Dicing tape, dicing die bonding film, and method for manufacturing semiconductor device

Abstract

The invention relates to a dicing tape, a dicing die bonding film, and a method for manufacturing a semiconductor device. Provided is a dicing tape provided with a base material layer and an adhesive layer superimposed on one surface of the base material layer, the base material layer having a plurality of laminated layers, the plurality of layers having at least a first base material layer containing an ethylene-acrylic acid copolymer resin and a second base material layer containing a resin other than the ethylene-acrylic acid copolymer resin, the second base material layer is disposed between the first base material layer and the adhesive layer.

Description

Technical Field

[0001] The present invention relates to a dicing tape used, for example, when manufacturing a semiconductor device, a dicing die-bonding film including the dicing tape, and a method for manufacturing a semiconductor device using the dicing die-bonding film. Background Art

[0002] Conventionally, dicing die-bonding films used in the manufacture of semiconductor devices and the like are known. Such dicing die-bonding films include, for example, a dicing tape and a die-bonding sheet laminated on the dicing tape and bonded to a semiconductor wafer. The dicing tape includes a base layer and an adhesive layer in contact with the die-bonding sheet. Such dicing die-bonding films are used in the manufacture of semiconductor devices, for example, as described below.

[0003] The method of manufacturing a semiconductor device generally includes the following steps: a front-end step of forming a circuit surface on one side of a circular bare wafer using a highly integrated electronic circuit; and a back-end step of cutting and assembling semiconductor chips from the semiconductor wafer with the circuit surface formed thereon.

[0004] For example, the post-process includes the following steps: a stealth dicing step, in which a laser is used to form a fragile portion in a semiconductor wafer for cutting the semiconductor wafer into small semiconductor chips (chips); a mounting step, in which the surface of the semiconductor wafer opposite the circuit surface is attached to a die bond pad, and the semiconductor wafer is fixed to the dicing tape via the die bond pad; an expansion step, in which the dicing tape is stretched along the radial direction of the semiconductor wafer to cut the semiconductor wafer with the fragile portion formed thereon together with the die bond pad, thereby increasing the spacing between adjacent semiconductor chips (chips); a pickup step, in which the die bond pad is peeled from the adhesive layer to remove the semiconductor chip with the die bond pad attached thereto; a die bonding step, in which the semiconductor chip with the die bond pad attached thereto is bonded to an adherend via the die bond pad; and a curing step, in which the die bond pad attached to the adherend is thermally cured. For example, a semiconductor device is manufactured through these steps.

[0005] In the semiconductor device manufacturing method described above, various problems may arise, for example, after the expansion step. For example, portions of severed semiconductor wafers (i.e., semiconductor chips) and die-bonding sheet pieces may lift from the surface of the adhesive layer of the dicing tape. Furthermore, even if the dicing tape is heated around the severed semiconductor chips to shrink, the tape may relax, causing the stretched tape to return to its original shape, narrowing the temporarily expanded spacing (kerf) between adjacent semiconductor chips.

[0006] On the other hand, in order to solve the former problem, that is, to suppress the floating of semiconductor chips after the expansion process, a dicing tape in which the specific physical properties of the base material layer are designed to fall within a predetermined numerical range is known (for example, Patent Document 1).

[0007] Specifically, in the dicing tape described in Patent Document 1, the base layer is composed of a resin film having a single structure or a laminated structure, the heat shrinkage of the base layer in the MD direction at 100°C is 20% or less, and the bending hardness calculated as the product of the elastic modulus of the base layer and the second moment of area of ​​the base layer measured at 25°C using a nanoindenter is 40 N·mm 2 the following.

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-077753 Summary of the Invention

[0011] Problems to be solved by the invention

[0012] On the other hand, the latter issue has not necessarily been fully studied. In particular, if the heating temperature used to shrink a portion of the dicing tape is low, the stretched portion of the dicing tape may not shrink sufficiently, and the spacing (kerf) between adjacent semiconductor chips may not be adequately maintained.

[0013] Therefore, there is a demand for a dicing tape that can shrink even when heated at a relatively low temperature after being stretched and can sufficiently maintain the spacing distance (kerf) between adjacent semiconductor chips.

[0014] Therefore, an object of the present invention is to provide a dicing tape that can shrink even when heated at a relatively low temperature after being stretched in an expansion step and can sufficiently maintain the spacing distance (kerf) between adjacent semiconductor chips.

[0015] Solutions for solving problems

[0016] In order to solve the above-mentioned problems, the dicing tape of the present invention comprises a base material layer and an adhesive layer superimposed on one side of the base material layer.

[0017] The substrate layer has a plurality of stacked layers, and the plurality of layers include at least a first substrate layer containing an ethylene-acrylic acid copolymer resin and a second substrate layer containing a resin other than the ethylene-acrylic acid copolymer resin.

[0018] The second base layer is disposed between the first base layer and the adhesive layer.

[0019] The dicing die-bonding film according to the present invention includes the dicing tape and a die-bonding sheet superimposed on the dicing tape.

[0020] In the method for manufacturing a semiconductor device according to the present invention,

[0021] A semiconductor device having a semiconductor chip is manufactured using a dicing die-bonding film comprising the dicing tape and a die-bonding sheet superimposed on the dicing tape.

[0022] The method for manufacturing a semiconductor device comprises the following steps:

[0023] a mounting step of placing the die-bonding sheet between the adhesive layer of the dicing tape and the semiconductor wafer, thereby fixing the semiconductor wafer to the dicing tape via the die-bonding sheet; and

[0024] an expansion step of cutting the semiconductor wafer and the die-bonding sheet together by stretching the dicing tape, thereby dividing the semiconductor wafer into small pieces to obtain a semiconductor chip group;

[0025] A portion of the stretched dicing tape is heated around the semiconductor chip group to shrink it. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a cross-sectional view obtained by cutting the dicing die-bonding film of the present embodiment along the thickness direction.

[0027] Figure 2A This is a cross-sectional view obtained by cutting an example of the base material layer of the dicing tape in the dicing die-bonding film of the present embodiment in the thickness direction.

[0028] Figure 2B This is a cross-sectional view obtained by cutting another example of the base material layer of the dicing tape in the dicing die-bonding film of the present embodiment in the thickness direction.

[0029] Figure 3A This is a cross-sectional view schematically showing a stealth dicing step in a method of manufacturing a semiconductor device.

[0030] Figure 3B This is a cross-sectional view schematically showing a stealth dicing step in a method of manufacturing a semiconductor device.

[0031] Figure 3C This is a cross-sectional view schematically showing a stealth dicing step in a method of manufacturing a semiconductor device.

[0032] Figure 3D It is a cross-sectional view schematically showing a backside grinding step in a method for manufacturing a semiconductor device.

[0033] Figure 4A It is a cross-sectional view schematically showing a mounting step in a method of manufacturing a semiconductor device.

[0034] Figure 4B It is a cross-sectional view schematically showing a mounting step in a method of manufacturing a semiconductor device.

[0035] Figure 5A This is a cross-sectional view schematically showing a low-temperature expansion step in a method for manufacturing a semiconductor device.

[0036] Figure 5B This is a cross-sectional view schematically showing a low-temperature expansion step in a method for manufacturing a semiconductor device.

[0037] Figure 5C This is a cross-sectional view schematically showing a low-temperature expansion step in a method for manufacturing a semiconductor device.

[0038] Figure 6A This is a cross-sectional view schematically showing an expansion step at room temperature in a method for manufacturing a semiconductor device.

[0039] Figure 6B This is a cross-sectional view schematically showing an expansion step at room temperature in a method for manufacturing a semiconductor device.

[0040] Figure 7 This is a schematic diagram showing a state of heat treatment during an expansion step in a method of manufacturing a semiconductor device, as viewed from one side in the thickness direction of a semiconductor chip.

[0041] Figure 8 This is a cross-sectional view schematically showing a pickup step in a method for manufacturing a semiconductor device.

[0042] Figure 9 It is a cross-sectional view schematically showing the state after the die bonding step and the wire bonding step in the method of manufacturing a semiconductor device.

[0043] Figure 10 It is a cross-sectional view schematically showing a sealing step in a method of manufacturing a semiconductor device.

[0044] Description of Reference Numerals

[0045] 1: Cutting die bonding film,

[0046] 10: Chip bonding sheet,

[0047] 20: cutting belt,

[0048] 21: base material layer, 22: adhesive layer. DETAILED DESCRIPTION

[0049] Hereinafter, one embodiment of the dicing tape and the dicing die-bonding film including the dicing tape according to the present invention will be described with reference to the drawings.

[0050] The dicing die-bonding film 1 of this embodiment is as follows Figure 1 As shown, the die-bonding sheet 10 includes a dicing tape 20 and an adhesive layer 22 (described later) laminated on the dicing tape 20 and bonded to a semiconductor wafer.

[0051] It should be noted that the figures in the accompanying drawings are schematic diagrams, and the aspect ratios may not be the same as those of the actual objects.

[0052] The dicing die-bonding film 1 of this embodiment is cured by irradiating the adhesive layer 22 with active energy rays (e.g., ultraviolet rays) during use. Specifically, in a state where the die-bonding sheet 10, with a semiconductor wafer bonded to one side, and the adhesive layer 22 attached to the other side of the die-bonding sheet 10 are stacked, at least the adhesive layer 22 is irradiated with ultraviolet rays or the like. For example, ultraviolet rays or the like are irradiated from the side where the base layer 21 is disposed, and the ultraviolet rays or the like pass through the base layer 21 and reach the adhesive layer 22. The adhesive layer 22 is cured by the irradiation with ultraviolet rays or the like.

[0053] Since the adhesive layer 22 is cured after irradiation, the adhesive strength of the adhesive layer 22 can be reduced. Therefore, after irradiation, the die-bonding sheet 10 (with the semiconductor chip bonded thereto) can be relatively easily peeled off from the adhesive layer 22. The die-bonding sheet 10 is bonded to an adherend such as a circuit board or a semiconductor chip during the manufacture of a semiconductor device.

[0054] <Dicing Tape for Die-Bond Film>

[0055] The dicing tape 20 is usually a long sheet and is stored in a rolled state until used. The dicing die-bonding film 1 of this embodiment is attached to an annular frame having an inner diameter slightly larger than that of a silicon wafer to be cut and then cut for use.

[0056] The dicing tape 20 includes a base layer 21 and an adhesive layer 22 superposed on the base layer 21. The adhesive layer 22 of the dicing tape 20 is, for example, a pressure-sensitive adhesive layer.

[0057] [Base material layer of dicing tape]

[0058] In the present embodiment, the base material layer 21 superposed on the adhesive layer 22 has a laminated structure (for example, a two-layer structure or a three-layer structure).

[0059] like Figure 2A and Figure 2BAs shown in FIG, the substrate layer 21 includes at least a first substrate layer 21a containing an ethylene-acrylic acid copolymer resin and a second substrate layer 21b containing a resin other than the ethylene-acrylic acid copolymer resin. In addition, the second substrate layer 21b is arranged between the first substrate layer 21a and the adhesive layer 22.

[0060] For example, Figure 2A As shown, the substrate layer 21 is composed of two layers, a first substrate layer 21a and a second substrate layer 21b. The two-layer substrate layer 21 includes a first substrate layer 21a comprising an ethylene-acrylic acid copolymer resin (EAA), and a second substrate layer 21b comprising a resin other than the ethylene-acrylic acid copolymer resin, which is laminated on the first substrate layer 21a. For example, one surface of the second substrate layer 21b overlaps one surface of the adhesive layer 22.

[0061] The base material layer 21 having such a two-layer laminated structure is produced by, for example, co-extrusion molding of the respective layers and integration of the two layers.

[0062] In the two-layer substrate layer 21, the second substrate layer 21b preferably comprises ethylene-vinyl acetate copolymer (EVA). This allows the substrate layer 21 to utilize the high elasticity, characteristic of ethylene-acrylic acid copolymer (EAA), as well as the high thermal shrinkage at high temperatures characteristic of EVA. Consequently, after the dicing tape 20 is stretched during the expansion process, for example, the spacing (kerf) between adjacent semiconductor chips can be adequately maintained.

[0063] On the other hand, for example, Figure 2B As shown in FIG. 2 , the substrate layer 21 may be composed of three layers, namely, a first substrate layer 21a, a second substrate layer 21b, and a third substrate layer 21c. The three-layer substrate layer 21 preferably includes a first substrate layer 21a and a third substrate layer 21c, each of which includes an ethylene-acrylic acid copolymer resin (EAA), and a second substrate layer 21b disposed between these layers and including a resin other than the ethylene-acrylic acid copolymer resin.

[0064] The base material layer 21 having such a three-layer laminated structure is produced by, for example, co-extrusion molding of the respective layers and is formed by integrating the three layers.

[0065] In the substrate layer 21 of the three-layer structure, it is preferred that the first substrate layer 21a and the third substrate layer 21c respectively configured on both sides include ethylene-acrylic acid copolymer resin (EAA), and the second substrate layer 21b configured between the first substrate layer 21a and the third substrate layer 21c includes ethylene-vinyl acetate copolymer resin (EVA). Thus, the substrate layer 21 can exert the characteristics of ethylene-acrylic acid copolymer resin (EAA) such as higher elasticity, and the substrate layer 21 can also exert the characteristics of ethylene-vinyl acetate copolymer resin (EVA) such as higher thermal shrinkage at high temperature. Therefore, after the cutting tape 20 is stretched, for example, by an expansion process, the spacing distance (incision) between adjacent semiconductor chips can be fully maintained. It should be noted that in the substrate layer 21, for example, the layer farthest from the adhesive layer 22 is the first substrate layer 21a, and the layer overlapping with the adhesive layer 22 is the third substrate layer 21c. The second substrate layer 21b is configured between the first substrate layer 21a and the third substrate layer 21c.

[0066] In the two-layered base layer 21 , the ratio of the thickness of the second base layer 21 b to the thickness of the first base layer 21 a (thickness of the second base layer 21 b / thickness of the first base layer 21 a ) is preferably 1 or more and 10 or less.

[0067] In the three-layer structure of the substrate layer 21, the ratio of the thickness of the inner layer to the total thickness of the outer layer (the thickness of the second substrate layer 21b / the total thickness of the first substrate layer 21a and the third substrate layer 21c) is preferably 1 or more and 10 or less. Furthermore, the thicknesses of the first substrate layer 21a and the third substrate layer 21c can be substantially the same. For example, the ratio of the thickness of the first substrate layer 21a to the thickness of the third substrate layer 21c can be 0.9 or more and 1.1 or less.

[0068] The first base material layer 21a and the third base material layer 21c may have the same structure. In other words, the first base material layer 21a and the third base material layer 21c may have the same thickness and material.

[0069] The thickness (total thickness) of the base layer 21 is preferably 80 μm or more and 150 μm or less. This value is the average of measurements taken at at least three randomly selected locations. The thickness of the adhesive layer 22 is also the average value measured using the same procedure. By setting the thickness of the base layer 21 to 80 μm or more, stress can be applied more uniformly to the entire base layer 21, enabling better severing of the semiconductor wafer during the expansion process.

[0070] In the two-layer substrate layer 21, it is preferred that the first substrate layer 21a has a thickness of 5 μm to 40 μm, and the second substrate layer 21b has a thickness of 50 μm to 120 μm. This has the advantage of allowing the substrate layer 21 to more appropriately reflect the physical properties (characteristics) of each layer in the substrate layer 21.

[0071] In the three-layer substrate layer 21, it is preferred that the first substrate layer 21a and the third substrate layer 21c each independently have a thickness of 1 μm to 15 μm, and the second substrate layer 21b has a thickness of 70 μm to 120 μm. This has the advantage of allowing the substrate layer 21 to more appropriately reflect the physical properties (characteristics) of each layer in the substrate layer 21.

[0072] The base material layer 21 has a laminated structure (e.g., a three-layer structure) in which a plurality of layers are laminated. Therefore, a layer with a higher elastic modulus can be laminated with a layer with a lower elastic modulus. Therefore, the elastic modulus of the base material layer 21 can be controlled relatively easily. For example, when the elastic modulus of the base material layer 21 consisting of only one layer is high, the base material layer 21 is easily damaged during the expansion process. In addition, when the stress for cutting the semiconductor chip is transmitted from the force of the stretching cutting tape 20 via the base material layer 21 and the adhesive layer 22 during the expansion process, if the elastic modulus of the base material layer 21 consisting of only one layer is low, the above stress is slightly difficult to transmit.

[0073] Furthermore, since the base material layer 21 has a laminated structure, the thermal shrinkage rate of the base material layer 21 can be controlled relatively easily for the same reason as described above.

[0074] As described above, the base material layer 21 is composed of multiple layers, so that the physical properties (characteristics) of each layer can be exerted. Therefore, the base material layer composed of multiple layers is more likely to exert desired characteristics than a single-layer base material layer.

[0075] The base material layer 21 may include, for example, a metal foil, a rubber sheet, or a resin film.

[0076] As described above, the first substrate layer 21a contains at least ethylene-acrylic acid copolymer resin (EAA). The first substrate layer 21a is preferably composed of a film made of ethylene-acrylic acid copolymer resin. As a result, the dicing tape 20 can more fully have both high heat shrinkage and high elastic modulus.

[0077] Ethylene-acrylic acid copolymer resin (EAA) has at least ethylene structural units and acrylic acid structural units in the molecule. It should be noted that the structural units refer to the structures derived from the monomers (ethylene and acrylic acid) when polymerizing the ethylene-acrylic acid copolymer resin.

[0078] The ethylene-acrylic acid copolymer resin (EAA) may contain 5% by mass or more and 15% by mass or less of a structural unit of acrylic acid in the molecule.

[0079] The first base material layer 21a preferably contains 50% by mass or more of ethylene-acrylic acid copolymer resin, more preferably 60% by mass or more, and even more preferably 70% by mass or more. This allows the dicing tape 20 to have both high thermal shrinkage and high elastic modulus.

[0080] When the base material layer 21 has a three-layer structure, the third base material layer 21 c may be made of the same material as the first base material layer 21 a .

[0081] The second base material layer 21b preferably comprises at least one of ethylene-vinyl acetate copolymer resin, polypropylene resin, and low-density polyethylene (LDPE), more preferably comprises at least ethylene-vinyl acetate copolymer resin, and even more preferably is formed from a film made of ethylene-vinyl acetate copolymer resin. This allows the dicing tape 20 to more fully achieve both high thermal shrinkage and a high elastic modulus.

[0082] Ethylene-vinyl acetate copolymer resin (EVA) may contain 5% to 35% by mass of vinyl acetate structural units. It should be noted that the structural units refer to the structures derived from the monomers (ethylene and vinyl acetate) when polymerizing the ethylene-vinyl acetate copolymer.

[0083] The second substrate layer 21b preferably contains 10% by mass or more of an ethylene-vinyl acetate copolymer resin, more preferably 20% by mass or more, and even more preferably 30% by mass or more. This allows the dicing tape 20 to more effectively achieve both high thermal shrinkage and a high elastic modulus. The second substrate layer 21b can contain 90% by mass or less of an ethylene-vinyl acetate copolymer resin.

[0084] As needed, each layer of the substrate layer 21 may also include polyolefins such as low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), ethylene-propylene copolymers; ionomer resins; copolymers of ethylene such as ethylene-(meth)acrylate (random, alternating) copolymers; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT); polyacrylates; polyvinyl chloride (PVC); polyurethane; polycarbonate; polyphenylene sulfide (PPS); polyamides such as aliphatic polyamides and wholly aromatic polyamides (aromatic polyamides); polyetheretherketone (PEEK); polyimide; polyetherimide; polyvinylidene chloride; ABS (acrylonitrile-butadiene-styrene copolymer); cellulose or cellulose derivatives; silicone-containing polymers; fluorine-containing polymers, etc.

[0085] When each layer of the base material layer 21 comprises a resin film, the resin film may be subjected to a stretching treatment or the like, and deformability such as elongation may be controlled.

[0086] From the viewpoint of being able to apply active energy rays such as ultraviolet rays to the pressure-sensitive adhesive layer 22 from the back side, the base material layer 21 is preferably a light-transmitting (ultraviolet-transmitting) resin film or the like.

[0087] Each layer of the substrate layer 21 may further contain an antistatic agent. This antistatic agent prevents static electricity from being applied to the substrate layer 21. This effectively prevents electrostatic damage to the electronic circuits within the semiconductor chip caused by electrostatic discharge. Furthermore, by preventing static electricity, foreign matter such as dust is effectively prevented from adhering to the substrate layer 21.

[0088] The back side of the base layer 21 (the side not overlapped with the adhesive layer 22 ) may be subjected to a release treatment using a release agent (release agent) such as a silicone resin or a fluorine resin to impart releasability.

[0089] On the other hand, the surface of the base material layer 21 in contact with the adhesive layer 22 may be subjected to a surface treatment to improve adhesion with the adhesive layer 22. Examples of surface treatments include chemical or physical oxidation treatments such as chromic acid treatment, ozone exposure, flame exposure, high voltage electric shock exposure, and ionizing radiation treatment. Furthermore, a coating treatment using a coating agent such as an anchor coating agent, a primer, or an adhesive may be applied.

[0090] In this embodiment, the spectrum obtained by measuring the substrate layer 21 by differential scanning calorimetry preferably does not have an endothermic peak with a vertex at a temperature of 110°C or higher, more preferably does not have an endothermic peak with a vertex at a temperature of 105°C or higher, and further preferably does not have an endothermic peak with a vertex at a temperature of 100°C or higher. In other words, in this embodiment, the maximum endothermic peak appearing in the above spectrum preferably has a vertex at a temperature below 110°C, more preferably has a vertex at a temperature below 105°C, and further preferably has a vertex at a temperature below 100°C. For example, the above spectrum does not have an endothermic peak in the range of 110°C or higher and 200°C or lower. It should be noted that the above endothermic peak generally refers to the maximum peak with the highest height among the endothermic peaks.

[0091] For example, when the spectrum has an endothermic peak with a peak at a temperature lower than 100° C., a portion of the dicing tape 20 can be more fully shrunk by the heat treatment even if the temperature of the heat treatment after the dicing tape 20 is stretched is low.

[0092] For example, by making most of the resin contained in each layer constituting the base material layer 21 a resin having a melting point lower than 110° C., the spectrum does not have an endothermic peak having a peak at a temperature of 110° C. or higher.

[0093] Differential scanning calorimetry (DSC) was performed using a commercially available DSC apparatus. A sample weighing approximately 4 mg was measured and the temperature was raised from 0°C to 200°C at a rate of 10°C / minute under a nitrogen atmosphere. The sample was prepared by cutting the substrate layer 21 along its thickness. A standard measuring apparatus can be used.

[0094] In this embodiment, the absolute value of the difference between the melting point of the first substrate layer 21a and the melting point of the second substrate layer 21b is preferably 10°C or less. In the substrate layer 21 including the third substrate layer 21c, the absolute value of the maximum difference between the melting point of the first substrate layer 21a or the third substrate layer 21c and the melting point of the second substrate layer 21b is preferably 10°C or less.

[0095] It should be noted that the melting point of the first base layer 21 a or the third base layer 21 c is generally higher than the melting point of the second base layer 21 b .

[0096] The difference (absolute value) between the above melting points may be 5° C. or more.

[0097] The melting point of each of the first base material layer 21 a and the third base material layer 21 c is independently a predetermined value of, for example, 90° C. or higher and 130° C. or lower, preferably 90° C. or higher and lower than 100° C.

[0098] The melting point of the second base material layer 21 b is, for example, a predetermined value of 80° C. to 100° C., or preferably a predetermined value of 85° C. to 95° C.

[0099] The melting point is determined based on the results of the same measurement method as the differential scanning calorimetry described above. Specifically, differential scanning calorimetry is performed on the first substrate layer 21a, the second substrate layer 21b, or the third substrate layer 21c, and the temperature at the apex of the endothermic peak appearing in each spectrum is defined as the melting point. Typically, the apex of the largest peak among the endothermic peaks is used as the apex.

[0100] In this embodiment, the tensile storage modulus of the base material layer 21 at 90° C. is preferably 0.8 MPa or more, more preferably 1.0 MPa or more. This allows the spacing (kerf) between adjacent semiconductor chips to be more sufficiently maintained after the expansion step.

[0101] The tensile storage modulus of the base layer 21 at 90° C. may be 100 MPa or less, preferably 50 MPa or less, more preferably 10 MPa or less, and even more preferably 5 MPa or less. By reducing the tensile storage modulus, the dicing tape 20 can be thermally shrunk more effectively in the expansion step described below.

[0102] In this embodiment, the tensile storage modulus of the first base layer 21a at 90°C is preferably greater than the tensile storage modulus of the second base layer 21b at 90°C. In the base layer 21 including the third base layer 21c, the tensile storage modulus of both the first base layer 21a and the third base layer 21c at 90°C is preferably greater than the tensile storage modulus of the second base layer 21b at 90°C. This allows the spacing (kerf) between adjacent semiconductor chips to be more adequately maintained after the expansion process.

[0103] The first base layer 21a and the third base layer 21c may have a tensile storage modulus of, for example, 1.5 MPa to 5.0 MPa at 90°C. The second base layer 21b may have a tensile storage modulus of, for example, 0.5 MPa to less than 1.5 MPa at 90°C. The difference between the two values ​​may be 1.0 MPa to 2.0 MPa.

[0104] For example, the tensile storage modulus can be increased by increasing the content of a resin having a higher tensile storage modulus relative to the mass of each layer of the base layer 21 or relative to the total mass of the base layer 21. On the other hand, the elastic modulus can be reduced by decreasing the content of a resin having a higher tensile storage modulus.

[0105] The tensile storage modulus can be measured under the following measurement conditions.

[0106] Measuring device: solid viscoelasticity measuring device (e.g., measuring device name "RSAIII", manufactured by TA Instruments)

[0107] Sample size: initial length 40mm, width 10mm, thickness 20μm

[0108] (When the thickness is less than 20 μm, multiple sheets are stacked to form a laminate.)

[0109] Measurement environment: nitrogen atmosphere

[0110] Heating rate: 10℃ / min,

[0111] Measuring temperature: -40°C to 280°C

[0112] Read the tensile storage modulus at 90°C

[0113] Initial distance between chucks: 22.5mm

[0114] Frequency: 10Hz

[0115] Deformation: 0.005%

[0116] [Adhesive layer of dicing tape]

[0117] In the present embodiment, the adhesive layer 22 contains, for example, an acrylic copolymer, an isocyanate compound, and a polymerization initiator.

[0118] The adhesive layer 22 may have a thickness of 40 μm or less. The thickness of the adhesive layer 22 is preferably 10 μm or less, more preferably 7 μm or less, and even more preferably 5 μm or less. The adhesive layer 22 may have a thickness of 1 μm or greater. The shape and size of the adhesive layer 22 are generally the same as those of the substrate layer 21.

[0119] In the present embodiment, the adhesive layer 22 contains at least an acrylic copolymer having, in its molecule, as monomer units, a (meth)acrylate alkyl ester unit and a crosslinkable group-containing (meth)acrylate ester unit.

[0120] The term "unit" refers to a structure derived from each monomer after polymerization of monomers (eg, 2-ethylhexyl acrylate, hydroxyethyl acrylate, etc.) when polymerizing an acrylic copolymer. The same applies hereinafter.

[0121] In addition, in this specification, the expression "(meth)acrylate" means at least one of methacrylate and acrylate. The same applies to the term "(meth)acrylic type".

[0122] The acrylic copolymer comprises at least (meth)acrylate units and crosslinkable group-containing (meth)acrylate units as monomer units in its molecule. These monomer units constitute the main chain of the acrylic copolymer. In other words, these monomer units are derived from the monomers used to polymerize the acrylic copolymer. The side chains in the acrylic copolymer are contained in the monomer units that constitute the main chain.

[0123] The alkyl (meth)acrylate units are derived from alkyl (meth)acrylate monomers. In other words, the molecular structure after polymerization of the alkyl (meth)acrylate monomers is an alkyl (meth)acrylate unit. The term "alkyl" refers to a hydrocarbon moiety that is ester-bonded to (meth)acrylic acid.

[0124] The alkyl portion (hydrocarbon) in the (meth)acrylic acid alkyl ester unit may be a saturated hydrocarbon or an unsaturated hydrocarbon.

[0125] The alkyl portion (hydrocarbon) in the (meth)acrylate unit may be a linear hydrocarbon or a branched hydrocarbon, and may also contain a cyclic structure.

[0126] The number of carbon atoms of the alkyl portion (hydrocarbon) in the (meth)acrylate unit may be 6 or more and 22 or less.

[0127] In the acrylic copolymer, it is more preferable that the (meth)acrylic acid alkyl ester unit contains a saturated alkyl (meth)acrylic acid ester unit in which the alkyl portion is a saturated hydrocarbon having 6 to 22 carbon atoms.

[0128] Among all monomer units in the molecule of the acrylic copolymer, the proportion (on a molar basis) of alkyl (meth)acrylate units having an alkyl moiety with 6 or more carbon atoms is preferably the highest. For example, alkyl (meth)acrylate units having an alkyl moiety with 6 or more carbon atoms (preferably 8 or more) may account for 50% to 90% of all monomer units on a molar basis.

[0129] The saturated alkyl (meth)acrylate unit having 6 or more carbon atoms in the alkyl moiety preferably does not contain any benzene ring, ether bond (-CH2-O-CH2-), polar groups such as -OH groups and -COOH groups in the molecule. In the saturated alkyl (meth)acrylate unit having 6 or more carbon atoms in the alkyl moiety, the alkyl moiety may be a saturated straight-chain hydrocarbon or a saturated branched-chain hydrocarbon containing no atoms other than C and H and consisting of 6 or more and 10 or less carbon atoms.

[0130] The acrylic copolymer preferably includes, as the alkyl (meth)acrylate unit, a saturated branched alkyl (meth)acrylate unit having an alkyl moiety with 6 to 10 carbon atoms.

[0131] The structure of the alkyl portion (hydrocarbon portion) of the saturated branched alkyl (meth)acrylate unit may be any saturated branched alkyl structure, and may be an isoalkyl structure, a secondary (sec) alkyl structure, a neoalkyl structure, or a tertiary (tert) alkyl structure.

[0132] Specifically, examples of the saturated branched alkyl (meth)acrylate unit include units of isohexyl (meth)acrylate, isoheptyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Among these, the 2-ethylhexyl (meth)acrylate unit is preferred.

[0133] The structure of the alkyl portion (hydrocarbon portion) of the saturated linear alkyl (meth)acrylate unit may be any structure as long as it is a saturated linear alkyl structure.

[0134] Specifically, examples of the saturated linear alkyl (meth)acrylate unit include units of n-octyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, tridecyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, palmityl (meth)acrylate, stearyl (meth)acrylate, and behenyl (meth)acrylate.

[0135] The acrylic copolymer may contain one kind alone or two or more kinds of the alkyl (meth)acrylate units.

[0136] The crosslinkable group-containing (meth)acrylate units have hydroxyl groups capable of forming urethane bonds through a urethanization reaction, or polymerizable groups capable of polymerizing through a free radical reaction. More specifically, the crosslinkable group-containing (meth)acrylate units have at least one of an unreacted hydroxyl group or a free radical polymerizable carbon-carbon double bond as a polymerizable group. Preferably, a portion of the crosslinkable group-containing (meth)acrylate units have unreacted hydroxyl groups, while another portion (or all of the remaining portions) do not have hydroxyl groups and have free radical polymerizable carbon-carbon double bonds.

[0137] The acrylic copolymer includes, as a crosslinkable group-containing (meth)acrylate unit, a hydroxyl group-containing (meth)acrylate unit in which a hydroxyl group is bonded to a hydrocarbon portion having no more than 4 carbon atoms. When the adhesive layer 22 contains an isocyanate compound, the isocyanate group of the isocyanate compound can readily react with the hydroxyl group of the hydroxyl group-containing (meth)acrylate unit.

[0138] By pre-incorporating an acrylic copolymer containing hydroxyl (meth)acrylate units and an isocyanate compound into adhesive layer 22, adhesive layer 22 can be appropriately cured. Consequently, the acrylic copolymer can be fully gelled. As a result, adhesive layer 22 can maintain its shape while exhibiting adhesive properties.

[0139] The hydroxyl group-containing (meth)acrylate unit is preferably a hydroxyl group-containing C2-C4 alkyl (meth)acrylate unit in which an OH group is bonded to an alkyl group having 2 to 4 carbon atoms. The term "C2-C4 alkyl" refers to the number of carbon atoms in the hydrocarbon portion ester-bonded to (meth)acrylic acid. In other words, a hydroxyl group-containing C2-C4 alkyl (meth)acrylic acid monomer is a monomer formed by ester-bonding (meth)acrylic acid to an alcohol having 2 to 4 carbon atoms (typically a diol). The same shall apply throughout this specification.

[0140] The hydrocarbon portion of the C2-C4 alkyl group is typically a saturated hydrocarbon. For example, the hydrocarbon portion of the C2-C4 alkyl group is a linear saturated hydrocarbon or a branched saturated hydrocarbon. The hydrocarbon portion of the C2-C4 alkyl group preferably does not contain polar groups containing oxygen (O) or nitrogen (N).

[0141] Examples of the hydroxyl group-containing C2-C4 alkyl (meth)acrylate unit include units of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxyn-butyl (meth)acrylate, and hydroxybutyl (meth)acrylate such as hydroxyisobutyl (meth)acrylate. The hydroxyl group (—OH group) may be bonded to a terminal carbon (C) of the hydrocarbon moiety or to a carbon (C) other than the terminal carbon.

[0142] The acrylic copolymer includes, as the crosslinkable group-containing (meth)acrylate unit, a polymerizable (meth)acrylate unit having a radically polymerizable carbon-carbon double bond (polymerizable unsaturated double bond) in a side chain.

[0143] Specifically, the polymerizable (meth)acrylate unit has a molecular structure in which a hydroxyl group in the hydroxyl group-containing (meth)acrylate unit and an isocyanate group of an isocyanate group-containing (meth)acrylic monomer are urethane-bonded.

[0144] By making the above-mentioned acrylic copolymer contain a free radical polymerizable carbon-carbon double bond of a (meth)acrylate unit containing a crosslinking group, the adhesive layer 22 can be cured by irradiating active energy rays (ultraviolet rays, etc.) before the above-mentioned pickup process. For example, by irradiating active energy rays such as ultraviolet rays, free radicals are generated by a photopolymerization initiator, and with the help of the free radicals, the acrylic copolymers can undergo a cross-linking reaction with each other. As a result, the adhesive force of the adhesive layer 22 before irradiation can be reduced after irradiation. In addition, the chip bonding sheet 10 can be well peeled off from the adhesive layer 22.

[0145] Incidentally, as the active energy ray, ultraviolet rays, radiation or electron beams can be used.

[0146] The polymerizable (meth)acrylate units can be prepared by a urethanization reaction after the polymerization reaction for synthesizing the acrylic copolymer. For example, after copolymerizing an alkyl (meth)acrylate monomer with a hydroxyl group-containing (meth)acrylic monomer, the polymerizable (meth)acrylate units can be obtained by a urethanization reaction between the hydroxyl groups in some of the hydroxyl group-containing (meth)acrylate units and the isocyanate groups of an isocyanate group-containing polymerizable monomer.

[0147] The isocyanate group-containing (meth)acrylic monomer preferably has one isocyanate group and one (meth)acryloyl group in the molecule. Examples of such monomers include 2-methacryloyloxyethyl isocyanate.

[0148] In this embodiment, the acrylic copolymer may contain monomer units other than the above-mentioned monomer units. For example, it may contain units of (meth)acryloylmorpholine, N-vinyl-2-pyrrolidone, or acrylonitrile. By including (meth)acryloylmorpholine units as monomer units in the acrylic copolymer and varying the constituent ratio of the (meth)acryloylmorpholine units in the acrylic copolymer, the glass transition temperature or polarity of the acrylic copolymer can be relatively easily controlled.

[0149] In the acrylic copolymer contained in the adhesive layer 22, the above-mentioned units (constituent units) can be 1 H-NMR, 13 The molar ratio of the above units in the acrylic copolymer is usually calculated based on the amount (charge amount) of the acrylic copolymer when it is polymerized.

[0150] Preferably, the proportion of the (meth)acrylate units containing crosslinkable groups in the above-mentioned acrylic copolymer is 15 to 60 parts by mole of all monomer units (100 parts by mole), and 50 to 95% (on a molar basis) of the (meth)acrylate units containing crosslinkable groups form urethane bonds as described above. In other words, the above-mentioned acrylic copolymer preferably comprises 15 to 60 parts by mole of the (meth)acrylate units containing crosslinkable groups, based on 100 parts by mole of all monomer units, and 50 to 95% of the (meth)acrylate units containing crosslinkable groups are polymerizable (meth)acrylate units having free radical polymerizable carbon-carbon double bonds. This maintains the adhesive force between the die bonding sheet 10 and the adhesive layer 22 before curing, and improves the releasability between the die bonding sheet 10 and the adhesive layer 22 after curing.

[0151] The acrylic copolymer preferably contains 10 to 50 molar parts of polymerizable (meth)acrylate units based on 100 molar parts of all monomer units. This maintains the adhesive strength between the die-bonding sheet 10 and the adhesive layer 22 before curing, while also improving the releasability between the die-bonding sheet 10 and the adhesive layer 22 after curing.

[0152] In this embodiment, the adhesive layer 22 of the dicing tape 20 may further include an isocyanate compound having multiple isocyanate groups in its molecule. The presence of multiple isocyanate groups in the isocyanate compound allows for a cross-linking reaction between the acrylic copolymers in the adhesive layer 22. Specifically, one isocyanate group of the isocyanate compound reacts with a hydroxyl group of an acrylic copolymer, and another isocyanate group reacts with a hydroxyl group of another acrylic copolymer, thereby enabling a cross-linking reaction with the isocyanate compound.

[0153] In addition, the isocyanate compound may be a compound synthesized through a urethanization reaction or the like.

[0154] Examples of the isocyanate compound include diisocyanates such as aliphatic diisocyanates, alicyclic diisocyanates, and aromatic aliphatic diisocyanates.

[0155] Furthermore, examples of the isocyanate compound include polymeric polyisocyanates such as dimers and trimers of diisocyanate, and polymethylene polyphenylene polyisocyanates.

[0156] Examples of the isocyanate compound include polyisocyanates obtained by reacting an active hydrogen-containing compound with an excess of the above-mentioned isocyanate compound. Examples of the active hydrogen-containing compound include low-molecular-weight active hydrogen-containing compounds and high-molecular-weight active hydrogen-containing compounds.

[0157] In addition, as an isocyanate compound, allophanated polyisocyanate, biuret polyisocyanate, etc. can also be used.

[0158] The above-mentioned isocyanate compounds can be used alone or in combination of two or more.

[0159] The isocyanate compound is preferably a reaction product of an aromatic diisocyanate and a low-molecular-weight compound containing active hydrogen. The isocyanate group of the aromatic diisocyanate reactant reacts at a relatively slow rate, thereby suppressing overcuring of the adhesive layer 22 containing the reactant. The isocyanate compound preferably has three or more isocyanate groups in the molecule.

[0160] In this embodiment, the polymerization initiator contained in the adhesive layer 22 is a compound that can initiate a polymerization reaction by the energy of applied heat or light. By making the adhesive layer 22 contain a polymerization initiator, a cross-linking reaction between acrylic copolymers can be carried out when heat energy or light energy is applied to the adhesive layer 22. In detail, between acrylic copolymers having polymerizable (meth)acrylate units containing free radical polymerizable carbon-carbon double bonds, a polymerization reaction between polymerizable groups can be initiated, and the adhesive layer 22 can be cured. As a result, the adhesive force of the adhesive layer 22 can be reduced, and in the pickup process, the chip bonding sheet 10 can be easily peeled off from the cured adhesive layer 22.

[0161] As the polymerization initiator, for example, a photopolymerization initiator or a thermal polymerization initiator can be used. As the polymerization initiator, a general commercially available product can be used.

[0162] The adhesive layer 22 may further contain other components in addition to the above-mentioned components. Examples of such other components include thickeners, plasticizers, fillers, antioxidants, antioxidants, UV absorbers, light stabilizers, heat stabilizers, antistatic agents, surfactants, and light release agents. The types and amounts of such other components may be appropriately selected depending on the intended purpose.

[0163] <Die-bonding sheet of dicing die-bonding film>

[0164] like Figure 1 As shown, the die-bonding sheet 10 is overlapped with the adhesive layer 22 of the dicing tape 20 .

[0165] The thickness of the die-bonding sheet 10 is not particularly limited, and is, for example, 1 μm to 200 μm. The thickness may be 3 μm to 150 μm, or 5 μm to 140 μm. When the die-bonding sheet 10 is a laminate, the thickness is the total thickness of the laminate.

[0166] The die bond sheet 10 is, for example, Figure 1 As shown in FIG. 1 , a single-layer structure may be provided. In this specification, a single-layer structure refers to a structure having only a layer formed of the same composition. A structure in which a plurality of layers formed of the same composition are stacked is also a single-layer structure.

[0167] On the other hand, the die bond sheet 10 may have a multilayer structure, for example, in which two or more layers formed from different compositions are stacked. In the case where the die bond sheet 10 has a multilayer structure, it is sufficient as long as at least one layer constituting the die bond sheet 10 contains an acrylic polymer containing a crosslinkable group, as described later, and further contains a thermosetting resin as needed.

[0168] The elongation at break of the die-bonding sheet 10 at 0° C. is preferably less than 4.7%, more preferably less than 4.0%, and even more preferably less than 3.5%. This allows the die-bonding sheet to be more effectively cut. In other words, it is possible to exhibit better cutting properties.

[0169] It should be noted that the elongation at break may be 0.5% or more.

[0170] The elongation at break can be increased by, for example, reducing the content of a filler (described later) in the die-bonding sheet 10. On the other hand, the elongation at break can be reduced by increasing the content of the filler in the die-bonding sheet 10.

[0171] Details of the measurement conditions for the above-mentioned elongation at break are as follows.

[0172] Test piece cut from the die-bonding sheet: 40 mm in length and 10 mm in width

[0173] Measuring device: Dynamic viscoelasticity measuring device

[0174] (Product name: "RSA-G2" (manufactured by TA Instruments, etc.)

[0175] Measurement mode: Tensile mode

[0176] Initial distance between chucks: 20mm

[0177] Tensile speed: 1mm / sec

[0178] Measurement temperature: 0°C (measured after 4 minutes at 0°C)

[0179] When the test piece was fixed to the chuck, two silicone release-treated PET liners (50 μm thick) were used as cushioning materials in the chuck to prevent cracking of the test piece. The test piece was clamped by these PET liners.

[0180] When the distance between the chucks before the start of the tensile measurement is defined as L0 and the distance between the chucks at the time of fracture is defined as L1, the elongation at break is calculated using the following formula.

[0181] Elongation at break (%) = [(L1-L0) / L0] × 100

[0182] The die-bonding sheet 10 includes a crosslinkable group-containing acrylic polymer having crosslinkable groups in the molecule that undergo a crosslinking reaction by thermal curing. The crosslinkable group-containing acrylic polymer is a polymer compound obtained by polymerizing at least a (meth)acrylate monomer.

[0183] The crosslinkable group-containing acrylic polymer typically has the crosslinkable group in a side chain. The crosslinkable group-containing acrylic polymer may have the crosslinkable group at the end of the side chain. It should be noted that the crosslinkable group-containing acrylic polymer may have the crosslinkable group at at least one of the two ends of the main chain.

[0184] The crosslinkable group in the molecule of the crosslinkable group-containing acrylic polymer is not particularly limited as long as it is a functional group that undergoes a crosslinking reaction by a thermal curing treatment.

[0185] Examples of crosslinkable groups include hydroxyl groups and carboxyl groups. These crosslinkable groups can undergo a crosslinking reaction with epoxy groups or isocyanate groups. For example, a crosslinking reaction can occur between the crosslinkable group-containing acrylic polymer having at least one of hydroxyl groups and carboxyl groups in the molecule and a compound having an epoxy group or isocyanate group in the molecule (e.g., the epoxy resin described below).

[0186] In addition, examples of crosslinking groups include epoxy groups and isocyanate groups. These crosslinking groups can undergo a crosslinking reaction with hydroxyl groups or carboxyl groups. For example, a crosslinking reaction can occur between the above-mentioned crosslinking group-containing acrylic polymer having at least one of epoxy groups or isocyanate groups in the molecule and a compound having at least one of hydroxyl groups or carboxyl groups in the molecule (such as the phenolic resin described below).

[0187] In this embodiment, the crosslinkable group-containing acrylic polymer contained in the die-bonding sheet 10 preferably contains at least one of a hydroxyl group and a carboxyl group as a crosslinkable group. This allows the die-bonding sheet 10 to be more satisfactorily bonded to an adherend.

[0188] In the above-mentioned crosslinkable group-containing acrylic polymer, the proportion of the structural unit of the crosslinkable group-containing monomer can be greater than 0.1 mass% and less than 60.0 mass%, or greater than 0.5 mass% and less than 40.0 mass%, or greater than 1.0 mass% and less than 30.0 mass%, or greater than 3.0 mass% and less than 20.0 mass%.

[0189] The structural unit refers to a structure derived from each monomer after polymerization of monomers (eg, 2-ethylhexyl acrylate, hydroxyethyl acrylate, etc.) when polymerizing a crosslinkable group-containing acrylic polymer.

[0190] The crosslinkable group-containing acrylic polymer can be synthesized by, for example, a general polymerization method using a radical polymerization initiator.

[0191] The crosslinkable group-containing acrylic polymer preferably comprises, among the structural units in the molecule, a structural unit comprising an alkyl (meth)acrylate monomer in the largest proportion by mass. Examples of such alkyl (meth)acrylate monomers include C1-C18 alkyl (meth)acrylate monomers having an alkyl (hydrocarbon) group with 1 to 18 carbon atoms. Examples of such alkyl (meth)acrylate monomers include C1-C12 alkyl (meth)acrylate monomers having an alkyl (hydrocarbon) group with 1 to 12 carbon atoms.

[0192] Examples of the (meth)acrylic acid alkyl ester monomer include a (meth)acrylic acid saturated linear alkyl ester monomer and a (meth)acrylic acid saturated branched alkyl ester monomer.

[0193] Examples of the saturated linear alkyl (meth)acrylate monomer include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, tridecyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, palmityl (meth)acrylate, and stearyl (meth)acrylate. The linear alkyl moiety preferably has 2 to 8 carbon atoms.

[0194] Examples of saturated branched alkyl (meth)acrylate monomers include isoheptyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. The alkyl moiety may have an isoalkyl structure, a secondary alkyl structure, a neoalkyl structure, or a tertiary alkyl structure.

[0195] The crosslinkable group-containing acrylic polymer includes a structural unit derived from a crosslinkable group-containing monomer copolymerizable with an alkyl (meth)acrylate monomer.

[0196] In this embodiment, the crosslinkable group-containing acrylic polymer is an acrylic polymer obtained by copolymerizing at least an alkyl (meth)acrylate monomer and a crosslinkable group-containing monomer. In other words, the crosslinkable group-containing acrylic polymer has a structure in which structural units of the alkyl (meth)acrylate monomer and structural units of the crosslinkable group-containing monomer are linked in a random order.

[0197] Examples of the crosslinkable group-containing monomer include carboxyl group-containing (meth)acrylic monomers, acid anhydride (meth)acrylic monomers, hydroxyl group-containing (meth)acrylic monomers, epoxy group (glycidyl group)-containing (meth)acrylic monomers, isocyanate group-containing (meth)acrylic monomers, sulfonic acid group-containing (meth)acrylic monomers, phosphoric acid group-containing (meth)acrylic monomers, acrylamide, acrylonitrile and other functional group-containing monomers. It should be noted that the crosslinkable group-containing monomer may have an ether group or an ester group in the molecule.

[0198] The crosslinkable group-containing acrylic polymer is preferably a copolymer of at least one crosslinkable group-containing monomer selected from the group consisting of carboxyl group-containing (meth)acrylic monomers, hydroxyl group-containing (meth)acrylic monomers, epoxy group-containing (meth)acrylic monomers, and isocyanate group-containing (meth)acrylic monomers, and an alkyl (meth)acrylate (particularly an alkyl (meth)acrylate having an alkyl moiety with 8 or less carbon atoms).

[0199] Examples of carboxyl group-containing (meth)acrylic acid monomers include (meth)acrylic acid and mono(2-(meth)acryloyloxyethyl)succinate monomers. The carboxyl group may be located at the terminal portion of the monomer structure or may be bonded to a hydrocarbon other than the terminal portion.

[0200] Examples of hydroxyl-containing (meth)acrylic monomers include hydroxyethyl (meth)acrylate monomers, hydroxypropyl (meth)acrylate monomers, and hydroxybutyl (meth)acrylate monomers. The hydroxyl group may be located at the terminal portion of the monomer structure or may be bonded to a hydrocarbon other than the terminal portion.

[0201] Examples of epoxy-containing (meth)acrylic monomers include glycidyl (meth)acrylate monomers and 4-hydroxybutyl (meth)acrylate glycidyl ether. The epoxy group may be located at the terminal portion of the monomer structure or may be bonded to a hydrocarbon other than the terminal portion.

[0202] Examples of the isocyanate group-containing (meth)acrylic monomer include 2-methacryloyloxyethyl isocyanate, 1,1-(bisacryloyloxymethyl)ethyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-(2-methacryloyloxyethyloxy)ethyl isocyanate.

[0203] The die-bonding sheet 10 may include components other than the crosslinkable group-containing acrylic polymer. For example, the die-bonding sheet 10 may further include at least one of a thermosetting resin and a thermoplastic resin other than the crosslinkable group-containing acrylic polymer.

[0204] Examples of the thermosetting resin include epoxy resins, phenolic resins, amino resins, unsaturated polyester resins, polyurethane resins, silicone resins, and thermosetting polyimide resins. The thermosetting resins may be used alone or in combination of two or more.

[0205] Examples of the epoxy resins include bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolac type, o-cresol novolac type, trihydroxyphenylmethane type, tetraphenolethane type, hydantoin type, triglycidyl isocyanurate type, and glycidylamine type epoxy resins.

[0206] Phenolic resins can function as curing agents for epoxy resins. Examples of phenolic resins include novolac-type phenolic resins, resol-type phenolic resins, and polyoxystyrene such as poly(p-styrene oxide).

[0207] Examples of the novolac-type phenolic resin include phenol novolac resin, phenol aralkyl resin, cresol novolac resin, t-butylphenol novolac resin, and nonylphenol novolac resin.

[0208] The hydroxyl equivalent [g / eq] of the phenol resin may be, for example, 90 or more and 220 or less.

[0209] As the phenol resin, only one type may be used or two or more types may be used.

[0210] In this embodiment, the die-bonding sheet 10 may include the crosslinkable group-containing acrylic polymer and the thermosetting resin that undergo a crosslinking reaction with each other.

[0211] For example, the die-bonding sheet 10 may include an epoxy-containing acrylic polymer as the crosslinkable acrylic polymer and a phenolic resin as the thermosetting resin. Thus, the epoxy groups of the crosslinkable acrylic polymer and the hydroxyl groups of the phenolic resin can undergo a crosslinking reaction, thereby fully curing the die-bonding sheet 10.

[0212] As thermoplastic resins other than the above-mentioned acrylic polymers containing cross-linking groups that may be included in the chip bonding sheet 10, for example, natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylate copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resins such as 6-polyamide resin or 6,6-polyamide resin, phenoxy resin, acrylic resins that do not contain cross-linking functional groups in the molecule, saturated polyester resins such as PET or PBT, polyamideimide resins, fluororesins, etc.

[0213] As the above-mentioned thermoplastic resin, only one kind may be used or two or more kinds may be used.

[0214] In the die-bonding sheet 10 , the content of the crosslinkable group-containing acrylic polymer is preferably 8% by mass or more and 100% by mass or less.

[0215] In the die bonding sheet 10, the content ratio of the cross-linkable group-containing acrylic polymer in 100 parts by mass of the organic components other than the filler (e.g., the cross-linkable group-containing acrylic polymer, thermosetting resin, curing catalyst, silane coupling agent, dye) is preferably 15 parts by mass or more and 100 parts by mass or less, more preferably 40 parts by mass or more and 95 parts by mass or less, and even more preferably 60 parts by mass or more. It should be noted that by changing the content ratio of the thermosetting resin in the die bonding sheet 10, the elasticity or viscosity of the die bonding sheet 10 can be adjusted.

[0216] On the other hand, the content of the thermosetting resin in 100 parts by mass of the organic component may be 40 parts by mass or less.

[0217] The die-bonding sheet 10 may or may not contain fillers. By changing the amount of fillers in the die-bonding sheet 10, the elasticity and viscosity of the die-bonding sheet 10 can be more easily adjusted. Furthermore, the physical properties of the die-bonding sheet 10, such as electrical conductivity, thermal conductivity, and elastic modulus, can be adjusted.

[0218] Examples of the filler include inorganic fillers and organic fillers, and inorganic fillers are preferred.

[0219] Examples of inorganic fillers include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, boron nitride, and silicon dioxide such as crystalline silicon dioxide or amorphous silicon dioxide. Inorganic fillers may be made of simple metals or alloys such as aluminum, gold, silver, copper, and nickel. Examples of fillers include aluminum borate whiskers, amorphous carbon black, and graphite. The filler may be in various shapes, such as spherical, needle-like, or flaky. One or more of the aforementioned fillers may be used.

[0220] When the die-bonding sheet 10 contains a filler, the content of the filler may be 50% by mass or less of the total mass of the die-bonding sheet 10. The content of the filler may be, for example, 5% by mass or more.

[0221] The die-bonding sheet 10 may contain other components as necessary. Examples of the other components include a curing catalyst, a flame retardant, a silane coupling agent, an ion trapping agent, and a dye.

[0222] Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resins.

[0223] Examples of the silane coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane.

[0224] Examples of the ion-trapping agent include hydrotalcites, bismuth hydroxide, and benzotriazole.

[0225] As the other additives, only one type may be used or two or more types may be used.

[0226] From the viewpoint of facilitating adjustment of elasticity and viscosity, the die-bonding sheet 10 preferably contains the above-mentioned crosslinkable group-containing acrylic polymer, a thermosetting resin, and a filler.

[0227] The dicing die-bonding film 1 of this embodiment may include a release liner before use, covering one surface of the die-bonding sheet 10 (the surface of the die-bonding sheet 10 not overlapping the adhesive layer 22). The release liner is used to protect the die-bonding sheet 10 and is removed immediately before attaching an adherend (e.g., a semiconductor wafer) to the die-bonding sheet 10.

[0228] As the release liner, for example, a plastic film or paper surface-treated with a release agent such as a silicone-based release agent, a long-chain alkyl-based release agent, a fluorine-based release agent, or molybdenum sulfide can be used.

[0229] The release liner can be used as a supporting material for supporting the die-bonding sheet 10. The release liner is preferably used when overlapping the die-bonding sheet 10 on the adhesive layer 22. Specifically, the die-bonding sheet 10 is overlapped on the adhesive layer 22 in a state where the release liner and the die-bonding sheet 10 are stacked, and the release liner is peeled off (transferred) after overlapping, thereby enabling the die-bonding sheet 10 to be overlapped on the adhesive layer 22.

[0230] Next, a method for manufacturing the die-bonding sheet 10 and the dicing die-bonding film 1 according to the present embodiment will be described.

[0231] <Method for Manufacturing Dicing Die-Bond Film>

[0232] The method for manufacturing the dicing die-bonding film 1 according to the present embodiment includes:

[0233] The process of manufacturing the die bonding sheet 10;

[0234] The process of making the cutting tape 20; and

[0235] A step of overlapping the manufactured die-bonding sheet 10 and the dicing tape 20 .

[0236] [Process of Manufacturing Die Bonding Sheet]

[0237] The process of manufacturing the die bond sheet 10 includes:

[0238] a resin composition preparation step of preparing a resin composition for forming the die-bonding sheet 10 ; and

[0239] A die-bonding sheet forming step of forming the die-bonding sheet 10 from the resin composition.

[0240] In the resin composition preparation process, for example, the crosslinkable group-containing acrylic polymer is mixed with an epoxy resin, a phenolic resin, or a curing catalyst, and a solvent, and each resin is dissolved in the solvent to prepare the resin composition. The viscosity of the composition can be adjusted by varying the amount of solvent. It should be noted that commercially available products can be used as these resins.

[0241] In the die bond sheet forming process, for example, the resin composition prepared as described above is applied to a release liner. The coating method is not particularly limited, and general coating methods such as roll coating, screen coating, and gravure coating can be employed. The applied composition is then cured by desolvation treatment or curing treatment, as needed, to form the die bond sheet 10.

[0242] [Process of making cutting tape]

[0243] The process of making cutting tape has:

[0244] Synthesis process for synthesizing acrylic copolymers;

[0245] an adhesive layer forming step of volatilizing a solvent from an adhesive composition comprising the acrylic copolymer, the isocyanate compound, the polymerization initiator, the solvent, and other components appropriately added according to the purpose, thereby forming the adhesive layer 22;

[0246] a base material layer manufacturing step of manufacturing the base material layer 21; and

[0247] A lamination step is to laminate the base layer 21 and the adhesive layer 22 by laminating the adhesive layer 22 to the base layer 21 .

[0248] In the synthesis step, for example, a C6-C12 alkyl (meth)acrylate monomer having an alkyl moiety of 6 to 12 carbon atoms and a hydroxyl group-containing (meth)acrylic monomer are radically polymerized to synthesize an acrylic copolymer intermediate.

[0249] Free radical polymerization can be carried out using conventional methods. For example, the acrylic copolymer intermediate can be synthesized by dissolving the above-mentioned monomers in a solvent, stirring while heating, and adding a polymerization initiator. To adjust the molecular weight of the acrylic copolymer, polymerization can be carried out in the presence of a chain transfer agent.

[0250] Next, a urethanization reaction is performed to bond some of the hydroxyl groups in the hydroxyl-containing (meth)acrylate units contained in the acrylic copolymer intermediate to the isocyanate groups of the isocyanate-containing polymerizable monomer. As a result, some of the hydroxyl-containing (meth)acrylate units become polymerizable (meth)acrylate units containing free-radically polymerizable carbon-carbon double bonds.

[0251] The urethanization reaction can be carried out by a conventional method. For example, the acrylic copolymer intermediate and the isocyanate group-containing polymerizable monomer are stirred while heating in the presence of a solvent and a urethanization catalyst. This allows urethanization bonds to form between some of the hydroxyl groups in the acrylic copolymer intermediate and the isocyanate groups in the isocyanate group-containing polymerizable monomer.

[0252] In the adhesive layer production process, for example, an acrylic copolymer, an isocyanate compound, and a polymerization initiator are dissolved in a solvent to prepare an adhesive composition. By changing the amount of the solvent, the viscosity of the composition can be adjusted. Next, the adhesive composition is applied to a release liner. As a coating method, general coating methods such as roller coating, screen coating, and gravure coating can be adopted. By subjecting the applied composition to desolvation treatment or curing treatment, the applied adhesive composition is cured to produce the adhesive layer 22.

[0253] In the substrate layer production step, the substrate layer can be produced by film formation using a common method. Examples of film formation methods include calendering, casting in an organic solvent, inflation extrusion in a closed system, T-die extrusion, and dry lamination. Coextrusion can also be used. It should be noted that commercially available films can be used as the substrate layer 21 or as the layers constituting the substrate layer 21.

[0254] In the lamination step, the adhesive layer 22 in a state of being overlapped with the release liner is overlapped and laminated with the base layer 21. In addition, the release liner may be in a state of being overlapped with the adhesive layer 22 until before use.

[0255] To promote the reaction between the crosslinking agent and the acrylic copolymer and the surface of the base layer 21 , an aging treatment step may be performed at 50° C. for 48 hours after the lamination step.

[0256] Through these steps, the dicing tape 20 can be manufactured.

[0257] [Process of Overlaying the Die-Bond Sheet and Dicing Tape]

[0258] In the step of overlaying the die-bonding sheet 10 and the dicing tape 20 , the die-bonding sheet 10 is attached to the adhesive layer 22 of the dicing tape 20 manufactured as described above.

[0259] During this lamination, the release liner is peeled off from the adhesive layer 22 of the dicing tape 20 and the die-bonding sheet 10, respectively, and the die-bonding sheet 10 and the adhesive layer 22 are directly contacted and laminated together. For example, lamination can be performed by pressure bonding. The temperature during lamination is not particularly limited, and is, for example, 30°C or higher and 50°C or lower, preferably 35°C or higher and 45°C or lower. The linear pressure during lamination is not particularly limited, and is preferably 0.1kgf / cm or higher and 20kgf / cm or lower, and more preferably 1kgf / cm or higher and 10kgf / cm or lower.

[0260] The dicing die-bonding film 1 manufactured as described above through the above-mentioned steps is used as an auxiliary tool for manufacturing a semiconductor device (semiconductor integrated circuit), for example.

[0261] In the method for manufacturing a semiconductor device using the dicing die-bonding film 1 , for example, a semiconductor device having a semiconductor chip is manufactured using the dicing die-bonding film including the dicing tape and the die-bonding sheet superimposed on the dicing tape.

[0262] The method for manufacturing a semiconductor device comprises the following steps:

[0263] a mounting step of placing the die-bonding sheet between the adhesive layer of the dicing tape and the semiconductor wafer, thereby fixing the semiconductor wafer to the dicing tape via the die-bonding sheet; and

[0264] an expansion step of cutting the semiconductor wafer and the die-bonding sheet together by stretching the dicing tape, thereby cutting the semiconductor wafer into small pieces to obtain a semiconductor chip group;

[0265] A portion of the stretched dicing tape is heated around the semiconductor chip group to shrink it.

[0266] Hereinafter, the method for manufacturing a semiconductor device (the method for using the dicing die-bonding film) will be described in further detail.

[0267] <Method for Manufacturing a Semiconductor Device (Method for Using a Dicing Die-Bonding Film in Manufacturing a Semiconductor Device)>

[0268] In a method for manufacturing a semiconductor device, semiconductor chips are usually cut out from a semiconductor wafer having a circuit surface formed thereon and then assembled. In this case, the dicing die-bonding film of this embodiment is used as a manufacturing auxiliary tool.

[0269] In the semiconductor device manufacturing method of this embodiment, a semiconductor device having a semiconductor chip is manufactured using a dicing die-bonding film including a dicing tape having a base layer and an adhesive layer overlapping the base layer, and a die-bonding sheet overlapping the dicing tape.

[0270] The method for manufacturing a semiconductor device according to this embodiment includes the following steps:

[0271] A mounting step of attaching one side of a semiconductor wafer to the die-bonding sheet 10 of the dicing die-bonding film 1 and fixing the semiconductor wafer to the dicing tape 20 via the die-bonding sheet 10 ; and

[0272] In the expansion step, the dicing tape 20 is stretched to cut the semiconductor wafer and the die-bonding sheet 10 together using the fragile portion of the semiconductor wafer as a boundary.

[0273] Furthermore, the method for manufacturing a semiconductor device according to the present embodiment includes a pickup step of peeling the small-piece die-bonding sheet 10 attached to the adhesive layer 22 of the dicing tape 20 from the adhesive layer 22 together with the semiconductor chip.

[0274] In detail, the manufacturing method of the semiconductor device of this embodiment has the following steps, for example: a stealth cutting step, using a laser to form a fragile part inside the semiconductor wafer with a back grinding tape attached, and preparing to process the semiconductor wafer into a semiconductor chip (small piece) by cutting; a back grinding step, grinding the semiconductor wafer with a back grinding tape attached to reduce the thickness; the above-mentioned mounting step, attaching one side of the semiconductor wafer with a thinned thickness (for example, the side opposite to the circuit surface) to the chip bonding sheet 10, and fixing the semiconductor wafer to the cutting tape 20 with the help of the chip bonding sheet 10; the above-mentioned expansion step, cutting the semiconductor wafer by stretching the cutting tape 20 to make a semiconductor chip and expand the interval between adjacent semiconductor chips; and the above-mentioned picking step, peeling off the chip bonding sheet 10 and the adhesive layer 22, and taking out the semiconductor chip (small piece) in the state of being attached to the chip bonding sheet 10.

[0275] The manufacturing method of the semiconductor device of this embodiment also has the following steps: a chip bonding step, in which the chip bonding sheet 10 attached to the semiconductor chip is bonded to the adherend; a curing step, in which the chip bonding sheet 10 bonded to the adherend is cured; a wire bonding step, in which the electrodes of the electronic circuit in the semiconductor chip are electrically connected to the adherend using wires; and a sealing step, in which the semiconductor chip and wires on the adherend are sealed using a thermosetting resin.

[0276] The stealth cutting process is a process in the so-called SDBG (Stealth Dicing Before Grinding) process. Figures 3A to 3C As shown in FIG, a fragile portion for cutting the pattern wafer with the circuit surface formed thereon into semiconductor chips is formed inside the semiconductor wafer W. Specifically, first, a back grinding tape G is attached to the circuit surface of the semiconductor wafer W (see FIG. Figure 3A Then, with the back grinding tape G attached, grinding (preliminary back grinding) is performed using a grinding pad K until the semiconductor wafer W reaches a predetermined thickness (see Figure 3B ). Then, by irradiating the thinned semiconductor wafer W with laser light, a fragile portion is formed inside the semiconductor wafer W (see Figure 3C ).

[0277] A half-cut process may be performed instead of the stealth cut process. The half-cut process is a process in the so-called DBG (Dicing Before Grinding) process.

[0278] In the half-dicing process, in order to process the semiconductor wafer into semiconductor chips (dividing pieces) by dividing the semiconductor wafer, grooves are formed in the semiconductor wafer and then the semiconductor wafer is ground to reduce its thickness.

[0279] Specifically, the half-cutting process involves cutting a semiconductor wafer with a circuit surface into semiconductor chips (chips). More specifically, wafer processing tape is applied to the surface of the semiconductor wafer opposite the circuit surface. While the wafer processing tape is applied to the semiconductor wafer, a dividing groove is formed in the semiconductor wafer. Back grinding tape is applied to the grooved surface, and the initially applied wafer processing tape is removed.

[0280] The dicing die-bonding film of the present embodiment is preferably used in the SDBG (Stealth Dicing Before Grinding) process or the DBG (Dicing Before Grinding) process for dividing a semiconductor wafer to manufacture semiconductor chips as described above.

[0281] During the back grinding process, Figure 3D As shown, the semiconductor wafer W, with the back grinding tape G attached, is further ground to reduce its thickness to the thickness of the semiconductor chips (chips) to be produced by the severing process described later. For example, the semiconductor wafer W after the half-cutting process is ground to a predetermined thickness so that it does not separate into individual pieces. This grinding process allows the die bond sheet 10 to be severed simultaneously with the semiconductor wafer W being severed into semiconductor chips during the expansion process described later (particularly the low-temperature expansion process).

[0282] During the installation process, Figure 4A and Figure 4B As shown in FIG, the semiconductor wafer W is fixed to the dicing tape 20. Specifically, a dicing ring R is attached to the adhesive layer 22 of the dicing tape 20, and the semiconductor wafer W (see FIG) thinned by cutting as described above is attached to the exposed surface of the die bonding sheet 10. Figure 4A ). Next, the back grinding tape G is peeled off from the semiconductor wafer W (see Figure 4B ).

[0283] In the expansion process, Figures 5A to 5C As shown in FIG, the semiconductor wafer W is cut into small pieces by cutting the semiconductor wafer W, and the small pieces of semiconductor chips X are produced, and the intervals between the produced semiconductor chips X are expanded. Specifically, after the dicing ring R is attached to the adhesive layer 22 of the dicing tape 20, the holding tool H (see FIG. 2 ) fixed to the expansion device is Figure 5A The dicing die bonding film 1 is stretched in the surface direction by pushing up the lifting member U provided by the expansion device from the lower side of the dicing die bonding film 1 (see Figure 5B ). Thus, the semiconductor wafer W is cut under specific temperature conditions. The temperature conditions are, for example, -20 to 0°C, preferably -15 to 0°C, and more preferably -10 to -5°C. By lowering the lifting member U, the expanded state is released (see Figure 5C , so far it is the low temperature expansion process).

[0284] Furthermore, in the expansion process, Figure 6A-6B As shown, the dicing tape 20 is stretched under higher temperature conditions (e.g., 10°C to 25°C) to expand the area. This allows adjacent semiconductor chips X to be separated along the film surface after dicing, and further increases the kerf (the distance between adjacent semiconductor chips) (room temperature expansion step).

[0285] In the present embodiment, the dicing tape 20 is stretched in the surface direction by the expansion process. At this time, if the dicing tape 20 is not heated around the plurality of semiconductor chip groups that have been sliced, the portion (central portion) of the dicing tape 20 that overlaps with the plurality of semiconductor chips will shrink to its original shape. In this way, in order to suppress the shrinkage of the dicing tape 20, a heat treatment is applied to a portion of the dicing tape 20 that is along the periphery of the plurality of semiconductor chip groups that have been sliced. The heat treatment is applied, for example, in such a manner that the surface of the heated portion of the dicing tape 20 becomes approximately 90°C or higher and 120°C or lower. In a specific example, a heat treatment is applied to the portion of the dicing tape 20 that does not overlap with the plurality of semiconductor chips and that is along the periphery of the plurality of semiconductor chip groups. For example, as Figure 7 As shown, the heat treatment is performed using a heater S, etc., that can be moved circumferentially along the periphery of the plurality of semiconductor chip groups that have been diced. During the heat treatment, if the surface temperature of the heated portion of the dicing tape 20 is set to approximately 120°C or below, the temperature of the heated portion of the dicing tape 20 can be lower than 100°C. It should be noted that the temperature setting of the heater S itself, the rotation speed (movement speed) of the heater S, and the distance from the heater S to the dicing tape may affect the temperature of the dicing tape 20 during heating. Therefore, these settings should be adjusted appropriately according to production conditions, etc.

[0286] Before the pickup step, for example, the adhesive layer 22 superimposed on the base material layer 21 is irradiated with ultraviolet rays from the base material layer 21 side, thereby performing a curing treatment on the adhesive layer 22 (curing treatment step).

[0287] During the picking process, Figure 8 As shown, the semiconductor chip X, with the die-bonding sheet 10' attached, is peeled from the adhesive layer 22 of the dicing tape 20. Specifically, the needle member P is raised to lift the semiconductor chip X through the dicing tape 20. The lifted semiconductor chip X is held by the suction jig J.

[0288] In the die bonding process, the semiconductor chip X with the die bonding sheet 10' attached thereto is bonded to the adherend Z. In the die bonding process, for example, Figure 9 As shown, the semiconductor chips X in the state where the small pieces 10 ′ of the die-bonding sheet are attached are sometimes gradually stacked multiple times.

[0289] During the curing process, in order to enhance the reactivity of the crosslinking groups (e.g., epoxy groups) in the crosslinking group-containing acrylic polymer contained in the chip bonding sheet 10' and to cure the chip bonding sheet 10, a heat treatment is performed at a temperature of, for example, 100°C to 180°C.

[0290] In the wire bonding process, the semiconductor chip X (chip) and the adherend Z are connected by wires L while being heated (see, for example, Figure 9 ).

[0291] In the sealing process, Figure 10 As shown, the semiconductor chip X and the die-bonding sheet 10' are sealed with a thermosetting resin M such as epoxy resin. In the sealing step, a heat treatment is performed at a temperature of 100°C to 180°C, for example, to promote a curing reaction of the thermosetting resin M.

[0292] In the semiconductor industry in recent years, with the further development of integration technology, thinner semiconductor chips (for example, a thickness of more than 20 μm and less than 50 μm) and thinner chip bonding sheets (for example, a thickness of more than 1 μm and less than 40 μm, preferably less than 7 μm, and more preferably less than 5 μm) are desired.

[0293] In the above-mentioned method for manufacturing a semiconductor device (method for using a dicing chip bonding film), in the expansion process (especially the room temperature expansion process), the dicing tape 20 is stretched with a strong force along the surface direction so as to expand the area. In addition, after the dicing tape 20 is stretched, a portion of the dicing tape 20 is subjected to a heat treatment (for example, about 120°C) to shrink it. Specifically, the dicing tape 20 is shrunk by the heat treatment of the portion (peripheral portion) along the periphery of the plurality of semiconductor chips that does not overlap with the plurality of semiconductor chips that have been sliced. This heating treatment, for example, Figure 7 As shown, this is achieved by moving the heater S and the like along the periphery of the plurality of semiconductor chip groups that have been diced. Specifically, two heaters and the like are moved along the periphery of the plurality of semiconductor chip groups so as to each form a half-circle.

[0294] From the perspective of energy conservation, the temperature of the above-mentioned heat treatment is preferably low. Therefore, for example, the temperature of the heat treatment is sometimes set in such a way that the maximum temperature of the dicing tape itself is lower than 100°C. In this case, there may be a situation where a part of the dicing tape 20 may not be able to fully shrink by the heat treatment. In the portion along the periphery of the semiconductor chip group (peripheral portion), if the dicing tape 20 cannot fully shrink, it may not be possible to fully suppress the force of the dicing tape 20 shrinking in the direction opposite to the stretching direction. In this state, the dicing tape 20 in the portion overlapping with the plurality of semiconductor chip groups is likely to shrink, and there is a possibility that the spacing distance (incision) between adjacent semiconductor chips cannot be fully maintained.

[0295] In contrast, in the dicing die-bonding film 1 of this embodiment, the dicing tape 20 comprises a first base layer 21a comprising an ethylene-acrylic acid copolymer resin and a second base layer 21b comprising a resin other than the ethylene-acrylic acid copolymer resin (such as an ethylene-vinyl acetate copolymer resin). The second base layer 21b is disposed between the first base layer 21a and the adhesive layer 22 of the dicing tape 20. Therefore, the dicing tape 20 can sufficiently shrink even when heated at relatively low temperatures, and as described above, the forces causing shrinkage can be sufficiently suppressed. Therefore, after being stretched in the expansion process, the dicing tape 20 of this embodiment can shrink even when heated at relatively low temperatures, allowing the spacing (kerf) between adjacent semiconductor chips to be sufficiently maintained.

[0296] The dicing tape and the dicing die-bonding film of the present embodiment are as exemplified above, but the present invention is not limited to the dicing tape and the dicing die-bonding film exemplified above.

[0297] That is, various forms used in general dicing tapes and dicing die-bonding films can be adopted within a range that does not impair the effects of the present invention.

[0298] Matters disclosed in this specification include the following matters.

[0299] (1) A dicing tape comprising a base layer and an adhesive layer superposed on one side of the base layer,

[0300] The substrate layer has a plurality of stacked layers, and the plurality of layers include at least a first substrate layer containing an ethylene-acrylic acid copolymer resin and a second substrate layer containing a resin other than the ethylene-acrylic acid copolymer resin.

[0301] The second base layer is disposed between the first base layer and the adhesive layer.

[0302] According to the dicing tape having the above-described structure, the dicing tape can shrink even when heated at a relatively low temperature after being stretched, and thus the spacing distance (kerf) between adjacent semiconductor chips can be sufficiently maintained.

[0303] (2) The dicing tape according to (1) above, wherein the second base material layer contains at least ethylene-vinyl acetate copolymer resin.

[0304] (3) The dicing tape according to (1) or (2) above, wherein the base layer further comprises a third base layer comprising an ethylene-acrylic acid copolymer resin.

[0305] The second base layer is arranged between the first base layer and the third base layer.

[0306] (4) The dicing tape according to any one of (1) to (3) above, wherein the tensile storage modulus of the first base layer at 90°C is greater than the tensile storage modulus of the second base layer at 90°C.

[0307] (5) The dicing tape according to (3) or (4) above, wherein the tensile storage modulus of the first base layer and the third base layer at 90°C are both greater than the tensile storage modulus of the second base layer at 90°C.

[0308] (6) The dicing tape according to any one of (1) to (5) above, wherein the absolute value of the difference between the melting point of the first base material layer and the melting point of the second base material layer is 10° C. or less.

[0309] (7) The dicing tape according to any one of (1) to (6) above, wherein the maximum absolute value of the difference between the melting point of the first base layer or the third base layer and the melting point of the second base layer is 10° C. or less.

[0310] (8) The dicing tape according to any one of (1) to (7) above, wherein a spectrum obtained by measuring the base material layer by differential scanning calorimetry does not have an endothermic peak having a peak at a temperature of 100° C. or higher.

[0311] (9) The dicing tape according to any one of (1) to (8) above, wherein the base material layer has a tensile storage modulus at 90° C. of 1.0 MPa or more.

[0312] (10) The dicing tape according to any one of (1) to (9) above, which is used for manufacturing a semiconductor device.

[0313] (11) A dicing die-bonding film comprising the dicing tape according to any one of (1) to (10) above, and a die-bonding sheet superimposed on the dicing tape.

[0314] According to the dicing die-bonding film having the above-described structure, the dicing tape can shrink even when heated at a relatively low temperature after being stretched, and a sufficient spacing distance (kerf) between adjacent semiconductor chips can be maintained.

[0315] (12) A method for manufacturing a semiconductor device, wherein a semiconductor device having a semiconductor chip is manufactured using a dicing die-bonding film, the dicing die-bonding film comprising the dicing tape according to any one of (1) to (10) above, and a die-bonding sheet superimposed on the dicing tape.

[0316] The method for manufacturing a semiconductor device comprises the following steps:

[0317] a mounting step of placing the die-bonding sheet between the adhesive layer of the dicing tape and the semiconductor wafer, thereby fixing the semiconductor wafer to the dicing tape via the die-bonding sheet; and

[0318] an expansion step of cutting the semiconductor wafer and the die-bonding sheet together by stretching the dicing tape, thereby cutting the semiconductor wafer into small pieces to obtain a semiconductor chip group;

[0319] A portion of the stretched dicing tape is heated around the semiconductor chip group to shrink it.

[0320] According to the method for manufacturing a semiconductor device having the above-described structure, after the dicing tape is stretched in the expanding step, the spacing distance (kerf) between adjacent semiconductor chips can be sufficiently maintained.

[0321] Example

[0322] Next, the present invention will be described in more detail with reference to experimental examples, but the present invention is not limited to these.

[0323] The dicing tape was manufactured as follows: The dicing tape was bonded to the die-bonding sheet to manufacture a dicing die-bonding film.

[0324] <Production of Cutting Tape>

[0325] [Base material layer]

[0326] Using the resins (commercially available) shown below, three or two laminated base material layers (A to J) were prepared.

[0327] (Resin film for forming base material layer)

[0328] EAA-containing layer 1: melting point 95°C, tensile modulus (90°C) 2.62 [MPa]

[0329] Main component: Ethylene-acrylic acid copolymer resin (EAA)1

[0330] Other ingredients: polymer antistatic agent

[0331] EAA-containing layer 2: melting point 102°C, tensile modulus (90°C) 4.23 [MPa]

[0332] Main component: Ethylene-acrylic acid copolymer resin (EAA)2

[0333] Other ingredients: polymer antistatic agent

[0334] EVA containing layer 1: melting point 88°C, tensile modulus (90°C) 1.01 [MPa]

[0335] Ethylene vinyl acetate copolymer (EVA)1

[0336] EVA containing layer 2: melting point 94°C, tensile modulus (90°C) 1.05 [MPa]

[0337] Ethylene vinyl acetate copolymer (EVA)2

[0338] EVA containing layer 3: melting point 94°C, tensile modulus (90°C) 1.31 [MPa]

[0339] Main component: Ethylene vinyl acetate copolymer (EVA)2

[0340] Other ingredients: polymer antistatic agent

[0341] PP containing layer 1: melting point 124°C, tensile modulus (90°C) 24.7 [MPa]

[0342] Main ingredient: Polypropylene resin 1

[0343] Other ingredients: polymer antistatic agent

[0344] PP containing layer 2: melting point 92°C, tensile modulus (90°C) 1.92 [MPa]

[0345] Main ingredient: Polypropylene resin 1

[0346] Other ingredients: Ethylene vinyl acetate copolymer (EVA)1

[0347] (Formation of Base Material Layer)

[0348] The substrate layer is formed using an extrusion T-die molding machine. The extrusion temperature is 190°C. When producing a two-layer or three-layer laminate, the layers are integrated by coextrusion through a T-die. After the integrated substrate layer (laminate) is fully cured, it is wound into a roll and stored.

[0349] Table 1 shows the details of the structure of the base material layer.

[0350] [Table 1]

[0351]

[0352] [Adhesive layer]

[0353] Adhesive layers a, b, and c were prepared as follows.

[0354] [Adhesive layer a]

[0355] (Raw monomer for acrylic copolymer)

[0356] 2-Hydroxyethyl acrylate (HEA): 20 parts by mass

[0357] 2-Ethylhexyl acrylate (2EHA): 100 parts by mass

[0358] The above raw materials were added to a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer, and a stirring device. 0.2 parts by mass of azobisisobutyronitrile (AIBN) was used as a thermal polymerization initiator for 100 parts by mass of the total monomers. Toluene was added as a reaction solvent to achieve a total monomer concentration of 60% by mass. A polymerization reaction was carried out at 62°C for 6 hours and then at 75°C for 2 hours in a nitrogen stream to obtain an intermediate of an acrylic copolymer.

[0359] Next, 2-methacryloyloxyethyl isocyanate (hereinafter referred to as MOI) (product name "Karenz MOI", manufactured by Showa Denko Materials Co., Ltd.) was added to the liquid containing the intermediate of the obtained acrylic copolymer so as to provide 80 mol% relative to the total amount of HEA on a molar basis. Furthermore, 0.03% by mass of dibutyltin dilaurate was added as a reaction catalyst relative to MOI. Subsequently, an addition reaction treatment (urethanization reaction) was carried out at 50°C in an air flow for 12 hours to obtain an acrylic copolymer.

[0360] Next, 2.5 parts by mass of a photopolymerization initiator (product name "Omnirad 127," manufactured by IGM), 0.8 parts by mass of a polyisocyanate compound (product name "TAKENATE D-101A"), and 0.01 parts by mass of an antioxidant (product name "Irganox 1010," manufactured by BASF Japan) were added to 100 parts by mass of the acrylic copolymer to prepare an adhesive solution. This adhesive solution was applied to the treated surface of a silicone-treated PET release liner. Heat drying was performed at 120°C for 2 minutes to form a 5 μm thick adhesive layer.

[0361] [Adhesive layer b]

[0362] (Raw monomer for acrylic copolymer)

[0363] Acryloylmorpholine (ACMO): 8 parts by mass

[0364] 2-Hydroxyethyl acrylate (HEA): 20 parts by mass

[0365] 2-Ethylhexyl acrylate (2EHA): 72 parts by mass

[0366] The above raw materials were added to the same reaction vessel as above. Azobisisobutyronitrile (AIBN) was used as a thermal polymerization initiator at 0.2 parts by mass relative to 100 parts by mass of the total monomers. Ethyl acetate was added as the reaction solvent to achieve a total monomer concentration of 35% by mass. A polymerization reaction was carried out at 62°C for 5 hours and then at 75°C for 2 hours in a nitrogen stream to obtain an intermediate of an acrylic copolymer.

[0367] Next, the MOI was added to a liquid containing the intermediate of the obtained acrylic copolymer to provide 80 mol% of the total amount of HEA on a molar basis. Furthermore, 0.03% by mass of dibutyltin dilaurate was added as a reaction catalyst relative to the MOI. An addition reaction (urethanization reaction) was then carried out in an air stream at 50°C for 12 hours to obtain an acrylic copolymer.

[0368] Next, 2.5 parts by mass of a photopolymerization initiator (product name "Omnirad 127"), 1.00 parts by mass of a polyisocyanate compound (product name "TAKENATE D-101A"), and 0.01 parts by mass of an antioxidant (product name "Irganox 1010", manufactured by BASF Japan) were added to 100 parts by mass of the acrylic copolymer to prepare an adhesive solution. This adhesive solution was applied to the treated surface of a silicone-treated PET release liner. Heat drying was performed at 120°C for 2 minutes to form a 5 μm thick adhesive layer.

[0369] [Adhesive layer c]

[0370] To the liquid containing the acrylic copolymer obtained in the adhesive layer a, 2.5 parts by mass of a photopolymerization initiator (product name "Omnirad 127"), 0.5 parts by mass of a polyisocyanate compound (product name "TAKENATE D-101A"), and 0.01 parts by mass of an antioxidant ("Irganox 1010", manufactured by BASF Japan) were added relative to 100 parts by mass of the acrylic copolymer to prepare an adhesive solution. This adhesive solution was applied to the treated surface of a silicone-treated PET release liner. Heat drying was performed at 120°C for 2 minutes to form an adhesive layer with a thickness of 5 μm.

[0371] [Lamination of Adhesive Layer and Substrate Layer]

[0372] Next, the adhesive layer prepared as described above was bonded to the base material layer within 1 hour after the adhesive layer was prepared, and the adhesive layer was stored at 50° C. for 24 hours to produce a dicing tape.

[0373] Note that the first substrate layer shown in Table 2 is positioned farthest from the adhesive layer, and the second substrate layer is positioned closer to the adhesive layer than the first substrate layer. When the substrate layer has a three-layer structure, the third substrate layer overlaps one surface of the adhesive layer.

[0374] <Production of Die Bonding Sheet>

[0375] Die-bonding sheets α, β, and γ were produced as follows.

[0376] [Die Bonding Sheet α]

[0377] 35 parts by mass (solid content) of acrylic polymer (product name "SG-P3", manufactured by Nagase ChemteX Co., Ltd., glass transition temperature: 12°C, containing epoxy groups),

[0378] Epoxy resin (product name "JER1001", manufactured by Mitsubishi Chemical Corporation) 45 parts by mass,

[0379] 50 parts by mass of phenolic resin (product name "MEHC-7851SS", manufactured by Meiwa Chemicals Co., Ltd.),

[0380] Silica filler (product name "SO-25R", manufactured by ADMATECHS) 100 parts by mass,

[0381] Curing catalyst (product name "CUREZOL 2PHZ", manufactured by Shikoku Chemical Industry Co., Ltd.) 0.5 parts by mass

[0382] The above-mentioned raw materials were added to a predetermined amount of methyl ethyl ketone and mixed to prepare an adhesive composition solution having a total solid content concentration of 20% by mass.

[0383] Next, using an applicator, the adhesive composition was applied to the silicone release-treated surface of a PET release liner to form a coating film. This coating film was then heat-dried at 130°C for 2 minutes to produce a 10 μm thick die-bonding sheet on the PET release liner.

[0384] [Die Bonding Sheet β]

[0385] 35 parts by mass (solid content) of acrylic polymer (product name "SG-P3", manufactured by Nagase ChemteX Co., Ltd., glass transition temperature: 12°C, containing epoxy groups),

[0386] 30 parts by mass (solid content) of acrylic polymer (acrylic resin solution obtained by dissolving a copolymer of ethyl acrylate, butyl methacrylate, and glycidyl methacrylate in methyl ethyl ketone: weight average molecular weight Mw = 70,000 / epoxy equivalent = 444 (g / eq) / glass transition temperature Tg = 11°C),

[0387] 6 parts by mass of phenolic resin (product name "MEHC-7851SS", manufactured by Meiwa Chemicals Co., Ltd.),

[0388] Silica filler (product name "SE2050-MCV", manufactured by ADMATECHS) 27 parts by mass,

[0389] Silane coupling agent (product name "KBM-403", manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass

[0390] The above-mentioned raw materials were added to a predetermined amount of methyl ethyl ketone and mixed to prepare an adhesive composition solution having a total solid content concentration of 15% by mass.

[0391] Next, using the prepared adhesive composition, a die-bonding sheet having a thickness of 10 μm was produced on a PET release liner in the same manner as above.

[0392] [Die Bonding Sheet γ]

[0393] 100 parts by mass (solid content) of acrylic polymer (product name "PARACRON KG-8001", manufactured by Negami Industries, Ltd., containing epoxy groups),

[0394] 3 parts by mass of phenolic resin (product name "MEHC-7851SS", manufactured by Meiwa Chemicals Co., Ltd.),

[0395] Silica filler (product name "SE2050-MCV", manufactured by ADMATECHS) 10 parts by mass

[0396] The above-mentioned raw materials were added to a predetermined amount of methyl ethyl ketone and mixed to prepare an adhesive composition solution having a total solid content concentration of 12% by mass.

[0397] Next, using the prepared adhesive composition, a die-bonding sheet having a thickness of 10 μm was produced on a PET release liner in the same manner as above.

[0398] (Examples 1 to 9, Comparative Examples 1 to 5)

[0399] [Manufacturing of Dicing Die-Bond Film]

[0400] The configuration of each dicing die-bonding film is shown in Table 2. A dicing die-bonding film was produced by laminating a circular die-bonding sheet and a dicing tape at room temperature using a laminator.

[0401] [Table 2]

[0402]

[0403] <Measurement of Physical Properties of Dicing Die-Bond Film>

[0404] The physical properties of each layer constituting the dicing die-bonding film of each Example and each Comparative Example were measured as follows.

[0405] [Differential Scanning Calorimetry (DSC) Measurement of Substrate Layer]

[0406] The details of the differential scanning calorimetry method for measuring the substrate layer of the dicing tape are as described above. Table 2 shows the temperature at the top of the maximum endothermic peak that appeared in the measurement spectrum.

[0407] [Differential Scanning Calorimetry (DSC) Measurement of Each Layer Constituting the Base Material Layer]

[0408] The details of the DSC measurement method for the first substrate layer and the second substrate layer are as described above. Table 2 shows the melting points of the respective layers determined from the measurement results.

[0409] [Tensile storage modulus of the substrate layer of the dicing tape at 90°C]

[0410] The details of the method for measuring the tensile storage modulus of the substrate layer are as described above. Table 2 shows the measurement results of each elastic modulus at 90°C.

[0411] [Tensile storage modulus of each layer constituting the base material layer at 90°C]

[0412] The details of the method for measuring the tensile storage modulus of the dicing tape are as described above. Table 2 shows the measurement results of each elastic modulus at 90°C.

[0413] [Elongation at break of die-bonding sheet at 0°C]

[0414] The details of the method for measuring the elastic modulus of the die-bonding sheet at 0° C. are as described above. The measurement results are shown in Table 2.

[0415] Furthermore, the performance of the dicing die-bonding film produced as described above was evaluated as follows.

[0416] <Performance Evaluation (Interval Between Adjacent Semiconductor Chips in the Center (Kerf Width))>

[0417] (Preparation of evaluation samples)

[0418] As a sample for evaluation, a dicing die-bonding film with chips (dices) produced using a bare wafer was prepared.

[0419] Specifically, a bare wafer held by wafer processing tape (product name "UB-3083D," manufactured by Nitto Denko Corporation) was bonded to the die-bonding sheet of a dicing die-bonding film using a laminator. The wafer processing tape was then peeled from the wafer. The bonding conditions were: a bonding speed of 10 mm / s, a temperature of 50-80°C, and a pressure of 0.15 MPa.

[0420] (Wafer Preparation)

[0421] First, a wafer processing tape (product name "UB-3083D", manufactured by Nitto Denko Corporation) is attached to the first surface of a bare wafer (12 inches in diameter, 780 μm thick, manufactured by Tokyo Chemical Industry Co., Ltd.) where the modified area is to be formed. Next, a stealth cutting device (product name "DAL7360 (SDE05)", power: 0.25W, frequency: 80kHz, manufactured by DISCO Corporation) is used to form a modified area inside the bare wafer. In detail, a laser is irradiated from the back side (second side) opposite to the first side, and the laser focuses the light on the side of the wafer that is close to the first side. Irradiation is performed along the predetermined line for dividing the bare wafer. Thus, by ablation based on multiphoton absorption, a modified area for dicing is formed inside the wafer (at a depth of 50 μm from the first side of the wafer) by drawing a grid with a segment of 3 mm × 7 mm. Afterwards, a backside grinding device (product name "DGP8760", manufactured by DISCO) was used to grind the second side of the wafer, thereby thinning the wafer to a thickness of 30 μm. This process resulted in a wafer held by a wafer processing tape. This wafer contained sections for dicing the wafer into multiple chips (3 mm × 7 mm).

[0422] (Chip (chip) production)

[0423] The bare wafer produced by the above operation is attached to the dicing die bonding film. The bare wafer in the state of being attached to the dicing die bonding film is cut into small pieces by the expansion process. It should be noted that, in a state where the above-mentioned wafer processing tape is peeled off from the bare wafer, a small piece separation device (product name "Dieseparator DDS2300, manufactured by DISCO Corporation) is used to implement the expansion process. In addition, after cold expansion is implemented in the expansion process, room temperature expansion is implemented.

[0424] Cold expansion is carried out as follows. Specifically, a 12-inch diameter SUS ring frame (manufactured by DISCO) is pasted at room temperature in a predetermined area of ​​the frame to be pasted on the adhesive layer of the dicing die bonding film pasted on the bare wafer. Next, the bare wafer with the SUS ring frame pasted thereon is mounted on a small piece separation device. Furthermore, a cold expander unit is used to cut the wafer and the die bonding sheet under the conditions of an expansion temperature of -15°C, an expansion speed of 100 mm / s, and an expansion amount of 10 mm to obtain a plurality of chips with die bonding sheet layers.

[0425] Furthermore, room temperature expansion was performed under the conditions of an expansion speed of 1 mm / sec and an expansion amount of 10 mm in a room temperature environment.

[0426] Furthermore, while maintaining the expanded state, the dicing tape surrounding the outer edge of the wafer is thermally shrunk by a heater under the conditions of a heating temperature of 250°C, a heating distance of 20 mm, and a rotation speed of 3° / sec. Figure 7 The heat treatment method described above heats the portion of the dicing tape that does not overlap with the plurality of semiconductor chips, causing the heated portion to shrink. It should be noted that by performing the heat treatment under the above conditions, the temperature of the heated portion of the dicing tape itself can be lower than 100°C.

[0427] After heat shrinkage, the gaps (notches) between the chips on the die-bonding sheet were measured at multiple locations under a microscope. The notches were calculated by measuring the gaps at 10 random locations in the center and taking the arithmetic average of the measured values. A notch (average value) of 20 μm or greater was evaluated as "good (○)", a notch of 10 μm or greater but less than 20 μm was evaluated as "slightly good (△)", and a notch of less than 10 μm was evaluated as "poor (×)".

[0428] <Performance Evaluation (Division Properties of Die-Bond Sheet)>

[0429] (Preparation of evaluation samples)

[0430] As an evaluation sample, a dicing die bond film with chips (chips) made using a bare wafer was prepared. Specifically, a bare wafer held by a wafer processing tape (product name "UB-3083D", manufactured by Nitto Denko Corporation) was bonded to the die bond sheet of the dicing die bond film using a laminator. Next, the wafer processing tape was peeled off from the wafer. The bonding conditions were set as follows: a bonding speed of 10 mm / s, a temperature of 50-80°C, and a pressure of 0.15 MPa.

[0431] (Wafer Preparation)

[0432] First, a wafer processing tape (product name "UB-3083D", manufactured by Nitto Denko Corporation) is attached to the first surface of a bare wafer (12 inches in diameter, 780 μm thick, manufactured by Tokyo Chemical Industry Co., Ltd.) where the modified area is to be formed. Next, a stealth cutting device (product name "DAL7360 (SDE05)", power: 0.25W, frequency: 80kHz, manufactured by DISCO Corporation) is used to form a modified area inside the bare wafer. In detail, a laser is irradiated from the back side (second side) opposite to the first side, and the laser focuses the light on the side of the wafer that is close to the first side. Irradiation is performed along the predetermined line for dividing the bare wafer. Thus, by ablation based on multiphoton absorption, a modified area for dicing is formed inside the wafer (at a depth of 50 μm from the first side of the wafer) by drawing a grid with a segment of 3 mm × 7 mm. Afterwards, a backside grinding device (product name "DGP8760", manufactured by DISCO) was used to grind the second side of the wafer, thereby thinning the wafer to a thickness of 30μm. This process was continued until the wafer was held in this state by the wafer processing tape. This wafer contained sections for dicing the wafer into multiple chips (3mm×7mm).

[0433] (Chip (chip) production)

[0434] The bare wafer produced by the above operation is pasted on the dicing die bonding film. The bare wafer in the state of being pasted on the dicing die bonding film is cut into small pieces by the expansion process. It should be noted that the expansion process is carried out using a small piece separation device (product name "Dieseparator DDS2300, manufactured by DISCO") in a state where the above-mentioned wafer processing tape is peeled off from the bare wafer. In addition, after cold expansion is carried out in the expansion process, room temperature expansion is carried out. The cold expansion is carried out as follows. Specifically, on the adhesive layer of the dicing die bonding film pasted on the bare wafer, a SUS ring frame (manufactured by DISCO) with a diameter of 12 inches is pasted at room temperature in the predetermined area where the frame is to be pasted. Then, the bare wafer with the SUS ring frame pasted is mounted on the small piece separation device. In addition, using a cold expander unit, under the conditions of an expansion temperature of 0°C, an expansion speed of 100 mm / s, and an expansion amount of 12 mm, the wafer and the die bonding sheet are cut to obtain a plurality of chips with die bonding sheet layers. Furthermore, under the conditions of room temperature, expansion speed of 1mm / sec and expansion distance of 10mm, normal temperature expansion was carried out. And while maintaining the expansion state, the dicing tape surrounding the outer edge of the wafer was thermally shrunk by a heater under the conditions of heating temperature of 250℃, heating distance of 20mm and rotation speed of 3° / sec. Figure 7In this heat treatment method, the portion of the dicing tape that does not overlap with the plurality of semiconductor chips is heated, causing the heated portion to shrink. After shrinkage, light is irradiated from the back side of the tape to inspect the entire tape to ensure that the chips and die-bonding sheet have been severed. A microscope is used for more detailed verification.

[0435] (Division of Die Bonding Sheet)

[0436] The number of die-bonding sheets that could be severed along with the chips was determined among the total number of chips to be severed, and the severance rate was calculated. A severance rate of 99% or higher was rated "good (◯)," 85% or higher but less than 99% was rated "somewhat good (△)," and less than 85% was rated "poor (×).

[0437] As can be understood from the above evaluation results, the dicing die-bonding film of the example can shrink even when heated at a relatively low temperature after being stretched in the expansion process, compared to the dicing die-bonding film of the comparative example, and can sufficiently maintain the spacing (kerf) between adjacent semiconductor chips. Furthermore, the dicing die-bonding film of the example has both shrinkage performance that allows sufficient shrinkage at relatively low temperatures and good severing performance.

[0438] In the dicing die bonding film of the embodiment, the dicing tape comprises a first substrate layer comprising an ethylene-acrylic acid copolymer resin and a second substrate layer comprising an ethylene-vinyl acetate copolymer resin, with the second substrate layer being disposed between the first substrate layer and the adhesive layer of the dicing tape. Therefore, after the expansion process, the dicing tape can sufficiently shrink even when subjected to relatively low-temperature heating, thereby sufficiently suppressing the force exerted by the dicing tape to shrink. Therefore, it can be assumed that the dicing tape of the embodiment can shrink even when heated at a relatively low temperature after being stretched in the expansion process, thereby sufficiently maintaining the spacing (cut) between adjacent chips.

[0439] Industrial applicability

[0440] The dicing die-bonding film of the present invention can be suitably used as an auxiliary tool in manufacturing a semiconductor device (semiconductor integrated circuit), for example.

Claims

1. A dicing tape comprising a base layer and an adhesive layer superimposed on one side of the base layer, The substrate layer has a plurality of stacked layers, and the plurality of layers include at least a first substrate layer containing an ethylene-acrylic acid copolymer resin and a second substrate layer containing a resin other than the ethylene-acrylic acid copolymer resin, The second base layer is arranged between the first base layer and the adhesive layer.

2. The cutting tape according to claim 1, wherein: The second substrate layer contains at least ethylene-vinyl acetate copolymer resin.

3. The cutting tape according to claim 1 or 2, wherein: The substrate layer further comprises a third substrate layer comprising an ethylene-acrylic acid copolymer resin, The second base layer is arranged between the first base layer and the third base layer.

4. The cutting tape according to claim 1 or 2, wherein: The tensile storage modulus of the first substrate layer at 90°C is greater than the tensile storage modulus of the second substrate layer at 90°C.

5. The cutting tape according to claim 3, wherein: The tensile storage moduli of the first substrate layer and the third substrate layer at 90°C are both greater than the tensile storage modulus of the second substrate layer at 90°C.

6. The cutting tape according to claim 1 or 2, wherein: The absolute value of the difference between the melting point of the first base layer and the melting point of the second base layer is 10° C. or less.

7. The cutting tape according to claim 3, wherein: The maximum value among the absolute values ​​of the differences between the melting point of the first base layer or the third base layer and the melting point of the second base layer is 10° C. or less.

8. The cutting tape according to claim 1 or 2, wherein: The spectrum obtained by measuring the substrate layer by differential scanning calorimetry does not have an endothermic peak having a peak at a temperature of 100° C. or higher.

9. The cutting tape according to claim 1 or 2, wherein: The base material layer has a tensile storage modulus of 1.0 MPa or more at 90°C.

10. The dicing tape according to claim 1 or 2, which is used for manufacturing a semiconductor device. 11 . A dicing die-bonding film comprising the dicing tape according to claim 1 or 2 and a die-bonding sheet superimposed on the dicing tape.

12. A method for manufacturing a semiconductor device, wherein: A semiconductor device having a semiconductor chip is manufactured using a dicing die-bonding film, the dicing die-bonding film comprising the dicing tape according to claim 1 or 2, and a die-bonding sheet overlapped on the dicing tape, The method for manufacturing a semiconductor device comprises the following steps: a mounting step of placing the die bonding sheet between the adhesive layer of the dicing tape and the semiconductor wafer, thereby fixing the semiconductor wafer to the dicing tape via the die bonding sheet; as well as an expansion step of cutting the semiconductor wafer together with the die bonding sheet by stretching the dicing tape, thereby cutting the semiconductor wafer into small pieces to obtain a semiconductor chip group, In the method for manufacturing a semiconductor device, a portion of the stretched dicing tape is heated around the semiconductor chip group to shrink it.

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