KR20210055602A - Dicing tape and dicing die-bonding film - Google Patents

Abstract

The present invention provides a dicing tape which comprises a base layer and an adhesive layer having higher adhesion compared to the base layer, has 20 to 120 J/cm^3 of volume crystallinity calculated from the differential scanning calorimetry of the base layer, and also has 80 μm or more of a thickness of the base layer. According to the dicing tape and a dicing die bonding film according to the present invention, a semiconductor wafer can be cut well in a low-temperature expand process.

Description

Dicing tape and dicing die-bonding film {DICING TAPE AND DICING DIE-BONDING FILM}

The present invention relates to, for example, a dicing tape used when manufacturing a semiconductor integrated circuit, and a dicing die-bonding film provided with the dicing tape.

Conventionally, dicing die bonding films used in the manufacture of semiconductor integrated circuits are known. This kind of dicing die-bonding film includes, for example, a dicing tape and a die-bonding layer laminated on the dicing tape and adhered to the wafer. The dicing tape has a base material layer and an adhesive layer in contact with the die bonding layer. This kind of dicing die-bonding film is used, for example, as follows in the manufacture of a semiconductor integrated circuit.

A method of manufacturing a semiconductor integrated circuit generally includes a pre-process of forming a circuit surface on one side of a wafer with a highly integrated electronic circuit, and a post-process of cutting a chip from a wafer on which the circuit surface is formed to perform assembly.

Post-processes include, for example, a dicing process in which grooves are formed in the wafer in order to cut the wafer into small chips (die), and the side opposite to the circuit surface of the wafer is attached to the die bonding layer, and the wafer is applied to the dicing tape. The mounting process of fixing the grooves, the expanding process of dividing the wafer with the grooves together with the die bond layer to widen the gap between the chips, and the chip in a state where the die bond layer is affixed by peeling between the die bond layer and the pressure-sensitive adhesive layer ( A pick-up step of taking out a die) and a die bonding step of adhering a chip (die) in a state in which the die-bonding layer is affixed to the adherend are provided. The semiconductor integrated circuit is manufactured through these processes.

In the above manufacturing method, in the expand process, for example, in a state in which the wafer is disposed on the die bond layer overlaid on the dicing tape, the dicing tape is stretched in the radial direction at a low temperature such as below the freezing point, and further stretched at room temperature. As a result, the gap (cuff) between adjacent chips (die) is widened. After that, in order to maintain the gap (cuff), a part of the dicing tape which has been stretched and lowered in tension is subjected to heat shrinkage (heat shrink). Specifically, the dicing tape in the outer portion of the portion that overlaps the cut chip (die) is heat-shrunk, and thereby the gap (cuff) can be maintained.

By the way, in the expansion process performed under low temperature conditions, there are cases where it is not possible to divide the semiconductor wafer and the die bond layer at once. In order to prevent such a problem, the dicing tape is required to have a performance capable of satisfactorily cutting a semiconductor wafer by an expand process under low temperature conditions.

On the other hand, as a conventional dicing tape, for example, it is known that the initial elastic modulus at -10°C is 200 MPa or more and 380 MPa or less, and Tanδ (loss elastic modulus/storage elastic modulus) at -10°C is 0.080 or more and 0.3 or less. (Patent Document 1).

According to the dicing tape described in Patent Document 1, when used in a state where the semiconductor wafer is affixed through the die-bonding layer, the semiconductor wafer and the die-bonding layer can be cut together by an expand process performed under low temperature conditions. have.

Japanese Patent Publication No. 2015-185591

However, it cannot be said that a dicing die-bonding film or a dicing tape capable of satisfactorily cutting a semiconductor wafer in a low-temperature expansion process has been sufficiently studied yet.

Therefore, it is an object of the present invention to provide a dicing tape and a dicing die-bonding film capable of satisfactorily cutting a semiconductor wafer in a low-temperature expansion process.

In order to solve the above problems, the dicing tape according to the present invention includes a substrate layer and a pressure-sensitive adhesive layer having higher adhesion than the substrate layer,

The volume crystallinity calculated from the differential scanning calorimetry result of the base layer is 20 J/cm 3 or more and 120 J/cm 3 or less, and the base layer has a thickness of 80 μm or more.

The dicing tape of the above-described configuration can satisfactorily cut semiconductor wafers in a low-temperature expansion process.

In the dicing tape, the chart in which the base layer is measured by differential scanning calorimetry has an endothermic peak, and the peak temperature of the endothermic peak is preferably 100°C or higher. As a result, since the crystallinity of the substrate layer becomes higher, there is an advantage that the mechanical energy due to the expansion can be transmitted more efficiently in the substrate layer.

A dicing die-bonding film according to the present invention includes the dicing tape and a die-bonding layer bonded to the dicing tape.

According to the dicing tape and the dicing die-bonding film according to the present invention, a semiconductor wafer can be satisfactorily cut in a low-temperature expansion process.

1 is a cross-sectional view taken along a thickness direction of a dicing die-bonding film of this embodiment.
Fig. 2A is a cross-sectional view schematically showing a state of half-cut processing in a method for manufacturing a semiconductor integrated circuit.
Fig. 2B is a cross-sectional view schematically showing a state of half-cut processing in a method for manufacturing a semiconductor integrated circuit.
Fig. 2C is a cross-sectional view schematically showing a state of half-cut processing in a method for manufacturing a semiconductor integrated circuit.
Fig. 2D is a cross-sectional view schematically showing a state of half-cut processing in a method for manufacturing a semiconductor integrated circuit.
3A is a cross-sectional view schematically showing a state of a mounting process in a method for manufacturing a semiconductor integrated circuit.
3B is a cross-sectional view schematically showing a state of a mounting process in a method for manufacturing a semiconductor integrated circuit.
4A is a cross-sectional view schematically showing a state of an expand process at a low temperature in a method for manufacturing a semiconductor integrated circuit.
4B is a cross-sectional view schematically showing a state of an expand process at a low temperature in a method for manufacturing a semiconductor integrated circuit.
4C is a cross-sectional view schematically showing a state of an expand process at a low temperature in a method for manufacturing a semiconductor integrated circuit.
5A is a cross-sectional view schematically showing a state of an expand process at room temperature in a method for manufacturing a semiconductor integrated circuit.
5B is a cross-sectional view schematically showing a state of an expanding process at room temperature in a method for manufacturing a semiconductor integrated circuit.
Fig. 6 is a cross-sectional view schematically showing a pickup step in a method for manufacturing a semiconductor integrated circuit.
Fig. 7A is a first chart showing an example of differential scanning calorimetry (Example 1).
Fig. 7B is a second chart showing an example of differential scanning calorimetry (Example 1).
Fig. 8A is a first chart showing an example of differential scanning calorimetry (Comparative Example 1).
Fig. 8B is a second chart showing an example of differential scanning calorimetry (Comparative Example 1).

Hereinafter, an embodiment of a dicing die-bonding film and a dicing tape according to the present invention will be described with reference to the drawings.

The dicing die-bonding film 1 of this embodiment is a dicing tape 20 and a die-bonding layer 10 laminated on the pressure-sensitive adhesive layer 22 of the dicing tape 20 and adhered to a semiconductor wafer. It is equipped with.

The dicing tape 20 of this embodiment is usually a long sheet, and is stored in a wound state until used. The dicing die-bonding film 1 of the present embodiment is applied to an annular frame having an inner diameter that is one step larger than that of a silicon wafer to be cut, and then cut and used.

The dicing tape 20 of the present embodiment includes a base layer 21 and a pressure-sensitive adhesive layer 22 overlaid on the base layer 21.

In the dicing tape 20 of the present embodiment, the volume crystallinity calculated from the differential scanning calorimetry result of the base layer 21 is 20 J/cm 3 or more and 120 J/cm 3 or less, and the thickness of the base layer 21 is It is 80㎛ or more.

Since the dicing tape 20 of the present embodiment has the above configuration, it is possible to satisfactorily cut a semiconductor wafer in a low-temperature expansion process.

The volume crystallinity is a value obtained based on the measurement result of performing differential scanning calorimetry (DSC measurement) on the base layer 21.

Specifically, the differential scanning calorimetry (DSC measurement) of the substrate layer 21 is performed according to the following measurement conditions. The volume crystallinity calculated as follows is obtained from the chart obtained in one measurement.

Specifically, about 10 mg of a measurement sample is weighed using a commercially available DSC measuring device, and the measurement is carried out in a nitrogen gas atmosphere from room temperature (about 20° C.) to 200° C. at a heating rate of 5° C./min. . The measurement sample is produced by cutting the substrate layer 21 in the thickness direction.

The endothermic amount is calculated from the area of the endothermic peak shown in the chart obtained by differential scanning calorimetry (DSC measurement). The area of the endothermic peak is calculated by obtaining an area surrounded by a base line connecting a point on the low-temperature side and a point on the high-temperature side where there is no change in the amount of heat in the peak, and a curve line drawing an endothermic peak. The calculation of the endothermic amount is performed based on the endothermic peak accompanying melting. The calculated endothermic amount is converted into a value per volume. Further, in the case where the base layer 21 is composed of a plurality of layers of different materials, etc., a plurality of endothermic peaks may appear in the measurement chart. When calculating the amount of heat absorbing, the amount of heat absorbing is calculated from the area of each endothermic peak attributable to each layer, and the sum of the total amount of heat absorbed is divided by the total volume of the base layer 21. It is adopted as the volume crystallinity.

The area of the endothermic peak shown in the measurement chart is calculated by the analysis software attached to the DSC measuring device.

In addition, although an exothermic peak or a curve due to a glass transition point may appear in the measurement chart, these are not treated as endothermic peaks.

In addition, each temperature of the peak start point of the endothermic peak shown in the measurement chart (hereinafter, simply referred to as point A), the peak point of the peak (hereinafter, referred to simply as point C), and the peak end point (hereinafter referred to simply as point B) Is measured by the analysis software attached to the DSC measuring device.

Most preferably, the area of the endothermic peak, the peak start point, the peak peak, and the end point of the peak are based on the measurement results using a specific DSC measurement device described in the following examples, and are based on the specific analysis software described in the following examples. Is obtained by

If the volume crystallinity is less than 20 J/cm 3, there is a concern that the cleavage property may be poor because the crystallinity of the base layer 21 is insufficient. On the other hand, if the volume crystallinity is greater than 120 J/cm 3, the crystallinity of the base layer 21 is too high, and there is a fear that the base layer 21 may rupture during expansion.

The volume crystallinity is preferably 25 J/cm 3 or more, more preferably 26 J/cm 3 or more, and even more preferably 30 J/cm 3 or more. Thereby, there is an advantage that more favorable cleaving properties are exhibited in the low-temperature expansion process.

The volume crystallinity is preferably 100 J/cm 3 or less, more preferably 90 J/cm 3 or less, and even more preferably 82 J/cm 3 or less. Thereby, there is an advantage that the rupture of the base material layer 21 at the time of expansion is more suppressed.

For example, the volume crystallinity can be further increased by forming the base layer 21 from a resin material having a higher crystallinity, or by performing slow cooling treatment or stretching treatment at the time of production of the base layer 21. On the other hand, for example, by forming the base layer 21 from a resin material with a lower crystallinity, or by performing a rapid cooling treatment or not performing a stretching treatment at the time of manufacture of the base layer 21, the volume crystallinity can be reduced. I can.

The chart obtained by measuring the substrate layer 21 by differential scanning calorimetry (DSC) preferably has an endothermic peak having a peak (point C) in a range of 100°C or more and 140°C or less. Such an endothermic peak is, for example, an endothermic peak that appears with melting of the resin.

Since the apex (point C) of the endothermic peak is present at 100° C. or higher, there is an advantage in that the cuff can be maintained by rapidly solidifying after the end of the heat shrink. In addition, there is an advantage in that more favorable cleaving properties are exhibited. It is more preferable that the peak (point C) of the endothermic peak is present at 105°C or higher.

Since the peak (point C) of the endothermic peak is present at 140° C. or lower, there is an advantage in that heat shrinkage can be sufficiently performed during heat shrinking. It is more preferable that the peak (point C) of the endothermic peak exists at 135°C or lower.

In addition, when there are a plurality of endothermic peaks in the range of 100°C or more and 140°C or less, it is preferable that at least one of these endothermic peaks satisfy the above condition (peak peak). Similarly, it is preferable that at least one endothermic peak satisfies the following conditions (peak start point, end point, etc.).

For example, to form the base layer 21 from a resin material having a higher melting point, or to construct the base layer 21 of a laminated structure by using a layer of a resin material with a higher melting point, or to use a resin material with a higher melting point. By blending (blending) in the base layer 21, the peak (point C) of the endothermic peak can be shifted to a higher temperature. On the other hand, for example, the base layer 21 is formed of a resin material having a lower melting point, or a layer of a resin material having a lower melting point is used to form the base layer 21 of a laminated structure, or a resin material having a lower melting point By blending (blending) into the base layer 21, the temperature of the peak (point C) of the endothermic peak can be shifted to a lower temperature.

The temperature difference between the peak initiation point (point A) and the peak (point C) in the endothermic peak is preferably 40°C or less, and more preferably 35°C or less.

Since this temperature difference is 40° C. or less, the melting of the base layer 21 can be completed with a smaller (narrow) temperature difference. Therefore, it is possible to solidify and soften the base layer 21 with a smaller temperature difference. Therefore, the base layer 21 is thermally contracted (heat shrink) after expansion, and rapidly solidified after the heat shrink is completed, so that it is possible to efficiently maintain the spacing (cuff) between adjacent chips (die). .

The temperature difference between the peak start point (point A) and the peak (point C) in the endothermic peak may be 20°C or higher.

For example, by increasing the molecular weight dispersion degree of the resin (polymer) contained in the base layer 21, the temperature difference between the peak initiation point (point A) and the peak (point C) in the endothermic peak can be made larger. have.

For example, by making the molecular weight dispersion degree of the resin (polymer) contained in the base layer 21 smaller, the temperature difference between the peak initiation point (point A) and the peak (point C) in the endothermic peak can be made smaller. I can.

In the dicing tape, in the endothermic peak of the base layer 21, the temperature difference between the peak start point (point A) and the peak end point (point B) is preferably 60°C or less, and more preferably 50°C or less. . When such a temperature difference is 60° C. or less, the temperature difference from the start of the melting to the end of the melting of the base layer 21 becomes smaller, so that solidification and softening of the base layer 21 can be performed at a smaller temperature difference. Accordingly, there is an advantage in that the above-described heat contraction performed after expansion can be efficiently performed.

Such a temperature difference may be 30°C or higher.

For example, by making the molecular weight dispersion degree of the resin (polymer) contained in the base material layer 21 smaller, the temperature difference between a peak start point (A point) and a peak end point (B point) can be made smaller. On the other hand, for example, by increasing the molecular weight dispersion degree of the resin (polymer) contained in the base layer 21, the temperature difference between the peak start point (point A) and the peak end point (point B) can be made larger.

In the dicing tape, in the endothermic peak of the base layer 21, the temperature of the peak starting point (point A) is preferably 70°C or higher, and more preferably 80°C or higher. The peak initiation point (point A) is an index of the temperature at which solidification of the base layer 21 is completed, and when the temperature of the peak initiation point is 70°C or higher, the base layer 21 once softened by the heater is cooled. It starts and finishes solidification at a relatively high temperature. If the temperature is lower than 70° C., since solidification of the base layer 21 is completed, the above-described thermal contraction after expansion can be sufficiently performed. Therefore, it is possible to efficiently maintain the cuff after expansion.

The temperature of the peak initiation point (point A) may be 110°C or less, or 100°C or less.

For example, to form the base layer 21 from a resin material having a higher melting point, or to construct the base layer 21 of a laminated structure by using a layer of a resin material with a higher melting point, or to use a resin material with a higher melting point. By blending (blending) in the base layer 21, the temperature of the peak initiation point (point A) can be shifted to a higher temperature. On the other hand, for example, the base layer 21 is formed of a resin material having a lower melting point, or a layer of a resin material having a lower melting point is used to form the base layer 21 of a laminated structure, or a resin material having a lower melting point By blending (blending) into the base layer 21, the temperature of the peak initiation point (point A) can be shifted to a lower temperature.

In the dicing tape, in the endothermic peak of the base layer 21, the temperature at the peak end point (point B) is preferably 150°C or less, and more preferably 140°C or less. The peak end point (point B) is an index of the temperature at which the softening of the base layer 21 is completed, and if the temperature at the peak end point is 150°C or less, even if the heating temperature of the heater is slightly lower or higher than 150°C, the base material The layer 21 is sufficiently softened. Therefore, even if the heating temperature for softening is slightly low, since the above-described heat contraction can be efficiently performed, it is possible to efficiently maintain the cuff after expansion.

The temperature at the peak end point (point B) may be 110°C or higher, or 120°C or higher.

For example, to form the base layer 21 of a resin material with a lower melting point, or to form the base layer 21 of a laminated structure by using a layer of a resin material with a lower melting point, or a resin material with a lower melting point. By blending (blending) in the base layer 21, the temperature of the peak end point (point B) can be shifted to a lower temperature. On the other hand, for example, the base layer 21 is formed of a resin material having a higher melting point, or a layer of a resin material having a higher melting point is used to form the base layer 21 of a laminated structure, or a resin material having a higher melting point By blending (blending) into the base layer 21, the temperature of the peak end point (point B) can be shifted to a higher temperature.

The base material layer 21 may have a single-layer structure or may have a laminated structure.

Each layer of the base material layer 21 is, for example, a metal foil, a fiber sheet such as paper or cloth, a rubber sheet, a resin film, or the like.

Paper, woven fabric, nonwoven fabric, etc. are mentioned as a fiber sheet which comprises the base material layer 21.

Examples of the material of the resin film include polyolefins such as polyethylene (PE), polypropylene (PP), and ethylene-propylene copolymer; Ethylene copolymers such as ethylene-vinyl acetate copolymer (EVA), ionomer resin, ethylene-(meth)acrylic acid copolymer, and ethylene-(meth)acrylic acid ester (random, alternating) copolymer; Polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); Polyacrylate; Polyvinyl chloride (PVC); Polyurethane; Polycarbonate; Polyphenylene sulfide (PPS); Polyamides such as aliphatic polyamide and wholly aromatic polyamide (aramid); Polyetheretherketone (PEEK); Polyimide; Polyetherimide; Polyvinylidene chloride; ABS (acrylonitrile-butadiene-styrene copolymer); Cellulose or cellulose derivatives; Silicone-containing polymer; And fluorine-containing polymers. These may be used alone or in combination of two or more.

It is preferable that the base material layer 21 is made of a polymer material such as a resin film.

When the base material layer 21 has a resin film, the resin film may be subjected to a stretching treatment or the like to control deformability such as elongation.

The surface of the substrate layer 21 may be subjected to a surface treatment in order to increase the adhesion with the pressure-sensitive adhesive layer 22. As the surface treatment, for example, a chemical method such as chromic acid treatment, ozone exposure, flame exposure, high-pressure electric shock exposure, ionizing radiation treatment, or an oxidation treatment by a physical method may be employed. Further, coating treatment with a coating agent such as an anchor coating agent, a primer, or an adhesive may be performed.

The base material layer 21 is preferably composed of a plurality of layers, more preferably composed of at least three layers, and even more preferably composed of three layers.

Since the base layer 21 has a stacked structure of a plurality of layers (for example, a three-layer structure), it becomes possible to stack a layer having a lower elastic modulus than a layer having a higher elastic modulus, so that the base layer 21 is relatively simple. There is an advantage that the modulus of elasticity of can be controlled. For example, in the case of a substrate layer having only a layer having a relatively high elastic modulus, in the expansion process, chips may be lifted or the substrate may be ruptured. Further, for example, in the case of a base layer having only a layer having a relatively low elastic modulus, there are cases in which sufficient stress for cleavage due to expansion cannot be transmitted to the base layer.

The three-layered base layer 21 has two non-elastomeric layers (X, X) formed of a non-elastomer, and an elastomer layer (Y) disposed between the two non-elastomeric layers and formed of an elastomer (X Layer/Y layer/X layer) is preferable.

The elastomer layer is a layer having an elastic modulus of 200 MPa or less at room temperature. The elastomer layer is usually formed of a polymer material exhibiting rubber elasticity at room temperature (23° C.). On the other hand, the non-elastomeric layer is a layer having an elastic modulus at room temperature greater than 200 MPa.

Each layer of an elastomer having such a three-layer laminated structure is usually formed of a resin. An elastomer having a three-layer laminated structure is produced by co-extrusion molding, for example, and three layers are integrated.

In the three-layered base layer 21, the ratio of the thickness of the inner layer to the thickness of one outer layer (Y thickness/X thickness) is preferably 5 or more and 15 or less.

The non-elastomeric layer disposed on the outside has a melting point of, for example, 100°C or more and 140°C or less. Moreover, it is preferable that a non-elastomeric layer has 3 or less molecular weight distribution dispersion degree (mass average molecular weight/number average molecular weight) when GPC measurement of the resin which comprises.

The non-elastomeric layer (X) may contain low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene, or the like. Examples of the polypropylene include homopolymers (homopolypropylene) or copolymers such as random polypropylene and block polypropylene. The polypropylene may be a metallocene polypropylene synthesized by a metallocene catalyst. It is preferable that the non-elastomeric layer (X) contains metallocene polypropylene.

On the other hand, the elastomer layer (Y) preferably contains an ethylene-vinyl acetate copolymer (EVA) or an α-olefin-based thermoplastic elastomer, more preferably an ethylene-vinyl acetate copolymer (EVA). Examples of the α-olefin-based thermoplastic elastomer include a homopolymer of α-olefin and a copolymer of two or more types of α-olefin.

Ethylene-vinyl acetate copolymer resin (EVA) may contain 5 mass% or more and 35 mass% or less of structural units of vinyl acetate.

The thickness (total thickness) of the base layer 21 is 80 µm or more. Such thickness may exceed 100 µm. Such thickness may be 150 µm or less. These values are the average values of the measured values in at least three randomly selected locations. Hereinafter, also about the thickness of the pressure-sensitive adhesive layer 22, the average value is similarly adopted.

If the thickness of the base layer 21 is less than 80 µm, there is a fear that stress cannot be applied uniformly to the entire base layer 21, and thus good cleavage properties in the low-temperature expansion process may not be exhibited.

To impart releasability to the back side of the base layer 21 (the side where the adhesive layer 22 does not overlap), for example, a release treatment is performed with a release agent (release agent) such as a silicone resin or a fluorine resin. You may have it.

The base material layer 21 is preferably a light-transmitting (ultraviolet ray-transmitting) resin film or the like in that it becomes possible to provide active energy rays such as ultraviolet rays to the pressure-sensitive adhesive layer 22 from the back side.

The dicing tape 20 of the present embodiment, in a state before being used, includes a release sheet covering one side of the pressure-sensitive adhesive layer 22 (the side where the pressure-sensitive adhesive layer 22 does not overlap the base layer 21). You may have it. When the die-bonding layer 10 having an area smaller than the pressure-sensitive adhesive layer 22 is disposed so as to be accommodated in the pressure-sensitive adhesive layer 22, the release sheet covers both the pressure-sensitive adhesive layer 22 and the die-bonding layer 10. It is arranged so as to be. The release sheet is used to protect the pressure-sensitive adhesive layer 22 and is peeled off before attaching the die-bonding layer 10 to the pressure-sensitive adhesive layer 22.

As the release sheet, for example, a plastic film or paper, which has been surface-treated with a release agent such as silicone-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide, can be used.

In addition, as a release sheet, for example, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene/hexafluoropropylene copolymer, chlorofluoroethylene/vinyl fluoride Films made of fluorine-based polymers such as a leadene copolymer; Films made of polyolefins such as polyethylene and polypropylene; Polyester films, such as polyethylene terephthalate (PET), can be used.

In addition, as the release sheet, for example, a plastic film or paper, which is surface-coated with a release agent such as a fluorine-based release agent or a long-chain alkyl acrylate-based release agent, can be used.

In addition, the release sheet can be used as a support material for supporting the pressure-sensitive adhesive layer 22. In particular, the release sheet is suitably used when the pressure-sensitive adhesive layer 22 is overlaid on the base layer 21. Specifically, in a state in which the release sheet and the pressure-sensitive adhesive layer 22 are stacked, the pressure-sensitive adhesive layer 22 is overlaid on the base layer 21, and then the release sheet is peeled off (transferred). The pressure-sensitive adhesive layer 22 may be overlaid thereon.

In this embodiment, the pressure-sensitive adhesive layer 22 contains, for example, an acrylic polymer, an isocyanate compound, and a polymerization initiator.

The pressure-sensitive adhesive layer 22 preferably has a thickness of 5 µm or more and 40 µm or less. The shape and size of the pressure-sensitive adhesive layer 22 are usually the same as the shape and size of the base layer 21.

In the dicing tape 20 of the present embodiment, the ratio of the thickness of the pressure-sensitive adhesive layer 22 to the total thickness of the dicing tape 20 may be 5% or more and 30% or less.

The acrylic polymer has at least a structural unit of an alkyl (meth)acrylate, a structural unit of a hydroxyl group-containing (meth)acrylate, and a structural unit of a polymerizable group-containing (meth)acrylate in a molecule. The structural unit is a unit constituting the main chain of the acrylic polymer. Each side chain in the said acrylic polymer is contained in each structural unit which comprises a main chain.

In addition, in this specification, the notation "(meth)acrylate" represents at least one of methacrylate (methacrylic acid ester) and acrylate (acrylic acid ester). Similarly, the notation "(meth)acrylic acid" represents at least one of methacrylic acid and acrylic acid.

In the acrylic polymer contained in the pressure-sensitive adhesive layer 22, the structural unit ^{can be confirmed by NMR analysis such as 1} H-NMR and ¹³ C-NMR, thermal decomposition GC/MS analysis, and infrared spectroscopy. In addition, the molar ratio of the structural units in the acrylic polymer is usually calculated from the blending amount (input amount) when the acrylic polymer is polymerized.

The constitutional unit of the alkyl (meth) acrylate is derived from an alkyl (meth) acrylate monomer. In other words, the molecular structure after the polymerization reaction of the alkyl (meth)acrylate monomer is the structural unit of the alkyl (meth)acrylate. The notation "alkyl" represents the number of carbon atoms in the hydrocarbon portion ester bonded to (meth)acrylic acid.

The hydrocarbon moiety of the alkyl moiety in the structural unit of the alkyl (meth)acrylate may be a saturated hydrocarbon or an unsaturated hydrocarbon.

In addition, it is preferable that the alkyl moiety does not contain a polar group containing oxygen (O), nitrogen (N), or the like. Thereby, it can suppress that the polarity of an alkyl polymer becomes extremely high. Therefore, it is suppressed that the pressure-sensitive adhesive layer 22 has excessive affinity for the die-bonding layer 10. Therefore, the dicing tape 20 can be peeled more favorably from the die bonding layer 10. The number of carbon atoms in the alkyl moiety may be 6 or more and 10 or less.

As the structural unit of the alkyl (meth)acrylate, for example, each structural unit such as hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, and decyl (meth)acrylate. Can be lifted.

The acrylic polymer has a structural unit of a hydroxyl group-containing (meth)acrylate, and the hydroxyl group of such a structural unit reacts easily with an isocyanate group.

The pressure-sensitive adhesive layer 22 can be appropriately cured by coexisting the acrylic polymer having a structural unit of a hydroxyl group-containing (meth)acrylate and an isocyanate compound in the pressure-sensitive adhesive layer 22. Therefore, the acrylic polymer can be sufficiently gelled. Therefore, the adhesive layer 22 can exhibit adhesive performance while maintaining the shape.

It is preferable that the structural unit of a hydroxyl-containing (meth)acrylate is a structural unit of a hydroxyl-containing C2-C4 alkyl (meth)acrylate. The notation "C2 to C4 alkyl" represents the number of carbon atoms in the hydrocarbon portion ester bonded to (meth)acrylic acid. In other words, the hydroxyl group-containing C2 to C4 alkyl (meth)acrylate monomer represents a monomer in which (meth)acrylic acid and an alcohol having 2 to 4 carbon atoms (usually a dihydric alcohol) are ester-bonded.

The hydrocarbon moiety of C2 to C4 alkyl is usually a saturated hydrocarbon. For example, the hydrocarbon moiety of C2 to C4 alkyl is a straight chain saturated hydrocarbon or a branched chain saturated hydrocarbon. It is preferable that the hydrocarbon moiety of C2 to C4 alkyl does not contain a polar group containing oxygen (O), nitrogen (N), or the like.

As a structural unit of a hydroxyl-containing C2 to C4 alkyl (meth)acrylate, for example, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxy n-butyl (meth)acrylate, or hydroxy Each structural unit of hydroxybutyl (meth)acrylate such as oxyiso-butyl (meth)acrylate can be mentioned. In addition, in the constituent unit of hydroxybutyl (meth)acrylate, the hydroxyl group (-OH group) may be bonded to the terminal carbon (C) of the hydrocarbon moiety, or bonded to carbon (C) other than the terminal of the hydrocarbon moiety. It may be.

The acrylic polymer contains a structural unit of a polymerizable group-containing (meth)acrylate having a polymerizable unsaturated double bond in the side chain.

Since the acrylic polymer contains a structural unit of a polymerizable group-containing (meth)acrylate, the pressure-sensitive adhesive layer 22 can be cured by irradiation with active energy rays (ultraviolet rays, etc.) before the pickup step. Specifically, radicals are generated from the photopolymerization initiator by irradiation with active energy rays such as ultraviolet rays, and the acrylic polymers can be crosslinked by the action of the radicals. Thereby, the adhesive force of the pressure-sensitive adhesive layer 22 before irradiation can be reduced by irradiation. Then, the die-bonding layer 10 can be removed satisfactorily from the pressure-sensitive adhesive layer 22.

In addition, ultraviolet rays, radiation, and electron beams are employed as active energy rays.

The structural unit of the polymerizable group-containing (meth)acrylate is specifically, a molecule in which the isocyanate group of the isocyanate group-containing (meth)acrylate monomer is urethane-bonded to the hydroxyl group in the structural unit of the hydroxyl group-containing (meth)acrylate described above. You may have a structure.

The structural unit of the polymerizable group-containing (meth)acrylate having a polymerizable group can be prepared after polymerization of the acrylic polymer. For example, after copolymerization of an alkyl (meth)acrylate monomer and a hydroxyl group-containing (meth)acrylate monomer, a hydroxyl group in a part of the constituent unit of a hydroxyl group-containing (meth)acrylate and an isocyanate group-containing polymerizable monomer By urethanizing the isocyanate group, the structural unit of the polymerizable group-containing (meth)acrylate can be obtained.

It is preferable that the said isocyanate group-containing (meth)acrylate monomer has one isocyanate group in a molecule|numerator, and one (meth)acryloyl group. Examples of such a monomer include 2-(meth)acryloyloxyethyl isocyanate (2-isocyanatoethyl (meth)acrylate).

The pressure-sensitive adhesive layer 22 of the dicing tape 20 in the present embodiment further contains an isocyanate compound. Some of the isocyanate compounds may be in a state after reacting by a urethanization reaction or the like.

The isocyanate compound has a plurality of isocyanate groups in the molecule. When the isocyanate compound has a plurality of isocyanate groups in the molecule, the crosslinking reaction between the acrylic polymers in the pressure-sensitive adhesive layer 22 can be advanced. Specifically, one isocyanate group among the isocyanate compounds is reacted with a hydroxyl group of an acrylic polymer, and the other isocyanate group is reacted with a hydroxyl group of another acrylic polymer, whereby the crosslinking reaction through the isocyanate compound can be promoted.

As an isocyanate compound, diisocyanate, such as an aliphatic diisocyanate, an alicyclic diisocyanate, or an aromatic aliphatic diisocyanate, is mentioned, for example.

Further, examples of the isocyanate compound include polymerized polyisocyanates such as dimers and trimers of diisocyanates, and polymethylene polyphenylene polyisocyanates.

Moreover, as an isocyanate compound, the polyisocyanate which made the excess amount of the above-mentioned isocyanate compound and an active hydrogen-containing compound react is mentioned, for example. Examples of the active hydrogen-containing compound include active hydrogen-containing low molecular weight compounds and active hydrogen-containing high molecular weight compounds.

Moreover, as an isocyanate compound, allophanated polyisocyanate, biuret-type polyisocyanate, etc. can also be used.

These isocyanate compounds may be used alone or in combination of two or more.

As the isocyanate compound, a reaction product of an aromatic diisocyanate and an active hydrogen-containing low molecular weight compound is preferable. Since the reaction rate of the reaction product of the aromatic diisocyanate group is relatively slow, the pressure-sensitive adhesive layer 22 containing such a reaction product is suppressed from being excessively cured. As said isocyanate compound, it is preferable to have 3 or more isocyanate groups in a molecule|numerator.

The polymerization initiator contained in the pressure-sensitive adhesive layer 22 is a compound capable of initiating a polymerization reaction by applied heat or energy of light. When the pressure-sensitive adhesive layer 22 contains a polymerization initiator, when heat energy or light energy is applied to the pressure-sensitive adhesive layer 22, the crosslinking reaction between the acrylic polymers can be advanced. Specifically, between acrylic polymers having a structural unit of a polymerizable group-containing (meth)acrylate, a polymerization reaction between polymerizable groups can be initiated, and the pressure-sensitive adhesive layer 22 can be cured. Thereby, the adhesive force of the pressure-sensitive adhesive layer 22 is lowered, and the die-bonding layer 10 can be easily peeled off from the cured pressure-sensitive adhesive layer 22 in the pick-up step.

As a polymerization initiator, a photoinitiator, a thermal polymerization initiator, etc. are adopted, for example. As the polymerization initiator, general commercial products can be used.

The pressure-sensitive adhesive layer 22 may further contain other components other than the above-described components. Examples of other components include tackifiers, plasticizers, fillers, anti-aging agents, antioxidants, ultraviolet absorbers, light stabilizers, heat-resistant stabilizers, antistatic agents, surfactants, and light peeling agents. The type and amount of other ingredients may be appropriately selected depending on the purpose.

Next, the dicing die-bonding film 1 of the present embodiment will be described in detail.

The dicing die-bonding film 1 of the present embodiment includes the above-described dicing tape 20 and the die-bonding layer 10 laminated on the pressure-sensitive adhesive layer 22 of the dicing tape 20. The die bonding layer 10 is adhered to a semiconductor wafer in manufacturing a semiconductor integrated circuit.

The die bonding layer 10 may contain at least one of a thermosetting resin and a thermoplastic resin. It is preferable that the die bonding layer 10 contains a thermosetting resin and a thermoplastic resin.

As a thermosetting resin, an epoxy resin, a phenol resin, an amino resin, an unsaturated polyester resin, a polyurethane resin, a silicone resin, a thermosetting polyimide resin, etc. are mentioned, for example. As the thermosetting resin, only one type or two or more types are employed. Epoxy resin is preferable as the thermosetting resin from the viewpoint of containing less ionic impurities or the like that may cause corrosion of the semiconductor chip to be die-bonded. As a curing agent for an epoxy resin, a phenol resin is preferable.

Examples of the epoxy resin include bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolak type , Orthocresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, hydantoin type, trisglycidyl isocyanurate type, or glycidylamine type epoxy resin.

The phenol resin can function as a curing agent for an epoxy resin. As a phenol resin, polyoxystyrene, such as a novolak type phenol resin, a resol type phenol resin, and polyparaoxy styrene, etc. are mentioned, for example.

As a novolak type phenol resin, a phenol novolak resin, a phenol aralkyl resin, a cresol novolak resin, a tert-butylphenol novolak resin, a nonylphenol novolak resin, etc. are mentioned, for example.

As the phenol resin, only one type or two or more types are employed.

In the die-bonding layer 10, the hydroxyl group of the phenol resin is per 1 equivalent of the epoxy group of the epoxy resin, preferably 0.5 equivalents or more and 2.0 equivalents or less, and more preferably 0.7 equivalents or more and 1.5 equivalents or less. Thereby, it is possible to sufficiently advance the curing reaction of the epoxy resin and the phenol resin.

When the die bonding layer 10 contains a thermosetting resin, the content ratio of the thermosetting resin in the die bonding layer 10 is 5% by mass or more and 60% by mass with respect to the total mass of the die bonding layer 10. The following are preferable, and 10 mass% or more and 50 mass% or less are more preferable. Thereby, in the die-bonding layer 10, the function as a thermosetting adhesive can be appropriately expressed.

As a thermoplastic resin that can be included in the die bonding layer 10, for example, natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, poly Butadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resin such as 6-nylon or 6,6-nylon (brand name), phenoxy resin, acrylic resin, saturated polyester resin such as PET or PBT, poly An amidimide resin, a fluororesin, and the like.

As the thermoplastic resin, since there are few ionic impurities and high heat resistance, the adhesiveness of the die-bonding layer 10 can be more secured, and an acrylic resin is preferable.

As the thermoplastic resin, only one type or two or more types are employed.

It is preferable that the said acrylic resin is a polymer in which the structural unit of an alkyl (meth)acrylate is the largest among structural units in a molecule|numerator by mass ratio. Examples of the alkyl (meth)acrylate include C2 to C4 alkyl (meth)acrylate.

The acrylic resin may contain a structural unit derived from another monomer component copolymerizable with an alkyl (meth)acrylate monomer.

Examples of the other monomer components include a carboxyl group-containing monomer, an acid anhydride monomer, a hydroxy group-containing monomer, a glycidyl group-containing monomer, a sulfonic acid group-containing monomer, a phosphate group-containing monomer, an acrylamide, an acrylonitrile, or other functional group-containing monomer, or a monomer thereof. In addition, various polyfunctional monomers, etc. can be mentioned.

The acrylic resin is preferably an alkyl (meth)acrylate (particularly, an alkyl (meth)acrylate having 4 or less carbon atoms in the alkyl moiety) from the viewpoint of being able to exhibit a higher cohesive force in the die-bonding layer 10. And, a carboxy group-containing monomer, a nitrogen atom-containing monomer, and a polyfunctional monomer (especially a polyglycidyl polyfunctional monomer), and more preferably ethyl acrylate, butyl acrylate, acrylic acid, and acrylonitrile. And, it is a copolymer of polyglycidyl (meth)acrylate.

The glass transition temperature (Tg) of the acrylic resin is preferably -50°C or more and 50°C or less, and 10°C or more and 30°C or less from the viewpoint of being easy to set the elasticity and viscosity of the die-bonding layer 10 within a desired range. It is more preferable.

When the die-bonding layer 10 contains a thermosetting resin and a thermoplastic resin, the content ratio of the thermoplastic resin in the die-bonding layer 10 is an organic component excluding a filler (for example, a thermosetting resin, a thermoplastic resin, With respect to the total mass of a silane coupling agent, dye), such as a curing catalyst, Preferably it is 30 mass% or more and 70 mass% or less, More preferably, it is 40 mass% or more and 60 mass% or less, More preferably 45 mass% It is more than 55 mass %. Further, by changing the content ratio of the thermosetting resin, the elasticity and viscosity of the die-bonding layer 10 can be adjusted.

When the thermoplastic resin of the die bonding layer 10 has a thermosetting functional group, as the thermoplastic resin, for example, an acrylic resin containing a thermosetting functional group can be employed. This thermosetting functional group-containing acrylic resin preferably contains a structural unit derived from an alkyl (meth)acrylate in the molecule in the largest mass ratio. As said alkyl (meth)acrylate, the (meth)alkyl (meth)acrylate of the said example is mentioned, for example.

On the other hand, as a thermosetting functional group in a thermosetting functional group-containing acrylic resin, a glycidyl group, a carboxyl group, a hydroxy group, an isocyanate group, etc. are mentioned, for example.

It is preferable that the die-bonding layer 10 contains a thermosetting functional group-containing acrylic resin and a curing agent. When the thermosetting functional group in the thermosetting functional group-containing acrylic resin is a glycidyl group, it is preferable to use a compound having a plurality of phenol structures as a curing agent. For example, various phenolic resins described above can be used as a curing agent.

The die bonding layer 10 preferably contains a filler. By changing the amount of the filler in the die-bonding layer 10, the elasticity and viscosity of the die-bonding layer 10 can be more easily adjusted. In addition, physical properties such as conductivity, thermal conductivity, and elastic modulus of the die-bonding layer 10 can be adjusted.

Examples of the filler include inorganic fillers and organic fillers. As a filler, an inorganic filler is preferable.

Examples of the inorganic filler include silica such as aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, boron nitride, crystalline silica or amorphous silica. The filler to contain is mentioned. Further, examples of the material of the inorganic filler include metals such as aluminum, gold, silver, copper, and nickel, or alloys. A filler, such as aluminum borate whisker, amorphous carbon black, and graphite, may be sufficient. The shape of the filler may be various shapes such as a spherical shape, a needle shape, and a flake shape. As a filler, only the said 1 type or 2 or more types are adopted.

The average particle diameter of the filler is preferably 0.005 µm or more and 10 µm or less, and more preferably 0.005 µm or more and 1 µm or less. When the average particle diameter is 0.005 µm or more, wettability and adhesion to an adherend such as a semiconductor wafer are further improved. When the average particle diameter is 10 µm or less, the properties due to the added filler can be more fully exhibited, and the heat resistance of the die-bonding layer 10 can be further exhibited. The average particle diameter of the filler can be obtained using, for example, a photometric particle size distribution meter (for example, the product name "LA-910", manufactured by Horiba Seisakusho Co., Ltd.).

When the die-bonding layer 10 contains a filler, the content ratio of the filler is preferably 30% by mass or more and 70% by mass or less, and more preferably 40% by mass, based on the total mass of the die-bonding layer 10. It is mass% or more and 60 mass% or less, More preferably, it is 42 mass% or more and 55 mass% or less.

The die-bonding layer 10 may contain other components as necessary. Examples of the other components include a curing catalyst, a flame retardant, a silane coupling agent, an ion trapping agent, and a dye.

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

Examples of the silane coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane. have.

Examples of the ion trapping agent include hydrotalcite, bismuth hydroxide, and benzotriazole.

As said other additive, only 1 type or 2 or more types are employed.

The die-bonding layer 10 preferably contains a thermoplastic resin (particularly, an acrylic resin), a thermosetting resin, and a filler from the viewpoint of being easy to adjust the elasticity and viscosity.

The thickness of the die-bonding layer 10 is not particularly limited, but is, for example, 1 µm or more and 200 µm or less. Such thickness may be 3 µm or more and 150 µm or less, or 5 µm or more and 100 µm or less. In addition, when the die-bonding layer 10 is a laminated body, the thickness is the total thickness of the laminated body.

The glass transition temperature (Tg) of the die bonding layer 10 is preferably 0°C or higher, and more preferably 10°C or higher. When the glass transition temperature is 0° C. or higher, the die bond layer 10 can be easily cleaved by low-temperature expansion. The upper limit of the glass transition temperature of the die bonding layer 10 is, for example, 100°C.

The die-bonding layer 10 may have a single-layer structure, for example, as shown in FIG. 1. In this specification, a single layer has only a layer formed of the same composition. The form in which multiple layers formed of the same composition are stacked is also a single layer.

On the other hand, the die-bonding layer 10 may have a multilayer structure in which layers each formed of two or more different compositions are stacked, for example.

In the dicing die-bonding film 1 of the present embodiment, when used, the pressure-sensitive adhesive layer 22 is cured by being irradiated with an active energy ray (for example, ultraviolet rays). Specifically, in a state in which the die bond layer 10 to which the semiconductor wafer is adhered to one side and the pressure-sensitive adhesive layer 22 bonded to the other side of the die bond layer 10 are stacked, ultraviolet rays or the like are at least a pressure-sensitive adhesive. The layer 22 is irradiated. For example, an ultraviolet ray or the like is irradiated from the side on which the base layer 21 is disposed, and the ultraviolet ray or the like that has passed through the base layer 21 reaches the pressure-sensitive adhesive layer 22. The pressure-sensitive adhesive layer 22 is cured by irradiation such as ultraviolet rays.

Since the adhesive strength of the pressure-sensitive adhesive layer 22 can be lowered by curing the pressure-sensitive adhesive layer 22 after irradiation, the die-bonding layer 10 (a state in which the semiconductor wafer is adhered) is relatively easily peeled from the pressure-sensitive adhesive layer 22 after irradiation. I can make it.

In the state before use, the dicing die-bonding film 1 of the present embodiment has one surface of the die-bonding layer 10 (the surface in which the die-bonding layer 10 does not overlap the pressure-sensitive adhesive layer 22). You may provide a covering release sheet. The release sheet is used to protect the die-bonding layer 10 and is peeled immediately before affixing an adherend (for example, a semiconductor wafer) to the die-bonding layer 10.

As this release sheet, the same thing as the release sheet mentioned above can be adopted. This release sheet can be used as a support material for supporting the die bonding layer 10. The release sheet is suitably used when overlapping the die-bonding layer 10 on the pressure-sensitive adhesive layer 22. Specifically, by overlapping the die-bonding layer 10 on the pressure-sensitive adhesive layer 22 in a state in which the release sheet and the die-bonding layer 10 are stacked, and then peeling the release sheet (transferring), the pressure-sensitive adhesive layer 22 ) On top of the die bond layer 10 may be overlapped.

Since the dicing die-bonding film 1 of the present embodiment is configured as described above, the semiconductor wafer can be satisfactorily cut in the low-temperature expansion step described later.

Next, a method of manufacturing the dicing tape 20 and the dicing die-bonding film 1 of the present embodiment will be described.

The manufacturing method of the dicing die-bonding film 1 of this embodiment,

The process of manufacturing the dicing tape 20 (the manufacturing method of the dicing tape) and the process of manufacturing the dicing die-bonding film 1 by overlapping the die-bonding layer 10 on the manufactured dicing tape 20 are described. Equipped.

The manufacturing method (process of manufacturing a dicing tape) of a dicing tape,

Synthesis process of synthesizing acrylic polymer,

A pressure-sensitive adhesive layer production step of producing the pressure-sensitive adhesive layer 22 by volatilizing a solvent from the pressure-sensitive adhesive composition containing the above-described acrylic polymer, an isocyanate compound, a polymerization initiator, a solvent, and other components appropriately added depending on the purpose;

The base layer manufacturing process of manufacturing the base layer 21, and

A lamination step of laminating the substrate layer 21 and the pressure-sensitive adhesive layer 22 is provided by bonding the pressure-sensitive adhesive layer 22 and the substrate layer 21.

In the synthesis step, an acrylic polymer intermediate is synthesized by radical polymerization of, for example, a C9 to C11 alkyl (meth)acrylate monomer and a hydroxyl group-containing (meth)acrylate monomer.

Radical polymerization can be performed by a general method. For example, an acrylic polymer intermediate can be synthesized by dissolving each of the above monomers in a solvent, stirring while heating, and adding a polymerization initiator. In order to adjust the molecular weight of the acrylic polymer, polymerization may be performed in the presence of a chain transfer agent.

Next, the hydroxyl group of a part of the structural unit of the hydroxyl group-containing (meth)acrylate contained in the acrylic polymer intermediate and the isocyanate group of the isocyanate group-containing polymerizable monomer are bonded to each other by a urethanization reaction. Thereby, some of the structural units of the hydroxyl group-containing (meth)acrylate become the structural units of the polymerizable group-containing (meth)acrylate.

The urethanization reaction can be performed by a general method. For example, in the presence of a solvent and a urethanization catalyst, the acrylic polymer intermediate and the isocyanate group-containing polymerizable monomer are stirred while heating. Thereby, the isocyanate group of the isocyanate group-containing polymerizable monomer can be urethane bonded to a part of the hydroxyl groups of the acrylic polymer intermediate.

In the pressure-sensitive adhesive layer production process, for example, an acrylic polymer, an isocyanate compound, and a polymerization initiator are dissolved in a solvent to prepare a pressure-sensitive adhesive composition. By varying the amount of solvent, the viscosity of the composition can be adjusted. Next, the pressure-sensitive adhesive composition is applied to the release sheet. As the coating method, for example, a general coating method such as roll coating, screen coating, and gravure coating is adopted. By subjecting the applied composition to a solvent removal treatment, a solidification treatment, or the like, the applied pressure-sensitive adhesive composition is solidified, and the pressure-sensitive adhesive layer 22 is produced.

In the base material layer production process, the base material layer 21 can be produced by forming a film by a general method. As a method of forming a film, a calender film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T-die extrusion method, a dry lamination method, and the like can be mentioned. You may adopt a co-extrusion molding method. Further, as the substrate layer 21, a commercially available film or the like may be used.

In the lamination process, the pressure-sensitive adhesive layer 22 and the substrate layer 21 in a state of being superposed on the release sheet are stacked and laminated. Further, the release sheet may be in a state of being overlaid on the pressure-sensitive adhesive layer 22 before use.

In addition, in order to accelerate the reaction between the crosslinking agent and the acrylic polymer, and in order to accelerate the reaction between the crosslinking agent and the surface portion of the substrate layer 21, after the lamination process, an aging treatment process of 48 hours in an environment at 50°C may be performed do.

By these processes, the dicing tape 20 can be manufactured.

The manufacturing method of a dicing die-bonding film (process of manufacturing a dicing die-bonding film),

A resin composition preparation step of preparing a resin composition for forming the die-bonding layer 10, and

A die-bonding layer production process of producing the die-bonding layer 10 from a resin composition, and

An attaching step of attaching the die bonding layer 10 to the pressure-sensitive adhesive layer 22 of the dicing tape 20 prepared as described above is provided.

In the resin composition preparation step, for example, an epoxy resin, a curing catalyst for an epoxy resin, an acrylic resin, a phenol resin, a solvent, and the like are mixed and each resin is dissolved in a solvent to prepare a resin composition. By varying the amount of solvent, the viscosity of the composition can be adjusted. In addition, as these resins, commercially available products can be used.

In the die-bonding layer production process, for example, the resin composition prepared as described above is applied to the release sheet. It does not specifically limit as a coating method, For example, general coating methods, such as roll coating construction, screen coating construction, and gravure coating construction, are adopted. Subsequently, if necessary, the applied composition is solidified by a solvent removal treatment, a curing treatment, or the like, and the die-bonding layer 10 is produced.

In the affixing process, the peeling sheets are peeled from the pressure-sensitive adhesive layer 22 and the die-bonding layer 10 of the dicing tape 20, respectively, so that the die-bonding layer 10 and the pressure-sensitive adhesive layer 22 are in direct contact with each other. Join. For example, it can be bonded by pressing. The temperature at the time of bonding is not particularly limited, and is, for example, 30°C or more and 50°C or less, and preferably 35°C or more and 45°C or less. The line pressure at the time of bonding is not particularly limited, but is preferably 0.1 kgf/cm or more and 20 kgf/cm or less, and more preferably 1 kgf/cm or more and 10 kgf/cm or less.

The dicing die-bonding film 1 manufactured as described above is used, for example, as an auxiliary tool for manufacturing a semiconductor integrated circuit. Hereinafter, specific examples in use will be described.

A method of manufacturing a semiconductor integrated circuit generally includes a step of cutting out a chip from a semiconductor wafer on which a circuit surface is formed and performing assembly.

This process includes, for example, a half-cut process in which a groove is formed in a semiconductor wafer to process a semiconductor wafer into a chip (die) by a cutting process, and the semiconductor wafer is ground to reduce the thickness, and a half-cut processed semiconductor. A mounting process of attaching one side of the wafer (e.g., the side opposite to the circuit side) to the die bonding layer 10 and fixing the semiconductor wafer to the dicing tape 20, and the half-cut semiconductor chips A pick-up process in which a semiconductor chip (die) is taken out while the die-bonding layer 10 is affixed by peeling the gap between the die-bonding layer 10 and the pressure-sensitive adhesive layer 22, and the die It has a die bonding process of adhering the semiconductor chip (die) in the state where the bonding layer 10 is affixed to the adherend. When performing these processes, the dicing tape (dicing die-bonding film) of this embodiment is used as a manufacturing auxiliary tool.

In the half-cut process, as shown in Figs. 2A to 2D, half-cut processing is performed to cut the semiconductor integrated circuit into small pieces (die). Specifically, the wafer processing tape T is affixed on the surface of the semiconductor wafer W on the opposite side to the circuit surface. Further, a dicing ring R is provided on the wafer processing tape T. In the state where the wafer processing tape T is affixed, a dividing groove is formed. While the backgrind tape G is affixed to the grooved surface, the wafer processing tape T that was first affixed is peeled off. Grinding is performed until the semiconductor wafer W has a predetermined thickness while the backgrinding tape G is affixed thereto.

In the mounting process, as shown in Figs. 3A to 3B, while installing a dicing ring R on the pressure-sensitive adhesive layer 22 of the dicing tape 20, the surface of the exposed die-bonding layer 10 is half-cut. The processed semiconductor wafer W is affixed. After that, the backgrind tape G is peeled from the semiconductor wafer W.

In the expanding process, as shown in Figs. 4A to 4C, after the dicing ring R is provided on the pressure-sensitive adhesive layer 22 of the dicing tape 20, it is fixed to the holder H of the expander. The dicing die-bonding film 1 is stretched so as to widen in the direction by pushing up the push-up member U provided in the expander from the lower side of the dicing die-bonding film 1. Thereby, under a specific temperature condition, the semiconductor wafer W processed by half cut is cut|disconnected. The temperature conditions are, for example, -20 to 0°C, preferably -15 to 0°C, and more preferably -10 to -5°C. The expanded state is canceled by lowering the push-up member U (low temperature expand process up to this point). Further, in the expand process, as shown in Figs. 5A to 5B, the dicing tape 20 is stretched to increase the area under a higher temperature condition. Thereby, the divided adjacent semiconductor chips are separated in the plane direction of the film surface, and the cuff (interval) is further widened (room temperature expansion process).

In the pick-up process, as shown in FIG. 6, the semiconductor chip in a state in which the die bonding layer 10 is affixed is peeled from the pressure-sensitive adhesive layer 22 of the dicing tape 20. Specifically, the pin member P is raised, and the semiconductor chip to be picked up is pushed up through the dicing tape 20. The pushed-up semiconductor chip is held by the suction jig J.

In the die bonding process, the semiconductor chip in a state in which the die bonding layer 10 is affixed is bonded to the adherend.

As described above, the dicing die-bonding film 1 (dicing tape 20) of the present embodiment is used in the above process, and in the low-temperature expanding process, at 0°C or less, the die-bonding layer 10 In a state in which the wafer is adhered to, the dicing tape 20 is stretched, and the wafer is cut together with the die bonding layer 10. Further, in the expanding process at room temperature, the dicing tape 20 is stretched.

In addition, the temperature in the low-temperature expansion process is usually 0°C or less, for example, -15°C to 0°C. The temperature in the expand process at room temperature is, for example, a temperature of 10°C to 25°C.

Matters disclosed by this specification include the following.

(One)

A substrate layer and a pressure-sensitive adhesive layer having higher adhesion than the substrate layer are provided,

The dicing tape, wherein the volume crystallinity calculated from the differential scanning calorimetry result of the base layer is 20 J/cm 3 or more and 120 J/cm 3 or less, and the base layer has a thickness of 80 μm or more.

(2)

The dicing tape according to (1), wherein the chart obtained by measuring the base material layer by differential scanning calorimetry has an endothermic peak, and the peak temperature of the endothermic peak is 100°C or higher.

(3)

The dicing tape according to (2), wherein the temperature difference between the peak start point (point A) and the peak (point C) in the endothermic peak is 40°C or less.

(4)

The dicing tape according to (2) or (3), wherein the temperature difference between the peak start point (point A) and the peak end point (point B) is 30°C or more and 60°C or less in the endothermic peak.

(5)

The dicing tape according to any one of the above (2) to (4), wherein the temperature at the peak initiation point (point A) is 70°C or higher in the endothermic peak.

(6)

The dicing tape according to any one of the above (2) to (5), wherein the temperature at the peak end point (point B) is 150°C or less in the endothermic peak.

(7)

The dicing tape according to any one of (1) to (6), wherein the base layer has a single-layer structure or a laminated structure.

(8)

The dicing tape according to any one of (1) to (7), wherein the base material layer is composed of at least three layers.

(9)

The base layer has a three-layer structure, two non-elastomeric layers (X, X) formed of a non-elastomer, and an elastomer layer (Y) disposed between the two non-elastomeric layers and formed of an elastomer. The dicing tape described in (8).

(10)

The dicing tape according to (9), wherein the base layer has a three-layer structure, and the ratio of the thickness of the inner layer to the thickness of one outer layer (Y thickness/X thickness) is 5 or more and 15 or less.

(11)

The dicing tape according to (9) or (10), wherein the non-elastomeric layer (X) contains at least one selected from the group consisting of low-density polyethylene (LDPE), high-density polyethylene (HDPE), and polypropylene.

(12)

The dicing tape according to any one of (9) to (11), wherein the elastomer layer (Y) contains an ethylene-vinyl acetate copolymer (EVA).

(13)

The dicing tape according to any one of (1) to (11), wherein the ratio of the thickness of the pressure-sensitive adhesive layer to the total thickness of the dicing tape is 5% or more and 30% or less.

(14)

A dicing die-bonding film comprising the dicing tape according to any one of the above (1) to (13) and a die-bonding layer bonded to the dicing tape.

(15)

The dicing die-bonding film according to (14), wherein the die-bonding layer contains at least one of a thermosetting resin and a thermoplastic resin.

(16)

The dicing die-bonding film according to (14) or (15), wherein the die-bonding layer has a thickness of 1 µm or more and 200 µm or less.

The dicing tape and dicing die-bonding film of this embodiment are as exemplified above, but the present invention is not limited to the dicing tape and dicing die-bonding film exemplified above.

That is, various forms used in general dicing tapes and dicing die-bonding films can be employed within a range that does not impair the effects of the present invention.

Example

Next, the present invention will be described in more detail by experimental examples, but the present invention is not limited thereto.

It carried out as follows, and the dicing tape was manufactured. Further, this dicing tape was used to prepare a dicing die-bonding film.

<Base layer>

Using the product shown below as a raw material, a three-layered substrate layer or a single-layered substrate layer was produced.

·Resin constituting the inner layer

Raw material name: Ultrasen 626

Ethylene-vinyl acetate copolymer resin (contains 15% by mass of EVA vinyl acetate)

Toso Priest

·Resin constituting the inner layer

Raw material name: Ultrasen 633

Ethylene-vinyl acetate copolymer resin (contains 20% by mass of EVA vinyl acetate)

Toso Priest

·Resin constituting the inner layer

Raw material name: Evaflex V523

Ethylene-vinyl acetate copolymer resin (contains 33% by mass of EVA vinyl acetate)

Mitsui Dow Polychemical Co., Ltd.

·Resin constituting the inner layer

Raw material name: Evaflex P1007

Ethylene-vinyl acetate copolymer resin (contains 9% by mass of EVA vinyl acetate)

Mitsui Dow Polychemical Co., Ltd.

Resin constituting the base layer of the comparative example

Raw material name: Infuse9530

α-olefin block copolymer resin

Dow Chemical Co., Ltd.

·Resin constituting the outer layer

Raw material name: WINTEC WFX4M

Metallocene polypropylene

Made by Polypro, Japan

(Molding of the base layer)

The base layer was molded using an extrusion T-die molding machine. The extrusion temperature was 190°C. The three-layer laminated-type substrate layer was integrated by coextrusion molding from a T-die. After the integrated base layer (laminate) was sufficiently solidified, the base layer was wound up in a roll shape and stored.

In addition, the thickness ratio of each layer constituting the base layer and the total thickness of the base layer are as shown in Table 1.

<Adhesive layer>

(Preparation of an adhesive layer (adhesive composition))

The following raw materials were mixed to prepare a first resin composition.

INA (isononyl acrylate) 173 parts by mass

-HEA (hydroxyethyl acrylate) 54.5 parts by mass

AIBN (2,2'-azobisisobutyronitrile) 0.46 parts by mass

・372 parts by mass of ethyl acetate

Next, the first resin composition was placed in a round bottom separable flask of a polymerization experimental apparatus equipped with a round bottom separable flask (volume 1 L), a thermometer, a nitrogen introduction tube, and a stirring blade. While stirring the first resin composition, the inside of the round-bottom separable flask was replaced with nitrogen gas for 6 hours while adjusting the liquid temperature of the first resin composition to room temperature (23°C).

Subsequently, while stirring the first resin composition while flowing nitrogen gas into the round bottom separable flask, the liquid temperature of the first resin composition was maintained at 62°C for 3 hours. Then, by further holding|maintenance at 75 degreeC for 2 hours, the polymerization reaction of the said INA, HEA, and AIBN was performed, and the 2nd resin composition was prepared. After that, the introduction of nitrogen gas into the round bottom separable flask was stopped.

After cooling the second resin composition until it reached room temperature, the following raw materials were added to the second resin composition.

2-methacryloyloxyethyl isocyanate

Compounds with polymerizable carbon-carbon double bonds

Brand name "Carens MOI", manufactured by Showa Denko) 52.5 parts by mass

-Dibutyltin dilaurate IV (made by Wako Junyaku Kogyo) 0.26 parts by mass

The obtained 3rd resin composition was stirred at 50 degreeC in an air atmosphere for 24 hours.

Finally, the following raw materials were added to 100 parts by mass of the polymer solid content of the third resin composition.

・Isocyanate compound (brand name "Coronate L", manufactured by Tosoh Corporation) 0.75 parts by mass

Photoinitiator (trade name "Omnirad 127", manufactured by IGM Resins) 2 parts by mass

And the 3rd resin composition was diluted with ethyl acetate so that the solid content concentration might become 20 mass %, and the adhesive composition was prepared.

<Manufacture of dicing tape>

A pressure-sensitive adhesive composition was applied to one surface of the base layer using an applicator so that the thickness after drying was 10 µm. The substrate layer after application of the pressure-sensitive adhesive composition was heated and dried at 110° C. for 3 minutes to form a pressure-sensitive adhesive layer to prepare a dicing tape.

<Production of dicing die-bonding film>

(Production of die bond layer)

The following raw materials were added to methyl ethyl ketone and mixed to obtain a composition for a die-bonding layer having a solid content concentration of 20% by mass.

100 parts by mass of acrylic resin (brand name "SG-P3", manufactured by Nagase Chemtex, glass transition temperature of 12°C)

Epoxy resin (brand name "JER1001", manufactured by Mitsubishi Chemical) 46 parts by mass

-Phenol resin (trade name "MEH-7851ss", manufactured by Meiwa Kasei) 51 parts by mass

・Spherical silica (brand name "SO-25R", manufactured by Admatex) 191 parts by mass

-Curing catalyst (trade name "Curesol PHZ", manufactured by Shikoku Kasei Kogyo Co., Ltd.) 0.6 parts by mass

Next, a release liner was prepared in which a PET separator (thickness 50 µm) was subjected to silicone treatment. The composition for a die-bonding layer was applied by an applicator to a thickness of 10 µm after drying on the treated surface of this release liner. The solvent was volatilized from the die-bonding layer composition by drying treatment at 130° C. for 2 minutes to obtain a die-bonding sheet in which a die-bonding layer was laminated on a release liner.

(Joining die bond layer and dicing tape)

Subsequently, the pressure-sensitive adhesive layer of the dicing tape and the die-bonding layer in the die-bonding sheet (the side on which the peeling sheet was not laminated) were bonded. Then, the release liner was peeled off from the die bonding layer, and a dicing die bonding film provided with the die bonding layer was produced.

As described above, according to the above method, the dicing tapes and dicing die-bonding films of Examples and Comparative Examples were manufactured, respectively. Table 1 shows the configuration of each dicing tape.

The method of calculating the volume crystallinity is as follows. The amount of heat absorbed by the inner layer was multiplied by the ratio of the thickness occupied by the inner layer, and then the specific gravity of the inner layer was multiplied to calculate the volume crystallinity of the inner layer. Similarly, the volume crystallinity was calculated also for the outer layer. And these calculated values were summed. The total value was adopted as the volume crystallinity.

<Measurement of differential scanning calorimetry (DSC)>

A sample for measurement was taken out from the dicing tapes of each Example and each Comparative Example. The measurement sample was taken out from the substrate layer by cutting the substrate layer in the thickness direction.

Using a commercially available DSC measuring device, about 10 mg of the sample for measurement was weighed, and measurement was performed in a nitrogen gas atmosphere from room temperature (about 20°C) to 200°C at a temperature increase rate of 5°C/min.

The area of the endothermic peak shown in the measurement chart, the peak start point of the endothermic peak, the peak peak, and the respective temperatures of the peak end point were measured by the analysis software attached to the apparatus.

When a plurality of peaks appeared in the measurement chart, each of the above temperatures and the like were measured for each peak.

The details of the DSC measurement device and analysis software are as follows.

Measuring device: T-A, Instrument, Japan Co., Ltd. product

Device name DSC Q-2000

Analysis software: TA Instruments Universal Analysis 2000 version 4.5A

Charts when differential scanning calorimetry (DSC measurement) was performed on the base layer of Example 1 are shown in Figs. 7A and 7B. 7A and 7B show the same measurement results in different display formats, respectively. In Fig. 7A, the inclined line in the chart represents the temperature.

Similarly, charts when differential scanning calorimetry (DSC measurement) was performed on the base layer of Comparative Example 1 are shown in Figs. 8A and 8B.

<Performance evaluation (evaluation of splitting property)>

Performance evaluation was performed as follows using the dicing die-bonding film produced in each Example and each comparative example.

After affixing a wafer processing tape (brand name "V-12SR2", manufactured by Nitto Denko Co., Ltd.) on one side of a bare wafer (diameter 300 mm), the bare wafer is fixed to a dicing ring through a wafer processing tape, and diced. Using an apparatus (manufactured by DISCO, Model No. 6361), from the side opposite to the side to which the wafer processing tape was attached, a grid-shaped groove (25 µm width, 100 µm depth) so that the chip becomes a 2 mm x 2 mm square. Formed. Next, the wafer processing tape (trade name "V-12SR2", manufactured by Nitto Denko Corporation) was peeled off from the wafer, and the backgrind tape was bonded to the grooved surface, and a back grinder (manufactured by DISCO, Model DGP8760) was applied. By using, the bare wafer was ground so that the thickness became 30 micrometers (0.030 mm).

On the die-bonding film side of the dicing die-bonding tape, a ground wafer with a backgrind tape was bonded at a temperature of 60°C. Next, the dicing die-bonding film bonded to the wafer after grinding was bonded to the ring and fixed, and then the backgrind tape was peeled off. Thereafter, with a cool expander unit, the die bonding layer was cut off under the conditions of an expand temperature of -5°C, an expand speed of 100 mm/sec, and an expand amount of 14 mm. Next, room temperature expansion was performed under the conditions of room temperature, an expand speed of 1 mm/sec, and an expand amount of 10 mm. Then, while maintaining the expanded state, the outer peripheral portion of the dicing die-bonding film was heat-shrunk under conditions of a heat temperature of 200°C, a heat distance of 18 mm, and a rotation speed of 5°/sec.

In the dicing die-bonding film after heat shrinkage, the cutting of the die-bonding layer was confirmed under a microscope, and the case where the cleaving ratio was 90% or more was set to △, the case of less than 90% to 80% or more was set to △, and the case of less than 80% was set to ×.

Table 1 shows the results of performing differential scanning calorimetry (DSC) measurement and performance evaluation (evaluation of splitting properties) with respect to the base layer of the dicing tapes of each of Examples and Comparative Examples.

As understood from the above evaluation results, the dicing die-bonding film of the example was able to cut the semiconductor wafer favorably in the low-temperature expansion process compared to the dicing die-bonding film of the comparative example.

In the dicing tape of Examples, the volume crystallinity calculated from the DSC measurement chart of the base layer is 20 J/cm 3 or more and 120 J/cm 3 or less, and the thickness of the base layer is 80 μm or more.

Since the volume crystallinity is 20 J/cm 3 or more, the crystallinity in the base layer is relatively large, and the semiconductor wafer can be cut favorably in the low-temperature expansion process. In addition, since the volume crystallinity is 120 J/cm 3 or less, the crystallinity in the base layer is not as large as necessary, and rupture of the base layer 21 at the time of expansion is suppressed.

By using the dicing tape (dicing die-bonding film) of the embodiment provided with a substrate layer having such physical properties in the manufacture of a semiconductor integrated circuit, rupture of the substrate layer 21 is suppressed while in a low-temperature expansion process. The semiconductor wafer can be cut favorably.

The dicing tape and dicing die-bonding film of the present invention are suitably used, for example, as auxiliary tools when manufacturing a semiconductor integrated circuit.

1: dicing die bond film
10: die bond layer
20: dicing tape
21: base layer
22: adhesive layer

Claims (3)

A substrate layer and a pressure-sensitive adhesive layer having higher adhesion than the substrate layer are provided,
The dicing tape, wherein the volume crystallinity calculated from the differential scanning calorimetry result of the base layer is 20 J/cm 3 or more and 120 J/cm 3 or less, and the base layer has a thickness of 80 µm or more. The method of claim 1,
The chart obtained by measuring the base material layer by differential scanning calorimetry has an endothermic peak and a peak temperature of the endothermic peak is 100°C or higher. A dicing die-bonding film comprising the dicing tape according to claim 1 or 2, and a die-bonding layer bonded to the dicing tape.

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