JP6312498B2 - Dicing film, dicing die-bonding film, and semiconductor device manufacturing method - Google Patents

Description

  The present invention relates to a dicing film, a dicing die bond film, and a method for manufacturing a semiconductor device.

  2. Description of the Related Art Conventionally, in a semiconductor device manufacturing process, a dicing die-bonding film has been proposed that adheres and holds a semiconductor wafer in a dicing process and also provides an adhesive layer for chip fixation necessary for a mounting process (for example, Patent Documents). 1). This dicing die-bonding film is obtained by providing an adhesive layer on a dicing film having a supporting base and an adhesive layer, and dicing the semiconductor wafer with a blade while holding the adhesive layer (so-called blade dicing). ) And then expanding the dicing film in the expanding step, and then picking up the separated chips together with the adhesive layer, individually collecting them and attaching the adherend such as a lead frame through the adhesive layer. It is made to adhere to.

  On the other hand, in recent years, a semiconductor wafer can be easily divided on the planned division line by irradiating a laser beam onto the planned division line of the semiconductor wafer to form a modified region, and then this semiconductor is applied by applying a tensile stress. There has been proposed a method of breaking individual wafers to obtain individual semiconductor chips (hereinafter also referred to as “stealth dicing (registered trademark)”) (see, for example, Patent Documents 2 and 3). According to these methods, the occurrence of defects such as chipping can be reduced even with a thin semiconductor wafer, and the kerf width (cut white) is made narrower than before to improve the yield of semiconductor chips. It is supposed to be possible.

JP 2008-218571 A JP 2002-192370 A JP 2003-338467 A

  In order to obtain individual semiconductor chips with a die bond film by stealth dicing while holding the dicing die bond film, it is necessary to break the die bond film together with the semiconductor wafer by the tensile stress in the expanding process. However, actually, the tensile stress is not applied only to the die bond film, but in particular, the tensile stress is applied to the dicing film to elongate the film to induce breakage of the die bond film.

  In stealth dicing, a technique of expanding at a low temperature (for example, 0 ° C.) is being proposed in order to improve the breakability of the die bond film. However, when the dicing film in the conventional dicing die-bonding film is expanded at a low temperature, there is a problem that the semiconductor wafer and the die-bonding film are not partially broken, resulting in a decrease in the manufacturing yield of the semiconductor device. Yes.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to provide a dicing film capable of inducing breakage of a semiconductor wafer or a die bond film even when expanded at a low temperature, a dicing die bond film including the dicing film, and these films. It is an object of the present invention to provide a method of manufacturing a semiconductor device using

  As a result of intensive studies to solve the above problems, the inventors of the present application have anisotropy in characteristics (hereinafter also referred to as “tensile characteristics”) when a tensile stress is applied to a dicing film or a dicing die bond film. As a result, it was found that the die bond film and the semiconductor wafer were suitably broken by the tensile stress by suppressing this, and the present invention was completed.

That is, the present invention is a dicing film comprising a substrate and a pressure-sensitive adhesive layer provided on the substrate,
The tensile elastic modulus in the MD direction obtained from the stress-strain curve when a tensile stress is applied at 0 ° C. in each of the MD direction and the TD direction is _E′MD1, and the tensile elastic modulus in the TD direction is _E′TD1 . When it does, it is related with the dicing film whose _E'MD1 / _E'TD1 is 0.75 or more and 1.25 or less.

  The inventors of the present application paid attention to the anisotropy of the tensile properties, in particular, the anisotropy of the substrate responsible for the mechanical strength of the dicing film. Film bases (typically olefinic films) used for dicing films are often given anisotropy in manufacturing processes such as extrusion and stretching, and are handled in a roll form, so that the winding tension In some cases, tensile stress is generated due to, for example, anisotropy. Furthermore, when manufacturing a dicing die-bonding film, the die-bonding film formed on the separator may be bonded together on the long dicing film being conveyed, and both may be integrated. If the tension in this bonding process is high, stress is also generated thereby, and anisotropy occurs.

  In the expanding process, the entire outer periphery of the dicing film is pulled in the radial direction to apply a tensile stress, but the dicing film obtained using an anisotropic base material does not have uniform in-plane tensile properties. As a result, the semiconductor wafer or die bond film is not sufficiently broken. In particular, such anisotropy tends to become remarkable at a low temperature of 0 ° C.

The dicing in the film, 0 ratio of _TD1 'tensile modulus E at _MD1 and TD direction' tensile modulus E of the tensile MD direction during stress loading in ° C. (E _'MD1 / E' _TD1, hereinafter, "different It is also referred to as an “orientation ratio 1”.) Is 0.75 or more and 1.25 or less. In other words, the anisotropy of the tensile elastic modulus, which is one of the tensile properties, is suppressed, and the in-plane tensile properties are made as isotropic as possible. Thereby, the tensile stress at the time of expansion is uniformly applied to the surface of the dicing film, and the dicing film is uniformly stretched in the radial direction, so that sufficient breakage of the die bond film and the semiconductor wafer can be induced. . If the upper limit and the lower limit of the anisotropy ratio 1 are deviated, in either case, the anisotropy of the tensile properties of the dicing film becomes obvious and may not lead to sufficient breakage.

In the present specification, the MD direction is the flow direction of the substrate, and the TD direction is a direction perpendicular to the MD direction. Moreover, the measuring method of each tensile elasticity modulus is based on description of an Example.

In the dicing film, the absolute value of the difference between the tensile elastic modulus E ′ _MD1 and the tensile elastic modulus E ′ _TD1 is preferably 1 MPa or more and 50 MPa or less. By setting the absolute value of the difference in tensile modulus within the above range, the tensile characteristics of the dicing film can be made more uniform.

In the dicing film, it is preferable that at least one of the tensile elastic modulus E ′ _MD1 and the tensile elastic modulus E ′ _TD1 is 10 MPa or more and 100 MPa or less. As a result, inadvertent breakage of the dicing film at a low temperature can be prevented, and the dicing film can be satisfactorily stretched even at a low temperature to induce sufficient breakage of the die bond film and the semiconductor wafer.

  The present invention also includes a dicing die-bonding film including the dicing film and a thermosetting die-bonding film provided on the pressure-sensitive adhesive layer of the dicing film. Thereby, the processes from dicing the semiconductor wafer to picking up the semiconductor element and mounting the semiconductor element can be efficiently performed as a series of flows.

  In the dicing die-bonding film, the peeling force at 0 ° C. between the pressure-sensitive adhesive layer and the thermosetting die-bonding film is greater than the peeling force at 23 ° C. between the pressure-sensitive adhesive layer and the thermosetting die-bonding film. Is preferably high. Thereby, the holding power of the semiconductor wafer or the semiconductor element at the time of dicing and the peelability of the chip with the die bond film at the time of pick-up can be balanced appropriately.

  In the dicing die-bonding film, it is preferable that the peeling force at 0 ° C. between the pressure-sensitive adhesive layer and the thermosetting die-bonding film is 0.15 N / 100 mm or more and 5 N / 100 mm or less. If the peeling force between the dicing film and the die bond film is weak, peeling occurs at the interface between the die bond film and the dicing film at the time of expansion. The peeling force at is preferably 0.15 N / 100 mm or more. On the other hand, if the peel force is too high, failure to break may occur, and it is preferably 5 N / 100 mm or less. In addition, in this specification, the measuring method of each peeling force is based on description of an Example.

  In the dicing die-bonding film, the peel force at 23 ° C. between the pressure-sensitive adhesive layer and the thermosetting die-bonding film is preferably 0.05 N / 100 mm or more and 2.5 N / 100 mm or less. In order to pick up a semiconductor element with a die-bonding film from a dicing film at room temperature (23 ± 2 ° C.), it is preferable to have a light peelability. In particular, stealth dicing semiconductor wafers are thinner than blade dicing and are more likely to break, and therefore further reduction in peel strength is required. When the peeling force is 2.5 N / 100 mm or less, good light peelability can be exhibited. On the other hand, when the peeling force is lower than 0.05 N / 100 mm, it may be difficult to hold the semiconductor element during transportation. In addition, when the pressure-sensitive adhesive layer is a type in which the adhesive strength is reduced by ultraviolet irradiation, the peeling force after the ultraviolet irradiation may be in the above range.

  The dicing die bond film is suitable for a semiconductor element manufacturing method for obtaining a semiconductor element by irradiating a semiconductor wafer with laser light to form a modified region and then breaking the semiconductor wafer at the modified region. Used.

In the present invention, a step of irradiating a laser wafer to a division line of a semiconductor wafer to form a modified region along the division line,
Bonding the semiconductor wafer after the modified region formation to the dicing die-bonding film;
By applying tensile stress to the dicing die-bonding film under the condition of −20 ° C. to 15 ° C., the semiconductor wafer and the die-bonding film of the dicing die-bonding film are ruptured along the scheduled dividing line. Forming a step;
Picking up the semiconductor element together with the die bond film;
And a step of die-bonding the picked-up semiconductor element to an adherend via the die-bonding film.

  In the manufacturing method, since the semiconductor wafer is ruptured by stealth dicing using a dicing die-bonding film in which anisotropy of tensile properties is suppressed, sufficient rupture of the die-bonding film and the semiconductor wafer in an expanding process in which tensile stress is applied. Can be induced, and defects such as chipping of the semiconductor element can be prevented to improve manufacturing efficiency.

It is a cross-sectional schematic diagram which shows the dicing die-bonding film which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows the dicing die-bonding film which concerns on other embodiment of this invention. It is a cross-sectional schematic diagram for demonstrating one manufacturing method of the semiconductor device which concerns on this embodiment. It is a cross-sectional schematic diagram for demonstrating one manufacturing method of the semiconductor device which concerns on this embodiment. (A), (b) is a cross-sectional schematic diagram for demonstrating one manufacturing method of the semiconductor device which concerns on this embodiment. It is a cross-sectional schematic diagram for demonstrating one manufacturing method of the semiconductor device which concerns on this embodiment.

<Dicing die bond film>
The dicing die bond film of the present invention will be described below. FIG. 1 is a schematic cross-sectional view showing a dicing die-bonding film according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing a dicing die-bonding film according to another embodiment of the present invention.

  As shown in FIG. 1, the dicing die bond film 10 has a configuration in which a die bond film 3 is laminated on a dicing film 11. The dicing film 11 is configured by laminating the pressure-sensitive adhesive layer 2 on the base material 1, and the die-bonding film 3 is provided on the pressure-sensitive adhesive layer 2. Further, the present invention may have a configuration in which a die bond film 3 'is formed only on a semiconductor wafer bonding portion, like a dicing die bond film 12 shown in FIG.

(Dicing film)
In the dicing film 11, the tensile elastic modulus in the MD direction obtained from a stress-strain curve obtained by applying a tensile stress at 0 ° C. in each of the MD direction and the TD direction is _E′MD1, and the tensile elastic modulus in the TD direction is 'If the _TD1, E' E the _MD1 / E _'TD1 is 0.75 to 1.25. The lower limit of the ratio (anisotropy ratio 1) _E′MD1 / _E′TD1 is preferably 0.78 or more. On the other hand, the upper limit of the anisotropy ratio 1 is preferably 1.20 or less, more preferably 1.17 or less. By setting the anisotropy ratio 1 of the dicing film 11 within the above range, the tensile stress during expansion is uniformly applied to the surface of the dicing film, and the dicing film is uniformly stretched in the radial direction. Sufficient breakage of the film and semiconductor wafer can be induced.

(Base material)
The base material 1 preferably has ultraviolet transparency, and serves as a strength matrix for the dicing die bond films 10 and 12. For example, polyolefins such as low density polyethylene, linear polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolyprolene, polybutene, polymethylpentene, ethylene-acetic acid Vinyl copolymer, ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, Polyester such as polyurethane, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyetheretherketone, polyimide, polyetherimide, polyamide, wholly aromatic polyamide, polyphenylsulfur De, aramid (paper), glass, glass cloth, fluorine resin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, silicone resin, metal (foil), paper, and the like. Moreover, polymers, such as the crosslinked body of the said resin, are mentioned.

  The resin film is easily imparted with anisotropy in the production process. Since the substrate bears the mechanical strength of the dicing film, it strongly affects the anisotropy of the tensile properties of the dicing film. Therefore, it is preferable that the anisotropy of the resin film itself as a base material is suppressed. Although there is no particular limitation on the method for relaxing the anisotropy of the resin film, for example, a resin film formed by a solution casting method is used, heat treatment is performed to the extent that stress remaining in the resin film can be reduced, or the resin film In order to prevent stress from being applied, it is possible to reduce the winding tension as much as possible without performing a stretching or rolling process. As long as the anisotropy of the tensile property of a dicing film can be suppressed, the resin film may be used without stretching, or may be subjected to uniaxial or biaxial stretching treatment as necessary.

  The surface of the substrate 1 is chemically treated by conventional surface treatments such as chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, ionizing radiation treatment, etc. in order to improve adhesion and retention with adjacent layers. Alternatively, a physical treatment or a coating treatment with a primer (for example, an adhesive substance described later) can be performed. The base material 1 can be used by appropriately selecting the same kind or different kinds, and a blend of several kinds can be used as necessary. Further, in order to impart antistatic ability to the base material 1, a conductive material vapor deposition layer having a thickness of about 30 to 500 mm made of metal, alloy, oxides thereof, or the like is provided on the base material 1. be able to. The substrate 1 may be a single layer or two or more types.

  The thickness of the substrate 1 is not particularly limited and can be appropriately determined, but is generally about 5 to 200 μm.

(Adhesive layer)
The pressure-sensitive adhesive layer 2 includes an ultraviolet curable pressure-sensitive adhesive. The UV curable pressure-sensitive adhesive can easily reduce its adhesive strength by increasing the degree of crosslinking by irradiation of ultraviolet light, and only the portion 2a corresponding to the semiconductor wafer attachment portion of the pressure-sensitive adhesive layer 2 shown in FIG. By irradiating with ultraviolet rays, a difference in adhesive strength with the other portion 2b can be provided.

  Further, by curing the ultraviolet curable pressure-sensitive adhesive layer 2 in accordance with the die-bonding film 3 ′ shown in FIG. 2, the portion 2 a having a significantly reduced adhesive force can be easily formed. Since the die bond film 3 ′ is attached to the portion 2 a that has been cured and has reduced adhesive strength, the interface between the portion 2 a and the die bond film 3 ′ of the pressure-sensitive adhesive layer 2 has a property of being easily peeled off during pick-up. On the other hand, the portion not irradiated with ultraviolet rays has a sufficient adhesive force, and forms the portion 2b.

  As described above, in the pressure-sensitive adhesive layer 2 of the dicing die-bonding film 10 shown in FIG. 1, the portion 2b formed of the uncured ultraviolet-curing pressure-sensitive adhesive adheres to the die-bonding film 3 and is used when dicing. A holding force can be secured. In this way, the ultraviolet curable pressure-sensitive adhesive can support the die bond film 3 for die-bonding a semiconductor chip to an adherend such as a substrate with a good balance of adhesion and peeling. In the pressure-sensitive adhesive layer 2 of the dicing die-bonding film 12 shown in FIG. 2, the portion 2b can fix the wafer ring.

  As the ultraviolet curable pressure-sensitive adhesive, those having an ultraviolet curable functional group such as a carbon-carbon double bond and exhibiting adhesiveness can be used without particular limitation. Examples of the ultraviolet curable pressure-sensitive adhesive include an additive-type ultraviolet curable pressure-sensitive adhesive in which an ultraviolet curable monomer component or an oligomer component is blended with a general pressure-sensitive adhesive such as an acrylic pressure-sensitive adhesive or a rubber-based pressure-sensitive adhesive. Can be illustrated.

  As the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive having an acrylic polymer as a base polymer from the viewpoint of cleanability with an organic solvent such as ultrapure water or alcohol of an electronic component that is difficult to contaminate a semiconductor wafer or glass Is preferred.

  Examples of the acrylic polymer include (meth) acrylic acid alkyl esters (for example, methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, Isopentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester, tridecyl ester, tetradecyl ester, hexadecyl ester , Octadecyl esters, eicosyl esters, etc., alkyl groups having 1 to 30 carbon atoms, especially 4 to 18 carbon linear or branched alkyl esters, etc.) and Meth) acrylic acid cycloalkyl esters (e.g., cyclopentyl ester, acrylic polymers such as one or more was used as a monomer component of the cyclohexyl ester etc.). In addition, (meth) acrylic acid ester means acrylic acid ester and / or methacrylic acid ester, and (meth) of the present invention has the same meaning.

The acrylic polymer contains units corresponding to other monomer components copolymerizable with the (meth) acrylic acid alkyl ester or cycloalkyl ester, if necessary, for the purpose of modifying cohesive force, heat resistance and the like. You may go out. Examples of such monomer components include, for example, carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride Acid anhydride monomers such as itaconic anhydride; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate , 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate,
Hydroxyl group-containing monomers such as (meth) acrylic acid 12-hydroxylauryl, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate; styrenesulfonic acid, allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid Sulfonic acid group-containing monomers such as (meth) acrylamide propanesulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalene sulfonic acid; phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate; acrylamide, acrylonitrile, etc. Is mentioned. One or more of these copolymerizable monomer components can be used. The amount of these copolymerizable monomers used is preferably 40% by weight or less based on the total monomer components.

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

  The acrylic polymer can be obtained by subjecting a single monomer or a mixture of two or more monomers to polymerization. The polymerization can be performed by any method such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization and the like. From the viewpoint of preventing contamination of a clean adherend, the content of the low molecular weight substance is preferably small. From this point, the number average molecular weight of the acrylic polymer is preferably 300,000 or more, more preferably about 400,000 to 3,000,000.

  In addition, an external cross-linking agent can be appropriately employed for the pressure-sensitive adhesive in order to increase the number average molecular weight of an acrylic polymer as a base polymer. Specific examples of the external crosslinking method include a method of adding a so-called crosslinking agent such as a polyisocyanate compound, an epoxy compound, an aziridine compound, a melamine crosslinking agent, and reacting them. When using an external cross-linking agent, the amount used is appropriately determined depending on the balance with the base polymer to be cross-linked and further depending on the intended use as an adhesive. Generally, 5 parts by weight or less is preferable with respect to 100 parts by weight of the base polymer. Moreover, it is preferable that it is 0.1 weight part or more as a lower limit. Furthermore, additives such as various tackifiers and anti-aging agents may be used for the adhesive, if necessary, in addition to the above components.

  Examples of the ultraviolet curable monomer component to be blended include urethane oligomer, urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, pentaerythritol tri (meth) acrylate, and penta. Examples include erythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, and the like. Examples of the ultraviolet curable oligomer component include urethane, polyether, polyester, polycarbonate, and polybutadiene oligomers, and those having a molecular weight in the range of about 100 to 30000 are suitable. The blending amount of the ultraviolet curable monomer component and oligomer component can be appropriately determined in accordance with the type of the pressure-sensitive adhesive layer, and the amount capable of reducing the pressure-sensitive adhesive strength of the pressure-sensitive adhesive layer. Generally, the amount is, for example, about 5 to 500 parts by weight, preferably about 70 to 150 parts by weight with respect to 100 parts by weight of the base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

  In addition to the additive-type UV-curable pressure-sensitive adhesive described above, the UV-curable pressure-sensitive adhesive has a carbon-carbon double bond in the polymer side chain, main chain, or main chain terminal as a base polymer. Intrinsic ultraviolet curable pressure sensitive adhesives using Intrinsic UV curable pressure-sensitive adhesive does not need to contain an oligomer component or the like, which is a low molecular weight component, or does not contain much, so that the oligomer component or the like does not move through the pressure-sensitive adhesive over time and is stable. It is preferable because an adhesive layer having a layer structure can be formed.

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

  The method for introducing the carbon-carbon double bond into the acrylic polymer is not particularly limited, and various methods can be adopted. However, the carbon-carbon double bond can be easily introduced into the polymer side chain for easy molecular design. . For example, after a monomer having a functional group is previously copolymerized with an acrylic polymer, a compound having a functional group capable of reacting with the functional group and a carbon-carbon double bond is converted into an ultraviolet curable carbon-carbon double bond. A method of performing condensation or addition reaction while maintaining the above.

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

As the intrinsic ultraviolet curable pressure-sensitive adhesive, the base polymer (particularly acrylic polymer) having the carbon-carbon double bond can be used alone, but the ultraviolet curable monomer does not deteriorate the characteristics. Components and oligomer components can also be blended. The UV-curable oligomer component or the like is usually in the range of 30 parts by weight, preferably in the range of 0 to 10 parts by weight with respect to 100 parts by weight of the base polymer.

The ultraviolet curable pressure-sensitive adhesive contains a photopolymerization initiator when cured by ultraviolet rays or the like. Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α′-dimethylacetophenone, 2-methyl-2-hydroxypropio Α-ketol compounds such as phenone and 1-hydroxycyclohexyl phenyl ketone; methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1-
Acetophenone compounds such as [4- (methylthio) -phenyl] -2-morpholinopropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether and anisoin methyl ether; ketal compounds such as benzyldimethyl ketal; Aromatic sulfonyl chloride compounds such as 2-naphthalenesulfonyl chloride; photoactive oxime compounds such as 1-phenone-1,1-propanedione-2- (o-ethoxycarbonyl) oxime; benzophenone, benzoylbenzoic acid, 3, Benzophenone compounds such as 3′-dimethyl-4-methoxybenzophenone; thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4- Examples include thioxanthone compounds such as dichlorothioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone; camphorquinone; halogenated ketone; acyl phosphinoxide; acyl phosphonate. The compounding quantity of a photoinitiator is about 0.05-20 weight part with respect to 100 weight part of base polymers, such as an acryl-type polymer which comprises an adhesive.

  Examples of the ultraviolet curable pressure-sensitive adhesive include photopolymerizable compounds such as addition polymerizable compounds having two or more unsaturated bonds and alkoxysilanes having an epoxy group disclosed in JP-A-60-196956. And a rubber-based pressure-sensitive adhesive and an acrylic pressure-sensitive adhesive containing a photopolymerization initiator such as a carbonyl compound, an organic sulfur compound, a peroxide, an amine, and an onium salt-based compound.

  Examples of the method for forming the portion 2a on the pressure-sensitive adhesive layer 2 include a method in which after the ultraviolet curable pressure-sensitive adhesive layer 2 is formed on the substrate 1, the portion 2a is partially irradiated with ultraviolet rays to be cured. . The partial ultraviolet irradiation can be performed through a photomask on which a pattern corresponding to the portion 3b other than the semiconductor wafer bonding portion 3a is formed. Moreover, the method etc. of irradiating and hardening | curing an ultraviolet-ray spotly are mentioned. The ultraviolet curable pressure-sensitive adhesive layer 2 can be formed by transferring what is provided on the separator onto the substrate 1. Partial UV curing can also be performed on the UV curable pressure-sensitive adhesive layer 2 provided on the separator.

  In the pressure-sensitive adhesive layer 2 of the dicing die-bonding film 10, a part of the pressure-sensitive adhesive layer 2 is irradiated with ultraviolet rays so that (the adhesive strength of the portion 2a) <(the adhesive strength of the other portion 2b). Also good. That is, after forming the ultraviolet-curing pressure-sensitive adhesive layer 2 on the substrate 1, at least one side of the substrate 1 is shielded from all or part of the portion other than the portion corresponding to the semiconductor wafer pasting portion 3 a. By irradiating with ultraviolet rays, the portion corresponding to the semiconductor wafer pasting portion 3a can be cured to form the portion 2a with reduced adhesive strength. As the light shielding material, a material that can be a photomask on a support film can be produced by printing or vapor deposition. Thereby, the dicing die-bonding film 10 of this invention can be manufactured efficiently.

  The thickness of the pressure-sensitive adhesive layer 2 is not particularly limited, but is preferably about 1 to 50 μm, more preferably 2 to 30 μm, and still more preferably, from the viewpoint of chipping prevention of the chip cut surface and compatibility of fixing and holding of the adhesive layer. 5 to 25 μm.

In the dicing film 11, the absolute value of the difference between the tensile elastic modulus E ′ _MD1 and the tensile elastic modulus E ′ _TD1 is preferably 1 MPa or more and 50 MPa or less, and more preferably 3 MPa or more and 30 MPa or less. By setting the absolute value of the difference in tensile modulus within the above range, the tensile characteristics of the dicing film can be made more uniform.

In the dicing film 11, at least one of the tensile modulus E _'MD1 and the tensile modulus E' _TD1 is preferably at most 100MPa or more 10 MPa, and more preferably less than 20 MPa 90 MPa. As a result, inadvertent breakage of the dicing film at a low temperature can be prevented, and the dicing film can be satisfactorily stretched even at a low temperature to induce sufficient breakage of the die bond film and the semiconductor wafer.

(Die bond film)
The layer structure of the die bond film is not particularly limited. For example, a single bond layer or a single adhesive layer such as the die bond films 3 and 3 ′ (see FIGS. 1 and 2) is laminated. And a multilayer structure in which an adhesive layer is formed on one or both sides of the core material. Examples of the core material include a film (for example, a polyimide film, a polyester film, a polyethylene terephthalate film, a polyethylene naphthalate film, and a polycarbonate film), a resin substrate reinforced with glass fibers or plastic non-woven fibers, a silicon substrate, a glass substrate, or the like. Is mentioned .

  Examples of the adhesive composition constituting the die bond films 3 and 3 ′ include a combination of a thermoplastic resin and a thermosetting resin.

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

  The epoxy resin is not particularly limited as long as it is generally used as an adhesive composition, for example, 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 novolac type, orthocresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, etc., bifunctional epoxy resin or polyfunctional epoxy resin, or hydantoin type, trisglycidyl isocyanurate Type or glycidylamine type epoxy resin is used. These can be used alone or in combination of two or more. Of these epoxy resins, novolac type epoxy resins, biphenyl type epoxy resins, trishydroxyphenylmethane type resins or tetraphenylolethane type epoxy resins are particularly preferred. This is because these epoxy resins are rich in reactivity with a phenol resin as a curing agent and are excellent in heat resistance and the like.

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

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

  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, heat Examples thereof include plastic polyimide resins, polyamide resins such as 6-nylon and 6,6-nylon, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamideimide resins, and fluorine resins. These thermoplastic resins can be used alone or in combination of two or more. Of these thermoplastic resins, an acrylic resin that has few ionic impurities and high heat resistance and can ensure the reliability of the semiconductor element is particularly preferable.

  The acrylic resin is not particularly limited, and includes one or two or more esters of acrylic acid or methacrylic acid having a linear or branched alkyl group having 30 or less carbon atoms, particularly 4 to 18 carbon atoms. Examples thereof include a polymer (acrylic copolymer) as a component. Examples of the alkyl group include a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, heptyl group, cyclohexyl group, 2- Examples include an ethylhexyl group, an octyl group, an isooctyl group, a nonyl group, an isononyl group, a decyl group, an isodecyl group, an undecyl group, a lauryl group, a tridecyl group, a tetradecyl group, a stearyl group, an octadecyl group, and a dodecyl group.

  Among the acrylic resins, an acrylic copolymer is particularly preferable for the reason of improving cohesion. Examples of the acrylic copolymer include a copolymer of ethyl acrylate and methyl methacrylate, a copolymer of acrylic acid and acrylonitrile, and a copolymer of butyl acrylate and acrylonitrile.

  The glass transition temperature (Tg) of the acrylic resin is preferably −30 ° C. or higher and 30 ° C. or lower, and more preferably −20 or higher and 15 ° C. When the glass transition temperature of the acrylic resin is −30 ° C. or higher, the die bond film is hardened and breakability is improved, and when it is 30 ° C. or lower, the wafer laminating property at low temperature is improved. Examples of the acrylic resin having a glass transition temperature of −30 ° C. or higher and 30 ° C. or lower include Nagase ChemteX Corporation: SG-708-6 (glass transition temperature: 6 ° C.), SG-790 (glass transition temperature: − 25 ° C.), WS-023 (glass transition temperature: −5 ° C.), SG-80H (glass transition temperature: 7.5 ° C.), SG-P3 (glass transition temperature: 15 ° C.).

  In addition, the other monomer forming the polymer is not particularly limited, and examples thereof include acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Carboxyl group-containing monomers such as acid anhydride monomers such as maleic anhydride or itaconic anhydride, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4- (meth) acrylic acid 4- Hydroxybutyl, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate or (4-hydroxymethylcyclohexyl) -Methyla Hydroxyl group-containing monomers such as relate, styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate or (meth) Examples thereof include sulfonic acid group-containing monomers such as acryloyloxynaphthalene sulfonic acid, and phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate.

  The mixing ratio of the thermosetting resin is not particularly limited as long as the die-bonding films 3 and 3 ′ exhibit a function as a thermosetting type when heated under predetermined conditions. It is preferably within the range, and more preferably within the range of 10 to 50% by weight.

  The die bond films 3 and 3 ′ preferably have a glass transition temperature (Tg) before thermosetting of 25 to 60 ° C., more preferably 25 to 55 ° C., and further 25 to 50 ° C. preferable. By setting the glass transition temperature before thermosetting to 25 to 60 ° C., it becomes possible to laminate the wafer satisfactorily. In addition, the measurement of the glass transition temperature before thermosetting of a die-bonding film can be performed in the following procedures. That is, after a die-bonding film is piled up to a thickness of 100 μm under a condition of 40 ° C., the die-bonding film is cut so as to be a strip-shaped measurement piece having a width of 10 mm. Next, using a dynamic viscoelasticity measuring device (RSA (III), manufactured by Rheometric Scientific), loss tangent (tan δ) at −30 to 280 ° C. is a frequency of 10 Hz, and a temperature rising rate is 5 ° C./min. Measure under the following conditions. The glass transition temperature is determined from the peak value of tan δ at that time.

  Among the die-bonding films 3, 3 ′, when an epoxy resin, a phenol resin, and an acrylic resin are contained, the total weight of the epoxy resin and the phenol resin is X, and the weight of the acrylic resin is Y X / (X + Y) is preferably 0.3 or more and less than 0.9, more preferably 0.35 or more and less than 0.85, and further preferably 0.4 or more and less than 0.8. . While the epoxy resin and the phenol resin are easily broken as the content increases, the adhesion to the semiconductor wafer 4 decreases. In addition, as the content of the acrylic resin increases, the die-bonding films 3 and 3 ′ are less likely to be broken during bonding and handling, and the workability is improved. Therefore, by setting X / (X + Y) to 0.3 or more, when the semiconductor element 5 is obtained from the semiconductor wafer 4 by stealth dicing, the die bond films 3, 3 ′ and the semiconductor wafer 4 may be broken at the same time. It becomes easy. Moreover, workability | operativity can be made favorable by making X / (X + Y) less than 0.9.

  When the die-bonding films 3, 3 ′ of the present invention are previously crosslinked to some extent, a polyfunctional compound that reacts with a functional group at the molecular chain end of the polymer is added as a crosslinking agent in the production. Can do. Thereby, the adhesive property under high temperature can be improved and heat resistance can be improved.

  A conventionally well-known thing can be employ | adopted as said crosslinking agent. In particular, polyisocyanate compounds such as tolylene diisocyanate, diphenylmethane diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate, adducts of polyhydric alcohol and diisocyanate are more preferable. The addition amount of the crosslinking agent is usually preferably 0.05 to 7 parts by weight with respect to 100 parts by weight of the polymer. When the amount of the cross-linking agent is more than 7 parts by weight, the adhesive force is lowered, which is not preferable. On the other hand, if it is less than 0.05 parts by weight, the cohesive force is insufficient, which is not preferable. Moreover, you may make it include other polyfunctional compounds, such as an epoxy resin, together with such a polyisocyanate compound as needed.

  Moreover, a filler can be suitably mix | blended with die-bonding film 3, 3 'according to the use. The blending of the filler enables imparting conductivity, improving thermal conductivity, adjusting the elastic modulus, and the like. Examples of the filler include inorganic fillers and organic fillers, and inorganic fillers are preferable from the viewpoints of characteristics such as improvement in handleability, improvement in thermal conductivity, adjustment of melt viscosity, and imparting thixotropic properties. The inorganic filler is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, and aluminum borate whisker. , Boron nitride, crystalline silica, amorphous silica and the like. These can be used alone or in combination of two or more. From the viewpoint of improving thermal conductivity, aluminum oxide, aluminum nitride, boron nitride, crystalline silica, and amorphous silica are preferable. Further, from the viewpoint that the above properties are well balanced, crystalline silica or amorphous silica is preferable. In addition, a conductive substance (conductive filler) may be used as the inorganic filler for the purpose of imparting conductivity and improving thermal conductivity. Examples of the conductive filler include metal powder in which silver, aluminum, gold, cylinder, nickel, conductive alloy and the like are made into a spherical shape, needle shape and flake shape, metal oxide such as alumina, amorphous carbon black, graphite and the like.

  The average particle size of the filler is preferably 0.005 to 10 μm, and more preferably 0.005 to 1 μm. This is because when the average particle size of the filler is 0.005 μm or more, the wettability to the adherend and the adhesiveness can be improved. Moreover, by setting it as 10 micrometers or less, while being able to make the effect of the filler added for provision of said each characteristic sufficient, heat resistance can be ensured. In addition, the average particle diameter of a filler is the value calculated | required with the photometric type particle size distribution meter (The product made from HORIBA, apparatus name; LA-910).

  In the die bond film, when the total weight of the epoxy resin, the phenol resin, and the acrylic resin is A and the weight of the filler is B, B / (A + B) is 0.1 or more and 0.7 or less. Is preferably 0.1 or more and 0.65 or less, and more preferably 0.1 or more and 0.6 or less. By setting the above value to 0.7 or less, it is possible to prevent the tensile storage elastic modulus from increasing, and to improve the wettability and adhesion to the adherend. Moreover, a die-bonding film can be suitably fractured | ruptured with a tensile stress by making the said value into 0.1 or more.

  In addition to the said filler, other additives can be suitably mix | blended with the die-bonding films 3 and 3 'as needed. Examples of other additives include flame retardants, silane coupling agents, ion trapping agents, and the like. Examples of the flame retardant include antimony trioxide, antimony pentoxide, brominated epoxy resin, and the like. These can be used alone or in combination of two or more. Examples of the silane coupling agent include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and γ-glycidoxy. And propylmethyldiethoxysilane. These compounds can be used alone or in combination of two or more. Examples of the ion trapping agent include hydrotalcites and bismuth hydroxide. These can be used alone or in combination of two or more.

  Although the thickness (in the case of a laminated body) of die-bonding films 3 and 3 'is not specifically limited, For example, it can select from the range of 1-200 micrometers, Preferably it is 5-100 micrometers, More preferably, it is 10- 80 μm.

  The die bond films 3, 3 'of the dicing die bond films 10, 12 are preferably protected by a separator (not shown). The separator has a function as a protective material for protecting the die bond films 3 and 3 ′ until they are put into practical use. Further, the separator can be used as a support base material when transferring the die bond films 3 and 3 ′ to the pressure-sensitive adhesive layer 2. The separator is peeled off when a workpiece is stuck on the die bond film 3, 3 'of the dicing die bond film. As the separator, a plastic film or paper surface-coated with a release agent such as polyethylene terephthalate (PET), polyethylene, polypropylene, a fluorine release agent, or a long-chain alkyl acrylate release agent can be used.

  In the dicing die-bonding films 10 and 12, the peeling force at 0 ° C. between the pressure-sensitive adhesive layer and the thermosetting die-bonding film is peeling at 23 ° C. between the pressure-sensitive adhesive layer and the thermosetting die-bonding film. Preferably higher than the force. Thereby, the holding power of the semiconductor wafer or the semiconductor element at the time of dicing and the peelability of the chip with the die bond film at the time of pick-up can be balanced appropriately.

  In the dicing die bond films 10 and 12, the peel force at 0 ° C. between the pressure-sensitive adhesive layer and the thermosetting die bond film is preferably 0.15 N / 100 mm or more and 5 N / 100 mm or less, and 0.20 N / More preferably, it is 100 mm or more and 1 N / 100 mm or less. If the peeling force between the dicing film and the die bond film is weak, peeling occurs at the interface between the die bond film and the dicing film at the time of expansion. It is preferable that the peeling force in is not less than the above lower limit. On the other hand, if the peeling force is too high, failure to break may occur.

  In the dicing die-bonding films 10 and 12, the peeling force at 23 ° C. between the pressure-sensitive adhesive layer and the thermosetting die-bonding film is preferably 0.05 N / 100 mm or more and 2.5 N / 100 mm or less. More preferably, it is 10 N / 100 mm or more and 1 N / 100 mm or less. In order to pick up a semiconductor element with a die-bonding film from a dicing film at room temperature (23 ± 2 ° C.), it is preferable to have a light peelability. In particular, stealth dicing semiconductor wafers are thinner than blade dicing and are more likely to break, and therefore further reduction in peel strength is required. By making the peeling force below the above upper limit, good light peelability can be exhibited. On the other hand, if the peeling force is lower than the lower limit, it may be difficult to hold the semiconductor element during transportation. In addition, when the pressure-sensitive adhesive layer is a type in which the adhesive strength is reduced by ultraviolet irradiation, the peeling force after the ultraviolet irradiation may be in the above range.

<Manufacturing method of dicing die bond film>
The dicing die bond films 10 and 12 according to the present embodiment are produced as follows, for example.
First, the base material 1 can be formed by a conventionally known film forming method. Examples of the film forming method include a calendar film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T-die extrusion method, a co-extrusion method, and a dry lamination method.

  Next, after a pressure-sensitive adhesive composition solution is applied onto the substrate 1 to form a coating film, the coating film is dried under predetermined conditions (heat-crosslinked as necessary), and the pressure-sensitive adhesive layer 2 is formed. Form. It does not specifically limit as a coating method, For example, roll coating, screen coating, gravure coating, etc. are mentioned. As drying conditions, for example, the drying temperature is 80 to 150 ° C. and the drying time is 0.5 to 5 minutes. Moreover, after apply | coating an adhesive composition on a separator and forming a coating film, the coating film may be dried on the said drying conditions, and the adhesive layer 2 may be formed. Then, the adhesive layer 2 is bonded together with the separator on the base material 1. Thereby, the dicing film 11 is produced. At this time, the surface of the dicing film bonded to the die bond film may be irradiated with ultraviolet rays in advance.

The die bond films 3 and 3 ′ are produced, for example, as follows.
First, an adhesive composition solution which is a material for forming the die bond films 3 and 3 ′ is prepared. As described above, the adhesive composition solution contains the adhesive composition, filler, and other various additives.

  Next, the adhesive composition solution is applied onto the base separator so as to have a predetermined thickness to form a coating film, and then the coating film is dried under predetermined conditions to form an adhesive layer. It does not specifically limit as a coating method, For example, roll coating, screen coating, gravure coating, etc. are mentioned. As drying conditions, for example, the drying temperature is 70 to 160 ° C. and the drying time is 1 to 5 minutes. Moreover, after apply | coating an adhesive composition solution on a separator and forming a coating film, you may dry an application film on the said drying conditions, and may form an adhesive bond layer. Then, an adhesive bond layer is bonded together with a separator on a base material separator.

  Subsequently, the separator is peeled off from each of the dicing film 11 and the adhesive layer, and the adhesive layer and the pressure-sensitive adhesive layer are bonded to each other so as to be a bonding surface. Bonding can be performed by, for example, pressure bonding. At this time, the lamination temperature is not particularly limited, and is preferably 30 to 50 ° C., for example, and more preferably 35 to 45 ° C. Moreover, a linear pressure is not specifically limited, For example, 0.1-20 kgf / cm is preferable and 1-10 kgf / cm is more preferable. Next, the base material separator on the adhesive layer is peeled off, and the dicing die-bonding film according to the present embodiment is obtained.

  When manufacturing a dicing die-bonding film using a long substrate, a roll-to-roll method can be suitably employed. A long base material wound in a roll shape is fed out, and a pressure-sensitive adhesive layer is formed on the transported base material according to a conventional method to obtain a dicing film. Usually, after covering an adhesive layer with a separator, it winds up in a roll shape again. Next, the separator is peeled off as the dicing film is fed from the roll. Separately, a die bond film formed on the separator is prepared, and the die bond film is bonded onto the adhesive layer of the dicing film while synchronizing the dicing film and the die bond film being conveyed. Thereby, the long dicing die-bonding film by which the die-bonding film was provided in the predetermined space | interval on the long dicing film provided with a long base material and an adhesive layer is obtained. A long dicing die-bonding film can be further wound into a roll to form a dicing die-bonding film wound body.

  When the roll-to-roll method is used, anisotropy occurs in the substrate when a strong tension is applied to the substrate during transportation, and the anisotropy of the tensile properties of the dicing film or dicing die bond film May be caused. From the viewpoint of reducing the anisotropy of the substrate, the tension during conveyance is preferably 0.01 N / mm or more and 1 N / mm or less, and more preferably 0.05 N / mm or more and 0.5 N / mm or less.

<Method for Manufacturing Semiconductor Device>
Next, a method for manufacturing a semiconductor device using the dicing die bond film 12 will be described with reference to FIGS. 3 to 6 are schematic cross-sectional views for explaining one method of manufacturing the semiconductor device according to this embodiment. First, the modified region is formed on the division line 4L by irradiating the division line 4L of the semiconductor wafer 4 with laser light. This method is a method of aligning a condensing point inside a semiconductor wafer, irradiating a laser beam along a grid-like division planned line, and forming a modified region inside the semiconductor wafer by ablation by multiphoton absorption. . What is necessary is just to adjust suitably within the range of the following conditions as laser beam irradiation conditions.

(Laser irradiation conditions)
(A) Laser light
Laser light source Semiconductor laser pumped Nd: YAG laser
Wavelength 1064nm
Laser light spot cross-sectional area 3.14 × 10 ⁻⁸ cm ²
Oscillation form Q switch pulse
Repeat frequency 100 kHz or less
Pulse width 1μs or less
Output 1mJ or less
Laser light quality TEM00
Polarization characteristics Linearly polarized light (B) Condensing lens
Magnification 100 times or less
NA 0.55
Transmittance with respect to laser beam wavelength: 100% or less (C) Moving speed of the table on which the semiconductor substrate is placed 280 mm / sec or less

  In addition, since the method of irradiating a laser beam to form a modified region on the planned division line 4L is described in detail in Japanese Patent No. 3408805 and Japanese Patent Application Laid-Open No. 2003-338567, details here. Detailed explanation will be omitted.

  Next, as shown in FIG. 4, the semiconductor wafer 4 after the modified region is formed is pressure-bonded onto the die bond film 3 ′, and this is bonded and held (fixing step). This step is performed while pressing with a pressing means such as a pressure roll. The attaching temperature at the time of mounting is not particularly limited, but is preferably in the range of 40 to 80 ° C. This is because warping of the semiconductor wafer 4 can be effectively prevented and the influence of expansion and contraction of the dicing die-bonding film can be reduced.

  Next, by applying a tensile stress to the dicing die-bonding film 12, the semiconductor wafer 4 and the die-bonding film 3 'are broken at the planned dividing line 4L to form the semiconductor chip 5 (chip forming step). In this step, for example, a commercially available wafer expansion device can be used. Specifically, as shown in FIG. 5A, a dicing ring 31 is attached to the periphery of the pressure-sensitive adhesive layer 2 of the dicing die-bonding film 12 to which the semiconductor wafer 4 is bonded, and then the wafer expansion device 32 is attached. Fix it. Next, as shown in FIG. 5 (b), the push-up portion 33 is raised, and the dicing die-bonding film 12 is tensioned and expanded.

  This chip forming step is preferably performed under conditions of −20 ° C. to 15 ° C., more preferably performed under conditions of −20 ° C. to 5 ° C., and conditions of −15 ° C. to 0 ° C. More preferably it is carried out in By executing the chip forming step under a low temperature condition as described above, the die bond film 3 'can be efficiently broken, and as a result, the manufacturing efficiency can be improved.

  Further, in the chip forming step, the expanding speed (speed at which the push-up part rises) is preferably 100 to 400 mm / second, more preferably 100 to 350 mm / second, and 100 to 300 mm / second. Further preferred. By setting the expanding speed to the above lower limit or more, the semiconductor wafer 4 and the die bond film 3 'can be easily broken at substantially the same time. Moreover, it can prevent that the dicing film 11 fractures | ruptures by making an expanding speed below the said upper limit.

  In the chip formation step, the amount of expand is preferably 6 to 12%. The amount of expansion may be adjusted as appropriate according to the chip size to be formed within the numerical range. In addition, in this embodiment, the amount of expand is the value (%) of the surface area increased by the expansion, with the surface area of the dicing film before expansion being 100%. By making the expand amount 6% or more, the semiconductor wafer 4 and the die bond film 3 can be easily broken. Moreover, it can prevent that the dicing film 11 fractures | ruptures by making expand amount into 12% or less.

  In this way, by applying a tensile stress to the dicing die bond film 12, the die bond film 3 is caused to crack in the thickness direction of the semiconductor wafer 4 starting from the modified region of the semiconductor wafer 4 and is in close contact with the semiconductor wafer 4. 'Can be broken, and the semiconductor chip 5 with the die bond film 3' can be obtained.

  Next, in order to peel off the semiconductor chip 5 adhered and fixed to the dicing die bond film 12, the semiconductor chip 5 is picked up (pickup process). The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, a method of pushing up the individual semiconductor chips 5 from the dicing die bond film 12 side with a needle and picking up the pushed-up semiconductor chips 5 with a pickup device may be mentioned.

  Here, since the pressure-sensitive adhesive layer 2 is an ultraviolet curable type, the pickup is performed after the pressure-sensitive adhesive layer 2 is irradiated with ultraviolet rays. Thereby, the adhesive force with respect to the die-bonding film 3 'of the adhesive layer 2 falls, and peeling of the semiconductor chip 5 becomes easy. As a result, the pickup can be performed without damaging the semiconductor chip 5. Conditions such as irradiation intensity and irradiation time at the time of ultraviolet irradiation are not particularly limited, and may be set as necessary. In addition, when the dicing die-bonding film in which the die-bonding film is bonded to the ultraviolet-cured dicing film is used, the ultraviolet irradiation here is unnecessary.

  Next, as shown in FIG. 6, the picked-up semiconductor chip 5 is die-bonded to the adherend 6 via the die-bonding film 3 '(temporary fixing step). Examples of the adherend 6 include a lead frame, a TAB film, a substrate, and a separately manufactured semiconductor chip. The adherend 6 may be, for example, a deformable adherend that can be easily deformed or a non-deformable adherend (such as a semiconductor wafer) that is difficult to deform.

  A conventionally well-known thing can be used as said board | substrate. As the lead frame, a metal lead frame such as a Cu lead frame or a 42 Alloy lead frame, or an organic substrate made of glass epoxy, BT (bismaleimide-triazine), polyimide, or the like can be used. However, the present invention is not limited to this, and includes a circuit board that can be used by bonding and fixing a semiconductor element and electrically connecting the semiconductor element.

  The shear adhesive strength at 25 ° C. at the time of temporarily fixing the die bond film 3 ′ is preferably 0.2 MPa or more, more preferably 0.2 to 10 MPa with respect to the adherend 6. When the shear bond strength of the die bond film 3 is at least 0.2 MPa or more, the die bond film 3 and the semiconductor chip 5 or the adherend 6 are bonded by ultrasonic vibration or heating in the wire bonding process. Less shear deformation occurs on the adhesive surface. That is, the semiconductor element is less likely to move due to ultrasonic vibration during wire bonding, thereby preventing the success rate of wire bonding from decreasing. Moreover, it is preferable that the shear adhesive force at 175 degreeC at the time of temporary adhering of die-bonding film 3 'is 0.01 Mpa or more with respect to the to-be-adhered body 6, More preferably, it is 0.01-5 Mpa.

  Next, wire bonding is performed in which the tip of the terminal portion (inner lead) of the adherend 6 and an electrode pad (not shown) on the semiconductor chip 5 are electrically connected by the bonding wire 7 (wire bonding step). As the bonding wire 7, for example, a gold wire, an aluminum wire, a copper wire or the like is used. The temperature at the time of wire bonding is 80 to 250 ° C, preferably 80 to 220 ° C. The heating time is several seconds to several minutes. The connection is performed by a combination of vibration energy by ultrasonic waves and crimping energy by applying pressure while being heated so as to be within the temperature range. This step can be performed without performing thermosetting of the die bond film 3a. Further, the semiconductor chip 5 and the adherend 6 are not fixed by the die bond film 3a in the course of this step.

  Next, the semiconductor chip 5 is sealed with the sealing resin 8 (sealing step). This step is performed to protect the semiconductor chip 5 and the bonding wire 7 mounted on the adherend 6. This step is performed by molding a sealing resin with a mold. As the sealing resin 8, for example, an epoxy resin is used. Although the heating temperature at the time of resin sealing is normally performed at 175 degreeC for 60 to 90 second, this invention is not limited to this, For example, it can cure at 165 to 185 degreeC for several minutes. Thereby, the sealing resin is cured, and the semiconductor chip 5 and the adherend 6 are fixed through the die bond film 3. That is, in the present invention, even when the post-curing step described later is not performed, the die bonding film 3 can be fixed in this step, and the number of manufacturing steps can be reduced and the semiconductor device manufacturing period can be reduced. It can contribute to shortening.

  In the post-curing step, the sealing resin 8 that is insufficiently cured in the sealing step is completely cured. Even if the die bond film 3a is not completely thermoset in the sealing step, the die bond film 3a can be completely thermoset together with the sealing resin 8 in this step. Although the heating temperature in this process changes with kinds of sealing resin, it exists in the range of 165-185 degreeC, for example, and heating time is about 0.5 to 8 hours.

  In the embodiment described above, the case where the wire bonding process is performed without temporarily curing the die bond film 3 ′ after temporarily fixing the semiconductor chip 5 with the die bond film 3 ′ to the adherend 6 has been described. However, in the present invention, after the semiconductor chip 5 with the die bond film 3 ′ is temporarily fixed to the adherend 6, the die bond film 3 ′ is thermally cured, and then a normal die bond process is performed in which a wire bonding process is performed. It is good as well. In this case, it is preferable that the die-bonding film 3 ′ after thermosetting has a shear adhesive force of 0.01 MPa or more at 175 ° C., and more preferably 0.01 to 5 MPa. By setting the shear adhesive strength at 175 ° C. after thermosetting to 0.01 MPa or more, the die bond film 3 ′ and the semiconductor chip 5 or the adherend 6 are caused by ultrasonic vibration or heating in the wire bonding step. This is because it is possible to prevent shear deformation from occurring on the adhesive surface.

  In addition, the dicing die-bonding film of this invention can be used suitably also when laminating | stacking a several semiconductor chip and carrying out three-dimensional mounting. At this time, the die bond film and the spacer may be laminated between the semiconductor chips, or only the die bond film may be laminated between the semiconductor chips without laminating the spacers. Is possible.

  Hereinafter, preferred embodiments of the present invention will be described in detail by way of example. However, the materials, blending amounts, and the like described in this example are not intended to limit the gist of the present invention only to those unless otherwise limited.

<Examples 1-3 and Comparative Examples 1-2>
<Manufacture of dicing film>
(Production Example 1)
In a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer and a stirring device, 76 parts of 2-ethylhexyl acrylate (2EHA), 24 parts of 2-hydroxyethyl acrylate (HEA), and benzoyl peroxide 0.2 Part and 60 parts of toluene were added and polymerized in a nitrogen stream at 61 ° C. for 6 hours to obtain an acrylic polymer A. The molar ratio of 2EHA to HEA was 100 mol to 20 mol.

  To this acrylic polymer A, 10 parts of 2-methacryloyloxyethyl isocyanate (hereinafter referred to as “MOI”) (80 mol% with respect to HEA) was added, and an addition reaction treatment was performed at 50 ° C. for 48 hours in an air stream. An acrylic polymer A ′ was obtained.

  Next, with respect to 100 parts of acrylic polymer A ′, 6 parts of an isocyanate crosslinking agent (trade name “Coronate L”, manufactured by Nippon Polyurethane Co., Ltd.) and a photopolymerization initiator (trade name “Irgacure 651”, Ciba 4 parts) (manufactured by Specialty Chemicals) was added to prepare an adhesive solution.

  The pressure-sensitive adhesive solution prepared above was applied on the surface of the PET release liner that had been subjected to the silicone treatment, and heat-crosslinked at 120 ° C. for 2 minutes to form a pressure-sensitive adhesive layer precursor having a thickness of 30 μm. Subsequently, a base film with a thickness of 80 μm having a two-layer structure of a polypropylene layer and a polyethylene layer was prepared, and the base film was bonded to the surface of the pressure-sensitive adhesive precursor using the polypropylene layer as a bonding surface. Thereafter, it was stored at 50 ° C. for 24 hours. The pressure-sensitive adhesive layer was formed by irradiating only the portion (diameter 220 mm) corresponding to the semiconductor wafer attachment portion (diameter 200 mm) of the pressure-sensitive adhesive layer precursor. Thereby, the dicing film A which concerns on this manufacture example was produced. The irradiation conditions are as follows.

<Ultraviolet irradiation conditions>
Ultraviolet (UV) irradiation device: high-pressure mercury lamp UV irradiation integrated light quantity: 500 mJ / cm ²
Output: 120W
Irradiation intensity: 200 mW / cm ²

(Production Example 2)
Other than preparing a base film with a thickness of 100 μm having a two-layer structure of a polypropylene layer and a polyethylene layer as the base film, and bonding the base film with the polypropylene layer as a bonding surface on the pressure-sensitive adhesive precursor surface Produced a dicing film B in the same manner as in Production Example 1.

(Production Example 3)
As a base film, a 40 μm-thick base film having a one-layer structure in which polypropylene and polyethylene are blended is prepared, and the same as in Production Example 1 except that this and the adhesive precursor surface are bonded together. Thus, a dicing film C was produced.

(Production Example 4)
A base film having a thickness of 90 μm having a three-layer structure of a blend layer of polypropylene and polyethylene, an ethylene-vinyl acetate copolymer layer, and a blend layer of polypropylene and polyethylene is prepared as a base film, and the pressure-sensitive adhesive precursor surface A dicing film D was prepared in the same manner as in Production Example 1 except that any of the blend layers was used as a bonding surface and the base film was bonded.

<Manufacture of die bond film>
(Production Example 5)
The following (a) to (d) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Acrylic acid ester polymer mainly composed of ethyl acrylate-methyl methacrylate (manufactured by Nagase ChemteX Corporation, SG-P3, glass transition temperature: 15 ° C.)
48 parts by weight (a) epoxy resin (manufactured by Tohto Kasei Co., Ltd., KI-3000, epoxy equivalent 105, softening point 70 ° C.)
6 parts by weight (b) phenol resin (Maywa Kasei Co., Ltd., MEH-7800M, hydroxyl equivalent 175)
6 parts by weight (d) filler (manufactured by Admatechs, SO-E2, fused spherical silica, average particle size 0.5 μm) 40 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thereby, a die bond film A having a thickness of 10 μm was produced.

(Production Example 6)
The following (a) to (e) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Acrylic acid ester polymer mainly composed of ethyl acrylate-methyl methacrylate (manufactured by Nagase ChemteX Corporation, SG-P3, glass transition temperature: 15 ° C.)
32 parts by weight (a) epoxy resin (manufactured by Tohto Kasei Co., Ltd., KI-3000, epoxy equivalent 105, softening point 70 ° C.)
4 parts by weight (b) phenol resin (Maywa Kasei Co., Ltd., MEH-7800M, hydroxyl equivalent 175)
4 parts by weight (d) filler (manufactured by Admatechs, SO-E2, fused spherical silica, average particle size 0.5 μm) 60 parts by weight (e) silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403) 0 .05 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thus, a die bond film B having a thickness of 10 μm was produced.

<Manufacture of dicing die bond film>
In the combinations shown in Table 1, the die bond film and the dicing film were bonded at a lamination temperature of 40 ° C. and a linear pressure of 2 kgf / cm, and the dicing die bond films A to E according to Examples and Comparative Examples were used.

(Measurement of tensile modulus at 0 ° C)
About dicing film AD, the tensile elasticity modulus in MD direction and TD direction in 0 degreeC was measured, respectively. Specifically, the dicing film was cut into a 10 mm width × 50 mm length with a cutter knife and measured using an autograph (manufactured by Shimadzu Corporation) at a distance between chucks of 10 mm and a tensile speed of 50 mm / min. From the obtained SS curve, the tensile modulus was determined using the value at the time of 3% elongation. The total thickness of the base material and the pressure-sensitive adhesive layer was used as the sample thickness used for the calculation. The results are shown in Table 1.

(Confirm breakability)
Using ML300-Integration, manufactured by Tokyo Seimitsu Co., Ltd. as the laser processing device, the condensing point is aligned inside the semiconductor wafer, and laser light is emitted from the surface side of the semiconductor wafer along the grid-like (10 mm × 10 mm) division line. Irradiated to form a modified region inside the semiconductor wafer. As the semiconductor wafer, a silicon wafer (thickness: 75 μm, outer diameter: 12 inches) was used. The laser light irradiation conditions were as follows.

(A) Laser light
Laser light source Semiconductor laser pumped Nd: YAG laser
Wavelength 1064nm
Laser light spot cross-sectional area 3.14 × 10 ⁻⁸ cm ²
Oscillation form Q switch pulse
Repetition frequency 100kHz
Pulse width 30ns
Output 20μJ / pulse
Laser light quality TEM00 40
Polarization characteristics Linearly polarized (B) condensing lens
50 times magnification
NA 0.55
60% transmittance for laser wavelength
(C) Moving speed of the table on which the semiconductor substrate is placed 100 mm / second

  A rupture test was performed on each of the dicing die-bonding films A to E after bonding a semiconductor wafer that had been pretreated with laser light. The break test was performed under the condition of an expansion temperature of 0 ° C. The expanding speed was 400 mm / second, and the expanding amount was 6%. As a result of the expansion, the number of chips in which the chip and the die-bonding film were satisfactorily broken in the planned division line was counted for the central 100 chips of the semiconductor wafer, and the ratio was obtained. The results are shown in Table 1.

(Peeling force measurement)
A tape (manufactured by Nitto Denko Corporation, trade name: BT-315) was attached to the dicing die bond film on the die bond film side and reinforced at room temperature. It cut | disconnected to 100 mm width x 120 mm length with the cutter knife. Thereafter, the pressure-sensitive adhesive layer of the dicing film and the die-bonding film are chucked, and at 0 ° C. and 23 ° C., using a tensile tester (manufactured by Shimadzu Corporation, trade name: AGS-J), the peeling speed is 300 mm. / Min, the force (maximum load, unit: N / 100 mm) when the pressure-sensitive adhesive layer and the die bond film were peeled off in the T-type peel test was read. The results are shown in Table 1.

  In the dicing die-bonding film of the example, breakability by laser dicing was good. Further, the peeling force at 0 ° C. was high and the holding property of the semiconductor wafer was excellent, while the peeling force at 23 ° C. was low and the pickup property was excellent. On the other hand, the dicing die-bonding films of Comparative Examples 1 and 2 had a large variation in physical properties in the TD direction and the MD direction, resulting in poor breakability due to laser dicing.

DESCRIPTION OF SYMBOLS 1 Base material 2 Adhesive layer 3, 3 'Die bond film (thermosetting type die bond film)
4 Semiconductor wafer 5 Semiconductor chip 6 Substrate 7 Bonding wire 8 Sealing resin 10, 12 Dicing die-bonding film 11 Dicing film

Claims (7)

A dicing film comprising a substrate and an adhesive layer provided on the substrate;
A dicing die-bonding film comprising a thermosetting die-bonding film provided on the adhesive layer of the dicing film,
The tensile elastic modulus in the MD direction obtained from the stress-strain curve obtained when a tensile stress is applied at 0 ° C. in each of the MD direction and the TD direction of the dicing film is _E′MD1, and the tensile elastic modulus in the TD direction is When E ′ _TD1 is set, _E′MD1 / _E′TD1 is 0.75 or more and 1.25 or less,
The die bond film contains an epoxy resin, a phenol resin, and an acrylic resin,
Wherein the total weight of the epoxy resin and the phenolic resin and X, when the weight of the acrylic resin was Y, Ri X / (X + Y) is 0.3 or more 0.9 than der,
A dicing die-bonding film in which an absolute value of a difference between the tensile elastic modulus E ′ _MD1 and the tensile elastic modulus E ′ _TD1 of the dicing film is 1 MPa or more and 50 MPa or less . The tension dicing die-bonding film according to claim 1, wherein at least one of which is less 100MPa or more 10MPa of elastic modulus E _'MD1 and the tensile modulus E' _TD1 of the dicing film. The peel strength at 0 ℃ between the adhesive layer and the thermosetting die-bonding film, the higher claim than peel strength at 23 ° C. between the adhesive layer and the thermosetting die-bonding film 1 or 2 The dicing die-bonding film described in 1. The dicing die-bonding film according to any one of claims 1 to 3 , wherein a peeling force at 0 ° C between the pressure-sensitive adhesive layer and the thermosetting die-bonding film is 0.15 N / 100 mm or more and 5 N / 100 mm or less. . The dicing die-bonding film according to claim 3 or 4 , wherein a peeling force at 23 ° C between the pressure-sensitive adhesive layer and the thermosetting die-bonding film is 0.05 N / 100 mm or more and 2.5 N / 100 mm or less. After forming the modified region by irradiating a laser beam to the semiconductor wafer, any claim 1-5 for use of the semiconductor wafer to a method of manufacturing a semiconductor device to obtain a semiconductor device by breaking at the modified region The dicing die-bonding film according to claim 1. Irradiating a laser beam to the division line of the semiconductor wafer to form a modified region along the division line; and
The step of bonding the semiconductor wafer after the modified region formation to the dicing die-bonding film according to any one of claims 1 to 6 ,
By applying tensile stress to the dicing die-bonding film under the condition of −20 ° C. to 15 ° C., the semiconductor wafer and the die-bonding film of the dicing die-bonding film are ruptured along the scheduled dividing line. Forming a step;
Picking up the semiconductor element together with the die bond film;
And a step of die-bonding the picked-up semiconductor element to an adherend through the die-bonding film.