Dicing tape and dicing die-bonding film

Abstract

The present invention relates to a dicing tape and a dicing die bonding film. A dicing tape or the like is provided, wherein the dicing tape comprises a base layer and an adhesive layer having higher adhesiveness than the base layer, wherein the base layer has a volume crystallinity of 20 J / cm calculated from a differential scanning calorimetry measurement result. 3 Above and 120J / cm 3 Below, and the thickness of the base material layer is 80 μm or more.

Description

Technical Field

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

[0002] In the past, a dicing die bonding film used in the manufacture of semiconductor integrated circuits is known. Such a dicing die bonding film, for example, comprises a dicing tape and a die bonding layer laminated on the dicing tape and bonded to a wafer. The dicing tape comprises a base material layer and an adhesive layer in contact with the die bonding layer. Such a dicing die bonding film is used in the manufacture of semiconductor integrated circuits, for example, as follows.

[0003] The method of manufacturing a semiconductor integrated circuit generally includes a front process of forming a circuit surface on one side of a wafer with a highly integrated electronic circuit, and a back process of cutting out chips from the wafer with the circuit surface formed thereon and assembling them.

[0004] The post-process includes the following processes, for example: a dicing process of forming grooves on the wafer in order to cut the wafer into small chips (die); a mounting process of attaching the surface of the wafer opposite to the circuit surface to the chip bonding layer and fixing the wafer to the dicing tape; an expansion process of cutting the wafer with the grooves formed together with the chip bonding layer to expand the interval between the chips; a pick-up process of peeling off the chip bonding layer and taking out the chip (die) with the chip bonding layer attached; a chip bonding process of attaching the chip (die) with the chip bonding layer attached to the adherend. Semiconductor integrated circuits are manufactured through these processes.

[0005] In the above manufacturing method, the expansion step is performed by, for example, stretching the dicing tape in a radial direction at a low temperature below freezing, such as in a state where a wafer is arranged on a chip bonding layer overlapping the dicing tape, and then stretching it at room temperature to expand the interval (cut) between adjacent chips (dies). Thereafter, in order to maintain the interval (cut), a portion of the dicing tape whose tension is reduced due to the stretching is heat shrunk. Specifically, the dicing tape on the outer side of the portion overlapping the cut chip (die) is heat shrunk, thereby maintaining the interval (cut).

[0006] However, in the expansion process performed under low temperature conditions, the semiconductor wafer and the chip bonding layer may not be cut at the same time. In order to prevent this problem, it is desired that the dicing tape has the performance of being able to well cut the semiconductor wafer through the expansion process under low temperature conditions.

[0007] In contrast, conventional dicing tapes have an initial elastic modulus of 200 MPa to 380 MPa at -10°C and a Tanδ (loss elastic modulus / storage elastic modulus) of 0.080 to 0.3 at -10°C (Patent Document 1).

[0008] According to the dicing tape described in Patent Document 1, when used in a state where a semiconductor wafer is bonded via a die bond layer, the semiconductor wafer and the die bond layer can be cut together by an expansion step performed under low temperature conditions.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Application Publication No. 2015-185591 Summary of the invention

[0012] Problem that the invention aims to solve

[0013] However, it can be said that sufficient research has not yet been conducted on dicing die-bonding films and dicing tapes that can satisfactorily cut semiconductor wafers in a low-temperature expansion process.

[0014] Therefore, an object of the present invention is to provide a dicing tape and a dicing die-bonding film capable of favorably dicing a semiconductor wafer in a low-temperature expansion process.

[0015] Solutions for solving problems

[0016] In order to solve the above-mentioned problems, the dicing tape according to the present invention is characterized in that it comprises a base layer and an adhesive layer having higher adhesiveness than the base layer.

[0017] The volume crystallinity of the substrate layer calculated from the differential scanning calorimetry results was 20 J / cm 3 Above and 120J / cm 3 Below, and the thickness of the base material layer is 80 μm or more.

[0018] The dicing tape having the above-mentioned structure can well separate the semiconductor wafer in the low-temperature expansion process.

[0019] The dicing tape preferably has an endothermic peak in a spectrum measured by differential scanning calorimetry of the substrate layer, and the peak temperature of the endothermic peak is 100° C. or higher. This has the advantage that mechanical energy due to expansion can be more efficiently transmitted in the substrate layer because the crystallinity of the substrate layer becomes higher.

[0020] The dicing die-bonding film according to the present invention comprises the dicing tape described above and a die-bonding layer attached to the dicing tape.

[0021] Effects of the Invention

[0022] According to the dicing tape and the dicing die-bonding film of the present invention, a semiconductor wafer can be favorably cut in a low-temperature expansion process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a cross-sectional view obtained by cutting the dicing die-bonding film of the present embodiment in the thickness direction.

[0024] Figure 2A The figure is a cross-sectional view schematically showing a half-cut process in a method of manufacturing a semiconductor integrated circuit.

[0025] Figure 2B The figure is a cross-sectional view schematically showing a half-cut process in a method of manufacturing a semiconductor integrated circuit.

[0026] Figure 2C The figure is a cross-sectional view schematically showing a half-cut process in a method of manufacturing a semiconductor integrated circuit.

[0027] Figure 2D The figure is a cross-sectional view schematically showing a half-cut process in a method of manufacturing a semiconductor integrated circuit.

[0028] Figure 3A It is a cross-sectional view schematically showing a mounting step in a method of manufacturing a semiconductor integrated circuit.

[0029] Figure 3B It is a cross-sectional view schematically showing a mounting step in a method of manufacturing a semiconductor integrated circuit.

[0030] Figure 4A This is a cross-sectional view schematically showing a state of a low-temperature expansion step in a method of manufacturing a semiconductor integrated circuit.

[0031] Figure 4B This is a cross-sectional view schematically showing a state of a low-temperature expansion step in a method of manufacturing a semiconductor integrated circuit.

[0032] Figure 4C This is a cross-sectional view schematically showing a state of a low-temperature expansion step in a method of manufacturing a semiconductor integrated circuit.

[0033] Figure 5A It is a cross-sectional view schematically showing a state of an expansion process at room temperature in a method for manufacturing a semiconductor integrated circuit.

[0034] Figure 5B It is a cross-sectional view schematically showing a state of an expansion process at room temperature in a method for manufacturing a semiconductor integrated circuit.

[0035] Figure 6 It is a cross-sectional view schematically showing a state of a pickup process in a method of manufacturing a semiconductor integrated circuit.

[0036] Fig. 7A This is a first spectrum diagram showing an example (Example 1) of differential scanning calorimetry.

[0037] Figure 7B This is a second spectrum diagram showing an example (Example 1) of differential scanning calorimetry.

[0038] Fig. 8A This is a first spectrum diagram showing an example (Comparative Example 1) of differential scanning calorimetry.

[0039] Figure 8B This is a second spectrum diagram showing an example (Comparative Example 1) of differential scanning calorimetry.

[0040] Description of Reference Numerals

[0041] 1: Cutting die bonding film,

[0042] 10: Chip bonding layer,

[0043] 20: cutting belt,

[0044] 21: base material layer,

[0045] 22: Adhesive layer. DETAILED DESCRIPTION

[0046] Hereinafter, one embodiment of the dicing die-bonding film and the dicing tape according to the present invention will be described with reference to the drawings.

[0047] The dicing die-bonding film 1 of the present embodiment includes a dicing tape 20 and a pressure-sensitive adhesive layer 22 laminated on the dicing tape 20 and a die-bonding layer 10 bonded to a semiconductor wafer.

[0048] The dicing tape 20 of this embodiment is usually a long sheet and is stored in a rolled state until use. The dicing die-bonding film 1 of this embodiment is attached to an annular frame having an inner diameter slightly larger than a silicon wafer to be cut and used after being cut.

[0049] The dicing tape 20 of the present embodiment includes a base layer 21 and a pressure-sensitive adhesive layer 22 superimposed on the base layer 21 .

[0050] In the dicing tape 20 of the present embodiment, the volume crystallinity of the base layer 21 calculated from the differential scanning calorimetry measurement result is 20 J / cm 3 Above and 120J / cm 3Below, and the thickness of the base material layer 21 is 80 μm or more.

[0051] Since the dicing tape 20 of the present embodiment has the above-described configuration, it is possible to favorably divide the semiconductor wafer in the low-temperature expansion step.

[0052] The volume crystallinity is a value obtained by subjecting the base material layer 21 to differential scanning calorimetry (DSC measurement) and based on the measurement results.

[0053] Specifically, differential scanning calorimetry (DSC measurement) of the base material layer 21 was performed under the following measurement conditions. From the spectrum obtained by one measurement, the volume crystallinity calculated as follows was determined.

[0054] Specifically, using a commercially available DSC measuring apparatus, about 10 mg of a sample was weighed, and the temperature was raised from room temperature (about 20°C) to 200°C at a heating rate of 5°C / min, and the measurement was performed in a nitrogen atmosphere. The sample was prepared by cutting the base layer 21 in the thickness direction.

[0055] The amount of heat absorbed is calculated from the area of ​​the endothermic peak appearing in the spectrum obtained by differential scanning calorimetry (DSC measurement). The area of ​​the endothermic peak is calculated by finding the area surrounded by the baseline formed by connecting the points on the low temperature side of the peak without heat change and the points on the high temperature side and the curve depicting the endothermic peak. The calculation of the amount of heat absorbed is based on the endothermic peak associated with melting. The calculated amount of heat absorbed is converted into a value per unit volume. It should be noted that, in the case where the substrate layer 21 is composed of multiple layers of different materials, multiple endothermic peaks sometimes appear in the measurement spectrum. When calculating the amount of heat absorbed, the amount of heat absorbed is calculated from the area of ​​each endothermic peak caused by each layer, and the value obtained by dividing the sum of the endothermic amounts by the total volume of the substrate layer 21 is used as the volume crystallinity of the substrate layer 21.

[0056] The area of ​​the endothermic peak appearing in the measurement spectrum was calculated using the analysis software attached to the DSC measurement apparatus.

[0057] In addition, although an exothermic peak or a curve based on the glass transition temperature may appear in the measurement spectrum, these are not regarded as endothermic peaks.

[0058] The analysis software included with the DSC measuring device measures the temperatures of the peak start point (hereinafter also referred to as point A), the peak apex (hereinafter also referred to as point C), and the peak end point (hereinafter also referred to as point B) of the endothermic peak appearing in the measurement spectrum.

[0059] It is most desirable to determine the area, peak start point, peak apex and peak end point of the endothermic peak based on the measurement results obtained using a specific DSC measuring apparatus described in the examples described below and using specific analysis software described in the examples described below.

[0060] If the above volume crystallinity is less than 20 J / cm 3 On the other hand, if the volume crystallinity is greater than 120 J / cm 3 , the crystallinity of the base layer 21 is too high, so the base layer 21 may be broken during expansion.

[0061] The above volume crystallinity is preferably 25 J / cm 3 More preferably 26 J / cm 3 More preferably, 30 J / cm 3 As a result, there is an advantage of achieving better cutting performance in the low-temperature expansion process.

[0062] The above volume crystallinity is preferably 100 J / cm 3 Below, more preferably 90 J / cm 3 Below, more preferably 82 J / cm 3 This has the advantage that the base material layer 21 is further prevented from being broken during expansion.

[0063] For example, the volume crystallinity can be further increased by forming the substrate layer 21 from a resin material having a higher crystallinity or performing a slow cooling treatment or a stretching treatment when manufacturing the substrate layer 21. On the other hand, the volume crystallinity can be further reduced by forming the substrate layer 21 from a resin material having a lower crystallinity or not performing a rapid cooling treatment or a stretching treatment when manufacturing the substrate layer 21.

[0064] The spectrum measured by differential scanning calorimetry (DSC) of the base material layer 21 preferably has an endothermic peak having a vertex (point C) in the range of 100° C. to 140° C. The endothermic peak is, for example, an endothermic peak that occurs with melting of the resin.

[0065] By making the apex (point C) of the endothermic peak above 100°C, it has the advantage of being able to quickly solidify after the heat shrinkage is completed and maintain the incision. In addition, it has the advantage of exhibiting better cutting properties. The apex (point C) of the endothermic peak is more preferably present at 105°C or above.

[0066] When the top of the endothermic peak (point C) is at 140° C. or lower, there is an advantage that sufficient heat shrinkage can occur during heat shrinkage. The top of the endothermic peak (point C) is more preferably at 135° C. or lower.

[0067] It should be noted that, when there are multiple endothermic peaks in the range of 100°C to 140°C, it is preferred that at least one of the endothermic peaks satisfies the above conditions (peak apex). Similarly, it is preferred that at least one endothermic peak satisfies the following conditions (peak start point, end point, etc.).

[0068] For example, the top of the endothermic peak (point C) can be shifted to a higher temperature by forming the base material layer 21 with a resin material having a higher melting point, or by using a layer of a resin material having a higher melting point to constitute the base material layer 21 of a laminated structure, or by compounding (blending) a resin material having a higher melting point into the base material layer 21. On the other hand, for example, by forming the base material layer 21 with a resin material having a lower melting point, or by using a layer of a resin material having a lower melting point to constitute the base material layer 21 of a laminated structure, or by compounding (blending) a resin material having a lower melting point into the base material layer 21, the temperature of the top of the endothermic peak (point C) can be shifted to a lower temperature.

[0069] The temperature difference between the peak starting point (point A) and the top point (point C) in the endothermic peak is preferably 40° C. or less, more preferably 35° C. or less.

[0070] By making the temperature difference below 40°C, the melting of the base layer 21 can be completed with a smaller (narrower) temperature difference. Therefore, the solidification and softening of the base layer 21 can be achieved with a smaller temperature difference. Therefore, by causing the base layer 21 to heat shrink after expansion and quickly solidifying after the heat shrinkage, the interval (cut) between adjacent chips (dies) can be efficiently maintained.

[0071] The temperature difference between the peak start point (point A) and the top point (point C) in the endothermic peak may be 20° C. or more.

[0072] For example, by further increasing the molecular weight dispersion of the resin (polymer) contained in the base material layer 21 , the temperature difference between the peak start point (point A) and the top point (point C) in the endothermic peak can be further increased.

[0073] For example, by further reducing the molecular weight dispersion of the resin (polymer) included in the base material layer 21 , the temperature difference between the peak start point (point A) and the top point (point C) in the endothermic peak can be further reduced.

[0074] For the above-mentioned dicing tape, in the above-mentioned endothermic peak of the base layer 21, the temperature difference between the peak start point (point A) and the peak end point (point B) is preferably 60°C or less, more preferably 50°C or less. By making the temperature difference 60°C or less, the temperature difference from the start of melting to the end of melting of the base layer 21 becomes smaller, so that the base layer 21 can be solidified and softened with a smaller temperature difference. Therefore, there is an advantage that the above-mentioned heat shrinkage performed after expansion can be efficiently implemented.

[0075] The temperature difference may be 30° C. or more.

[0076] For example, the temperature difference between the peak start point (point A) and the peak end point (point B) can be further reduced by further reducing the molecular weight dispersion of the resin (polymer) contained in the base layer 21. On the other hand, for example, by further increasing the molecular weight dispersion of the resin (polymer) contained in the base layer 21, the temperature difference between the peak start point (point A) and the peak end point (point B) can be further increased.

[0077] For the above-mentioned dicing tape, in the above-mentioned endothermic peak of the base layer 21, the temperature of the peak starting point (point A) is preferably 70°C or more, more preferably 80°C or more. The peak starting point (point A) is an indicator of the temperature at which the base layer 21 ends solidification. By making the temperature of the peak starting point above 70°C, the base layer 21 temporarily softened by the heater begins to cool and ends solidification at a higher temperature. If the temperature is lower than 70°C, the solidification of the base layer 21 ends, so the above-mentioned heat shrinkage after expansion can be fully performed. Therefore, the incision can be efficiently maintained in a good state after expansion.

[0078] The temperature of the peak starting point (point A) may be 110° C. or lower, or 100° C. or lower.

[0079] For example, the temperature of the peak starting point (point A) can be shifted to a higher temperature by forming the base material layer 21 from a resin material having a higher melting point, or by using a layer of a resin material having a higher melting point to constitute the base material layer 21 of a laminated structure, or by compounding (blending) a resin material having a higher melting point into the base material layer 21. On the other hand, for example, by forming the base material layer 21 from a resin material having a lower melting point, or by using a layer of a resin material having a lower melting point to constitute the base material layer 21 of a laminated structure, or by compounding (blending) a resin material having a lower melting point into the base material layer 21, the temperature of the peak starting point (point A) can be shifted to a lower temperature.

[0080] For the above-mentioned dicing tape, in the above-mentioned endothermic peak of the base layer 21, the temperature of the peak end point (point B) is preferably 150°C or less, and more preferably 140°C or less. The peak end point (point B) is an indicator of the temperature at which the base layer 21 ends softening. By setting the temperature of the peak end point to 150°C or less, even if the heating temperature of the heater is slightly lower, as long as the temperature is higher than 150°C, the base layer 21 will be sufficiently softened. Therefore, even if the heating temperature for softening is slightly low, the above-mentioned heat shrinkage can be efficiently implemented, so that the incision can be efficiently maintained in a good state after expansion.

[0081] The temperature at the peak end point (point B) may be 110° C. or higher, or 120° C. or higher.

[0082] For example, the temperature of the peak end point (point B) can be shifted to a lower temperature by forming the base material layer 21 from a resin material having a lower melting point, or by using a layer of a resin material having a lower melting point to constitute the base material layer 21 of a laminated structure, or by compounding (blending) a resin material having a lower melting point into the base material layer 21. On the other hand, for example, by forming the base material layer 21 from a resin material having a higher melting point, or by using a layer of a resin material having a higher melting point to constitute the base material layer 21 of a laminated structure, or by compounding (blending) a resin material having a higher melting point into the base material layer 21, the temperature of the peak end point (point B) can be shifted to a higher temperature.

[0083] The base material layer 21 may have a single-layer structure or a laminated structure.

[0084] Each layer of the base material layer 21 is, for example, a metal foil, a fiber sheet such as paper or cloth, a rubber sheet, a resin film, or the like.

[0085] Examples of the fiber sheet constituting the base layer 21 include paper, woven fabric, and nonwoven fabric.

[0086] As the material of the resin film, for example, polyolefins such as polyethylene (PE), polypropylene (PP), and ethylene-propylene copolymers; ethylene copolymers such as ethylene-vinyl acetate copolymers (EVA), ionomer resins, ethylene-(meth)acrylic acid copolymers, and ethylene-(meth)acrylate (random, alternating) copolymers; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); polyacrylates; polyvinyl chloride (PVC); polyurethane; polycarbonate; polyphenylene sulfide (PPS); polyamides such as aliphatic polyamides and wholly aromatic polyamides (aramid); polyetheretherketone (PEEK); polyimide; polyetherimide; polyvinylidene chloride; ABS (acrylonitrile-butadiene-styrene copolymer); cellulose or cellulose derivatives; silicone-containing polymers; fluorine-containing polymers, etc. These can be used alone or in combination of two or more.

[0087] The base material layer 21 is preferably made of a polymer material such as a resin film.

[0088] When the base material layer 21 includes a resin film, the resin film may be subjected to a stretching treatment or the like to control deformability such as elongation.

[0089] The surface of the base material layer 21 may be subjected to a surface treatment in order to improve adhesion with the adhesive layer 22. As the surface treatment, for example, an oxidation treatment based on a chemical method or a physical method such as chromic acid treatment, ozone exposure, flame exposure, high voltage electric shock exposure, ionizing radiation treatment, etc. may be adopted. In addition, a coating treatment based on a coating agent such as an anchor coating agent, a primer, an adhesive, etc. may be performed.

[0090] The base material layer 21 is preferably composed of a plurality of layers, more preferably composed of at least three layers, and even more preferably composed of three layers.

[0091] By making the base material layer 21 have a stacked structure of multiple layers (for example, a three-layer structure), a layer with a higher elastic modulus can be stacked with a layer with a lower elastic modulus, so there is an advantage that the elastic modulus of the base material layer 21 can be controlled more easily. For example, in the case of a base material layer having only a layer with a higher elastic modulus, the chip sometimes floats and the base material breaks during the expansion process. In addition, for example, in the case of a base material layer having only a layer with a lower elastic modulus, sufficient stress for cutting by expansion sometimes cannot be transmitted to the base material layer.

[0092] The three-layered substrate layer 21 preferably includes two non-elastic layers (X, X) formed of a non-elastic body and an elastic layer (Y) formed of an elastomer and disposed between the two non-elastic layers (X layer / Y layer / X layer).

[0093] The elastic layer is a layer having an elastic modulus of 200 MPa or less at room temperature. The elastic layer is generally formed of a polymer material showing rubber elasticity at room temperature (23° C.). On the other hand, the non-elastic layer is a layer having an elastic modulus of more than 200 MPa at room temperature.

[0094] Each layer of the elastic body having such a three-layer laminated structure is usually formed of a resin. The elastic body having a three-layer laminated structure is produced by, for example, co-extrusion molding, and the three layers are integrated.

[0095] In the three-layered base material layer 21 , the ratio of the thickness of the inner layer to the thickness of one outer layer (Y thickness / X thickness) is preferably 5 or more and 15 or less.

[0096] The non-elastic layer disposed outside has a melting point of, for example, 100° C. to 140° C. The non-elastic layer preferably has a molecular weight distribution dispersion (mass average molecular weight / number average molecular weight) of 3 or less when the constituent resin is measured by GPC.

[0097] The non-elastomer layer (X) may include low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene, etc. As polypropylene, homopolymers (homopolypropylene) or copolymers such as random polypropylene and block polypropylene may be listed. Polypropylene may be metallocene polypropylene synthesized using a metallocene catalyst. The non-elastomer layer (X) preferably includes metallocene polypropylene.

[0098] On the other hand, the elastomer layer (Y) preferably comprises ethylene-vinyl acetate copolymer (EVA) or α-olefin-based thermoplastic elastomer, and more preferably comprises ethylene-vinyl acetate copolymer (EVA). Examples of α-olefin-based thermoplastic elastomers include homopolymers of α-olefins and copolymers of two or more α-olefins.

[0099] The ethylene-vinyl acetate copolymer resin (EVA) may contain 5% by mass or more and 35% by mass or less of a vinyl acetate structural unit.

[0100] The thickness (total thickness) of the substrate layer 21 is 80 μm or more. The thickness may exceed 100 μm. The thickness may be 150 μm or less. The value is the average value of the measured values ​​of at least 3 randomly selected points. Hereinafter, the thickness of the adhesive layer 22 is also taken as the average value.

[0101] If the thickness of the base layer 21 is less than 80 μm, stress may not be uniformly applied to the entire base layer 21 , and good splitting properties may not be exhibited in the low-temperature expansion step.

[0102] 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.

[0103] The base material layer 21 is preferably a light-transmitting (ultraviolet-transmitting) resin film or the like, from the viewpoint of being able to provide active energy rays such as ultraviolet rays to the pressure-sensitive adhesive layer 22 from the back side.

[0104] The dicing tape 20 of this embodiment may have a release sheet covering one side of the adhesive layer 22 (the side of the adhesive layer 22 that does not overlap with the base layer 21) before use. When the die bonding layer 10 having a smaller area than the adhesive layer 22 is arranged so as to be contained in the adhesive layer 22, the release sheet is arranged so as to cover both the adhesive layer 22 and the die bonding layer 10. The release sheet is used to protect the adhesive layer 22 and is peeled off before the die bonding layer 10 is attached to the adhesive layer 22.

[0105] As the release sheet, for example, a plastic film or paper that has been surface-treated with a release agent such as a silicone-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide release agent can be used.

[0106] In addition, as a release sheet, films made of fluorine-based polymers such as polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, and chlorofluoroethylene-vinylidene fluoride copolymer; films made of polyolefins such as polyethylene and polypropylene; and films made of polyesters such as polyethylene terephthalate (PET).

[0107] As the release sheet, for example, a plastic film or paper whose surface is coated with a release agent such as a fluorine-based release agent or a long-chain alkyl acrylate-based release agent can be used.

[0108] It should be noted that the release sheet can be used as a supporting material for supporting the adhesive layer 22. In particular, the release sheet can be used appropriately when the adhesive layer 22 is overlapped on the base layer 21. Specifically, the adhesive layer 22 can be overlapped on the base layer 21 by overlapping the adhesive layer 22 on the base layer 21 in a state where the release sheet and the adhesive layer 22 are stacked, and peeling (transferring) the release sheet after overlapping, so that the adhesive layer 22 can be overlapped on the base layer 21.

[0109] In the present embodiment, the adhesive layer 22 contains, for example, an acrylic polymer, an isocyanate compound, and a polymerization initiator.

[0110] The adhesive layer 22 preferably has a thickness of 5 μm or more and 40 μm or less. The shape and size of the adhesive layer 22 are usually the same as those of the base material layer 21 .

[0111] In the dicing tape 20 of the present embodiment, the ratio of the thickness of the adhesive layer 22 to the total thickness of the dicing tape 20 may be 5% or more and 30% or less.

[0112] The acrylic polymer has at least a structural unit of an alkyl (meth)acrylate, a structural unit of a hydroxyl group-containing (meth)acrylate, and a structural unit of a (meth)acrylate containing a polymerizable group in the molecule. The structural unit is a unit constituting the main chain of the acrylic polymer. Each side chain in the acrylic polymer is included in each structural unit constituting the main chain.

[0113] In addition, in this specification, the expression "(meth)acrylate" means at least one of methacrylate and acrylate. Similarly, the expression "(meth)acrylic acid" means at least one of methacrylic acid and acrylic acid.

[0114] In the acrylic polymer contained in the adhesive layer 22, the above structural units can be1 H-NMR, 13 The molar ratio of the above structural units in the acrylic polymer is usually calculated from the amount of the acrylic polymer blended (charged amount) during polymerization.

[0115] The structural unit of the alkyl (meth)acrylate is derived from the alkyl (meth)acrylate monomer. In other words, the molecular structure after the polymerization reaction of the alkyl (meth)acrylate monomer is the structural unit of the alkyl (meth)acrylate. The term "alkyl" indicates the number of carbon atoms in the hydrocarbon part that forms an ester bond with (meth)acrylic acid.

[0116] The hydrocarbon portion of the alkyl portion in the structural unit of the alkyl (meth)acrylate may be a saturated hydrocarbon or an unsaturated hydrocarbon.

[0117] It should be noted that the alkyl portion preferably does not contain polar groups containing oxygen (O), nitrogen (N), etc. Thus, the polarity of the alkyl polymer can be suppressed from being extremely increased. Therefore, the adhesive layer 22 can be suppressed from having excessive affinity with respect to the chip bonding layer 10. Thus, the dicing tape 20 can be peeled off better from the chip bonding layer 10. The number of carbon atoms in the alkyl portion can be greater than 6 and less than 10.

[0118] Examples of the structural unit of the alkyl (meth)acrylate include structural units of hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, and decyl (meth)acrylate.

[0119] The acrylic polymer has a structural unit of a hydroxyl group-containing (meth)acrylate, and the hydroxyl group of the structural unit is easily reactive with an isocyanate group.

[0120] By allowing the acrylic polymer having a structural unit of a hydroxyl-containing (meth)acrylate and the isocyanate compound to coexist in the adhesive layer 22 in advance, the adhesive layer 22 can be appropriately cured. Therefore, the acrylic polymer can be fully gelled. Therefore, the adhesive layer 22 can exhibit adhesive properties while maintaining its shape.

[0121] The structural unit of the hydroxyl-containing (meth)acrylate is preferably a structural unit of a hydroxyl-containing C2-C4 (meth)acrylate alkyl ester. The expression "C2-C4 alkyl" indicates the number of carbon atoms of the hydrocarbon part that forms an ester bond with (meth)acrylic acid. In other words, the hydroxyl-containing C2-C4 (meth)acrylate alkyl ester monomer refers to a monomer obtained by forming an ester bond between (meth)acrylic acid and an alcohol (usually a diol) having 2 to 4 carbon atoms.

[0122] The hydrocarbon portion of the C2-C4 alkyl group is usually a saturated hydrocarbon. For example, the hydrocarbon portion of the C2-C4 alkyl group is a straight-chain saturated hydrocarbon or a branched saturated hydrocarbon. The hydrocarbon portion of the C2-C4 alkyl group preferably does not contain a polar group containing oxygen (O), nitrogen (N), etc.

[0123] As the structural unit of the hydroxyl-containing C2-C4 (meth) alkyl ester, for example, structural units of hydroxybutyl (meth) acrylate such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxyn-butyl (meth) acrylate, or hydroxyisobutyl (meth) acrylate can be cited. It should be noted that in the structural unit of hydroxybutyl (meth) acrylate, the hydroxyl group (-OH group) may be bonded to the carbon (C) at the terminal of the hydrocarbon part, or may be bonded to the carbon (C) other than the terminal of the hydrocarbon part.

[0124] The acrylic polymer includes a structural unit of a polymerizable group-containing (meth)acrylate having a polymerizable unsaturated double bond in a side chain.

[0125] By making the acrylic polymer contain a structural unit of a (meth)acrylate containing a polymerizable group, the adhesive layer 22 can be cured by irradiating active energy rays (ultraviolet rays, etc.) before the pickup process. In detail, by irradiating active energy rays such as ultraviolet rays, free radicals are generated by a photopolymerization initiator, and the acrylic polymers can be cross-linked by the action of the free radicals. As a result, the adhesive force of the adhesive layer 22 before irradiation can be reduced by irradiation. In addition, the chip bonding layer 10 can be well peeled off from the adhesive layer 22.

[0126] In addition, as active energy rays, ultraviolet rays, radiation rays, and electron rays can be used.

[0127] Specifically, the structural unit of the polymerizable group-containing (meth)acrylate may have a molecular structure in which a hydroxyl group in the structural unit of the hydroxyl group-containing (meth)acrylate and an isocyanate group of an isocyanate group-containing (meth)acrylate monomer form a urethane bond.

[0128] The structural unit of the polymerizable group-containing (meth)acrylate having a polymerizable group can be prepared after polymerization of an acrylic polymer. For example, after copolymerization of an alkyl (meth)acrylate monomer and a hydroxyl-containing (meth)acrylate monomer, the hydroxyl group in a part of the structural units of the hydroxyl-containing (meth)acrylate is subjected to a urethanization reaction with the isocyanate group in the isocyanate-containing polymerizable monomer, thereby obtaining the structural unit of the polymerizable group-containing (meth)acrylate.

[0129] The isocyanate group-containing (meth)acrylate monomer preferably has one isocyanate group and one (meth)acryloyl group in the molecule. Examples of such monomers include 2-(meth)acryloyloxyethyl isocyanate (2-isocyanatoethyl (meth)acrylate).

[0130] The adhesive layer 22 of the dicing tape 20 in the present embodiment further contains an isocyanate compound. A part of the isocyanate compound may be in a state after reacting by a urethanization reaction or the like.

[0131] The isocyanate compound has a plurality of isocyanate groups in the molecule. By making the isocyanate compound have a plurality of isocyanate groups in the molecule, a cross-linking reaction can be performed between the acrylic polymers in the adhesive layer 22. Specifically, by making one isocyanate group of the isocyanate compound react with a hydroxyl group of the acrylic polymer, and making the other isocyanate groups react with hydroxyl groups of other acrylic polymers, a cross-linking reaction can be performed with the isocyanate compound.

[0132] Examples of the isocyanate compound include diisocyanates such as aliphatic diisocyanates, alicyclic diisocyanates, and aromatic aliphatic diisocyanates.

[0133] Furthermore, examples of the isocyanate compound include polymeric polyisocyanates such as dimers and trimers of diisocyanates; and polymethylene polyphenylene polyisocyanates.

[0134] The isocyanate compound includes, for example, polyisocyanates obtained by reacting an excess of the above isocyanate compound with a compound containing active hydrogen. The compound containing active hydrogen includes low molecular weight compounds containing active hydrogen, high molecular weight compounds containing active hydrogen, and the like.

[0135] In addition, as an isocyanate compound, allophanate polyisocyanate, biuret polyisocyanate, etc. can also be used.

[0136] The above isocyanate compounds can be used alone or in combination of two or more.

[0137] As the above-mentioned isocyanate compound, the reaction product of an aromatic diisocyanate and a low molecular weight compound containing active hydrogen is preferred. The reaction rate of the isocyanate group in the reaction product of the aromatic diisocyanate is slow, so over-curing of the adhesive layer 22 containing the reaction product is suppressed. As the above-mentioned isocyanate compound, an isocyanate compound having three or more isocyanate groups in the molecule is preferred.

[0138] The polymerization initiator contained in the adhesive layer 22 is a compound that can initiate a polymerization reaction by applying heat energy or light energy. By making the adhesive layer 22 contain a polymerization initiator, when heat energy or light energy is applied to the adhesive layer 22, a cross-linking reaction can be caused between acrylic polymers. In detail, a polymerization reaction between polymerizable groups can be initiated between acrylic polymers having structural units of (meth)acrylate containing polymerizable groups, thereby curing the adhesive layer 22. As a result, the adhesive force of the adhesive layer 22 can be reduced, and the chip bonding layer 10 can be easily peeled off from the cured adhesive layer 22 in the pickup process.

[0139] 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.

[0140] The adhesive layer 22 may further contain other components in addition to the above components. Examples of other components include tackifiers, plasticizers, fillers, antioxidants, antioxidants, ultraviolet absorbers, light stabilizers, heat stabilizers, antistatic agents, surfactants, and light peeling agents. The types and amounts of other components may be appropriately selected according to the purpose.

[0141] Next, the dicing die-bonding film 1 according to the present embodiment will be described in detail.

[0142] The dicing die-bonding film 1 of the present embodiment includes the dicing tape 20 and a die-bonding layer 10 laminated on the adhesive layer 22 of the dicing tape 20. The die-bonding layer 10 is bonded to a semiconductor wafer in the manufacture of a semiconductor integrated circuit.

[0143] The die bonding layer 10 may include at least one of a thermosetting resin and a thermoplastic resin. The die bonding layer 10 preferably includes a thermosetting resin and a thermoplastic resin.

[0144] Examples of thermosetting resins include epoxy resins, phenolic resins, amino resins, unsaturated polyester resins, polyurethane resins, silicone resins, and thermosetting polyimide resins. As the thermosetting resins, only one type or two or more types may be used. From the perspective of containing fewer ionic impurities that may cause corrosion of the semiconductor chip to be bonded to the chip, the thermosetting resin is preferably an epoxy resin. As a curing agent for the epoxy resin, a phenolic resin is preferably used.

[0145] Examples of the epoxy resin include bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolac type, o-cresol novolac type, trihydroxyphenylmethane type, tetrahydroxyphenylethane type, hydantoin type, triglycidyl isocyanurate type, and glycidylamine type epoxy resins.

[0146] The phenolic resin can function as a curing agent for the epoxy resin. Examples of the phenolic resin include novolac-type phenolic resins, resol-type phenolic resins, and polyoxystyrene such as polyoxystyrene.

[0147] Examples of the novolac-type phenolic resin include phenol novolac resins, phenol aralkyl resins, cresol novolac resins, tert-butylphenol novolac resins, and nonylphenol novolac resins.

[0148] As the phenol resin, only one type may be used or two or more types may be used.

[0149] In the die bonding layer 10 , the hydroxyl group of the phenol resin is preferably 0.5 to 2.0 equivalents, more preferably 0.7 to 1.5 equivalents per 1 equivalent of the epoxy group of the epoxy resin. This allows sufficient curing reaction between the epoxy resin and the phenol resin.

[0150] When the die bonding layer 10 includes a thermosetting resin, the content ratio of the thermosetting resin in the die bonding layer 10 is preferably 5% by mass or more and 60% by mass or less, and more preferably 10% by mass or more and 50% by mass or less relative to the total mass of the die bonding layer 10. Thus, the function as a thermosetting adhesive can be appropriately exhibited in the die bonding layer 10.

[0151] Examples of thermoplastic resins that may be included in the chip bonding layer 10 include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylate copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resins such as 6-nylon and 6,6-nylon (trade name); saturated polyester resins such as phenoxy resin, acrylic resin, PET, and PBT; polyamide-imide resins, fluororesins, and the like.

[0152] As the thermoplastic resin, an acrylic resin is preferred because it contains less ionic impurities and has high heat resistance, thereby further ensuring the adhesiveness of the die-bonding layer 10 .

[0153] As the above-mentioned thermoplastic resin, only one kind may be used or two or more kinds may be used.

[0154] The acrylic resin is preferably a polymer in which the structural unit of the (meth)acrylic acid alkyl ester is the largest in terms of mass ratio among the structural units in the molecule. Examples of the (meth)acrylic acid alkyl ester include C2 to C4 (meth)acrylic acid alkyl esters.

[0155] The acrylic resin may include a structural unit derived from other monomer components copolymerizable with the alkyl (meth)acrylate monomer.

[0156] Examples of the other monomer components include carboxyl group-containing monomers, acid anhydride monomers, hydroxyl group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, functional group-containing monomers such as acrylamide and acrylonitrile, and other various polyfunctional monomers.

[0157] From the perspective of being able to exert a higher cohesive force in the chip bonding layer 10, the above-mentioned acrylic resin is preferably a copolymer of an alkyl (meth)acrylate (especially an alkyl (meth)acrylate having an alkyl part with 4 or less carbon atoms) and a carboxyl group-containing monomer and a nitrogen atom-containing monomer and a polyfunctional monomer (especially a polyglycidyl-based polyfunctional monomer), and more preferably a copolymer of ethyl acrylate, butyl acrylate, acrylic acid, acrylonitrile and polyglycidyl (meth)acrylate.

[0158] The glass transition temperature (Tg) of the acrylic resin is preferably -50°C to 50°C, more preferably 10°C to 30°C, in order to easily set the elasticity and viscosity of the die-bonding layer 10 within a desired range.

[0159] When the die bonding layer 10 includes a thermosetting resin and a thermoplastic resin, the content ratio of the above-mentioned thermoplastic resin in the die bonding layer 10 is preferably 30 mass % or more and 70 mass % or less, more preferably 40 mass % or more and 60 mass % or less, and further preferably 45 mass % or more and 55 mass % or less relative to the total mass of the organic components other than the filler (e.g., thermosetting resin, thermoplastic resin, curing catalyst, silane coupling agent, dye). It should be noted that the elasticity and viscosity of the die bonding layer 10 can be adjusted by changing the content ratio of the thermosetting resin.

[0160] When the thermoplastic resin of the chip bonding layer 10 has a thermosetting functional group, as the thermoplastic resin, for example, an acrylic resin containing a thermosetting functional group can be used. The acrylic resin containing a thermosetting functional group preferably contains a structural unit derived from an alkyl (meth)acrylate in the molecule at the largest mass ratio. As the alkyl (meth)acrylate, for example, the alkyl (meth)acrylate esters exemplified above can be cited.

[0161] On the other hand, examples of the thermosetting functional group in the thermosetting functional group-containing acrylic resin include a glycidyl group, a carboxyl group, a hydroxyl group, and an isocyanate group.

[0162] The die bonding layer 10 preferably comprises an acrylic resin containing a thermosetting functional group and a curing agent. When the thermosetting functional group in the acrylic resin containing a thermosetting functional group is a glycidyl group, a compound having a plurality of phenol structures is preferably used as the curing agent. For example, the various phenolic resins described above can be used as the curing agent.

[0163] The die bond layer 10 preferably contains a filler. By changing the amount of the filler in the die bond layer 10, the elasticity and viscosity of the die bond layer 10 can be more easily adjusted. Furthermore, the physical properties of the die bond layer 10, such as electrical conductivity, thermal conductivity, and elastic modulus, can be adjusted.

[0164] Examples of the filler include inorganic fillers and organic fillers. As the filler, an inorganic filler is preferred.

[0165] Examples of inorganic fillers include fillers such as aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, boron nitride, crystalline silicon dioxide, amorphous silicon dioxide, and silicon dioxide. In addition, examples of inorganic fillers include metal single substances such as aluminum, gold, silver, copper, and nickel; alloys, etc. Fillers such as aluminum borate whiskers, amorphous carbon black, and graphite may be used. The shape of the filler may be various shapes such as spherical, needle-shaped, and flaky. As fillers, only one of the above may be used or two or more may be used.

[0166] The average particle size of the filler is preferably 0.005 μm or more and 10 μm or less, more preferably 0.005 μm or more and 1 μm or less. By making the average particle size 0.005 μm or more, the wettability and adhesion to adherends such as semiconductor wafers are further improved. By making the average particle size 10 μm or less, the characteristics brought by the added filler can be more fully utilized, and the heat resistance of the chip bonding layer 10 can be further utilized. The average particle size of the filler can be obtained, for example, using a photometric particle size distribution meter (for example, the product name is "LA-910", manufactured by Horiba, Ltd.).

[0167] When the die bonding layer 10 contains fillers, the content ratio of the fillers is preferably 30 mass % to 70 mass % relative to the total mass of the die bonding layer 10 , more preferably 40 mass % to 60 mass %, and further preferably 42 mass % to 55 mass %.

[0168] The die bonding layer 10 may contain other components as necessary. Examples of the other components include a curing catalyst, a flame retardant, a silane coupling agent, an ion scavenger, and a dye.

[0169] Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resins.

[0170] Examples of the silane coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane.

[0171] Examples of the ion scavenger include hydrotalcites, bismuth hydroxide, and benzotriazole.

[0172] As the other additives, only one kind may be used or two or more kinds may be used.

[0173] From the viewpoint of facilitating adjustment of elasticity and viscosity, the die-bonding layer 10 preferably contains a thermoplastic resin (particularly an acrylic resin), a thermosetting resin, and a filler.

[0174] The thickness of the die bonding layer 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 100 μm. When the die bonding layer 10 is a laminate, the thickness is the total thickness of the laminate.

[0175] The glass transition temperature (Tg) of the die bond layer 10 is preferably 0° C. or higher, more preferably 10° C. or higher. By setting the glass transition temperature to 0° C. or higher, the die bond layer 10 can be easily cut by low temperature expansion. The upper limit of the glass transition temperature of the die bond layer 10 is, for example, 100° C.

[0176] The chip bonding layer 10 may be, for example, Figure 1 In the present specification, a single layer means a layer having only one 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.

[0177] On the other hand, the die-bonding layer 10 may have a multilayer structure in which layers formed of two or more different compositions are stacked, for example.

[0178] When the dicing die bonding film 1 of the present embodiment is used, the adhesive layer 22 is cured by irradiating active energy rays (e.g., ultraviolet rays). Specifically, in a state where the die bonding layer 10 having a semiconductor wafer bonded to one surface and the adhesive layer 22 bonded to the other surface of the die bonding layer 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 arranged, and the ultraviolet rays or the like that have passed through the base layer 21 reach the adhesive layer 22. The adhesive layer 22 is cured by irradiation with ultraviolet rays or the like.

[0179] Since the adhesive layer 22 is cured after irradiation, the adhesive force of the adhesive layer 22 can be reduced, and thus the die bond layer 10 (the state where the semiconductor wafer is bonded) can be relatively easily peeled from the adhesive layer 22 after irradiation.

[0180] The dicing die bonding film 1 of the present embodiment may have a release sheet covering one surface of the die bonding layer 10 (the surface of the die bonding layer 10 that does not overlap with the adhesive layer 22) before use. The release sheet is used to protect the die bonding layer 10 and is peeled off before an adherend (e.g., a semiconductor wafer) is attached to the die bonding layer 10.

[0181] As the release sheet, the same release sheet as the above-mentioned release sheet can be used. The release sheet can be used as a supporting material for supporting the chip bonding layer 10. When the chip bonding layer 10 is overlapped on the adhesive layer 22, the release sheet can be appropriately used. In detail, the chip bonding layer 10 can be overlapped on the adhesive layer 22 by overlapping the chip bonding layer 10 on the adhesive layer 22 in a state where the release sheet and the chip bonding layer 10 are stacked, and the release sheet is peeled off (transferred) after overlapping, so that the chip bonding layer 10 can be overlapped on the adhesive layer 22.

[0182] Since the dicing die-bonding film 1 of the present embodiment is configured as described above, the semiconductor wafer can be favorably divided in the low-temperature expansion step described later.

[0183] Next, a method for manufacturing the dicing tape 20 and the dicing die-bonding film 1 according to the present embodiment will be described.

[0184] The method for manufacturing the dicing die-bonding film 1 according to the present embodiment includes:

[0185] A step of manufacturing the dicing tape 20 (a method of manufacturing the dicing tape), and a step of stacking the die bond layer 10 on the manufactured dicing tape 20 to manufacture the dicing die bond film 1 .

[0186] A method for manufacturing a cutting tape (a process for manufacturing a cutting tape) comprises:

[0187] A synthesis process for synthesizing acrylic polymers;

[0188] A step of producing an adhesive layer 22 by volatilizing a solvent from an adhesive composition comprising the acrylic polymer, an isocyanate compound, a polymerization initiator, a solvent, and other components appropriately added according to the purpose;

[0189] a base material layer manufacturing step of manufacturing the base material layer 21; and

[0190] The 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 .

[0191] In the synthesis step, for example, a (meth)acrylic acid C9-C11 alkyl ester monomer and a hydroxyl group-containing (meth)acrylic acid ester monomer are radically polymerized to synthesize an acrylic polymer intermediate.

[0192] The free radical polymerization can be carried out by a common method. For example, the acrylic polymer intermediate can be synthesized by dissolving the above-mentioned monomers in a solvent, stirring while heating, and adding a polymerization initiator. In order to adjust the molecular weight of the acrylic polymer, the polymerization can also be carried out in the presence of a chain transfer agent.

[0193] Next, a part of the hydroxyl groups of the structural unit of the hydroxyl-containing (meth)acrylate contained in the acrylic polymer intermediate is bonded to the isocyanate group of the isocyanate group-containing polymerizable monomer by urethanization reaction. Thus, a part of the structural unit of the hydroxyl-containing (meth)acrylate becomes a structural unit of the polymerizable group-containing (meth)acrylate.

[0194] The urethanization reaction can be carried out by a common method. For example, the acrylic polymer intermediate and the isocyanate group-containing polymerizable monomer are stirred while being heated in the presence of a solvent and a urethanization catalyst. In this way, the isocyanate group of the isocyanate group-containing polymerizable monomer can form a urethanate bond with a part of the hydroxyl groups of the acrylic polymer intermediate.

[0195] In the adhesive layer preparation process, for example, an acrylic polymer, an isocyanate compound and a polymerization initiator are dissolved in a solvent to prepare an adhesive composition. The viscosity of the composition can be adjusted by changing the amount of solvent. Next, the adhesive composition is applied to a release sheet. As a coating method, common coating methods such as roller coating, screen coating, gravure coating, etc. are adopted. By implementing a desolventizing treatment, a curing treatment, etc. to the applied composition, the applied adhesive composition is cured to prepare an adhesive layer 22.

[0196] In the substrate layer preparation step, the substrate layer 21 can be prepared by film formation by a common method. As the film formation method, for example, a calendering film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T-die extrusion method, a dry lamination method, etc. can be listed. A coextrusion molding method can be adopted. It should be noted that, as the substrate layer 21, a commercially available film, etc. can be used.

[0197] In the lamination step, the pressure-sensitive adhesive layer 22 in a state of being overlapped with the release sheet is overlapped with the base layer 21. In addition, the release sheet may be in a state of being overlapped with the pressure-sensitive adhesive layer 22 until use.

[0198] In order to promote the reaction between the crosslinking agent and the acrylic polymer 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.

[0199] Through these steps, the dicing tape 20 can be manufactured.

[0200] A method for manufacturing a dicing die-bonding film (a step of manufacturing a dicing die-bonding film) comprises:

[0201] a resin composition preparation step of preparing a resin composition for forming the die bonding layer 10;

[0202] a die bonding layer manufacturing process of manufacturing the die bonding layer 10 from the resin composition; and

[0203] A step of attaching the die bond layer 10 to the adhesive layer 22 of the dicing tape 20 manufactured as described above is performed.

[0204] In the resin composition preparation process, for example, an epoxy resin, a curing catalyst for the epoxy resin, an acrylic resin, a phenolic resin, a solvent, etc. are mixed, and each resin is dissolved in the solvent to prepare the resin composition. The viscosity of the composition can be adjusted by changing the amount of the solvent. It should be noted that commercially available products can be used as these resins.

[0205] In the chip bonding layer production process, for example, the resin composition prepared as above is applied to a release sheet. The coating method is not particularly limited, and a common coating method such as roller coating, screen coating, gravure coating, etc. can be used. Then, as needed, the applied composition is cured by desolventizing treatment, curing treatment, etc. to produce the chip bonding layer 10.

[0206] In the pasting process, the peeling sheets are peeled off from the adhesive layer 22 of the dicing tape 20 and the chip bonding layer 10, respectively, and the chip bonding layer 10 is directly contacted with the adhesive layer 22. For example, the bonding can be performed by crimping. The temperature during the pasting is not particularly limited, for example, it is 30°C or more and 50°C or less, preferably 35°C or more and 45°C or less. The linear pressure during the pasting is not particularly limited, preferably 0.1kgf / cm or more and 20kgf / cm or less, more preferably 1kgf / cm or more and 10kgf / cm or less.

[0207] The dicing die-bonding film 1 manufactured as described above is used as an auxiliary tool for manufacturing a semiconductor integrated circuit, for example. A specific example of its use will be described below.

[0208] The method of manufacturing a semiconductor integrated circuit generally includes a step of cutting chips from a semiconductor wafer having a circuit surface formed thereon and assembling the chips.

[0209] This process includes, for example, the following processes: a half-cutting process of forming grooves on the semiconductor wafer in order to process the semiconductor wafer into a die by cutting, and then grinding the semiconductor wafer to reduce the thickness; a mounting process of attaching one side (for example, the side opposite to the circuit surface) of the semiconductor wafer processed by half-cutting to the die bonding layer 10 and fixing the semiconductor wafer to the dicing tape 20; an expansion process of expanding the interval between the semiconductor chips processed by half-cutting; a pickup process of peeling the die bonding layer 10 and the adhesive layer 22 and taking out the semiconductor die in a state where the die bonding layer 10 is attached; and a die bonding process of attaching the semiconductor die in a state where the die bonding layer 10 is attached to the adherend. When implementing these processes, the dicing tape (dicing die bonding film) of this embodiment is used as a manufacturing auxiliary tool.

[0210] In the half-cutting process, Figure 2A to Figure 2D As shown in the figure, a half-cutting process for cutting a semiconductor integrated circuit into small pieces (die) is performed. In detail, a wafer processing tape T is attached to the surface of the semiconductor wafer W on the opposite side to the circuit surface. In addition, a cutting ring R is mounted on the wafer processing tape T. A dividing groove is formed in a state where the wafer processing tape T is attached. A back grinding tape G is attached to the surface where the groove is formed, and on the other hand, the wafer processing tape T attached initially is peeled off. A grinding process is performed in a state where the back grinding tape G is attached until the semiconductor wafer W reaches a specified thickness.

[0211] During the installation process, Figure 3A to Figure 3BAs shown, a dicing ring R is attached to the adhesive layer 22 of the dicing tape 20, and a semiconductor wafer W that has been half-cut is attached to the exposed surface of the die bonding layer 10. Thereafter, the back grinding tape G is peeled off from the semiconductor wafer W.

[0212] In the expansion process, Figure 4A to Figure 4C As shown, after installing the cutting ring R on the adhesive layer 22 of the cutting tape 20, it is fixed to the holding tool H of the expansion device. The lifting component U of the expansion device is lifted up from the lower side of the cutting chip bonding film 1, thereby stretching the cutting chip bonding film 1 and expanding it in the surface direction. Thereby, the semiconductor wafer W that has been half-cut is cut under specific temperature conditions. The above-mentioned temperature conditions are, for example, -20 to 0°C, preferably -15 to 0°C, and more preferably -10 to -5°C. The expansion state is released by lowering the lifting component U (it has been a low-temperature expansion process so far). Furthermore, in the expansion process, as Figure 5A to Figure 5B As shown in FIG. 1 , the dicing tape 20 is stretched under a higher temperature condition to expand the area. Thus, the adjacent semiconductor chips that have been cut are separated in the surface direction of the film surface, and the cut (interval) is further expanded (room temperature expansion step).

[0213] In the picking process, Figure 6 As shown, the semiconductor chip with the die bonding layer 10 attached thereto is peeled off from the adhesive layer 22 of the dicing tape 20. Specifically, the pin member P is raised to lift up the semiconductor chip to be picked up through the dicing tape 20. The lifted semiconductor chip is held by the suction jig J.

[0214] In the die bonding step, the semiconductor chip with the die bonding layer 10 attached thereto is bonded to an adherend.

[0215] As described above, the dicing die bonding film 1 (dicing tape 20) of the present embodiment is used in the above-mentioned process, and in the low-temperature expansion process, the dicing tape 20 is stretched at 0°C or below in a state where the wafer is bonded to the die bonding layer 10, and the wafer is cut together with the die bonding layer 10. Furthermore, in the expansion process at room temperature, the dicing tape 20 is stretched.

[0216] The temperature in the low-temperature extension step is usually 0° C. or lower, for example, −15° C. to 0° C. The temperature in the normal-temperature extension step is, for example, 10° C. to 25° C.

[0217] Matters disclosed by this specification include the following matters. (1)

[0219] A dicing tape comprising a base layer and an adhesive layer having higher adhesiveness than the base layer.

[0220] The volume crystallinity of the substrate layer calculated from the differential scanning calorimetry results was 20 J / cm 3 Above and 120J / cm 3 Below, and the thickness of the base material layer is 80 μm or more. (2)

[0222] The dicing tape according to the above (1), wherein a spectrum measured by differential scanning calorimetry of the base material layer has an endothermic peak, and a peak temperature of the endothermic peak is 100° C. or higher. (3)

[0224] The dicing tape according to the above (2), wherein the temperature difference between the peak start point (point A) and the top point (point C) in the endothermic peak is 40° C. or less. (4)

[0226] The dicing tape according to (2) or (3) above, wherein in the endothermic peak, a temperature difference between a peak start point (point A) and a peak end point (point B) is 30° C. or more and 60° C. or less. (5)

[0228] The dicing tape according to any one of (2) to (4) above, wherein in the endothermic peak, a temperature of a peak starting point (point A) is 70° C. or higher. (6)

[0230] The dicing tape according to any one of (2) to (5) above, wherein in the endothermic peak, a temperature at a peak end point (point B) is 150° C. or less. (7)

[0232] The dicing tape according to any one of (1) to (6) above, wherein the base layer has a single-layer structure or a laminated structure. (8)

[0234] The dicing tape according to any one of (1) to (7) above, wherein the base layer is composed of at least three layers. (9)

[0236] The cutting tape according to (8) above, wherein the base layer comprises a three-layer structure having two non-elastic layers (X, X) formed of a non-elastic body, and an elastic layer (Y) formed of an elastomer and arranged between the two non-elastic layers. (10)

[0238] The dicing tape according to (9) above, wherein the base layer has a three-layer structure, and a ratio of a thickness of an inner layer to a thickness of one outer layer (Y thickness / X thickness) is 5 or more and 15 or less. (11)

[0240] The dicing tape according to (9) or (10) above, wherein the non-elastic layer (X) includes at least one selected from the group consisting of low-density polyethylene (LDPE), high-density polyethylene (HDPE) and polypropylene. (12)

[0242] The dicing tape according to any one of (9) to (11) above, wherein the elastomer layer (Y) comprises an ethylene-vinyl acetate copolymer (EVA). (13)

[0244] The dicing tape according to any one of (1) to (11) above, wherein a ratio of a thickness of the adhesive layer to a total thickness of the dicing tape is 5% or more and 30% or less. (14)

[0246] A dicing die-bonding film comprising the dicing tape according to any one of (1) to (13) above and a die-bonding layer attached to the dicing tape. (15)

[0248] The dicing die-bonding film according to the above (14), wherein the die-bonding layer contains at least one of a thermosetting resin and a thermoplastic resin. (16)

[0250] The dicing die-bonding film according to (14) or (15) above, wherein the die-bonding layer has a thickness of 1 μm to 200 μm.

[0251] 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.

[0252] That is, various forms used for general dicing tapes and dicing die-bonding films can be adopted within a range that does not impair the effects of the present invention.

[0253] Example

[0254] Next, the present invention will be described in more detail using experimental examples, but the present invention is not limited to these.

[0255] The dicing tape was manufactured as follows: Furthermore, a dicing die-bonding film was manufactured using the dicing tape.

[0256] <Base material layer>

[0257] The products shown below were used as raw materials to produce a three-layer laminated base material layer or a single-layer base material layer.

[0258] Resin constituting the inner layer

[0259] Raw material name: Ultrathene 626

[0260] Ethylene-vinyl acetate copolymer resin (EVA contains 15% by mass of vinyl acetate)

[0261] Made by Tosoh Corporation

[0262] Resin constituting the inner layer

[0263] Raw material name: Ultrathene 633

[0264] Ethylene-vinyl acetate copolymer resin (EVA contains 20% by mass of vinyl acetate)

[0265] Made by Tosoh Corporation

[0266] Resin constituting the inner layer

[0267] Raw material name: Evaflex V523

[0268] Ethylene-vinyl acetate copolymer resin (EVA contains 33% by mass of vinyl acetate)

[0269] Made by DOW-MITSUI POLYCHEMICALS

[0270] Resin constituting the inner layer

[0271] Raw material name: Evaflex P1007

[0272] Ethylene-vinyl acetate copolymer resin (EVA contains 9% by mass of vinyl acetate)

[0273] Made by DOW-MITSUI POLYCHEMICALS

[0274] Resin constituting the base material layer of the comparative example

[0275] Raw material name: Infuse 9530

[0276] α-Olefin block copolymer resin

[0277] Made by Dow Chemical

[0278] Resin constituting the outer layer

[0279] Raw material name: WINTEC WFX4M

[0280] Metallocene Polypropylene

[0281] Made in Japan Polypropylene Co., Ltd.

[0282] (Formation of base material layer)

[0283] The substrate layer was formed using an extrusion T-die forming machine. The extrusion temperature was 190°C. For the three-layer laminated type substrate layer, co-extrusion molding was performed by a T-die to integrate it. After the integrated substrate layer (laminated body) was fully cured, the substrate layer was rolled into a roll for storage.

[0284] In addition, the thickness ratio of each layer which comprises a base material layer and the total thickness of a base material layer are as shown in Table 1.

[0285] <Adhesive Layer>

[0286] (Preparation of Adhesive Layer (Adhesive Composition))

[0287] The following raw materials were mixed to prepare a first resin composition.

[0288] INA (isononyl acrylate) 173 parts by mass

[0289] HEA (hydroxyethyl acrylate) 54.5 parts by mass

[0290] ·AIBN (2,2'-azobisisobutyronitrile) 0.46 parts by mass

[0291] · 372 parts by mass of ethyl acetate

[0292] Next, the first resin composition was added to a round-bottom separable flask of a polymerization experimental device equipped with a round-bottom separable flask (capacity 1 L), a thermometer, a nitrogen inlet tube and a stirring blade. While stirring the first resin composition, the liquid temperature of the first resin composition was adjusted to room temperature (23° C.), and the inside of the round-bottom separable flask was replaced with nitrogen for 6 hours.

[0293] Next, while nitrogen was flowed into the round-bottom separable flask, the first resin composition was kept at a liquid temperature of 62° C. for 3 hours while being stirred. Thereafter, the polymerization reaction of INA, HEA and AIBN was further carried out by keeping the temperature at 75° C. for 2 hours to prepare a second resin composition. Thereafter, the flow of nitrogen into the round-bottom separable flask was stopped.

[0294] After the second resin composition was cooled to room temperature, the following raw materials were added to the second resin composition.

[0295] ·2-Methacryloyloxyethyl isocyanate

[0296] Compounds with polymerizable carbon-carbon double bonds

[0297] Trade name "KARENZ MOI", manufactured by Showa Denko K.K.) 52.5 parts by mass

[0298] · Dibutyltin dilaurate IV (manufactured by Wako Pure Chemical Industries, Ltd.) 0.26 parts by mass

[0299] The obtained third resin composition was stirred at 50° C. for 24 hours in an air atmosphere.

[0300] Finally, the following raw materials were added to 100 parts by mass of the polymer solid content of the third resin composition.

[0301] Isocyanate compound (trade name "COLONATE L", manufactured by Tosoh Corporation) 0.75 parts by mass

[0302] · Photopolymerization initiator (trade name "Omnirad 127", manufactured by IGM Resins Co., Ltd.) 2 parts by mass

[0303] Then, the third resin composition was diluted with ethyl acetate so as to have a solid content concentration of 20% by mass, thereby preparing an adhesive composition.

[0304] <Manufacturing of Cutting Tape>

[0305] The adhesive composition was applied to one surface of the base layer using an applicator so that the thickness after drying was 10 μm. The base layer after the adhesive composition was applied was heated and dried at 110° C. for 3 minutes to form an adhesive layer, thereby manufacturing a dicing tape.

[0306] <Production of Dicing Die Bonding Film>

[0307] (Fabrication of chip bonding layer)

[0308] The following raw materials were added to methyl ethyl ketone and mixed to obtain a die bond layer composition having a solid content concentration of 20% by mass.

[0309] · Acrylic resin (trade name "SG-P3", manufactured by Nagase Chemtex Co., Ltd., glass transition temperature: 12° C.) 100 parts by mass

[0310] Epoxy resin (trade name "JER1001", manufactured by Mitsubishi Chemical Corporation) 46 parts by mass

[0311] Phenolic resin (trade name "MEH-7851ss", manufactured by Meiwa Chemicals Co., Ltd.) 51 parts by mass

[0312] Spherical silica (trade name "SO-25R", manufactured by ADMATECHS) 191 parts by mass

[0313] Curing catalyst (trade name "CUREZOL PHZ", manufactured by Shikoku Chemical Industry Co., Ltd.) 0.6 parts by mass

[0314] Next, a release liner prepared by applying silicone treatment to a PET-based release film (50 μm thick) was prepared. The chip bonding layer composition was applied to the treated surface of the release liner using an applicator so that the thickness after drying was 10 μm. The solvent was evaporated from the chip bonding layer composition by drying at 130° C. for 2 minutes to obtain a chip bonding sheet having a chip bonding layer laminated on the release liner.

[0315] (Attachment of chip bonding layer and dicing tape)

[0316] Next, the adhesive layer of the dicing tape is attached to the die bonding layer (the side without the release sheet) of the die bonding sheet. Thereafter, the release liner is peeled off from the die bonding layer to prepare a dicing die bonding film having a die bonding layer.

[0317] As described above, dicing tapes and dicing die-bonding films of Examples and Comparative Examples were manufactured according to the above-mentioned methods. The structures of the dicing tapes are shown in Table 1.

[0318] [Table 1]

[0319]

[0320] The calculation method of volume crystallinity is as follows. The volume crystallinity corresponding to the inner layer is calculated by multiplying the heat absorption of the inner layer by the thickness ratio of the inner layer and then multiplying it by the specific gravity of the inner layer. The volume crystallinity is calculated for the outer layer in the same way. And, these calculated values ​​are added together. The total value is used as the volume crystallinity.

[0321] <Measurement by Differential Scanning Calorimetry (DSC)>

[0322] The measurement sample was taken out from the diced tape of each Example and each Comparative Example. The measurement sample was taken out from the base material layer by dicing the base material layer in the thickness direction.

[0323] Using a commercially available DSC measuring apparatus, about 10 mg of a sample for measurement was weighed, and the temperature was raised from room temperature (about 20° C.) to 200° C. at a heating rate of 5° C. / min, and the measurement was performed in a nitrogen atmosphere.

[0324] The area of ​​the endothermic peak appearing in the spectrum, and the temperatures of the peak start point, peak apex, and peak end point of the endothermic peak were measured using analysis software attached to the device.

[0325] When a plurality of peaks appear in the measurement spectrum, the above-mentioned temperatures and the like are measured for each peak.

[0326] The details of the DSC measurement apparatus and analysis software are shown below.

[0327] Measuring device: TA Instruments Japan

[0328] Device NameDSC Q-2000

[0329] Analysis software: TA Instruments Universal Analysis 2000 version 4.5A

[0330] The spectrum when differential scanning calorimetry (DSC measurement) was performed on the substrate layer of Example 1 is shown in FIG. Fig. 7A and Figure 7B . Fig. 7A and Figure 7B Use different forms of expression to express the same measurement results. Fig. 7A The oblique line in the spectrum represents the temperature.

[0331] Similarly, the spectrum of the substrate layer of Comparative Example 1 when subjected to differential scanning calorimetry (DSC measurement) is shown in FIG. Fig. 8A and Figure 8B .

[0332] <Performance Evaluation (Evaluation of Cutting Properties)>

[0333] Using the dicing die-bonding films produced in each of the Examples and Comparative Examples, performance evaluation was performed as follows.

[0334] After a wafer processing tape (trade name "V-12SR2", manufactured by Nitto Denko Corporation) was attached to one side of a bare wafer (diameter 300 mm), the bare wafer was fixed to a dicing ring with the wafer processing tape, and a dicing device (manufactured by DISCO Corporation, model 6361) was used to form a grid-shaped groove (25 μm wide, 100 μm deep) from the side opposite to the side on which the wafer processing tape was attached, so that the chip became a 2 mm × 2 mm square. Next, the wafer processing tape (trade name "V-12SR2", manufactured by Nitto Denko Corporation) was peeled off from the wafer, and a back grinding tape was attached to the surface on which the grooves were formed, and a back grinding machine (manufactured by DISCO Corporation, model DGP8760) was used to grind the bare wafer to a thickness of 30 μm (0.030 mm).

[0335] A ground wafer with a back grinding tape is pasted on the chip bonding film surface of the dicing chip bonding tape at a temperature of 60°C. Next, the dicing chip bonding film pasted to the ground wafer is pasted to a ring and fixed, and then the back grinding tape is peeled off. Thereafter, the chip bonding layer is cut using a cold expansion unit at an expansion temperature of -5°C, an expansion speed of 100mm / second, and an expansion amount of 14mm. Next, normal temperature expansion is performed at room temperature, an expansion speed of 1mm / second, and an expansion amount of 10mm. Furthermore, while maintaining the expansion state, the periphery of the dicing chip bonding film is thermally shrunk at a heating temperature of 200°C, a heating distance of 18mm, and a rotation speed of 5° / second.

[0336] In the diced chip bonding film after heat shrinkage, the cutting of the chip bonding layer was confirmed using a microscope, and the case where the cutting rate was 90% or more was recorded as 0, the case where it was less than 90% and 80% or more was recorded as △, and the case where it was less than 80% was recorded as ×.

[0337] Table 1 shows the results of differential scanning calorimetry (DSC) and performance evaluation (evaluation of splitting properties) performed on the base material layer of the dicing tape of each Example and each Comparative Example.

[0338] From the above evaluation results, it can be understood that the dicing die-bonding film of the example can better divide the semiconductor wafer in the low-temperature expansion step than the dicing die-bonding film of the comparative example.

[0339] In the dicing tape of the example, the volume crystallinity of the base layer calculated from the DSC measurement spectrum was 20 J / cm 3 Above and 120J / cm 3 Below, and the thickness of the base material layer is 80 μm or more.

[0340] Since the above volume crystallinity is 20 J / cm 3 As a result, the crystallinity of the substrate layer is relatively large, so the semiconductor wafer can be well cut in the low temperature expansion process. In addition, since the volume crystallinity is 120 J / cm 3 Therefore, the crystallinity of the base material layer does not increase more than necessary, and thus the base material layer 21 can be suppressed from being cracked during expansion.

[0341] By using the dicing tape (dicing die-bonding film) of the embodiment including the base material layer having such physical properties in the manufacture of semiconductor integrated circuits, cracking of the base material layer 21 can be suppressed and the semiconductor wafer can be well divided in the low-temperature expansion process.

[0342] Industrial Applicability

[0343] The dicing tape and dicing die-bonding film of the present invention can be suitably used as an auxiliary tool in manufacturing a semiconductor integrated circuit, for example.

Claims

1. A dicing tape comprising a substrate layer and an adhesive layer having higher adhesiveness than the substrate layer, The base material layer includes two non-elastic layers formed of a non-elastic body and an elastic layer disposed between the two non-elastic layers and formed of an elastomer. The ratio of the thickness of the elastic layer to the thickness of one non-elastic layer is 5 or more and 15 or less, The two non-elastomeric layers respectively contain metallocene polypropylene, The elastomer layer contains an ethylene-vinyl acetate copolymer, wherein the ethylene-vinyl acetate copolymer contains 5% by mass or more and 35% by mass or less of a vinyl acetate structural unit. The volume crystallinity of the substrate layer, which is obtained by calculating the endothermic amount from the area of ​​the endothermic peak appearing in the spectrum obtained by differential scanning calorimetry and converting the calculated endothermic amount into a value per unit volume, is 20 J / cm 3 Above and 120J / cm 3 In addition, the thickness of the base material layer is 80 μm or more and 150 μm or less.

2. The cutting tape according to claim 1, wherein: The top temperature of the endothermic peak is 100° C. or higher. 3 . A dicing die-bonding film comprising the dicing tape according to claim 1 or 2 and a die-bonding layer attached to the dicing tape.

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