KR20210148105A - A pressure-sensitive adhesive sheet, a method for manufacturing the pressure-sensitive adhesive sheet, and a method for manufacturing a semiconductor device - Google Patents

Abstract

It is an adhesive sheet which has a base material (Y), and the adhesive layer (X1) containing the polymer of an energy-beam polymeric component, and thermally expansible particle whose expansion initiation temperature (t) is 50-110 degreeC, The adhesive layer (X1), It is related with the adhesive sheet which is a layer formed by irradiating an energy-beam to the polymeric composition containing the said energy-beam polymeric component and the said thermally expansible particle, and forming the polymer of the said energy-beam polymeric component.

Description

A pressure-sensitive adhesive sheet, a method for manufacturing the pressure-sensitive adhesive sheet, and a method for manufacturing a semiconductor device

The present invention relates to an adhesive sheet, a method for manufacturing an adhesive sheet, and a method for manufacturing a semiconductor device.

The pressure-sensitive adhesive sheet is not only used for semi-permanently fixing a member, but also a member to be processed or inspected when processing or inspecting building materials, interior materials, electronic parts, etc. It may be used as a sheet for temporarily fixing for temporary fixing. For example, in the manufacturing process of a semiconductor device, when processing a semiconductor wafer, the sheet|seat for temporarily fixing is used.

In the manufacturing process of a semiconductor device, a semiconductor wafer is processed into a semiconductor chip through the grinding process of thinning thickness by grinding, the slicing process of cutting and separating into pieces, etc. At this time, the semiconductor wafer is given a predetermined process in the state temporarily fixed to the sheet for temporarily fixing. After the semiconductor chip obtained by performing a predetermined processing is separated from the sheet for temporarily fixing, if necessary, an expand step of widening the gap between the semiconductor chips, a rearrangement step of arranging a plurality of semiconductor chips with a wider gap, a semiconductor chip After the inversion process of inverting the front and back of the , etc. are appropriately performed, it is mounted on the board|substrate. Also in each of the above steps, it is possible to use a sheet for temporarily fixing suitable for each use.

Patent Document 1 discloses a thermally expansible adhesive layer containing thermally expansible microspheres on at least one side of a substrate, and a heat-peelable adhesive sheet for temporarily fixing at the time of cutting an electronic component is disclosed. In the same document, since the heat-peelable pressure-sensitive adhesive sheet can secure a contact area of a predetermined size with respect to an adherend at the time of cutting an electronic component, adhesion defects such as chip scattering can be prevented. On the other hand, there is a description to the effect that the contact area with the adherend can be reduced and peeling can be easily performed by heating to expand the thermally expansible microspheres after use.

Japanese Patent Publication No. 3594853

By the way, when mounting a semiconductor chip on a board|substrate, the process of sticking a semiconductor chip to a board|substrate via the film adhesive which has thermosetting which is called a diamond touch film (henceforth "DAF") is adopted.

The DAF is affixed to one surface of a semiconductor wafer or a plurality of divided semiconductor chips, and is divided into a shape similar to a semiconductor chip at the same time as the semiconductor wafer is divided into pieces or after being affixed to a semiconductor chip. The semiconductor chip with DAF obtained by separating into pieces is affixed (diamond touch) to a board|substrate from the DAF side, After that, a semiconductor chip and a board|substrate are fixed by thermosetting the DAF. At this time, the DAF needs to maintain the adhesion property by pressure reduction or heating until it is affixed to the substrate.

The heat-peelable adhesive sheet disclosed by patent document 1 forms an unevenness|corrugation on the adhesive surface by expanding thermally expansible microsphere, and peels from a to-be-adhered body. Since the pressure-sensitive adhesive sheet can reduce the contact area between the pressure-sensitive adhesive layer and the semiconductor chip by the formation of irregularities, the pressure-sensitive adhesive layer is hardened by energy ray irradiation to lower the adhesive force than the sheet for temporarily fixing, which can be avoided with a small force. It has the advantage of being able to peel from a complex.

However, when a semiconductor chip with a DAF is used as an adherend of a heat-peelable pressure-sensitive adhesive sheet, due to the heating at the time of expanding the thermally expansible microspheres, the curing of the DAF proceeds before the diamond is touched, and the adhesive force of the DAF to the substrate decreases. there is a case to do Since the fall of the adhesive force of DAF causes a fall of the bonding reliability of a semiconductor chip and a board|substrate, it is desirable to be suppressed.

On the other hand, in order to suppress the progress of curing of the DAF before the die touch, if the heat-expandable microspheres of the heat-peelable adhesive sheet have a low expansion start temperature, so that they can be peeled by heating at a low temperature, the manufacturing process of the adhesive sheet In this case, problems such as unintentionally expanding thermally expansible microspheres may occur. As a result, the performance as a sheet|seat for temporarily fixing may be impaired, such as becoming easy to produce the fall of adhesive force, and air biting at the time of sticking (air entering between a to-be-adhered body and an adhesive sheet).

The present invention is made in view of the above problems, and while having sufficient adhesive force during temporary fixing, a pressure-sensitive adhesive sheet that can be peeled by heating at low temperature, a method for producing the pressure-sensitive adhesive sheet, and manufacturing a semiconductor device using the pressure-sensitive adhesive sheet The purpose is to provide a method.

The present inventors have a base material, a pressure-sensitive adhesive layer containing the polymer of the energy-beam polymerizable component and thermally expansible particles having an expansion initiation temperature within a specific range, and the pressure-sensitive adhesive layer comprises the energy-beam polymerizable component and the thermally expansible particles. By irradiating an energy-beam to the polymeric composition to contain, and by the adhesive sheet which is a layer which forms the polymer of the said energy-beam polymerizable component, it discovered that the said subject could be solved.

That is, the present invention relates to the following [1] to [15].

[1] A pressure-sensitive adhesive sheet having a base material (Y), an energy-beam polymerizable component, and a pressure-sensitive adhesive layer (X1) containing thermally expansible particles having an expansion initiation temperature (t) of 50 to 110°C,

The pressure-sensitive adhesive layer (X1) is a layer formed by irradiating an energy ray to a polymerizable composition containing the energy ray polymerizable component and the thermally expansible particles to form a polymer of the energy ray polymerizable component.

[2] The pressure-sensitive adhesive sheet according to [1], wherein the content of the thermally expansible particles is 1 to 30 mass% with respect to the total mass (100 mass%) of the pressure-sensitive adhesive layer (X1).

[3] The pressure-sensitive adhesive sheet according to [1] or [2], wherein the pressure-sensitive adhesive layer (X1) has a thickness at 23°C of 5-150 µm.

[4] The pressure-sensitive adhesive sheet according to any one of [1] to [3], wherein the pressure-sensitive adhesive layer (X1) has an adhesive force at 23°C of 0.1 to 12.0 N/25 mm.

[5] The pressure-sensitive adhesive sheet according to any one of [1] to [4], wherein the thermally expansible particles have an average particle diameter at 23°C of 1 to 30 µm.

[6] The above [1] to [6] having a base material (Y), an adhesive layer (X1) provided on one face side of the base material (Y), and an adhesive layer (X2) provided on the other face side of the base material (Y) 5] The adhesive sheet as described in any one of.

[7] The pressure-sensitive adhesive sheet according to [6], wherein the pressure-sensitive adhesive layer (X2) is a pressure-sensitive adhesive layer that is cured by irradiating an energy ray to decrease adhesive strength.

[8] A method for producing the pressure-sensitive adhesive sheet according to any one of [1] to [7],

The method of forming the pressure-sensitive adhesive layer (X1) includes a step of irradiating an energy ray to a polymerizable composition containing the energy ray polymerizable component and the thermally expansible particles to form a polymer of the energy ray polymerizable component , a method for manufacturing an adhesive sheet.

[9] The method for producing the pressure-sensitive adhesive sheet according to [8], wherein the method for forming the pressure-sensitive adhesive layer (X1) includes the following steps I and II.

Step I: Step of forming a polymerizable composition layer comprising the polymerizable composition on one surface side of the base material (Y)

Process II: The process of forming the polymer of the said energy-beam polymeric component by irradiating an energy-beam to the said polymeric composition layer, and forming the adhesive layer (X1) containing the said polymer and the said thermally expansible particle.

[10] The method for producing the pressure-sensitive adhesive sheet according to [8] or [9], wherein the polymerizable composition does not contain a solvent.

[11] The method for producing an adhesive sheet according to any one of [8] to [10], which does not include a step of heating the polymerizable composition.

[12] The object to be processed is affixed to the pressure-sensitive adhesive sheet according to any one of [1] to [7],

One or more treatments selected from grinding treatment and slicing treatment are performed on the object to be processed;

After performing the said process, the manufacturing method of a semiconductor device including the process of heating the said adhesive sheet to the said expansion start temperature (t) or more and 120 degrees C or less to expand the adhesive layer (X1).

[13] A method for manufacturing a semiconductor device comprising the following steps 1A to 5A.

Step 1A: Step of affixing the object to be processed to the pressure-sensitive adhesive layer (X2) of the pressure-sensitive adhesive sheet according to the above [6], and attaching the support to the pressure-sensitive adhesive layer (X1) of the pressure-sensitive adhesive sheet

Step 2A: A step of performing one or more treatments selected from grinding treatment and shredding treatment on the object to be processed

Step 3A: Step of affixing a thermosetting film having thermosetting properties on the surface of the object to be processed on the opposite side to the pressure-sensitive adhesive layer (X2)

Step 4A: A step of separating the pressure-sensitive adhesive layer (X1) from the support by heating the pressure-sensitive adhesive sheet to a temperature above the expansion start temperature (t) and below 120°C

Step 5A: Step of separating the pressure-sensitive adhesive layer (X2) and the object to be processed

[14] The pressure-sensitive adhesive layer (X2) is a pressure-sensitive adhesive layer that is cured by irradiating an energy ray to decrease the adhesive strength,

The manufacturing of the semiconductor device according to [13], wherein the step 5A is a step of curing the pressure-sensitive adhesive layer (X2) by irradiating the pressure-sensitive adhesive layer (X2) with an energy ray to separate the pressure-sensitive adhesive layer (X2) from the object to be processed. Way.

[15] A method for manufacturing a semiconductor device comprising the following steps 1B to 4B.

Step 1B: Step of affixing the object to be processed to the pressure-sensitive adhesive layer (X1) of the pressure-sensitive adhesive sheet according to the above [6], and attaching the support to the pressure-sensitive adhesive layer (X2) of the pressure-sensitive adhesive sheet

Step 2B: A step of performing one or more treatments selected from grinding treatment and shredding treatment on the object to be processed

Step 3B: Step of affixing a thermosetting film having thermosetting properties on the surface of the object to be processed on the opposite side to the pressure-sensitive adhesive layer (X1)

Step 4B: A step of separating the pressure-sensitive adhesive layer (X1) and the object to be processed by heating the pressure-sensitive adhesive sheet to a temperature above the expansion start temperature (t) and below 120°C

ADVANTAGE OF THE INVENTION According to this invention, while having sufficient adhesive force at the time of temporary fixing, the adhesive sheet which can heat-peel at low temperature, the manufacturing method of the said adhesive sheet, and the manufacturing method of a semiconductor device using the said adhesive sheet can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows an example of the structure of the adhesive sheet of this invention.
It is sectional drawing which shows an example of the structure of the adhesive sheet of this invention.
It is sectional drawing explaining an example of the process of the manufacturing method of the semiconductor device of this invention.
It is sectional drawing explaining an example of the process of the manufacturing method of the semiconductor device of this invention.
It is sectional drawing explaining an example of the process of the manufacturing method of the semiconductor device of this invention.
6 is a cross-sectional view for explaining an example of the steps of the method for manufacturing a semiconductor device of the present invention.
7 is a cross-sectional view for explaining an example of the steps of the method for manufacturing a semiconductor device of the present invention.
It is sectional drawing explaining an example of the process of the manufacturing method of the semiconductor device of this invention.
It is sectional drawing explaining an example of the process of the manufacturing method of the semiconductor device of this invention.

In this specification, an "active ingredient" refers to the component except a dilution solvent among the components contained in the composition used as object.

In addition, in this specification, the mass average molecular weight (Mw) is a standard polystyrene conversion value measured by the gel permeation chromatography (GPC) method, It is a value specifically measured based on the method described in the Example.

In this specification, for example, "(meth)acrylic acid" represents both "acrylic acid" and "methacrylic acid", and other similar terms are also the same.

In addition, in this specification, with respect to a preferable numerical range (for example, the range of content, etc.), the lower limit and upper limit described in stages can be combined independently, respectively. For example, from a description such as "preferably 10 to 90, more preferably 30 to 60", "preferable lower limit (10)" and "more preferable upper limit (60)" are combined to "10 to 60" can also be done with

In this specification, an "energy beam" means having an energy proton in an electromagnetic wave or a charged particle beam, and an ultraviolet-ray, a radiation, an electron beam, etc. are mentioned as the example. Ultraviolet rays can be irradiated by using an electrodeless lamp, a high pressure mercury lamp, a metal halide lamp, UV-LED etc. as an ultraviolet source, for example. The electron beam can irradiate what was generated by an electron beam accelerator etc.

In this specification, "energy-beam polymerizability" means the property of superposing|polymerizing by irradiating an energy-beam.

In this specification, whether a "layer" is a "non-thermal expansible layer" or a "thermal expansible layer" is judged as follows.

When the layer to be judged contains thermally expansible particles, the layer is heat-treated for 3 minutes at the expansion start temperature t of the thermally expansive particles. When the volume change rate calculated from the following formula is less than 5%, the layer is judged to be a "non-thermal expansible layer", and when it is 5% or more, the layer is judged to be a "thermal expansible layer".

-Volume change rate (%) = a (volume of the layer after heat treatment - volume of the layer before heat treatment)/volume of the layer before heat treatment x 100

In addition, the layer which does not contain thermally expansible particle|grains is called "non-thermal expansible layer."

In this specification, the "surface" of a semiconductor wafer and a semiconductor chip refers to a surface on which a circuit is formed (hereinafter also referred to as a "circuit surface"), and the "rear surface" of a semiconductor wafer and a semiconductor chip refers to a surface on which a circuit is not formed. points to

[Adhesive sheet]

The adhesive sheet of one aspect of this invention has the adhesive layer (X1) containing a base material (Y), the polymer of an energy-beam polymeric component, and thermally expansible particle whose expansion initiation temperature (t) is 50-110 degreeC A sheet, wherein the pressure-sensitive adhesive layer (X1) is a layer formed by irradiating an energy ray to a polymerizable composition containing the energy ray polymerizable component and the thermally expansible particles to form a polymer of the energy ray polymerizable component. am.

The pressure-sensitive adhesive sheet of one aspect of the present invention, by heating the thermally expansible particles contained in the pressure-sensitive adhesive layer (X1) to an expansion start temperature (t) or higher to expand, thereby forming irregularities on the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer (X1), It peels from a complex. In the pressure-sensitive adhesive sheet of one embodiment of the present invention, the contact area between the pressure-sensitive adhesive layer (X1) and the adherend can be reduced by the formation of the unevenness, so that the adhesion between the pressure-sensitive adhesive sheet and the adherend can be significantly reduced. have. Thereby, the adhesive sheet of one aspect of this invention can be peeled from a to-be-adhered body by the dead weight of an adhesive sheet or the to-be-adhered body weight, without applying a peeling force at the time of heat peeling. Specifically, for example, when heating and peeling the adhesive sheet of one aspect of the present invention from an adherend, it can be peeled by dropping the adhesive sheet from the adherend by gravity with the adhesive sheet side facing downward.

In addition, in this specification, without applying the force which peels an adhesive sheet, the state in which the adhesive sheet is peeled from a to-be-adhered body, or peeling off is called "self peeling". In addition, such a property is called "self-peelability".

As described above, since the pressure-sensitive adhesive sheet of one embodiment of the present invention reduces the contact area between the pressure-sensitive adhesive layer (X1) and the adherend at the time of peeling by heating, the pressure-sensitive adhesive layer is cured by irradiation with energy rays to increase the adhesive strength. It is excellent in self-peelability than the sheet for temporarily fixing to reduce.

Moreover, since the expansion start temperature (t) of the thermally expansible particle contained in the adhesive layer (X1) is 110 degrees C or less and low temperature, the adhesive sheet of one aspect of this invention is heat-peelable at low temperature. Therefore, when an adherend is a semiconductor chip with DAF or the like that is subject to thermal change, it is possible to suppress thermal change due to heating during thermal peeling. On the other hand, when the expansion start temperature (t) of the thermally expansible particles is 50°C or higher, it is possible to suppress expansion of the thermally expansible particles due to a temperature rise, such as when grinding the adherend.

In addition, the pressure-sensitive adhesive layer (X1) of the pressure-sensitive adhesive sheet of one embodiment of the present invention is irradiated with energy rays to a polymerizable composition containing an energy-beam polymerizable component and thermally expansible particles, and a polymer of the energy-beam polymerizable component is obtained. It is a layer formed by Since a polymerizable composition is made to have high molecular weight by subsequent energy-beam polymerization, when forming a layer, it can contain the energy-beam polymeric component of a low molecular weight. Therefore, a polymerizable composition can be adjusted to the viscosity suitable for application|coating, even if it does not use solvents, such as a diluent. As a result, when forming the pressure-sensitive adhesive layer (X1) using the polymerizable composition, heat drying for removing the solvent can be omitted, and unintended expansion of the thermally expansible particles during heat drying can be suppressed. can

Although the structure of the adhesive sheet of one aspect of this invention should just have a base material (Y) and an adhesive layer (X1), depending on a use, it may have layers other than the base material (Y) and an adhesive layer (X1).

For example, when the pressure-sensitive adhesive sheet of one embodiment of the present invention is used for processing an adherend, from the viewpoint of improving the workability of the adherend, the substrate (Y) and the pressure-sensitive adhesive layer provided on one surface side of the substrate (Y) ( It is preferable to have the structure (namely, structure of a double-sided adhesive sheet) which has X1) and the adhesive layer X2 provided in the other surface side of the base material Y. By having the said structure, a to-be-adhered body can be affixed to any one adhesive layer of adhesive layer (X1) or adhesive layer (X2), and a support body can be stuck to any other adhesive layer. By fixing the adherend to the support via the pressure-sensitive adhesive sheet, when processing is performed on the adherend, vibration of the adherend, misalignment, damage to a fragile object, etc. can be suppressed, and processing precision and processing speed can be improved. .

In addition, in the following description, unless otherwise indicated, "double-sided adhesive sheet" refers to the base material (Y), the pressure-sensitive adhesive layer (X1) provided on one surface side of the base material (Y), and the other of the base material (Y). It shall mean the adhesive sheet which has the adhesive layer (X2) provided in the surface side.

The adhesive sheet of one aspect of this invention may have a peeling material on the adhesive surface of adhesive layer (X1). Moreover, when the adhesive sheet of one aspect of this invention has the structure of a double-sided adhesive sheet, you may have a peeling material on the adhesive surface of at least any one of adhesive layer (X1) and adhesive layer (X2).

Next, the structure of the adhesive sheet of one aspect of this invention is demonstrated more concretely, referring drawings.

[Structure of the adhesive sheet]

As an adhesive sheet of one aspect of this invention, the adhesive sheet 1a which has adhesive layer X1 on the base material Y shown to Fig.1 (a) is mentioned.

On the other hand, like the adhesive sheet 1b shown in FIG.1(b), the adhesive sheet of one aspect of this invention is set as the structure which further has the release material 10 on the adhesive surface of the adhesive layer X1. do.

As an adhesive sheet of another one aspect of this invention, what has the structure of the said double-sided adhesive sheet is mentioned.

As an adhesive sheet with such a structure, for example, the double-sided adhesive sheet 2a which has the structure which pinched|interposed the base material Y shown in FIG.2(a) by the adhesive layer X1 and the adhesive layer X2. can be heard

Moreover, like the double-sided adhesive sheet 2b shown in FIG.2(b), it further has the peeling material 10a on the adhesive surface of the adhesive layer X1, and it has a peeling material on the adhesive surface of the adhesive layer X2. It is good also as a structure which has (10b) further.

On the other hand, in the double-sided adhesive sheet 2b shown in FIG.2(b), the peeling force at the time of peeling the peeling material 10a from the adhesive layer X1, and the peeling material 10b from the adhesive layer X2 When the peeling force at the time of peeling is about the same, when it is going to pull and peel both peeling materials to the outside, the phenomenon that an adhesive layer is divided with two peeling materials and is tension|tensile|stretching may arise. From the viewpoint of suppressing such a phenomenon, it is preferable to use two kinds of release materials designed to have different peeling forces from the pressure-sensitive adhesive layers to be adhered to each other as the two release materials 10a and 10b.

As an adhesive sheet of another aspect, in the double-sided adhesive sheet 2a shown to Fig.2 (a), on the adhesive surface of one of the adhesive layer (X1) and the adhesive layer (X2), the peeling process was given to both surfaces The double-sided adhesive sheet which has the structure wound in roll shape what the release material was laminated|stacked may be sufficient.

The adhesive sheet of one aspect of this invention may have another layer between the base material Y and the adhesive layer (X1), and does not need to have another layer. Moreover, when the adhesive sheet of one aspect of this invention is the said double-sided adhesive sheet, in addition to the above, you may have another layer between the base material Y and the adhesive layer (X2), and it is not necessary to have another layer.

However, it is preferable that the layer which can suppress the expansion in the said surface is laminated|stacked directly on the surface opposite to the adhesion surface of the adhesive layer (X1), and it is more preferable that the base material Y is laminated|stacked directly. do.

<Write (Y)>

As a forming material of the base material Y, resin, a metal, a paper material etc. are mentioned, for example, According to the use of the adhesive sheet of one aspect of this invention, it can select suitably.

As resin, For example, Polyolefin resin, such as polyethylene and a polypropylene; vinyl-based resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, and ethylene-vinyl alcohol copolymer; polyester-based resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polystyrene; acrylonitrile-butadiene-styrene copolymer; Cellulose triacetate; polycarbonate; urethane resins such as polyurethane and acrylic modified polyurethane; polymethylpentene; polysulfone; polyether ether ketone; polyethersulfone; polyphenylene sulfide; polyimide-based resins such as polyetherimide and polyimide; polyamide-based resin; acrylic resin; A fluorine-type resin etc. are mentioned.

As a metal, aluminum, tin, chromium, titanium etc. are mentioned, for example.

Examples of the paper material include thin leaf paper, medium paper, fine paper, impregnated paper, coated paper, art paper, sulfate paper, glassine paper, and the like.

Among these, polyester-type resins, such as a polyethylene terephthalate, a polybutylene terephthalate, and a polyethylene naphthalate, are preferable.

These forming materials may be comprised by 1 type, and may use 2 or more types together.

Examples of the substrate (Y) using two or more types of forming materials in combination include those obtained by laminating a paper material with a thermoplastic resin such as polyethylene, and those in which a metal layer is formed on the surface of a resin film or sheet containing the resin.

As a formation method of a metal layer, the method of vapor-depositing metal by PVD methods, such as vacuum vapor deposition, sputtering, ion plating, and the method of sticking metal foil using a general adhesive, etc. are mentioned, for example.

From the viewpoint of improving the interlayer adhesion between the substrate (Y) and the other layer to be laminated, the surface of the substrate (Y) may be subjected to surface treatment such as oxidation method, unevenness method, etc., easy adhesion treatment, primer treatment, etc. do.

Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromic acid treatment (wet), hot air treatment, ozone irradiation treatment, and ultraviolet irradiation treatment. Moreover, as an unevenness|corrugation reducing method, the sandblasting method, the solvent treatment method, etc. are mentioned, for example.

The base material (Y) may contain a ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a slip agent, an anti-blocking agent, a coloring agent, etc. as an additive for base materials with the said resin, for example. These additives for base materials may be used independently, respectively, and may use 2 or more types together.

When the base material (Y) contains the additive for base material together with the resin, the content of each additive for base material is preferably 0.0001 to 20 parts by mass, more preferably 0.001 to 10 parts by mass relative to 100 parts by mass of the resin. is the mass part.

It is preferable that the base material (Y) is a non-thermal expansible layer.

When the substrate (Y) is a non-thermal expandable layer, the volume change (%) of the substrate (Y) calculated from the above formula is less than 5%, preferably less than 2%, more preferably less than 1%, still more preferably is less than 0.1%, even more preferably less than 0.01%.

Although the base material (Y) may contain thermally expansible particle|grains in the range which is not contrary to the objective of this invention, it is preferable not to contain thermally expansible particle|grains.

When the substrate (Y) contains thermally expansible particles, the content is preferably as small as possible, with respect to the total mass (100% by mass) of the substrate (Y), preferably less than 3% by mass, more preferably 1% by mass %, more preferably less than 0.1 mass%, still more preferably less than 0.01 mass%, still more preferably less than 0.001 mass%.

(Storage elastic modulus E' (23) at 23° C. of the substrate (Y))

The storage modulus E' (23) of the substrate (Y) at 23°C is preferably 5.0×10 ⁷ to 5.0×10 ⁹ Pa, more preferably 5.0×10 ^{8 to} 4.5×10 ⁹ Pa, still more preferably is 1.0×10 ^{9 to} 4.0×10 ⁹ Pa.

When the storage elastic modulus E' (23) of the base material (Y) is 5.0×10 ⁷ Pa or more, the expansion of the surface of the pressure-sensitive adhesive layer (X1) at the base (Y) side can be effectively suppressed, and the deformation resistance of the pressure-sensitive adhesive sheet can improve On the other hand, when the storage elastic modulus E' (23) of the base material Y is 5.0x10 ⁹ Pa or less, the handleability of an adhesive sheet can be improved.

In addition, in this specification, the storage modulus E' (23) of the base material (Y) means a value measured according to the method described in an Example.

(Storage elastic modulus E'(t) at the expansion initiation temperature (t) of the substrate (Y))

The storage elastic modulus E'(t) at the expansion start temperature (t) of the thermally expansible particles of the substrate (Y) is preferably 5.0×10 ^{6 to} 4.0×10 ⁹ Pa, more preferably 2.0×10 ^{8 to} 3.0 ×10 ⁹ Pa, more preferably 5.0 × 10 ^{8 to} 2.5 × 10 ⁹ Pa.

When the storage elastic modulus E'(t) of the base material Y is 5.0x10 ⁶ Pa or more, while being able to suppress efficiently the expansion|swelling of the surface of the base material Y side of the adhesive layer X1, the inside of an adhesive sheet Deformability can be improved. On the other hand, when the storage elastic modulus E'(t) of the base material Y is ^{4.0x10 9} Pa or less, the handleability of an adhesive sheet can be improved.

Meanwhile, in the present specification, the storage modulus E'(t) of the substrate Y means a value measured according to the method described in Examples.

(Thickness of substrate (Y))

The thickness of the base material (Y) is preferably 5 to 500 µm, more preferably 15 to 300 µm, still more preferably 20 to 200 µm. When the thickness of the base material (Y) is 5 µm or more, the deformation resistance of the pressure-sensitive adhesive sheet can be improved. On the other hand, the handleability of an adhesive sheet can be improved as the thickness of the base material Y is 500 micrometers or less.

In addition, in this specification, the thickness of the base material Y means the value measured according to the method described in an Example.

<Adhesive layer (X1)>

The adhesive layer (X1) contains the polymer of an energy-beam polymeric component, and thermally expansible particle|grains.

The polymer is, as the energy ray polymerizable component, a monomer (a1) having an energy ray polymerizable functional group (hereinafter, also referred to as “component (a1)”) and a prepolymer (a2) having an energy ray polymerizable functional group (hereinafter, It is a polymer formed by irradiating an energy ray to the polymerizable composition (henceforth "polymerizable composition (x-1)") containing "(a2) component").

In addition, in this specification, a prepolymer is a compound formed by superposing|polymerizing a monomer, Comprising: It means the compound which can comprise a polymer by superposing|polymerizing further.

(Polymerizable composition (x-1))

The energy-beam polymerizable component which polymerizable composition (x-1) contains is a component which superposes|polymerizes by irradiation of an energy-beam, and has an energy-beam polymerizable functional group.

As an energy-beam polymerizable functional group, what has carbon-carbon double bonds, such as a (meth)acryloyl group, a vinyl group, and an allyl group, is mentioned, for example. On the other hand, in the present specification, a functional group including a vinyl group or a substituted vinyl group in a part thereof, such as a (meth)acryloyl group, an allyl group, etc., and the vinyl group or the substituted vinyl group itself are collectively referred to as a "vinyl group-containing group" there is a case to do

Hereinafter, each component contained in polymerizable composition (x-1) is demonstrated.

[Monomer (a1) having an energy-beam polymerizable functional group]

The monomer (a1) having an energy-beam polymerizable functional group may be a monomer having an energy-beam polymerizable functional group, and may have, in addition to the energy-beam polymerizable functional group, a hydrocarbon group, a functional group other than the energy-beam polymerizable functional group, and the like.

(a1) As a hydrocarbon group which a component has, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, the group which combined these, etc. are mentioned, for example.

A linear or branched aliphatic hydrocarbon group may be sufficient as an aliphatic hydrocarbon group, and an alicyclic hydrocarbon group may be sufficient as it.

Examples of the linear or branched aliphatic hydrocarbon group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, sec-butyl group, n-pentyl group, n- hexyl group, 2-ethylhexyl group, n-octyl group, isooctyl group, n-decyl group, n-dodecyl group, n-myristyl group, n-palmityl group, n-stearyl group having 1 to 20 carbon atoms and an aliphatic hydrocarbon group.

As an alicyclic hydrocarbon group, a C3-C20 alicyclic hydrocarbon group, such as a cyclopentyl group, a cyclohexyl group, and isobornyl group, is mentioned, for example.

As an aromatic hydrocarbon group, a phenyl group is mentioned, for example.

Examples of the group combining an aliphatic hydrocarbon group and an aromatic hydrocarbon group include a phenoxyethyl group and a benzyl group.

Among these, (a1) component is a monomer (a1-1) having an energy-beam polymerizable functional group and a linear or branched aliphatic hydrocarbon group (hereinafter, "( It is also called a1-1) component"), it is preferable to contain the monomer (a1-2) (henceforth "(a1-2) component") etc. which have an energy-beam polymerizable functional group and an alicyclic hydrocarbon group.

When (a1) component contains (a1-1) component, the content becomes like this with respect to the total (100 mass %) of (a1) component, Preferably it is 20-80 mass %, More preferably, 40-80 mass % 70 mass %, More preferably, it is 50-60 mass %.

When (a1) component contains (a1-2) component, the content becomes like this with respect to the total (100 mass %) of (a1) component, Preferably it is 5-60 mass %, More preferably, 10 - 40 mass %, More preferably, it is 20-30 mass %.

As a monomer having an energy ray polymerizable functional group and a functional group other than the energy ray polymerizable functional group, as a functional group other than the energy ray polymerizable functional group, for example, a monomer having a hydroxyl group, a carboxy group, a thiol group, a primary or secondary amino group, etc. can be heard Among these, (a1) component is a monomer (a1-3) which has an energy-beam polymerizable functional group and a hydroxyl group from a viewpoint of more improving the formability of an adhesive layer (X1) (hereafter, "(a1-3) component") Also referred to as ) is preferred.

When (a1) component contains (a1-3) component, the content becomes like this with respect to the sum total (100 mass %) of (a1) component, Preferably it is 1-60 mass %, More preferably, 5 - 30 mass %, More preferably, it is 10-20 mass %.

(a1) The number of the energy-beam polymerizable functional groups which a component has may be one, and two or more may be sufficient as it. In addition, from the viewpoint of further improving the self-peelability of the pressure-sensitive adhesive layer (X1), the component (a1) is a monomer (a1-4) having three or more energy-beam polymerizable functional groups (hereinafter “component (a1-4)”). It is also preferable to contain ").

When (a1) component contains (a1-4) component, the content becomes like this with respect to the total (100 mass %) of (a1) component, Preferably it is 1-20 mass %, More preferably, 2 - 15 mass %, More preferably, it is 3-10 mass %.

As a monomer which has one energy-beam polymerizable functional group, the monomer (henceforth a "polymerizable vinyl monomer") which has one vinyl group containing group is preferable.

As a monomer which has two or more energy-beam polymerizable functional groups, the monomer (henceforth a "polyfunctional (meth)acrylate monomer") which has two or more (meth)acryloyl groups is preferable. When (a1) component contains the said compound, the cohesive force of the adhesive obtained by superposing|polymerizing these improves, and the adhesive layer (X1) with few to-be-adhered body contamination after peeling can be formed.

《Polymerizable Vinyl Monomer》

It will not specifically limit, if it has a vinyl group containing group as a polymerizable vinyl monomer, A conventionally well-known thing can be used suitably.

A polymerizable vinyl monomer may be used individually by 1 type, and may use 2 or more types together.

Examples of the polymerizable vinyl monomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylic Rate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, myristyl (meth) acrylate, palmityl (meth) acrylate , a compound corresponding to the component (a1-1), such as stearyl (meth) acrylate; Compounds corresponding to the component (a1-2), such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate; (meth)acrylate which does not have functional groups other than a vinyl group containing group in molecules, such as phenoxyethyl (meth)acrylate, benzyl (meth)acrylate, and polyoxyalkylene modified (meth)acrylate, etc. are mentioned. . Among these, 2-ethylhexyl acrylate and isobornyl acrylate are preferable.

The polymerizable vinyl monomer may further have a functional group other than the vinyl group-containing group in the molecule. As said functional group, a hydroxyl group, a carboxy group, a thiol group, a primary or secondary amino group, etc. are mentioned, for example. Among these, the polymerizable vinyl monomer which has a hydroxyl group corresponding to the said (a1-3) component is preferable.

As a polymerizable vinyl monomer which has a hydroxyl group, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxy hydroxyalkyl (meth)acrylates such as butyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; Hydroxyl group-containing acrylamides, such as N-methylolacrylamide and N-methylol methacrylamide, etc. are mentioned. Examples of the polymerizable vinyl monomer having a carboxyl group include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. Among these, 2-hydroxyethyl acrylate and 4-hydroxybutyl acrylate are preferable.

Moreover, as another polymerizable vinyl monomer, For example, Vinyl esters, such as vinyl acetate and a vinyl propionate; olefins such as ethylene, propylene, and isobutylene; halogenated olefins such as vinyl chloride and vinylidene chloride; styrene-based monomers such as styrene and α-methylstyrene; diene-based monomers such as butadiene, isoprene and chloroprene; nitrile-based monomers such as acrylonitrile and methacrylonitrile; Acrylamide, methacrylamide, N-methylacrylamide, N-methylmethacrylamide, N,N-dimethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, N-vinylpyrrolidone, etc. of amide-based monomers; and tertiary amino group-containing monomers such as (meth)acrylic acid N,N-diethylaminoethyl and N-(meth)acryloylmorpholine.

《Polyfunctional (meth)acrylate monomer》

As a polyfunctional (meth)acrylate monomer, if it is a monomer which has two or more (meth)acryloyl groups in 1 molecule, it will not specifically limit, A conventionally well-known thing can be used suitably.

A polyfunctional (meth)acrylate monomer may be used individually by 1 type, and may use 2 or more types together.

Examples of the polyfunctional (meth)acrylate monomer include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene Glycol di (meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone-modified dicyclopent Nyldi(meth)acrylate, ethylene oxide-modified di(meth)acrylate, di(acryloxyethyl)isocyanurate, allylated cyclohexyldi(meth)acrylate, isocyanuric acid ethylene oxide-modified diacrylate bifunctional (meth)acrylate monomers such as; Trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide modified trimethylolpropane Tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, bis (acryloxyethyl) hydroxyethyl isocyanurate, isocyanuric acid ethylene oxide modified triacrylate, ε-caprolactone modified tris ( Acryloxyethyl) isocyanurate, diglycerin tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, propionic acid-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylic polyfunctional (meth)acrylate monomers corresponding to the above components (a1-4), such as rate and caprolactone-modified dipentaerythritol hexa(meth)acrylate; and the like.

<< content of (a1) component >>

The total content of the polymerizable vinyl monomer in the polymerizable composition (x-1) is preferably 10-80 mass% with respect to the total amount (100 mass%) of the active ingredient of the polymerizable composition (x-1). , More preferably, it is 30-75 mass %, More preferably, it is 50-70 mass %.

The total content of the polyfunctional (meth)acrylate monomer in the polymerizable composition (x-1) is preferably 0.5 to 15 mass %, More preferably, it is 1-10 mass %, More preferably, it is 2-5 mass %.

The total content of the component (a1) in the polymerizable composition (x-1) is preferably 15 to 90% by mass relative to the total amount (100% by mass) of the active ingredient of the polymerizable composition (x-1); More preferably, it is 35-80 mass %, More preferably, it is 55-75 mass %.

[Prepolymer (a2) having an energy-beam polymerizable functional group]

As a prepolymer (a2) which has an energy-beam polymerizable functional group, the prepolymer which has one energy-beam polymerizable functional group, the prepolymer which has two or more energy-beam polymerizable functional groups, etc. are mentioned. Among these, component (a2) preferably contains a prepolymer having two or more energy-beam polymerizable functional groups from the viewpoint of forming an adhesive layer having excellent self-peelability and less contamination of an adherend after peeling, It is more preferable to contain the prepolymer which has two ray-polymerizable functional groups, and it is more preferable to contain the prepolymer which has two energy ray-polymerizable functional groups and has the said energy ray-polymerizable functional group at both ends.

As (a2) component, it is preferable to contain the prepolymer (henceforth "polyfunctional (meth)acrylate prepolymer") which has two or more (meth)acryloyl groups as an energy-beam polymerizable functional group. When (a2) component contains the said compound, the cohesive force of the adhesive obtained by superposing|polymerizing these improves, while being excellent in self-peelability, the adhesive layer (X1) with few to-be-adhered body contamination after peeling can be formed.

《Polyfunctional (meth)acrylate prepolymer》

As a polyfunctional (meth)acrylate prepolymer, if it is a prepolymer which has two or more (meth)acryloyl groups in 1 molecule, it will not specifically limit, A conventionally well-known thing can be used suitably.

A polyfunctional (meth)acrylate prepolymer may be used individually by 1 type, and may use 2 or more types together.

Examples of the polyfunctional (meth)acrylate prepolymer include urethane acrylate prepolymer, polyester acrylate prepolymer, epoxy acrylate prepolymer, polyether acrylate prepolymer, polybutadiene acrylate prepolymer, silicone acrylate system prepolymer, polyacrylic acrylate type prepolymer, etc. are mentioned.

The urethane acrylate-based prepolymer is, for example, a compound of polyalkylene polyol, polyether polyol, polyester polyol, hydrogenated isoprene having a hydroxyl group terminal, or hydrogenated butadiene having a hydroxyl group terminal, and polyisocyanate; It can be obtained by esterifying the polyurethane prepolymer obtained by reaction with (meth)acrylic acid or a (meth)acrylic acid derivative.

As polyalkylene polyol used for manufacture of a urethane acrylate type prepolymer, polypropylene glycol, polyethylene glycol, polybutylene glycol, polyhexylene glycol etc. are mentioned, for example, Among these, polypropylene glycol is preferable. do. On the other hand, when the number of functional groups of the obtained urethane acrylate-based prepolymer is 3 or more, for example, glycerin, trimethylolpropane, triethanolamine, pentaerythritol, ethylenediamine, diethylenetriamine, sorbitol, cross, etc. You can combine them appropriately.

As polyisocyanate used for manufacture of a urethane acrylate type prepolymer, For example, Aliphatic diisocyanate, such as hexamethylene diisocyanate and trimethylene diisocyanate; aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate and diphenyl diisocyanate; Alicyclic diisocyanate, such as dicyclohexylmethane diisocyanate and isophorone diisocyanate, etc. are mentioned, Among these, aliphatic diisocyanate is preferable and hexamethylene diisocyanate is more preferable. In addition, polyisocyanate is not limited to bifunctionality, A thing more than trifunctional can also be used.

As a (meth)acrylic acid derivative used for manufacture of a urethane acrylate type prepolymer, For example, Hydroxyalkyl (meth)acrylates, such as 2-hydroxyethyl acrylate and 4-hydroxybutyl acrylate; 2-isocyanate ethyl acrylate, 2-isocyanate ethyl methacrylate, 1, 1-bis (acryloxymethyl) ethyl isocyanate etc. are mentioned, Among these, 2-isocyanate ethyl acrylate is preferable.

As another method for producing a urethane acrylate-based prepolymer, a hydroxyl group of a compound such as polyalkylene polyol, polyether polyol, polyester polyol, hydrogenated isoprene having a hydroxyl group terminal, or hydrogenated butadiene having a hydroxyl group terminal, and isocyanate alkyl (meth) A method of reacting the -N=C=O moiety of the acrylate is exemplified. In this case, as the said isocyanate alkyl (meth)acrylate, for example, the above-mentioned 2-isocyanate ethyl acrylate, 2-isocyanate ethyl methacrylate, 1, 1-bis (acryloxymethyl) ethyl isocyanate, etc. can be used. have.

The polyester acrylate-based prepolymer can be obtained by, for example, esterifying a hydroxyl group of a polyester prepolymer having hydroxyl groups at both terminals obtained by condensation of a polyhydric carboxylic acid and a polyhydric alcohol with (meth)acrylic acid. Moreover, it can obtain also by esterifying the hydroxyl group at the terminal of the prepolymer obtained by adding alkylene oxide to polyhydric carboxylic acid with (meth)acrylic acid.

The epoxy acrylate-based prepolymer can be obtained by, for example, reacting (meth)acrylic acid with an oxylan ring such as a bisphenol-type epoxy resin or a novolak-type epoxy resin having a relatively low molecular weight to esterify it. Further, a carboxy-modified epoxy acrylate-based prepolymer in which an epoxy acrylate-based prepolymer is partially modified with a dibasic carboxylic acid anhydride may be used.

A polyether acrylate type prepolymer can be obtained by esterifying the hydroxyl group of polyether polyol with (meth)acrylic acid, for example.

The polyacrylate-based prepolymer may have an acryloyl group in a side chain, and may have an acryloyl group in both terminals or one terminal. The polyacrylate-based prepolymer having an acryloyl group in the side chain can be obtained, for example, by adding glycidyl methacrylate to the carboxy group of polyacrylic acid. In addition, the polyacrylic acrylate-based prepolymer having acryloyl groups at both ends is, for example, acrylic at both ends using the polymerization growth terminal structure of the polyacrylate prepolymer synthesized according to the ATRP (Atom 　 Transfer 　 Radical Polymerization) method. It can be obtained by introducing a royl group.

(a2) The mass average molecular weight (Mw) of component becomes like this. Preferably it is 10,000-350,000, More preferably, it is 15,000-200,000, More preferably, it is 20,000-50,000.

<< content of (a2) component >>

The total content of the polyfunctional (meth)acrylate prepolymer in the polymerizable composition (x-1) is preferably 10 to 60 mass %, More preferably, it is 15-55 mass %, More preferably, it is 20-30 mass %.

The total content of the component (a2) in the polymerizable composition (x-1) is preferably 10 to 60 mass% with respect to the total amount (100 mass%) of the active ingredient of the polymerizable composition (x-1); More preferably, it is 15-55 mass %, More preferably, it is 20-30 mass %.

The content ratio [(a2)/(a1)] of the component (a2) and the component (a1) in the polymerizable composition (x-1) is preferably 10/90 to 70/30 by mass, More preferably, it is 20/80-50/50, More preferably, it is 25/75-40/60.

It is preferable that polymerizable composition (x-1) contains a polymerizable vinyl monomer, a polyfunctional (meth)acrylate monomer, and a polyfunctional (meth)acrylate prepolymer among said energy-beam polymeric components.

The total content of the polymerizable vinyl monomer, the polyfunctional (meth)acrylate monomer, and the polyfunctional (meth)acrylate prepolymer in the energy-beam polymerizable component contained in the polymerizable composition (x-1) is energy-beam polymerization With respect to the total amount (100 mass %) of the sex component, preferably 80 mass % or more, more preferably 90 mass % or more, still more preferably 95 mass % or more, even more preferably 99 mass % or more, 100 It may be mass %.

The total content of the energy-beam polymerizable component in the polymerizable composition (x-1) is preferably 70 to 98 mass% with respect to the total amount (100 mass%) of the active ingredient of the polymerizable composition (x-1). , More preferably, it is 75-97 mass %, More preferably, it is 80-96 mass %, More preferably, it is 82-95 mass %.

[Thermal Expansive Particles]

The thermally expansible particle|grains are the particle|grains whose expansion initiation temperature (t) was adjusted to 50-110 degreeC.

The expansion start temperature (t) of the thermally expansible particles may be appropriately adjusted within the above range according to the use of the adhesive sheet, for example, when grinding an adherend, etc. From the viewpoint of suppressing the Below, more preferably, it is 100 degrees C or less, More preferably, it is 95 degrees C or less.

In addition, in this specification, the expansion start temperature (t) of thermally expansible particle|grains means the value measured based on the following method.

[Method for measuring the expansion start temperature (t) of thermally expandable particles]

To an aluminum cup having a diameter of 6.0 mm (inner diameter 5.65 mm) and a depth of 4.8 mm, 0.5 mg of thermally expansible particles to be measured are added, and a sample with an aluminum lid (5.6 mm in diameter, 0.1 mm in thickness) placed thereon is prepared.

Using a dynamic viscoelasticity measuring device, the height of the sample is measured in a state in which a force of 0.01 N is applied to the sample from the upper part of the aluminum lid by a pressurizer. Then, in a state in which a force of 0.01 N is applied by the pressurizer, it is heated from 20°C to 300°C at a temperature increase rate of 10°C/min, the displacement amount in the vertical direction of the presser is measured, and the displacement start temperature in the forward direction Let be the expansion initiation temperature (t).

The thermally expandable particle is preferably a microencapsulated foaming agent composed of an outer shell made of a thermoplastic resin and an inner shell component that is enclosed in the outer shell and vaporizes when heated to a predetermined temperature.

The thermoplastic resin constituting the outer shell of the microencapsulated foaming agent is not particularly limited, and the material and composition that can cause state changes such as melting, dissolution, and rupture at 50 to 110° C., which is the expansion start temperature (t) of thermally expandable particles, are appropriately selected. you just have to choose

Examples of the thermoplastic resin include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone. have. These thermoplastic resins may be used individually by 1 type, and may use 2 or more types together.

The encapsulation component, which is a component encapsulated in the outer shell of the microencapsulation foaming agent, may be any that expands at 50 to 110° C., which is the expansion start temperature (t) of the thermally expandable particles, for example, propane, propylene, butene, n-butane, iso and low boiling point liquids such as butane, isopentane, neopentane, n-pentane, n-hexane, isohexane, n-heptane, n-octane, cyclopropane, cyclobutane and petroleum ether.

These inclusion components may be used individually by 1 type, and may use 2 or more types together.

The expansion start temperature t of the thermally expansible particles can be adjusted by appropriately selecting the type of the encapsulation component.

The average particle diameter at 23°C before thermal expansion of the thermally expandable particles is preferably 1 to 30 µm, more preferably 4 to 25 µm, still more preferably 6 to 20 µm, still more preferably 10 to 15 µm. .

On the other hand, the average particle diameter (D ₅₀ ) of the thermally expandable particles is the volume median particle diameter (D ₅₀ ), measured using a laser diffraction particle size distribution analyzer (eg, manufactured by Malvern, product name “Master Cider 3000”). In the particle distribution of thermally expansible particles before expansion, it means a particle diameter corresponding to 50% of the cumulative volume frequency calculated from the smaller particle diameter.

_{The 90% particle diameter (D 90} ) of the thermally expandable particles at 23° C. before thermal expansion is preferably 2 to 60 µm, more preferably 8 to 50 µm, still more preferably 12 to 40 µm, still more preferably It is 20-30 μm.

On the other hand, the 90% particle diameter (D ₉₀ ) of the thermally expandable particles is the cumulative volume frequency calculated from the smaller particle diameter in the particle distribution of the thermally expandable particles before expansion measured using the laser diffraction particle size distribution measuring device. It means the particle diameter corresponded to 90%.

When the thermally expansible particles are heated to a temperature equal to or higher than the expansion initiation temperature (t), the volumetric maximum expansion rate is preferably 1.5 to 200 times, more preferably 2 to 150 times, still more preferably 2.5 to 120 times, further Preferably it is 3-100 times.

To [ content of thermally expansible particle|grains / total mass (100 mass %) of the active ingredient of polymerizable composition (x-1)) or the total mass (100 mass %) of adhesive layer (X1), Preferably 1-30 mass % , More preferably, it is 2-25 mass %, More preferably, it is 3-20 mass %.

When content of thermally expansible particle|grains is 1 mass % or more, there exists a tendency for the peelability at the time of heat peeling to improve. Moreover, while content of thermally expansible particle|grains is 30 mass % or less, while the adhesive force of an adhesive layer (X1) becomes favorable, it suppresses curling of an adhesive sheet at the time of heat peeling, and there exists a tendency which can improve handleability. .

[Other ingredients]

Polymeric composition (x-1) may contain other components other than an energy-beam polymeric component and thermally expansible particle|grains.

As said other component, the additive for adhesives used for a general adhesive other than a photoinitiator, a tackifier, and said each component, etc. are mentioned. Among these, it is preferable that polymerizable composition (x-1) contains a photoinitiator.

《Light polymerization initiator》

When polymerizable composition (x-1) contains a photoinitiator, superposition|polymerization of an energy-beam polymeric component can advance more efficiently.

Examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2 ,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl Ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 4-(2-hydroxyethoxy)phenyl-2-(hydroxy-2-propyl ) Ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-amino Anthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethyl ketal, acetophenone dimethyl ketal, p-dimethyl aminobenzoic acid ester, oligo[2-hydroxy-2-methyl-1[4-(1-methylvinyl)phenyl]propanone], 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, and the like. have. A photoinitiator may be used individually by 1 type, and may use 2 or more types together.

When polymerizable composition (x-1) contains a photoinitiator, the content is with respect to 100 mass parts of energy-beam polymeric components, Preferably it is 0.1-10 mass parts, More preferably, 0.2-5 mass parts, More preferably, it is 0.3-1 mass part.

Superposition|polymerization of an energy-beam polymeric component can be advanced more efficiently that content of a photoinitiator is 0.1 mass part or more. On the other hand, when the said content is 10 mass parts or less, it becomes possible to remove or reduce the photoinitiator which remains unreacted, and it becomes easy to adjust the adhesive layer (X1) obtained to desired physical properties.

《Tackifier》

A tackifier is a component used as needed for the purpose of improving adhesive force more.

In this specification, a "tackifier" refers to a thing with a mass average molecular weight (Mw) of less than 10,000, and is distinguished from the adhesive resin mentioned later.

The mass average molecular weight (Mw) of a tackifier is less than 10,000, Preferably it is 400-9,000, More preferably, it is 500-8,000, More preferably, it is 800-5,000.

As the tackifier, for example, C5 obtained by copolymerizing C5 fractions such as rosin-based resins, terpene-based resins, styrene-based resins, pentene produced by thermal decomposition of petroleum naphtha, isoprene, piperine, and 1,3-pentadiene. and C9 petroleum resins obtained by copolymerizing C9 fractions such as indene and vinyltoluene produced by thermal decomposition of petroleum naphtha, C9 petroleum resins, and hydrogenated resins obtained by hydrogenating them.

The softening point of a tackifier becomes like this. Preferably it is 60-170 degreeC, More preferably, it is 65-160 degreeC, More preferably, it is 70-150 degreeC.

In addition, in this specification, the "softening point" of a tackifier means the value measured based on JISK2531.

A tackifier may be used individually by 1 type, and may use together 2 or more types from which a softening point, a structure, etc. differ. When using 2 or more types of tackifiers, it is preferable that the weighted average of the softening point of these some tackifier belongs to the said range.

When polymerizable composition (x-1) contains a tackifier, the content becomes like this with respect to whole quantity (100 mass %) of the active ingredient of polymerizable composition (x-1), Preferably 0.01-65 mass %. , More preferably, it is 0.1-50 mass %, More preferably, it is 1-40 mass %, More preferably, it is 2-30 mass %.

《Additives for Adhesives》

As an additive for adhesives, a silane coupling agent, antioxidant, a softener (plasticizer), a rust preventive agent, a pigment, dye, a retarder, a reaction accelerator (catalyst), a ultraviolet absorber etc. are mentioned, for example. These additives for adhesives may be used independently, respectively, and may use 2 or more types together.

When polymerizable composition (x-1) contains the additive for adhesives, content of each additive for adhesives is with respect to 100 mass parts of energy-beam polymeric components, Preferably it is 0.0001-20 mass parts, More preferably It is 0.001-10 mass parts.

On the other hand, although polymerizable composition (x-1) may contain solvents, such as a diluent, in the range which is not contrary to the objective of this invention, it is preferable not to contain a solvent. That is, the polymerizable composition (x-1) is preferably a solvent-free polymerizable composition.

When the polymerizable composition (x-1) is a solvent-free polymerizable composition, when the pressure-sensitive adhesive layer (X1) is formed, heat drying of the solvent can be omitted, so that the expansion of the thermally expansible particles during heat drying is reduced. can be suppressed Moreover, when using a solvent, thermally expansible particle|grains may be unevenly distributed on one surface side with the volume reduction at the time of drying, and the adhesiveness with the base material Y or the adhesive force of the adhesion surface may become low. On the other hand, in the solvent-free polymerizable composition, since polymerization proceeds in a state in which thermally expansible particles are uniformly dispersed in the energy-beam polymerizable component to form the pressure-sensitive adhesive layer (X1), the above-described problems are unlikely to occur.

When polymerizable composition (x-1) contains a solvent, it is so preferable that there is little content, With respect to whole quantity (100 mass %) of the active ingredient of polymerizable composition (x-1), Preferably 10 mass % Hereinafter, more preferably, it is 1 mass % or less, More preferably, it is 0.1 mass % or less, More preferably, it is 0.01 mass % or less.

A polymerizable composition (x-1) can be manufactured by mixing an energy-beam polymeric component, thermally expansible particle|grains, and the other component contained as needed. Since the polymerizable composition (x-1) obtained is made to have a high molecular weight by subsequent energy-beam polymerization, when forming a layer, it can adjust to a suitable viscosity with a low molecular-weight energy-beam polymeric component. Therefore, a polymeric composition can be used for formation of adhesive layer (X1) as a coating solution as it is, without adding solvents, such as a diluent.

On the other hand, the pressure-sensitive adhesive layer (X1) formed by irradiating the polymerizable composition (x-1) with an energy ray includes a variety of polymers formed by polymerization of the energy ray polymerizable component and thermally expansible particles dispersed in the polymer. , circumstances exist where it is impossible, or largely impractical, to specify them directly by structure and physical properties.

(Adhesive force in 23 degreeC before thermal expansion of adhesive layer (X1))

The adhesive force in 23 degreeC before thermal expansion of the adhesive layer (X1) becomes like this. Preferably it is 0.1-12.0N/25mm, More preferably, it is 0.5-9.0N/25mm, More preferably, it is 1.0-8.0N/25mm, More preferably, it is 1.2-7.5 N/25 mm.

If the adhesive force at 23 ° C. before thermal expansion of the pressure-sensitive adhesive layer (X1) is 0.1 N / 25 mm or more, unintentional peeling from the adherend at the time of temporarily fixing, displacement of the adherend, etc. can be more effectively suppressed . On the other hand, the peelability at the time of heat peeling can be improved more that the said adhesive force is 12.0 N/25 mm or less.

In addition, in this specification, the adhesive force of an adhesive layer means the adhesive force with respect to the mirror surface of a silicon mirror wafer.

In addition, in this specification, the adhesive force in 23 degreeC before thermal expansion of the adhesive layer (X1) means the value specifically measured according to the method described in the Example.

(Adhesive force in 23 degreeC after thermal expansion of adhesive layer (X1))

The adhesive force in 23 degreeC after thermal expansion of the adhesive layer (X1) becomes like this. Preferably it is 1.5 N/25 mm or less, More preferably, it is 0.05 N/25 mm or less, More preferably, it is 0.01 N/25 mm or less, and still more preferable. Usually it is 0N/25mm. On the other hand, the adhesive force of 0N/25mm means the adhesive force below the measurement limit in the measuring method of the adhesive force at 23 degreeC after thermal expansion mentioned later, and when fixing an adhesive sheet for measurement, the adhesive force is too small and unintentionally The case of peeling is also included.

In this specification, the adhesive force at 23 degreeC after thermal expansion of the adhesive layer (X1) means the value specifically measured according to the method described in the Example.

(Shear storage modulus G' (23) at 23°C of the pressure-sensitive adhesive layer (X1))

Shear storage modulus G' (23) of the pressure-sensitive adhesive layer (X1) at 23° C. is preferably 1.0×10 ^{4 to} 5.0×10 ⁷ Pa, more preferably 5.0×10 ^{4 to} 1.0×10 ⁷ Pa, further Preferably, it is 1.0×10 ^{5 to} 5.0×10 ⁶ Pa.

When the shear storage modulus G' (23) of the pressure-sensitive adhesive layer (X1) is 1.0 × 10 ⁴ Pa or more, positional displacement of the adherend during temporary fixing, excessive sinking of the adherend to the pressure-sensitive adhesive layer (X1), etc. can be suppressed On the other hand, when the shear storage elastic modulus G' (23) is 5.0×10 ⁷ Pa or less, the thermally expansible particles expand easily to form irregularities on the surface of the pressure-sensitive adhesive layer (X1), and the peelability at the time of heat peeling tends to improve.

Meanwhile, in the present specification, the shear storage modulus G' (23) at 23° C. of the pressure-sensitive adhesive layer (X1) means a value measured according to the method described in Examples.

The pressure-sensitive adhesive layer (X1) is a layer containing thermally expansible particles, and the shear storage modulus G' of the pressure-sensitive adhesive layer (X1) may be affected by the thermally expansible particles. From the viewpoint of measuring the shear storage modulus G' excluding the influence of thermally expansible particles, the adhesive layer having the same configuration as the adhesive layer (X1) except that it does not contain thermally expansible particles (hereinafter referred to as "non-expandable adhesive layer ( X1')") may be prepared, and the shear storage modulus G' of the pressure-sensitive adhesive layer may be measured.

(Shear storage modulus G'(23) at 23°C of the non-expandable pressure-sensitive adhesive layer (X1'))

The shear storage modulus G' (23) at 23°C of the non-expandable pressure-sensitive adhesive layer (X1') is preferably 1.0×10 ^{4 to} 5.0×10 ⁷ Pa, more preferably 5.0×10 ^{4 to} 1.0×10 ⁷ Pa, more preferably 1.0×10 ^{5 to} 5.0×10 ⁶ Pa.

When the shear storage elastic modulus G' (23) of the non-expandable pressure-sensitive adhesive layer (X1') is 1.0 × 10 ⁴ Pa or more, the position shift of the adherend at the time of temporarily fixing, excessive decrease of the adherend to the pressure-sensitive adhesive layer (X1) Sitting can be suppressed. On the other hand, when the shear storage elastic modulus G' (23) is 5.0×10 ⁷ Pa or less, the thermally expansible particles expand easily to form irregularities on the surface of the pressure-sensitive adhesive layer (X1), and the peelability at the time of heat peeling tends to improve.

(Shear storage modulus G'(t) at the expansion initiation temperature (t) of the non-expandable pressure-sensitive adhesive layer (X1'))

The shear storage modulus G'(t) at the expansion start temperature (t) of the thermally expansible particles of the non-expandable pressure-sensitive adhesive layer (X1') is preferably 5.0×10 ^{3 to} 1.0×10 ⁷ Pa, more preferably 1.0×10 ^{4 to} 5.0×10 ⁶ Pa, more preferably 5.0×10 ^{4 to} 1.0×10 ⁶ Pa.

When the shear storage modulus G'(t) of the non-expandable pressure-sensitive adhesive layer (X1') is 5.0 × 10 ³ Pa or more, the position shift of the adherend at the time of temporarily fixing, excessive decrease of the adherend to the pressure-sensitive adhesive layer (X1) While sitting etc. can be suppressed, it exists in the tendency which can suppress that an adhesive sheet curls at the time of heat peeling, and can improve handleability. On the other hand, when the shear storage elastic modulus G'(t) is 1.0×10 ⁷ Pa or less, irregularities are easily formed on the surface of the pressure-sensitive adhesive layer (X1) due to the expansion of the thermally expansible particles, and the peelability at the time of heat peeling tends to improve.

Meanwhile, in the present specification, the shear storage modulus G' at a predetermined temperature of the non-expandable pressure-sensitive adhesive layer (X1') means a value measured according to the method described in Examples.

(Thickness at 23°C of the pressure-sensitive adhesive layer (X1))

The thickness in 23 degreeC of adhesive layer (X1) becomes like this. Preferably it is 5-150 micrometers, More preferably, it is 10-100 micrometers, More preferably, it is 20-80 micrometers.

If the thickness at 23 ° C. of the pressure-sensitive adhesive layer (X1) is 5 µm or more, sufficient adhesive force is easily obtained, and unintentional peeling from the adherend at the time of temporarily fixing, displacement of the adherend, etc. can be suppressed tends to be On the other hand, when the thickness at 23 ° C. of the pressure-sensitive adhesive layer (X1) is 150 µm or less, the peelability at the time of heat peeling improves, and it suppresses curling of the adhesive sheet at the time of heat peeling, and can improve handleability. tends to

Meanwhile, in the present specification, the thickness of the pressure-sensitive adhesive layer means a value measured according to the method described in Examples. In addition, the thickness of adhesive layer X1 is a value before expansion|swelling of thermally expansible particle|grains.

<Adhesive layer (X2)>

The pressure-sensitive adhesive layer (X2) is a layer arbitrarily provided on the other surface side of the base material (Y).

Although a thermally expansible layer may be sufficient as adhesive layer (X2), or a nonthermal expansible layer may be sufficient as it, it is preferable that it is a nonthermal expansible layer. In the pressure-sensitive adhesive layer (X1) and the pressure-sensitive adhesive layer (X2), by making the action mechanism for reducing the adhesive force of the pressure-sensitive adhesive layer different from each other, when performing a process for reducing the adhesive strength of either one of the pressure-sensitive adhesive layers, the other pressure-sensitive adhesive layer is unintentionally It can suppress that the adhesive force of

When the pressure-sensitive adhesive layer (X2) is a non-thermal expandable layer, the volume change rate (%) of the pressure-sensitive adhesive layer (X2) calculated from the above formula is less than 5%, preferably less than 2%, more preferably less than 1%, more Preferably less than 0.1%, even more preferably less than 0.01%.

Although it is preferable not to contain thermally expansible particle|grains, adhesive layer (X2) may contain thermally expansible particle|grains in the range which is not contrary to the objective of this invention.

When the pressure-sensitive adhesive layer (X2) contains thermally expansible particles, the content is preferably as small as possible, with respect to the total mass (100 mass%) of the pressure-sensitive adhesive layer (X2), preferably less than 3 mass%, more preferably It is less than 1 mass %, More preferably, it is less than 0.1 mass %, More preferably, it is less than 0.01 mass %, More preferably, it is less than 0.001 mass %.

It is preferable to form an adhesive layer (X2) from the adhesive composition (x-2) containing adhesive resin. Hereinafter, each component contained in an adhesive composition (x-2) is demonstrated.

(Adhesive composition (x-2))

The pressure-sensitive adhesive composition (x-2) contains a pressure-sensitive adhesive resin, and, if necessary, a crosslinking agent, a tackifier, a polymerizable compound, a polymerization initiator, and additives for pressure-sensitive adhesives used in general pressure-sensitive adhesives other than each of the above components. there may be

[Adhesive resin]

As adhesive resin, the said resin independently has adhesiveness, and what is necessary is just a polymer whose mass average molecular weight (Mw) is 10,000 or more.

From a viewpoint of the mass average molecular weight (Mw) of adhesive resin improving the adhesive force of adhesive layer (X2) more, Preferably it is 10,000-2 million, More preferably, it is 20,000-1,500,000, More preferably, 30,000 ~100 million.

Examples of the adhesive resin include rubber-based resins such as acrylic resins, urethane-based resins, and polyisobutylene-based resins, polyester-based resins, olefin-based resins, silicone-based resins, and polyvinyl ether-based resins.

These adhesive resins may be used individually by 1 type, and may use 2 or more types together.

In addition, when these adhesive resins are a copolymer which has 2 or more types of structural units, any of a block copolymer, a random copolymer, and a graft copolymer may be sufficient as the form of the said copolymer.

The pressure-sensitive adhesive composition (x-2) containing the pressure-sensitive adhesive resin is preferably a pressure-sensitive adhesive composition cured by irradiation with energy rays from the viewpoint of differentiating the mechanism of lowering the adhesive force with the pressure-sensitive adhesive layer (X1), the pressure-sensitive adhesive resin, It is more preferable that it is resin which has an energy-beam polymerizable functional group in the side chain of said adhesive resin. By forming from the said adhesive composition, adhesive layer (X2) can be hardened|cured by energy-beam irradiation, and it can be set as the adhesive layer in which adhesive force falls.

As an energy-beam polymerizable functional group, what has carbon-carbon double bonds, such as a (meth)acryloyl group, a vinyl group, and an allyl group, is mentioned, for example.

As an energy beam, the ultraviolet-ray with easy handling among the above-mentioned is preferable.

In addition, the pressure-sensitive adhesive composition (x-2), together with the pressure-sensitive adhesive resin having an energy-beam polymerizable functional group, or instead of the pressure-sensitive adhesive resin having an energy-beam polymerizable functional group, contains a monomer or prepolymer having an energy-beam polymerizable functional group, there may be

As a monomer or prepolymer which has an energy-beam polymerizable functional group, the thing similar to the energy-beam polymeric component contained in said polymerizable composition (x-1) is mentioned.

When making an adhesive composition (x-2) into the adhesive composition hardened|cured by irradiation of an energy ray, it is preferable that the said adhesive composition contains a photoinitiator further.

By containing a photoinitiator, superposition|polymerization of an energy-beam polymeric component can advance more efficiently.

As a photoinitiator, the thing similar to the photoinitiator which the polymerizable composition (x-1) may contain is mentioned.

The content of the photoinitiator is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, still more preferably 0.01 to 10 parts by mass, with respect to 100 parts by mass of the total amount of the adhesive resin having an energy ray polymerizable functional group, a monomer, and a prepolymer. It is 0.05-2 mass parts.

It is preferable that adhesive resin contains an acrylic resin from a viewpoint of expressing the outstanding adhesive force.

The content of the acrylic resin in the pressure-sensitive adhesive composition (x-2) is preferably 30 to 100 mass%, more preferably 30 to 100 mass% with respect to the total amount (100 mass%) of the pressure-sensitive adhesive resin contained in the pressure-sensitive adhesive composition (x-2). is 50-100 mass %, More preferably, it is 70-100 mass %, More preferably, it is 85-100 mass %.

To [ content of the adhesive resin in an adhesive composition (x-2) / whole quantity (100 mass %) of the active ingredient of an adhesive composition (x-2)), Preferably it is 35-100 mass %, More preferably, it is 50 -100 mass %, More preferably, it is 60-98 mass %, More preferably, it is 70-95 mass %.

[crosslinking agent]

In one aspect of the present invention, when the pressure-sensitive adhesive composition (x-2) contains an adhesive resin having a functional group, the pressure-sensitive adhesive composition (x-2) preferably further contains a crosslinking agent.

The said crosslinking agent reacts with the adhesive resin which has a functional group, and uses the said functional group as a bridge|crosslinking origin to bridge|crosslink adhesive resins.

As a crosslinking agent, an isocyanate type crosslinking agent, an epoxy type crosslinking agent, an aziridine type crosslinking agent, a metal chelate type crosslinking agent, etc. are mentioned, for example.

A crosslinking agent may be used individually by 1 type, and may use 2 or more types together.

Among these crosslinking agents, an isocyanate-type crosslinking agent is preferable from a viewpoint of raising cohesive force and improving adhesive force, and viewpoints, such as easiness of availability.

The content of the crosslinking agent is appropriately adjusted according to the number of functional groups in the adhesive resin, but with respect to 100 parts by mass of the adhesive resin having a functional group, preferably 0.01 to 10 parts by mass, more preferably 0.03 to 7 parts by mass, further Preferably it is 0.05-5 mass parts.

[Tackifier]

One aspect of this invention WHEREIN: The adhesive composition (x-2) may contain the tackifier further from a viewpoint of improving adhesive force more.

As a tackifier which adhesive composition (x-2) may contain, the thing equivalent to the tackifier which polymeric composition (x-1) may contain can be used.

[Additives for Adhesives]

As an additive for adhesives, the same thing as the additive for adhesives which the polymerizable composition (x-1) may contain is mentioned.

On the other hand, when the pressure-sensitive adhesive composition (x-2) does not contain thermally expansible particles, since there is no need to avoid heating and drying the thermally expansible particles to an expansion start temperature (t) or higher, the pressure-sensitive adhesive composition (x-2) is, You may contain a solvent as needed.

The adhesive composition (x-2) can be manufactured by mixing an adhesive resin, the crosslinking agent used as needed, a tackifier, the additive for adhesives, etc.

[Adhesive force of the pressure-sensitive adhesive layer (X2)]

The adhesive force on the adhesion surface of the pressure-sensitive adhesive layer (X2) is preferably 0.1 to 10.0 N/25 mm, more preferably 0.2 to 8.0 N/25 mm, still more preferably 0.4 to 6.0 N/25 mm, more More preferably, it is 0.5-4.0 N/25 mm.

If the adhesive force on the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer (X2) is 0.1 N/25 mm or more, unintentional peeling from the adherend at the time of temporarily fixing, position shift of the adherend, etc. can be more effectively suppressed. On the other hand, if the said adhesive force is 10.0 N/25 mm or less, it will become easy to peel, without giving damage etc. to a to-be-adhered body.

[Shear storage modulus G' (23) at 23°C of the pressure-sensitive adhesive layer (X2)]

Shear storage modulus G' (23) of the pressure-sensitive adhesive layer (X2) at 23° C. is preferably 5.0×10 ^{3 to} 1.0×10 ⁷ Pa, more preferably 1.0×10 ^{4 to} 5.0×10 ⁶ Pa, further Preferably it is 5.0×10 ^{4 to} 1.0×10 ⁶ Pa.

When the shear storage modulus G' (23) of the pressure-sensitive adhesive layer (X2) is 5.0 × 10 ³ Pa or more, positional shift of the adherend during temporary fixing, excessive sinking of the adherend to the pressure-sensitive adhesive layer (X2), etc. tend to be restrained. On the other hand, when the shear storage modulus G'(23) is 1.0×10 ⁷ Pa or less, the adhesion to the adherend tends to improve.

On the other hand, in the present specification, the shear storage modulus G' (23) at 23 ° C. of the pressure-sensitive adhesive layer (X2) can be measured according to the same method as the shear storage modulus G' at 23 ° C. of the pressure-sensitive adhesive layer (X1). have.

[Thickness of the pressure-sensitive adhesive layer (X2) at 23°C]

The thickness in 23 degreeC of adhesive layer (X2) becomes like this. Preferably it is 5-150 micrometers, More preferably, it is 8-100 micrometers, More preferably, it is 12-70 micrometers, More preferably, it is 15-50 micrometers.

When the thickness of the pressure-sensitive adhesive layer (X2) at 23 ° C. is 5 µm or more, sufficient adhesive force is easily obtained, and unintentional peeling from the adherend at the time of temporary fixing, displacement of the adherend, etc. can be suppressed tends to be On the other hand, there exists a tendency for handling of an adhesive sheet to become easy that the thickness in 23 degreeC of adhesive layer X2 is 150 micrometers or less.

<Leijae Lee>

As a release material, the release sheet by which the double-sided peeling process was carried out, the release sheet by which the single-sided peeling process was carried out, etc. are used, The thing which apply|coated the release material on the base material for release materials, etc. are mentioned.

As a base material for release materials, a plastic film, paper, etc. are mentioned, for example. As a plastic film, For example, Polyester resin films, such as polyethylene terephthalate resin, polybutylene terephthalate resin, and polyethylene naphthalate resin; Olefin resin films, such as a polypropylene resin and a polyethylene resin, etc. are mentioned, As paper, fine paper, glassine paper, kraft paper, etc. are mentioned, for example.

As a release material, For example, rubber type elastomers, such as silicone type resin, an olefin type resin, an isoprene type resin, a butadiene type resin; Long-chain alkyl-type resin, alkyd-type resin, fluorine-type resin, etc. are mentioned. A release material may be used individually by 1 type, and may use 2 or more types together.

The thickness of a release material becomes like this. Preferably it is 10-200 micrometers, More preferably, it is 20-150 micrometers, More preferably, it is 35-80 micrometers.

[Method for producing adhesive sheet]

In the method for producing the pressure-sensitive adhesive sheet of one aspect of the present invention, the method for forming the pressure-sensitive adhesive layer (X1) is to apply an energy beam to the polymerizable composition (x-1) containing the energy-beam polymerizable component and the thermally expansible particles. It is a manufacturing method of an adhesive sheet including the process of irradiating and forming the polymer of the said energy-beam polymerizable component.

The method of forming the pressure-sensitive adhesive layer (X1) preferably includes the following steps I and II.

Step I: Step of forming a polymerizable composition layer made of the polymerizable composition (x-1) on one surface side of the base material (Y)

Process II: The process of forming the polymer of the said energy-beam polymeric component by irradiating an energy-beam to the said polymeric composition layer, and forming the adhesive layer (X1) containing the said polymer and the said thermally expansible particle.

<Process Ⅰ>

Although process I will not be specifically limited if it is a process of forming a polymeric composition layer in one surface side of a base material (Y), It is preferable to include the following processes I-1 - I-3.

Step I-1: A step of forming a polymerizable composition layer by coating the polymerizable composition (x-1) on the release treatment surface of the release material

Step I-2: Step of irradiating the polymerizable composition layer with a first energy ray to prepolymerize the energy ray polymerizable component in the polymerizable composition layer

Step I-3: Step of affixing the base material (Y) to the polymerizable composition layer after the first energy ray irradiation

(Process Ⅰ-1)

Step I-1 is a step of forming a polymerizable composition layer by applying the polymerizable composition (x-1) on the release treatment surface of the release material.

In step I-1, as a method of applying the polymerizable composition (x-1) to the release material, for example, a spin coating method, a spray coating method, a bar coating method, a knife coating method, a roll coating method, a blade coating method , a die coating method, a gravure coating method, and the like.

The polymerizable composition (x-1) is preferably a solvent-free polymerizable composition as described above. When the polymerizable composition (x-1) is a solvent-free polymerizable composition, it is not necessary to perform the solvent heat drying step in this step. On the other hand, when polymerizable composition (x-1) contains a solvent in the range which does not go against the objective of this invention, after apply|coating polymeric composition (x-1), although heat-drying may be performed, in that case The heating temperature is set to be less than the expansion start temperature (t) of the thermally expansible particles.

(Process Ⅰ-2)

Process I-2 is a process of performing 1st energy-beam irradiation with respect to the polymeric composition layer formed in process I-1, and prepolymerizing the energy-beam polymeric component in a polymeric composition layer.

1st energy-beam irradiation is performed for the purpose of making a polymeric composition high viscosity by prepolymerizing an energy-beam polymeric component, and improving the shape retentivity of a polymeric composition layer.

In the first energy ray irradiation, the energy ray polymerizable component is not completely polymerized, but only prepolymerized. Thereby, the adhesiveness of the polymeric composition layer in process I-3 and the base material (Y) can be improved.

As an energy ray used for 1st energy ray irradiation of process I-2, the ultraviolet-ray with which handling is easy among the above-mentioned is preferable.

The illuminance of the ultraviolet rays in the first energy ray irradiation is preferably 70 to 250 mW/cm 2 , more preferably 100 to 200 mW/cm 2 , and still more preferably 130 to 170 mW/cm 2 . Moreover, the light quantity of the ultraviolet-ray in 1st energy ray irradiation becomes like this. Preferably it is 40-200 mJ/cm<2>, More preferably, it is 60-150 mJ/cm<2>, More preferably, it is 80-120 mJ/cm<2>.

1st energy-beam irradiation may be performed once, and may be divided into multiple times and may be performed. Moreover, in order to suppress the temperature rise of the polymeric composition layer by polymerization heat etc., you may carry out, cooling a polymeric composition layer.

(Process Ⅰ-3)

Process I-3 is a process of affixing the base material (Y) to the polymeric composition layer after 1st energy-beam irradiation.

The method of affixing the base material (Y) to the polymeric composition layer is not specifically limited, For example, the method of laminating the base material (Y) on the surface of the polymerizable composition layer is mentioned.

Lamination may be performed while heating or may be performed without heating, but from the viewpoint of suppressing expansion of thermally expansible particles, it is preferable to perform lamination without heating. At this time, even if it is non-heating, the polymeric composition layer prepolymerized by 1st energy-beam irradiation has favorable adhesiveness with respect to the base material (Y).

<Process Ⅱ>

Step II is a step of forming a polymer of an energy-beam polymerizable component by irradiating an energy ray to the polymerizable composition layer formed in step I, and forming a pressure-sensitive adhesive layer (X1) containing the polymer and thermally expansible particles. .

Here, when performing 1st energy-beam irradiation in process I, energy-beam irradiation in process II turns into 2nd energy-beam irradiation with respect to the polymeric composition layer after preliminary polymerization.

Unlike 1st energy-beam irradiation, it is preferable to perform energy-beam irradiation of process II to the extent that superposition|polymerization of an energy-beam polymeric component does not progress substantially even if it irradiates an energy-beam further.

By energy-beam irradiation of process II, superposition|polymerization of an energy-beam polymeric component advances, and the polymer of the energy-beam polymeric component which comprises the adhesive layer (X1) is formed.

As the energy ray used for the energy ray irradiation in step II, an easy-to-handle ultraviolet ray among those described above is preferable.

The illuminance of the ultraviolet rays in the energy ray irradiation in Step II is preferably 100 to 350 mW/cm 2 , more preferably 150 to 300 mW/cm 2 , and still more preferably 180 to 250 mW/cm 2 .

The amount of ultraviolet light in the energy ray irradiation in Step II is preferably 500 to 4,000 mJ/cm 2 , more preferably 1,000 to 3,000 mJ/cm 2 , and still more preferably 1,500 to 2,500 mJ/cm 2 .

The energy-beam irradiation of process II may be performed once, and may be divided into multiple times and may be performed. Moreover, in order to suppress the temperature rise of the polymeric composition layer by polymerization heat etc., you may carry out, cooling a polymeric composition layer.

On the other hand, when Step I includes Steps I-1 to I-3, the polymerizable composition layer is obtained as an intermediate layer of a laminate in which a release material, a polymerizable composition layer, and a substrate (Y) are laminated in this order. can At this time, you may perform 2nd energy-beam irradiation with respect to the laminated body which has the said structure. In that case, it is preferable that at least one selected from the release material and the substrate (Y) has energy ray permeability from the viewpoint of making it possible to sufficiently irradiate an energy ray to the polymerizable composition layer present as an intermediate layer of the laminate. do.

It is preferable not to include the process of heating a polymeric composition from a viewpoint of suppressing expansion|swelling of thermally expansible particle also in any of the processes included in said process I and II.

On the other hand, "heating" herein means, for example, intentionally heating during drying or lamination, etc., by heat imparted to the polymerizable composition by energy ray irradiation and polymerization of the energy ray polymerizable composition. It shall not include the temperature rise by the heat of polymerization etc. which generate|occur|produce.

The heating temperature in the case of including the step of heating the polymerizable composition as needed is preferably "a temperature lower than the expansion initiation temperature (t)", more preferably "expansion initiation temperature (t) - 5°C" or less , More preferably, it is "expansion start temperature (t) - 10 degreeC" or less, More preferably, it is "expansion initiation temperature (t) - 15 degreeC" or less. Moreover, when the temperature of a polymeric composition rises unintentionally, it is preferable to cool so that the temperature of a polymeric composition may become the said temperature range.

When the adhesive sheet of one aspect of this invention has the structure of the said double-sided adhesive sheet, it is preferable that the manufacturing method of the adhesive sheet of one aspect of this invention further includes the following process III.

<Process Ⅲ>

Step III: Step of forming the pressure-sensitive adhesive layer (X2) on the other side of the substrate (Y)

What is necessary is just to determine the method of forming adhesive layer (X2) suitably according to the kind of composition which comprises adhesive layer (X2). For example, when forming adhesive layer (X2) using adhesive composition (x-2), it is preferable that process III includes the following processes III-1 and III-2.

Step III-1: A step of forming the pressure-sensitive adhesive layer (X2) by applying the pressure-sensitive adhesive composition (x-2) to one surface of the release material

Step III-2: Step of affixing the pressure-sensitive adhesive layer (X2) formed in Step III-1 to the other surface side of the substrate (Y)

As a method of apply|coating the adhesive composition (x-2) in process III-1, the method similar to the method mentioned as a method of apply|coating polymeric composition (x-1) in process I-1 is mentioned. Moreover, when adhesive layer (X2) contains a solvent, after apply|coating adhesive composition (x-2), you may include the process of drying a coating film.

On the other hand, as described above, the release material used in step III-1 and the release material used in step I-1 are peeled from the viewpoint of suppressing the phenomenon in which the pressure-sensitive adhesive layer is divided and peeled with the two release materials. It is preferable that the forces are designed to be different from each other.

In step III-2, as a method of affixing the pressure-sensitive adhesive layer (X2) to the substrate (Y), the same method as in the method of affixing the substrate (Y) to the polymerizable composition layer in the step 1-3 is mentioned, a preferred embodiment The same is also true.

[Applications and How to Use the Adhesive Sheet]

Since the adhesive sheet of one aspect of the present invention can be peeled by heating at a low temperature while having sufficient adhesive force at the time of temporarily fixing, it is applicable to various uses. Specifically, for example, a dicing sheet used when dicing an adherend such as a semiconductor wafer, a back grind sheet used in a process of grinding an adherend, and a semiconductor chip divided into pieces by dicing. An expand tape used to increase the distance between complexes, a transfer tape used to reverse the front and back of an adherend such as a semiconductor chip, a temporary fixing sheet used for temporarily fixing an inspection object, etc. do.

Although it does not specifically limit as a to-be-adhered body of the adhesive sheet of one aspect of this invention, For example, a semiconductor chip, a semiconductor wafer, a compound semiconductor, a semiconductor package, an electronic component, a sapphire board|substrate, a display, board|substrate for panels, etc. are mentioned. . Since the pressure-sensitive adhesive sheet of one aspect of the present invention can be peeled by heating at a low temperature, it is suitable for temporarily fixing an adherend that is susceptible to thermal change such as a semiconductor chip with DAF.

The heating temperature at the time of heating and peeling the pressure-sensitive adhesive sheet of one aspect of the present invention from the adherend is equal to or higher than the expansion start temperature (t) of the thermally expandable particles, preferably “a temperature higher than the expansion start temperature (t)”, more Preferably, "expansion initiation temperature (t) + 2°C" or more, more preferably "expansion initiation temperature (t) + 4°C" or more, and still more preferably "expansion initiation temperature (t) + 5°C" or more. am. In addition, from the viewpoint of energy saving and suppressing the thermal change of the adherend at the time of peeling by heating, preferably "expansion start temperature (t) + 50 ° C." or less, more preferably "expansion start temperature (t)" +40°C” or less, more preferably “expansion start temperature (t)+20°C” or less.

In addition, the heating temperature at the time of heat peeling is, from a viewpoint of suppressing the thermal change of a to-be-adhered body, in the range of expansion initiation temperature (t) or more, Preferably it is 120 degrees C or less, More preferably, it is 115 degrees C or less, More preferably. Preferably, it is 110°C or less, and even more preferably, it is 105°C or less.

It will not specifically limit if it can heat more than the temperature at which thermally expansible particle|grains expand as a method of heating, For example, Electrothermal heater; dielectric heating; self-heating; Heating by electromagnetic waves, such as infrared rays, such as near-infrared rays, mid-infrared rays, and far-infrared rays, etc. can be used suitably. In addition, the heating system may be any heating system of a contact heating system, such as a heating roller and a hot press, and a non-contact heating system, such as an atmospheric heating apparatus and infrared irradiation.

[Method for manufacturing semiconductor device]

This invention also provides the manufacturing method of the semiconductor device using the adhesive sheet of one aspect of this invention.

As one aspect of the manufacturing method of the semiconductor device of this invention, the aspect using the adhesive sheet of one aspect of this invention as a sheet for temporarily fixing for processing a to-be-adhered body (henceforth "the manufacturing method of the semiconductor device of a 1st aspect") also referred to as ).

<The manufacturing method of the semiconductor device of 1st aspect>

As a more specific aspect of the manufacturing method of the semiconductor device of the first aspect, the object to be processed is affixed to the pressure-sensitive adhesive sheet of one aspect of the present invention, and the object to be processed is subjected to one or more treatments selected from grinding treatment and slicing treatment (hereinafter referred to as slicing treatment). , "processing treatment"), and after performing the treatment, heating the pressure-sensitive adhesive sheet to a temperature above the expansion start temperature (t) and below 120° C. to expand the pressure-sensitive adhesive layer (X1), The manufacturing method of a semiconductor device is mentioned.

In addition, in this specification, a "semiconductor device" refers to the general device which can function by using semiconductor characteristics. For example, a wafer with an integrated circuit, a thinned wafer with an integrated circuit, a chip with an integrated circuit, a thinned chip with an integrated circuit, an electronic component including the chip, and the electronic component and electronic devices.

In the manufacturing method of the semiconductor device of a 1st aspect, adhesive layer (X1) may be sufficient as the adhesive layer of the adhesive sheet which affixes a processing object, and when an adhesive sheet is a double-sided adhesive sheet, the adhesive layer (X2) may be sufficient as it.

When an adhesive sheet is a double-sided adhesive sheet, it is preferable to affix a process object to one adhesive layer, and to affix a support body to the other adhesive layer. By fixing the object to be processed to the support through the pressure-sensitive adhesive sheet, it is possible to suppress vibration of the object to be processed, misalignment, breakage of the fragile object, and the like during processing, thereby improving processing precision and processing speed. At this time, the support may be affixed to the pressure-sensitive adhesive layer (X1) and the object to be processed may be attached to the pressure-sensitive adhesive layer (X2). It could be the sun.

In the case where the support is affixed to the pressure-sensitive adhesive layer (X1) and the object to be processed is attached to the pressure-sensitive adhesive layer (X2), the support is attached to the pressure-sensitive adhesive layer (X1) excellent in releasability after heat treatment, whereby the support is made of a hard material Even if it becomes a thing, it can peel by heating, without bending an adhesive sheet and a support body. In addition, the pressure-sensitive adhesive layer (X2) may be appropriately selected in composition according to the type of object to be processed, for example, if the pressure-sensitive adhesive layer (X2) is an pressure-sensitive adhesive layer in which adhesive strength is lowered by irradiation with energy rays, it is derived from thermally expandable particles. It can be peeled off without contaminating the object to be processed by the residue or the like.

On the other hand, in the case where the object to be processed is affixed to the pressure-sensitive adhesive layer (X1) and the support is adhered to the pressure-sensitive adhesive layer (X2), the object to be processed is attached to the pressure-sensitive adhesive layer (X1) excellent in releasability after heat treatment, whereby heat peeling after processing In this case, since the object to be processed can be peeled from the pressure-sensitive adhesive sheet by self peeling, damage to the object to be processed can be reduced.

When a double-sided adhesive sheet is used as the adhesive sheet of one aspect of the present invention, the manufacturing method of the semiconductor device of the first aspect is a manufacturing method (hereinafter also referred to as "manufacturing method A") including the following steps 1A to 5A desirable.

Process 1A: The process of affixing a processing object to the adhesive layer (X2) which an adhesive sheet has, and affixing a support body to adhesive layer (X1)

Step 2A: A step of performing one or more treatments selected from grinding treatment and shredding treatment on the object to be processed

Step 3A: Step of affixing a thermosetting film on the surface of the object to be processed on the opposite side to the pressure-sensitive adhesive layer (X2)

Step 4A: A step of separating the pressure-sensitive adhesive layer (X1) from the support by heating the pressure-sensitive adhesive sheet to a temperature above the expansion start temperature (t) and below 120°C

Step 5A: Step of separating the pressure-sensitive adhesive layer (X2) and the object to be processed

Hereinafter, a method of manufacturing a semiconductor device including steps 1A to 5A will be described with reference to the drawings. In addition, in the following description, although the example in the case of using a semiconductor wafer as a processing object is mainly demonstrated, the case of another processing object is also the same.

(Process 1A)

Process 1A is a process of affixing a process object to the adhesive layer (X2) which an adhesive sheet has, and affixing a support body to adhesive layer (X1).

3, the sectional drawing explaining the process of affixing the semiconductor wafer W to the adhesive layer X2 which the adhesive sheet 2a has, and affixing the support body 3 to the adhesive layer X1 is shown.

The semiconductor wafer W is affixed so that the surface W1 which is a circuit surface may become the adhesive layer X2 side.

A silicon wafer may be sufficient as the semiconductor wafer W, and wafers, such as gallium arsenide, silicon carbide, sapphire, lithium tantalumate, lithium niobate, gallium nitride, indium phosphorus, and a glass wafer may be sufficient as the semiconductor wafer W.

The thickness before grinding of the semiconductor wafer W is 500-1000 micrometers normally.

The circuit which the surface W1 of the semiconductor wafer W has can be formed according to conventionally general-purpose methods, such as an etching method and a lift-off method, for example.

What is necessary is just to select the material of the support body 3 suitably after considering requested|required characteristics, such as mechanical strength and heat resistance, according to the kind of object to be processed, processing content, etc.

As a material of the support body 3, For example, Metal materials, such as SUS; non-metallic inorganic materials such as glass and silicon wafers; resin materials such as epoxy resins, ABS resins, acrylic resins, engineering plastics, super engineering plastics, polyimide resins, and polyamideimide resins; Composite materials, such as a glass epoxy resin, etc. are mentioned, Among these, SUS, glass, and a silicon wafer are preferable.

As said engineering plastics, nylon, polycarbonate (PC), polyethylene terephthalate (PET), etc. are mentioned, for example.

As said super engineering plastics, polyphenylene sulfide (PPS), polyether sulfone (PES), polyether ether ketone (PEEK) etc. are mentioned, for example.

It is preferable that the support body 3 is affixed on the whole surface of the adhesion surface of the adhesive layer X1. Therefore, it is preferable that the area of the surface of the support body 3 on the side affixed to the adhesion surface of the adhesive layer X1 is more than the area of the adhesion surface of the adhesive layer X1. Moreover, it is preferable that the surface of the support body 3 on the side affixed to the adhesion surface of the adhesive layer X1 is flat.

Although the shape of the support body 3 is not specifically limited, It is preferable that it is plate-shaped.

The thickness of the support body 3 may be appropriately selected in consideration of the required characteristics, but is preferably 20 µm or more and 50 mm or less, and more preferably 60 µm or more and 20 mm or less.

(Process 2A)

Step 2A is a step of performing one or more treatments selected from grinding treatment and shredding treatment on the object to be processed.

As one or more processes selected from a grinding process and a shredding process, For example, grinding process using a grinder etc.; Segmentation processing by the blade dicing method, the laser dicing method, the stealth dicing (trademark) method, the blade sun dicing method, the stealth sun dicing method, etc. are mentioned.

Among these, fragmentation processing by the stealth dicing method, grinding processing and fragmentation processing by the blade sun dicing method, grinding processing and fragmentation processing by the stealth sun dicing method are suitable, and grinding processing by the blade sun dicing method and Piece processing, grinding processing by the stealth sun dicing method, and fragmentation processing are more suitable.

The stealth dicing method is a method in which a modified region is formed inside a semiconductor wafer by irradiation of a laser beam, and the modified region is used as a division starting point to separate the semiconductor wafer into pieces. The modified region formed on the semiconductor wafer is a portion brittled by multiphoton absorption, and the semiconductor wafer is parallel to the wafer surface by expansion and stress is applied in the direction in which the wafer is expanded. As cracks extend toward the front and back surfaces of the semiconductor wafer, they are divided into semiconductor chips. That is, the modified region is formed along the dividing line at the time of segmentation.

A modified region is formed in the inside of a semiconductor wafer by irradiation of the laser beam which focused on the inside of a semiconductor wafer. The incident surface of the laser beam may be the front surface or the back surface of the semiconductor wafer. In addition, the surface on which the adhesive sheet was affixed may be sufficient as the laser beam incident surface, and in that case, a laser beam is irradiated to a semiconductor wafer through an adhesive sheet.

The blade sun dicing method is also called the DBG method (Dicing Before Grinding). In the blade sun dicing method, after forming a groove in the semiconductor wafer to a depth shallower than the thickness in advance along a line to be divided, the semiconductor wafer is subjected to back grinding until the grinding surface reaches at least the groove, and is thinned into pieces way to get angry. The groove to which the grinding surface reached becomes a notch penetrating a semiconductor wafer, and a semiconductor wafer is divided|segmented by the said notch, and is divided into semiconductor chips. The grooves formed in advance are usually provided on the surface (circuit surface) of a semiconductor wafer, and can be formed, for example, by dicing using a conventionally well-known wafer dicing apparatus equipped with a dicing blade. .

The stealth sun dicing method is also called the SDBG method (Stealth Dicing Before Grinding). Like the stealth dicing method, the stealth sun dicing method is a method of forming a modified region inside a semiconductor wafer by irradiation with laser light, and using the modified region as a division starting point to separate the semiconductor wafer into pieces. It differs from the stealth dicing method in that the semiconductor wafer is divided into semiconductor chips while thinning the semiconductor wafer. Specifically, while the back surface of the semiconductor wafer having the modified region is ground and thinned, the crack is extended from the modified region as a starting point by the pressure applied to the semiconductor wafer toward the bonding surface with the pressure-sensitive adhesive layer of the semiconductor wafer, The wafer is divided into semiconductor chips.

On the other hand, the grinding thickness after forming the modified region may be a thickness reaching the modified region, but it may be ground to a position close to the modified region and cut with a machining pressure such as a grinding wheel without strictly reaching the modified region.

When the semiconductor wafer W is divided into pieces according to the blade sun dicing method, it is preferable to form a groove in advance on the surface W1 of the semiconductor wafer W to be affixed to the pressure-sensitive adhesive layer X2 in step 1A.

On the other hand, when the semiconductor wafer W is divided into pieces according to the stealth sun dicing method, the semiconductor wafer W affixed to the pressure-sensitive adhesive layer X2 in step 1A may be irradiated with laser light to form a modified region in advance, You may irradiate a laser beam with respect to the semiconductor wafer W affixed on the adhesive layer X2, and you may form a modified area|region.

4, sectional drawing explaining the process of forming the some modified region 5 using the laser beam irradiation apparatus 4 with respect to the semiconductor wafer W affixed to the adhesive layer X2 is shown.

A laser beam is irradiated from the back surface W2 side of the semiconductor wafer W, and the some modified region 5 is formed in the inside of the semiconductor wafer W at substantially equal intervals.

In Fig. 5, the back surface W2 of the semiconductor wafer W on which the modified region 5 is formed is ground with a grinder 6, and the semiconductor wafer W is cut with the modified region 5 as a starting point. A cross-sectional view is shown for explaining a process of dividing into pieces into a plurality of semiconductor chips CP while thinning them.

The semiconductor wafer W on which the modified region 5 is formed is, for example, in a state in which the support 3 supporting the semiconductor wafer W is fixed on a fixing table such as a chuck table, and the rear surface W2 thereof This is grinding.

The thickness of the semiconductor chip CP after grinding becomes like this. Preferably it is 5-100 micrometers, More preferably, it is 10-45 micrometers. Moreover, when performing a grinding process and a fragmentation process according to the stealth sun dicing method, it becomes easy to set the thickness of the semiconductor chip CP obtained by grinding to 50 micrometers or less, More preferably, it is 10-45 micrometers.

The size of the semiconductor chip CP after grinding in a plan view is preferably less than 600 mm 2 , more preferably less than 400 mm 2 , still more preferably less than 300 mm 2 . On the other hand, to see in a plane means to see in the thickness direction.

The planar shape of the semiconductor chip CP after segmentation may be a quadrangle, and elongate shapes, such as a rectangle, may be sufficient as it.

(Process 3A)

Step 3A is a step of affixing a thermosetting film on the surface of the object to be processed on the opposite side to the pressure-sensitive adhesive layer (X2).

In FIG. 6, the process of affixing the thermosetting film 7 provided with the support sheet 8 on the surface on the opposite side to the adhesive layer X2 of several semiconductor chip CP obtained by giving the said process is demonstrated. A cross-sectional view is shown.

The thermosetting film 7 is a film which has thermosetting property obtained by forming into a film the resin composition containing at least a thermosetting resin into a film, and is used as an adhesive agent at the time of mounting the semiconductor chip CP on a board|substrate. The thermosetting film 7 may contain the hardening|curing agent of the said thermosetting resin, a thermoplastic resin, an inorganic filler, a hardening accelerator, etc. as needed.

As the thermosetting film 7, the thermosetting film generally used as a die-bonding film, a die touch film, etc. can be used, for example.

Although the thickness of the thermosetting film 7 is not specifically limited, Usually, it is 1-200 micrometers, Preferably it is 3-100 micrometers, More preferably, it is 5-50 micrometers.

The support sheet 8 should just be what can support the thermosetting film 7, For example, resin, metal, and a paper material contained as the base material Y which the adhesive sheet of one aspect of this invention has. and the like.

As a method of affixing the thermosetting film 7 to the some semiconductor chip CP, the method by lamination is mentioned, for example.

A lamination may be performed, heating, and may be performed by non-heating. The heating temperature in the case of carrying out the lamination while heating, from the viewpoint of suppressing the expansion of the thermally expandable particles and from the viewpoint of suppressing the thermal change of the adherend, is preferably "a temperature lower than the expansion start temperature (t)", more preferably is "expansion start temperature (t) - 5 ° C." or less, more preferably "expansion initiation temperature (t) - 10 ° C." or less, and still more preferably "expansion initiation temperature (t) - 15 ° C." or less.

(Process 4A)

Step 4A is a step of separating the pressure-sensitive adhesive layer (X1) from the support by heating the pressure-sensitive adhesive sheet to the expansion initiation temperature (t) or higher and to 120°C or lower.

In FIG. 7, sectional drawing explaining the process of heating the adhesive sheet 2a and isolate|separating the adhesive layer X1 and the support body 3 is shown.

The heating temperature in step 4A is equal to or higher than the expansion initiation temperature (t) of the thermally expansible particles, and in the range of 120° C. or lower, preferably “a temperature higher than the expansion initiation temperature (t)”, more preferably “expansion initiation temperature (t)” Initiation temperature (t) + 2°C” or more, more preferably “expansion initiation temperature (t) + 4°C” or more, and still more preferably “expansion initiation temperature (t) + 5°C” or more. In addition, the heating temperature in step 4A is in the range of 120° C. or less, preferably “expansion start temperature (t) + 50” from the viewpoint of energy saving and suppressing thermal change of the adherend during heat peeling C" or less, More preferably, it is "expansion start temperature (t) + 40 degreeC" or less, More preferably, it is "expansion start temperature (t) + 20 degreeC" or less.

The heating temperature in step 4A is preferably 115°C or less, more preferably 110°C or less, still more preferably 105°C or less, within the range of the expansion start temperature (t) or more, from the viewpoint of suppressing thermal change of the adherend. ℃ or less.

(Process 5A)

Step 5A is a step of separating the pressure-sensitive adhesive layer (X2) and the object to be processed.

8 is a cross-sectional view for explaining a step of separating the pressure-sensitive adhesive layer X2 and the plurality of semiconductor chips CP.

What is necessary is just to select the method of isolate|separating the adhesive layer X2 and some semiconductor chip CP suitably according to the kind of adhesive layer X2. For example, in the case where the pressure-sensitive adhesive layer (X2) is a pressure-sensitive adhesive layer in which the adhesive force is lowered by irradiation with an energy ray, the pressure-sensitive adhesive layer (X2) may be irradiated with an energy ray to reduce the adhesive force, and then isolate.

A plurality of semiconductor chips CP affixed on the thermosetting film 7 can be obtained through the steps 1A to 5A.

Next, it is preferable to divide|segment the thermosetting film 7 by which the some semiconductor chip CP is affixed into the same shape as the semiconductor chip CP, and to obtain the semiconductor chip CP with the thermosetting film 7. As a division|segmentation method of the thermosetting film 7, methods, such as laser dicing by a laser beam, expand, and melting, are applicable, for example.

In FIG. 9, the semiconductor chip CP with the thermosetting film 7 divided|segmented into the same shape as the semiconductor chip CP is shown.

The semiconductor chip CP with the thermosetting film 7 is further, if necessary, an expand step of widening the distance between the semiconductor chips CP, a rearrangement step of arranging a plurality of semiconductor chips CP with the spaced apart, After the inversion process etc. which reverse the front and back of some semiconductor chip CP are implemented suitably, it affixes (diamond touch) to a board|substrate from the thermosetting film 7 side. Then, a semiconductor chip and a board|substrate can be fixed by thermosetting a thermosetting film.

The manufacturing method of one aspect of this invention may not include process 3A in manufacturing method A. When step 3A is not included, step 4A' may be included in place of step 4A.

Step 4A': A step of separating the pressure-sensitive adhesive layer (X1) from the support by heating the pressure-sensitive adhesive sheet above the expansion start temperature (t)

When using a double-sided adhesive sheet as an adhesive sheet of one aspect of this invention, the manufacturing method of the semiconductor device of a 1st aspect may be a manufacturing method (hereinafter also referred to as "manufacturing method B") including the following steps 1B to 4B. .

Process 1B: The process of affixing a processing object to the adhesive layer (X1) which the adhesive sheet has, and affixing a support body to the adhesive layer (X2) which the said adhesive sheet has

Step 2B: A step of performing one or more treatments selected from grinding treatment and shredding treatment on the object to be processed

Step 3B: Step of affixing a thermosetting film having thermosetting properties on the surface of the object to be processed on the opposite side to the pressure-sensitive adhesive layer (X1)

Step 4B: A step of separating the pressure-sensitive adhesive layer (X1) and the object to be processed by heating the pressure-sensitive adhesive sheet to a temperature above the expansion start temperature (t) and below 120°C

Steps 1B to 3B are explained by changing the pressure-sensitive adhesive layer (X1) in the description of the steps 1A to 3A to the pressure-sensitive adhesive layer (X2), and the pressure-sensitive adhesive layer (X2) to the pressure-sensitive adhesive layer (X1).

Step 4B is a step of separating the pressure-sensitive adhesive layer (X1) from the object to be processed by heating the pressure-sensitive adhesive sheet to the expansion start temperature (t) or higher and to 120°C or lower.

Heating conditions, such as heating temperature of the adhesive sheet in process 4B, are the same as description in process 4A.

A plurality of semiconductor chips affixed on the thermosetting film can be obtained by step 4B. Then, similarly to the case of manufacturing method A mentioned above, a thermosetting film can be divided|segmented and the semiconductor chip with a thermosetting film can be obtained.

The manufacturing method B may have the process 5B of isolate|separating the adhesive layer (X2) and the said support body after process 4B.

What is necessary is just to select the method of isolate|separating an adhesive layer (X2) and a support body suitably according to the kind of adhesive layer (X2). For example, in the case where the pressure-sensitive adhesive layer (X2) is a pressure-sensitive adhesive layer in which the adhesive force is lowered by irradiation with an energy ray, the pressure-sensitive adhesive layer (X2) may be irradiated with an energy ray to reduce the adhesive force, and then isolate.

In the manufacturing method B of the manufacturing method of one aspect of this invention, the thing which does not include the process 3B may be sufficient. When step 3B is not included, step 4B' may be included in place of step 4B.

Step 4B': A step of separating the pressure-sensitive adhesive layer (X1) from the object to be processed by heating the pressure-sensitive adhesive sheet to the expansion start temperature (t) or higher

<The manufacturing method of the semiconductor device of another aspect>

The manufacturing method of the semiconductor device of this invention is not limited to the manufacturing method of the semiconductor device of the above-mentioned 1st aspect, The manufacturing method of the semiconductor device of an aspect different from the 1st aspect may be sufficient.

As an example of the manufacturing method of the semiconductor device of another aspect, the method of using the adhesive sheet of one aspect of this invention as a sheet|seat for temporarily fixing for test|inspecting an inspection object as a part of a manufacturing process is mentioned. Examples of the inspection performed on the object to be inspected include a defect inspection using an optical microscope and a laser (eg, a dust inspection, a surface flaw inspection, a wiring pattern inspection, etc.), and a surface inspection by the naked eye.

Examples of the object to be inspected include semiconductor chips, semiconductor wafers, compound semiconductors, semiconductor packages, electronic components, LED elements, sapphire substrates, displays, and panel substrates.

When the adhesive sheet of one aspect of the present invention is used as a sheet for temporarily fixing for inspecting an inspection object, it can be inspected in a state in which a plurality of inspection objects are affixed to the pressure-sensitive adhesive layer (X1) of the adhesive sheet. After the inspection, for example, a part of the pressure-sensitive adhesive layer (X1) to which the plurality of inspection objects are affixed is locally heated, and the specific inspection object affixed to the part may be selectively heated and peeled. . At this time, since the pressure-sensitive adhesive sheet of one aspect of the present invention can be peeled by heating at a low temperature, it is excellent in workability and energy saving of the heating peeling operation, and even if the object to be inspected is easily changed by heat, when peeled by heating It is possible to suppress the thermal change of the inspection object due to the heating of the

As another example of the manufacturing method of the semiconductor device of another aspect, the method of separating the object to be processed affixed to another sheet|seat from the said other sheet|seat using the adhesive sheet of one aspect of this invention is mentioned.

For example, a plurality of semiconductor chips with an increased interval on the expand tape are affixed to the adhesive surface of the expand tape, but the operation of picking up these chips one by one is complicated. According to the method for manufacturing a semiconductor device of one aspect of the present invention, the pressure-sensitive adhesive layer (X1) of the pressure-sensitive adhesive sheet of one aspect of the present invention is adhered to the surface of the plurality of semiconductor chips affixed on the expand tape, and then Thus, by peeling the expanded tape from the plurality of semiconductor chips, it is possible to collectively separate the plurality of semiconductor chips from the expanded tape.

A plurality of semiconductor chips affixed on the pressure-sensitive adhesive sheet of one embodiment of the present invention can be obtained through the above-described process. After that, the plurality of semiconductor chips can be easily separated by heating the pressure-sensitive adhesive layer (X1) to the expansion start temperature (t) or higher of the thermally expansible particles. At this time, since the pressure-sensitive adhesive sheet of one aspect of the present invention can be peeled by heating at a low temperature, it is excellent in workability and energy saving of the heating peeling operation, and even if the adherend is easily changed by heat, it can be peeled by heating. The thermal change of the adherend due to heating can be suppressed.

The separated plurality of semiconductor chips may be transferred to another adhesive sheet, or once separated, may be subjected to a rearrangement step of aligning the plurality of semiconductor chips.

(Example)

The present invention will be specifically described with reference to the following examples, but the present invention is not limited to the following examples.

On the other hand, in the following description, "non-expandable pressure-sensitive adhesive layer (X1')" means a pressure-sensitive adhesive layer that does not contain thermally expansible particles, and the pressure-sensitive adhesive layer and shear storage modulus G of the pressure-sensitive adhesive sheet produced in Comparative Examples to be described later. The adhesive layer which does not contain the thermally expansible particle produced for the measurement of ' corresponds to a non-expandable adhesive layer (X1').

The physical property values in the following synthesis examples and Examples are values measured according to the following method.

[Mass Average Molecular Weight (Mw)]

It measured under the following conditions using the gel permeation chromatography apparatus (The Tosoh Corporation make, product name "HLC-8020"), and the value measured by standard polystyrene conversion was used.

(Measuring conditions)

・Column: "TSK　guard　column　HXL-L", "TSK　gel　G2500HXL", "TSK　gel　G2000HXL" and "TSK　gel　G1000HXL" (all manufactured by Tosoh Corporation) in sequence

·Column temperature: 40℃

·Developing solvent: tetrahydrofuran

・Flow rate: 1.0 mL/min

[Thickness of each layer]

It measured using the static pressure thickness measuring machine (Model number: "PG-02J", standard specification: based on JIS K6783, Z1702, Z1709) manufactured by Techlock Corporation.

[Average particle diameter (D ₅₀ ), 90% particle diameter (D ₉₀ ) of thermally expandable particles]

The particle distribution of the thermally expansible particle|grains before expansion at 23 degreeC was measured using the laser diffraction type particle size distribution analyzer (For example, the Malvern company make, product name "Master Cider 3000").

Then, the particle size of the cumulative volume frequency calculated from the side smaller in particle size distribution the particle diameter corresponding to 50% and 90%, respectively, "average particle diameter of the heat-expandable particles (D _50)" or the 90% particle diameter of the "heat-expandable particles ( D ₉₀ )”.

[Storage modulus E' of base material (Y)]

Using a dynamic viscoelasticity measuring apparatus (manufactured by TA Instruments, product name "DMAQ800") using the substrate Y cut to 5 mm in length x 30 mm in width as a test sample, a test start temperature of 0 ° C., a test end temperature of 200 ° C., The storage modulus E' at a predetermined temperature was measured under the conditions of a temperature increase rate of 3°C/min, a frequency of 1 Hz, and an amplitude of 20 µm.

[Shear storage modulus G' (23) at 23° C. of the pressure-sensitive adhesive layer (X1)]

The pressure-sensitive adhesive layer (X1) having a diameter of 8 mm x thickness of 3 mm was used as a test sample, and using a viscoelasticity measuring device (manufactured by Anton Paar, device name “MCR300”), a test start temperature of 0° C. and a test end temperature of 300° C. , the shear storage modulus G'(23) at 23°C was measured by the torsional shear method under conditions of a temperature increase rate of 3°C/min and a frequency of 1 Hz.

[Shear storage modulus G' of the non-expandable pressure-sensitive adhesive layer (X1')]

In order to measure the shear storage modulus G' excluding the influence of thermally expansible particles, in each Example, a non-expandable pressure-sensitive adhesive layer (X1) having the same configuration as the pressure-sensitive adhesive layer (X1) except that it does not contain thermally expandable particles. ') was prepared as a sample for measuring the shear storage modulus corresponding to the pressure-sensitive adhesive layer (X1) of each Example, and the shear storage modulus G' was measured.

In addition, the shear storage modulus G' of the non-expandable adhesive layer (X1') produced by the comparative example was also measured according to this evaluation method.

A non-expandable pressure-sensitive adhesive layer (X1') having a diameter of 8 mm x a thickness of 3 mm was used as a test sample, and using a viscoelasticity measuring device (manufactured by Anton Paar, device name “MCR300”), the test start temperature was 0° C. and the test was completed. Under the conditions of a temperature of 300 ° C., a temperature increase rate of 3 ° C./min., and a frequency of 1 Hz, the shear storage modulus G' (23) at 23 ° C. and the expansion start temperature (t) of the thermally expandable particles by the torsional shear method The shear storage modulus G'(t) of was measured.

On the other hand, the expansion start temperature (t) of the thermally expansible particles of the non-expandable pressure-sensitive adhesive layer (X1'), which is a sample for measuring shear storage modulus, is the thermal expansion contained in the adhesive layer (X1) of the embodiment corresponding to the sample for shear storage modulus measurement. It means the expansion initiation temperature (t) of the stellar particles, and in this Example, it means 88°C as will be described later.

In addition, since the adhesive sheet produced by the comparative example does not have an expansion initiation temperature (t), the shear storage modulus G' in 88 degreeC similar to an Example was measured.

Synthesis Example 1

(Synthesis of urethane acrylate-based prepolymer)

100 parts by mass of polypropylene glycol having a mass average molecular weight (Mw) of 3,000 (solid content conversion; the same hereinafter), 4 parts by mass of hexamethylene diisocyanate, and 0.02 parts by mass of dioctyltin dilaurate are mixed, and the mixture is heated at 80° C. for 6 hours. A reaction was obtained by stirring. About the obtained reaction material, when the IR spectrum was measured by infrared spectroscopy, it was confirmed that the isocyanate group has substantially lose|disappeared.

Then, 1 mass part of 2-isocyanate ethyl acrylate was mixed with respect to the whole quantity of the obtained reaction material, and the urethane acrylate type prepolymer was obtained by stirring at 80 degreeC for 3 hours. About the obtained urethane acrylate type prepolymer, when the IR spectrum was measured by infrared spectroscopy, it was confirmed that the isocyanate group has substantially lose|disappeared. The mass average molecular weight (Mw) of the obtained urethane acrylate type prepolymer was 25,000.

Examples 1-22

(Preparation of polymerizable composition)

Each component shown in Table 1 was mixed by the compounding composition shown in Table 1, and the solvent-free type|mold polymerizable composition was obtained.

In addition, the detail of each component described in Table 1 is as follows.

[Polymerizable Vinyl Monomer]

2EHA: 2-ethylhexyl acrylate (component (a1-1))

IBXA: isobornyl acrylate (component (a1-2))

HEA: 2-hydroxyethyl acrylate (component (a1-3))

4HBA: 4-hydroxybutyl acrylate (component (a1-3))

[Polyfunctional (meth)acrylate monomer]

Trifunctional monomer: isocyanuric acid ethylene oxide modified triacrylate (component (a1-4))

[Polyfunctional (meth)acrylate prepolymer]

Urethane acrylate-based prepolymer: prepared in Synthesis Example 1 (component (a2))

Polyacrylate-based prepolymer: “KANEKA XMAP (registered trademark) RC100C” (manufactured by Kaneka, Ltd., polyacrylic prepolymer having acryloyl groups at both ends, mass average molecular weight (Mw): 21,500) (component (a2))

[Photoinitiator]

1-Hydroxycyclohexylphenylketone

[Thermal Expansive Particles]

AkzoNobel Co., Ltd. product name "ExPancel (registered trademark) 031-40" (DU type), expansion start temperature (t) = 88 ° C, average particle diameter (D ₅₀ ) = 12.6 µm, 90% particle diameter (D ₉₀ ) = 26.2 μm

In addition, "-" in "composition of an adhesive layer (X1) or a non-expandable adhesive layer (X1')" of Table 1 means that the said component was not mix|blended.

(Production of adhesive sheet)

Using the solvent-free polymerizable composition prepared above, an adhesive sheet was prepared in the following procedure.

A solvent-free polymerizable composition was applied onto the release-treated surface of a polyethylene terephthalate (PET) release film (manufactured by Lintec Corporation, product name "SP-PET381031", thickness: 38 µm) to form a polymerizable composition layer. . The polymerizable composition layer was subjected to preliminary polymerization by irradiating ultraviolet rays under the conditions of an illuminance of 150 mW/cm 2 and a light amount of 100 mJ/cm 2 . In addition, the thickness of the polymeric composition layer was adjusted so that the thickness of the adhesive layer (X1) obtained might become the thickness of Table 1.

Next, on the exposed surface of the polymerizable composition layer, a polyethylene terephthalate film (manufactured by Toyobo Corporation, Cosmoshine (registered trademark), part number "A4300", thickness: 50 µm) as a substrate (Y) was affixed to obtain a laminate in which a release film, a polymerizable composition layer, and a substrate (Y) were laminated in this order. On the other hand, the storage elastic modulus E' (23) at 23° C. of the substrate (Y) is 3.0 × 10 ⁹ Pa, and the storage elastic modulus E′ (t) at the expansion start temperature (t) of the thermally expandable particles of the substrate (Y) is 2.4×10 ⁹ Pa.

The laminate obtained above is irradiated with ultraviolet rays from the release film side under the conditions of an illuminance of 200 mW/cm 2 and a light amount of 2,000 mJ/cm 2 (500 mJ/cm 2 is irradiated 4 times) to form a pressure-sensitive adhesive layer (X1), and a release film , an adhesive layer (X1) and a base material (Y) were laminated in this order to obtain an adhesive sheet.

In addition, said illuminance and light quantity at the time of ultraviolet irradiation are the values measured using the illuminance and light quantity meter (The product made by EIT, product name "UV power Puck II").

Comparative Examples 1 to 5

Except having changed the composition of the adhesive layer (X1) in Example 1 to the composition shown in Table 1, it carried out similarly to Example 1, and a peeling film, a non-expandable adhesive layer (X1') and a base material (Y) An adhesive sheet laminated in this order was obtained.

Next, the following evaluation was performed about the adhesive sheet produced in each example. Table 2 shows the evaluation results.

[Measurement of the adhesive force at 23°C before thermal expansion of the pressure-sensitive adhesive layer (X1)]

The release film is removed from the pressure-sensitive adhesive layer (X1) of the pressure-sensitive adhesive sheet cut to 25 mm × 250 mm, and the surface of the exposed pressure-sensitive adhesive layer (X1) is applied to the mirror surface of the silicon mirror wafer 2 according to JIS Z0237:2000 It bonded together with a kg rubber roller, and was left still for 20 minutes in the environment of 23 degreeC and 50 %RH (relative humidity) immediately after that.

After standing under the above conditions, under an environment of 23° C. and 50% RH (relative humidity), using a tensile tester (A&DJ, product name “Tensiron (registered trademark)”), JIS Z0237: Based on 2000, the adhesive force was measured by the 180 degreeC peeling method at the tensile rate of 300 mm/min.

[Measurement of the adhesive force at 23°C after thermal expansion of the pressure-sensitive adhesive layer (X1)]

Further, the above-described test sample was placed on a hot plate such that the silicon mirror wafer was on the side in contact with the hot plate and the pressure-sensitive adhesive sheet side was on the side not in contact with the hot plate, and 100 or more than the expansion start temperature of the thermally expansible particles. After heating at °C for 1 minute and leaving it to stand for 60 minutes in a standard environment (23 °C, 50%RH (relative humidity)), according to JIS Z0237:2000, by the 180 °C peeling method, at a tensile rate of 300 mm/min. The adhesive force of the adhesive layer (X1) was measured.

On the other hand, when fixing an adhesive sheet for a measurement, adhesive force was too small and it peeled unintentionally, and when the measurement of adhesive force was difficult, the adhesive force was 0 N/25 mm.

[Evaluation of self-peelability]

Remove the peeling film from the pressure-sensitive adhesive layer (X1) of the pressure-sensitive adhesive sheet cut to 50 mm x 50 mm, and set the surface of the exposed pressure-sensitive adhesive layer (X1) to the mirror surface of the silicon mirror wafer, 2 according to JIS Z0237:2000 It bonded with a kg rubber roller, and what was left still for 20 minutes in 23 degreeC and 50 %RH (relative humidity) environment immediately after that was made into the test sample. Next, the test sample is placed on a hot plate such that the silicon mirror wafer is on the side that is in contact with the hot plate and the pressure-sensitive adhesive sheet side is on the side that does not come into contact with the hot plate, and is equal to or higher than the expansion start temperature of the thermally expandable particles. It was heated at 100°C for a maximum of 60 seconds. The ratio (%) of the peeling area of the adhesive sheet at the time of heating for 60 second (the area of peeling area *100/the whole adhesive sheet) was calculated|required, and it evaluated based on the following reference|standard.

A: What the adhesive sheet peeled all over within 60 seconds.

B: What heated for 60 seconds and peeled was 30 % or more and less than 100 %.

C: What was heated for 60 second and the peeled area was less than 30 %.

In addition, about the thing of evaluation "A", the time (second) required until full surface peeling was measured.

[Method for measuring adhesive strength and self-peelability of non-expandable pressure-sensitive adhesive layer (X1') at 23°C]

Regarding the adhesive force and self-peelability at 23°C of the non-expandable pressure-sensitive adhesive layer (X1') prepared in Comparative Examples 1 to 5, in the description of the method for measuring the adhesive strength and self-peelability of the pressure-sensitive adhesive layer (X1) at 23°C It measured according to the method which substituted the adhesive layer (X1) in the non-expandable adhesive layer (X1').

However, "before thermal expansion" and "after thermal expansion" in "Adhesive force at 23 ° C. of the non-expandable adhesive layer (X1') of Table 2" in Comparative Examples 1-5, It shall mean "before heat treatment" and "after heat treatment equivalent to the thermal expansion treatment of the Example", and "the heat treatment equivalent to the thermal expansion treatment of the Example" means [adhesive force at 23 ° C. after the thermal expansion of the pressure-sensitive adhesive layer (X1) Measurement of] shall mean the heat treatment described in

[Table 1]

[Table 2]

Table 2 shows that the adhesive sheets of Examples 1-22 can heat-peel at low temperature (100 degreeC), all having sufficient adhesive force before heat peeling. Moreover, it turns out that these adhesive sheets can adjust adhesive force and self-peelability by adjusting the composition of a polymeric composition, the thickness of adhesive layer (X1), etc. On the other hand, all of the adhesive sheets of Comparative Examples 1-5 were not able to peel by heating.

1a, 1b, 2a, 2b: adhesive sheet
10, 10a, 10b: release material
3: support
4: laser light irradiation device
5: Reform area
6: Grinder
7: thermosetting film
8: support sheet
W: semiconductor wafer
W1: Circuit surface of semiconductor wafer and semiconductor chip
W2: Back side of semiconductor wafer and semiconductor chip
CP: semiconductor chip

Claims (15)

A pressure-sensitive adhesive sheet having a base material (Y), an energy-beam polymerizable component, and a pressure-sensitive adhesive layer (X1) containing thermally expansible particles having an expansion initiation temperature (t) of 50 to 110°C,
The pressure-sensitive adhesive layer (X1) is a layer formed by irradiating an energy ray to a polymerizable composition containing the energy ray polymerizable component and the thermally expansible particles to form a polymer of the energy ray polymerizable component. According to claim 1,
The adhesive sheet whose content of the said thermally expansible particle is 1-30 mass % with respect to the total mass (100 mass %) of the adhesive layer (X1). 3. The method of claim 1 or 2,
The adhesive sheet whose thickness in 23 degreeC of adhesive layer (X1) is 5-150 micrometers. 4. The method according to any one of claims 1 to 3,
The adhesive sheet whose adhesive force in 23 degreeC of an adhesive layer (X1) is 0.1-12.0 N/25 mm. 5. The method according to any one of claims 1 to 4,
The adhesive sheet whose average particle diameter in 23 degreeC of the said thermally expansible particle is 1-30 micrometers. 6. The method according to any one of claims 1 to 5,
The adhesive sheet which has the base material (Y), the adhesive layer (X1) provided in one surface side of the base material (Y), and the adhesive layer (X2) provided in the other surface side of the base material (Y). 7. The method of claim 6,
The adhesive sheet whose adhesive layer (X2) is an adhesive layer in which adhesive force falls by hardening|curing by irradiating an energy ray. A method for producing the pressure-sensitive adhesive sheet according to any one of claims 1 to 7, comprising:
The method of forming the pressure-sensitive adhesive layer (X1) includes a step of irradiating an energy ray to a polymerizable composition containing the energy ray polymerizable component and the thermally expansible particles to form a polymer of the energy ray polymerizable component , a method for manufacturing an adhesive sheet. 9. The method of claim 8,
The method for forming the pressure-sensitive adhesive layer (X1) includes the following steps I and II, the method for producing a pressure-sensitive adhesive sheet.
Step I: Step of forming a polymerizable composition layer comprising the polymerizable composition on one surface side of the base material (Y)
Process II: The process of forming the polymer of the said energy-beam polymeric component by irradiating an energy-beam to the said polymeric composition layer, and forming the adhesive layer (X1) containing the said polymer and the said thermally expansible particle. 10. The method according to claim 8 or 9,
The method for producing a pressure-sensitive adhesive sheet, wherein the polymerizable composition does not contain a solvent. 11. The method according to any one of claims 8 to 10,
The manufacturing method of the adhesive sheet which does not include the process of heating the said polymerizable composition. The object to be processed is affixed to the pressure-sensitive adhesive sheet according to any one of claims 1 to 7,
One or more treatments selected from grinding treatment and slicing treatment are performed on the object to be processed;
After performing the said process, the manufacturing method of a semiconductor device including the process of heating the said adhesive sheet to the said expansion start temperature (t) or more and 120 degrees C or less to expand the adhesive layer (X1). A method for manufacturing a semiconductor device comprising the following steps 1A to 5A.
Process 1A: The process of affixing a processing object to the adhesive layer (X2) which the adhesive sheet has as described in Claim 6, and affixing a support body to the adhesive layer (X1) which the said adhesive sheet has
Step 2A: A step of performing one or more treatments selected from grinding treatment and shredding treatment on the object to be processed
Step 3A: Step of affixing a thermosetting film having thermosetting properties on the surface of the object to be processed on the opposite side to the pressure-sensitive adhesive layer (X2)
Step 4A: A step of separating the pressure-sensitive adhesive layer (X1) from the support by heating the pressure-sensitive adhesive sheet to the expansion initiation temperature (t) or higher and to 120°C or lower
Step 5A: Step of separating the pressure-sensitive adhesive layer (X2) and the object to be processed 14. The method of claim 13,
The pressure-sensitive adhesive layer (X2) is a pressure-sensitive adhesive layer that is cured by irradiating an energy ray to decrease the adhesive strength,
The process 5A is a process of isolating the pressure-sensitive adhesive layer (X2) from the object to be processed by curing the pressure-sensitive adhesive layer (X2) by irradiating the pressure-sensitive adhesive layer (X2) with an energy ray. A method for manufacturing a semiconductor device comprising the following steps 1B to 4B.
Process 1B: The process of affixing an object to be processed to the adhesive layer (X1) which the adhesive sheet has as described in Claim 6, and affixing a support body to the adhesive layer (X2) which the said adhesive sheet has
Step 2B: A step of performing one or more treatments selected from grinding treatment and shredding treatment on the object to be processed
Step 3B: Step of affixing a thermosetting film having thermosetting properties on the surface of the object to be processed on the opposite side to the pressure-sensitive adhesive layer (X1)
Step 4B: A step of separating the pressure-sensitive adhesive layer (X1) from the object to be processed by heating the pressure-sensitive adhesive sheet to a temperature above the expansion start temperature (t) and below 120°C

Images