TWI801520B - Method of using adhesive tape and method of manufacturing semiconductor device - Google Patents

Abstract

The object of the present invention is to provide an adhesive tape capable of stably holding wafers, wafers, etc. during processing of semiconductor wafers, etc.

The solution of the present invention is to provide an adhesive tape, which is an adhesive tape comprising a base material and an adhesive layer provided on one side thereof, the loss tangent of the adhesive layer at 60°C is 0.40 or less, and the adhesive tape at 60°C The shear storage modulus of the agent layer is 3.0×10 ⁴ Pa or more.

Description

Method of using adhesive tape and method of manufacturing semiconductor device

The present invention relates to an adhesive tape. More specifically, it relates to a method that can be suitably used for semiconductor wafers when semiconductor wafers are wafered and then dry-polished to manufacture semiconductor devices. Adhesive tape temporarily fixing wafers, wafers, etc., and a method of manufacturing a semiconductor device using the adhesive tape.

As miniaturization and multifunctionalization of various electronic devices progress, the semiconductor chips mounted thereon are also required to be miniaturized and thinned. In order to reduce the thickness of the wafer, the back surface of the semiconductor wafer is usually ground to adjust the thickness. In addition, there is also a technique called a pre-dicing method, which is to form a groove with a predetermined depth from the surface side of the wafer, and then grind it from the back side of the wafer, and remove the bottom of the groove by grinding. The wafer is singulated and wafers are obtained. Since the back grinding of the wafer and the singulation of the wafer can be performed simultaneously by the pre-dicing method, thin wafers can be manufactured efficiently.

Previously, when wafers were manufactured by pre-cutting during back grinding of semiconductor wafers, an adhesive tape called a back grinding sheet was usually attached to the surface of the wafer to protect the circuits on the surface of the wafer, and pre-cut Fix semiconductor wafers and semiconductor wafers.

As the back grinding sheet used in the pre-cut method, an adhesive tape including a base material and an adhesive layer provided on one side of the base material can be exemplified. As an example of such an adhesive tape, Japanese Unexamined Patent Publication No. 2015-185691 (Patent Document 1) proposes an adhesive tape for semiconductor wafer processing in which a radiation-curable adhesive layer is provided on a base film. Patent Document 1 discloses, as a substrate film, a substrate obtained by laminating two different materials selected from at least polyethylene terephthalate, polypropylene, and ethylene-vinyl acetate copolymer. Film, as a preferred specific example, discloses a base film composed of three layers of polyethylene/polyethylene terephthalate/polyethylene.

When using the above-mentioned pre-dicing method to separate wafers, when performing back grinding, in order to remove heat generated during grinding, grinding chips, etc., water is supplied to the grinding surface while grinding. Back grinding. However, in such conventional backside grinding, grinding traces remain on the backside of the wafer, and it is known that this is a factor that impairs the flexural strength of the wafer. In particular, as a result of thinning and miniaturization of wafers, wafers are easily damaged and the bending strength is lowered. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2015-185691

[Problem to be solved by the invention]

In order to remove the above-mentioned grinding traces (hereinafter referred to as "damaged parts"), it has been considered to use dry polishing (dry polishing) without using water after backside grinding using water. The damaged portion is removed, and the flexural strength of the wafer is improved. The so-called dry polishing refers to a step of polishing by grinding a polishing buff without using a slurry such as water or abrasive grains.

However, unlike the back grinding step, since water is not used during dry polishing, heat generated during grinding cannot be removed by water, causing the wafer to contain heat. The heat of the chip is transferred to the adhesive tape attached to the chip. As a result, the temperature of the adhesive tape at the time of dry polishing may become 60° C. or higher.

Since the adhesive layer of the adhesive tape is formed of a resin component, it is easy to change the physical properties due to heat. If the physical properties of the adhesive layer change, the adhesiveness between the adhesive layer and the wafer will decrease, and the holding force of the adhesive layer to each wafer will become insufficient. As a result, especially in the dry polishing step, the semiconductor wafer may be peeled off from the adhesive tape and may be scattered. Such scattering of wafers not only causes a decrease in productivity, but also causes damage to other wafers due to contact with other wafers by the scattered wafers, or damages the grinding apparatus, thereby causing poor transfer to the next step.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an adhesive tape capable of stably holding wafers, wafers, and the like during processing of semiconductor wafers and the like. In particular, the object is to provide an adhesive tape capable of stably holding a wafer even when dry polishing is performed after the so-called pre-dicing method. [Means to solve the problem]

Aspects of the present invention are: [1] An adhesive tape comprising [1] a base material and an adhesive layer provided on one side thereof, wherein the loss tangent of the adhesive layer at 60° C. is 0.40 or less, The shear storage modulus of the adhesive layer at 60°C is above 3.0×10 ⁴ Pa.

[2] The adhesive tape according to [1], wherein the back surface of the semiconductor wafer having grooves formed on the surface of the semiconductor wafer is ground, and the semiconductor wafer is separated into individual pieces by the grinding. After the semiconductor wafer is dry polished, it is attached to the surface of the semiconductor wafer for use.

[3] A method of manufacturing a semiconductor device, comprising the following steps: a step of forming a groove from the surface side of a semiconductor wafer; and a step of attaching the adhesive tape described in [1] or [2] to the surface of the semiconductor wafer ; Grinding the semiconductor wafer with the adhesive tape attached on the surface and forming the groove from the back side, and removing the bottom of the groove to make it into a plurality of wafers; After being sliced into a semiconductor wafer, dry polishing is performed; and the wafer is peeled off from the adhesive tape. [Invention effect]

The adhesive tape of the present invention can stably hold a semiconductor wafer even when the temperature of the adhesive tape rises due to heat during dry polishing. Therefore, even if a pre-dicing method including a dry polishing step is performed, semiconductor wafers can be manufactured with a high yield.

form for carrying out the invention

Hereinafter, the adhesive tape of this invention is demonstrated concretely. First, main terms used in this specification will be described.

In this specification, for example, "(meth)acrylate" is used as a term representing both "acrylate" and "methacrylate", and the same applies to other similar terms.

The adhesive tape means a laminate including a substrate and an adhesive layer provided on one side thereof, and may include other constituent layers than these. For example, a primer layer may also be formed on the surface of the substrate on the side of the adhesive layer in order to improve the adhesion between the substrate surface and the adhesive layer interface, prevent the migration of low molecular weight components, and the like. In addition, in order to protect the adhesive layer until use, a release sheet may be laminated on the surface of the adhesive layer. In addition, the substrate may be a single layer or a multilayer having functional layers such as a buffer layer. The same applies to the adhesive layer.

The so-called "surface" of a semiconductor wafer refers to the surface on which circuits are formed, and the "back surface" refers to the surface on which no circuits are formed. The so-called slicing of the semiconductor wafer refers to dividing the semiconductor wafer into individual circuits to obtain semiconductor wafers.

The so-called dry polishing means a step of polishing using a lapping wheel without using a slurry containing water, abrasive grains, and the like. In addition, in this specification, it may describe as a "dry polishing process".

As the abrasive buff used in dry polishing, various general-purpose abrasive buffs can be used, and as commercially available products, DISCO's abrasive wheels "Gettering DP", "DP08 SERIES" and the like can be used, but are not limited thereto. . The damaged portion of the wafer, that is, the grinding trace is removed by dry polishing.

The so-called pre-dicing method refers to a method of forming grooves of a predetermined depth from the surface side of the wafer, grinding from the back side of the wafer, and dividing the wafer into pieces by grinding.

The so-called back grinding tape refers to an adhesive tape used to protect the circuit surface of a semiconductor wafer during back grinding of a semiconductor wafer, and especially in this specification, it refers to an adhesive tape suitable for use in a pre-dicing method.

(1. Adhesive tape) The adhesive tape of the present invention can be used particularly suitably as the above-mentioned back grinding tape. The adhesive tape of the present invention includes a substrate and an adhesive layer provided on one side thereof. Hereinafter, the constituent elements of the adhesive tape will be described in detail.

(1.1. Adhesive layer) Hereinafter, an example of the adhesive layer used in the present invention will be described in detail in order of physical properties and composition, but these are only described to facilitate the manufacture or acquisition of the adhesive layer, and should not be interpreted in any limiting manner. .

(1.2. Physical properties of the adhesive layer) In this embodiment, the loss tangent (tanδ ₆₀ ) of the adhesive layer at 60°C is 0.40 or less, and the shear storage modulus (G' ₆₀ ) of the adhesive layer at 60°C ) is 3.0×10 ⁴ pa or more.

Loss tangent (tanδ) is defined by "loss modulus/storage modulus", which is a value measured by using a dynamic viscoelasticity measuring device and responding to stresses such as tensile stress and twisting stress applied to the object . Since the loss tangent (tanδ ₆₀ ) of the adhesive layer at 60°C is within the above-mentioned range, even when stress is applied to the adhesive layer in a processing step, especially a dry polishing step, deformation of the adhesive layer can be suppressed, and the wafer Alignment can be maintained, so there is a tendency to suppress chip flying.

Also, tanδ ₆₀ is preferably at least 0.05, more preferably at least 0.10. On the other hand, tanδ ₆₀ is preferably 0.37 or less.

Also, the shear storage modulus (G') is one of indicators of the ease of deformation (hardness) of the adhesive layer. Since the shear storage modulus (G' ₆₀ ) of the adhesive layer at 60°C is within the above-mentioned range, even if the adhesive layer is stressed during the processing step, especially the dry polishing step, the adhesion between the wafer and the adhesive layer Adhesiveness is also good, and since the holding force of the adhesive layer to the wafer can be maintained, it tends to be possible to suppress the scattering of the wafer.

Also, G' ₆₀ is preferably at least 3.5×10 ⁴ Pa, more preferably at least 3.7×10 ⁴ Pa. On the other hand, G' ₆₀ is preferably at most 5.0×10 ⁵ Pa, more preferably at most 1.0×10 ⁵ Pa.

Therefore, in this embodiment, by controlling both the loss tangent and the shear storage modulus of the adhesive layer at 60° C. within the above-mentioned ranges, even when the adhesive layer is heated during dry polishing, it is possible to Effectively suppress wafer flying.

The loss tangent and shear storage modulus of the adhesive layer may be measured by known methods. For example, the adhesive layer can be made into a sample of a predetermined size, and the modulus can be measured by applying strain to the sample with a predetermined frequency in a predetermined temperature range using a dynamic viscoelasticity measuring device, and the loss tangent and Shear storage modulus.

In addition, the above-mentioned loss tangent and shear storage modulus mean physical properties at 60° C. of an adhesive layer in an uncured state before being attached to a semiconductor wafer or a semiconductor wafer. When the adhesive layer is formed of an energy ray curable adhesive, it refers to the physical properties of the adhesive layer before energy ray hardening at 60°C.

In addition, the above-mentioned loss tangent and shear storage modulus can be changed by, for example, adjusting the composition of the adhesive composition constituting the adhesive layer.

The thickness of the adhesive layer is preferably less than 200 μm, more preferably 5-80 μm, and even more preferably 10-70 μm. When the adhesive layer is thinned in this way, the ratio of the less rigid portion can be reduced in the adhesive tape, so it is easier to further prevent chipping of the semiconductor wafer that occurs during back grinding.

(1.3. Composition of adhesive layer) As long as the adhesive layer has the above-mentioned physical properties, the composition of the adhesive layer is not particularly limited. In this embodiment, the adhesive layer is made of, for example, an acrylic adhesive, a urethane adhesive, or a rubber adhesive. An adhesive, a silicone adhesive, etc., preferably an acrylic adhesive.

Also, the adhesive layer is preferably formed of an energy ray-curable adhesive. Since the adhesive layer is formed of an energy ray-curable adhesive, the loss tangent and shear storage modulus are set in the above ranges before hardening by energy ray irradiation, and the peeling force after hardening can be easily set to 1000mN/ Below 50mm.

Hereinafter, specific examples of the adhesive will be described in detail, but these are non-limiting illustrations, and the adhesive layer in the present invention should not be construed as being limited to these.

As the energy ray-curable adhesive, for example, an energy ray-curable adhesive containing a non-energy ray-curable adhesive resin (also referred to as "adhesive resin I") and an energy ray-curable compound other than the adhesive resin can be used. Adhesive composition (hereinafter also referred to as "X-type adhesive composition"). Also, as an energy ray-curable adhesive, an energy ray-curable adhesive resin containing an unsaturated group introduced into a side chain of a non-energy ray-curable adhesive resin (hereinafter also referred to as "adhesive adhesive") can also be used. Resin II") is an adhesive composition that does not contain an energy ray-curable compound other than an adhesive resin as a main component (hereinafter also referred to as "Y-type adhesive composition").

Furthermore, as the energy ray-curable adhesive, a combination of X-type and Y-type can also be used, that is, one that contains an energy-ray-curable compound other than the adhesive resin in addition to the energy ray-curable adhesive resin II. Energy ray curable adhesive composition (hereinafter also referred to as "XY type adhesive composition").

Among them, it is preferable to use an XY-type adhesive composition. By using the XY type, it has sufficient adhesive properties before curing, and on the other hand, it is possible to sufficiently reduce the peeling force to the semiconductor wafer after curing.

However, the adhesive may be formed from a non-energy ray-curable adhesive composition that does not harden even when irradiated with energy rays. The non-energy ray-curable adhesive composition is an adhesive composition that contains at least the non-energy ray-curable adhesive resin I, and does not contain the above-mentioned energy ray-curable adhesive resin II and the energy ray-curable compound.

In addition, in the following description, "adhesive resin" is used as a term which means one or both of the above-mentioned adhesive resin I and adhesive resin II. Specific adhesive resins include, for example, acrylic resins, urethane-based resins, rubber-based resins, and silicone-based resins, with acrylic resins being preferred.

(1.3.1. Acrylic resin) Hereinafter, an acrylic adhesive using an acrylic resin as an adhesive resin will be described in more detail.

Acrylic resin can use an acrylic polymer (a). The acrylic polymer (a) is obtained by polymerizing a monomer containing at least an alkyl (meth)acrylate, and contains a structural unit derived from an alkyl (meth)acrylate. Examples of the alkyl (meth)acrylate include those having 1 to 20 carbon atoms in the alkyl group, and the alkyl group may be straight or branched. Specific examples of alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-propyl (meth)acrylate, Butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, (meth)acrylate ) decyl acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate, etc. Alkyl (meth)acrylate can be used individually or in combination of 2 or more types.

Also, from the viewpoint of improving the adhesive force of the adhesive layer, the acrylic polymer (a) preferably contains a structural unit derived from an alkyl group having a carbon number of 4 or more alkyl (meth)acrylate. As carbon number of this alkyl (meth)acrylate, Preferably it is 4-12, More preferably, it is 4-6. Also, the alkyl (meth)acrylate having an alkyl group having 4 or more carbon atoms is preferably an alkyl acrylate.

In the acrylic polymer (a), the content ratio of the alkyl (meth)acrylate having an alkyl group having 4 or more carbon atoms is relative to the total amount of monomers constituting the acrylic polymer (a) (hereinafter also referred to simply as " The total amount of monomers") is preferably 40-98% by mass, more preferably 45-95% by mass, further preferably 50-90% by mass.

The acrylic polymer (a), in addition to the structural unit derived from an alkyl (meth)acrylate having an alkyl group having 4 or more carbon atoms, contains a The carbon number of the group is the copolymer of the structural unit of (meth)acrylic acid alkyl ester of 1~3 preferably; Preferably, methyl (meth)acrylate is more preferred, and methyl methacrylate is the best. In the acrylic polymer (a), an alkyl (meth)acrylate having an alkyl group having 1 to 3 carbon atoms is preferably 1 to 30% by mass, more preferably 3 to 26% by mass, based on the total amount of monomers %, more preferably 6~22% by mass.

The acrylic polymer (a) preferably has a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from the above-mentioned alkyl (meth)acrylate. Examples of the functional group of the functional group-containing monomer include a hydroxyl group, a carboxyl group, an amino group, an epoxy group, and the like. The functional group-containing monomer can react with a crosslinking agent described later to serve as a crosslinking origin, or react with an unsaturated group-containing compound to introduce an unsaturated group into the side chain of the acrylic polymer (a).

Examples of the functional group-containing monomer include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, an epoxy group-containing monomer, and the like. These monomers can be used individually or in combination of 2 or more types. Among these, hydroxyl group-containing monomers and carboxyl group-containing monomers are preferable, and hydroxyl group-containing monomers are more preferable.

Examples of hydroxyl-containing monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, (meth) Hydroxyalkyl (meth)acrylates such as 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate; vinyl alcohol, allyl alcohol and other unsaturated alcohols.

Examples of carboxyl group-containing monomers include ethylenically unsaturated monocarboxylic acids such as (meth)acrylic acid and crotonic acid; fumaric acid, itaconic acid, maleic acid, and citraconic acid; Ethylenically unsaturated dicarboxylic acids and their anhydrides, 2-carboxyethyl methacrylate, etc.

The content ratio of the functional group monomer is preferably 1 to 35% by mass, more preferably 3 to 32% by mass, and further preferably 6 to 30% by mass based on the total amount of monomers constituting the acrylic polymer (a). %.

In addition, the acrylic polymer (a) may contain, in addition to the above, compounds derived from styrene, α-methylstyrene, vinyl toluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide, etc. The structural unit of the above-mentioned acrylic monomer copolymerized monomer.

As the above-mentioned acrylic polymer (a), non-energy ray-curable adhesive resin I (acrylic resin) can be used. In addition, as an energy ray-curable acrylic resin, a compound having a photopolymerizable unsaturated group (also called an unsaturated group-containing compound) is reacted with a functional group of the above-mentioned acrylic polymer (a). made things.

The unsaturated group-containing compound is a compound having both of a substituent capable of bonding to the functional group of the acrylic polymer (a) and a photopolymerizable unsaturated group. Examples of the photopolymerizable unsaturated group include a (meth)acryl group, a vinyl group, an allyl group, and a vinylbenzyl group, and a (meth)acryl group is preferred.

Moreover, an isocyanate group, a glycidyl group, etc. are mentioned as a substituent which the compound containing an unsaturated group can bond with a functional group. Therefore, examples of the unsaturated group-containing compound include (meth)acryloxyethyl isocyanate, (meth)acryl isocyanate, glycidyl (meth)acrylate, and the like.

In addition, it is preferable to react the unsaturated group-containing compound with a part of the functional group of the acrylic polymer (a). Specifically, it is preferable to react the unsaturated group-containing compound with the acrylic polymer (a). 50-98 mol% of the functional groups it has reacts, more preferably 55-93 mol% reacts. In this way, in the energy ray-curable acrylic resin, since some functional groups remain without reacting with the unsaturated group-containing compound, crosslinking by the crosslinking agent is easy.

Moreover, the weight average molecular weight (Mw) of an acrylic resin becomes like this. Preferably it is 300,000-1.6 million, More preferably, it is 400,000-1.4 million, More preferably, it is 500,000-1.2 million.

(1.3.2. Energy ray hardening compound) The energy ray-curable compound contained in the X-type or XY-type adhesive composition is preferably a monomer or oligomer having an unsaturated group in the molecule and capable of being polymerized and hardened by energy ray irradiation.

As such an energy ray-curing compound, for example, trimethylolpropane tri(meth)acrylate, neopentylthritol (meth)acrylate, neopentylthritol tetra(meth)acrylate Poly(meth)acrylic acid such as dipentylthritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol (meth)acrylate, etc. Oligomers of ester monomers, urethane (meth)acrylates, polyester (meth)acrylates, polyether (meth)acrylates, epoxy (meth)acrylates, etc.

Among them, urethane (meth)acrylate oligomers are preferable from the viewpoint of high molecular weight and less likely to lower the modulus of the adhesive layer. The molecular weight of the energy ray-curable compound (weight average molecular weight in the case of an oligomer) is preferably 100 to 12,000, more preferably 200 to 10,000, further preferably 400 to 8,000, and most preferably 600 to 6,000.

The content of the energy ray-curable compound in the X-type adhesive composition is preferably 40-200 parts by mass, more preferably 50-150 parts by mass, further preferably 60-200 parts by mass relative to 100 parts by mass of the adhesive resin. 90 parts by mass.

On the other hand, the content of the energy ray-curable compound in the XY-type adhesive composition is preferably 1 to 30 parts by mass, more preferably 2 to 20 parts by mass, and still more preferably 100 parts by mass of the adhesive resin. Preferably, it is 3 to 15 parts by mass. In the XY type adhesive composition, since the adhesive resin is energy ray curable, even if the content of the energy ray curable compound is small, the release force can be sufficiently reduced after energy ray irradiation.

(1.3.3. Cross-linking agent) The adhesive composition preferably further contains a crosslinking agent. The crosslinking agent is, for example, reacting a functional group derived from a functional group monomer that the adhesive resin has to crosslink the adhesive resins. As the cross-linking agent, for example, isocyanate-based cross-linking agents such as toluene diisocyanate, hexamethylene diisocyanate, and their adducts; ethylene glycol glycidyl ether (ethylene glycol glycidyl Ether) and other epoxy-based crosslinking agents; hexa[1-(2-methyl)-aziridinyl]triphosphatriazine and other nitrogen Aziridine-based crosslinking agents; chelate-based crosslinking agents such as aluminum chelates, and the like. These crosslinking agents may be used alone or in combination of two or more.

Among them, an isocyanate-based crosslinking agent is preferable from the viewpoint of enhancing the cohesive force to enhance the adhesive force, and the viewpoint of easiness of acquisition.

From the standpoint of accelerating the crosslinking reaction, the blending amount of the crosslinking agent is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 7 parts by mass, and even more preferably 0.05 to 10 parts by mass relative to 100 parts by mass of the adhesive resin. 4 parts by mass.

(1.3.4. Photopolymerization initiator) Also, when the adhesive composition is energy ray curable, it is preferable that the adhesive composition further contains a photopolymerization initiator. By containing a photoinitiator, even the energy rays of relatively low energy, such as an ultraviolet-ray, can fully advance the hardening reaction of an adhesive composition.

(thioxanthone)化合物、過氧化物化合物、以及胺、苯醌(quinone)等的光敏化劑等，更具體而言，可舉出，例如，1-羥基環己基苯基酮、2-羥基-2-甲基-1-苯基-丙烷-1-酮、苯偶姻、苯偶姻甲醚、苯偶姻乙醚、苯偶姻異丙醚、苄基苯基硫醚(benzyl phenyl sulfide)、一硫化四甲基秋蘭姆(tetramethylthiuram monosulfide)、偶氮雙異丁腈(azobisisobutyronitrile)、聯苄(dibenzyl)、聯乙醯(diacetyl)、8-氯蒽醌(8-chloroanthraquinone)、雙(2,4,6-三甲基苯甲醯基)苯基氧化膦(bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide)等。Examples of photopolymerization initiators include benzoin compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, 9-oxo sulfur

Photosensitizers such as (thioxanthone) compounds, peroxide compounds, amines, and quinones (quinone), etc., more specifically, include, for example, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2 -Methyl-1-phenyl-propan-1-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl phenyl sulfide, a Tetramethylthiuram monosulfide, azobisisobutyronitrile, dibenzyl, diacetyl, 8-chloroanthraquinone, bis(2, 4,6-trimethylbenzoyl)phenylphosphine oxide (bis (2,4,6-trimethylbenzoyl)phenylphosphine oxide), etc.

These photoinitiators may be used alone or in combination of two or more. The blending amount of the photopolymerization initiator is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, and further preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the adhesive resin.

(1.3.5. Other additives) The adhesive composition may contain other additives within the range that does not impair the effect of the present invention. Examples of other additives include antistatic agents, antioxidants, softeners (plasticizers), fillers, antirust agents, pigments, dyes, and the like. When compounding these additives, the compounded amount of the additives is preferably 0.01 to 6 parts by mass relative to 100 parts by mass of the adhesive resin.

In addition, from the viewpoint of improving applicability to substrates, buffer layers, release sheets, etc., the adhesive composition may be further diluted with an organic solvent to obtain a solution of the adhesive composition.

Examples of organic solvents include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, n-propanol, isopropanol wait.

In addition, the organic solvents used in the synthesis of the adhesive resin may be used as they are, or the organic solvents used in the synthesis may be added so that the solution of the adhesive composition can be uniformly coated. One or more organic solvents.

(1.4. Substrate) As a base material of the adhesive tape of this embodiment, various resin films used as a base material of a back grinding tape can be used.

Hereinafter, an example of the base material that can be used in the present invention will be described in detail, but these are only described to facilitate the acquisition of the base material, and should not be interpreted in any restrictive manner.

(1.5. Physical properties of base material) The base material is not particularly limited as long as it is configured to exhibit the performance of the adhesive tape. In this embodiment, as mentioned above, the temperature of the adhesive tape may become 60 degreeC or more at the time of dry polishing.

Since the base material and the adhesive layer are formed of the same resin component, there is a possibility of deformation due to heat. During dry polishing, if the base material of the adhesive tape is deformed by heat, the fixing of the adhesive tape at the end becomes insufficient, and the wafer on the adhesive tape cannot be sufficiently held, causing the wafer to peel off and fly away. Wafer scattering not only causes a decrease in productivity, but also causes damage to the grinding device by contacting other wafers with the scattered wafers, and causes poor transfer to the next step.

Therefore, the tensile storage modulus (E' ₆₀ ) of the substrate at 60°C in this embodiment is preferably 250 MPa or more. The tensile storage modulus (E') is one of indicators of the easiness of deformation (hardness) of a base material. By having the tensile storage modulus (E' ₆₀ ) of the base material at 60°C within the above-mentioned range, it is possible to prevent the wafer from being peeled off from the adhesive tape due to thermal deformation of the base material, and it is also possible to prevent in the processing steps, especially Deformation of the substrate due to stress during dry polishing. In addition, it is possible to appropriately maintain the cushioning performance against stress during back grinding and dry polishing.

Moreover, the semiconductor wafer with the adhesive tape attached is arranged on the adsorption machine through the adhesive tape during back grinding, dry polishing, etc., and the tensile storage modulus ( _E'60 ) in the above range, the adhesion between the adhesive tape and the adsorption machine is improved, and vibration during back grinding and dry polishing can be suppressed. In addition, after back grinding and dry polishing, it is easy to peel off the adhesive tape from the adsorption machine.

E' ₆₀ is more preferably 270 MPa or more, and more preferably 300 MPa or more. On the other hand, E' ₆₀ is more preferably not more than 4000 MPa, and is still more preferably not more than 1100 MPa.

The tensile storage modulus of the substrate may be measured by a known method in the same manner as the loss tangent and shear storage modulus of the adhesive layer. For example, it is possible to make a sample of a predetermined size from a material made of the same material as the sheet or film constituting the base material, and use a dynamic viscoelasticity measuring device to apply strain to the sample at a predetermined frequency in a predetermined temperature range, thereby measuring modulus, and the tensile storage modulus was calculated from the measured modulus.

From the viewpoint of material, physical properties, thickness, etc., the tensile storage modulus E' of the substrate can be controlled by appropriately selecting the film constituting the substrate. For example, the tensile storage modulus can be controlled within a predetermined range by selecting a film having a relatively high Tg as a constituent film, performing annealing treatment at the time of film formation of a base material, or the like.

(1.6. Specific examples of substrates) Hereinafter, although the specific example of a base material is demonstrated, it should not be interpreted in any restrictive manner, since these are described only for easy acquisition of a base material.

The substrate of the present invention, for example, may also be a relatively hard resin film. In addition, the substrate of the present invention may be a laminate in which a buffer layer made of a relatively soft resin film is laminated on one or both surfaces of a relatively hard resin film.

The thickness of the substrate is not particularly limited, but is preferably 500 μm or less, more preferably 15 to 350 μm, and still more preferably 20 to 160 μm. By setting the thickness of the base material to 500 μm or less, it is easy to control the peeling force of the adhesive tape. Moreover, by setting it as 15 micrometers or more, a base material becomes easy to function as the support body of an adhesive tape.

Various resin films can be used as the material of the base material. Here, examples of substrates having a tensile storage modulus E' of 250 MPa or more include polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate. Polyester, polyamide, polycarbonate, polyacetal, modified polyphenylene ether, polyphenylene sulfide, polyphenylene sulfide, polyether ketone, biaxially stretched polypropylene, etc. resin film.

Among these resin films, it is preferable to include one or more films selected from polyester films, polyamide films, and biaxially stretched polypropylene films, more preferably polyester films, and polyethylene terephthalic acid films. Ethylene glycol films are further preferred.

In addition, the substrate may contain plasticizers, lubricants, infrared absorbers, ultraviolet absorbers, fillers, colorants, antistatic agents, antioxidants, catalysts, etc. within the range that does not impair the effects of the present invention. In addition, the base material is transparent to energy rays irradiated when the adhesive layer is cured.

Furthermore, in order to improve the adhesion with at least one of the buffer layer and the adhesive layer, at least one surface of the substrate may be subjected to an adhesive treatment such as corona treatment. Moreover, a base material may have the above-mentioned resin film, and the easy-adhesion layer (primer layer) coated on at least one surface of the resin film.

The easily-adhesive layer-forming composition for forming the easily-adhesive layer is not particularly limited, and examples thereof include polyester-based resins, urethane-based resins, polyester-urethane-based resins, acrylic resins, etc. The composition. The composition for forming an easily-adhesive layer may contain a crosslinking agent, a photopolymerization initiator, an antioxidant, a softener (plasticizer), a filler, an antirust agent, a pigment, a dye, etc. as needed.

The thickness of the easy-adhesive layer is preferably 0.01-10 μm, more preferably 0.03-5 μm. Also, the thickness of the easy-adhesive layer is relatively small compared to the thickness of the substrate, and the easy-adhesive layer is a softer material, so it has little influence on the tensile storage modulus E', even if there is an easy-adhesive layer, The tensile storage modulus E' of the base material is also substantially the same as the tensile storage modulus of the resin film.

(1.7. Buffer layer) A buffer layer may also be provided on one or both surfaces of the aforementioned substrate. The buffer layer is made of a relatively soft resin film, which can alleviate the vibration caused by the grinding of the semiconductor wafer and prevent cracks and defects in the semiconductor wafer. In addition, the semiconductor wafer attached to the adhesive tape is placed on the suction table during back grinding, and the adhesive tape is easily and properly held on the suction table by providing the buffer layer.

The thickness of the buffer layer is preferably 8-80 μm, more preferably 10-60 μm.

Buffer layer, polypropylene film, ethylene-vinyl acetate copolymer film, ionomer resin film, ethylene･(meth)acrylic acid copolymer film, ethylene･(meth)acrylate copolymer film, LDPE film, LLDPE Film is preferred. In addition, it may be a layer formed from a composition for forming a buffer layer containing an energy ray polymerizable compound. A base material having a buffer layer can be obtained by laminating the base material and the above-mentioned film.

(1.8. Peeling sheet) A release sheet may also be attached to the surface of the adhesive tape. Specifically, the release sheet is attached to the surface of the adhesive layer of the adhesive tape. When the release sheet is attached to the surface of the adhesive layer and transported, the adhesive layer can be protected during storage. The release sheet is attached to the adhesive tape in a detachable manner, and is peeled and removed from the adhesive tape before the adhesive tape is used (that is, before wafer back grinding).

The release sheet is a release sheet having at least one surface subjected to a release treatment, and specifically, a release sheet obtained by applying a release agent to the surface of a base material for a release sheet, and the like.

As the base material for the release sheet, a resin film is preferred. As the resin constituting the resin film, for example, polyethylene terephthalate resin, polybutylene terephthalate resin, polynaphthalene di Polyester resin films such as ethylene formate resins, polyolefin resins such as polypropylene resins and polyethylene resins, and the like. Examples of release agents include rubber-based elastomers such as silicone-based resins, olefin-based resins, isoprene-based resins, and butadiene-based resins, long-chain alkyl-based resins, alkyd resins, fluorine resins, etc.

The thickness of the release sheet is not particularly limited, but is preferably 10-200 μm, more preferably 20-150 μm.

(2. Manufacturing method of adhesive tape) It does not specifically limit as a manufacturing method of the adhesive tape of this invention, It can manufacture using a well-known method.

For example, an adhesive tape having a release sheet attached to the surface of the adhesive layer can be manufactured by bonding an adhesive layer provided on a release sheet to one surface of a substrate. Furthermore, a laminate of the cushion layer and the base material can be obtained by bonding the cushion layer provided on the release sheet to the base material and removing the release sheet. Furthermore, the adhesive tape provided on the release sheet can be manufactured by bonding the adhesive layer provided on the release sheet to the base material side of the laminate to manufacture the adhesive tape in which the release sheet is attached to the surface of the adhesive layer. In addition, when the buffer layer is provided on both surfaces of the base material, the adhesive layer can be formed on the buffer layer. The release sheet attached to the surface of the adhesive layer may be appropriately peeled off and removed before use of the adhesive tape.

As a method of forming the adhesive layer on the release sheet, the adhesive composition can be directly coated on the release sheet using a known coating method, and the coated film is heated and dried to evaporate the solvent to form the adhesive layer. . Examples of the coating method include spin coating, spray coating, bar coating, knife coating, roll coating, blade coating, die coating, and gravure coating. Similarly, the adhesive composition can also be directly coated on one side of the substrate or the buffer layer to form an adhesive layer.

(3. Manufacturing method of semiconductor device) The adhesive tape of the present invention can be used particularly suitably when the backside grinding of the wafer is performed by sticking to the surface of the semiconductor wafer in the pre-dicing method. As a non-limiting usage example of the adhesive tape, a method of manufacturing a semiconductor device will be described more specifically below.

Specifically, the method for manufacturing a semiconductor device includes at least the following steps 1 to 4. Step 1: a step of forming trenches from the surface side of the semiconductor wafer; Step 2: a step of attaching the above-mentioned adhesive tape to the surface of the semiconductor wafer; Step 3: Grinding the semiconductor wafer with the adhesive tape on the surface and forming the above-mentioned grooves from the back side, removing the bottom of the grooves and converting them into a plurality of wafers; and Step 4: A step of peeling off the adhesive tape from the singulated semiconductor wafer (that is, a plurality of semiconductor wafers).

Hereinafter, each step of the manufacturing method of the above-mentioned semiconductor device will be described in detail.

(3.1. Step 1) In step 1, trenches are formed from the surface side of the semiconductor wafer. The grooves formed in this step are shallower than the thickness of the semiconductor wafer. The trenches can be formed by dicing using a conventionally known wafer dicing device or the like. In addition, the semiconductor wafer is divided into a plurality of semiconductor wafers along the trench by removing the bottom of the trench in step 3 described later.

The semiconductor wafer used in this manufacturing method may be a silicon wafer, and may also be a wafer of gallium and arsenic, a glass wafer, or a sapphire wafer. The thickness of the semiconductor wafer before grinding is not particularly limited, but is usually about 500 to 1000 μm. Also, a semiconductor wafer generally has circuits formed on its surface. Forming circuits on the wafer surface can be performed using various methods including conventional methods such as an etching method, a lift-off method, and a blade method.

(3.2. Step 2) In step 2, the adhesive tape of the present invention is pasted on the surface of the semiconductor wafer formed with the groove through the adhesive layer.

The semiconductor wafer on which the adhesive tape is attached and the grooves are formed is placed on the suction machine and is sucked and held by the suction machine. At this time, the surface side of the semiconductor wafer is placed on the machine side and sucked.

(3.3. Step 3) After step 1 and step 2, the back surface of the semiconductor wafer on the suction machine is ground and the semiconductor wafer is sliced into a plurality of semiconductor wafers.

Here, since the semiconductor wafer is formed with trenches having a depth shallower than the thickness of the semiconductor wafer, the backside grinding is performed so as to thin the semiconductor wafer to at least the bottom of the trench. With this back grinding, the grooves become slits penetrating the wafer, and the semiconductor wafer is divided and individualized into individual semiconductor chips by the slits.

The shape of the singulated semiconductor wafer may be square or elongated such as a rectangle. Also, the thickness of the individualized semiconductor wafer is not particularly limited, but is preferably about 5 to 100 μm, more preferably 10 to 45 μm. Also, the size of the individualized semiconductor wafer is not particularly limited, but the wafer size is preferably less than 50 mm ² , more preferably less than 30 mm ² , and even more preferably less than 10 mm ² .

By using the adhesive tape of the present invention, even such a thin and/or small semiconductor wafer can be prevented from being chipped during back grinding (step 3) and when the adhesive tape is peeled off (step 4).

After back grinding, dry polishing is preferred before peeling off the adhesive tape. That is, it is preferable that the manufacturing method includes the step of performing dry polishing on the singulated wafers after performing step 3 and before performing step 4.

In back grinding, grinding traces remain on the back surface of the wafer, which is a major cause of damage to the flexural strength of the wafer. As a result of the thinning and miniaturization of wafers, the wafers are easily damaged and the bending strength is lowered. In order to remove the aforementioned grinding marks (damaged parts), it is preferable to remove the damaged parts and improve the flexural strength of the wafer by dry polishing without using water after the backside grinding.

However, unlike back grinding, since water is not used during dry polishing, the heat generated during grinding cannot be removed by water, causing the wafer to contain heat. The heat of the chip is transferred to the adhesive tape on which the chip is attached. As a result, during dry polishing, the temperature of the adhesive tape becomes 60° C. or higher, and the holding force of the adhesive tape to the wafer becomes insufficient, and the wafer may be peeled off and scattered. However, by using the adhesive tape of the present invention, deformation of the adhesive tape can be suppressed, and chip scattering can be reduced. Therefore, the adhesive tape of the present invention can be used particularly suitably in order to hold semiconductor wafers, wafers, etc. in a pre-dicing method including a dry polishing step.

(3.4. Step 4) Next, the adhesive tape is peeled off from the singulated semiconductor wafer (that is, a plurality of semiconductor wafers). For example, this step is performed using the following method.

First, when the adhesive layer of the adhesive tape is formed of an energy ray-curable adhesive, the energy ray is irradiated to harden the adhesive layer. Next, a pick-up tape is attached to the back side of the singulated semiconductor wafer, and the position and direction are aligned so that it can be picked up. At this time, the ring-shaped frame arranged on the outer peripheral side of the wafer is also bonded to the pick-up tape, and the outer peripheral edge portion of the pick-up tape is fixed to the ring-shaped frame. The wafer and the ring frame can be attached to the pick-up tape at the same time, or they can be attached at different time points. Next, the adhesive tape is peeled off from the plurality of semiconductor wafers fixed on the pick-up tape.

Subsequently, a plurality of semiconductor wafers on the pick-up tape are picked up and fixed on a substrate or the like to manufacture a semiconductor device.

Moreover, the pick-up tape is not specifically limited, For example, it can be comprised with the adhesive sheet provided with the base material and the adhesive agent layer provided in one surface of the base material.

Furthermore, it is also possible to use an adhesive tape instead of the pick-up tape. Adhesive tapes include a laminate of a film adhesive and a release sheet, a laminate of a dicing tape and a film adhesive, and an adhesive layer and a release sheet that have both the functions of a dicing tape and a die bonding tape. Dicing and die bonding tape, etc. In addition, before the pick-up tape is attached, a film-like adhesive may be attached to the back side of the singulated semiconductor wafer. When a film-form adhesive is used, the film-form adhesive may have the same shape as the wafer.

The case of using an adhesive tape, the case of attaching a film-like adhesive to the back side of the singulated semiconductor wafer before attaching the pick-up tape, etc. For each semiconductor wafer, the semiconductor wafer is picked up together with the adhesive layer divided into the same shape. Then, the semiconductor wafer is fixed on the upper surface of a substrate or the like through an adhesive layer to manufacture a semiconductor device. The division of the adhesive layer can be performed using a laser, expansion, or the like.

The above, with regard to the adhesive tape of the present invention, is mainly an example of using a method of singulating semiconductor wafers using a pre-dicing method. However, the adhesive tape of the present invention can also be used for normal back grinding, and also It can be used to temporarily fix the workpiece during processing of glass, ceramics, etc. Moreover, various re-peelable adhesive tapes can also be used.

Embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments at all, and various aspects can be changed within the scope of the present invention. [Example]

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited by these examples.

The measurement method and evaluation method in this example are as follows.

(Loss Tangent and Storage Modulus) A laminate was prepared in which a release sheet (manufactured by Lintec, SP-PET381031) was attached to both surfaces of an adhesive layer (thickness: 1000 μm). Next, the obtained laminate was cut into a cylinder of 8 mmФ×3 mm, and the release sheet was peeled off to obtain a sample for measuring loss tangent and storage modulus. Using a viscoelasticity measuring device (manufactured by TA Instruments: ARES), a strain at a frequency of 1 Hz is applied to the above-mentioned sample, and the storage modulus G' and loss modulus G'' at 0 to 100°C are measured, and the value in Loss tangent tanδ and storage modulus G' ₆₀ at 60°C.

(Scattering Evaluation of Wafer) The adhesive tape with release sheet obtained in Examples and Comparative Examples was installed in a tape lamination machine (manufactured by Lintec Co., Ltd., trade name "RAD-3510") while peeling off the release sheet, and attached under the following conditions A 12-inch silicon wafer (thickness 760 μm) with grooves formed on the wafer surface by pre-dicing. Roller height: 0mm Roller temperature: 23°C (room temperature) Machine temperature: 23°C (room temperature)

The obtained adhesive tape-attached silicon wafers were separated into pieces with a thickness of 30 μm and a wafer size of 1 mm square using backside grinding (pre-dicing method).

After the back grinding was completed, the ground surface was dry-polished using DPG8760 manufactured by DISCO Corporation. As a grinding wheel, "Gettering DP" manufactured by DISCO was used. Damaged parts (grinding traces) of the wafer are removed by this dry polishing.

After completion of the dry polishing, the state of the wafer held by the end of the adhesive tape was visually observed to confirm whether or not the wafer was scattered. When there was no chip scattering, it was judged as "good", and when there was chip scattering, it was judged as "defective". Also, since the wafers present in the outermost peripheral region of the silicon wafer have a different shape (usually triangular shape) from the required shape (usually square shape), the above evaluation does not take into account the shape of these wafers. fly away. In other words, the above-mentioned evaluation was performed only to evaluate the presence or absence of scattering of square wafers.

In addition, all parts by mass in the following examples and comparative examples are solid content values.

(multilayer substrate) A polyethylene terephthalate film (tensile storage modulus E': 2500 MPa) having a thickness of 50.0 µm was used as a base material. A multilayer base material in which buffer layers (LDPE, low-density polyethylene) having a thickness of 27.5 μm were provided on both surfaces of these base materials was prepared. Therefore, the composition of the multilayer substrate is as follows. Multilayer substrate: LDPE(27.5μm)/PET(50.0μm)/LDPE(27.5μm)

(Preparation of Adhesive Composition A) 45 parts by mass of 2-ethylhexyl acrylate (2EHA), 40 parts by mass of ethyl acrylate (EA), 5 parts by mass of dimethylacrylamide (DMAA) and 10 parts by mass of 4-hydroxybutyl acrylate (4HBA) 2-methacryloxyethyl isocyanate ( methacryloyloxyethyl isocyanate, MOI) to obtain an energy-ray curable acrylic resin (Mw: 600,000).

With respect to 100 parts by mass of the obtained energy ray-curable acrylic polymer, 2.79 parts by mass (solid ratio) of a toluene diisocyanate crosslinking agent (manufactured by TOSOH, product name "CORONATE L"), and a photopolymerization initiator An energy ray-curable adhesive composition A was obtained by using 1.20 parts by mass (solid ratio) of an adhesive (manufactured by Ciba Specialty Chemicals Co., Ltd., product name "IRGACURE 184").

(Preparation of Adhesive Composition B) Acrylic polymer (a) was obtained by copolymerizing 91 parts by mass of n-butyl acrylate (BA) and 9 parts by mass of acrylic acid (AA) (Mw: 800,000).

With respect to 100 parts by mass of the obtained energy ray-curable acrylic polymer, 2.00 parts by mass (solid content) of a toluene diisocyanate-based crosslinking agent (manufactured by TOSOH, product name "CORONATE L"), an epoxy-based crosslinker agent (1,3-bis(N,N-diglycidylaminomethyl)cyclohexane; 1,3-bis (N,N-diglycidylaminomethyl)cyclohexane) 1.00 parts by mass, energy ray-curing compound (Japan Synthetic Chemical Industry Co., Ltd., product name "Ultraviolet UV-3210EA") 60 parts by mass (solid content), and photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd., IRGACURE 184) 1.00 parts by mass (solid ratio), and An energy ray-curable adhesive composition B was obtained.

(Preparation of Adhesive Composition C) Acrylic polymer (a) obtained by copolymerization of 50 mass parts of butyl acrylate (BA), 25 mass parts of methyl methacrylate (MMA) and 25 mass parts of 2-hydroxyethyl acrylate (HEA), with 2-methacryloxyethyl isocyanate (MOI) was reacted in such a way that 90 mole % of the total hydroxyl groups of the acrylic polymer (a) was added to obtain an energy-ray-curable acrylic resin ( Mw: 500,000).

With respect to 100 parts by mass of the obtained energy ray-curable acrylic polymer, 6 parts by mass of urethane acrylate oligomer (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., UT-4220) as an energy ray-curable compound was mixed, Toluene diisocyanate-based crosslinking agent (manufactured by TOSOH, product name "CORONATE L") 1.00 parts by mass (solid content), and photopolymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., product name "IRGACURE 184") 1.16 parts by mass Parts (solid ratio) to obtain energy ray curable adhesive composition C.

(Preparation of Adhesive Composition D) Acrylic polymer (a) was obtained by copolymerizing 91 parts by mass of n-butyl acrylate (BA) and 9 parts by mass of acrylic acid (AA) (Mw: 800,000).

With respect to 100 parts by mass of the obtained energy ray-curable acrylic polymer, 9.00 parts by mass (solid content) of a toluene diisocyanate-based crosslinking agent (manufactured by TOSOH, product name "CORONATE L"), epoxy-based crosslinker agent (1,3-bis(N,N-diecidylaminomethyl)cyclohexane) 0.06 parts by mass (solid content), urethane acrylate oligomer ( Nippon Synthetic Chemical Industry Co., Ltd., UV-5806) 107 parts by mass (solid content), and a photopolymerization initiator (Ciba Specialty Chemical Co., Ltd., IRGACURE 184) 1.30 parts by mass (solid ratio) to obtain energy ray hardening properties Adhesive composition D.

(Preparation of Adhesive Composition E) Acrylic polymer (a) was obtained by copolymerizing 91 parts by mass of n-butyl acrylate (BA) and 9 parts by mass of acrylic acid (AA) (Mw: 800,000).

With respect to 100 parts by mass of the obtained energy ray-curable acrylic polymer, 1.00 parts by mass (solid content) of a toluene diisocyanate-based crosslinking agent (manufactured by TOSOH, product name "CORONATE L"), an energy ray-curable compound (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., Ziguang UV-3210EA) 60 parts by mass (solid content), and photopolymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., product name "IRGACURE 184") 1.00 parts by mass (solid ratio) , and an energy ray-curable adhesive composition E was obtained.

(Preparation of Adhesive Composition F) Acrylic polymer (a1) (Mw: 800,000) was obtained by copolymerizing 91 parts by mass of n-butyl acrylate (BA) and 9 parts by mass of acrylic acid (AA). Also, in the acrylic polymer (a2) obtained by copolymerizing 62 parts by mass of butyl acrylate (BA), 10 parts by mass of methyl methacrylate (MMA), and 28 parts by mass of 2-hydroxyethyl acrylate (HEA), 2-Methacryloxyethyl isocyanate (MOI) is reacted so that 80 mol% of hydroxyl groups are added to the total hydroxyl groups of the acrylic polymer (a2) to obtain an energy-ray-curable acrylic resin (a3) (Mw: 100,000). The obtained acrylic polymers a1 and a3 were mixed so as to have a mass ratio of 10:1 to obtain an energy ray-curable acrylic resin (a).

With respect to 100 parts by mass of the obtained energy ray-curable acrylic polymer, 2.79 parts by mass (solid content) of a toluene diisocyanate-based crosslinking agent (manufactured by TOSOH, product name "CORONATE L"), and a photopolymerization initiator An energy ray-curable adhesive composition F was obtained by using 1.20 parts by mass (solid ratio) of an adhesive (manufactured by Ciba Specialty Chemicals Co., Ltd., product name "IRGACURE 184").

(Preparation of Adhesive Composition G) Acrylic polymer (a) is obtained by copolymerizing 94 parts by mass of 2-ethylhexyl acrylate (2EHA) and 6 parts by mass of 2-hydroxyethyl acrylate (HEA). 2-methacryloxyethyl isocyanate (MOI) is reacted in such a way that 50 mol% of the total hydroxyl groups are present to obtain an energy-ray-curable acrylic resin (Mw: 1.17 million).

With respect to 100 parts by mass of the obtained energy ray-curable acrylic polymer, 0.35 parts by mass (solid content) of a toluene diisocyanate-based crosslinking agent (manufactured by TOSOH, product name "CORONATE L"), and a photopolymerization initiator An energy ray-curable adhesive composition G was obtained by using 0.77 parts by mass (solid ratio) of an adhesive (manufactured by Ciba Specialty Chemicals Co., Ltd., product name "IRGACURE 184").

(Example 1) On the release-treated surface of a release sheet (manufactured by Lintec Co., Ltd., trade name: SP-PET381031), the coating liquid of the energy ray-curable adhesive composition A obtained above was applied, and heat-dried at 100° C. for 1 minutes, an adhesive layer with a thickness of 40 μm was formed on the release sheet.

The formed adhesive layer was bonded to one side of the above-mentioned multilayer base material to manufacture an adhesive tape. For the obtained adhesive tape, the loss tangent tanδ ₆₀ and the shear storage modulus G' ₆₀ of the adhesive layer at 60° C. were measured, and the scattering of the wafer was evaluated. The results are shown in Table 1.

(Examples 2-4, Comparative Examples 1-4) Except having used the adhesive composition B-G shown in Table 1 as an adhesive layer, it carried out similarly to Example 1, and produced the adhesive tape. For the obtained adhesive tape, the loss tangent tanδ ₆₀ and the shear storage modulus G' ₆₀ of the adhesive layer at 60° C. were measured, and the scattering of the wafer was evaluated. The results are shown in Table 1.

表中、「aE+b」係表示、a×10^b [Table 1]

In the table, "aE+b" means, a×10 ^b

From Table 1, it can be confirmed that when the loss tangent tan δ ₆₀ and the shear storage modulus G' ₆₀ of the adhesive layer at 60°C are within the above ranges, the scattering of the wafer can be suppressed.

none.

none.

Claims (2)

A method of using an adhesive tape, which is to grind the back surface of a semiconductor wafer with grooves formed on the surface of the semiconductor wafer, and after the semiconductor wafer is separated into semiconductor wafers by the grinding, the A method of using an adhesive tape attached to the surface of a semiconductor wafer in a dry polishing step. The adhesive tape includes a base material and an adhesive layer disposed on one side thereof. Loss of the adhesive layer at 60°C The tangent is 0.40 or less, the shear storage modulus of the aforementioned adhesive layer at 60°C is 3.0×10 ⁴ Pa or greater, and the adhesive constituting the aforementioned adhesive layer contains a structural unit derived from an alkyl (meth)acrylate And an acrylic polymer derived from a structural unit of a functional group-containing monomer, a crosslinking agent, and a photopolymerization initiator. A method of manufacturing a semiconductor device, comprising the following steps: a step of forming a groove from the surface side of a semiconductor wafer; a step of attaching an adhesive tape to the surface of the semiconductor wafer; attaching the adhesive tape to the surface and forming a The semiconductor wafer of the aforementioned trench is ground from the back side, and the bottom of the aforementioned trench is removed to make it into a plurality of wafers; after the aforementioned semiconductor wafer is divided into semiconductor wafers, dry polishing is performed and the step of peeling the wafer from the aforementioned adhesive tape, wherein the aforementioned adhesive tape includes a base material and an adhesive layer disposed on one side thereof, and the loss tangent of the aforementioned adhesive layer at 60°C is 0.40 or less, and at 60°C The shear storage modulus of the aforementioned adhesive layer is 3.0×10 ⁴ Pa or more, and the adhesive constituting the aforementioned adhesive layer includes a structural unit derived from an alkyl (meth)acrylate and a monomer derived from a functional group The structural unit of the acrylic polymer, crosslinking agent, and photopolymerization initiator.