Adhesive tape

Abstract

The purpose of the present invention is to provide a pressure-sensitive adhesive tape that can have chip components preferably pasted thereto when receiving the chip components, that exhibits excellent detachment performance when re-transferring the chip components, and that can prevent an adhesive from being left on the chip components. A pressure-sensitive adhesive tape according to the present invention has at least one layer of a base material and at least one layer of a pressure sensitive adhesive layer. The pressure sensitive adhesive layer has a shear storage modulus G' of 1 MPa or less at a frequency of 10 Hz at -20°C. The pressure-sensitive adhesive tape exhibits a surface detachment strength of 0.5 MPa or less with respect to SUS in an attachment area of 10 mm × 10 mm.

Description

Technical Field

[0001] The present invention relates to an adhesive tape.

Background Art

[0002] In the manufacturing process of semiconductor devices, it is sometimes necessary to transfer a large number of chip components arranged on an adhesive layer onto a drive circuit board. For example, a micro LED display is a display device in which each chip constituting a pixel is a fine light emitting diode (LED) chip, and this micro LED chip emits light spontaneously to display an image. The micro LED display has high contrast, fast response speed, and can be made thin because it does not require a color filter used in liquid crystal displays, organic EL displays, etc. Therefore, it is attracting attention as a next-generation display device. In a micro LED display, a large number of micro LED chips are densely arranged in a planar manner.

[0003] In the manufacturing process of semiconductor devices such as a micro LED display, for example, a transfer laminate in which a large number of chip components are arranged on an adhesive layer is opposed to a drive circuit board, and the chip components are peeled off from the transfer laminate to make an electrical connection with the drive circuit board (transfer process).

[0004] The transfer process may be performed multiple times. That is, before finally transferring the chip components onto the drive circuit board, the chip components are once transferred onto a carrier material for transportation or processing, and then the chip components are re-transferred from the carrier material onto another carrier material or the drive circuit board. As the carrier material, for example, Patent Document 1 describes a transfer substrate including at least a base material and an impact absorption layer.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] International Publication No. 2019 / 065441 [Overview of the project] [Problems that the invention aims to solve]

[0006] Since the carrier material also needs to have the ability to temporarily hold chip components, the use of adhesive tape with an adhesive layer is also being considered. However, when conventional adhesive tape was used as a carrier material, the chip components sometimes failed to adhere to the adhesive tape when being received, resulting in poor transfer. Furthermore, when re-transferring the chip components to another carrier material or drive circuit board after receiving them, problems arose such as poor detachment of the chip components or, even if the chip components could be detached, adhesive residue from the adhesive layer adhering to the chip components.

[0007] The present invention aims to provide an adhesive tape that can securely attach chip components when receiving them, exhibits excellent peeling performance when re-transferring chip components, and minimizes adhesive residue on the chip components. [Means for solving the problem]

[0008] Disclosure 1 is an adhesive tape having at least one substrate layer and at least one adhesive layer, wherein the adhesive layer has a shear storage modulus G' of 1 MPa or less at a frequency of 10 Hz and -20°C, and the adhesive tape has a surface peel strength of 0.5 MPa or less on SUS over an application area of ​​10 mm × 10 mm. Disclosure 2 is an adhesive tape according to Disclosure 1, wherein the adhesive layer has a shear storage modulus G' of 0.3 MPa or less at a frequency of 10 Hz and -20°C. Disclosure 3 is an adhesive tape according to Disclosure 1 or 2, wherein the adhesive layer has a shear storage modulus G' of 0.04 MPa or less at a frequency of 10 Hz and 23°C. Disclosure 4 is an adhesive tape according to Disclosure 1, 2, or 3, wherein the adhesive layer has a thickness of 40 μm or more. Disclosure 5 is an adhesive tape according to Disclosure 1, 2, 3, or 4, wherein the surface peel strength to SUS over an application area of ​​10 mm x 10 mm is 0.01 MPa or more. Disclosure 6 is an adhesive tape according to Disclosure 1, 2, 3, 4, or 5, wherein the surface peel strength to SUS over an application area of ​​10 mm x 10 mm is 0.2 MPa or less. Disclosure 7 is an adhesive tape according to Disclosure 1, 2, 3, 4, 5, or 6, wherein the adhesive layer is an acrylic adhesive layer containing a (meth)acrylic polymer. Disclosure 8 is the adhesive tape of Disclosure 7, wherein the (meth)acrylic polymer has a hydroxyl value of 45 mgKOH / g or less. Disclosure 9 is an adhesive tape according to Disclosure 7 or 8, wherein the (meth)acrylic polymer contains 80% by weight or more of constituent units derived from (meth)acrylic acid ester (a), which has a glass transition temperature (Tg) of 0°C or less when it is a homopolymer. Disclosure 10 is an adhesive tape according to Disclosure 9, wherein the (meth)acrylic polymer contains 40% by weight or more of constituent units derived from a (meth)acrylic acid ester (a-1) having an alkyl group with 12 or more carbon atoms and having a glass transition temperature (Tg) of 0°C or less when it is a homopolymer. Disclosure 11 is an adhesive tape according to Disclosure 10, wherein the (meth)acrylic acid ester (a-1) having an alkyl group with 12 or more carbon atoms and having a glass transition temperature (Tg) of 0°C or less when it is a homopolymer contains lauryl (meth)acrylate. Disclosure 12 is an adhesive tape according to Disclosure 9, wherein the (meth)acrylic polymer contains 90% by weight or more of constituent units derived from a (meth)acrylic acid ester (a) whose glass transition temperature (Tg) when it is the homopolymer is 0°C or lower. Disclosure 13 is an adhesive tape according to Disclosure 7, 8, 9, 10, 11, or 12, wherein the (meth)acrylic polymer contains a structure derived from a hydroxyl group-containing monomer. Disclosure 14 is an adhesive tape according to Disclosures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, or 13, wherein the adhesive layer is a photocurable adhesive layer. Disclosure 15 is an adhesive tape of Disclosure 7, 8, 9, 10, 11, 12, or 13, wherein the (meth)acrylic polymer contains carbon-carbon double bonds in its side chains. Disclosure 16 is an adhesive tape according to Disclosure 15, wherein the (meth)acrylic polymer has a carbon-carbon double bond equivalent of 0.5 meq / g or less. Disclosure 17 is an adhesive tape of Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 used to receive a part in a part transfer process. Disclosure 18 is an adhesive tape of Disclosure 17, wherein the component is a semiconductor device. The present invention will be described in detail below.

[0009] The inventors have discovered that in an adhesive tape having at least one substrate layer and at least one adhesive layer, by adjusting both the low-temperature shear storage modulus G' of the adhesive layer and the surface peel strength measured by a specific method to be below a certain value, an adhesive tape useful as a carrier material can be obtained. Specifically, the inventors have discovered that such an adhesive tape can securely attach chip components when receiving them, exhibit excellent peeling performance when re-transferring chip components, and suppress adhesive residue on the chip components, thus completing the present invention.

[0010] Figure 1 shows a schematic cross-sectional view illustrating an example of the process of transferring chip components placed on an adhesive layer onto an adhesive tape. In the process shown in Figure 1, a chip component 1 is placed on an adhesive layer 4 laminated on a substrate 5, and the chip component 1 is peeled off the adhesive layer 4 by a method such as irradiating it with laser light. The adhesive tape 8 is a carrier material that receives the chip component 1 peeled off from the adhesive layer 4 and then retransfers the chip component 1 onto another carrier material or drive circuit board. The adhesive tape 8 has a substrate 3 and an adhesive layer 2. The laminate 9 of the base material 5 and the adhesive layer 4 may, for example, be a single-sided adhesive tape in which the base material 5 is a base material such as a resin film and the adhesive layer 4 consists only of an adhesive layer, or it may be a laminate of a support and a double-sided adhesive tape in which the base material 5 is a support such as a glass substrate and the adhesive layer 4 is a double-sided adhesive tape (which may have a base material).

[0011] The adhesive tape of the present invention is an adhesive tape having at least one base material and at least one adhesive layer. Having the above-mentioned base material, the adhesive tape of the present invention has appropriate stiffness and excellent handling properties, making it a useful adhesive tape as a carrier material capable of receiving and re-transferring chip components.

[0012] The above-mentioned substrate is not particularly limited, and examples of materials for the substrate include polyethylene terephthalate, polyethylene naphthalate, polyacetal, polyamide, polycarbonate, polyphenylene ether, polybutylene terephthalate, ultra-high molecular weight polyethylene, syndiotactic polystyrene, polyarylate, polysulfone, polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyimide, polyetherimide, fluororesin, liquid crystal polymer, etc. Among these, polyethylene terephthalate and polyethylene naphthalate are preferred due to their excellent heat resistance.

[0013] The thickness of the above-mentioned substrate is not particularly limited, but a preferred lower limit is 4 μm and a preferred upper limit is 188 μm. By having the thickness of the above-mentioned substrate within the above range, an adhesive tape can be made that has appropriate stiffness and excellent handling properties. A more preferred lower limit for the thickness of the above-mentioned substrate is 50 μm, a more preferred upper limit is 125 μm, an even more preferred lower limit is 75 μm, and an even more preferred upper limit is 100 μm.

[0014] The above adhesive layer has an upper limit of 1 MPa for its shear storage modulus G' at a frequency of 10 Hz and a temperature of -20°C. The reception of chip components by an adhesive tape is usually performed at high speed. Based on the temperature - speed conversion rule, the shear storage modulus G' under such high - speed force application has a high correlation with the shear storage modulus G' at low temperatures. Therefore, the inventors examined the shear storage modulus G' of the above - mentioned adhesive layer at low temperatures. If the shear storage modulus G' at a frequency of 10 Hz and - 20°C is 1 MPa or less, the cushioning property when the adhesive layer receives the chip component is improved, and the adhesive tape can make the chip component stick well when receiving the chip component. The preferable upper limit of the shear storage modulus G' at a frequency of 10 Hz and - 20°C is 0.8 MPa, a more preferable upper limit is 0.5 MPa, and a still more preferable upper limit is 0.3 MPa. The lower limit of the shear storage modulus G' at a frequency of 10 Hz and - 20°C is not particularly limited. From the perspective of further improving the peeling performance when re - transferring the chip component, the preferable lower limit is 0.05 MPa, and a more preferable lower limit is 0.1 MPa.

[0015] The shear storage modulus G' of the above - mentioned adhesive layer at room temperature is not particularly limited. However, the preferable upper limit of the shear storage modulus G' at a frequency of 10 Hz and 23°C is 0.1 MPa. If the shear storage modulus G' at a frequency of 10 Hz and 23°C is 0.1 MPa or less, the adhesive tape can make the chip component stick better when receiving the chip component. A more preferable upper limit of the shear storage modulus G' at a frequency of 10 Hz and 23°C is 0.04 MPa. The lower limit of the shear storage modulus G' at a frequency of 10 Hz and 23°C is not particularly limited. From the perspective of further improving the peeling performance when re - transferring the chip component, the preferable lower limit is 0.01 MPa, and a more preferable lower limit is 0.015 MPa.

[0016] The shear storage modulus G' of the adhesive layer at -20°C and 23°C at a frequency of 10 Hz can be obtained, for example, as the storage modulus at each temperature when measuring the dynamic viscoelastic spectrum from -40 to 140°C under the conditions of a heating rate of 5°C / min in the simple temperature increase mode and 10 Hz using a viscoelastic spectrometer (manufactured by IT Measurement and Control Co., Ltd., DVA-200), etc. When the adhesive layer is a curable adhesive layer, the shear storage modulus G' of the adhesive layer means the shear storage modulus G' measured for the adhesive layer before curing. When the thickness of the above adhesive layer is less than 100 μm, the adhesive layer for measurement is formed so that the thickness becomes 100 μm or more by overlapping the above adhesive layers. The shear storage modulus G' is measured for the obtained adhesive layer for measurement as described above.

[0017] The upper limit of the peel strength of the above adhesive tape with respect to SUS at a sticking area of 10 mm × 10 mm is 0.5 MPa. If the above peel strength is 0.5 MPa or less, the adhesive force of the above adhesive tape does not become too high, so that excellent peel performance can be exhibited when retransferring the chip component, and the remaining glue on the chip component can be suppressed. The preferable upper limit of the above peel strength is 0.4 MPa, and the more preferable upper limit is 0.2 MPa. The lower limit of the above peel strength is not particularly limited, but from the viewpoint of further improving the holding performance of the chip component, the preferable lower limit is 0.005 MPa, and the more preferable lower limit is 0.0 (1) MPa.

[0018] Fig. 2 shows a diagram schematically showing a method for measuring the peel strength of the adhesive tape. First, cut the adhesive tape 8 to 10mm x 10mm. Attach the adhesive layer of the cut adhesive tape 8 to the SUS jig 12 (SUS304) and press it down at 0.3 MPa for 10 seconds. Attach one side of the measuring double-sided adhesive tape 11 (manufactured by Sekisui Chemical Co., Ltd., product name #560, or equivalent) to the back of the adhesive tape 8 attached to the SUS jig 12. Attach the other side of the measuring double-sided adhesive tape 11 to the 5mm thick glass plate 10. Then, if the adhesive layer of the adhesive tape 8 is a curing type adhesive layer, for example, use a UV lamp with a wavelength of 365nm to apply a UV light at an intensity of 10mW / cm². 2 , irradiation amount 2500mJ / cm 2 The adhesive layer is hardened by irradiating the glass plate 10 with ultraviolet light under the specified conditions. That is, if the adhesive layer is a hardening type adhesive layer, the surface peel strength of the adhesive tape refers to the surface peel strength measured for the adhesive tape after the adhesive layer has hardened. After that, the glass plate 10 is fixed to a tensile testing machine (Shimadzu Corporation, AGS-X, or equivalent). Under conditions of room temperature 23°C and relative humidity 50%, a tensile test is performed using a tensile testing machine (Shimadzu Corporation, AGS-X, or equivalent) to pull the SUS jig 12 vertically (in the direction of the arrow in the figure) at a peel speed of 200 mm / min, and the surface peel strength is measured. Note that the surface peel strength refers to the maximum peel strength. If the adhesive tape is a double-sided adhesive tape, the surface peel strength is measured using a tensile testing machine in the same manner, except that the adhesive layer on the side opposite to the side to be measured is attached and fixed to the glass plate. In this case, the adhesive layer on the side opposite to the side to be measured of the adhesive tape may be attached and fixed directly to the glass plate, or it may be fixed via the measuring double-sided adhesive tape 11.

[0019] The thickness of the adhesive layer described above is not particularly limited, but a preferred lower limit is 30 μm and a preferred upper limit is 200 μm. If the thickness is within the above range, the cushioning effect of the adhesive layer when receiving the chip component is further improved, and the adhesive tape can better adhere the chip component when receiving it. A more preferred lower limit for the thickness is 40 μm, a more preferred upper limit is 150 μm, an even more preferred lower limit is 70 μm, and an even more preferred upper limit is 100 μm.

[0020] The method for adjusting the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape to the above range is not particularly limited. Examples include adjusting the composition, molecular weight (weight-average molecular weight (Mw)), hydroxyl value, double bond equivalent, etc., of the base polymer contained in the adhesive layer, and adjusting the degree of crosslinking (gel fraction) of the adhesive layer.

[0021] The adhesive layer described above is not particularly limited and includes, for example, an acrylic adhesive layer, a rubber-based adhesive layer, a urethane adhesive layer, a silicone-based adhesive layer, and the like. Among these, an acrylic adhesive layer containing a (meth)acrylic polymer is preferred because it is easy to adjust the molecular weight and degree of crosslinking, and it is excellent in terms of heat resistance, weather resistance, and cost.

[0022] The above-mentioned (meth)acrylic polymer is a polymer that contains constituent units derived from (meth)acrylic monomers. The above (meth)acrylic monomers are not particularly limited, and examples include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, isobutyl (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, lauryl (meth)acrylate, isomiristyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, etc. These (meth)acrylic monomers may be used alone or in combination of two or more.

[0023] In particular, (meth)acrylic acid ester (a) (hereinafter also simply referred to as "(meth)acrylic acid ester (a)") which has a glass transition temperature (Tg) of 0°C or less when used as a homopolymer is preferred. That is, it is preferable that the (meth)acrylic polymer contains constituent units derived from the (meth)acrylic acid ester (a). The inclusion of such relatively flexible structural units in the (meth)acrylic polymer makes it easier to adjust the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape to the above range. As a result, the adhesive tape has improved peel performance when re-transferring chip components and allows for better adhesion of chip components when receiving them. In particular, the inclusion of such relatively flexible structural units in the (meth)acrylic polymer and the adjustment of the degree of crosslinking (gel fraction) of the adhesive layer to an appropriate range makes it easier to adjust the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape to a more favorable range.

[0024] The glass transition temperature (Tg) of the above (meth)acrylic acid ester (a) is not particularly limited as long as it is 0°C or lower, but a preferred lower limit is -80°C and a preferred upper limit is -5°C, as this further improves the peeling performance when re-transferring chip components and allows for better adhesion of chip components when receiving them. A more preferred lower limit for the above glass transition temperature (Tg) is -70°C and a more preferred upper limit is -10°C. Furthermore, the glass transition temperature (Tg) of homopolymers can be measured for homopolymers with a weight-average molecular weight (Mw) of approximately 5,000 to 1,000,000 or a degree of polymerization of approximately 500,000 to 10,000, for example, using differential scanning calorimetry (manufactured by T.A. Instruments).

[0025] The above (meth)acrylic acid ester (a) preferably contains (meth)acrylic acid ester (a-1) (hereinafter also simply referred to as "(meth)acrylic acid ester (a-1)") which has an alkyl group having 12 or more carbon atoms and a glass transition temperature (Tg) of 0°C or less when it is a homopolymer. It is also preferable that the above (meth)acrylic acid ester (a) contains (meth)acrylic acid ester (a-2) (hereinafter also simply referred to as "(meth)acrylic acid ester (a-2)") which has an alkyl group having 7 or more carbon atoms and less than 12 carbon atoms and a glass transition temperature (Tg) of 0°C or less when it is a homopolymer. The inclusion of these relatively long-carbon alkyl groups in the (meth)acrylic polymer makes it easier to adjust the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape to a more favorable range. In particular, it is more preferable that the (meth)acrylic acid ester (a) contains both the (meth)acrylic acid ester (a-1) and the (meth)acrylic acid ester (a-2), as this makes it easier to adjust the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape to a more favorable range.

[0026] The above (meth)acrylic acid ester (a-1) is not particularly limited, and among the (meth)acrylic monomers mentioned above, examples include lauryl acrylate (Tg of -23°C when homopolymerized) and lauryl methacrylate (Tg of -65°C when homopolymerized). Furthermore, examples include isomiristyl acrylate (Tg of -56°C when homopolymerized) and isostearyl acrylate (Tg of -18°C when homopolymerized). Among these, at least one selected from the group consisting of lauryl acrylate, lauryl methacrylate, and isostearyl acrylate is preferred because it makes it easier to adjust the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape to a more preferred range. Furthermore, lauryl (meth)acrylate is more preferred, and lauryl acrylate is even more preferred.

[0027] The above (meth)acrylic acid ester (a-2) is not particularly limited, and examples include heptyl acrylate (Tg of -68°C when homopolymerized), 2-ethylhexyl acrylate (Tg of -70°C when homopolymerized), octyl acrylate (Tg of -65°C when homopolymerized), etc. Furthermore, examples include isononyl acrylate (Tg of -58°C when homopolymerized), isodecyl acrylate (Tg of -62°C when homopolymerized), etc. Among these, at least one selected from the group consisting of heptyl acrylate and 2-ethylhexyl acrylate is preferred, and 2-ethylhexyl acrylate is more preferred, as it makes it easier to adjust the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape to a more favorable range.

[0028] When the above (meth)acrylic polymer contains the above (meth)acrylic acid ester (a), the content of the constituent units derived from the above (meth)acrylic acid ester (a) in the above (meth)acrylic polymer is not particularly limited, but a preferred lower limit is 40% by weight. If the content of the above constituent units is 40% by weight or more, the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape can be more easily adjusted to a more preferred range, the peel performance of the adhesive tape when retransferring chip components can be improved, and the chip components can be attached more well when receiving them. A more preferred lower limit for the content of the above constituent units is 45% by weight, an even more preferred lower limit is 80% by weight, and an even more preferred lower limit is 90% by weight. The upper limit of the content of the above constituent units is not particularly limited, but a preferred upper limit is 98% by weight, and a more preferred upper limit is 95% by weight.

[0029] Furthermore, if the (meth)acrylic acid ester (a) contains the (meth)acrylic acid ester (a-1), the content of the constituent units derived from the (meth)acrylic acid ester (a-1) in the (meth)acrylic polymer is not particularly limited, but a preferred lower limit is 40% by weight. If the content of the constituent units is 40% by weight or more, the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape can be more easily adjusted to a more preferred range, the peel performance of the adhesive tape when re-transferring chip components can be improved, and the chip components can be attached more effectively when receiving them. A more preferred lower limit for the content of the constituent units is 45% by weight. While there is no particular upper limit to the content of the above constituent units, if the amount is too high, the long alkyl groups (alkyl groups with 12 or more carbon atoms) present in the side chains will crystallize at low temperatures, causing the shear storage modulus G' at a frequency of 10 Hz and -20°C to become too high. Therefore, a preferred upper limit is 80% by weight, and a more preferred upper limit is 70% by weight.

[0030] The above (meth)acrylic polymer preferably further contains a structure derived from a monomer containing a crosslinkable functional group. Because the (meth)acrylic polymer contains a structure derived from the above-mentioned crosslinkable functional group-containing monomer, the cohesive force of the adhesive layer can be adjusted by crosslinking the crosslinkable functional group, making it easier to adjust the adhesive strength and shear storage modulus G' of the adhesive layer. As a result, the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape can be adjusted to a more favorable range, the adhesive tape has improved peel performance when re-transferring chip components, and can better adhere chip components when receiving them. The above-mentioned crosslinkable functional group may or may not be crosslinked, but it is more preferable that it be crosslinked. However, even if the structure remains uncrosslinked, the cohesive force of the adhesive layer will be increased due to the interaction between the functional groups.

[0031] Examples of the above-mentioned crosslinkable functional group-containing monomers include monomers containing carboxyl groups, hydroxyl groups, epoxy groups, double bonds, triple bonds, amino groups, amide groups, nitrile groups, and the like. These crosslinkable functional group-containing monomers may be used individually or in combination of two or more. Among these, at least one selected from the group consisting of carboxyl group-containing monomers and hydroxyl group-containing monomers is preferred. Hydroxyl group-containing monomers are more preferred because crosslinking with an isocyanate-based crosslinking agent easily adjusts the shear storage modulus G' of the adhesive layer. Furthermore, the above-mentioned monomer containing a crosslinkable functional group may also contain alkyl groups, ether groups, carbonyl groups, ester groups, carbonate groups, amide groups, urethane groups, and the like.

[0032] Examples of carboxyl group-containing monomers include (meth)acrylic acid-based monomers such as (meth)acrylic acid. Examples of hydroxyl group-containing monomers include 4-hydroxybutyl (meth)acrylate and 2-hydroxyethyl (meth)acrylate. Examples of epoxy group-containing monomers include glycidyl (meth)acrylate. Examples of double bond-containing monomers include allyl (meth)acrylate and hexanediol di(meth)acrylate. Examples of triple bond-containing monomers include propargyl (meth)acrylate. Examples of amide group-containing monomers include (meth)acrylamide. Among these, 4-hydroxybutyl acrylate is more preferred because it is easier to adjust the shear storage modulus G' of the adhesive layer to the above range.

[0033] The content of the structure derived from the monomer having the crosslinkable functional group in the above (meth)acrylic polymer is not particularly limited, but from the viewpoint of adjusting the tackiness and shear storage modulus G' of the adhesive layer, the preferred lower limit of the content of the structure is 0.1% by weight and the preferred upper limit is 30% by weight. A more preferred lower limit of the content of the structure is 0.5% by weight and a more preferred upper limit is 25% by weight. Furthermore, the content of the structure derived from the hydroxyl group-containing monomer in the (meth)acrylic polymer is not particularly limited, but from the viewpoint of adjusting the tackiness and shear storage modulus G' of the adhesive layer, the preferred lower limit of the content of the structure is 1% by weight and the preferred upper limit is 20% by weight. A more preferred lower limit of the content of the structure is 3% by weight and a more preferred upper limit is 10% by weight.

[0034] The above (meth)acrylic polymer may contain carbon-carbon double bonds in its side chains. The side chain refers to the branched structural portion extending from the main chain, where the longest chain in the polymer is considered the main chain. The (meth)acrylic polymer contains carbon-carbon double bonds in its side chains, which allows the adhesive layer to be a curable adhesive layer that hardens significantly upon heating, light irradiation, or other means, resulting in a substantial decrease in adhesive strength. In such a case, the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape can be more easily adjusted to a more favorable range, resulting in improved peel performance when re-transferring chip components and better adhesion of chip components when receiving them. Examples of the curable adhesive layer include a thermosetting adhesive layer and a photocurable adhesive layer, but a photocurable adhesive layer is preferred from the viewpoint of storage stability.

[0035] To obtain the above (meth)acrylic polymer, a monomer mixture containing the above (meth)acrylic monomer and the above crosslinkable functional group-containing monomer can be copolymerized by radical reaction in the presence of a polymerization initiator. If the above-mentioned acrylic polymer contains a carbon-carbon double bond in its side chain, a carbon-carbon double bond can be introduced into the side chain of the acrylic polymer by copolymerizing the double bond-containing monomer as the crosslinkable functional group-containing monomer, for example. Alternatively, after copolymerizing a carboxyl group-containing monomer, a hydroxyl group-containing monomer, etc., as the crosslinkable functional group-containing monomer, the resulting polymer may be reacted with a compound containing a functional group that can react with the carboxyl group, hydroxyl group, etc. in the polymer, and a double bond (hereinafter also referred to as a "functional group-containing unsaturated compound"). The functional group-containing unsaturated compound is not particularly limited, and examples include isocyanate group-containing unsaturated compounds such as 2-methacryloyloxyethyl isocyanate (MOI). Conventional known methods can be used to carry out a radical reaction of the above monomer mixture, i.e., polymerization methods, such as solution polymerization (boiling point polymerization or constant temperature polymerization), emulsion polymerization, suspension polymerization, and bulk polymerization.

[0036] The hydroxyl value of the above (meth)acrylic polymer is not particularly limited, but a preferred upper limit is 45 mgKOH / g. If the above hydroxyl value is 45 mgKOH / g or less, it becomes easier to adjust the adhesive strength and shear storage modulus G' of the adhesive layer. As a result, the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape can be adjusted to a more preferred range, the adhesive tape has better peel performance when re-transferring chip components, and can better adhere chip components when receiving them. A more preferred upper limit for the above hydroxyl value is 20 mgKOH / g. The lower limit of the hydroxyl value is not particularly limited, but from the viewpoint of adjusting the adhesive strength of the adhesive layer and the shear storage modulus G' of the adhesive tape, a preferred lower limit is 1 mg KOH / g. The hydroxyl value of (meth)acrylic polymers is an indicator that represents the amount of hydroxyl groups contained in a given amount of sample. The hydroxyl value of (meth)acrylic polymers is the amount of potassium hydroxide in milligrams required to neutralize the acetic acid bonded to the hydroxyl groups after acetylating 1 g of (meth)acrylic polymer by neutralization titration. This can be calculated by measuring it based on the potentiometric titration method specified in JIS K 0070:1992.

[0037] The carbon-carbon double bond equivalent of the (meth)acrylic polymer is not particularly limited, but if it is too high, the shear storage modulus G' at a frequency of 10 Hz and -20°C becomes too high, so a preferred upper limit is 0.5 meq / g. If the carbon-carbon double bond equivalent is 0.5 meq / g or less, the shear storage modulus G' of the adhesive layer and the surface peel strength of the adhesive tape can be more easily adjusted to a more preferred range, the peel performance of the adhesive tape when re-transferring chip components can be improved, and the chip components can be attached more effectively when receiving them. A more preferred upper limit for the carbon-carbon double bond equivalent is 0.3 meq / g. The lower limit of the carbon-carbon double bond equivalents mentioned above is not particularly limited and may be 0 meq / g. The carbon-carbon double bond equivalent of a (meth)acrylic polymer is the milliequivalent (meq / g) of carbon-carbon double bonds in an unsaturated compound containing double bonds per gram of (meth)acrylic polymer, and is a calculated value derived from the amount of raw materials used. Specifically, the carbon-carbon double bond equivalent E (meq / g) can be calculated from the mass Wa (g) of the (meth)acrylic polymer, the amount of substance nb (moles) of the unsaturated compound containing double bonds contained in the (meth)acrylic polymer, and the number N (bonds) of carbon-carbon double bonds contained in one molecule of the unsaturated compound containing double bonds, using the following formula. E = nb × N × 1000 / Wa

[0038] The weight-average molecular weight (Mw) of the above (meth)acrylic polymer is not particularly limited, but a preferred upper limit is 1 million. If the weight-average molecular weight (Mw) is 1 million or less, the shear storage modulus G' and surface peel strength can be more easily adjusted to a more preferred range, the adhesive tape will have better peel performance when re-transferring chip components, and the chip components will adhere better when receiving them. A more preferred upper limit for the weight-average molecular weight (Mw) is 950,000, and an even more preferred upper limit is 900,000. The lower limit of the weight-average molecular weight (Mw) is not particularly limited, but from the viewpoint of the adhesive strength and shape retention of the adhesive layer, a preferred lower limit is 400,000, and a more preferred lower limit is 500,000. The weight-average molecular weight of (meth)acrylic polymers can be determined, for example, by GPC (Gel Permeation Chromatography) on a standard polystyrene basis. More specifically, for example, it can be measured using a Waters 2690 Separations Module as the measuring instrument, a Showa Denko GPC KF-806L column, and ethyl acetate as the solvent, with a sample flow rate of 1 mL / min and a column temperature of 40°C.

[0039] The above adhesive layer may contain a tackifying resin. Examples of the tackifying resins mentioned above include rosin ester resins, hydrogenated rosin resins, terpene resins, terpene phenol resins, coumarone indene resins, alicyclic saturated hydrocarbon resins, C5 petroleum resins, C9 petroleum resins, and C5-C9 copolymer petroleum resins. These tackifying resins may be used individually or in combination of two or more types.

[0040] The content of the tackifying resin is not particularly limited, but from the viewpoint of further improving the peeling performance when re-transferring chip components, it is preferable not to include the tackifying resin. If the tackifying resin is included, the preferred upper limit is 10 parts by weight per 100 parts by weight of the resin (e.g., (meth)acrylic polymer) that is the main component of the adhesive layer. When the content of the tackifying resin is 10 parts by weight or less, the peeling performance of the adhesive layer when re-transferring chip components becomes higher.

[0041] Preferably, the adhesive layer contains a crosslinking agent so that a crosslinked structure is formed between the main chains of the resin constituting the adhesive layer (for example, the (meth)acrylic polymer, the tackifying resin, etc.). The above crosslinking agent is not particularly limited, and examples include isocyanate-based crosslinking agents, aziridine-based crosslinking agents, epoxy-based crosslinking agents, and metal chelate-type crosslinking agents. In particular, when the (meth)acrylic polymer contains structural units derived from the hydroxyl group-containing monomer, isocyanate-based crosslinking agents are preferred because the shear storage modulus G' of the adhesive layer can be easily adjusted by crosslinking with the hydroxyl group. The amount of the crosslinking agent is preferably 0.01 to 10 parts by weight, and more preferably 0.1 to 7 parts by weight, per 100 parts by weight of the resin (for example, the (meth)acrylic polymer) that forms the main component of the adhesive layer.

[0042] If the adhesive layer is a curable adhesive layer, it may further contain polymerization initiators such as thermal polymerization initiators and photopolymerization initiators. The content of the polymerization initiator is not particularly limited, but is preferably 0.01 parts by weight or more and 5 parts by weight or less, and more preferably 0.1 parts by weight or more and 3 parts by weight or less, per 100 parts by weight of the (meth)acrylic polymer.

[0043] The above adhesive layer may further contain an inorganic filler such as fumed silica. By incorporating the above inorganic filler, the cohesive force of the adhesive layer can be increased.

[0044] The adhesive layer described above may further contain known additives such as plasticizers, resins, surfactants, waxes, and particulate fillers. These additives may be used individually or in combination of two or more.

[0045] The gel fraction of the adhesive layer described above is not particularly limited, but a preferred lower limit is 50% by weight and a preferred upper limit is 95% by weight. If the gel fraction is 50% by weight or more, the adhesive strength of the adhesive layer is adjusted to a relatively low range, making it easier to adjust the surface peel strength of the adhesive tape. As a result, the adhesive tape has better peel performance when re-transferring chip components. If the gel fraction is 95% by weight or less, it is easier to adjust the shear storage modulus G' of the adhesive layer. As a result, the adhesive tape can better adhere chip components when receiving them. A more preferred lower limit for the gel fraction is 80% by weight, a more preferred upper limit is 94% by weight, an even more preferred lower limit is 85% by weight, and an even more preferred upper limit is 93% by weight. The gel fraction of the adhesive layer can be measured by the following method. 0.1 g of only the adhesive layer (adhesive composition) is taken from the adhesive tape and immersed in 50 mL of ethyl acetate. The mixture is shaken in a shaker at 23°C and 200 rpm for 24 hours. After shaking, the ethyl acetate and the adhesive composition that has absorbed and swollen with ethyl acetate are separated using a metal mesh (mesh size #200). The separated adhesive composition is dried at 110°C for 1 hour. The weight of the adhesive composition including the metal mesh after drying is measured, and the gel fraction of the adhesive layer is calculated using the following formula. Note that if the adhesive layer is a curable adhesive layer, the gel fraction of the adhesive layer refers to the gel fraction measured for the adhesive layer before curing. Gel fraction (weight %) = 100 × (W1 - W2) / W0 (W0: initial weight of adhesive composition, W1: weight of adhesive composition including metal mesh after drying, W2: initial weight of metal mesh) However, if the above adhesive composition does not dissolve completely in ethyl acetate, a solvent such as toluene, hexane, or water may be used instead. Specifically, if the adhesive composition contains, for example, a styrene-based elastomer, toluene or hexane may be used, and if it contains polyvinyl alcohol, hot water at 90°C may be used.

[0046] The adhesive tape of the present invention may be a single-sided adhesive tape having an adhesive layer on only one side of the base material, or a double-sided adhesive tape having adhesive layers on both sides of the base material. Furthermore, since handling is improved by attaching the support and the adhesive tape of the present invention, the adhesive tape of the present invention is preferably a double-sided adhesive tape, and more preferably a double-sided adhesive tape having adhesive layers on both sides of the substrate. The support is not particularly limited and examples include glass, quartz substrate, metal plate, etc. If the adhesive tape of the present invention is a double-sided adhesive tape having adhesive layers on both sides of a substrate, the adhesive layers on both sides may be adhesive layers as described above, or one side may be an adhesive layer as described above, and the other side (the side in contact with a support, etc.) may be another adhesive layer. The other adhesive layer is not particularly limited, and conventionally known adhesive layers can be used.

[0047] The applications of the adhesive tape of the present invention are not particularly limited, but it is preferable to use it to receive a component in the process of transferring the component. The above-mentioned components are not particularly limited, but are preferably semiconductor devices. Examples of such semiconductor devices include chip components such as micro-LED chips and optical chips for image sensors. Among these, micro-LED chips are preferred. The adhesive tape of the present invention is particularly suitable for use as an adhesive tape for receiving chip components in the process of transferring chip components, which are arranged on an adhesive layer as shown in Figure 1, onto the adhesive tape. The method for transferring the chip components onto the adhesive tape of the present invention is not particularly limited, and methods such as irradiating with laser light can be employed. The method for re-transferring the chip components from the adhesive tape of the present invention onto another carrier material or drive circuit board is not particularly limited, and methods such as directly laminating another adhesive carrier material and peeling it off to transfer the components, or irradiating with laser light can be used. [Effects of the Invention]

[0048] According to the present invention, it is possible to provide an adhesive tape that can securely attach chip components when receiving them, exhibits excellent peeling performance when re-transferring chip components, and minimizes adhesive residue on chip components. [Brief explanation of the drawing]

[0049] [Figure 1] This is a schematic cross-sectional view illustrating an example of the process of transferring chip components placed on an adhesive layer onto an adhesive tape. [Figure 2] This diagram schematically illustrates a method for measuring the surface peel strength of adhesive tape. [Modes for carrying out the invention]

[0050] The embodiments of the present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0051] (Example 1) (1) Preparation of (meth)acrylic polymers 52 parts by weight of ethyl acetate was placed in a reactor equipped with a thermometer, stirrer, and condenser, and after purging with nitrogen, the reactor was heated and reflux was started. Thirty minutes after the ethyl acetate boiled, 0.08 parts by weight of azobisisobutyronitrile was added as a polymerization initiator. 94.7 parts by weight of 2-ethylhexyl acrylate, 5 parts by weight of 2-hydroxyethyl acrylate, and 0.3 parts by weight of acrylic acid were added dropwise and evenly over 1 hour and 30 minutes to allow the reaction to proceed. Thirty minutes after the end of the dropwise addition, 0.1 parts by weight of azobisisobutyronitrile was added, and the polymerization reaction was continued for a further 5 hours. By adding ethyl acetate to the reactor and cooling while diluting, a solution of (meth)acrylic polymer (hydroxyl value 24.2 mg KOH / g, double bond equivalent 0 meq / g) was obtained. The weight-average molecular weight of the obtained (meth)acrylic polymer was measured using a Waters 2690 Separations Module, a Showa Denko GPC KF-806L column, and ethyl acetate as the solvent, under conditions of a sample flow rate of 1 mL / min and a column temperature of 40°C. The weight-average molecular weight was 800,000.

[0052] (2) Manufacturing of adhesive tape To the obtained (meth)acrylic polymer solution, Coronate L-45 (manufactured by Tosoh Corporation) was added as an isocyanate crosslinking agent to 100 parts by weight of (meth)acrylic polymer, so that the solid content was 1.8 parts by weight, and the mixture was thoroughly stirred to obtain an adhesive solution. The obtained adhesive solution was coated onto a 100 μm thick polyethylene terephthalate (PET) film substrate using an applicator so that the dry film thickness was 40 μm, and the tape was dried at 110°C for 3 minutes to obtain an adhesive tape.

[0053] (3) Measurement of gel fraction 0.1 g of only the adhesive layer (adhesive composition) was taken from the adhesive tape and immersed in 50 mL of ethyl acetate. The mixture was shaken in a shaker at 23°C and 200 rpm for 24 hours. After shaking, the ethyl acetate and the adhesive composition that had absorbed and swollen with ethyl acetate were separated using a metal mesh (mesh size #200). The separated adhesive composition was dried at 110°C for 1 hour. The weight of the adhesive composition including the metal mesh after drying was measured, and the gel fraction of the adhesive layer was calculated using the following formula. Note that if the adhesive layer is a curable adhesive layer, the gel fraction of the adhesive layer refers to the gel fraction measured for the adhesive layer before curing. Gel fraction (weight %) = 100 × (W1 - W2) / W0 (W0: initial weight of adhesive composition, W1: weight of adhesive composition including metal mesh after drying, W2: initial weight of metal mesh)

[0054] (4) Measurement of shear storage modulus G' For the adhesive layer, the dynamic viscoelastic spectrum was measured from -40 to 140°C using a viscoelastic spectrometer (IT Measurement Control Co., Ltd., DVA-200) under the conditions of a simple heating mode with a heating rate of 5°C / min and a frequency of 10 Hz. The shear storage modulus G' at -20°C and 23°C at a frequency of 10 Hz was determined. Note that if the adhesive layer is a curable adhesive layer, the shear storage modulus G' of the adhesive layer refers to the shear storage modulus G' measured for the adhesive layer before curing.

[0055] (5) Measurement of surface peel strength (adhesive area 10 mm x 10 mm, against SUS) Figure 2 shows a schematic diagram illustrating the method for measuring the surface peel strength of adhesive tape. First, the adhesive tape 8 was cut to 10mm x 10mm. The adhesive layer of the cut adhesive tape 8 was attached to a SUS jig 12 (SUS304) and pressed at 0.3 MPa for 10 seconds. One side of a measuring double-sided adhesive tape 11 (manufactured by Sekisui Chemical Co., Ltd., product name #560) was attached to the back of the adhesive tape 8 attached to the SUS jig 12. The other side of the measuring double-sided adhesive tape 11 was attached to a glass plate 10 with a thickness of 5 mm. Then, the glass plate 10 was fixed to a tensile testing machine (manufactured by Shimadzu Corporation, AGS-X). Note that when measuring the surface peel strength of the adhesive tape 8 after UV irradiation, before fixing the glass plate 10 to the tensile testing machine, a UV lamp with a wavelength of 365 nm was used to measure the intensity at 10 mW / cm². 2 , irradiation amount 2500mJ / cm 2 Under these conditions, the adhesive layer of the adhesive tape 8 was cured by irradiating it with ultraviolet light from the glass plate 10 side. Under conditions of room temperature 23°C and relative humidity 50%, a tensile test was performed using a tensile testing machine (Shimadzu Corporation, AGS-X) to pull a SUS jig 12 vertically (in the direction of the arrow in the figure) at a peeling speed of 200 mm / min, and the surface peel strength of the adhesive tape was measured. Note that the surface peel strength represents the maximum peel strength.

[0056] (Examples 2-9, 13-16, Comparative Examples 1-3, 5) An adhesive tape was obtained in the same manner as in Example 1, except that the composition and weight-average molecular weight of the (meth)acrylic polymer, the type and amount of the crosslinking agent, and the thickness of the adhesive layer were changed as shown in Tables 1 and 2. As crosslinking agents, we also used Coronate HX (manufactured by Tosoh Corporation), an isocyanate-based crosslinking agent, and Tetrad C (manufactured by Mitsubishi Gas Chemical Company), an epoxy-based crosslinking agent.

[0057] (Examples 10-12, Comparative Examples 4, 6, 7) A solution of (meth)acrylic polymer was obtained in the same manner as in Example 1, except that the composition and weight-average molecular weight of the (meth)acrylic polymer were changed as shown in Tables 1 and 2. To 100 parts by weight of the resin solids of the obtained (meth)acrylic polymer solution, 2-methacryloyloxyethyl isocyanate (MOI), as an isocyanate group-containing unsaturated compound, was added in the amounts shown in Tables 1-2, and an addition reaction was carried out at 60°C for 2 hours to obtain a solution of (meth)acrylic polymer containing carbon-carbon double bonds in its side chains. Subsequently, the type and amount of crosslinking agent, the thickness of the adhesive layer, etc. were changed as shown in Tables 1 and 2, and an adhesive tape was obtained in the same manner as in Example 1, except that omnirad651 (manufactured by IGM Resins BV), a photopolymerization initiator, was added in the amount shown in Tables 1 and 2.

[0058] <Rating> The adhesive tapes obtained in the examples and comparative examples were evaluated as follows. The results are shown in Tables 1 and 2.

[0059] (1) Evaluation of the transfer performance of chip components (adhesion of chip components) In addition to the adhesive tape obtained, a single-sided adhesive tape for testing was prepared. A single-sided adhesive tape for testing was attached to the Si chip side of a wafer on which 10 Si chips (500 μm x 500 μm square, 50 μm thick) were arranged. Then, the wafer was peeled off, and the Si chips were placed on the single-sided adhesive tape for testing. A single-sided adhesive tape for testing, on which Si chips were placed, was placed opposite an adhesive tape obtained in an example or comparative example. Using a semiconductor solid-state laser, a 4W, 4KHz laser beam with a wavelength of 365nm was irradiated onto each Si chip from the substrate side of the single-sided adhesive tape for testing. The Si chips were peeled off and transferred onto the adhesive tape. The transfer performance of the chip components was evaluated as follows: "◎" if 10 Si chips adhered to the adhesive tape, "〇" if 8 to 9 chips adhered, and "×" if 7 or fewer Si chips adhered.

[0060] (2) Retransfer performance and adhesive residue during retransfer The resulting adhesive tape was attached to the Si chip side of a wafer on which 10 Si chips (500 μm x 500 μm square, 50 μm thick) were arranged. The wafer was then peeled off to position the Si chips onto the adhesive tape. In Examples 10-12 and Comparative Examples 4, 6, and 7, where the adhesive layer was a curable adhesive layer (photocurable adhesive layer), a UV lamp with a wavelength of 365 nm was used, with an intensity of 10 mW / cm². 2 , irradiation amount 2500mJ / cm 2 The adhesive layer was cured by irradiating the substrate with ultraviolet light under these conditions. The adhesive tape on which the Si chips were placed was placed opposite the adhesive surface of a protective tape (6312C, manufactured by Sekisui Chemical Co., Ltd.), and the Si chips were pressed onto the protective tape by applying pressure with a 2kg roller at a speed of 300mm / min. After that, the protective tape was peeled off to remove the Si chips from the adhesive tape and transfer them onto the protective tape. The re-transfer performance was evaluated as follows: "◎" if 10 Si chips could be placed on the protective tape from the adhesive tape, "〇" if 8 to 9 Si chips could be placed, and "×" if 7 or fewer Si chips could be placed. Furthermore, the surface of the Si chip peeled off the adhesive tape was observed under a microscope, and adhesive residue was evaluated by marking "○" if no residue was observed and "×" if residue was observed.

[0061] [Table 1]

[0062] [Table 2]

[0063] BA: Butyl acrylate HPA: Heptyl acrylate 2-EHA:2-Ethylhexylacrylate LA: Lauryl acrylate 2-HEA:2-hydroxyethyl acrylate 4-HBA:4-hydroxybutyl acrylate AAc: Acrylic acid AAm: Acrylamide [Industrial applicability]

[0064] According to the present invention, it is possible to provide an adhesive tape that can securely attach chip components when receiving them, exhibits excellent peeling performance when re-transferring chip components, and minimizes adhesive residue on chip components. [Explanation of Symbols]

[0065] 1. Chip component 2. Adhesive layer 3 Base material 4. Adhesive layer 5 Base material 8 Adhesive tape 9. Laminate of substrate and adhesive layer 10 glass plates 11. Double-sided adhesive tape for measurement 12 SUS jig

Claims

1. An adhesive tape comprising at least one base material and at least one adhesive layer, The adhesive layer has a shear storage modulus G' of 1 MPa or less at a frequency of 10 Hz and -20°C, and a thickness of 30 μm or more. The adhesive layer is an acrylic adhesive layer containing a (meth)acrylic polymer and a crosslinking agent. The (meth)acrylic polymer contains 80% by weight or more of constituent units derived from (meth)acrylic acid ester (a) having a glass transition temperature (Tg) of 0°C or less when homopolymerized, and 0.1% by weight or more of constituent units derived from a crosslinkable functional group-containing monomer. The content of the crosslinking agent is 2 parts by weight or less per 100 parts by weight of the (meth)acrylic polymer. The adhesive tape has a surface peel strength of 0.5 MPa or less on SUS over an application area of ​​10 mm x 10 mm. An adhesive tape characterized by the following features.

2. The adhesive tape according to claim 1, characterized in that the adhesive layer has a shear storage modulus G' of 0.3 MPa or less at a frequency of 10 Hz and -20°C.

3. The adhesive tape according to claim 1, characterized in that the adhesive layer has a shear storage modulus G' of 0.04 MPa or less at a frequency of 10 Hz and 23°C.

4. The adhesive tape according to claim 1, characterized in that the adhesive layer has a thickness of 40 μm or more.

5. The adhesive tape according to claim 1, characterized in that the surface peel strength against SUS at an application area of ​​10 mm x 10 mm is 0.01 MPa or more.

6. The adhesive tape according to claim 1, characterized in that the surface peel strength against SUS at an application area of ​​10 mm x 10 mm is 0.2 MPa or less.

7. The adhesive tape according to claim 1, characterized in that the (meth)acrylic polymer has a hydroxyl value of 45 mgKOH / g or less.

8. The adhesive tape according to claim 1, characterized in that the (meth)acrylic polymer contains 40% by weight or more of constituent units derived from a (meth)acrylic acid ester (a-1) having an alkyl group having 12 or more carbon atoms and having a glass transition temperature (Tg) of 0°C or less when it is a homopolymer.

9. The adhesive tape according to claim 8, characterized in that the (meth)acrylic acid ester (a-1) having an alkyl group having 12 or more carbon atoms and having a glass transition temperature (Tg) of 0°C or less when it is a homopolymer contains lauryl (meth)acrylate.

10. The adhesive tape according to claim 1, characterized in that the (meth)acrylic polymer contains 90% by weight or more of constituent units derived from a (meth)acrylic acid ester (a) whose glass transition temperature (Tg) when used as the homopolymer is 0°C or lower.

11. The adhesive tape according to claim 1, characterized in that the aforementioned crosslinkable functional group-containing monomer includes a hydroxyl group-containing monomer.

12. The adhesive tape according to claim 1, characterized in that the adhesive layer is a photocurable adhesive layer.

13. The adhesive tape according to claim 1, characterized in that the (meth)acrylic polymer contains a carbon-carbon double bond in its side chain.

14. The adhesive tape according to claim 13, characterized in that the (meth)acrylic polymer has a carbon-carbon double bond equivalent of 0.5 meq / g or less.

15. The adhesive tape according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14, characterized in that it is used to receive the parts in the process of transferring the parts.

16. The adhesive tape according to claim 15, characterized in that the aforementioned component is a semiconductor device.

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