TWI850371B - Die cutting film - Google Patents

Abstract

The present invention provides a wafer-cutting adhesive film in which the adhesive layer is not easily broken when the adhesive layer is expanded for cutting. The present invention is a wafer-cutting adhesive film, which comprises: a wafer-cutting tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer which is releasably and closely attached to the adhesive layer in the wafer-cutting tape; and the adhesive layer side surface of the substrate is surface-treated, and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15℃)/(Peeling force at 25℃)≧1 (1)

Description

Die cutting film

The present invention relates to a wafer bonding film. More specifically, the present invention relates to a wafer bonding film that can be used in a semiconductor device manufacturing process.

In the process of manufacturing semiconductor devices, in the process of obtaining a semiconductor chip with an adhesive film of the same size as the chip for die bonding, that is, a semiconductor chip with an adhesive layer for die bonding, a die bonding film is used. The die bonding film has a size corresponding to the semiconductor wafer as a processing object, for example, a die bonding tape including a substrate and an adhesive layer, and a die bonding film (adhesive layer) that is releasably closely attached to the side of the adhesive layer.

In recent years, semiconductor wafers have been thinning continuously. However, when the thinned semiconductor wafers are cut, the previous blade cutting method has the problem that the wafers are easily damaged and damaged. Therefore, there is a known method through the following steps, which is used to use a cutting die-bonding film to expand the cutting tape in the cutting die-bonding film to cut the die-bonding film and the semiconductor wafer.

In the method, first, a semiconductor wafer is bonded to a die-bonding film of a die-bonding film, and then the semiconductor wafer is cut together with the die-bonding film, and processed into a plurality of semiconductor chips.

Next, in order to cut the die-bonding film on the die-bonding tape, an expansion device is used to stretch the die-bonding tape of the die-bonding film in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer. In the expansion step, the semiconductor wafer on the die-bonding film is also cut at a position corresponding to the cut position in the die-bonding film, and the semiconductor wafer is singulated into a plurality of semiconductor chips on the die-bonding film or the die-bonding tape.

Next, for the multiple semiconductor chips with adhesive films on the dicing tape that have been cut, a further expansion step is performed to increase the separation distance. Next, for example, after a cleaning step, each semiconductor chip and the adhesive film of the same size as the chip in close contact with it are lifted up from the bottom side of the dicing tape by the pin member of the pickup mechanism, and picked up from the dicing tape. In this way, a semiconductor chip with an adhesive film, i.e., an adhesive layer, is obtained. The semiconductor chip with the adhesive layer is fixed to a mounting substrate or other attached body by adhesive bonding through its adhesive layer.

The related technology of the wafer bonding film used as described above is described in, for example, the following patent documents 1-3. [Prior art document] [Patent document]

[Patent Document 1] Japanese Patent Publication No. 2007-2173 [Patent Document 2] Japanese Patent Publication No. 2010-177401 [Patent Document 3] Japanese Patent Publication No. 2016-115804

[The problem the invention is trying to solve]

However, there is a case where the adhesive layer in the dicing tape is broken when the dicing tape of the dicing adhesive film is stretched in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer using an expansion device to cut the adhesive layer. There is a case where if the adhesive layer is broken when the adhesive layer is cut by expansion, the stress generated when the dicing tape is stretched is not effectively transferred to the adhesive layer, and the adhesive layer cannot be properly cut.

The present invention is made in view of the above-mentioned problem, and its purpose is to provide a wafer-cutting adhesive film in which the adhesive layer is not easily broken when the adhesive layer is expanded. [Technical means to solve the problem]

The inventors of the present invention have conducted in-depth research to achieve the above-mentioned purpose, and as a result, have found that if the following wafer bonding film is used, the adhesive layer is not easily broken when the expansion for cutting the adhesive layer is used, and the wafer bonding film comprises: a wafer bonding tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer that is peelably attached to the adhesive layer in the wafer bonding tape; and the surface of the substrate on the adhesive layer side is subjected to surface treatment, and the peeling force between the substrate and the adhesive layer at -15°C is greater than the peeling force at 25°C. The present invention has been completed based on these findings.

That is, the present invention is a wafer-cutting adhesive film, which comprises: a wafer-cutting tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer which is releasably closely attached to the adhesive layer in the wafer-cutting tape; and the surface of the substrate on the adhesive layer side is surface-treated, and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15°C)/(Peeling force at 25°C)≧1 (1)

The wafer-cutting adhesive film of the present invention comprises a wafer-cutting tape and an adhesive layer. The wafer-cutting tape has a laminated structure including a substrate and an adhesive layer. The adhesive layer is releasably and closely attached to the adhesive layer in the wafer-cutting tape. The wafer-cutting adhesive film of such a structure can be used to obtain a semiconductor chip with an adhesive layer attached in the manufacturing process of a semiconductor device.

In the manufacturing process of semiconductor devices, as described above, in order to obtain a semiconductor chip with an adhesive layer attached, there is a case where an expansion step using a wafer-cutting adhesive film, that is, an expansion step for cutting, is implemented. In the expansion step, it is necessary to make the cutting force act appropriately on the adhesive layer on the wafer-cutting tape in the wafer-cutting adhesive film. The side surface of the adhesive layer of the substrate of the wafer-cutting tape in the wafer-cutting adhesive film of the present invention is surface-treated, and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the above formula (1). According to the wafer bonding film of the present invention having such a structure, when the adhesive layer is expanded for cutting (especially when expanded at low temperature), the adhesive layer is not easily broken. In addition, by satisfying the above formula (1), there is a tendency to obtain such an effect independently of the type of substrate.

In the die-bonding film of the present invention, the peeling force between the substrate and the adhesive layer at -15°C is preferably more than 6.5 N/10 mm. According to the die-bonding film of the present invention having such a structure, the adhesive layer is firmly held on the substrate at low temperatures, and the adhesive layer is less likely to break during expansion for cutting the adhesive layer (especially expansion at low temperatures).

Furthermore, in the wafer-cutting adhesive film of the present invention, the adhesive layer is preferably an acrylic adhesive layer. According to the wafer-cutting adhesive film of the present invention having such a structure, it is easy to design an adhesive layer that satisfies the above formula (1). [Effect of the invention]

According to the wafer-cutting adhesive film of the present invention, the adhesive layer is not easily broken when the adhesive layer is expanded to cut during the process of manufacturing semiconductor devices. Therefore, the stress generated by stretching the wafer-cutting adhesive tape when cutting the adhesive layer is effectively transmitted to the adhesive layer, so that the adhesive layer can be cut more appropriately.

[Cut wafer adhesive film] The cut wafer adhesive film of the present invention comprises: a cut wafer adhesive tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer which is releasably and closely attached to the adhesive layer in the cut wafer adhesive tape. Hereinafter, one embodiment of the cut wafer adhesive film of the present invention will be described.

In addition, the present specification also describes the invention of a die-cutting adhesive film, which comprises: a die-cutting adhesive tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer which is releasably and closely attached to the adhesive layer in the die-cutting adhesive tape; and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). The preferred structure of the die-cutting adhesive film is the same as that described for the die-cutting adhesive film of the present invention.

In addition, the present specification also describes the invention of a dicing tape having a laminated structure including a substrate and an adhesive layer, wherein the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). The preferred structure of the dicing tape is the same as that described for the dicing tape in the dicing adhesive film of the present invention.

Fig. 1 is a cross-sectional schematic diagram showing an embodiment of the wafer bonding film of the present invention. As shown in Fig. 1, the wafer bonding film 1 has a wafer bonding tape 10 and an adhesive layer 20 laminated on an adhesive layer 12 in the wafer bonding tape 10, and can be used in an expansion step in the process of obtaining a semiconductor chip with an adhesive layer attached in the manufacture of a semiconductor device.

The die-cutting die-bonding film 1 has a disc shape with a size corresponding to a semiconductor wafer that is a processing object in the manufacturing process of a semiconductor device. The diameter of the die-cutting die-bonding film 1 is, for example, in the range of 345 to 380 mm (corresponding to a 12-inch wafer), 245 to 280 mm (corresponding to an 8-inch wafer), 195 to 230 mm (corresponding to a 6-inch wafer), or 495 to 530 mm (corresponding to an 18-inch wafer).

The die-cutting adhesive tape 10 in the die-cutting adhesive film 1 has a laminated structure including a substrate 11 and an adhesive layer 12. The relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate 11 and the adhesive layer 12 in the die-cutting adhesive film 1, i.e., between the surface 11a of the substrate 11 in close contact with the adhesive layer 12 and the surface 12a of the adhesive layer 12 in close contact with the substrate 11, satisfies the following formula (1).

In the wafer-cutting adhesive film of the present invention, the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). Since the peeling force between the substrate and the adhesive layer satisfies the following formula (1), the adhesive layer is not easily broken during expansion for cutting the adhesive layer (especially expansion at low temperature). In addition, there is a tendency that this effect is obtained by satisfying the above formula (1) without depending on the type of substrate. (Peeling force at -15°C)/(Peeling force at 25°C)≧1 (1)

The peeling force between the substrate and the adhesive layer at -15°C is preferably greater than 6.5 N/10 mm, more preferably greater than 7.5 N/10 mm, and further preferably greater than 8.5 N/10 mm. If the peeling force at -15°C is greater than 6.5 N/10 mm, the adhesive layer is firmly held on the substrate at low temperatures, and the adhesive layer is less likely to break during expansion (especially expansion at low temperatures) for cutting the adhesive layer. Furthermore, the peeling force at -15°C may be, for example, less than 50 N/10 mm, or less than 25 N/10 mm.

The peeling force between the substrate and the adhesive layer at 25°C is preferably 0.5 N/10 mm or more, more preferably 1.0 N/10 mm or more, and further preferably 1.5 N/10 mm or more. If the peeling force at 25°C is 0.5 N/10 mm or more, the adhesion between the substrate and the adhesive layer during expansion for increasing the separation distance of the semiconductor chip to which the adhesive layer is attached is higher, and the adhesive layer is not easily broken during the expansion. Furthermore, the peeling force at 25°C may be, for example, 50 N/10 mm or less, or 15 N/10 mm or less.

In this specification, the peeling force between the substrate and the adhesive layer at -15°C and the peeling force at 25°C are based on the T-type peeling strength measured according to JIS K 6854-3. Specifically, the peeling strength is measured by the following measurement method.

<Method for measuring the peeling force between substrate and adhesive layer> A laminate obtained by laminating a strong adhesive tape on the adhesive layer surface of a wafer tape or the adhesive layer surface of a wafer adhesive film is used as a test sample. The substrate and adhesive layer of the test sample are peeled off by a T-type peel test under the conditions of a specified temperature and a tensile speed of 300 mm/min to measure the peeling force.

The surface 12a of the adhesive layer 12 of the substrate 11 is subjected to surface treatment. Examples of the surface treatment include physical treatments such as corona discharge treatment, plasma treatment, frosting treatment, ozone exposure treatment, flame exposure treatment, high-voltage electric shock exposure treatment, and ionizing radiation treatment; chemical treatments such as chromic acid treatment; and easy-to-adhesion treatment using a coating agent (primer). By performing the surface treatment, the peeling force between the substrate and the adhesive layer at -15°C is significantly increased compared to the case where the surface treatment is not performed. This phenomenon is speculated as follows. The reason is that when the surface treatment is not performed, interfacial peeling occurs during peeling. Compared with the -15°C environment, the adhesive force of the adhesive layer is more easily expressed in the 25°C environment, so the peeling force tends to be greater at 25°C. On the other hand, when the surface treatment is applied, a chemical bond (covalent bond, etc.) is formed between the substrate or surface treatment layer and the adhesive layer. In a 25°C environment, the chemical bond is easy to break, the energy consumed by the coagulation destruction is small, and the improvement of the peeling force is relatively small. In contrast, in a -15°C environment, the chemical bond is not easy to break, the energy consumed by the coagulation destruction is large, and the improvement of the peeling force becomes relatively large. As the above-mentioned surface treatment, the corona treatment is preferred.

Furthermore, when an easy-to-attach treatment using a coating agent (primer) is performed as the surface treatment of the substrate, the peeling force that becomes the object of measurement in the above-mentioned peeling force measurement may be the peeling force caused by the cohesion destruction of the layer (coating layer) formed by the coating agent (coating layer) (cohesion peeling), or may be the peeling force in the peeling of the interface between the coating layer and the substrate or between the coating layer and the adhesive layer (interface peeling).

The above surface treatment is preferably performed on the entire surface of the adhesive layer side of the substrate. In addition, in order to impart antistatic properties, a conductive vapor-deposited layer containing metals, alloys, oxides thereof, etc. may be provided on the substrate surface.

In addition, in this specification, when a preferred upper limit value and a preferred lower limit value are respectively shown for a numerical range, it is regarded as describing all numerical ranges combining any one of all upper limits and any one of all lower limits cited as examples.

(Substrate) The substrate in the wafer tape is an element that functions as a support in the wafer tape or wafer adhesive film. As a substrate, for example, a plastic substrate (especially a plastic film) can be cited. The above-mentioned substrate can be a single layer or a laminate of the same or different substrates.

Examples of the resin constituting the plastic substrate include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolypropylene, polybutene, polymethylpentene, ethylene-vinyl acetate copolymer (EVA), ionic polymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate (random, alternating) copolymer , ethylene-butene copolymer, ethylene-hexene copolymer and other polyolefin resins; polyurethane; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate, and polybutylene terephthalate (PBT); polycarbonate; polyimide; polyetheretherketone; polyetherimide; polyamides such as aromatic polyamide and wholly aromatic polyamide; polyphenylene sulfide; fluororesin; polyvinyl chloride; polyvinylidene chloride; cellulose resin; polysilicone resin, etc. From the viewpoint of easily ensuring good thermal shrinkage in the substrate and maintaining the chip separation distance by utilizing the local thermal shrinkage of the dicing tape or the substrate in the following room temperature expansion step, the substrate preferably contains ethylene-vinyl acetate copolymer as a main component.

Furthermore, the main component of the substrate refers to the component that accounts for the largest mass ratio among the constituent components. The above-mentioned resin may be used alone or in combination. When the adhesive layer is a radiation-curing adhesive layer as described below, the substrate is preferably radiation-transmissive.

When the substrate is a plastic film, the plastic film may be non-oriented or may be oriented in at least one direction (uniaxial direction, biaxial direction, etc.). When oriented in at least one direction, the plastic film can be thermally shrunk in the at least one direction. If it has thermal shrinkage, the outer peripheral portion of the semiconductor wafer of the wafer-cutting tape can be thermally shrunk, thereby fixing the intervals between the semiconductor chips with the adhesive layer that have been singulated in an expanded state, so that the semiconductor chips can be easily picked up. In order to make the substrate and the wafer-cutting tape have isotropic thermal shrinkage, the substrate is preferably a biaxially oriented film. Furthermore, the plastic film oriented in at least one direction can be obtained by stretching an unstretched plastic film in the at least one direction (uniaxial stretching, biaxial stretching, etc.).

The heat shrinkage of the substrate and the wafer-cutting tape in the heat treatment test at a heating temperature of 100°C and a heating time of 60 seconds is preferably 1-30%, more preferably 2-25%, further preferably 3-20%, and particularly preferably 5-20%. The above heat shrinkage is preferably the heat shrinkage in at least one direction of the MD direction and the TD direction.

From the perspective of ensuring the strength for the substrate to function as a support in the dicing tape and the dicing adhesive film, the thickness of the substrate is preferably 40 μm or more, more preferably 50 μm or more, further preferably 55 μm or more, and particularly preferably 60 μm or more. Furthermore, from the perspective of achieving appropriate flexibility in the dicing tape and the dicing adhesive film, the thickness of the substrate is preferably 200 μm or less, more preferably 180 μm or less, and further preferably 150 μm or less.

(Adhesive layer) The adhesive layer of the wafer-cutting tape is preferably an adhesive layer containing an acrylic polymer as a base polymer (acrylic adhesive layer). The acrylic polymer is a polymer containing a structural unit derived from an acrylic monomer (a monomer component having a (meth)acryl group in the molecule) as a structural unit of the polymer.

The acrylic polymer is preferably a polymer containing the most structural units derived from (meth)acrylate in terms of mass ratio. In addition, only one type of acrylic polymer may be used, or two or more types may be used. In this specification, "(meth)acrylic acid" means "acrylic acid" and/or "methacrylic acid" (either or both of "acrylic acid" and "methacrylic acid"), and the same applies to the others.

Examples of the (meth)acrylate include alkyl-containing (meth)acrylates which may have an alkoxy group. Examples of the alkyl-containing (meth)acrylate include alkyl (meth)acrylates, cycloalkyl (meth)acrylates, and aryl (meth)acrylates.

Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, isoamyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, hexadecyl (meth)acrylate, octadecyl (meth)acrylate, and the like.

Examples of the cycloalkyl (meth)acrylate include cyclopentyl (meth)acrylate and cyclohexyl (meth)acrylate. Examples of the aryl (meth)acrylate include phenyl (meth)acrylate and benzyl (meth)acrylate.

Examples of the alkyl-containing (meth)acrylate having an alkoxy group include those obtained by replacing one or more hydrogen atoms in the alkyl group of the above-mentioned alkyl-containing (meth)acrylate with an alkoxy group, such as 2-methoxymethyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-methoxybutyl (meth)acrylate, and the like.

The above-mentioned alkyl group-containing (meth)acrylate which may have an alkoxy group may be used alone or in combination of two or more.

The above-mentioned alkyl-containing (meth)acrylate which may also have an alkoxy group preferably has a total carbon number in the ester portion (including the total carbon number in the alkoxy group when having an alkoxy group) of 6 to 10. In particular, the alkyl-containing (meth)acrylate has a total carbon number in the alkyl group of 6 to 10. In such a case, the glass transition temperature of the polymer in the adhesive layer tends to be higher, and the peeling force at low temperature tends to be higher, so that it is easy to design a dicing tape satisfying the above formula (1).

In order to properly express the basic characteristics such as adhesiveness obtained by the (meth)acrylate which may also have an alkoxy group in the adhesive layer, the ratio of the (meth)acrylate which may also have an alkoxy group in all monomer components used to form the acrylic polymer is preferably 20 mol% or more, more preferably 30 mol% or more, and further preferably 40 mol% or more.

Furthermore, in this specification, the above-mentioned monomer components do not include compounds having a radiation polymerizable group (e.g., compounds having the second functional group described below and a radiation polymerizable carbon-carbon double bond) at the stage of being incorporated into the polymer before irradiating the adhesive layer with radiation.

The acrylic polymer may also contain structural units derived from other monomer components that can be copolymerized with the alkyl-containing (meth)acrylate that may also have an alkoxy group in order to improve cohesive force, heat resistance, etc. Examples of the other monomer components include polar group-containing monomers such as carboxyl group-containing monomers, acid anhydride monomers, hydroxyl group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, and nitrogen atom-containing monomers.

Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid.

Examples of the acid anhydride monomer include maleic anhydride and itaconic anhydride. Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl (meth)acrylate.

Examples of the glycidyl group-containing monomer include glycidyl (meth)acrylate and methylglycidyl (meth)acrylate.

Examples of the sulfonic acid group-containing monomer include styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid.

Examples of the phosphoric acid group-containing monomer include 2-hydroxyethyl acrylylphosphate and the like.

Examples of the nitrogen atom-containing monomer include N-thiophene group-containing monomers such as (meth)acryloylthiophene, cyano group-containing monomers such as (meth)acrylonitrile, and amide group-containing monomers such as (meth)acrylamide.

As the above-mentioned other monomer components, hydroxyl-containing monomers and nitrogen-containing monomers (especially N-thiophene-containing monomers) are preferred, and 2-hydroxyethyl (meth)acrylate (2-hydroxyethyl (meth)acrylate) and (meth)acryloylthiophene are more preferred. That is, the above-mentioned acrylic polymer preferably contains a structural unit derived from 2-hydroxyethyl (meth)acrylate and/or a structural unit derived from (meth)acryloylthiophene.

The above-mentioned other monomer components may be used alone or in combination of two or more.

In order to properly express the basic characteristics such as adhesion obtained by the alkyl-containing (meth)acrylate which may also have an alkoxy group in the adhesive layer, the total ratio of the above-mentioned polar group-containing monomers in all monomer components used to form the acrylic polymer is preferably 60 mol% or less, and more preferably 50 mol% or less. In addition, from the perspective of increasing the glass transition temperature of the polymer in the adhesive layer, easily increasing the peeling force at low temperature, and facilitating the design of the wafer-cutting tape satisfying the above formula (1), the total ratio of the above-mentioned polar group-containing monomers is preferably 5 mol% or more, and more preferably 10 mol% or more.

In order to properly express the basic characteristics such as adhesiveness obtained by the alkyl-containing (meth)acrylate which may also have an alkoxy group in the adhesive layer, the ratio of the structural unit derived from the hydroxyl-containing monomer in all the monomer components used to form the acrylic polymer is preferably 5 mol% or more, more preferably 10 mol% or more. In addition, the above ratio is, for example, 80 mol% or less, and may also be 70 mol% or less, or 60 mol% or less.

When the nitrogen-containing monomer is used as a monomer component for forming an acrylic polymer, the ratio of structural units derived from the nitrogen-containing monomer in all monomer components for forming the acrylic polymer is preferably 3 mol% or more, more preferably 5 mol% or more. In addition, the above ratio is, for example, 50 mol% or less, and may also be 30 mol% or less, or 20 mol% or less.

The acrylic polymer may also contain structural units derived from a multifunctional monomer that can copolymerize with the monomer components that form the acrylic polymer in order to form a cross-linked structure in the polymer skeleton. Examples of the multifunctional monomer include monomers having a (meth)acryl group and other reactive functional groups in the molecule, such as 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, trihydroxymethylpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy (meth)acrylate (e.g., poly(meth)acrylate glycidyl), polyester (meth)acrylate, and urethane (meth)acrylate.

The above-mentioned multifunctional monomers may be used alone or in combination. In order to properly express the basic properties such as adhesion obtained by the alkyl-containing (meth)acrylate which may also have an alkoxy group in the adhesive layer, the ratio of the above-mentioned multifunctional monomers in all monomer components used to form the acrylic polymer is preferably 40 mol% or less, more preferably 30 mol% or less.

The acrylic polymer preferably has a structural unit derived from a monomer having a first functional group (e.g., the above-mentioned polar group-containing monomer) and a structural unit derived from a compound having a second functional group capable of reacting with the above-mentioned first functional group and a radiation-polymerizable functional group. When the acrylic polymer has such a structure, it is easy to design the following radiation-curable adhesive.

As the combination of the first functional group and the second functional group, for example, carboxyl and epoxy, epoxy and carboxyl, carboxyl and aziridine, aziridine and carboxyl, hydroxyl and isocyanate, isocyanate and hydroxyl, etc., can be cited. Among them, from the viewpoint of the ease of tracking the reaction, the combination of hydroxyl and isocyanate, and the combination of isocyanate and hydroxyl are preferred. Among them, the technical difficulty of preparing a polymer having an isocyanate group with high reactivity is particularly high. On the other hand, from the viewpoint of the ease of preparing and obtaining an acrylic polymer having a hydroxyl group, the combination in which the first functional group is a hydroxyl and the second functional group is an isocyanate is preferred.

The acrylic polymer having the above-mentioned structural part is particularly preferably a structural part having: a structural unit derived from a hydroxyl group-containing monomer, and a structural part derived from a compound having a radiation-polymerizable carbon-carbon double bond (especially a (meth)acryloyl group) and an isocyanate group.

Examples of the compound having a radiopolymerizable carbon-carbon double bond and an isocyanate group include methacrylic acid methyl acrylate, 2-acryloyloxyethyl isocyanate, 2-methacryloyloxyethyl isocyanate, and m-isopropenyl-α,α-dimethylbenzyl isocyanate. Among them, 2-acryloyloxyethyl isocyanate and 2-methacryloyloxyethyl isocyanate are preferred. In addition, examples of the acrylic polymer having a hydroxyl group include those containing structural units derived from the above-mentioned hydroxyl-containing monomers or ether compounds such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether.

The molar ratio [former/latter] of the structural unit derived from the monomer having the first functional group and the compound having the second functional group and the radiation polymerizable functional group is preferably 0.95 or more, more preferably 1.00 or more, more preferably 1.05 or more, and particularly preferably 1.10 or more. It is inferred that if the molar ratio is 0.95 or more, the bonding between the first functional group (e.g., hydroxyl group) and the second functional group (e.g., isocyanate group) is fully promoted, but despite this, the unreacted first functional group in the acrylic polymer in the adhesive layer still remains to a certain extent, thereby further improving the peeling force between the adhesive layer and the substrate, and making it less likely for the adhesive layer to break during expansion. The molar ratio may be, for example, 10.00 or less, 5.00 or less, 3.00 or less, 2.00 or less, 1.50 or less, or 1.30 or less.

It is particularly preferred that the molar ratio of the hydroxyl group-containing monomer to 2-methacryloyloxyethyl isocyanate [hydroxyl group-containing monomer/2-methacryloyloxyethyl isocyanate] is within the above range.

The acrylic polymer is obtained by polymerizing one or more monomer components including acrylic monomers. Examples of the polymerization method include solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization.

The adhesive layer or the adhesive forming the adhesive layer may also contain a crosslinking agent. For example, when an acrylic polymer is used as the base polymer, the acrylic polymer may be crosslinked to further reduce low molecular weight substances in the adhesive layer. In addition, the number average molecular weight of the acrylic polymer may be increased.

Examples of the crosslinking agent include polyisocyanate compounds, epoxy compounds, polyol compounds (polyphenol compounds, etc.), aziridine compounds, and melamine compounds. When a crosslinking agent is used, its usage amount is preferably about 5 parts by weight or less, more preferably 0.1 to 5 parts by weight, relative to 100 parts by weight of the base polymer.

The glass transition temperature (Tg) of the acrylic polymer (after crosslinking when a crosslinking agent is used) is preferably -50 to 10° C., more preferably -40 to 0° C. If the Tg is within the above range, it is easy to design an adhesive layer satisfying the above formula (1).

The mass average molecular weight of the acrylic polymer (after crosslinking when a crosslinking agent is used) is preferably 300,000 or more (e.g., 300,000 to 1.7 million), and more preferably 350,000 or more. If the mass average molecular weight is 300,000 or more, there is a tendency for less low molecular weight substances in the adhesive layer, which can further suppress contamination of the adhesive layer or semiconductor wafer.

The adhesive layer may be an adhesive layer capable of intentionally reducing the adhesive force by external action during the use of the wafer bonding film (adhesion-reducing adhesive layer), or an adhesive layer whose adhesive force is almost or not reduced at all by external action during the use of the wafer bonding film (adhesion-non-reducing adhesive layer). The adhesive layer may be appropriately selected according to the singulation method or conditions of the semiconductor wafers to be singulated using the wafer bonding film.

When the adhesive layer is an adhesive layer with reducible adhesion, during the manufacturing process or use process of the die-bonding film, it is possible to distinguish between a state where the adhesive layer exhibits relatively high adhesion and a state where the adhesive layer exhibits relatively low adhesion. For example, when the adhesive layer of a dicing tape is bonded to the bonding agent layer during the manufacturing process of a dicing adhesive film, or when the dicing adhesive film is used in a dicing step, the state in which the adhesive layer exhibits a relatively high adhesive force can be utilized to suppress and prevent the bonding agent layer and the like from floating up from the adhesive layer. On the other hand, in the picking-up step of the semiconductor chip to which the adhesive layer is attached from the dicing tape of the dicing adhesive film, the bonding agent layer can be easily picked up by reducing the adhesive force of the adhesive layer.

Examples of adhesives for forming such an adhesive layer with reduced adhesion include radiation-hardening adhesives and heat-foaming adhesives. As adhesives for forming the adhesive layer with reduced adhesion, one type of adhesive may be used, or two or more types of adhesives may be used.

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

Examples of the radiation-curable adhesive include additive-type radiation-curable adhesives containing a base polymer such as the acrylic polymer and a radiation-polymerizable monomer component or oligomer component having a functional group such as a radiation-polymerizable carbon-carbon double bond.

Examples of the radiation polymerizable monomer component include urethane (meth)acrylate, trihydroxymethylpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxy penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and 1,4-butanediol di(meth)acrylate.

Examples of the radiation polymerizable oligomer component include various oligomers such as urethane, polyether, polyester, polycarbonate, and polybutadiene. The molecular weight is preferably about 100 to 30,000.

The content of the radiation-curable monomer component and oligomer component in the radiation-curable adhesive forming the adhesive layer is, for example, 5 to 500 parts by mass, preferably about 40 to 150 parts by mass, relative to 100 parts by mass of the base polymer.

Furthermore, as an additive type radiation curable adhesive, for example, the one disclosed in Japanese Patent Laid-Open No. 60-196956 can be used.

As the radiation-curable adhesive, there can also be mentioned an intrinsic radiation-curable adhesive containing a base polymer having a radiation-polymerizable carbon-carbon double bond or other functional group in the polymer side chain or in the polymer main chain or at the polymer main chain terminal. If such an intrinsic radiation-curable adhesive is used, there is a tendency to suppress undesirable changes in adhesive properties over time caused by the migration of low molecular weight components in the formed adhesive layer.

The base polymer contained in the above-mentioned intrinsic radiation-curable adhesive is preferably an acrylic polymer. As a method for introducing radiation-polymerizable carbon-carbon double bonds into the acrylic polymer, for example, the following method can be cited: after polymerizing (copolymerizing) a raw material monomer containing the above-mentioned monomer component having the first functional group to obtain an acrylic polymer, the above-mentioned compound having the second functional group and the radiation-polymerizable carbon-carbon double bond is subjected to a condensation reaction or an addition reaction on the acrylic polymer while maintaining the radiation-polymerizable carbon-carbon double bond.

The radiation-curable adhesive preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include α-ketol compounds, acetophenone compounds, benzoin ether compounds, ketal compounds, aromatic sulfonyl chloride compounds, photoactive oxime compounds, benzophenone compounds, thioxanone compounds, camphorquinone, halogenated ketones, acylphosphine oxides, acyl phosphates, and the like.

Examples of the α-ketoalcohol compound include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, and 1-hydroxycyclohexylphenylketone.

Examples of the acetophenone compounds include methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, and 2-methyl-1-[4-(methylthio)-phenyl]-2-N-oxopropane-1.

Examples of the benzoin ether compounds include benzoin ethyl ether, benzoin isopropyl ether, and anisole methyl ether. Examples of the ketal compounds include benzoyl dimethyl ketal.

Examples of the aromatic sulfonyl chloride compound include 2-naphthalenesulfonyl chloride, etc. Examples of the optically active oxime compound include 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime, etc.

Examples of the benzophenone-based compound include benzophenone, benzoylbenzoic acid, and 3,3′-dimethyl-4-methoxybenzophenone.

Examples of the thiothione compounds include thiothione, 2-chlorothiothione, 2-methylthiothione, 2,4-dimethylthiothione, isopropylthiothione, 2,4-dichlorothiothione, 2,4-diethylthiothione, and 2,4-diisopropylthiothione.

The content of the photopolymerization initiator in the radiation-curable adhesive is, for example, 0.05 to 20 parts by mass relative to 100 parts by mass of the base polymer.

The heat-expandable adhesive is an adhesive containing a component (such as a foaming agent and heat-expandable microspheres) that foams or expands when heated.

Examples of the foaming agent include various inorganic foaming agents and organic foaming agents. Examples of the inorganic foaming agent include ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, ammonium nitrite, sodium borohydride, and azides. Examples of the organic foaming agent include fluorinated alkane such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate; hydrazine compounds such as p-toluenesulfonylhydrazine, diphenylsulfonium-3,3'-disulfonylhydrazine, 4,4'-oxybis(benzenesulfonylhydrazine), and allylbis(sulfonylhydrazine); amine urea compounds such as p-toluenesulfonylamine urea and 4,4'-oxybis(benzenesulfonylamine urea); triazole compounds such as 5-thiophene-1,2,3,4-thiatriazole; N-nitroso compounds such as N,N'-dinitrosopentamethylenetetramine and N,N'-dimethyl-N,N'-dinitrosoterephthalamide; and the like.

As the above-mentioned heat-expandable microspheres, for example, microspheres having a structure in which a substance that easily vaporizes and expands by heating is enclosed in a shell can be cited. As the above-mentioned substance that easily vaporizes and expands by heating, for example, isobutane, propane, pentane, etc. can be cited. Heat-expandable microspheres can be produced by enclosing a substance that easily vaporizes and expands by heating in a shell-forming substance using a coagulation method or an interfacial polymerization method. As the above-mentioned shell-forming substance, a substance that exhibits heat melting properties or a substance that can be broken due to the thermal expansion of the enclosed substance can be used. Examples of such substances include vinylidene chloride-acrylonitrile copolymers, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone.

As the above-mentioned adhesive layer with non-reduced adhesion, for example, a pressure-sensitive adhesive layer can be cited. Furthermore, the pressure-sensitive adhesive layer includes an adhesive layer of the following form, that is, an adhesive layer formed by the above-mentioned radiation-curable adhesive is hardened by radiation irradiation in advance, but has a certain adhesion. As an adhesive for forming the adhesive layer with non-reduced adhesion, one adhesive can be used, or two or more adhesives can be used.

The entire adhesive layer may be an adhesive layer of non-reducing adhesion, or a portion thereof may be an adhesive layer of non-reducing adhesion. For example, when the adhesive layer has a single-layer structure, the entire adhesive layer may be an adhesive layer of non-reducing adhesion, or a predetermined portion of the adhesive layer (e.g., a region outside the central region of the annular frame as a bonding target region) may be an adhesive layer of non-reducing adhesion, while the other portion (e.g., a central region of the bonding target region of the semiconductor wafer) may be an adhesive layer of reducible adhesion.

When the adhesive layer has a laminated structure, all adhesive layers in the laminated structure may be adhesive layers of a non-adhesion-reducing type, or a portion of adhesive layers in the laminated structure may be adhesive layers of a non-adhesion-reducing type.

Regarding the adhesive layer formed by the radiation-curing adhesive (radiation-curing adhesive layer not irradiated with radiation) which is hardened by radiation irradiation in advance (radiation-curing adhesive layer after radiation irradiation), even if the adhesive force is reduced by radiation irradiation, the adhesive force based on the polymer components contained therein is still exhibited, and the minimum adhesive force required for the adhesive layer of the dicing tape can be exerted in the dicing step, etc.

When a radiation-curing adhesive layer irradiated with radiation is used, the entire adhesive layer may be a radiation-curing adhesive layer irradiated with radiation, or a portion of the adhesive layer may be a radiation-curing adhesive layer irradiated with radiation and the other portion may be a radiation-unirradiated adhesive layer.

In this specification, the term "radiation-curable adhesive layer" refers to an adhesive layer formed by a radiation-curable adhesive, including both a radiation-curable adhesive layer that has not been irradiated with radiation and has radiation-curability and a radiation-curable adhesive layer that has been cured by irradiation with radiation.

As the adhesive forming the pressure-sensitive adhesive layer, a known or conventional pressure-sensitive adhesive can be used, and an acrylic adhesive or a rubber adhesive using an acrylic polymer as a base polymer can be preferably used. When the adhesive layer contains an acrylic polymer as the pressure-sensitive adhesive, the acrylic polymer is preferably a polymer containing a structural unit derived from (meth)acrylate as the largest structural unit in terms of mass ratio. As the acrylic polymer, for example, the acrylic polymer described as the acrylic polymer that can be contained in the adhesive layer can be used.

In addition to the above-mentioned components, the adhesive layer or the adhesive forming the adhesive layer may also be formulated with known or commonly used additives for adhesive layers, such as a crosslinking promoter, an adhesion imparting agent, an anti-aging agent, a coloring agent (pigment, dye, etc.).

As the coloring agent, for example, a compound that is colored by radiation irradiation can be cited. In the case of containing a compound that is colored by radiation irradiation, only the portion irradiated by radiation can be colored. The compound that is colored by radiation irradiation is a compound that is colorless or light-colored before radiation irradiation but becomes colored by radiation irradiation, and examples thereof include stealth dyes. The amount of the compound that is colored by radiation irradiation used is not particularly limited and can be appropriately selected.

The thickness of the adhesive layer is not particularly limited, but when the adhesive layer is formed of a radiation-curable adhesive, from the viewpoint of obtaining a balance in the adhesive force of the adhesive layer before and after radiation curing, it is preferably about 1 to 50 μm, more preferably 2 to 30 μm, and further preferably 5 to 25 μm.

(Adhesive layer) The adhesive layer has the function of being a heat-curing adhesive for die bonding, and further has the function of maintaining the adhesion between a workpiece such as a semiconductor wafer and a frame member such as a ring frame as needed. The adhesive layer can be cut by applying tensile stress, and can be used by cutting it by applying tensile stress.

The adhesive layer and the adhesive constituting the adhesive layer may contain a thermosetting resin and a thermoplastic resin as an adhesive component, for example, and may also contain a thermoplastic resin having a thermosetting functional group capable of reacting with the curing agent to form a bond. In the case where the adhesive constituting the adhesive layer contains a thermoplastic resin having a thermosetting functional group, the adhesive does not need to contain a thermosetting resin (epoxy resin, etc.). The adhesive layer may have a single-layer structure or a multi-layer structure.

Examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylate copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resin such as 6-nylon or 6,6-nylon, phenoxy resin, acrylic resin, saturated polyester resin such as PET or PBT, polyamide imide resin, fluororesin, etc. The thermoplastic resin may be used alone or in combination of two or more. As the thermoplastic resin, acrylic resin is preferred because it has less ionic impurities and higher heat resistance, and thus it is easy to ensure the bonding reliability based on the adhesive layer.

The acrylic resin preferably contains a structural unit derived from an alkyl-containing (meth)acrylate as the largest structural unit in terms of mass ratio. Examples of the alkyl-containing (meth)acrylate include the alkyl-containing (meth)acrylates exemplified as the alkyl-containing (meth)acrylates that form the acrylic polymer that may be contained in the adhesive layer.

The acrylic resin may also contain structural units derived from other monomer components that are copolymerizable with the alkyl-containing (meth)acrylate. Examples of the other monomer components include carboxyl-containing monomers, acid anhydride monomers, hydroxyl-containing monomers, glycidyl-containing monomers, sulfonic acid-containing monomers, phosphoric acid-containing monomers, acrylamide, acrylonitrile and other functional monomers, or various multifunctional monomers. Specifically, those exemplified as other monomer components constituting the acrylic polymer that may be contained in the adhesive layer may be used.

When the adhesive layer includes a thermoplastic resin and a thermosetting resin, the thermosetting resin may be, for example, an epoxy resin, a phenol resin, an amino resin, an unsaturated polyester resin, a polyurethane resin, a polysilicone resin, and a thermosetting polyimide resin. Only one type of the thermosetting resin may be used, or two or more types may be used. The thermosetting resin is preferably an epoxy resin because it tends to contain less ionic impurities that may cause corrosion of the semiconductor chip to be bonded. In addition, a phenol resin is preferably used as a hardener for the epoxy resin.

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 novolac type, o-cresol novolac type, trihydroxyphenylmethane type, tetraphenolethane type, hydantoin type, triglycidyl isocyanurate type, and glycidylamine type epoxy resins. Among them, from the viewpoint of being highly reactive with a phenolic resin as a hardener and having excellent heat resistance, a novolac type epoxy resin, a biphenyl type epoxy resin, a trihydroxyphenylmethane type epoxy resin, and a tetraphenolethane type epoxy resin are preferred.

Examples of phenolic resins that can function as a hardener for epoxy resins include novolac-type phenolic resins, resol-type phenolic resins, and polyhydroxystyrenes such as poly(p-hydroxystyrene). Examples of novolac-type phenolic resins include phenol novolac resins, phenol aralkyl resins, cresol novolac resins, tert-butylphenol novolac resins, and nonylphenol novolac resins. The above-mentioned phenolic resins may be used alone or in combination of two or more. Among them, when used as a hardener for an epoxy resin as a die-bonding adhesive, from the viewpoint of tending to improve the connection reliability of the adhesive, phenol novolac resin and phenol aralkyl resin are preferred.

In the adhesive layer, from the viewpoint of allowing the curing reaction of the epoxy resin and the phenol resin to proceed sufficiently, the phenol resin is contained in an amount of preferably 0.5 to 2.0 equivalents, more preferably 0.7 to 1.5 equivalents of hydroxyl groups in the phenol resin per 1 equivalent of epoxy groups in the epoxy resin component.

When the adhesive layer contains a thermosetting resin, from the viewpoint of appropriately expressing the function as a thermosetting adhesive in the adhesive layer, the content ratio of the thermosetting resin relative to the total mass of the adhesive layer is preferably 5 to 60 mass %, more preferably 10 to 50 mass %.

When the adhesive layer contains a thermoplastic resin having a thermosetting functional group, for example, an acrylic resin containing a thermosetting functional group can be used as the thermoplastic resin. The acrylic resin in the acrylic resin containing a thermosetting functional group preferably contains a structural unit derived from an alkyl-containing (meth)acrylate as the largest structural unit in terms of mass ratio. As the alkyl-containing (meth)acrylate, for example, the alkyl-containing (meth)acrylate exemplified as the alkyl-containing (meth)acrylate forming the acrylic polymer that can be contained in the adhesive layer can be cited.

On the other hand, as the thermosetting functional group in the acrylic resin containing a thermosetting functional group, for example, there can be cited: glycidyl group, carboxyl group, hydroxyl group, isocyanate group, etc. Among them, glycidyl group and carboxyl group are preferred. That is, as the acrylic resin containing a thermosetting functional group, glycidyl group-containing acrylic resin and carboxyl group-containing acrylic resin are particularly preferred.

Furthermore, it is preferred to contain an acrylic resin containing a thermosetting functional group and a hardener. As the hardener, for example, the crosslinking agent that can be contained in the radiation-curable adhesive for forming the adhesive layer can be cited. When the thermosetting functional group in the acrylic resin containing a thermosetting functional group is a glycidyl group, it is preferred to use a polyphenol compound as the hardener, for example, the various phenol resins mentioned above can be used.

In order to achieve a certain degree of crosslinking in the adhesive layer before hardening for die bonding, for example, it is preferred to pre-mix a multifunctional compound as a crosslinking component in the resin composition for forming the adhesive layer, and the multifunctional compound can react and bond with the functional groups at the ends of the molecular chains of the above-mentioned resins that may be contained in the adhesive layer. This structure is preferred from the perspective of improving the adhesive properties of the adhesive layer at high temperatures and also from the perspective of improving heat resistance.

As the crosslinking component, for example, a polyisocyanate compound can be cited. As the polyisocyanate compound, for example, toluene diisocyanate, diphenylmethane diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate, and an adduct of a polyol and a diisocyanate can be cited. In addition, as the crosslinking component, other polyfunctional compounds such as epoxy resins can also be used together with the polyisocyanate compound.

From the viewpoint of improving the cohesive force of the formed adhesive layer, the content of the crosslinking component in the adhesive layer-forming resin composition is preferably 0.05 parts by mass or more relative to 100 parts by mass of the resin having the functional group capable of reacting with the crosslinking component to form a bond, and from the viewpoint of improving the adhesive force of the formed adhesive layer, it is preferably 7 parts by mass or less.

The adhesive layer preferably contains a filler. By adding a filler to the adhesive layer, the electrical conductivity, thermal conductivity, elastic modulus and other physical properties of the adhesive layer can be adjusted. Examples of the filler include inorganic fillers and organic fillers, and inorganic fillers are particularly preferred.

Examples of inorganic fillers include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, boron nitride, crystalline silica, and amorphous silica, as well as metal single substances such as aluminum, gold, silver, copper, and nickel, or alloys, amorphous carbon black, and graphite. The filler may have various shapes such as spherical, needle-like, and flake-like. As the above fillers, only one type may be used, or two or more types may be used.

The average particle size of the filler is preferably 0.005 to 10 μm, more preferably 0.005 to 1 μm. If the average particle size is 0.005 μm or more, the wettability and adhesion to the adherend such as a semiconductor wafer are further improved. If the average particle size is 10 μm or less, the effect of the filler added to impart the above-mentioned characteristics can be fully achieved, and heat resistance can be ensured. Furthermore, the average particle size of the filler can be determined, for example, using a photometric particle size distribution meter (e.g., trade name "LA-910", manufactured by Horiba, Ltd.).

The adhesive layer may contain other components as needed. Examples of the other components include curing catalysts, flame retardants, silane coupling agents, ion scavengers, dyes, etc. The other additives may be used alone or in combination of two or more.

Examples of the flame retardant include antimony trioxide, antimony pentoxide, brominated epoxy resin, and the like.

Examples of the silane coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, and γ-glycidyloxypropylmethyldiethoxysilane.

Examples of the ion scavenger include magnesium aluminum carbonates, bismuth hydroxide, hydrous antimony oxide (e.g., "IXE-300" manufactured by Toagosei Co., Ltd.), zirconium phosphate with a specific structure (e.g., "IXE-100" manufactured by Toagosei Co., Ltd.), magnesium silicate (e.g., "KYOWAAD 600" manufactured by Kyowa Chemical Co., Ltd.), and aluminum silicate (e.g., "KYOWAAD 700" manufactured by Kyowa Chemical Co., Ltd.).

Compounds that can form complexes with metal ions can also be used as ion scavengers. Examples of such compounds include triazole compounds, tetrazole compounds, and bipyridine compounds. Among them, triazole compounds are preferred from the perspective of the stability of the complexes formed with metal ions.

Examples of the triazole compounds include 1,2,3-benzotriazole, 1-{N,N-bis(2-ethylhexyl)aminomethyl}benzotriazole, carboxybenzotriazole, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3,5-di-tert-pentylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, 6-(2-benzotriazolyl)-4-tert-octyl-6- '-tert-butyl-4'-methyl-2,2'-methylenebisphenol, 1-(2',3'-hydroxypropyl)benzotriazole, 1-(1,2-dicarboxydiethyl)benzotriazole, 1-(2-ethylhexylaminomethyl)benzotriazole, 2,4-di-tert-pentyl-6-{(H-benzotriazol-1-yl)methyl}phenol, 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole, 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy, 3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl ] octyl propionate, 3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionic acid 2-ethylhexyl ester, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, 2-(2H-benzotriazol-2-yl)-4-tert-butylphenol, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)-benzotriazole, 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzotriazole, 2-(2- 2-(2-Hydroxy-3,5-di-tert-pentylphenyl)benzotriazole, 2-(2-Hydroxy-3,5-di-tert-butylphenyl)-5-chloro-benzotriazole, 2-[2-Hydroxy-3,5-di(1,1-dimethylbenzyl)phenyl]-2H-benzotriazole, 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol, 2-[2-Hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, 3-[3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid methyl ester, etc.

In addition, specific hydroxyl-containing compounds such as hydroquinone compounds, hydroxyanthraquinone compounds, and polyphenol compounds can also be used as ion scavengers. Specific examples of such hydroxyl-containing compounds include 1,2-benzenediol, alizarin, anthracenol, tannin, gallic acid, methyl gallate, and pyrogallol.

The thickness of the adhesive layer (the total thickness in the case of a laminate) is not particularly limited, and is, for example, 1 to 200 μm. The upper limit is preferably 100 μm, more preferably 80 μm. The lower limit is preferably 3 μm, more preferably 5 μm.

In the wafer bonding film of the present invention, the peeling force between the adhesive layer and the adhesive layer in a T-type peeling test under the conditions of a temperature of 23°C and a peeling speed of 300 mm/min is preferably 0.3 N/20 mm or more, more preferably 0.5 N/20 mm or more, and further preferably 0.7 N/20 mm or more. If the peeling force is 0.3 N/20 mm or more, the adhesion between the adhesive layer and the adhesive layer can be made appropriate, and when the expansion step is performed without radiation curing, it is easy to suppress the peeling (lifting) between the adhesive layer and the adhesive layer during the expansion step and thereafter.

The higher the peeling force, the better. However, the upper limit may be, for example, 10 N/20 mm, 5.0 N/20 mm, or 3.0 N/20 mm. In addition, for a die-bonding film using a radiation-curable adhesive for the adhesive layer, the peeling force of the adhesive layer before radiation curing (peeling force in a T-type peeling test before UV curing) is preferably the above value.

In the wafer bonding film of the present invention, the peeling force between the adhesive layer and the bonding agent layer after radiation curing in a T-type peeling test under the conditions of a temperature of 23° C. and a peeling speed of 300 mm/min is preferably 0.3 N/20 mm or less, and more preferably 0.2 N/20 mm or less. If the peeling force is 0.3 N/20 mm or less, good picking up can be easily achieved in the picking up step performed after radiation curing.

The wafer bonding film may also have an isolation film. Specifically, each wafer bonding film may be in the form of a sheet of isolation film, or the isolation film may be in the form of a strip on which a plurality of wafer bonding films are arranged and the isolation film is wound to form a roll.

The isolation film is an element used to cover and protect the surface of the adhesive layer of the die-cutting die-bonding film, and is peeled off from the die-cutting die-bonding film when the die-cutting die-bonding film is used. Examples of the isolation film include polyethylene terephthalate (PET) film, polyethylene film, polypropylene film, plastic film or paper coated with a stripping agent such as a fluorine-based stripping agent or a long-chain alkyl acrylate-based stripping agent. The thickness of the isolation film is, for example, 5 to 200 μm.

The die-bonding film 1 as one embodiment of the die-bonding film of the present invention is manufactured, for example, in the following manner.

First, the substrate 11 can be obtained by film formation using a known or conventional film formation method. Examples of the film formation method include: calendering film formation, casting in an organic solvent, air extrusion in a closed system, T-die extrusion, co-extrusion, dry lamination, and the like.

Next, after coating the composition (adhesive composition) for forming the adhesive layer 12 on the substrate 11 to form a coating film, the coating film is cured by desolventizing or curing as needed to form the adhesive layer 12. The above-mentioned composition includes an adhesive and a solvent for forming the adhesive layer 12. As the above-mentioned coating method, for example, well-known or commonly used coating methods such as roll coating, screen coating, and gravure coating can be cited. In addition, as the desolventizing conditions, for example, the temperature is 80 to 150° C. and the time is 0.5 to 5 minutes.

Alternatively, after the adhesive composition is coated on the isolation film to form a coating film, the coating film may be cured under the above-mentioned desolventizing conditions to form the adhesive layer 12. Then, the adhesive layer 12 and the isolation film are bonded to the substrate 11. In this way, the dicing tape 10 can be manufactured.

Regarding the adhesive layer 20, first, a composition (adhesive composition) for forming the adhesive layer 20 including a resin, a filler, a curing catalyst, a solvent, etc. is prepared. Then, after the adhesive composition is applied on the isolation film to form a coating film, the coating film is cured by desolventizing or curing as needed to form the adhesive layer 20. There is no particular limitation on the coating method, and examples thereof include: roller coating, screen coating, gravure coating, and other well-known or commonly used coating methods. In addition, as the desolventizing conditions, for example, the temperature is 70 to 160°C and the time is 1 to 5 minutes.

Next, the isolation films are peeled off from the wafer-cutting tape 10 and the adhesive layer 20, respectively, and the adhesive layer 20 and the adhesive layer 12 are bonded in such a manner that the bonding surface is formed. The bonding can be performed, for example, by pressing. At this time, the lamination temperature is not particularly limited, for example, preferably 30 to 50°C, more preferably 35 to 45°C. In addition, the line pressure is not particularly limited, for example, preferably 0.1 to 20 kgf/cm, more preferably 1 to 10 kgf/cm.

As described above, when the adhesive layer 12 is a radiation-curing adhesive layer, after the adhesive layer 20 is attached, the adhesive layer 12 is irradiated with radiation such as ultraviolet rays, for example, from the substrate 11 side, and the irradiation amount is, for example, 50 to 500 mJ, preferably 100 to 300 mJ.

The area (irradiation area R) in the die-cutting die-bonding film 1 to be irradiated as a measure to reduce the adhesion of the adhesive layer 12 is generally the area except the peripheral portion in the bonding area of the adhesive layer 20 in the adhesive layer 12. When the irradiation area R is locally provided, it can be performed through a mask having a pattern corresponding to the area except the irradiation area R. Alternatively, a method of forming the irradiation area R by irradiating radiation in a point shape can be cited.

In this way, for example, the die-cutting die-bonding film 1 shown in FIG. 1 can be manufactured.

[Manufacturing method of semiconductor device] The wafer-cutting adhesive film of the present invention can be used to manufacture semiconductor devices. Specifically, the semiconductor device can be manufactured by a manufacturing method including the following steps: attaching a split body of a semiconductor wafer containing a plurality of semiconductor chips, or a semiconductor wafer capable of being singulated into a plurality of semiconductor chips, to the side of the adhesive layer in the wafer-cutting adhesive film of the present invention (sometimes referred to as "step A"); The dicing tape is expanded to at least cut the above-mentioned adhesive layer to form a semiconductor chip with an adhesive layer attached (sometimes referred to as "step B"); under relatively high temperature conditions, the above-mentioned dicing tape is expanded to expand the interval between the above-mentioned semiconductor chips with an adhesive layer attached (sometimes referred to as "step C"); and the above-mentioned semiconductor chip with an adhesive layer attached is picked up (sometimes referred to as "step D").

The above-mentioned split body of the semiconductor wafer containing a plurality of semiconductor chips used in step A, or the semiconductor wafer capable of being singulated into a plurality of semiconductor chips, can be obtained in the following manner. First, as shown in FIG. 2(a) and FIG. 2(b), a dividing groove 30a is formed on the semiconductor wafer W (dividing groove forming step). The semiconductor wafer W has a first surface Wa and a second surface Wb. Various semiconductor elements (not shown in the figure) have been manufactured on the first surface Wa side of the semiconductor wafer W, and the wiring structure required for the semiconductor element has been formed on the first surface Wa (not shown in the figure).

Then, after the wafer processing tape T1 having the adhesive surface T1a is attached to the second surface Wb side of the semiconductor wafer W, the semiconductor wafer W is held on the wafer processing tape T1, and a dividing groove 30a of a predetermined depth is formed on the first surface Wa side of the semiconductor wafer W using a rotating blade of a wafer cutting device or the like. The dividing groove 30a is a gap for separating the semiconductor wafer W into semiconductor chip units (in FIGS. 2 to 4 , the dividing groove 30a is schematically indicated by a thick solid line).

Next, as shown in FIG. 2( c ), the wafer processing tape T2 having the adhesive surface T2 a is attached to the first surface Wa side of the semiconductor wafer W, and the wafer processing tape T1 is peeled off from the semiconductor wafer W.

Then, as shown in FIG. 2( d ), the semiconductor wafer W is held on the wafer processing tape T2 and thinned by grinding from the second surface Wb until the semiconductor wafer W reaches a predetermined thickness (wafer thinning step). The grinding process can be performed using a grinding device equipped with a grinding stone. By the wafer thinning step, a semiconductor wafer 30A capable of being singulated into a plurality of semiconductor chips 31 is formed in the present embodiment.

Specifically, the semiconductor wafer 30A has a portion (connection portion) connecting portions of the wafer singulated into a plurality of semiconductor chips 31 on the second surface Wb side. The thickness of the connection portion in the semiconductor wafer 30A, that is, the distance between the second surface Wb of the semiconductor wafer 30A and the front end of the second surface Wb side of the dividing groove 30a, is, for example, 1 to 30 μm, preferably 3 to 20 μm.

(Step A) In step A, a semiconductor wafer containing a plurality of semiconductor chips or a semiconductor wafer capable of being singulated into a plurality of semiconductor chips is attached to the adhesive layer 20 side of the wafer bonding film 1.

In one embodiment of step A, as shown in FIG3(a), the semiconductor wafer 30A held by the wafer processing tape T2 is attached to the adhesive layer 20 of the die-cutting adhesive film 1. Then, as shown in FIG3(b), the wafer processing tape T2 is peeled off from the semiconductor wafer 30A.

Furthermore, after the semiconductor wafer 30A is bonded to the adhesive layer 20, the adhesive layer 12 may be irradiated with radiation such as ultraviolet rays from the substrate 11 side. The irradiation amount is, for example, 50 to 500 mJ/ ^cm2 , preferably 100 to 300 mJ/ ^cm2 . The irradiated area (irradiation area R shown in FIG. 1) in the die-bonding film 1 as a measure for reducing the adhesion of the adhesive layer 12 is, for example, an area of the adhesive layer 12 bonded to the adhesive layer 20 except for its peripheral portion.

(Step B) In step B, under relatively low temperature conditions, the wafer-cutting adhesive tape 10 in the wafer-cutting adhesive film 1 is expanded to at least cut the adhesive layer 20 to obtain a semiconductor chip with an adhesive layer attached.

In one embodiment of step B, first, after attaching the annular frame 41 to the adhesive layer 12 of the dicing tape 10 in the dicing adhesive film 1, as shown in FIG. 4(a), the dicing adhesive film 1 with the semiconductor wafer 30A attached is fixed to the holder 42 of the expansion device.

Next, as shown in FIG. 4( b ), the first expansion step (cold expansion step) is performed under relatively low temperature conditions to singulate the semiconductor wafer 30A into a plurality of semiconductor chips 31, and the adhesive layer 20 of the wafer-cutting adhesive film 1 is cut into small pieces of adhesive layer 21 to obtain semiconductor chips (31) with adhesive layers attached.

In the cold expansion step, the hollow cylindrical top member 43 of the expansion device is made to abut against the dicing tape 10 at the lower side of the dicing adhesive film 1 in the figure and rise, and the dicing tape 10 of the dicing adhesive film 1 bonded with the semiconductor wafer 30A is expanded by stretching in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer 30A.

The expansion is performed under the condition of generating a tensile stress in the range of 15 to 32 MPa, preferably 20 to 32 MPa, in the wafer-cutting tape 10. The temperature condition in the cold expansion step is, for example, below 0°C, preferably -20 to -5°C, more preferably -15 to -5°C, and more preferably -15°C. The expansion speed in the cold expansion step (the speed at which the lifting member 43 rises) is preferably 0.1 to 100 mm/sec. In addition, the expansion amount in the cold expansion step is preferably 3 to 16 mm.

In step B, when a semiconductor wafer 30A capable of being singulated into a plurality of semiconductor chips is used, the semiconductor wafer 30A is singulated into semiconductor chips 31 by cutting at a thin-walled and easily cracked portion. At the same time, in step B, the adhesive layer 20 that is in close contact with the adhesive layer 12 of the expanded dicing tape 10 suppresses deformation of each region where each semiconductor chip 31 is in close contact, while on the other hand, in a state where such deformation suppression effect is not produced, the tensile stress generated in the dicing tape 10 acts on the portion in the vertical direction of the dividing groove between the semiconductor chips 31. As a result, the portion in the adhesive layer 20 that is in the vertical direction of the dividing groove between the semiconductor chips 31 is cut. After the cutting is performed by expansion, as shown in FIG. 4( c ), the lifting member 43 is lowered to release the expanded state of the wafer-cutting tape 10 .

(Step C) In step C, the wafer cutting tape 10 is expanded under relatively high temperature conditions to expand the distance between the semiconductor chips attached with the adhesive layer.

In one embodiment of step C, first, as shown in FIG. 5( a ), a second expansion step (room temperature expansion step) is performed under relatively high temperature conditions to increase the distance (separation distance) between the semiconductor chips 31 to which the adhesive layer is attached.

In step C, the hollow cylindrical lifting member 43 of the expansion device is raised again to expand the wafer tape 10 of the wafer bonding film 1. The temperature condition in the second expansion step is, for example, above 10°C, preferably 15 to 30°C. The expansion speed in the second expansion step (the speed at which the lifting member 43 is raised) is, for example, 0.1 to 10 mm/sec, preferably 0.3 to 1 mm/sec. In step C, the separation distance of the semiconductor chip 31 with the adhesive layer attached is expanded to the extent that the semiconductor chip 31 with the adhesive layer attached can be properly picked up from the wafer tape 10 in the following picking up step. After the separation distance is enlarged by expansion, as shown in FIG. 5( b ), the lifting member 43 is lowered to release the expanded state of the dicing tape 10 .

From the viewpoint of suppressing the narrowing of the separation distance of the semiconductor chip 31 attached to the adhesive layer on the dicing tape 10 after the expansion state is released, it is preferable to heat and shrink the portion of the dicing tape 10 closer to the outside than the semiconductor chip 31 holding area before releasing the expansion state.

After step C, a cleaning step may be performed as needed, in which a cleaning liquid such as water is used to clean the semiconductor chip 31 side of the dicing tape 10 along with the semiconductor chip 31 with the adhesive layer attached thereto.

(Step D) In step D (pick-up step), the semiconductor chip with the adhesive layer attached that has been singulated is picked up. In one embodiment of step D, after the above-mentioned cleaning step is performed as necessary, as shown in FIG6 , the semiconductor chip 31 with the adhesive layer attached is picked up from the wafer tape 10. For example, for the semiconductor chip 31 with the adhesive layer attached that is the object of picking up, the pin member 44 of the picking mechanism is raised on the lower side of the wafer tape 10 in the figure and lifted up by the wafer tape 10, and then it is held by adsorption by the adsorption jig 45. In the picking-up step, the lifting speed of the pin member 44 is, for example, 1 to 100 mm/sec, and the lifting amount of the pin member 44 is, for example, 50 to 3000 μm.

The manufacturing method of the semiconductor device may also include other steps in addition to steps A to D. For example, in one embodiment, as shown in FIG. 7( a ), the picked-up semiconductor chip 31 with the adhesive layer attached is temporarily fixed on the adherend 51 via the adhesive layer 21 (temporary fixing step).

Examples of the adherend 51 include lead frames, TAB (Tape Automated Bonding) films, wiring substrates, and separately manufactured semiconductor chips. The shear bonding force of the adhesive layer 21 at 25°C when temporarily fixed is preferably 0.2 MPa or more, and more preferably 0.2 to 10 MPa relative to the adherend 51. The above-mentioned shear bonding force of the adhesive layer 21 being 0.2 MPa or more can suppress shear deformation caused by ultrasonic vibration or heating at the bonding surface between the adhesive layer 21 and the semiconductor chip 31 or the adherend 51 in the following wire bonding step, and wire bonding can be properly performed. Furthermore, the shear bonding force of the adhesive layer 21 at 175°C during temporary fixing relative to the adherend 51 is preferably 0.01 MPa or more, more preferably 0.01 to 5 MPa.

Next, as shown in FIG. 7( b ), the electrode pad (not shown) of the semiconductor chip 31 and the terminal portion (not shown) of the connected body 51 are electrically connected via the bonding wire 52 (wire bonding step).

The connection between the electrode pad of the semiconductor chip 31 or the terminal portion of the connected body 51 and the bonding wire 52 can be achieved by ultrasonic welding accompanied by heating, so as not to thermally harden the adhesive layer 21. As the bonding wire 52, for example, a gold wire, an aluminum wire, a copper wire, etc. can be used. The wire heating temperature in wire bonding is, for example, 80 to 250°C, preferably 80 to 220°C. In addition, the heating time is several seconds to several minutes.

Next, as shown in FIG. 7( c ), the semiconductor chip 31 is sealed by a sealing resin 53 for protecting the semiconductor chip 31 and the bonding wire 52 on the adherend 51 (sealing step).

In the sealing step, the adhesive layer 21 is thermally cured. In the sealing step, the sealing resin 53 is formed, for example, by a transfer molding technique using a mold. As a constituent material of the sealing resin 53, for example, an epoxy resin can be used. In the sealing step, the heating temperature for forming the sealing resin 53 is, for example, 165 to 185° C., and the heating time is, for example, 60 seconds to several minutes.

In the case where the sealing resin 53 is not sufficiently cured in the sealing step, a post-curing step is performed after the sealing step to completely cure the sealing resin 53. Even in the case where the adhesive layer 21 is not completely thermally cured in the sealing step, the adhesive layer 21 can be completely thermally cured together with the sealing resin 53 in the post-curing step. In the post-curing step, the heating temperature is, for example, 165 to 185° C., and the heating time is, for example, 0.5 to 8 hours.

In the above embodiment, as described above, after the semiconductor chip 31 with the adhesive layer attached is temporarily fixed to the adherend 51, the wire bonding step is performed without completely thermally curing the adhesive layer 21. Alternatively, in the above method for manufacturing a semiconductor device, after the semiconductor chip 31 with the adhesive layer attached is temporarily fixed to the adherend 51, the wire bonding step is performed after the adhesive layer 21 is thermally cured.

In the above-mentioned method for manufacturing a semiconductor device, as another embodiment, a wafer thinning step as shown in FIG8 may be performed instead of the wafer thinning step described above with reference to FIG2(d). After the process described above with reference to FIG2(c), in the wafer thinning step as shown in FIG8, the semiconductor wafer W is held on the wafer processing tape T2 and thinned by grinding from the second surface Wb until the wafer reaches a predetermined thickness, thereby forming a semiconductor wafer divided body 30B including a plurality of semiconductor chips 31 and held on the wafer processing tape T2.

In the wafer thinning step, the wafer may be ground until the dividing groove 30a is exposed on the second surface Wb side (first method), or the wafer may be ground from the second surface Wb side until it reaches the dividing groove 30a, and then a crack is generated between the dividing groove 30a and the second surface Wb by the pressure of the rotating grindstone on the wafer to form the semiconductor wafer divided body 30B (second method). The depth of the dividing groove 30a formed from the first surface Wa as described above with reference to FIG. 2 (a) and FIG. 2 (b) is appropriately determined according to the method adopted.

In Fig. 8, the dividing groove 30a formed by the first method or the dividing groove 30a formed by the second method and the cracks formed therefrom are schematically represented by thick solid lines. In the above-mentioned method for manufacturing a semiconductor device, in step A, the semiconductor wafer divided body 30B manufactured by the above-mentioned method may be used instead of the semiconductor wafer 30A as the semiconductor wafer divided body, and each step described above with reference to Figs. 3 to 7 may be performed.

FIG. 9( a ) and FIG. 9( b ) show step B in the embodiment, namely, the first expansion step (cold expansion step) performed after the semiconductor wafer segment 30B is attached to the wafer bonding film 1 .

In step B of the implementation form, the hollow cylindrical top member 43 of the expansion device is made to rise by abutting against the dicing tape 10 at the lower side of the dicing adhesive film 1 in the figure, and the dicing tape 10 of the dicing adhesive film 1 bonded with the semiconductor wafer separation body 30B is expanded by stretching in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer separation body 30B.

The expansion is performed under the condition of generating a tensile stress in the range of, for example, 5 to 28 MPa, preferably 8 to 25 MPa in the wafer-cutting tape 10. The temperature condition in the cold expansion step is, for example, below 0°C, preferably -20 to -5°C, more preferably -15 to -5°C, and more preferably -15°C. The expansion speed in the cold expansion step (the speed at which the lifting member 43 rises) is preferably 1 to 400 mm/sec. In addition, the expansion amount in the cold expansion step is preferably 50 to 200 mm.

According to this cold expansion step, the adhesive layer 20 of the dicing die attach film 1 is cut into small pieces of adhesive layer 21 to obtain semiconductor chips 31 with adhesive layers attached. Specifically, in the cold expansion step, in the adhesive layer 20 that is in close contact with the adhesive layer 12 of the dicing tape 10 being expanded, deformation of each region in close contact with each semiconductor chip 31 of the semiconductor wafer division body 30B is suppressed, while on the other hand, in the vertical direction of the dividing groove 30a between the semiconductor chips 31, the tensile stress generated in the dicing tape 10 acts without producing such deformation suppression effect. As a result, the portion of the resist layer 20 located in the vertical direction of the dividing groove 30a between the semiconductor chips 31 is cut.

In the above-mentioned method for manufacturing a semiconductor device, as another embodiment, a semiconductor wafer 30C manufactured in the following manner may be used instead of the semiconductor wafer 30A or the semiconductor wafer segment 30B used in step A.

In this embodiment, as shown in FIG. 10( a) and FIG. 10( b), first, a modified region 30 b is formed on a semiconductor wafer W. The semiconductor wafer W has a first surface Wa and a second surface Wb. Various semiconductor elements (not shown) have been fabricated on the first surface Wa side of the semiconductor wafer W, and wiring structures (not shown) required for the semiconductor elements have been formed on the first surface Wa.

Then, after the wafer processing tape T3 having the adhesive surface T3a is attached to the first surface Wa side of the semiconductor wafer W, the semiconductor wafer W is held on the wafer processing tape T3, and the laser light with the focal point directed to the inside of the wafer is irradiated to the semiconductor wafer W along the predetermined dividing line from the side opposite to the wafer processing tape T3, and a modified region 30b is formed in the semiconductor wafer W by etching based on multiphoton absorption. The modified region 30b is a fragile region used to separate the semiconductor wafer W into semiconductor chip units.

The method of forming the modified region 30b on the predetermined division line in the semiconductor wafer by laser light irradiation is described in detail in, for example, Japanese Patent Laid-Open No. 2002-192370, but the laser light irradiation conditions in this embodiment are appropriately adjusted within the range of the following conditions.

＜Laser light irradiation conditions＞ (A) Laser light source Semiconductor laser excitation Nd:YAG laser wavelength 1064 nm Laser light spot cross-sectional area 3.14×10 ^-8 cm ² Oscillation method Q switch Pulse repetition frequency 100 kHz or less Pulse width 1 μs or less Output 1 mJ or less Laser light quality TEM00 Polarization characteristics Linear polarization (B) Focusing lens magnification 100 times or less NA 0.55 Transmittance for laser light wavelength 100% or less (C) Movement speed of the stage for placing semiconductor substrate 280 mm/sec or less

Next, as shown in FIG. 10( c ), while the semiconductor wafer W is held on the wafer processing tape T3, it is thinned by grinding from the second surface Wb until the semiconductor wafer W reaches a specified thickness, thereby forming a semiconductor wafer 30C that can be singulated into a plurality of semiconductor chips 31 (wafer thinning step).

In the above-mentioned method for manufacturing a semiconductor device, in step A, the semiconductor wafer 30C manufactured in this way can be used instead of the semiconductor wafer 30A as a semiconductor wafer that can be singulated, and the steps described above with reference to FIG. 3 to FIG. 7 can be performed.

FIG. 11( a ) and FIG. 11( b ) show step B in the embodiment, namely, the first expansion step (cold expansion step) performed after the semiconductor wafer 30C is bonded to the die-bonding film 1 .

In the cold expansion step, the hollow cylindrical top member 43 of the expansion device is made to abut against the dicing tape 10 at the lower side of the dicing adhesive film 1 in the figure and rise, and the dicing tape 10 of the dicing adhesive film 1 bonded with the semiconductor wafer 30C is expanded by stretching in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer 30C.

The expansion is performed under the condition of generating a tensile stress in the range of, for example, 5 to 28 MPa, preferably 8 to 25 MPa in the wafer-cutting tape 10. The temperature condition in the cold expansion step is, for example, below 0°C, preferably -20 to -5°C, more preferably -15 to -5°C, and more preferably -15°C. The expansion speed in the cold expansion step (the speed at which the lifting member 43 rises) is preferably 1 to 400 mm/sec. In addition, the expansion amount in the cold expansion step is preferably 50 to 200 mm.

By this cold expansion step, the adhesive layer 20 of the die-cutting die-bonding film 1 is cut into small pieces of adhesive layer 21 to obtain the semiconductor chip 31 with the adhesive layer attached. Specifically, in the cold expansion step, cracks are formed in the fragile modified region 30b of the semiconductor wafer 30C to separate the semiconductor chips 31. At the same time, in the cold expansion step, in the adhesive layer 20 that is in close contact with the adhesive layer 12 of the expanded dicing tape 10, deformation of each region in close contact with each semiconductor chip 31 of the semiconductor wafer 30C is suppressed, while on the other hand, in the region in the vertical direction of the figure where cracks are formed in the wafer, the tensile stress generated in the dicing tape 10 acts without such deformation suppression. As a result, the region in the vertical direction of the figure where cracks are formed between the semiconductor chips 31 in the adhesive layer 20 is cut.

Furthermore, in the above-mentioned method for manufacturing a semiconductor device, the wafer-cutting adhesive film 1 can be used to obtain a semiconductor chip with an adhesive layer attached as described above, and can also be used to obtain a semiconductor chip with an adhesive layer attached when a plurality of semiconductor chips are stacked and three-dimensionally mounted. Between the semiconductor chips 31 in such a three-dimensional mounting, a spacer may be placed together with the adhesive layer 21, or a spacer may not be placed. [Example]

The present invention is described in more detail with reference to the following examples, but the present invention is not limited to the examples. The compositions of the monomer components constituting the acrylic polymer _P2 in the adhesive layer of the examples and comparative examples are shown in Table 1. In Table 1, the units of the numerical values representing the composition of the composition are as follows: the relevant numerical values of the monomer components are relative "mole", and the relevant numerical values of the components other than the monomer components are "parts by mass" relative to 100 parts by mass of the acrylic polymer _P2 .

Example 1 (Divided Resin Tape) In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirring device, a mixture containing 100 mol of 2-ethylhexyl acrylate (2EHA), 20 mol of 2-hydroxyethyl acrylate (HEA), 0.2 parts by mass of benzoyl peroxide as a polymerization initiator relative to 100 parts by mass of the total amount of the monomer components, and toluene as a polymerization solvent was stirred at 61° C. in a nitrogen atmosphere for 6 hours (polymerization reaction). A polymer solution containing an acrylic polymer _P1 was obtained.

Next, a mixture containing the polymer solution containing the acrylic polymer _P1 , 2-methacryloyloxyethyl isocyanate (MOI), and dibutyltin dilaurate as an addition reaction catalyst was stirred at 50°C in an air atmosphere for 48 hours (addition reaction). In the reaction solution, the amount of MOI was 18 mol. In addition, in the reaction solution, the amount of dibutyltin dilaurate was 0.01 parts by mass relative to 100 parts by mass of the acrylic polymer _P1 . By the addition reaction, a polymer solution containing an acrylic polymer _P2 having a methacrylate group on the side chain (an acrylic polymer containing a structural unit derived from an isocyanate compound containing an unsaturated functional group) was obtained.

Next, ₂ parts by mass of a polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) and 2 parts by mass of a photopolymerization initiator (trade name "IRGACURE 651", manufactured by BASF Corporation) were added to the polymer solution and mixed, and toluene was added to the mixture to dilute it in such a manner that the viscosity of the mixture at room temperature became 500 mPa·s to obtain an adhesive composition.

Next, an adhesive composition was applied on the silicone release treated surface of the PET separator film (50 μm thick) with an applicator to form an adhesive composition layer. Next, the composition layer was heated at 120° C. for 2 minutes to remove the solvent, thereby forming an adhesive layer with a thickness of 10 μm on the PET separator film.

Next, a polyolefin film (trade name "FUNCRARE NED #125", thickness 125 μm, manufactured by GUNZE Co., Ltd.) as a substrate with a corona-treated surface was bonded to the exposed surface of the adhesive layer at room temperature using a laminating press. The bonded body was then stored at 50° C. for 24 hours. Thus, the wafer-cutting tape of Example 1 was prepared.

(Adhesive layer) 100 parts by mass of acrylic polymer _A1 (trade name "Teisan Resin SG-P3", manufactured by Nagase Chemicals Co., Ltd.), 12 parts by mass of solid phenol resin (trade name "MEHC-7851SS", solid at 23°C, manufactured by Meiwa Chemicals Co., Ltd.), and 100 parts by mass of silica filler (trade name "SO-C2", average particle size of 0.5 μm, manufactured by Admatechs Co., Ltd.) were added to methyl ethyl ketone and mixed, and the concentration was adjusted so that the solid content concentration became 18% by mass to obtain an adhesive composition.

Next, the adhesive composition was applied on the silicone release treated surface of the PET separator film (50 μm thick) using an applicator to form a coating film, and the coating film was desolventized at 130° C. for 2 minutes. Thus, an adhesive layer with a thickness of 15 μm in Example 1 was prepared on the PET separator film.

(Preparation of wafer-cutting adhesive film) The PET isolation film is peeled off from the wafer-cutting adhesive tape of Example 1, and the adhesive layer of Example 1 is bonded to the exposed adhesive layer. A hand roller is used for bonding. In this way, the wafer-cutting adhesive film of Example 1 is prepared.

Example 2 In the preparation of the adhesive layer, the amount of the polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) was set to 1 part by weight. Otherwise, the wafer cutting tape and wafer cutting adhesive film of Example 2 were prepared in the same manner as in Example 1.

Example 3 In the preparation of the adhesive layer, the amount of the polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) was set to 0.5 parts by weight. Otherwise, the wafer cutting tape and wafer cutting adhesive film of Example 3 were prepared in the same manner as in Example 1.

Example 4 In the preparation of the adhesive layer, the amount of the polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) was set to 0.2 parts by weight. Otherwise, the wafer cutting tape and wafer cutting adhesive film of Example 4 were prepared in the same manner as in Example 1.

Example 5 (Divided Tape) In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirring device, a mixture containing 100 mol of 2-ethylhexyl acrylate (2EHA), 30 mol of 2-hydroxyethyl acrylate (HEA), 15 mol of acrylamide (AM), 0.2 parts by mass of benzoyl peroxide as a polymerization initiator relative to 100 parts by mass of the total amount of these monomer components, and toluene as a polymerization solvent was stirred at 61° C. in a nitrogen atmosphere for 6 hours (polymerization reaction). A polymer solution containing an acrylic polymer _P1 was obtained.

Next, a mixture containing the polymer solution containing the acrylic polymer _P1 , 2-methacryloyloxyethyl isocyanate (MOI), and dibutyltin dilaurate as an addition reaction catalyst was stirred at 50°C in an air atmosphere for 48 hours (addition reaction). The amount of MOI in the reaction solution was 25 mol. Furthermore, the amount of dibutyltin dilaurate in the reaction solution was 0.01 parts by mass relative to 100 parts by mass of the acrylic polymer _P1 . By the addition reaction, a polymer solution containing an acrylic polymer _P2 having a methacrylate group in the side chain (an acrylic polymer containing a structural unit derived from an isocyanate compound containing an unsaturated functional group) was obtained.

Next, ₂ parts by mass of a polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) and 2 parts by mass of a photopolymerization initiator (trade name "IRGACURE 651", manufactured by BASF Corporation) were added to the polymer solution and mixed, and toluene was added to dilute the mixture in such a manner that the viscosity of the mixture at room temperature became 500 mPa·s to obtain an adhesive composition.

Next, an adhesive composition was applied on the silicone release treated surface of the PET separator film (50 μm thick) using an applicator to form an adhesive composition layer. Next, the composition layer was heated at 120° C. for 2 minutes to remove the solvent, thereby forming an adhesive layer with a thickness of 10 μm on the PET separator film.

Next, a polyolefin film (trade name "FUNCRARE NED #125", thickness 125 μm, manufactured by GUNZE Co., Ltd.) as a substrate was bonded to the exposed surface of the adhesive layer at room temperature using a laminating press. The bonded body was then stored at 50°C for 24 hours. Thus, the wafer-cutting tape of Example 5 was prepared.

(Preparation of wafer-cutting adhesive film) The PET isolation film is peeled off from the wafer-cutting adhesive tape of Example 5, and the adhesive layer of Example 1 is bonded to the exposed adhesive layer. A hand roller is used for bonding. Thus, the wafer-cutting adhesive film of Example 5 is prepared.

Example 6 In the preparation of the adhesive layer, the amount of the polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) was set to 1 part by mass. Otherwise, the wafer cutting tape and wafer cutting adhesive film of Example 6 were prepared in the same manner as in Example 5.

Example 7 In the preparation of the adhesive layer, the amount of the polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) was set to 0.5 parts by weight. Otherwise, the wafer cutting tape and wafer cutting adhesive film of Example 7 were prepared in the same manner as in Example 5.

Example 8 In the preparation of the adhesive layer, the amount of the polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) was set to 0.2 parts by weight. Otherwise, the wafer cutting tape and wafer cutting adhesive film of Example 8 were prepared in the same manner as in Example 5.

Example 9 (Divided Tape) In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirring device, a mixture containing 100 mol of lauryl methacrylate (LMA), 15 mol of 2-hydroxyethyl methacrylate (HEMA), 0.2 parts by mass of benzoyl peroxide as a polymerization initiator relative to 100 parts by mass of the total amount of the monomer components, and toluene as a polymerization solvent was stirred at 61° C. in a nitrogen atmosphere for 6 hours (polymerization reaction). A polymer solution containing an acrylic polymer _P1 was obtained.

Next, a mixture containing the polymer solution containing the acrylic polymer _P1 , 2-methacryloyloxyethyl isocyanate (MOI), and dibutyltin dilaurate as an addition reaction catalyst was stirred at 50°C in an air atmosphere for 48 hours (addition reaction). The amount of MOI in the reaction solution was 12 mol. Furthermore, the amount of dibutyltin dilaurate in the reaction solution was 0.01 parts by mass relative to 100 parts by mass of the acrylic polymer _P1 . By the addition reaction, a polymer solution containing an acrylic polymer _P2 having a methacrylate group in the side chain (an acrylic polymer containing a structural unit derived from an isocyanate compound containing an unsaturated functional group) was obtained.

Next, ₂ parts by mass of a polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) and 2 parts by mass of a photopolymerization initiator (trade name "IRGACURE 651", manufactured by BASF Corporation) were added to the polymer solution and mixed, and toluene was added to dilute the mixture in such a manner that the viscosity of the mixture at room temperature became 500 mPa·s to obtain an adhesive composition.

Next, an adhesive composition was applied on the silicone release treated surface of the PET separator film (50 μm thick) with an applicator to form an adhesive composition layer. Next, the composition layer was heated at 120° C. for 2 minutes to remove the solvent, thereby forming an adhesive layer with a thickness of 10 μm on the PET separator film.

Next, a polyolefin film (trade name "FUNCRARE NED #125", thickness 125 μm, manufactured by GUNZE Co., Ltd.) as a substrate with a corona-treated surface was bonded to the exposed surface of the adhesive layer at room temperature using a laminating press. The bonded body was then stored at 50°C for 24 hours. The wafer-cutting tape of Example 9 was prepared in the above manner.

(Preparation of wafer-cutting adhesive film) The PET isolation film is peeled off from the wafer-cutting adhesive tape of Example 9, and the adhesive layer of Example 1 is bonded to the exposed adhesive layer. A hand roller is used for bonding. Thus, the wafer-cutting adhesive film of Example 9 is prepared.

Example 10 In the preparation of the adhesive layer, the amount of the polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) was set to 1 part by weight. Otherwise, the wafer cutting tape and wafer cutting adhesive film of Example 10 were prepared in the same manner as in Example 9.

Comparative Example 1 (Wafer-cut tape) In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirring device, a mixture containing 100 mol of lauryl methacrylate (LMA), 25 mol of 2-hydroxyethyl methacrylate (HEMA), 0.2 parts by mass of benzoyl peroxide as a polymerization initiator relative to 100 parts by mass of the total amount of the monomer components, and toluene as a polymerization solvent was stirred at 61° C. in a nitrogen atmosphere for 6 hours (polymerization reaction). A polymer solution containing an acrylic polymer _P1 was obtained.

Next, a mixture containing the polymer solution containing the acrylic polymer _P1 , 2-methacryloyloxyethyl isocyanate (MOI), and dibutyltin dilaurate as an addition reaction catalyst was stirred at 50°C in an air atmosphere for 48 hours (addition reaction). The amount of MOI in the reaction solution was 20 mol. Furthermore, the amount of dibutyltin dilaurate in the reaction solution was 0.01 parts by mass relative to 100 parts by mass of the acrylic polymer _P1 . A polymer solution containing an acrylic polymer _P2 having a methacrylate group in the side chain (an acrylic polymer containing a structural unit derived from an isocyanate compound containing an unsaturated functional group) was obtained by the addition reaction.

Next, _0.5 parts by mass of a polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) and 2 parts by mass of a photopolymerization initiator (trade name "IRGACURE 651", manufactured by BASF) were added to the polymer solution to mix with each other, and toluene was added to dilute the mixture so that the viscosity of the mixture at room temperature became 500 mPa·s to obtain an adhesive composition.

Next, an adhesive composition was applied on the silicone release treated surface of the PET separator film (50 μm thick) using an applicator to form an adhesive composition layer. Next, the composition layer was heated at 120° C. for 2 minutes to remove the solvent, thereby forming an adhesive layer with a thickness of 10 μm on the PET separator film.

Next, a polyolefin film (trade name "FUNCRARE NED #125", thickness 125 μm, manufactured by GUNZE Co., Ltd.) as a substrate was bonded to the exposed surface of the adhesive layer at room temperature using a laminating press. The bonded body was then stored at 50°C for 24 hours. Thus, the wafer-cutting tape of Comparative Example 1 was prepared.

(Preparation of wafer-cutting adhesive film) The PET isolation film is peeled off from the wafer-cutting adhesive tape of Comparative Example 1, and the adhesive layer of Example 1 is bonded to the exposed adhesive layer. A hand roller is used for bonding. Thus, the wafer-cutting adhesive film of Comparative Example 1 is prepared.

Comparative Example 2 In the preparation of the adhesive layer, the amount of the polyisocyanate compound (trade name "CORONATE L", manufactured by Tosoh Co., Ltd.) was set to 0.2 parts by weight. The wafer tape and wafer adhesive film of Comparative Example 2 were prepared in the same manner as Comparative Example 1.

Comparative Example 3 In laminating the adhesive layer and the substrate, a LDPE (Low-Density Polyethylene) film (thickness 100 μm, no surface treatment, manufactured by Nitto Denko Co., Ltd.) as the substrate was laminated to the exposed surface of the adhesive layer at room temperature using a laminating press. The laminated body was then stored at 50°C for 24 hours. The wafer-cutting tape and wafer-cutting adhesive film of Comparative Example 3 were prepared in the same manner as in Example 1 except that the laminated body was stored at 50°C for 24 hours.

Comparative Example 4 In laminating the adhesive layer and the substrate, a laminating press was used to laminate an LDPE film (100 μm thick, no surface treatment, manufactured by Nitto Denko Co., Ltd.) as the substrate to the exposed surface of the adhesive layer at room temperature. The laminated body was then stored at 50°C for 24 hours. Except for this, the wafer-cutting tape and wafer-cutting adhesive film of Comparative Example 3 were prepared in the same manner as in Example 4.

<Evaluation> The following evaluation was performed on the wafer-cutting and wafer-bonding films obtained in the embodiments and comparative examples.

(1) T-type peeling test For the die-bonding film obtained in the embodiment and the comparative example, the isolation film is peeled off to expose the die-bonding film surface. Then, a 50 mm wide backing tape (trade name "ELP BT315", manufactured by Nitto Denko Co., Ltd.) is attached to the exposed die-bonding film surface. A 20 mm wide × 120 mm long sample is cut from the die-bonding film attached with the backing tape as a measurement sample. Then, the peeling force between the substrate and the adhesive layer was measured by a T-type peeling test using the obtained test sample at a tensile speed of 300 mm/min at -15°C and 25°C. The results are shown in Table 1.

(2) Expansion evaluation Using the product name "ML300-Integration" (manufactured by Tokyo Seimitsu Co., Ltd.) as a laser processing device, the focal point was aligned with the inside of a 12-inch semiconductor wafer, and laser light was irradiated along the grid-shaped (8 mm×6 mm) predetermined dividing lines to form a modified area inside the semiconductor wafer. The laser light irradiation was performed under the following conditions.

(A) Laser light source Semiconductor laser excitation Nd: YAG laser wavelength 1064 nm Laser light spot cross-sectional area 3.14×10 ^-8 cm ² Oscillation method Q switch Pulse repetition frequency 100 kHz Pulse width 30 ns Output 20 μJ/pulse Laser light quality TEM00 40 Polarization characteristics Linear polarization (B) Focusing lens magnification 50 times NA 0.55 Transmittance relative to laser light wavelength 60% (C) Moving speed of the stage for placing semiconductor substrates 100 mm/sec

After the modified region was formed inside the semiconductor wafer, a protective tape for back grinding was attached to the surface of the semiconductor wafer, and the back side of the semiconductor wafer was ground using a back grinder (trade name "DGP8760", manufactured by DISCO Co., Ltd.) to a thickness of 30 μm.

The semiconductor wafer formed with the modified area is bonded to the dicing ring on the dicing adhesive film obtained in the embodiment and the comparative example (the bonding temperature is 60°C). Then, the semiconductor wafer and the adhesive film are cut using a separation expander (trade name "DDS2300", manufactured by DISCO Co., Ltd.). Specifically, first, the semiconductor wafer is cut by cold expansion in a cold expansion unit at a temperature of -15°C, an expansion speed of 300 mm/sec, and an expansion amount of 12 mm. Then, regarding the cracking of the adhesive layer, the case where there is cracking in the adhesive layer after cold expansion is evaluated as ×, and the case where there is no cracking is evaluated as ○. The results are shown in Table 1.

Then, in the heat expansion unit, expansion was performed at room temperature, expansion speed 1 mm/sec, expansion amount 9 mm, the distance between the heater and the wafer tape was set to 20 mm, the wafer tape was rotated at a rotation speed of 5°/sec, and the wafer tape at the top was thermally shrunk at 250°C. At this time, the number of edges of the semiconductor chip and the back protective film that were cut off was counted on the four sides of each semiconductor chip, and the ratio of the number of cut edges to the number of all edges was calculated as the cutting rate. The results are shown in Table 1.

[Table 1] (Table 1) Embodiment 1 Embodiment 2 Embodiment 3 Embodiment 4 Embodiment 5 Embodiment 6 Embodiment 7 Embodiment 8 Embodiment 9 Embodiment 10 Comparison Example 1 Comparison Example 2 Comparison Example 3 Comparison Example 4 Adhesive layer Acrylic polymer P ₂ 100 100 100 100 100 100 100 100 100 100 100 100 100 100 2EHA 100 100 100 100 100 100 100 100 - - - - 100 100 LMA - - - - - - - - 100 100 100 100 - - HEA 20 20 20 20 30 30 30 30 - - - - 20 20 HEMA - - - - - - - - 15 15 25 25 - - AM - - - - 15 15 15 15 - - - - - - MOI 18 18 18 18 25 25 25 25 12 12 20 20 18 18 Addition reaction catalyst (dibutyltin dilaurate) 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 Crosslinking agent (Coronate L) 2 1 0.5 0.2 2 1 0.5 0.2 2 1 0.5 0.2 2 0.2 Photopolymerization initiator (IRGACURE 651) 2 2 2 2 2 2 2 2 2 2 2 2 2 2 Substrate Corona Treatment have have have have have have have have have have have have without without Tg of acrylic polymer in adhesive layer [℃] -29 -30 -31 -32 -3 -4 -6 -7 0 0 2 2 -29 -32 [Hydroxy-containing monomer/MOI] (Molar ratio) 1.11 1.11 1.11 1.11 1.20 1.20 1.20 1.20 1.25 1.25 1.25 1.25 1.11 1.11 Peeling force at -15℃[N/10 mm] 9.2 9.1 9.7 11.4 15.3 16.1 16.2 16.6 7.0 6.7 6.2 6.3 0.38 0.59 Peeling force at 25℃[N/10 mm] 5.5 5.0 3.0 2.4 10.2 10.2 9.6 10.0 6.8 6.5 6.9 7.4 0.46 1.29 (Peeling force at -15℃)/(Peeling force at 25℃) 1.7 1.8 3.2 4.8 1.5 1.6 1.7 1.7 1.0 1.0 0.9 0.9 0.8 0.5 Cutting rate 100 100 100 100 100 100 100 100 100 100 98 97 92 85 Adhesive layer rupture ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ × × × ×

As a summary of the above, the structure and variations of the present invention are noted below. [1] A wafer-cutting adhesive film comprising: a wafer-cutting adhesive tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer that is releasably in close contact with the adhesive layer of the wafer-cutting adhesive tape; and the adhesive layer side surface of the substrate is surface-treated, and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15°C)/(Peeling force at 25°C)≧1 (1) [2] The wafer bonding film as described in [1], wherein the surface treatment is a corona treatment.

[3] A wafer bonding film comprising: a wafer bonding tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer releasably bonded to the adhesive layer of the wafer bonding tape; and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15°C)/(Peeling force at 25°C) ≧ 1 (1)

[4] The die-bonding film as described in any one of [1] to [3], wherein the peeling force between the substrate and the adhesive layer at -15°C exceeds 6.5 N/10 mm. [5] The die-bonding film as described in any one of [1] to [4], wherein the peeling force between the substrate and the adhesive layer at -15°C is 50 N/10 mm or less. [6] The die-bonding film as described in any one of [1] to [5], wherein the peeling force between the substrate and the adhesive layer at 35°C is 0.5 N/10 mm or more. [7] The die-cutting die-bonding film as described in any one of [1] to [6], wherein the peeling force between the substrate and the adhesive layer at 35° C. is less than 50 N/10 mm.

[8] The wafer-cut adhesive film as described in any one of [1] to [7], wherein the adhesive layer is an acrylic adhesive layer comprising an acrylic polymer as a base polymer. [9] The wafer-cut adhesive film as described in [8], wherein the acrylic polymer comprises a structural unit derived from a hydroxyl-containing monomer. [10] The wafer-cut adhesive film as described in [9], wherein the hydroxyl-containing monomer is 2-hydroxyethyl (meth)acrylate. [11] The wafer-cut adhesive film as described in [9] or [10], wherein the ratio of the hydroxyl-containing monomer in all monomer components used to form the acrylic polymer is 5 to 80 mol%. [12] The wafer-bonding film as described in any one of [8] to [11], wherein the acrylic polymer contains structural units derived from nitrogen-containing monomers (especially N-thiophene-containing monomers). [13] The wafer-bonding film as described in [12], wherein the nitrogen-containing monomer is (meth)acryloylthiophene. [14] The wafer-bonding film as described in [12] or [13], wherein the ratio of the nitrogen-containing monomer in all monomer components used to form the acrylic polymer is 3 to 50 mol%. [15] The wafer-bonding film as described in any one of [9] to [14], wherein the total ratio of the hydroxyl-containing monomer to the nitrogen-containing monomer in all monomer components used to form the acrylic polymer is 10 to 60 mol%.

[16] The die-cut adhesive film as described in any one of [8] to [15], wherein the acrylic polymer has: a structural unit derived from a monomer having a first functional group, and a structural unit derived from a compound having a second functional group capable of reacting with the first functional group and a radiation-polymerizable functional group. [17] The die-cut adhesive film as described in [16], wherein the combination of the first functional group and the second functional group is a combination of a hydroxyl group and an isocyanate group, or a combination of an isocyanate group and a hydroxyl group. [18] The die-cut adhesive film as described in [16], wherein the first functional group is a hydroxyl group and the second functional group is an isocyanate group. [19] The die-bonding film as described in any one of [16] to [18], wherein the compound having a second functional group and a radiation-polymerizable functional group is a compound having a radiation-polymerizable carbon-carbon double bond (especially a (meth)acryloyl group) and an isocyanate group. [20] The die-bonding film as described in any one of [16] to [18], wherein the compound having a second functional group and a radiation-polymerizable functional group is 2-acryloyloxyethyl isocyanate and/or 2-methacryloyloxyethyl isocyanate. [21] The die-bonding film as described in any one of [16] to [20], wherein the molar ratio of the structural unit derived from the monomer having the first functional group to the compound having the second functional group and a radiation-polymerizable functional group is 0.95 or more.

[22] The die-bonding film as described in any one of [8] to [21], wherein the glass transition temperature (Tg) of the acrylic polymer (after crosslinking when a crosslinking agent is used) is -50 to 10°C (especially -40 to 0°C).

[23] A die-cut adhesive film as described in any one of [1] to [22], wherein the adhesive layer contains a crosslinking agent (especially a polyisocyanate compound). [24] A die-cut adhesive film as described in [23], wherein the amount of the crosslinking agent used is 0.1 to 5 parts by weight relative to 100 parts by weight of the base polymer. [25] A die-cut adhesive film as described in any one of [1] to [24], wherein the adhesive layer contains a hardening catalyst (especially dibutyltin dilaurate).

[26] A wafer-cutting adhesive film, comprising: a wafer-cutting tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer releasably attached to the adhesive layer in the wafer-cutting tape; and the adhesive layer is an acrylic adhesive layer containing an acrylic polymer as a base polymer, wherein the acrylic polymer has a structural unit derived from a monomer having a first functional group and a structural unit derived from a monomer having a first functional group. The structural part of the compound having the second functional group and the radiation-polymerizable functional group capable of reacting with the first functional group, the molar ratio of the structural unit derived from the monomer having the first functional group to the compound having the second functional group and the radiation-polymerizable functional group is 0.95 or more, the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15°C)/(Peeling force at 25°C)≧1

[27] A wafer-cutting adhesive film, comprising: a wafer-cutting adhesive tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer which is releasably and closely attached to the adhesive layer in the wafer-cutting adhesive tape; and the adhesive layer is an acrylic adhesive layer containing an acrylic polymer as a base polymer, the glass transition temperature (Tg) of the acrylic polymer (after crosslinking when a crosslinking agent is used) being -50 to 10°C (particularly -40 to 0°C), and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15℃)/(Peeling force at 25℃)≧1

[28] A wafer bonding film, comprising: a wafer bonding tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer releasably bonded to the adhesive layer in the wafer bonding tape; and the peeling force between the substrate and the adhesive layer at -15°C exceeds 6.5 N/10 mm and is less than 50 N/10 mm, the peeling force between the substrate and the adhesive layer at 25°C exceeds 0.5 N/10 mm and is less than 50 N/10 mm, and the relationship between the peeling force between the substrate and the adhesive layer at -15°C and the peeling force at 25°C satisfies the following formula (1). (Peeling force at -15℃)/(Peeling force at 25℃)≧1

[29] A wafer-cutting tape having a laminated structure including a substrate and an adhesive layer, wherein the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15°C)/(Peeling force at 25°C) ≧ 1 (1) [30] A wafer-cutting tape as described in [29], wherein the surface of the substrate on the adhesive layer side is subjected to surface treatment (particularly corona treatment).

[31] The wafer-cutting tape as described in any one of [29] or [30], wherein the peeling force between the substrate and the adhesive layer at -15°C exceeds 6.5 N/10 mm. [32] The wafer-cutting tape as described in any one of [29] to [31], wherein the peeling force between the substrate and the adhesive layer at -15°C is 50 N/10 mm or less. [33] The wafer-cutting tape as described in any one of [29] to [32], wherein the peeling force between the substrate and the adhesive layer at 35°C is 0.5 N/10 mm or more. [34] The wafer-cutting tape as described in any one of [29] to [33], wherein the peeling force between the substrate and the adhesive layer at 35°C is less than 50 N/10 mm.

[35] The wafer-cutting tape as described in any one of [29] to [34], wherein the adhesive layer is an acrylic adhesive layer containing an acrylic polymer as a base polymer. [36] The wafer-cutting tape as described in [35], wherein the acrylic polymer contains structural units derived from hydroxyl-containing monomers. [37] The wafer-cutting tape as described in [36], wherein the hydroxyl-containing monomer is 2-hydroxyethyl (meth)acrylate. [38] The wafer-cutting tape as described in [36] or [37], wherein the ratio of the hydroxyl-containing monomer in all monomer components used to form the acrylic polymer is 5 to 80 mol%. [39] The wafer-cutting tape as described in any one of [35] to [38], wherein the acrylic polymer contains structural units derived from nitrogen-containing monomers (especially N-thiophene-containing monomers). [40] The wafer-cutting tape as described in [39], wherein the nitrogen-containing monomer is (meth)acryloylthiophene. [41] The wafer-cutting tape as described in [39] or [40], wherein the ratio of the nitrogen-containing monomer in all monomer components used to form the acrylic polymer is 3 to 50 mol%. [42] The wafer-cutting tape as described in any one of [35] to [41], wherein the total ratio of the hydroxyl-containing monomer to the nitrogen-containing monomer in all monomer components used to form the acrylic polymer is 10 to 60 mol%.

[43] The wafer-cutting tape as described in any one of [35] to [42], wherein the acrylic polymer has a structural unit derived from a monomer having a first functional group, and a structural unit derived from a compound having a second functional group capable of reacting with the first functional group and a radiation-polymerizable functional group. [44] The wafer-cutting tape as described in [43], wherein the combination of the first functional group and the second functional group is a combination of a hydroxyl group and an isocyanate group, or a combination of an isocyanate group and a hydroxyl group. [45] The wafer-cutting tape as described in [43], wherein the first functional group is a hydroxyl group and the second functional group is an isocyanate group. [46] The wafer-cutting tape as described in any one of [43] to [45], wherein the compound having a second functional group and a radiation-polymerizable functional group is a compound having a radiation-polymerizable carbon-carbon double bond (especially a (meth)acryl group) and an isocyanate group. [47] The wafer-cutting tape as described in any one of [43] to [45], wherein the compound having a second functional group and a radiation-polymerizable functional group is 2-acryloxyethyl isocyanate and/or 2-methacryloxyethyl isocyanate. [48] The wafer-cutting tape as described in any one of [43] to [47], wherein the molar ratio of the structural unit derived from the monomer having the first functional group to the compound having the second functional group and a radiation-polymerizable functional group is 0.95 or more.

[49] The wafer-cutting tape as described in any one of [35] to [48], wherein the glass transition temperature (Tg) of the acrylic polymer (after crosslinking when a crosslinking agent is used) is -50 to 10°C (especially -40 to 0°C).

[50] A wafer-cutting tape as described in any one of [29] to [49], wherein the adhesive layer contains a crosslinking agent (especially a polyisocyanate compound). [51] A wafer-cutting tape as described in [50], wherein the amount of the crosslinking agent used is 0.1 to 5 parts by weight relative to 100 parts by weight of the base polymer. [52] A wafer-cutting tape as described in any one of [29] to [51], wherein the adhesive layer contains a hardening catalyst (especially dibutyltin dilaurate).

[53] A wafer-cutting tape having a laminated structure including a substrate and an adhesive layer, wherein the surface of the substrate on the adhesive layer side is subjected to surface treatment, and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15°C)/(Peeling force at 25°C) ≧ 1 (1)

[54] A wafer-cutting tape having a laminated structure including a substrate and an adhesive layer, wherein the adhesive layer is an acrylic adhesive layer containing an acrylic polymer as a base polymer, the acrylic polymer having a structural unit derived from a monomer having a first functional group, and a structural unit derived from a compound having a second functional group capable of reacting with the first functional group and a radiation-polymerizable functional group, wherein the molar ratio of the structural unit derived from the monomer having the first functional group to the compound having the second functional group and the radiation-polymerizable functional group is greater than 0.95, and wherein the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15℃)/(Peeling force at 25℃)≧1

[55] A wafer-cutting tape having a laminate structure including a substrate and an adhesive layer, wherein the adhesive layer is an acrylic adhesive layer containing an acrylic polymer as a base polymer, the glass transition temperature (Tg) of the acrylic polymer (after crosslinking when a crosslinking agent is used) is -50 to 10°C (especially -40 to 0°C), and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1). (Peeling force at -15°C)/(Peeling force at 25°C) ≧ 1

[56] A wafer-cutting tape having a laminated structure including a substrate and an adhesive layer, and having an adhesive layer that is releasably bonded to the adhesive layer in the wafer-cutting tape, wherein the peeling force between the substrate and the adhesive layer at -15°C exceeds 6.5 N/10 mm and is less than 50 N/10 mm, the peeling force between the substrate and the adhesive layer at 25°C exceeds 0.5 N/10 mm and is less than 50 N/10 mm, and the relationship between the peeling force between the substrate and the adhesive layer at -15°C and the peeling force at 25°C satisfies the following formula (1). (Peeling force at -15℃)/(Peeling force at 25℃)≧1

1: Die-cutting adhesive film 10: Die-cutting tape 11: Substrate 11a: Surface 12: Adhesive layer 12a: Surface 20: Adhesive layer 21: Adhesive layer 30A: Semiconductor wafer 30a: Dividing groove 30B: Semiconductor wafer dividing body 30b: Modified area 30C: Semiconductor wafer 31: Semiconductor chip 41: Ring frame 42: Retaining member 43: Lifting member 44: Pin member 45: Adsorption fixture 51: Adhesive body 52: Bonding wire 53: Sealing resin R: Irradiation area T1: Wafer processing tape T1a: Adhesive surface T2: Wafer processing tape T2a: Adhesive surface T3: Wafer processing tape T3a: Adhesive surface W: Semiconductor wafer Wa: 1st surface Wb: 2nd surface

FIG. 1 is a cross-sectional schematic diagram showing an embodiment of the wafer-cutting die-bonding film of the present invention. FIG. 2(a) to (d) show a part of the steps in the method for manufacturing a semiconductor device using the wafer-cutting die-bonding film shown in FIG. FIG. 3(a) and (b) show the steps after the step shown in FIG. 2. FIG. 4(a) to (c) show the steps after the step shown in FIG. 3. FIG. 5(a) and (b) show the steps after the step shown in FIG. 4. FIG. 6 shows the steps after the step shown in FIG. 5. FIG. 7(a) to (c) show the steps after the step shown in FIG. 6. FIG. 8 shows a part of the steps in a variation of the method for manufacturing a semiconductor device using the wafer-cutting die-bonding film shown in FIG. 1. Fig. 9 (a) and (b) show some steps in a variation of a method for manufacturing a semiconductor device using the wafer-bonding film shown in Fig. 1. Fig. 10 (a) to (c) show some steps in a variation of a method for manufacturing a semiconductor device using the wafer-bonding film shown in Fig. 1. Fig. 11 (a) and (b) show some steps in a variation of a method for manufacturing a semiconductor device using the wafer-bonding film shown in Fig. 1.

1: Cutting and bonding film

10: Wafer cutting tape

11: Base material

11a: Surface

12: Adhesive layer

12a: Surface

20: Next is the agent layer

R: Irradiation area

Claims (3)

A wafer-cutting adhesive film comprises: a wafer-cutting tape having a laminated structure including a substrate and an adhesive layer; and an adhesive layer which is releasably bonded to the adhesive layer in the wafer-cutting tape; and the adhesive layer side surface of the substrate is surface-treated, and the relationship between the peeling force at -15°C and the peeling force at 25°C between the substrate and the adhesive layer satisfies the following formula (1), (peeling force at -15°C)/(peeling force at 25°C) ≧ 1 (1). The die-cutting die-bonding film of claim 1, wherein the peeling force between the substrate and the adhesive layer at -15°C exceeds 6.5 N/10 mm. The wafer-cutting adhesive film of claim 1 or 2, wherein the adhesive layer is an acrylic adhesive layer.