Adhesive tape

Abstract

To provide an adhesive tape capable of suppressing separation between a substrate and an adhesive layer caused by warpage of the substrate.SOLUTION: An adhesive tape includes a substrate, and an adhesive layer laminated on one face of the substrate to be used for temporarily fixing the substrate where the measured value satisfies 1000 mN / 25 mm or more when subjecting a test piece after pasting a test piece of a width of 25 mm and a length of 200 mm on a mirror surface of a silicon wafer to a 90 degree low speed peel test of peeling the test piece in a direction of 90 degree by a peel speed of 10 mm / min. by a method in accordance with a regulation of JIS Z 0237:2009.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an adhesive tape used for temporarily fixing substrates. [Background technology]

[0002] In the manufacturing process of semiconductor devices, adhesive tape (dicing tape) is used to temporarily fix semiconductor substrates.

[0003] For example, Patent Document 1 discloses a semiconductor processing sheet (adhesive tape) that includes a substrate and an adhesive layer laminated on the substrate. This semiconductor processing sheet is used so that the adhesive layer adheres tightly to semiconductor wafers, semiconductor packages, etc. This allows the semiconductor wafers, semiconductor packages, etc. to be temporarily fixed.

[0004] However, the semiconductor processing sheet (conventional adhesive tape) described in Patent Document 1 has the following problems.

[0005] During the manufacturing process of semiconductor devices, the outer periphery of the adhesive layer of a semiconductor processing sheet is fixed with a ring frame, and then the backside of a semiconductor substrate is attached to the adhesive layer. If the semiconductor substrate is warped, the warp may be straightened before the semiconductor substrate is attached to the semiconductor processing sheet. The semiconductor substrate attached to the semiconductor processing sheet may then be immediately transferred to the next process, or it may be released from straightening and left for a while. However, when released from straightening, the semiconductor substrate attempts to return to its warped state, generating a peel force that causes the backside of the semiconductor substrate to separate from the adhesive layer. This peel force can cause delamination between the semiconductor substrate and the semiconductor processing sheet, which presents a problem. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2023-108418 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide an adhesive tape that can prevent peeling between a substrate and an adhesive layer due to warping of the substrate. [Means for solving the problem]

[0008] These objects can be achieved by the present invention as set forth in (1) to (8) below. (1) An adhesive tape comprising a base material and an adhesive layer laminated on one surface of the base material, the adhesive tape being used to temporarily fix a substrate, A pressure-sensitive adhesive tape characterized in that when a test piece measuring 25 mm in width and 200 mm in length is attached to the mirror surface of a silicon wafer and then subjected to a 90-degree slow peel test in accordance with the test method specified in JIS Z 0237:2009, in which the test piece is peeled in a 90-degree direction at a peel rate of 10 mm / min, the measured value is 1000 mN / 25 mm or more.

[0009] (2) The adhesive tape according to (1) above, wherein the adhesive layer contains a tackifier.

[0010] (3) The adhesive layer contains a base resin, The adhesive tape according to (2) above, wherein the blending ratio of the tackifier to 100 parts by mass of the base resin is 10 parts by mass or more and 100 parts by mass or less.

[0011] (4) The adhesive layer contains an acrylic resin as a base resin, The pressure-sensitive adhesive tape according to (1) above, wherein the acrylic resin contains a structure derived from an amide monomer.

[0012] (5) The pressure-sensitive adhesive tape according to (4), wherein the acrylic resin has a main chain and a side chain containing an amide bond derived from the amide monomer.

[0013] (6) The adhesive tape according to (4) or (5) above, wherein the content of the amide monomer is 1 part by mass or more and 30 parts by mass or less when the total amount of all monomer components constituting the acrylic resin is 100 parts by mass.

[0014] (7) The adhesive tape according to any one of claims (1) to (6), wherein the adhesive layer contains a curable resin that is cured by irradiation with energy rays.

[0015] (8) The pressure-sensitive adhesive tape according to (1) above, wherein the test piece, which is set to a width of 25 mm and a length of 200 mm, is attached to the mirror surface of a silicon wafer, and then subjected to a 180-degree high-speed peel test in which the test piece is peeled in a 180-degree direction at a peel rate of 300 mm / min in a manner conforming to the test method specified in JIS Z 0237:2009, so that the measured value is 2500 [mN / 25 mm] or more. [Effects of the Invention]

[0016] According to the present invention, an adhesive tape can be obtained that can suppress peeling between the substrate and the adhesive layer due to warping of the substrate. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a vertical cross-sectional view showing an example of a semiconductor device manufactured using an adhesive tape according to the present invention. [Figure 2] 1A to 1C are longitudinal cross-sectional views illustrating a method for manufacturing a semiconductor device using the adhesive tape according to the embodiment. [Figure 3] 1A to 1C are longitudinal cross-sectional views illustrating a method for manufacturing a semiconductor device using the adhesive tape according to the embodiment. [Figure 4] 1 is a longitudinal cross-sectional view showing a pressure-sensitive adhesive tape according to an embodiment. [Figure 5] FIG. 1 is a perspective view showing a test piece used in a 90-degree low-speed peel test. [Figure 6] FIG. 6 is a schematic diagram showing a state in which a 90-degree low-speed peel test is performed on the test piece shown in FIG. 5. [Figure 7]FIG. 6 is a schematic diagram showing a state in which a 180-degree high-speed peel test is performed on the test piece shown in FIG. 5. DETAILED DESCRIPTION OF THE INVENTION

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The pressure-sensitive adhesive tape according to the present invention will be described in detail below with reference to preferred embodiments shown in the accompanying drawings.

[0019] 1. Semiconductor Devices First, prior to describing the adhesive tape according to the present invention, an example of a semiconductor device manufactured using the adhesive tape will be described.

[0020] Fig. 1 is a longitudinal sectional view showing an example of a semiconductor device manufactured using the adhesive tape according to the present invention. In the following description, the upper side in Fig. 1 will be referred to as "top" and the lower side as "bottom." In addition, in each drawing of the present application, the dimensional ratios in the left-right direction and the thickness direction may differ from the actual ratios.

[0021] The semiconductor device 10 shown in Figure 1 has a semiconductor chip 20 (semiconductor element), an interposer 30 (substrate) that supports the semiconductor chip 20, a plurality of conductive bumps 70 (terminals), and a molded portion 17 (sealing portion) that seals the semiconductor chip 20.

[0022] The interposer 30 is an insulating substrate and is made of various resin materials such as polyimide, epoxy resin, cyanate resin, bismaleimide triazine resin (BT resin), etc. The planar shape of the interposer 30 can be, for example, a quadrilateral such as a square or a rectangle.

[0023] On the upper surface of the interposer 30, terminals 41 made of a conductive metal material such as copper are provided in a predetermined shape.

[0024] Furthermore, a plurality of vias (through holes) and through wiring (not shown) are formed in the interposer 30 so as to penetrate the interposer 30 in the thickness direction.

[0025] Each bump 70 protrudes from the lower surface of the interposer 30. Each bump 70 is electrically connected to a terminal 41 via a through-wiring. Such a bump 70 is mainly made of a brazing material such as solder, silver brazing, copper brazing, or phosphorus copper brazing.

[0026] Terminals 41 provided on the interposer 30 are electrically connected to terminals 21 of the semiconductor chip 20 via connecting portions 81 .

[0027] An underfill material is filled in the gap between the semiconductor chip 20 and the interposer 30. The hardened underfill material forms a sealing layer 80. This sealing layer 80 improves the bonding strength between the semiconductor chip 20 and the interposer 30 and prevents the intrusion of foreign matter, moisture, and the like into the gap.

[0028] A molded portion 17 is provided on the upper side of the interposer 30 so as to cover the semiconductor chip 20 and the interposer 30. The molded portion 17 is made of a hardened semiconductor sealing material (sealant). By providing the molded portion 17, the semiconductor chip 20 is sealed, and the intrusion of foreign matter, moisture, etc. into the semiconductor chip 20 is prevented.

[0029] 1, the semiconductor chip 20 (semiconductor element) has a semiconductor chip body 23 (semiconductor element body) and terminals 21 provided on the lower surface of the semiconductor chip body 23. A circuit (not shown) is formed on the upper surface of the semiconductor chip body 23. Examples of materials that can be used to form the semiconductor chip body 23 include semiconductor materials such as Si, SiC, GaN, and Ga2O3.

[0030] 2. Manufacturing method of semiconductor device Next, an example of a method for manufacturing the semiconductor device 10 using the adhesive tape according to the embodiment will be described.

[0031] 2 and 3 are vertical cross-sectional views for explaining a method for manufacturing a semiconductor device 10 using the pressure-sensitive adhesive tape 100 according to the embodiment. In the following explanation, the upper side in each figure will be referred to as "upper" and the lower side will be referred to as "lower."

[0032] [1A] First, a semiconductor substrate 7 (semiconductor wafer) and an adhesive tape 100 are prepared. The adhesive tape 100 shown in FIG. 2(a) has a base material 4 and an adhesive layer 2 laminated on the base material 4. Next, as shown in FIG. 2(a), an outer periphery 121 of the adhesive layer 2 of the adhesive tape 100 is fixed with a wafer ring 9. Then, the underside of the semiconductor substrate 7 (semiconductor wafer) is attached to a central portion 122 of the adhesive layer 2.

[0033] However, as shown in FIG. 2(b), warpage may occur in the semiconductor substrate 7. In the process of attaching the semiconductor substrate 7 to the adhesive tape 100, the semiconductor substrate 7 may be attached to the adhesive tape 100 while being sucked onto a chuck table (not shown) or the like. In such a case, the warpage of the semiconductor substrate 7 is maintained in a straightened state. Thereafter, when the semiconductor substrate 7 is released from the straightening, the semiconductor substrate 7 attempts to return to its warped state. In this case, the adhesive tape 100 conforms to the underside of the semiconductor substrate 7, as shown in FIG. 2(b). As a result, tensile stress and shear stress are generated in the adhesive tape 100, which may result in peeling starting from the edge of the semiconductor substrate 7.

[0034] Therefore, the adhesive tape 100 (adhesive tape according to the embodiment) is required to suppress peeling due to warping of the semiconductor substrate 7. The adhesive tape 100 will be described in detail later.

[0035] [2A] Next, as shown in FIG. 2(c), the adhesive tape 100 to which the semiconductor substrate 7 is attached is placed on a dicer table 200.

[0036] [3A] Next, a dicing saw (blade) (not shown) is used to cut the semiconductor substrate 7 into individual pieces (dicing process). As a result, a plurality of semiconductor chips 20 are obtained on the adhesive tape 100, as shown in FIG. 2(d). At this time, the adhesive tape 100 has a cushioning effect, so that cracks, chips, etc. in the semiconductor substrate 7 can be prevented. Furthermore, it is preferable that the cut marks made by the dicing saw reach the base material 4, as shown in FIG. 2(d). This allows the semiconductor substrate 7 to be reliably cut into individual pieces.

[0037] If necessary, cutting may be performed while supplying water to the semiconductor substrate 7. This makes it possible to prevent scattering of dust and overheating of the semiconductor substrate 7 that occurs when cutting the semiconductor substrate 7.

[0038] [4A] Next, as shown in FIG. 2(e), the adhesive tape 100 is irradiated with energy rays E such as ultraviolet rays (energy ray irradiation process). In the adhesive tape 100 irradiated with the energy rays E, the adhesive strength of the adhesive layer 2 is reduced. This allows the semiconductor chip 20 to be easily picked up in the pick-up process described later.

[0039] [5A] Next, the adhesive tape 100 with the semiconductor substrate 7 attached thereto is placed on an expanding table 300. The expanding table 300 includes an expanding stage 310 corresponding to the center of the semiconductor substrate 7 and a holder 320 corresponding to the outer periphery of the semiconductor substrate 7. In the pick-up process, as shown in FIG. 3(a), the expanding stage 310 is pushed upward against the holder 320 of the expanding table 300. This causes the adhesive tape 100 to be stretched radially, and gaps are formed between the semiconductor chips 20 obtained by singulation (expanding process).

[0040] [6A] Next, the adhesive tape 100 to which the expanding semiconductor substrate 7 has been attached is placed on a pickup table 400. Then, the semiconductor chip 20 is picked up by a suction tool (not shown) such as a vacuum collet or air tweezers, as shown in FIG. 3(b) (pickup process). In the pick-up process, the semiconductor chip 20 may be pushed up from below by a needle (not shown).

[0041] By going through the above-described steps [1A] to [6A], the individual semiconductor chips 20 are obtained. The individual semiconductor chips 20 are placed on, for example, the interposer 30 shown in FIG. 1. Then, the sealing layer 80 and the molded portion 17 are provided. In this way, the semiconductor device 10 shown in FIG. 1 is obtained.

[0042] 3. Adhesive tape Fig. 4 is a vertical cross-sectional view showing the pressure-sensitive adhesive tape 100 according to the embodiment. In the following description, the upper side in Fig. 4 will be referred to as "top" and the lower side as "bottom".

[0043] The adhesive tape 100 is an adhesive tape used to temporarily fix a semiconductor substrate 7, and as shown in Fig. 4, comprises a base material 4 and an adhesive layer 2. The adhesive layer 2 is laminated on the upper surface (one surface) of the base material 4. The adhesive tape 100 is configured so as to satisfy predetermined measured values ​​when subjected to a 90-degree slow peel test.

[0044] With this configuration, the adhesive tape 100 exhibits good conformability even when the semiconductor substrate 7 is warped. Therefore, even when the warped semiconductor substrate 7 is attached to the adhesive tape 100 in a straightened state and then released from the straightening, the adhesive tape 100 is likely to maintain a state of close contact with the semiconductor substrate 7. Therefore, it is possible to realize the adhesive tape 100 that can suppress peeling between the semiconductor substrate 7 and the adhesive layer 2 due to warping of the semiconductor substrate 7.

[0045] 3.1.90 degree slow peel test As described above, the adhesive tape 100 is configured to satisfy predetermined measurement values ​​when subjected to a 90-degree slow peel test.

[0046] Fig. 5 is a perspective view showing a test piece 110 used in a 90-degree slow peel test. The test piece 110 shown in Fig. 5 is a tape piece cut out from the pressure-sensitive adhesive tape 100, and includes a test substrate 114 and a test adhesive layer 112 laminated on one side of the test substrate 114. The test piece 110 is set to have a width of 25 mm and a length of 200 mm.

[0047] FIG. 6 is a schematic diagram showing a 90-degree slow peel test performed on the test piece 110 shown in FIG. 5. The 90-degree slow peel test conforms to "Method 6" of the adhesive tape test specified in JIS Z 0237:2009. As shown in FIG. 6, the test piece 110 is attached to a test plate 116, left to stand for at least three hours, and then the test piece 110 is peeled at a 90-degree angle relative to the test plate 116 at a peel speed of 10 mm / min to measure the adhesive strength. The test environment is a temperature of 23±1°C and a relative humidity of 50±5%. A silicon wafer is used as the test plate 116. The surface 117 of the test plate 116 to which the test piece 110 is attached is a mirror-finished silicon wafer as specified in JIS H 0614:1996.

[0048] The pressure-sensitive adhesive tape 100 is configured so that the measured value in the 90-degree slow peel test described above is 1000 [mN / 25 mm] or more. The 90-degree slow peel test uses a 90-degree peel direction and a slow peel speed, allowing for quantitative evaluation of the effect of a warped semiconductor substrate 7 on the pressure-sensitive adhesive tape 100. Therefore, when the measured value in the 90-degree slow peel test is within the above-mentioned range, the pressure-sensitive adhesive tape 100 can be evaluated as having adhesiveness that can adequately withstand a low-speed peel force. Therefore, by configuring the substrate 4 and the adhesive layer 2 so that the measured value in the 90-degree slow peel test is within the above-mentioned range, a pressure-sensitive adhesive tape 100 can be realized that can inhibit peeling between the semiconductor substrate 7 and the adhesive layer 2, even when the semiconductor substrate 7 is warped.

[0049] The measured value in the 90-degree low-speed peel test is preferably 1250 [mN / 25 mm] or more, and more preferably 1500 [mN / 25 mm] or more.

[0050] The measured value in the 90-degree low-speed peel test is preferably 10,000 [mN / 25 mm] or less, and more preferably 7,500 [mN / 25 mm] or less, which can prevent wafer contamination after peeling due to poor curing or the like.

[0051] If the measured value is below the lower limit, peeling is likely to occur at the interface between the semiconductor substrate 7 and the adhesive tape 100 when a warped semiconductor substrate 7 is attached. On the other hand, if the measured value is above the upper limit, the adhesive strength of the adhesive layer 2 becomes excessive. In this case, the adhesive strength of the adhesive layer 2 may not be sufficiently reduced after the energy ray irradiation treatment, which may result in pickup failure or the like.

[0052] 3.2.180° high-speed peel test The pressure-sensitive adhesive tape 100 is preferably configured so as to satisfy predetermined measurement values ​​when a test piece 110 shown in FIG. 5 is subjected to a 180-degree high-speed peel test.

[0053] FIG. 7 is a schematic diagram showing a 180-degree high-speed peel test being performed on the test piece 110 shown in FIG. 5. The 180-degree high-speed peel test conforms to "Method 1" of the adhesive tape tests specified in JIS Z 0237:2009. After attaching the test piece 110 to the test plate 116, the test piece 110 is peeled off in a 180-degree direction relative to the test plate 116 within one minute, and the adhesive strength is measured at a peel speed of 300 mm / min. The test environment is a temperature of 23±1°C and a relative humidity of 50±5%. A silicon wafer is used as the test plate 116. The surface 117 of the test plate 116 to which the test piece 110 is attached is a mirror-finished silicon wafer as specified in JIS H 0614:1996.

[0054] The pressure-sensitive adhesive tape 100 is preferably configured so that the measured value in the 180-degree high-speed peel test described above is 2500 [mN / 25 mm] or more. In the 180-degree high-speed peel test, the peeling direction is 180 degrees and the peeling speed is high, so that the stability of fixation of the semiconductor substrate 7 during, for example, a dicing process that generates vibrations can be quantitatively evaluated. Therefore, when the measured value in the 180-degree high-speed peel test is within the above range, a pressure-sensitive adhesive tape 100 that can well hold a chip during dicing can be realized.

[0055] The measured value in the 180-degree high-speed peel test is preferably 3500 [mN / 25 mm] or more, and more preferably 4000 [mN / 25 mm] or more.

[0056] The measured value in the 180-degree high-speed peel test is preferably 15,000 [mN / 25 mm] or less, and more preferably 12,500 [mN / 25 mm] or less, which can suppress wafer contamination after peeling due to poor curing, etc.

[0057] If the measured value is below the lower limit, when a warped semiconductor substrate 7 is attached, the semiconductor substrate 7 may not be stably fixed during dicing, pick-up, or the like. On the other hand, if the measured value is above the upper limit, the adhesive strength of the adhesive layer 2 may become excessive. In this case, the adhesive strength of the adhesive layer 2 may not be sufficiently reduced after the energy ray irradiation process.

[0058] 3.3.Layer configuration The adhesive tape 100 includes a substrate 4 and an adhesive layer 2. Each part of the adhesive tape 100 will be described in detail below.

[0059] 3.3.1. Base material Resin materials, for example, can be used as a constituent material of the substrate 4. Examples of resin materials used for the substrate 4 include thermoplastic resins such as olefin resins, polyester resins (ester polymers) such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, and polybutylene naphthalate, polyvinyl chloride resins, polyurethanes, polyimides, polyamides, polyether ketones such as polyether ether ketone, polyethersulfone, polystyrene, fluororesins, silicone resins, cellulose resins, styrene thermoplastic elastomers (styrene polymers), acrylic resins, polyester thermoplastic elastomers, polyvinyl isoprene, and polycarbonates (carbonate polymers), as well as mixtures containing these thermoplastic resins.

[0060] These resin materials are materials that can transmit energy rays such as visible light, near-infrared rays, ultraviolet rays, X-rays, and electron beams, and therefore, in the energy ray irradiation treatment described above, the irradiated energy rays E penetrate the base material 4 and are irradiated onto the adhesive layer 2. Therefore, the adhesive strength of the adhesive layer 2 can be more reliably reduced.

[0061] The substrate 4 may contain softeners such as mineral oil, fillers such as calcium carbonate, silica, talc, mica, and clay, antioxidants, light stabilizers, lubricants, dispersants, neutralizers, colorants, and the like.

[0062] The content of the resin material in the base material 4 is preferably 50% by mass or more, and more preferably 80% by mass or more, which ensures good flexibility of the base material 4 and good adhesion of the base material 4 to the adhesive layer 2.

[0063] The thickness of the substrate 4 is not particularly limited, but is preferably 30 μm or more and 200 μm or less, and more preferably 40 μm or more and 150 μm or less. When the thickness of the substrate 4 is within this range, the mechanical properties of the substrate 4 are optimized, and the substrate 4 can more reliably perform its functions. This makes it possible to prevent breakage of the substrate 4 during dicing, expanding, picking up, and other processes.

[0064] The surface roughness Ra of the substrate 4 is, for example, preferably 0.2 μm or more and 2.0 μm or less, and more preferably 0.5 μm or more and 1.5 μm or less. When the surface roughness Ra of the substrate 4 is within this range, the adhesion between the substrate 4 and the adhesive layer 2 is improved. This makes it possible to prevent peeling between the substrate 4 and the adhesive layer 2 during the pick-up process.

[0065] 3.3.2. Adhesive layer The adhesive layer 2 has enough adhesiveness to support the semiconductor substrate 7 during the dicing process and to allow the semiconductor chip 20 to be picked up well during the pick-up process.

[0066] The adhesive layer 2 contains a base resin, a crosslinking agent, a photopolymerization initiator, etc. Furthermore, if necessary, it also contains a curable resin that hardens when irradiated with energy rays, a tackifier that enhances adhesion, etc. Each component will be described below.

[0067] 3.3.2.1. Base Resin (A) The base resin (A) contains an adhesive and provides the adhesive layer 2 with adhesiveness to the semiconductor substrate 7 .

[0068] Examples of the base resin (A) include various resins used as adhesives, such as acrylic resins, silicone resins, polyester resins, polyvinyl acetate resins, polyvinyl ether resins, styrene elastomer resins, polyisoprene resins, polyisobutylene resins, and urethane resins. One or more of these resins are used as the base resin (A). Of these, acrylic resins are preferably used as the base resin (A). Acrylic resins have excellent heat resistance.

[0069] In this specification, the acrylic resin refers to a polymer (homopolymer or copolymer) containing a (meth)acrylic acid ester as a monomer component. In addition, in this specification, (meth)acrylic acid includes both acrylic acid and methacrylic acid. Therefore, for example, (meth)acrylic acid ester includes both acrylic acid ester and methacrylic acid ester.

[0070] Examples of the (meth)acrylic acid ester include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, Examples thereof include (meth)acrylic acid alkyl esters such as 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; (meth)acrylic acid cycloalkyl esters such as cyclohexyl (meth)acrylate; and (meth)acrylic acid aryl esters such as phenyl (meth)acrylate, and these may be used alone or in combination of two or more.

[0071] Among these, (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and octyl (meth)acrylate are preferably used. (Meth)acrylic acid alkyl esters have excellent heat resistance and are relatively easy and inexpensive to obtain.

[0072] The acrylic resin may contain a structure derived from a copolymerizable monomer for the purpose of improving properties such as cohesive strength and heat resistance.

[0073] Such copolymerizable monomers are not particularly limited, but examples thereof include hydroxyl group-containing monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate; epoxy group-containing monomers such as glycidyl (meth)acrylate; carboxyl group-containing monomers such as (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid; and acids such as maleic anhydride and itaconic anhydride. anhydride group-containing monomers, amide monomers such as (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-butyl(meth)acrylamide, N-methylol(meth)acrylamide, N-methylolpropane(meth)acrylamide, N-methoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, and N-hexyl(meth)acrylamide, aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, and t-butylaminoethyl (meth)acrylate, Examples of suitable monomers include cyano group-containing monomers, cyano group-containing monomers such as (meth)acrylonitrile, olefin-based monomers such as ethylene, propylene, isoprene, butadiene, and isobutylene, styrene-based monomers such as styrene, α-methylstyrene, and vinyltoluene, vinyl ester-based monomers such as vinyl acetate and vinyl propionate, vinyl ether-based monomers such as methyl vinyl ether and ethyl vinyl ether, halogen atom-containing monomers such as vinyl chloride and vinylidene chloride, alkoxy group-containing monomers such as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate, and monomers having a nitrogen atom-containing ring, such as N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-vinylmorpholine, N-vinylcaprolactam, and N-(meth)acryloylmorpholine. These may be used alone or in combination of two or more.

[0074] The content of the copolymerizable monomer is preferably 1% by mass to 70% by mass, more preferably 2% by mass to 60% by mass, and even more preferably 5% by mass to 50% by mass, of all the monomer components constituting the acrylic resin, which allows the properties derived from the copolymerizable monomer to be appropriately imparted, thereby favorably modifying the properties of the acrylic resin.

[0075] Furthermore, the copolymerizable monomer is preferably an amide monomer. That is, the acrylic resin preferably contains a structure derived from an amide monomer. The structure derived from an amide monomer introduces an amide bond into the side chain of the base resin (A). This amide bond is thought to provide unique adhesive properties based on intermolecular interactions. Therefore, by containing a base resin (A) containing a structure derived from an amide monomer, i.e., an amide bond-introduced acrylic resin (A2), the adhesive layer 2 has adhesive properties that can adequately withstand low-speed peel forces. This ensures that the adhesive tape 100 has a measurement value in the 90-degree low-speed peel test within the aforementioned range. Furthermore, the amide bond in the side chain improves the chemical resistance of the adhesive layer 2.

[0076] The content of the amide monomer is preferably 1 part by mass or more and 30 parts by mass or less, more preferably 2 parts by mass or more and 20 parts by mass or less, and even more preferably 3 parts by mass or more and 8 parts by mass or less, when the total amount of all monomer components constituting the acrylic resin is 100 parts by mass.

[0077] By setting the content of the amide-based monomer within the above range, the above-mentioned properties derived from the amide-based monomer are accurately imparted to the adhesive layer 2. This increases the probability that the measured values ​​in the 90-degree low-speed peel test will fall within the above range. Furthermore, the measured values ​​in the 180-degree high-speed peel test will also fall within the above range. As a result, an adhesive tape 100 is obtained that can suppress peeling and dicing defects even when a warped semiconductor substrate 7 is attached.

[0078] Furthermore, it has properties that can withstand both low-speed peeling and high-speed peeling, and can also suppress the occurrence of pickup defects. Pickup defects include defects caused by components contained in the adhesive layer 2 adhering to the picked-up semiconductor chip 20. In contrast, since the amide bond is introduced as a side chain in the amide bond-introduced acrylic resin (A2), it is difficult to detach and is unlikely to cause pickup defects.

[0079] If the content of the amide-based monomer is below the lower limit, the measured value in the 90-degree low-speed peel test may be below the range. Also, the measured value in the 180-degree high-speed peel test may be outside the range. On the other hand, if the content of the amide-based monomer is above the upper limit, the measured value in the 90-degree low-speed peel test may be above the range. Also, the measured value in the 180-degree high-speed peel test may be outside the range.

[0080] The copolymerizable monomer may be contained at the end of the polymer main chain, in the middle of the polymer main chain, or both at the end and in the middle of the polymer main chain. The copolymerizable monomer may contain a polyfunctional monomer for the purpose of crosslinking between polymer main chains, etc.

[0081] Examples of polyfunctional monomers include 1,6-hexanediol (meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, glycerin di(meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, urethane (meth)acrylate, divinylbenzene, butyl di(meth)acrylate, and hexyl di(meth)acrylate, and these can be used alone or in combination of two or more.

[0082] Furthermore, ethylene-vinyl acetate copolymers and vinyl acetate polymers can also be used as components having the same function as the copolymerizable monomer.

[0083] Acrylic resins can be produced by polymerizing a single monomer component or a mixture of two or more monomer components, and the polymerization of these monomer components can be carried out using polymerization methods such as solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization.

[0084] The acrylic resin may have a functional group (reactive functional group) that is reactive with a crosslinking agent or a photopolymerization initiator, such as a hydroxyl group or a carboxyl group. This allows the crosslinking agent or the photopolymerization initiator to be linked to the acrylic resin, thereby preventing the crosslinking agent or the photopolymerization initiator from leaking from the adhesive layer 2. As a result, the adhesive strength of the adhesive layer 2 after the energy ray irradiation treatment can be more reliably reduced.

[0085] 3.3.2.2. Physical properties of base resin (A) From the viewpoint of preventing contamination of the semiconductor substrate 7 and the like during the dicing process, it is preferable that the base resin (A) has a low content of low-molecular-weight substances. From this viewpoint, the weight-average molecular weight of the base resin (A) is preferably 300,000 to 2,000,000, more preferably 400,000 to 1,800,000, and even more preferably 500,000 to 1,500,000. If the weight-average molecular weight of the base resin (A) is below the lower limit, depending on the type of monomer component, the contamination prevention properties against the semiconductor substrate 7 and the like may be reduced, resulting in the risk of components contained in the adhesive layer 2 adhering to the semiconductor chip 20. On the other hand, if the weight-average molecular weight of the base resin (A) is above the upper limit, the viscosity of the composition for forming the adhesive layer 2 may be increased, which may increase the difficulty of manufacturing the adhesive tape 100. The weight-average molecular weight is calculated as a standard polystyrene equivalent by gel permeation chromatography (GPC).

[0086] The glass transition temperature Tg of the base resin (A) is preferably -80°C or higher and -10°C or lower, more preferably -70°C or higher and -15°C or lower, and even more preferably -60°C or higher and -20°C or lower. This allows the adhesive strength of the adhesive layer 2 to be optimized. If the glass transition temperature Tg is below the lower limit, the base resin (A) will not easily aggregate, which may cause components contained in the adhesive layer 2 to adhere to the picked-up semiconductor chip 20. On the other hand, if the glass transition temperature Tg is above the upper limit, the adhesive strength of the adhesive layer 2 will be insufficient, which may result in defects during the dicing process.

[0087] The glass transition temperature Tg is appropriately adjusted depending on the monomer components constituting the base resin (A), the molecular weight, etc. The glass transition temperature Tg is measured using a differential scanning calorimeter (DSC) at a temperature rise rate of 0.1°C / min.

[0088] The content of the base resin (A) in the resin composition constituting the adhesive layer 2 is preferably 30% by mass or more and 90% by mass or less, and more preferably 40% by mass or more and 80% by mass or less, of the total solid content of the resin composition.

[0089] 3.3.2.3.Curing resin (B) The curable resin (B) is added as needed and is a resin having a curing property that allows it to be cured by irradiation with energy rays. Such a curable resin (B) imparts curing properties to the adhesive layer 2 in association with the energy ray irradiation treatment. This makes it possible to effectively reduce the adhesive strength of the adhesive layer 2 after the energy ray irradiation treatment.

[0090] The curable resin (B) may, for example, be a low molecular weight compound having in its molecule at least two groups containing polymerizable carbon-carbon double bonds that are three-dimensionally crosslinked by irradiation with energy rays.

[0091] Specific examples of the group containing a polymerizable carbon-carbon double bond include a (meth)acryloyl group, a (meth)acryloyloxy group, a (meth)acryloylamino group, an allyl group, a 1-propenyl group, and a vinyl group.

[0092] Examples of the low molecular weight compound include esters of (meth)acrylic acid and polyhydric alcohols such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, and glycerin di(meth)acrylate; ester acrylate oligomers; cyanurate compounds having a carbon-carbon double bond-containing group such as 2-propenyl-di-3-butenyl cyanurate; tris(2-acryloxyethyl)isocyanurate; tris(2-acryloxyethyl)isocyanurate; Examples of the acrylate include isocyanurate compounds having a carbon-carbon double bond-containing group, such as (2-methacryloxyethyl)isocyanurate, 2-hydroxyethylbis(2-acryloxyethyl)isocyanurate, bis(2-acryloxyethyl)2-[(5-acryloxyhexyl)-oxy]ethylisocyanurate, tris(1,3-diacryloxy-2-propyl-oxycarbonylamino-n-hexyl)isocyanurate, tris(1-acryloxyethyl-3-methacryloxy-2-propyl-oxycarbonylamino-n-hexyl)isocyanurate, and tris(4-acryloxy-n-butyl)isocyanurate; commercially available oligoester acrylates; aromatic and aliphatic urethane acrylates; and epoxy acrylates such as bisphenol A epoxy acrylate, phenol novolac epoxy acrylate, and cresol novolac epoxy acrylate. These may be used alone or in combination of two or more.

[0093] Among these, it is preferable to include at least one of an ester of (meth)acrylic acid and a polyhydric alcohol, a urethane acrylate, and an epoxy acrylate, and it is more preferable to include a bisphenol A-type epoxy acrylate, which allows the curable resin (B) to be cured more reliably by irradiation with energy rays.

[0094] The number of functional groups (the number of groups containing a polymerizable carbon-carbon double bond) per molecule of the curable resin (B) may be 2 or more, preferably 3 or more, and more preferably 4 to 6. This can increase the reactivity of the curable resin (B), and can more reliably achieve good releasability in the adhesive layer 2 after energy ray irradiation and suppression of defects during the pick-up process.

[0095] The weight-average molecular weight of the curable resin (B) is preferably smaller than that of the base resin (A). It is more preferably 100 or more and 1000 or less, and even more preferably 200 or more and 500 or less. This allows for an adhesive layer 2 with better adhesion and curability. The weight-average molecular weight is measured by gel permeation chromatography (GPC) in terms of standard polystyrene.

[0096] The blending ratio of the curable resin (B) is preferably 0 to 180 parts by mass, more preferably 3 to 160 parts by mass, even more preferably 5 to 140 parts by mass, and particularly preferably 8 to 120 parts by mass, per 100 parts by mass of the base resin (A). This allows the function of the curable resin (B) to be more effectively exhibited. Note that when the base resin (A) contains a double bond-introduced acrylic resin (A1), the base resin (A) alone is curable. In this case, the curable resin (B) may be omitted.

[0097] 3.3.2.4. Tackifier The adhesive layer 2 may contain a tackifier together with the base resin (A). The tackifier forms aggregates and is present between the polymers that make up the base resin (A), thereby further increasing the elastic modulus of the adhesive layer 2. Therefore, the tackifier imparts to the adhesive layer 2 adhesion that can adequately withstand a low-speed peel force. This ensures that the adhesive tape 100 has a measurement value in a 90-degree low-speed peel test that falls within the aforementioned range.

[0098] Examples of tackifiers contained in the adhesive layer 2 include rosin-based tackifiers, terpene-based tackifiers, and petroleum resin-based tackifiers, and one or more of these can be used in combination. Of these, the tackifier contained in the adhesive layer 2 is preferably a rosin-based tackifier. Use of a rosin-based tackifier can impart to the adhesive layer 2 not only adhesion that can adequately withstand low-speed peel forces, but also adhesion that can adequately withstand high-speed peel forces. This can reliably achieve an adhesive tape 100 whose measured values ​​in a 90-degree low-speed peel test and a 180-degree high-speed peel test are each within the aforementioned ranges.

[0099] Examples of rosin-based tackifiers include esters of rosin acid, the main component of which is abietic acid in rosin resin or pine oil, with glycerin or pentaerythritol, and hydrogenated products thereof. Specific examples include gum rosin, tall oil rosin, wood rosin, hydrogenated rosin, polymerized rosin, modified rosin, and rosin ester. Among these, polymerized rosin ester-based tackifiers are preferably used.

[0100] The polymerized rosin ester tackifier preferably contains a rosin dimer structure (rosin dimer). The rosin dimer is preferably a compound represented by the following formula (1) or (2), more preferably a compound represented by the following formula (2):

[0101] [ka]

[0102] [ka]

[0103] The rosin dimer preferably has two or more functional groups (ROOC-), as in the above formulas (1) and (2), which reliably realizes a pressure-sensitive adhesive tape 100 whose measured values ​​in the 90-degree slow peel test and the 180-degree high-speed peel test are within the above-mentioned ranges.

[0104] The functional group (ROOC-) is a carboxy group or a carboxylic acid ester group. When the tackifier has multiple functional groups (ROOC-), the functional groups (ROOC-) may be the same as or different from each other.

[0105] In the case of a carboxylic acid ester group, R is an alkyl group having 1 to 5 carbon atoms or a benzyl group.

[0106] The polymerized rosin ester tackifier containing such a structure imparts to the adhesive layer 2 adhesiveness that can particularly effectively resist a low-speed peeling force.

[0107] Terpene tackifiers include those obtained by polymerizing natural terpenes such as terpene oil contained in pine trees and natural terpenes contained in orange peel, etc. Specific examples include terpene resins, aromatic modified terpene resins, and hydrogenated terpene resins.

[0108] Examples of petroleum resin-based tackifiers include aliphatic, alicyclic, and aromatic resins made from petroleum, such as C5 petroleum resins, C9 petroleum resins, copolymer petroleum resins, alicyclic saturated hydrocarbon resins, and styrene petroleum resins.

[0109] The blending ratio of the tackifier is preferably 0.5 parts by mass or more and 30 parts by mass or less, more preferably 1.5 parts by mass or more and 20 parts by mass or less, and even more preferably 4 parts by mass or more and 16 parts by mass or less, relative to 100 parts by mass of the base resin (A). By setting the blending ratio of the tackifier within the above range, it is possible to more reliably realize a pressure-sensitive adhesive tape 100 in which the measured values ​​in the 90-degree low-speed peel test and the measured values ​​in the 180-degree high-speed peel test are each within the above range.

[0110] 3.3.2.5. Photoinitiators The adhesive layer 2 preferably contains a photopolymerization initiator, which facilitates the initiation of polymerization of the double bond-introduced acrylic resin (A1) and the curable resin (B).

[0111] Examples of the photopolymerization initiator include 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl) ketone, α-hydroxy-α,α'- Dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, 1-hydroxycyclohexyl phenyl ketone, Michler's ketone, acetophenone, methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinopropane-1, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl, benzoin, Dibenzyl, α-hydroxycyclohexyl phenyl ketone, benzil dimethyl ketal, 2-hydroxymethylphenylpropane, 2-naphthalenesulfonyl chloride, 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime, benzophenone, benzoylbenzoic acid, 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-4-methoxybenzophenone, o-acryloxybenzophenone, p-acryloxybenzophenone Benzophenone-4-carboxylic acid esters of acrylates such as benzophenone, o-methacryloxybenzophenone, p-methacryloxybenzophenone, p-(meth)acryloxyethoxybenzophenone, 1,4-butanediol mono(meth)acrylate, 1,2-ethanediol mono(meth)acrylate, 1,8-octanediol mono(meth)acrylate, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,Examples include 4-diethylthioxanthone, 2,4-diisopropylthioxanthone, azobisisobutyronitrile, β-chloroanthraquinone, camphorquinone, halogenated ketones, acylphosphinoxides, acylphosphonates, polyvinylbenzophenone, chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, 2-ethylanthraquinone, t-butylanthraquinone, and 2,4,5-triarylimidazole dimers, and these can be used alone or in combination of two or more.

[0112] The photopolymerization initiator is preferably blended in an amount of 0.1 to 50 parts by mass, and more preferably 0.5 to 10 parts by mass, per 100 parts by mass of the base resin (A). By adjusting the blending amount of the photopolymerization initiator as described above, the function exhibited by adding the photopolymerization initiator can be reliably exhibited, and excess photopolymerization initiator can be avoided.

[0113] Crosslinking Agents The resin composition constituting the adhesive layer 2 may contain a crosslinking agent. By containing a crosslinking agent, the adhesive layer 2 can be adjusted to have an appropriate hardness.

[0114] The crosslinking agent is not particularly limited, but examples thereof include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, urea resin-based crosslinking agents, methylol-based crosslinking agents, chelate-based crosslinking agents, aziridine-based crosslinking agents, melamine-based crosslinking agents, polyvalent metal chelate-based crosslinking agents, acid anhydride-based crosslinking agents, polyamine-based crosslinking agents, carboxyl group-containing polymer-based crosslinking agents, etc. Among these, isocyanate-based crosslinking agents are preferred.

[0115] The isocyanate-based crosslinking agent is not particularly limited, but examples thereof include polyisocyanate compounds of polyvalent isocyanates, trimers of polyisocyanate compounds, trimers of isocyanate-terminated compounds obtained by reacting a polyisocyanate compound with a polyol compound, and blocked polyisocyanate compounds in which isocyanate-terminated urethane prepolymers are blocked with phenol, oximes, or the like.

[0116] Examples of polyisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, 4,4'-diphenylether diisocyanate, 4,4'-[2,2-bis(4-phenoxyphenyl)propane]diisocyanate, and 2,2,4-trimethyl-hexamethylene diisocyanate. These may be used alone or in combination of two or more. Among these, at least one polyisocyanate selected from the group consisting of 2,4-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, and hexamethylene diisocyanate is preferred.

[0117] The crosslinking agent is preferably blended in an amount of 0.01 to 30 parts by mass, and more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the base resin (A). By adjusting the blending amount of the crosslinking agent as described above, the resin composition can reliably exhibit the functions exhibited by the addition of the crosslinking agent.

[0118] Plasticizers The adhesive layer 2 may contain a plasticizer. The plasticizer improves the flexibility of the adhesive layer 2. This allows the adhesive layer 2 to have excellent adhesion to, for example, the semiconductor substrate 7.

[0119] The plasticizer is not particularly limited, but examples thereof include phthalate ester plasticizers such as DOP (dioctyl phthalate), DBP (dibutyl phthalate), DIBP (diisobutyl phthalate), and DHP (diheptyl phthalate), aliphatic dibasic acid ester plasticizers such as DOA (di-2-ethylhexyl adipate), DIDA (diisodecyl adipate), and DOS (di-2-ethylhexyl sebacate), aromatic carboxylic acid ester plasticizers such as ethylene glycol benzoates, trimellitic acid ester plasticizers such as TOTM (trioctyl trimellitate), and adipate ester plasticizers, and these may be used alone or in combination of two or more.

[0120] The plasticizer is preferably blended in an amount of 0.1 to 5.0 parts by mass, more preferably 0.5 to 3.0 parts by mass, per 100 parts by mass of the base resin, thereby obtaining an adhesive layer 2 with excellent adhesion to the semiconductor substrate 7.

[0121] Other ingredients The resin composition forming the adhesive layer 2 may contain one or more of the following other components: conductive materials, tackifiers, antioxidants, adhesion adjusters, fillers, colorants, flame retardants, softeners, antioxidants, surfactants, etc.

[0122] 3.3.2.9. Thickness of adhesive layer, etc. The thickness of the adhesive layer 2 is not particularly limited, but is preferably 5 μm to 100 μm, more preferably 5 μm to 50 μm. By setting the thickness of the adhesive layer 2 within this range, it is possible to achieve an adhesive layer 2 that exhibits good adhesion to the semiconductor substrate 7 during the dicing process and good releasability during the pick-up process.

[0123] The adhesive layer 2 may be composed of a laminate (multilayer body) in which a plurality of layers composed of different resin compositions are laminated.

[0124] 4. Manufacturing method of adhesive tape Next, an example of a method for manufacturing the adhesive tape 100 will be described.

[0125] [1B] First, prepare the substrate 4. The method for producing the substrate 4 is not particularly limited, but examples thereof include common molding methods such as extrusion molding methods such as a calendar method, an inflation extrusion method, and a T-die extrusion method, and a wet casting method.

[0126] The upper surface of the substrate 4 may be previously subjected to a surface treatment such as corona treatment, chromic acid treatment, matte treatment, ozone exposure treatment, flame exposure treatment, high-voltage shock exposure treatment, ionizing radiation treatment, primer treatment, or anchor coat treatment, thereby improving the adhesion between the substrate 4 and the adhesive layer 2.

[0127] [2B] Next, adhesive layer 2 is formed on the upper surface of substrate 4. Adhesive layer 2 is formed by coating or spraying a liquid material made by dissolving a resin composition in a solvent to form a varnish on the upper surface of a film such as polyethylene terephthalate, then volatilizing the solvent to form a layer, and then transferring the layer to substrate 4.

[0128] The solvent is not particularly limited, but examples thereof include methyl ethyl ketone, acetone, toluene, ethyl acetate, dimethyl formaldehyde, etc., and one or more of these can be used in combination.

[0129] Furthermore, the liquid material can be applied or sprayed onto the substrate 4 using methods such as die coating, curtain die coating, gravure coating, comma coating, bar coating, and lip coating.

[0130] Thereafter, if necessary, a process for removing a part of the adhesive layer 2, a process for laminating a separator, etc. may be carried out. In this manner, the adhesive tape 100 is obtained.

[0131] 5. Effects of the above embodiment The pressure-sensitive adhesive tape 100 according to the embodiment includes a substrate 4 and a pressure-sensitive adhesive layer 2 laminated on one surface of the substrate 4, and is used to temporarily fix a semiconductor substrate 7 (substrate). The pressure-sensitive adhesive tape 100 is configured so that when a test piece 110 having a width of 25 mm and a length of 200 mm is subjected to a 90-degree slow peel test, the measured value is 1000 [mN / 25 mm] or more. The 90-degree slow peel test is a test in which the test piece 110 is attached to the mirror surface of a test plate 116 (silicon wafer), and then the test piece 110 is peeled in a 90-degree direction at a peel rate of 10 mm / min according to the test method specified in JIS Z 0237:2009.

[0132] With this configuration, even if the semiconductor substrate 7 is warped, it is possible to realize the adhesive tape 100 that can prevent the semiconductor substrate 7 and the adhesive layer 2 from peeling off from each other.

[0133] In addition, the adhesive layer 2 preferably contains a tackifier. This configuration imparts adhesiveness that can adequately resist a low-speed peel force to the adhesive layer 2. This reliably achieves an adhesive tape 100 whose measured value in a 90-degree low-speed peel test falls within the above range.

[0134] The adhesive layer 2 preferably contains a base resin (A), and the blending ratio of the tackifier to 100 parts by mass of the base resin (A) is preferably 10 parts by mass or more and 100 parts by mass or less.

[0135] With this configuration, it is possible to more reliably realize a pressure-sensitive adhesive tape 100 whose measured value in the 90-degree slow peel test falls within the above range.

[0136] The adhesive layer 2 preferably contains an acrylic resin as the base resin (A). Furthermore, the acrylic resin preferably contains a structure derived from an amide monomer.

[0137] The structure derived from the amide monomer introduces an amide bond into the side chain of the base resin (A). This amide bond is thought to provide unique adhesive properties based on intermolecular interactions. Therefore, by including a base resin (A) containing a structure derived from the amide monomer, adhesive properties that can adequately withstand low-speed peel forces are imparted to the adhesive layer 2. This ensures that the adhesive tape 100 has a measurement value in the 90-degree low-speed peel test that falls within the aforementioned range.

[0138] The acrylic resin has a main chain and a side chain containing an amide bond derived from an amide monomer.

[0139] With this configuration, even when the semiconductor substrate 7 is warped, it is possible to realize an adhesive layer 2 that has high adhesive strength before the energy ray irradiation process and sufficiently low adhesive strength after the energy ray irradiation process, while maintaining the function of suppressing peeling between the semiconductor substrate 7 and the adhesive layer 2. As a result, an adhesive tape 100 is obtained that can suppress peeling, dicing defects, and pickup defects caused by warping of the semiconductor substrate 7.

[0140] Furthermore, when the total amount of all monomer components constituting the acrylic resin is taken as 100 parts by mass, the content of the amide monomer is preferably 1 part by mass or more and 30 parts by mass or less.

[0141] This configuration provides the adhesive layer 2 with adhesiveness derived from the amide-based monomer that can adequately resist a low-speed peel force, thereby increasing the probability that the measured value in the 90-degree low-speed peel test will fall within the above-mentioned range. Furthermore, the measured value in the 180-degree high-speed peel test will also fall within the above-mentioned range.

[0142] The adhesive layer 2 may also contain a curable resin (B) that is cured by irradiation with energy rays E.

[0143] According to this configuration, the adhesive strength of the adhesive layer 2 after the energy ray irradiation treatment can be effectively reduced.

[0144] Furthermore, the pressure-sensitive adhesive tape 100 according to the embodiment is configured so that when a test piece 110 having a width of 25 mm and a length of 200 mm is subjected to a 180-degree high-speed peel test, the measured value satisfies 2500 [mN / 25 mm] or more. The 180-degree high-speed peel test is a test in which the test piece 110 is attached to the mirror surface of a test plate 116 (silicon wafer), and then the test piece 110 is peeled in a 180-degree direction at a peel speed of 300 mm / min according to the test method specified in JIS Z 0237:2009.

[0145] In the 180-degree high-speed peel test, the peeling direction is 180 degrees and the peeling speed is high, so that it is possible to quantitatively evaluate the stability of fixing the semiconductor substrate 7 during, for example, a dicing process that generates vibrations, etc. Therefore, when the measured value in the 180-degree high-speed peel test is within the above range, it is possible to realize an adhesive tape 100 that can stably fix the semiconductor substrate 7 even if the semiconductor substrate 7 is warped.

[0146] Although the pressure-sensitive adhesive tape of the present invention has been described above, the present invention is not limited to the above-described embodiment.

[0147] For example, each layer of the pressure-sensitive adhesive tape of the present invention may contain a component other than the components described in the above embodiment. Furthermore, the pressure-sensitive adhesive tape of the present invention may have an optional layer added to the layer configuration described in the above embodiment. In this case, the location of the additional layer is not particularly limited, and may be on the upper surface of the pressure-sensitive adhesive layer, on the lower surface of the substrate, or between the pressure-sensitive adhesive layer and the substrate. Furthermore, the substrate may be composed of multiple layers.

[0148] Furthermore, the substrate to be temporarily fixed by the pressure-sensitive adhesive tape of the present invention is not limited to the above-mentioned semiconductor substrate (semiconductor wafer), and may be, for example, a glass substrate such as soda-lime glass, borosilicate glass, or quartz glass, a ceramic substrate such as alumina, silicon nitride, or titanium oxide, a resin substrate such as acrylic, polycarbonate, or rubber, a single crystal substrate such as quartz or sapphire, or a metal plate, etc. Furthermore, members such as chips obtained by dividing a wafer are also included in the substrate to be temporarily fixed by the pressure-sensitive adhesive tape. [Example]

[0149] Next, specific examples of the present invention will be described, but the present invention is not limited to the descriptions of these examples.

[0150] 6. Preparation of Adhesive Tape An adhesive tape was prepared using the following materials.

[0151] 6.1. Preparation of raw materials Table 1 shows the base resin, curable resin, tackifier, photopolymerization initiator and crosslinking agent used in preparing the adhesive layer.

[0152] An acrylic copolymer (base resin a1) was obtained by copolymerizing 85 parts by mass of butyl acrylate, 13 parts by mass of methyl methacrylate, 1 part by mass of hydroxyethyl acrylate, and 0.6 parts by mass of acrylic acid.

[0153] An acrylic copolymer (base resin a2-1) was obtained by copolymerizing 66.2 parts by mass of butyl acrylate, 28.3 parts by mass of methyl methacrylate, 3.1 parts by mass of hydroxyethyl acrylate, 1.8 parts by mass of dimethylacrylamide, and 0.6 parts by mass of acrylic acid.

[0154] An acrylic copolymer (base resin a2-2) was obtained by copolymerizing 66.2 parts by mass of butyl acrylate, 26.6 parts by mass of methyl methacrylate, 3.1 parts by mass of hydroxyethyl acrylate, 3.5 parts by mass of dimethylacrylamide, and 0.6 parts by mass of acrylic acid.

[0155] An acrylic copolymer (base resin a2-3) was obtained by copolymerizing 66.2 parts by mass of butyl acrylate, 24.8 parts by mass of methyl methacrylate, 3.1 parts by mass of hydroxyethyl acrylate, 5.3 parts by mass of dimethylacrylamide, and 0.6 parts by mass of acrylic acid.

[0156] An acrylic copolymer (base resin a2-4) was obtained by copolymerizing 66.2 parts by mass of butyl acrylate, 23.0 parts by mass of methyl methacrylate, 3.1 parts by mass of hydroxyethyl acrylate, 7.1 parts by mass of dimethylacrylamide, and 0.6 parts by mass of acrylic acid.

[0157] An acrylic copolymer (base resin a2-5) was obtained by copolymerizing 66.2 parts by mass of butyl acrylate, 21.3 parts by mass of methyl methacrylate, 3.1 parts by mass of hydroxyethyl acrylate, 8.8 parts by mass of dimethylacrylamide, and 0.6 parts by mass of acrylic acid.

[0158] In addition, when each base resin is an amide bond-introduced acrylic resin having an amide bond in the side chain, a circle is marked in the "amide bond-introduced type" column in Table 1, and when an amide bond is not introduced in the side chain, an × is marked.

[0159] Furthermore, the main monomer component, glass transition temperature Tg, and weight-average molecular weight Mw of each base resin are shown in Table 1. The main monomer component refers to the component with the highest content by mass among all monomer components. Each base resin was synthesized by changing the blend and molecular weight of the monomer components so that these physical properties would achieve the values ​​shown in Table 1. Among the symbols representing the main monomer components, BA stands for butyl acrylate.

[0160] Table 1 also shows the number of functional groups in the curable resin b1. Furthermore, the tackifier c1 is a polymerized rosin ester tackifier represented by the above formula (2).

[0161] [Table 1]

[0162] 6.2. Preparation of adhesive layer First, a liquid material was prepared by blending the raw materials shown in Table 2 in the prescribed ratios. Next, this liquid material was bar-coated onto a polyethylene terephthalate film so that the thickness after drying would be the value shown in Table 2. The resulting coating was dried at 80°C for 1 minute and transferred to the substrate shown in Table 2 to obtain an adhesive layer.

[0163] The thickness of the substrate 1 used to prepare the adhesive tape is shown in Table 2. The constituent materials of the substrate 1 were FS2011DG-2 (PP) / H1062 (elastomer) = 60 / 40 (mass ratio).

[0164] In Table 2, examples corresponding to the present invention are labeled "Examples," and examples not corresponding to the present invention are labeled "Comparative Examples."

[0165] 7. Evaluation of adhesive tapes Next, the produced pressure-sensitive adhesive tapes were evaluated for the following items.

[0166] 7.1. Peeling after attachment to warped substrate First, a 4-inch silicon wafer was prepared. A resin layer had been formed on the entire surface of this silicon wafer opposite the mirrored surface. As a result, the silicon wafer had warped to the extent that the mirrored surface was convex, causing a maximum lift of 3.5 mm at the edge. The lift refers to the distance between the raised edge and the flat surface when the silicon wafer is placed on the flat surface.

[0167] Next, the mirror surface of a 4-inch silicon wafer was attached to the adhesive tape of each example and comparative example. After that, the adhesive tape side was quickly attached to the chuck table. This fixed the adhesive tape and the silicon wafer to the chuck table so that the silicon wafer was corrected to be flat.

[0168] After leaving it in this state for 10 minutes, the adhesive tape and silicon wafer were released from the clamping position and left for 24 hours in an environment with an ambient temperature of 23°C. The interface between the silicon wafer (warped substrate) and the adhesive tape was then visually inspected for peeling. The observation results were evaluated according to the following evaluation criteria. The evaluation results are shown in Table 2.

[0169] A: No peeling is observed B: Peeling is observed over less than 5% of the circumference of the silicon wafer. C: Peeling is observed over 5% or more of the circumference of the silicon wafer.

[0170] 7.2.Pickup ability First, a silicon wafer was attached to the adhesive tape of each example and comparative example. Next, a dicing process was performed to separate the wafer into individual pieces of 6 mm square, and then the wafer was irradiated with ultraviolet light at an intensity of 55 W / cm. 2 , UV irradiation amount: 200mJ / cm 2 The adhesive layer was cured by irradiating ultraviolet light under the conditions of

[0049] . Next, the adhesive tape was subjected to an expanding process, and then a pick-up process was carried out to pick up the silicon chips. By repeating the above process, 50 silicon chips were collected. The collected silicon chips were then observed under an optical microscope, and the observation results were evaluated in accordance with the following evaluation criteria. The evaluation results are shown in Table 2.

[0171] A: No pickup failure occurred B: 1 to 3 pickup failures occurred C: Four or more pickup failures occurred

[0172] [Table 2]

[0173] From the results shown in Table 2, the following was observed. When a warped silicon wafer was attached to adhesive tape whose measured values ​​in a 90-degree slow peel test were within the specified range, peeling due to the warping was suppressed.

[0174] By using adhesive tape with an adhesive layer containing a tackifier or an adhesive layer containing an amide bond-introduced acrylic resin, peeling caused by warping could be effectively suppressed.

[0175] It was confirmed that by using adhesive tape whose measured values ​​in the 180-degree high-speed peel test are within the specified range, dicing and pick-up processes can be performed smoothly and pick-up defects can be reduced. [Explanation of symbols]

[0176] 2 Adhesive layer 4 Base material 7. Semiconductor substrate 9 wafer rings 10 Semiconductor devices 17 Mold section 20 Semiconductor chips 21 terminals 23 Semiconductor chip body 30 Interposer 41 terminals 70 Bump 80 Sealing layer 81 Connection 100 adhesive tape 110 test specimens 112 Test adhesive layer 114 Test substrate 116 Test Plate 117 sides 121 Outer periphery 122 Central part 200 Dicer Table 300 Expandable Table 310 Extended Stage 320 Holding stand 400 Pickup Table E energy ray

Claims

1. An adhesive tape used to temporarily fix a substrate, comprising a base material and an adhesive layer laminated on one surface of the base material, A pressure-sensitive adhesive tape characterized in that when a test piece having a width of 25 mm and a length of 200 mm is attached to the mirror surface of a silicon wafer and then subjected to a 90-degree slow peel test in which the test piece is peeled in a 90-degree direction at a peel rate of 10 mm / min in a method conforming to the test method specified in JIS Z 0237:2009, the measured value satisfies 1000 [mN / 25 mm] or more.

2. The adhesive tape according to claim 1 , wherein the adhesive layer contains a tackifier.

3. The adhesive layer contains a base resin, The pressure-sensitive adhesive tape according to claim 2 , wherein a blending ratio of the tackifier to 100 parts by mass of the base resin is 10 parts by mass or more and 100 parts by mass or less.

4. The adhesive layer contains an acrylic resin as a base resin, The pressure-sensitive adhesive tape according to claim 1 , wherein the acrylic resin contains a structure derived from an amide monomer.

5. The pressure-sensitive adhesive tape according to claim 4 , wherein the acrylic resin has a main chain and a side chain containing an amide bond derived from the amide monomer.

6. The pressure-sensitive adhesive tape according to claim 4 or 5, wherein the content of the amide monomer is 1 part by mass or more and 30 parts by mass or less when the total amount of all monomer components constituting the acrylic resin is 100 parts by mass.

7. The adhesive tape according to claim 2 , wherein the adhesive layer contains a curable resin that is cured by irradiation with energy rays.

8. 2. The pressure-sensitive adhesive tape according to claim 1, wherein when a test piece set to a width of 25 mm and a length of 200 mm is attached to the mirror surface of a silicon wafer and then subjected to a 180-degree high-speed peel test in which the test piece is peeled in a 180-degree direction at a peel rate of 300 mm / min according to the test method specified in JIS Z 0237:2009, the measured value is 2500 mN / 25 mm or more.

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