveness due to the (meth) acrylic acid ester in the pressure-sensitive adhesive layer 22, the ratio of the (meth) acrylic acid ester in the entire constituent monomers of the acrylic polymer is preferable. It is 40% by mass or more, more preferably 60% by mass or more.

Acrylic polymers include monomer units derived from one or more other monomers copolymerizable with (meth) acrylic acid esters, for example due to modification of their cohesiveness and heat resistance. May be good. Such monomers include, for example, carboxy group-containing monomers, acid anhydride monomers, hydroxy group-containing monomers, epoxy group-containing monomers, sulfonic acid group-containing monomers, phosphate group-containing monomers, acrylamide, and acrylonitrile, and more. Specifically, the above-mentioned ones can be mentioned as other monomers copolymerizable with the (meth) acrylic acid ester for forming the acrylic resin in the laser mark layer 11 of the film 10.

The acrylic polymer may contain a monomer unit derived from a polyfunctional monomer copolymerizable with a monomer component such as (meth) acrylic acid ester in order to form a crosslinked structure in the polymer skeleton. Such polyfunctional monomers include, for example, hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Pentaerythritol di (meth) acrylate, trimethylolpropanthry (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, polyglycidyl (meth) acrylate, polyester (meth) acrylate, and urethane ( Meta) acrylate can be mentioned. "(Meta) acrylate" shall mean "acrylate" and / or "methacrylate". As the constituent monomer of the acrylic polymer, one kind of polyfunctional monomer may be used, or two or more kinds of polyfunctional monomers may be used. In order to appropriately express the basic properties such as adhesiveness due to the (meth) acrylic acid ester in the pressure-sensitive adhesive layer 22, the ratio of the polyfunctional monomer in the total constituent monomers of the acrylic polymer is preferably 40% by mass or less. It is preferably 30% by mass or less.

The acrylic polymer can be obtained by polymerizing a raw material monomer for forming the acrylic polymer. Examples of the polymerization method include solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization. From the viewpoint of high cleanliness in the method for manufacturing a semiconductor device in which the dicing tape 20 or the dicing tape integrated back surface protective film X is used, the low in the adhesive layer 22 in the dicing tape 20 or the dicing tape integrated back surface protective film X. Where the amount of the molecular weight substance is preferably small, the number average molecular weight of the acrylic polymer is preferably 100,000 or more, more preferably 200,000 to 3 million.

The pressure-sensitive adhesive layer 22 or the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 22 may contain, for example, an external cross-linking agent in order to increase the number average molecular weight of the base polymer such as an acrylic polymer. Examples of the external cross-linking agent for reacting with a base polymer such as an acrylic polymer to form a cross-linked structure include a polyisocyanate compound, an epoxy compound, a polyol compound, an aziridine compound, and a melamine-based cross-linking agent. The content of the external cross-linking agent in the pressure-sensitive adhesive layer 22 or the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 22 is preferably 5 parts by mass or less, and more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the base polymer.

Examples of the above-mentioned radiopolymerizable monomer component for forming a radiation-curable pressure-sensitive adhesive include urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetra (meth). Examples include acrylates, dipentaerythritol monohydroxypenta (meth) acrylates, dipentaerythritol hexa (meth) acrylates, and 1,4-butanediol di (meth) acrylates. Examples of the above-mentioned radiation-polymerizable oligomer component for forming a radiation-curable pressure-sensitive adhesive include various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based, and have a molecular weight of about 100 to 30,000. The one is suitable. The total content of the radiation-polymerizable monomer component and the oligomer component in the radiation-curable pressure-sensitive adhesive is determined within a range in which the adhesive strength of the formed pressure-sensitive adhesive layer 22 can be appropriately reduced, and a base polymer such as an acrylic polymer is used. It is preferably 5 to 500 parts by mass, and more preferably 40 to 150 parts by mass with respect to 100 parts by mass. Further, as the additive-type radiation-curable pressure-sensitive adhesive, for example, those disclosed in Japanese Patent Application Laid-Open No. 60-196956 may be used.

As the radiation-curable pressure-sensitive adhesive for the pressure-sensitive adhesive layer 22, for example, a base polymer having a functional group such as a radiation-polymerizable carbon-carbon double bond at the end of the polymer main chain in the polymer side chain or the polymer main chain. Also included is an intrinsically curable pressure-sensitive adhesive containing. Such an intrinsically curable pressure-sensitive adhesive is suitable for suppressing an unintended change in adhesive properties over time due to the movement of low molecular weight components in the formed pressure-sensitive adhesive layer 22.

As the base polymer contained in the intrinsic radiation-curable pressure-sensitive adhesive, a polymer having an acrylic polymer as a basic skeleton is preferable. As the acrylic polymer forming such a basic skeleton, the above-mentioned acrylic polymer can be adopted. As a method for introducing a radiation-polymerizable carbon-carbon double bond into an acrylic polymer, for example, a raw material monomer containing a monomer having a predetermined functional group (first functional group) is copolymerized to obtain an acrylic polymer. After obtaining the compound, a compound having a predetermined functional group (second functional group) capable of reacting with the first functional group and being bonded to the first functional group and a radiopolymerizable carbon-carbon double bond can be obtained as carbon-carbon. Examples thereof include a method of subjecting an acrylic polymer to a condensation reaction or an addition reaction while maintaining the radiation polymerizable property of the double bond.

Examples of the combination of the first functional group and the second functional group include 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, and an isocyanate group. And hydroxy groups. Of these combinations, a combination of a hydroxy group and an isocyanate group or a combination of an isocyanate group and a hydroxy group is preferable from the viewpoint of ease of reaction tracking. Further, since it is technically difficult to prepare a polymer having a highly reactive isocyanate group, from the viewpoint of easy preparation or availability of an acrylic polymer, the first functionality on the acrylic polymer side is described above. It is more preferable that the group is a hydroxy group and the second functional group is an isocyanate group. In this case, the isocyanate compound having both a radiopolymerizable carbon-carbon double bond and an isocyanate group as a second functional group, that is, a radiopolymerizable unsaturated functional group-containing isocyanate compound is, for example, methacryloyl isocyanate, 2 Included are methacryloyloxyethyl isocyanate (MOI), and m-isopropenyl-α, α-dimethylbenzyl isocyanate.

The radiation curable pressure-sensitive adhesive for the pressure-sensitive adhesive layer 22 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, and camphor. Included are quinone, halogenated ketones, acylphosphinoxides, and acylphosphonates. Examples of α-ketol compounds include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α'-dimethylacetophenone, and 2-methyl-2-hydroxypro. Examples include piophenone and 1-hydroxycyclohexylphenyl ketone. Examples of acetophenone compounds include methoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2-diethoxyacetophenone, and 2-methyl-1- [4- (methylthio)-. Phenyl] -2-morpholinopropane-1 can be mentioned. Examples of benzoin ether compounds include benzoin ethyl ether, benzoin isopropyl ether, and anisoin methyl ether. Examples of the ketal-based compound include benzyldimethyl ketal. Examples of the aromatic sulfonyl chloride compound include 2-naphthalene sulfonyl chloride. Examples of the photoactive oxime compound include 1-phenyl-1,2-propanedione-2- (O-ethoxycarbonyl) oxime. Examples of benzophenone compounds include benzophenone, benzoylbenzoic acid, and 3,3'-dimethyl-4-methoxybenzophenone. Examples of thioxanthone compounds include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropyl. Examples include thioxanthone. The content of the photopolymerization initiator in the radiation-curable pressure-sensitive adhesive in the pressure-sensitive adhesive layer 22 is, for example, 0.05 to 20 parts by mass with respect to 100 parts by mass of a base polymer such as an acrylic polymer.

Examples of the above-mentioned non-reducing adhesive strength type adhesive include a pressure-sensitive pressure-sensitive adhesive and a pressure-sensitive pressure-sensitive adhesive, which is obtained by pre-curing the above-mentioned radiation-curable pressure-sensitive adhesive by irradiation with radiation. , Can be mentioned. Depending on the type and content of the polymer component contained therein, the radiation-curable pressure-sensitive adhesive can exhibit adhesiveness due to the polymer component even when the adhesive strength is reduced by radiation curing, and can be used in a predetermined mode of use. It is possible to exert the adhesive force that can be used to hold the adherend adhesively. In the pressure-sensitive adhesive layer 22 of the present embodiment, one kind of non-reducing adhesive strength type adhesive may be used, or two or more kinds of non-reducing pressure-sensitive adhesive strength may be used. Further, the entire pressure-sensitive adhesive layer 22 may be formed of a non-adhesive strength non-reducing type pressure-sensitive adhesive, or a part of the pressure-sensitive adhesive layer 22 may be formed of a non-adhesive strength non-reducing type pressure-sensitive adhesive. For example, when the pressure-sensitive adhesive layer 22 has a single-layer structure, the entire pressure-sensitive adhesive layer 22 may be formed of a non-adhesive strength-reduced pressure-sensitive adhesive, or as described above, a predetermined portion of the pressure-sensitive adhesive layer 22 ( For example, the area to be attached to the ring frame, which is outside the area to be attached to the wafer) is formed of the non-adhesive force-reducing adhesive, and other parts (for example, the area to be attached to the wafer). A central region) may be formed from a pressure-reducing adhesive. When the pressure-sensitive adhesive layer 22 has a multi-layer structure, all the layers forming the multi-layer structure may be formed of a non-adhesive strength non-reducing type pressure-sensitive adhesive, and some layers in the multi-layer structure may be non-adhesive strength non-reducing type. It may be formed from an adhesive.

On the other hand, as the pressure-sensitive pressure-sensitive adhesive for the pressure-sensitive adhesive layer 22, for example, an acrylic pressure-sensitive adhesive or a rubber-based pressure-sensitive adhesive using an acrylic polymer as a base polymer can be used. When the pressure-sensitive adhesive layer 22 contains an acrylic pressure-sensitive adhesive as a pressure-sensitive pressure-sensitive pressure-sensitive adhesive, the acrylic polymer, which is the base polymer of the acrylic pressure-sensitive adhesive, preferably contains a monomer unit derived from (meth) acrylic acid ester in a mass ratio. Including the most. Examples of such an acrylic polymer include the above-mentioned acrylic polymers for radiation-curable pressure-sensitive adhesives.

The pressure-sensitive adhesive layer 22 or a pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 22 may contain, in addition to the above-mentioned components, a cross-linking accelerator, a pressure-sensitive adhesive, an anti-aging agent, a colorant such as a pigment or a dye, and the like. The colorant may be a compound that is colored by being irradiated with radiation. Examples of such compounds include leuco dyes.

The thickness of the pressure-sensitive adhesive layer 22 is preferably 2 to 20 μm, more preferably 3 to 17 μm, and more preferably 5 to 15 μm. Such a configuration is suitable, for example, when the pressure-sensitive adhesive layer 22 contains a radiation-curable pressure-sensitive adhesive, in order to balance the adhesive force of the pressure-sensitive adhesive layer 22 with respect to the film 10 before and after radiation curing.

In the dicing tape integrated back surface protective film X, a peeling test is performed between the film 10 which is the back surface protective film and the adhesive layer 22 of the dicing tape 20 under the conditions of 23 ° C., a peeling angle of 180 °, and a tensile speed of 300 mm / min. In, the adhesive strength may be 0.1 N / 20 mm or less, preferably 0.08 N / 20 mm or less, and more preferably 0.06 N / 20 mm or less. Such low adhesive strength can be realized by preliminarily thermosetting the laser mark layer 11 on the dicing tape side of the film 10 before being bonded to the adhesive layer 22 of the dicing tape 20. This adhesive strength can be measured using a tensile tester (trade name "Autograph AG-X", manufactured by Shimadzu Corporation). Specifically, the method for producing the sample piece and the method for measuring the sample piece used for the measurement are as follows. First, a single-sided adhesive tape (trade name "BT-315", manufactured by Nitto Denko KK) is attached to the surface 12a of the film 10 on the back surface protective film X integrated with the dicing tape on the adhesive layer side. This bonding is performed by a crimping operation in which a 2 kg hand roller is reciprocated once. Next, a sample piece having a laminated structure of the dicing tape 20, the film 10, and the single-sided adhesive tape and having a width of 20 mm and a length of 100 mm is cut out from the bonded body. When the pressure-sensitive adhesive layer 22 contains a radiation-hard pressure-sensitive adhesive, the pressure-sensitive adhesive layer 22 is irradiated with radiation such as ultraviolet rays of ^{300 mJ / cm 2 from the side of the base material 21 in the dicing tape-integrated back surface protective film X.} After the pressure-sensitive adhesive layer 22 is cured, a sample piece is cut out. Then, using a tensile tester (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), a peel test is performed on the sample piece under the conditions of 23 ° C, a peel angle of 180 °, and a tensile speed of 300 mm / min. Then, the adhesive force between the adhesive layer 22 and the film 10 in the dicing tape integrated back surface protective film X is measured.

The dicing tape integrated back surface protective film X having the above configuration can be manufactured, for example, as follows.

In the production of the film 10 in the back surface protective film X integrated with the dicing tape, first, the resin film (first resin film) forming the laser mark layer 11 and the resin film (first resin film) forming the adhesive layer 12 are formed. 2 Resin film) and are prepared individually. The first resin film is produced by applying a resin composition for forming a laser mark layer on a predetermined separator to form a resin composition layer, and then drying and curing the composition layer by heating. Can be done. Examples of the separator include polyethylene terephthalate (PET) film, polyethylene film, polypropylene film, and plastic film and paper surface-coated with a release agent such as a fluorine-based release agent and a long-chain alkyl acrylate-based release agent. Can be mentioned. Examples of the method for applying the resin composition include roll coating, screen coating, and gravure coating. In the preparation of the first resin film, the heating temperature is, for example, 90 to 160 ° C., and the heating time is, for example, 2 to 4 minutes. On the other hand, the second resin film is produced by applying a resin composition for forming an adhesive layer on a predetermined separator to form a resin composition layer, and then drying the composition layer by heating. Can be done. In the preparation of the second resin film, the heating temperature is, for example, 90 to 150 ° C., and the heating time is, for example, 1 to 2 minutes. As described above, the above-mentioned first and second resin films can be produced in the form of each having a separator. Then, the exposed surfaces of the first and second resin films are bonded to each other. As a result, the film 10 having a laminated structure of the laser mark layer 11 and the adhesive layer 12 is produced.

The dicing tape 20 of the back surface protective film X integrated with the dicing tape can be produced by providing the pressure-sensitive adhesive layer 22 on the prepared base material 21. For example, the resin base material 21 is produced by a film forming method such as a calendar film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T die extrusion method, a coextrusion method, or a dry laminating method. can do. After the film formation, the film or the base material 21 is subjected to a predetermined surface treatment as needed. In the formation of the pressure-sensitive adhesive layer 22, for example, after preparing the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer, the composition is first applied on the base material 21 or a predetermined separator to form the pressure-sensitive adhesive composition layer. To form. Examples of the method for applying the pressure-sensitive adhesive composition include roll coating, screen coating, and gravure coating. Next, in this pressure-sensitive adhesive composition layer, it is dried by heating if necessary, and a cross-linking reaction is caused 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 separator is peeled off. As a result, the dicing tape 20 having a laminated structure of the base material 21 and the pressure-sensitive adhesive layer 22 is produced.

In the production of the back surface protective film X integrated with the dicing tape, next, the laser mark layer 11 side of the film 10 is attached to the adhesive layer 22 side of the dicing tape 20. The bonding temperature is, for example, 30 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 contains the above-mentioned radiation-curable pressure-sensitive adhesive, the pressure-sensitive adhesive layer 22 may be irradiated with radiation such as ultraviolet rays before the bonding, or the base material may be irradiated after the bonding. The pressure-sensitive adhesive layer 22 may be irradiated with radiation such as ultraviolet rays from the side of 21. Alternatively, such irradiation may not be performed in the manufacturing process of the dicing tape integrated back surface protective film X (in this case, the adhesive layer 22 is radiation-cured in the process of using the dicing tape integrated back surface protective film X). Is possible). When the pressure-sensitive adhesive layer 22 is an ultraviolet curable type, the amount of ultraviolet irradiation for curing the pressure-sensitive adhesive layer 22 is, for example, 50 to 500 mJ / cm ² . In the dicing tape integrated back surface protective film X, the region (irradiation region R) where the pressure-sensitive adhesive layer 22 is irradiated as a measure for reducing the adhesive strength is, for example, as shown in FIG. 1, the die-bond film bonding region in the pressure-sensitive adhesive layer 22. It is the area excluding the peripheral part of the inside.

As described above, the dicing tape integrated back surface protective film X can be produced. The dicing tape-integrated back surface protective film X may be provided with a separator (not shown) on the film 10 side at least in a form of covering the film 10. When the film 10 is smaller than the pressure-sensitive adhesive layer 22 of the dicing tape 20 and there is an unbonded region of the film 10 in the pressure-sensitive adhesive layer 22, for example, the separator covers at least the film 10 and the pressure-sensitive adhesive layer 22. It may be provided in a form. The separator is an element for protecting the film 10 and the adhesive layer 22 from being exposed, and is peeled off from the back surface protective film X integrated with the dicing tape when the dicing tape integrated back surface protective film X is used.

2 to 6 show an example of a semiconductor device manufacturing method in which the above-mentioned dicing tape integrated back surface protective film X is used.

In the present semiconductor device manufacturing method, first, as shown in FIGS. 2A and 2B, the wafer W is thinned by grinding (wafer thinning step). The grinding process can be performed using a grinding device equipped with a grinding wheel. The wafer W is a semiconductor wafer and has a first surface Wa and a second surface Wb. Various semiconductor elements (not shown) have already been built on the side of the first surface Wa of the wafer W, and the wiring structure and the like (not shown) required for the semiconductor element have already been formed on the first surface Wa. ing. The second surface Wb is a so-called back surface. In this step, after the wafer processing tape T1 having the adhesive surface T1a is bonded to the first surface Wa side of the wafer W, the wafer W is held in a state where the wafer W is held by the wafer processing tape T1 and the wafer W has a predetermined thickness. Up to this point, the second surface Wb is ground to obtain a thinned wafer 30.

Next, as shown in FIG. 3A, the wafer 30 held by the wafer processing tape T1 is attached to the film 10 of the dicing tape integrated back surface protective film X or the adhesive layer 12 thereof. After that, as shown in FIG. 3B, the wafer processing tape T1 is peeled off from the wafer 30.

Next, a heat treatment for thermosetting the adhesive layer 12 is performed (cure step). 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 carried out at 120 ° C. for 2 hours. In this step, the adhesive layer 12 is heat-cured to increase the adhesion between the film 10 of the dicing tape integrated back surface protective film X and the wafer 30, and the dicing tape integrated back surface protective film X or the film 10 is fixed to the wafer. The holding power is increased.

Next, the laser mark layer 11 of the film 10 in the back surface protective film X integrated with the dicing tape is irradiated with a laser from the side of the base material 21 of the dicing tape 20 to perform laser marking (laser marking step). By this laser marking, various information such as character information and graphic information is engraved on each semiconductor element that is later fragmented into a semiconductor chip. In this step, in one laser marking process, it is possible to collectively and efficiently perform laser marking on a large number of semiconductor elements in the wafer 30. Examples of the laser used in this step include a gas laser and a solid-state laser. Examples of the gas laser include a carbon dioxide gas laser (CO ₂ laser) and an excimer laser. Examples of the solid-state laser include an Nd: YAG laser.

Next, after the ring frame 41 is attached on the adhesive layer 22 of the back surface protective film X integrated with the dicing tape, cutting is performed by the dicing blade provided in the dicing device as shown in FIG. 4 (dicing step). ). In FIG. 4, the cutting portion is schematically represented by a thick line. In this step, the wafer 30 is fragmented into chips 31, and at the same time, the film 10 of the dicing tape integrated back surface protective film X is cut into small pieces of film 10'. As a result, a chip 31 with a film 10'for forming a protective film on the back surface of the chip, that is, a chip 31 with a film 10'is obtained.

When the pressure-sensitive adhesive layer 22 of the dicing tape 20 contains a radiation-curable pressure-sensitive adhesive, instead of the above-mentioned irradiation in the manufacturing process of the dicing tape-integrated back surface protective film X, a base is used after the above-mentioned dicing step. The pressure-sensitive adhesive layer 22 may be irradiated with radiation such as ultraviolet rays from the side of the material 21. The irradiation amount is, for example, 50 to 500 mJ / cm ² . In the dicing tape integrated back surface protective film X, the region where the pressure-sensitive adhesive layer 22 is irradiated as a measure for reducing the adhesive strength (irradiation region R shown in FIG. 1) is, for example, in the film 10 bonding region in the pressure-sensitive adhesive layer 22. This is the area excluding the peripheral part.

Next, a cleaning step of cleaning the chip 31 side of the dicing tape 20 with the chip 31 with the film 10'using a cleaning liquid such as water, and an expanding step for widening the separation distance between the chips 31 with the film 10'are performed. After passing through as necessary, as shown in FIG. 5, the chip 31 with the film 10'is picked up from the dicing tape 20 (pickup step). For example, after holding the dicing tape integrated back surface protective film X with the ring frame 41 on the holder 42 of the apparatus, the pick-up mechanism of the chip 31 with the film 10'to be picked up is on the lower side in the drawing of the dicing tape 20. The pin member 43 of the above is raised and pushed up through the dicing tape 20, and then sucked and held by the suction jig 44. In the pick-up step, the push-up speed of the pin member 43 is, for example, 1 to 100 mm / sec, and the push-up amount of the pin member 43 is, for example, 50 to 3000 μm.

Next, as shown in FIG. 6, the chip 31 with the film 10'is flip-chip mounted on the mounting substrate 51. Examples of the mounting board 51 include a lead frame, a TAB (Tape Automated Bonding) film, and a wiring board. The chip 31 is electrically connected to the mounting substrate 51 via a bump 52. Specifically, the electrode pad (not shown) of the chip 31 on the circuit forming surface side and the terminal portion (not shown) of the mounting substrate 51 are electrically connected via the bump 52. The bump 52 is, for example, a solder bump. Further, a thermosetting underfill agent 53 is interposed between the chip 31 and the mounting substrate 51.

As described above, the semiconductor device can be manufactured by using the back surface protective film X integrated with the dicing tape.

In the dicing tape integrated back surface protective film X of the present embodiment, as described above, the laser mark layer 11 is a cured thermosetting layer, and the adhesive layer 12 has thermosetting property. In such a configuration, the adhesive layer 12 for forming the work-attached surface is thermoset by heat treatment at 120 ° C. for 2 hours, while the laser mark layer 11 that adheres to the dicing tape 20 is substantially. It is suitable for realizing a laminated structure that does not cure by heat in the film 10.

As described above, the film 10 in the dicing tape-integrated back surface protective film X has a width of 10 mm and a thickness of, for example, 25 μm when heat-treated at 120 ° C. for 2 hours (back surface protective film sample piece). The tensile storage elastic modulus at 80 ° C. measured under the conditions of an initial chuck distance of 22.5 mm, a frequency of 1 Hz and a heating rate of 10 ° C./min is 0.5 GPa or more, preferably 0.75 GPa or more, more preferably. Is 1 GPa or more. Such a configuration is suitable for securing the fixing holding force against the wafer required in the dicing process in the dicing tape integrated back surface protective film X. The configuration in which such a relatively high tensile storage elastic modulus can be obtained by heat-treating the film 10 at 120 ° C. for 2 hours is concerned after the film 10 in the dicing tape-integrated back surface protective film X is bonded to a semiconductor wafer. It is suitable for heat-curing the film 10 to realize a high holding force for fixing to a wafer. The dicing tape-integrated back surface protective film X having the configuration suitable for securing the holding force for fixing to the wafer required in the dicing process is used in blade dicing for separating the wafer 30 into chips 31 on the dicing tape 20. It is suitable for suppressing cracks on the side surface of the chip 31. Then, the adhesive layer 12 is thermoset by the configuration suitable for securing the fixing holding force to the wafer required in the dicing step and the heat treatment at 120 ° C. for 2 hours, while the laser mark layer 11 is substantially. The dicing tape-integrated back surface protective film X, which also has the above-mentioned configuration suitable for realizing a laminated structure that does not cure by heat, is subjected to heat treatment on the film 10 while suppressing an increase in the adhesive force against the dicing tape. Suitable for securing wafer fixing holding force. The configuration that suppresses the increase in the adhesion to the dicing tape during the heat treatment for ensuring the fixing and holding force against the wafer in the film 10 contributes to appropriately picking up the chip 31 with the film 10'from the dicing tape 20 in the pick-up process. ..

As described above, the distance between the film 10 (the film 10 before the heat treatment) in the dicing tape integrated back surface protective film X and the adhesive layer 22 of the dicing tape 20 is 23 ° C., a peeling angle of 180 °, and a tensile speed of 300 mm. In the peeling test under the condition of / minute, the adhesive strength can be 0.1 N / 20 mm or less, preferably 0.08 N / 20 mm or less, more preferably 0.06 N / 20 mm or less. The structure of the film 10 and the pressure-sensitive adhesive layer 22 and the heat treatment at 120 ° C. for 2 hours causes the adhesive layer 12 to be thermally cured, while the laser mark layer 11 is substantially. The dicing tape-integrated back surface protective film X, which also has the above-mentioned configuration suitable for realizing a laminated structure that does not cure by heat, is anti-diced during heat treatment for ensuring the fixing holding force against the wafer for the film 10. It is suitable for realizing good pick-up of the chip 31 with the film 10'from the dicing tape 20 in the pick-up process after suppressing the increase in the tape adhesion force.

As described above, the back surface protective film X integrated with the dicing tape suppresses cracks on the side surface of the chip 31 in blade dicing for separating the wafer 30 into the chip 31 on the dicing tape 20, and dicing. It is suitable for realizing a good pickup of the chip 31 with the film 10'from the tape 20.

As described above, the film 10 of the back surface protective film X integrated with the dicing tape has a calorific value in the range of 50 to 200 ° C., preferably 40 J / g, in the differential scanning calorimetry at a heating rate of 10 ° C./min. Below, it is more preferably 35 J / g or less, and more preferably 30 J / g or less. Such a configuration is for ensuring the fixing holding force against the wafer in the film 10 in which the laser mark layer 11 is a cured thermosetting layer and the adhesive layer 12 is an uncured thermosetting layer. It is suitable for suppressing an increase in the adhesive force against the dicing tape during the heat treatment, and therefore contributes to realizing good pick-up of the chip 31 with the film 10'in the pick-up process.

In the dicing tape integrated back surface protective film X, as described above, the value of the ratio of the thickness of the laser mark layer 11 to the thickness of the adhesive layer 12 is preferably 1 or more, more preferably 1.5 or more. More preferably, it is 2 or more. In the film 10 in which the laser mark layer 11 is a cured thermosetting layer and the adhesive layer 12 is an uncured thermosetting layer, the thickness of the cured laser mark layer 11 in the total thickness of the film. The larger the ratio of, the more it is possible to suppress the occurrence of cracks on the side surface of the chip 31 in blade dicing.

[Example 1]
<Making a backside protective film>
In the production of the back surface protective film of the dicing tape integrated back surface protective film, first, the first resin film that forms the laser mark layer (LM layer) and the second resin film that forms the adhesive layer (AH layer) are formed. A resin film and a resin film were individually prepared.

In the production of the first resin film, first, 100 parts by mass of acrylic resin (trade name "Taisan Resin SG-P3", weight average molecular weight is 850,000, glass transition temperature Tg is 12 ° C., manufactured by Nagase ChemteX Corporation) is used. , Epoxy resin E ₁ (trade name "KI-3000-4", manufactured by Toto Kasei Co., Ltd.) 50 parts by mass, epoxy resin E ₂ (trade name "JER YL980", manufactured by Mitsubishi Chemical Co., Ltd.) 20 parts by mass, 75 parts by mass of phenol resin (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) and 175 mass of filler (trade name "SO-25R", silica, average particle size 0.5 μm, manufactured by Admatex Co., Ltd.) 15 parts by mass of black dye (trade name "OIL BLACK BS", manufactured by Orient _{Chemical Industry Co., Ltd.) and 20 parts by mass of thermal curing catalyst Z 1} (trade name "Curesol 2PZ", manufactured by Shikoku Kasei Kogyo Co., Ltd.) Was added to and mixed with methyl ethyl ketone to obtain a resin composition having a solid content concentration of 30% by mass. Next, the resin composition was applied onto the silicone release-treated surface of the PET separator (thickness 50 μm) having the silicone release-treated surface using an applicator to form a resin composition layer. Next, this composition layer is heated at 130 ° C. for 2 minutes to dry and thermoset, and a first resin film having a thickness of 18 μm (a laser mark layer which is a cured thermosetting layer) is formed on a PET separator. A different film) was produced.

In the production of the second resin film, first, 100 parts by mass of acrylic resin (trade name "Taisan Resin SG-P3", manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name "KI-3000-4") are produced. , Toto Kasei Co., Ltd.) 50 parts by mass, epoxy resin E ₂ (trade name "JER YL980", manufactured by Mitsubishi Chemical Co., Ltd.) 20 parts by mass, phenol resin (trade name "MEH7851-SS", Meiwa Kasei Co., Ltd.) 75 parts by mass of filler (trade name "SO-25R", manufactured by Admatex Co., Ltd.) and 15 parts by mass of black dye (trade name "OIL BLACK BS", manufactured by Orient Chemical Industry Co., Ltd.) And 7 parts by mass of a thermosetting catalyst Z ₂ (trade name “Curesol 2PHZ”, manufactured by Shikoku Kasei Kogyo Co., Ltd.) were added to methyl ethyl ketone and mixed to obtain a resin composition having a solid content concentration of 36% by mass. Next, the resin composition was applied onto the silicone release-treated surface of the PET separator (thickness 50 μm) having the silicone release-treated surface using an applicator to form a resin composition layer. Next, this composition layer is heated at 130 ° C. for 2 minutes to be dried to form a 7 μm-thick second resin film (an adhesive layer which is a thermosetting layer in an uncured state) on a PET separator. Film) was produced.

The first resin film on the PET separator and the second resin film on the PET separator prepared as described above were bonded together using a laminator. Specifically, the exposed surfaces of the first and second resin films were bonded to each other under the conditions of a temperature of 100 ° C. and a pressure of 0.85 MPa. As described above, the back surface protective film of Example 1 was produced. The compositions of the laser mark layer (LM layer) and the adhesive layer (AH layer) in Example 1 and each of the Examples and Comparative Examples described later are listed in Table 1 (in Table 1, each numerical unit representing the composition of each layer). Is the relative "parts of mass" within the layer).

<Making dicing tape>
In a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer, 100 parts by mass of 2-ethylhexyl acrylate, 19 parts by mass of 2-hydroxyethyl acrylate, and peroxidation as a polymerization initiator. A mixture containing 0.4 parts by mass of benzoyl and 80 parts by mass of toluene as a polymerization solvent was stirred at 60 ° C. for 10 hours in a nitrogen atmosphere (polymerization reaction). As a result, a polymer solution containing the _{acrylic polymer P 1 was obtained.} Next, a mixture containing the polymer solution containing the acrylic polymer P ₁ , 2-methacryloyloxyethyl isocyanate (MOI), and dibutyltin dilaurylate as an addition reaction catalyst was mixed at 50 ° C. for 60 hours under an air atmosphere. Stirred in (addition reaction). 0 in the reaction solution, the amount of the MOI is 12 parts by weight with respect to the acrylic polymer P ₁ 100 parts by weight, the amount of dibutyltin dilaurate, relative to the acrylic polymer P ₁ 100 parts by weight. It is 06 parts by mass. By this addition reaction, a polymer solution containing _{an acrylic polymer P 2} having a methacrylate group in the side chain was obtained. Next, in the polymer solution, ₂ parts by mass of a polyisocyanate compound (trade name "Coronate L", manufactured by Toso Co., Ltd.) and 2 parts by mass of a photopolymerization initiator (2 parts by mass) with respect to 100 parts by mass of the acrylic polymer P 2 The trade name "Irgacure 369" (manufactured by BASF) and toluene were added and mixed to obtain a pressure-sensitive adhesive composition having a solid content concentration of 28% by mass. Next, the pressure-sensitive adhesive composition was applied onto the silicone release-treated surface of the PET separator (thickness 50 μm) having the silicone release-treated surface using an applicator to form a pressure-sensitive adhesive composition layer. .. Next, this composition layer was heat-dried at 120 ° C. for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 30 μm on the PET separator. Next, using a laminator, a polypropylene film (trade name "SC040PP1-BL", thickness 40 μm, manufactured by Kurabo Industries Ltd.) as a base material was attached to the exposed surface of the pressure-sensitive adhesive layer at room temperature. The laminate was then stored at 23 ° C. for 72 hours. The dicing tape was produced as described above.

<Manufacturing of backside protective film with integrated dicing tape>
The above-mentioned back surface protective film of Example 1 with a PET separator was punched into a circle having a diameter of 330 mm. Next, after peeling the PET separator from the back surface protective film and peeling the PET separator from the dicing tape described above, the pressure-sensitive adhesive layer exposed on the dicing tape and the surface exposed by peeling the PET separator on the dicing film are separated. , Laminated using a hand roller. Next, the dicing tape thus bonded to the back surface protective film was punched into a circle having a diameter of 390 mm so that the center of the dicing tape and the center of the back surface protective film coincided with each other. As described above, the dicing tape integrated back surface protective film of Example 1 having a laminated structure of the dicing tape and the back surface protective film was produced. The back surface protective film in the dicing tape integrated back surface protective film of Example 1 has a laminated structure of a cured laser mark layer (LM layer) and an uncured adhesive layer (AH layer).

[Example 2]
In the production of the first resin film, _{the blending amount of the epoxy resin E 1} is 137 parts by mass instead of 50 parts by mass, the blending amount of the epoxy resin E ₂ is 59 parts by mass instead of 20 parts by mass, and the phenol resin is blended. The amount was changed to 205 parts by mass instead of 75 parts by mass, the amount of the filler was changed to 355 parts by mass instead of 175 parts by mass, and the amount of black dye was changed to 30 parts by mass instead of 15 parts by mass. The compounding amount of Z ₁ was 43 parts by mass instead of 20 parts by mass, and in the production of the second resin film, _{the compounding amount of epoxy resin E 1} was 137 parts by mass instead of 50 parts by mass, and the epoxy resin was prepared. The blending amount of E ₂ was 59 parts by mass instead of 20 parts by mass, the blending amount of phenol resin was 205 parts by mass instead of 75 parts by mass, and the blending amount of filler was 355 parts by mass instead of 175 parts by mass. The dying tape integrated type of Example 1 except that the amount of the black dye was changed to 30 parts by mass instead of 15 parts and the amount of the heat curing catalyst Z ₂ was changed to 13 parts by mass instead of 7 parts by mass. In the same manner as the back surface protective film, the back surface protective film integrated with the dicing tape of Example 2 was produced. The back surface protective film in the dicing tape integrated back surface protective film of Example 2 has a laminated structure of a cured laser mark layer (LM layer) and an uncured adhesive layer (AH layer).

[Example 3]
In the production of the first resin film, _{the compounding amount of the epoxy resin E 1} is 200 parts by mass instead of 50 parts by mass, the compounding amount of the epoxy resin E ₂ is 80 parts by mass instead of 20 parts by mass, and the phenol resin is compounded. The amount was 290 parts by mass instead of 75 parts by mass, the blending amount of the filler was 470 parts by mass instead of 175 parts by mass, and the blending amount of the black dye was 40 parts by mass instead of 15 parts by mass. The compounding amount of Z ₁ was 57 parts by mass instead of 20 parts by mass, and in the production of the second resin film, _{the compounding amount of epoxy resin E 1} was 200 parts by mass instead of 50 parts by mass, and the epoxy resin was prepared. The blending amount of E ₂ was 80 parts by mass instead of 20 parts by mass, the blending amount of phenol resin was 290 parts by mass instead of 75 parts by mass, and the blending amount of filler was 470 parts by mass instead of 175 parts by mass. The dicing tape integrated type of Example 1 except that the blending amount of the black dye was 40 parts by mass instead of 15 parts by mass and the blending amount of the heat curing catalyst Z ₂ was 17 parts by mass instead of 7 parts by mass. In the same manner as the back surface protective film, the back surface protective film integrated with the dicing tape of Example 3 was produced. The back surface protective film in the dicing tape integrated back surface protective film of Example 3 has a laminated structure of a cured laser mark layer (LM layer) and an uncured adhesive layer (AH layer).

[Comparative Example 1]
100 parts by mass of acrylic resin (trade name "Taisan Resin SG-P3", manufactured by Nagase ChemteX _{Corporation), 70 parts by mass of epoxy resin E 3} (trade name "EPPN-501HY", manufactured by Nippon Kayaku Co., Ltd.), 80 parts by mass of phenol resin (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.), 175 parts by mass of filler (trade name "SO-25R", manufactured by Admatex Co., Ltd.), and black dye (trade name """OIL BLACK BS", manufactured by Orient Chemical Industry Co., Ltd.) was added to methyl ethyl ketone and mixed with 15 parts by mass to obtain a resin composition having a solid content concentration of 30% by mass. Next, the resin composition was applied onto the silicone release-treated surface of the PET separator (thickness 50 μm) having the silicone release-treated surface using an applicator to form a resin composition layer. Next, this composition layer was heated at 130 ° C. for 2 minutes and dried to prepare a back surface protective film having a thickness of 25 μm on a PET separator. Then, the dicing tape of Comparative Example 1 was used in the same manner as the dicing tape integrated back surface protective film of Example 1 except that the back surface protective film of Comparative Example 1 was used instead of the above-mentioned back surface protective film of Example 1. An integrated back surface protective film was produced. The back surface protective film in the back surface protective film integrated with the dicing tape of Comparative Example 1 is composed of a single thermoplastic layer.

[Comparative Example 2]
100 parts by mass of acrylic resin (trade name "Taisan Resin SG-P3", manufactured by Nagase ChemteX Corporation) and 50 parts by mass of epoxy resin E ₁ (trade name "KI-3000-4", manufactured by Toto Kasei Co., Ltd.) , Epoxy resin E ₂ (trade name "JER YL980", manufactured by Mitsubishi Chemical Co., Ltd.) 20 parts by mass, phenol resin (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) 75 parts by mass, filler (trade name) "SO-25R", manufactured by Admatex Co., Ltd., 175 parts by mass, black dye (trade name "OIL BLACK BS", manufactured by Orient Chemical Industry Co., Ltd.), 15 parts by mass, and thermosetting catalyst Z ₂ (trade name "" 7 parts by mass of "Curesol 2PHZ" (manufactured by Shikoku Kasei Kogyo Co., Ltd.) was added to methyl ethyl ketone and mixed to obtain a resin composition having a solid content concentration of 30% by mass. Next, the resin composition was applied onto the silicone release-treated surface of the PET separator (thickness 50 μm) having the silicone release-treated surface using an applicator to form a resin composition layer. Next, this composition layer was heated at 130 ° C. for 2 minutes and dried to prepare a back surface protective film having a thickness of 25 μm on a PET separator. Then, the dicing tape of Comparative Example 2 was used in the same manner as the dicing tape integrated back surface protective film of Example 1 except that the back surface protective film of Comparative Example 2 was used instead of the above-mentioned back surface protective film of Example 1. An integrated back surface protective film was produced. The back surface protective film in the dicing tape integrated back surface protective film of Comparative Example 2 is composed of a single thermosetting layer in an uncured state.

[Comparative Example 3]
In the production of the second resin film, _{70 parts by mass of epoxy resin E 3} (trade name "EPPN-501HY", manufactured by Nippon Kayaku Co., Ltd.) was used instead of 50 parts by mass of _{epoxy resin E 1} and 20 parts by mass of _{epoxy resin E 2.} Except for the fact that the phenol resin was used, the amount of the phenol resin was 80 parts by mass instead of 75 parts by mass, and the thermosetting catalyst Z ₂ was not used, the back surface protective film integrated with the dying tape of Example 1 was used. In the same manner, the back surface protective film integrated with the dying tape of Comparative Example 3 was produced. The back surface protective film in the dicing tape integrated back surface protective film of Comparative Example 3 has a laminated structure of a cured laser mark layer (LM layer) and an adhesive layer (AH layer) which is a thermoplastic layer.

[Tension storage elastic modulus]
Dynamic viscoelasticity measurement performed by using a dynamic viscoelasticity measuring device (trade name "Solid Analyzer RS GII", manufactured by Leometric Co., Ltd.) for the above-mentioned back surface protective films in Examples 1 to 3 and Comparative Examples 1 to 3. The tensile storage elastic modulus (GPa) at 80 ° C. was determined based on the above. From each of the back surface protective films of Examples 1 to 3 and Comparative Example 2, after heat treatment at 120 ° C. for 2 hours, a sample piece having a size of 10 mm in width × 30 mm in length was cut out. A sample piece having a width of 10 mm and a length of 30 mm was cut out from each of the back surface protective films of Comparative Examples 1 and 3 without heat treatment. In the measurement, the initial distance between the chucks for holding the sample piece is 22.5 mm, the measurement mode is the tension mode, the measurement environment is a nitrogen atmosphere, the measurement temperature range is 0 ° C to 100 ° C, and the frequency is set. The temperature was set to 1 Hz, and the heating rate was set to 10 ° C./min. Table 1 shows the measurement results of the tensile storage elastic modulus (GPa).

<Adhesive strength between the back surface protective film and the dicing tape adhesive layer>
For each dicing tape integrated back surface protective film of Examples 1 to 3 and Comparative Examples 1 to 3, the adhesive strength between the back surface protective film and the dicing tape adhesive layer was examined. The sample piece preparation method and the adhesive strength measurement method for that purpose are as follows.

In the preparation of the sample piece, first, a single-sided adhesive tape (trade name "BT-315", manufactured by Nitto Denko KK) was attached to the back surface protective film side of the dicing tape integrated back surface protective film. This bonding is performed after the back surface protective films integrated with the dicing tapes of Examples 1 to 3 and Comparative Example 2 are heat-treated at 120 ° C. for 2 hours, and the dicing tape integrated type of Comparative Examples 1 and 3 is attached. The back surface protective film was not heat-treated. Next, the adhesive layer of the dicing tape of the dicing tape integrated back surface protective film with a single-sided adhesive tape on the back surface protective film side is irradiated with ultraviolet rays of ^{300 mJ / cm 2 through the base material to form the adhesive layer.} After curing, a sample piece having a size of 20 mm in width and 100 mm in length was cut out from the laminate. Then, using a tensile tester (trade name "Autograph AGS-J", manufactured by Shimadzu Corporation), a peel test is performed on the sample piece under the conditions of 23 ° C, a peeling angle of 180 °, and a tensile speed of 300 mm / min. Then, the force required for peeling between the back surface protective film and the dicing tape adhesive layer in the dicing tape integrated back surface protective film was measured. Then, the average value of the peeling force at the central portion of 60 mm in the length direction of the sample piece was taken as the adhesive force (N / 20 mm) related to the measurement. The results are listed in Table 1. Regarding the pick-up property of the chip with a film from the dicing tape adhesive layer, when the adhesive strength is 0.1 N / 20 mm or less, it is evaluated as good (○), and when it is larger than 0.1 N / 20 mm, it is defective. It was evaluated as (x). This evaluation is also listed in Table 1.

<DSC calorific value>
The back surface protective film of each dicing tape integrated back surface protective film of Examples 1 to 3 and Comparative Examples 1 to 3 is carried out using a differential scanning calorimeter (trade name “DSC Q2000”, manufactured by TA Instruments). The calorific value in the range of 50 to 200 ° C. in the differential scanning calorimetry was examined. The sample piece (diameter 3 mm, mass 10 mg) used for the measurement is cut out from the back surface protective film peeled off from the dicing tape integrated back surface protective film. In the measurement, the measurement environment was set to a nitrogen atmosphere, the measurement temperature range was set to −20 ° C. to 300 ° C., and the temperature rising rate was set to 10 ° C./min. Then, with respect to the exothermic peak appearing in the range of 50 to 200 ° C. in the DSC chart obtained by the measurement, the integrated value of the calorific value above the baseline at 50 to 200 ° C. of the chart is obtained as the calorific value (J / g). rice field. The results are listed in Table 1.

<Crack suppression on the side of the chip in blade dicing>
The presence or absence and degree of cracks on the side surface of the chip were investigated when blade dicing of the semiconductor wafer was performed using the back surface protective films integrated with the dicing tapes of Examples 1 to 3 and Comparative Examples 1 to 3. Specifically, it is as follows.

First, a silicon mirror wafer (diameter 8 inches, thickness 200 μm) having been subjected to back surface polishing treatment was attached to the back surface protective film of the dicing tape integrated back surface protective film. This bonding was performed by roll crimping at a temperature of 75 ° C., a pressure of 0.15 MPa, and a bonding speed of 10 mm / sec. After bonding, the dicing tape-integrated back surface protective films of Examples 1 to 3 and Comparative Example 2 were heat-treated at 120 ° C. for 2 hours (dicing tape-integrated back surface protection of Comparative Examples 1 and 3). In the case of film, heat treatment was not performed after bonding). Next, the wafer on the back surface protective film integrated with dicing tape is cut into chips with a size of 2 mm x 2 mm by blade dicing using a dicing device (trade name "DFD-6361", manufactured by DISCO Corporation). Diced. In this blade dicing, first, a Z1 blade (trade name "203O-SE 27HCDD", manufactured by DISCO Corporation) cuts the wafer from the wafer surface to a depth of half its thickness under the condition of a blade rotation speed of 40,000 rpm, and then cuts the wafer to a depth of half its thickness. The dicing tape adhesive layer was cut to a depth of half its thickness by a Z2 blade (trade name "203O-SE 27HCBB", manufactured by DISCO Corporation) under the condition of a blade rotation speed of 45,000 rpm. Each semiconductor chip thus separated is accompanied by a small piece of back surface protective film derived from the back surface protective film of the dicing tape integrated back surface protective film. ^{Next, the adhesive layer is irradiated with ultraviolet rays having an integrated irradiation light amount of 300 mJ / cm 2} from the side of the base material of the dicing tape in the dicing tape integrated back surface protective film to cure the adhesive layer, and then from the dicing tape. I picked up a chip with a film. Then, of the four sides of the picked-up chip with film, the side surface as the last formed cut surface was observed using a microscope (trade name "Digital Microscope VHX500", manufactured by KEYENCE CORPORATION). The depth of the crack formation position was measured. Regarding the crack suppression property in blade dicing, the case where the depth of the crack formation position from the interface between the chip and the back surface protective film in close contact with the chip is less than 15% of the total thickness of the chip is excellent (◎). Evaluate, and evaluate as good (○) when it is 15% or more and less than 30% of the total thickness of the chip, and evaluate as acceptable (△) when it is 30% or more and less than 50% of the total thickness of the chip. , When it was 50% or more of the total thickness of the chip, it was evaluated as impossible (x). The results are listed in Table 1.

[evaluation]
The back surface protective film in the back surface protective film integrated with the dicing tape of Examples 1 to 3 has a tensile storage elasticity at 80 ° C. measured by the above-mentioned dynamic viscoelasticity measurement when heat-treated at 120 ° C. for 2 hours. The rate was 0.5 GPa or more. In the dicing tape integrated back surface protective film of Examples 1 to 3, the adhesive force between the back surface protective film and the dicing tape pressure-sensitive adhesive layer was 0.1 N / 20 mm or less in the above-mentioned peeling test. The back surface protective film in the dicing tape integrated back surface protective film of Examples 1 to 3 had a calorific value of 40 J / g or less in the range of 50 to 200 ° C. in the above-mentioned differential scanning calorimetry. According to the dicing tape integrated back surface protective film of Examples 1 to 3, it is possible to suppress cracks on the side surface of the chip during blade dicing, and a good pickup of the chip with the back surface protective film from the dicing tape. Can be realized.

X Dicing tape integrated backside protective film 10,10'film (backside protective film)
11 Laser mark layer 12 Adhesive layer 20 Dicing tape 21 Base material 22 Adhesive layer W, 30 Wafer 31 Chip

Claims (3)

A dicing tape having a laminated structure including a base material and an adhesive layer,
A back surface protective film having a laminated structure including a laser mark layer and an adhesive layer and having a peelable adhesion to the adhesive layer of the dicing tape on the side of the laser mark layer is provided.
The back surface protective film that has been heat-treated at 120 ° C. for 2 hours is measured for a back surface protective film sample piece having a width of 10 mm under the conditions of an initial chuck distance of 22.5 mm, a frequency of 1 Hz, and a heating rate of 10 ° C./min. The tensile storage elastic modulus at ° C. is 0.5 GPa or more,
Between the back surface protective film and the pressure-sensitive adhesive layer, 23 ° C., in a peeling test at a peeling angle of 180 ° and a tensile speed 300 mm / min condition, Ri will show the following adhesive strength 0.1 N / 20 mm,
The back surface protective film is a dicing tape integrated back surface protective film having a calorific value of 40 J / g or less in the range of 50 to 200 ° C. in differential scanning calorimetry at a temperature rise rate of 10 ° C./min. The dicing tape-integrated back surface protective film according to claim 1, wherein the laser mark layer is a cured thermosetting layer, and the adhesive layer has thermosetting properties. The dicing tape integrated back surface protective film according to claim 1 or 2 , wherein the value of the ratio of the thickness of the laser mark layer to the thickness of the adhesive layer is 1 or more.

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