Adhesive tape, and method for applying adhesive tape.

Abstract

To provide an adhesive tape that can maintain appropriate adhesive strength even when in contact with a processing liquid. [Solution] The adhesive tape of the embodiment of the present invention comprises a base material and an adhesive layer composed of an adhesive, and is used in a manufacturing method that includes contact with a processing liquid. The relative energy difference of this adhesive with respect to ethylene glycol, based on the Hansen solubility parameter, is 1.6 or more.

Description

[Technical Field]

[0001] The present invention relates to adhesive tape and a method for selecting adhesive tape. [Background technology]

[0002] Adhesive tapes are widely used for surface protection and fixing of adherends. For example, in the semiconductor wafer processing process, they are used to properly hold the semiconductor wafer, which is the adherend, during the backgrinding and dicing processes. Since adhesive tapes used in semiconductor wafer processing are peeled off from the semiconductor wafer after use, adhesive tapes with re-peelability are preferably used (Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-31620 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] In the semiconductor wafer manufacturing process, adhesive tape and semiconductor wafers are laminated together and subjected to processing steps. For example, in the dicing process, sufficient adhesive strength is required to suppress chip flying off of the wafer fragments when the wafer is cut with a blade. In the dicing process, a cooling liquid such as a coolant is sometimes used to suppress blade wear. However, contact with the cooling liquid can change the adhesive strength of the adhesive layer, preventing it from exhibiting the required adhesive strength and making it impossible to properly hold the semiconductor wafer. Therefore, there is a need for adhesive tape that can maintain appropriate adhesive strength even when in contact with a cooling liquid. [Means for solving the problem]

[0005] 1. The adhesive tape of the embodiment of the present invention comprises a base material and an adhesive layer composed of an adhesive, and is used in a manufacturing method that includes contact with a processing liquid, wherein the relative energy difference of the adhesive with respect to ethylene glycol, based on the Hansen solubility parameter, is 1.6 or more. 2. In the adhesive tape described in item 1 above, the adhesive strength of the adhesive layer before ultraviolet irradiation may be 3.5 N / 20 mm or more. 3. The rate of reduction in anchoring force determined by ethylene glycol contact evaluation of the adhesive tape described in 1 or 2 above may be less than 4%. 4. In the adhesive tape described in any of items 1 to 3 above, the adhesive contains a base polymer, and the content of monomer components having polar groups in the monomer composition used for polymerization of the base polymer may be 50% by weight or less. 5. In the adhesive tape described in item 4 above, the adhesive is an ultraviolet-curable adhesive, and the base polymer may be a polymer having polymerizable carbon-carbon double bonds. 6. In the adhesive tape described in 4 or 5 above, the adhesive may contain 0.1 parts by weight or more of a crosslinking agent per 100 parts by weight of the base polymer. 7. In the adhesive tape described in any of items 1 to 6 above, the adhesive strength before ultraviolet irradiation may be 5 N / 20 mm or more. 8. In the adhesive tape described in any of items 5 to 7 above, the adhesive strength after ultraviolet irradiation may be 0.5 N / 20 mm or less. 9. Any adhesive tape described in item 1 to 8 above may be used for semiconductor processing. 10. In another aspect of the present invention, a method for selecting an adhesive tape is provided. This selection method includes measuring the Hansen solubility parameter of a processing solution used in a semiconductor wafer processing step, measuring the Hansen solubility parameter of an adhesive used in the adhesive layer of an adhesive tape, calculating a relative energy difference from the Hansen solubility parameter of the processing solution and the Hansen solubility parameter of the adhesive, and selecting an adhesive whose relative energy difference is an arbitrary value. 11. The method for selecting the adhesive tape according to 10 above may include selecting an adhesive having a relative energy difference of 0.9 or more. 12. The method for selecting the adhesive tape according to 10 above may include selecting an adhesive having ethylene glycol as the treatment liquid and a relative energy difference of 1.6 or more.

Advantages of the Invention

[0006] According to an embodiment of the present invention, an adhesive tape capable of maintaining an appropriate adhesive force even when used in a step of contacting a treatment liquid such as a coolant liquid and a cleaning liquid can be provided. As a result, defects due to changes in the adhesive force in the step of using the adhesive tape (for example, chip flying in the dicing step) can be suppressed. Further, according to the method for selecting an adhesive tape of an embodiment of the present invention, an adhesive suitable for use in the step of contacting with a treatment liquid can be selected.

Brief Description of the Drawings

[0007] [Figure 1] It is a schematic cross-sectional view of an adhesive tape according to one embodiment of the present invention.

Modes for Carrying Out the Invention

[0008] A. Overall Configuration of Adhesive Tape The adhesive tape according to an embodiment of the present invention includes an adhesive layer composed of a substrate and an adhesive. This adhesive tape is used in a manufacturing method that includes contact with a processing liquid (e.g., a coolant). In the semiconductor wafer manufacturing process, when the adhesive tape is brought into contact with processing liquids such as coolant and cleaning liquids, the adhesive strength of the adhesive layer may change. For example, if the adhesive strength decreases, it may become difficult to properly hold the adherend. The adhesive tape according to an embodiment of the present invention has a relative energy difference (RED) of 1.6 or more based on the Hansen solubility parameter of the adhesive constituting the adhesive layer with respect to ethylene glycol. Ethylene glycol is a typical solvent used in the semiconductor wafer manufacturing process. After diligent research, it was found that there is a high correlation between the behavior with respect to processing liquids and tests using ethylene glycol. An adhesive tape having an adhesive layer composed of an adhesive with a RED of 1.6 or more with respect to ethylene glycol can properly hold the adherend even when subjected to a process that involves contact with a processing liquid. As a result, for example, even when brought into contact with a coolant, which is a processing liquid, in the semiconductor wafer dicing process, the occurrence of chip breakage can be suppressed. In this specification, "processing liquid" refers to a liquid actually used in semiconductor wafer processing processes such as dicing (e.g., coolant). Ethylene glycol can be used, for example, as the main component of the coolant.

[0009] Figure 1 is a schematic cross-sectional view of an adhesive tape according to an embodiment of the present invention. The adhesive tape 100 comprises a base material 20 and an adhesive layer 10 in that order. The adhesive layer 10 is formed using an adhesive having a RED of 1.6 or more relative to ethylene glycol. Using such an adhesive can suppress changes in adhesive strength even when in contact with a processing liquid. The adhesive tape 100 may further include any suitable layer. For example, an intermediate layer (not shown) may be formed between the base material 20 and the adhesive layer 10. When an intermediate layer is included, adhesion to an adherend having an uneven surface can be improved. It may also further include an antistatic layer. When other layers such as an intermediate layer and an antistatic layer are further included, it is preferable that the RED of the materials forming these layers has a RED of 1.6 or more relative to ethylene glycol.

[0010] As described above, the relative energy difference of the adhesive constituting the adhesive layer with respect to ethylene glycol, based on the Hansen solubility parameter, is 1.6 or greater. The Hansen solubility parameter is represented by a vector plotted in three-dimensional space, obtained by dividing the Hildebrand solubility parameter into three components: dispersion force (δd), permanent dipole intermolecular force (δp), and hydrogen bonding force (δh). Substances with similar vectors can be judged to have high solubility towards each other. In other words, the similarity of solubility can be determined from the distance between their HSP values ​​(HSP distance). The definition and calculation of the Hansen solubility parameter (HSP) are described in Charles M. Hansen, "Hansen Solubility Parameters: A Users Handbook" (CRC Press, 2007). There are known HSP values ​​for various resins and solvents, and these can be used as is, or values ​​calculated using the computer software HSPiP (Hansen Solubility Parameters in Practice) can be used. HSPiP also includes a database of resins and solvents.

[0011] In this specification, the HSP of adhesives shall be the HSP value measured by the following method. First, a solvent for which the HSP is known (e.g., a solvent for which literature values ​​exist) and the sample to be measured for HSP shall be placed in a sealable container so that the concentration of the sample is 0.8 parts by weight / 10 mL for adhesives, and 8 parts by weight / 10 mL for solvents. If the sample is an adhesive, the solid content shall be used to match the above concentration. Next, the container shall be handshook to thoroughly mix the target substance and the solvent. Then, the container shall be left to stand for 24 hours at room temperature (23°C). After that, the container shall be visually observed. For adhesives, if precipitate or aggregates are present in the container, it shall be judged as insoluble; if no precipitate or aggregates are present, it shall be judged as dissolved. This test shall be performed for the 20 types of solvents listed in Table 1. From the obtained test results, a sphere (Hansen sphere) shall be drawn in Hansen space that includes the coordinates of the solvent in which the adhesive was dissolved, but does not include the coordinates of the solvent in which the target substance was not dissolved. The coordinates of the center of the drawn Hansen sphere indicate the HSP value of the adhesive. The HSP value is calculated using the Hansen solubility parameter calculation software HSPiP (HSPiP 5th Edition Ver. 5.3.03, manufactured by Hansen-Solublity.com). Note that the dispersion force (δd), permanent dipole intermolecular force (δp), and hydrogen bonding force (δh) of the solvent listed in Table 1 are the values ​​registered in HSPiP 5th Edition Ver. 5.3.03. [Table 1]

[0012] Next, the dispersion power (δd) of ethylene glycol registered in the software s ), permanent dipole intermolecular force (δp s ), and hydrogen bonding force (δh s ) and the dispersion force of the adhesive (δd ad ), permanent dipole intermolecular force (δp ad ), and hydrogen bonding force (δh ad The coordinate distance Ra between ethylene glycol and the adhesive is calculated from the following formula (1). Ra=[4×(δd s-δd ad ) 2 +(δp s -δp ad ) 2 +(δh s -δh ad ) 2 1 / 2 (1)

[0013] Next, based on the coordinate distance Ra between the obtained ethylene glycol and the adhesive and the radius R of the Hansen sphere of the adhesive, the relative energy difference (RED) based on the Hansen solubility parameter of the adhesive with respect to ethylene glycol is calculated by the following formula (2). ad From this, the relative energy difference (RED) based on the Hansen solubility parameter of the adhesive with respect to ethylene glycol is calculated by the following formula (2). RED = Ra / R ad (2)

[0014] The RED of the adhesive with respect to ethylene glycol is 1.6 or more, preferably 1.65 or more, more preferably 1.8 or more, and still more preferably 2.0 or more. If the RED of the adhesive with respect to ethylene glycol is within the above range, even when an adhesive tape is used in a manufacturing method including a step of contacting with a treatment liquid, appropriate adhesive strength can be maintained. As a result, defects due to changes in adhesive strength in the step of using the adhesive tape (for example, chip flying in the dicing step) can be suppressed. The larger the RED of the adhesive with respect to ethylene glycol, the more preferable. The RED of the adhesive with respect to ethylene glycol is, for example, 10 or less, preferably 8 or less, and more preferably 5 or less.

[0015] ​The adhesive tape of the embodiment of the present invention preferably has an anchoring force reduction rate of less than 4% in contact evaluation with ethylene glycol, more preferably 3% or less, even more preferably 2% or less, and even more preferably 1% or less. The lower the reduction rate, the better, and it may even be 0% (i.e., no change in anchoring force). In this specification, the anchoring force reduction rate in contact evaluation with ethylene glycol refers to the value measured by the following method. Two samples are taken from a laminate of adhesive tape having a base material and an adhesive layer and a release liner, cut to a width of 20 mm and a length of 150 mm. The adhesive tape used has been stored in a room at 25°C for at least 2 hours. The release liner is peeled off from one of the samples. Next, the adhesive layer of a commercially available adhesive tape (for example, Nitto Denko Corporation, product name "BT-315") is attached to the adhesive layer side of the sample, and left to stand at 25°C for 30 minutes. Subsequently, a T-type peel test is performed using a tensile testing machine (e.g., Shimadzu Corporation, product name "AG-50kNXplus") at a peeling speed of 300 mm / min, and the anchoring force (N / 20 mm) is measured. The other sample is immersed in ethylene glycol at room temperature for 10 minutes. Then, the sample is removed from the ethylene glycol and immersed in pure water at room temperature for 10 minutes. Next, the sample is air-dried at room temperature for 24 hours. Then, the adhesive layer of a commercially available adhesive tape (e.g., Nitto Denko Corporation, product name "BT-315", adhesive strength 15.0 N / 20 mm) is attached to the adhesive layer side of the sample, and it is left to stand at 25°C for 30 minutes. Subsequently, a T-type peel test is performed using a tensile testing machine (e.g., Shimadzu Corporation, product name "AG-50kNXplus") at a peeling speed of 300 mm / min, and the anchoring force (N / 20 mm) is measured. The rate of decrease is calculated using the following formula based on the anchoring force of the sample that was not immersed in ethylene glycol and the anchoring force of the sample that was immersed in ethylene glycol. Anchoring force reduction rate (%) = {(Anchoring force of sample not immersed in ethylene glycol (N / 20mm)) - (Anchoring force of sample immersed in ethylene glycol (N / 20mm))} / (Anchoring force of sample not immersed in ethylene glycol (N / 20mm)) × 100

[0016] The anchoring force of the adhesive tape measured by the above method (anchoring force of adhesive tape not immersed in ethylene glycol) is preferably 7 N / 20 mm or more, more preferably 8 N / 20 mm or more, even more preferably 10 N / 20 mm or more, and particularly preferably 12 N / 20 mm or more. If the anchoring force is within the above range, peeling of the adhesive tape before the peeling process can be suppressed. The anchoring force is, for example, 30 N / 20 mm or less.

[0017] The adhesive strength (adhesion to the silicon wafer) of the adhesive tape before UV irradiation (hereinafter also referred to as "before UV") is preferably 3.5 N / 20 mm or more, more preferably 4.5 N / 20 mm or more, and even more preferably 5 N / 20 mm or more. If the adhesive strength of the adhesive tape to the silicon wafer before UV is within the above range, it will have sufficient adhesion to the substrate, and chip flying can be suppressed when the adhesive tape is used as a dicing tape. Alternatively, the adhesive strength to the silicon wafer before UV is, for example, 25 N / 20 mm or less. In this specification, the adhesive strength to the silicon wafer before UV irradiation refers to the adhesive strength measured by the following method. The adhesive tape is cut to a width of 20 mm and a length of 150 mm. The cutting is done so that the MD direction of the adhesive tape is in the length direction. The cut adhesive tape and the silicon wafer are bonded together, and the adhesive tape is pressed down by moving a 2 kg hand roller back and forth once in an atmosphere of 23°C, and left to stand for 30 minutes. Subsequently, a 180° peel test is performed at 23°C, 50% RH atmosphere, and a peeling speed of 50 mm / min to measure the force required to peel off the adhesive tape. The adhesive strength is then measured using a tensile testing machine (for example, Shimadzu Corporation, product name "AG-50kNXplus").

[0018] The adhesive strength (adhesion to the silicon wafer) of the heated adhesive tape before UV irradiation (hereinafter also referred to as "before UV") is preferably 4.5 N / 20 mm or more, and more preferably 5 N / 20 mm or more. If the adhesive strength of the heated adhesive tape to the silicon wafer before UV is within the above range, it will have sufficient adhesion to the adherend, and chip flying can be suppressed when the adhesive tape is used as a dicing tape. Alternatively, the adhesive strength of the heated adhesive tape to the silicon wafer before UV is, for example, 25 N / 20 mm or less. In this specification, the adhesive strength of the heated adhesive tape to the silicon wafer before UV irradiation refers to the adhesive strength measured by the following method. The adhesive tape is cut to a width of 20 mm and a length of 150 mm. The cutting is done so that the MD direction of the adhesive tape is in the length direction. The cut adhesive tape and the silicon wafer are bonded together, and the adhesive tape is pressed down by moving a 2 kg hand roller back and forth once in an atmosphere of 23°C, and left to stand for 30 minutes. Next, the adhesive tape is placed in an oven and heated at 75°C for 3 minutes, after which it is removed from the oven and left to stand at room temperature for 30 minutes. Then, a 180° peel test is performed at 23°C, 50% RH atmosphere, and a peeling speed of 50 mm / min to measure the force required to peel the adhesive tape, and the adhesive strength is measured using a tensile testing machine (for example, Shimadzu Corporation, product name "AG-50kNXplus").

[0019] The adhesive strength (adhesion to the silicon wafer) of the adhesive tape after ultraviolet irradiation (hereinafter also referred to as "after UV") is preferably 0.5 N / 20 mm or less, and more preferably 0.4 N / 20 mm or less. If the adhesive strength of the adhesive tape to the silicon wafer after UV is within the above range, the wafer fragments obtained in the pickup process or scratching process can be easily recovered from the adhesive tape. Furthermore, the adhesive strength to the silicon wafer after UV is, for example, 0.05 N / 20 mm or more. In this specification, the adhesive strength to the silicon wafer before ultraviolet irradiation refers to the adhesive strength measured by the following method: The adhesive tape is cut to a width of 20 mm and a length of 150 mm. The cutting is performed so that the MD direction of the adhesive tape is in the length direction. The cut adhesive tape and the silicon wafer are bonded together, and the adhesive tape is pressed down by moving a 2 kg hand roller back and forth once in an atmosphere of 23°C, and left to stand for 30 minutes. Then, ultraviolet (UV) light is applied to an integrated light amount of 460 mJ / cm². 2 Irradiation is performed from the adhesive layer side to achieve a value equivalent to 365nm. Subsequently, a 90° peel test is conducted at 23°C, 50%RH atmosphere, and a peeling speed of 300mm / min to measure the force required to peel the adhesive tape, and the adhesive strength is measured using a tensile testing machine (for example, Shimadzu Corporation, product name "AG-50kNXplus").

[0020] The adhesive strength (adhesion to the silicon wafer) of the heated adhesive tape after UV irradiation (hereinafter also referred to as "after UV") is preferably 0.5 N / 20 mm or less, and more preferably 0.45 N / 20 mm or less. If the adhesive strength of the heated adhesive tape to the silicon wafer after UV irradiation is within the above range, the wafer fragments obtained in the pickup process or scratching process can be easily recovered from the adhesive tape. Furthermore, the adhesive strength of the heated adhesive tape to the silicon wafer after UV irradiation is, for example, 0.05 N / 20 mm or more. In this specification, the adhesive strength of the heated adhesive tape to the silicon wafer before UV irradiation refers to the adhesive strength measured by the following method. The adhesive tape is cut to a width of 20 mm and a length of 150 mm. The cutting is performed so that the MD direction of the adhesive tape is in the length direction. The cut adhesive tape is pressed down by moving a 2 kg hand roller back and forth once in an atmosphere of 23°C, and left to stand for 30 minutes. Next, the adhesive tape is placed in an oven and heated at 75°C for 3 minutes, then removed from the oven and left to stand at room temperature for 30 minutes. Then, ultraviolet (UV) light is applied until the accumulated light intensity reaches 460 mJ / cm². 2 Irradiation is performed from the adhesive layer side to achieve a value equivalent to 365nm. Subsequently, a 90° peel test is conducted at 23°C, 50%RH atmosphere, and a peeling speed of 300mm / min to measure the force required to peel the adhesive tape, and the adhesive strength is measured using a tensile testing machine (for example, Shimadzu Corporation, product name "AG-50kNXplus").

[0021] The thickness of the adhesive tape in the embodiment of the present invention can be set to any suitable thickness. Preferably, the thickness of the adhesive tape is 30 μm to 400 μm, more preferably 40 μm to 300 μm, and even more preferably 50 μm to 200 μm.

[0022] B. Base material The base material can be composed of any suitable resin. Specific examples of resins constituting the base material include polyester resins such as polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), and polybutylene naphthalate (PBN); polyolefin resins such as ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, polyethylene, polypropylene, and ethylene-propylene copolymer; polyvinyl alcohol, polyvinylidene chloride, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyamide, polyimide, celluloses, fluororesins, polyethers, polystyrene resins such as polystyrene; polycarbonate, polyethersulfone, and polyetheretherketone. Preferably, polyolefin resins, polyvinyl chloride resins, and polyimide resins are used. Using these resins can suppress the generation of cutting debris and whiskers when cutting the adhesive tape. Furthermore, because ultraviolet light is transmitted, an adhesive layer can be formed using an active energy ray curing adhesive such as an ultraviolet curing adhesive to provide an adhesive tape with easy peelability.

[0023] The base material may further contain other components, to the extent that it does not impair the effects of the present invention. Examples of other components include antioxidants, ultraviolet absorbers, light stabilizers, heat stabilizers, and antistatic agents. The type and amount of other components used can be any appropriate amount depending on the purpose.

[0024] The thickness of the substrate is preferably 30 μm to 200 μm, more preferably 40 μm to 180 μm, and even more preferably 45 μm to 180 μm.

[0025] C.Adhesive layer The adhesive layer only needs to be formed with an adhesive having a RED of 1.6 or higher relative to ethylene glycol, and any suitable adhesive can be used. Examples include acrylic adhesives, rubber adhesives, silicone adhesives, and polyvinyl ether adhesives. Preferably, an acrylic adhesive is used. Using an acrylic adhesive makes it easy to adjust the storage modulus and tensile modulus of the adhesive layer, and can also yield an adhesive tape with an excellent balance between adhesive strength and release properties. Furthermore, contamination of semiconductor wafers by components derived from the adhesive can be reduced.

[0026] In one embodiment, an ultraviolet-curable adhesive is used as the adhesive. With an ultraviolet-curable adhesive, the adhesive layer can be cured by irradiating it with ultraviolet light, thereby suppressing adhesive residue on the adherend. Furthermore, damage to the adherend when peeling off the adhesive tape can be suppressed. Any suitable adhesive can be used as the ultraviolet-curable adhesive. For example, it may be an adhesive to which an ultraviolet-curable monomer and / or oligomer has been added, or it may be an adhesive using a polymer having a polymerizable carbon-carbon double bond as the base polymer, or a combination of these may be used. Preferably, an adhesive using a polymer having a polymerizable carbon-carbon double bond as the base polymer is used. Using such an adhesive can suppress adhesive residue on the adherend.

[0027] When using an adhesive that utilizes a polymer in which polymerizable carbon-carbon double bonds are introduced into the side chains and / or terminals, the base polymer used is a polymer that has polymerizable carbon-carbon double bonds introduced into the side chains and / or terminals and is also adhesive.

[0028] C-1. Base Polymer The base polymer can be obtained by carrying out a polymerization reaction using a monomer composition containing any suitable monomer. The content of monomer components having polar groups in the monomer composition used for polymerization of the base polymer is preferably 50% by weight or less, and more preferably 30% by weight or less. If the content of monomer components having polar groups is within the above range, changes in adhesive strength can be suppressed even when the adhesive layer comes into contact with the processing liquid. Furthermore, among the HSP values ​​of the adhesive, the permanent dipole intermolecular force (δp) is also important. ad The RED value with ethylene glycol can be adjusted to 1.6 or higher by adjusting the ) ratio. The content of monomer components having polar groups in the monomer composition is preferably 10% by weight or more. If the content of monomers having polar groups is 10% by weight or more, the cohesive force may be improved.

[0029] Any suitable monomer can be used as the monomer containing a polar group. Examples include hydroxyl group-containing monomers, carboxyl group-containing monomers, nitrogen-containing monomers, etc. The monomer containing a polar group may have one polar group or two or more polar groups (for example, a hydroxyl group and a nitrogen-containing group). Only one polar group-containing monomer may be used, or two or more may be used in combination.

[0030] Any suitable monomer can be used as the hydroxyl group-containing monomer. Specifically, examples include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and N-(2-hydroxyethyl)acrylamide. Only one hydroxyl group-containing monomer may be used, or two or more may be used in combination.

[0031] Any suitable monomer can be used as the carboxyl group-containing monomer. Specifically, examples include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, etc. Only one carboxyl group-containing monomer may be used, or two or more may be used in combination.

[0032] Any suitable monomer can be used as the nitrogen-containing monomer. Specifically, examples include N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinylmorpholine, (meth)acryloylmorpholine, N-vinyl carboxylic acid amides, N-vinylcaprolactam, N-(2-hydroxyethyl)acrylamide, N,N-dimethylacrylamide, etc. Only one nitrogen-containing monomer may be used, or two or more may be used in combination.

[0033] Other than monomer components having polar groups, any suitable monomer can be used. For example, esters of acrylic acid or methacrylic acid having a linear or branched alkyl group can be used. The linear or branched alkyl group is preferably an alkyl group having 30 or fewer carbon atoms, more preferably an alkyl group having 1 to 20 carbon atoms, and even more preferably an alkyl group having 4 to 18 carbon atoms. Specific examples of alkyl groups include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, heptyl group, cyclohexyl group, 2-ethylhexyl group, octyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, lauryl group, tridecyl group, tetradecyl group, stearyl group, octadecyl group, dodecyl group, and the like.

[0034] The monomer composition may contain any other suitable monomers. Other monomers include, for example, carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; acid anhydride monomers such as maleic anhydride and itaconic anhydride; (meth)acrylate 2-hydroxyethyl, (meth)acrylate 2-hydroxypropyl, (meth)acrylate 4-hydroxybutyl, (meth)acrylate 6-hydroxyhexyl, (meth)acrylate 8-hydroxyoctyl, (meth)acrylate 10-hydroxydecyl, (meth)acrylate 12-hydroxylauryl, (4-hydroxy Examples of functional group-containing monomers include hydroxyl group-containing monomers such as hydroxymethylcyclohexyl)-methyl acrylate, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether; sulfonic acid group-containing monomers such as styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid; and phosphate group-containing monomers such as 2-hydroxyethyl acryloyl phosphate. Using functional group-containing monomers can yield polymers in which radiation-polymerizable carbon-carbon double bonds are readily introduced. The content of functional group-containing monomers in the monomer composition used for polymerization of the base polymer is preferably 4% to 40% by weight, and more preferably 6% to 30% by weight, based on 100 parts by weight of the total monomer components.

[0035] The weight-average molecular weight of the base polymer is preferably 100,000 or more, more preferably 300,000 or more, even more preferably 500,000 or more, and particularly preferably 600,000 to 3,000,000. Within this range, it is possible to obtain an adhesive tape that suppresses the bleeding of low molecular weight components and reduces contamination of the adherend by foreign matter. The molecular weight distribution (weight-average molecular weight / number-average molecular weight) of the base polymer is preferably 1 to 20, more preferably 3 to 10. By using a base polymer with a narrow molecular weight distribution, it is possible to prevent the bleeding of low molecular weight components and obtain an adhesive tape with low contamination. The weight-average molecular weight and number-average molecular weight can be determined by gel permeation chromatography (solvent: tetrahydrofuran, polystyrene equivalent).

[0036] Base polymers having polymerizable carbon-carbon double bonds can be obtained by any suitable method. For example, they can be obtained by reacting (e.g., condensation reaction, addition reaction) a polymer obtained by any suitable polymerization method with a compound having polymerizable carbon-carbon double bonds. Specifically, when an acrylic polymer is used as the base polymer, an acrylic polymer (copolymer) having constituent units derived from monomers having any suitable functional groups can be polymerized in any suitable solvent, and then the functional groups of the acrylic polymer can be reacted with a compound having polymerizable carbon-carbon double bonds that can react with the functional groups to obtain an acrylic polymer into which polymerizable carbon-carbon double bonds have been introduced. The amount of the compound having polymerizable carbon-carbon double bonds to be reacted is preferably 4 to 30 parts by weight, more preferably 4 to 20 parts by weight, per 100 parts by weight of the acrylic polymer. Any suitable solvent can be used as the solvent, for example, various organic solvents such as ethyl acetate, methyl tyl ketone, and toluene.

[0037] When a polymer and a compound having a polymerizable carbon-carbon double bond are reacted as described above, it is preferable that both the polymer and the compound having a polymerizable carbon-carbon double bond have functional groups that can react with each other. Examples of functional group combinations include carboxyl group / epoxy group, carboxyl group / aziridine group, and hydroxyl group / isocyanate group. Among these functional group combinations, the combination of a hydroxyl group and an isocyanate group is preferred due to the ease of reaction tracking.

[0038] Examples of compounds having polymerizable carbon-carbon double bonds include 2-isocyanate ethyl methacrylate, methacryloisocyanate, 2-methacryloyloxyethyl isocyanate (2-isocyanate ethyl methacrylate), and m-isopropenyl-α,α-dimethylbenzyl isocyanate.

[0039] As described above, a base polymer having a polymerizable carbon-carbon double bond is used as the base polymer and can function as an ultraviolet-curable adhesive. In one embodiment, a base polymer having a polymerizable carbon-carbon double bond may be used in combination with an ultraviolet-curable monomer and / or oligomer. By using an ultraviolet-curable monomer and / or oligomer in combination, the tackiness of the adhesive layer can be adjusted as appropriate. Any suitable monomer or oligomer can be used as the ultraviolet-curable monomer and oligomer. Examples of ultraviolet-curable monomers include urethane (meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and 1,4-butanediol di(meth)acrylate. Examples of UV-curable oligomers include urethane-based oligomers, polyether-based oligomers, polyester-based oligomers, polycarbonate-based oligomers, and polybutadiene-based oligomers. Preferably, the oligomers used have a molecular weight of approximately 100 to 30,000. Monomers and oligomers may be used individually or in combination of two or more.

[0040] The monomer and / or oligomer may be used in any appropriate amount depending on the type of adhesive used. For example, preferably 100 parts by weight or less, and more preferably 5 to 50 parts by weight, per 100 parts by weight of the base polymer.

[0041] C-2. Photopolymerization Initiator Any suitable initiator can be used as the photopolymerization initiator. Examples of photopolymerization initiators include acylphosphine oxide photoinitiators such as ethyl 2,4,6-trimethylbenzylphenylphosphine and (2,4,6-trimethylbenzoyl)-phenylphosphine oxide; α-ketol compounds such as 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, and 1-hydroxycyclohexylphenylketone; and methoxyacetophenone. Acetophenone compounds such as 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, and 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinopropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether, and anisoin methyl ether; ketal compounds such as benzyldimethyl ketal; aromatic sulfonyl chloride compounds such as 2-naphthalenesulfonyl chloride; 1-phenone-1,1-propanedione-2-( Photoactive oxime compounds such as o-ethoxycarbonyl oxime; benzophenone compounds such as benzophenone, benzoylbenzoic acid, and 3,3'-dimethyl-4-methoxybenzophenone; thioxanthone compounds such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone; camphorquinone; halogenated ketones Examples include acylphosphonates and α-hydroxyacetophenones such as 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl-2-methylpropane-1. Preferably, 2,2-dimethoxy-2-phenylacetophenone and 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl-2-methylpropane-1 can be used. One photopolymerization initiator may be used alone, or two or more may be used in combination.

[0042] Commercially available photopolymerization initiators may be used. Examples include Omnirad 127 and Omnirad 651 from IGM Resins.

[0043] The photopolymerization initiator is used in any appropriate amount. The content of the photopolymerization initiator is preferably 0.5 to 20 parts by weight, and more preferably 0.5 to 10 parts by weight, per 100 parts by weight of the base polymer. If the content of the photopolymerization initiator is less than 0.5 parts by weight, it may not cure sufficiently when irradiated with ultraviolet light. If the content of the photopolymerization initiator exceeds 10 parts by weight, the storage stability of the adhesive may decrease.

[0044] C-3. Additives The adhesive may contain any suitable additives as needed. Examples of such additives include crosslinking agents, catalysts (e.g., platinum catalysts), tackifiers, plasticizers, pigments, dyes, fillers, antioxidants, conductive materials, UV absorbers, light stabilizers, release modifiers, softeners, surfactants, flame retardants, and solvents.

[0045] In one embodiment, the adhesive preferably further comprises a crosslinking agent. Examples of crosslinking agents include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, aziridine-based crosslinking agents, and chelate-based crosslinking agents. The content of the crosslinking agent is preferably 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, per 100 parts by weight of the base polymer contained in the UV-curable adhesive. If the content of the crosslinking agent is within the above range, the anchoring strength of the adhesive layer may be improved.

[0046] In one embodiment, an isocyanate-based crosslinking agent is preferably used. Isocyanate-based crosslinking agents are preferred because they can react with a variety of functional groups. Particularly preferred is a crosslinking agent having three or more isocyanate groups. By using an isocyanate-based crosslinking agent and setting the content of the crosslinking agent within the above range, it is possible to form an adhesive layer that exhibits excellent peelability and significantly reduces adhesive residue even after heating.

[0047] The thickness of the adhesive layer can be set to any appropriate value. Preferably, the thickness of the adhesive layer is 1 μm to 500 μm, more preferably 10 μm to 300 μm, and even more preferably 45 μm to 250 μm. By having the adhesive layer thickness within the above range, sufficient adhesion to the semiconductor wafer can be achieved.

[0048] D. Method for manufacturing adhesive tape The adhesive tape according to the embodiment of the present invention can be manufactured by any suitable method. For example, it can be obtained by applying an adhesive to a release liner, drying it to form an adhesive layer on the release liner, and then transferring the adhesive layer to a substrate. Alternatively, the adhesive tape can be obtained by applying an adhesive to a substrate and drying it. Various methods can be used to apply the adhesive, such as bar coating, air knife coating, gravure coating, gravure reverse coating, reverse roll coating, lip coating, die coating, dip coating, offset printing, flexographic printing, and screen printing. Any suitable drying method can be used.

[0049] E. Uses of adhesive tape The adhesive tape of the embodiment of the present invention can be suitably used in the manufacturing process of semiconductor wafers. As described above, the adhesive tape of the embodiment of the present invention can be suitably used in manufacturing methods that include contact with a processing liquid. Examples of semiconductor wafer manufacturing processes that use a processing liquid include a dicing process using a coolant liquid and a cleaning process using a cleaning liquid. By using the adhesive tape of the embodiment of the present invention, changes in adhesive strength can be suppressed even when in contact with a processing liquid. As a result, for example, when in contact with a coolant liquid in the dicing process, the occurrence of defects such as chip breakage in the dicing process can be suppressed. Also, when in contact with a cleaning liquid in the cleaning process, the detachment of the semiconductor wafer, which has been broken into small pieces by cleaning, from the adhesive tape can be suppressed. In one embodiment, the adhesive tape of the embodiment of the present invention can be suitably used as a dicing tape.

[0050] Any suitable processing solution can be used as the processing solution. For example, a processing solution containing an organic solvent such as ethylene glycol or propylene glycol, water, and any suitable rust inhibitor is recommended. Processing solutions containing these are preferred because they prevent wear of the dicing blades during blade dicing of semiconductor packages.

[0051] F. Selection method for adhesive tape The method for selecting an adhesive tape according to an embodiment of the present invention allows for the selection of an adhesive tape suitable for use in processes that include contact with a processing liquid. Adhesive tapes may come into contact with processing liquids such as coolant or cleaning liquids during the manufacturing process, and the adhesive strength of the adhesive layer may change due to contact with the processing liquid. Therefore, it is preferable to use an adhesive tape that has little effect on the adhesive strength depending on the processing liquid used. The method for selecting an adhesive tape according to an embodiment of the present invention includes measuring the Hansen solubility parameter of the processing liquid, measuring the Hansen solubility parameter of the adhesive used in the adhesive layer of the adhesive tape, calculating the relative energy difference from the Hansen solubility parameter of the processing liquid and the Hansen solubility parameter of the adhesive, and selecting an adhesive whose relative energy difference is an arbitrary value.

[0052] The Hansen solubility parameters of the processing solution and adhesive can be measured using the measurement method for the Hansen solubility parameters of the processing solution and adhesive described in Section A above. The obtained values ​​are used to calculate RED from equations (1) and (2). The suitability of the adhesive for the processing solution can be evaluated from the obtained RED value.

[0053] In one embodiment, it is preferable to select an adhesive in which the relative energy difference calculated from the Hansen solubility parameter of the processing solution and the Hansen solubility parameter of the adhesive is 0.9 or more. If the relative energy difference between the processing solution and the adhesive is 0.9 or more, appropriate adhesive strength can be maintained even when the adhesive tape and the adherend are subjected to a process in which they come into contact with the processing solution while bonded together. The relative energy difference of the adhesive to the processing solution is more preferably 1.0 or more, even more preferably 1.1 or more, and particularly preferably 1.2 or more.

[0054] As described above, in this specification, "processing liquid" refers to a liquid actually used in semiconductor wafer processing processes such as dicing (e.g., coolant). Ethylene glycol can be used, for example, as the main component of the coolant. In one embodiment, the processing liquid may be a liquid having a permanent dipole intermolecular force (δp) of 10 to 18, a dispersion force (δd) of 16 to 18, and a hydrogen bonding force (δh) of 13 to 26. In another embodiment, the processing liquid may be a liquid containing ethylene glycol and / or polyethylene glycol.

[0055] In one embodiment, the processing solution contains ethylene glycol. In this embodiment, an adhesive is selected in which the RED of the adhesive to the processing solution containing ethylene glycol is 0.9 or higher, preferably 1.2 or higher, and more preferably 1.6 or higher. This adhesive can be suitably used as an adhesive for adhesive tape used when performing dicing while in contact with a coolant liquid, which is a processing solution containing ethylene glycol. The numerical range of the evaluation criterion by RED may change depending on the application in which the adhesive tape is used. Furthermore, when the processing solution is ethylene glycol, the RED of the adhesive to the processing solution is preferably 1.6 or higher, more preferably 1.65 or higher, even more preferably 1.8 or higher, and particularly preferably 2.0 or higher. [Examples]

[0056] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the examples, unless otherwise specified, "parts" and "%" are based on weight.

[0057] [Example 1] A polymerization apparatus was used, consisting of a 1L round-bottom separable flask equipped with a separable cover, separatory funnel, thermometer, nitrogen inlet tube, Liebig condenser, vacuum seal, stirring rod, and stirring blade. 100 parts by weight of 2-ethylhexyl acrylate (2EHA), 25.5 parts by weight of acryloyl morpholine (ACMO), 9.5 parts by weight of hydroxyethyl acrylate (HEA), and 262.5 parts by weight of toluene were added to this apparatus, and the apparatus was purged with nitrogen. Next, 0.28 parts by weight of a polymerization initiator (manufactured by NOF Corporation, product name "Niper BW") was added to the apparatus. Subsequently, 9 parts by weight of HEA were added dropwise to the apparatus, and polymerization was carried out. The reaction temperature was 60°C, and the reaction was carried out for 8 hours. Next, 0.063 parts by weight of dibutyltin dilaurate and 12.25 parts by weight of a radiation-polymerizable carbon-carbon double bond compound (manufactured by Showa Denko, trade name "Kalenz MOI") were added to the polymerization apparatus, and addition polymerization was carried out at 50°C for 14 hours to obtain polymer A (base polymer) with a weight-average molecular weight of 680,000, in which double bonds were introduced into the side chains. 100 parts by weight of the obtained polymer A, 30 parts by weight of ultraviolet curing resin (manufactured by Mitsubishi Chemical Corporation, product name "Shiko (registered trademark) UV-1700TL"), 0.2 parts by weight of crosslinking agent (manufactured by Mitsui Chemicals Corporation, product name "Takenate D-101A"), and 3 parts by weight of photopolymerization initiator (manufactured by IGM Resins, product name "Omnirad 651") were mixed, and toluene was added as appropriate to obtain an adhesive with a solid content of 20% by weight. The obtained adhesive was applied to the release surface of a release liner (Mitsubishi Chemical Corporation, product name "Diafoil MRF#38") and dried in a drying oven at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm on the release liner. Next, a substrate (Gunze Corporation, product name "Funcrea KKZ#150", polyolefin resin film, thickness 150 μm) was laminated onto the side of the adhesive layer that was not bonded to the release liner and bonded with a hand roller. Then, the material was heated in a 50°C oven for 48 hours to perform aging and obtain an adhesive tape.

[0058] [Example 2] Polymer B (base polymer) with a weight-average molecular weight of 680,000 was obtained in the same manner as in Example 1, except that the amount of radiation-polymerizable carbon-carbon double bond compound (manufactured by Showa Denko, trade name "Kalenz MOI") added was 22.5 parts by weight. An adhesive was obtained in the same manner as in Example 1, except that polymer B was used instead of polymer A. An adhesive tape was obtained using the obtained adhesive in the same manner as in Example 1.

[0059] [Example 3] A polymerization apparatus was used, consisting of a 1 L round-bottom separable flask equipped with a separable cover, separatory funnel, thermometer, nitrogen inlet tube, Liebig condenser, vacuum seal, stirring rod, and stirring blade. 90.71 parts by weight of lauryl methacrylate (LMA), 4 parts by weight of hydroxyethyl methacrylate (HEMA), and 177.23 parts by weight of toluene were added to this polymerization apparatus, and the apparatus was purged with nitrogen. Next, 0.2 parts by weight of a polymerization initiator (azobisisobutyronitrile (AIBN)) was added to the apparatus. Subsequently, 5.8 parts by weight of HEMA were added dropwise to the apparatus, and polymerization was carried out. The reaction temperature was 60°C for 7 hours, followed by aging at 79°C for 5 hours. Next, 0.063 parts by weight of dibutyltin dilaurate and 9.07 parts by weight of a radiation-polymerizable carbon-carbon double bond compound (manufactured by Showa Denko, trade name "Kalenz MOI") were added to the polymerization apparatus, and addition polymerization was carried out at 50°C for 6 hours to obtain polymer C (base polymer) with a weight-average molecular weight of 1 million, in which double bonds were introduced into the side chains. An adhesive was prepared in the same manner as in Example 1, except that polymer C was used. An adhesive tape was obtained using the obtained adhesive in the same manner as in Example 1.

[0060] [Example 4] A polymerization apparatus was used, consisting of a 1L round-bottom separable flask equipped with a separable cover, separatory funnel, thermometer, nitrogen inlet tube, Liebig condenser, vacuum seal, stirring rod, and stirring blade. 50 parts by weight of butyl acrylate (BA), 39 parts by weight of ethyl acrylate (EA), 10 parts by weight of HEA, and 507.03 parts by weight of toluene were added to this polymerization apparatus, and the apparatus was purged with nitrogen. Next, 0.28 parts by weight of a polymerization initiator (manufactured by NOF Corporation, product name "Niper BW") was added to the apparatus. Subsequently, 10 parts by weight of HEA was added dropwise to the apparatus, and polymerization was carried out. The reaction temperature was 61°C for 6 hours, followed by aging at 78°C for 1 hour. Next, 0.063 parts by weight of dibutyltin dilaurate and 21.3 parts by weight of a radiation-polymerizable carbon-carbon double bond compound (manufactured by Showa Denko, trade name "Kalenz MOI") were added to the polymerization apparatus, and addition polymerization was carried out at 50°C for 10 hours to obtain polymer D (base polymer) with a weight-average molecular weight of 500,000 in which double bonds were introduced into the side chains. An adhesive tape was obtained in the same manner as in Example 1, except that the obtained polymer D was used.

[0061] [Example 5] A polymerization apparatus was used, consisting of a 1L round-bottom separable flask equipped with a separable cover, separatory funnel, thermometer, nitrogen inlet tube, Liebig condenser, vacuum seal, stirring rod, and stirring blade. 88.8 parts by weight of 2-EHA, 6 parts by weight of HEA, and 148.9 parts by weight of toluene were added to this polymerization apparatus, and the apparatus was purged with nitrogen. Next, 0.28 parts by weight of a polymerization initiator (manufactured by NOF Corporation, product name "Niper BW") was added to the apparatus. Subsequently, 5 parts by weight of HEA were added dropwise to the apparatus, and polymerization was carried out. The reaction temperature was 59.5°C for 6 hours, followed by aging at 78°C for 2 hours. Next, 0.22 parts by weight of dibutyltin dilaurate and 12 parts by weight of a radiation-polymerizable carbon-carbon double bond compound (manufactured by Showa Denko, trade name "Kalenz MOI") were added to the polymerization apparatus, and addition polymerization was carried out at 50°C for 8 hours to obtain polymer E (base polymer) with a weight-average molecular weight of 450,000 in which double bonds were introduced into the side chains. An adhesive tape was obtained in the same manner as in Example 1, except that the obtained polymer E was used.

[0062] (Comparative Example 1) A polymerization apparatus was used, consisting of a 1L round-bottom separable flask equipped with a separable cover, separatory funnel, thermometer, nitrogen inlet tube, Liebig condenser, vacuum seal, stirring rod, and stirring blade. 30 parts by weight of 2-EHA, 70 parts by weight of methyl acrylate (MA), 10 parts by weight of acrylic acid (AA), 0.4 parts by weight of polymerization initiator (manufactured by NOF Corporation, product name "Niper BW"), and 507.03 parts by weight of ethyl acetate were added to this polymerization apparatus, and the apparatus was purged with nitrogen. The reaction was then carried out at a reaction temperature of 62°C for 7 hours, followed by aging at 80°C for 2 hours to obtain polymer F with a weight-average molecular weight of 500,000. 100 parts by weight of the obtained polymer F, 50 parts by weight of UV-curing resin 1 (manufactured by Mitsubishi Chemical Corporation, product name "Shiko (registered trademark) UV-1700TL"), 45 parts by weight of UV-curing resin 2 (manufactured by Mitsubishi Chemical Corporation, product name "Shiko (registered trademark) UV-3000TL"), 5 parts by weight of crosslinking agent (manufactured by Mitsui Chemicals Corporation, product name "Takenate D-101A"), and 3 parts by weight of photopolymerization initiator (manufactured by IGM Resins, product name "Omnirad 651") were mixed, and toluene was added as appropriate to obtain an adhesive with a solid content of 20% by weight. An adhesive tape was obtained in the same manner as in Example 1, except that this adhesive was used.

[0063] (Comparative Example 2) A polymerization apparatus was used, consisting of a 1 L round-bottom separable flask equipped with a separable cover, separatory funnel, thermometer, nitrogen inlet tube, Liebig condenser, vacuum seal, stirring rod, and stirring blade. To this polymerization apparatus, 100 parts by weight of 2-methoxyethyl acrylate (2-MEA), 27.1 parts by weight of ACMO, 22.3 parts by weight of HEA, 23.9 parts by weight of a radiation-polymerizable carbon-carbon double bond compound (Showa Denko Corporation, trade name "Karens MOI"), 0.3 parts by weight of a polymerization initiator (Nofus Co., Ltd., product name "Niper BW"), and 520.44 parts by weight of ethyl acetate were added, and the apparatus was purged with nitrogen. The reaction was then carried out at a reaction temperature of 50°C for 12 hours to obtain polymer G with a weight-average molecular weight of 900,000. An adhesive tape was obtained in the same manner as in Example 1, except that the obtained polymer G was used.

[0064] <Rating> The following evaluations were performed using the adhesive tapes used in the examples and comparative examples. The results are shown in Table 3. 1. Relative energy difference based on the Hansen solubility parameter of adhesives in ethylene glycol. In a resealable container, the adhesive (solid content) obtained in the examples or comparative examples was added to one of the solvents listed in Table 2 at a concentration of 0.8 parts by weight / 10 mL. The container was then handshaken to thoroughly mix the adhesive and solvent. The container was then left to stand for 24 hours at room temperature (23°C). Afterward, the container was visually inspected. The presence of precipitate or aggregates in the container indicated insolubility, while the absence of precipitate and aggregates indicated solubility. This test was performed for 20 solvents listed in Table 2. From the obtained test results, a sphere (Hansen sphere) was plotted in Hansen space, containing the coordinates of the solvent in which the target substance was dissolved, but excluding the coordinates of the solvent in which the target substance was not dissolved. HSP values ​​were calculated using the Hansen solubility parameter calculation software HSPiP (HSPiP 5th Edition Ver. 5.3.03, Hansen-Solublity.com). The dispersion force (δd) of ethylene glycol registered in the software was then calculated. s ), permanent dipole intermolecular force (δp s ), and hydrogen bonding force (δh s ) and the dispersion force of the adhesive obtained from software calculations (δd ad ), permanent dipole intermolecular force (δp ad ), and hydrogen bonding force (δh ad The coordinate distance Ra between ethylene glycol and the adhesive was calculated from the following formula (1). Ra=[4×(δd s -δd ad ) 2 +(δp s -δp ad ) 2 +(δh s -δh ad ) 2 ] 1 / 2 (1) Next, the coordinate distance Ra between the obtained ethylene glycol and the adhesive, and the radius R of the Hansen sphere of the adhesive are determined. ad The relative energy difference (RED) of the adhesive in relation to ethylene glycol was calculated using the following formula (2): (δd ad ), permanent dipole intermolecular force (δpad ), and hydrogen bonding force (δh ad ), and the radius R of the Hansen sphere of the adhesive. ad This is shown in Table 3. RED = Ra / R ad (2) [Table 2]

[0065] 2. Anchoring capacity and rate of reduction in anchoring capacity Two samples were taken from the adhesive tape obtained in the examples or comparative examples, cut to a width of 20 mm and a length of 150 mm. The adhesive tape used was stored in a room at 25°C for at least 2 hours. The release liner was peeled off one of the samples, and then the adhesive layer of a commercially available adhesive tape (Nitto Denko Corporation, product name "BT-315") was bonded to the adhesive layer side of the sample, and left to stand at 25°C for 30 minutes. After that, a T-type peel test was performed using a tensile testing machine (Shimadzu Corporation, product name "AG-50kNXplus") at a peeling speed of 300 mm / min, and the anchoring force (N / 20 mm) was measured. The other sample was subjected to ethylene glycol (dispersion force (δd s )17.0, permanent dipole intermolecular force (δp s )11.1, hydrogen bonding force (δh s The sample was immersed in ethylene glycol (26.2) at room temperature for 10 minutes. Then, the sample was removed from the ethylene glycol and immersed in pure water at room temperature for 10 minutes. Next, the sample was air-dried at room temperature for 24 hours. Then, the adhesive layer of a commercially available adhesive tape (Nitto Denko Corporation, product name "BT-315", adhesive strength 15.0 N / 20 mm) was attached to the adhesive layer side of the sample and left to stand at 25°C for 30 minutes. After that, a T-type peel test was performed using a tensile testing machine (Shimadzu Corporation, product name "AG-50kNXplus") at a peeling speed of 300 mm / min, and the anchoring force (N / 20 mm) was measured. The rate of decrease was calculated from the anchoring force of the sample not immersed in ethylene glycol and the anchoring force of the sample immersed in ethylene glycol using the following formula. Anchoring force reduction rate (%) = {(Anchoring force of sample not immersed in ethylene glycol (N / 20mm)) - (Anchoring force of sample immersed in ethylene glycol (N / 20mm))} / (Anchoring force of sample not immersed in ethylene glycol (N / 20mm)) × 100

[0066] 3. Adhesive strength The adhesive tape obtained in the examples or comparative examples was cut to a width of 20 mm and a length of 150 mm to prepare a sample. The cutting was performed so that the MD direction of the adhesive tape was in the length direction. The cut adhesive tape was bonded to a silicon wafer (manufactured by Shin-Etsu Chemical Co., Ltd., product name "Silicon Wafer"), and the adhesive tape was pressed down by moving a 2 kg hand roller back and forth once in an atmosphere of 23°C, and left to stand for 30 minutes. After that, a 180° peel test was performed at 23°C, 50% RH atmosphere, and a peeling speed of 50 mm / min to determine the force required to peel off the adhesive tape, and the adhesive strength was measured using a tensile testing machine (manufactured by Shimadzu Corporation, product name "AG-50kNXplus"). Similarly, adhesive tape was cut to a width of 20 mm and a length of 150 mm, bonded to a silicon wafer, and pressed down with a 2 kg hand roller in a 23°C atmosphere for one back-and-forth motion. The wafer was then left to stand for 30 minutes. Next, ultraviolet (UV) light was applied to an integrated light intensity of 460 mJ / cm². 2 Ultraviolet light was irradiated from the adhesive layer side using a UV irradiation device for dicing processes (manufactured by Nitto Denko Corporation, product name "UM810") to achieve a 365nm equivalent. Subsequently, a 90° peel test was performed at 23°C, 50% RH atmosphere, and a peeling speed of 300 mm / min to measure the force required to peel the adhesive tape, and the adhesive strength was measured using a tensile testing machine (manufactured by Shimadzu Corporation, product name "AG-50kNXplus").

[0067] 4. Adhesion after heating The adhesive tape obtained in the examples or comparative examples was cut to a width of 20 mm and a length of 150 mm to prepare a sample. The cutting was performed so that the MD direction of the adhesive tape was in the length direction. The cut adhesive tape was bonded to a silicon wafer (manufactured by Shin-Etsu Chemical Co., Ltd., product name "Silicon Wafer"), and the adhesive tape was pressed down by moving a 2 kg hand roller back and forth once in an atmosphere of 23°C, and left to stand for 30 minutes. Next, the adhesive tape was placed in an oven and heated at 75°C for 3 minutes, and then the adhesive tape was removed from the oven and left to stand at room temperature for 30 minutes. After that, a 180° peel test was performed at 23°C, 50% RH atmosphere, and a peeling speed of 50 mm / min to measure the force required to peel off the adhesive tape, and the adhesive strength was measured using a tensile testing machine (manufactured by Shimadzu Corporation, product name "AG-50kNXplus"). Similarly, adhesive tape was cut to a width of 20 mm and a length of 150 mm, bonded to a silicon wafer, and pressed down with a 2 kg hand roller in a 23°C atmosphere for one pass, then left to stand for 30 minutes. Next, the adhesive tape was placed in an oven and heated at 75°C for 3 minutes, and then the adhesive tape was removed from the oven and left to stand at room temperature for 30 minutes. Then, ultraviolet (UV) light was applied with an integrated intensity of 460 mJ / cm². 2 The dicing process UV irradiation device (manufactured by Nitto Denko Corporation, product name "UM810") was irradiated from the adhesive layer side to achieve a 365nm equivalent. Subsequently, a 90° peel test was performed at 23°C, 50% RH atmosphere, and a peeling speed of 300 mm / min to measure the force required to peel the adhesive tape. The adhesive strength was then measured using a tensile testing machine (manufactured by Shimadzu Corporation, product name "AG-50kNXplus").

[0068] [Table 3]

[0069] The adhesive tape of the embodiment of the present invention exhibited suppressed reduction in anchoring force even when in contact with the processing liquid. Furthermore, it provided sufficient adhesive strength before UV irradiation and could be easily peeled off the adherend after UV irradiation. [Industrial applicability]

[0070] The adhesive tape according to the embodiment of the present invention can be suitably used for semiconductor wafer processing applications. [Explanation of Symbols]

[0071] 10 Adhesive layer 20 Base material 100 Adhesive Tapes

Claims

1. It comprises a base material and an adhesive layer composed of an adhesive, An adhesive tape used in a manufacturing method that includes contact with a processing liquid, An adhesive tape wherein the relative energy difference of the adhesive with respect to ethylene glycol, based on the Hansen solubility parameter, is 1.6 or greater.

2. The adhesive tape according to claim 1, wherein the adhesive strength of the adhesive layer before ultraviolet irradiation is 3.5 N / 20 mm or more.

3. The adhesive tape according to claim 1, wherein the rate of reduction in anchoring force determined by ethylene glycol contact evaluation is less than 4%.

4. The adhesive tape according to claim 1, wherein the adhesive comprises a base polymer, and the content of a monomer component having a polar group in the monomer composition used for polymerization of the base polymer is 50% by weight or less.

5. The aforementioned adhesive is an ultraviolet-curing adhesive, The adhesive tape according to claim 4, wherein the base polymer is a polymer having a polymerizable carbon-carbon double bond.

6. The adhesive tape according to claim 5, wherein the adhesive contains 0.1 parts by weight or more of a crosslinking agent per 100 parts by weight of a base polymer.

7. The adhesive tape according to claim 1, wherein the adhesive strength before ultraviolet irradiation is 5 N / 20 mm or more.

8. The adhesive tape according to claim 5, wherein the adhesive strength after ultraviolet irradiation is 0.5 N / 20 mm or less.

9. An adhesive tape according to any one of claims 1 to 8, used for semiconductor processing.

10. To measure the Hansen solubility parameter of the processing solution used in the semiconductor wafer processing process, To measure the Hansen solubility parameter of the adhesive used in the adhesive layer of adhesive tape, The relative energy difference is calculated from the Hansen solubility parameter of the processing liquid and the Hansen solubility parameter of the adhesive. A method for selecting an adhesive tape, comprising selecting an adhesive whose relative energy difference is an arbitrary value.

11. A method for selecting an adhesive tape according to claim 10, wherein an adhesive having a relative energy difference of 0.9 or more is selected.

12. The method for selecting an adhesive tape according to claim 10, wherein the processing liquid is ethylene glycol and an adhesive is selected in which the relative energy difference is 1.6 or more.

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