Base film for dicing tape and dicing tape

Abstract

The present invention provides a substrate film for a dicing tape and a dicing tape that can take into account both suppressing the generation of cutting chips in the dicing process and improving the pick-up property in the pick-up process. The substrate film of the present invention is a substrate film for a dicing tape, having a first surface on which an adhesive layer is formed and a second surface opposite thereto, and is composed of a resin containing a thermoplastic polyester elastomer, wherein the thermoplastic polyester elastomer is a block copolymer containing a hard segment (A) and a soft segment (B), wherein the hard segment (A) has a polyester composed of an aromatic dicarboxylic acid and an aliphatic diol or an alicyclic diol as a main component, and the soft segment (B) has an aliphatic polyether as a main component, and the substrate film has a bending elastic modulus (G') at 23°C in the range of 10 MPa to 135 MPa when the dynamic viscoelasticity is measured using a clamped-end beam bending mode at a frequency of 1 Hz and a heating rate of 0.5°C / min.

Description

Technical Field

[0001] The present invention relates to a base film for a dicing tape for fixing a semiconductor wafer when dicing the semiconductor wafer into chip-shaped elements, and a dicing tape using the base film. Background Art

[0002] In the past, in the manufacture of semiconductor devices, in order to singulate a semiconductor wafer into semiconductor chips through a dicing (hereinafter sometimes referred to as "cutting" or "cutting") process, a dicing tape or a dicing chip pasting film formed by integrating the dicing tape with a chip pasting film was sometimes used. The dicing tape is provided with an adhesive layer on a base film, and is used to arrange the semiconductor wafer on the adhesive layer, and to fix and hold the singulated semiconductor chips when the semiconductor wafer is cut to prevent them from flying. Then, the semiconductor chip is peeled off from the adhesive layer of the dicing tape, and fixed to an adherend such as a lead frame or a wiring substrate by an adhesive or adhesive film prepared separately.

[0003] The die-bonding film for dicing is a material having a die-bonding film (hereinafter sometimes referred to as "adhesive film" or "adhesive layer") removably provided on the adhesive layer of the dicing tape. In the manufacture of semiconductor devices, the semiconductor wafer is held on the die-bonding film of the die-bonding film for dicing, and the semiconductor wafer is diced together with the die-bonding film to obtain individual semiconductor chips with adhesive films. Then, the semiconductor chip is peeled off from the adhesive layer of the dicing tape together with the die-bonding film as a semiconductor chip with a die-bonding film, and the semiconductor chip is fixed to an adherend such as a lead frame or a wiring substrate through the die-bonding film.

[0004] After obtaining the semiconductor chip or the semiconductor chip with the die-attaching film as described above, the semiconductor wafer in the state of being held on the adhesive layer of the dicing tape and the die-attaching film surface of the dicing die-attaching film is sometimes subjected to blade dicing. In the blade dicing, the semiconductor wafer or the semiconductor wafer and the die-attaching film of the dicing die-attaching film holding it are cut by a dicing blade rotating at a high speed, thereby singulating into semiconductor chips or semiconductor chips with adhesive films of a predetermined size. In the blade dicing process, in order to remove the cutting chips that are inevitably generated, the cutting process is performed while supplying running water to the dicing blade and the semiconductor wafer.

[0005] In such a blade cutting process, in order to accurately obtain semiconductor chips or semiconductor chips with adhesive films from large-diameter semiconductor wafer workpieces, it is preferred to completely cut and divide them in a so-called full-cut method. However, in fact, considering the movement accuracy of the device, the thickness accuracy of the dicing tape, chip adhesive film and semiconductor wafer used, the cutting depth of the dicing knife that cuts into the semiconductor wafer from the side opposite to the dicing tape sometimes reaches the substrate film of the dicing tape. In this case, wire-like cuttings are sometimes generated during cutting. In this regard, it is believed that friction heat is generated in the substrate at the part in contact with the high-speed rotating dicing knife, and the substrate constituent material softened and melted by the friction heat is stretched due to the tensile effect from the high-speed rotating dicing knife, thereby generating wire-like cuttings.

[0006] Most of these filament-like cuttings will continue to adhere to the semiconductor chip that has undergone the blade cutting process under running water supply. If the filament-like cuttings continue to adhere to the semiconductor chip, the following problems will arise: the reliability of the semiconductor element will be reduced, the semiconductor chip cannot be accurately picked up due to recognition errors during the picking process, the semiconductor chip will be broken and cannot be picked up, or the picked semiconductor chip cannot be correctly oriented and installed with high precision. Therefore, in the blade cutting process, it is expected that the amount of such filament-like cuttings generated will be smaller.

[0007] As a prior art for suppressing the generation of cutting chips, Reference 1 discloses an adhesive tape for fixing semiconductor wafers for the purpose of providing a cutting adhesive tape that can prevent cutting chips from remaining on the surface of the semiconductor wafer in a full-cut cutting method, characterized in that it is formed by laminating a resin layer and an adhesive layer, the resin layer having an MFR (melt mass flow rate) of 3 or less at a test temperature of 190° C., and containing a constituent component having a carboxyl group as a constituent component of the polymer. In addition, Reference 2 discloses a cutting base film having a layer containing a resin containing aromatic polyamide for the purpose of providing a cutting base film and a cutting film that hardly generate cutting chips in the cutting process of semiconductor wafers, etc.

[0008] On the other hand, in recent years, with the popularization of IC cards and the rapid increase in the capacity of USB memory, the number of overlapping semiconductor chips has increased, and it is expected that semiconductor chips will be further thinned. For this reason, it is necessary to reduce the thickness of semiconductor chips from the previous thickness of 200 to 350 μm to a thickness of 50 to 100 μm or less. In addition, in order to achieve further cost reduction, it is strongly required to produce semiconductor chips with high productivity and high yield as much as possible, and the maximum efficiency is also required in each process of the semiconductor device manufacturing process.

[0009] However, silicon, glass, etc. used as semiconductor chips are brittle materials. If the thickness of the semiconductor chip is reduced as described above, the risk of damage during transportation and processing will become higher. For example, as one of the manufacturing processes of semiconductor devices, there is a process of picking up single-chip semiconductor chips or semiconductor chips with adhesive films. However, if the thickness of the semiconductor chip is reduced, the semiconductor chip is easy to break when picking up. In the picking up process, the mainstream method is to push up the cut semiconductor chip or semiconductor chip with adhesive film from the substrate film side of the dicing tape using a push pin (needle-shaped object) to help the semiconductor chip or semiconductor chip with adhesive film be peeled off from the adhesive layer, while using an adsorption barrel clamp to adsorb the semiconductor chip or semiconductor chip with adhesive film from above, thereby picking it up from the adhesive layer of the dicing tape. In this case, it is considered that if it is difficult to help the semiconductor chip or the semiconductor chip with an adhesive film to be peeled off from the adhesive layer when pushing up the semiconductor chip or the semiconductor chip with an adhesive film, it is necessary to further increase the pushing height (pushing amount) to promote the peeling. As a result, the stress on the semiconductor chip becomes greater and the warping of the semiconductor chip increases, thereby causing cracks.

[0010] Therefore, the current situation is that the following methods are adopted to deal with it, for example, the pushing speed of the push pin (needle-shaped object) is reduced or adjusted to an appropriate speed, and on this basis, the thin film semiconductor chip is carefully picked up while adjusting the pushing height. However, it is still not considered that the reduction in yield caused by the breakage of semiconductor chips in the picking process has been fully solved, and since it depends largely on the type of dicing tape, it is urgently desired to further improve the dicing tape together with the picking mechanism. Specifically, a dicing tape that can pick up thin film semiconductor chips without damage at a pushing speed within the allowable range in actual use and a smaller pushing height is desired.

[0011] As a prior art for improving the pick-up property, Reference 3 discloses a dicing tape having an adhesive layer on a substrate film having a ring stiffness of 3 to 25 mN measured under predetermined conditions, with the purpose of providing a dicing tape capable of efficiently picking up thin semiconductor chips in a picking-up process after a dicing process. In addition, Reference 4 discloses a film formed of a polyester block copolymer composed of a combination of a specific hard segment component and a soft segment component, with the purpose of providing an antistatic film used in semiconductor device manufacturing having both good expansion characteristics and pick-up properties.

[0012] Prior art literature

[0013] Patent Literature

[0014] Patent Document 1: Japanese Patent Application Laid-Open No. 9-8111

[0015] Patent Document 2: Japanese Patent Application Publication No. 2016-31996

[0016] Patent Document 3: Japanese Patent Application Publication No. 2010-225753

[0017] Patent Document 4: Japanese Patent Application Publication No. 2006-152072 Summary of the invention

[0018] Problems to be solved by the invention

[0019] Regarding the adhesive tape for fixing semiconductor wafers of Reference 1, the generation of cutting chips in the dicing process is indeed suppressed by using a resin with high melt viscosity for the base film, but the pickup characteristics of the thin film semiconductor chip are not particularly mentioned. The ethylene-methacrylic acid copolymer and ethylene-methacrylic acid-(2-methylpropyl acrylate) terpolymer resins exemplified as the material of the base film in the embodiment have high melt viscosity and are therefore slightly hard materials. When the semiconductor chip is thin, the pickup characteristics may be insufficient.

[0020] In addition, the dicing film of Reference 2 does suppress the generation of cutting chips in the dicing process, but does not specifically mention the pickup characteristics of the thin film semiconductor chip. The aromatic polyamide as the main component of the material of the base film exemplified in the embodiment is a hard material with a high melting point, so when the semiconductor chip is thin, the pickup characteristics may be insufficient.

[0021] On the other hand, for the dicing tape of Reference 3, it can be considered that the pick-up property of the semiconductor chip with a thickness of 100 μm in the embodiment has a certain improvement effect, but there is still room for improvement (reduction) in the push-up height (pin height) during pick-up. Although there is no special mention of suppressing the generation of cutting chips in the dicing process, the resins such as ethylene-vinyl acetate and ethylene-methacrylic acid copolymer with a large MFR, which are exemplified as the material of the base film in the embodiment, have a slightly low melting point and may not be sufficient to suppress the generation of cutting chips in the dicing process.

[0022] Furthermore, for the semiconductor wafer fixing film of Reference 4, it is believed that the pick-up property of the semiconductor chip with a thickness of 350 μm in the embodiment is good, but the pick-up property when applied to the semiconductor chip with a thickness of less than 100 μm and its specific content are unknown. In addition, there is no special mention of suppressing the generation of cutting chips in the dicing process.

[0023] Thus, when the conventional dicing tape is applied to semiconductor wafers having a thickness of 100 μm or less, it is difficult to say that it is fully satisfactory from the viewpoint of both suppressing the generation of cutting chips in the dicing process and improving the pickup performance in the pickup process, and there is still room for improvement.

[0024] The present invention has been completed in view of the above-mentioned problems and circumstances, and its purpose is to provide a base film for a dicing tape that can suppress the generation of cutting chips in the cutting process and improve the picking-up performance in the picking-up process within a range that does not cause problems in practical use, even when applied to semiconductor wafers with a thickness of less than 100 μm, and to provide a dicing tape using the base film.

[0025] Methods for solving problems

[0026] That is, the present invention provides a substrate film, which is a substrate film for a dicing tape, having a first surface on which an adhesive layer is formed and a second surface opposite thereto,

[0027] The invention is composed of a resin containing a thermoplastic polyester elastomer, wherein the thermoplastic polyester elastomer is a block copolymer containing a hard segment (A) and a soft segment (B), wherein the hard segment (A) contains a polyester composed of an aromatic dicarboxylic acid and an aliphatic diol or an alicyclic diol as a main component, and the soft segment (B) contains an aliphatic polyether as a main component, characterized in that:

[0028] The base film has a flexural modulus (G') at 23° C. in the range of 10 MPa to 135 MPa, when dynamic viscoelasticity is measured using a clamped-end-beam flexural mode at a frequency of 1 Hz and a heating rate of 0.5° C. / min.

[0029] In one embodiment, the base film has a bending modulus (G') at 23° C. in a range of 17 MPa to 115 MPa.

[0030] In one embodiment, the soft segment (B) has a content (copolymerization amount) in the range of 51% by mass or more and 73% by mass or less relative to the total mass of the hard segment (A) and the soft segment (B).

[0031] In one embodiment, the soft segment (B) has a content (copolymerization amount) in the range of 55 mass % or more and 70 mass % or less with respect to the total mass of the hard segment (A) and the soft segment (B).

[0032] In one embodiment, the hard segment (A) is polybutylene terephthalate (PBT).

[0033] In one embodiment, the soft segment (B) is poly(oxytetramethylene) glycol (PTMG) and / or ethylene oxide addition polymer of poly(propylene oxide) glycol (PPG-EO addition polymer).

[0034] In one embodiment, the substrate film is composed of a single resin layer, and the resin containing the thermoplastic polyester elastomer constituting the layer has a crystalline melting point in the range of 160° C. to 200° C.

[0035] In one embodiment, the base film is composed of a plurality of laminated resin layers, and the resin containing the thermoplastic polyester elastomer constituting the layer having the first surface has a crystalline melting point in the range of 160° C. to 200° C.

[0036] In one embodiment, the base film has a thickness in a range of 70 μm to 155 μm.

[0037] In one embodiment, the elongation of the base film is in the range of 300% to 700%.

[0038] Furthermore, the present invention provides a dicing tape comprising any one of the aforementioned base films and an adhesive layer formed on the surface thereof.

[0039] Effects of the Invention

[0040] According to the present invention, a base film for a dicing tape can be provided that can simultaneously suppress the generation of cutting chips in the dicing process and improve the pick-up performance in the pick-up process within a range that does not cause problems in practical use, even when applied to a semiconductor wafer having a thickness of 100 μm or less. In addition, a dicing tape using the base film can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] [ Figure 1 ] (a) to (d) are cross-sectional views showing an example of the structure of a base film for a dicing tape applied to the present embodiment.

[0042] [ Figure 2 ] is a cross-sectional view showing an example of the structure of a dicing tape using a base film for a dicing tape applied in the present embodiment.

[0043] [ Figure 3 ] is a cross-sectional view showing an example of a structure in which a dicing tape using a base film for a dicing tape applied to the present embodiment is bonded to a chip pasting film.

[0044] [ Figure 4 ] is a flow chart illustrating a method for manufacturing a cutting tape.

[0045] [ Figure 5 ] is a flowchart illustrating a method for manufacturing a semiconductor chip.

[0046] [ Figure 6 ] is a three-dimensional diagram showing a state in which a ring frame (wafer ring) is attached to the outer edge of a dicing tape (or a chip pasting film for dicing) and a semiconductor wafer is attached to the center.

[0047] [ Figure 7 ](a) to (f) are cross-sectional views showing an example of manufacturing a semiconductor chip using a dicing tape.

[0048] [ Figure 8 ] (a) to (f) are cross-sectional views showing an example of manufacturing a semiconductor chip using a dicing die attach film.

[0049] Explanation of symbols

[0050] 1 ... base film, 2 ... adhesive layer, 3 ... die attach film (adhesive layer), 10 ... dicing tape, 20 ... dicing die attach film, 30 ... semiconductor wafer, 30a ... semiconductor chip, 40 ... ring frame, 50 ... suction collet, 60 ... push pin (needle-shaped object) DETAILED DESCRIPTION

[0051] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. However, the present invention is not limited to the following embodiments.

[0052] 《Constitution of base film and dicing tape》

[0053] Figure 1 (a) to (d) are cross-sectional views showing an example of the structure of the base film 1 for dicing tape used in this embodiment. The base film 1 of this embodiment may be a single layer of a single resin (see Figure 1 (a) 1-A), it may also be a laminate composed of multiple layers of the same resin (see Figure 1 (b) 1-B), it may also be a laminate composed of multiple layers of different resins (see Figure 1 (c) 1-C, (d) 1-D). When a laminate composed of multiple layers is formed, the number of layers is not particularly limited, but is preferably in the range of 2 to 5 layers.

[0054] Figure 2 1 is a cross-sectional view showing an example of the structure of a dicing tape using the base film 1 for dicing tape applied to the present embodiment. Figure 2 As shown, the dicing tape 10 has a structure in which an adhesive layer 2 is provided on the first surface of a base film 1. It should be noted that, although not shown in the figure, a base sheet (release liner) having a release property may be provided on the surface of the adhesive layer 2 of the dicing tape 10 (the surface opposite to the surface facing the base film 1). As the adhesive forming the adhesive layer 2, for example, an active energy ray-curable acrylic adhesive that is cured and shrunk by irradiation with active energy rays such as ultraviolet rays (UV) and thus reduces the adhesive strength to the adherend can be used.

[0055] In the semiconductor manufacturing process, it is used as follows. A semiconductor wafer is held (temporarily fixed) on the adhesive layer 2 of the dicing tape 10, and after the semiconductor wafer is diced (cut) to produce individual semiconductor chips, the semiconductor chips are peeled off from the adhesive layer 2 of the dicing tape 10. The obtained semiconductor chips are fixed to an adherend such as a lead frame or a wiring substrate via an adhesive prepared separately.

[0056] Figure 3 This is a cross-sectional view showing an example of a so-called dicing die attach film in which a dicing tape 10 using a base film 1 for dicing tape applied in this embodiment is bonded and integrated with a die attach film (adhesive layer) 3. Figure 3 As shown, the dicing die attach film 20 has a structure in which a die attach film (adhesive layer) 3 is closely adhered and laminated on the adhesive layer 2 of the dicing tape 10 in a releasable manner.

[0057] In the semiconductor manufacturing process, it is used as follows. A semiconductor wafer is held (bonded) on the chip pasting film 3 of the dicing chip pasting film 20, and after the semiconductor wafer is cut into individual semiconductor chips, the semiconductor chip is peeled off from the adhesive layer 2 of the dicing tape 10 together with the chip pasting film (adhesive layer) 3. The obtained semiconductor chip with the chip pasting film (adhesive layer) 3 is fixed to an adherend such as a lead frame or a wiring substrate via the chip pasting film (adhesive layer) 3. It should be noted that, although not shown in the figure, the surface of the adhesive layer 2 of the dicing tape 10 (the surface on the opposite side to the surface facing the substrate film 1) and the surface of the chip pasting film 3 (the surface on the opposite side to the surface facing the adhesive layer 2) can each have a substrate sheet (peel-off liner) with a release property.

[0058] 《Base film》

[0059] The substrate film 1 of the present embodiment is composed of a resin containing a thermoplastic polyester elastomer. The thermoplastic polyester elastomer preferably contains 80% by mass or more, more preferably 90% by mass or more, of the total amount of the resin constituting the substrate film 1. First, the thermoplastic polyester elastomer as the main component of the resin constituting the substrate film 1 is described below.

[0060] <Thermoplastic polyester elastomer>

[0061] The thermoplastic polyester elastomer is a block copolymer having a hard segment (A) and a soft segment (B) as constituent components of the copolymer, i.e., a polyester-polyether type thermoplastic elastomer, wherein the hard segment (A) has a polyester composed of an aromatic dicarboxylic acid and an aliphatic diol or an alicyclic diol as a main component, and the soft segment (B) has an aliphatic polyether as a main component. Here, "having ~ as a main component" means that the "polyester composed of an aromatic dicarboxylic acid and an aliphatic diol or an alicyclic diol" accounts for 75% by mass or more, preferably 80% by mass or more, and particularly preferably 90% by mass or more of the total amount of the hard segment (A). Similarly, the "aliphatic polyether" accounts for 75% by mass or more, preferably 80% by mass or more, and particularly preferably 90% by mass or more of the total amount of the soft segment (B).

[0062] As described above, as one of the preferred characteristics for suppressing the generation of filament-like cutting chips during cutting, the high melting point of the substrate film 1 can be cited. On the other hand, as one of the preferred characteristics for improving the pickup of thin-film semiconductor chips, the softness of the substrate film 1 can be cited. However, these two characteristics are generally in a trade-off relationship in most cases. That is, if you want to increase the melting point of the substrate film 1, the softness will be lost, and if you want to give the substrate film 1 softness, the melting point tends to be lower. As a material that can eliminate such an opposing trade-off relationship, the above-mentioned thermoplastic polyester elastomer with both high melting point and softness is suitable. In particular, it is suitable as a material for the substrate film 1 from the aspect that both characteristics can be expressed in a single layer even without relying on a method of controlling the melting point and softness by laminating a layer with a high melting point and a layer with excellent softness as the composition of the substrate film 1.

[0063] (Hard segment (A))

[0064] The hard segment (A) of the thermoplastic polyester elastomer is set as a polyester composed of an aromatic dicarboxylic acid and an aliphatic diol or an alicyclic diol as the main component as described above. The aromatic polyester thus constituted is crystalline and has a high melting point. The hard domain formed by the crystalline polyester (hard segment) substantially acts as a crosslinking point by providing a node to the rubber-like soft segment described later. Thus, when the thermoplastic polyester elastomer is used as the material of the substrate film 1 of the cutting tape 10, it is not easy to melt during cutting, and even if it melts, the crystallization rate is fast, so it is not easy to become filamentous, thereby suppressing the generation of filamentous cutting chips.

[0065] There is no particular limitation on the aromatic dicarboxylic acid constituting the polyester as the main component of the hard segment (A), and a common aromatic dicarboxylic acid can be used. As aromatic dicarboxylic acids, specific examples include terephthalic acid, isophthalic acid, 5-sodium sulfoisophthalate, 2,6-naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, etc. Among them, as aromatic dicarboxylic acids, terephthalic acid or 2,6-naphthalene dicarboxylic acid, etc. are preferably used. From the viewpoint of ultraviolet transmittance, terephthalic acid is preferably used. The amount of these aromatic dicarboxylic acids used is preferably 75% by mass or more of the total acid component including other acid components, more preferably 80% by mass or more, and particularly preferably 90% by mass or more. In addition, the ester-forming derivatives of these aromatic carboxylic acids can also be used to replace the above-mentioned aromatic dicarboxylic acids, thereby being introduced into the above-mentioned polyester as an acid component. For example, representative is the alkyl ester of such an acid, and methyl ester is particularly preferably used. Specifically, methyl terephthalate is preferably used.

[0066] As the above-mentioned other acid components, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid and tetrahydrophthalic anhydride; aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, hydrogenated dimer acid, etc. can be cited. Other acid components are used within a range that does not significantly reduce the crystalline melting point of the thermoplastic polyester elastomer, and the amount used is preferably 25% by mass or less of the total acid components, more preferably 20% by mass or less, and particularly preferably 10% by mass or less. In addition, ester-forming derivatives of these acids can also be used in the same manner as above.

[0067] In addition, there is no particular limitation on the aliphatic or alicyclic diol constituting the polyester as the main component of the hard segment (A), and conventional aliphatic or alicyclic diols can be used. As aliphatic diols, for example, alkylene glycols having 2 to 8 carbon atoms can be cited, and specifically, ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc. can be used. As alicyclic diols, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, etc. can be used. Among them, 1,4-butanediol or 1,4-cyclohexanedimethanol is preferably used. From the viewpoint of versatility and film-forming properties, 1,4-butanediol as an aliphatic diol is preferably used.

[0068] The components constituting the polyester as the main component of the hard segment (A) are preferably polyesters composed of butylene terephthalate units formed from terephthalic acid and 1,4-butanediol (sometimes also referred to as polybutylene terephthalate (PBT)), or polyesters composed of butylene naphthalate units formed from 2,6-naphthalene dicarboxylic acid and 1,4-butanediol (sometimes also referred to as polybutylene naphthalate (PBN)) from the viewpoint of physical properties, moldability, and cost-effectiveness. In particular, polyesters composed of butylene terephthalate units (PBT) are preferred from the viewpoint of ultraviolet transmittance.

[0069] In addition, when an aromatic polyester suitable as a polyester constituting the hard segment (A) in the thermoplastic polyester elastomer of the present invention is prepared in advance and then copolymerized with the soft segment (B) component, the aromatic polyester can be obtained by a conventional polyester production method. In addition, the number average molecular weight Mn of the aromatic polyester is preferably in the range of 10,000 to 40,000.

[0070] (Soft segment (B))

[0071] As described above, the soft segment (B) of the thermoplastic polyester elastomer is mainly composed of an aliphatic polyether. The aliphatic polyether has a low glass transition temperature (Tg) and is rubbery, and controls the balance with the hard segment (A) to impart appropriate softness to the thermoplastic polyester elastomer. Thus, when the thermoplastic polyester elastomer is used as the material of the base film 1 of the dicing tape 10, the bending modulus (G') of the base film 1 at 23°C can be controlled within a range that can maximize the pickup of the thin film semiconductor chip, that is, within a range of 10 MPa to 135 MPa. If the bending elastic modulus (G') of the above-mentioned base film 1 at 23°C is in the range of 10 MPa to 135 MPa, when picking up the semiconductor chip, when the cutting tape 10 is pushed up by the push pin, the cutting tape 10 is easy to bend with the top of the pin as a fulcrum. Therefore, even if the push pin is pushed up with a small height, that is, it is pushed up with a small force, it is easy to help the four edges of the semiconductor chip to be peeled off from the adhesive layer 2.

[0072] As a result, even when using a semiconductor wafer with a thin film of less than 100 μm, the thin film semiconductor chip can be quickly peeled off from the adhesive layer 2, and the thin film semiconductor chip can be easily picked up from the adhesive layer 2 of the cutting tape 10 without damage using a smaller force than before, which can further improve the success rate of picking up the semiconductor chip compared with the past.

[0073] The aliphatic polyether as the main component of the soft segment (B) is not particularly limited, and specific examples thereof include poly(ethylene oxide) glycol, poly(propylene oxide) glycol, poly(oxytetramethylene) glycol, poly(oxyhexamethylene) glycol, copolymers of ethylene oxide and propylene oxide, ethylene oxide addition polymers of poly(propylene oxide) glycol, copolymers of ethylene oxide and tetrahydrofuran, and the like.

[0074] Among the above-mentioned aliphatic polyethers, poly(oxytetramethylene) glycol (PTMG), ethylene oxide addition polymers of poly(propylene oxide) glycol (PPG-EO addition polymers), and copolymer diols of ethylene oxide and tetrahydrofuran (EO / THF copolymer diols) are preferred. From the viewpoint of versatility and film forming properties, poly(oxytetramethylene) glycol (PTMG) and ethylene oxide addition polymers of poly(propylene oxide) glycol (PPG-EO addition polymers) are more preferred. In addition, the number average molecular weight Mn of these soft segments after copolymerization is preferably about 300 or more and about 6,000 or less. Specific examples include PTMG850 (number average molecular weight Mn: molecular weight 850), PTMG1000 (number average molecular weight Mn: 1,000), PTMG1500 (number average molecular weight Mn: 1,500), PTMG2000 (number average molecular weight Mn: 2,000), PTMG3000 (number average molecular weight Mn: 3,000), PPG (addition mole number 2)-EO (addition mole number 9) addition polymer, PPG (addition mole number 7)-EO (addition mole number 14) addition polymer, PPG (addition mole number 41)-EO (addition mole number 36) addition polymer, etc.

[0075] The amount of the aliphatic polyether used is preferably 75% by mass or more, more preferably 80% by mass or more, and particularly preferably 90% by mass or more, of the total soft segment components including other soft segment components other than the aliphatic polyether.

[0076] As other soft segment components that can be used together with the above-mentioned aliphatic polyether, for example, aliphatic polyesters such as polycaprolactone and polybutylene adipate, aliphatic polycarbonate, etc., can be mentioned. Other soft segment components are used within a range that does not impair the flexibility of the thermoplastic polyester elastomer, and the amount used is preferably 25% by mass or less of the total soft segment components, more preferably 20% by mass or less, and particularly preferably 10% by mass or less.

[0077] As a preferred embodiment of the thermoplastic polyester elastomer of the present embodiment, a block copolymer using PBT or PBN as a hard segment (A) and PTMG or PPG-EO addition polymer as a soft segment (B) can be cited. Specifically preferably, a block copolymer consisting of PBT-PTMG-PBT, a block copolymer consisting of PBT-(PPG-EO addition polymer)-PBT, a block copolymer consisting of PBN-PTMG-PBN, and a block copolymer consisting of PBN-(PPG-EO addition polymer)-PBN. From the viewpoint of ultraviolet transmittance, more preferably a block copolymer consisting of PBT-PTMG-PBT or a block copolymer consisting of PBT-(PPG-EO addition polymer)-PBT, from the viewpoint of versatility and film forming, particularly preferably a block copolymer consisting of PBT-PTMG-PBT. These thermoplastic polyester elastomers can also be used in combination of more than two kinds as needed within the range of not damaging the effect of the present invention, but from the viewpoint of film forming, it is preferably used alone.

[0078] The content (copolymerization amount) of the soft segment (B) of the thermoplastic polyester elastomer is preferably in the range of 51% by mass or more and 73% by mass or less relative to the total mass of the hard segment (A) and the soft segment (B) as the constituent components, and more preferably in the range of 55% by mass or more and 70% by mass or less. It should be noted that, in the case where the substrate film 1 is a laminate composed of multiple layers, the meaning of the content of the soft segment (B) is the value in the laminate as a whole calculated by the content of the soft segment (B) in each layer and the mass ratio of each layer in the whole layer. The mass ratio of the hard segment (A) to the soft segment (B) can be measured using an NMR measuring device. When the content of the soft segment (B) is less than 51% by mass, the bending modulus (G') of the substrate film 1 is too large, and in the semiconductor manufacturing process, the chip of the thin film wafer may be damaged and the pickup characteristics may deteriorate in the pickup process of the semiconductor chip. On the other hand, when the content of the soft segment (B) is greater than 73% by mass, the film-making of the substrate film 1 itself may become difficult. In addition, the crystal melting point of the base film 1 becomes lower, and the elongation and viscosity also become larger. Therefore, in the semiconductor manufacturing process, when the wafer is cut by a blade, as a result of cutting into the base film 1 of the dicing tape 10, the base film 1 may melt and stretch to generate filament-like cuttings, and the cuttings adhere to the semiconductor chip to reduce the reliability of the semiconductor element, or may cause recognition errors in the picking process. If the content (copolymerization amount) of the soft segment (B) of the thermoplastic polyester elastomer is within the above range, it is easy to set the bending elastic modulus (G') of the base film 1 at 23°C in the appropriate range of 10 MPa to 135 MPa.

[0079] The thermoplastic polyester elastomer can be produced by a known method. For example, the following methods can be cited: a method in which a lower alcohol diester of a dicarboxylic acid, an excess of a low molecular weight diol, and a soft segment component are subjected to an ester exchange reaction in the presence of a catalyst such as an organic acid salt or an organic metal compound, and the resulting reaction product is subjected to polycondensation in the presence of a catalyst such as an antimony compound, a titanium compound, or a germanium compound; a method in which a dicarboxylic acid, an excess of a diol, and a soft segment component are subjected to an esterification reaction in the presence of a catalyst such as an organic acid salt or an organic metal compound, and the resulting reaction product is subjected to polycondensation in the presence of a catalyst such as an antimony compound, a titanium compound, or a germanium compound; a method in which an aliphatic polyether polyol is heated and mixed with a suitable aromatic polyester obtained from an aromatic dicarboxylic acid and a low molecular weight diol component, thereby partially depolymerizing the aromatic polyester and reacting with the aliphatic polyether polyol for polycondensation; a method in which a hard segment is prepared in advance, a soft segment component is added thereto, and randomization is performed by an ester exchange reaction; a method in which a hard segment is connected to a soft segment by a chain linker, and the like. In the case of a method in which a hard segment is prepared in advance, a soft segment component is added thereto, and randomization is performed by transesterification reaction, in order to prevent excessive transesterification reaction between the hard segment and the soft segment, that is, to prevent excessive randomization from occurring and causing loss of elastomeric properties, it is preferred to prepare a hard segment in advance, add thereto a soft segment component that has been previously increased in molecular weight, and perform randomization. Specifically, the method described in Patent Gazette No. 4244067 is preferred.

[0080] <Other thermoplastic resins>

[0081] The resin constituting the substrate film 1 may contain the following exemplified thermoplastic resins as other components other than the above-mentioned thermoplastic polyester elastomer within the scope of not impairing the effect of the present invention. As such thermoplastic resins, thermoplastic resins such as polyolefin resins, polyamide resins, polycarbonate resins, homopolymers and copolymer resins containing components derived from aromatic vinyl monomers, thermoplastic elastomers other than the polyester-polyether block copolymer of the present embodiment, and poly (alkylene oxide) glycols not copolymerized with the polyester-polyether block copolymer, etc. may be cited. As the above-mentioned polyolefin resins, copolymers of polyethylene, polypropylene, ethylene and propylene, and copolymers of α-olefins having 4 to 10 carbon atoms may be cited. These polymers may be modified by acid compounds such as maleic anhydride. In addition, the polyolefin resins include metal salt ionomers. As the content of such other thermoplastic resins, it is preferably in the range of 0.1 to 10 parts by mass relative to the total amount of 100 parts by mass of the above-mentioned thermoplastic polyester elastomer contained in the substrate film 1.

[0082] <Other>

[0083] For the substrate film 1, within the scope of not impairing the effect of the present invention, from the viewpoint of operability brought by imparting smoothness (preventing adhesion), particles may be contained in the resin constituting the substrate film 1. As for the above-mentioned particles, when the substrate film 1 is a single-layer structure, it is preferably contained in the single layer, and when the substrate film 1 is a laminated structure, it is preferably contained in the outermost layer on at least one side. As the above-mentioned particles, there is no particular limitation, and inorganic particles and organic particles can be used alone or in combination. As inorganic particles, metal oxides such as silicon dioxide, aluminum oxide, titanium dioxide, and zirconium oxide; barium sulfate, calcium carbonate, aluminum silicate, calcium phosphate, mica, kaolin, clay, and zeolite can be cited. As organic particles, cross-linked particles of polymethoxysilane compounds, cross-linked particles of polyethylene compounds, cross-linked particles of polystyrene compounds, cross-linked particles of acrylic compounds, cross-linked particles of polyurethane compounds, cross-linked particles of polyester compounds, cross-linked particles of fluorine compounds, or mixtures thereof can be cited. The average particle size of the above-mentioned particles is not particularly limited, and is preferably in the range of 0.5 μm or more and 15.0 μm or less. The content of the particles is preferably in the range of 1 part by mass or more and 20 parts by mass or less based on 100 parts by mass of the total amount of the thermoplastic polyester elastomer and the thermoplastic resin contained in the base film 1 .

[0084] Furthermore, the resin constituting the substrate film 1 may contain various additives such as colorants, flame retardants, plasticizers, antistatic agents, anti-aging agents, etc. within the range that does not impair the effects of the present invention. The content of these additives is not particularly limited, but should be maintained within the range that the substrate film 1 exerts the desired function without losing flexibility.

[0085] <Flexural modulus of base film>

[0086] The base film 1 of this embodiment has a bending modulus (G') of 10 MPa to 135 MPa at 23°C when the dynamic viscoelasticity is measured using a clamped-beam bending mode at a frequency of 1 Hz and a heating rate of 0.5°C / min. If the bending modulus (G') of the base film 1 composed of a resin containing the above-mentioned thermoplastic polyester elastomer at 23°C is within the above-mentioned range, the high melting point of the base film 1 and the appropriate softness can be simultaneously satisfied. Therefore, when the base film 1 is applied to a dicing tape, it is possible to achieve both suppression of the generation of filament-like cutting chips during dicing and improvement of the pickup of semiconductor chips. From the viewpoint of further improving both properties, the bending modulus (G') of the above-mentioned base film 1 at 23°C is preferably in the range of 17 MPa to 115 MPa.

[0087] The specific method for measuring the bending elastic modulus (G') of the base film 1 is as follows.

[0088] (1) Measurement equipment

[0089] Dynamic viscoelasticity measuring device "DMA6100" (product name) manufactured by Hitachi High-Tech Science Co., Ltd.

[0090] (2) Measurement samples

[0091] Sample preparation method: A plurality of samples of the following sample sizes were cut out from the roll of the substrate film 1 after film formation, and these samples were stacked and pressed and bonded using a hot press so that the total thickness was 1.5 mm to form a laminate.

[0092] Sample size: 10mm (width) × 50mm (length) × 1.5mm (thickness)

[0093] Here, the samples of multiple substrate films 1 prepared in advance are materials cut from a position corresponding to the central part in the width direction when the substrate film 1 is processed into a roll of the cutting tape 10 in such a manner that the width direction of 10 mm in the above-mentioned sample size is consistent with the MD direction (flow direction) of the substrate film 1 during film formation, and the length direction of 50 mm in the above-mentioned sample size is consistent with the TD direction (direction perpendicular to the MD direction) of the substrate film 1 during film formation.

[0094] (3) Measurement conditions

[0095] ·Measurement mode: bending of fixed-end beam

[0096] ·Measurement frequency: 1Hz

[0097] ·Measurement temperature range: -40~40℃

[0098] Heating rate: 0.5℃ / min

[0099] ·Measurement atmosphere gas: Nitrogen

[0100] The value of the storage modulus at 23°C in the dynamic viscoelastic spectrum obtained by the above-mentioned measurement method is set as the bending modulus (G') of the base film 1. When the bending modulus (G') of the above-mentioned base film 1 at 23°C is less than 10 MPa, the transportability and operability of the base film 1 and the dicing tape 10 using the base film may be deteriorated. In addition, when a semiconductor device is manufactured using the dicing tape 10 using the base film 1, there is a concern in the process of picking up the semiconductor chip that the base film 1 of the dicing tape 10 excessively follows the bending movement of the semiconductor chip pushed up by the push-up pin from the second surface side, making it difficult to provide an opportunity to peel off from the adhesive layer 2 at the four edges of the semiconductor chip, thereby deteriorating the pick-up property. On the other hand, when the bending elastic modulus (G') of the above-mentioned base film 1 at 23°C is greater than 135 MPa, when a semiconductor device is manufactured using a dicing tape 10 using the base film 1, there is the following concern in the process of picking up the semiconductor chip: even if the dicing tape 10 is pushed up using a push pin, the curvature of the dicing tape 10 is small, making it difficult to help the four edges of the semiconductor chip to be peeled off from the adhesive layer 2, so it is necessary to further increase the push-up height, resulting in a higher risk of breakage of the semiconductor chip.

[0101] <Thickness of base film>

[0102] The thickness of the substrate film 1 of the present embodiment is not particularly limited. For example, when applied to a dicing tape, it is preferably in the range of 70 μm to 155 μm, and more preferably in the range of 80 μm to 100 μm. It should be noted that, when the substrate film 1 is a laminated structure, the thickness means the total thickness of each layer. When the thickness of the substrate film 1 is less than 70 μm, when a semiconductor device is manufactured using a dicing tape 10 using the substrate film 1, the substrate film 1 partially cut into by a cutting knife during cutting may be broken in the subsequent expansion process. On the other hand, when the thickness of the substrate film 1 is greater than 155 μm, when the dicing tape 10 is made using the substrate film 1 and wound, the core portion may produce high and low marks that lead to poor quality, and the transmittance of active energy rays such as ultraviolet rays (UV) required for the curing of the adhesive layer 2 may deteriorate. In addition, the warping caused by the release of residual stress of the substrate film 1 during film making may become larger.

[0103] When the base film 1 of the present embodiment is set as a laminate composed of multiple layers of different resins and used as the base film of the dicing tape 10 described later, it is preferred that the thickness of the layer having the first surface in contact with the adhesive layer 2 in the base film 1 is thicker than the depth of the base film 1 cut by the cutter, and the content of the soft segment (B) of the thermoplastic polyester elastomer contained in the layer is made smaller than the content of the soft segment (B) of the thermoplastic polyester elastomer contained in other layers. Therefore, when the base film 1 is used as the base film of the dicing tape 10, the crystal melting point of the resin containing the thermoplastic polyester elastomer constituting the layer having the first surface in contact with the adhesive layer 2 in the base film 1 can be maintained higher, so that the generation of silk-like cutting chips when the base film 1 is cut can be stably suppressed.

[0104] <Crystal melting point of base film>

[0105] The crystal melting point of the substrate film 1 of the present embodiment refers to the crystal melting point of the resin when the substrate film 1 is composed of only the same resin. In addition, when the substrate film 1 is a laminate composed of multiple layers of different resins, it refers to the crystal melting point of the resin constituting the layer having the first surface in contact with the adhesive layer. In detail, when the substrate film 1 of the above-mentioned laminate is used as the substrate film of the dicing tape 10 described later, it refers to the crystal melting point of the resin constituting the layer having the first surface in contact with the adhesive layer 2 in the substrate film 1 (i.e., the layer cut by the cutting knife). The crystal melting point of the above-mentioned substrate film 1 is preferably 160°C to 200°C, and more preferably 170°C to 195°C. If the crystal melting point of the substrate film 1 is less than 160°C, the substrate film 1 will easily produce silk-like cutting chips when the semiconductor wafer is fully cut using a cutting machine. If the crystal melting point of the substrate film 1 is greater than 200°C, the bending elastic modulus (G') of the substrate film 1 tends to increase. Therefore, in the picking-up process, when the cutting tape 10 is pushed up by a push pusher, the bending property of the cutting tape 10 decreases. In the picking-up process of the semiconductor chip, the pushing height needs to be increased, resulting in the semiconductor chip being easily broken.

[0106] When the base film 1 is a laminate composed of multiple layers of different resins and is used as a base film of a dicing tape 10 described later, it is preferred that the crystal melting point of the resin constituting the layer having the first surface in contact with the adhesive layer 2 in the base film 1 be made higher than the crystal melting points of the resin constituting the other layers. Thus, when the base film 1 is used as a base film of a dicing tape 10 described later, generation of filament-like cutting chips when the base film 1 is cut can be stably suppressed.

[0107] The crystal melting point of the resin can be measured, for example, using a differential scanning calorimeter "DSC-8321" (product name) manufactured by Rigaku Corporation. Specifically, first, 10 mg of the resin sample is filled in an aluminum pan, and the temperature is raised to 290°C at a heating rate of 10°C / min in a nitrogen atmosphere. After maintaining the same temperature for 3 minutes, the aluminum pan is plunged into liquid nitrogen for rapid cooling. The quenched aluminum pan is placed in the above-mentioned differential scanning calorimeter "DSC-8321" again, and the temperature is raised at a heating rate of 10°C / min. The peak temperature of the endothermic peak that appears at this time is set as the crystal melting point of the resin.

[0108] <Elongation of base film>

[0109] The substrate film 1 of the present embodiment preferably has an elongation in the MD direction and the TD direction measured by the method specified in JIS Z 0237 (2009) in a range of 300% to 700%. Here, an elongation of 100% means that the film is elongated to a length twice the original length. In addition, as mentioned above, the MD direction refers to the flow direction of the substrate film 1 during film formation, and the TD direction refers to the direction perpendicular to the MD direction. In the case where the elongation of the substrate film 1 is less than 300%, the substrate film 1 tends to harden, so the expandability as a dicing tape and the pick-up property of the semiconductor chip may be deteriorated. On the other hand, in the case where the elongation of the substrate film 1 is greater than 700%, the elongation and viscosity of the substrate film 1 increase, so that silk-like cutting chips may be easily generated during cutting.

[0110] <Ultraviolet transmittance of base film>

[0111] For the substrate film 1 of the present embodiment, when the active energy ray curable adhesive composition described later is applied as the adhesive layer 2, it is necessary to transmit the active energy ray. In this case, specifically, for example, when ultraviolet rays (UV) are used as active energy rays, the parallel light transmittance of the ultraviolet rays of the substrate film 1 measured by a spectrophotometer is preferably 1% or more at a wavelength of 365nm, and more preferably 5% or more. In the case where the parallel light transmittance of the ultraviolet rays of the above-mentioned substrate film 1 is less than 1%, even if ultraviolet rays are irradiated from the substrate film 1 side of the dicing tape 10, the ultraviolet rays will not fully reach the adhesive layer 2 containing the active energy ray curable adhesive composition, so there is the following concern: the adhesive layer 2 will not be fully cured and shrunk, and the adhesion to the adherend will not be fully reduced. As a result, in the process (pick-up process) of peeling off the semiconductor chip or the semiconductor chip with the adhesive layer from the adhesive layer 2, the semiconductor chip or the semiconductor chip with the adhesive layer may be poorly picked up. When the parallel light transmittance of ultraviolet rays of the substrate film 1 is 1% or more, the adhesive layer 2 containing the active energy ray-curable adhesive composition can be sufficiently cured and shrunk, so that the adhesive force to the adherend can be sufficiently reduced. As a result, the pickup property of the semiconductor chip or the semiconductor chip with the adhesive layer becomes good.

[0112] <Method for forming substrate film>

[0113] As a film-forming method of the substrate film 1 of the present embodiment, conventional manufacturing methods such as a casting method, a T-die method, an inflation method, and a calendaring method can be cited. Among them, the casting method is preferably used for film-forming because shear stress is not applied during film-forming of the substrate film 1 and polymer molecules are not oriented, and the substrate film 1 can be uniformly extended without breaking when expanded.

[0114] Specifically, for example, after drying the pellets of the resin that will be the material of the base film 1 as needed, the molten resin extruded at a temperature of 190 to 300° C. using an extruder such as a T-die is cooled by clamping and pressing or by a single or multiple casting drums at a temperature of 30 to 70° C. in a single-sided contact manner, thereby substantially not stretching the film and producing a non-stretched film. During casting, by using an electrostatic bonding method, an air knife method, or a suction chamber method, a base film 1 with a small thickness deviation can be obtained.

[0115] When the base film 1 has a laminated structure, a conventional film lamination method such as a coextrusion method or a dry lamination method can be used as a method for forming the base film 1 .

[0116] Furthermore, in order to stabilize the winding of the substrate film 1 during film formation and prevent adhesion after film formation, a method of embossing the surface (second surface) opposite to the side (first surface) on which the adhesive layer 2 is provided and winding the substrate film 1, or a method of laminating the substrate film 1 on a process release paper and winding the substrate film 1 can also be used. As the process release paper, a stretched polyester sheet generally referred to as O-PET, a stretched polypropylene sheet generally referred to as OPP, a process release paper formed of paper, or a process release paper formed by coating an olefin resin or a silicone resin on paper can be appropriately used. The process release paper can be peeled off when the cutting tape 10 is supplied to, for example, a cutting process after the substrate film 1 is formed into the shape of the cutting tape 10.

[0117] Cutting Strip

[0118] The dicing tape 10 of the present invention has an adhesive layer 2 for holding (temporarily fixing) a semiconductor wafer 30 on the first surface of the above-mentioned base film 1. In addition, a base sheet (release liner) having a demoulding property may be provided on the surface of the adhesive layer 2 of the dicing tape 10. As an adhesive forming the above-mentioned adhesive layer 2, a conventionally known adhesive can be used as the adhesive of the dicing tape 10. As such an adhesive, there is no particular limitation, and various adhesive compositions such as acrylic, silicone, polyester, polyvinyl acetate, polyurethane, and rubber can be used. Among them, from the viewpoint of versatility and practicality, an acrylic adhesive composition can be suitably used.

[0119] <Adhesive layer>

[0120] As the acrylic adhesive composition applied to the adhesive layer 2 of the present embodiment, both the known or conventional active energy ray non-curable acrylic adhesive composition and the active energy ray curable acrylic adhesive composition can be used. Here, the meaning of "active energy ray curable acrylic adhesive composition" is an adhesive composition that is cross-linked and cured by irradiating active energy rays such as ultraviolet rays, visible rays, infrared rays, electron rays, beta rays, and gamma rays, and the adhesive force decreases, that is, an acrylic adhesive composition with a photosensitive carbon-carbon double bond. In addition, the meaning of "active energy ray non-curable acrylic adhesive composition" is an adhesive composition that does not decrease in adhesion even if irradiated with active energy rays, that is, an acrylic adhesive composition without a photosensitive carbon-carbon double bond. In the pickup process of the semiconductor chip, from the viewpoint of improving the pickup success rate (improving pickup) that the semiconductor chip can be easily picked up without damage, it is preferred to use an active energy ray curable acrylic adhesive composition.

[0121] (Active energy ray non-curable acrylic adhesive composition)

[0122] As an active energy ray non-curable acrylic adhesive composition, a so-called common acrylic adhesive composition comprising an acrylic adhesive polymer having a functional group and a crosslinking agent that reacts with the functional group can be cited, but it is not particularly limited thereto. The functional group mentioned here refers to a thermally reactive functional group. Examples of such functional groups include active hydrogen groups such as hydroxyl, carboxyl and amino groups; and functional groups such as glycidyl groups that react thermally with active hydrogen groups. Active hydrogen groups refer to functional groups having elements other than carbon, such as nitrogen, oxygen or sulfur, and hydrogen directly bonded thereto.

[0123] [Acrylic adhesive polymer having functional group]

[0124] The main skeleton of the acrylic adhesive polymer having a functional group is composed of a copolymer containing an alkyl (meth)acrylate monomer and an active hydrogen group-containing monomer and / or a glycidyl group-containing monomer. Examples of the alkyl (meth)acrylate monomer include hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, and octadecyl (meth)acrylate, which have 6 to 18 carbon atoms; or pentyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, ethyl (meth)acrylate, and methyl (meth)acrylate, which have 5 or less carbon atoms. In addition, examples of the active hydrogen group-containing monomer include hydroxyl group-containing monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate; carboxyl group-containing monomers such as (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid; acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; amide monomers such as (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N-butyl (meth)acrylamide, N-hydroxymethyl (meth)acrylamide, N-methylolpropane (meth)acrylamide, N-methoxymethyl (meth)acrylamide, and N-butoxymethyl (meth)acrylamide; amino group-containing monomers such as aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, and tert-butylaminoethyl (meth)acrylate, etc. These active hydrogen group-containing monomer components may be used alone or in combination of two or more. Examples of the glycidyl group-containing monomer include glycidyl (meth)acrylate, etc. The content of the thermally reactive functional group is not particularly limited, but is preferably in the range of 0.5% by mass to 50% by mass based on the total amount of the comonomer components.

[0125] Specific preferred copolymers obtained by copolymerizing the above monomers include copolymers of 2-ethylhexyl acrylate and acrylic acid, copolymers of 2-ethylhexyl acrylate and 2-hydroxyethyl acrylate, terpolymers of 2-ethylhexyl acrylate, methacrylic acid and 2-hydroxyethyl acrylate, copolymers of n-butyl acrylate and acrylic acid, copolymers of n-butyl acrylate and 2-hydroxyethyl acrylate, terpolymers of n-butyl acrylate, methacrylic acid and 2-hydroxyethyl acrylate, etc., but are not particularly limited to these.

[0126] For the purpose of cohesion and heat resistance, the above-mentioned acrylic adhesive polymer with functional groups may contain other comonomer components as needed. As such other comonomer components, specifically, there can be cited cyano monomers such as (meth)acrylonitrile; olefin monomers such as ethylene, propylene, isoprene, butadiene, isobutylene; styrene monomers such as styrene, α-methylstyrene, vinyltoluene; vinyl ester monomers such as vinyl acetate and vinyl propionate; vinyl ether monomers such as methyl vinyl ether and ethyl vinyl ether; halogen-containing monomers such as vinyl chloride and vinylidene chloride; alkoxy-containing monomers such as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate; N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyl The present invention relates to monomers having nitrogen atom rings such as oxazole, N-vinyl morpholine, N-vinyl caprolactam, and N-(methyl)acryloyl morpholine. These other copolymerization monomer components can be used alone or in combination of two or more. The glass transition temperature (Tg) of the acrylic adhesive polymer having a functional group is preferably in the range of -70°C to 15°C, more preferably in the range of -60°C to -10°C.

[0127] [Crosslinking agent]

[0128] For the high molecular weight of the above-mentioned acrylic acid adhesive polymer with functional group, the active energy ray non-curable acrylic acid adhesive composition of the present embodiment further contains a crosslinking agent. As such a crosslinking agent, there is no particular restriction, and a known crosslinking agent with a functional group that can react with a hydroxyl, a carboxyl and a glycidyl group as the functional group possessed by the above-mentioned acrylic acid adhesive polymer can be used. Specifically, for example, polyisocyanate crosslinking agents, epoxy crosslinking agents, aziridine crosslinking agents, melamine resin crosslinking agents, urea resin crosslinking agents, anhydride compound crosslinking agents, polyamine crosslinking agents, carboxyl-containing polymer crosslinking agents, etc. can be cited. Among them, from the viewpoint of reactivity and versatility, it is preferred to use polyisocyanate crosslinking agents or epoxy crosslinking agents. These crosslinking agents can be used alone or with more than 2 kinds and used in combination. The amount of the crosslinking agent is preferably in the range of 0.01 mass parts or more and 15 mass parts or less relative to 100 mass parts of the solid content of the acrylic acid adhesive polymer.

[0129] As the above-mentioned polyisocyanate-based crosslinking agent, for example, polyisocyanate compounds having an isocyanurate ring, addition polyisocyanate compounds formed by reacting trimethylolpropane with hexamethylene diisocyanate, addition polyisocyanate compounds formed by reacting trimethylolpropane with toluene diisocyanate, addition polyisocyanate compounds formed by reacting trimethylolpropane with xylene diisocyanate, addition polyisocyanate compounds formed by reacting trimethylolpropane with isophorone diisocyanate, etc. These can be used alone or in combination of two or more.

[0130] Examples of the epoxy crosslinking agent include bisphenol A-epichlorohydrin epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerol diglycidyl ether, glycerol triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl erythritol, diglycerol polyglycidyl ether, 1,3′-bis(N,N-diglycidylaminomethyl)cyclohexane, and N,N,N′,N′-tetraglycidyl-m-xylenediamine. These can be used alone or in combination of two or more.

[0131] After forming the adhesive layer 2 using the above-mentioned active energy ray non-curing resin composition, the aging conditions for reacting the above-mentioned cross-linking agent with the above-mentioned acrylic adhesive polymer having a functional group are not particularly limited, and for example, they can be appropriately set within the range of a temperature of not less than 23° C. and not more than 80° C. and a time of not less than 24 hours and not more than 168 hours.

[0132] [other]

[0133] The active energy ray non-curable acrylic adhesive composition of the present embodiment may further contain additives such as tackifiers, fillers, antioxidants, colorants, flame retardants, antistatic agents, surfactants, silane coupling agents, and leveling agents as needed within a range that does not impair the effects of the present invention.

[0134] (Active energy ray-curable acrylic adhesive composition)

[0135] As active energy ray-curable acrylic adhesive compositions, typically, there can be cited: an adhesive composition (A) comprising an acrylic adhesive polymer having a photosensitive carbon-carbon double bond and a functional group, a photopolymerization initiator, and a crosslinking agent that reacts with the functional group; or an adhesive composition (B) comprising an acrylic adhesive polymer having a functional group, an active energy ray-curable compound, a photopolymerization initiator, and a crosslinking agent that reacts with the functional group, etc., but it is not particularly limited to these. Among them, from the viewpoint of suppressing the residual adhesive on the semiconductor wafer, the adhesive composition (A) of the former mode is preferred.

[0136] (Adhesive composition (A))

[0137] [Acrylic adhesive polymer having carbon-carbon double bond and functional group]

[0138] The acrylic adhesive polymer having a carbon-carbon double bond and a functional group of the adhesive composition (A) uses a compound having a carbon-carbon double bond in a molecular side chain. There is no particular limitation on the method for manufacturing the acrylic adhesive polymer having a carbon-carbon double bond, and a method of obtaining a copolymer by copolymerizing a (methyl)acrylate with an unsaturated compound containing a functional group, and subjecting a compound having a functional group and a carbon-carbon double bond that can undergo an addition reaction with the functional group possessed by the copolymer to an addition reaction can be cited. Here, as the above-mentioned copolymer before subjecting the compound having a functional group and a carbon-carbon double bond to an addition reaction, a copolymer identical to the copolymer exemplified as the acrylic adhesive polymer having a functional group in the description of the above-mentioned active energy ray non-curable acrylic adhesive composition can be used.

[0139] The functional group referred to here refers to a thermally reactive functional group that can coexist with a carbon-carbon double bond. Examples of such functional groups include active hydrogen groups such as hydroxyl, carboxyl and amino groups; and functional groups that react thermally with active hydrogen groups such as glycidyl groups. Active hydrogen groups refer to functional groups that have an element other than carbon, such as nitrogen, oxygen or sulfur, and hydrogen directly bonded to the element.

[0140] As the above-mentioned addition reaction, for example, there are methods of reacting a hydroxyl group located in the side chain of the above-mentioned copolymer (acrylic adhesive polymer) with an isocyanate compound having a (meth)acryloyloxy group (for example, 2-methacryloyloxyethyl isocyanate, 4-methacryloyloxy n-butyl isocyanate, etc.), a method of reacting a carboxyl group located in the side chain of the above-mentioned copolymer with glycidyl (meth)acrylate, a method of reacting a glycidyl group located in the side chain of the above-mentioned copolymer with (meth)acrylic acid, etc. It should be noted that when performing these reactions, in order to crosslink the above-mentioned acrylic adhesive polymer with a crosslinking agent such as a polyisocyanate crosslinking agent and an epoxy crosslinking agent to further increase the molecular weight, it is preferred that functional groups such as hydroxyl groups, carboxyl groups, and glycidyl groups remain in advance. For example, when an isocyanate compound having a (meth)acryloyloxy group is reacted with a copolymer having a hydroxyl group in a side chain, the mixing ratio of the two can be adjusted so that the equivalent ratio [(NCO) / (OH)] of the isocyanate compound having a (meth)acryloyloxy group to the hydroxyl group (-OH) in the side chain of the copolymer is less than 1.0. In this way, an acrylic adhesive polymer having an active energy ray reactive group (carbon-carbon double bond) such as a (meth)acryloyloxy group and a functional group can be obtained.

[0141] In the above addition reaction, in order to maintain the active energy ray reactivity of the carbon-carbon double bond, a polymerization inhibitor is preferably used. As such a polymerization inhibitor, a quinone-based polymerization inhibitor such as hydroquinone-monomethyl ether is preferred. The amount of the polymerization inhibitor is not particularly limited, and is generally preferably in the range of 0.01 mass parts or more and 0.1 mass parts or less relative to the total amount of the base polymer and the radiation-reactive compound.

[0142] The acrylic adhesive polymer (sometimes also referred to as active energy ray curing acrylic adhesive polymer) having a carbon-carbon double bond and a functional group preferably has a weight average molecular weight Mw in the range of 100,000 to 2,000,000. In the case where the weight average molecular weight Mw of the acrylic adhesive polymer is less than 100,000, it is difficult to obtain a solution of a high viscosity active energy ray curing resin composition of more than several thousand cP and less than tens of thousands of cP in consideration of coating properties, etc., and it is not preferred. In addition, there is the following situation: the cohesive force of the adhesive layer 2 before the active energy ray irradiation becomes smaller, and when cutting the semiconductor wafer, the semiconductor chip is easily offset, making it difficult to perform image recognition. On the other hand, in the case where the weight average molecular weight Mw is greater than 2,000,000, there is no particular problem in terms of the characteristics of the adhesive, but it is difficult to mass produce the acrylic adhesive polymer, for example, the acrylic adhesive polymer is sometimes gelled during synthesis, and is therefore not preferred. The weight average molecular weight Mw of the acrylic adhesive polymer is more preferably 300,000 to 1,500,000. Here, the weight average molecular weight Mw means a value in terms of standard polystyrene measured by gel permeation chromatography.

[0143] The carbon-carbon double bond content of the acrylic adhesive polymer having carbon-carbon double bonds and functional groups can be any amount that can obtain a sufficient adhesive force reduction effect in the adhesive layer 2 after irradiation with active energy rays. It varies depending on the use conditions such as the irradiation amount of active energy rays, and is not unique. The carbon-carbon double bond content is preferably in the range of 0.10 meq / g to 2.00 meq / g, and more preferably in the range of 0.50 meq / g to 1.50 meq / g. When the carbon-carbon double bond content is less than 0.10 meq / g, the adhesive force reduction effect in the adhesive layer 2 after irradiation with active energy rays becomes small, and the pickup failure of the semiconductor chip may increase. On the other hand, when the carbon-carbon double bond content is greater than 2.00 meq / g, the following problems may occur: the fluidity of the adhesive in the adhesive layer 2 after irradiation with active energy rays is insufficient, the gap between the semiconductor chips after the expansion of the dicing tape 10 or the dicing chip pasting film 20 is not sufficiently expanded, and it is difficult to perform image recognition of each semiconductor chip when picking up. In addition, there are cases where it is easy to polymerize during synthesis or gel during reaction depending on the copolymer composition of the acrylic adhesive polymer, making it difficult to synthesize. It should be noted that when the carbon-carbon double bond content of the acrylic adhesive polymer is confirmed, the carbon-carbon double bond content can be calculated by measuring the iodine value of the acrylic adhesive polymer.

[0144] Further, with respect to the acrylic adhesive polymer with carbon-carbon double bond and functional group, in order to further increase the molecular weight by crosslinking the acrylic adhesive polymer with crosslinking agents such as polyisocyanate crosslinking agent and epoxy crosslinking agent as described above, it is preferred that functional groups such as hydroxyl, carboxyl, glycidyl are left in advance. Among them, hydroxyl and carboxyl are more preferred. As the hydroxyl value of the acrylic adhesive polymer with carbon-carbon double bond and functional group, it is not particularly limited, and it is preferably in the range of 5mgKOH / g to 100mgKOH / g. In addition, as the acid value of the acrylic adhesive polymer with carbon-carbon double bond and functional group, it is not particularly limited, and it is preferably in the range of 0.5mgKOH / g to 30mgKOH / g. If the hydroxyl value and acid value of the acrylic adhesive polymer with carbon-carbon double bond and functional group are respectively in the above range, the adhesive force of the adhesive layer 2 after the active energy ray irradiation is stably reduced, and as a result, the pickup of the semiconductor chip can be further reduced, so it is preferred.

[0145] [Photopolymerization initiator]

[0146] The active energy ray-curable acrylic adhesive composition (adhesive composition (A)) of the present embodiment contains a photopolymerization initiator that generates free radicals by irradiation with active energy rays. The photopolymerization initiator generates free radicals upon irradiation of the active energy ray with the active energy ray-curable acrylic adhesive composition, thereby initiating a crosslinking reaction of carbon-carbon double bonds of the active energy ray-curable acrylic adhesive polymer.

[0147] As the above-mentioned photopolymerization initiator, there is no particular limitation, and a conventionally known photopolymerization initiator can be used. For example, alkyl phenone-based free radical polymerization initiators, acylphosphine oxide-based free radical polymerization initiators, oxime ester-based free radical polymerization initiators, etc. can be cited. As alkyl phenone-based free radical polymerization initiators, benzylmethyl ketal-based free radical polymerization initiators, α-hydroxyalkyl phenone-based free radical polymerization initiators, aminoalkyl phenone-based free radical polymerization initiators, etc. can be cited. As benzylmethyl ketal-based free radical polymerization initiators, specifically, for example, 2,2'-dimethoxy-1,2-diphenylethane-1-one (for example, trade name Omnirad651, manufactured by IGM Resins BV) and the like can be cited. Specific examples of the α-hydroxyalkylphenone-based radical polymerization initiator include 2-hydroxy-2-methyl-1-phenylpropane-1-one (trade name Omnirad 1173, manufactured by IGM Resins BV), 1-hydroxycyclohexyl phenyl ketone (trade name Omnirad 184, manufactured by IGM Resins BV), 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propane-1-one (trade name Omnirad 2959, manufactured by IGM Resins BV), and 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropanoyl)benzyl]phenyl}-2-methylpropane-1-one (trade name Omnirad 127, manufactured by IGM Resins BV). Specific examples of the aminoalkylphenone-based radical polymerization initiator include 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one (trade name Omnirad 907, manufactured by IGM Resins BV) and 2-benzylmethyl 2-dimethylamino-1-(4-morpholinophenyl)-1-butanone (trade name Omnirad 369, manufactured by IGM Resins BV). As the acylphosphine oxide-based radical polymerization initiator, specifically, for example, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (trade name Omnirad TPO, manufactured by IGM Resins BV) and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (trade name Omnirad 819, manufactured by IGM Resins BV) can be mentioned, and as the oxime ester-based radical polymerization initiator, (2E)-2-(benzoyloxyimino)-1-[4-(phenylthio)phenyl]octan-1-one (trade name Omnirad OXE-01, manufactured by IGM Resins BV) can be mentioned. These photopolymerization initiators can be used alone or in combination of two or more.

[0148] The amount of the photopolymerization initiator added is preferably in the range of 0.1 to 10.0 parts by mass relative to 100 parts by mass of the solid content of the active energy ray-curable acrylic adhesive polymer. When the amount of the photopolymerization initiator added is less than 0.1 parts by mass, the photoreactivity to the active energy rays is insufficient, so even if the active energy rays are irradiated, the photoradical crosslinking reaction of the acrylic adhesive polymer will not be fully induced. As a result, the adhesive force reduction effect in the adhesive layer 2 after the active energy ray irradiation becomes smaller, and the pickup failure of the semiconductor chip may increase. On the other hand, when the amount of the photopolymerization initiator added is greater than 10.0 parts by mass, the effect is saturated, which is not preferred from the viewpoint of economy. In addition, depending on the type of the photopolymerization initiator, the adhesive layer 2 sometimes turns yellow and has a poor appearance.

[0149] Furthermore, as a sensitizer for such a photopolymerization initiator, a compound such as dimethylaminoethyl methacrylate and isopentyl 4-dimethylaminobenzoate may be added to the active energy ray-curable acrylic adhesive composition.

[0150] [Crosslinking agent]

[0151] In order to make the above-mentioned active energy ray-curable acrylic adhesive polymer high molecular weight, the active energy ray-curable acrylic adhesive composition (adhesive composition (A)) of the present embodiment further contains a cross-linking agent. As the above-mentioned cross-linking agent, the same cross-linking agent as the cross-linking agent exemplified as the cross-linking agent in the description of the above-mentioned active energy ray non-curable acrylic adhesive composition can be used. In addition, the amount of the cross-linking agent and the aging conditions for reacting the cross-linking agent with the active energy ray-curable acrylic adhesive polymer can also be the same.

[0152] [other]

[0153] The active energy ray-curable acrylic adhesive composition (adhesive composition (A)) of the present embodiment may further contain additives such as multifunctional acrylic monomers, multifunctional acrylic oligomers, tackifiers, fillers, antioxidants, colorants, flame retardants, antistatic agents, surfactants, silane coupling agents, and leveling agents as needed within the range that does not impair the effects of the present invention.

[0154] (Adhesive composition (B))

[0155] [Acrylic adhesive polymer having functional group]

[0156] As the acrylic adhesive polymer having a functional group of the adhesive composition (B), the same polymer as exemplified as the acrylic adhesive polymer having a functional group in the description of the active energy ray non-curable acrylic adhesive composition can be used.

[0157] [Active energy ray-curable compound]

[0158] As the active energy ray curable compound of the above-mentioned adhesive composition (B), for example, a low molecular weight compound having at least two or more carbon-carbon double bonds in the molecule that can be three-dimensionally reticulated by irradiating active energy rays can be widely used. As active energy ray curable compounds, specifically, esters of (meth) acrylic acid and polyols such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and dipentaerythritol hexa(meth)acrylate can be cited; 2-propenyl-di-3-butenyl cyanurate, 2-hydroxyethyl bis(2-acryloyloxyethyl) isocyanurate, tris(2-methacryloyloxyethyl) isocyanurate, etc. isocyanurate or isocyanurate compounds, etc. These active energy ray curable compounds can be used alone or in combination of two or more.

[0159] In addition, as active energy ray curable compounds, in addition to the above-mentioned compounds, active energy ray curable oligomers such as epoxy acrylate oligomers, urethane acrylate oligomers, and polyester acrylate oligomers can also be used. Epoxy acrylate is synthesized by the addition reaction of epoxy compound and (meth) acrylic acid. Urethane acrylate is synthesized by, for example, reacting the isocyanate group remaining at the end with hydroxyl-containing (meth) acrylic acid ester in the addition reaction product of polyol and polyisocyanate and introducing (meth) acryloyl group at the molecular end. Polyester acrylate is synthesized by the reaction of polyester polyol and (meth) acrylic acid. From the viewpoint of the adhesive force reduction effect of the adhesive layer 2 after active energy ray irradiation, the above-mentioned active energy ray curable oligomer preferably has more than 3 carbon-carbon double bonds in the molecule. These active energy ray curable oligomers can be used alone or in combination of two or more.

[0160] The weight average molecular weight Mw of the active energy ray-curable oligomer is not particularly limited, but is preferably in the range of 100 to 30,000. From the viewpoints of suppressing contamination of the semiconductor chip and reducing the adhesive force of the adhesive layer 2 after active energy ray irradiation, it is more preferably in the range of 500 to 6,000.

[0161] The hydroxyl value of the active energy ray curable oligomer is not particularly limited, and is preferably 3 mgKOH / g or less when the dicing tape 10 is attached immediately after the semiconductor wafer is ground. That is, the surface of the semiconductor wafer just after grinding is extremely active, and the fewer the hydroxyl groups (hydroxyl groups of the active energy ray curable oligomers) bonded to the active atoms of the active surface in the adhesive layer 2, the more the adhesive force of the adhesive layer 2 after the active energy ray irradiation can be suppressed from excessively increasing, thereby making it easy to peel the semiconductor chip from the adhesive layer 2. As the hydroxyl value of the active energy ray curable oligomer, 0 mgKOH / g is more preferred.

[0162] The content of the active energy ray-curable compound is 5 parts by mass or more and 500 parts by mass or less, preferably 50 parts by mass or more and 180 parts by mass or less, relative to 100 parts by mass of the acrylic adhesive polymer having a functional group. When the content of the active energy ray-curable compound is within the above range, the adhesive force of the adhesive layer 2 can be appropriately reduced after irradiation with active energy rays, and the semiconductor chip can be easily picked up without damaging it.

[0163] [Photopolymerization initiator]

[0164] The active energy ray-curable acrylic adhesive composition (adhesive composition (B)) of the present embodiment contains a photopolymerization initiator that generates free radicals by irradiation with active energy rays. As the above-mentioned photopolymerization initiator, the same photopolymerization initiator as the photopolymerization initiator exemplified in the description of the above-mentioned active energy ray-curable acrylic adhesive composition (adhesive composition (A)) can be used. In addition, the addition amount of the photopolymerization initiator can also be the same.

[0165] [Crosslinking agent]

[0166] In order to make the above-mentioned active energy ray-curable acrylic adhesive polymer high molecular weight, the active energy ray-curable acrylic adhesive composition (adhesive composition (B)) of the present embodiment further contains a cross-linking agent. As the above-mentioned cross-linking agent, the same cross-linking agent as the cross-linking agent exemplified as the cross-linking agent in the description of the above-mentioned active energy ray non-curable acrylic adhesive composition can be used. In addition, the amount of the cross-linking agent and the aging conditions for reacting the cross-linking agent with the active energy ray-curable acrylic adhesive polymer can also be the same.

[0167] [other]

[0168] The active energy ray-curable acrylic adhesive composition (adhesive composition (B) of the present embodiment may further contain additives such as a tackifier, a filler, an antioxidant, a colorant, a flame retardant, an antistatic agent, a surfactant, a silane coupling agent, and a leveling agent as needed within the range not impairing the effects of the present invention.

[0169] (Thickness of adhesive layer)

[0170] The thickness of the adhesive layer 2 of the present embodiment is not particularly limited, and is preferably in the range of 3 μm to 50 μm, and more preferably in the range of 5 μm to 20 μm. When the thickness of the adhesive layer 2 is less than 3 μm, the adhesion of the dicing tape 10 may be excessively reduced. In this case, for example, when cutting a semiconductor wafer, the dicing tape 10 cannot fully hold the semiconductor chip, and the semiconductor chip may fly. In addition, when used as a chip pasting film for cutting, poor adhesion between the adhesive layer 2 and the chip pasting film 3 sometimes occurs. On the other hand, when the thickness of the adhesive layer 2 is greater than 50 μm, the vibration during cutting is easily transmitted to the adhesive layer 2, the amplitude becomes larger, and the semiconductor wafer may be offset from the reference position during the cutting of the semiconductor wafer. In this case, the semiconductor chip may be defective (debris) and the size of each semiconductor chip may deviate.

[0171] <Anchor coating>

[0172] In the dicing tape 10 of the present embodiment, an anchor coating layer adapted to the composition of the base film 1 may be provided between the base film 1 and the adhesive layer 2, depending on the manufacturing conditions of the dicing tape 10, the use conditions of the manufactured dicing tape 10, and the like. By providing the anchor coating layer, the adhesion between the base film 1 and the adhesive layer 2 is improved.

[0173] <Release liner>

[0174] In addition, a release liner may be provided as needed on the surface side (surface side of one side) of the adhesive layer 2 opposite to the substrate film 1. The material that can be used as the release liner is not particularly limited, and synthetic resins such as polyethylene, polypropylene, and polyethylene terephthalate, paper, etc., can be cited. In addition, on the surface of the release liner, in order to improve the releasability of the adhesive layer 2, a release treatment using a silicone-based release treatment agent, a long-chain alkyl-based release treatment agent, a fluorine-based release treatment agent, etc. can be implemented. The thickness of the release liner is not particularly limited, and a release liner in the range of more than 10 μm and less than 200 μm can be appropriately used.

[0175] <Method for manufacturing dicing tape>

[0176] Figure 4Flowchart for explaining the manufacturing method of the dicing tape 10. First, a release liner is prepared (step S101: release liner preparation process). Next, a coating solution for the adhesive layer 2 (coating solution for adhesive layer formation) is prepared as a forming material of the adhesive layer 2 (step S102: coating solution preparation process). The coating solution can be prepared by, for example, uniformly mixing and stirring an acrylic adhesive polymer, a cross-linking agent, and a diluting solvent as constituents of the adhesive layer 2. As a solvent, a general-purpose organic solvent such as toluene and ethyl acetate can be used.

[0177] Then, using the coating solution for the adhesive layer 2 prepared in step S102, the coating solution is applied to the release treated surface of the release liner and dried to form an adhesive layer 2 of a predetermined thickness (step 103: adhesive layer forming process). There is no particular limitation on the coating method, and coating can be performed using, for example, a die coater, a notch wheel coater (registered trademark), a gravure coater, a roller coater, a reverse coater, etc. In addition, there are no particular limitations on the drying conditions, and for example, the drying temperature is preferably within the range of 80°C to 150°C and the drying time is preferably within the range of 0.5 minutes to 5 minutes. Next, prepare the substrate film 1 (step S104: substrate film preparation process). Then, laminate the substrate film 1 onto the adhesive layer 2 formed on the release liner (step S105: substrate film laminating process). Here, when a base film of a laminate composed of multiple layers of different resins is used as the base film 1, the surface (first surface) of the layer side composed of a resin having a crystal melting point in the range of 160°C to 200°C is bonded to the adhesive layer 2. Finally, the formed adhesive layer 2 is aged for 72 hours in an environment of, for example, 40°C to allow the acrylic adhesive polymer to react with the crosslinking agent to crosslink and cure (step S106: thermal curing process). The above process can be used to produce a cutting tape 10 having an adhesive layer 2 and a release liner on the base film 1 in sequence from the base film side. It should be noted that in the present invention, the laminate having a release liner on the adhesive layer 2 is sometimes also referred to as a cutting tape 10.

[0178] It should be noted that, as a method for forming the adhesive layer 3 on the above-mentioned base film 1, a method of applying a coating solution for the adhesive layer 2 on a release liner and drying it, and then laminating the base film 1 on the adhesive layer 2 is exemplified, but a method of directly applying a coating solution for the adhesive layer 2 on the base film 1 and drying it may also be used. From the viewpoint of stable production, the former method is preferably used.

[0179] The dicing tape 10 of this embodiment may be in the form of a roll or a wide sheet stack. In addition, the dicing tape 10 of these forms may be cut into a sheet or tape form of a predetermined size.

[0180] 《Chip Paste Film for Dicing》

[0181] In the semiconductor manufacturing process, the dicing tape 10 of the present embodiment can also be used as a dicing chip pasting film 20 in which a chip pasting film (adhesive layer) 3 is laminated and releasably adhered to the adhesive layer 2 of the dicing tape 10. The chip pasting film (adhesive layer) 3 is used to bond and connect the semiconductor chip singulated after dicing to the lead frame and the wiring substrate. In addition, in the case of stacking semiconductor chips, it also serves as an adhesive layer between the semiconductor chips. Below, an example of the chip pasting film (adhesive layer) 3 when the dicing tape 10 of the present embodiment is used as a dicing chip pasting film 20 is shown, but it is not particularly limited to this example.

[0182] <Chip attach film (adhesive layer)>

[0183] The chip pasting film (adhesive layer) 3 is a layer composed of a thermosetting adhesive composition that is cured by heat. As the above-mentioned adhesive composition, there is no particular limitation, and previously known materials can be used. As an example of a preferred embodiment of the above-mentioned adhesive composition, for example, a thermosetting resin composition can be cited, which contains a glycidyl (meth) acrylate copolymer as a thermoplastic resin, an epoxy resin as a thermosetting resin, and a curing agent for the epoxy resin as a curing agent. The chip pasting film (adhesive layer) 3 having such a composition has the following characteristics and is preferred: excellent adhesion between the semiconductor chip / support substrate and between the semiconductor chip / semiconductor chip, and can also impart electrode embedding and / or lead embedding, etc., and can be bonded at low temperature in the chip pasting process, excellent curing can be obtained in a short time, and excellent reliability can be obtained after being fixed with a sealant, etc.

[0184] (Copolymer containing glycidyl (meth)acrylate)

[0185] The glycidyl (meth)acrylate copolymer preferably contains at least an alkyl (meth)acrylate having an alkyl group with 1 to 8 carbon atoms and glycidyl (meth)acrylate as copolymer units. From the viewpoint of ensuring appropriate adhesive force, the copolymer unit of glycidyl (meth)acrylate is preferably contained in a range of 0.5 mass % to 6.0 mass % in the total amount of the glycidyl (meth)acrylate copolymer. In addition, from the viewpoint of adjusting the glass transition temperature (Tg), the glycidyl (meth)acrylate copolymer may contain other monomers such as styrene and acrylonitrile as copolymer units as needed.

[0186] The glass transition temperature (Tg) of the glycidyl group-containing (meth)acrylate copolymer is preferably in the range of -50°C to 30°C, and more preferably in the range of -10°C to 30°C from the viewpoint of improving the handleability as a die attach film (suppressing tackiness). In order to adjust the glycidyl group-containing (meth)acrylate copolymer to such a glass transition temperature, ethyl (meth)acrylate and / or butyl (meth)acrylate are preferably used as the (meth)acrylate alkyl ester having an alkyl group having 1 to 8 carbon atoms.

[0187] The weight average molecular weight Mw of the above-mentioned glycidyl (meth) acrylate copolymer is preferably in the range of 100,000 to 3,000,000, and more preferably in the range of 500,000 to 2,000,000. If the weight average molecular weight Mw is within the above range, it is easy to make the adhesion, heat resistance and fluidity suitable. Here, the meaning of the weight average molecular weight Mw is the standard polystyrene conversion value measured by gel permeation chromatography.

[0188] The content ratio of the glycidyl group-containing (meth)acrylate copolymer in the die attach film (adhesive layer) 3 is preferably in the range of 50 mass % to 95 mass %, more preferably in the range of 50 mass % to 90 mass %.

[0189] (Epoxy resin)

[0190] As epoxy resin, there is no particular limitation, and for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, phenol novolac type epoxy resin, alkylphenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, diglycidyl etherification of biphenol, diglycidyl etherification of naphthalene diol, diglycidyl etherification of phenols, diglycidyl etherification of alcohols and their alkyl substitutions, halides, hydrides and other difunctional epoxy resins, novolac type epoxy resins etc. can be enumerated. In addition, generally known other epoxy resins such as multifunctional epoxy resins and heterocyclic epoxy resins can also be used. They can be used alone, or two or more can be used in combination.

[0191] From the viewpoint of properly performing the function as a thermosetting adhesive in the chip pasting film (adhesive layer) 3, the content ratio of the above-mentioned epoxy resin in the above-mentioned chip pasting film (adhesive layer) 3 is preferably in the range of 5 mass % to 60 mass %, and more preferably in the range of 10 mass % to 50 mass %.

[0192] (Curing agent for epoxy resin)

[0193] As a curing agent for epoxy resin, for example, a phenolic resin obtained by reacting a phenol compound with a xylene compound as a divalent linking group in the absence of a catalyst or an acid catalyst can be cited. As the above-mentioned phenolic resin, for example, polyoxystyrene such as novolac type phenolic resin, resol type phenolic resin and polyoxystyrene can be cited. As a novolac type phenolic resin, for example, phenol novolac resin, phenol aralkyl resin, cresol novolac resin, tert-butylphenol novolac resin and nonylphenol novolac resin can be cited. These phenolic resins can be used alone, or two or more combinations can be used. Among these phenolic resins, phenol novolac resin and phenol aralkyl resin have a tendency to improve the connection reliability of chip pasting film (adhesive layer) 3, so they are suitable for use.

[0194] From the viewpoint of allowing the curing reaction of the epoxy resin and the phenolic resin in the above-mentioned thermosetting resin composition to proceed sufficiently, the phenolic resin is preferably blended in the following amount: relative to 1 equivalent of epoxy group in the epoxy resin component, the hydroxyl group in the phenolic resin is preferably in the range of 0.5 equivalents to 2.0 equivalents, and more preferably in the range of 0.8 equivalents to 1.2 equivalents.

[0195] (other)

[0196] In addition, a curing accelerator such as a tertiary amine, imidazoles, or quaternary ammonium salts may be added to the thermosetting resin composition as needed. Specific examples of such curing accelerators include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-cyanoethyl-2-phenylimidazole. Trimellitate, etc. These may be used alone or in combination of two or more.

[0197] In addition, in the above-mentioned thermosetting resin composition, from the viewpoint of controlling the fluidity of the chip pasting film (adhesive layer) 3 and improving the elastic modulus, an inorganic filler can be added as needed. Specifically, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whisker, boron nitride, crystalline silica, amorphous silica, etc. can be cited, and they can be used alone or in combination of two or more. The content ratio of the above-mentioned inorganic filler in the above-mentioned chip pasting film (adhesive layer) 3 is preferably in the range of 35 mass % to 60 mass %.

[0198] In addition, flame retardants, silane coupling agents, ion trap agents, etc. may be added to the above-mentioned thermosetting resin composition as needed. Examples of flame retardants include antimony trioxide, antimony pentoxide, and brominated epoxy resins. Examples of silane coupling agents include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane. Examples of ion trap agents include hydrotalcites, bismuth hydroxide, hydrous antimony oxide, zirconium phosphates of specific structures, magnesium silicate, aluminum silicate, triazole compounds, tetrazole compounds, and bipyridine compounds.

[0199] <Thickness of die attach film (adhesive layer)>

[0200] The thickness of the chip pasting film (adhesive layer) 3 is not particularly limited, but is preferably in the range of 5 μm to 60 μm. If the thickness of the chip pasting film (adhesive layer) 3 is less than 5 μm, the bonding strength between the semiconductor chip and the lead frame or wiring substrate may be insufficient. On the other hand, if the thickness of the chip pasting film (adhesive layer) 3 is greater than 60 μm, it is not economical and the response to the miniaturization and thin-filming of semiconductor devices is likely to be insufficient.

[0201] <Method for producing chip attach film>

[0202] The above-mentioned chip pasting film (adhesive layer) 3 is manufactured, for example, as follows. First, a release liner is prepared. It should be noted that as the release liner, the same release liner as the release liner arranged on the adhesive layer 2 of the dicing tape 10 can be used. Next, a coating solution for the chip pasting film (adhesive layer) 3, which is a forming material of the chip pasting film (adhesive layer) 3, is prepared. The coating solution can be prepared, for example, by uniformly mixing and dispersing a thermosetting resin composition containing a glycidyl (meth) acrylate copolymer, an epoxy resin, and a curing agent for the epoxy resin, which are constituent components of the chip pasting film (adhesive layer) 3, with a diluent solvent. As a solvent, a general organic solvent such as methyl ethyl ketone and cyclohexanone can be used.

[0203] Next, for the chip pasting film (adhesive layer) 3, a coating solution is applied to the release-treated surface of the above-mentioned release pad as a temporary support and dried to form a chip pasting film (adhesive layer) 3 of a predetermined thickness. Then, the release-treated surface of another release pad is bonded to the chip pasting film (adhesive layer) 3. There is no particular limitation on the coating method, and coating can be performed using, for example, a die coater, a notch wheel coater (registered trademark), a gravure coater, a roller coater, a reverse coater, etc. In addition, as drying conditions, for example, it is preferably carried out within a range of a drying temperature of 70°C to 160°C and a drying time of 1 minute to 5 minutes. It should be noted that in the present invention, a laminate having a release liner on both sides or one side of the chip pasting film (adhesive layer) 3 is sometimes also referred to as a chip pasting film (adhesive layer) 3.

[0204] <Method for producing die attach film for dicing>

[0205] There is no particular limitation on the manufacturing method of the above-mentioned chip pasting film 20 for cutting, and it can be manufactured by a conventionally known method. For example, the above-mentioned chip pasting film 20 for cutting can first prepare the cutting tape 10 and the chip pasting film 20 separately, then peel off the adhesive layer 2 of the cutting tape 10 and the release liner of the chip pasting film (adhesive layer) 3 respectively, and laminate the adhesive layer 2 of the cutting tape 10 and the chip pasting film (adhesive layer) 3 by laminating rollers such as a hot roll laminator. As the laminating temperature, it is preferably in the range of, for example, 10°C to 100°C, and as the laminating pressure (linear pressure), it is preferably in the range of, for example, 0.1kgf / cm to 100kgf / cm. It should be noted that in the present invention, with respect to the chip pasting film 20 for cutting, a laminate having a release liner on the adhesive layer 2 and the chip pasting film (adhesive layer) 3 is sometimes also referred to as the chip pasting film 20 for cutting. In the dicing die attach film 20 , the release liner provided on the pressure-sensitive adhesive layer 2 and the die attach film (adhesive layer) 3 may be peeled off when the dicing die attach film 20 is supplied to a workpiece.

[0206] The dicing die attach film 20 may be in the form of a roll or a wide sheet stack. In addition, the dicing tape 10 may be cut into a sheet or tape shape to be formed in a predetermined size.

[0207] For example, as disclosed in Japanese Patent Application Publication No. 2011-159929, it can be manufactured in the form of a film roll in which a plurality of adhesive layers (die attaching films) and adhesive films (dicing tapes) pre-cut into the shape of wafers constituting semiconductor elements are formed in an island shape on a release substrate (release liner). In this case, the dicing tape 10 is formed into a circular shape having a diameter larger than that of the die attaching film (adhesive layer) 3, and the die attaching film (adhesive layer) 3 is formed into a circular shape having a diameter larger than that of the semiconductor wafer 30.

[0208] Semiconductor chip manufacturing method

[0209] Figure 5 This is a flowchart for explaining a method for manufacturing a semiconductor chip using the dicing tape 10 or the dicing die attach film 20 of the present embodiment. Figure 6 This is a schematic diagram showing a state in which a ring frame (wafer ring) is attached to the outer edge of a dicing tape (or a dicing chip pasting film) and a semiconductor wafer is attached to the center. Furthermore, Figure 7 (a) to (f) are diagrams showing an example of manufacturing a semiconductor chip using a dicing tape having an adhesive layer 2 laminated on a base film 1 according to the present embodiment. Figure 8 (a) to (f) are views showing an example of manufacturing a semiconductor chip using the dicing die attach film 20 in which a die attach film (adhesive layer) 3 is laminated on the adhesive layer 2 of the dicing tape 10 according to the present embodiment.

[0210] <Method for Manufacturing Semiconductor Chip Using Dicing Tape 10>

[0211] First, if Figure 7 As shown in (a), a semiconductor wafer 30 having silicon as its main component and on which a plurality of integrated circuits (not shown) are mounted is prepared (step S201: preparation process).

[0212] Next, the surface of the semiconductor wafer 30 opposite to the surface on which the integrated circuit is mounted is ground to make the semiconductor wafer 30 have a predetermined thickness (step S202: grinding process). At this time, although not shown in the figure, a protective tape (back grinding tape) is attached to the surface on which the integrated circuit is mounted of the semiconductor wafer 30. The protective tape is peeled off before the cutting (dicing) process of the semiconductor wafer 30.

[0213] The thickness of the semiconductor wafer 30 is preferably adjusted to 100 μm or less, and more preferably adjusted to a thickness of 20 μm or more and 50 μm or less. Although semiconductor chips are expected to be thinner, if the thickness is reduced, they will be brittle and easily broken, and the yield rate will deteriorate. The dicing tape of the present invention can practically pick up semiconductor chips with small thickness at a push-up speed within the allowable range and at a smaller push-up height without damage.

[0214] Then, if Figure 6 and Figure 7 As shown in (a), after the release liner is peeled off from the adhesive layer 2 of the dicing tape 10 cut into a circular shape, a ring frame (wafer ring) 40 is attached to the outer edge of the adhesive layer 2 of the dicing tape 10, and a semiconductor wafer 30 is attached to the center of the adhesive layer 2 of the dicing tape 10 (step S203: attaching process). In the case where the dicing tape 10 is attached immediately after the semiconductor wafer 30 is polished in step 202, the dicing tape 10 is attached to the semiconductor wafer 30 in a state where active atoms exist on the surface of the semiconductor wafer 30.

[0215] Here, in the attaching process, the dicing tape 10 is generally attached to the semiconductor wafer 30 using a pressure roller that presses the adhesive tape. The attaching temperature is not particularly limited, and is preferably in a range of, for example, 20°C to 80°C. In addition, the pressure during attaching is not particularly limited, and is preferably in a range of, for example, 0.1 MPa to 0.3 MPa. In addition, the semiconductor wafer 30 and the dicing tape 10 may be overlapped in a pressurizable container (for example, an autoclave, etc.), and the dicing tape 10 may be attached to the semiconductor wafer 30 by pressurizing the inside of the container. Furthermore, the dicing tape 10 may be attached to the semiconductor wafer 30 in a reduced pressure chamber (vacuum chamber).

[0216] Then, if Figure 7 As shown in (b), after the dicing tape 10 and the semiconductor wafer 30 are bonded together, a dicing machine or the like is used in accordance with a conventional method to cut the semiconductor wafer 30 from the side on which the integrated circuit is mounted into a predetermined size using a dicing knife along a predetermined cutting (cutting) line X to separate the semiconductor wafer 30 into individual pieces to form semiconductor chips 30a (step S204: cutting (cutting) process). Figure 7 As shown in (c), in this example, the semiconductor wafer 30 is completely cut into the so-called full cut. In the cutting process of cutting the semiconductor wafer 30, it is ideal to only cut the semiconductor wafer 30 to obtain the semiconductor chip 30a, but in fact, considering the operation accuracy of the device, the dicing tape 10 used, and the thickness accuracy of the semiconductor wafer 30, in order to accurately obtain the semiconductor chip 30a, Figure 7 As shown in (c), it is preferred that the adhesive layer 2 and a part of the base film 1 are cut.

[0217] As described above, the substrate film 1 of the present embodiment is not likely to generate filament-like cuttings during cutting even if a portion of the substrate film 1 is cut. Therefore, it is possible to suppress poor pickup of the semiconductor chip 30a. The cutting depth of the substrate film 1 by the cutting knife is not particularly limited, but is preferably set to 1 / 2 of the thickness of the substrate film 1, and more preferably to 1 / 4 of the thickness of the substrate film 1, from the viewpoint of balancing the suppression of the generation of cuttings and the strength of the partially cut substrate film 1 (the strength of the substrate film 1 not to be broken in the expansion process described later).

[0218] Here, in the cutting process, generally, in order to remove friction heat and prevent adhesion of cutting chips, the semiconductor wafer 30 to which the dicing tape 10 is attached is supplied with cleaning water while being cut into predetermined sizes using, for example, a rotating blade.

[0219] Next, the cutting tape 10 is irradiated with active energy rays from the side of the substrate film 1, so that the adhesive layer 2 is cured and shrunk, and the adhesive force of the adhesive layer 2 is reduced (step S205: active energy ray irradiation process). Here, as active energy rays used for the above-mentioned post-irradiation, ultraviolet rays, visible rays, infrared rays, electron rays, beta rays, gamma rays, etc. can be cited. Among these active energy rays, ultraviolet rays (UV) and electron rays (EB) are preferably used, and ultraviolet rays (UV) are particularly preferably used. There is no particular limitation on the light source used for irradiating the above-mentioned ultraviolet rays (UV). For example, a black light lamp, an ultraviolet fluorescent lamp, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, etc. can be used. In addition, ArF excimer lasers, KrF excimer lasers, excimer lamps, or synchrotron radiation light can also be used. The irradiation light amount of the above-mentioned ultraviolet rays (UV) is not particularly limited. For example, it is preferably 100mJ / cm 2 Above 2000J / cm 2 The range is as follows, more preferably 300 mJ / cm 2 Above 1000J / cm 2 The following range.

[0220] It should be noted that the active energy ray irradiation process can be performed only when the adhesive layer 2 of the cutting tape 10 is composed of an active energy ray-curable adhesive composition. When the adhesive layer 2 of the cutting tape 10 is composed of an active energy ray-non-curable adhesive composition, the active energy ray irradiation process is not required.

[0221] Next, in order to easily pick up each semiconductor chip 30a formed by dicing, as shown in FIG. Figure 7As shown in (d), after the cutting process, the dicing tape 10 is stretched (expanded) (step S206: expansion process). Specifically, for the dicing tape 10 that maintains the state of the multiple semiconductor chips 30a after cutting, the hollow cylindrical push-up member is raised from the lower surface side of the dicing tape 10, and the dicing tape 10 is expanded in a radially stretched two-dimensional direction including the radial and circumferential directions of the annular frame (wafer ring) 40. Through the expansion process, the intervals between the semiconductor chips 30a can be enlarged, the recognizability of the semiconductor chips 30a based on a CCD camera or the like can be improved, and the re-adhesion of the semiconductor chips 30a caused by the contact between adjacent semiconductor chips 30a during picking up can be prevented. As a result, the pick-up performance of the semiconductor chip 30a is improved.

[0222] Next, so-called picking up is performed, that is, each semiconductor chip 30 a that has been singulated by cutting the semiconductor wafer 30 is peeled off from the dicing tape 10 (step S207 : peeling (picking up) step).

[0223] As the above-mentioned picking method, for example, the following methods can be cited: Figure 7 As shown in (e), for the semiconductor chip 30a, the second surface of the base film 1 of the dicing tape 10 is pushed up by the push-up pusher (needle-shaped object) 60, and as shown in Figure 7 As shown in (f), the semiconductor chip 30a pushed up is sucked by a suction collet 50 of a pickup device (not shown) and peeled off from the adhesive layer 2 of the dicing tape 10. In this way, the semiconductor chip 30a is obtained.

[0224] The picking condition is not particularly limited as long as it is within a range that is permissible in actual use. Usually, the pushing speed of the pushing needle 60 is mostly set within a range of 1 mm / sec to 100 mm / sec. However, when the thickness of the semiconductor chip 30a (the thickness of the semiconductor wafer) is as thin as 100 μm or less, it is preferably set within a range of 1 mm / sec to 20 mm / sec from the viewpoint of suppressing damage to the semiconductor thin film chip. From the viewpoint of taking productivity into consideration, it is more preferably set within a range of 5 mm / sec to 20 mm / sec.

[0225] In addition, the push-up height of the push-up push rod that can pick up the semiconductor chip 30a without damage can be preferably set within a range of 100 μm to 600 μm from the same point of view as above, and is more preferably set within a range of 100 μm to 450 μm from the point of view of reducing stress on the semiconductor thin film chip. From the point of view of taking productivity into consideration, it is particularly preferably set within a range of 100 μm to 350 μm. It can be said that the pick-up property of the dicing tape that can make such a push-up height smaller is excellent.

[0226] As described above, in the dicing tape 10 of the present embodiment, in the process of peeling (picking up) the semiconductor chip 30a, when the dicing tape 10 is pushed up by the push-up pin, the dicing tape 10 is easily bent. Therefore, even if the push-up height of the push-up pin is small, that is, it is pushed up with a small force, it is easy to help the peripheral ends of the semiconductor chip 30a to be peeled off from the adhesive layer 2. As a result, even when using an extremely thin semiconductor wafer 30 with a low strength of less than 100 μm, the extremely thin semiconductor chip 30a can be quickly peeled off from the adhesive layer, and the extremely thin semiconductor chip 30a can be easily picked up from the adhesive layer 2 of the dicing tape 10 without damage using a smaller force than before. As a result, the success rate of picking up the semiconductor chip 30a can be improved more than before.

[0227] It should be noted that Figure 7 The manufacturing method described in (a) to (f) is an example of a method for manufacturing a semiconductor chip 30a using the dicing tape 10, and the method of using the dicing tape 10 is not limited to the above method. That is, the dicing tape 10 of this embodiment can be used without being limited to the above method as long as it is attached to the semiconductor wafer 30 during dicing.

[0228] For example, when using the cutting tape 10 of the present embodiment, in addition to the above-mentioned blade cutting method, the method of cutting the semiconductor wafer can also utilize the following method as a method that does not generate cutting chips: a cutting line is formed while a modified layer is selectively formed by irradiating a laser onto the inside of the semiconductor wafer, and the modified layer is used as a starting point, and an expansion process is utilized at a low temperature of, for example, -15°C to allow the cracks to grow vertically, thereby cutting the semiconductor wafer.

[0229] <Method for manufacturing semiconductor chip using die attach film 20 for dicing>

[0230] The method for manufacturing a semiconductor chip 30a when the dicing tape 10 of the present embodiment is used as a form of a dicing die attach film 20 is also described. The method for manufacturing a semiconductor chip using the dicing tape 10 is basically the same as the method for manufacturing a semiconductor chip using the dicing tape 10 described above, except that a die attach film (adhesive layer) 3 is present between the adhesive layer 2 of the dicing tape 10 and the semiconductor wafer 30. When the dicing die attach film 20 is used, the semiconductor chip 30a is picked up in a state where the die attach film (adhesive layer) 3 is attached to the surface opposite to the surface on which the integrated circuit is mounted, that is, in the form of a semiconductor chip with an adhesive layer.

[0231] First, the semiconductor wafer 30 prepared in the same manner as the method for manufacturing a semiconductor chip using the dicing tape 10 is ground to a predetermined thickness (step S201: preparation step, step S202: grinding step). Next, the release liner is peeled off from the adhesive layer 2 of the dicing die attaching film 20 cut into a circular shape and the die attaching film (adhesive layer) 3, as shown in FIG. Figure 6 and Figure 8 As shown in (a), an annular frame (wafer ring) 40 is attached to the outer edge of the adhesive layer 2 of the dicing tape 10, and a semiconductor wafer 30 is attached to the chip pasting film (adhesive layer) 3 stacked on the upper center portion of the adhesive layer 2 of the dicing tape 10 (step S203: attaching process).

[0232] Then, if Figure 8 As shown in (b), in a state where the dicing die attaching film 20 is attached to the semiconductor wafer 30, the semiconductor wafer 30 is cut into a predetermined size along a predetermined cutting (cutting) line X from one side on which the integrated circuit is mounted, using a dicing machine or the like, in accordance with a conventional method, to form individual pieces of semiconductor chips 30a (step S204: cutting (cutting) process). Figure 8 As shown in (c), in this example, the semiconductor wafer 30 is completely cut into the so-called full cut. In the cutting process of cutting the semiconductor wafer 30, it is ideal to only cut the semiconductor wafer 30 in order to obtain the semiconductor chip 30a, but in fact, considering the operation accuracy of the device, the dicing tape 10 used, and the thickness accuracy of the semiconductor wafer 30, in order to accurately obtain the semiconductor chip 30a, Figure 8 As shown in (c), it is preferred that the die attach film (adhesive layer) 3, the adhesive layer 2, and a part of the base film 1 are cut.

[0233] There is no particular limitation on the cutting depth of the blade into the substrate film 1. From the perspective of balancing the suppression of chip generation and the strength of the partially cut substrate film 1 (the strength at which the substrate film 1 does not break in the expansion process described later), it is preferably set to 1 / 2 of the thickness of the substrate film 1, and more preferably to 1 / 4 of the thickness of the substrate film 1.

[0234] Next, similarly to the method for manufacturing a semiconductor chip using the dicing tape 10, step S205: an active energy ray irradiation step is performed as necessary, and then step S206: an expansion step (see Figure 8 (d)), then go through step S207: peeling (picking up) process (refer to Figure 8 (e) Figure 8 (f)), even when using an extremely thin semiconductor wafer 30 of 100 μm or less having low strength, the extremely thin semiconductor chip 30a with the die attach film (adhesive layer) 3 can be easily picked up from the adhesive layer 2 of the dicing die attach film 20.

[0235] It should be noted that Figure 8 The manufacturing method described in (a) to (f) is an example of a method for manufacturing a semiconductor chip 30a using the dicing die attach film 20, and the method of using the dicing tape 10 as the form of the dicing die attach film 20 is not limited to the above method. That is, the dicing die attach film 20 of the present embodiment can be used without being limited to the above method as long as it is attached to the semiconductor wafer 30 during dicing.

[0236] For example, when the dicing tape 10 of the present embodiment is used as a form of a chip pasting film 20 for dicing, the method for dicing the semiconductor wafer can be used, in addition to the above-mentioned blade dicing method, as a method that does not generate cutting chips, by using the following method, etc.: a cutting line is formed while a modified layer is selectively formed by irradiating a laser onto the inside of the semiconductor wafer, and the modified layer is used as a starting point, and an expansion process at a low temperature of, for example, -15°C is used to make the crack grow vertically, thereby cutting the semiconductor wafer together with the chip pasting film.

[0237] [Example]

[0238] Next, the present invention will be described in more detail using examples and comparative examples. It should be noted that the present invention is not limited to the following examples.

[0239] 1. Preparation of substrate film 1

[0240] The following resins A to I were prepared as materials for preparing the substrate film 1. It should be noted that resins A to G are thermoplastic polyester elastomers produced using dimethyl terephthalate and 1,4-butanediol as hard segment (PBT) components, and poly(oxytetramethylene) glycol (PTMG1000) having a number average molecular weight of 1,000, poly(oxytetramethylene) glycol (PTMG1500) having a number average molecular weight of 1,500, or poly(oxytetramethylene) glycol (PTMG2000) having a number average molecular weight of 2,000 as soft segment components.

[0241] (resin)

[0242] Resin A: A thermoplastic polyester elastomer composed of a segment ratio of polybutylene terephthalate (PBT) / poly(oxytetramethylene) glycol (PTMG2000) = 27 mass% / 73 mass%, with a crystalline melting point of 160°C

[0243] Resin B: A thermoplastic polyester elastomer composed of a segment ratio of polybutylene terephthalate (PBT) / poly(oxytetramethylene) glycol (PTMG2000) = 33% by mass / 67% by mass, with a crystalline melting point of 180°C

[0244] Resin C: A thermoplastic polyester elastomer composed of a segment ratio of polybutylene terephthalate (PBT) / poly(oxytetramethylene) glycol (PTMG1000) = 39 mass% / 61 mass%, with a crystalline melting point of 172°C

[0245] Resin D: A thermoplastic polyester elastomer composed of a segment ratio of polybutylene terephthalate (PBT) / poly(oxytetramethylene) glycol (PTMG1500) = 45% by mass / 55% by mass, with a crystalline melting point of 186°C

[0246] Resin E: A thermoplastic polyester elastomer composed of a segment ratio of polybutylene terephthalate (PBT) / poly(oxytetramethylene) glycol (PTMG1500) = 51% by mass / 49% by mass, with a crystalline melting point of 192°C

[0247] Resin F: A thermoplastic polyester elastomer composed of a segment ratio of polybutylene terephthalate (PBT) / poly(oxytetramethylene) glycol (PTMG1500) = 54 mass% / 46 mass%, with a crystalline melting point of 198°C

[0248] Resin G: A thermoplastic polyester elastomer composed of a segment ratio of polybutylene terephthalate (PBT) / poly(oxytetramethylene) glycol (PTMG1000) = 64 mass% / 36 mass%, with a crystalline melting point of 203°C

[0249] Resin H: Random copolymer polypropylene (PP), crystal melting point 138°C

[0250] Resin I: Ethylene-vinyl acetate copolymer (EVA), vinyl acetate content 20% by mass, crystalline melting point 82°C

[0251] Resin J: Low-density polyethylene (LDPE), crystal melting point 116°C

[0252] [Crystal melting point of resin]

[0253] The crystal melting point of the above resins was measured using a differential scanning calorimeter "DSC-8321" (product name) manufactured by Rigaku Corporation as follows. First, 10 mg of each resin sample was filled into an aluminum pan, and the temperature was raised to 290°C at a heating rate of 10°C / min in a nitrogen atmosphere. After the temperature was kept at the same temperature for 3 minutes, the aluminum pan was plunged into liquid nitrogen for rapid cooling. Next, the rapidly cooled aluminum pan was placed in the above differential scanning calorimeter "DSC-8321" again, and the peak temperature of the endothermic peak that appeared when the temperature was raised at a heating rate of 10°C / min was set as the crystal melting point of the corresponding resin.

[0254] (Base film 1 (a))

[0255] The resin B (PBT / PTMG2000=33 mass % / 67 mass %) was used to produce a substrate film 1 (a) having a single layer structure and a thickness of 100 μm using a T-die extruder.

[0256] (Base film 1 (b))

[0257] The resin C (PBT / PTMG1000=39 mass % / 61 mass %) was used to produce a substrate film 1 (b) having a single layer structure and a thickness of 100 μm by using a T-die extruder.

[0258] (Base film 1(c))

[0259] The resin D (PBT / PTMG1500=45 mass % / 55 mass %) was used to produce a substrate film 1 (c) having a single layer structure and a thickness of 100 μm by using a T-die extruder.

[0260] (Base film 1(d))

[0261] The above resin A (PBT / PTMG2000=27 mass% / 73 mass%) was used to form a 100 μm thick substrate film 1 (d) composed of three layers of the same resin using a three-layer T-die co-extrusion molding machine. The thickness of each layer was set to 1st layer (the side in contact with the adhesive layer) / 2nd layer / 3rd layer = 20 μm / 60 μm / 20 μm.

[0262] (Base film 1 (e))

[0263] Using the above-mentioned resin A (PBT / PTMG2000=27 mass% / 73 mass%) as the resin of the second layer, and the above-mentioned resin B (PBT / PTMG2000=33 mass% / 67 mass%) as the resin of the first layer and the third layer, a substrate film 1 (e) with a thickness of 100 μm consisting of three layers of two kinds of resins was prepared by using two kinds of three-layer T-die co-extrusion molding machines. The thickness of each layer is set to the first layer (the side in contact with the adhesive layer) / the second layer / the third layer=25 μm / 50 μm / 25 μm. The mass ratio of the chain segments of PBT and PTMG as the whole layer is PBT / PTMG=30 mass% / 70 mass%.

[0264] (Base film 1(f))

[0265] Using the above resin C (PBT / PTMG1000=39 mass% / 61 mass%) as the resin of the second layer, and the above resin D (PBT / PTMG1500=45 mass% / 55 mass%) as the resin of the first layer and the third layer, a substrate film 1 (f) with a thickness of 100 μm consisting of three layers of two kinds of resins was prepared by a two-layer three-layer T-die co-extrusion molding machine. The thickness of each layer was set to the first layer (the side in contact with the adhesive layer) / the second layer / the third layer=30 μm / 40 μm / 30 μm. The mass ratio of the chain segments of PBT and PTMG as the whole layer was PBT / PTMG=43 mass% / 57 mass%.

[0266] (Base film 1(g))

[0267] Using the resin E (PBT / PTMG1500=51% by mass / 49% by mass) as the resin of the first layer and the resin D (PBT / PTMG1500=45% by mass / 55% by mass) as the resin of the second layer, a substrate film 1 (g) with a thickness of 100 μm consisting of two layers of two kinds of resins was prepared by two kinds of two-layer T-die co-extrusion molding machines. The thickness of each layer was set to the first layer (the side in contact with the adhesive layer) / the second layer=30 μm / 70 μm. The mass ratio of the chain segments of PBT and PTMG as the whole layer was PBT / PTMG=47% by mass / 53% by mass.

[0268] (Base film 1(h))

[0269] Using the resin E (PBT / PTMG1500=51% by mass / 49% by mass) as the resin of the first layer and the resin D (PBT / PTMG1500=45% by mass / 55% by mass) as the resin of the second layer, a substrate film 1 (h) with a thickness of 100 μm consisting of two layers of two kinds of resins was prepared by two 2-layer T-die co-extrusion molding machines. The thickness of each layer was set to 1st layer (the side in contact with the adhesive layer) / 2nd layer=60μm / 40μm. The mass ratio of the chain segments of PBT and PTMG as the whole layer was PBT / PTMG=49% by mass / 51% by mass.

[0270] (Base film 1 (i))

[0271] The above resin A (PBT / PTMG2000=27 mass% / 73 mass%) was used to form a 155 μm thick substrate film 1 (i) composed of three layers of the same resin using a three-layer T-die co-extrusion molding machine. The thickness of each layer was set to 1st layer (the side in contact with the adhesive layer) / 2nd layer / 3rd layer = 20 μm / 115 μm / 20 μm.

[0272] (Base film 1(j))

[0273] The resin C (PBT / PTMG1000=39% by mass / 61% by mass) is used as the resin of the second layer, and the resin D (PBT / PTMG1500=45% by mass / 55% by mass) is used as the resin of the first layer and the third layer, and a substrate film 1 (j) with a thickness of 70 μm consisting of three layers of two kinds of resins is formed by a two-layer three-layer T-die co-extrusion molding machine. The thickness of each layer is set to the first layer (the side in contact with the adhesive layer) / the second layer / the third layer=20μm / 30μm / 20μm. The mass ratio of the chain segments of PBT and PTMG as the whole layer is PBT / PTMG=42% by mass / 58% by mass.

[0274] (Base film 1(k))

[0275] Using the above-mentioned resin I (EVA) as the resin of the second layer, and the above-mentioned resin H (PP) as the resin of the first layer and the third layer, a substrate film 1 (k) with a thickness of 80 μm consisting of three layers of two kinds of resins is formed by two kinds of three-layer T-die co-extrusion molding machines. The thickness of each layer is set to the first layer (the side in contact with the adhesive layer) / the second layer / the third layer = 8 μm / 64 μm / 8 μm. The mass ratio of PP / EVA as the whole layer is PP / EVA = 20 mass% / 80 mass%.

[0276] (Base film 1 (l))

[0277] The resin H (PP) is used as the resin of the second layer, and the resin J (PE) is used as the resin of the first layer and the third layer, and a substrate film 1 (l) with a thickness of 90 μm consisting of three layers of two kinds of resins is formed by two kinds of three-layer T-die co-extrusion molding machines. The thickness of each layer is set to the first layer (the side in contact with the adhesive layer) / the second layer / the third layer = 10 μm / 70 μm / 10 μm. The mass ratio of PE / PP as the whole layer is PE / PP = 22 mass% / 78 mass%.

[0278] (Base film 1(m))

[0279] The resin F (PBT / PTMG1500=54 mass % / 46 mass %) was used to produce a substrate film 1 (m) having a single layer structure and a thickness of 100 μm using a T-die extruder.

[0280] (Base film 1(n))

[0281] The resin G (PBT / PTMG1000=64 mass % / 36 mass %) was used to produce a substrate film 1 (n) having a single layer structure and a thickness of 100 μm using a T-die extruder.

[0282] [Flexural elastic modulus of substrate film (G')]

[0283] For the above-mentioned substrate films 1 (a) to (n), the flexural modulus (G') at 23°C was measured as follows using a dynamic viscoelasticity measuring device "DMA6100" (product name) manufactured by Hitachi High-Tech Science Co., Ltd. First, as a sample for measurement, a plurality of samples of the following sample sizes are cut out from a roll of substrate film 1, and a laminate is prepared by overlapping and pressing them tightly together using a hot press in such a way that the total thickness becomes 1.5 mm. The sample size is set to 10 mm (width) × 50 mm (length) × 1.5 mm (thickness). Here, the plurality of samples of substrate film 1 prepared in advance are respectively used, and are cut out from a position corresponding to the central part in the width direction when the substrate film 1 is processed into a roll of a cut tape 10 in such a way that the width direction of 10 mm in the above-mentioned sample size coincides with the MD direction (flow direction) when the substrate film 1 is formed, and the length direction of 50 mm in the above-mentioned sample size coincides with the TD direction (direction perpendicular to the MD direction) when the substrate film 1 is formed. The samples for measurement were placed in a dynamic viscoelasticity measuring apparatus, and the dynamic viscoelasticity was measured using a clamped-beam bending mode at a frequency of 1 Hz, a heating rate of 0.5°C / min, a measurement temperature range of -40°C to 40°C, and a nitrogen atmosphere. The storage modulus value at 23°C in the obtained dynamic viscoelastic spectrum was set as the bending modulus (G') of the substrate film 1.

[0284] [Ultraviolet transmittance of base film]

[0285] The ultraviolet (UV) transmittance of the substrate films 1 (a) to (n) was measured using a spectrophotometer "V-670DS" (product name) manufactured by JASCO Corporation. Specifically, the parallel light transmittance at a wavelength of 365 nm was measured.

[0286] [Elongation of base film]

[0287] The elongation of the substrate films 1 (a) to (n) in the MD and TD directions was measured using a tensile tester "Minebea TechnoGraph TG-5kN" (product name) manufactured by MinebeaMitsumi Co., Ltd. according to the method specified in JIS Z 0237 (2009).

[0288] 2. Preparation of adhesive composition solution

[0289] As the adhesive composition for the adhesive layer 2 of the dicing tape 10 , solutions of the following active energy ray non-curable acrylic adhesive compositions (a) and (b) and active energy ray curable acrylic adhesive compositions (c) and (d) were prepared.

[0290] (Solution of Adhesive Composition 2(a))

[0291] As comonomer components, methyl methacrylate (MMA), 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), and acrylic acid (AA) were prepared. These comonomer components were mixed at a copolymerization ratio of MMA / 2-EHA / 2-HEA / AA=56 mass % / 39 mass % / 3 mass % / 2 mass %, and solution free radical polymerization was performed using ethyl acetate as a solvent and azobisisobutyronitrile (AIBN) as an initiator to synthesize a base polymer solution (A) having a hydroxyl group and an acid group (solid content concentration: 35 mass %, weight average molecular weight Mw: 410,000).

[0292] Next, 0.3 parts by mass (0.3 parts by mass) of an epoxy crosslinking agent manufactured by Mitsubishi Gas Chemical Co., Ltd. (trade name: TETRAD-X, solid content concentration: 100% by mass) was added to 286 parts by mass (100 parts by mass as solid content) of the base polymer solution (A) synthesized above, and the mixture was diluted with ethyl acetate and stirred to prepare a solution of an active energy ray non-curable acrylic adhesive composition 2 (a) having a solid content concentration of 22.6% by mass.

[0293] (Solution of Adhesive Composition 2(b))

[0294] The base polymer solution (A) used in the solution of the above-mentioned adhesive composition 2 (a) is used. An isocyanate crosslinking agent (trade name: Coronate L, solid content concentration: 75% by mass) manufactured by Tosoh Corporation is added as a crosslinking agent at a ratio of 2.7 parts by mass (2.0 parts by mass in terms of solid content) to 286 parts by mass of the base polymer solution (A) (100 parts by mass in terms of solid content), and the mixture is diluted with ethyl acetate and stirred to prepare a solution of an active energy ray non-curable acrylic adhesive composition 2 (b) having a solid content concentration of 22.6% by mass.

[0295] (Adhesive composition 2(c))

[0296] As comonomer components, 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), and methyl methacrylate (MMA) were prepared. These comonomer components were mixed at a copolymerization ratio of 2-EHA / 2-HEA / MMA=75 mass % / 20 mass % / 5 mass %, and solution free radical polymerization was performed using ethyl acetate as a solvent and azobisisobutyronitrile (AIBN) as an initiator to synthesize a base polymer solution having a hydroxyl group.

[0297] Next, 16 parts by mass of 2-isocyanate ethyl methacrylate (MOI) having an isocyanate group and an active energy ray-reactive carbon-carbon double bond as an active energy ray-reactive compound was added to 100 parts by mass of the solid content of the base polymer, and reacted with a part of the hydroxyl groups of 2-HEA to synthesize an acrylic adhesive polymer solution (C) having a carbon-carbon double bond in the side chain (solid content concentration: 35% by mass, weight average molecular weight Mw: 550,000, carbon-carbon double bond content: 0.89 meq / g). It should be noted that in the above reaction, 0.05 parts by mass of hydroquinone-monomethyl ether was used as a polymerization inhibitor.

[0298] Next, with respect to 286 parts by mass (100 parts by mass in terms of solid content) of the above-synthesized acrylic adhesive polymer solution (C), 0.7 parts by mass of an acylphosphine oxide-based photopolymerization initiator (trade name: Omnirad 819) manufactured by IGM Resins BV as a photopolymerization initiator and 5.3 parts by mass (4.0 parts by mass in terms of solid content) of an isocyanate crosslinking agent (trade name: Coronate L, solid content concentration: 75% by mass) manufactured by Tosoh Corporation as a crosslinking agent were added in the following ratios, and the mixture was diluted with ethyl acetate and stirred to prepare a solution of an active energy ray-curable acrylic adhesive composition 2 (c) having a solid content concentration of 22.6% by mass.

[0299] (Adhesive composition 2(d))

[0300] As comonomer components, 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), methyl methacrylate (MMA), and N-vinyl-2-pyrrolidone (NVP) were prepared. These comonomer components were mixed at a copolymerization ratio of 2-EHA / 2-HEA / MMA / NVP=50 mass % / 3 mass % / 37 mass % / 10 mass %, and solution free radical polymerization was performed using ethyl acetate as a solvent and azobisisobutyronitrile (AIBN) as an initiator to synthesize a base polymer solution (D) having a hydroxyl group (solid content concentration: 35 mass %, weight average molecular weight Mw: 500,000).

[0301] Next, 120 parts by mass of an ultraviolet-curable urethane acrylate oligomer (weight average molecular weight Mw: 1,000, hydroxyl value: 1 mgKOH / g, double bond equivalent: 167), 1.0 parts by mass of an α-aminoalkylphenone photopolymerization initiator (trade name: Omnirad 369) manufactured by IGM Resins BV as a photopolymerization initiator, and 10 parts by mass of an isocyanate crosslinking agent (trade name: Coronate L, solid content concentration: 75% by mass) manufactured by Tosoh Corporation as a crosslinking agent were mixed at the following ratios (7.5 parts by mass in terms of solid content) with respect to 286 parts by mass of the base polymer solution (D) synthesized above (100 parts by mass in terms of solid content), and the mixture was diluted with ethyl acetate and stirred to prepare a solution of an active energy ray-curable acrylic adhesive composition 2 (d) having a solid content concentration of 22.6% by mass.

[0302] 3. Preparation of Adhesive Composition Solution

[0303] As an adhesive composition for the die attach film (adhesive layer) 3 of the dicing die attach film 20, a solution of the following adhesive composition 3 (a) was prepared.

[0304] (Solution of Adhesive Composition 3(a))

[0305] First, 55 parts by mass of a cresol novolac epoxy resin (trade name: YDCN-703, epoxy equivalent: 210, molecular weight: 1,200, softening point: 80° C.) manufactured by Tohto Kasei Co., Ltd. as a thermosetting resin, 45 parts by mass of a phenolic resin (trade name: MILEX XLC-LL, hydroxyl equivalent: 175, water absorption: 1.8%) manufactured by Mitsui Chemicals, Inc. as a crosslinking agent, 1.7 parts by mass of γ-mercaptopropyltrimethoxysilane (trade name: NUC A-189) manufactured by UNICAR Co., Ltd. and 3.2 parts by mass of γ-ureidopropyltriethoxysilane (trade name: NUCA-1160) manufactured by UNICAR Co., Ltd. as a silane coupling agent, and silica (trade name: AEROSIL To a resin composition consisting of 32 parts by mass of R972 (average particle size: 0.016 μm), cyclohexanone as a solvent was added, the mixture was stirred and mixed, and further dispersed for 90 minutes using a bead mill.

[0306] Next, 280 parts by mass of a glycidyl (meth)acrylate copolymer (trade name: HTR-860P-3, (meth)acrylate glycidyl content: 3% by mass, weight average molecular weight Mw: 800,000) manufactured by Nagase Chemicals Co., Ltd. as a thermoplastic resin and 0.5 parts by mass of 1-cyanoethyl-2-phenylimidazole (trade name: CUREZOL2PZ-CN) manufactured by Shikoku Chemicals Co., Ltd. as a curing accelerator were added to the above-mentioned resin composition, and the mixture was stirred and mixed and vacuum-released to prepare a solution of an adhesive resin composition 3(a) having a solid content concentration of 20% by mass.

[0307] <Cutting tape 10>

[0308] (Example 1)

[0309] Using the above-mentioned base film 1 (a) as the base film 1 and a solution of the adhesive composition 2 (a) as the solution of the adhesive composition for forming the adhesive layer 2, a roll (300 mm wide) of a dicing tape 10 (a) was prepared by the following steps.

[0310] On the release-treated side of the release liner (38 μm thick, polyethylene terephthalate film), a solution of the above-mentioned adhesive composition 2 (a) is applied in such a way that the thickness of the adhesive layer 2 after drying becomes 30 μm, and after heating at a temperature of 100°C for 3 minutes to dry the solvent, the base film 1 (a) is laminated on the adhesive layer 2 to prepare a roll of the dicing tape 10 (a). Then, the roll of the dicing tape 10 (a) is stored at a temperature of 40°C for 72 hours to crosslink and cure the adhesive layer 2. The roll of the dicing tape 10 (a) of this embodiment is prepared by the above steps. It should be noted that when preparing a sample for cutting a semiconductor wafer 30 with a diameter of 8 inches described later, the dicing tape 10 (a) having the release liner prepared above is cut into a circle with a diameter of 290 mm for use together with the release liner.

[0311] (Examples 2 to 13)

[0312] With respect to Example 1, as shown in Table 1, the type of the base film 1, the type of the adhesive composition for forming the adhesive layer 2, and the thickness of the adhesive layer 2 were appropriately changed. Otherwise, the same operation as in Example 1 was performed to prepare the rolls of the dicing tapes 10 (b) to (m). It should be noted that, when the base film 1 is a laminated structure, the surface of the first layer side of the base film 1 is bonded to the adhesive layer 2.

[0313] (Comparative Examples 1 to 4)

[0314] With respect to Example 12, as shown in Table 1, the type of the base film 1, the type of the adhesive composition for forming the adhesive layer 2, and the thickness of the adhesive layer 2 were appropriately changed. The same operation as in Example 12 was performed to prepare the rolls of dicing tapes 10 (n) to (q). It should be noted that when the base film 1 is a laminated structure, the surface on the first layer side of the base film 1 is attached to the adhesive layer 2.

[0315] <Dicing die attach film 20>

[0316] (Example 14)

[0317] First, a roll of a dicing tape 10 was prepared in the same manner as in Example 1 using the substrate film 1 (d) as the substrate film 1 and a solution of the adhesive composition 2 (c) as a solution of the adhesive composition for forming the adhesive layer 2 .

[0318] Next, a solution of an adhesive resin composition 3(a) for forming a chip pasting film (adhesive layer) 3 is prepared, and the solution of the adhesive resin composition 3(a) is applied to the release-treated surface of a release liner (polyethylene terephthalate film with a thickness of 38 μm) so that the thickness of the chip pasting film (adhesive layer) 3 after drying becomes 25 μm. The solution is heated at 140°C for 5 minutes to dry the solvent, thereby producing a chip pasting film (adhesive layer) 3 with a release liner.

[0319] Next, the prepared chip pasting film (adhesive layer) 3 with a release liner was cut into a circle with a diameter of 220 mm together with the release liner, and the adhesive layer surface of the chip pasting film (adhesive layer) 3 was laminated to the adhesive layer 2 surface of the dicing tape 10 from which the release liner was peeled. The laminating conditions were set to 40°C, 10 mm / sec, and a linear pressure of 30 kgf / cm.

[0320] Finally, the dicing tape 10 is cut into a circle with a diameter of 290 mm, and a dicing chip pasting film 20 (a) is prepared in which a circular chip pasting film (adhesive layer) 3 with a diameter of 220 mm is stacked on the upper center of the adhesive layer 2 of the circular dicing piece 10 with a diameter of 290 mm.

[0321] (Examples 15 to 19)

[0322] Dicing die attach films 20 (b) to (f) were prepared in the same manner as in Example 14 except that the type of substrate film 1, the type of adhesive composition for forming adhesive layer 2, and the thickness of adhesive layer 2 were appropriately changed as shown in Table 1. It should be noted that when the substrate film 1 is a laminated structure, the surface of the substrate film 1 on the first layer side is attached to the adhesive layer 2.

[0323] (Comparative Examples 5 to 8)

[0324] As shown in Table 1, the same operation as in Example 14 was performed to prepare dicing die attach films 20 (g) to (j) except that the type of the base film 1 was changed. When the base film 1 was a laminated structure, the first layer side of the base film 1 was attached to the adhesive layer 2.

[0325] 4. Evaluation method of dicing tape and dicing die attach film

[0326] For the dicing tape 10 produced in the above-mentioned Examples 1 to 13 and Comparative Examples 1 to 4, and the dicing chip pasting film 20 produced in Examples 14 to 19 and Comparative Examples 5 to 9, the splitting properties of the semiconductor wafer 30 after dicing, the cutting chip generation state of the base film, i.e., the dicing characteristics, and the pickup properties of the semiconductor chip 30a were measured and evaluated as follows.

[0327] 4.1 Separability of Semiconductor Wafers after Cutting

[0328] First, a backgrinding protective tape was bonded to the surface of a semiconductor wafer having a diameter of 8 inches using a backgrinding device "DAG-810" (product name) manufactured by DISCO Corporation, and then polished to obtain a semiconductor wafer (mirror wafer) 30 having a thickness of 50 μm.

[0329] For the dicing tapes 10 (a) to (q) of Examples 1 to 13 and Comparative Examples 1 to 4 cut into a circular shape with a diameter of 290 mm, the adhesive layer 2 surface of the dicing tape 10 from which the release liner was peeled off was attached to the surface (grinding surface side) of the semiconductor wafer 30 with a thickness of 50 μm, and a ring frame 40 was attached to the outer periphery of the adhesive layer 2 surface of the dicing tape 10 to produce Figure 7 The dicing samples shown in (a) are shown in FIG. 1. In this case, the back grinding protective tape of the semiconductor wafer 30 has been peeled off.

[0330] In addition, for the dicing chip pasting film 20 (a) to (j) in which a circular chip pasting film (adhesive layer) 3 with a diameter of 220 mm is stacked on the upper center portion of the adhesive layer 2 of the circular dicing piece 10 with a diameter of 290 mm, the chip pasting film (adhesive layer) 3 surface of the dicing chip pasting film 20 with the release liner peeled off is adhered to the surface of the semiconductor wafer 30 with a thickness of 50 μm at a hot plate temperature of 70°C, and an annular frame 40 is attached to the outer periphery of the adhesive layer 2 surface of the dicing tape 10 portion of the dicing chip pasting film 20 to produce Figure 8 The dicing samples shown in (a) are shown in FIG. 1. In this case, the back grinding protective tape of the semiconductor wafer 30 has been peeled off.

[0331] Next, the sample for cutting was cut by full-cutting method using a fully automatic dicing machine "DFD-6361" (product name) manufactured by DISCO Corporation. The cutting conditions were blade rotation speed 40,000 rpm, cutting speed 50 mm / sec, chip size 5 mm×5 mm, as shown in FIG. Figure 7 (c) and Figure 8 As shown in (c), the substrate film 1 is cut to a depth of about 5 μm. In the above-mentioned dicing step, running water is continuously supplied to the rotating blade and the semiconductor wafer for cooling (water supply amount: 1 liter / minute, water temperature: 25° C.).

[0332] After dicing the semiconductor wafer 30 using the dicing tape 10 produced in the above-mentioned Examples 1 to 13 and Comparative Examples 1 to 4, and the dicing die attach film 20 produced in Examples 14 to 19 and Comparative Examples 5 to 9, the four sides of the cut semiconductor chips 30a were observed from the surface of the semiconductor wafer 30 using an optical microscope "VHX-1000" (product name) manufactured by KEYENCE Corporation, and the division state of the semiconductor wafer 30 was evaluated based on a photograph magnified at a magnification of 150 times. Specifically, for all the semiconductor chips 30a singulated in a size of 5 mm×5 mm, it was evaluated whether they could be neatly and independently divided without cracking.

[0333] The divisibility of the semiconductor wafer after dicing was evaluated according to the following criteria: An evaluation of A was considered acceptable.

[0334] A: All chips are independent and without cracks (cuts are formed)

[0335] C: There are cracked chips, or there are chips where the cuts are not sufficiently formed and adjacent chips are in contact with each other.

[0336] 4.2 State of chip generation of substrate film after semiconductor wafer dicing

[0337] After the semiconductor wafer 30 was diced using the dicing tape 10 produced in the above-mentioned Examples 1 to 13 and Comparative Examples 1 to 4, and the dicing die attaching film 20 produced in Examples 14 to 19 and Comparative Examples 5 to 9, the degree of adhesion of the shavings at the predetermined five locations on the surface of the semiconductor wafer 30 was observed based on a photograph magnified at a magnification of 150 times using an optical microscope "VHX-1000" (product name) manufactured by KEYENCE Corporation. Specifically, for each of the predetermined five locations on the semiconductor wafer that has undergone the dicing process, the number of shavings in the form of shavings with a length of 50 μm or more was counted, and the total number of shavings in the form of shavings at these five locations was divided by 5 (average number of roots) to calculate. The above-mentioned predetermined five positions refer to the intersection positions of the dividing grooves (cutting lines) formed by cutting, including a cross line portion (central portion) of the intersection position closest to the center of the semiconductor wafer, and cross line portions of four intersection positions (upper, lower, left and right portions) located in the layer in contact with the adhesive layer and isolated from each other at 90 degree intervals in the circumferential direction of the semiconductor wafer.

[0338] The state of generation of cutting chips of the base film after dicing of the semiconductor wafer was evaluated according to the following criteria: An evaluation of A or B was considered as a pass.

[0339] A: The average number of wire-like chips is 0 or more and less than 1

[0340] B: The average number of wire-like chips is 1 or more and less than 10

[0341] C: The average number of wire-like chips is 10 or more

[0342] 4.3 Evaluation of Pickup Performance of Semiconductor Chips

[0343] After the semiconductor wafer 30 was diced using the dicing tapes 10 prepared in the above-mentioned Examples 1 to 13 and Comparative Examples 1 to 4, and the dicing die attaching films 20 prepared in the Examples 14 to 19 and Comparative Examples 5 to 9, each dicing tape 10 and each dicing die attaching film 20 were expanded to increase the distance between the semiconductor chips 30a. It should be noted that, when an active energy ray-curable acrylic adhesive composition was used as the adhesive composition of the adhesive layer 2, before expansion, the adhesive layer 2 was irradiated with a cumulative irradiation light amount of 300 mJ / cm from the substrate film 1 side. 2 The adhesive layer 2 is cross-linked and cured by ultraviolet rays (UV). When an active energy ray non-curing acrylic adhesive composition is used as the adhesive composition of the adhesive layer 2, expansion is performed without irradiating ultraviolet rays (UV). In the expansion process, the expansion speed (the speed at which the hollow cylindrical push-up member rises) is set to 30 mm / sec, and the expansion amount (the distance the hollow cylindrical push-up member rises) is set to 9 mm.

[0344] For the semiconductor chip 30a in a state where the distance between the semiconductor chips 30a singulated on the dicing tape 10 and the dicing chip adhesive film 20 is enlarged through the above-mentioned expansion process, a pickup test is carried out using a pickup device "WCS-700" (product name) manufactured by Daito Electronics Co., Ltd. to evaluate the pickup performance. The collet of the pickup portion used has, for example, a 4.5mm×4.5mm push-up surface, and 5 push-up pins 60 are arranged at predetermined intervals along the diagonal of the push-up surface. Regarding the picking conditions, the push-up speed is set to 5mm / second, and the push-up height is changed in the range of 350 to 500μm by 50μm. It should be noted that the picking conditions are within the range where there is no problem in actual use.

[0345] Then, at each push-up height, the number of samples of the semiconductor chips 30 a is set to 20 at a predetermined position, and the number of semiconductor chips 30 a that can be picked up without being damaged by the suction collet 50 is counted.

[0346] The pickup performance of the semiconductor chip 30 a was evaluated at each push-up height according to the following criteria.

[0347] A: The number of successful semiconductor chip pickups is 20 (success rate 100%)

[0348] B: The number of successful pickups of semiconductor chips is 18 or more and less than 20 (the success rate is 90% or more and less than 100%)

[0349] C: The number of successful semiconductor chip pickups is 16 or more and less than 18 (the success rate is 80% or more and less than 90%)

[0350] D: The number of successful pickups of semiconductor chips is less than 16 (the success rate is less than 80%)

[0351] As a comprehensive evaluation of the pickup test, the number of successful pickups of semiconductor chips is evaluated as follows: the smaller the push-up height of the push-up pin A or B is, the better the pickup property of the dicing tape 10 or the dicing die attach film 20 is.

[0352] 5. Evaluation results

[0353] The evaluation results of the dicing tapes 10 produced in Examples 1 to 13 and Comparative Examples 1 to 4, and the dicing die pasting films 20 produced in Examples 14 to 19 and Comparative Examples 5 to 9 are shown in Tables 1 to 7 in combination with the structures of the dicing tapes 10 and the dicing die pasting films 20 and the structure of the base film 1 used.

[0354] [Table 1]

[0355]

[0356] [Table 2]

[0357]

[0358] [Table 3]

[0359]

[0360] [Table 4]

[0361]

[0362] [Table 5]

[0363]

[0364] [Table 6]

[0365]

[0366] [Table 7]

[0367]

[0368] First, as shown in Tables 1 to 4, it was confirmed that the dicing tapes 10 (a) to (m) of Examples 1 to 13 using the base films 1 (a) to (j) satisfying the requirements of the present invention achieved preferable results in any evaluation of the dicing characteristics and the pickup properties.

[0369] When the examples are compared in detail, it can be seen that the dicing tapes 10 of Examples 1 to 3, Examples 5, 6, and Examples 10 to 13 using a base film 1 having a bending elastic modulus (G') in the range of 17 MPa to 115 MPa are superior to the dicing tapes 10 of Examples 4 and 9, Examples 7, and 8 using a base film 1 having a bending elastic modulus (G') of 10.4 MPa, 118.5 MPa, and 133.9 MPa, respectively, in terms of cutting characteristics (suppression of cutting chips) and pick-up performance (minimum push-up height at which the pick-up success rate reaches 100%), and are of high grade and can be taken into account at the same time. That is, the dicing tapes 10 of Examples 4 and 9 using a base film 1 having a bending elastic modulus (G') of 10.4 MPa are slightly inferior to the dicing tapes 10 of the other examples in terms of the effect of suppressing cutting chips during cutting. Compared with the cutting tapes 10 of other embodiments, the cutting tapes 10 of embodiments 7 and 8 using the base film 1 with the bending elastic modulus (G') of 118.5 MPa and 133.9 MPa respectively have a minimum push-up height of 400 μm for a 100% success rate in the picking-up test, which is 50 μm larger than 350 μm of the cutting tapes 10 of other embodiments, and the picking-up performance is slightly poor.

[0370] In contrast, as shown in Table 4, it was confirmed that the cutting tapes 10(n) to (q) of Comparative Examples 1 to 4 using substrate films 1(k) to (n) that do not meet the requirements of the present invention had results worse than those of the cutting tapes 10(a) to (m) of Examples 1 to 13 in at least one of the evaluations of cutting characteristics and pickup properties.

[0371] Specifically, the cutting tape 10(n) of Comparative Example 1, which uses a base film 1(k) composed of a polyolefin resin of PP / EVA / PP (two resins, three layers) having a bending elastic modulus (G') of 146.5 MPa, which exceeds the upper limit of the range of the bending elastic modulus (G') of the present invention, has good splitting properties during cutting and chip suppression effects, but in the picking-up test, the picking-up success rate did not reach 100% at any push-up height within the predetermined range, and in particular, when the push-up height reached 450 μm or more, many picking-up errors due to chip breakage were observed everywhere, and the picking-up performance was significantly deteriorated compared with the cutting tape 10 of the embodiment.

[0372] In addition, the dicing tape 10(o) of Comparative Example 2 using a substrate film 1(l) composed of a polyolefin resin of PE / PP / PE (two resins, three layers) having a flexural modulus (G') of 413.0 MPa, which exceeds the upper limit of the range of the flexural modulus (G') of the present invention, has good splitting properties during cutting, but since the crystalline melting point of the PE of the first layer (the side in contact with the adhesive layer 2) of the substrate film 1 having the first surface is low, a lot of shavings are generated and attached during cutting, and the shavings suppression effect during cutting is poor compared with the dicing tape 10 of the embodiment. Furthermore, in the pick-up test, the pick-up success rate did not reach 100% at any push-up height within the predetermined range, and many pick-up errors due to poor chip peeling or chip breakage were found everywhere, and the pick-up properties were greatly deteriorated compared with the dicing tape 10 of the embodiment.

[0373] In addition, the cutting tape 10(p) of Comparative Example 3, which uses a base film 1(m) composed of a thermoplastic polyester elastomer of a PBT / PTMG copolymer having a bending elastic modulus (G') of 159.7 MPa, which exceeds the upper limit of the range of the bending elastic modulus (G') of the present invention, has good splitting properties and chip suppression effects during cutting, but in the pickup test, has evaluation results of the same degree as those of Comparative Example 1, and the pickup property is significantly deteriorated compared with the cutting tape 10 of the embodiment.

[0374] In addition, the cutting tape 10(q) of Comparative Example 4, which uses a base film 1(n) composed of a thermoplastic polyester elastomer of a PBT / PTMG copolymer having a bending elastic modulus (G') of 218.7 MPa, which exceeds the upper limit of the range of the bending elastic modulus (G') of the present invention, has good splitting properties and chip suppression effects during cutting, but in the pickup test, has an evaluation result of the same degree as that of Comparative Example 2, and the pickup property is greatly deteriorated compared with the cutting tape 10 of the embodiment.

[0375] Next, as shown in Tables 5 to 7, for the chip pasting films 20 (a) to (f) for cutting of Examples 14 to 19 using the substrate films 1 (a), (c) to (e), and (h) that meet the requirements of the present invention, it was also confirmed that preferred results were obtained in any evaluation of the cutting characteristics and the pickup properties.

[0376] When the examples are compared in detail, it can be seen that the dicing die attach films 20 of Examples 15, 16, 18, and 19 using the base film 1 having the bending elastic modulus (G') in the range of 17 MPa to 115 MPa are superior to the dicing die attach films 20 of Examples 14 and 17 using the base film 1 having the bending elastic modulus (G') of 10.4 MPa and 133.9 MPa, respectively, in terms of both the dicing characteristics (suppression of cutting chips) and the pickup performance (the lowest push-up height at which the pickup success rate reaches 100%), which are high-level and can be achieved. That is, the dicing die attach film 20 of Example 14 using the base film 1 having the bending elastic modulus (G') of 10.4 MPa is slightly inferior to the dicing die attach films 20 of the other examples in terms of the effect of suppressing cutting chips. The cutting chip pasting film 20 of Example 17 using a base film 1 with a bending elastic modulus (G') of 133.9 MPa has a minimum push-up height of 400 μm for a 100% success rate of picking up compared to the cutting chip pasting film 20 of other examples, which is 50 μm larger than 350 μm of the cutting chip pasting film 20 of other examples, and the picking performance is slightly poor.

[0377] In contrast, as shown in Tables 6 and 7, it was confirmed that the dicing chip pasting films 20(g) to (j) of Comparative Examples 5 to 8 using substrate films 1(k) to (n) that do not meet the requirements of the present invention had results worse than those of the dicing chip pasting films 20(a) to (f) of Examples 14 to 19 in at least one of the evaluations of dicing characteristics and pickup properties.

[0378] Specifically, the chip pasting film 20(g) for cutting of Comparative Example 5, which uses a base film 1(k) composed of a polyolefin resin of PP / EVA / PP (two resins, three layers) having a bending elastic modulus (G') of 146.5 MPa, which exceeds the upper limit of the range of the bending elastic modulus (G') of the present invention, has good splitting properties during cutting and chip suppression effects, but in the picking-up test, the picking-up success rate at any push-up height within the predetermined range did not reach 100%. In particular, when the push-up height reached 450 μm, many picking-up errors due to chip breakage were observed everywhere, and the picking-up property was significantly deteriorated compared with the chip pasting film 20 for cutting of the embodiment.

[0379] In addition, the dicing die pasting film 20(h) of Comparative Example 6 using a base film 1(l) composed of a polyolefin resin of PE / PP / PE (two resins, three layers) having a flexural modulus (G') of 413.0 MPa, which exceeds the upper limit of the range of the flexural modulus (G') of the present invention, has good splitting properties during dicing, but since the crystalline melting point of PE of the first layer (the side in contact with the adhesive layer 2) of the base film 1 having the first surface is low, a lot of shavings are generated and attached during dicing, and the effect of suppressing shavings during dicing is poor compared with the dicing die pasting film 20 of the embodiment. Furthermore, in the pick-up test, the pick-up success rate did not reach 100% at any push-up height within the predetermined range, and many pick-up errors due to poor chip peeling or chip breakage were found everywhere, and the pick-up properties were greatly deteriorated compared with the dicing die pasting film 20 of the embodiment.

[0380] In addition, the dicing chip pasting film 20(i) of Comparative Example 7, which uses a base film 1(m) composed of a thermoplastic polyester elastomer of a PBT / PTMG copolymer having a flexural modulus (G') of 159.7 MPa, which exceeds the upper limit of the range of the flexural modulus (G') of the present invention, has good splitting properties and chip suppression effects during cutting, but in the pickup test, has evaluation results equivalent to those of Comparative Example 5, and the pickup properties are significantly deteriorated compared to the dicing chip pasting film 20 of the embodiment.

[0381] In addition, the dicing chip pasting film 20(q) of Comparative Example 8, which uses a base film 1(n) composed of a thermoplastic polyester elastomer of a PBT / PTMG copolymer having a flexural modulus (G') of 218.7 MPa, which exceeds the upper limit of the range of the flexural modulus (G') of the present invention, has good splitting properties during cutting and chip suppression effects, but in the pickup test, has evaluation results of the same degree as those of Comparative Example 6, and is significantly inferior to the dicing chip pasting film 20 of the embodiment.

Claims

1. A base film for a dicing tape, comprising a first surface on which an adhesive layer is formed and a second surface opposite to the first surface, The substrate film is composed of a resin containing a thermoplastic polyester elastomer, wherein the thermoplastic polyester elastomer is a block copolymer containing a hard segment (A) and a soft segment (B), wherein the hard segment (A) contains a polyester composed of an aromatic dicarboxylic acid and an aliphatic diol or an alicyclic diol as a main component, and the soft segment (B) contains an aliphatic polyether as a main component, and is characterized in that: The substrate film has a bending elastic modulus G' at 23° C. in the range of 10 MPa to 135 MPa, when the dynamic viscoelasticity is measured using a clamped-end beam bending mode at a frequency of 1 Hz and a heating rate of 0.5° C. / min. The soft segment (B) has a content, that is, a copolymerization amount, in the range of 51% by mass or more and 73% by mass or less relative to the total mass of the hard segment (A) and the soft segment (B).

2. The substrate film according to claim 1, characterized in that The base film has the bending modulus G' at 23° C. in the range of 17 MPa to 115 MPa.

3. The substrate film according to claim 1 or 2, characterized in that The soft segment (B) has a content, that is, a copolymerization amount, in the range of 55% by mass or more and 70% by mass or less relative to the total mass of the hard segment (A) and the soft segment (B).

4. The substrate film according to claim 1 or 2, characterized in that The hard segment (A) is polybutylene terephthalate, namely PBT.

5. The substrate film according to claim 1 or 2, characterized in that The soft segment (B) is poly(oxytetramethylene) glycol, ie, PTMG, and / or ethylene oxide addition polymer of poly(propylene oxide) glycol, ie, PPG-EO addition polymer.

6. The substrate film according to claim 1 or 2, characterized in that The substrate film is composed of a single resin layer, and the resin constituting the layer, which contains the thermoplastic polyester elastomer, has a crystalline melting point in the range of 160° C. to 200° C.

7. The substrate film according to claim 1 or 2, characterized in that: The substrate film is composed of a plurality of laminated resin layers, and the resin containing the thermoplastic polyester elastomer constituting the layer having the first surface has a crystalline melting point in the range of 160° C. to 200° C.

8. The substrate film according to claim 1 or 2, characterized in that: The thickness is in the range of 70 μm to 155 μm.

9. The substrate film according to claim 1 or 2, characterized in that: The elongation is in the range of 300% to 700%.

10. A cutting belt, characterized in that: The invention comprises the base film according to claim 1 or 2 and an adhesive layer formed on the surface of the base film.

Images