Method for manufacturing cutting tape and semiconductor devices using cutting tape

Abstract

The subject of this invention is to provide a cutting tape with excellent pick-up performance in the manufacturing process of a semiconductor device, which (1) effectively cuts the die-bonding film by cold expansion and forms partial peeling, and (2) when picked up, the semiconductor wafer with the die-bonding film attached after being cut will not be bonded again. The solution is a cutting tape, which consists of a substrate film with an average Young's modulus in the MD direction and an elastic modulus at 5% elongation in the TD direction of 165~260MPa at 0℃, and an adhesive layer. The adhesive layer contains 2.4~7.0 parts by mass of a polyisocyanate crosslinking agent relative to 100 parts by mass of an acrylic adhesive polymer with reactive carbon-carbon double bonds and a hydroxyl value of 12.0~40.5mgKOH / g. The equivalent ratio (-NCO / -OH) of the isocyanate groups in the polyisocyanate crosslinking agent to the hydroxyl groups in the acrylic adhesive polymer is 0.14~1.32. The adhesion to a stainless steel plate at 23℃ under oxygen-induced ultraviolet irradiation is less than 3.50N / 25mm, and the adhesion to a stainless steel plate under oxygen-induced ultraviolet irradiation is 0.25~0.70N / 25mm.

Description

Technical Field

[0001] The present invention relates to a dicing tape that can be used in a semiconductor device manufacturing process and a method for manufacturing a semiconductor device using the dicing tape. Prior Art

[0002] In the manufacture of semiconductor devices, a dicing tape or a dicing die-bonding film obtained by integrating the dicing tape with a die-bonding film is used.

[0003] Dicing tape is a base film with an adhesive layer applied to it. It is used to secure the individual semiconductor wafers during dicing, preventing them from scattering. The individual semiconductor wafers are then peeled from the adhesive layer of the dicing tape and attached to a lead frame, wiring board, or other adherend, such as a semiconductor wafer, using a separate adhesive or film.

[0004] A dicing film (sometimes referred to as "bonding film" or "adhesive layer") is applied to the adhesive layer of dicing tape in a removable manner. In semiconductor device manufacturing, the dicing film is used to place or laminate singulated or unsingulated semiconductor wafers onto the film to produce individual semiconductor chips with dicing film attached. The semiconductor chips with dicing film attached are then lifted from the adhesive layer of the dicing tape using a lifting jig (e.g., a push pin) and peeled (picked up) along with the die-bonding film. The chips are then attached to a lead frame, wiring board, or other adherend, such as a semiconductor chip, through the die-bonding film.

[0005] From the perspective of improving productivity, the above-mentioned dicing bonding film is suitable as a method for obtaining semiconductor chips with a bonding film using the dicing bonding film. In recent years, a method called SDBG (Stealth Dicing Before Griding) has been proposed, which can suppress chipping when singulating thin-filmed semiconductor wafers into chips, replacing the previous full-cut cutting method performed by a high-speed rotating cutting knife.

[0006] In this method, a semiconductor wafer is first attached to back-grinding tape. Laser light is then irradiated into the interior of the semiconductor wafer along the intended dicing lines of the semiconductor wafer. This selectively forms a modified region at a specific depth from the surface of the semiconductor wafer, without completely severing the semiconductor wafer. The back surface is then ground to a specific thickness while appropriately adjusting the grinding amount. The grinding load of the grinding wheel singulates the semiconductor wafers on the back-grinding tape. The singulated semiconductor wafers on the back-grinding tape are then attached to a dicing die-bonding film, which is then transferred from the back-grinding tape to the dicing die-bonding film. The dicing tape is then expanded (hereinafter sometimes referred to as "cold expansion") at a low temperature (e.g., -30°C to 0°C) to separate the low-temperature embrittled die-bonding film into the shapes of the individual semiconductor wafers. Finally, the adhesive layer of the dicing tape is peeled off by pick-up, yielding semiconductor wafers with die-bonding films attached.

[0007] In the above-mentioned picking-up step, after the semiconductor wafer with the die-bonding film is cut, the dicing tape is expanded at near room temperature (hereinafter sometimes referred to as "room temperature expansion") to increase the distance between adjacent individual semiconductor wafers with the die-bonding film (hereinafter sometimes referred to as "kerf width"). After the expansion, the slack in the circumferential portion of the dicing tape outside the semiconductor wafer holding area generated when the expansion state is released is removed by a heat shrinking step (hereinafter sometimes referred to as "heat shrinking") to make the dicing tape tense to maintain the above-mentioned kerf width. Thereafter, the cut individual semiconductor wafers with the die-bonding film can be peeled off from the adhesive layer of the dicing tape and picked up.

[0008] Patent Document 1 discloses a dicing tape whose adhesive layer contains an acrylic polymer comprising C9-C11 alkyl (meth)acrylate units and hydroxyl-containing (meth)acrylate units, with the C9-C11 alkyl (meth)acrylate unit content ranging from 40 mol% to 85 mol%. The dicing tape of Patent Document 1 uses a C9-C11 alkyl (meth)acrylate to weaken the polarity of the acrylic polymer, thereby suppressing the adhesive layer's affinity for the die-bonding film. This allows the dicing tape to effectively peel the die-bonding film even with minimal lift during the pickup step. [Prior Art Literature] [Patent Document]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2020-194879 Summary of the Invention

[0010] [Problems to be solved by the invention]

[0011] In recent years, with the increasing thinning of semiconductor wafers, wafer cracking has become more common during wire bonding during the multi-stage lamination process. As a solution to this problem, wire-embedded die-bonding films, which also function as spacers, have been proposed. Wire-embedded die-bonding films, which must seamlessly embed the wires during die bonding, tend to be thicker and more fluid (having lower melt viscosity at high temperatures) than conventional general-purpose die-bonding films used to bond semiconductor wafers to leadframes or wiring boards. Consequently, when such wire-embedded die-bonding films are laminated to conventional dicing tape for semiconductor wafer manufacturing, the film sometimes fails to cut neatly along the dimensions of the singulated semiconductor wafers. As one of the solutions, a method has been developed using a dicing tape with a substrate that has a higher tensile stress than conventional dicing tape, allowing the cold-expanded dicing tape to exert sufficient cutting force (external stress) on the die-bonding film adhered to the dicing tape. However, this method has the following new problems.

[0012] That is, during the cold expansion step, when the cold-expanded dicing tape applies a cutting force (external stress) to the die-bonding film adhered to the dicing tape, if the dicing tape's tensile stress at low temperatures is sufficient, the die-bonding film, even the aforementioned wire-embedded type that is difficult to cut, will be neatly cut along the size of the singulated semiconductor wafers. However, in addition to the impact of cutting the die-bonding film, stress away from the die-bonding film is concentrated on the dicing tape portion between the semiconductor wafers due to expansion immediately after cutting. Therefore, when the distance between the semiconductor wafers is increased and the die-bonding film is adjusted to the size of the singulated semiconductor wafers, the edge portion (the peripheral portion) of the die-bonding film may partially peel from the adhesive layer of the dicing tape. As the wiring circuits pre-formed on the surface of the semiconductor chip become increasingly multi-layered, the difference in thermal expansion coefficient between the wiring circuit and the semiconductor chip material also becomes a factor that makes the semiconductor chip prone to warping, thereby tending to facilitate partial peeling of the adhesive layer of the dicing tape from the edge portion of the above-mentioned solid crystal film.

[0013] When the adhesive layer of a dicing tape is composed of an adhesive composition that is hardened by active energy rays (e.g., ultraviolet rays), the adhesive layer is hardened by ultraviolet radiation before the semiconductor wafer with a die-bonding film attached is removed from the dicing tape to reduce its adhesion. However, as mentioned above, when the edge of the die-bonding film of the semiconductor wafer with a die-bonding film is peeled off from the adhesive layer of the dicing tape, the adhesive layer is exposed to oxygen in the air at the peeled portion. Therefore, even with ultraviolet radiation, a reaction between growing polymer radicals and oxygen occurs, halting the growth of the polymerization chain. This inhibits the polymerization of the active energy ray-hardening adhesive composition, and as a result, the adhesive layer may not fully cure. In this case, the adhesion of the adhesive layer is not sufficiently reduced. Therefore, in the picking-up step, when the suction claws for picking up the semiconductor wafer with the bond film on the dicing tape on the pushing-up jig are brought into contact with / landed on the surface of the semiconductor wafer from above, the edge of the bond film of the semiconductor wafer with the bond film that has been peeled off from the adhesive layer of the dicing tape will be strongly re-fixed to the adhesive layer that has not been sufficiently hardened due to ultraviolet radiation, even if the jig is pushed up from the bottom side of the dicing tape and sucked / pulled up with the suction claws, to the extent that the semiconductor wafer with the bond film cannot be easily peeled off from the adhesive layer 2, thereby hindering the picking-up of the semiconductor wafer with the bond film.

[0014] On the other hand, although it is possible to consider eliminating the above-mentioned peeling by strengthening the adhesion of the adhesive layer to the solid crystal film, in this case, the force required to peel the solid crystal film by the adhesive layer after ultraviolet radiation during picking up will also become greater, and there is a tendency for the picking performance to decrease, so it cannot be said to be a good solution.

[0015] In the above-mentioned picking step, the die-bonding film of the semiconductor wafer with the die-bonding film attached is peeled off from the adhesive layer of the dicing tape after ultraviolet irradiation by the dicing tape by pushing up the jig from the bottom side of the dicing tape. As the upward push amount of the jig increases, the die-bonding film starts to be peeled off from the edge part, and then peels off from the edge part toward the center part. However, the force required for the initial peeling of the edge part, in other words, the force required to create the peeling opportunity, is usually the largest.

[0016] From this perspective, peeling off the edge of the bond film formed in the aforementioned expansion step before the pickup step also appears to have a beneficial effect on the peeling process during the pickup step. However, as mentioned above, due to the poor curing effect caused by oxygen barriers unique to the adhesive layer composed of conventional active energy ray-curable adhesive compositions, when the pickup collet contacts / landed the semiconductor wafer with the bond film on the dicing tape on the push-up jig during the pickup step, the edge of the bond film on the semiconductor wafer peeled off from the adhesive layer of the dicing tape will be strongly reattached to the extent that the semiconductor wafer with the bond film cannot be easily peeled off from the adhesive layer 2, even if the jig is pushed up from the bottom side of the dicing tape and the suction collet is sucked / pulled up by the adhesive layer, which has not been sufficiently cured due to ultraviolet irradiation. This, in turn, creates a disadvantageous situation.

[0017] Here, if it is assumed that an adhesive layer composed of an active energy ray-hardening adhesive composition can be found that is less susceptible to oxygen barriers than adhesive layers composed of conventional active energy ray-hardening adhesive compositions, then in the expansion step before the pick-up step, when the adhesive layer is intentionally peeled off from the edge portion of the solid film of the semiconductor chip with the solid film, the influence caused by the above-mentioned re-adhesion can be greatly suppressed. That is, by pushing up the jig from the bottom side of the dicing tape and sucking / pulling up with the adsorption claws, the re-adhesion force can be weakened to a level that allows the semiconductor chip with the solid film to be easily peeled off from the adhesive layer 2 after ultraviolet irradiation. Compared with the past, it is more appropriate to say that the force required to peel off the edge portion of the cut solid film can be smaller, and the problem can be solved, thereby obtaining the possibility of good pickup. However, at present, there is no dicing tape that uses an adhesive layer composed of an active energy ray-curable adhesive composition that is not easily inhibited by polymerization due to oxygen. There is still room for research on the development of a dicing tape that can advantageously utilize the peeling of the edge portion of the die-bonding film formed by such an expansion step.

[0018] The present invention is intended to solve the above-mentioned conventional problems. Its purpose is to provide a dicing tape and a dicing tape with excellent pick-up properties for semiconductor wafers with a die-bonding film, which (1) can effectively cut a die-bonding film by cold expansion, and in the cut die-bonding film, the edge portion (the peripheral portion) thereof is peeled off from the adhesive layer of the dicing tape, and (2) can significantly suppress the phenomenon that the edge portion of the die-bonding film peeled off from the adhesive layer is strongly reattached to the adhesive layer of the dicing tape after ultraviolet irradiation to the extent that it cannot be easily peeled off, even when the jig is pushed up from the bottom side of the dicing tape and the suction claws are used to suck / pull it up during pickup. Another purpose is to provide a method for manufacturing a semiconductor device using the dicing tape. [Methods used to solve the problem]

[0019] The present invention provides a cutting tape, which is A dicing tape comprising a substrate film and an adhesive layer containing an active energy ray-curable adhesive composition located on the substrate film, wherein The substrate film has an elastic modulus at 5% elongation in the MD direction (the direction of flow of the substrate film during film formation) at 0°C as Y MD, and an elastic modulus at 5% elongation in the TD direction (a direction perpendicular to the MD direction) at 0°C as Y TD, and an average value of the respective elastic moduli at 5% elongation (Y MD + Y TD) / 2 is within a range of 165 MPa or more and 260 MPa or less. The active energy ray-curable adhesive composition comprises an acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups, a photopolymerization initiator, and a polyisocyanate crosslinking agent that reacts with the hydroxyl groups. The acrylic adhesive polymer has a hydroxyl value within the range of 12.0 mgKOH / g to 40.5 mgKOH / g. The polyisocyanate crosslinking agent is contained in an amount within the range of 2.4 parts by mass to 7.0 parts by mass per 100 parts by mass of the acrylic adhesive polymer. The equivalent ratio (-NCO / -OH) of the isocyanate group (-NCO) of the polyisocyanate crosslinking agent to the hydroxyl group (-OH) of the acrylic adhesive polymer is adjusted within the range of 0.14 to 1.32. The adhesive layer of the aforementioned dicing tape has an adhesion strength A of not more than 3.50 N / 25 mm after UV irradiation (UV integrated radiation dose: 150 mJ / m², peel angle: 90°, peel speed: 300 mm / min) on a stainless steel plate (SUS304・BA plate) at 23°C in the presence of oxygen. The adhesion strength B of the aforementioned dicing tape has an adhesion strength B of not less than 0.25 N / 25 mm and not more than 0.70 N / 25 mm after UV irradiation (UV integrated radiation dose: 150 mJ / m², peel angle: 90°, peel speed: 300 mm / min) on a stainless steel plate (SUS304・BA plate) at 23°C in the absence of oxygen.

[0020] In one embodiment, the substrate film is a resin film composed of a resin composition comprising a thermoplastic cross-linked resin (IO) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer and a polyamide resin (PA).

[0021] In one embodiment, the active energy ray-curable adhesive composition contains at least three types of photopolymerization initiators as the photopolymerization initiators: an α-aminoalkylphenone-based photopolymerization initiator (a), an alkylphenone-based photopolymerization initiator other than the α-aminoalkylphenone-based photopolymerization initiator (b), and an acylphosphine oxide-based photopolymerization initiator (c).

[0022] In one embodiment, the respective contents of the α-aminoalkylphenone-based photopolymerization initiator (a), the alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator, and the acylphosphine oxide-based photopolymerization initiator (c) are such that, relative to 100 parts by mass of the acrylic adhesive polymer, the α-aminoalkylphenone-based photopolymerization initiator (a) is in the range of 0.8 parts by mass to 5.0 parts by mass, the alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator is in the range of 0.2 parts by mass to 5.0 parts by mass, and the acylphosphine oxide-based photopolymerization initiator (c) is in the range of 0.2 parts by mass to 2.0 parts by mass.

[0023] In one embodiment, the ratio A / B of the adhesive force A after ultraviolet irradiation in the presence of oxygen to the adhesive force B after ultraviolet irradiation in the absence of oxygen is in a range of 3.00 to 5.00.

[0024] In one embodiment, the dicing tape is used to expand (stretch) a thin layer of a die-bonding film and a plurality of singulated semiconductor chips sequentially laminated on the adhesive layer at a temperature between -30°C and 0°C, and to cut the die-bonding film in accordance with the shape of the singulated semiconductor chips.

[0025] In one embodiment, the dicing tape, to which the sheet-like laminate is bonded, is subjected to a temperature range of -30°C to 0°C, and is expanded to cut the die-bonding film in accordance with the shape of the singulated semiconductor wafers, so that the edge portions (the four peripheral portions) of the die-bonding film are peeled off from the adhesive layer.

[0026] In one embodiment, the ratio of the area of ​​the edge portion (the four-sided portion) of the die-bonding film separated from the adhesive layer to the entire area of ​​the severed die-bonding film is within a range of 10% to 45%.

[0027] Furthermore, the present invention provides a method for manufacturing a semiconductor device using the dicing tape. [Effects of the Invention]

[0028] According to the present invention, there is provided a dicing tape having excellent pick-up properties, which (1) effectively cuts a die-bonding film by cold expansion, and forms a state in which the edge portion (the four peripheral portions) of the cut die-bonding film is peeled off from the adhesive layer of the dicing tape, and (2) greatly suppresses the phenomenon in which the edge portion of the die-bonding film peeled off from the adhesive layer is strongly reattached to the adhesive layer of the dicing tape after ultraviolet irradiation to a degree that makes it difficult to peel off even when the dicing tape is pushed up by a jig from the bottom side and sucked / pulled up by a suction claw. Furthermore, a method for manufacturing a semiconductor device using the dicing tape is provided. Simple diagram description

[0029] FIG. 1 is a cross-sectional view showing an example of the structure of a base film to which the dicing tape of this embodiment is applied. FIG. 2 is a cross-sectional view showing an example of the structure of a dicing tape to which this embodiment is applied. FIG. 3 is a cross-sectional view showing an example of a dicing die-bonding film having a structure in which the dicing tape according to the present embodiment is bonded to the die-bonding film. [Figure 4] Schematic diagram of a peel-angle-free type adhesive / film peeling analysis device used to measure the adhesive strength of dicing tape, viewed from directly above. [Figure 5] A flow chart illustrating a method for manufacturing dicing tape. [Figure 6] A flow chart illustrating a method for manufacturing a semiconductor chip. FIG7 is a perspective view showing a state where a ring frame (wafer ring) is attached to the outer edge of a dicing bonding film and a singulated semiconductor wafer is attached to the center of the bonding film. [Figure 8] (a) to (f) are cross-sectional views showing an example of a grinding step of a semiconductor wafer in which a plurality of modified regions are formed by laser light irradiation, and a step of bonding a plurality of cut semiconductor wafers to a dicing bonding film. [Figure 9] (a) to (f) are cross-sectional views showing an example of manufacturing a semiconductor chip using a plurality of cut thin film semiconductor wafers bonded with a dicing bonding film. FIG10 is an enlarged cross-sectional view showing an example of a state in which the edge portion (the four peripheral portions) of a cut die-bonding film is partially peeled off from the adhesive layer of the dicing tape. FIG11 is an enlarged plan view showing a state where the edge portion (the four peripheral portions) of the cut die-bonding film is partially peeled off from the adhesive layer of the dicing tape, as viewed from the back side (base film side) of the semiconductor wafer. FIG. 12 is a schematic cross-sectional view of one embodiment of a semiconductor device constructed by laminating semiconductor wafers using a dicing bonding film having a structure in which the dicing tape according to the present embodiment is bonded to a bonding film. FIG. 13 is a schematic cross-sectional view of another embodiment of a semiconductor device using a semiconductor wafer manufactured using a dicing die-bonding film having a structure in which the dicing tape according to the present embodiment is bonded to the die-bonding film. Implementation Method

[0030] The following describes in detail suitable embodiments of the present invention with reference to the accompanying drawings as needed. However, the present invention is not limited to the following embodiments.

[0031] <Composition of Dicing Tape and Die Bonding Film> Figures 1 (a) through (d) are cross-sectional views illustrating an example of the structure of a base film 1 used in the dicing tape of this embodiment. The base film 1 of the dicing tape of this embodiment can be a single layer of a single resin composition (see Figure 1 (a) 1-A), a laminate composed of multiple layers of the same resin composition (see Figure 1 (b) 1-B), or a laminate composed of multiple layers of different resin compositions (see Figure 1 (c) 1-C and Figure 1 (d) 1-D). In the case of a laminate composed of multiple layers, the number of layers is not particularly limited, but is preferably in the range of 2 to 5 layers.

[0032] Figure 2 is a cross-sectional view showing an example of the structure of a dicing tape to which this embodiment is applied. As shown in Figure 2, dicing tape 10 has a structure comprising an adhesive layer 2 on the first surface of a base film 1. Furthermore, although not shown, a releasable base sheet (release liner) may also be provided on the surface of the adhesive layer 2 of dicing tape 10 (the surface opposite to the surface facing the base film 1). The base film 1 is composed of a resin film having an elastic modulus at 5% elongation (Y MD) in the MD direction (the direction of flow during film formation) at 0°C and an elastic modulus at 5% elongation (Y TD) in the TD direction (a direction perpendicular to the MD direction) at 0°C. The average value of the respective elastic moduli at 5% elongation (Y MD + Y TD) / 2 is within a range of 165 MPa to 260 MPa. The adhesive forming the adhesive layer 2 may be, for example, an active energy ray-curable acrylic adhesive that hardens and shrinks upon irradiation with active energy rays such as ultraviolet rays (UV) to reduce the adhesive force to the adherend.

[0033] The dicing tape 10 of this configuration is used, for example, as follows in the semiconductor manufacturing process. Multiple singulated semiconductor wafers, obtained by back grinding a semiconductor wafer with dicing grooves formed on the surface by a blade or a semiconductor wafer with a modified layer formed internally by laser, are attached and held (temporarily fixed) on the adhesive layer 2 of the dicing tape 10 via a die-bonding film (adhesive layer). The die-bonding film is cut according to the shapes of the individual singulated semiconductor wafers by cold expansion. The kerf width between the semiconductor wafers is then fully expanded by room-temperature expansion and heat shrinking steps. The individual semiconductor wafers with the die-bonding film attached are then peeled from the adhesive layer 2 of the dicing tape 10 by a pickup step. The resulting semiconductor wafers with the die-bonding film attached are then attached to an adherend such as a lead frame, a wiring board, or another semiconductor wafer.

[0034] Figure 3 is a cross-sectional view showing an example of a so-called dicing film, which is a structure in which the dicing tape 10 according to this embodiment is bonded and integrated with a die-bonding film (adhesive film) 3. As shown in Figure 3, the dicing film 20 has a structure in which the die-bonding film (adhesive film) 3 is bonded and releasably laminated onto the adhesive layer 2 of the dicing tape 10.

[0035] The dicing bonding film 20 of this configuration is used, for example, in the following manner during semiconductor manufacturing. Multiple singulated semiconductor wafers, obtained by back grinding a semiconductor wafer with dividing grooves formed on its surface by a blade or a semiconductor wafer with a modified layer formed internally by laser, are attached and held (bonded) on the bonding film 3 of the dicing bonding film 20. Cold expansion is then performed to separate the low-temperature embrittled bonding film 3 according to the shape of the individual semiconductor wafers, yielding individual semiconductor wafers with bonding films attached. After the kerf width between the semiconductor wafers with bonding films is sufficiently expanded through room-temperature expansion and heat shrinking steps, the individual semiconductor wafers with bonding films attached are peeled from the adhesive layer 2 of the dicing tape 10 through a pickup step. The resulting semiconductor wafers with bonding films attached (bonding films) 3 are bonded to an adherend such as a lead frame, a wiring board, or another semiconductor wafer via the bonding film (bonding films) 3. Furthermore, although not shown in the figure, the surface of the adhesive layer 2 of the dicing tape 10 (the surface opposite to the surface facing the base film 1) and the surface of the die-bonding film 3 (the surface opposite to the surface facing the adhesive layer 2) may also be provided with a releasable base sheet (peel-off liner), which can be appropriately peeled off during use.

[0036] <Dicing Tape> (Base film) The base film 1 , which is the first component of the dicing tape 10 of the present invention, will be described below.

[0037] [Elastic modulus of base film at 5% elongation at 0°C] The substrate film 1 is a resin film having an elastic modulus at 5% elongation (Y MD) in the MD direction (the direction of flow during film formation) at 0°C and an elastic modulus at 5% elongation (Y TD) in the TD direction (a direction perpendicular to the MD direction) at 0°C. The average value of the elastic modulus at 5% elongation (Y MD + Y TD) / 2 of each value (Y MD + Y TD) / 2 is preferably within the range of 165 MPa to 260 MPa. The average value of the elastic modulus at 5% elongation (Y MD + Y TD) / 2 of the substrate film 1 at 0°C is preferably within the range of 190 MPa to 240 MPa. Thus, the average value is preferably 165 MPa or greater, more preferably 190 MPa or greater. Furthermore, the average value is preferably 260 MPa or less, more preferably 240 MPa or less. []

[0038] If the average modulus of elasticity (Y MD + Y TD) / 2 of the base film 1 at 5% elongation at 0°C is less than 165 MPa, even when the dicing tape 10 is expanded, stress away from the cut die-bonding film is less likely to act. Consequently, the edges (peripheral portions) of the cut die-bonding film may not be partially separated from the adhesive layer 2 of the dicing tape 10. Furthermore, even at low temperatures, external stress applied to the dicing tape 10 by expansion is not sufficiently transmitted to the die-bonding film 3. Therefore, particularly when using a wire-embedded die-bonding film, there is a risk that the die-bonding film 3 may not be properly severed during the cold expansion step. Furthermore, if the value of (Y MD + Y TD) / 2 is too small, the dicing tape 10 becomes soft, making handling difficult or failing to ensure a sufficient kerf width. As a result, the pickup performance may not be improved compared to conventional methods, or may be reduced.

[0039] On the other hand, if the average modulus of elasticity (Y MD + Y TD) / 2 of the base film 1 at 5% elongation at 0°C exceeds 260 MPa, the dicing tape 10 may become difficult to expand. Even if expansion is possible, the die-bonding film 3 may peel excessively from the adhesive layer 2 during expansion, preventing sufficient external stress from being applied uniformly throughout the adhesive layer 2. This may result in the die-bonding film 3 not being cut cleanly, or the incision width may not be sufficiently maintained or may vary. Furthermore, during the pickup step, when the excessively peeled die-bonding film reattaches to the adhesive layer 2, the reattachment area becomes excessively large. Therefore, even if the adhesive layer 2 is composed of an active energy ray-curable adhesive composition that meets the requirements of the present invention, peeling the dicing tape 10 from the bottom side by pushing it up with a jig may require a large amount of energy due to the large reattachment area. As a result, the pickup efficiency of semiconductor wafers with die-bonding films may be reduced.

[0040] By ensuring that the average modulus of elasticity (Y MD + Y TD) / 2 of the base film 1 at 5% elongation at 0°C is within the range of 165 MPa to 260 MPa, the dicing tape 10 can impart sufficient external stress to the bonding film 3 during the cold expansion step to sever the bonding film 3 adhered to the adhesive layer 2 containing the specific active energy ray-curable adhesive composition described below. Furthermore, the adhesive layer 2 of the dicing tape 10 can be subjected to stress in a direction away from the bonding film 3 necessary to achieve a suitable separation between the edge of the severed bonding film and the adhesive layer 2. Furthermore, since the stress imparted to the bonding film 3 and adhesive layer 2 is appropriately suppressed, a sufficient kerf width can be ensured without excessive separation of the severed bonding film from the adhesive layer 2. This also prevents damage to the semiconductor wafers caused by collisions and displacement from their fixed positions on the adhesive layer 2. At this time, if the adhesive layer 2 is composed of an active energy ray-curable adhesive composition that meets the requirements of the present invention, the pickup performance of the semiconductor wafer with the die-bonding film can be improved compared to the past.

[0041] The elastic modulus Y MD at 5% elongation in the MD direction and the elastic modulus Y TD at 5% elongation in the TD direction of the substrate film 1 described above at 0°C were measured by the following method. Specifically, a test piece with a length of 100 mm (MD direction) and a width of 10 mm (TD direction) was prepared as a sample for MD measurement (N = 5 samples); and a test piece with a length of 100 mm (TD direction) and a width of 10 mm (MD direction) was prepared as a sample for TD measurement (N = 5 samples). Next, using a tension-compression testing machine (Model: Minebea TechnoGraph TG-5kN) manufactured by Minebea Mitsumi Co., Ltd., the test piece was fixed with chucks at both ends of the longitudinal direction so that the initial distance between the chucks was 20 mm. The test piece was placed in a thermostatic bath (Model: THB-A13-038) manufactured by Minebea Mitsumi Co., Ltd. at 0°C for 1 minute, and then a tensile test was performed at a speed of 100 mm / min to obtain a tensile load / elongation curve. From the obtained tensile load-elongation curve, the slope of the straight line connecting the origin (elongation start point) and the tensile load value (unit: N) corresponding to an elongation of 1.0 mm from the origin (5% elongation relative to the initial distance between the chucks of 20 mm) was calculated using the following formula:

[0042] Modulus of elasticity at 5% elongation Y (unit: MPa) = (slope) × [(initial distance between chucks) / (cross-sectional area of ​​test piece)]

[0043] The elastic modulus Y of the base film 1 at 5% elongation is determined. Measurements were performed using 5 samples (N) in each direction, and the average values ​​were defined as the elastic modulus at 5% elongation in the MD direction (Y MD) and the elastic modulus at 5% elongation in the TD direction (Y TD). The average elastic modulus at 5% elongation at 0°C of the substrate film 1 of the present invention is (Y MD + Y TD) / 2, calculated using these values.

[0044] [Resin composition constituting the base film] The resin composition constituting the substrate film 1 is not particularly limited as long as the average value of the elastic modulus (Y MD + Y TD) / 2 at 5% elongation of the substrate film 1 at 0°C is within the above-mentioned range. From the perspective of achieving a balance between expandability and thermal shrinkage, a resin composition containing a thermoplastic crosslinked resin is preferred. Specifically, examples of such resin compositions include a resin composition containing a thermoplastic crosslinked resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer (hereinafter sometimes simply referred to as an "ionomer"), or a resin composition containing a thermoplastic crosslinked resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer and a polyamide resin (PA). Resin films produced using these resin compositions can be suitably used as the substrate film 1. Among these resin compositions, a resin composition comprising a thermoplastic cross-linked resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer (hereinafter sometimes simply referred to as "ionomer") and a polyamide resin (PA) is particularly suitable for the dicing tape 10 using the above-mentioned substrate film, especially for applications in wire-embedded die bonding films, as it can provide a better balance between the two physical properties of low-temperature expandability and thermal shrinkage.

[0045] The total amount of the thermoplastic crosslinked resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer and the polyamide resin (PA) in the substrate film 1 as a whole is not particularly limited as long as the average value of the elastic modulus at 5% elongation at 0°C (Y MD + Y TD) / 2 of the substrate film 1 is within the above-mentioned range. The total amount is preferably 65% ​​by mass or more and 100% by mass or less, based on the total amount of the resin composition constituting the substrate film 1 as a whole. It is more preferably 75% by mass or more and 100% by mass or less, and particularly preferably 85% by mass or more and 100% by mass or less.

[0046] Dicing tape 10 using a base film 1 having such a structure, in a configuration where a die-bonding film 3 is bonded to an adhesive layer 2, can exert an appropriate breaking force (external stress) on the die-bonding film 3 by stretching at low temperatures. Therefore, it is suitable for use in cold expansion steps and further room-temperature expansion steps in the manufacturing process of semiconductor devices. Specifically, it is suitable for effectively separating the die-bonding film 3 according to the shape of each singulated semiconductor wafer during the cold expansion step, thereby obtaining individual semiconductor wafers with die-bonding films of a specific size with a high yield. Furthermore, since the cold expansion of dicing tape 10, which is performed immediately after the die-bonding film 3 is cut, exerts an appropriate stress on the adhesive layer 2 of dicing tape 10 in a direction away from each cut die-bonding film. This allows each cut die-bonding film to be appropriately and intentionally partially peeled from the adhesive layer 2 of dicing tape 10 at its edges (the four peripheral portions). Furthermore, in the room temperature expansion step, the expansibility required to fully ensure the kerf width between semiconductor wafers is maintained.

[0047] [Resin composition containing a thermoplastic cross-linked resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer and a polyamide resin (PA)] As described above, a preferred embodiment of the substrate film 1 of the present invention is a resin film composed of a resin composition containing a thermoplastic crosslinked resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer and a polyamide resin (PA). The thermoplastic crosslinked resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer and the polyamide resin (PA) are described below.

[0048] [Thermoplastic cross-linked resin (IO) composed of ionic polymer of ethylene / unsaturated carboxylic acid copolymer] In the substrate film 1 of this embodiment, the thermoplastic crosslinked resin (10) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer is a resin in which the carboxyl groups of the ethylene / unsaturated carboxylic acid copolymer are partially or completely neutralized (crosslinked) with metal (ions). In the following description, "a thermoplastic crosslinked resin composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer" may be referred to as "a resin composed of an ionomer" or simply as "an ionomer."

[0049] The ethylene / unsaturated carboxylic acid copolymer constituting the ionomer is at least a binary copolymer obtained by copolymerizing ethylene and an unsaturated carboxylic acid, and may also be a ternary or higher copolymer obtained by further copolymerizing a third copolymer component. Furthermore, the ethylene / unsaturated carboxylic acid copolymer may be used singly or in combination of two or more.

[0050] Examples of the unsaturated carboxylic acid constituting the ethylene / unsaturated carboxylic acid binary copolymer include unsaturated carboxylic acids having 4 to 8 carbon atoms, such as acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, maleic acid, and maleic anhydride. Acrylic acid or methacrylic acid is particularly preferred.

[0051] When the ethylene / unsaturated carboxylic acid copolymer is a ternary or higher multi-component copolymer, in addition to the ethylene and unsaturated carboxylic acid constituting the binary copolymer, a third copolymer component may also be included to form the multi-component copolymer. Examples of the third copolymer component include unsaturated carboxylic acid esters (e.g., (meth)acrylic acid alkyl esters with 1 to 12 carbon atoms in the alkyl group, such as methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, dimethyl maleate, diethyl maleate, etc.), unsaturated hydrocarbons (e.g., propylene, butene, 1,3-butadiene, pentene, 1,3-pentadiene, 1-hexene, etc.), vinyl esters (e.g., vinyl acetate, vinyl propionate, etc.), vinyl sulfate or vinyl nitrate, halogen compounds (e.g., vinyl chloride, vinyl fluoride, etc.), primary and secondary amine compounds containing a vinyl group, carbon monoxide, sulfur dioxide, etc. These copolymer components are preferably unsaturated carboxylic acid esters.

[0052] The ethylene / unsaturated carboxylic acid copolymer may be in the form of a block copolymer, a random copolymer, or a graft copolymer; and may be in the form of a binary copolymer or a ternary copolymer. From the perspective of industrial availability, binary random copolymers, ternary random copolymers, graft copolymers of binary random copolymers, or graft copolymers of ternary random copolymers are particularly preferred; binary random copolymers or ternary random copolymers are even more preferred. From the perspective of extensibility, ternary random copolymers are particularly preferred because they are less likely to neck during expansion.

[0053] Specific examples of the ethylene / unsaturated carboxylic acid copolymers include binary copolymers such as ethylene / acrylic acid copolymers and ethylene / methacrylic acid copolymers, and terpolymers such as ethylene / methacrylic acid / 2-methyl-propyl acrylate copolymers. Commercially available ethylene / unsaturated carboxylic acid copolymers may also be used, for example, the Nucrel series (registered trademark) manufactured by DuPont-Mitsui Polychemicals.

[0054] In the above-mentioned ethylene / unsaturated carboxylic acid copolymer, the copolymerization ratio (mass ratio) of the unsaturated carboxylic acid ester is preferably in the range of 1% by mass to 20% by mass. From the perspective of expandability and heat resistance (adhesion and melting) during the expansion step, it is more preferably in the range of 5% by mass to 15% by mass. Thus, the copolymerization ratio is preferably 1% by mass or more, more preferably 5% by mass or more. Furthermore, the copolymerization ratio is preferably 20% by mass or less, more preferably 15% by mass or less. []

[0055] In the substrate film 1 of this embodiment, the ionomer used as the resin (10) is preferably one in which the carboxyl groups contained in the above-mentioned ethylene / unsaturated carboxylic acid copolymer are crosslinked (neutralized) with metal ions in any ratio. Examples of the metal ions used to neutralize the acid groups include lithium ions, sodium ions, potassium ions, rubidium ions, cesium ions, zinc ions, magnesium ions, and manganese ions. Among these metal ions, magnesium ions, sodium ions, and zinc ions are particularly preferred due to their ease of obtaining industrial products; sodium ions and zinc ions are even more preferred.

[0056] The degree of neutralization of the ethylene / unsaturated carboxylic acid copolymer in the ionomer is preferably in the range of 20 mol% to 85 mol%, more preferably 50 mol% to 82 mol%, and particularly preferably 65 mol% to 80 mol%. Thus, the degree of neutralization is preferably 20 mol% or more, more preferably 50 mol% or more, and particularly preferably 65 mol% or more. Furthermore, the degree of neutralization is preferably 85 mol% or less, more preferably 82 mol% or less, and particularly preferably 80 mol% or less. By achieving a degree of neutralization of 20 mol% or more, the cutting properties of the die-bonding film 3 can be further improved, and the heat shrinkage of the dicing tape 10 in the heat shrinking step described later can also be improved. By achieving a degree of neutralization of 85 mol% or less, the film forming properties of the film can be further improved. The degree of neutralization refers to the ratio (molar %) of metal ions incorporated relative to the molar number of acid groups, especially carboxyl groups, in the ethylene / unsaturated carboxylic acid copolymer.

[0057] The resin (10) composed of the ionomer has a melting point of approximately 85-100°C. The melt flow rate (MFR) of the resin (10) composed of the ionomer is preferably in the range of 0.2 g / 10 min to 20.0 g / 10 min, more preferably in the range of 0.5 g / 10 min to 20.0 g / 10 min, and even more preferably in the range of 0.5 g / 10 min to 18.0 g / 10 min. When the melt flow rate is within the above range, the film forming properties of the substrate film 1 are excellent. Thus, the MFR is preferably 0.2 g / 10 min to 0.5 g / 10 min to 10.5 g / 10 min, more preferably 20.0 g / 10 min to 18.0 g / 10 min, and even more preferably 18.0 g / 10 min to 10.5 g / 10 min. The MFR is a value measured at 190° C. and a load of 2160 g by a method in accordance with JIS K7210-1999.

[0058] The resin composition constituting the substrate film 1 of this embodiment preferably contains a polyamide resin (PA) in addition to the resin (IO) composed of the ionomer of the ethylene / unsaturated carboxylic acid copolymer. The mass ratio (IO):(PA) of the resin (IO):(PA) of the ionomer of the ethylene / unsaturated carboxylic acid copolymer is preferably in the range of 72:28 to 95:5. By mixing the resin composition in the above mass ratio to form the substrate film 1, the average value of the elastic modulus (Y MD + Y TD) / 2 at 5% elongation at 0°C of the substrate film 1 can be easily adjusted to the above range. The above mass ratio (IO):(PA) is more preferably in the range of 74:26 to 92:8, and even more preferably in the range of 80:20 to 90:10. The upper and lower limits of the numerical ranges in this specification can be arbitrarily selected and combined.

[0059] [Polyamide resin (PA)] Examples of the polyamide resin (PA) include polycondensates of carboxylic acids such as oxalic acid, adipic acid, sebacic acid, dodecanoic acid, terephthalic acid, isophthalic acid, and 1,4-cyclohexanedicarboxylic acid, and diamines such as ethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, decamethylenediamine, 1,4-cyclohexanediamine, and m-phenylenediamine; ring-opening polymers of cyclic lactamides such as ε-caprolactam and ω-laurolactam; polycondensates of aminocarboxylic acids such as 6-aminocaproic acid, 9-aminononanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid; and copolymers of the above-mentioned cyclic lactamides, dicarboxylic acids, and diamines.

[0060] Commercially available polyamide resins (PA) can also be used. Specific examples include nylon 4 (melting point 268°C), nylon 6 (melting point 225°C), nylon 46 (melting point 240°C), nylon 66 (melting point 265°C), nylon 610 (melting point 222°C), nylon 612 (melting point 215°C), nylon 6T (melting point 260°C), nylon 11 (melting point 185°C), nylon 12 (melting point 175°C), copolymer nylons (e.g., nylon 6 / 66, nylon 6 / 12, nylon 6 / 610, nylon 66 / 12, nylon 6 / 66 / 610, etc.), nylon MXD6 (melting point 237°C), and nylon 46. Among these polyamides, nylon 6 or nylon 6 / 12 is particularly preferred from the perspective of film formability and mechanical properties of the substrate film 1.

[0061] As described above, the content of the polyamide resin (PA) is preferably such that the mass ratio of the resin (IO) composed of the ionomer of the ethylene / unsaturated carboxylic acid copolymer to the polyamide resin (PA) in the entire base film 1 is (IO): (PA) in the range of 72:28 to 95:5. If the mass ratio of the polyamide resin (PA) falls below the above range, particularly if the degree of neutralization of the ionomer of the ethylene / unsaturated carboxylic acid copolymer by the metal ions is low, the base film 1 (dicing tape 10) may not sufficiently increase its Young's modulus at low temperatures. Even when stretched at low temperatures, an appropriate breaking force (external stress) may not be applied to the die-bonding film 3, and the die-bonding film 3 may not be neatly cut. Furthermore, even if the base film 1 (dicing tape 10) is expanded, stress in a direction away from the cut die-bonding film is not easily applied, so there is a risk that the edge portion (the four surrounding portions) of the cut die-bonding film will not be partially peeled off from the adhesive layer 2 of the dicing tape 10.

[0062] On the other hand, if the mass ratio of the polyamide resin (PA) exceeds the above range, stable film formation may become difficult, depending on the resin composition of the base film 1. Furthermore, the base film 1's modulus of elasticity at 5% elongation at low temperatures may increase excessively, making expansion of the dicing tape 10 difficult. Even if expansion is possible, the die-bonding film 3 may peel excessively from the adhesive layer 2 during expansion, preventing sufficient external stress from being applied to the die-bonding film 3 through the adhesive layer 2. This may result in the die-bonding film 3 not being cut cleanly, or the incision width not being sufficiently maintained, or the incision width may vary. Furthermore, the flexibility of the base film 1 may be compromised, making it impossible to maintain the expandability of the dicing tape 10 during the room-temperature expansion step. Furthermore, when picking up a semiconductor wafer with a die-bonding film attached, there is a risk of the semiconductor wafer cracking, leading to pickup failure. The content of the polyamide resin (PA) is preferably such that the mass ratio of the resin (IO) composed of the ionomer of the ethylene / unsaturated carboxylic acid copolymer and the polyamide resin (PA) in the entire substrate film 1 (IO): (PA) is in the range of 74:26 to 92:8, and more preferably in the range of 80:20 to 90:10.

[0063] Furthermore, when the substrate film 1 is a laminate composed of multiple layers, the mass ratio of the resin (IO) composed of the ionic polymer of the ethylene / unsaturated carboxylic acid copolymer to the polyamide resin (PA) means the value in the entire substrate film 1 (laminate) calculated from the mass ratio of the resin (IO) composed of the ionic polymer of the ethylene / unsaturated carboxylic acid copolymer to the polyamide resin (PA) in each layer and the mass ratio of each layer in the entire substrate film 1 (laminate).

[0064] When the mass ratio of the resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer to the polyamide resin (PA) in the entire base film 1 is within the above range, the average value (Y MD + Y TD) / 2 of the elastic modulus at 5% elongation at 0°C of the base film 1 can be easily adjusted to be within the range of 165 MPa to 260 MPa. As a result, during the cold expansion step, the dicing tape 10 can apply sufficient external stress to the die-bonding film 3 to sever the die-bonding film 3 adhered to the adhesive layer 2 containing the specific active energy ray-curable adhesive composition described below. Furthermore, the adhesive layer 2 of the dicing tape 10 can be subjected to stress in a direction away from the die-bonding film 3 necessary to achieve a suitable separation between the edge of the severed die-bonding film and the adhesive layer 2. Furthermore, because the stress applied to the die-bonding film 3 and adhesive layer 2 is appropriately suppressed, the cut width of the die-bonding film can be sufficiently maintained without excessive separation from the adhesive layer 2. This also prevents damage to the semiconductor wafers from colliding with each other and displacement of the fixed position on the adhesive layer 2. In this case, if the adhesive layer 2 is composed of an active energy ray-curable adhesive composition that meets the requirements of the present invention, the pickup performance of the semiconductor wafer with the die-bonding film can be improved compared to conventional methods.

[0065] [other] The resin composition constituting the substrate film 1 may contain other resins or various additives as needed, as long as the effects of the present invention are not impaired. Examples of the other resins include polyolefins such as polyethylene and polypropylene; ethylene / unsaturated carboxylic acid copolymers; or polyetheresteramides. Such other resins may be incorporated in an amount of, for example, 20 parts by mass relative to a total of 100 parts by mass of the resin (IO) comprising the ionic polymer of the ethylene / unsaturated carboxylic acid copolymer and the polyamide resin (PA). Examples of the additives include antistatic agents, antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, pigments, dyes, lubricants, anti-adhesion agents, mildew inhibitors, antibacterial agents, flame retardants, flame retardant aids, crosslinking agents, crosslinking aids, foaming agents, foaming aids, inorganic fillers, and fiber reinforcements. Such various additives can be blended in a ratio of, for example, 5 parts by mass relative to a total of 100 parts by mass of the resin (IO) composed of the ionomer of the ethylene / unsaturated carboxylic acid copolymer and the polyamide resin (PA).

[0066] [Thickness of base film] The thickness of the substrate film 1 is not particularly limited. Considering its use as a dicing tape 10, for example, it is preferably within a range of 70 μm to 120 μm. More preferably, it is within a range of 70 μm to 110 μm. If the thickness of the substrate film 1 is less than 70 μm, the ring frame (wafer ring) may not be adequately retained during the dicing process. Furthermore, if the thickness of the substrate film 1 exceeds 120 μm, residual stress during film formation may be released, leading to increased warpage.

[0067] [Layer composition of base film] The layer composition of the substrate film 1 is not particularly limited and may be a single layer of a single resin composition, a laminate comprising multiple layers of the same resin composition, or a laminate comprising multiple layers of different resin compositions. In the case of a laminate comprising multiple layers, the number of layers is not particularly limited, but is preferably within the range of 2 or more and 5 or less.

[0068] When the substrate film 1 is a laminate composed of a plurality of layers, for example, it may be a structure obtained by laminating a plurality of layers made of the resin composition of the present embodiment, or it may be a structure obtained by laminating a layer made of a resin composition other than the resin composition of the present embodiment on a layer made of the resin composition of the present embodiment.

[0069] Examples of the above-mentioned layer made of a film made of another resin composition include a layer made of a resin composition selected from linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), ethylene-α-olefin copolymer, polypropylene, ethylene / unsaturated carboxylic acid copolymer, ethylene / unsaturated carboxylic acid / unsaturated carboxylic acid alkyl ester terpolymer, ethylene / unsaturated carboxylic acid alkyl ester copolymer, ethylene / vinyl ester copolymer, ethylene / unsaturated carboxylic acid alkyl ester / carbon monoxide copolymer, or a single substance or a blend of any two or more of these unsaturated carboxylic acid grafts; and an ionomer (IO) of the above-mentioned ethylene / unsaturated carboxylic acid copolymer. Among these, from the viewpoint of adhesion and versatility with the resin layer composed of a mixture of a resin (IO) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer according to this embodiment and a polyamide resin (PA), ethylene / unsaturated carboxylic acid copolymer, ethylene / unsaturated carboxylic acid / unsaturated carboxylic acid alkyl ester terpolymer, ethylene / unsaturated carboxylic acid alkyl ester copolymer and ionomers of these copolymers, ethylene-α-olefin copolymer, etc. are particularly preferred.

[0070] As examples of the case where the base film 1 of the present embodiment is composed of a laminated structure, specifically, the following base films having a two-layer structure or a three-layer structure can be cited.

[0071] 2-layer structure, for example (1) [a first resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)] / [a second resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)], (2) [a first resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)] / [a second resin layer composed of a mixture of a resin (IO2) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA2)], (3) [a first resin layer composed of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer] / [a second resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of this embodiment and a polyamide resin (PA1)], (4) A two-layer structure ([first resin layer] / [second resin layer]) consisting of the same resin layer or different resin layers, such as [first resin layer composed of ethylene / unsaturated carboxylic acid copolymer] / [second resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of the ethylene / unsaturated carboxylic acid copolymer of this embodiment and a polyamide resin (PA1)].

[0072] 3-layer structure, for example (5) [a first resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)] / [a second resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)] / [a third resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)], (6) [a first resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)] / [a second resin layer composed of a mixture of a resin (IO2) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA2)] / [a third resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)], (7) [a first resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)] / [a second resin layer composed of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment] / [a third resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)], (8) [a first resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)] / [a second resin layer composed of an ethylene / unsaturated carboxylic acid copolymer] / [a third resin layer composed of a mixture of a resin (IO1) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer of the present embodiment and a polyamide resin (PA1)], (9) [First resin layer composed of a mixture of a resin (101) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer of this embodiment and a polyamide resin (PA1)] / [Second resin layer composed of an ethylene-α-olefin copolymer] / [Third resin layer composed of a mixture of a resin (101) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer of this embodiment and a polyamide resin (PA1)] The three-layer structure ([first resin layer] / [second resin layer] / [third resin layer]) is composed of the same resin layer or different resin layers.

[0073] [Method for forming a film of a substrate film] The film forming method of the substrate film 1 of this embodiment can be a conventional method. A resin composition containing an ionomer resin (IO) and a polyamide resin (PA), along with other necessary components, is melt-kneaded and processed into a film using various molding methods, such as T-die casting, T-die lip molding, blown bag molding, extrusion lamination, and calendering. Furthermore, when the substrate film 1 is a laminate composed of multiple layers, each layer can be individually formed using methods such as calendering, extrusion, and blown bag molding, and then laminated by heat lamination or bonding with an appropriate adhesive to produce a laminate. Examples of such adhesives include the various ethylene copolymers described above, or blends of unsaturated carboxylic acid grafts thereof, either singly or in combination. Alternatively, the resin compositions of each layer can be simultaneously extruded using a coextrusion lamination method to produce a laminate. Furthermore, the surface of the base film 1 adjacent to the adhesive layer 2 may be subjected to a corona treatment or plasma treatment to improve adhesion with the adhesive layer 2 (described later). Furthermore, the surface of the base film 1 opposite to the surface adjacent to the adhesive layer 2 may be subjected to an embossing treatment such as with an embossing roller to stabilize winding of the base film 1 during film formation or to prevent sticking after film formation.

[0074] (Adhesive layer) The adhesive layer 2 containing the active energy ray-curable adhesive composition, which is the second component of the dicing tape 10 of the present invention, will be described below.

[0075] The adhesive layer 2 comprises an active energy ray-curable adhesive composition. As described above, the active energy ray-curable adhesive composition comprises an acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups, a photopolymerization initiator, and a polyisocyanate crosslinking agent that cross-links with the hydroxyl groups. The active energy ray-curable adhesive composition comprises 2.4 parts by mass to 7.0 parts by mass of the polyisocyanate crosslinking agent per 100 parts by mass of the acrylic adhesive polymer having a hydroxyl value in the range of 12.0 mgKOH / g to 40.5 mgKOH / g. The equivalent ratio (-NCO / -OH) of the isocyanate groups (-NCO) in the polyisocyanate crosslinking agent to the hydroxyl groups (-OH) in the acrylic adhesive polymer is adjusted to be within a range of 0.14 to 1.32. The adhesive layer 2 of the dicing tape 10 has an adhesion strength A to a stainless steel plate (SUS304·BA plate) after ultraviolet irradiation in the presence of oxygen in the range of 3.50 N / 25 mm or less at 23°C, and an adhesion strength B to a stainless steel plate (SUS304·BA plate) after ultraviolet irradiation in the absence of oxygen in the range of 0.25 N / 25 mm or more and 0.70 N / 25 mm or less.

[0076] [Acrylic adhesive polymer] The acrylic adhesive polymer contained as a main component in the active energy ray-curable adhesive composition is an acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups, and has a hydroxyl value within the range of 12.0 mgKOH / g to 40.5 mgKOH / g. The acrylic adhesive polymer preferably accounts for 90% to 100% by mass, and more preferably 95% to 100% by mass, of the total mass of the active energy ray-curable adhesive composition.

[0077] The acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups can be obtained by copolymerizing an alkyl (meth)acrylate monomer with a hydroxyl-containing monomer to obtain a copolymer (acrylic adhesive polymer having hydroxyl groups) as a base polymer, and then adding a compound having an isocyanate group and a carbon-carbon double bond (active energy ray-reactive compound) that can undergo an addition reaction with the hydroxyl groups of the copolymer.

[0078] The main chain (main skeleton) of the acrylic adhesive polymer having a hydroxyl group is composed of a copolymer containing at least a (meth)acrylate monomer and a hydroxyl group-containing monomer as copolymer components, as described above. The glass transition temperature (Tg) of the main chain of the acrylic adhesive polymer having a hydroxyl group is not particularly limited, but is preferably within the range of -65°C to -45°C. The glass transition temperature (Tg) is a theoretical value calculated using the Fox equation shown in the following general formula (1) based on the composition of the monomers (monomers) constituting the acrylic adhesive polymer.

[0079] 1 / Tg=W 1 / Tg 1+W 2 / Tg 2+･･･+W n / Tg nGeneral formula (1)

[0080] [In the above general formula (1), Tg is the glass transition temperature of the acrylic adhesive polymer (unit: K), Tg i (i=1, 2, ... n) is the glass transition temperature when monomer i forms a homopolymer (unit: K), and Wi (i=1, 2, ... n) represents the mass fraction of monomer i in all monomer components].

[0081] The glass transition temperature (Tg) of a homopolymer can be determined, for example, from "Polymer Handbook" (edited by J. Brandrup and EH Immergut, Interscience Publishers).

[0082] If the main chain glass transition temperature (Tg) of the acrylic adhesive polymer (copolymer) containing hydroxyl groups is less than -65°C, particularly if the amount of crosslinking agent added (described later) is small, the adhesive layer 2 containing the copolymer may become excessively soft. During cold expansion, the edges (peripheral portions) of the cut die-bonding film may not be partially peeled off from the adhesive layer 2 of the dicing tape 10. Furthermore, during the pickup step after ultraviolet irradiation, the semiconductor wafer with the die-bonding film may be difficult to peel from the adhesive layer 2, or adhesive residue (contamination) may form on the surface of the die-bonding film 3. Consequently, the yield rate of semiconductor wafers with the die-bonding film may decrease.

[0083] On the other hand, when the glass transition temperature (Tg) exceeds -45°C, especially if the amount of cross-linking agent added is large, the adhesive layer 2 containing the cross-linking agent becomes excessively hard, thereby deteriorating the wettability / adhesion to the solid crystal film 3 and the initial adhesion to the solid crystal film 3. Therefore, in the cold expansion step, the solid crystal film 3 is excessively peeled off from the adhesive layer 2, and sufficient external stress cannot be applied to the solid crystal film 3 through the adhesive layer 2, and there is a risk that the solid crystal film 3 cannot be cut neatly, or the incision width cannot be sufficiently ensured, or the incision width may deviate. As a result, the pickup yield of semiconductor chips with solid crystal films is reduced. The glass transition temperature (Tg) is preferably in the range of -63°C or above and -51°C or below, more preferably in the range of -61°C or above and -54°C or below. As such, the glass transition temperature (Tg) is preferably -65°C or above, more preferably -65°C or above. The glass transition temperature (Tg) is preferably -45°C or lower, more preferably -51°C or lower, and particularly preferably -54°C or lower. []

[0084] Examples of the alkyl (meth)acrylate monomer include hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, and octadecyl (meth)acrylate, which have 6 to 18 carbon atoms; and pentyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, ethyl (meth)acrylate, and methyl (meth)acrylate, which have 5 or less carbon atoms. Among these, 2-ethylhexyl acrylate is particularly preferably used, and its content is preferably in the range of 40% by mass or more and 85% by mass or less relative to the total amount of monomer components constituting the main chain of the acrylic adhesive polymer (copolymer) having a hydroxyl group.

[0085] Examples of hydroxyl group-containing monomers 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. The purpose of copolymerizing the above-mentioned hydroxyl monomer is, firstly, to serve as an addition reaction site (-OH) for introducing the later-described active energy ray-reactive carbon-carbon double bond to the above-mentioned acrylic adhesive polymer through an addition reaction; and secondly, to serve as a crosslinking reaction site for reacting the above-mentioned hydroxyl group with the isocyanate group (-NCO) of the later-described polyisocyanate crosslinking agent to increase the molecular weight of the above-mentioned acrylic adhesive polymer and impart cohesive force and appropriate hardness to the adhesive layer 2 before active energy ray irradiation. When utilizing the hydroxyl group of the acrylic adhesive polymer to introduce the active energy ray-reactive carbon-carbon double bond through an addition reaction, as a standard, the content of the above-mentioned hydroxyl monomer is preferably adjusted in advance within a range of, for example, 16.4% by mass or more and 34.4% by mass or less relative to the total amount of the copolymer monomer components. In other words, adjusting the content of the hydroxyl monomer in the copolymer to within the aforementioned range in advance makes it easier to control the constituent elements of the adhesive composition of the present invention, namely, the hydroxyl value of the acrylic adhesive polymer and the equivalent ratio (-NCO / -OH) of the isocyanate group (-NCO) of the polyisocyanate crosslinking agent to the hydroxyl group (-OH) of the acrylic adhesive polymer, which will be described later, to within the aforementioned specific ranges, and is therefore preferred.

[0086] From the perspective of ease of reaction tracking (control stability) and technical difficulty, the most suitable is the acrylic adhesive polymer having an active energy ray-reactive carbon-carbon double bond and a hydroxyl group. This is obtained by copolymerizing the acrylic adhesive polymer having a hydroxyl group and then adding a compound having an isocyanate group and a carbon-carbon double bond (active energy ray-reactive compound) to the hydroxyl group on the side chain of the copolymer. Examples of such compounds having an isocyanate group and a carbon-carbon double bond (active energy ray-reactive compound) include isocyanate compounds having a (meth)acryloyloxy group. Specific examples include 2-methacryloyloxyethyl isocyanate, 4-methacryloyloxy-n-butyl isocyanate, 2-acryloyloxyethyl isocyanate, and m-isopropenyl-α,α-dimethylbenzyl isocyanate.

[0087] The above addition reaction is preferably carried out in the presence of an organometallic catalyst to promote the reaction. Such an organometallic catalyst is preferably at least one selected from an organic compound containing zirconium, an organic compound containing titanium, and an organic compound containing tin. The amount of the organometallic catalyst is not particularly limited, but is generally preferably in the range of 0.01 parts by mass to 5 parts by mass per 100 parts by mass of the acrylic adhesive polymer.

[0088] Furthermore, during the above-mentioned addition reaction, a polymerization inhibitor is preferably used to maintain the reactivity of the carbon-carbon double bond to active energy rays. Such polymerization inhibitors are preferably quinone-based polymerization inhibitors such as hydroquinone / monomethyl ether. The amount of polymerization inhibitor is not particularly limited, but is generally preferably in the range of 0.01 to 0.1 parts by mass relative to 100 parts by mass of the acrylic adhesive polymer.

[0089] During the addition reaction, a desired amount of hydroxyl groups must remain in the adhesive composition in order to crosslink the acrylic adhesive polymer with the subsequently added polyisocyanate crosslinking agent, thereby increasing its molecular weight and imparting cohesive strength and appropriate hardness to the adhesive layer 2 before active energy ray irradiation. Furthermore, the concentration of active energy ray-reactive carbon-carbon double bonds must be controlled within a desired range. These two considerations must be taken into account. For example, when reacting a copolymer having hydroxyl groups in its side chains with an isocyanate compound having (meth)acryloyloxy groups, as a guideline, the addition reaction is preferably performed using an amount of the (meth)acryloyloxy isocyanate compound in a ratio of 37 mol% to 84 mol% relative to the hydroxyl-containing monomer in the acrylic adhesive polymer.

[0090] The acrylic adhesive polymer may also be copolymerized with other copolymerizable monomer components as needed in addition to the (meth)acrylate monomer and the hydroxyl-containing monomer for the purpose of adjusting adhesion, glass transition temperature (Tg), etc. Examples of such other copolymerizable monomer components include carboxyl group-containing monomers such as (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid; anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; amide monomers such as (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-butyl(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, N-methylolpropane(meth)acrylamide, N-methoxymethyl(meth)acrylamide, and N-butoxymethyl(meth)acrylamide; amino group-containing monomers such as aminoethyl(meth)acrylate, N,N-dimethylaminoethyl(meth)acrylate, and t-butylaminoethyl(meth)acrylate; and glycidyl group-containing monomers such as glycidyl(meth)acrylate. The content of the monomer having a functional group is not particularly limited, but is preferably in the range of 0.5% by mass to 30% by mass relative to the total amount of the copolymerized monomer components.

[0091] When copolymerizing monomers having functional groups other than hydroxyl groups, these functional groups can also be utilized to introduce active energy ray-reactive carbon-carbon double bonds into the acrylic adhesive polymer. For example, when the acrylic adhesive polymer has carboxyl groups in its side chains, it can be reacted with active energy ray-reactive compounds such as glycidyl (meth)acrylate or 2-(1-aziridinyl)ethyl (meth)acrylate. When the acrylic adhesive polymer has glycidyl groups in its side chains, it can be reacted with active energy ray-reactive compounds such as (meth)acrylic acid. However, when copolymerizing monomers having functional groups other than hydroxyl groups and utilizing these functional groups to introduce active energy ray-reactive carbon-carbon double bonds into the acrylic adhesive polymer, as a guideline, the content of the co-polymerized hydroxyl monomer is preferably pre-adjusted to a range of, for example, 2.5% by mass to 8.4% by mass relative to the total monomer components of the copolymer. This makes it easy to control the hydroxyl value of the acrylic adhesive polymer and the equivalent ratio (-NCO / -OH) of the isocyanate group (-NCO) of the polyisocyanate crosslinking agent to the hydroxyl group (-OH) of the acrylic adhesive polymer within the above-specified range, which is suitable.

[0092] Furthermore, the acrylic adhesive polymer having the above functional groups may contain other copolymerized monomer components as needed for the purpose of improving cohesion and heat resistance, within a range that does not impair the effects of the present invention. Specific examples of such other copolymerizable monomer components include cyano group-containing monomers such as (meth)acrylonitrile; olefin monomers such as ethylene, propylene, isoprene, butadiene, and isobutylene; styrene monomers such as styrene, α-methylstyrene, and vinyltoluene; vinyl ester monomers such as vinyl acetate and vinyl propionate; vinyl ether monomers such as methyl vinyl ether and ethyl vinyl ether; halogen atom-containing monomers such as vinyl chloride and vinylidene chloride; alkoxy group-containing monomers such as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate; and nitrogen-atom-containing ring monomers such as N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-vinylmorpholine, N-vinylcaprolactam, and N-(meth)acryloylmorpholine. These other copolymerization monomer components may be used alone or in combination of two or more.

[0093] In this embodiment, suitable copolymers having hydroxyl groups for copolymerizing the above-mentioned monomers include, but are not particularly limited to, binary copolymers of 2-ethylhexyl acrylate and 2-hydroxyethyl acrylate, terpolymers of 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, and methacrylic acid, terpolymers of 2-ethylhexyl acrylate, n-butyl acrylate, and 2-hydroxyethyl acrylate, terpolymers of 2-ethylhexyl acrylate, methyl methacrylate, and 2-hydroxyethyl acrylate, tetrapolymers of 2-ethylhexyl acrylate, n-butyl acrylate, 2-hydroxyethyl acrylate, and methacrylic acid, and tetrapolymers of 2-ethylhexyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, and methacrylic acid. Furthermore, it is preferable to add 2-methacryloyloxyethyl isocyanate, an isocyanate compound having a (meth)acryloyloxy group, to these suitable copolymers to form an acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups.

[0094] The acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups obtained in this manner has a hydroxyl value within the range of 12.0 mgKOH / g to 40.5 mgKOH / g. If the hydroxyl value is less than 12.0 mgKOH / g, the hydroxyl value is too low, and crosslinking after the addition of the polyisocyanate crosslinking agent is insufficient. Consequently, the cohesive strength of the adhesive layer 2 before active energy ray irradiation is insufficient, resulting in a risk of adhesive residue on the die-bonding film 3 during pickup, or adhesive residue on the SUS ring frame when the dicing tape 10 is peeled off after the series of steps. Furthermore, the adhesive layer 2 before active energy ray irradiation cannot be given adequate hardness. Therefore, during cold expansion, the edges (peripheral portions) of the cut die-bonding film may not be partially peeled off from the adhesive layer 2 of the dicing tape 10. As a result, the pickup performance is not improved or is reduced compared to the conventional method.

[0095] On the other hand, if the hydroxyl value exceeds 40.5 mgKOH / g, particularly when the amount of polyisocyanate crosslinking agent added is low, the concentration of residual hydroxyl groups in the active energy ray-curable adhesive composition after the crosslinking reaction becomes excessively high, potentially increasing the initial adhesion of the adhesive layer 2 to the die-bonding film 3 beyond necessity. In this case, during cold expansion, the edges (peripheral portions) of the cut die-bonding film may not partially separate from the adhesive layer 2 of the dicing tape 10. Furthermore, during the pickup step after active energy ray irradiation, the semiconductor wafer with the die-bonding film may be difficult to peel from the adhesive layer 2 in the adhesion portion where the adhesive layer 2 and the die-bonding film 3 have not separated due to expansion in the previous step. Consequently, the pickup yield of semiconductor wafers with the die-bonding film may decrease. The hydroxyl value is preferably in the range of 12.5 mgKOH / g to 40.1 mgKOH / g, more preferably in the range of 12.7 mgKOH / g to 30.1 mgKOH / g. Thus, the hydroxyl value is preferably 12.0 mgKOH / g or more, more preferably 12.5 mgKOH / g or more, and particularly preferably 12.7 mgKOH / g or more. Furthermore, the hydroxyl value is preferably 40.5 mgKOH / g or less, more preferably 40.1 mgKOH / g or less, and particularly preferably 30.1 mgKOH / g or less. []

[0096] When the above-mentioned hydroxyl value is in the range of 12.0 mgKOH / g or more and 40.5 mgKOH / g or less, by combining it with the addition of a specific amount of a polyisocyanate-based cross-linking agent described later, the adhesive layer 2 can be given cohesive force, appropriate hardness and polarity, thereby appropriately maintaining the initial adhesion of the adhesive layer 2 to the solid crystal film 3. On the other hand, without hindering the effect of reducing the adhesion of the adhesive layer 2 caused by irradiating the adhesive layer with active energy rays, a moderate peeling state can be formed on the edge portion of the cut solid crystal film 3 from the adhesive layer 2 during the cold expansion step.

[0097] Furthermore, the acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups is not particularly limited, but preferably has an acid value within the range of 0 mgKOH / g to 9.0 mgKOH / g. When the acid value is within this range, the initial adhesion of the adhesive layer 2 to the die-bonding film 3 is appropriately maintained. Furthermore, during the cold expansion step, the edges of the severed die-bonding film 3 are easily peeled from the adhesive layer 2 without hindering the effect of reducing the adhesion of the adhesive layer 2 due to active energy ray irradiation. The acid value is more preferably within the range of 2.0 mgKOH / g to 8.2 mgKOH / g, and even more preferably within the range of 2.5 mgKOH / g to 5.6 mgKOH / g. Thus, the acid value is preferably 0 mgKOH / g or greater, more preferably 2.0 mgKOH / g or greater, and particularly preferably 2.5 mgKOH / g or greater. The acid value is preferably 9.0 mgKOH / g or less, more preferably 8.2 mgKOH / g or less, and particularly preferably 5.6 mgKOH / g or less. []

[0098] Furthermore, the acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups preferably has a weight-average molecular weight (Mw) in the range of 200,000 to 2,000,000. Here, the weight-average molecular weight (Mw) refers to the value measured by gel permeation chromatography in terms of standard polystyrene. If the weight-average molecular weight (Mw) of the acrylic adhesive polymer is less than 200,000, it is difficult to obtain a solution of the active energy ray-curable acrylic adhesive composition with a high viscosity of several thousand to tens of thousands of cP, which is undesirable due to factors such as coating properties. Furthermore, the cohesive force of the adhesive layer 2 before active energy ray irradiation is reduced, and when the semiconductor wafer with the die-bonding film 3 attached is removed from the adhesive layer 2 after active energy ray irradiation, there is a risk of contamination of the die-bonding film surface of the semiconductor wafer. Furthermore, when the dicing tape 10 is peeled off from the SUS ring frame after the completion of the series of steps, there is a risk of adhesive residue on the ring frame.

[0099] On the other hand, if the weight-average molecular weight (Mw) exceeds 2,000,000, it becomes difficult to mass-produce active energy ray-curable acrylic adhesive polymers. For example, during synthesis, the active energy ray-curable acrylic adhesive polymers may gel, resulting in poor quality. Furthermore, if the amount of polyisocyanate crosslinker added is high, the wettability and adhesion of the adhesive layer 2 to the die-bonding film 3 before active energy ray irradiation decreases, reducing initial adhesion. Consequently, during the cold expansion step, the die-bonding film 3 may be excessively peeled from the adhesive layer 2, failing to impart sufficient external stress to the die-bonding film 3 through the adhesive layer 2. This may result in the die-bonding film 3 not being neatly cut, or the incision width not being sufficiently ensured, or the incision width being subject to variation. Consequently, the pickup yield of semiconductor wafers with die-bonding films is reduced. The weight-average molecular weight (Mw) is preferably within the range of 300,000 to 1,000,000.

[0100] [Crosslinking agent] The active energy ray-curable adhesive composition of this embodiment further contains a polyisocyanate crosslinking agent to increase the molecular weight of the acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups by crosslinking, thereby imparting cohesive strength and appropriate hardness to the adhesive layer 2 before active energy ray irradiation. Examples of such polyisocyanate crosslinking agents include polyisocyanate compounds having an isocyanurate ring, adduct polyisocyanate compounds obtained by reacting trimethylolpropane with hexamethylene diisocyanate, adduct polyisocyanate compounds obtained by reacting trimethylolpropane with toluene diisocyanate, adduct polyisocyanate compounds obtained by reacting trimethylolpropane with xylene diisocyanate, and adduct polyisocyanate compounds obtained by reacting trimethylolpropane with isophorone diisocyanate. These can be used alone or in combination of two or more. Among these, from the viewpoint of versatility, an adduct polyisocyanate compound obtained by reacting trimethylolpropane with toluene diisocyanate and / or an adduct polyisocyanate compound obtained by reacting trimethylolpropane with hexamethylene diisocyanate are particularly suitable.

[0101] Commercially available products such as Coronate L-45E, Coronate L-55E, and Coronate L (all trade names) manufactured by Tosoh Corporation or Takenate D101E (trade name) manufactured by Mitsui Chemicals, Inc. may be used as adduct polyisocyanate compounds obtained by reacting trimethylolpropane with toluene diisocyanate. Commercially available products such as Coronate HL (trade name) manufactured by Tosoh Corporation or Takenate D160N (trade name) manufactured by Mitsui Chemicals, Inc. may also be used as adduct polyisocyanate compounds obtained by reacting trimethylolpropane with hexamethylene diisocyanate.

[0102] The polyisocyanate crosslinking agent is contained in an amount within a range of 2.4 parts by mass to 7.0 parts by mass per 100 parts by mass of the acrylic adhesive polymer having an active energy ray-reactive carbon-carbon double bond and a hydroxyl group and a hydroxyl value within a range of 12.0 mgKOH / g to 40.5 mgKOH / g. The equivalent ratio (-NCO / -OH) of the isocyanate group (-NCO) in the polyisocyanate crosslinking agent to the hydroxyl group (-OH) in the acrylic adhesive polymer is adjusted to be within a range of 0.14 to 1.32.

[0103] If the equivalent ratio (-NCO / -OH) is less than 0.14, especially if the hydroxyl value of the acrylic adhesive polymer is low, the adhesive layer 2 before active energy ray irradiation may not be given adequate hardness. Therefore, during cold expansion, the edge portions (peripheral portions) of the cut die-bonding film may not partially peel off from the adhesive layer 2 of the dicing tape 10. As a result, the pickup performance may not be improved compared to conventional methods, or the pickup performance may be reduced. Furthermore, if the hydroxyl value of the acrylic adhesive polymer is high, during cold expansion, the edge portions (peripheral portions) of the cut die-bonding film may not partially peel off from the adhesive layer 2 of the dicing tape 10. Furthermore, the concentration of residual hydroxyl groups after the cross-linking reaction in the active energy ray-curable adhesive composition may become excessively high, potentially increasing the initial adhesion of the adhesive layer 2 to the die-bonding film 3 more than necessary. As a result, in the picking-up step after active energy line irradiation, the semiconductor chip with the solid crystal film attached is not easily peeled off from the adhesive layer 2 in the close contact portion where the adhesive layer 2 and the solid crystal film 3 are not peeled off due to the expansion of the previous step, and the picking-up yield of the semiconductor chip with the solid crystal film is reduced.

[0104] On the other hand, if the equivalent ratio (-NCO / -OH) exceeds 1.32, the adhesive layer 2 becomes excessively hardened before irradiation with the active energy ray, resulting in reduced wettability and adhesion of the adhesive layer 2 to the die-bonding film 3, and a decrease in initial adhesion. Consequently, during the cold expansion step, the die-bonding film 3 peels excessively from the adhesive layer 2, and sufficient external stress cannot be applied to the die-bonding film 3 through the adhesive layer 2. This can lead to problems with neat severing of the die-bonding film 3, insufficient kerf width, or variations in the kerf width. Furthermore, due to the increased rigidity of the adhesive layer 2, the bending modulus of the dicing tape 10 increases. Even when the dicing tape 10 is pushed up by a push-up jig during the pickup step, the dicing tape 10 exhibits minimal bending, potentially hindering the peeling of the four edges of the semiconductor wafer with the die-bonding film from the adhesive layer 2. As a result, the pickup yield of semiconductor wafers with die-bonding films is reduced. Furthermore, the adhesive layer 2 has insufficient adhesion to the SUS ring frame, and there is a risk that the dicing tape 10 may peel off from the SUS ring frame during expansion, preventing the expansion process from proceeding normally.

[0105] Thus, the adhesive layer 2 containing the active energy ray-curable adhesive composition having the adjusted amount of the polyisocyanate crosslinking agent and the adjusted equivalent ratio (-NCO / -OH) exhibits a hardness sufficient to transmit a moderate impact to the interface between the edge of the die-bonding film and the adhesive layer 2 directly below it at the moment the die-bonding film 3 is severed in a low-temperature environment during cold expansion. It also exhibits cohesive strength sufficient to transmit stress away from the die-bonding film 3, and exhibits moderate initial adhesion to the die-bonding film 3. Therefore, the dicing tape 10 having the adhesive layer 2 laminated on the substrate film 1 can be neatly severed by performing a cold expansion step, and the edge portions (the four peripheral portions) of the severed die-bonding film can be appropriately and intentionally partially peeled from the adhesive layer 2 of the dicing tape 10. The equivalent ratio (-NCO / -OH) is preferably within the range of 0.30 or greater and 0.90 or less.

[0106] Here, the equivalent ratio (NCO / OH) of the isocyanate groups (NCO) of the polyisocyanate crosslinking agent to the hydroxyl groups (OH) of the acrylic adhesive polymer is a theoretically calculated value obtained by dividing the total molar number of isocyanate groups obtained by calculating the content of the polyisocyanate crosslinking agent in the active energy ray-curable adhesive composition and the average number of isocyanate groups per molecule of the polyisocyanate crosslinking agent by the total molar number of hydroxyl groups of the acrylic adhesive polymer after active energy ray-reactive carbon-carbon double bonds are introduced. The total molar number of hydroxyl groups is, for example, a value obtained by subtracting the molar number of hydroxyl groups theoretically consumed by a cross-linking reaction with the isocyanate groups of the added isocyanate compound having a (meth)acryloyloxy group (= the molar number of isocyanate groups of the isocyanate compound having a (meth)acryloyloxy group) from the total molar number of hydroxyl groups in the acrylic adhesive polymer having a hydroxyl group, when an addition reaction is carried out using an isocyanate compound having a (meth)acryloyloxy group to introduce active energy ray-reactive carbon-carbon double bonds into the acrylic adhesive polymer having a hydroxyl group, which serves as a base polymer.

[0107] Furthermore, in an active energy ray-curable adhesive composition in which the amount of the polyisocyanate crosslinking agent added and the equivalent ratio (-NCO / -OH) are adjusted to the above ranges, the residual hydroxyl group concentration per gram of the active energy ray-curable adhesive composition after the crosslinking reaction is preferably in the range of 0 mmol to 0.60 mmol. More preferably, it is in the range of 0.02 mmol to 0.40 mmol. Thus, the residual hydroxyl group concentration is preferably 0 mmol or more, more preferably 0.02 mmol or more. Furthermore, the residual hydroxyl group concentration is preferably 0.60 mmol or less, more preferably 0.40 mmol or less. Here, the residual hydroxyl group concentration after the cross-linking reaction per 1 g of the active energy ray-curable adhesive composition refers to the value obtained by subtracting the molar number of hydroxyl groups theoretically consumed by the cross-linking reaction with the isocyanate groups of the added polyisocyanate cross-linking agent (= the molar number of isocyanate groups in the cross-linking agent) from the total molar number of hydroxyl groups possessed by the acrylic adhesive polymer having active energy ray-reactive carbon-carbon double bonds and hydroxyl groups, and then converting the result to per 1 g of the active energy ray-curable adhesive composition.

[0108] If the concentration of residual hydroxyl groups after the cross-linking reaction per gram of the active energy ray-curable adhesive composition is within the above range, the adhesive layer 2 can achieve appropriate initial adhesion to the die-bonding film 3 and adhesion to the SUS ring frame. Therefore, by performing a cold expansion step on the dicing tape 10 having the adhesive layer 2 laminated on the base film 1, the edge portions (the four peripheral portions) of the cut die-bonding film can be easily and intentionally partially peeled from the adhesive layer 2 of the dicing tape 10.

[0109] After forming the adhesive layer 2 using the active energy ray-curable adhesive composition, the aging conditions for reacting the polyisocyanate crosslinking agent with the acrylic adhesive polymer having a hydroxyl group are not particularly limited. For example, the aging conditions may be appropriately set within a temperature range of 23°C to 80°C and a time range of 24 hours to 168 hours.

[0110] [Photopolymerization initiator] The active energy ray-curable adhesive composition of this embodiment contains a photopolymerization initiator that generates free radicals upon exposure to active energy rays. The photopolymerization initiator, upon exposure to active energy rays, generates free radicals, initiating a crosslinking reaction of the carbon-carbon double bonds of the active energy ray-curable acrylic adhesive polymer.

[0111] The photopolymerization initiator is not particularly limited, and conventionally known ones can be used. Specifically, for example, alkylphenone-based photopolymerization initiators, acylphosphine oxide-based photopolymerization initiators, and oxime ester-based photopolymerization initiators can be used. Examples of alkylphenone-based photopolymerization initiators include α-hydroxyalkylphenone-based free radical polymerization initiators, α-hydroxyacetophenone-based free radical polymerization initiators, α-aminoalkylphenone-based free radical polymerization initiators, and benzyl methyl ketal-based free radical polymerization initiators.

[0112] The above-mentioned photopolymerization initiators may be used alone or in combination of two or more as long as they can exert the effects of the present invention. In the active energy ray-curable adhesive composition of this embodiment, among these photopolymerization initiators, from the perspective of effectively reducing both the adhesion force A after ultraviolet irradiation in the presence of oxygen and the adhesion force B after ultraviolet irradiation in the absence of oxygen, the photopolymerization initiator is preferably a photopolymerization initiator comprising at least three systems of an α-aminoalkylphenone-based photopolymerization initiator (a), an alkylphenone-based photopolymerization initiator other than the α-aminoalkylphenone-based photopolymerization initiator (b), and an acylphosphine oxide-based photopolymerization initiator (c).

[0113] In this invention, "adhesion strength A after ultraviolet irradiation in oxygen" refers to the adhesion strength measured when the release liner of the dicing tape 10 is removed, the adhesive layer 2 surface is exposed to air (in oxygen), and ultraviolet rays, acting as active energy rays, are directly irradiated onto the adhesive layer 2 surface, followed by attachment to an adherend (SUS304・BA board). This refers to the portion of the die-bonding film 3 that has been peeled off during expansion when the adhesive layer 2 is exposed to air and ultraviolet rays are irradiated onto the adhesive layer 2. Therefore, this is a model for assuming the adhesion strength of the dicing tape 10 to the die-bonding film 3 when the adhesive layer 2 is exposed to air and the die-bonding film 3 reattaches after ultraviolet irradiation. This indicates the ease of peeling the reattached portion during the pickup step. The lower the adhesion strength, the weaker the reattachment force, making it easier to peel the semiconductor wafer with the die-bonding film from the adhesive layer 2 of the dicing tape 10.

[0114] Furthermore, "Adhesion after UV irradiation in the absence of oxygen B" refers to the adhesion measured after the release liner of the dicing tape 10 is removed and the adhesive layer 2 is attached to an adherend (SUS304・BA board). Ultraviolet rays, acting as active energy rays, are then passed through the base film 1 of the dicing tape 10 and irradiated onto the adhesive layer 2, while the adhesive layer 2 is not exposed to air (in the absence of oxygen). This is a model measure of the adhesion of the dicing tape 10 to the die-bonding film 3 after UV irradiation of the adhesive layer 2, which is not exposed to air, when picking up a semiconductor wafer with a die-bonding film attached. This indicates the ease of peeling off the bonded portion other than the re-adhered portion mentioned above during the pickup step, as the adhesive layer 2 is exposed to UV rays when picking up a semiconductor wafer with a die-bonding film attached. The smaller the adhesive strength value, the easier it is to peel the semiconductor wafer with the die-bonding film from the adhesive layer 2 of the dicing tape 10. The details of the method for measuring the adhesive strength are described below.

[0115] Specific examples of the α-aminoalkylphenone-based photopolymerization initiator (a) include 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one (trade name: Omnirad 907, manufactured by IGM Resins BV), 2-benzylmethyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone (trade name: Omnirad 369, manufactured by IGM Resins BV), and 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one (trade name: Omnirad 379EG, manufactured by IGM Resins BV). These can be used alone or in combination of two or more.

[0116] Among these, the α-aminoalkylphenone-based photopolymerization initiator (a) is preferably 2-benzylmethyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone or 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one.

[0117] The α-aminoalkylphenone-based photopolymerization initiator (a) is particularly effective in reducing the adhesion force A of the adhesive layer 2 after ultraviolet irradiation in the presence of oxygen. However, the adhesion force B of the adhesive layer 2 after ultraviolet irradiation in the absence of oxygen tends to increase with increasing the content of the photopolymerization initiator (a). Therefore, it is preferred to use in combination an alkylphenone-based photopolymerization initiator (b) and an acylphosphine oxide-based photopolymerization initiator (c) other than the α-aminoalkylphenone-based photopolymerization initiator effective for reducing the adhesion force B after ultraviolet irradiation in the absence of oxygen, as described later. The content of the photopolymerization initiator (a) is also preferably within the range described later.

[0118] Examples of the alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator include, as described above, α-hydroxyalkylphenone-based free radical polymerization initiators, α-hydroxyacetophenone-based free radical polymerization initiators, and benzyl methyl ketal-based free radical polymerization initiators. These can be used alone or in combination of two or more.

[0119] Specific examples of the α-hydroxyalkylphenone-based photopolymerization initiator include 1-hydroxycyclohexylphenylketone (trade name: Omnirad 184, manufactured by IGM Resins BV).

[0120] Specific examples of α-hydroxyacetophenone-based photopolymerization initiators include 2-hydroxy-2-methyl-1-phenylpropane-1-one (trade name: Omnirad 1173, manufactured by IGM Resins BV), 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propane-1-one (trade name: Omnirad 2959, manufactured by IGM Resins BV), and 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropane-1-one (trade name: Omnirad 127, manufactured by IGM Resins BV).

[0121] Specific examples of the benzyl methyl ketal-based photopolymerization initiator include 2,2′-dimethoxy-1,2-diphenylethane-1-one (for example, trade name Omnirad 651, manufactured by IGM Resins BV).

[0122] Among these, as the alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropane-1-one, or 2,2'-dimethoxy-1,2-diphenylethane-1-one is particularly preferably used.

[0123] Alkylphenone-based photopolymerization initiators (b) other than the aforementioned α-aminoalkylphenone-based photopolymerization initiator are particularly effective in reducing the adhesion force B of the adhesive layer 2 after ultraviolet irradiation in the absence of oxygen. Furthermore, while their effect on reducing the adhesion force A after ultraviolet irradiation in the presence of oxygen is less than that of the aforementioned α-aminoalkylphenone-based photopolymerization initiator (a), a certain reduction effect can still be achieved depending on the content. Therefore, by using them in combination with the aforementioned α-aminoalkylphenone-based photopolymerization initiator (a), the effect of reducing the adhesion force after ultraviolet irradiation in the presence of oxygen is further enhanced, while also facilitating the reduction of the adhesion force B after ultraviolet irradiation in the absence of oxygen.

[0124] Specific examples of the acylphosphine oxide-based photopolymerization initiator (c) include 2,4,6-trimethylbenzyl-diphenylphosphine oxide (trade name: Omnirad TPO, manufactured by IGM Resins BV), bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (trade name: Omnirad 819, manufactured by IGM Resins BV), and 2,4,6-trimethylbenzyl-diphenylphosphine oxide (trade name: Omnirad TPO, manufactured by IGM Resins BV). These can be used alone or in combination of two or more.

[0125] Among these, bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide is particularly preferably used as the acylphosphine oxide-based photopolymerization initiator (c).

[0126] The acylphosphine oxide-based photopolymerization initiator (c) has an absorption edge extending to wavelengths exceeding 400 nm, resulting in a rapid curing rate. It is particularly effective in further reducing the adhesion force B of the adhesive layer 2 after ultraviolet irradiation in the absence of oxygen. Furthermore, while its effect on reducing the adhesion force A after ultraviolet irradiation in the presence of oxygen is less than that of the α-aminoalkylphenone-based photopolymerization initiator (a), a certain reduction effect can be achieved depending on the content. Therefore, by combining the α-aminoalkylphenone-based photopolymerization initiator (a) with an alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator, the effect of reducing the adhesion force A after ultraviolet irradiation in the presence of oxygen is further enhanced, while also easily improving the effect of reducing the adhesion force B after ultraviolet irradiation in the absence of oxygen.

[0127] Specific examples of suitable combinations of photopolymerization initiators comprising at least three types of photopolymerization initiators, namely, the aforementioned α-aminoalkylphenone-based photopolymerization initiator (a), an alkylphenone-based photopolymerization initiator other than the α-aminoalkylphenone-based photopolymerization initiator (b), and an acylphosphine oxide-based photopolymerization initiator (c), include: (1) A combination of three types: (a) 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butane-1-one, (b) 1-hydroxycyclohexylphenyl ketone, and (c) bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide. (2) A combination of three types of photopolymerization initiator (a): 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butane-1-one / photopolymerization initiator (b): 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropane-1-one / photopolymerization initiator (c): bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide, (3) Photopolymerization initiator (a): 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butane-1-one / Photopolymerization initiator (b): 1-hydroxycyclohexyl phenyl ketone and 2,2'-dimethoxy-1,2-diphenylethane-1-one / Photopolymerization initiator (c): a combination of four types of bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide, (4) Photopolymerization initiator (a): 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butane-1-one / Photopolymerization initiator (b): 1-hydroxycyclohexyl phenyl ketone and 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropane-1-one / Photopolymerization initiator (c): a combination of four kinds of bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide, (5) Photopolymerization initiator (a): 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butane-1-one / photopolymerization initiator (b): 2-hydroxy-1-{4-[4-2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropane-1-one and 2,2'-dimethoxy-1,2-diphenylethane-1-one / photopolymerization initiator (c): a combination of four types of bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide, etc.

[0128] As described above, the active energy ray-curable adhesive composition of the present embodiment is preferably composed of at least three photopolymerization initiators, namely, an α-aminoalkylphenone-based photopolymerization initiator (a), an alkylphenone-based photopolymerization initiator other than the α-aminoalkylphenone-based photopolymerization initiator (b), and an acylphosphine oxide-based photopolymerization initiator (c). In this case, due to the synergistic effect of the functions of the respective photopolymerization initiators, (1) when the adhesive layer 2 is irradiated with ultraviolet rays in an oxygen-free state, the curing of the acrylic adhesive polymer having an active energy ray-reactive carbon-carbon double bond contained in the adhesive composition proceeds sufficiently within a specific time, and (2) even when the adhesive layer 2 is irradiated with ultraviolet rays in an oxygen-containing state, the reduction in curing speed due to the influence of oxygen hindrance is greatly suppressed, making it easy for the acrylic adhesive polymer having an active energy ray-reactive carbon-carbon double bond contained in the adhesive composition to proceed to a desired level within a specific time. As a result, first, (1) when irradiated with ultraviolet rays, the adhesive layer 2 is easily given an adhesion strength B after ultraviolet irradiation in the absence of oxygen, which is within the desired range described later. Furthermore, (2) when irradiated with ultraviolet rays, the adhesive layer 2 is easily given an adhesion strength B after ultraviolet irradiation in the absence of oxygen, which is within the desired range described later. Furthermore, (2) when irradiated with ultraviolet rays, the adhesive layer 2 is easily given an adhesion strength A after ultraviolet irradiation in the presence of oxygen, which is within the desired range described later, which is within the desired range described later, which is within the desired range, as is seen in the conventional dicing tape 10.

[0129] Thus, in the picking-up step, in order to pick up the semiconductor wafer with the bonding film, after irradiating the adhesive layer 2 with ultraviolet rays and then bringing the suction claws into contact from the upper part of the semiconductor wafer, the effect of the edge portion of the bonding film of the semiconductor wafer with the bonding film, which has been partially peeled off from the adhesive layer 2 due to expansion in the previous step, being firmly re-fixed to the insufficiently cured adhesive layer 2 due to oxygen hindrance can be greatly suppressed. That is, the re-fixation force can be weakened to a level that allows easy peeling by pushing from the jig on the lower side of the dicing tape 10. In addition, as for the surfaces of the adhesive layer 2 and the bonding film of the semiconductor wafer with the bonding film without peeling off, a suitable adhesion force B after ultraviolet irradiation in the absence of oxygen can be given. Therefore, the semiconductor wafer with the bonding film can be well picked up from the adhesive layer 2 thereafter.

[0130] The amount of the photopolymerization initiator added (the total amount when two or more are used in combination) is preferably within a range of 1.2 parts by mass to 12.0 parts by mass per 100 parts by mass of the solid content of the active energy ray-curable acrylic adhesive polymer. If the amount of the photopolymerization initiator added is less than 1.2 parts by mass, the photoreactivity to active energy rays is insufficient. Therefore, even with irradiation, the photoradical crosslinking reaction of the acrylic adhesive polymer does not fully occur. As a result, the adhesion-reducing effect of the adhesive layer 2 after ultraviolet irradiation is reduced, both in the presence and absence of oxygen, potentially increasing the probability of semiconductor wafer pickup failure. On the other hand, if the amount of the photopolymerization initiator added exceeds 12.0 parts by mass, the effect is saturated, which is also uneconomical. Furthermore, depending on the type of photopolymerization initiator, the adhesion B of the adhesive layer 2 after ultraviolet irradiation in the absence of oxygen may be greater than desired, increasing the probability of semiconductor wafer pickup failure with a die-bonding film.

[0131] In one preferred embodiment containing three types of photopolymerization initiators, the amounts of the α-aminoalkylphenone-based photopolymerization initiator (a), the alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator, and the acylphosphine oxide-based photopolymerization initiator (c) added are preferably adjusted to be within a range of 0.8 to 5.0 parts by mass for the α-aminoalkylphenone-based photopolymerization initiator (a), within a range of 0.2 to 5.0 parts by mass for the alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator, and within a range of 0.2 to 2.0 parts by mass for the acylphosphine oxide-based photopolymerization initiator (c), relative to 100 parts by mass of the solid content of the active energy ray-curable acrylic adhesive polymer.

[0132] If the amount of the α-aminoalkylphenone-based photopolymerization initiator (a) added is less than 0.8 parts by mass, the adhesive strength A of the adhesive layer 2 after ultraviolet irradiation in the presence of oxygen may not decrease to the desired value. On the other hand, if the amount of the α-aminoalkylphenone-based photopolymerization initiator (a) added exceeds 5.0 parts by mass, the adhesive strength B of the adhesive layer 2 after ultraviolet irradiation in the absence of oxygen may become greater than the desired value. Furthermore, the storage stability of the dicing tape 10 may deteriorate. If the amount of the alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator added is less than 0.2 parts by mass, the adhesive strength of the adhesive layer 2 after ultraviolet irradiation in both the presence of oxygen and the absence of oxygen may not decrease to the desired value. If the amount of the alkylphenone-based photopolymerization initiator (b) other than the α-aminoalkylphenone-based photopolymerization initiator exceeds 5 parts by mass, its effect becomes saturated, which is also uneconomical. Furthermore, the storage stability of the dicing tape 10 may deteriorate. If the amount of the acylphosphine oxide-based photopolymerization initiator (c) is less than 0.2 parts by mass, the adhesion of the adhesive layer 2 after ultraviolet irradiation in the presence and absence of oxygen may not decrease to the desired value. If the amount of the acylphosphine oxide-based photopolymerization initiator (c) exceeds 2 parts by mass, its effect becomes saturated, which is also uneconomical. Furthermore, depending on the amount of the other photopolymerization initiators (a) and (b) added, the storage stability of the dicing tape 10 may deteriorate.

[0133] When the amounts of the α-aminoalkylphenone-based photopolymerization initiator (a), the alkylphenone-based photopolymerization initiator other than the α-aminoalkylphenone-based photopolymerization initiator (b), and the acylphosphine oxide-based photopolymerization initiator (c) are adjusted within the above-mentioned ranges, the adhesive strength of the adhesive layer 2 can be reduced to a desired level by irradiating it with ultraviolet light, regardless of whether it is in the presence of oxygen or in the absence of oxygen, and the semiconductor wafer with the die-bonding film attached can be well picked up by the adhesive layer 2 in the pickup step.

[0134] Furthermore, as a sensitizer for the photopolymerization initiator, compounds such as dimethylaminoethyl methacrylate and isopentyl 4-dimethylaminobenzoate may be added to the active energy ray-curable acrylic adhesive composition within a range that does not impair the effects of the present invention.

[0135] [other] The active energy ray-curable adhesive composition of this embodiment may also contain other additives such as active energy ray-curable compounds (e.g., multifunctional urethane acrylate oligomers), tackifiers, fillers, anti-aging agents, colorants, flame retardants, antistatic agents, surfactants, silane coupling agents, and leveling agents, as needed, without impairing the effects of the present invention.

[0136] [Active energy ray-reactive carbon-carbon double bond concentration] The active energy ray-curable adhesive composition of this embodiment is not particularly limited, but is preferably adjusted so that the active energy ray-reactive carbon-carbon double bond concentration is within a range of 0.85 meq to 1.50 meq per 1 gram of the active energy ray-curable adhesive composition. If the active energy ray-reactive carbon-carbon double bond concentration is less than 0.85 meq per 1 gram of the active energy ray-curable adhesive composition, and if the concentration of residual hydroxyl groups after the cross-linking reaction in the active energy ray-curable adhesive composition per 1 gram is high, the adhesive strength of the adhesive layer 2 after ultraviolet irradiation, particularly the adhesive strength A after ultraviolet irradiation in the presence of oxygen, may not be sufficiently reduced, potentially making it difficult to peel the semiconductor wafer with the die-bonding film from the adhesive layer 2 during the pickup step.

[0137] On the other hand, if the concentration of active energy ray-reactive carbon-carbon double bonds exceeds 1.50 meq per gram of the active energy ray-curable adhesive composition, the effect gradually saturates, which is also uneconomical. Furthermore, depending on the copolymer composition of the acrylic adhesive polymer, gelation during polymerization or reaction can occur, sometimes making synthesis difficult. Furthermore, the carbon-carbon double bond content of the acrylic adhesive polymer can be determined by measuring the iodine value of the acrylic adhesive polymer.

[0138] If the concentration of active energy ray-reactive carbon-carbon double bonds per gram of the active energy ray-curable adhesive composition is within the range of 0.85 meq to 1.50 meq, the adhesive strength of the adhesive layer 2 can be easily reduced to the desired level by ultraviolet irradiation, both in the presence and absence of oxygen, as described above. This facilitates the successful pickup of the semiconductor wafer with the die-bonding film from the adhesive layer 2 during the pickup step. The concentration of active energy ray-reactive carbon-carbon double bonds is more preferably within the range of 0.88 meq to 1.46 meq per gram of the active energy ray-curable adhesive composition. Thus, the concentration of active energy ray-reactive carbon-carbon double bonds per gram of the active energy ray-curable adhesive composition is preferably 0.85 meq or more, more preferably 0.88 meq or more, and is further preferably 1.50 meq or less, more preferably 1.46 meq or less. []

[0139] [Adhesion of adhesive layer] The adhesive layer 2 of the dicing tape 10 exhibits an adhesion strength A of 3.50 N / 25 mm or less to a stainless steel plate (SUS304・BA plate) at 23°C under ultraviolet irradiation. As described above, the adhesion strength A after ultraviolet irradiation under ultraviolet irradiation refers to the adhesion strength of the adhesive layer 2 after ultraviolet irradiation, which takes into account the fact that the adhesive layer 2 will not fully achieve the adhesion reduction effect of ultraviolet irradiation due to polymerization hindrance caused by oxygen in the surrounding air at the edges of the die-bonding film (adhesive layer) 3 that has been severed and peeled. The smaller the adhesion force A after ultraviolet irradiation in the presence of oxygen, the better. However, it is difficult to completely prevent the polymerization inhibition caused by oxygen, and the reduction of the adhesion force has a limit. On the other hand, in a series of steps for obtaining a semiconductor chip with a die-bonding film, of course, it is also necessary to consider the characteristics other than the adhesion force A of the die-bonding film (adhesive layer) 3 of the dicing tape 10 after ultraviolet irradiation in the presence of oxygen. Therefore, in the adhesive layer of the present invention, its lower limit is preferably controlled at 1.25N / 25mm. Furthermore, when the adhesion force A after ultraviolet irradiation in the above-mentioned oxygen atmosphere exceeds 3.50 N / 25 mm, in the pickup step, after the adhesive layer 2 is irradiated with ultraviolet light, when the suction claws for pickup are brought into contact / landed on the surface of the semiconductor wafer with a die-bonding film on the dicing tape 10 on the push-up jig from above, even if the jig is pushed up from the bottom side of the dicing tape 10 and the suction claws are used to suck / pull up, the edge portion of the die-bonding film of the semiconductor wafer with a die-bonding film that has been peeled off from the adhesive layer 2 of the dicing tape 10 will be strongly re-adhered to the insufficiently cured adhesive layer 2 to the extent that the semiconductor wafer with a die-bonding film cannot be easily peeled off from the adhesive layer 2. Even if the push-up jig is used to push up from the bottom side of the dicing tape 10, it is difficult to create an opportunity for peeling from the edge portion, which sometimes hinders the pickup of the semiconductor wafer with a die-bonding film. Furthermore, if the lifting jig is attempted to increase its lifting height (lifting amount) and force the pick-up, the risk of damaging the semiconductor wafer increases. The adhesion force A after ultraviolet irradiation in the presence of oxygen is preferably in the range of 1.30 N / 25 mm to 3.00 N / 25 mm, more preferably 1.35 N / 25 mm to 2.75 N / 25 mm. Thus, the adhesion force A is preferably 1.25 N / 25 mm or more, more preferably 1.30 N / 25 mm or more, and particularly preferably 1.35 N / 25 mm or more. Furthermore, the adhesion force A is preferably 3.50 N / 25 mm or less, more preferably 3.00 N / 25 mm or less, and particularly preferably 2.75 N / 25 mm or less. []

[0140] When the adhesion force A after ultraviolet irradiation in the presence of oxygen is within the range of 3.50 N / 25 mm or less, in the pickup step, after ultraviolet irradiation of the adhesive layer 2, when the suction claws for pickup are brought into contact / landed on the surface of the semiconductor wafer with a die-bonding film on the dicing tape 10 on the push-up jig from above, the phenomenon of the edge portion of the die-bonding film of the semiconductor wafer with a die-bonding film peeled from the adhesive layer 2 of the dicing tape 10 being firmly reattached to the adhesive layer 2 that was insufficiently cured due to the ultraviolet irradiation is significantly suppressed. In other words, the reattachment force is weakened to a level that allows the semiconductor wafer with a die-bonding film to be easily peeled from the adhesive layer 2 by pushing up from the jig on the lower side of the dicing tape 10. When the push-up jig is used from the lower side of the dicing tape 10, an opportunity for peeling from the edge portion is easily created, and the pickup of the semiconductor wafer with a die-bonding film is not hindered. Furthermore, the risk of damaging the semiconductor wafer during pickup is also reduced. As a result, in the pickup step, the semiconductor wafer with the die-bonding film can be picked up well by the adhesive layer 2 after ultraviolet irradiation.

[0141] As described above, in the actual picking-up step, when the edge portion of the bonding film of the semiconductor wafer with the bonding film peeled off from the adhesive layer 2 of the dicing tape 10 is re-bonded to the adhesive layer 2 irradiated with ultraviolet light in the state exposed to air, the re-bonding force is weakened compared to the past. This is presumably due to the following reasons. That is, first, (1) the surface of the adhesive layer 2, whose adhesion force A is reduced to a level of 3.50 N / 25 mm or less after ultraviolet light irradiation in the presence of oxygen, is hardened to the desired level by ultraviolet light irradiation and is given a moderate hardness. Thus, the adhesive layer 2 of this embodiment has significantly suppressed wettability / adhesion to the bonding film 3 compared to the adhesive layer 2 before ultraviolet light irradiation or the conventional adhesive layer after ultraviolet light irradiation whose curing is insufficient due to polymerization hindrance caused by oxygen. On the other hand, (2) when actually picking up a semiconductor wafer with a die-bonding film, the time from the edge of the die-bonding film of the semiconductor wafer with a die-bonding film peeled off from the adhesive layer 2 of the dicing tape 10 to the time of pushing up from the bottom side of the dicing tape 10 by the jig after the semiconductor wafer is reattached to the adhesive layer 2 after ultraviolet irradiation by the suction claw is extremely short. In this way, even if the adhesive force A of the present embodiment after ultraviolet irradiation under oxygen decreases to a level of 3.50 N / 25 mm or less, the edge of the die-bonding film (adhesive layer) peeled off is brought into contact again, and before the two layers are fully attached, the pushing up of the semiconductor wafer with a die-bonding film by the jig from the bottom side of the dicing tape 10 is immediately started, and the process is transferred to picking up. In other words, during reattachment, it is possible to avoid the adhesion between the two layers being maintained at a high value as in the past. Therefore, when the edge portion of the semiconductor chip with a solid film attached is appropriately peeled off from the adhesive layer 2 by the expansion step, combined with the above-mentioned effect of reducing the adhesion A after ultraviolet irradiation under oxygen, it is believed that the force required to initially peel off the edge portion of the semiconductor chip with a solid film is smaller than that of the previous pattern in which the cut solid film (adhesive layer) and the adhesive layer are not peeled off by the expansion step but the two layers are kept in a tightly bonded state from the initial bonding to perform the picking step.

[0142] The adhesion strength (A) after ultraviolet irradiation under oxygen in the present invention is measured using the following method. First, prepare a dicing tape 10 and a stainless steel plate (SUS304・BA plate). Cut the dicing tape 10 into pieces with a width (TD direction of the substrate film 1) of 25 mm and a length (MD direction of the substrate film 1) of 120 mm. Next, irradiate the adhesive layer side of the dicing tape 10, after removing the release liner, with ultraviolet (UV) light of a central wavelength of 367 nm (irradiation intensity: 70 mW / cm², integrated radiation: 150 mJ / cm²) using a metal halide lamp. Then, press-bond the dicing tape 10 from the end of the adhesive layer side to the stainless steel plate (SUS304・BA plate) using a 2 kg rubber roller. The roller is moved back and forth once at a speed of approximately 5 mm / second in an environment of 23°C and 50% RH. The resultant test piece is then pressed and bonded to the surface. After 20 minutes of quiescence, the test piece was subjected to adhesive strength measurement using the peel-angle-free adhesive / film peeling analysis device shown in Figure 4. First, a test piece, with dicing tape 10 attached to a stainless steel plate 4, was secured to the flat cross stage 5 of the adhesive / film peeling analysis device using a dedicated jig. The end of the dicing tape 10 was secured to a force gauge 7 equipped with a clamp (not shown). Next, in an environment of 23°C and 50% relative humidity, as shown in Figure 4 (a schematic diagram of the device viewed from directly above), the actuator 6 moved the rotating stage 8 carrying the flat cross stage 5 at a stage speed V1 of 300 mm / min in the direction opposite to the force gauge 7 (in the direction of arrow V1). Simultaneously, the flat cross stage 5 was moved on the rotating stage 8 at a peel speed V2 of 300 mm / min, synchronized with the stage speed V1, in the direction of a 90° peel angle (in the direction of arrow V2). This method allows the dicing tape 10 to be peeled from a stainless steel plate 4 fixed to a flat cross stage while maintaining a 90° peel angle at a rate of 300 mm / minute. The adhesive layer 2, along with the base film 1, is peeled from the stainless steel plate 4 using a force gauge 7 to measure the load applied during peeling. Using the above method, the adhesion force (unit: N / 25 mm) of the dicing tape 10 at a 90° peel angle to the stainless steel plate (SUS304・BA plate) 4 was measured. The measurement was performed on three test pieces, and the average of the values ​​from the three test pieces was used as the adhesion force A of the dicing tape 10 after ultraviolet irradiation in the presence of oxygen.

[0143] Furthermore, the adhesive layer 2 of the dicing tape 10 has an adhesion strength (B) of 0.25 N / 25 mm to a stainless steel plate (SUS304 BA plate) at 23°C after ultraviolet irradiation in the absence of oxygen. The adhesion strength (B) after ultraviolet irradiation in the absence of oxygen refers to the adhesion strength between the adhesive layer 2 and the adherend (die-bonding film 3) after ultraviolet irradiation (the surface in close contact without peeling), ignoring the effects of oxygen hindrance caused by ambient oxygen. From the perspective of improving pickup performance, the adhesion strength (B) after ultraviolet irradiation is preferably as low as possible within the above range. However, if it is less than 0.25 N / 25 mm, the semiconductor wafer with the die-bonding film attached may unintentionally fall off the adhesive layer 2 of the dicing tape 10 or become displaced before pickup. Furthermore, if the adhesion force B after ultraviolet irradiation in the absence of oxygen is greater than 0.70 N / 25 mm, even if a push-up jig is used to push up from the bottom side of the dicing tape 10 during the pickup step, the peeling of the die-bonding film 3a from the adhesive layer 2 toward the center, following the peeling of the edge portion of the die-bonding film 3a, will not proceed smoothly, making pickup difficult. Furthermore, if the push-up jig is used to increase the lifting height (lifting amount) and force pickup, there is a risk of damaging the semiconductor wafer. The adhesion force B after ultraviolet irradiation in the absence of oxygen is preferably in the range of 0.30 N / 25 mm to 0.65 N / 25 mm, more preferably in the range of 0.35 N / 25 mm to 0.60 N / 25 mm. Therefore, the adhesion force B is preferably 0.25 N / 25 mm or more, more preferably 0.30 N / 25 mm or more, and particularly preferably 0.35 N / 25 mm or more. Furthermore, the adhesive force B is preferably 0.70 N / 25 mm or less, more preferably 0.65 N / 25 mm or less, and particularly preferably 0.60 N / 25 mm or less. []

[0144] When the adhesion strength B after UV irradiation in the absence of oxygen is within the range of 0.25 N / 25 mm to 0.70 N / 25 mm, the pick-up process facilitates the peeling of the die-bonding film from the adhesive layer 2 from the outer periphery toward the center of the contact surface between the die-bonding film and the adhesive layer 2 of the semiconductor wafer with the die-bonding film, when the dicing tape 10 is lifted from the bottom side using a lifting jig. This improves pick-up performance. Furthermore, the risk of damage to the semiconductor wafer during pickup is reduced.

[0145] The adhesion strength (B) after ultraviolet irradiation in the absence of oxygen in the present invention is measured using the following method. First, separate dicing tapes 10 and stainless steel plates (SUS304·BA plates) are prepared. The dicing tape 10 is cut into pieces with a width (TD direction of the substrate film 1) of 25 mm and a length (MD direction of the substrate film 1) of 120 mm. Next, a 2 kg rubber roller is applied to the stainless steel plate (SUS304·BA plate) from the end of the adhesive layer 2 of the dicing tape 10, from which the release liner has been removed, at a speed of approximately 5 mm / second, to press and bond the pieces together. After allowing the pieces to stand for 20 minutes, ultraviolet (UV) rays with a central wavelength of 367 nm (irradiation intensity: 70 mW / cm², integrated radiation: 150 mJ / cm²) are applied from the substrate film 1 side of the dicing tape 10 using a metal halide lamp to prepare test pieces for measurement. For this test piece, similar to the measurement of adhesion strength (A) after UV irradiation in the presence of oxygen, the adhesion strength (unit: N / 25mm) of the dicing tape 10 at a 90° peel angle relative to a stainless steel plate (SUS304・BA plate) was measured using the peel angle-free adhesive / film peeling analyzer shown in Figure 4. The measurement was performed on three test pieces, and the average of the three values ​​was used as the adhesion strength (B) of the dicing tape 10 after UV irradiation in the absence of oxygen.

[0146] The ratio A / B of the adhesion force A of the adhesive layer 2 of the dicing tape 10 after ultraviolet irradiation in the absence of oxygen to the adhesion force B after ultraviolet irradiation in the presence of oxygen can be calculated to evaluate the effect of polymerization inhibition caused by oxygen in the adhesive layer.

[0147] In the dicing tape 10 of this embodiment, the ratio (A / B) of the adhesion force A after ultraviolet irradiation under aerobic conditions to the adhesion force B after ultraviolet irradiation under anoxic conditions is not particularly limited within a range that does not impair the effects of the present invention, but is preferably within a range of 3.00 to 5.00. If the ratio (A / B) of the adhesion force A after ultraviolet irradiation under aerobic conditions to the adhesion force B after ultraviolet irradiation under anoxic conditions is within the above range, the adhesive layer 2 formed by the expansion step of the dicing tape 10 can be further prevented from insufficiently reducing the adhesion force due to polymerization hindrance caused by oxygen contained in the surrounding air during ultraviolet irradiation, thereby maintaining a high adhesion value. In other words, the re-anchoring force can be further weakened to a level that allows for easier peeling by pushing on a jig from the bottom side of the dicing tape 10. As a result, when the push-up jig is used to push up from the bottom side of the dicing tape 10, it is easier to create an opportunity for peeling from the edge portion, which can make the force required to peel off the edge portion of the semiconductor chip with the initial bonding film smaller, so that the semiconductor chip with the bonding film can be picked up better from the adhesive layer 2 after ultraviolet irradiation.

[0148] [Thickness of adhesive layer] The thickness of the adhesive layer 2 of this embodiment is not particularly limited, but is preferably in the range of 3 μm or more and 30 μm or less, more preferably in the range of 5 μm or more and 20 μm or less, and particularly preferably in the range of 8 μm or more and 15 μm or less. Thus, the thickness is preferably 3 μm or more, more preferably 5 μm or more, and particularly preferably 8 μm or more. Furthermore, the thickness is preferably 30 μm or less, more preferably 20 μm or less, and particularly preferably 15 μm or less. When the thickness of the adhesive layer 2 is less than 3 μm, especially when the amount of polyisocyanate crosslinking agent added is large, there is a risk that the adhesion of the dicing tape 10 will be excessively reduced. In this case, there is a risk that the adhesion to the SUS ring frame will be insufficient, and during the cold expansion step, the dicing tape 10 may be peeled off from the SUS ring frame, making it impossible to perform the normal expansion step. In addition, when used as a dicing die-bonding film, poor adhesion between the adhesive layer 2 and the die-bonding film 3 may sometimes occur. On the other hand, if the thickness of the adhesive layer 2 exceeds 30 μm, particularly if a large amount of polyisocyanate crosslinking agent is added, the die-bonding film 3 may peel excessively from the adhesive layer 2 during cold expansion of the dicing tape 10. This may result in insufficient external stress being applied to the die-bonding film 3 through the adhesive layer 2, leading to the risk of not being able to neatly cut the die-bonding film 3, or the incision width being insufficiently maintained or the incision width being uneven. This may increase the likelihood of pickup failures of semiconductor wafers with the die-bonding film attached. Furthermore, this is not practically desirable from an economical perspective.

[0149] (Anchor Coating) In the dicing tape 10 of this embodiment, an anchor coating layer that matches the composition of the base film 1 can be provided between the base film 1 and the adhesive layer 2, depending on the manufacturing conditions of the dicing tape 10 or the usage conditions of the dicing tape 10 after manufacturing, without impairing the effects of the present invention. The provision of the anchor coating layer improves the adhesion between the base film 1 and the adhesive layer 2.

[0150] (Release liner) A release liner may be provided on the surface of the adhesive layer 2 opposite to the substrate film 1 (one surface), as needed. The release liner is not particularly limited; examples include synthetic resins such as polyethylene, polypropylene, and polyethylene terephthalate, and paper. Furthermore, to enhance the releasability of the adhesive layer 2, the surface of the release liner may be treated with a release agent such as a silicone release agent, a long-chain alkyl release agent, or a fluorine release agent. The thickness of the release liner is not particularly limited; however, a thickness between 10 μm and 200 μm is suitable.

[0151] (Method for manufacturing dicing tape) Figure 5 is a flow chart illustrating a method for manufacturing dicing tape 10. First, a release liner is prepared (step S101: release liner preparation step). Next, a coating solution for the adhesive layer 2 (adhesive layer-forming coating solution) is prepared (step S102: coating solution preparation step). The coating solution can be prepared by, for example, uniformly mixing and stirring an acrylic adhesive polymer, which constitutes the adhesive layer 2, a crosslinking agent, and a diluent solvent. The solvent can be a general-purpose organic solvent such as toluene or ethyl acetate.

[0152] Then, using the coating solution for the adhesive layer 2 prepared in step S102, the coating solution is applied to the release-treated surface of the release liner and dried to form an adhesive layer 2 of a specific thickness (step S103: adhesive layer forming step). The coating method is not particularly limited, and for example, a die coater, a notch wheel coater (registered trademark), a gravure coater, a roller coater, a reverse roller coater, etc. can be used for coating. In addition, the drying conditions are not particularly limited, and for example, it is preferably carried out at a drying temperature within the range of 80°C to 150°C and a drying time within the range of 0.5 minutes to 5 minutes. Next, prepare the substrate film 1 (step S104: substrate film preparation step). Then, the substrate film 1 is laminated on the adhesive layer 2 formed on the release liner (step S105: substrate film laminating step). Finally, the formed adhesive layer 2 is aged at 40°C for 72 hours, for example, to allow the acrylic adhesive polymer to react with the crosslinking agent, thereby crosslinking and curing (step S106: thermal curing step). Through the above steps, a dicing tape 10 is produced, comprising an adhesive layer 2 and a release liner on a substrate film 1, in this order, from the substrate film side. In the present invention, a laminate having a release liner on an adhesive layer 2 is sometimes referred to as a dicing tape 10.

[0153] Furthermore, as a method for forming the adhesive layer 2 on the substrate film 1, a method is described in which a coating solution for the adhesive layer 2 is applied onto a release liner and dried, followed by laminating the substrate film 1 onto the adhesive layer 2. However, a method in which the coating solution for the adhesive layer 2 is directly applied onto the substrate film 1 and dried can also be used. From the perspective of stable production, the former method is more suitable.

[0154] The dicing tape 10 of this embodiment can also be wound into a roll or laminated with a wide sheet. In addition, the dicing tape 10 can be pre-cut into a sheet or tape of a specific size.

[0155] <Cutting Die Bonding Film> The dicing tape 10 of this embodiment can also be used in the semiconductor manufacturing process as a dicing tape 20 in which a bonding film (adhesive layer) 3 is adhered to the adhesive layer 2 of the dicing tape 10 to form a removable dicing bonding film. The bonding film (adhesive layer) 3 is used to bond / connect the singulated semiconductor wafers to the lead frame or wiring substrate (support substrate). Furthermore, when laminating semiconductor wafers, it also acts as an adhesive layer between the semiconductor wafers. In this case, the first semiconductor wafer is bonded to the semiconductor wafer mounting wiring substrate with terminals formed thereon via the bonding film (adhesive layer) 3. The second semiconductor wafer is further bonded to the first semiconductor wafer via the bonding film (adhesive layer) 3. The connection terminals of the first-stage semiconductor wafer and the second-stage semiconductor wafer are electrically connected to external connection terminals via wires. The wires for the first-stage semiconductor wafer are embedded in the die-bonding film (adhesive layer) 3 during compression bonding (die bonding), i.e., the aforementioned wire-embedded die-bonding film (adhesive layer) 3. The following describes an example of the die-bonding film (adhesive layer) 3 when the dicing tape 10 of this embodiment is used as a dicing die-bonding film 20, but the present invention is not particularly limited to this example.

[0156] (Die Bonding Film) The die-bonding film (adhesive layer) 3 is a layer composed of a thermosetting adhesive composition that cures by heat. The adhesive composition is not particularly limited, and conventionally known materials can be used. A preferred example of the adhesive composition is a thermosetting adhesive composition comprising a thermoplastic resin containing a glycidyl group-containing (meth)acrylate copolymer, a thermosetting resin containing an epoxy resin, and a phenolic resin serving as a hardener for the epoxy resin, to which a curing accelerator, an inorganic filler, a silane coupling agent, and the like are added. The die-bonding film (adhesive layer) 3 composed of such a thermosetting adhesive composition is preferably characterized by excellent adhesion between the semiconductor chip / support substrate and between the semiconductor chip and semiconductor chip, and can also provide electrode embedding properties and / or line embedding properties, and can be bonded at low temperatures during the die bonding step, can be cured in a short time, and has excellent reliability after being molded with a sealant.

[0157] General-purpose bonding films, used without wires embedded in the adhesive layer, and wire-embedded bonding films, used with wires embedded in the adhesive layer, often share similar materials in terms of the types of materials that make up the adhesive composition. By varying the material blend ratios and the physical properties of the individual materials, the films can be customized for either general-purpose or wire-embedded bonding films, depending on their intended purpose. Furthermore, wire-embedded bonding films are sometimes used as general-purpose bonding films when the reliability of the final semiconductor device is not an issue. In other words, wire-embedded bonding films are not limited to wire-embedded applications; they can also be used to bond semiconductor chips to metal substrates, such as substrates and lead frames, that have uneven surfaces due to wiring.

[0158] (General-purpose adhesive composition for die-bonding films) First, an example of an adhesive composition for a general-purpose die-bonding film will be described, but the invention is not particularly limited to this example. As an indicator of the fluidity of the die-bonding film 3 formed from the adhesive composition during die bonding, for example, the shear viscosity at 80°C can be cited. For general-purpose die-bonding films, the shear viscosity at 80°C generally exhibits a value between 20,000 Pa·s and 40,000 Pa·s, preferably between 25,000 Pa·s and 35,000 Pa·s. Thus, the shear viscosity is preferably 20,000 Pa·s or higher, more preferably 25,000 Pa·s or higher. Furthermore, the shear viscosity is preferably 40,000 Pa·s or lower, more preferably 35,000 Pa·s or lower. An example of a preferred embodiment of the adhesive composition for a general-purpose die-bonding film, based on 100 parts by mass of the total amount of the resin components of the adhesive composition, namely, the glycidyl-containing (meth)acrylate copolymer, the epoxy resin, and the phenol resin, can include: (a) an adhesive composition containing 52 parts by mass to 90 parts by mass of the glycidyl-containing (meth)acrylate copolymer, 5 parts by mass to 25 parts by mass of the epoxy resin, and 5 parts by mass to 23 parts by mass of the phenol resin, with the total amount of the resin components adjusted to 100 parts by mass; (b) an adhesive composition containing 0.1 parts by mass to 0.3 parts by mass of a curing accelerator based on 100 parts by mass of the total amount of the epoxy resin and the phenol resin; and (c) an adhesive composition containing 5 parts by mass to 20 parts by mass of an inorganic filler based on 100 parts by mass of the glycidyl-containing (meth)acrylate copolymer, the epoxy resin, and the phenol resin.

[0159] [Glycidyl-containing (meth)acrylate copolymer] The glycidyl group-containing (meth)acrylate copolymer preferably contains at least an alkyl (meth)acrylate having an alkyl group with 1 to 8 carbon atoms and glycidyl (meth)acrylate as copolymer units. To ensure adequate adhesion, the glycidyl (meth)acrylate copolymer units preferably comprise a range of 0.5% to 6.0% by mass, and more preferably a range of 2.0% to 4.0% by mass, based on the total amount of the glycidyl group-containing (meth)acrylate copolymer. Thus, the glycidyl (meth)acrylate copolymer units preferably comprise 0.5% to 2.0% by mass, and more preferably 6.0% to 4.0% by mass, based on the total amount of the (meth)acrylate copolymer. Furthermore, the glycidyl (meth)acrylate copolymer may, if necessary, contain other monomers such as styrene or acrylonitrile as copolymer units to adjust the glass transition temperature (Tg).

[0160] The glass transition temperature (Tg) of the glycidyl group-containing (meth)acrylate copolymer is preferably in the range of -50°C to 30°C. From the perspective of improving the handleability of the die-bonding film (suppressing adhesion), it is more preferably in the range of -10°C to 30°C. To achieve such a high glass transition temperature of the glycidyl group-containing (meth)acrylate copolymer, ethyl (meth)acrylate and / or butyl (meth)acrylate are preferably used as the alkyl (meth)acrylate having an alkyl group with 1 to 8 carbon atoms.

[0161] The weight-average molecular weight (Mw) of the glycidyl group-containing (meth)acrylate copolymer is preferably in the range of 500,000 to 2,000,000, more preferably 700,000 to 1,000,000. Thus, the Mw is preferably 500,000 or more, more preferably 700,000 or more. Furthermore, the Mw is preferably 2,000,000 or less, more preferably 1,000,000 or less. When the weight-average molecular weight (Mw) falls within the above range, it is easier to achieve appropriate adhesion, heat resistance, and flowability. Here, the weight-average molecular weight (Mw) refers to the standard polystyrene equivalent value measured by gel permeation chromatography.

[0162] The content of the glycidyl group-containing (meth)acrylate copolymer in the die-bonding film (adhesive layer) 3 is preferably 52% by mass or more and 90% by mass or less, more preferably 60% by mass or more and 80% by mass or less, based on 100 parts by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer, the epoxy resin, and the phenol resin described below, as the resin components of the adhesive composition. Thus, the content is preferably 52% by mass or more, more preferably 60% by mass or more. Furthermore, the content is preferably 90% by mass or less, more preferably 80% by mass or less. []

[0163] [Epoxy resin] Epoxy resins are not particularly limited. Examples include bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol S epoxy resins, alicyclic epoxy resins, aliphatic chain epoxy resins, phenol novolac epoxy resins, alkylphenol novolac epoxy resins, cresol novolac epoxy resins, bisphenol A novolac epoxy resins, diglycidyl ethers of biphenols, diglycidyl ethers of naphthalene diols, diglycidyl ethers of phenols, diglycidyl ethers of alcohols, and bifunctional epoxy resins such as alkyl-substituted, halide-, or hydride-substituted versions of these, and novolac-type epoxy resins. Furthermore, other generally known epoxy resins such as multifunctional epoxy resins and heterocyclic epoxy resins may also be used. These may be used alone or in combination of two or more.

[0164] The softening point of the epoxy resin is preferably in the range of 70°C to 130°C from the viewpoint of adhesion and heat resistance. Furthermore, the epoxy equivalent of the epoxy resin is preferably in the range of 100 to 300 from the viewpoint of sufficient curing reaction with the phenolic resin described below.

[0165] The epoxy resin content in the die-bonding film (adhesive layer) 3 is preferably 5% by mass or more and 25% by mass or less, more preferably 10% by mass or more and 20% by mass or less, based on 100 parts by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer, the epoxy resin, and the phenolic resin described below as the resin component of the adhesive composition, in order to properly exhibit its function as a thermosetting adhesive in the die-bonding film (adhesive layer) 3. Thus, the content is preferably 5% by mass or more, more preferably 10% by mass or more. Furthermore, the content is preferably 25% by mass or less, more preferably 20% by mass or less. []

[0166] [Phenolic resin: hardener for epoxy resin] The epoxy resin hardener is not particularly limited. Examples include phenolic resins obtained by reacting a phenolic compound with a divalent linking group-xylyl compound in the absence of a catalyst or in the presence of an acid catalyst. Examples of such phenolic resins include novolac-type phenolic resins, resol-type phenolic resins, and polyoxystyrenes such as polyparaoxystyrene. Examples of novolac-type phenolic resins include phenol novolac resins, phenol aralkyl resins, cresol novolac resins, tert-butylphenol novolac resins, and nonylphenol novolac resins. These phenolic resins can be used alone or in combination of two or more. Among these phenolic resins, phenol novolac resins and phenol aralkyl resins are particularly suitable because they tend to improve the connection reliability of the die-bonding film (adhesive layer) 3.

[0167] The softening point of the phenolic resin is preferably in the range of 70°C to 90°C from the viewpoint of adhesion and heat resistance. Furthermore, the hydroxyl equivalent of the phenolic resin is preferably in the range of 100 to 200 from the viewpoint of sufficient curing reaction with the epoxy resin.

[0168] To ensure sufficient curing reaction between the epoxy resin and the phenol resin in the thermosetting resin composition, the phenol resin is preferably incorporated in an amount such that the total hydroxyl group content of the phenol resin components is preferably within a range of 0.5 to 2.0 equivalents, more preferably 0.8 to 1.2 equivalents, per 1 equivalent of epoxy groups in the total epoxy resin components. Thus, the hydroxyl group content is preferably 0.5 to 0.8 equivalents, more preferably 2.0 to 1.2 equivalents. Since this amount depends on the functional group equivalent weight of each resin, it is difficult to generalize. However, for example, based on 100 parts by mass of the combined amount of the glycidyl-containing (meth)acrylate copolymer, the epoxy resin, and the phenol resin in the resin components of the adhesive composition, the phenol resin content is preferably within a range of 5 to 23 mass%.

[0169] [Hardening accelerator] Furthermore, a curing accelerator such as a tertiary amine, imidazole, or quaternary ammonium salt may be added to the thermosetting resin composition as needed. Specific examples of such curing accelerators include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-cyanoethyl-2-phenylimidazolium trimellitate. These can be used alone or in combination of two or more. The amount of the curing accelerator added is preferably in the range of 0.1 to 0.3 parts by mass per 100 parts by mass of the epoxy resin and the phenolic resin combined.

[0170] [Inorganic fillers] Furthermore, inorganic fillers may be added to the thermosetting resin composition as needed to control the fluidity of the die-bonding film (adhesive layer) 3 and increase its elastic modulus. Examples of such 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. These fillers may be used singly or in combination. Among these, crystalline silica and amorphous silica are particularly suitable for their versatility. Specifically, Aerosil (registered trademark: ultrafine dry silica) with an average particle size of nanometers is suitable. The content ratio of the above-mentioned inorganic filler in the above-mentioned solid crystal film (adhesive layer) 3 is preferably in the range of 5% by mass or more and 20% by mass or less when the total amount of the glycidyl-containing (meth)acrylate copolymer, epoxy resin and phenol resin of the above-mentioned resin components is 100 parts by mass.

[0171] [Silane coupling agent] Furthermore, a silane coupling agent may be added to the thermosetting resin composition as needed to improve adhesion to an adherend. Examples of such silane coupling agents include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane. These may be used singly or in combination. The amount of the silane coupling agent added is preferably in the range of 1.0 to 7.0 parts by mass based on 100 parts by mass of the epoxy resin and the phenolic resin combined.

[0172] [other] Furthermore, the thermosetting resin composition may contain a flame retardant or ion scavenger, as long as the function as a die-bonding film is not impaired. Examples of flame retardants include antimony trioxide, antimony pentoxide, and brominated epoxy resins. Examples of ion scavengers include hydrotalcites, bismuth hydroxide, antimony hydroxide-containing compounds, zirconium phosphates with specific structures, magnesium silicate, aluminum silicate, triazole compounds, tetrazole compounds, and bipyridyl compounds.

[0173] (Adhesive composition for wire-embedded die-bonding films) Next, an example of an adhesive composition for a wire-embedded die-bonding film will be described, but the invention is not particularly limited to this example. As an indicator of the fluidity of the die-bonding film 3 formed from the adhesive composition during die bonding, for example, the shear viscosity at 80°C can be cited. For wire-embedded die-bonding films, the shear viscosity at 80°C generally exhibits a value between 200 Pa·s and 11,000 Pa·s, preferably between 2,000 Pa·s and 7,000 Pa·s. Thus, the shear viscosity is preferably 200 Pa·s or higher, more preferably 2,000 Pa·s or higher. Furthermore, the shear viscosity is preferably 11,000 Pa·s or lower, more preferably 7,000 Pa·s or lower. As an example of a preferred embodiment of the adhesive composition for the wire-embedded die-bonding film, based on 100 parts by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer, the epoxy resin, and the phenol resin in the resin components of the adhesive composition, (a) a composition containing 17 parts by mass or more and 51 parts by mass or less of the glycidyl group-containing (meth)acrylate copolymer, 30 parts by mass or more and 64 parts by mass or less of the epoxy resin, and 19 parts by mass or less of the phenol resin can be cited. (a) an adhesive composition comprising: (i) an epoxy resin containing at least 0.01 parts by mass and at most 0.07 parts by mass of a curing accelerator relative to 100 parts by mass of the total amount of the epoxy resin and the phenol resin; and (ii) an adhesive composition comprising at least 10 parts by mass and at most 80 parts by mass of an inorganic filler relative to 100 parts by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer, the epoxy resin, and the phenol resin.

[0174] [Glycidyl-containing (meth)acrylate copolymer] The glycidyl group-containing (meth)acrylate copolymer preferably contains at least an alkyl (meth)acrylate having an alkyl group with 1 to 8 carbon atoms and glycidyl (meth)acrylate as copolymer units. For wire-embedded die bonding films, it is necessary to achieve a balance between improved fluidity during die bonding and guaranteed bond strength after curing. Therefore, it is preferable to use a glycidyl group-containing (meth)acrylate copolymer (A) having a high copolymer unit ratio of glycidyl (meth)acrylate and a low molecular weight, and a glycidyl group-containing (meth)acrylate copolymer (B) having a low copolymer unit ratio of glycidyl (meth)acrylate and a high molecular weight. Preferably, the former contains a certain amount or more of component (A).

[0175] Specifically, the glycidyl group-containing (meth)acrylate copolymer in the wire-embedded die-bonding film adhesive composition is preferably composed of a mixture of the following (A) and (B): "a copolymer unit of glycidyl (meth)acrylate is contained in an amount of 5.0% by mass or more and 15.0% by mass or less of the total amount of the glycidyl group-containing (meth)acrylate copolymer, a glass transition temperature (Tg) in the range of -50°C or more and 30°C or less, and a weight average molecular weight Mw of 100,000 or more; The invention further comprises a glycidyl group-containing (meth)acrylate copolymer (A) comprising a copolymer unit of glycidyl (meth)acrylate in an amount of from 1.0% to 7.0% by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer, having a glass transition temperature (Tg) of from -50°C to 30°C, and a weight-average molecular weight (Mw) of from 500,000 to 900,000. The weight-average molecular weight (Mw) herein refers to the standard polystyrene equivalent value measured by gel permeation chromatography.

[0176] The content of the glycidyl group-containing (meth)acrylate copolymer (A) is preferably in the range of 60% to 90% by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer (the sum of (A) and (B)). Furthermore, the glycidyl group-containing (meth)acrylate copolymer may, if necessary, contain other monomers such as styrene or acrylonitrile as copolymer units from the perspective of adjusting the glass transition temperature (Tg).

[0177] The glass transition temperature (Tg) of the glycidyl group-containing (meth)acrylate copolymer as a whole is preferably in the range of -50°C to 30°C. From the perspective of improving the handleability (suppressing tackiness) of the die-bonding film, it is more preferably in the range of -10°C to 30°C. To achieve such a glass transition temperature for the glycidyl group-containing (meth)acrylate copolymer, ethyl (meth)acrylate and / or butyl (meth)acrylate are preferably used as the alkyl (meth)acrylate having an alkyl group with 1 to 8 carbon atoms.

[0178] The total content of the glycidyl group-containing (meth)acrylate copolymer (the sum of (A) and (B)) in the wire-embedded die bonding film (adhesive layer) 3 is preferably 17% by mass or more and 51% by mass or less, and more preferably 20% by mass or more and 45% by mass or less, based on 100 parts by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer, the epoxy resin, and the phenol resin described below, as the resin components of the adhesive composition, from the perspective of fluidity during die bonding and adhesive strength after curing. Thus, the content is preferably 17% by mass or more, and more preferably 20% by mass or more. Furthermore, the content is preferably 51% by mass or less, and more preferably 45% by mass or less. []

[0179] [Epoxy resin] The epoxy resin is not particularly limited; the same epoxy resins as those exemplified for the adhesive composition for general-purpose die-bonding films can be used. These epoxy resins may be used alone or in combination of two or more. For wire-embedding die-bonding films, it is necessary to ensure bond strength while preventing voids from forming on the bonding surface and providing good embedding properties for the wires. Therefore, it is preferable to use a combination of two or more epoxy resins to control their fluidity and elastic modulus.

[0180] A preferred embodiment of the epoxy resin used in the wire-embedded die-bonding film (adhesive layer) 3 includes a mixture of an epoxy resin (C) that is liquid at room temperature and an epoxy resin (D) that has a softening point of 98°C or less, preferably 85°C or less. The content of the epoxy resin (C) that is liquid at room temperature is preferably in the range of 15% to 75% by mass, more preferably 30% to 50% by mass, of the total amount of epoxy resin (the sum of (C) and (D)). Thus, the content is preferably 15% to 30% by mass, more preferably 75% to 50% by mass. The epoxy equivalent of the epoxy resin is preferably in the range of 100 to 300 to ensure a sufficient curing reaction with the phenolic resin described below.

[0181] The epoxy resin content in the die-bonding film (adhesive layer) 3 is preferably 30% by mass or more and 64% by mass or less, and more preferably 35% by mass or more and 50% by mass or less, based on 100 parts by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer, the epoxy resin, and the phenolic resin described below, as the resin components of the adhesive composition, in order to properly exhibit its function as a thermosetting adhesive in the die-bonding film (adhesive layer) 3. Thus, the content is preferably 30% by mass or more, and more preferably 35% by mass or more. Furthermore, the content is preferably 64% by mass or less, and more preferably 50% by mass or less. []

[0182] [Phenolic resin: hardener for epoxy resin] The epoxy resin hardener is not particularly limited; the same phenol resins as those exemplified for the general-purpose die-bonding film adhesive composition can be used. The softening point of the phenol resin is preferably between 70°C and 115°C from the perspectives of adhesion and fluidity. Furthermore, the hydroxyl equivalent of the phenol resin is preferably between 100 and 200 to ensure a sufficient curing reaction with the epoxy resin.

[0183] To ensure sufficient curing reaction between the epoxy resin and the phenol resin in the thermosetting resin composition, the phenol resin is preferably blended in an amount such that the total hydroxyl group content of the phenol resin components is preferably 0.5 equivalents to 2.0 equivalents per 1 equivalent of epoxy groups in the total epoxy resin components. To ensure fluidity during die bonding, the amount is preferably 0.6 equivalents to 1.0 equivalents. Thus, the amount of hydroxyl groups in the total phenol resin components is preferably 0.5 equivalents or more, more preferably 0.6 equivalents or more, and preferably 2.0 equivalents or less, more preferably 1.0 equivalents or less. Since it depends on the functional group equivalent weight of each resin, it cannot be generalized. However, for example, the content ratio of the phenolic resin is preferably in the range of 19% by mass or more and 53% by mass or less, based on 100 parts by mass of the total amount of the glycidyl group-containing (meth)acrylate copolymer, the epoxy resin, and the phenolic resin in the resin components of the adhesive composition.

[0184] [Hardening accelerator] Furthermore, a curing accelerator such as a tertiary amine, imidazole, or quaternary ammonium salt may be added to the thermosetting resin composition as needed. Such curing accelerators can be the same as those exemplified for the general-purpose die-bonding film adhesive composition. To prevent voids from forming at the bonding surface, the amount of the curing accelerator added is preferably within a range of 0.01 to 0.07 parts by mass based on 100 parts by mass of the epoxy resin and the phenolic resin combined.

[0185] [Inorganic fillers] Furthermore, the thermosetting resin composition may contain an inorganic filler as needed to improve the handling of the die-bonding film (adhesive layer) 3, adjust the fluidity during die bonding, impart thixotropy, and enhance bond strength. The inorganic filler can be the same as those exemplified for the general-purpose die-bonding film adhesive composition. Among these, silica fillers are particularly suitable for versatility. The content of the inorganic filler in the die-bonding film (adhesive layer) 3 is preferably within a range of 10% to 80% by mass, and more preferably within a range of 15% to 50% by mass, based on 100 parts by mass of the combined amount of the glycidyl-containing (meth)acrylate copolymer, epoxy resin, and phenolic resin in the resin component. Thus, the content is preferably 10% to 15% by mass, and more preferably 15% to 50% by mass. Moreover, the content ratio is preferably 80% by mass or less, more preferably 50% by mass or less. []

[0186] The inorganic filler is preferably a mixture of two or more inorganic fillers with different average particle sizes, in order to improve the severability of the die-bonding film (adhesive layer) 3 during cold expansion and to maximize adhesion after curing. Specifically, an inorganic filler with an average particle size of 0.1 μm to 5 μm is preferably used as the main inorganic filler component, accounting for at least 80% by mass of the total inorganic filler mass. If necessary to suppress foaming of the die-bonding film 3 during semiconductor wafer manufacturing due to excessive fluidity of the die-bonding film (adhesive layer) 3 or to improve adhesion after curing, an inorganic filler with an average particle size of less than 0.1 μm may be used in combination with the main inorganic filler component at a blending amount of 20% by mass, based on the total inorganic filler mass.

[0187] [Silane coupling agent] Furthermore, a silane coupling agent may be added to the thermosetting resin composition as needed to improve adhesion to the adherend. The silane coupling agent may be the same as those exemplified for use in the general-purpose die-bonding film adhesive composition. To prevent voids from forming at the bonding surface, the amount of the silane coupling agent added is preferably within a range of 0.5 parts by mass to 2.0 parts by mass based on 100 parts by mass of the epoxy resin and the phenolic resin combined.

[0188] [other] Furthermore, the thermosetting resin composition may contain a flame retardant or an ion scavenger, etc., within a range that does not impair the function of the die-bonding film 3. These flame retardants or ion scavengers may be the same as those exemplified for the general-purpose die-bonding film adhesive composition.

[0189] (Thickness of die-bonding film (adhesive layer)) The thickness of the bonding film (adhesive layer) 3 is not particularly limited. To ensure bonding strength, properly embed the wires connecting the semiconductor chip, and adequately fill uneven surfaces of the substrate's wiring circuits, it is preferably between 5 μm and 200 μm. If the bonding film (adhesive layer) 3 is less than 5 μm thick, there is a risk of insufficient bonding between the semiconductor chip and the lead frame or wiring board. On the other hand, if the bonding film (adhesive layer) 3 is thicker than 200 μm, it is uneconomical and may not adequately support the miniaturization and thinning of semiconductor devices. Furthermore, to ensure high bonding strength and enable thinner semiconductor devices, the film adhesive thickness is more preferably between 10 μm and 100 μm, and particularly preferably between 20 μm and 75 μm. Thus, the thickness of the die-bonding film (adhesive layer) 3 is preferably 5 μm or more, more preferably 10 μm or more, and particularly preferably 20 μm or more. Furthermore, the thickness is preferably 200 μm or less, more preferably 100 μm or less, and particularly preferably 75 μm or less. []

[0190] More specifically, when used as a general-purpose bonding film (adhesive layer), the thickness is, for example, 5 μm or more and less than 30 μm, particularly preferably 10 μm or more and 25 μm or less. When used as a wire-embedded bonding film (adhesive layer), the thickness is, for example, 30 μm or more and 100 μm or less, particularly preferably 40 μm or more and 80 μm or less. Thus, when used as a general-purpose bonding film (adhesive layer), the thickness is preferably 5 μm or more, more preferably 10 μm or more. Furthermore, the thickness is preferably less than 30 μm, more preferably 25 μm or less. Furthermore, when used as a wire-embedded bonding film (adhesive layer), the thickness is preferably 30 μm or more, more preferably 40 μm or more. Furthermore, the thickness is preferably 100 μm or less, more preferably 80 μm or less. []

[0191] (Method for manufacturing a die-bonding film) The above-mentioned bonding film (adhesive layer) 3 is manufactured, for example, as follows. First, a release liner is prepared. The release liner can be the same as the release liner disposed on the adhesive layer 2 of the dicing tape 10. Next, a coating solution for the bonding film (adhesive layer) 3, which is the material for forming the bonding film (adhesive layer) 3, is prepared. The coating solution can be prepared, for example, by uniformly mixing and dispersing a thermosetting resin composition containing the components of the bonding film (adhesive layer) 3, such as a glycidyl group-containing (meth)acrylate copolymer, an epoxy resin, a hardener for the epoxy resin, an inorganic filler, a hardening accelerator, and a silane coupling agent, with a diluent solvent. The solvent can be, for example, a general-purpose organic solvent such as methyl ethyl ketone or cyclohexanone.

[0192] Next, the coating solution for the bonding film (adhesive layer) 3 is applied to the release-treated surface of the release liner, which serves as a temporary support, and dried to form a bonding film (adhesive layer) 3 of a specific thickness. Thereafter, the release-treated surface of another release liner is bonded to the bonding film (adhesive layer) 3. The coating method is not particularly limited; for example, a die coater, a notch wheel coater (registered trademark), a gravure coater, a roll coater, a reverse roll coater, etc. can be used for coating. Furthermore, the drying conditions are preferably within a range of, for example, a drying temperature of 60°C to 200°C and a drying time of 1 minute to 90 minutes. Furthermore, in the present invention, a laminate having release liners on both sides or one side of the bonding film (adhesive layer) 3 is sometimes referred to as a bonding film (adhesive layer) 3.

[0193] (Manufacturing method of cutting die-bonding film) The manufacturing method of the dicing bonding film 20 is not particularly limited and can be manufactured by conventionally known methods. For example, the dicing bonding film 20 is first prepared separately from the dicing tape 10 and the bonding film 3. Then, the adhesive layer 2 of the dicing tape 10 and the release liner of the bonding film (adhesive layer) 3 are peeled off separately. The adhesive layer 2 of the dicing tape 10 and the bonding film (adhesive layer) 3 are then laminated together by, for example, pressing with a pressing roller such as a hot roll laminator. The laminating temperature is not particularly limited, but is preferably within a range of 10°C to 100°C. The laminating pressure (linear pressure) is preferably within a range of 0.1 kgf / cm to 100 kgf / cm. Furthermore, in the present invention, the laminate having the release liner on the adhesive layer 2 and the bonding film (adhesive layer) 3 is sometimes referred to as the dicing bonding film 20. In the dicing die-bonding film 20 , the release liner provided on the adhesive layer 2 and the die-bonding film (adhesive layer) 3 can be peeled off when the dicing die-bonding film 20 is operated.

[0194] The dicing film 20 may be in the form of a roll or a laminated sheet. Alternatively, the dicing tape 10 may be pre-cut into a specific size to form a sheet or tape.

[0195] For example, as disclosed in Japanese Patent Application Laid-Open No. 2011-159929, a plurality of island-shaped adhesive layers (bonding film 3) and an adhesive film (dicing tape 10) pre-cut into the shape of a semiconductor wafer can be formed on a release substrate (release liner). In this case, the dicing tape 10 is formed into a circular shape with a larger diameter than the bonding film (adhesive layer) 3, and the bonding film (adhesive layer) 3 is formed into a circular shape with a larger diameter than the semiconductor wafer 30. When pre-cutting the dicing tape 10 in this roll form, the dicing tape 10 may be partially heated and / or cooled to ensure continuous and efficient removal of excess dicing tape 10 without breaking. The heating temperature is appropriately selected, preferably ranging from 30°C to 120°C. The heating time is also appropriately selected, preferably ranging from 0.1 seconds to 10 seconds. The dicing tape 10 of the present invention has a certain degree of heat resistance, so even if it is heated at a high temperature of 120° C., it will not cause any special problems during operation.

[0196] <Method for manufacturing semiconductor wafer> FIG6 is a flow chart illustrating a method for manufacturing semiconductor wafers with a die-bonding film using a dicing die-bonding film 20 in which a die-bonding film (adhesive layer) 3 is laminated on the adhesive layer 2 of the dicing tape 10 of this embodiment. FIG7 is a schematic diagram showing a state in which a ring-shaped frame (wafer ring) 40 is attached to the outer edge of the dicing tape 10 (where the adhesive layer 2 is exposed) and singulated semiconductor wafers (plural semiconductor wafers) are attached to the die-bonding film (adhesive layer) 3 at the center. Furthermore, FIG8(a)-(f) are cross-sectional views illustrating an example of a grinding step for a semiconductor wafer having multiple modified regions formed by laser irradiation and a step for attaching multiple separated semiconductor wafers (plural semiconductor wafers) to the dicing die-bonding film 20. Figures 9(a) to (f) are cross-sectional views showing an example of a manufacturing method for obtaining individual semiconductor chips with bonding films from a plurality of cut thin-film semiconductor wafers bonded / held on a cutting bonding film 20, which includes a series of steps from expansion to picking up.

[0197] (Method for Manufacturing a Semiconductor Wafer Using a Die-Bonding Film 20) The method for manufacturing a semiconductor wafer using the dicing die-bonding film 20 is not particularly limited, and can be based on a conventionally known method. Here, a manufacturing method using SDBG (Stealth Dicing Before Griding) is used as an example for explanation.

[0198] First, as shown in FIG8(a), a semiconductor wafer W, for example, primarily composed of silicon, is prepared, with a plurality of integrated circuits (not shown) mounted on its first surface Wa (step S201 in FIG6 : preparation step). Next, a wafer processing tape (back grinding tape) T having an adhesive surface Ta is attached to the first surface Wa of the semiconductor wafer W.

[0199] Next, as shown in FIG8(b), while the semiconductor wafer W is held on wafer processing tape T, laser light with a focal point aligned within the wafer is irradiated from the side opposite the wafer processing tape T, i.e., the second surface Wb of the semiconductor wafer, along the grid-shaped planned cutting lines X. This creates ablation through multiphoton absorption to form modified regions 30b within the semiconductor wafer W (step S202 of FIG6: modified region formation step). The modified regions 30b are weakened regions that are used to separate the semiconductor wafer W into individual semiconductor chips during the grinding process. Regarding the method of forming the modified region 30b along the planned cutting line in the semiconductor wafer W by laser light irradiation, reference may be made to the methods disclosed in, for example, Japanese Patent No. 3408805, Japanese Patent Application Laid-Open No. 2002-192370, and Japanese Patent Application Laid-Open No. 2003-338567.

[0200] Next, as shown in FIG8(c), while the semiconductor wafer W is held on the wafer processing tape T, the semiconductor wafer W is thinned by grinding from the second surface Wb to a predetermined thickness. The thickness of the thinned semiconductor wafer 30 is preferably adjusted to 100 μm or less, more preferably 10 μm or more and 50 μm or less, from the perspective of reducing the thickness of the semiconductor device. Thus, the thickness of the thinned semiconductor wafer 30 is preferably 10 μm or more, more preferably 100 μm or less, and more preferably 50 μm or less. In this grinding / thinning step, when the grinding load of the grinding wheel is applied to the thinned semiconductor wafer 30, cracks grow vertically starting from the modified area 30b formed in Figure 8(b). The cracks are cut along the cutting line 30c corresponding to the cutting predetermined line X on the wafer processing tape T and singulated into a plurality of semiconductor chips 30a.

[0201] Next, as shown in Figures 8(d) and 8(e), the plurality of semiconductor wafers 30a held on the wafer processing tape T are bonded to the bonding film 3 of the separately prepared dicing bonding film 20 (step S204 of Figure 6: bonding step). In this step, after the release liner is peeled off from the adhesive layer 2 and bonding film (adhesive layer) 3 of the circularly cut dicing bonding film 20, a ring-shaped frame (wafer ring) 40 is attached to the outer edge of the dicing tape 10 (the exposed portion of the adhesive layer 2) of the dicing bonding film 20, as shown in Figure 7. Furthermore, the plurality of semiconductor wafers 30a held on the wafer processing tape T are bonded to the bonding film (adhesive layer) 3 laminated on the adhesive layer 2 of the dicing tape 10 in the center. Then, as shown in Figure 8(f), the wafer processing tape T is peeled off from the plurality of semiconductor wafers 30a on the film. The bonding is performed by pressing with a pressing means such as a pressure roller. The bonding temperature is not particularly limited, but is preferably in the range of 20°C to 130°C. From the perspective of reducing warping of the semiconductor wafer 30a, it is more preferably in the range of 40°C to 100°C. Thus, the bonding temperature is preferably 20°C or higher, more preferably 40°C or higher. Furthermore, the bonding temperature is preferably 130°C or lower, more preferably 100°C or lower. The bonding pressure is not particularly limited, but is preferably in the range of 0.1 MPa to 10.0 MPa. Since the dicing tape 10 of the present invention has a certain degree of heat resistance, there are no particular problems in its handling even when the bonding temperature is high.

[0202] Next, after attaching a ring frame 40 to the adhesive layer 2 of the dicing tape 10 in the die-bonding film 20, the dicing die-bonding film 20, along with the plurality of semiconductor wafers 30a, is secured to a holder 41 of the expansion device, as shown in FIG9(a). As shown in FIG9(b), the semiconductor wafer 30 (the plurality of semiconductor wafers 30a) whose film is cut along the cutting line 30c is attached to the bottom side of the semiconductor wafer 30 (the plurality of semiconductor wafers 30a), so that it can be singulated into the plurality of semiconductor wafers 30a with the die-bonding film. The die-bonding film 3, which will be cut along the predetermined cutting line X in the next step, is attached to the bottom side of the semiconductor wafer 30.

[0203] Next, as shown in FIG9(c), the first expansion step, or cold expansion step, is performed at a relatively low temperature (e.g., above -30°C and below 0°C). The bonding film (adhesive layer) 3 of the dicing bonding film 20 is cut into small pieces of bonding film (adhesive layer) 3a corresponding to the size of the semiconductor wafers 30a, resulting in semiconductor wafers 30a with bonding films 3a attached thereto (step S205 of FIG6: cold expansion step). In this step, a hollow cylindrical push-up member (not shown) included in the expansion device abuts against the dicing tape 10 from the underside of the dicing bonding film 20 and rises. The dicing tape 10, with the dicing bonding film 20 attached to the singulated semiconductor wafers 30 (plural semiconductor wafers 30a), is expanded by stretching it in two dimensions, including the diameter and circumference of the semiconductor wafers 30. The internal stress generated by cold expansion, which stretches the dicing tape 10 in all directions, is transmitted as external stress to the die-bonding film 3 attached to the singulated semiconductor wafer 30 (plural semiconductor chips 30a). Due to this external stress, the die-bonding film 3, which has become brittle at low temperatures, is cut into small pieces of die-bonding film 3a of the same size as the semiconductor chips 30a, resulting in semiconductor chips 30a with die-bonding film 3a attached.

[0204] The temperature conditions in the cold expansion step are, for example, -30°C to 0°C, preferably -20°C to -5°C, more preferably -15°C to -5°C, and particularly preferably -15°C. Thus, the temperature conditions are preferably -30°C to -20°C, more preferably 0°C to -5°C, and particularly preferably -15°C. [] The expansion speed (the speed at which the hollow cylindrical push-up member rises) during the cold expansion step is preferably in the range of 0.1 mm / s to 1000 mm / s, more preferably 10 mm / s to 300 mm / s. Thus, the expansion speed is preferably 0.1 mm / s to 10 mm / s, more preferably 10 mm / s to 300 mm / s. Furthermore, the expansion speed is preferably 1000 mm / s to 300 mm / s to 300 mm / s. Furthermore, the expansion amount (the height to which the hollow cylindrical push-up member rises) during the cold expansion step is preferably 3 mm to 16 mm.

[0205] Here, the dicing tape 10 of the present invention first adjusts the average value (Y MD + Y TD) / 2 of the elastic modulus of its base film 1 at 5% elongation at 0°C to an appropriate range of not less than 165 MPa and not more than 260 MPa. Therefore, the internal stress generated by the cold expansion of the dicing tape 10 in all directions is efficiently transmitted as external stress to the bonding film 3 tightly adhered to the adhesive layer 2 formed by containing a specific active energy line-curing adhesive composition. As a result, the bonding film 3 is cut neatly and with good yield. Furthermore, the dicing tape 10 of the present invention is composed of an adhesive composition whose main components are an acrylic adhesive polymer having a specific hydroxyl value in its adhesive layer 2 and a specific amount of a polyisocyanate crosslinking agent, and the equivalent ratio (-NCO) / (-OH) of the isocyanate group (-NCO) of the polyisocyanate crosslinking agent to the hydroxyl value (-OH) of the acrylic adhesive polymer is controlled to be greater than 0.14 and less than 1.32. Therefore, the adhesive layer 2 after the crosslinking reaction is given a hardness that can transmit a moderate impact to the edge of the solid crystal film 3 and the interface of the adhesive layer 2 directly below it at the moment the solid crystal film 3 is cut, and a cohesive force that can transmit stress in a direction away from the solid crystal film 3, and also gives a moderate initial adhesion to the solid crystal film 3. As a result, the bonding film 3a (adhesive layer) holding the small piece of semiconductor wafer 30a severed by cold expansion is moderately peeled from the adhesive layer 2 of the dicing tape 10 at its edge portion (the four peripheral portions), achieving a state of moderate partial peeling from the adhesive layer 2 of the dicing tape 10. Furthermore, at this time, the stress applied to the bonding film 3a and the adhesive layer 2, as well as the initial adhesion of the bonding film 3a, are moderately suppressed. Therefore, the severed bonding film is prevented from excessively peeling from the adhesive layer 2, ensuring a sufficient kerf width. Damage caused by collisions between semiconductor wafers and displacement from the fixed position on the adhesive layer 2 are also avoided.

[0206] Furthermore, in Figure 9(c), for convenience, the edge portion of the solid crystal film 3a (adhesive layer) that holds the small piece of semiconductor chip 30a is shown as being closely attached to the adhesive layer 2 of the dicing tape 10, but in fact, as shown in the enlarged cross-sectional view of Figure 10, the edge portion of the solid crystal film 3a (adhesive layer) that holds the small piece of semiconductor chip 30a is moderately peeled off from the adhesive layer 2 of the dicing tape 10, and the central portion of the solid crystal film 3a (adhesive layer) is closely attached to the adhesive layer 2 of the dicing tape 10.

[0207] After the cold expansion step, the hollow cylindrical push-up member of the expansion device is lowered to release the expanded state of the cutting tape 10.

[0208] Next, as shown in FIG9(d), a second expansion step, or room-temperature expansion step, is performed under relatively high temperature conditions (e.g., between 10°C and 30°C), thereby expanding the distance (kerf width) between the semiconductor wafers 30a with the die-bonding film (adhesive layer) 3a. In this step, a cylindrical table (not shown) included in the expansion device is positioned below the die-bonding film 20, abuts against the dicing tape 10, and rises to expand the dicing tape 10 while the die-bonding film 20 is being cut (step S206 in FIG6: room-temperature expansion step). The room-temperature expansion step ensures a sufficient distance (kerf width) between the semiconductor wafers 30a with the die-bonding film (adhesive layer) 3a, thereby improving the visibility of the semiconductor wafers 30a by a CCD camera, etc., and preventing the semiconductor wafers 30a with the die-bonding film (adhesive layer) 3a from reattaching due to contact between adjacent semiconductor wafers 30a during pickup. As a result, in the pickup step described later, the pickup performance of the semiconductor wafer 30a with the die-bonding film (adhesive layer) 3a is improved.

[0209] Furthermore, for convenience, FIG9(d) shows the edge of the die-bonding film 3a (adhesive layer) holding the small piece of semiconductor wafer 30a as being in close contact with the adhesive layer 2 of the dicing tape 10. However, as shown in the enlarged cross-sectional view of FIG10, the edge of the die-bonding film 3a (adhesive layer) holding the small piece of semiconductor wafer 30a is moderately peeled from the adhesive layer 2 of the dicing tape 10, while the center of the die-bonding film 3a (adhesive layer) is in close contact with the adhesive layer 2 of the dicing tape 10. During room-temperature expansion, the ambient temperature is higher than during cold expansion, resulting in a correspondingly higher adhesion between the die-bonding film 3a (adhesive layer) and the adhesive layer 2. Furthermore, expansion can be performed while suppressing the tensile stress incurred by the dicing tape 10. Therefore, during the room-temperature expansion step, some peeling of the die-bonding film 3a from the peeled state after cold expansion in FIG9(c) may occur, but excessive peeling is prevented.

[0210] The temperature condition in the room temperature expansion step is, for example, 10° C. or higher, preferably 15° C. or higher and 30° C. or lower. Thus, the temperature condition is preferably 10° C. or higher, more preferably 15° C. or higher, and further preferably 30° C. or lower. [] The expansion speed (the speed at which the cylindrical table rises) during the room temperature expansion step is, for example, in the range of 0.1 mm / s to 50 mm / s, preferably in the range of 0.3 mm / s to 30 mm / s. Thus, the expansion speed is preferably 0.1 mm / s to 0.3 mm / s to 30 mm / s. Furthermore, the expansion speed is preferably 50 mm / s to 30 mm / s to 30 mm / s. Furthermore, the expansion distance during the room temperature expansion step is, for example, in the range of 3 mm to 20 mm.

[0211] After the dicing tape 10 is expanded at room temperature by the rise of the table, the table vacuum-holds the dicing tape 10. Then, while maintaining this suction, the table descends during operation, releasing the expanded state of the dicing tape 10. After releasing the expanded state, to prevent the kerf width of the semiconductor wafer 30a with the die-bonding film (adhesive layer) 3a attached to the dicing tape 10 from narrowing, the circumference of the dicing tape 10, preferably outside the semiconductor wafer 30a holding area, is heated and contracted (heat-shrinked) by blowing hot air while the dicing tape 10 is vacuum-held to the table. This heat-shrinkage eliminates any slack in the dicing tape 10 caused by the expansion, maintaining a tense state. After this heat-shrinkage, the vacuum holding state of the table is released. The temperature of the hot air can be adjusted based on the physical properties of the base film 1, the distance between the hot air outlet and the dicing tape 10, and the air volume. For example, it is preferably within a range of 200°C to 250°C. The distance between the hot air outlet and the dicing tape 10 is preferably, for example, 15 mm to 25 mm. The air volume is preferably, for example, 35 L / min to 45 L / min. Furthermore, during the heat shrinking step, the stage of the expansion device is rotated at a speed of, for example, 3° / sec to 10° / sec, while hot air is blown along the circumference of the dicing tape 10 outside the semiconductor wafer 30a holding area.

[0212] The dicing tape 10 of the present invention preferably uses a resin film composed of a resin composition comprising a thermoplastic cross-linked resin (IO) composed of an ionic polymer of an ethylene / unsaturated carboxylic acid copolymer and a polyamide resin (PA) as its base film 1. Because the thermoplastic cross-linked resin (IO) is composed of an ionic polymer cross-linked by metal ions, it exhibits a sufficiently high recovery force upon heating to resist deformation after expansion, i.e., exhibits high heat shrinkage. Therefore, during the heat shrinking step, when high-temperature hot air is blown onto the slack portion (circumferential portion) of the dicing tape 10 caused by expansion, the circumferential portion of the dicing tape 10 can be heat-contracted without any problems, eliminating the slack. Therefore, the slit width expanded by normal temperature expansion can be maintained by maintaining the tension in the dicing tape 10.

[0213] FIG11 is an enlarged plan view of the state where the edge portion of the small piece of die-bonding film 3a is partially peeled off from the adhesive layer 2 of the dicing tape 10, observed from the back side (base film side) of the semiconductor chip 30a through a microscope after the above-mentioned cold expansion step to the shrinkage step. The area of ​​the edge portion of the small piece of bonding film 3a peeled from the adhesive layer 2 is not particularly limited within a range that does not impair the effects of the present invention. For example, in FIG11 , when a small piece of bonding film 3a is held on the adhesive layer 2 as viewed from the back side (base film side) of the semiconductor wafer 30a (corresponding to portion 9 of FIG10 ), the area of ​​the edge portion (hatched portion) of the small piece of bonding film 3a peeled from the adhesive layer 2 is denoted as S1, and the area of ​​the portion (white portion) of the small piece of bonding film 3a in close contact with the adhesive layer 2 is denoted as S2. The ratio of the area S1 of the edge portion of the small piece of bonding film 3a peeled from the adhesive layer 2 to the total area of ​​the small piece of bonding film 3a (= S1 + S2) is preferably in the range of 10% to 45%, and more preferably in the range of 15% to 40%. Thus, the ratio of the area S1 is preferably 10% or more, more preferably 15% or more, and preferably 45% or less, more preferably 40% or less. []

[0214] If the ratio of area S1 is less than 10%, the total force required to peel the semiconductor wafer 30a with the die-bonding film 3a from the adhesive layer 2 may not fully reflect the effect of reducing the adhesion force A after ultraviolet irradiation in the presence of oxygen, that is, the effect of reducing the force required to peel the edge portion of the semiconductor wafer 30a with the die-bonding film 3a. As a result, when pushing up from the bottom side of the dicing tape 10 using a push-up jig during pickup, as described later, it is difficult to create an opportunity for peeling from the edge portion. Therefore, there is a possibility that the effect of improving the pickup efficiency of the semiconductor wafer 30a with the die-bonding film 3a compared to the conventional method will be almost unobservable, or the effect may be only marginal.

[0215] If the ratio of the above-mentioned area S1 exceeds 45%, that is, if the bonding film 3 is excessively peeled from the adhesive layer 2 during the cold expansion step, sufficient external stress cannot be applied to the bonding film 3 through the adhesive layer 2, resulting in a possibility that the bonding film 3 cannot be neatly cut, or the incision width cannot be sufficiently ensured, or the incision width may vary. Furthermore, in subsequent manufacturing steps, the semiconductor wafer 30a with the bonding film 3a attached may be unintentionally shifted or detached. Furthermore, in the pickup step described later, when the excessively peeled bonding film is reattached to the adhesive layer 2, the reattachment area becomes excessively large. Therefore, even if the adhesive layer 2 is composed of an active energy ray-curable adhesive composition that meets the requirements of the present invention, in order to peel it from the bottom side of the dicing tape 10 by pushing it up with a jig, a large amount of energy may be required due to the large reattachment area. As a result, the pickup yield of the semiconductor wafer 30a with the die-bonding film 3a is reduced.

[0216] In other words, the aforementioned area S1 represents the area where the edge of the expanded and peeled die-bonding film 3a and the adhesive layer 2, exposed to air and exposed to ultraviolet light in the presence of oxygen, are momentarily reattached by the suction claws contacting / landing before being lifted from the underside of the dicing tape 10 by the lifting jig in the next pickup step. Therefore, when the ratio of the aforementioned area S1 is within a range of 10% to 40%, the adhesive layer 2, whose adhesion force A after ultraviolet light irradiation in the presence of oxygen is adjusted to 3.50 N / 25 mm, most effectively exhibits the function of reducing the force required to peel the edge of the semiconductor wafer 30a with the die-bonding film 3a attached thereto. On the other hand, in the area S2 of the die-bonding film 3a that is in close contact with the adhesive layer 2, which accounts for 55% to 90% of the total area of ​​the die-bonding film 3a, the adhesive strength B of the adhesive layer 2 after ultraviolet irradiation in an oxygen-free environment is adjusted to 0.25 N / 25 mm to 0.70 N / 25 mm. Therefore, subsequent to peeling of the edge of the die-bonding film 3a, peeling of the die-bonding film 3a from the adhesive layer 2 toward the center is facilitated. In the subsequent pickup step, the total energy required to peel the semiconductor wafer 30a with the die-bonding film 3a from the adhesive layer 2 is the sum of the peeling force reduction effects of the area S1 and the area S2. The dicing tape 10 of this embodiment, by balancing the ratio of the area S1 to the area S2, can easily reduce this total energy compared to conventional methods.

[0217] The method for determining the ratio of the areas S1 and S2 is not particularly limited and can be determined using conventionally known methods. For example, an image of the edge of the cut die-bonding film 3a partially peeled from the adhesive layer 2 of the dicing tape 10 is observed from the back side (base film side) of the semiconductor wafer using a microscope, and the portion corresponding to the area S1 and the portion corresponding to the area S2 are binarized using image processing software to determine the ratio of their respective areas. Alternatively, an image is printed on paper, and the respective portions are cut out along the shape of the image to measure the mass, and the ratio of the respective areas is determined from the mass ratio.

[0218] Next, the dicing tape 10 is irradiated with active energy rays from the substrate film 1 side, causing the adhesive layer 2 to harden and shrink, thereby reducing the adhesive layer 2's adhesion to the die-bonding film 3a (step S207 in FIG6 : active energy ray irradiation step). Examples of active energy rays used in the post-irradiation include ultraviolet rays, visible light, infrared rays, electron beams, beta rays, and gamma rays. Among these active energy rays, ultraviolet rays (UV) and electron beams (EB) are particularly preferred, with ultraviolet rays (UV) being particularly preferred. The light source used for the ultraviolet (UV) irradiation is not particularly limited; for example, black light, ultraviolet fluorescent lamps, low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultrahigh-pressure mercury lamps, carbon arc lamps, metal halide lamps, and xenon lamps can be used. Alternatively, ArF excimer lasers, KrF excimer lasers, excimer lamps, or synchrotron radiation can be used. The irradiation dose of the ultraviolet (UV) light is not particularly limited, but is preferably within a range of 100 mJ / cm² to 2,000 J / cm², more preferably 150 mJ / cm² to 1,000 J / cm². Thus, the irradiation dose is preferably 100 mJ / cm² or more, more preferably 150 mJ / cm² or more. Furthermore, the irradiation dose is preferably 2,000 J / cm² or less, more preferably 1,000 J / cm² or less. []

[0219] Here, the dicing tape 10 of the present invention, as described above, is a tape wherein the adhesive layer 2 comprising an active energy ray-curable adhesive composition containing an acrylic adhesive polymer having an active energy ray-reactive carbon-carbon double bond is subjected to an oxygen- and an oxygen-free atmosphere at a cumulative radiation intensity of 150 mJ / cm By adjusting the curing state of the adhesive layer 2 due to the crosslinking reaction, the adhesive layer 2 achieves a hardening state when irradiated with ultraviolet light in the presence of oxygen (peel angle: 90°, peel speed: 300 mm / min) on a stainless steel plate (SUS304·BA plate) at 23°C. The adhesive strength A (peel angle: 90°, peel speed: 300 mm / min) is kept within the range of 3.50 N / 25 mm or less, and a hardening state (peel angle: 90°, peel speed: 300 mm / min) on a stainless steel plate (SUS304·BA plate) at 23°C. The adhesive layer 2 is free of oxygen (peel angle: 90°, peel speed: 300 mm / min) is kept within the range of 0.25 N / 25 mm or more and 0.70 N / 25 mm or less. This reduces the force required to peel the semiconductor wafer 30a with the die-bonding film 3a from the adhesive layer 2 compared to conventional methods. As a result, the pickup of the semiconductor wafer 30a with the die-bonding film 3a is improved in the pickup step described later. In this case, the concentration of active energy ray-reactive carbon-carbon double bonds is preferably adjusted to a value within a range of 0.85 meq to 1.50 meq per 1 g of the active energy ray-curable adhesive composition.

[0220] Next, the semiconductor chips 30a with the die-bonding films (adhesive layers) 3a that have been singulated are peeled off from the adhesive layer 2 of the dicing tape 10 after being irradiated with ultraviolet light (UV) by so-called picking up (step S208 in FIG. 6 : peeling (picking up) step).

[0221] The above-mentioned pickup method includes, for example, a method in which, as shown in FIG9(e), a semiconductor wafer 30a with a bonding film (adhesive layer) 3a is contacted / landed on the surface of the semiconductor wafer 30a by a suction collet 50, and the second surface of the base film 1 of the dicing tape 10 is pushed up by an upward push pin 60 to promote peeling from the edge of the semiconductor wafer 30a with the bonding film 3a. Furthermore, as shown in FIG9(f), the semiconductor wafer 30a with the bonding film (adhesive layer) 3a pushed up is sucked and lifted up by the suction collet 50 of a pickup device (not shown) to be peeled from the adhesive layer 2 of the dicing tape 10. In this way, the semiconductor wafer 30a with the bonding film (adhesive layer) 3a can be obtained.

[0222] The pickup conditions are not particularly limited as long as they are within a practically acceptable range. Typically, the upward push speed of the push pin 60 is set within a range of 1 mm / s to 100 mm / s. However, when the thickness of the semiconductor wafer 30a (the thickness of the semiconductor wafer) is as thin as 100 μm, it is preferably set within a range of 1 mm / s to 20 mm / s to minimize damage to the thin film semiconductor wafer 30a. Furthermore, the speed can be set within a range of 5 mm / s to 20 mm / s to improve productivity. Thus, the upward push speed is preferably 1 mm / s to 100 mm / s, more preferably 5 mm / s to 20 mm / s. Furthermore, the upward push speed is preferably 100 mm / s to 20 mm / s to 20 mm / s. []

[0223] Furthermore, the push-up height of the push-up pin, which allows for pickup without damaging the semiconductor wafer 30a, can be preferably set within a range of 100 μm to 600 μm, for example, from the same perspective as above. From the perspective of reducing stress on the semiconductor thin film wafer, it can be more preferably set within a range of 100 μm to 450 μm. From the perspective of additional consideration of productivity, it can be particularly preferably set within a range of 100 μm to 350 μm. Dicing tapes that can achieve such a smaller push-up height can be said to have excellent pickup performance.

[0224] As described above, the dicing tape 10 of the present invention, which is composed of a base film 1 and an adhesive layer 2, is used in the semiconductor manufacturing process as a dicing die-cutting film 20 in which a die-cutting film (adhesive layer) 3 is laminated on the adhesive layer 2 of the dicing tape 10 in a peelable manner. Even when a die-cutting film with high fluidity and thick thickness such as a wire-embedded die-cutting film is applied, the die-cutting film 3 can be well cut by cold expansion, and the edge portion of the die-cutting film 3a after the cut is formed from the dicing film. The state in which the adhesive layer 2 of the tape 10 is appropriately peeled off greatly suppresses the phenomenon that the edge portion of the peeled solid film 3a of the individual semiconductor chip 30a with the solid film 3a attached thereto is strongly re-adhered to the adhesive layer 2 after ultraviolet irradiation to the extent that it cannot be easily peeled off even when the jig is pushed up from the bottom side of the dicing tape and sucked / pulled up with the suction claws. Therefore, the semiconductor chip 30a with the solid film 3a attached thereto can be well picked up from the adhesive layer 2 of the dicing tape 10 after ultraviolet irradiation.

[0225] Furthermore, the manufacturing method illustrated in Figures 9(a) to (f) is an example of a method for manufacturing a semiconductor wafer 30a using a dicing die-bonding film 20 (SDBG). The method of using dicing tape 10 as a form of dicing die-bonding film 20 is not limited to the above method. In other words, the dicing die-bonding film 20 can be used in any manner other than the above method, as long as it is attached to the semiconductor wafer 30 during dicing.

[0226] The dicing tape 10 of the present invention is particularly suitable for use as a dicing tape integrated with a wire-embedded die-bonding film to form a dicing die-bonding film 20 in methods for manufacturing thin-film semiconductor wafers, such as DBG, stealth dicing, and SDBG. Of course, it can also be integrated with a general-purpose die-bonding film.

[0227] <Method for Manufacturing Semiconductor Device> A semiconductor device equipped with a semiconductor wafer manufactured using a dicing die-bonding film 20 in which the dicing tape 10 to which this embodiment is applied and the die-bonding film 3 are integrated will be specifically described below.

[0228] A semiconductor device (semiconductor package) can be obtained by, for example, heating and pressing the semiconductor chip 30a with the above-mentioned die-bonding film (adhesive layer) 3a to a semiconductor chip mounting support member or a semiconductor chip, and then going through steps such as a wire bonding step and a sealing step with a sealing material.

[0229] FIG12 is a schematic cross-sectional view of one embodiment of a semiconductor device comprising a laminated structure in which a semiconductor wafer is mounted, manufactured using a dicing die-bonding film 20 that integrates the dicing tape 10 according to this embodiment with a wire-embedded die-bonding film 3. The semiconductor device 70 shown in FIG12 comprises a semiconductor wafer mounting support substrate 71, cured die-bonding films (adhesive layers) 3a1 and 3a2, a first-stage semiconductor wafer 30a1, a second-stage semiconductor wafer 30a2, and a sealing material 75. The semiconductor wafer mounting support substrate 71, the cured die-bonding film 3a1, and the semiconductor wafer 30a1 constitute a support member 76 for the semiconductor wafer 30a2.

[0230] A plurality of external connection terminals 72 are arranged on one surface of a semiconductor wafer mounting support substrate 71, and a plurality of terminals 73 are arranged on the other surface of the semiconductor wafer mounting support substrate 71. The semiconductor wafer mounting support substrate 71 has wires 74 for electrically connecting the connection terminals (not shown) of the semiconductor wafers 30a1 and 30a2 to the external connection terminals 72. The semiconductor wafer 30a1 is bonded to the semiconductor wafer mounting support substrate 71 by a cured bonding film 3a1, burying the unevenness resulting from the external connection terminals 72. The semiconductor wafer 30a2 is bonded to the semiconductor wafer 30a1 by a cured bonding film 3a2. The semiconductor wafers 30a1, 30a2, and wires 74 are sealed by a sealing material 75. In this manner, the wire-embedded bonding film 3a is suitable for use in semiconductor devices constructed by stacking a plurality of semiconductor wafers 30a.

[0231] FIG13 is a schematic cross-sectional view of another embodiment of a semiconductor device mounted with a semiconductor wafer manufactured using a dicing die-bonding film 20 that integrates the dicing tape 10 according to this embodiment with a general-purpose die-bonding film 3. The semiconductor device 80 shown in FIG13 includes a semiconductor wafer mounting support substrate 81, a cured die-bonding film 3a, a semiconductor wafer 30a, and a sealing material 85. The semiconductor wafer mounting support substrate 81 serves as a support member for the semiconductor wafer 30a and has wires 84 for electrically connecting the connection terminals (not shown) of the semiconductor wafer 30a to external connection terminals (not shown) disposed on the main surface of the semiconductor wafer mounting support substrate 81. The semiconductor wafer 30a is bonded to the semiconductor wafer mounting support substrate 81 via the cured die-bonding film 3a. The semiconductor wafer 30a and the wires 7 are sealed with a sealing material 85. [Example]

[0232] The present invention is further described in detail with reference to the following examples, but the present invention is not limited thereto.

[0233] 1. Preparation of substrate film 1 As materials for producing the base films 1(a) to 1(k), the following resins were prepared.

[0234] (Thermoplastic cross-linked resin (A) composed of an ionomer of an ethylene / unsaturated carboxylic acid copolymer) ･Resin (IO1) A terpolymer composed of ethylene / methacrylic acid / 2-methyl-propyl acrylate in a mass ratio of 80 / 10 / 10, with a Zn2+ ion neutralization degree of 60 mol%, a melting point of 86°C, an MFR of 1 g / 10 min (190°C / 2.16 kg load), and a density of 0.96 g / cm3. ･Resin (IO2) A terpolymer composed of ethylene / methacrylic acid / 2-methyl-propyl acrylate in a mass ratio of 80 / 10 / 10, with a Zn2+ ion neutralization degree of 70 mol%, a melting point of 87°C, an MFR of 1 g / 10 min (190°C / 2.16 kg load), and a density of 0.96 g / cm3.

[0235] (Polyamide resin (B)) ･Resin (PA1) Nylon 6, melting point: 225℃, density: 1.13g / cm3

[0236] (Other resins (C)) ･Resin (TPO) Thermoplastic polyolefin elastomer (ethylene-α-olefin random copolymer) ･Resin (POPE) Polyolefin-polyether block copolymer (polymer antistatic agent), melting point: 115°C, MFR: 15g / 10min (190°C / 2.16kg load) ･Resin (PP) Random copolymer polypropylene, melting point 138℃ ･Resin (EVA) Ethylene-vinyl acetate copolymer, vinyl acetate content 20% by mass, melting point 82°C, density: 0.94 g / cm3

[0237] (Substrate Film 1(a)) A thermoplastic crosslinked resin (A) composed of an ionomer (IO1) and a polyamide resin (B) (PA1) were prepared. First, the thermoplastic crosslinked resin (A) (IO1) composed of the ionomer and the polyamide resin (B) (PA1) were dry-blended at a mass ratio of (A):(B) = 95:5. The dry-blended mixture was then fed into the resin inlet of a twin-screw extruder and melt-kneaded at a die temperature of 230°C to obtain a resin composition for substrate film 1(a). The resulting resin composition was fed into separate extruders using a single (same resin) three-layer T-die film forming machine and formed at a processing temperature of 240°C to produce a substrate film 1(a) having a thickness of 90 μm and composed of three layers of the same resin composition. The thickness of each layer was set to 20 μm / 50 μm / 20 μm for the first layer (the surface adjacent to the adhesive layer 2) / the second layer / the third layer. The mass ratio of the total amount of the thermoplastic cross-linked resin (A) composed of an ionomer to the total amount of the polyamide resin (B) in the entire layer was (A) / (B) = 95:5.

[0238] (Substrate film 1(b)) The aforementioned thermoplastic crosslinked resin (A) (IO1) composed of an ionomer and the aforementioned polyamide resin (B) (PA1) were dry-blended at a mass ratio of (A):(B) = 90:10. A three-layer substrate film 1(b) with a thickness of 90 μm and composed of the same resin composition was prepared in the same manner as substrate film 1(a). The thickness of each layer was set to: 1st layer (side adjacent to adhesive layer 2) / 2nd layer / 3rd layer = 20 μm / 50 μm / 20 μm. The mass ratio of the total amount of the thermoplastic crosslinked resin (A) composed of an ionomer to the total amount of the polyamide resin (B) in the entire layer was: (A) total amount: (B) total amount = 90:10.

[0239] (Substrate Film 1(c)) The aforementioned thermoplastic crosslinked resin (A) (IO1) composed of an ionomer and the aforementioned polyamide resin (B) (PA1) were dry-blended at a mass ratio of (A):(B) = 85:15. A three-layer substrate film 1(c) with a thickness of 90 μm was prepared in the same manner as substrate film 1(a), except that the mixture was dry-blended. The thickness of each layer was set to: 1st layer (side adjacent to adhesive layer 2) / 2nd layer / 3rd layer = 20 μm / 50 μm / 20 μm. The mass ratio of the total amount of thermoplastic crosslinked resin (A) composed of an ionomer to the total amount of polyamide resin (B) in the entire layer was: (A) total amount: (B) total amount = 85:15.

[0240] (Substrate Film 1(d)) The aforementioned thermoplastic crosslinked resin (A) (IO1) composed of an ionomer and the aforementioned polyamide resin (B) (PA1) were dry-blended at a mass ratio of (A):(B) = 80:20. A three-layer substrate film 1(d) with a thickness of 90 μm and composed of the same resin composition was prepared in the same manner as substrate film 1(a). The thickness of each layer was set to: 1st layer (side adjacent to adhesive layer 2) / 2nd layer / 3rd layer = 20 μm / 50 μm / 20 μm. The mass ratio of the total amount of the thermoplastic crosslinked resin (A) composed of an ionomer to the total amount of the polyamide resin (B) in the entire layer was: (A) total amount: (B) total amount = 80:20.

[0241] (Base film 1(e)) The aforementioned thermoplastic crosslinked resin (A) (IO1) composed of an ionomer and the aforementioned polyamide resin (B) (PA1) were dry-blended at a mass ratio of (A):(B) = 72:28. A three-layer substrate film 1(e) with a thickness of 90 μm and composed of the same resin composition was prepared in the same manner as substrate film 1(a), except that the mixture was dry-blended. The thickness of each layer was set to: 1st layer (side adjacent to adhesive layer 2) / 2nd layer / 3rd layer = 20 μm / 50 μm / 20 μm. The mass ratio of the total amount of the thermoplastic crosslinked resin (A) composed of an ionomer to the total amount of the polyamide resin (B) in the entire layer was: (A) total amount: (B) total amount = 72:28.

[0242] (Base film 1(f)) As the thermoplastic crosslinked resin (A) composed of an ionomer, (IO1) was prepared; as the polyamide resin (B), (PA1) was prepared; and as the other resin (C), a thermoplastic polyolefin elastomer (ethylene-α-olefin random copolymer) (TPO) and a polyolefin-polyether block copolymer (POPE) were prepared. First, as the resins for the first and second layers, the thermoplastic crosslinked resin (A) composed of an ionomer (IO1) and the polyamide resin (B) (PA1) were dry-blended at a mass ratio of (A):(B) = 90:10. The dry-blended mixture was then fed into the resin inlet of a twin-screw extruder and melt-kneaded at a die temperature of 230°C to obtain the resin compositions for the first and second layers of the substrate film 1 (g). Furthermore, as the resin for the third layer, a thermoplastic crosslinked resin (A) (IO1) composed of an ionomer, a polyamide resin (B) (PA1), a thermoplastic polyolefin elastomer (TPO), and a polyolefin-polyether block copolymer (POPE) were dry-blended at a mass ratio of 76:8:8:8, respectively. The dry-blended mixture was then fed into the resin inlet of a twin-screw extruder and melt-kneaded at a die temperature of 230°C to obtain the resin composition for the third layer of substrate film 1(f). The respective resin compositions and resins were fed into separate extruders using a two-resin, three-layer T-die film forming machine and formed at a processing temperature of 240°C to produce a substrate film 1(f) with a thickness of 80 μm and composed of three layers composed of two resin compositions. The thickness of each layer was set to 30 μm / 30 μm / 20 μm for the first layer (the surface adjacent to the adhesive layer 2) / the second layer / the third layer. The mass ratio of the total amount of the thermoplastic crosslinked resin (A) composed of an ionomer to the total amount of the polyamide resin (B) in the entire layer was (A) / (B) = 90:10. Furthermore, the total content of the resin (A) and the resin (B) in the entire layer was 95% by mass.

[0243] (Base film 1(g)) As the thermoplastic crosslinked resin (A) composed of an ionomer, (IO1) was prepared; as the polyamide resin (B), (PA1) was prepared; and as the other resin (C), a thermoplastic polyolefin elastomer (ethylene-α-olefin random copolymer) (TPO) was prepared. First, as the resins for the first and third layers, the thermoplastic crosslinked resin (A) composed of an ionomer (IO1) and the polyamide resin (B) (PA1) were dry-blended at a mass ratio of (A):(B) = 85:15. The dry-blended mixture was then fed into the resin inlet of a twin-screw extruder and melt-kneaded at a die temperature of 230°C to obtain the resin compositions for the first and third layers of the substrate film 1 (g). Furthermore, as the resin for the second layer, the thermoplastic polyolefin elastomer (ethylene-α-olefin random copolymer) (TPO) was used alone. The respective resin compositions and resins were fed into separate extruders using two (two resin) three-layer T-die film forming machines and formed at a processing temperature of 240°C to produce a 90μm thick base film (1g) composed of three layers of the two resin compositions. The thickness of each layer was set to: 1st layer (side adjacent to adhesive layer 2) / 2nd layer / 3rd layer = 30μm / 30μm / 30μm. The mass ratio of the total amount of the thermoplastic crosslinked resin (A) composed of an ionomer to the total amount of the polyamide resin (B) in the entire layer was (A) total amount: (B) total amount = 85:15. Furthermore, the total content of the resin (A) and the resin (B) in the entire layer was 67% by mass.

[0244] (Base film 1(h)) As the thermoplastic crosslinked resin (A) composed of an ionomer, (IO1) and (IO2) were prepared, and as the polyamide resin (B), (PA1) was prepared. First, as the resins for the first and third layers, the thermoplastic crosslinked resin (A) composed of an ionomer (IO1) and the polyamide resin (B) composed of (PA1) were dry-blended at a mass ratio of (A):(B) = 90:10. The dry-blended mixture was then fed into the resin inlet of a twin-screw extruder and melt-kneaded at a die temperature of 230°C to obtain the resin compositions for the first and third layers of the substrate film 1 (h). Furthermore, as the resin for the second layer, (IO2) as the thermoplastic crosslinked resin (A) composed of an ionomer was used alone. The respective resin compositions and resins were fed into separate extruders using two different (two resin) three-layer T-die film forming machines and formed at a processing temperature of 240°C to produce a 90μm thick substrate film (1g) composed of three layers of the two resin compositions. The thickness of each layer was 30μm / 30μm / 30μm for the first layer (the side adjacent to the adhesive layer 2) / 2nd layer / 3rd layer. The mass ratio of the total amount of the thermoplastic crosslinked resin (A) composed of an ionomer to the total amount of the polyamide resin (B) in the layers was (A) / (B) = 93:7.

[0245] (Base film 1(i)) As the resin (A) composed of an ionomer, (IO1) was prepared. A base film 1(i) with a thickness of 90 μm and composed of three layers made of the same resin composition (containing only the resin (A) composed of an ionomer) was prepared in the same manner as base film 1(a), except that the polyamide resin (B) = (PA1) was not dry-blended. The thickness of each layer was set to 1st layer (the side adjacent to adhesive layer 2) / 2nd layer / 3rd layer = 20 μm / 50 μm / 20 μm.

[0246] (Base film 1(j)) A 90 μm thick three-layer substrate film 1 (j) was prepared in the same manner as substrate film 1 (g), except that the thickness of each layer of substrate film 1 was set to 1st layer (side adjacent to adhesive layer 2) / 2nd layer / 3rd layer = 20 μm / 50 μm / 20 μm. The total mass ratio of the total amount of thermoplastic crosslinked resin (A) composed of an ionomer to the total amount of polyamide resin (B) in the entire layer was (A) / (B) = 90:10. The total mass ratio of resin (A) and resin (B) in the entire layer was 44% by mass.

[0247] (Base film 1(k)) As other resins (C), (PP) and (EVA) were prepared. (PP) was used as the resin for the first and third layers, and (EVA) was used as the resin for the second layer. Two different resins (two different resins) were fed into separate extruders using a three-layer T-die film molding machine and molded at a processing temperature of 150°C. This produced a three-layer substrate film 1 (k) composed of two different resin compositions with a thickness of 80 μm. The thickness of each layer was set to: first layer (side adjacent to the adhesive layer) / second layer / third layer = 8 μm / 64 μm / 8 μm.

[0248] [Elastic modulus of base film at 5% elongation] The elastic modulus Y MD at 5% elongation in the MD direction and the elastic modulus Y TD at 5% elongation in the TD direction of the substrate film 1 at 0°C were measured using the following method. First, a test piece with a length of 100 mm (MD direction) and a width of 10 mm (TD direction) was prepared as a specimen for MD measurement (N = 5 specimens). A test piece with a length of 100 mm (TD direction) and a width of 10 mm (MD direction) was prepared as a specimen for TD measurement (N = 5 specimens). Next, using a tension-compression testing machine (Model: Minebea TechnoGraph TG-5kN) manufactured by Minebea Mitsumi Co., Ltd., the specimen was fixed at both ends of the longitudinal direction with chucks, with an initial distance between the chucks of 20 mm. The specimen was placed in a thermostatic bath (Model: THB-A13-038) manufactured by Minebea Mitsumi Co., Ltd. at 0°C for 1 minute. Afterwards, a tensile test was performed at a speed of 100 mm / min to measure the tensile load-elongation curve. From the resulting tensile load-elongation curve, the slope of the straight line connecting the origin (elongation start point) and the point on the curve corresponding to a 1.0 mm elongation from the origin (5% elongation relative to an initial distance of 20 mm between the chucks) was calculated. The modulus of elasticity (Y) at 5% elongation (unit: MPa) was calculated using the above formula. Measurements were performed on five specimens in each direction, and the average values ​​were used as the elastic modulus at 5% elongation in the MD direction (Y MD) and the elastic modulus at 5% elongation in the TD direction (Y TD). Using these values, the average elastic modulus at 5% elongation at 0°C of the substrate film 1 prepared above was calculated as (Y MD + Y TD) / 2.

[0249] The average values ​​of the elastic modulus (Y MD + Y TD) / 2 at 5% elongation at 0°C for the substrate films 1 (a) to 1 (k) used as the substrate film 1 of the dicing tape 10 of the embodiment and the comparative example are shown in Tables 1 to 9, respectively.

[0250] 2. Preparation of adhesive composition solution A solution of the following active energy ray-curable acrylic adhesive composition 2(a) to 2(u) was prepared as the adhesive composition for the adhesive layer 2 of the dicing tape 10. Furthermore, as a copolymerization monomer component constituting the base polymer (acrylate copolymer) of these adhesive compositions, a ･2-Ethylhexyl acrylate (2-EHA, molecular weight: 184.3, Tg: -70℃)、 ･2-Hydroxyethyl Acrylate (2-HEA, molecular weight: 116.12, Tg: -15℃), ･Methacrylic acid (MAA, molecular weight: 86.06, Tg: 228°C).

[0251] In addition, as a polyisocyanate crosslinking agent, a product manufactured by Tosoh Co., Ltd. TDI-based polyisocyanate crosslinker (trade name: Coronate L-45E, solid content: 45% by mass, isocyanate group content in solution: 8.05% by mass, isocyanate group content in solids: 17.89% by mass, calculated number of isocyanate groups: average 2.8 per molecule, theoretical molecular weight: 656.64) HDI-based polyisocyanate crosslinker (trade name: Coronate HL, solids concentration: 75% by mass, isocyanate group content in solution: 12.8% by mass, isocyanate group content in solids: 17.07% by mass, calculated number of isocyanate groups: average 2.6 per molecule, theoretical molecular weight: 638.75).

[0252] (Solution of active energy ray-curable acrylic adhesive composition 2(a)) As copolymerizable monomer components, 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), and methyl methacrylate (MMA) were prepared. These copolymerizable monomer components were mixed to a copolymerization ratio of 2-EHA / 2-HEA / MMA = 81.5 parts by mass / 17.5 parts by mass / 1.0 part by mass (= 442.21 mmol / 150.71 mmol / 11.62 mmol). A solution of a hydroxyl-containing base polymer (acrylate copolymer) was synthesized by solution free radical polymerization using ethyl acetate as the solvent and azobisisobutyronitrile (AIBN) as the initiator. The Tg of the resulting base polymer, calculated using the Fox equation, was -61°C.

[0253] Next, 19.2 parts by mass (123.75 mmol: 82.11 mol % relative to 2-HEA) of 2-isocyanatoethyl methacrylate (trade name: Karenz MOI, molecular weight: 155.15, isocyanate group: 1 / molecule, double bond group: 1 / molecule) manufactured by Showa Denko K.K., which is an active energy ray-reactive compound, was added to 100 parts by mass of the solid content of the base polymer. The mixture was reacted with a portion of the hydroxyl groups of 2-HEA to synthesize a solution of an acrylic adhesive polymer (A) having a carbon-carbon double bond in its side chain (solid content concentration: 50% by mass, weight average molecular weight Mw: 330,000, solid content hydroxyl value: 12.7 mgKOH / g, solid content acid value: 5.5 mgKOH / g, carbon-carbon double bond content: 1.04 meq / g). Furthermore, during the above reaction, 0.05 parts by mass of hydroquinone / monomethyl ether was used as a polymerization inhibitor to maintain the reactivity of carbon-carbon double bonds.

[0254] Next, 200 parts by mass of the solution of the acrylic adhesive polymer (A) synthesized above (100 parts by mass in terms of solid content) were mixed with 4.0 parts by mass of an α-hydroxyalkylphenone-based photopolymerization initiator (trade name: Omnirad 184) manufactured by IGM Resins BV, 0.8 parts by mass of a benzyl methyl ketal-based photopolymerization initiator (trade name: Omnirad 651) manufactured by IGM Resins BV, 1.0 parts by mass of an α-aminoalkylphenone-based photopolymerization initiator (trade name: Omnirad 379EG) manufactured by IGM Resins BV, 0.4 parts by mass of an acylphosphine oxide-based photopolymerization initiator (trade name: Omnirad 819) manufactured by IGM Resins BV, and an HDI-based polyisocyanate-based crosslinking agent (trade name: Coronate 100) manufactured by Tosoh Corporation as a crosslinking agent. HL, solid content concentration: 75% by mass, 5.5 parts by mass (4.1 parts by mass, 7.65 mmol in terms of solid content) was diluted with ethyl acetate and stirred to prepare a solution of active energy ray-curable acrylic adhesive composition 2(a) with a solid content concentration of 22% by mass. As shown in Table 1, in active energy ray-curable acrylic adhesive composition 2(a), the equivalent ratio (NCO / OH) of the isocyanate group (NCO) of the polyisocyanate crosslinker to the hydroxyl group (OH) of the acrylic adhesive polymer was 0.74, the residual hydroxyl group concentration was 0.06 mmol / g, and the carbon-carbon double bond concentration was 1.00 meq / g.

[0255] (Solution of active energy ray-curable acrylic adhesive compositions 2(b) to 2(u)) For the acrylic adhesive polymer (A), solutions of acrylic adhesive polymers (B) to (G) were synthesized by appropriately varying the copolymerization ratio of the copolymerizable monomer components, the amount of the active energy ray-reactive compound, and the copolymerizable monomer components, as shown in Tables 4, 5, and 9, respectively. The Tg, weight-average molecular weight (Mw), acid value, and hydroxyl value of the base polymers in the synthesized acrylic adhesive polymers (B) to (G) are shown in Tables 4, 5, and 9, respectively. Next, using these acrylic adhesive polymer solutions, a photopolymerization initiator and a polyisocyanate crosslinker were appropriately added, as shown in Tables 3 to 6, 8, and 9, respectively, per 100 parts by mass of the solid content of the acrylic adhesive polymers (A) to (G), to prepare solutions of active energy ray-curable acrylic adhesive compositions 2(b) to 2(u). In active energy ray-curable acrylic adhesive compositions 2(b) to 2(u), the equivalent ratio (NCO / OH) of isocyanate groups (NCO) in the polyisocyanate crosslinker to hydroxyl groups (OH) in the acrylic adhesive polymer, the residual hydroxyl group concentration, and the carbon-carbon double bond concentration are shown in Tables 3 to 6, 8, and 9, respectively.

[0256] 3. Preparation of adhesive composition solution The adhesive composition used for the die-bonding film (adhesive layer) 3 for cutting the die-bonding film 20 is prepared by preparing a solution of the following adhesive compositions 3(a) to 3(d).

[0257] (Solution of Adhesive Composition 3(a)) Prepare the following adhesive composition solution 3(a) for wire embedding type die bonding film. First, 26 parts by mass of a bisphenol-type epoxy resin (trade name: R2710, epoxy equivalent: 170, molecular weight: 340, liquid at room temperature) manufactured by Printec Co., Ltd. as a thermosetting resin, 36 parts by mass of a cresol novolac-type epoxy resin (trade name: YDCN-700-10, epoxy equivalent: 210, softening point: 80°C) manufactured by Tohto Kasei Co., Ltd., 1 part by mass of a phenolic resin (trade name: Milex XLC-LL, hydroxyl equivalent: 175, softening point: 77°C, water absorption: 1% by mass, mass loss on heating: 4% by mass) manufactured by Mitsui Chemicals, Inc. as a crosslinking agent, 25 parts by mass of a phenolic resin (trade name: HE200C-10, hydroxyl equivalent: 200, softening point: 71°C, water absorption: 1% by mass, mass loss on heating: 4% by mass) manufactured by Air Water Co., Ltd., and 10 parts by mass of a phenolic resin (trade name: Air Water Co., Ltd., To a resin composition consisting of 12 parts by mass of a phenolic resin manufactured by Water Co., Ltd. (trade name: HE910-10, hydroxyl equivalent: 101, softening point: 83°C, water absorption: 1 mass%, mass loss upon heating: 3 mass%), 15 parts by mass of a silica filler dispersion manufactured by Admatechs Co., Ltd. (trade name: SC2050-HLG, average particle size: 0.50 μm) as an inorganic filler, 14 parts by mass of a silica filler dispersion manufactured by Admatechs Co., Ltd. (trade name: SC1030-HJA, average particle size: 0.25 μm), and 1 part by mass of silica manufactured by Aerosil Co., Ltd. (trade name: Aerosil R972, average particle size: 0.016 μm), cyclohexanone as a solvent was added, the mixture was stirred and mixed, and then dispersed using a bead mill for 90 minutes.

[0258] Next, 37 parts by mass of a glycidyl group-containing (meth)acrylate copolymer having a low weight average molecular weight (Mw) as a thermoplastic resin, 9 parts by mass of a glycidyl group-containing (meth)acrylate copolymer having a high weight average molecular weight (Mw), 0.7 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUC A-1160) manufactured by GE Toshiba Corporation, 0.3 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUC A-189) manufactured by GE Toshiba Corporation as a silane coupling agent, and 0.03 parts by mass of 1-cyanoethyl-2-phenylimidazole (trade name: Curezol 2PZ-CN) manufactured by Shikoku Chemicals Co., Ltd. as a curing accelerator were added to the above resin composition and stirred and mixed. The mixture was filtered through a 100-mesh filter and vacuum degassed to prepare a solution of adhesive composition 3(a) having a solid content concentration of 20% by mass. The ratio of each resin component within the total resin content (the combined mass of the thermoplastic resin, thermosetting resin, and crosslinking agent) is: glycidyl-containing (meth)acrylate copolymer: epoxy resin: phenol resin = 31.5% by mass: 42.5% by mass: 26.0% by mass. The inorganic filler content is 20.5% by mass relative to the total resin content.

[0259] (Solution of Adhesive Composition 3(b)) The following adhesive composition solution 3 (b) was prepared as a wire embedding die bonding film. First, 21 parts by weight of bisphenol F epoxy resin (trade name: YDF-8170C, epoxy equivalent: 159, molecular weight: 310, liquid at room temperature) manufactured by Tohto Chemical Industry Co., Ltd. as a thermosetting resin, 33 parts by weight of cresol novolac epoxy resin (trade name: YDCN-700-10, epoxy equivalent: 210, softening point: 80°C) manufactured by Tohto Chemical Industry Co., Ltd., and AIR as a crosslinking agent were added. To a resin composition consisting of 46 parts by mass of a phenolic resin manufactured by Water Co., Ltd. (trade name: HE200C-10, hydroxyl equivalent: 200, softening point: 71°C, water absorption: 1% by mass, mass loss upon heating: 4% by mass) and 18 parts by mass of a silica filler dispersion manufactured by Admatechs Co., Ltd. (trade name: SC1030-HJA, average particle size: 0.25 μm) as an inorganic filler, cyclohexanone was added as a solvent, the mixture was stirred, and further dispersed using a bead mill for 90 minutes.

[0260] Next, 16 parts by mass of a glycidyl group-containing (meth)acrylate copolymer having a low weight average molecular weight (Mw) as a thermoplastic resin, 64 parts by mass of a glycidyl group-containing (meth)acrylate copolymer having a high weight average molecular weight (Mw), 1.3 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUC A-1160) manufactured by GE Toshiba Corporation, 0.6 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUC A-189) manufactured by GE Toshiba Corporation as a silane coupling agent, and 0.05 parts by mass of 1-cyanoethyl-2-phenylimidazole (trade name: Curezol 2PZ-CN) manufactured by Shikoku Chemicals Co., Ltd. as a curing accelerator were added to the above resin composition and stirred and mixed. The mixture was filtered through a 100-mesh filter and vacuum degassed to prepare a solution of adhesive composition 3(b) having a solid content concentration of 20% by mass. The proportions of each resin component within the total resin content (the combined mass of the thermoplastic resin, thermosetting resin, and crosslinking agent) are: glycidyl-containing (meth)acrylate copolymer: epoxy resin: phenol resin = 44.4% by mass: 30.0% by mass: 25.6% by mass. The inorganic filler content is 10.0% by mass relative to the total resin content.

[0261] (Solution of Adhesive Composition 3(c)) The following adhesive composition solution 3 (c) was prepared as a wire embedding die-bonding film. First, 11 parts by mass of a bisphenol epoxy resin (trade name: R2710, epoxy equivalent: 170, molecular weight: 340, liquid at room temperature) manufactured by Printec Co., Ltd. as a thermosetting resin, 40 parts by mass of a dicyclopentadiene epoxy resin (trade name: HP-7200H, epoxy equivalent: 280, softening point: 83°C) manufactured by DIC Co., Ltd., 18 parts by mass of a bisphenol S epoxy resin (trade name: EXA-1514, epoxy equivalent: 300, softening point: 75°C) manufactured by DIC Co., Ltd., 1 part by mass of a phenol resin (trade name: Milex XLC-LL, hydroxyl equivalent: 175, softening point: 77°C, water absorption: 1% by mass, mass loss upon heating: 4% by mass) manufactured by Mitsui Chemicals, Inc. as a crosslinking agent, and 1 part by mass of an AIR To a resin composition consisting of 20 parts by mass of a phenolic resin manufactured by WATER Co., Ltd. (trade name: HE200C-10, hydroxyl equivalent: 200, softening point: 71°C, water absorption: 1 mass%, mass loss upon heating: 4 mass%), 10 parts by mass of a phenolic resin manufactured by AIR WATER Co., Ltd. (trade name: HE910-10, hydroxyl equivalent: 101, softening point: 83°C, water absorption: 1 mass%, mass loss upon heating: 3 mass%), 24 parts by mass of a silica filler dispersion manufactured by Admatechs Co., Ltd. (trade name: SC1030-HJA, average particle size: 0.25 μm) as an inorganic filler, and 0.8 parts by mass of silica manufactured by Nippon Aerosil Co., Ltd. (trade name: Aerosil R972, average particle size: 0.016 μm), cyclohexanone as a solvent was added, the mixture was stirred and mixed, and then dispersed using a bead mill for 90 minutes.

[0262] Next, 30 parts by mass of a glycidyl group-containing (meth)acrylate copolymer having a low weight average molecular weight (Mw) as a thermoplastic resin, 7.5 parts by mass of a glycidyl group-containing (meth)acrylate copolymer having a high weight average molecular weight (Mw), 0.57 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUC A-1160) manufactured by GE Toshiba Corporation, 0.29 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUC A-189) manufactured by GE Toshiba Corporation as a silane coupling agent, and 0.023 parts by mass of 1-cyanoethyl-2-phenylimidazole (trade name: Curezol 2PZ-CN) manufactured by Shikoku Chemicals Co., Ltd. as a curing accelerator were added to the above resin composition, and the mixture was stirred and mixed. After filtering through a 100-mesh filter, vacuum degassing was performed to prepare a solution of adhesive composition 3(c) having a solid content concentration of 20% by mass. The ratio of each resin component within the total resin content (the combined mass of the thermoplastic resin, thermosetting resin, and crosslinking agent) is: glycidyl-containing (meth)acrylate copolymer: epoxy resin: phenol resin = 27.3% by mass: 50.2% by mass: 22.5% by mass. The inorganic filler content is 18.0% by mass relative to the total resin content.

[0263] (Solution of Adhesive Composition 3(d)) The following adhesive composition 3(d) solution was prepared for use as a general-purpose die-bonding film. First, cyclohexanone was added as a solvent to a resin composition consisting of 54 parts by mass of a cresol novolac epoxy resin (trade name: YDCN-700-10, epoxy equivalent weight: 210, softening point: 80°C) manufactured by Tohto Kasei Co., Ltd. as a thermosetting resin, 46 parts by mass of a phenol resin (trade name: Milex XLC-LL, hydroxyl equivalent weight: 175, water absorption: 1.8%) manufactured by Mitsui Chemicals, Inc. as a crosslinking agent, and 32 parts by mass of silica (trade name: Aerosil R972, average particle size: 0.016 μm) manufactured by Japan Aerosil Co., Ltd. as an inorganic filler. The mixture was stirred and dispersed using a bead mill for 90 minutes.

[0264] Next, 274 parts by mass of a glycidyl group-containing (meth)acrylate copolymer as a thermoplastic resin, 5.0 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUC A-1160) manufactured by GE Toshiba Corporation, 1.7 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUC A-189) manufactured by GE Toshiba Corporation as a silane coupling agent, and 0.1 part by mass of 1-cyanoethyl-2-phenylimidazole (trade name: Curezol 2PZ-CN) manufactured by Shikoku Chemicals Co., Ltd. as a curing accelerator were added to the above resin composition and stirred and mixed. The mixture was filtered through a 100-mesh filter and vacuum degassed to prepare a solution of adhesive composition 3(d) having a solid content concentration of 20% by mass. The ratio of each resin component within the total resin content (the combined mass of the thermoplastic resin, thermosetting resin, and crosslinking agent) is: glycidyl-containing (meth)acrylate copolymer: epoxy resin: phenol resin = 73.3% by mass: 14.4% by mass: 12.3% by mass. The inorganic filler content is 8.6% by mass relative to the total resin content.

[0265] 4. Production of Dicing Tape 10 and Die-Bond Film 20 (Example 1) A solution of the active energy ray-curable acrylic adhesive composition (a) was applied to the release-treated surface of a release liner (polyethylene terephthalate film, 38 μm thick) so that the thickness of the adhesive layer 2 after drying would be 8 μm. After the solvent was dried by heating at 100°C for 3 minutes, the first layer side of the substrate film 1 (a) was laminated onto the adhesive layer 2 to produce the original film of the dicing tape 10. The original film of the dicing tape 10 was then stored at 23°C for 96 hours to crosslink and cure the adhesive layer 2.

[0266] Next, a solution of adhesive composition 3(a) for forming a bonding film (adhesive layer) 3 was prepared. This solution of adhesive composition 3(a) was applied to the release-treated surface of a release liner (polyethylene terephthalate film, 38 μm thick) so that the thickness of the bonding film (adhesive layer) 3 after drying would be 50 μm. The solvent was dried by heating in two steps: first at 90°C for 5 minutes and then at 140°C for 5 minutes. This produced a bonding film (adhesive layer) 3 with a release liner. Furthermore, a protective film (e.g., polyethylene film) could be attached to the dried surface of the bonding film (adhesive layer) 3, if desired.

[0267] Next, the prepared die-bonding film (adhesive layer) 3 with a release liner was cut into a circular shape with a diameter of 335 mm. The exposed adhesive layer surface (the surface without the release liner) of the die-bonding film (adhesive layer) 3 was then laminated to the adhesive layer 2 of the dicing tape 10, from which the release liner had been removed. Lamination conditions were 23°C, 10 mm / second, and a linear pressure of 30 kgf / cm.

[0268] Finally, by cutting the dicing tape 10 into a circle with a diameter of 370 mm, a dicing die-bonding film 20 (DDF(a)) is produced, in which a circular die-bonding film (adhesive layer) 3 with a diameter of 335 mm is laminated on the center of the adhesive layer 2 of the circular dicing tape 10 with a diameter of 370 mm.

[0269] (Examples 2 to 8) The dicing die-bonding films 20 (DDF(b) to DDF(h)) were prepared in the same manner as in Example 1 except that the base film 1(a) was changed to the base films 1(b) to 1(h) shown in Tables 1 to 2, respectively.

[0270] (Examples 9 to 23) The dicing die-bonding films 20 (DDF(i) to DDF(w)) were prepared in the same manner as in Example 2 except that the solution of the active energy ray-curable acrylic adhesive composition 2(a) was replaced with the solutions of the active energy ray-curable acrylic adhesive compositions 2(b) to 2(p) shown in Tables 3 to 6, respectively.

[0271] (Example 24) The cutting solid crystal film 20 (DDF(x)) is prepared in the same manner as in Example 2 except that the solution of the adhesive composition 3(a) is changed to the solution of the adhesive composition 3(b) and the thickness of the solid crystal film (adhesive layer) 3 after drying is changed to 30 μm.

[0272] (Example 25) The dicing die-bonding film 20 (DDF(y)) was prepared in the same manner as in Example 2 except that the solution of the adhesive composition 3(a) was changed to the solution of the adhesive composition 3(c).

[0273] (Example 26) The cutting solid crystal film 20 (DDF(z)) is prepared in the same manner as in Example 2 except that the solution of the adhesive composition 3(a) is changed to the solution of the adhesive composition 3(d) and the thickness of the solid crystal film (adhesive layer) 3 after drying is changed to 20 μm.

[0274] (Comparative Example 1) The cutting die-bonding film 20 (DDF(aa)) is prepared in the same manner as in Example 1 except that the substrate film 1(a) is changed to the substrate film 1(i), the solution of the active energy ray-curing acrylic adhesive composition 2(a) is changed to the solution of the active energy ray-curing acrylic adhesive composition 2(q) shown in Table 8, and the solution of the adhesive composition 3(a) is changed to the solution of the adhesive composition 3(c).

[0275] (Comparative Example 2) The cutting die-bonding film 20 (DDF(bb)) was prepared in the same manner as in Comparative Example 1 except that the base film 1(a) was changed to the base film 1(j) and the solution of the adhesive composition 3(c) was changed to the solution of the adhesive composition 3(a).

[0276] (Comparative Example 3) A dicing die bonding film 20 (DDF(cc)) was produced in the same manner as in Comparative Example 2 except that the base film 1(a) was changed to the base film 1(k).

[0277] (Comparative Example 4) A dicing die-bonding film 20 (DDF(dd)) was prepared in the same manner as in Comparative Example 1 except that the solution of the active energy ray-curable acrylic adhesive composition 2(q) was replaced with the solution of the active energy ray-curable acrylic adhesive composition 2(r) shown in Table 8.

[0278] (Comparative Examples 5 to 7) The dicing die-bonding films 20 (DDF(ee) to DDF(gg)) were prepared in the same manner as in Example 2 except that the solution of the active energy ray-curable acrylic adhesive composition 2(a) was changed to the solutions of the active energy ray-curable acrylic adhesive compositions 2(s) to 2(u) shown in Table 9.

[0279] 5. Determination of adhesion of dicing tape after UV irradiation and shear viscosity of die-bonding film The adhesion of the dicing tapes 10 after UV irradiation and the shear viscosity of the die-bonding films 3 prepared in Examples 1 to 26 and Comparative Examples 1 to 7 were measured by the following method.

[0280] 5.1 Determination of the Adhesion Strength of the Adhesive Layer 2 of the Dicing Tape 10 after Aerobic Ultraviolet Irradiation and the Adhesion Strength of the Adhesive Layer 2 of the Dicing Tape 10 to the Die-bonding Film (Adhesive Layer) 3 after Oxygen-Free Ultraviolet Irradiation For the dicing tapes 10 prepared in Examples 1-26 and Comparative Examples 1-7, the adhesive strength A of the adhesive layer 2 after ultraviolet irradiation in the presence of oxygen and the adhesive strength B after ultraviolet irradiation in the absence of oxygen were measured by the following method.

[0281] 5.1.1 Adhesion after UV irradiation in oxygen environment A First, cut the dicing tape 10 into a size of 25 mm in width (TD direction of the substrate film 1) and 120 mm in length (MD direction of the substrate film 1). Next, the adhesive layer side of the dicing tape 10, from which the release liner had been removed, was irradiated with ultraviolet (UV) light with a central wavelength of 367 nm (irradiation intensity: 70 mW / cm², integrated radiation: 150 mJ / cm²) using a metal halide lamp. The dicing tape 10 was then pressed and bonded neatly to a stainless steel plate (SUS304・BA plate) from the edge of the adhesive layer side using a 2 kg rubber roller. The roller was moved back and forth once at a speed of approximately 5 mm / second in an environment of 23°C and 50% RH. This was used as a test piece for measurement. After 20 minutes of undisturbed rest, the test pieces were subjected to a 90° peel angle (unit: N / 25mm) test of the dicing tape 10 to a stainless steel plate (SUS304・BA plate) using a peel angle-free adhesive / film peeling analyzer (Figure 4) in an environment with a temperature of 23°C and a humidity of 50%. The peel speed was set at 300 mm / minute. The test pieces were tested on three specimens, and the average of the three values ​​was used as the adhesion strength (A) of the dicing tape 10 after UV irradiation in the presence of oxygen.

[0282] 5.1.2 Adhesion after UV irradiation in the absence of oxygen B First, cut the dicing tape 10 into a size of 25 mm in width (TD direction of the substrate film 1) and 120 mm in length (MD direction of the substrate film 1). Next, a 2 kg rubber roller was used to press and bond the adhesive layer of the dicing tape 10, from the end of the release liner, to a stainless steel plate (SUS304 BA plate). The roller was moved back and forth at a speed of approximately 5 mm / second in an environment of 23°C and 50% RH, ensuring uniform lamination. After allowing the tape to rest for 20 minutes, the dicing tape 10 was irradiated with ultraviolet (UV) light with a central wavelength of 367 nm (irradiation intensity: 70 mW / cm², integrated radiation: 150 mJ / cm²) from the substrate film 1 side using a metal halide lamp to prepare a test piece for measurement. For this test piece, similar to the measurement of adhesion strength (A) after UV irradiation in the presence of oxygen, the adhesion strength (unit: N / 25mm) of the dicing tape 10 at a peel angle of 90° was measured using the peel angle-free adhesive / film peeling analyzer shown in Figure 4. The peel speed was set at 300 mm / minute. The measurement was performed on three test pieces, and the average of the three values ​​was used as the adhesion strength (B) of the dicing tape 10 after UV irradiation in the absence of oxygen.

[0283] Furthermore, using the measured values ​​of the adhesive strength, the ratio A / B of the adhesive strength A of the adhesive layer 2 of the dicing tape 10 after ultraviolet irradiation in the presence of oxygen to the adhesive strength B after ultraviolet irradiation in the absence of oxygen was calculated.

[0284] 5.2 Determination of Shear Viscosity of Die-bonding Film (Adhesive Layer) 3 at 80°C The shear viscosity at 80°C of each bonding film (adhesive layer) 3 formed from solutions of adhesive compositions 3(a) to 3(d) was measured using the following method. After removing the release liner, multiple bonding films (adhesive layers) 3 were laminated at 70°C to a total thickness of 200 to 210 μm. This laminate was then punched out in the thickness direction to a size of 10 mm x 10 mm to prepare a measurement sample. A dynamic viscoelasticity instrument (ARES) (manufactured by Rheometric Scientific FE) was then used, fitted with an 8 mm diameter circular aluminum plate jig, and the measurement sample was set. While applying a 5% deformation to the measurement sample at 35°C, the shear viscosity was measured while the sample was heated at a rate of 5°C / minute. The shear viscosity at 80°C was determined.

[0285] The dicing tapes 10 and dicing die-bonding films 20 produced in Examples 1 to 26 and Comparative Examples 1 to 7 have their respective configurations and the aforementioned measurement results shown in Tables 1 to 9.

[0286]

[0287]

[0288]

[0289]

[0290]

[0291]

[0292]

[0293]

[0294]

[0295] 6. Evaluation of the assembly of dicing tape The dicing tapes 10 prepared in Examples 1-26 and Comparative Examples 1-7 were evaluated using the following method in the state of dicing the die-bonding films 20 (DDF(a)-DDF(gg)).

[0296] 6.1 Die-bonding film (adhesive layer) cutting properties First, a semiconductor wafer W (mirror-finished silicon wafer, 750 μm thick, 12-inch outer diameter) was prepared, and commercially available back-grinding tape was attached to one side. Next, a laser saw (DFL7361, manufactured by Disco Co., Ltd.) was used to irradiate the semiconductor wafer W from the side opposite the back-grinding tape, emitting laser light along the grid-like planned cutting lines under the following conditions, so that the semiconductor wafers 30a would be cut to a size of 4.6 mm x 7.2 mm. This formed modified regions 30b at specific depths on the semiconductor wafer W.

[0297] Laser irradiation conditions (1) Laser oscillator type: semiconductor laser excited Q-switched solid-state laser (2) Wavelength: 1342nm (3) Oscillation form: pulse (4) Frequency: 90kHz (5) Output: 1.7W (6) Moving speed of semiconductor wafer stage: 700 mm / s

[0298] Next, using a back grinding apparatus (DGP8761) manufactured by Disco Co., Ltd., the 750 μm-thick semiconductor wafer W with the modified region 30 b formed thereon, held on back grinding tape, was ground and thinned to obtain 30 μm-thick individual semiconductor wafers 30 a. A cold expansion step was then performed using the following method to evaluate the cleavage properties of the die-bonding film (adhesive layer). Specifically, a 30 μm thick semiconductor wafer 30a was laminated to the surface opposite to the side on which the back grinding tape was applied, using a lamination device (DFM2800) manufactured by Disco Co., Ltd., by laminating the die bonding film 20 at a lamination temperature of 70°C and a lamination speed of 10 mm / second. The die bonding film 3, exposed by peeling off the release liner from the dicing die bonding film 20 produced in each of the Examples and Comparative Examples, was then laminated to the semiconductor wafer 30a. A ring frame (wafer ring) 40 was attached to the exposed portion of the adhesive layer 2 at the outer edge of the dicing tape 10, and the back grinding tape was then removed. The dicing die bonding film 20 was attached to the semiconductor wafer 30a so that the MD direction of the base film 1 aligned with the longitudinal direction of the grid-like dividing lines of the semiconductor wafer 30a (the TD direction of the base film 1 aligned with the transverse direction of the grid-like dividing lines of the semiconductor wafer 30a).

[0299] The laminate (semiconductor wafer 30 / bonding film 3 / adhesive layer 2 / base film 1) containing the semiconductor wafer 30a, held on the aforementioned ring frame (wafer ring) 40, is mounted on a spreading device (DDS2300 Fully Automatic Die Separator) manufactured by Disco Co., Ltd. Next, the dicing tape 10 (adhesive layer 2 / base film 1) used to sever the die-bonding film 20 with the semiconductor wafer 30a is cold-spread under the following conditions, thereby severing the die-bonding film 3. This results in the semiconductor wafer 30a with the die-bonding film (adhesive layer) 3 attached. While the cold-spreading step is performed under the following conditions in this embodiment, any cold-spreading step can be performed by appropriately adjusting the spreading conditions (such as the "spreading speed" and "spreading amount") based on the physical properties of the base film 1 and temperature conditions.

[0300] ･Conditions for the cold expansion step Temperature: -15℃, cooling time: 80 seconds, Expansion speed: 300mm / s, Extension: 11mm, (4) Standby time: 0 seconds

[0301] The cold-expanded die-bonding film (adhesive layer) 3 was observed from the front side of the semiconductor wafer 30a using an optical microscope (model: VHX-1000, manufactured by Keyence Co., Ltd.) at 200x magnification to measure the number of uncut edges among the edges scheduled for cutting. The ratio of the number of cut edges to the total number of uncut edges was then calculated as the cutting rate (%). The optical microscope observation was performed on all semiconductor wafers 30a with the die-bonding film 3a attached. The cutting properties of the die-bonding film (adhesive layer) 3 were evaluated according to the following criteria; a rating of B or higher was considered good.

[0302] A: The cutting rate is 95% or more and 100% or less. B: The cutting rate is above 90% but less than 95%. C: The cutting rate is above 85% and below 90%. D: The cutting rate is less than 85%.

[0303] 6.2 Confirmation of the Edge Peeling of the Die-bonding Film and Calculation of the Ratio of the Area S1 of the Edge Peeling from the Adhesive Layer After the cold expansion process was completed, the expansion device (DDS2300 Fully Automatic Die Separator) manufactured by Disco Co., Ltd. was used again with its hot expansion unit to perform the room temperature expansion process under the following conditions.

[0304] ･Conditions for room temperature expansion step Temperature: 23℃ Expansion speed: 30mm / s, Extension: 9mm, (4) Standby time: 15 seconds

[0305] Next, while maintaining the expanded state, the dicing tape 10 is adsorbed onto the adsorption table. While maintaining this adsorption, the table is lowered as it progresses. A heat shrinking step is then performed under the following conditions, whereby the circumferential portion of the dicing tape 10 outside the semiconductor wafer 30a holding area is heated and shrunk (heat shrinkage).

[0306] ･Conditions for heat shrinking step Hot air temperature: 200℃, Air volume: 40L / min, distance between hot air outlet and cutting tape: 20mm, Stage rotation speed: 7° / second

[0307] After releasing the dicing tape 10 from the suction table, the peeling of the bonding film (adhesive layer) 3 from the adhesive layer 2 of the dicing tape 10 was observed at 50x magnification on all four sides of the individual semiconductor wafers 30a, from the back side (base film 1 side) of the semiconductor wafers 30a, using an optical microscope (model: VHX-1000) manufactured by Keyence Co., Ltd. Because the peeling of the bonding film (adhesive layer) 3 was observed to be substantially the same regardless of the position of the semiconductor wafer 30a, the presence of peeling was confirmed for 20 specific semiconductor wafers 30a with the bonding film 3a attached, located in the center of the semiconductor wafer 30. The ratio of area S1 was calculated using the following method. First, three random images of the 20 semiconductor wafers 30a with die-bonding films 3a were selected. Using the image processing software "ImageJ" (available at https: / / imagej.Nih.gov / ij / ), the images corresponding to area S1 and area S2 were binarized. The binarized images were then averaged to determine the ratio of area S1 of the edge of the die-bonding film 3a on the small wafer that had been peeled from the adhesive layer 2 relative to the total area of ​​the die-bonding film 3a on the small wafer (= S1 + S2).

[0308] 6.3 Pickup Evaluation samples were prepared by irradiating the adhesive layer 2 with ultraviolet (UV) light having a central wavelength of 367 nm at an intensity of 70 mW / cm² and a cumulative radiation dose of 150 mJ / cm² from the base film 1 side of the dicing tape 10 holding the semiconductor wafer 30a with the die-bonding film (adhesive layer) 3a, which had been cut and singulated by the above-described expansion step, to cure the adhesive layer 2.

[0309] Next, a pickup test of semiconductor wafers 30a with die-bonding films 3a was conducted using a pickup device (Die Bonder DB-830P) manufactured by FASFORD TECHNOLOGY Co., Ltd. (formerly Hitachi Advanced Technology Co., Ltd.). The pickup collet dimensions were 4.5 x 7.1 mm, the number of push-up pins was 12, and the pickup conditions were set at a push-up speed of 5 mm / s and push-up heights of 300 μm, 200 μm, and 150 μm. Twenty singulated wafers (wafers) were picked up continuously at specific locations, and the number of successfully picked-up wafers was calculated. The pickup performance of semiconductor wafers 30a with die-bonding films 3a at various push-up heights was evaluated according to the following criteria.

[0310] A: 20 wafers are picked up continuously, and the number of wafers picked up without breakage or mispickup (number of successful picks) is 19 or more and 20 or less (success rate 95% or more and 100% or less). B: 20 ​​wafers are picked up continuously, and the number of wafers picked without breakage or mispickup (number of successful picks) is 17 or more and less than 19 (success rate is 85% or more and less than 95%). C: 20 wafers were picked up continuously without any wafer breakage or picking errors (number of successful picks) reaching less than 17 (success rate less than 85%).

[0311] As a comprehensive evaluation of the above-mentioned pickup test, the number of semiconductor chips 30a with a die-bonding film 3a that were successfully picked up is evaluated as follows: the smaller the push-up height of the push-up pin A or B is, the better the pickup performance when using the dicing tape 10 is judged to be.

[0312] 6.3. Evaluation results The results of the evaluation of the die-bonding films 20 (DDF(a) to DDF(gg)) of the dicing tapes 10 produced in Examples 1 to 26 and Comparative Examples 1 to 7 are shown in Tables 10 to 18.

[0313]

[0314]

[0315]

[0316]

[0317]

[0318]

[0319]

[0320]

[0321]

[0322] As shown in Tables 10 to 16, the dicing die-bonding films 20 (DDF(a) to DDF(z)) of Examples 1 to 26 were prepared using a dicing tape 10 having a base film 1(a) to 1(h) that meets the requirements of the present invention and an adhesive layer 2 containing adhesive compositions 2(a) to 2(p), and the adhesive layer 2 meeting the requirements of adhesion strength A after ultraviolet irradiation in the presence of oxygen and adhesion strength B after ultraviolet irradiation in the absence of oxygen. When supplied to the manufacturing steps of semiconductor devices, it was confirmed that the die-bonding film 3 was well cut by cold expansion, and the cut die-bonding film In 3a, the edge portion (the four surrounding portions) is in a state of being moderately peeled off from the adhesive layer 2 of the dicing tape 10. By greatly reducing the adhesion A after ultraviolet irradiation under oxygen, the edge portion of the solid crystal film 3 in the state of being peeled off from the above-mentioned adhesive layer is greatly suppressed during picking up, and is strongly re-fixed to the adhesive layer 2 of the dicing tape 10 after ultraviolet irradiation. The semiconductor chip 30a with the dicing solid crystal film 3a is pushed up and peeled off from the adhesive layer 2 smoothly starting from the edge portion, and better results are also obtained in the evaluation of the picking property.

[0323] A detailed comparison of the examples reveals that the dicing of the die-bonding film 20 in Examples 2-4, 6, 8, 10, 11, 14-16, 21, 22, and 24-26 demonstrates both high and excellent performance in both the cutting and pick-up properties of the die-bonding film 3. Specifically, the cutting rate of the die-bonding film 3 during the cold expansion step was extremely good, and the yield rate in the pick-up test with a small push-up height was also very good.

[0324] The dicing die-bonding films 20 of Examples 1 and 7 exhibited slightly inferior cutting and pick-up properties compared to the dicing die-bonding films 20 of Examples 2-4, 6, and 8, because the average elastic modulus (Y MD + Y TD) / 2 of the substrate films 1(a) and 1(g) at 5% elongation in the MD and TD directions at 0°C was close to the lower limit of the present invention. On the other hand, the dicing die-bonding film 20 of Example 5 exhibited slightly inferior pick-up properties compared to the dicing die-bonding films 20 of Examples 2-4, 6, and 8, because the average elastic modulus (Y MD + Y TD) / 2 of the substrate film 1(e) at 5% elongation in the MD and TD directions at 0°C was close to the upper limit of the present invention.

[0325] In the cut die-bonding films 20 of Examples 9 and 18, since the hydroxyl value of the acrylic adhesive polymer (A) of the adhesive composition 2(a) is close to the lower limit of the range of the present invention, and the amount of the polyisocyanate cross-linking agent added is also at the lower limit of the range of the present invention, compared with the cut die-bonding films 20 of Examples 2, 10, and 11, the proportion of the area S1 of the edge portion (oblique line portion) of the small piece of die-bonding film 3a peeled off from the adhesive layer 2 during cold expansion is slightly smaller, that is, the contribution of the effect of reducing the adhesion after ultraviolet irradiation under oxygen is small, and the pickup property is slightly poor.

[0326] In the case of the cutting die-bonding films 20 of Examples 12, 17, and 19, the hydroxyl value of the acrylic adhesive polymer (A) of the adhesive composition 2(a) is close to the lower limit of the range of the present invention, and the amount of the polyisocyanate cross-linking agent added is also close to the upper limit of the range of the present invention, or is the upper limit, and the amount of the polyisocyanate cross-linking agent added in the adhesive composition 2(a) and the isocyanate group of the polyisocyanate cross-linking agent are close to the upper limit of the range of the present invention. The equivalent ratio (-NCO / -OH) of the hydroxyl group (-NCO) to the hydroxyl group (-OH) of the acrylic adhesive polymer is also close to the upper limit of the present invention's range. Therefore, compared to the dicing die-bonding films 20 of Examples 2, 10, and 11, the area S1 of the edge portion (hatched area) of the small die-bonding film 3a peeled from the adhesive layer 2 during cold expansion is slightly larger. The effect of reducing adhesion after ultraviolet irradiation in the presence of oxygen is gradually suppressed due to the increased reattachment area, resulting in slightly poor pickup performance. Furthermore, the dicing die-bonding films 20 of Examples 12 and 19 also exhibit slightly poorer cutting performance of the die-bonding film 3.

[0327] In the cut die-bonding film 20 of Example 13, the hydroxyl value of the acrylic adhesive polymer (A) of the adhesive composition 2(a) is close to the lower limit of the range of the present invention. In addition, the amount of the polyisocyanate crosslinking agent added is also at the lower limit of the range of the present invention. Compared with the cut die-bonding films 20 of Example 2 and Examples 14 to 17, the area S1 of the edge portion (oblique line portion) of the small piece of die-bonding film 3a peeled off from the adhesive layer 2 during cold expansion is slightly smaller, that is, the contribution of the adhesive force reduction effect after ultraviolet irradiation under oxygen is small, and the pickup property is slightly poor.

[0328] The adhesion of the cutting die-bonding films 20 of Examples 20 and 23 after ultraviolet irradiation in oxygen is close to the upper limit of the range of the present invention. Compared with the cutting die-bonding films 20 of Examples 2, 21, and 22, the pickup properties are slightly worse.

[0329] In contrast, as shown in Tables 17 and 18, the dicing bonding films 20 (DDF(aa) to DDF(gg)) of Comparative Examples 1 to 7, which were produced using a dicing tape 10 that did not meet at least any of the requirements for the properties of the base film 1, the adhesive composition, and the adhesion strength A of the adhesive layer 2 after ultraviolet irradiation in the presence of oxygen and the adhesion strength B after ultraviolet irradiation in the absence of oxygen, were confirmed to have worse results than the dicing bonding films 20 (DDF(a) to DDF(z)) of Examples 1 to 26 in either the evaluation of the cutting properties of the bonding film 3 in the cold expansion step or the pickup properties in the pickup step.

[0330] Specifically, the average elastic modulus (Y MD + Y TD) / 2, the amount of the polyisocyanate crosslinking agent added in the adhesive composition 2(q), and the equivalent ratio (-NCO / -OH) of the isocyanate group (-NCO) of the polyisocyanate crosslinking agent to the hydroxyl group (-OH) of the acrylic adhesive polymer are below the lower limit of the range of the present invention. Therefore, the cutting property of the solid-state film 3 composed of the adhesive composition 3(c) in the cold expansion step is poor. In the cut solid-state film 3a, the edge portion thereof does not form a state of being peeled off from the adhesive layer 2 (no peeling is observed). Compared with the cut solid-state film 20 (DDF(y)) of Example 25 using the solid-state film 3 composed of the adhesive composition 3(c), poor results were confirmed in both the evaluation of the cutting property and the pickup property of the solid-state film 3 composed of the adhesive composition 3(c).

[0331] Similarly, for the dicing die bonding films 20 (DDF(bb)) and (DDF(cc)) of Comparative Examples 2 and 3, the average values ​​of the elastic modulus (Y MD + Y TD) / 2, the amount of the polyisocyanate crosslinking agent added in the adhesive composition 2(q), and the equivalent ratio (-NCO / -OH) of the isocyanate group (-NCO) of the polyisocyanate crosslinking agent to the hydroxyl group (-OH) of the acrylic adhesive polymer were also below the lower limit of the range of the present invention. Therefore, the die-bonding film 3 composed of the adhesive composition 3(a) had poor cutting properties in the cold expansion step, and the edge portion of the cut die-bonding film 3a did not form a state of peeling from the adhesive layer 2 (no peeling was observed). For example, compared with the cut die-bonding films 20 (DDF(a) to DDF(q)) and (DDF(t) to DDF(w)) of Examples 1 to 17 and 20 to 23, poor results were confirmed in both the cutting property and the pickup property evaluation of the die-bonding film 3 composed of the adhesive composition 3(a).

[0332] Furthermore, with respect to the dicing die-bonding film 20 (DDF (dd)) of Comparative Example 4, although the adhesive composition 2 (a) of the dicing tape 10 meets the requirements of the present invention, the average value (Y MD + Y TD) / 2 of the elastic modulus of the base film 1 (i) at 5% elongation in the MD and TD directions at 0°C is lower than the lower limit of the range of the present invention, and the adhesion A of the adhesive layer 2 after ultraviolet irradiation in the presence of oxygen exceeds the upper limit of the range of the present invention. Therefore, the die-bonding film 3 composed of the adhesive composition 3 (a) has poor cutting properties in the cold expansion step. Although the four corners of the cut die-bonding film 3a are slightly peeled from the adhesive layer 2, the adhesion A after ultraviolet irradiation in the presence of oxygen is large. For example, compared with the dicing die-bonding film 20 (DDF (g)) of Example 7, the die-bonding film 3 composed of the adhesive composition 3 (a) has poor results in both the cutting properties and the pickup properties.

[0333] Furthermore, regarding the dicing die bonding film 20 (DDF(ee)) of Comparative Example 5, although the base film 1(b) of the dicing tape 10 meets the requirements of the present invention, the amount of the polyisocyanate crosslinking agent added in the adhesive composition 2(s) and the isocyanate groups of the polyisocyanate crosslinking agent are not sufficient. The equivalent ratio (-NCO / -OH) of the hydroxyl group (-NCO) to the hydroxyl group (-OH) of the acrylic adhesive polymer is lower than the lower limit of the range of the present invention. Therefore, although the cutting property of the solid-state film 3 composed of the adhesive composition 3 (a) in the cold expansion step is good, the edge portion of the cut solid-state film 3a does not form a state of peeling from the adhesive layer 2 (no peeling is observed). For example, compared with the cut solid-state film 20 (DDF (i)) of Example 9, a slightly worse result was confirmed in the evaluation of the pickup property.

[0334] Furthermore, with respect to the cutting solid crystal film 20 (DDF(ff)) of Comparative Example 6, although the properties of the base film 1 (b) and the adhesive composition 2 (t) of the cutting tape 10 meet the requirements of the present invention, the adhesion A of the adhesive layer 2 after ultraviolet irradiation under oxygen exceeds the upper limit of the range of the present invention. Therefore, although the cutting property of the solid crystal film 3 composed of the adhesive composition 3 (a) in the cold expansion step is good, in the cut solid crystal film 3a, its edge portion (the four surrounding portions) is moderately peeled off from the adhesive layer 2 of the cutting tape 10, but the adhesion A after ultraviolet irradiation under oxygen is large. For example, compared with the cutting solid crystal film 20 (DDF(p)) of Example 16, a poor result was confirmed in the evaluation of the pickup property.

[0335] Furthermore, with respect to the dicing die-bonding film 20 (DDF (gg)) of Comparative Example 7, although the requirements of the present invention regarding the adhesion strength A after ultraviolet irradiation in the presence of oxygen and the adhesion strength B after ultraviolet irradiation in the absence of oxygen of the base film 1 (b) and the adhesive layer 2 of the dicing tape 10 are met, the amount of the polyisocyanate crosslinking agent added in the adhesive composition 2 (u) and the equivalent ratio (-NCO / -OH) of the isocyanate group (-NCO) of the polyisocyanate crosslinking agent to the hydroxyl group (-OH) of the acrylic adhesive polymer exceed the upper limit of the range of the present invention. Therefore, the following While the bonding film 3 composed of adhesive composition 3(a) could be cut without any problems during the cold expansion step, the cut bonding film 3a exhibited excessive and irregular peeling from the adhesive layer 2 of the dicing tape 10 from its edges (peripheral portions) toward the center. During pickup, the bonding film 3a, which had been peeled from the adhesive layer, exhibited an excessively large area of ​​reattachment to the adhesive layer 2 after ultraviolet irradiation on the dicing tape 10. For example, poor pickup performance was observed compared to the dicing bonding film 20 (DDF(1)) of Example 12. Furthermore, after the expansion step, cracking of a portion of the adhesive layer 2 or curling of the base film 1 was observed.

[0336] 1: Base film 2: Adhesive layer 3,3a1,3a2: Die-bonding film (adhesive layer, adhesive film) 4: Stainless steel plate (SUS304 BA plate) 5: Flat cross stage 6: Actuator 7: Dynamometer 8: Rotating stage 9: Semiconductor chip with die-bonding film 10: Cutting tape 20: Cutting the die-bonding film W,30:Semiconductor wafer 30a, 30a1, 30a2: semiconductor wafers 30b: Modified area (cutting area in Figures 7(c) to (f) and 8(a) and (b)) 30c: Semiconductor wafer cutting line 31: Center of semiconductor wafer 32: Left side of semiconductor wafer 33: Right side of semiconductor wafer 34: Top of semiconductor wafer 35: Lower part of semiconductor wafer 40: Ring frame (wafer ring) 41: Retainer 50: Adsorption claw 60: Pushing needle 70,80:Semiconductor devices 71,81:Semiconductor wafer mounting support substrate 72: External connection terminal 73:Terminal 74,84: Wire 75,85: Sealing material 76: Support components

Claims

1. A cutting tape comprising a substrate film and an adhesive layer on the substrate film containing an active energy line curable adhesive composition, wherein the substrate film has an elastic modulus of YMD when stretched by 5% in the MD direction (the flow direction during film formation) at 0°C and an elastic modulus of YTD when stretched by 5% in the TD direction (a direction perpendicular to the MD direction) at 0°C, and the average value of the elastic modulus at 5% elongation (YMD+YTD) / 2 is in the range of 165 MPa or more and 260 MPa or less; the active energy line curable adhesive composition contains an acrylic adhesive polymer having active energy line reactive carbon-carbon double bonds and hydroxyl groups, a photopolymerization initiator, and a polyisocyanate crosslinking agent that crosslinks with the aforementioned hydroxyl groups. The aforementioned acrylic adhesive polymer has a hydroxyl value in the range of 12.0 mg KOH / g or more and 40.5 mg KOH / g or less. The aforementioned polyisocyanate crosslinking agent contains 2.4 parts by weight or more and 7.0 parts by weight or less relative to 100 parts by weight of the aforementioned acrylic adhesive polymer. The equivalent ratio (-NCO / -OH) of the isocyanate groups (-NCO) in the aforementioned polyisocyanate crosslinking agent to the hydroxyl groups (-OH) in the aforementioned acrylic adhesive polymer is adjusted in the range of 0.14 or more and 1.32 or less. The adhesive layer of the aforementioned cutting tape, after being exposed to ultraviolet light under oxygen at 23°C, exhibits an adhesion strength A (ultraviolet integrated light intensity: 150mJ / m2, peel angle: 90°, peel speed: 300mm / min) of less than 3.50N / 25mm. Similarly, after being exposed to ultraviolet light under oxygen-free conditions at 23°C, the adhesion strength B (ultraviolet integrated light intensity: 150mJ / m2, peel angle: 90°, peel speed: 300mm / min) of more than 0.25N / 25mm and less than 0.70N / 25mm.

2. The cutting tape of claim 1, wherein the aforementioned substrate film is a resin film composed of a resin composition containing an ionic polymer of ethylene / unsaturated carboxylic acid copolymer (IO) and polyamide resin (PA).

3. The cutting tape of claim 1 or 2, wherein the aforementioned active energy line curing adhesive composition contains at least three systems of photopolymerization initiators, namely, α-aminoalkylphenyl ketone photopolymerization initiator (a), alkylphenyl ketone photopolymerization initiator other than α-aminoalkylphenyl ketone photopolymerization initiator (b), and acetylsphosphine oxide photopolymerization initiator (c), as the aforementioned photopolymerization initiator.

4. The cutting tape of claim 3, wherein the respective contents of the aforementioned α-aminoalkylphenyl ketone photopolymerization initiator (a), alkylphenyl ketone photopolymerization initiator other than α-aminoalkylphenyl ketone photopolymerization initiator (b), and acetylenol oxide photopolymerization initiator (c), relative to 100 parts by weight of the aforementioned acrylic adhesive polymer, are as follows: α-aminoalkylphenyl ketone photopolymerization initiator (a) is 0.8 parts by weight or more and 5.0 parts by weight; alkylphenyl ketone photopolymerization initiator other than α-aminoalkylphenyl ketone photopolymerization initiator (b) is 0.2 parts by weight or more and 5.0 parts by weight; and acetylenol oxide photopolymerization initiator (c) is 0.2 parts by weight or more and 2.0 parts by weight.

5. The cutting tape as requested in item 1 or 2, wherein the ratio A / B of the aforementioned adhesive strength A after ultraviolet irradiation under oxygen to adhesive strength B after ultraviolet irradiation under anaerobic conditions is in the range of 3.00 or more and 5.00 or less.

6. The cutting tape of claim 1 or 2, wherein the cutting tape is used to extend (stretch) a sheet-like composite on which a die-bonding film and a plurality of monolithic semiconductor wafers are sequentially laminated on the adhesive layer at a temperature of -30°C to 0°C, and to cut the die-bonding film in accordance with the shape of the monolithic semiconductor wafer.

7. The cutting tape of claim 6, wherein the cutting tape is such that when the cutting tape on which the aforementioned sheet-like laminate is attached is extended (stretched) at a temperature range of -30°C to 0°C and cuts the die bond film in accordance with the shape of the monolithized semiconductor wafer, the edge portion (the four-sided perimeter portion) of the aforementioned die bond film will be peeled off by the adhesive layer.

8. The cutting tape of claim 7, wherein the proportion of the area of ​​the edge portion (square perimeter portion) of the die bond film cut off by the aforementioned adhesive layer in accordance with the shape of the monolithized semiconductor wafer is between 10% and 45% relative to the total area of ​​the cut die bond film.

9. A method for manufacturing a semiconductor device, wherein the cutting tape of any one of claims 1 to 8 is used.

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