KR102205230B1 - Pressure-sensitive adhesive tape - Google Patents

Abstract

It is an adhesive tape that can be used as a dicing tape, the standard deviation σ of the thickness variation of the adhesive tape is small, and the stress against expansion or pin lifting is uniform within the tape surface.
The adhesive tape of the present invention is an adhesive tape having an adhesive layer on at least one side of a substrate, and the standard deviation σ of the thickness variation of the adhesive tape is 2.0 µm or less.

Description

Adhesive tape {PRESSURE-SENSITIVE ADHESIVE TAPE}

The present invention relates to an adhesive tape.

In the dicing of a semiconductor, by dicing the semiconductor wafer on a dicing tape (adhesive tape), the semiconductor wafer is divided into small pieces (chips) to form chips, the chips are collected on a dicing tape, and then It is used in a subsequent step (for example, see Patent Document 1). As a method of collecting chips on a dicing tape, a stick called a pin or needle, etc. is used from the side of the dicing tape to which the chips are not mounted (so-called ``pin lifting''), and then a suction jig called a collet. The chips are separated by adsorption on the dicing tape and collected.

Here, since the interval between the chips immediately after dicing is very small, such as only a few hundred μm, if the chips are to be collected on the dicing tape as they are, they may collide with other chips (especially adjacent chips). The chip is damaged.

Therefore, in dicing of semiconductors, after dicing, before the chips are collected on the dicing tape, in the state where the chips are mounted on the dicing tape, the dicing tape is expanded (stretched) to increase the gap between the chips. In general, the chips are collected on a dicing tape.

However, even by such a method, defects may occur during collection. For this reason, further improvement is required when dicing a semiconductor.

As a typical example of such a defect, when the chips are adsorbed and separated on a dicing tape by a collet, it is not possible to accurately adsorb and separate them.

As a cause of the above defect, it is considered that the adhesive force between the dicing tape and the chip is too strong. However, even if the adhesive force between the dicing tape and the chip is weakened, the above defect is not eliminated.

Japanese Patent Publication No. 2005-019607

The inventor of the present invention has conducted various investigations on the cause of the inability to be accurately suction-separated when the chips are suction-separated from the dicing tape by a collet. Then, the examination was repeated, paying attention to the positional shift between the collet suction surface and the chip. As a result, it was thought that it was important that the stress of the dicing tape against expansion or pin lifting was uniform within the tape surface. In addition, in order for the stress of the dicing tape against expansion or pin lifting to be uniform within the tape surface, it is thought that it is important that the thickness of the dicing tape does not fluctuate within the surface. The standard deviation? Of is strictly adjusted to a predetermined level, and thus the present invention has been completed.

That is, the subject of the present invention is an adhesive tape that can be used as a dicing tape, and the standard deviation σ of the thickness variation of the adhesive tape is small, and the stress against expansion or pin lifting is uniform within the tape surface. It is to provide an adhesive tape.

The adhesive tape of the present invention,

It is an adhesive tape having an adhesive layer on at least one side of the substrate,

The standard deviation σ of the variation in thickness of the adhesive tape is 2.0 µm or less.

In a preferred embodiment, the average thickness of the adhesive tape is 20 µm to 120 µm.

In a preferred embodiment, the ratio of the modulus at the time of 100% stretching in the MD direction of the adhesive tape and the modulus at the time of 100% stretching in the TD direction (100% modulus in MD direction/100% modulus in TD direction) of the adhesive tape is 0.5 to 1.9.

In a preferred embodiment, the standard deviation σ of the thickness variation of the substrate is 2.0 µm or less.

In a preferred embodiment, the average thickness of the substrate is 20 µm to 120 µm.

In a preferred embodiment, the maximum elongation measured according to JIS-K-7127 (1999) described above is 100% or more.

In a preferred embodiment, the substrate is a plastic film.

In a preferred embodiment, the plastic film contains at least one selected from polyvinyl chloride, polyolefin, and ethylene-vinyl acetate copolymer.

In a preferred embodiment, the pressure-sensitive adhesive layer is provided on one side of the substrate, and a non-adhesive layer is provided on the side opposite to the pressure-sensitive adhesive layer of the substrate.

In a preferred embodiment, the non-adhesive layer is a mixed layer of silicone and (meth)acrylic polymer.

In a preferred embodiment, the mixing ratio of the silicone and the (meth)acrylic polymer in the non-adhesive layer is, by weight, silicone:(meth)acrylic polymer = 1:50 to 50:1.

In a preferred embodiment, the non-adhesive layer has a phase separation structure.

In a preferred embodiment, the thickness of the non-adhesive layer is 0.01 μm to 10 μm.

In a preferred embodiment, the pressure-sensitive adhesive layer contains at least one (meth)acrylic polymer.

In a preferred embodiment, a release liner is provided on the surface of the pressure-sensitive adhesive layer.

In a preferred embodiment, the adhesive tape of the present invention is used for semiconductor processing.

In a preferred embodiment, the adhesive tape of the present invention is used for LED dicing.

According to the present invention, an adhesive tape that can be used as a dicing tape, wherein the standard deviation σ of the thickness variation of the adhesive tape is small, and the stress against expansion or pin lifting is uniform within the tape surface. Can provide.

1 is a schematic diagram showing an alignment state of chips after expansion when the thickness accuracy is good.
Fig. 2 is a schematic diagram showing an alignment state of chips after expansion when the thickness accuracy is poor.
Fig. 3 is a photographic view of an SEM showing a state on the surface side of a non-adhesive layer in the adhesive tape of the present invention.
Fig. 4 is a photograph of an SEM showing a state of a cross-section of a non-adhesive layer in the adhesive tape of the present invention.
Fig. 5 is a photographic view of an SEM showing a state on the cross-section side of a non-adhesive layer in the adhesive tape of the present invention with explanation attached.

The adhesive tape of the present invention includes an adhesive layer on at least one side of the substrate. The adhesive tape of the present invention may have an adhesive layer on both sides of a base material, or may include an adhesive layer on one side of the base material.

In the adhesive tape of the present invention, the standard deviation σ of the variation in thickness is 2.0 µm or less, preferably 1.9 µm or less, more preferably 1.7 µm or less, still more preferably 1.5 µm or less, and particularly preferably It is 1.2㎛ or less. By adjusting the standard deviation σ of the thickness fluctuation of the adhesive tape of the present invention within the above range, the stress of the adhesive tape of the present invention against expansion or pin lifting can be made uniform within the tape surface. In the adhesive tape of the present invention, since the thickness fluctuation is small and the thickness accuracy is good, as shown in Fig. 1, when the adhesive tape of the present invention is used as a dicing tape, in dicing of a semiconductor, dicing In the case where the dicing tape 200 is expanded (stretched) and the gap between the chips 100 is widened, in the state where the chips are mounted on the dicing tape before collecting the chips on the dicing tape later, chips ( The position of 100) does not occur and a well-aligned chip can be obtained. On the other hand, if the thickness fluctuation of the adhesive tape is large, the thickness accuracy is deteriorated. As shown in Fig. 2, when the adhesive tape of the present invention is used as a dicing tape, in dicing of a semiconductor, the chip is die after dicing. The position of the chips 100 when the dicing tape 200 is expanded (stretched) to increase the gap between the chips 100 before collecting on the dicing tape, while the chips are mounted on the dicing tape. Misalignment may occur and, for example, poor pickup may occur. In particular, since the LED chip is small, the position of the chip is liable to be shifted. In addition, the measurement method of the standard deviation σ of the thickness fluctuation will be described later.

In addition, as a method of measuring the thickness variation, any suitable method can be adopted, such as measuring the thickness of a plurality of arbitrary points in the surface of the measurement object and performing statistical processing. As a method of measuring such thickness, for example, a method in which a micrometer, a micro vernier caliper, a dial gauge, etc. involve physical contact; A non-contact method of measuring transmittance or reflectance of α-rays, X-rays, infrared rays, electromagnetic waves, and the like on a measurement object; A method of cutting a measurement object into an arbitrary measurement location and observing it with an optical microscope or an electron microscope; And the like, and a combination of these may be employed.

The average thickness of the adhesive tape of the present invention is preferably 20 µm to 120 µm, more preferably 30 µm to 120 µm, and still more preferably 40 µm to 120 µm. By adjusting the average thickness of the adhesive tape of the present invention within the above range, the stress of the adhesive tape of the present invention against expansion or pin lifting can be made more uniform within the tape surface. In addition, when the average thickness of the adhesive tape of the present invention is too small, there is a concern that handling properties may deteriorate, and in particular, the bonding operation may become difficult. If the average thickness of the adhesive tape of the present invention is too large, there is a concern that the followability to deformation such as stretching may be deteriorated.

In the adhesive tape of the present invention, the ratio of the modulus at 100% tensile in the MD direction and the modulus at 100% tensile in the TD direction (100% modulus in MD direction/100% modulus in TD direction) is preferably 0.5 to 1.9. , More preferably 0.5 to 1.8, still more preferably 0.8 to 1.6, and particularly preferably 1.0 to 1.5. By adjusting the ratio (100% modulus in the MD direction/100% modulus in the TD direction) within the above range, the stress of the adhesive tape of the present invention against expansion or pin lifting can be made more uniform within the tape surface.

<material>

As a factor causing the thickness variation of the adhesive tape of the present invention, various factors such as variation in the thickness of the substrate, variation in the thickness of the adhesive layer, and variation in the thickness of the non-adhesive layer that can be provided on the opposite side of the adhesive layer of the substrate are considered. .

Among the above factors, the factor that has the greatest influence on the variation in the thickness of the adhesive tape is the variation in the thickness of the substrate. Because, among the constituent elements of the adhesive tape, the base material is the most strongly loaded against the stress of the expansion or pin lifting, so if the thickness variation of the base material is large, the adhesive tape of the present invention against the expansion or pin lifting This is because there is a high possibility that the stress will become uneven within the tape surface. In addition, the pressure-sensitive adhesive layer or the non-adhesive layer is installed by applying it to the surface of the substrate, but if the thickness of the substrate is large, no matter how much the pressure-sensitive adhesive layer or the non-adhesive layer is applied, it is affected by the variation in the thickness of the substrate. As a result, thickness fluctuations also occur in the pressure-sensitive adhesive layer or the non-adhesive layer.

For the reasons described above, the standard deviation σ of the variation in thickness of the substrate is preferably 2.0 µm or less, more preferably 1.8 µm or less, further preferably 1.6 µm or less. By adjusting the standard deviation σ of the variation of the thickness of the substrate within the above range, the stress of the adhesive tape of the present invention against expansion or pin lifting can be made more uniform within the tape surface. A method of measuring the standard deviation σ of the thickness fluctuation will be described later.

The average thickness of the substrate is preferably 20 µm to 120 µm, more preferably 30 µm to 120 µm, and still more preferably 40 µm to 120 µm. By adjusting the average thickness of the substrate of the present invention to fall within the above range, the stress of the adhesive tape of the present invention to expand or pin lift can be made more uniform within the tape surface. In addition, when the average thickness of the base material is too small, there is a fear that handling properties may deteriorate, and in particular, when the adhesive tape is formed, the bonding operation may become difficult. If the average thickness of the substrate is too large, there is a concern that the followability to deformation such as stretching may be deteriorated.

The substrate has a maximum elongation measured according to JIS-K-7127 (1999), preferably 100% or more, and more preferably 200% to 1000%. By using a substrate that exhibits such a maximum elongation, the stress of the adhesive tape of the present invention to expand or pin lift can be made more uniform within the tape surface. In addition, by using the base material exhibiting such maximum elongation, it is possible to impart appropriate extensibility to the adhesive tape of the present invention, and, for example, the followability to the adherend can be improved.

As the substrate, as long as it satisfies the above characteristics, any suitable material can be selected within a range that does not impair the effects of the present invention. As such a base material, Preferably it is a plastic film.

The plastic film can contain any suitable resin material. As such a resin material, Preferably, for example, polyvinyl chloride, polyolefin, ethylene-vinyl acetate copolymer, polyester, polyimide, polyamide, etc. are mentioned, More preferably, polyvinyl chloride, polyolefin, Ethylene-vinyl acetate copolymer is mentioned, More preferably, polyvinyl chloride is mentioned. Since polyvinyl chloride is excellent in stress relaxation properties, it can be particularly suitably used for adhesive tapes used for semiconductor processing such as LED dicing.

As the content ratio of the resin material in the plastic film, any appropriate content ratio can be set depending on the purpose and use. Such a content ratio is, for example, preferably 50% by weight to 100% by weight, more preferably 60% by weight to 100% by weight, and still more preferably 70% by weight to 100% by weight.

A plasticizer may be contained in the plastic film. The content ratio of the plasticizer in the plastic film is preferably 0.5% by weight to 50% by weight, and more preferably 1.0% by weight to 40% by weight, based on the resin material in the plastic film. By including a plasticizer in the above-described content ratio in the plastic film, the stress of the adhesive tape of the present invention to expand or pin lift can be made more uniform within the tape surface. Moreover, by including a plasticizer in the said content ratio in a plastic film, the followability of the adhesive tape of this invention with respect to deformation|transformation, such as stretching, becomes more favorable.

Examples of the plasticizer include phthalic acid ester, trimellitic acid ester (Dinippon Ink Co., Ltd., W-700, trimellitic trioctyl, etc.), adipic acid ester (manufactured by J Plus, Inc., D620, dioctyl adipate, diisononyl adipate, etc.), phosphate esters (tricresyl phosphate, etc.), adipic esters, citrate esters (tributyl acetyl citrate, etc.), sebacic acid ester, aceric acid ester, male Acid esters, benzoic acid esters, polyether polyesters, epoxy polyesters (epoxylated soybean oil, epoxidized linseed oil, etc.), polyesters (such as low molecular weight polyesters containing carboxylic acids and glycols), and the like. In the present invention, it is preferable to use an ester plasticizer. Only 1 type may be sufficient as a plasticizer, and 2 or more types may be sufficient as it.

In the plastic film, any suitable other component may be contained within a range not impairing the effects of the present invention.

The inventors of the present invention have found that a substrate having a small standard deviation σ of thickness variation and high thickness accuracy can be obtained by strictly devising a manufacturing method thereof.

The substrate can be manufactured by any suitable manufacturing method within the range in which the effects of the present invention can be expressed. Examples of such manufacturing methods include injection molding, extrusion molding, inflation molding, calendering, and blow molding. Among these, in order to obtain a base material with high thickness accuracy due to a small standard deviation σ of thickness fluctuations, calendering is preferable.

As the calendering, any suitable molding machine can be adopted depending on the number of calender rolls and the batch type. As such a molding machine, for example, four L-types, four inverse L-types, and four Z-types, an inclined type modified from these, and six types with additional rolls for more stability are generally mentioned.

In order to obtain a base material having a particularly high thickness accuracy because the standard deviation σ of the thickness fluctuation is particularly small, it is important to strictly control the conditions of calendering.

One preferred means for obtaining a substrate having a particularly small standard deviation σ of thickness fluctuation and having particularly high thickness accuracy is controlling the fluctuation of the compound temperature of the final bank to within ±5% in calender molding. In calendering, by controlling the fluctuation of the compound temperature of the final bank to within ±5%, the standard deviation σ of the thickness fluctuation is particularly small, so that a substrate having particularly high thickness accuracy can be obtained, and the present invention for expansion or pin lifting The stress of the adhesive tape can be made more uniform within the tape surface.

As another preferred means for obtaining a substrate with particularly high thickness accuracy due to a particularly small standard deviation σ of thickness fluctuation, in calendering, the temperature difference between the last 3 rolls (three consecutive rolls of the second half including the last roll) is determined. Controlling within ±20%, preferably within ±18%, more preferably within ±16%, and particularly preferably within ±15% is mentioned. In calender molding, by controlling the temperature difference of the last three rolls (three consecutive rolls in the second half including the last roll) within the above range, the standard deviation σ of the thickness fluctuation is particularly small, so that a substrate with particularly high thickness accuracy can be obtained. In addition, the stress of the adhesive tape of the present invention to expand or pin lift may be more uniform within the tape surface.

In the present invention, in order to obtain a substrate having particularly high thickness accuracy because the standard deviation σ of the thickness fluctuation is particularly small, the above two means are particularly preferably mentioned.

In order to obtain a substrate having particularly high thickness accuracy due to a particularly small standard deviation σ of thickness variation, it is also effective to control the compound temperature within a range of 140° to 220° in calendering.

In order to obtain a substrate having a particularly high thickness accuracy because the standard deviation σ of the thickness fluctuation is particularly small, it is also effective to control the fluctuation of the rotation speed of each roll to within ±5% in calender forming.

<Adhesive layer>

The thickness of the pressure-sensitive adhesive layer is preferably 1.0 µm to 30 µm, more preferably 1.0 µm to 20 µm, and still more preferably 3.0 µm to 15 µm. When the thickness of the pressure-sensitive adhesive layer is less than 1.0 µm, there is a fear that sufficient adhesive strength cannot be expressed. When the thickness of the pressure-sensitive adhesive layer is larger than 30 μm, depending on the application, the adhesive strength becomes too large, and there is a fear that the adherend may be crushed during peeling or the like.

As the material for the pressure-sensitive adhesive layer, any suitable pressure-sensitive adhesive can be employed within a range that does not impair the effects of the present invention.

As a material for the pressure-sensitive adhesive layer, for example, (meth)acrylic polymer; caoutchouc; Special natural rubber grafted with monomers such as methyl methacrylate; Synthetic rubbers such as SBS, SBR, SEPS, SIS, SEBS, polybutene, polyisobutene, polyisobutylene and butyl rubber; And the like. Among these, at least one (meth)acrylic polymer is preferable from the viewpoint of having little residual adhesive to the adherend after peeling, having high cohesion, and excellent transparency.

When the pressure-sensitive adhesive layer contains a (meth)acrylic polymer, the content ratio of the (meth)acrylic polymer in the pressure-sensitive adhesive layer can be appropriately set depending on the purpose.

The (meth)acrylic polymer is a resin composed of a monomer component containing a (meth)acrylic monomer as a main monomer. The content ratio of the (meth)acrylic monomer in the monomer component constituting the (meth)acrylic polymer is preferably 50% by weight or more, more preferably 70% by weight to 100% by weight, even more preferably 90% by weight to It is 100% by weight, particularly preferably 95% by weight to 100% by weight. Among the monomer components, the number of monomers may be one or two or more.

As a (meth)acrylic monomer, Preferably, (meth)acrylic acid ester and (meth)acrylic acid are mentioned.

As (meth)acrylic acid ester, a (meth)acrylic acid alkyl ester of an alkyl group (including a cycloalkyl group) having 1 to 30 carbon atoms, a hydroxyl group-containing (meth)acrylic acid ester, etc. are mentioned, for example. The number of (meth)acrylic acid esters may be one, or two or more.

Examples of the (meth)acrylate alkyl ester of an alkyl group having 1 to 30 carbon atoms (including a cycloalkyl group) include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, Butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, (meth) Cyclohexyl acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isoctyl (meth)acrylate, nonyl (meth)acrylate, isonyl (meth)acrylate, and (meth)acrylic acid Decyl, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, octadecyl (meth)acrylate , (Meth)acrylate alkyl esters of alkyl groups (including cycloalkyl groups) having 1 to 30 carbon atoms, such as nonadecyl (meth)acrylate, ecosyl (meth)acrylate, lauryl (meth)acrylate, and the like. Among these (meth)acrylic acid esters, it is preferably a (meth)acrylic acid alkyl ester of an alkyl group having 2 to 20 carbon atoms (including a cycloalkyl group), and more preferably an alkyl group having 4 to 18 carbon atoms (including a cycloalkyl group) It is (meth)acrylic acid alkyl ester of.

As a hydroxyl group-containing (meth)acrylic acid ester, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. are mentioned, for example.

The monomer component constituting the (meth)acrylic polymer preferably contains at least one selected from a hydroxyl group-containing monomer and a carboxyl group-containing monomer in order to sufficiently express the effect as an adhesive. More preferably, it is a carboxyl group-containing monomer. Further, the monomer component constituting the (meth)acrylic polymer may contain acrylonitrile in order to sufficiently express the effect as an adhesive.

As a hydroxyl-containing monomer, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, allyl alcohol, etc. are mentioned, for example. The number of hydroxyl-containing monomers may be one, or two or more.

As a carboxyl group-containing monomer, (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, crotonic acid, maleic acid, fumaric acid, itaconic acid, etc. are mentioned, for example. The number of carboxyl group-containing monomers may be one, or two or more.

When the monomer component constituting the (meth)acrylic polymer contains a hydroxyl group-containing monomer, the content ratio of the hydroxyl group-containing monomer in the monomer component constituting the (meth)acrylic polymer is preferably 0.1% to 20% by weight And more preferably 0.1% to 10% by weight. When the monomer component constituting the (meth)acrylic polymer contains a carboxyl group-containing monomer, the content ratio of the carboxyl group-containing monomer in the monomer component constituting the (meth)acrylic polymer is preferably 0.1% to 20% by weight And more preferably 0.1% to 10% by weight. In this way, the monomer component constituting the (meth)acrylic polymer contains at least one selected from a hydroxyl group-containing monomer and a carboxyl group-containing monomer, so that when a crosslinking agent is used, a crosslinking reaction with the crosslinking agent is efficiently generated. It becomes possible, and the effect as an adhesive can be fully expressed. In addition, by adjusting the content ratio of the hydroxyl group-containing monomer in the monomer component constituting the (meth)acrylic polymer or the carboxyl group-containing monomer in the monomer component constituting the (meth)acrylic polymer so as to fall within the above range, peeling It is possible to effectively prevent crushing of the adherend during operation. When the content ratio of the hydroxyl group-containing monomer in the monomer component constituting the (meth)acrylic polymer or the carboxyl group-containing monomer in the monomer component constituting the (meth)acrylic polymer is too much than the above range, the adhesive strength It becomes too large, and there is a possibility that blocking is likely to occur, and there is a concern that crushing of the adherend is likely to occur during the peeling operation.

The pressure-sensitive adhesive layer preferably contains a crosslinking agent. When the pressure-sensitive adhesive layer contains a cross-linking agent, the content ratio of the cross-linking agent in the pressure-sensitive adhesive layer can be appropriately set according to the purpose, but preferably 0.1 to 100 parts by weight of the main resin component (preferably, (meth)acrylic polymer) It is from parts by weight to 20 parts by weight. By making the content ratio of the crosslinking agent in the pressure-sensitive adhesive layer fall within the above range, an appropriate crosslinking reaction can be caused, and crushing of the adherend during the peeling operation can be effectively prevented.

Examples of the crosslinking agent include epoxy crosslinking agents, isocyanate crosslinking agents, melamine crosslinking agents, peroxide crosslinking agents, metal alkoxide crosslinking agents, metal chelate crosslinking agents, metal salt crosslinking agents, carbodiimide crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents And amine crosslinking agents. Among these crosslinking agents, a melamine-based crosslinking agent, an epoxy-based crosslinking agent, and an isocyanate-based crosslinking agent are preferable because the effects of the present invention can be sufficiently expressed. Further, the crosslinking agent may be appropriately selected as necessary, and may be one type or a mixture of two or more types.

The pressure-sensitive adhesive layer may contain a plasticizer. When the pressure-sensitive adhesive layer contains a plasticizer, the content ratio of the plasticizer in the pressure-sensitive adhesive layer can be appropriately set depending on the purpose, but from 0.1 parts by weight to 100 parts by weight of the main resin component (preferably, (meth)acrylic polymer). It is 70 parts by weight. By making the content ratio of the plasticizer in the pressure-sensitive adhesive layer fall within the above range, it becomes possible to more effectively express the effects of the present invention. If the content of the plasticizer in the pressure-sensitive adhesive layer is greater than 70 parts by weight with respect to 100 parts by weight of the main resin component (preferably, the (meth)acrylic polymer), the pressure-sensitive adhesive layer becomes too flexible, resulting in residual adhesive or contamination of the adherend. There is a fear that it will be more likely to occur.

As the plasticizer, for example, a phthalic acid ester system, a trimellitic acid ester system (manufactured by Dai Nippon Ink Co., Ltd., W-700, trioctyl trimellitic acid, etc.), an adipic acid ester system (manufactured by J Plus Corporation, D620, dioctyl adipate, diisononyl adipate, etc.), phosphate esters (tricresyl phosphate, etc.), adipic esters, citrate esters (tributyl acetyl citrate, etc.), sebacic acid ester, aceric acid ester, male Acid esters, benzoic acid esters, polyether polyesters, epoxy polyesters (epoxylated soybean oil, epoxidized linseed oil, etc.), polyesters (such as low molecular weight polyesters containing carboxylic acids and glycols), and the like. In the present invention, it is preferable to use an ester plasticizer. Only 1 type may be sufficient as a plasticizer, and 2 or more types may be sufficient as it.

The pressure-sensitive adhesive layer may contain any suitable catalyst in order to promote a crosslinking reaction or the like. When the pressure-sensitive adhesive layer contains a catalyst, the content ratio of the catalyst in the pressure-sensitive adhesive layer can be appropriately set depending on the purpose, but the main resin component (preferably, the (meth)acrylic polymer) 100 parts by weight, 0.01 parts by weight to It is 10 parts by weight. By making the content ratio of the catalyst in the pressure-sensitive adhesive layer fall within the above range, it becomes possible to more effectively express the effects of the present invention.

Examples of such catalysts include tetraisopropyl titanate, tetra-n-butyl titanate, tin octylate, lead octylate, cobalt octylate, zinc octylate, calcium octylate, lead naphthenate, cobalt naphthenate, dibutyl Organometallic compounds such as tin diacetate, dibutyl tin dioctoate, dibutyl tin dilaurate, dioctyl tin dilaurate, and dibutyl tin maleate; Basic compounds such as butylamine, dibutylamine, hexylamine, t-butylamine, ethylenediamine, isophoronediamine, imidazole, lithium hydroxide, potassium hydroxide, and sodium methylate; acidic compounds such as p-toluenesulfonic acid, trichloroacetic acid, phosphoric acid, monoalkylphosphoric acid, dialkylphosphoric acid, phosphoric acid ester of β-hydroxyethylacrylate, monoalkylphosphorous acid and dialkylphosphorous acid; And the like. One type of catalyst may be sufficient, and two or more types may be used.

In order to further express the effects of the present invention, the pressure-sensitive adhesive layer has an SP value of preferably 9.0 (cal/cm 3) ^0.5 to 12.0 (cal/cm 3) ^0.5 , more preferably 9.5 (cal/cm 3) ^0.5 To 11.0 (cal/cm 3) ^0.5 . The SP value is a solubility parameter calculated by the Small equation. The calculation of the SP value can be performed by a method described in a known document (for example, Journal of Applied Chemistry, 3, 71, 1953., etc.).

Any suitable additive may be contained in the pressure-sensitive adhesive layer within a range that does not impair the effects of the present invention. As such an additive, an ultraviolet absorber, a filler, an anti-aging agent, a tackifier, a pigment, a dye, a silane coupling agent, etc. are mentioned, for example.

The adhesive tape of the present invention may be provided with a release liner on the surface of the adhesive layer.

As the release liner, any suitable separator can be employed. Examples of such a release liner include a base material having a release layer such as a plastic film or paper surface-treated with a release agent such as silicone-based, long-chain alkyl-based, fluorine-based or molybdenum sulfide; Including fluorine-based polymers such as polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene/hexafluoropropylene copolymer, and chlorofluoroethylene/vinylidene fluoride copolymer Low-adhesive substrate; Low-adhesion substrates containing non-polar polymers such as olefin resins (eg, polyethylene, polypropylene, etc.); And the like.

As a method of providing the pressure-sensitive adhesive layer on the substrate, any suitable means can be adopted within a range that does not impair the effects of the present invention. As such a means, it is a method of forming a pressure-sensitive adhesive layer, preferably by applying a coating solution for forming a pressure-sensitive adhesive layer on a substrate.

In the formation of the pressure-sensitive adhesive layer by the above-described application, the unevenness of the application during the application may affect the variation in the thickness of the adhesive tape. As one of the means for reducing such an influence, the winding tension of the adhesive tape obtained after application and construction is preferably 200 N/m or less, more preferably 30 N/m to 180 N/m, and more preferably 30 N/m to 160 N/m, particularly preferably 30 N/m to 150 N/m. The winding tension refers to the tension when the adhesive tape is wound in a roll shape. By adjusting the winding tension within the above range, it is possible to reduce the influence of the unevenness of coating during application and the like on the thickness variation of the adhesive tape, and the stress of the adhesive tape of the present invention against the expansion or pin lifting of the tape It can be more uniform within the plane.

As another one of the means for reducing the influence of the unevenness of coating during coating and the like on the thickness variation of the adhesive tape, the drying temperature at the time of drying the adhesive tape obtained after coating is preferably 200°C or less, and more It is preferably 180°C or less, more preferably 160°C or less. By adjusting the drying temperature within the above range, it is possible to reduce the influence of the unevenness of coating during application and the like on the thickness variation of the adhesive tape, and the stress of the adhesive tape of the present invention against the expansion or pin lift of the tape It can be more uniform within the plane.

As the coating method, any suitable coating method can be adopted within a range that does not impair the effects of the present invention. Examples of such a coating method include a reverse method, a direct method, and various methods in which a metering roll is combined. In order to sufficiently express the effect of the present invention, it is preferable to adjust the variation in thickness of the coating layer in the wet state containing a solvent to within ±20% in the width direction.

<Non-adhesive layer>

The adhesive tape of the present invention preferably includes an adhesive layer on one side of the substrate, and a non-adhesive layer on the opposite side of the adhesive layer of the substrate.

The composition of such a non-adhesive layer is not particularly limited, and examples thereof include a silicone layer, a (meth)acrylic polymer layer, a mixed layer of a silicone layer and a (meth)acrylic polymer layer, and a silicone obtained by graft polymerization of a (meth)acrylic polymer. Layers, etc. are mentioned. Among these, a mixed layer of silicone and (meth)acrylic polymer is preferable. By using the non-adhesive layer as a mixed layer of silicone and (meth)acrylic polymer, the affinity between the non-adhesive layer and the substrate (especially plastic film) is improved, and the adhesive tape of the present invention has good followability to deformation such as stretching. do.

It is preferable that the surface of the non-adhesive layer has an uneven structure. When the surface of the non-adhesive layer has an uneven structure, excessive adhesion to the pedestal can be effectively suppressed. Specifically, in this uneven structure, the arithmetic mean surface roughness Ra of the non-adhesive layer is preferably 0.1 μm or more, more preferably 0.1 μm to 3.0 μm, further preferably 0.2 μm to 2.0 μm, It is particularly preferably 0.3 µm to 2.0 µm, and most preferably 0.5 µm to 2.0 µm. When the arithmetic mean surface roughness Ra of the non-adhesive layer falls within the above range, it is possible to suppress occurrence of excessive adhesion when adsorption and fixation by negative pressure is performed. In addition, the method of measuring the arithmetic mean surface roughness Ra of the non-adhesive layer will be described later.

In the non-adhesive layer, the glass transition temperature Tg by differential scanning calorimetry (DSC measurement) is preferably 20° C. or higher, more preferably 30° C. or higher, still more preferably 50° C. or higher, particularly preferably Is above 55°C. The upper limit of the glass transition temperature Tg by differential scanning calorimetry of the non-adhesive layer is not particularly limited, but from the viewpoint of handling properties, etc., it is preferably 200°C or less, more preferably 170°C or less, and further preferably Is 150°C or less, particularly preferably 130°C or less, and most preferably 100°C or less. When the glass transition temperature Tg by differential scanning calorimetry of the non-adhesive layer is within the above range, the hardness of the surface of the non-adhesive layer is appropriately increased even under high temperature, thus increasing heat resistance, and the adhesive tape of the present invention is fixed by negative pressure. In the case of performing dicing or the like by performing adsorption and fixing on the pedestal, it is possible to effectively suppress the occurrence of excessive adhesion due to heat generation of the pedestal. In addition, a method of measuring the glass transition temperature Tg by differential scanning calorimetry (DSC measurement) of the non-adhesive layer will be described later.

When the non-adhesive layer contains a (meth)acrylic polymer, the (meth)acrylic polymer in the non-adhesive layer has an SP value of preferably 9.0 (cal/cm 3) ^0.5 to 12.0 (cal/cm 3) ^0.5 , More preferably, it is 9.5 (cal/cm 3) ^0.5 to 11.5 (cal/cm 3) ^0.5 , and still more preferably 9.5 (cal/cm 3) ^0.5 to 11.0 (cal/cm 3) ^0.5 . The SP value is a solubility parameter calculated by the Small equation. The calculation of the SP value can be performed by a method described in a known document (for example, Journal of Applied Chemistry, 3, 71, 1953., etc.).

The non-adhesive layer preferably has a phase separation structure. Since the non-adhesive layer has a phase-separated structure, a minute uneven structure can be efficiently formed on the surface of the non-adhesive layer. This is presumably, for example, in the case where the non-adhesive layer is a mixed layer of silicone and (meth)acrylic polymer, for example, it is assumed that irregularities are generated depending on the difference in the material mobility of silicone and (meth)acrylic polymer when the phase separation structure is created. do. By forming this uneven structure, in the adhesive tape of the present invention, in the case of performing adsorption and fixation by negative pressure, it is possible to suppress the occurrence of over-adhesion, and effectively suppress blocking in the form of a roll shape. In addition, it is possible to suppress bursting or tearing when rewinding from a roll-shaped form.

The non-adhesive layer preferably includes a silicone-rich phase containing more silicone than the (meth)acrylic polymer and a (meth)acrylic polymer-rich phase containing more (meth)acrylic polymer than silicone. The non-adhesive layer, more specifically, preferably includes the silicone-rich phase and the (meth)acrylic polymer-rich phase in a phase-separated structure independent from each other, and more preferably, the silicone-rich phase is at the air interface side (substrate (especially , Plastic film), and the (meth)acrylic polymer rich phase is present on the substrate (especially, the plastic film) side. By having such a phase-separated structure, blocking is effectively suppressed by the silicone-rich phase present on the air interface side, and the non-adhesive layer and the substrate (with the (meth)acrylic polymer-rich phase present on the substrate (especially plastic film)) In particular, the affinity of the plastic film) improves, and the deformation followability becomes good. This phase-separated structure can be formed by adjusting the mixing ratio of the silicone and the (meth)acrylic polymer in the non-adhesive layer as follows.

The non-adhesive layer has a phase-separated structure, and includes a silicone-rich phase containing more silicone than a (meth)acrylic polymer and a (meth)acrylic polymer rich phase containing more (meth)acrylic polymer than silicone, as described above. What to do can be observed by any suitable method. As such an observation method, for example, using an electron microscope such as a transmission electron microscope (TEM), a scanning electron microscope (SEM), and an electrolytic emission scanning electron microscope (FE-SEM), the cross section of the non-adhesive layer is observed in shape. There is a method. The two-layer separation structure can be read by shading on the shape observation. Further, a method of observing by observing a change in the content of silicon or carbon contained in the composition while changing the depth of the probe light from the air interface side to the interior of the non-adhesive layer by infrared absorption spectroscopy by the total reflection method is also mentioned. In addition, a method of observing by an X-ray microanalyzer or X-ray photoelectron spectroscopy is also mentioned. Moreover, you may observe by combining these methods suitably.

When the non-adhesive layer has a phase-separated structure of a silicone-rich phase present on the air interface side (a side opposite to the substrate (especially plastic film)) and a (meth)acrylic polymer-rich phase present on the substrate (especially plastic film) side, the above When the non-adhesive layer is adsorbed and fixed to the fixing base by negative pressure and the fixing base is heated when dicing, etc., the surface structure of the phase-separated structure is destroyed by the heat load caused by the heat generation, and in particular, the heat generated is fixed. The surface structure of the phase-separated structure in the convex portion that is in frequent contact with the dragon pedestal may be destroyed, and the (meth)acrylic polymer rich phase may be exposed to the air interface side in the convex portion. However, in the adhesive tape of the present invention, since the glass transition temperature Tg by differential scanning calorimetry of the non-adhesive layer is preferably within the above range, the hardness of the convex portion subjected to the heat load is appropriately high, and thus the heat resistance is increased. . For this reason, when dicing or the like by adsorbing and fixing the adhesive tape of the present invention to a fixing pedestal under negative pressure, it is possible to effectively suppress the occurrence of excessive adhesion due to heat generation of the pedestal.

When the non-adhesive layer is a mixed layer of silicone and (meth)acrylic polymer, the mixing ratio of silicone and (meth)acrylic polymer in the non-adhesive layer is by weight, preferably silicone:(meth)acrylic polymer = 1:50 to 50 :1, more preferably, silicone:(meth)acrylic polymer = 1:30 to 30:1, more preferably, silicone:(meth)acrylic polymer =1:10 to 10:1, particularly preferably Specifically, silicone: (meth)acrylic polymer = 1:5 to 5:1, and most preferably, silicone: (meth)acrylic polymer = 1:3 to 5:1. If the content ratio of silicone in the non-adhesive layer is too large, the chemical affinity with the back surface of the base material (especially plastic film) decreases, and there is a fear that it is difficult to become familiar with the back surface of the base material (particularly, the plastic film). In addition, if the content ratio of silicone in the non-adhesive layer is too large, when the adhesive tape is used, the followability to deformation such as stretching is deteriorated, and the non-adhesive layer is crushed to cause contamination. If the content ratio of the (meth)acrylic polymer in the non-adhesive layer is too large, there is a fear that the non-adhesive layer may act as an acrylic pressure-sensitive adhesive, and blocking is likely to occur.

As the silicone, any suitable silicone can be adopted. Examples of such silicones include addition-type silicones obtained by forming a releasable film by curing alkenyl group-containing polydialkylsiloxanes and polydialkylhydrogenpolysiloxanes by addition reaction using platinum-based compounds as catalysts, and methyl using tin-based catalysts. Condensation type silicone etc. obtained by making an ol group-containing polydialkylsiloxane and a polydialkylhydrogen polysiloxane react are mentioned. As an example of the addition type silicone, "KS-776A" and "KS-839L" manufactured by Shin-Etsu Silicon are mentioned, for example. As an example of the condensed silicone, "KS723A/B" manufactured by Shin-Etsu Silicon, etc. are mentioned, for example. Further, when producing silicone, in addition to a platinum-based catalyst or a tin-based catalyst, other crosslinking agents, crosslinking accelerators, and the like may be appropriately used. In addition, silicone properties are classified into a type dissolved in an organic solvent such as toluene, an emulsion type obtained by emulsifying them, and a non-solvent type containing only silicone. In addition, in addition to addition-type silicone and condensation-type silicone, silicone/acrylic graft polymer, silicone/acrylic block polymer, and the like can be used. Examples of the silicone/acrylic graft polymer include Cymac GS-30, GS101, US-270, US-350, and US-380 (above, manufactured by Toagose Co., Ltd.). Examples of the silicone/acrylic block polymer include Modifier FS700, FS710, FS720, FS730, FS770 (above, manufactured by Nichiyu Co., Ltd.).

As the (meth)acrylic polymer, any suitable (meth)acrylic polymer can be employed. In the present invention, "(meth)acryl" means "acrylic and/or methacrylic".

The (meth)acrylic polymer is a polymer composed of a monomer component containing a (meth)acrylic monomer as a main monomer. The content ratio of the (meth)acrylic monomer in the monomer component constituting the (meth)acrylic polymer is preferably 50% by weight or more, more preferably 70% by weight to 100% by weight, still more preferably 90% by weight to 100% by weight. % By weight, particularly preferably 95% to 100% by weight. Among the monomer components, the number of monomers may be only one or two or more.

As a (meth)acrylic monomer, Preferably, (meth)acrylic acid ester and (meth)acrylic acid are mentioned.

As (meth)acrylic acid ester, a (meth)acrylic acid alkyl ester of an alkyl group (including a cycloalkyl group) having 1 to 30 carbon atoms, a hydroxyl group-containing (meth)acrylic acid ester, etc. are mentioned, for example. The number of (meth)acrylic acid esters may be one, or two or more.

Examples of the (meth)acrylate alkyl ester of an alkyl group having 1 to 30 carbon atoms (including a cycloalkyl group) include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, Butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, (meth) Cyclohexyl acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isoctyl (meth)acrylate, nonyl (meth)acrylate, isonyl (meth)acrylate, and (meth)acrylic acid Decyl, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, octadecyl (meth)acrylate , (Meth)acrylate alkyl esters of alkyl groups (including cycloalkyl groups) having 1 to 30 carbon atoms, such as nonadecyl (meth)acrylate, ecosyl (meth)acrylate, lauryl (meth)acrylate, and the like. Among these (meth)acrylic acid esters, it is preferably a (meth)acrylic acid alkyl ester of an alkyl group having 2 to 20 carbon atoms (including a cycloalkyl group), and more preferably an alkyl group having 4 to 18 carbon atoms (including a cycloalkyl group) It is (meth)acrylic acid alkyl ester of.

As a hydroxyl group-containing (meth)acrylic acid ester, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. are mentioned, for example.

The monomer component constituting the (meth)acrylic polymer may contain at least one selected from a hydroxyl group-containing monomer and a carboxyl group-containing monomer in order to sufficiently express the effects of the present invention.

As a hydroxyl-containing monomer, allyl alcohol etc. are mentioned, for example. The number of hydroxyl-containing monomers may be one, or two or more.

As a carboxyl group-containing monomer, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, crotonic acid, maleic acid, fumaric acid, itaconic acid, etc. are mentioned, for example. The number of carboxyl group-containing monomers may be one, or two or more.

When the non-adhesive layer contains a (meth)acrylic polymer, the (meth)acrylic polymer in the non-adhesive layer preferably contains a hydroxyl group-containing (meth)acrylic acid ester in the monomer component constituting the non-adhesive layer, the hydroxyl group-containing ( Compared to the total amount of the monomer components other than the meth)acrylic acid ester, it is preferably 2% by weight to 30% by weight, more preferably 3% by weight to 25% by weight, and particularly preferably 5% by weight to 20% by weight. . When the non-adhesive layer contains a (meth)acrylic polymer, the content ratio of the hydroxyl group-containing (meth)acrylic acid ester among the monomer components constituting the (meth)acrylic polymer in the non-adhesive layer is other than the hydroxyl group-containing (meth)acrylic acid ester. Compared to the total amount of the monomer components of, within the above range, a fine uneven structure is formed more efficiently on the surface of the non-adhesive layer, and by formation of this uneven structure, in the adhesive tape of the present invention, adsorption by negative pressure In addition to the ability to further suppress the occurrence of over-adhesion when fixing is performed, blocking in the form of a roll can be suppressed more effectively, and bursting or tearing when rewinding from the form of a roll form is further suppressed. can do.

When the non-adhesive layer contains a (meth)acrylic polymer, the (meth)acrylic polymer in the non-adhesive layer is preferably in monomer components other than the hydroxyl group-containing (meth)acrylic acid ester in the monomer component constituting it, ( It may contain meth)acrylic acid and/or (meth)acrylic acid ester. In this case, the content ratio of (meth)acrylic acid and (meth)acrylic acid ester is, by weight ratio, (meth)acrylic acid:(meth)acrylic acid ester, preferably 0:100 to 20:80, more preferably 0 :100 to 10:90, more preferably 0:100 to 5:95.

When the content ratio of (meth)acrylic acid and (meth)acrylic acid ester is within the above range, a fine uneven structure is more efficiently formed on the surface of the non-adhesive layer, and by formation of this uneven structure, the adhesive tape of the present invention In the case of performing adsorption and fixation by negative pressure, the occurrence of over-adhesion can be further suppressed, and blocking in the form of a roll can be more effectively suppressed, and bursting when rewinding from the form of a roll can be prevented. It can be further suppressed from tearing.

The (meth)acrylic polymer can be produced by any suitable polymerization method.

Any suitable additive may be contained in the non-adhesive layer within a range that does not impair the effects of the present invention. Examples of such additives include catalysts, ultraviolet absorbers, fillers, anti-aging agents, tackifiers, pigments, dyes, and silane coupling agents.

The thickness of the non-adhesive layer is preferably 0.01 μm to 10 μm, more preferably 0.1 μm to 5 μm, and still more preferably 0.1 μm to 2 μm. When the thickness of the non-adhesive layer is less than 0.01 μm, blocking tends to occur. If the thickness of the non-adhesive layer is larger than 10 μm, there is a fear that the followability to deformation such as stretching may be deteriorated. If the thickness of the non-adhesive layer is less than 0.01 µm, there is a concern that the effects of the present invention may be difficult to express or difficult to manufacture.

As a method of forming a non-adhesive layer on one side of a substrate (especially a plastic film), for example, a non-adhesive layer is formed by applying and drying a material of a non-adhesive layer on one side of the substrate (especially a plastic film). There is a method. Examples of the coating method include a bar coater, a gravure coater, a spin coater, a roll coater, a knife coater, an applicator, and the like.

The adhesive tape of the present invention can be used for any suitable application. As described above, the adhesive tape of the present invention can effectively suppress the occurrence of over-adhesion due to heat generation of the pedestal, etc., in the case of performing dicing or the like by adsorbing and fixing the pedestal for fixing under negative pressure. Blocking in the form of a roll is effectively suppressed, and the non-adhesive layer has good affinity with the plastic film, without bursting or tearing when rewinding from the roll-shaped form, and good followability to deformation such as stretching. . Accordingly, it can be suitably used for semiconductor processing using a semiconductor wafer made of a weak material and capable of having a fine and fine circuit pattern as an adherend. When the adhesive tape of the present invention is used for semiconductor processing, it is possible to effectively suppress the occurrence of over-adhesion due to heat generation of the pedestal or the like when dicing by performing adsorption and fixing on a fixing pedestal under negative pressure, and thus dicing It is possible to smoothly proceed the semiconductor manufacturing process including. In addition, when the adhesive tape of the present invention is used for semiconductor processing, film deformation or accumulation of stress distortion occurring due to conventional blocking does not occur. Therefore, the adhesive tape of the present invention is accurately followed and bonded to the fine and precise circuit pattern of the semiconductor wafer. In addition, since natural release of stress distortion after bonding to the semiconductor wafer does not occur, it is possible to effectively prevent the semiconductor wafer from being crushed. In particular, since the wafer used for LEDs is made of very fragile materials such as gallium nitride, gallium arsenide, and silicon carbide, the adhesive tape of the present invention is very suitable for dicing wafers used for LEDs (LED dicing). Do.

[Example]

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples at all. Parts means parts by weight. In addition, the amount of the reagent supplied to the solution is expressed by the amount of the solid content remaining by volatilizing the solution (in terms of solid content).

<average thickness>

The thickness of 55 points in the MD direction and 55 points in the TD direction was measured at intervals of 50 mm with a 1/1000 dial gauge. If the length of the measurement in the TD direction was insufficient, the position was shifted by 50 mm in the MD direction, and then the measurement was continued to calculate a value. Thereafter, 5 points from the maximum value of the total measurement value of 110 points and 5 points from the minimum value were excluded and set to 100 points. Then, the average value was calculated using the AVERAGE function of EXCEL.

<Standard deviation of thickness fluctuation σ>

The thickness of 55 points in the MD direction and 55 points in the TD direction was measured at intervals of 50 mm with a 1/1000 dial gauge. If the length of the measurement in the TD direction was insufficient, the position was shifted by 50 mm in the MD direction, and then the measurement was continued to calculate a value. Thereafter, 5 points from the maximum value of the total measurement value of 110 points and 5 points from the minimum value were excluded and set to 100 points. Then, using EXCEL's STDEV function, the standard deviation σ of the thickness variation was calculated.

<Modulus at 100% tensile in MD direction and modulus at 100% tensile in TD direction>

According to JIS-K-7127 (1999), it measured with an Instron type tensile tester (manufactured by Shimadzu Corporation, Autograph). Specifically, a sample having a width of 20 mm x a length of 100 mm was provided at an interchuck distance of 50 mm, and then pulling was performed at a tensile speed of 0.3 m/min. Thereafter, the chart was read, and the load at 100% elongation (at 50 mm elongation) was taken as the modulus.

<Dicing conditions>

Device: Brand name "DFD-651" (manufactured by DISCO)

Blade: Brand name "27HECC" (manufactured by DISCO)

Blade rotation speed: 40000rpm

Dicing speed: 120㎜/sec

Dicing depth: 25㎛

Cut mode: down cut

Dicing Size: 3.0㎜×3.0㎜

Expand amount: 10㎜

<Expand Castle>

The adhesive tape obtained in Examples and Comparative Examples was bonded to the grinding surface of a polished 6-inch semiconductor wafer (thickness = 30 µm) by two reciprocating pressing rollers in an atmosphere at 23°C and 50% RH. Subsequently, after dicing the wafer under the above dicing conditions, expansion was performed.

After the expansion, the deviation of 20 successive chips was measured and evaluated according to the following criteria. In addition, the standard of the deviation was set to 20 center lines.

(Circle): Over 20, the deviation of 1 mm or more was 1.0 or less.

×: Over 20, with a deviation of 1 mm or more exceeding 1.0

<maximum height>

The maximum elongation was measured by an Instron type tensile tester (manufactured by Shimadzu Corporation, Autograph) according to JIS-K-7127 (1999). Specifically, after attaching a sample having a width of 20 mm x a length of 100 mm at an interchuck distance of 50 mm, tensile was performed at a tensile speed of 0.3 m/min, and the value at the time of fracture was measured.

<elastic modulus>

According to JIS-K-7127 (1999), it measured with an Instron type tensile tester (manufactured by Shimadzu Corporation, Autograph). Specifically, a sample having a width of 20 mm x a length of 100 mm was installed at a distance of 50 mm between the chucks, and then pulled at a tensile speed of 0.3 m/min to obtain an initial modulus of elasticity. The initial elastic modulus was corrected in terms of the cross-sectional area of the sample by drawing a tangent line in a region of 0 to 2% elongation at break and extending the tangent line to a value of 100% elongation in a straight line.

<Observation of non-adhesive layer>

(Observation by SEM)

After processing so that the cross section of the non-adhesive layer could be observed, morphology was observed with a transmission electron microscope (SEM).

(Observation by infrared spectral measurement (ATR-IR) by total reflection method)

Using an infrared spectral spectrum meter (manufactured by Perkinermer, Spectrum One), in order to select a total reflection measurement method and change the analysis depth of the probe light, two types of total reflection measurement prisms (ZnSe45°, Ge45°) are used, and a non-adhesive layer ATR-IR measurement was performed.

<Arithmetic mean surface roughness Ra>

Measurements were made in 3D mode with 20 times the objective lens using the confocal laser microscope "LEXT3000" manufactured by OLYMPUS. The determination of the observation range in the 3D mode was performed by setting the positions at which the CF image (confocal image) becomes dark when the lens is moved up and down to the top and bottom of the observation range, respectively.

In the image reading method in the 3D mode, image reading was performed at a pitch of 0.2 µm in the Step method.

The measurement of the arithmetic mean surface roughness Ra measured Ra at an arbitrary location by roughness analysis in the analysis mode. In addition, the value was calculated|required by the average value of n=5.

<Measurement of glass transition temperature Tg by differential scanning calorimetry (DSC measurement) of the non-adhesive layer>

The non-adhesive layer was pulled together with a feather blade, and about 3 mg was sealed in a pan for measuring solids in DSC.

The fan was put into a high-sensitivity differential scanning calorimeter Q2000 of TA Instruments, and the temperature was raised from 0°C to 200°C at a heating rate of 2°C/min.

Furthermore, it cooled under the same conditions, and it heated up further. The intersection point of the measurement curve and the straight line connecting the midpoint of the external insertion of the linear portion below the transition region of the second run and the external insertion of the linear portion above the transition region was determined, and this was taken as the glass transition temperature Tg.

[Example 1]

(materials)

A flexible polyvinyl chloride film containing 27 parts by weight of a DOP plasticizer (bis(2-ethylhexyl phthalate) and 27 parts by weight manufactured by J Plus was formed by a calendering method, based on 100 parts by weight of polyvinyl chloride with a degree of polymerization P = 1050. Specifically, film-forming) The fluctuation of the compound temperature of the final bank at the time was set to ±3%, and the temperature difference of the last three rolls was set to within ±10%, and a film was formed by an inverted L-shaped calender, the thickness of the obtained soft polyvinyl chloride film (1A). Is 70 μm, the elastic modulus (MD) measured according to JIS-K-7127 (1999) was 485 MPa, and the maximum elongation (MD) measured according to JIS-K-7127 (1999) was 300%.

(Non-adhesive layer)

Silicone resin (KS-723A, manufactured by Shin-Etsu Chemical Co., Ltd.) 60 parts by weight, silicone resin (KS-723B, manufactured by Shin-Etsu Chemical Co., Ltd.) 40 parts by weight, acrylic copolymer (methyl methacrylate (MMA))/ 50 parts by weight of butyl acrylate (BA)/hydroxyethyl acrylate (HEA) = 60/30/10), 10 parts by weight of a tin catalyst (Cat-PS3, manufactured by Shin-Etsu Chemical Co., Ltd.), mixed in a solution state Thus, a mixed solution was obtained. The mixing ratio of silicone and (meth)acrylic polymer in the mixed solution (1B) was, by weight, silicone:(meth)acrylic polymer = 2:1.

The mixed solution was applied to one side of the flexible polyvinyl chloride film 1A, and dried while maintaining the drying temperature at 160°C or lower to form a non-adhesive layer 1B having a thickness of 1.0 μm.

In addition, when the non-adhesive layer 1B is observed by SEM, as shown in Figs. 3, 4, and 5, it can be confirmed that the composition is different on the air interface side and the plastic film side due to the shade on the shape observation. In addition, a silicone rich phase containing more silicone than a (meth)acrylic polymer and a (meth)acrylic polymer rich phase containing more of a (meth)acrylic polymer than silicone, and the silicone rich phase and the (meth)acrylic polymer rich phase It was observed that the phase-separated structure was independent from each other, the silicone rich phase was present on the air interface side (the opposite side of the plastic film), and the (meth)acrylic polymer rich phase was present on the plastic film side.

In addition, infrared spectroscopy measurement (ATR-IR) by total reflection was performed on the non-adhesive layer (1B). Si-CH ₃ derived from a peak near 1725 cm ^-1 derived from a carbonyl group in the (meth)acrylic polymer phase. As a result of measuring the absorbance ratio of the peak in the vicinity of 800 cm ^-1 , it was found that the peak in the vicinity of 800 cm ^-1 was increased when the prism of Ge45° was used compared to ZnSe45°. Therefore, it was found that the silicon content was improved on the air interface side compared to the substrate side.

In addition, it was also confirmed in FT-IR that the silicon-rich phase in the non-adhesive layer 1B was present on the air interface side (the opposite side of the plastic film). The measurement by FT-IR was performed using "Spectrum One" manufactured by Perkinermer, and the air interface side was measured by the ATR method with two different types of prisms (ZnSe45°, Ge45°) in the analysis depth direction. Bar, non-pressure-sensitive adhesive layer of the (meth) for the 1720㎝ ^-1 -1730㎝ ^-1 attributable to the C = O peak derived from the acrylic polymer, of the Si-CH ₃ 800㎝ ^-1 vicinity of the peak derived from verified, thereby obtaining the chart It was confirmed that the absorbance ratio of was increased when a Ge45° prism with a shallow analysis depth direction was used. From this, it was proved that the concentration of silicon was higher on the air interface side.

Considering these observations and the principle of minimizing surface free energy, it was found that a two-layer structure having a silicon-rich phase on the air interface side was formed in the non-adhesive layer.

(Adhesive layer)

100 parts by weight of an acrylic copolymer composed of butyl acrylate (BA)/acrylonitrile (AN)/acrylic acid (AA) = 85/15/2.5 (weight ratio), a melamine-based crosslinking agent (butanol-modified melamine formaldehyde resin, ``Super Becamin J-820-60N", manufactured by Nippon Polyurethane) 10 parts by weight of a DOP plasticizer (bis (2-ethylhexyl phthalate), manufactured by J Plus) 60 parts by weight of a pressure-sensitive adhesive toluene solution was prepared.

This pressure-sensitive adhesive solution was applied on the side opposite to the non-adhesive layer 1B of the soft polyvinyl chloride film 1A, and dried while maintaining the drying temperature at 160°C or lower, and then a pressure-sensitive adhesive layer (1C) having a thickness of 10 μm. ) Was formed on the side opposite to the non-adhesive layer 1B of the flexible polyvinyl chloride film 1A.

(Adhesive tape)

In the manner described above, the laminated structure of the non-adhesive layer (1B)/soft polyvinyl chloride film (1A)/adhesive layer (1C) was constructed and wound up with a winding tension of 100 N/m to prepare an adhesive tape (1). .

The results are summarized in Table 1.

[Example 2]

Except having wound up with the winding tension 150 N/m, it carried out similarly to Example 1, and produced the adhesive tape 2.

The results are summarized in Table 1.

[Example 3]

(materials)

A flexible polyvinyl chloride film containing 27 parts by weight of a DOP plasticizer (bis (2-ethylhexyl phthalate), manufactured by J Plus) with respect to 100 parts by weight of polyvinyl chloride having a degree of polymerization P = 1050 was formed into a film by a calender method. Specifically, the fluctuation of the compound temperature of the final bank at the time of film formation was set to ±4.5%, and the temperature difference of the last three rolls was set to within ±15%, and the film was formed by an inverted L-type calender. The thickness of the obtained flexible polyvinyl chloride film (3A) is 70 μm, and the elastic modulus (MD) measured according to JIS-K-7127 (1999) is 501 MPa, measured according to JIS-K-7127 (1999). The maximum elongation (MD) was 480%.

(Non-adhesive layer)

In the same manner as in Example 1, a non-adhesive layer 3B having a thickness of 1.0 µm was formed on one side of the flexible polyvinyl chloride film 3A.

(Adhesive layer)

In the same manner as in Example 1, on the side opposite to the non-adhesive layer 3B of the soft polyvinyl chloride film 3A, a pressure-sensitive adhesive layer 3C having a thickness of 10 μm was applied to the non-adhesive layer of the soft polyvinyl chloride film 3A ( It formed on the side opposite to 3B).

(Adhesive tape)

In the manner described above, the laminated structure of the non-adhesive layer (3B)/soft polyvinyl chloride film (3A)/adhesive layer (3C) was constructed, and the adhesive tape 3 was manufactured by winding up at a winding tension of 150 N/m. .

The results are summarized in Table 1.

[Comparative Example 1]

(materials)

A flexible polyvinyl chloride film containing 27 parts by weight of a DOP plasticizer (bis (2-ethylhexyl phthalate), manufactured by J Plus) with respect to 100 parts by weight of polyvinyl chloride having a degree of polymerization P = 1050 was formed into a film by a calender method. Specifically, the fluctuation of the compound temperature of the final bank at the time of film formation was set to ±10%, and the temperature difference of the last three rolls was set to within ±20%, and the film was formed by an inverted L-type calender. The obtained soft polyvinyl chloride film (C1A) has a thickness of 80 μm, and an elastic modulus (MD) measured according to JIS-K-7127 (1999) is 450 MPa, measured according to JIS-K-7127 (1999). The maximum elongation (MD) was 530%.

(Non-adhesive layer)

In the same manner as in Example 1, a non-adhesive layer (C1B) having a thickness of 1.0 µm was formed on one side of the flexible polyvinyl chloride film (C1A). The drying temperature during formation was maintained at 170°C or less.

(Adhesive layer)

In the same manner as in Example 1, on the side opposite to the non-adhesive layer (C1B) of the flexible polyvinyl chloride film (C1A), a pressure-sensitive adhesive layer (C1C) having a thickness of 10 μm was applied to the non-adhesive layer of the flexible polyvinyl chloride film (C1A) ( C1B) and formed on the opposite side. The drying temperature during formation was maintained at 170°C or less.

(Adhesive tape)

In the manner described above, the laminated structure of the non-adhesive layer (C1B)/soft polyvinyl chloride film (C1A)/adhesive layer (C1C) was constructed, and wound up with a winding tension of 250 N/m, to prepare an adhesive tape (C1). .

The results are summarized in Table 1.

[Comparative Example 2]

(materials)

A flexible polyvinyl chloride film containing 27 parts by weight of a DOP plasticizer (bis (2-ethylhexyl phthalate), manufactured by J Plus) with respect to 100 parts by weight of polyvinyl chloride having a degree of polymerization P = 1050 was formed into a film by a calender method. Specifically, the fluctuation of the compound temperature of the final bank at the time of film formation was set to ±10%, the temperature difference of the last three rolls was set to within ±10%, and the film was formed by an inverted L-type calender. The thickness of the obtained flexible polyvinyl chloride film (C2A) is 77 μm, and the elastic modulus (MD) measured according to JIS-K-7127 (1999) is 450 MPa, measured according to JIS-K-7127 (1999). The maximum elongation (MD) was 520%.

(Non-adhesive layer)

In the same manner as in Example 1, a non-adhesive layer (C2B) having a thickness of 1.0 µm was formed on one side of the flexible polyvinyl chloride film (C2A). The drying temperature during formation was maintained at 170°C or less.

(Adhesive layer)

In the same manner as in Example 1, on the side opposite to the non-adhesive layer (C2B) of the flexible polyvinyl chloride film (C2A), a pressure-sensitive adhesive layer (C2C) having a thickness of 10 μm was applied to the non-adhesive layer of the flexible polyvinyl chloride film (C2A) ( C2B) and formed on the opposite side. The drying temperature during formation was maintained at 170°C or less.

(Adhesive tape)

In the manner described above, a laminated structure of a non-adhesive layer (C2B)/soft polyvinyl chloride film (C2A)/adhesive layer (C2C) was constructed, and wound up with a winding tension of 150 N/m, to prepare an adhesive tape (C2). .

The results are summarized in Table 1.

The pressure-sensitive adhesive tape of the present invention has a small standard deviation σ of thickness fluctuations, and the stress against expansion or pin lifting is uniform within the tape surface. Accordingly, it is possible to precisely follow the fine and precise circuit pattern of the semiconductor wafer to be bonded, and since the natural release of stress distortion after bonding to the semiconductor wafer does not occur, it is possible to effectively prevent the semiconductor wafer from being broken. . In particular, since the wafer used for the LED is made of a very fragile material such as gallium nitride, gallium arsenide, and silicon carbide, the adhesive tape of the present invention is very suitable for LED dicing and the like.

100: chip
200: dicing tape

Claims (17)

It is a method of manufacturing an adhesive tape having an adhesive layer on at least one side of a substrate,
The substrate is manufactured by calendering,
In the calender molding, the fluctuation of the compound temperature of the final bank is controlled within ±5%,
The standard deviation σ of the thickness variation of the adhesive tape is 2.0 μm or less
Method for producing an adhesive tape. The method of claim 1,
A method of manufacturing an adhesive tape having an average thickness of the adhesive tape of 20 μm to 120 μm. The method according to claim 1 or 2,
The method of manufacturing an adhesive tape in which the ratio of the modulus of the adhesive tape when 100% tensile in the MD direction and the modulus when 100% tensile in the TD direction (100% modulus in the MD direction / 100% modulus in the TD direction) is 0.5 to 1.9. The method according to claim 1 or 2,
A method for producing an adhesive tape wherein the standard deviation σ of the variation in thickness of the substrate is 2.0 µm or less. The method according to claim 1 or 2,
A method of manufacturing an adhesive tape having an average thickness of the substrate of 20 μm to 120 μm. The method according to claim 1 or 2,
A method for producing an adhesive tape having a maximum elongation of 100% or more measured according to JIS-K-7127 (1999) of the above base material. The method according to claim 1 or 2,
A method of manufacturing an adhesive tape in which the substrate is a plastic film. The method of claim 7,
The method for producing an adhesive tape, wherein the plastic film contains at least one selected from polyvinyl chloride, polyolefin, and ethylene-vinyl acetate copolymer. The method according to claim 1 or 2,
A method for producing an adhesive tape comprising the pressure-sensitive adhesive layer on one side of the substrate and a non-adhesive layer on the side opposite to the pressure-sensitive adhesive layer of the substrate. The method of claim 9,
The method of manufacturing an adhesive tape in which the non-adhesive layer is a mixed layer of silicone and a (meth)acrylic polymer. The method of claim 10,
The mixing ratio of the silicone and the (meth)acrylic polymer in the non-adhesive layer is, by weight, silicone: (meth)acrylic polymer = 1:50 to 50: 1. The method of claim 9,
A method of manufacturing an adhesive tape in which the non-adhesive layer has a phase-separated structure. The method of claim 9,
A method of manufacturing an adhesive tape having a thickness of the non-adhesive layer of 0.01 μm to 10 μm. The method according to claim 1 or 2,
A method for producing an adhesive tape in which the adhesive layer contains at least one (meth)acrylic polymer. The method according to claim 1 or 2,
A method of manufacturing an adhesive tape comprising a release liner on the surface of the adhesive layer. The method according to claim 1 or 2,
A method of manufacturing an adhesive tape used in semiconductor processing. The method according to claim 1 or 2,
A method of manufacturing an adhesive tape used for LED dicing.

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