Dicing Die Bond Film

Abstract

To provide a dicing die-bonding film capable of suppressing the occurrence of cracks in an adhesive layer during an expand process.SOLUTION: A dicing die-bonding film includes a dicing tape in which an adhesive layer is laminated on a base material layer, and a die-bonding layer laminated on the adhesive layer of the dicing tape. The adhesive layer contains an acrylic polymer, and the acrylic polymer contains 15 mol% or more of a structural unit of an alkyl (meth)acrylate having an alkyl group with a carbon number of 9 or more. The shear storage modulus of the adhesive layer at a temperature of -15°C is 10 MPa or less, and the glass transition temperature of the acrylic polymer calculated using the FOX formula is -47°C or above and 5°C or below.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a dicing die bond film.

Background Art

[0002] Conventionally, in the manufacture of semiconductor devices, it is known to use a dicing die bond film to obtain semiconductor chips for die bonding (for example, Patent Document 1). The dicing die bond film includes a dicing tape having an adhesive layer laminated on a base material layer, and a die bond layer laminated removably on the adhesive layer of the dicing tape.

[0003] And, as a method of obtaining a semiconductor chip (die) for die bonding using the dicing die bond film, a half-cut step of forming grooves in a semiconductor wafer to process the semiconductor wafer into chips (dies) by a dicing process, a back grinding step of grinding the semiconductor wafer after the half-cut step to reduce the thickness, a mounting step of attaching one surface (for example, the surface opposite to the circuit surface) of the semiconductor wafer after the back grinding step to the die bond layer to fix the semiconductor wafer to the dicing tape, an expand step of widening the interval between semiconductor chips, a kerf maintaining step of maintaining the interval between semiconductor chips, and a pickup step of peeling between the die bond layer and the adhesive layer and taking out the semiconductor chips with the die bond layer attached, are known to be adopted. And, in the pickup step, the semiconductor chip taken out in a state of being attached to the die bond layer (hereinafter, also referred to as a semiconductor chip with a die bond layer) is adhered to a wiring board as an adherend.

[0004] In the method for manufacturing a semiconductor device as described above, in the expansion step, usually, the dicing tape is stretched at a temperature within the range of -20°C to 5°C to cut the die bond layer, and after obtaining a plurality of diced die bond layers (cool expansion), at a temperature higher than this (for example, 23 ± 2°C), the distance between adjacent diced die bond layers is further widened (room temperature expansion).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] By the way, in the expansion step, when cool expansion is being carried out, the adhesive layer may crack. Thus, if the adhesive layer cracks when cool expansion is being carried out, when the distance between the diced die bond layers is further widened by room temperature expansion, there is a risk that the distance between the die bond layers facing each other across the crack will be wider than the distance between the die bond layers arranged on the adhesive layer where no crack has occurred. That is, after the expansion step, there is a risk that the non-uniformity of the distance between the diced die bond layers will increase. Thus, when the non-uniformity of the distance between the diced die bond layers increases, it becomes difficult to pick up the semiconductor chip with a die bond layer in the pick-up step, which is not preferable. However, it is hard to say that sufficient consideration has been given to suppressing the occurrence of cracks in the adhesive layer in the expansion step.

[0007] Therefore, an object of the present invention is to provide a dicing die bond film capable of suppressing the occurrence of cracks in the adhesive layer during the expansion process.

Means for Solving the Problems

[0008] As a result of intensive studies by the present inventors, the acrylic polymer contained in the adhesive layer is made to contain 15 mol% or more of a structural unit of (meth)alkyl acrylate having an alkyl group with 9 or more carbon atoms, and the shear storage modulus of the adhesive layer at a temperature of -15°C is set to 10 MPa or more. Further, by making the glass transition temperature of the acrylic polymer calculated using the FOX equation satisfy -47°C or more and 5°C or less, it has been found that the occurrence of cracks in the adhesive layer can be suppressed during the expansion process. And the present invention has been conceived.

[0009] That is, the dicing die bond film according to the present invention is a dicing tape in which an adhesive layer is laminated on a base material layer, and a die bond layer laminated on the adhesive layer of the dicing tape, and the adhesive layer contains an acrylic polymer, the acrylic polymer contains 15 mol% or more of a structural unit of alkyl (meth)acrylate having an alkyl group with 9 or more carbon atoms, the shear storage modulus of the adhesive layer at a temperature of -15°C is 10 MPa The following or more, and the glass transition temperature of the acrylic polymer calculated using the FOX equation is -47°C or more and 5°C or less.

[0010] According to such a configuration, the occurrence of cracks in the adhesive layer can be suppressed during the expansion process. Thereby, in the pickup process, it becomes easier to pick up the semiconductor chip with the die bond layer.

[0011] In the dicing die bond film, It is preferable that the thickness of the dicing tape is 50 μm or more and 250 μm or less.

[0012] According to such a configuration, in the expansion step, it is possible to further suppress the occurrence of cracks in the adhesive layer. As a result, in the pickup step, it becomes easier to pick up the semiconductor chip with the die bond layer.

[0013] In the dicing die bond film, It is preferable that the 25% tensile strength of the dicing tape is 2 N / 10 mm or more and 50 N / 10 mm or less.

[0014] According to such a configuration, in the expansion step, it is possible to further suppress the occurrence of cracks in the adhesive layer. As a result, in the pickup step, it becomes easier to pick up the semiconductor chip with the die bond layer.

[0015] In the dicing die bond film, It is preferable that the 180° peel strength between the base material layer and the adhesive layer is 1.0 N / 20 mm or more at room temperature.

[0016] According to such a configuration, in the expansion step, it is possible to further suppress the occurrence of cracks in the adhesive layer. As a result, in the pickup step, it becomes easier to pick up the semiconductor chip with the die bond layer.

[0017] In the dicing die bond film, The acrylic polymer includes a structural unit of an alkyl (meth)acrylate having an alkyl group with 9 or more carbon atoms and a structural unit of a hydroxyl group-containing (meth)acrylate. It is preferable that the hydroxyl group-containing (meth)acrylate is contained in less than 40 mol%.

[0018] According to such a configuration, in the expand process, it is possible to further suppress the occurrence of cracks in the adhesive layer. As a result, in the pick-up process, it becomes easier to pick up the semiconductor chip with the die bond layer.

[0019] In the dicing die bond film, it is preferable that when the dicing tape is stretched by 200% at a tensile speed of 1000 mm / min at a temperature of -15°C, no cracks occur in the adhesive layer.

[0020] According to such a configuration, in the expand process, it is possible to further suppress the occurrence of cracks in the adhesive layer. As a result, in the pick-up process, it becomes easier to pick up the semiconductor chip with the die bond layer.

[0021] In the dicing die bond film, it is preferably used for dicing a semiconductor wafer.

Advantages of the Invention

[0022] According to the present invention, it is possible to provide a dicing die bond film capable of suppressing the occurrence of cracks in the adhesive layer in the expand process.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2A

Figure 2B

Figure 2C

Figure 2D

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 4C

Figure 5A

Figure 5B

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0024] Hereinafter, an embodiment of the present invention will be described.

[0025] [Dicing Die Bond Film] As shown in FIG. 1, the dicing die bond film 20 according to the present embodiment includes a dicing tape 10 in which an adhesive layer 2 is laminated on a base material layer 1, and a die bond layer 3 laminated on the adhesive layer 2 of the dicing tape 10. In the dicing die bond film 20, a semiconductor wafer is attached onto the die bond layer 3. In the dicing of the semiconductor wafer using the dicing die bond film 20, the die bond layer 3 is diced together with the semiconductor wafer. The die bond layer 3 is diced into a size corresponding to the size of a plurality of individual semiconductor chips. Thereby, semiconductor chips with the die bond layer 3 can be obtained.

[0026] In the dicing die bond film 20 according to the present embodiment, the adhesive layer 2 has adhesiveness and holds the die bond layer 3 by adhesion. In the dicing die bond film 20 according to the present embodiment, the adhesive layer 2 contains an acrylic polymer. In this specification, an acrylic polymer is a polymer containing (meth)acrylate monomer as a constitutional unit. (Meth)acrylate is a concept including methacrylate and acrylate. In the specification of the claims, The acrylic polymer may contain monomers other than (meth)acrylate monomers as constitutional units.

[0027] Preferably, the adhesive layer 2 contains 50% by mass or more of the acrylic polymer, more preferably 70% or more, and still more preferably 80% by mass or more. Also, preferably, the adhesive layer 2 contains 98% by mass or less of the acrylic polymer, more preferably 96% by mass or less.

[0028] The acrylic polymer is preferably an ultraviolet curable polymer having a polymerizable unsaturated bond (polymerizable acrylic polymer). Examples of the polymerizable polymer include polymers containing a polymerizable vinyl group or ethynyl group at the end of the main chain or side chain. Hereinafter, the polymerizable vinyl group or ethynyl group is collectively referred to as a polymerizable group. The polymerizable acrylic polymer can be obtained by copolymerizing a (meth)acrylate monomer and a polymerizable monomer.

[0029] In the acrylic polymer contained in the adhesive layer 2, the above structural units are 1 confirmed by NMR analysis such as 1H-NMR, 13 13C-NMR, pyrolysis GC / MS analysis, infrared spectroscopy (e.g., FTIR method), etc. The molar ratio of the above structural units in the acrylic polymer is usually calculated from the compounding amount (charged amount) when polymerizing the acrylic polymer.

[0030] In the present embodiment, the acrylic polymer contains 15 mol% or more of a structural unit of an alkyl (meth)acrylate having 9 or more carbon atoms. In the present embodiment, it is more preferable that the acrylic polymer contains 30 mol% or more of a structural unit of an alkyl (meth)acrylate having an alkyl group having 9 or more carbon atoms, and even more preferably 50 mol% or more. In the present embodiment, it is preferable that the acrylic polymer contains 80 mol% or less of a structural unit of an alkyl (meth)acrylate having an alkyl group having 9 or more carbon atoms.

[0031] The structural unit of the alkyl (meth)acrylate is derived from an alkyl (meth)acrylate monomer. That is, the structure of the alkyl (meth)acrylate monomer after polymerization is the above structural unit of the alkyl (meth)acrylate. In the structural unit of the alkyl (meth)acrylate, the alkyl may be a saturated hydrocarbon or an unsaturated hydrocarbon. For example, the alkyl is a linear saturated hydrocarbon, a branched saturated hydrocarbon, an alicyclic hydrocarbon, or an aromatic hydrocarbon. The alkyl is preferably a linear saturated hydrocarbon or a branched saturated hydrocarbon. Also, the alkyl may contain a polar group containing oxygen, nitrogen, or the like.

[0032] In this embodiment, the acrylic polymer may contain a structural unit of an alkyl (meth)acrylate having 8 or less carbon atoms.

[0033] Examples of the structural unit of the alkyl (meth)acrylate having 8 or less carbon atoms include structural units such as ethyl (meth)acrylate, butyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and isooctyl (meth)acrylate. Examples of the structural unit of the alkyl (meth)acrylate having 9 or more carbon atoms include structural units such as n-nonyl (meth)acrylate, iso(sec)-nonyl (meth)acrylate, tert-nonyl (meth)acrylate, isobornyl (meth)acrylate, n-decyl (meth)acrylate, iso(sec)-decyl (meth)acrylate, tert-decyl (meth)acrylate, n-undecyl (meth)acrylate, iso(sec)-undecyl (meth)acrylate, tert-undecyl (meth)acrylate, and lauryl (meth)acrylate.

[0034] In this embodiment, it is more preferable that the acrylic polymer contains an alkyl (meth)acrylate having an alkyl group with 12 or more carbon atoms as a structural unit. In this embodiment, it is preferable that the acrylic polymer contains 15 mol% or more of the structural unit of the alkyl (meth)acrylate having an alkyl group with 12 or more carbon atoms. In this embodiment, it is preferably that the acrylic polymer contains 18 mol% or more, and more preferably 20 mol% or more of the structural unit of the alkyl (meth)acrylate having an alkyl group with 12 or more carbon atoms. In this embodiment, it is preferably that the acrylic polymer contains 80 mol% or less, and more preferably 77 mol% or less of the structural unit of the alkyl (meth)acrylate having an alkyl group with 12 or more carbon atoms. Since the acrylic polymer is as described above, in the expansion step, it is possible to further suppress the occurrence of cracks in the adhesive layer 2. As a result, in the pickup step, it becomes easier to pick up the semiconductor chip with a die bond layer. Note that the upper limit of the number of carbon atoms in the structural unit of the alkyl (meth) acrylate is 18.

[0035] In the present embodiment, the acrylic polymer is preferably composed of a structural unit of an alkyl (meth) acrylate having 9 or more carbon atoms and a structural unit of a hydroxyl group-containing (meth) acrylate. In the acrylic polymer configured as described above, the structural unit of the hydroxyl group-containing (meth) acrylate is preferably contained in less than 40 mol%. In the acrylic polymer configured as described above, the structural unit of the hydroxyl group-containing (meth) acrylate is preferably contained in 10 mol% or more, and more preferably contained in 15 mol% or more. The structural unit of the alkyl (meth) acrylate is more preferably a structural unit of an alkyl (meth) acrylate having an alkyl group having 9 or more and 14 or less carbon atoms. The structural unit of the alkyl (meth) acrylate having an alkyl group having 9 or more and 14 or less carbon atoms is preferably contained in 15 mol% or more, more preferably contained in 18 mol% or more, and still more preferably contained in 20 mol% or more. The structural unit of the alkyl (meth) acrylate having an alkyl group having 9 or more and 14 or less carbon atoms is preferably contained in 85 mol% or less. Since the acrylic polymer is as described above, in the expansion step, it is possible to further suppress the occurrence of cracks in the adhesive layer 2. As a result, in the pickup step, it becomes easier to pick up the semiconductor chip with a die bond layer.

[0036] In the structural unit of the hydroxyl group-containing (meth)acrylate, the hydroxyl group contained in the structural unit readily reacts with an isocyanate group. Therefore, in the pressure-sensitive adhesive layer 2, as the acrylic polymer, one composed of the structural unit of the alkyl (meth)acrylate and the structural unit of the hydroxyl group-containing (meth)acrylate is contained, and an isocyanate compound is contained. Thus, the hydroxyl group in the structural unit of the hydroxyl group-containing (meth)acrylate reacts with the isocyanate group in the isocyanate compound, and the pressure-sensitive adhesive layer 2 can be appropriately cured.

[0037] The structural unit of the hydroxyl group-containing (meth)acrylate is derived from a hydroxyl group-containing (meth)acrylate monomer. That is, the structure of the hydroxyl group-containing (meth)acrylate monomer after polymerization is the structural unit of the hydroxyl group-containing (meth)acrylate.

[0038] The structural unit of the hydroxyl group-containing (meth)acrylate is preferably a structural unit of a hydroxyl group-containing C2-C4 alkyl (meth)acrylate. In the structural unit of the hydroxyl group-containing C2-C4 alkyl (meth)acrylate, the alkyl is usually a saturated hydrocarbon. For example, the alkyl is a linear saturated hydrocarbon or a branched-chain saturated hydrocarbon. Also, the alkyl preferably does not contain a polar group containing oxygen, nitrogen, or the like. In the structural unit of the hydrogen group-containing (meth)acrylate, although the hydroxyl group may be bonded to any carbon of the alkyl, it is preferably bonded to the terminal carbon of the alkyl.

[0039] Examples of the structural unit of the hydroxyl group-containing (meth)acrylate include structural units such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, or hydroxybutyl (meth)acrylate such as hydroxy n-butyl (meth)acrylate or hydroxy iso-butyl (meth)acrylate. Among these structural units of the hydroxyl group-containing (meth)acrylate, the structural unit of hydroxyethyl (meth)acrylate is preferred, and the structural units of 2-hydroxyethyl (meth)acrylate and hydroxybutyl (meth)acrylate are more preferred.

[0040] In the present embodiment, it is preferable that the acrylic polymer is composed of a structural unit of an alkyl (meth)acrylate having 9 or more carbon atoms, a structural unit of a hydroxyl group-containing (meth)acrylate, and a structural unit of a polymerizable group-containing (meth)acrylate. Since the acrylic polymer contains a structural unit of a polymerizable group-containing (meth)acrylate, the adhesive layer 2 can be cured by irradiating the adhesive layer 2 with active energy rays (for example, ultraviolet rays) before the pickup step. Specifically, the adhesive layer 2 can be cured by irradiating the adhesive layer 2 with active energy rays (for example, ultraviolet rays) to crosslink the acrylic polymers contained in the adhesive layer 2. From the viewpoint of facilitating the progress of the crosslinking reaction, it is preferable that the adhesive layer 2 contains a photopolymerization initiator. When the adhesive layer 2 contains a photopolymerization initiator, radicals are generated from the photopolymerization initiator by irradiating with active energy rays (for example, ultraviolet rays), and the crosslinking reaction between the acrylic polymers can be further advanced by the action of these radicals. Thus, when the adhesive layer 2 is cured by irradiation with active energy rays (for example, ultraviolet rays), the adhesive force of the adhesive layer 2 to the die bond layer 3 decreases. As a result, the semiconductor chip with a die bond layer can be easily picked up from the adhesive layer 2. Before irradiating the active energy ray (for example, ultraviolet ray), in the adhesive layer 2, since the crosslinking reaction between the acrylic polymers has not sufficiently proceeded, the adhesive layer 2 has sufficient adhesiveness and can sufficiently adhere to and hold the die bond layer 3.

[0041] The structural unit of the polymerizable group-containing (meth)acrylate can be formed by bonding a monomer having a functional group capable of bonding to a hydroxyl group and a polymerizable functional group in the molecule to the structural unit of the hydroxyl group-containing (meth)acrylate. The functional group capable of bonding to the hydrogen bond is preferably an isocyanate group having relatively high reactivity with a hydroxyl group. In such a case, the structural unit of the polymerizable group-containing (meth)acrylate preferably has an isocyanate group and a polymerizable group functional group at both ends of the molecule. Further, the polymerizable functional group is preferably a vinyl group. In such a case, the structural unit of the polymerizable group-containing (meth)acrylate preferably has an isocyanate group and a vinyl group at both ends of the molecule. Also, the vinyl group may be a part of a (meth)acryloyl group. The structural unit of the polymerizable group-containing (meth)acrylate may have a molecular structure in which the isocyanate group in the structural unit of the polymerizable group-containing (meth)acrylate containing an isocyanate group is urethane-bonded to the hydroxyl group in the structural unit of the hydroxyl group-containing (meth)acrylate. Incidentally, hereinafter, the polymerizable group-containing (meth)acrylate monomer containing an isocyanate group may be referred to as an isocyanate group-containing (meth)acrylate monomer.

[0042] When the alkyl polymer is composed of a structural unit of an alkyl (meth)acrylate having 9 or more carbon atoms, a structural unit of the hydroxyl group-containing (meth)acrylate, and a structural unit of the polymerizable group-containing (meth)acrylate, it can be obtained as follows. Specifically, an alkyl (meth)acrylate monomer having 9 or more carbon atoms and a hydroxyl group-containing (meth)acrylate monomer are subjected to a polymerization reaction to obtain an intermediate of an alkyl polymer containing a structural unit of an alkyl (meth)acrylate having 9 or more carbon atoms and a structural unit of a hydroxyl group-containing (meth)acrylate. Then, the alkyl polymer can be obtained by subjecting the intermediate of the alkyl polymer and an isocyanate group-containing (meth)acrylate monomer to a polymerization reaction. That is, the acrylic polymer can be obtained by performing the polymerization reaction in two steps. In addition, the polymerization reaction between the intermediate of the acrylic polymer and the isocyanate group-containing (meth)acrylate monomer can be carried out by forming a urethane bond between the hydroxyl group in the intermediate of the acrylic polymer and the isocyanate group of the isocyanate group-containing (meth)acrylate monomer. In addition, when obtaining the intermediate of the alkyl polymer, an alkyl (meth)acrylate monomer having 8 or less carbon atoms may be used in addition to the alkyl (meth)acrylate monomer having 9 or more carbon atoms.

[0043] The isocyanate group-containing (meth)acrylate monomer preferably has one isocyanate group and one (meth)acryloyl group in the molecule. Examples of such isocyanate group-containing (meth)acrylate monomers include 2-isocyanatoethyl (meth)acrylate and 4-acryloylmorpholine.

[0044] The adhesive layer 2 preferably contains an isocyanate compound. The isocyanate compound may be in a state after a part of it has reacted by a urethanization reaction or the like. The isocyanate compound preferably contains a plurality of isocyanate groups in the molecule. By containing a plurality of isocyanate groups, when the acrylic polymer has a structural unit of the hydroxyl group-containing (meth)acrylate, the crosslinking reaction between the acrylic polymers in the pressure-sensitive adhesive layer 2 can proceed. Specifically, by reacting one isocyanate group of the isocyanate compound with the hydroxyl group of one acrylic polymer and reacting the other isocyanate group of the isocyanate compound with the hydroxyl group of the other acrylic polymer, the crosslinking reaction can proceed through an isocyanate compound containing a plurality of isocyanate groups. That is, the isocyanate compound functions as a crosslinking agent.

[0045] The pressure-sensitive adhesive layer 2 preferably contains 0.1 part by mass or more and 10 parts by mass or less of the isocyanate compound with respect to 100 parts by mass of the acrylic polymer, and more preferably contains 0.3 part by mass or more and 7 parts by mass or less.

[0046] Examples of the isocyanate compound include diisocyanates such as aliphatic diisocyanate, alicyclic diisocyanate, and aromatic diisocyanate.

[0047] Examples of the aliphatic diisocyanate include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and methyl 2,6-diisocyanatocaproate. Examples of the alicyclic diisocyanate include 3-isocyanatomethyl-3,5,5-trimethylcyclohexane, 1,3-bis(isocyanatomethyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane, methylcyclohexane-2,4-diisocyanate, methylcyclohexane-2,6-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-diisocyanatocyclohexane, 1,4-diisocyanatocyclohexane, and the like. Examples of the aromatic diisocyanate include m-phenylene diisocyanate, p-phenylene diisocyanate, diphenylmethane-4,4'-diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3'-bis(isocyanatomethyl)benzene, 1,4'-bis(isocyanatomethyl)benzene, 1,3-bis(α-isocyanatoisopropyl)benzene, 1,4-(α-isocyanatoisopropyl), and the like.

[0048] In addition, examples of the isocyanate compound include triisocyanate. Examples of the triisocyanate include triphenylmethane-4,4',4''-triisocyanate, 1,3,5-triisocyanatobenzene, 1,3,5-tris(isocyanatomethyl)cyclohexane, 1,3,5-tris(isocyanatomethyl)benzene, 2,6-diisocyanatocaproic acid-2-isocyanatoethyl, and the like. Furthermore, examples of the isocyanate compound include polymer polyisocyanates such as dimers and trimers of diisocyanate, polymethylene polyphenylene polyisocyanate, and the like.

[0049] In addition, examples of the isocyanate compound include polyisocyanates obtained by reacting an excess of the above-described isocyanate compound with an active hydrogen-containing compound. Examples of the active hydrogen-containing compound include ethylene glycol, propylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, 2,2,4-trimethyl-1,3-pentanediol, neopentyl glycol, hexanediol, cyclohexanedimethanol, cyclohexanediol, hydrogenated bisphenol A, xylylene glycol, glycerin, trimethylolethane, trimethylolpropane, hexanetriol, pentaerythritol, sorbitol, sorbite, sucrose, castor oil, ethylenediamine, hexamethylenediamine, diethanolamine, triethanolamine, water, ammonia, urea, and the like. Also, various polyether polyols, polyester polyols, polyurethane polyols, acrylic polyols, epoxy polyols, and the like can be mentioned.

[0050] Furthermore, as the diisocyanate compound, allophanatized polyisocyanate, biuretized polyisocyanate, and the like can also be used. Each of the above-mentioned various isocyanate compounds may be used alone or in combination of two or more.

[0051] The isocyanate compound is preferably a reaction product of the aromatic diisocyanate and the active hydrogen-containing compound. Since such a reaction product has a relatively slow reaction rate of the isocyanate group, when it is included in the pressure-sensitive adhesive layer 2, it is possible to suppress the excessive progress of the curing reaction in the pressure-sensitive adhesive layer 2. As such a reaction product, it is preferable to use one containing three or more isocyanate groups in the molecule.

[0052] From the viewpoint of making the crosslinking reaction between the acrylic polymers proceed more easily, the pressure-sensitive adhesive layer 2 preferably contains a photopolymerization initiator as described above. Examples of the photoinitiator include α-ketol compounds, acetophenone compounds, benzoin ether compounds, ketal compounds, aromatic sulfonyl chloride compounds, photoactive oxime compounds, benzophenone compounds, thioxanthone compounds, camphorquinone, halogenated ketones, acylphosphine oxides, and acylphosphonates. Examples of the α-ketol compounds include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, and 1-hydroxycyclohexyl phenyl ketone. Examples of the acetophenone compounds include methoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, and 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzoyl)phenyl)-2-methylpropan-1-one. Examples of the benzoin ether compounds include benzoin ethyl ether, benzoin isopropyl ether, and anisoin methyl ether. Examples of the ketal compounds include benzyldimethyl ketal compounds. Examples of the aromatic sulfonyl chloride compounds include 2-naphthalenesulfonyl chloride. Examples of the photoactive oxime compounds include 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime. Examples of the benzophenone compounds include benzophenone, benzoin benzoic 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-diisopropylthioxanthone. Among these, it is preferable to use 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzoyl)phenyl)-2-methylpropan-1-one (as a commercially available product, Omnirad 127 manufactured by IGM Resins).

[0053] The pressure-sensitive adhesive layer 2 preferably contains 0.1 part by mass or more and 15 parts by mass or less, more preferably 1 part by mass or more and 10 parts by mass or less of the photoinitiator with respect to 100 parts by mass of the acrylic polymer.

[0054] The pressure-sensitive adhesive layer 2 may contain other components other than those described above. Examples of the other components include plasticizers, fillers, anti-aging agents, antioxidants, ultraviolet absorbers, light stabilizers, heat stabilizers, antistatic agents, surfactants, and easy-peeling agents.

[0055] The thickness of the pressure-sensitive adhesive layer 2 is preferably 1 μm or more and 60 μm or less, more preferably 2 μm or more and 50 μm or less, and even more preferably 3 μm or more and 40 μm or less. The thickness of the pressure-sensitive adhesive layer 2 can be determined, for example, by measuring the thicknesses of arbitrarily selected 5 points randomly using a dial gauge (manufactured by PEACOCK, model R-205) and calculating the arithmetic mean of these thicknesses.

[0056] In the dicing die bond film 20 according to the present embodiment, the shear storage modulus of the pressure-sensitive adhesive layer 2 at a temperature of -15°C is 10 MPa or less, and the glass transition temperature of the acrylic polymer calculated using the FOX equation is -47°C or more and 5°C or less. The shear storage modulus of the adhesive layer 2 at a temperature of -15°C is 10 MPa or less, and the glass transition temperature of the acrylic polymer calculated using FOX's equation is -47°C or higher and 5°C or lower, whereby the occurrence of cracks in the adhesive layer 2 can be suppressed. This makes it easier to pick up the semiconductor chip with the die bond layer in the pick-up process.

[0057] The shear storage modulus of the adhesive layer 2 at a temperature of -15°C is preferably 8 MPa or less, and more preferably 5 MPa or less. The shear storage modulus of the adhesive layer 2 at a temperature of -15°C is preferably 0.01 MPa or more, and more preferably 0.03 MPa or more. The glass transition temperature of the acrylic polymer calculated using FOX's equation is preferably -46°C or higher, and more preferably -44°C or higher. The glass transition temperature of the acrylic polymer calculated using FOX's equation is preferably 0°C or lower, and more preferably -4°C or lower. Since the shear storage modulus of the adhesive layer 2 at a temperature of -15°C is within the above numerical range, and the glass transition temperature of the acrylic polymer calculated using FOX's equation is within the above numerical range, the occurrence of cracks in the adhesive layer 2 can be further suppressed. This makes it even easier to pick up the semiconductor chip with the die bond layer in the pick-up process.

[0058] The shear storage modulus of the adhesive layer 2 at a temperature of -15°C can be measured as follows. (1) The adhesive composition is applied onto a separator so as to have a thickness of 30 μm to obtain a separator with an adhesive layer. (2) The adhesive layers of the separator with the adhesive layer are stacked 32 layers to obtain a laminate of the adhesive layer with a thickness of 960 μm. (3) The laminate of the adhesive layer is punched into a circle with a diameter of 8 mm to obtain a test piece. (4) Using a viscoelasticity measuring device (for example, trade name "ARES-G2", manufactured by TA Instruments), measure the shear storage modulus of the test specimen in the temperature range of -50 to 100°C under the conditions of a frequency of 1 Hz, a strain of 0.1%, a heating rate of 1°C / min, and an Axial Force of 30 gf. By reading the value at -15°C at that time, the modulus of the adhesive layer at -15°C is determined.

[0059] The FOX equation is an equation that shows the relationship between the glass transition temperature (Tg) of a copolymer and the glass transition temperatures (Tgi) of the homopolymers obtained by polymerizing each of the monomers constituting the copolymer alone, as shown in the following equation (1).

[0060] [Equation] However, Tg is the glass transition temperature of the copolymer (unit: K), Wi is the mass fraction of monomer i in the copolymer, and Tgi is the glass transition temperature of the homopolymer of monomer i (unit: K).

[0061] As the transition temperature of the homopolymer used for calculating Tg, values described in publicly known materials can be used. Examples of publicly known materials include "Polymer Handbook" (3rd edition, John Wiley & Sons, Inc., 1989). Incidentally, in the above Polymer Handbook, the glass transition temperature of the homopolymer of lauryl acrylate (LA) is described as 270 K, the glass transition temperature of the homopolymer of 2-ethylhexyl acrylate (2EHA) is described as 223 K, the glass transition temperature of the homopolymer of butyl acrylate (BA) is described as 219 K, and the glass transition temperature of the homopolymer of ethyl acrylate (EA) is described as 249 K.

[0062] As the glass transition temperature of the homopolymer of a monomer not described in the above Polymer Handbook, the values described in the catalogs of various monomer manufacturers can be used. For example, the catalog of Osaka Organic Chemical Industry Co., Ltd. describes that the glass transition temperature of the homopolymer of isononyl acrylate (INA) is -58 °C (215 K). Also, the catalog of KJ Chemicals Co., Ltd. describes that the glass transition temperature of the homopolymer of acryloylmorpholine (ACMO) is 145 °C (418 K). Furthermore, the catalog of Kyoeisha Chemical Co., Ltd. describes that the glass transition temperature of the homopolymer of 2-hydroxyethyl acrylate (HEA) is -15 °C (258 K). Here, when 2-hydroxyethyl acrylate (HEA) is used as the alkyl (meth)acrylate monomer, 2-isocyanatoethyl methacrylate (MOI) may be used as the monomer. Since the 2-isocyanatoethyl methacrylate (MOI) is a substance that undergoes an addition reaction to the functional group of 2-hydroxyethyl acrylate (HEA), it is considered that the influence on the glass transition temperature of the copolymer is small. Therefore, in such a case, the value of the glass transition temperature of the homopolymer of 2-isocyanatoethyl methacrylate (MOI) is not used for calculating the glass transition temperature using the FOX equation. Note that as a commercially available product of 2-isocyanatoethyl methacrylate (MOI), the product name "Karenz MOI (registered trademark)" manufactured by Showa Denko KK can be mentioned. According to the catalog of Showa Denko KK, the glass transition temperature of the homopolymer of 2-isocyanatoethyl methacrylate is 60 °C (333 K).

[0063] Regarding the reason why the dicing die bond film 20 according to this embodiment can suppress the occurrence of cracks in the adhesive layer during the expansion process, the present inventors speculate as follows.

[0064] The adhesive layer 2 of the dicing die bond film 20 contains a resin such as an acrylic polymer in order to exhibit adhesiveness. Here, since the cool expansion in the expansion process is usually carried out at a temperature in the range of -20°C to 5°C, if the glass transition temperature Tg of the resin contained in the adhesive layer 2 is too low compared to the temperature at which the cool expansion is carried out, and furthermore, if the value of the shear storage modulus of the adhesive layer 2 is too low, it is considered that the adhesive layer 2 becomes too fluid and cannot transmit sufficient force to the die bond layer 3. And in such a case, it is considered that the die bond layer 3 cannot be sufficiently severed. On the other hand, if the glass transition temperature Tg of the resin contained in the adhesive layer 2 is sufficiently higher than the temperature at which the cool expansion is carried out, and furthermore, if the value of the shear storage modulus of the adhesive layer 2 is sufficiently high, the adhesive layer 2 becomes glassy (lacking in fluidity) and can transmit sufficient force to the die bond layer 3. As a result, although the die bond layer 3 can be sufficiently severed, it is considered that the adhesive layer 2 will also crack due to becoming glassy. However, in the dicing die bond film 20 according to the present embodiment, the shear storage modulus of the adhesive layer 2 at a temperature of -15°C is 10 MPa or less, and the glass transition temperature of the acrylic polymer calculated using FOX's formula is -47°C or higher and 5°C or lower. Therefore, it is considered that the adhesive layer 2 has appropriate fluidity and appropriate hardness when the cool expansion is carried out in the expansion process. Therefore, the inventors speculate that when the cool expansion is carried out in the expansion process, the occurrence of cracks in the adhesive layer 2 can be suppressed. Also, as described above, since the adhesive layer 2 is considered to have appropriate fluidity and appropriate hardness, it is considered that the die bond layer can be sufficiently severed when the cool expansion is carried out in the expansion process.

[0065] Note that the value of the shear storage modulus of the pressure-sensitive adhesive layer 2 at a temperature of -15°C can be adjusted by appropriately adjusting the content of the acrylic polymer in the pressure-sensitive adhesive layer 2 or the like. Also, the value of the shear storage modulus of the pressure-sensitive adhesive layer 2 at a temperature of -15°C can be more easily adjusted by appropriately selecting the constituent units of (meth)acrylate in the acrylic polymer. Furthermore, the value of the shear storage modulus of the pressure-sensitive adhesive layer 2 at a temperature of -15°C can be more easily adjusted by appropriately selecting materials added to the acrylic polymer, such as crosslinking agents and tackifiers (adhesion promoters).

[0066] The pressure-sensitive adhesive layer 2 can be obtained by applying a pressure-sensitive adhesive composition containing each component as described above to the surface of a resin film or the like using an applicator or the like, and then drying the applied pressure-sensitive adhesive composition.

[0067] The die bond layer 3 contains a resin component. The die bond layer 3 preferably has thermosetting properties. By including at least one of a thermosetting resin and a thermoplastic resin having a thermosetting functional group in the die bond layer 3, the die bond layer 3 can be made to have thermosetting properties.

[0068] When the die bond layer 3 contains a thermosetting resin, examples of such thermosetting resins include epoxy resins, phenol resins, amino resins, unsaturated polyester resins, polyurethane resins, silicone resins, and thermosetting polyimide resins. Among these, it is preferable to use an epoxy resin.

[0069] Examples of the epoxy resin include bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolak type, ortho-cresol novolak type, trishydroxyphenylmethane type, tetraphenylol ethane type, hydantoin type, tris glycidyl isocyanurate type, and glycidylamine type epoxy resins.

[0070] Examples of the phenol resin include novolak type phenol resin, resol type phenol resin, and polyoxy styrenes such as polyparaoxy styrene. Note that the phenol resin functions as a curing agent for the epoxy resin.

[0071] When the die bond layer 3 contains a thermoplastic resin having a thermosetting functional group, examples of such a thermoplastic resin include a thermosetting functional group-containing acrylic resin. Examples of the acrylic resin in the thermosetting functional group-containing acrylic resin include those containing monomer units derived from (meth)acrylate esters. In a thermosetting resin having a thermosetting functional group, a curing agent is selected according to the type of the thermosetting functional group.

[0072] Examples of the (meth)acrylic acid ester include (meth)acrylic acid alkyl esters, (meth)acrylic acid cycloalkyl esters, (meth)acrylic acid aryl esters, and the like. The acrylic resin may contain monomer units derived from other components copolymerizable with the (meth)acrylic acid ester. Examples of the other components include functional group-containing monomers such as carboxy group-containing monomers, acid anhydride monomers, hydroxy group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, acrylamide, and acrylonitrile, and various polyfunctional monomers. From the viewpoint of achieving high cohesive force in the die bond layer, the acrylic resin is preferably a copolymer of a (meth)acrylic acid ester (particularly, a (meth)acrylic acid alkyl ester having 4 or less carbon atoms in the alkyl group), a carboxy group-containing monomer, a nitrogen atom-containing monomer, and a polyfunctional monomer (particularly, a polyglycidyl-based polyfunctional monomer), and more preferably a copolymer of ethyl acrylate, butyl acrylate, acrylic acid, acrylonitrile, and polyglycidyl (meth)acrylate.

[0073] The die bond layer 3 may contain a thermosetting catalyst (curing accelerator) from the viewpoint of allowing the curing reaction of the resin component to proceed sufficiently or increasing the curing reaction rate. Examples of the thermosetting catalyst include imidazole-based compounds, triphenylphosphine-based compounds, amine-based compounds, and trihalogenoborane-based compounds. The die bond layer 3 preferably contains an imidazole-based compound as the thermosetting catalyst. Examples of the imidazole-based compound include 2-phenyl-4,5-dihydroxymethylimidazole. Examples of the commercially available product of 2-phenyl-4,5-dihydroxymethylimidazole include the product name "Curezol 2PHZ-PW" manufactured by Shikoku Kasei Co., Ltd.

[0074] The die bond layer 3 may contain a thermoplastic resin as the resin component. The thermoplastic resin functions as a binder. Examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resins such as polyamide 6 and polyamide 6,6, phenoxy resin, acrylic resin, saturated polyester resins such as PET and PBT, polyamideimide resin, fluororesin, and the like. Only one kind of the above thermoplastic resin may be used, or two or more kinds may be used in combination. From the viewpoint that the connection reliability by the die bond layer 3 is easily ensured because the thermoplastic resin has few ionic impurities and high heat resistance, an acrylic resin is preferable.

[0075] The above acrylic resin is preferably a polymer containing, as the monomer unit having the largest mass ratio, a monomer unit derived from a (meth)acrylate ester. As the (meth)acrylate ester, the same ones as those described above can be used.

[0076] The die bond layer 3 may contain one or more other components as necessary. Examples of the other components include a flame retardant, a silane coupling agent, and an ion trap agent.

[0077] The thickness of the die bond layer 3 is not particularly limited, but is, for example, 1 μm or more and 200 μm or less. Such a thickness may be 3 μm or more and 150 μm or less, or may be 5 μm or more and 100 μm or less. The thickness of the die bond layer 3 can be obtained, for example, by measuring the thicknesses of arbitrarily selected five points randomly using a dial gauge (manufactured by PEACOCK, model R-205) and calculating the arithmetic mean of these thicknesses.

[0078] The die bond layer 3 may contain a filler. By changing the amount of the filler contained in the die bond layer 3, the elasticity and viscosity of the die bond layer 3 can be adjusted more easily. In addition, physical properties such as the conductivity, thermal conductivity, and elastic modulus of the die bond layer 3 can be adjusted. Examples of the filler include inorganic fillers and organic fillers. As the filler, inorganic fillers are preferred. Examples of the inorganic filler include fillers containing silica such as aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, boron nitride, crystalline silica, and amorphous silica. In addition, examples of the material of the inorganic filler include simple metals such as aluminum, gold, silver, copper, and nickel, and alloys. The inorganic filler may be aluminum borate whisker, amorphous carbon black, graphite, or the like. The shape of the filler may be various shapes such as spherical, needle-like, and flake-like. As the filler, only one of the above may be used, or two or more of the above may be used in combination.

[0079] The average particle size of the filler is preferably 0.005 μm or more and 10 μm or less, and more preferably 0.005 μm or more and 1 μm or less. When the average particle size of the filler is 0.005 μm or more, the wettability and adhesiveness to an adherend such as a semiconductor wafer can be further improved. In addition, when the average particle size of the filler is 10 μm or less, in addition to being able to more sufficiently exhibit the characteristics of the contained filler, the heat resistance of the die bond layer 3 can be further exhibited. The average particle size of the filler can be determined, for example, using a photometric particle size distribution meter (for example, product name "LA-910", manufactured by Horiba, Ltd.).

[0080] When the die bond layer 3 contains a filler, the content thereof is preferably 30% by mass or more and 70% by mass or less, more preferably 40% by mass or more and 60% by mass or less, and still more preferably 42% by mass or more and 55% by mass or less with respect to the total mass of the die bond layer 3.

[0081] The thickness of the die bond layer 3 is not particularly limited, but is, for example, 1 μm or more and 200 μm or less. Such thickness may be 3 μm or more and 150 μm or less, or may be 5 μm or more and 135 μm or less.

[0082] Note that the die bond layer 3 can be obtained by applying an adhesive composition containing each component as described above onto the surface of a resin film or the like using an applicator or the like, and then drying the applied adhesive composition. In addition, the attachment of the die bond layer 3 to the pressure-sensitive adhesive layer 2 can be carried out by laminating the die bond layer 3 onto the pressure-sensitive adhesive layer 2 produced as described above.

[0083] The base material layer 1 supports the pressure-sensitive adhesive layer 2. The base material layer 1 is produced using a metal foil, a fiber sheet, a rubber sheet, a resin film, or the like. The base material layer 1 is preferably produced using a resin film. The base material layer 1 may have a single-layer structure or a laminated structure.

[0084] Examples of the fiber sheet include those composed of paper, woven fabric, or non-woven fabric.

[0085] Examples of the material of the resin film include polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymer; copolymers of ethylene such as ethylene-vinyl acetate copolymer, ionomer resin, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate random copolymer, and ethylene-(meth)acrylate alternating copolymer; polyesters such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate; polyacrylate; polyvinyl chloride (PVC); polyurethane; polycarbonate; polyphenylene sulfide; polyamides such as aliphatic polyamide and wholly aromatic polyamide (aramid); polyetheretherketone; polyimide; polyetherimide; polyvinylidene chloride; ABS (acrylonitrile-butadiene-styrene copolymer); cellulose or cellulose derivative; silicone-containing polymer; fluorine-containing polymer, and the like. These may be used alone or in combination of two or more.

[0086] When the base material layer 1 is made of a resin film, the base material layer 1 may be obtained by non-stretching molding or stretching molding, but it is preferably obtained by stretching molding.

[0087] The surface of the base material layer 1 on the side where the adhesive layer 2 is laminated (hereinafter, also simply referred to as the surface) may be subjected to a surface treatment from the viewpoint of enhancing the adhesion to the adhesive layer 2. As the surface treatment, an oxidation treatment by a chemical method or a physical method such as chromic acid treatment, ozone exposure, flame exposure, high-voltage electric shock exposure, or ionization radiation treatment may be employed. Further, as the surface treatment, a coating treatment with a coating agent such as an anchor coating agent, a primer, or an adhesive may be performed.

[0088] The surface of the base material layer 1 on the side where the adhesive layer 2 is not laminated (hereinafter, also simply referred to as the back surface) may be subjected to a coating treatment with a release agent (peeling agent) such as a silicone resin or a fluororesin in order to enhance the peelability.

[0089] The thickness of the base material layer 1 is preferably 55 μm or more and 195 μm or less, more preferably 55 μm or more and 190 μm or less, still more preferably 55 μm or more and 170 μm or less, and most preferably 60 μm or more and 160 μm or less. By setting the thickness of the base material layer 1 within the above range, the dicing tape 10 can be efficiently manufactured. Also, the dicing bond layer 3 of the dicing die bond film 20 can be efficiently cut. The thickness of the base material layer 1 can be obtained, for example, by measuring the thicknesses of arbitrarily selected five points randomly using a dial gauge (manufactured by PEACOCK, model R-205) and calculating the arithmetic mean of these thicknesses.

[0090] In the dicing die bond film 20 according to the present embodiment, the thickness of the dicing tape 10 is preferably 50 μm or more and 250 μm or less. The thickness of the dicing tape 10 is the sum of the thickness of the base material layer 1 and the thickness of the adhesive layer 2. When the thickness of the dicing tape 10 is within the above numerical range, it is possible to further suppress the occurrence of cracks in the adhesive layer 2 in the expansion process. As a result, in the pickup process, it becomes easier to pick up the semiconductor chip with the dicing bond layer. The thickness of the dicing tape 10 can be obtained, for example, by measuring the thicknesses of arbitrarily selected five points randomly using a dial gauge (manufactured by PEACOCK, model R-205) and calculating the arithmetic mean of these thicknesses.

[0091] In the dicing die bond film 20 according to the present embodiment, the 25% tensile strength of the dicing tape 10 is preferably 2 N / 10 mm or more and 50 N / 10 mm or less. When the 25% tensile strength of the dicing tape 10 is within the above numerical range, it is possible to further suppress the occurrence of cracks in the adhesive layer 2 in the expansion process. As a result, in the pickup process, it becomes easier to pick up the semiconductor chip with the die bond layer. It is more preferable that the 25% tensile strength of the dicing tape 10 is 3 N / 10 mm or more. It is more preferable that the 25% tensile strength of the dicing tape 10 is 30 N / 10 mm or less, and it is even more preferable that it is 25 N / 10 mm or less. The 25% tensile strength of the dicing tape 10 can be obtained by a tensile test using a tensile testing machine (for example, model "AG-X / R", manufactured by Shimadzu Corporation). Specifically, as a test piece, a dicing tape with a width of 10 mm and a length of 200 mm is used, and a tensile test is performed using a tensile testing machine (for example, model "AG-X / R", manufactured by Shimadzu Corporation) under the conditions of a chuck distance of 50 mm and a tensile speed of 300 mm / min. The force (test force) applied when the elongation rate at that time reaches 25% can be obtained by reading it.

[0092] In the dicing die bond film 20 according to the present embodiment, it is preferable that the 180° peel strength between the base material layer 1 and the adhesive layer 2 is 1.0 N / 20 mm or more at room temperature. Note that room temperature means 23 ± 2°C. Since the 180° peel strength between the base material layer 1 and the adhesive layer 2 is within the above numerical range at room temperature, it is possible to further suppress the occurrence of cracks in the adhesive layer 2 in the expand process. As a result, in the pickup process, it becomes easier to pick up the semiconductor chip with the die bond layer. In the dicing die bond film 20 according to the present embodiment, it is more preferable that the 180° peel strength between the base material layer 1 and the adhesive layer 2 is 1.0 N / 20 mm or more at room temperature. It is preferable that the 180° peel strength between the base material layer 1 and the adhesive layer 2 is 1.2 N / 20 mm or more, and it is even more preferable that it is 1.5 N / 20 mm or more. The 180° peel test of the base material layer 1 and the adhesive layer 2 can be measured for the dicing tape 10 (a laminate of the base material layer 1 and the adhesive layer 2) in the dicing die bond film 20 using a tensile testing machine (model "AGX-V", manufactured by Shimadzu Corporation). Specifically, it can be measured as follows. (1) Cut the dicing tape 10 into a size of 150 mm in length × 20 mm in width to obtain a sample piece. Note that the dicing tape 10 is cut so that the resin flow direction (MD) is the length direction of the sample piece. (2) Make a single cut with a length of 20 mm in the adhesive layer 2 of the sample piece. The single cut is made along the TD (direction perpendicular to the resin flow direction) at a position 50 mm in the length direction (a position 50 mm away from one end edge in the length direction). That is, the single cut is made to have the same size as the width of the adhesive layer 2. Also, the single cut is made to penetrate the adhesive layer 2 in the thickness direction. (3) Paste a polyester adhesive tape (product name "ELP BT-315", manufactured by Nitto Denko Corporation) cut into a size of 150 mm in length × 25 mm in width so as to cover the single cut to obtain a test piece. Note that the polyester adhesive tape is pasted using a hand roller. (4) Clamp the dicing tape of the test piece with one chuck of a tensile testing machine (model "AGX-V", manufactured by Shimadzu Corporation), and clamp the polyester adhesive tape of the test piece with the other chuck, and perform a 180° peel test at a measurement speed of 300 mm / min. The 180° peel test is performed by peeling the test piece in the length direction. In the above 180° peel test, when the adhesive layer 2 is peeled from the base material layer 1, read the value of the peel strength, and when the adhesive layer 2 is not peeled from the base material layer 1, evaluate it as no anchor failure.

[0093] In the dicing die bond film 20 according to the present embodiment, it is preferable that the dicing tape 10 has no crack in the adhesive layer 2 when it is stretched by 200% at a tensile speed of 1000 mm / min at a temperature of -15°C. Note that having no crack in the adhesive layer 2 means that when a test of stretching the dicing tape 10 by 200% at a tensile speed of 1000 mm / min at a temperature of -15°C is performed, and data on strain (tensile length) and tensile strength are obtained, when a graph with strain (tensile length) on the horizontal axis and tensile strength on the vertical axis is drawn, the instantaneous decrease in tensile strength is less than 3%. That is, it does not mean that a decrease in tensile strength of less than 3% occurs continuously. And since a tensile speed of 1000 / min means pulling the dicing tape 10 at a high speed, the stretching condition of a tensile speed of 1000 mm / min at a temperature of -15°C means performing cool expansion in the expand process at a high speed. Therefore, when the dicing tape 10 is stretched by 200% at a tensile speed of 1000 mm / min at a temperature of -15°C and no crack occurs in the adhesive layer 2, the occurrence of cracks in the adhesive layer 2 can be further suppressed in the expand process. As a result, since a sufficient distance between chips can be ensured, it becomes easier to pick up semiconductor chips with a die bond layer in the pick-up process. As a result, in the manufacturing process of the semiconductor integrated circuit, the tact time can be shortened. The test of stretching by 200% at a tensile speed of 1000 mm / min at a temperature of -15°C can be performed using a tensile tester (a tensile tester with a thermostat manufactured by Shimadzu Corporation).

[0094] The dicing die bond film 20 according to the present embodiment is preferably used for dicing a semiconductor wafer. For example, the dicing die bond film 20 according to the present embodiment is preferably used as an auxiliary tool for manufacturing a semiconductor integrated circuit.

[0095] As described above, the dicing die bond film 20 according to the present embodiment is used, for example, as an auxiliary tool for manufacturing semiconductor integrated circuits. Hereinafter, specific examples of the use of the dicing die bond film 20 will be described. Hereinafter, an example using the dicing die bond film 20 in which the base material layer 1 is a single layer will be described.

[0096] A method for manufacturing a semiconductor integrated circuit includes a half-cut step of forming grooves in a semiconductor wafer to process the semiconductor wafer into chips (dies) by a dicing process, a back grinding step of grinding the semiconductor wafer after the half-cut step to reduce the thickness, a mounting step of attaching one surface (for example, the surface opposite to the circuit surface) of the semiconductor wafer after the back grinding step to the die bond layer 3 and fixing the semiconductor wafer to the dicing tape 10, an expand step of widening the space between the semiconductor chips, a kerf maintenance step of maintaining the space between the semiconductor chips, a pickup step of peeling between the die bond layer 3 and the adhesive layer 2 and taking out the semiconductor chip (die) with the die bond layer 3 attached, and a die bond step of bonding the semiconductor chip (die) with the die bond layer 3 attached to an adherend. When these steps are carried out, the dicing tape (dicing die bond film) of the present embodiment is used as a manufacturing auxiliary tool.

[0097] In the half-cut process, as shown in FIGS. 2A and 2B, a half-cut process for cutting the semiconductor wafer into small pieces (dies) is performed. Specifically, a wafer processing tape T is attached to the surface of the semiconductor wafer W opposite to the circuit surface (see FIG. 2A). Further, a dicing ring R is attached to the wafer processing tape T (see FIG. 2A). In a state where the wafer processing tape T is attached, a dividing groove is formed (see FIG. 2B). In the back grinding process, as shown in FIGS. 2C and 2D, the semiconductor wafer is ground to reduce its thickness. Specifically, a back grinding tape G is attached to the surface where the groove is formed, while the wafer processing tape T attached at the beginning is peeled off (see FIG. 2C). In a state where the back grinding tape G is attached, grinding is performed until the semiconductor wafer W reaches a predetermined thickness (see FIG. 2D). In addition, in the back grinding process, when the thickness of the semiconductor wafer is particularly thin, i.e., 20 μm or more and 30 μm or less, in the pickup process described later, when the semiconductor chip is pushed up using the pin member P, the semiconductor chip is likely to be deformed or cracked. However, since the dicing die bond film 20 according to the present embodiment is configured as described above, in the pickup process, it is possible to relatively suppress the occurrence of deformation or cracking in the semiconductor chip.

[0098] In the mounting process, as shown in FIGS. 3A to 3B, after attaching the dicing ring R to the adhesive layer 2 of the dicing tape 10, the half-cut semiconductor wafer W is attached to the exposed surface of the die bond layer 3 (see FIG. 3A). Then, the back grinding tape G is peeled off from the semiconductor wafer W (see FIG. 3B).

[0099] In the expansion process, as shown in FIGS. 4A to 4C, the dicing ring R is fixed to the holder H of the expansion device. By using the pushing member U provided in the expansion device to push up the dicing die bond film 20 from below, the dicing die bond film 20 is stretched so as to expand in the plane direction (see FIG. 4B). Thereby, under specific temperature conditions, the semiconductor wafer W that has been half-cut is cut. The above temperature conditions are, for example, -20 to 5°C, preferably -15 to 0°C, and more preferably -10 to -5°C. By lowering the pushing member U, the expanded state is released (see FIG. 4C). Furthermore, in the expansion process, as shown in FIGS. 5A to 5B, under higher temperature conditions (for example, room temperature (23 ± 2°C)), the dicing tape 10 is stretched so as to expand in area. Thereby, the adjacent cut semiconductor chips are separated in the plane direction of the film surface, and the distance therebetween is further increased. In the dicing die bond film 20 according to the present embodiment, the shear storage modulus of the adhesive layer 2 at a temperature of -15°C is 10 MPa or less, and the glass transition temperature of the acrylic polymer contained in the adhesive layer 2 calculated using FOX's formula is -47°C or higher and 5°C or lower. Therefore, in the expansion process, it is possible to suppress the occurrence of cracks in the adhesive layer 2. Thereby, in the subsequent pickup process, it becomes easier to pick up the semiconductor chip with the die bond layer.

[0100] In the kerf maintenance process, as shown in FIG. 6, hot air (for example, 100 to 130°C, indicated by an arrow) is applied to the dicing tape 10 to thermally shrink the dicing tape 10 and then cooled and solidified to maintain the distance (kerf) between adjacent cut semiconductor chips.

[0101] In the pickup process, as shown in FIG. 7, the semiconductor chip with the die bond layer 3 attached is peeled off from the adhesive layer 2 of the dicing tape 10. Specifically, the pin member P is raised to push up the semiconductor chip to be picked up through the dicing tape 10. The pushed-up semiconductor chip is held by the suction jig J.

[0102] In the die bonding process, a semiconductor chip with a die bonding layer 3 attached is bonded to a substrate.

[0103] Note that the dicing die bonding film according to the present invention is not limited to the above embodiment. Also, the dicing die bonding film according to the present invention is not limited by the above-described effects. The dicing die bonding film according to the present invention can be variously modified without departing from the gist of the present invention.

Example

[0104] Next, the present invention will be described more specifically with reference to examples. The following examples are for further explaining the present invention and do not limit the scope of the present invention.

[0105] [Example 1] <Synthesis of Acrylic Polymer> Into a reaction vessel equipped with a cooling pipe, a nitrogen introduction pipe, a thermometer, and a stirring device, (meth)acrylic monomers are put in the mixing ratios shown in Table 1 below. At the same time, azobisisobutyronitrile (hereinafter referred to as AIBN), as a thermal polymerization initiator, is added in an amount of 0.2 parts by mass with respect to 100 parts by mass of the (meth)acrylic monomers. Further, butyl acetate as a reaction solvent is added so that the concentration of the (meth)acrylic monomers becomes 38%. After that, butyl acetate as a reaction solvent is further added so that the concentration of the monomers becomes 38%. Then, polymerization is carried out at 62°C for 4 hours and polymerization treatment is carried out at 75°C for 2 hours under a nitrogen stream to obtain a first acrylic polymer as an intermediate. Into the solution containing this first acrylic polymer, (meth)acrylic monomers are put in the mixing ratios shown in Table 1 below. At the same time, 0.06 parts by mass of dibutyltin dilaurate is added with respect to 100 parts by mass of the first acrylic polymer A. An addition reaction treatment is carried out at 50°C for 12 hours under an air stream to obtain an acrylic polymer according to Example 1. Here, when obtaining the first acrylic polymer, 2-isocyanatoethyl methacrylate (hereinafter referred to as MOI) is used as the (meth)acrylic monomer. However, since MOI undergoes addition polymerization with HEA, it is not included in the molar percentage of the (meth)acrylate monomer. In addition, as the MOI, the product name "Karenz MOI (registered trademark)" manufactured by Showa Denko KK was used. "Karenz MOI (registered trademark)" is a polymerizable group-containing (meth)acrylate having an isocyanate group and has a vinyl group as the polymerizable group.

[0106] <Preparation of Adhesive Solution> To the solution containing the acrylic polymer according to Example 1, a polyisocyanate compound (product name "Coronate L", manufactured by Nippon Polyurethane Industry Co., Ltd.) as a crosslinking agent and a photopolymerization initiator (product name "Omnirad127", manufactured by IGM Resins) were added at the blending ratios shown in Table 1 below to prepare the adhesive solution according to Example 1. Note that the parts by mass of the crosslinking agent and the parts by mass of the photopolymerization initiator shown in Table 1 below are values relative to 100 parts by mass of the acrylic polymer according to Example 1.

[0107] <Preparation of Dicing Tape> The adhesive solution according to Example 1 was applied onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface using an applicator, dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm. Then, a polyolefin film (product name "Funclare NED#125", thickness: 125 μm) manufactured by Gunze was laminated as a base material layer on the adhesive layer, and stored at 50°C for 24 hours to obtain the dicing tape according to Example 1.

[0108] <Preparation of Die Bond Layer> To 100 parts by mass of an acrylic resin (trade name "SG-N80", manufactured by Nagase ChemteX Corporation, glass transition temperature -23°C), 210 parts by mass of an epoxy resin (trade name "EPPN 501HY", manufactured by Nippon Kayaku Co., Ltd.), 100 parts by mass of phenol resin 1 (trade name "LVR8210-DL", manufactured by Gunei Chemical Industry Co., Ltd.), 33 parts by mass of phenol resin 2 (trade name "HF-1M", manufactured by Meiwafosis Co., Ltd.), 440 parts by mass (in terms of spherical silica) of spherical silica (trade name "SE2050-MCV", manufactured by Admatechs Co., Ltd., average particle diameter 500 nm), 3 parts by mass of a silane coupling agent (trade name "KBM-303", manufactured by Shin-Etsu Chemical Co., Ltd.), and 0.5 parts by mass of a thermosetting catalyst (trade name "TPP-K", manufactured by Hokko Chemical Industry Co., Ltd.) were added to methyl ethyl ketone and mixed to prepare the adhesive composition according to Example 1. Next, the adhesive composition according to Example 1 was applied onto the silicone release-treated surface of a PET separator (thickness 50 μm) having a silicone release-treated surface using an applicator to form a coating film, and this coating film was subjected to a solvent removal treatment at 130°C for 2 minutes. Thereby, a die bond layer with a thickness (average thickness) of 30 μm was produced on the PET separator (a PET separator with a die bond layer was produced). Then, after overlapping the die bond layers of two sets of PET separators with die bond layers, lamination was performed using a roll laminator to produce a die bond layer with a thickness of 60 μm. Note that the lamination using the roll laminator was performed under the conditions of a lamination speed of 10 mm / second, a temperature of 90°C, and a pressure of 0.15 MPa.

[0109] <Production of Dicing Die Bond Film> The PET separator with a die bond layer (hereinafter referred to as a PET separator with a die bond layer) having a die bond layer was punched out into a circle with a diameter of 330 mm (330 mmφ) to obtain a PET separator with a die bond layer having a diameter of 330 mm (330 mmφ). Next, after removing the PET separator from the dicing tape according to Example 1 to expose one surface of the adhesive layer, using a laminator, at room temperature (23 ± 2°C), the PET separator with a die bond layer was bonded to the dicing tape according to Example 1 so that the exposed surface of the die bond layer abutted the exposed surface of the adhesive layer, thereby obtaining a dicing die bond film according to Example 1. That is, the dicing tape according to Example 1 was configured by laminating a polyolefin film, an adhesive layer, a die bond layer, and a PET separator in this order.

[0110] [Example 2] [Synthesis of Acrylic Polymer] An acrylic monomer according to Example 2 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer was in the blending ratio shown in Table 1 below. [Preparation of Adhesive Solution] Using the acrylic monomer according to Example 2, an adhesive solution according to Example 2 was obtained in the same manner as in Example 1. [Preparation of Dicing Tape] Using the adhesive solution according to Example 2, a dicing tape according to Example 2 was obtained in the same manner as in Example 1. [Preparation of Die Bond Layer] A die bond layer according to Example 2 was obtained in the same manner as in Example 1. [Preparation of Dicing Die Bond Film] Using the dicing tape according to Example 2 and the die bond layer according to Example 2, a dicing die bond film according to Example 2 was obtained in the same manner as in Example 1.

[0111] [Example 3] [Synthesis of Acrylic Polymer] An acrylic monomer according to Example 3 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer was in the blending ratio shown in Table 1 below. [Preparation of Adhesive Solution] Using the acrylic monomer according to Example 3, an adhesive solution according to Example 3 was obtained in the same manner as in Example 1. <Production of Dicing Tape> Using the adhesive solution according to Example 3, in the same manner as in Example 1, a dicing tape according to Example 3 was obtained. <Production of Die Bond Layer> In the same manner as in Example 1, a die bond layer according to Example 3 was obtained. <Production of Dicing Die Bond Film> Using the dicing tape according to Example 3 and the die bond layer according to Example 3, in the same manner as in Example 1, a dicing die bond film according to Example 3 was obtained.

[0112] [Example 4] <Synthesis of Acrylic Polymer> An acrylic monomer according to Example 4 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer was in the blending ratio shown in Table 1 below. <Production of Adhesive Solution> Using the acrylic monomer according to Example 4, in the same manner as in Example 1, an adhesive solution according to Example 4 was obtained. <Production of Dicing Tape> Using the adhesive solution according to Example 4, in the same manner as in Example 1, a dicing tape according to Example 4 was obtained. <Production of Die Bond Layer> In the same manner as in Example 1, a die bond layer according to Example 4 was obtained. <Production of Dicing Die Bond Film> Using the dicing tape according to Example 4 and the die bond layer according to Example 4, a dicing die bond film according to Example 4 was obtained.

[0113] [Example 5] <Synthesis of Acrylic Polymer> An acrylic monomer according to Example 5 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer was in the blending ratio shown in Table 1 below. <Production of Adhesive Solution> Using the acrylic monomer according to Example 5, in the same manner as in Example 1, an adhesive solution according to Example 5 was obtained. <Fabrication of Dicing Tape> Using the adhesive solution according to Example 5, in the same manner as in Example 1, a dicing tape according to Example 5 was obtained. <Fabrication of Die Bond Layer> In the same manner as in Example 1, a die bond layer according to Example 5 was obtained. <Fabrication of Dicing Die Bond Film> Using the dicing tape according to Example 5 and the die bond layer according to Example 5, a dicing die bond film according to Example 5 was obtained.

[0114] [Example 6] <Synthesis of Acrylic Polymer> An acrylic monomer according to Example 6 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer was in the blending ratio shown in Table 1 below. <Fabrication of Adhesive Solution> Using the acrylic polymer according to Example 6, an adhesive solution according to Example 6 was obtained in the same manner as in Example 1, except that the crosslinking agent (Coronate L) and the photopolymerization initiator (Omnirad 127) were in the blending ratio shown in Table 1 below. <Fabrication of Dicing Tape> Using the adhesive solution according to Example 6, in the same manner as in Example 1, a dicing tape according to Example 6 was obtained. <Fabrication of Die Bond Layer> In the same manner as in Example 1, a die bond layer according to Example 6 was obtained. <Fabrication of Dicing Die Bond Film> Using the dicing tape according to Example 6 and the die bond layer according to Example 6, a dicing die bond film according to Example 6 was obtained.

[0115] [Example 7] <Synthesis of Acrylic Polymer> An acrylic monomer according to Example 7 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer was in the blending ratio shown in Table 1 below. <Fabrication of Adhesive Solution> Using the acrylic polymer according to Example 7, an adhesive solution according to Example 7 was obtained in the same manner as in Example 1, except that the crosslinking agent (Coronate L) and the photopolymerization initiator (Omnirad 127) were used in the blending ratios shown in Table 1 below. <Fabrication of Dicing Tape> Using the adhesive solution according to Example 7, a dicing tape according to Example 7 was obtained in the same manner as in Example 1. <Fabrication of Die Bond Layer> A die bond layer according to Example 7 was obtained in the same manner as in Example 1. <Fabrication of Dicing Die Bond Film> Using the dicing tape according to Example 7 and the die bond layer according to Example 7, a dicing die bond film according to Example 7 was obtained.

[0116] [Comparative Example 1] <Synthesis of Acrylic Polymer> An acrylic polymer according to Comparative Example 1 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer was used in the blending ratio shown in Table 1 below. <Fabrication of Adhesive Solution> Using the acrylic polymer according to Comparative Example 1, an adhesive solution according to Comparative Example 1 was obtained in the same manner as in Example 1, except that the crosslinking agent (Coronate L) was used in the blending ratio shown in Table 1 below. <Fabrication of Dicing Tape> Using the adhesive solution according to Comparative Example 1, a dicing tape according to Comparative Example 1 was obtained in the same manner as in Example 1. <Fabrication of Die Bond Layer> A die bond layer according to Comparative Example 1 was obtained in the same manner as in Example 1. <Fabrication of Dicing Die Bond Film> Using the dicing tape according to Comparative Example 1 and the die bond layer according to Comparative Example 1, a dicing die bond film according to Comparative Example 1 was obtained.

[0117] [Comparative Example 2] <Synthesis of Acrylic Polymer> An acrylic polymer according to Comparative Example 2 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer had the blending ratio shown in Table 1 below. <Preparation of Adhesive Solution> An adhesive solution according to Comparative Example 2 was obtained in the same manner as in Example 1, except that the acrylic polymer according to Comparative Example 2 was used and the crosslinking agent (Coronate L) had the blending ratio shown in Table 1 below. <Preparation of Dicing Tape> A dicing tape according to Comparative Example 2 was obtained in the same manner as in Example 1 using the adhesive solution according to Comparative Example 2. <Preparation of Die Bond Layer> A die bond layer according to Comparative Example 2 was obtained in the same manner as in Example 1. <Preparation of Dicing Die Bond Film> A dicing die bond film according to Comparative Example 2 was obtained using the dicing tape according to Comparative Example 2 and the die bond layer according to Comparative Example 2.

[0118] [Comparative Example 3] <Synthesis of Acrylic Polymer> An acrylic polymer according to Comparative Example 3 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer had the blending ratio shown in Table 1 below. <Preparation of Adhesive Solution> An adhesive solution according to Comparative Example 3 was obtained in the same manner as in Example 1, except that the acrylic polymer according to Comparative Example 3 was used and the crosslinking agent (Coronate L) had the blending ratio shown in Table 1 below. <Preparation of Dicing Tape> A dicing tape according to Comparative Example 3 was obtained in the same manner as in Example 1 using the adhesive solution according to Comparative Example 3. <Preparation of Die Bond Layer> A die bond layer according to Comparative Example 3 was obtained in the same manner as in Example 1. <Preparation of Dicing Die Bond Film> A dicing die bond film according to Comparative Example 3 was obtained using the dicing tape according to Comparative Example 3 and the die bond layer according to Comparative Example 3.

[0119] [Comparative Example 4] <Synthesis of Acrylic Polymer> An acrylic polymer according to Comparative Example 4 was obtained in the same manner as in Example 1, except that the (meth)acrylic monomer was used in the blending ratio shown in Table 1 below. <Preparation of Adhesive Solution> An adhesive solution according to Comparative Example 4 was obtained in the same manner as in Example 1, except that the acrylic polymer according to Comparative Example 4 was used, Omnirad 184 was used as a photoinitiator, and the crosslinking agent (Coronate L) was used in the blending ratio shown in Table 1 below. Note that Omnirad 184 is also a product manufactured by IGM Resins. <Preparation of Dicing Tape> A dicing tape according to Comparative Example 4 was obtained in the same manner as in Example 1, using the adhesive solution according to Comparative Example 4. <Preparation of Die Bond Layer> A die bond layer according to Comparative Example 4 was obtained in the same manner as in Example 1. <Preparation of Dicing Die Bond Film> A dicing die bond film according to Comparative Example 4 was obtained using the dicing tape according to Comparative Example 4 and the die bond layer according to Comparative Example 4.

[0120] In Table 1 below, LA means lauryl acrylate (alkyl (meth)acrylate having an alkyl group with 12 or more carbon atoms), INA means isononyl acrylate (alkyl (meth)acrylate having an alkyl group with 9 or more carbon atoms), 2EHA means 2-ethylhexyl acrylate, BA means butyl acrylate, EA means ethyl acrylate, ACMO means 4-acryloylmorpholine, and HEA means 2-hydroxyethyl acrylate (hydroxyl group-containing (meth)acrylate).

[0121]

Table 1

[0122] (Glass Transition Temperature Tg) Regarding the dicing die bond film according to each example, the glass transition temperature Tg of the acrylic polymer contained in the adhesive layer 2 was determined. The glass transition temperature Tg of the acrylic polymer contained in the adhesive layer 2 was calculated using the FOX's equation represented by the following formula (1).

[0123]

Equation

[0124] Regarding the glass transition temperature of the homopolymer of LA, the glass transition temperature of the homopolymer of 2EHA, the glass transition temperature of the homopolymer of BA, and the glass transition temperature of the homopolymer of EA, the values described in the above-mentioned "Polymer Handbook" were used. In the "Polymer Handbook", 270K is described as the glass transition temperature of the homopolymer of LA, 223K is described as the glass transition temperature of the homopolymer of 2HEA, 219K is described as the glass transition temperature of the homopolymer of BA, and 249K is described as the glass transition temperature of the homopolymer of EA. Also, as the glass transition temperature of the homopolymer of INA, -58°C (215K) described in the catalog of Osaka Organic Chemical Industry Co., Ltd. was used, as the glass transition temperature of the homopolymer of ACMO, 145°C (418K) described in the catalog of KJ Chemical Co., Ltd. was used, and as the glass transition temperature of the homopolymer of HEA, -15°C (258K) described in the catalog of Kyoeisha Chemical Co., Ltd. was used. Note that as described in the section of the embodiment, since MOI is a substance that undergoes addition polymerization to the functional group of HEA, it is considered that the influence on the glass transition temperature of the copolymer is small. Therefore, in the calculation of the glass transition temperature using FOX's equation, the value of the glass transition temperature of the homopolymer of MOI was not adopted.

[0125] In each example, the mass fraction of the alkyl (meth) acrylate was calculated from the molecular weight and molar fraction of each alkyl (meth) acrylate monomer. For each example, the calculated results of the mass fraction of the alkyl (meth) acrylate are shown in Table 2 below.

[0126] [Table 2]

[0127] For the dicing die bond film according to each example, the glass transition temperature Tg of the acrylic polymer calculated using the FOX equation is shown in Table 3 below.

[0128] (Shear storage modulus of the adhesive layer at a temperature of -15°C) For the dicing die bond film according to each example, the shear storage modulus of the adhesive layer at a temperature of -15°C was measured according to the method described in the section of the embodiment. The results are shown in Table 3 below.

[0129] (Crack elongation rate) The crack elongation rate was measured for the dicing die bond film according to each example. The crack elongation rate was measured for the dicing tape according to each example using a tensile tester (a tensile tester with a thermostat manufactured by Shimadzu Corporation). Specifically, the measurement was performed as follows. (1) Cut the dicing tape according to each example into test pieces with a width of 10 mm and a length of 200 mm. (2) Using a tensile tester (a tensile tester with a thermostat manufactured by Shimadzu Corporation), stretch it by 250% at a chuck distance of 50 mm, a temperature of -15°C, and a tensile speed of 1000 mm / min. (3) When a crack occurs in the adhesive layer, the value of the elongation rate at the time of the crack occurrence is measured as the crack elongation rate. On the other hand, if no crack occurs in the adhesive layer even after stretching by 250%, it is evaluated as no crack. The results are shown in Table 3 below. Note that "no cracking occurred" means that when the above test was conducted to obtain data on strain (tensile length) and tensile strength, and a graph was drawn with the strain (tensile length) on the horizontal axis and the tensile strength on the vertical axis, the instantaneous decrease in tensile strength was less than 3%. That is, it does not mean that a decrease in tensile strength of less than 3% occurs continuously.

[0130] (Thickness) For the dicing die bond film according to each example, the thickness of the dicing tape was measured according to the method described in the section on the embodiment. The results are shown in Table 3 below.

[0131] (Peel strength) For the dicing die bond film according to each example, the peel strength of the dicing tape was measured according to the method described in the section on the embodiment. The results are shown in Table 3 below.

[0132] (25% Tensile strength) For the dicing die bond film according to each example, the 25% tensile strength of the dicing tape was measured according to the method described in the section on the embodiment. The results are shown in Table 3 below.

[0133] (Evaluation of cracking and kerf width) For the dicing die bond film according to each example, the cracking of the adhesive layer 2 and the kerf width (width between the diced bond layers) were evaluated. When evaluating the cracking and kerf width, first, a specimen was prepared according to the following procedure. (1) For a 12-inch bare wafer (diameter 300 mm, thickness 55 μm) with a dividing groove (10 mm × 10 mm) formed by half-cutting, a back grind tape is attached to the surface on which the dividing groove is formed. (2) Using a back grinder (manufactured by DISCO, model DGP8760), grind the 12-inch bare wafer from the side opposite to the side where the back grind tape is attached to a thickness of 25 μm to obtain a backgrounded bare wafer. (3) Attach the die bond layer of the dicing die bond film according to each example to the side opposite to the attachment surface of the back grind tape on the backgrounded bare wafer to obtain a bare wafer with a dicing die bond film, that is, a specimen for evaluating the crack and kerf width.

[0134] Regarding the specimen obtained as described above, expansion was performed using a die separator device (trade name "Die Separator DDS3200", manufactured by DISCO) to evaluate the crack and kerf width. The expansion using the die separator device was performed by performing room temperature expansion after performing cool expansion. Specifically, expansion was performed as follows. (1) Using a cool expander unit, expand the specimen under the conditions of an expansion temperature of -15°C, an expansion speed of 200 mm / second, and an expansion amount of 15 mm to cut the semiconductor wafer (bare wafer) and the die bond layer to obtain a semiconductor chip with a die bond layer (bare chip). (2) Further expand the specimen under the conditions of room temperature (23 ± 3°), an expansion speed of 1 mm / second, and an expansion amount of 7 mm. (3) While maintaining the expanded state, thermally shrink the dicing die bond film at the boundary portion with the outer peripheral edge of the semiconductor wafer (bare wafer) under the conditions of a heat temperature of 250°C, a heat distance of 20 mm, and a rotation speed of 5° / second.

[0135] Regarding the evaluation of the crack and kerf width, observation was performed on 9 regions of the specimen after expansion at magnifications of 200 times or 500 times using a confocal laser microscope. Specifically explaining with reference to Fig. 8, as the observation region by the confocal laser microscope, the region C at the center of the expanded specimen S, and the regions near the edges of the specimen S along the virtual line segments L1 to L8 obtained by dividing the expanded specimen S into eight equal sectors (divided so that the central angle is 45°) (the region from 5 mm or more to 30 mm or less from the edge of the specimen S) are designated as EP1 to EP8. Note that although the specimen S is cut by expansion, in Fig. 8, the cut line is not shown (the cut line is omitted). The evaluation of the crack and the kerf width was specifically performed as follows. ·Evaluation of the kerf width (1) While observing the nine regions of the specimen with a microscope (magnification 200 times or 500 times), for all between the bare chips, the minimum value W of the kerf width min is obtained. (2) If all of the minimum values W of the kerf width min are equal to or greater than the value of the blade width W of the dicing blade used for the half-cut when obtaining the specimen B , it is judged as qualified. On the other hand, if there is even one value of the minimum value W of the kerf width min that is less than the value of the blade width W B , it is judged as unqualified. ·Evaluation of the crack Regarding the region including the location where the curve width is maximum among the nine regions of the specimen, after peeling the bare chip and the die bond layer 3, the presence or absence of cracks is evaluated by visually observing the exposed adhesive layer 2 using a confocal laser microscope. The results of evaluating the crack and the kerf width are shown in Table 3 below.

[0136]

Table 3

[0137] From Table 3, it can be seen that in the dicing die bond films according to Examples 1 to 7, no cracks were confirmed in the adhesive layer after expansion. In addition, in the dicing die bond films according to Examples 1 to 7, it can be seen that after expansion, the kerf width reaches a qualified level. On the other hand, in the dicing die bond films according to Comparative Examples 1 to 4, cracks were confirmed in the adhesive layer after expansion, and it can be seen that the kerf width reaches a non - qualified level.

[0138] From these results, in the dicing die bond film, after making the acrylic polymer contained in the adhesive layer contain 15 mol% or more of the structural unit of alkyl acrylate having an alkyl group with 9 or more carbon atoms, the shear storage modulus of the adhesive layer at - 15°C is set to 10 MPa or less, and further, as the acrylic polymer, by using one having a glass transition temperature calculated using the FOX equation of - 47°C or more and 5°C or less, it can be seen that the occurrence of cracks in the adhesive layer can be suppressed in the expansion process. In addition, it can be seen that by suppressing the occurrence of cracks in the adhesive layer, the kerf width can be maintained uniformly.

Explanation of symbols

[0139] 1 Substrate layer 2 Adhesive layer 3 Die bond layer 10 Dicing tape 20 Dicing die bond film C Region of the central part EP1 - EP8 Regions near the edge G Back - grinding tape H Holder J Adsorption jig L1 - L8 Virtual line segments P Pin member R Dicing ring S Specimen T Tape for wafer processing U Pushing - up member W Semiconductor wafer

Claims

1. A dicing tape having an adhesive layer laminated on a base material layer, and a die bond layer laminated on the adhesive layer of the dicing tape, wherein the adhesive layer contains an acrylic polymer, the acrylic polymer contains 15 mol% or more of a structural unit of an alkyl (meth)acrylate having an alkyl group with 9 or more carbon atoms, the shear storage modulus of the adhesive layer at a temperature of -15°C is 10 MPa or less, the glass transition temperature of the acrylic polymer calculated using the FOX equation is -36.6°C or more and 5°C or less a dicing die bond film.

2. The thickness of the dicing tape is 50 μm or more and 250 μm or less The dicing die bond film according to Claim 1.

3. The 25% tensile strength of the dicing tape is 2 N / 10 mm or more and 50 N / 10 mm or less The dicing die bond film according to Claim 1 or 2.

4. The 180° peel strength between the base material layer and the adhesive layer is 1.0 N / 20 mm or more at room temperature The dicing die bond film according to any one of Claims 1 to 3.

5. The acrylic polymer contains a structural unit of an alkyl (meth)acrylate having an alkyl group with 9 or more carbon atoms and a structural unit of a hydroxyl group-containing (meth)acrylate, the hydroxyl group-containing (meth)acrylate is contained in less than 40 mol% The dicing die bond film according to any one of Claims 1 to 4.

6. When the dicing tape is stretched 200% at a tensile speed of 1000 mm / min at a temperature of -15°C, no crack occurs in the adhesive layer The dicing die bond film according to any one of Claims 1 to 5.

7. Used for dicing a semiconductor wafer The dicing die bond film according to any one of Claims 1 to 6.

Images